Changes in Bi-ventricular Function After Hematopoietic Stem Cell Transplant as Assessed by Speckle Tracking Echocardiography

Abstract

Hematopoietic stem cell transplant (HSCT) is a therapeutic option for patients with sickle cell disease (SCD) and severe acquired aplastic anemia (SAA). HSCT may have beneficial effects on ventricular function in damaged myocardium. We hypothesized improvement in ventricular performance and pulmonary hypertension following HSCT with strain echocardiography in SCD and SAA. Echocardiographic strain and other standard functional data were obtained via retrospective cohort analysis of patients (n = 23) with SCD and SAA who underwent HSCT and were followed at a single center between 2000 and 2014. Left ventricular global longitudinal strain was below normal at baseline, and decreased significantly (from − 16.6 to − 11.1, P = 0.05) from pre-HSCT to the initial post-HSCT echocardiogram at 109 (SD ± 83) days. At 351 (SD ± 115) days, longitudinal strain improved significantly from initial decline (from − 11.1 to − 17.5, P = 0.009) but was comparable to baseline (P = 0.43). Other measurements of bi-ventricular function did not change significantly. Tricuspid regurgitation velocities as surrogates for pulmonary hypertension improved in the subset of patients with baseline elevated values although data points were limited. Abnormal myocardial systolic function was detected at baseline with strain imaging. HSCT was associated with initial worsening longitudinal strain values, followed by improvement to baseline levels by 1 year. Insufficient data exist on whether pulmonary hypertension improves after HSCT.

http://ift.tt/2gSASu8

Electronic tunneling through a fullerene-like molecular bridge

Abstract

This study was conducted to consider the electronic transport properties of the \(N_{36} B_{36}\) molecule, using the Green's function method based on the GW model. The number, width, height and position of density of state peaks are dramatically dependent on the correlation effect, the contact type and symmetric properties of the molecule. Also, negative differential resistance behavior was observed for all modes in voltages 4.4 V (− 4.5 V) to 4.7 V (− 4.7 V). The \(N_{36} B_{36}\) molecule behaves as an insulator where the total current becomes zero for the same values of the gate voltages but acts as a metal at other values. Therefore, the physical picture of electron conduction may change in \(N_{36} B_{36}\) —based molecular devices and it could behave as a semiconductor.

http://ift.tt/2z7FruM

Influence of substitution of various functional groups on inhibition efficiency of TEMPO analogues on styrene polymerization

Abstract

Vinyl monomers such as styrene may undergo undesired polymerization reactions during the industrial processes in which they are synthesized and purified. To avoid this undesired phenomenon, polymerization inhibitors such as (2,2,6,6-tetramethylpiperidin-1-yl)oxidanyl (TEMPO) and its analogues can be used. An inhibitor and stability screening setup built in-house was used to compare the effectiveness of thirteen TEMPO analogues in inhibiting the polymerization of styrene in toluene at 130 °C. The data show that the substituent in the 4′-position in the cyclic structure of the TEMPO molecules strongly influenced their effectiveness in inhibiting polymerization. Computational methods based on the density functional theory (DFT) approach have been utilized to understand the reactivity of the TEMPO analogues. The global reactivity descriptors derived from the DFT calculations indicate that the TEMPO analogues with high global electrophilicity are more effective than those with low global electrophilicity in inhibiting the polymerization. The data suggest that the solubility of the TEMPO analogues in toluene and the keto–enol tautomerism of certain molecules may also affect their ability to inhibit styrene polymerization.

http://ift.tt/2z4bGsS

Asian patients with Hinchey Ia acute diverticulitis: a condition for the ambulatory setting?

Abstract

Background

Diverticulitis in Asians is a different disease entity from Western counterparts. Few Asian studies have evaluated the management of acute Hinchey Ia diverticulitis with consideration for outpatient management. The purpose of this study was to evaluate the outcomes of Asian patients with Hinchey Ia acute diverticulitis.

Methods

A retrospective review of all patients who were treated for Hinchey Ia acute colonic diverticulitis between 2012 and 2014 was performed. All patients were diagnosed on computed tomography (CT).

Results

There were 129 patients with Hinchey Ia acute diverticulitis. Fifty-five (42.6%) patients were male, and the median age was 54 years (range, 30–86). Eighty-seven (67.4%) patients had right-sided diverticulitis.

Most patients were treated empirically with intravenous ceftriaxone and metronidazole (89.1%). They were then discharged with oral antibiotics. Only 6.1% of patients had a positive blood culture. The median length of stay in the hospital was 4 (range, 3–4) days.

Only three (2.3%) patients were readmitted for acute diverticulitis within 30 days. They were managed with antibiotics and discharged well. The repeated CT scans reconfirmed Hinchey Ia diverticulitis. No patients required emergency surgery, and there were no 30-day mortalities.

Conclusion

Asian patients with Hinchey Ia diverticulitis recovered well with conservative management and could be amenable to outpatient therapy. Future prospective studies should be performed amongst Asians to evaluate managing this condition in an ambulatory setting.

http://ift.tt/2gQuraA

Post-Stroke Cognitive Impairments and the Potential for Treatment with Cellex

Objective. To assess the neuropsychological characteristics of post-stroke cognitive impairments (PSCI) in the acute period of ischemic stroke (IS) and to evaluate the efficacy of Cellex. Materials and methods. Complex neuropsychological testing was performed in 288 patients in the acute period of IS. Cellex was used in addition to basal treatment in 30 patients at a dose of 0.1 mg (1 ml) s.c. for 10 days, with treatment being initiated in the hyperacute period. Results and discussion. Multifunctional PSCI was detected in 87% of the patients in the acute period of IS. Most patients showed impairments to attention, regulatory functions, speech, and memory. More than a third of patients showed multifunctional non-amnestic cognitive impairments. Monofunctional nonamnestic PSCI was encountered in 5.5% of cases. Isolated memory deficit was found in 2% of patients. Most elderly patients displayed PSCI, mostly the mixed variant. Isolated decreases in the rate or regulation of cognitive activity dominated among young and middle-aged patients, with one in four patients showing mixed cognitive impairments. A tendency to greater age was seen in patients with mixed-type PSCI. Analysis of the efficacy of Cellex in the acute period of IS showed that use was linked with improvements in cognitive status and the state of neurodynamic, regulatory, and visuospatial functions. The neurotrophic agent Cellex was effective in correcting PSCI in the acute period of IS.

http://ift.tt/2gX0hWW

Manganese (II) Removal from Aqueous Solutions by Bacillus cereus : an Optimization Study Using Experimental Design and Response Surface Methodology

Abstract

The present study was carried out in order to investigate the removal of soluble Mn²⁺ from an aqueous solution using Bacillus cereus. A manganese aqueous solution at 50 mg L⁻¹ was treated, and the product was less than 1 mg L⁻¹ of residual concentration, which complied with environmental regulations. Before the optimization, B. cereus was able to remove Mn²⁺ ions from an aqueous solution; however, the residual content was around 2.5 mg L⁻¹. Screening experiments aiming at defining the effects of the growth medium composition indicated that both casamino acid-peptone and yeast extract contributed to manganese removal. These experiments also showed the interaction between these two components of the culture media, nevertheless the use of glucose did not prove significant. Considering these observations, the Doehlert design was used to generate a response surface. The model was significant with the p value lower than 0.05 and the lack-of-fit not significant (p > 0.05). The optimized composition of the growth medium was defined as 0.5 g L⁻¹ of casamino acid-peptone and 0.25 g L⁻¹ of yeast extract, whereas glucose could be removed from the original growth medium. When the optimized condition of the growth medium was used, the time required for manganese removal was reduced from 21 to 8 days. After optimization, B. cereus was capable of producing high manganese removal, reducing the residual concentration to levels below 1.0 mg L⁻¹.

http://ift.tt/2gRW3wo

Review of Mechanical Testing and Modelling of Thrombus Material for Vascular Implant and Device Design

Abstract

A thrombus or blood clot is a solid mass, made up of a network of fibrin, platelets and other blood components. Blood clots can form through various pathways, for example as a result of exposed tissue factor from vascular injury, as a result of low flow/stasis, or in very high shear flow conditions. Embolization of cardiac or vascular originating blood clots, causing an occlusion of the neurovasculature, is the major cause of stroke and accounts for 85% of all stroke. With mechanical thrombectomy emerging as the new standard of care in the treatment of acute ischemic stroke (AIS), the need to generate a better understanding of the biomechanical properties and material behaviour of thrombus material has never been greater, as it could have many potential benefits for the analysis and performance of these treatment devices. Defining the material properties of a thrombus has obvious implications for the development of these treatment devices. However, to-date this definition has not been adequately established. While some experimentation has been performed, model development has been extremely limited. This paper reviews the previous literature on mechanical testing of thrombus material. It also explores the use of various constitutive and computational models to model thrombus formation and material behaviour.

http://ift.tt/2h0hgrD

Multifunctional Beta Ti Alloy with Improved Specific Strength

Abstract

Gum metals feature properties such as ultrahigh strength, ultralow elastic modulus, superelasticity, and superplasticity. They are composed of elements from Groups 4 and 5 of the periodic table and exist when the valance electron concentration ( \(\overline{e/a}\) ) is 4.24; the bond order ( \(\overline{\text{Bo}}\) ) is 2.87; and the "d" electron-orbital energy level ( \(\overline{\text{Md}}\) ) is 2.45 eV. Typical compositions include Ti–23Nb–2Zr–0.7Ta–O and Ti–12Ta–9Nb–6Zr–3 V–O, which contain large amounts of heavy Group-5 elements such as Nb and Ta. In the present study, to improve the specific strength of a multifunctional beta Ti alloy, three alloys (Ti–20Nb–5Zr–1Fe–O, Ti–12Zr–10Mo–4Nb–O, and Ti–24Zr–9Cr–3Mo–O) were designed by satisfying the above three requirements while adding Fe, Mo, and Cr, which are not only lightweight but also have strong hardening effects. Microstructural and mechanical property analyses revealed that Ti–20Nb–5Zr–1Fe–O has a 25% higher specific strength than gum metal while maintaining an ultralow elastic modulus.

http://ift.tt/2gQEP2b

Differentiation of grade II/III and grade IV glioma by combining “T1 contrast-enhanced brain perfusion imaging” and susceptibility-weighted quantitative imaging

Abstract

Purpose

MRI is a useful method for discriminating low- and high-grade glioma using perfusion MRI and susceptibility-weighted imaging (SWI). The purpose of this study is to evaluate the usefulness of T1-perfusion MRI and SWI in discriminating among grade II, III, and IV gliomas.

Methods

T1-perfusion MRI was used to measure relative cerebral blood volume (rCBV) in 129 patients with glioma (70 grade IV, 33 grade III, and 26 grade II tumors). SWI was also used to measure the intratumoral susceptibility signal intensity (ITSS) scores for each tumor in these patients. rCBV and ITSS values were compared to seek differences between grade II vs. grade III, grade III vs. grade IV, and grade III+II vs. grade IV tumors.

Results

Significant differences in rCBV values of the three grades of the tumors were noted and pairwise comparisons showed significantly higher rCBV values in grade IV tumors as compared to grade III tumors, and similarly increased rCBV was seen in the grade III tumors as compared to grade II tumors (p < 0.001). Grade IV gliomas showed significantly higher ITSS scores on SWI as compared to grade III tumors (p < 0.001) whereas insignificant difference was seen on comparing ITSS scores of grade III with grade II tumors. Combining the rCBV and ITSS resulted in significant improvement in the discrimination of grade III from grade IV tumors.

Conclusion

The combination of rCBV values derived from T1-perfusion MRI and SWI derived ITSS scores improves the diagnostic accuracy for discrimination of grade III from grade IV gliomas.

http://ift.tt/2xHDwJZ

Epigenetic control of epilepsy target genes contributes to a cellular memory of epileptogenesis in cultured rat hippocampal neurons

Abstract

Hypersynchronous neuronal excitation manifests clinically as seizure (ictogenesis), and may recur spontaneously and repetitively after a variable latency period (epileptogenesis). Despite tremendous research efforts to describe molecular pathways and signatures of epileptogenesis, molecular pathomechanisms leading to chronic epilepsy remain to be clarified. We hypothesized that epigenetic modifications may form the basis for a cellular memory of epileptogenesis, and used a primary neuronal cell culture model of the rat hippocampus to study the translation of massive neuronal excitation into persisting changes of epigenetic signatures and pro-epileptogenic target gene expression. Increased spontaneous activation of cultured neurons was detected 3 and 7 days after stimulation with 10 μM glutamate when compared to sham-treated time-matched controls using calcium-imaging in vitro. Chromatin-immunoprecipitation experiments revealed short-term (3 h, 7 h, and 24 h) and long-term (3 d and 2 weeks) changes in histone modifications, which were directly linked to decreased expression of two selected epilepsy target genes, e.g. excitatory glutamate receptor genes Gria2 and Grin2a. Increased promoter methylation observed 4 weeks after glutamate stimulation at respective genes suggested long-term repression of Gria2 and Grin2a genes. Inhibition of glutamatergic activation or blocking the propagation of action potentials in cultured neurons rescued altered gene expression and regulatory epigenetic modifications. Our data support the concept of a cellular memory of epileptogenesis and persisting epigenetic modifications of epilepsy target genes, which are able to turn normal into pro-epileptic neurons and circuits.

http://ift.tt/2gSdxZu

Effective induction therapy for anti-SRP associated myositis in childhood: A small case series and review of the literature

Abstract

Background

Anti-Signal Recognition Particle associated myopathy is a clinically and histopathologically distinct subgroup of Juvenile Idiopathic Inflammatory Myositis, which is under-recognised in children and fails to respond to conventional first line therapies. We present three cases where remission was successfully induced using combination therapy with intensive rehabilitation.

Case presentations

Three new patients are reported. All 3 cases presented with profound, rapid-onset, proximal myopathy and markedly raised CK, but no rash. Histology revealed a destructive myopathy characterized by scattered atrophic and necrotic fibres with little or no inflammatory infiltrate. All 3 patients responded to induction with cyclophosphamide, IVIG and rituximab, in conjunction with intensive physiotherapy and methotrexate as the maintenance agent. Our patients regained near-normal strength (MMT > 70/80), in contrast with the current literature where >50% of cases reported severe residual weakness.

A literature search on paediatric anti-SRP myositis was performed to June 2016; PubMed was screened using a combination of the following terms: signal recognition particle, autoantibodies, antibodies, myositis, muscular diseases, skeletal muscle, childhood, paediatric, juvenile. Articles in a foreign language were excluded. Nine case studies were found.

Conclusion

This paper supports the hypothesis that anti-SRP myositis is distinct from other JIIM. It is an important differential to JDM and should be considered where there is severe weakness without rash or if highly elevated muscle enzymes (CK > 10,000 U/l) are found. Early identification is essential to initiate aggressive medical and physical therapy. Greater international collaboration and long-term follow-up data is needed to establish the most effective treatment strategy for this rare group of patients.

http://ift.tt/2z97c6f

Enhanced transdermal delivery with less irritation by magainin pore-forming peptide with a N-lauroylsarcosine and sorbitan monolaurate mixture

Abstract

Transdermal drug delivery is advantageous over other conventional drug administration routes. However, it can be inefficient because of the natural barrier of the stratum corneum which is the uppermost layer of the skin. A previous study verified that the treatment of magainin pore-forming peptide with N-lauroylsarcosine (NLS) on human skin can increase skin permeability by 47-fold. However, NLS is well known as a potential skin irritant. The irritation potential of NLS is known to decrease when mixed with sorbitan monolaurate (S20). Encouraged by these results, we combined S20 with magainin-NLS to enhance transdermal drug transport with less skin irritation. In this study, nine groups with magainin and NLS:S20 mixtures at different concentrations and weight fractions were screened to maximize their synergistic effect. To quantify the efficacy to toxicity ratio of each formulation, we defined the ratio as the "enhancement ratio/irritation potential (ER/IP)." The ER was observed by Franz cell diffusion of the target drug fluorescein, and the IP was measured by the cytotoxicity of the NIH/3T3 mouse fibroblast cell line. As a result, the magainin with the NLS:S20 mixture increased the permeability of porcine skin as well as decreased the toxicity. Among the various combinations, a formulation of 2% (w/v) NLS:S20 with a weight fraction of 0.6:0.4 had the largest ER/IP. ATR-FTIR spectroscopy of the formulations and skin was done to analyze the interactions in the formulations themselves and between the formulations and the skin. Both the intercellular lipidic route and transcellular route through the stratum corneum protein were involved in the delivery of fluorescein. This study turned pore-forming peptides into an efficient and safe penetration enhancer by combining them with other chemical penetration enhancers. Moreover, this discovery could be a possible method for enabling the transdermal delivery of macromolecules.

http://ift.tt/2lAo7t6

Oblique retroperitoneal approach for lumbar interbody fusion from L1 to S1 in adult spinal deformity

Abstract

In recent years, with advancements in surgical techniques and instrumentation, the lateral lumbar interbody fusion is being used increasingly as an alternative procedure to anterior approach. In this study, we illustrated a oblique retroperitoneal approach for lumbar interbody fusion with one incision site and tilting of the operation table in adult spinal deformity and evaluate the radiographical findings and clinical outcomes of patients treated using this technique. This study included 32 patients scheduled to undergo anterior and posterior long-level fusions for lumbar degenerative kyphosis or degenerative lumbar scoliosis. Data collected included blood loss, operative time, incision size, and perioperative complications. Pre- and postoperative radiographic parameters and clinical outcome measures were assessed. Mean follow-up time was 26.1 months. The mean blood losses were 107.4 and 102.4 ml, and the mean operative times were 116, 97, and 82 min for the patients within five levels (4 cases), four levels (18 cases), and three levels (10 cases). The mean incision sizes were 14.63, 13.82, and 12.5 cm in the patients with five, four, and three levels. The mean pelvic incidence was 50.3°. The mean preoperative sagittal vertical axis (SVA) was + 13.66 cm, and the last follow-up SVA was + 2.94 cm. The preoperative lumbar lordosis (LL) was 5.79°, and the last follow-up LL was 46.54°. The mean correction angle was 41°. The mean Cobb angle decreased from a preoperative value of 21.55° to 9.6°at the last follow-up. An oblique retroperitoneal approach is very safe, allowing reproducible access from L1 to S1 for lumbar interbody fusion in adult spinal deformity.

http://ift.tt/2z4vxIt

The Risk of Neurodevelopmental Disabilities in Children of Immigrant and Refugee Parents: Current Knowledge and Directions for Future Research

Abstract

This paper systematically reviewed the literature from 2002 to 2016 describing the risks of autism spectrum disorder, intellectual disability and attention deficit hyperactivity disorder in children of immigrant and refugee backgrounds. Compared to children of non-immigrant mothers, 10 studies found increased risk of autism and intellectual disability and four studies found increased risk of autism without identifying concomitant intellectual disability. Very high risks were observed if the mother's country of birth was a developing country or region. One study found higher risk of attention deficit hyperactivity disorder in a sample of children who were refugees. Children of immigrant and refugee backgrounds from developing countries had greater risks of a neurodevelopmental disorder compared to their peers whose mother was locally born.

http://ift.tt/2iQel5g

Interstitial Cystitis: Animal Models

Abstract

In 1990, although the etiology and pathogenesis of the condition then referred to as "interstitial cystitis" (IC) was admitted to be largely or even completely unknown, the widely held implicit working assumptions held that it is a bladder disease. These assumptions implied that if we could discover and correct what was wrong with the bladder itself then we could cure the condition. These assumptions have proved to be largely off base. At that time, the previous suggestions that IC might have a primarily autoimmune or infectious etiology were largely abandoned. The autoimmune hypothesis still remains but has yet to be either been proven nor disproven conclusively.

http://ift.tt/2gQK6qr

Effect of electric field on RbCl quantum pseudodot qubit

Abstract

By employing the variational method of Pekar type, we study the effects of electric field on RbCl quantum pseudodot (QPD) qubits. Our results confirm that (1) the electron oscillates in the RbCl QPD with a certain period; (2) the electron's probability density is a raising function of electric field; (3) the oscillating frequency is an increasing one of the electric field and the two-dimensional electron gas chemical potential. Two ways are found for prolonging the lifetime of the qubit and suppressing the decoherence in the quantum information field.

http://ift.tt/2gRO7Lt

Vibrio hannami sp. nov., Isolated from Seawater

Abstract

A Gram-reaction negative, aerobic, motile, non-pigmented and rod-shaped bacterium, designated as 168GH5-2-16^T, was isolated from seawater Jeju island. Phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that the strain formed a distinct lineage within the genus Vibrio and was most closely related to Vibrio variabilis R-40492^T (96.0%). The DNA G+C content was 49.3 mol%. The major polar lipids were phosphatidylethanolamine (PE) and phosphatidylglycerol (PG). The predominant quinone was ubiquinone-8 (Q-8). The major fatty acids were C_16:0, summed feature 3 (comprising C_16:1ω7c/C_16:1ω6c) and summed feature 8 (C_18:1ω7c/C_18:1ω6c) supported the affiliation of 168GH5-2-16^T to the genus Vibrio. Moreover, the physiological, biochemical, and taxonomic analysis allowed the phenotypic and genotypic differentiation of strain 168GH5-2-16^T from the recognized species of the genus Vibrio. Therefore, strain 168GH5-2-16^T represents a novel species of the genus Vibrio, for which the name Vibrio hannami sp. nov. is proposed, with the type strain 168GH5-2-16^T (=KACC 19277^T = DSM105032^T).

http://ift.tt/2gQPUQY

Synthesis, Antimicrobial and Antioxidant Activity of Pyrazole Based Sulfonamide Derivatives

Abstract

A series of new sulfonamides have been synthesized from Ampyrone with different benzene sulfonyl chlorides to yield the N-1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl) benzenesulfonamides (4a–e). All synthesized compounds were characterized on the basis of FTIR, ¹H NMR, and ¹³C NMR, and also by the aid of mass spectral data. Further, all synthesized compounds have studied for their in vitro antimicrobial activities against selected bacterial as well as fungal strains by the agar well diffusion method. Free radical scavenging activity has been investigated by using DPPH method. Among all the synthesized compounds, 4b, 4d, and 4e exhibited significant antimicrobial and antioxidant activities.

http://ift.tt/2yipiDE

RNA-binding protein HuR enhances mineralocorticoid signaling in renal KC3AC1 cells under hypotonicity

Abstract

Mineralocorticoid receptor (MR) mediates the sodium-retaining action of aldosterone in the distal nephron. Herein, we decipher mechanisms by which hypotonicity increases MR expression in renal principal cells. We identify HuR (human antigen R), an mRNA-stabilizing protein, as an important posttranscriptional regulator of MR expression. Hypotonicity triggers a rapid and reversible nuclear export of HuR in renal KC3AC1 cells, as quantified by high-throughput microscopy. We also identify a key hairpin motif in the 3′-untranslated region of MR transcript, pivotal for the interaction with HuR and its stabilizing function. Next, we show that hypotonicity increases MR recruitment onto Sgk1 promoter, a well-known MR target gene, thereby enhancing aldosterone responsiveness. Our data shed new light on the crucial role of HuR as a stabilizing factor for the MR transcript and provide evidence for a short autoregulatory loop in which expression of a nuclear receptor transcriptionally regulating water and sodium balance is controlled by osmotic tone.

http://ift.tt/2lyjdgj

Experimental design and reporting standards for metabolomics studies of mammalian cell lines

Abstract

Metabolomics is an analytical technique that investigates the small biochemical molecules present within a biological sample isolated from a plant, animal, or cultured cells. It can be an extremely powerful tool in elucidating the specific metabolic changes within a biological system in response to an environmental challenge such as disease, infection, drugs, or toxins. A historically difficult step in the metabolomics pipeline is in data interpretation to a meaningful biological context, for such high-variability biological samples and in untargeted metabolomics studies that are hypothesis-generating by design. One way to achieve stronger biological context of metabolomic data is via the use of cultured cell models, particularly for mammalian biological systems. The benefits of in vitro metabolomics include a much greater control of external variables and no ethical concerns. The current concerns are with inconsistencies in experimental procedures and level of reporting standards between different studies. This review discusses some of these discrepancies between recent studies, such as metabolite extraction and data normalisation. The aim of this review is to highlight the importance of a standardised experimental approach to any cultured cell metabolomics study and suggests an example procedure fully inclusive of information that should be disclosed in regard to the cell type/s used and their culture conditions. Metabolomics of cultured cells has the potential to uncover previously unknown information about cell biology, functions and response mechanisms, and so the accurate biological interpretation of the data produced and its ability to be compared to other studies should be considered vitally important.

http://ift.tt/2yiqNBS

Retinoic acid regulates avian lung branching through a molecular network

Abstract

Retinoic acid (RA) is of major importance during vertebrate embryonic development and its levels need to be strictly regulated otherwise congenital malformations will develop. Through the action of specific nuclear receptors, named RAR/RXR, RA regulates the expression of genes that eventually influence proliferation and tissue patterning. RA has been described as crucial for different stages of mammalian lung morphogenesis, and as part of a complex molecular network that contributes to precise organogenesis; nonetheless, nothing is known about its role in avian lung development. The current report characterizes, for the first time, the expression pattern of RA signaling members (stra6, raldh2, raldh3, cyp26a1, rarα, and rarβ) and potential RA downstream targets (sox2, sox9, meis1, meis2, tgfβ2, and id2) by in situ hybridization. In the attempt of unveiling the role of RA in chick lung branching, in vitro lung explants were performed. Supplementation studies revealed that RA stimulates lung branching in a dose-dependent manner. Moreover, the expression levels of cyp26a1, sox2, sox9, rarβ, meis2, hoxb5, tgfβ2, id2, fgf10, fgfr2, and shh were evaluated after RA treatment to disclose a putative molecular network underlying RA effect. In situ hybridization analysis showed that RA is able to alter cyp26a1, sox9, tgfβ2, and id2 spatial distribution; to increase rarβ, meis2, and hoxb5 expression levels; and has a very modest effect on sox2, fgf10, fgfr2, and shh expression levels. Overall, these findings support a role for RA in the proximal–distal patterning and branching morphogenesis of the avian lung and reveal intricate molecular interactions that ultimately orchestrate branching morphogenesis.

http://ift.tt/2lyZxZI

Epithelial cell senescence: an adaptive response to pre-carcinogenic stresses?

Abstract

Senescence is a cell state occurring in vitro and in vivo after successive replication cycles and/or upon exposition to various stressors. It is characterized by a strong cell cycle arrest associated with several molecular, metabolic and morphologic changes. The accumulation of senescent cells in tissues and organs with time plays a role in organismal aging and in several age-associated disorders and pathologies. Moreover, several therapeutic interventions are able to prematurely induce senescence. It is, therefore, tremendously important to characterize in-depth, the mechanisms by which senescence is induced, as well as the precise properties of senescent cells. For historical reasons, senescence is often studied with fibroblast models. Other cell types, however, much more relevant regarding the structure and function of vital organs and/or regarding pathologies, are regrettably often neglected. In this article, we will clarify what is known on senescence of epithelial cells and highlight what distinguishes it from, and what makes it like, replicative senescence of fibroblasts taken as a standard.

http://ift.tt/2yiqM0M

Distinct functions of Crumbs regulating slit diaphragms and endocytosis in Drosophila nephrocytes

Abstract

Mammalian podocytes, the key determinants of the kidney's filtration barrier, differentiate from columnar epithelial cells and several key determinants of apical–basal polarity in the conventional epithelia have been shown to regulate podocyte morphogenesis and function. However, little is known about the role of Crumbs, a conserved polarity regulator in many epithelia, for slit-diaphragm formation and podocyte function. In this study, we used Drosophila nephrocytes as model system for mammalian podocytes and identified a conserved function of Crumbs proteins for cellular morphogenesis, nephrocyte diaphragm assembly/maintenance, and endocytosis. Nephrocyte-specific knock-down of Crumbs results in disturbed nephrocyte diaphragm assembly/maintenance and decreased endocytosis, which can be rescued by Drosophila Crumbs as well as human Crumbs2 and Crumbs3, which were both expressed in human podocytes. In contrast to the extracellular domain, which facilitates nephrocyte diaphragm assembly/maintenance, the intracellular FERM-interaction motif of Crumbs is essential for regulating endocytosis. Moreover, Moesin, which binds to the FERM-binding domain of Crumbs, is essential for efficient endocytosis. Thus, we describe here a new mechanism of nephrocyte development and function, which is likely to be conserved in mammalian podocytes.

http://ift.tt/2lz2lGo

Mechanisms regulating dendritic arbor patterning

Abstract

The nervous system is populated by diverse types of neurons, each of which has dendritic trees with strikingly different morphologies. These neuron-specific morphologies determine how dendritic trees integrate thousands of synaptic inputs to generate different firing properties. To ensure proper neuronal function and connectivity, it is necessary that dendrite patterns are precisely controlled and coordinated with synaptic activity. Here, we summarize the molecular and cellular mechanisms that regulate the formation of cell type-specific dendrite patterns during development. We focus on different aspects of vertebrate dendrite patterning that are particularly important in determining the neuronal function; such as the shape, branching, orientation and size of the arbors as well as the development of dendritic spine protrusions that receive excitatory inputs and compartmentalize postsynaptic responses. Additionally, we briefly comment on the implications of aberrant dendritic morphology for nervous system disease.

http://ift.tt/2ygGr0l

Endothelial cell apoptosis in angiogenesis and vessel regression

Abstract

Blood vessel regression is an essential process for ensuring blood vessel networks function at optimal efficiency and for matching blood supply to the metabolic needs of tissues as they change over time. Angiogenesis is the major mechanism by which new blood vessels are produced, but the vessel growth associated with angiogenesis must be complemented by remodeling and maturation events including the removal of redundant vessel segments and cells to fashion the newly forming vasculature into an efficient, hierarchical network. This review will summarize recent findings on the role that endothelial cell apoptosis plays in vascular remodeling during angiogenesis and in vessel regression more generally.

http://ift.tt/2lyiFaf

Macrophage migration inhibitory factor (MIF) modulates trophic signaling through interaction with serine protease HTRA1

Abstract

Macrophage migration inhibitory factor (MIF), a small conserved protein, is abundant in the immune- and central nervous system (CNS). MIF has several receptors and binding partners that can modulate its action on a cellular level. It is upregulated in neurodegenerative diseases and cancer although its function is far from clear. Here, we report the finding of a new binding partner to MIF, the serine protease HTRA1. This enzyme cleaves several growth factors, extracellular matrix molecules and is implicated in some of the same diseases as MIF. We show that the function of the binding between MIF and HTRA1 is to inhibit the proteolytic activity of HTRA1, modulating the availability of molecules that can change cell growth and differentiation. MIF is therefore the first endogenous inhibitor ever found for HTRA1. It was found that both molecules were present in astrocytes and that the functional binding has the ability to modulate astrocytic activities important in development and disease of the CNS.

http://ift.tt/2ygGn0B

The Fascia Iliaca Block as the Primary Intraoperative Anesthesia for Hip Fracture Surgery: A Preliminary Study

Abstract

Background

Early surgical intervention for hip fractures in the elderly has proven efficacious. However, surgical delays commonly occur in this patient population due to comorbid conditions that put these patients at a high risk for hypotension-related complications of general or neuraxial anesthesia or anticoagulants that delay the safe use of neuraxial anesthesia.

Questions/Purposes

The questions/purposes of this study are (1) to investigate if a fascia iliaca block in conjunction with light to moderate sedation could provide adequate analgesia throughout open surgery for intertrochanteric hip fractures (AO/OTA 31-1) without requiring conversion to general anesthesia with airway support and (2) to assess its perioperative complication profile.

Methods

A retrospective chart review was conducted to identify patients with intertrochanteric hip fractures who underwent anesthesia with a fascia iliaca block over a 1.5-year period.

Results

In the six patients identified, there were no intraoperative conversions to general anesthesia requiring airway support. Additionally, there were no intraoperative complications, no mortalities within 30 days, 2 patients on anticoagulation who required a blood transfusion, and a single patient who developed a postoperative hospital-acquired pneumonia that resolved with an antibiotic course.

Conclusions

In this series of patients, we demonstrate that a fascia iliaca block can reliably be utilized as the primary anesthetic for patients undergoing surgical fixation of intertrochanteric hip fractures, with an acceptable perioperative complication profile. Although concomitant sedation was provided with the block, this anesthesia strategy has the potential to reduce preoperative delays and minimize the overall burden of sedative and anesthetic medications in a geriatric population. These initial findings may serve as a basis for future, higher-quality prospective and comparative studies.

http://ift.tt/2iiIS7X

Emergency Management of Sigmoid Colon Volvulus in a Volvulus Belt Population and a Review of Literature

Abstract

Algorithm for management of acute sigmoid volvulus is still controversial. This study was undertaken in a volvulus belt population emphasizing on emergency resection and primary anastomosis without on-table colonic irrigation or diversion. Four hundred forty-five acute sigmoid volvulus patients were reviewed retrospectively. Records of 366 operated patients were studied thoroughly. After operative detorsion and simple decompression, resection and primary anastomosis without a diverting stoma with postoperative anal dilatation were done in those who obeyed certain criteria; the rests were subjected for alternative operations. Ileal resection anastomosis was added in compound volvulus cases. Literature was reviewed. Epidemiology: constitutes 40.4% of small and large intestinal and 87.8% of large intestinal obstruction cases; maximum of 40–60 years with slight male preponderance. Operated: 148 gangrenous, 10 compound, 3 perforated, and 205 uncomplicated patients—mesocoloplasty in 2; resection with primary anastomosis in 270 including 60 gangrenous, 6 compound, and 1 perforated; 92 Hartmann's procedure and 2 Paul Mickulicz in other gangrenous cases. Mortality: with primary anastomosis 7.4% with no significant difference between gangrenous and non-gangrenous groups; with no restoration of continuity 19.2% and overall 7.5% without gangrene, 14.3% with gangrene and 10.4% in an average; in reducing trend with ICU facility. There was no death with compound volvulus. Morbidity with primary anastomosis: 5.9% anastomotic leak, 9.6% wound infection, and 1% wound dehiscence. Emergency resection and primary anastomosis after decompression without on-table lavage are safe procedures in developing nations in patients who are stable at presentation or after resuscitation having favorable intraoperative criteria.

http://ift.tt/2hrFRlS

A Novel ZnONPs/PVA-Functionalized Biomaterials for Bacterial Cells Immobilization and its Strengthening Effects on Quinoline Biodegradation

Abstract

A novel bacterial cells immobilized carrier (ZnONPs/PVA), polyvinyl alcohol (PVA) composites decorated with ZnO nanoparticles (ZnO NPs), was prepared and used for immobilization of the strain Ochrobactrum sp. LC-1, and subsequently for quinoline degrading in water. Characterization of ZnONPs/PVA by using X-ray diffractometer and scanning electron microscopy demonstrated that ZnO NPs were coated on the surface of PVA cubes evenly and the bacterium grew well on the ZnONPs/PVA. Quinoline biodegradation results showed that the degradation effect of quinoline by ZnONPs/PVA immobilized cells was superior to the free cells significantly. The structure and physical properties of ZnNPs/PVA were maintained steady after the reuse of ZnNPs/PVA for cells immobilization several times. Reusability of the ZnONPs/PVA immobilized cells revealed that the quinoline removal ratio was above 97% within 8 h under the conditions of pH neutral, 37 °C when the initial quinoline concentration was 300 mg/L.

http://ift.tt/2A3EMso

Rapid Improvement of Pulmonary Functions in Children After Transcatheter Closure of an Atrial Septal Defect

Abstract

There are very few studies in the literature on respiratory system functions and complications of children with an atrial septal defect (ASD). The aim of this study is to investigate the pulmonary functions and pulmonary complications before and after transcatheter closure in children with an ASD. In this study, pulmonary function test parameters of 30 ASD patients between 5 and 18 years of age who were eligible to be treated by transcatheter ASD closure were compared with 30 healthy children. The patients undergoing transcatheter ASD closure received pulmonary function tests (PFT) at baseline (1 day before ASD closure), and 3 months after the procedure. Forced vital capacity (FVC), forced expired volume in 1 s (FEV1), peak expiratory flow, and mean forced expiratory flow during the middle half of FVC were measured. The mean age of the 30 ASD patients was 9.59 ± 3.1 years; and 20 (66.6%) were female and 10 (33.3%) were male. The mean age of the control group was 10.15 ± 2.21 years, and 19 (63.3%) were girls and 11 (36.6%) were males. ASD patients had significantly reduced FVC (73.11 ± 24.6%; 86.05 ± 26.1; p = 0.001, respectively), and FEV1 (81.34 ± 26.2% and 99.2 ± 19.6%; p = 0.001; respectively) at baseline. But significant improvement was observed in FVC values in the 3^rd-month post-closure comparison of the patient group with the control group (73.11 ± 24.6%; and 88.36 ± 14.5%; p = 0.01, respectively); FEV1 values (81.34 ± 26% and 99.54 ± 18.2%; p = 0.005, respectively) and mean forced expiratory flow between 25 and 75% of vital capacity (MEF25–75) values (94.6 ± 33.4% and 124.2 ± −24.1%; p = 0.01, respectively) were also improved. There was no statistically significant relationship between the PFT measurements at baseline and after closure of the defect and age at transcatheter closure, gender, body height, body weight, ASD diameter, Q _p/Q _s, right ventricle systolic pressure, or mean pulmonary artery pressure values. At the 3^rd month of ASD closure, there was no significant difference in the comparison of the PFT values of the patient and control group. Disturbance in the significant flow limitation of the peripheral airway of ASD patients was observed with PFT. Better pulmonary outcomes were observed in ASD patients after transcatheter closure.

http://ift.tt/2lz6YjJ

Oxidation Reduction Potential (ORP) is Predictive of Complications Following Pediatric Cardiac Surgery

Abstract

Oxidation reduction potential (ORP) or Redox is the ratio of activity between oxidizers and reducers. Oxidative stress (OS) can cause cellular injury and death, and is important in the regulation of immune response to injury or disease. In the present study, we investigated changes in the redox system as a function of cardiopulmonary bypass (CPB) in pediatric patients. 664 plasma samples were collected from 162 pediatric patients having cardiac surgery of various CPB times. Lower ORP values at 12 h post-CPB were associated with poor survival rate (mean ± SD 167 ± 20 vs. 138 ± 19, p = 0.005) and higher rate of thrombotic complications (153 ± 21 vs. 168 ± 20, p < 0.008). Similarly, patients who developed infections had lower ORP values at 6 h (149 ± 19 vs. 160 ± 22, p = 0.02) and 12 h (156 ± 17 vs. 168 ± 21, p = 0.004) post-CPB. Patients that developed any post-operative complication also had lower 6 h (149 ± 17 vs. 161 ± 23, p = 0.002) and 12 h (157 ± 18 vs. 170 ± 21, p = 0.0007) post-CPB ORP values. Free hemoglobin and IL-6, IL-10, and CRP were not associated with ORP levels. However, higher haptoglobin levels preoperatively were protective against decreases in ORP. Decreased ORP is a marker for poor outcome and predictive of post-operative thrombosis, infection, and other complications in critically ill pediatric cardiac surgery patients. These results suggest that redox imbalance and OS may contribute to the risk of complications and poor outcome in pediatric CBP patients. Haptoglobin may be a marker for increased resilience to OS in this population.

http://ift.tt/2yh9zVv

Usefulness of Routine Coronary CT Angiography in Patients with Transposition of the Great Arteries After an Arterial Switch Operation

Abstract

Coronary complications in patients with transposition of the great arteries (TGA) after an arterial switch operation (ASO) are relatively rare, but of all the possible postoperative adverse events, they are potentially the most dangerous. The fate of the coronary arteries, which are transplanted during the neonatal ASO, remains uncertain. There is also no consensus regarding their postoperative evaluation, especially in asymptomatic patients. The aim of this study was to present the early results of routinely performed coronary computed tomography angiography (CCTA) in asymptomatic adolescents and young adults with TGA after an ASO. An initial series of 50 CCTAs performed in asymptomatic patients with TGA after an ASO were evaluated. In each case, a detailed examination of the coronary anatomy, its relationship to the surrounding structures, its exact position in the neoaortic sinus, and the presence of significant coronary abnormalities was performed. The CT scans revealed significant coronary abnormalities in 12 asymptomatic patients: three had acute proximal angulation and stenosis, four had an intra-arterial course, seven had a muscular bridge, one had a left anterior descending artery with an intramuscular course, and one had coronary fistulas to the pulmonary arteries. Additionally, in 25 patients, proximal acute angulation of at least one coronary artery was detected, and four of them had a high ellipticity index. Most of the potentially severe anatomical features were related to the left coronary artery or the left anterior descending artery. CCTA routinely performed on asymptomatic patients with TGA after an ASO provides accurate and useful information for postoperative management. The frequency of coronary anomalies and potentially dangerous anatomical features in this group of patients is high, and their impact on postoperative follow-up remains unknown.

http://ift.tt/2lyLweF

Calcium–axonemal microtubuli interactions underlie mechanism(s) of primary cilia morphological changes

Abstract

We have used cell culture of astrocytes aligned within microchannels to investigate calcium effects on primary cilia morphology. In the absence of calcium and in the presence of flow of media (10 μL.s⁻¹) the majority (90%) of primary cilia showed reversible bending with an average curvature of 2.1 ± 0.9 × 10⁻⁴ nm⁻¹. When 1.0 mM calcium was present, 90% of cilia underwent bending. Forty percent of these cilia demonstrated strong irreversible bending, resulting in a final average curvature of 3.9 ± 1 × 10⁻⁴ nm⁻¹, while 50% of cilia underwent bending similar to that observed during calcium-free flow. The average length of cilia was shifted toward shorter values (3.67 ± 0.34 μm) when exposed to excess calcium (1.0 mM), compared to media devoid of calcium (3.96 ± 0.26 μm). The number of primary cilia that became curved after calcium application was reduced when the cell culture was pre-incubated with 15 μM of the microtubule stabilizer, taxol, for 60 min prior to calcium application. Calcium caused single microtubules to curve at a concentration ≈1.0 mM in vitro, but at higher concentration (≈1.5 mM) multiple microtubule curving occurred. Additionally, calcium causes microtubule-associated protein-2 conformational changes and its dislocation from the microtubule wall at the location of microtubule curvature. A very small amount of calcium, that is 1.45 × 10¹¹ times lower than the maximal capacity of TRPPs calcium channels, may cause gross morphological changes (curving) of primary cilia, while global cytosol calcium levels are expected to remain unchanged. These findings reflect the non-linear manner in which primary cilia may respond to calcium signaling, which in turn may influence the course of development of ciliopathies and cancer.

http://ift.tt/2zTfegI

Small gold nanoparticles presenting linear and looped Cilengitide analogues as radiosensitizers of cells expressing α ν β 3 integrin

Abstract

This work uses linear and looped RGDfV sequences attached to the surface of small (1.8 nm in diameter) gold nanoparticles (AuNPs) to enhance the radiosensitizating effects of Cilengitide, a cyclic RGDf (NMe)V pentapeptide that targets α_vβ₃ integrin which is overexpressed in certain cancers. Following synthesis and purification, the AuNPs were evaluated in vitro against HUVEC, H460, and MCF7 cells in clonogenic assays using a ¹³⁷Cs irradiator. Untargeted AuNPs induced no significant dose enhancement factors (DEFs) in any of the cell types when compared to radiation treatment alone, whereas all evaluated AuNPs functionalized with targeting peptides performed at least as well as controls (irradiation after Cilengitide treatment). The observed DEFs also suggest that cyclizing the linear peptides into more spatially constrained, looped structures may facilitate target binding. These greater dose enhancements merit future in vivo studies of drug-AuNP conjugates to assess the ability of the nanostructures to provide an improved therapeutic benefit over treatment with drug candidates and radiation alone.

Graphical abstract

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http://ift.tt/2yZEtB1

Annealing or direct synthesis of uniform inorganic nanoparticles using salt powder as separation medium

Abstract

Uniform nanoparticles have shown to hold great potential in many different fields. As a result, many resources have been devoted to the search for a general synthesis of uniform nanoparticles, which has led to the proliferation of solution-based methods. However, some of these techniques are inherently difficult to scale up and are unable to meet future industry needs. Additionally, since the synthesis temperature of these methods can only go as high as the evaporation point of the solvent, they are not compatible with the high temperatures required to obtain certain desired properties such as high crystallinity. Recently, solventless methods have gained considerable attention since they are relatively fast and require no expensive or toxic solvents. Inorganic salt powder can be used as separation medium to prevent aggregation and sintering by keeping the as-prepared nanoparticles or precursor materials physically separated. This review surveys the use of inorganic salts in solventless techniques for the annealing or direct synthesis of uniform nanoparticles.

Graphical abstract

Fine inorganic salt powder can be used as separation medium to prevent aggregation and sintering by keeping the as-prepared nanoparticles or precursor materials physically separated. The primary advantages of this strategy are its simplicity and the ability to easily scale-up. Additionally, this strategy can use a wider temperature window compared to solution-based syntheses. Lastly, the inorganic salt powder can be separated and reused by washing the final nanomaterials. This review surveys the use of inorganic salts in solventless techniques for the annealing or direct synthesis of uniform nanoparticles.

http://ift.tt/2z13pbf

Spontaneous external biliary fistula arising from an intrahepatic duct

Abstract

A spontaneous external biliary fistula is most commonly a cholecystocutaneous fistula secondary to acute cholecystitis. A fistula arising from an intrahepatic duct is extremely rare. An 87-year-old man presented with swelling of the epigastric region and right upper quadrant abdomen. He had a history of cholecystectomy and endoscopic sphincterotomy. After antibiotic treatment and surgical opening of both lesions, abdominal computed tomography demonstrated a soft tissue mass cephalad to the umbilicus. We excised the mass, and found it to be associated with a fistula through the linea alba. Fistulography showed an abscess cavity communicating with the intrahepatic duct in segment III. Histopathological examination of the mass showed an abscess without malignancy. The fistula closed spontaneously without laparotomy. In this case, the underlying pathology was considered to be associated with a subcapsular hepatic cyst in segment III.

http://ift.tt/2ik0C2D

Contrast-enhanced ultrasonography in clinical practice in Crohn’s disease: feasibility of destruction/replenishment method and software analysis

Abstract

The aim of this Pictorial Essay is to evaluate the feasibility in the clinical practice of CEUS destruction/replenishment method and time intensity curve (TIC) analysis using the available software in patients with Crohn's disease. The ultrasound (US) procedure using contrast agent is briefly described, elaboration and analysis of the US sequences are explained in detail, and some advantages and disadvantages of the method are highlighted. The Authors suggest that the destruction/replenishment method is useful and time-saving in Crohn's disease if multiple measurements are required on intestinal portions adjacent to each other or in different locations.

http://ift.tt/2iOeGFx

A Highly Promiscuous Integron, Plasmids, Extended Spectrum Beta Lactamases and Efflux Pumps as Factors Governing Multidrug Resistance in a Highly Drug Resistant Vibrio fluvialis Isolate BD146 from Kolkata, India

Abstract

In an earlier study from this laboratory, Vibrio fluvialis BD146, a clinical isolate from Kolkata, India, 2002, was found to be resistant to all the fourteen antibiotics tested. It harboured a high copy number plasmid pBD146 and a low copy number plasmid. In the present study, a more detailed analysis was carried out to unravel different resistance mechanisms in this isolate. Sequencing showed that variable region of class 1 integron located on low copy number plasmid harbored arr3-cmlA-bla _OXA10-aadA1 gene cassettes. Analysis for extended spectrum beta lactamases (ESBLs) revealed that BD146 was ESBL positive. Efflux pumps were involved in the drug resistance phenotype for chloramphenicol, kanamycin, streptomycin and tetracycline. Sequence analysis of pBD146 revealed the presence of genes encoding BDint an integrase with a unique sequence having little similarity to other known integrases, toxin–antitoxin (parE/parD), a replicase, trimethoprim resistance (dfrVI) and quinolone resistance (qnrVC5). Presence of cmlA, putative novel integrase and toxin–antitoxin system in V. fluvialis has been documented for the first time in this report. pBD146 showed 99% sequence similarity with pVN84 from V. cholerae O1 of Vietnam, 2004 and a plasmid from V. parahaemolyticus v110 of Hong Kong, 2010. Conjugation experiments proved the ability of pBD146 and the low copy number plasmid, to get transferred to another host imparting their antibiotic resistance traits to the transconjugants. Therefore, present study has indicated that plasmids played an important role for dissemination of drug resistance.

http://ift.tt/2lydsiG

Characteristics of Non-postoperative Pediatric Pericardial Effusion: A Multicenter Retrospective Cohort Study from the Pediatric Health Information System (PHIS)

Abstract

Little is known about the causes and risks of non-postoperative pericardial effusion (PCE) in pediatric patients. We sought to assess the diagnoses most frequently associated with admissions for PCE, and to determine if certain conditions were associated with higher in-hospital mortality and rates of readmission. Nationally distributed data from 44 pediatric hospitals in the 2004–2015 Pediatric Health Information System database were used to identify patients with hospital admissions for International Classification of Disease, Ninth Revision (ICD-9) codes for PCE and/or cardiac tamponade. Children with congenital heart disease were excluded. ICD-9 codes for conditions associated with PCE were grouped into eight categories: neoplastic, renal, autoimmune/inflammatory, pneumonia, viral, bacterial, hypothyroidism, and idiopathic. Multivariable models were used to evaluate odds of in-hospital mortality and readmission within 30 and 90 days. There were 9902 patients who met inclusion criteria. Total in-hospital mortality was 8.2% (n = 813); of those without a neoplastic diagnosis, mortality was 6.5% (n = 493/7543). Idiopathic PCE accounted for the most admissions (36%), followed by neoplasms (24%), pneumonia (20%), and autoimmune/inflammatory disease (19%). In multivariable models, odds of death were highest for neoplasms (adjusted odds ratio 3.83, p < 0.001) and renal disease (adjusted odds ratio 2.86, p < 0.001). Children with a neoplasm, renal disease, and those undergoing pericardiocentesis had the highest rates of readmission at 30 and 90 days. Children admitted with non-postoperative PCE have multiple associated conditions. Neoplasm and renal disease in the setting of PCE are associated with the highest odds of in-hospital mortality among concomitant conditions; children with a neoplasm, renal disease, and those undergoing pericardiocentesis have the highest odds of readmission.

http://ift.tt/2gRqov3

Longer Ischemic Time is Associated with Increased Ventricular Stiffness as Measured by Pressure–Volume Loop Analysis in Pediatric Heart Transplant Recipients

Abstract

Background

The purpose of this study was to investigate the associations between clinical factors and cardiac function as measured by pressure–volume loops (PVLs) in a pediatric heart transplant cohort.

Methods

Patients (age < 20 years) who underwent heart transplantation presenting for a clinically indicated catheterization were enrolled. PVLs were recorded using microconductance catheters (CD Leycom^®, Zoetermeer, Netherlands). Demographic data, serum B-type natriuretic peptide (BNP), time from transplant, ischemic time, presence of transplant coronary artery disease, donor-specific antibodies, and history of rejection were recorded at the time of catheterization. PVL data included contractility indices: end-systolic elastance and preload recruitable stroke work; ventricular–arterial coupling index; ventricular stiffness constant, Beta; and isovolumic relaxation time constant, tau. Associations between PVL measures and clinical data were investigated using non-parametric statistical tests.

Results

A total of 18 patients were enrolled. Median age was 8.7 years (IQR 5–14 years). There were ten males and eight females. Six patients had a history of rejection and ten had positive donor-specific antibodies. There was no transplant coronary artery disease. Median BNP was 100 pg/mL (IQR 46–140). Time from transplant to PVL obtained during catheterization procedure was 4.1 years (IQR 1.7–7.8 year). No single clinical characteristic was statistically significant when correlated with PVL data. However, longer ischemic time was associated with worse Beta (r = 0.49, p = 0.05).

Conclusions

Our study found that longer ischemic times are associated with increased left ventricular stiffness. No other single clinical variable is associated with cardiac dysfunction as determined by PVL analysis.

http://ift.tt/2ijPsLh

Modulatory effects of alpha-lipoic acid (ALA) administration on insulin sensitivity in obese PCOS patients

Abstract

Purpose

To evaluate the efficacy of alpha-lipoic acid (ALA) administration on hormonal and metabolic parameters of obese PCOS patients.

Methods

A group of 32 obese PCOS patients were selected after informed consent. 20 patients referred to have first grade relatives with diabetes type I or II. Hormonal and metabolic parameters as well as OGTT were evaluated before and after 12 weeks of ALA integrative administration (400 mg per os every day).

Results

ALA administration significantly decreased insulin, glucose, BMI and HOMA index. Hyperinsulinemia and insulin response to OGTT decreased both as maximal response (Δmax) and as AUC. PCOS with diabetes relatives showed the decrease also of triglyceride and GOT. Interestingly in all PCOS no changes occurred on all hormonal parameters involved in reproduction such as LH, FSH, and androstenedione.

Conclusions

ALA integrative administration at a low dosage as 400 mg daily improved the metabolic impairment of all PCOS patients especially in those PCOS with familiar diabetes who have a higher grade of risk of NAFLD and predisposition to diabetes.

http://ift.tt/2lxqCMR

Reply to Comment to: long-term retromuscular and intraperitoneal mesh size changes within a randomized controlled trial on incisional hernia repair, including a review of the literature. Li Y; Zhang W

http://ift.tt/2zTwLp7

West Syndrome: A Review and Guide for Paediatricians

Abstract

West syndrome (WS), also known as infantile spasms, occurs in infancy with a peak between 4 and 7 months. Spasms, neurodevelopmental regression and hypsarrhythmia on electroencephalogram (EEG) basically define WS. The International League Against Epilepsy commission classifies the aetiologies of WS into genetic, structural, metabolic and unknown. Early diagnosis and a shorter lag time to treatment are essential for the overall outcome of WS patients. These goals are feasible with the addition of brain magnetic resonance imaging (MRI) and genetic and metabolic testing. The present work analysed the medical literature on WS and reports the principal therapeutic protocols of its management. Adrenocorticotropic hormone (ACTH), vigabatrin (VGB) and corticosteroids are the first-line treatments for WS. There is no unique therapeutic protocol for ACTH, but most of the evidence suggests that low doses are as effective as high doses for short-term treatment, which is generally 2 weeks followed by dose tapering. VGB is generally administered at doses from 50 to 150 mg/kg/day, but its related retinal toxicity, which occurs in 21–34% of infants, is most frequently observed when treatment periods last longer than 6 months. Among corticosteroids, a treatment of 14 days of oral prednisolone (40–60 mg/day) has been considered effective and well tolerated. Considering that an early diagnosis and a shorter lag time to treatment are essential for successful outcomes in these patients, further studies on efficacy of the different therapeutic approaches with evaluation of final outcome after cessation of therapy are needed.

http://ift.tt/2z1aF7i

Mechanism of resistance to endocrine therapy in breast cancer: the important role of PI3K/Akt/mTOR in estrogen receptor-positive, HER2-negative breast cancer

Abstract

Endocrine therapy is a crucial treatment for estrogen receptor-positive (ER+) breast cancer, with proven clinical benefits. However, adaptive mechanisms emerge in the tumor, causing resistance to endocrine therapy. A better understanding of resistance mechanisms is needed to overcome this problem and to develop new, precise treatment strategies. Accumulating genetic and cancer biological studies demonstrate the importance of understanding the PI3K/Akt/mTOR and CDK4/6/RB pathways in ER+ HER2− breast cancer. PIK3CA (which encodes phosphatidylinositol-4, 5-bisphosphate 3-kinase catalytic subunit α) is frequently mutated in breast cancer, and 30% of advanced ER+ HER2− breast cancers have an activating PIK3CA mutation. AKT1 mutations (E17K) have been found in 1.4–8% of breast cancer patients. ER+ breast cancer patients preferentially demonstrate gain of CCND1 (cyclin D1; 58% in luminal B vs. 29% in luminal A) and CDK4 (25% in luminal B vs. 14% in luminal A) and loss of CDKN2A (p16) and CDKN2C (p18), which are negatively regulated with the cell cycle and are correlated with the CDK4/6/RB pathway. Abnormalities in PI3K/Akt/mTOR and CDK4/6/RB pathways due to genetic alterations result in deregulated kinase activity and malignant transformation. This review focuses on the recent reports of the essential role of PI3K/Akt/mTOR and CDK4/6/RB pathways in ER+ HER2− breast cancer.

http://ift.tt/2gYiL9L

Dynamical regimes and intracavity propagation delay in external cavity semiconductor diode lasers

Abstract

Intracavity propagation delay, a delay introduced by a semiconductor diode laser, is found to significantly influence synchronization of multiple semiconductor diode lasers, operated either in stable or in chaotic regime. Two diode lasers coupled in unidirectional scheme is considered in this numerical study. A diode laser subjected to an optical feedback, also called an external cavity diode laser, acts as the transmitter laser (TL). A solitary diode laser acts as the receiver laser (RL). The optical output of the TL is coupled to the RL and laser operating parameters are optimized to achieve synchronization in their output intensities. The time-of-flight between the TL and RL introduces an intercavity time delay in the dynamics of RL. In addition to this, an intracavity propagation delay arises as the TL's field propagated within the RL. This intracavity propagation delay is evaluated by cross-correlation analysis between the output intensities of the lasers. The intracavity propagation delay is found to increase as the external cavity feedback rate of TL is increased, while an increment in the injection rate between the two lasers resulted in a reduction of intracavity propagation delay.

http://ift.tt/2zlO6eb

The observer-based synchronization and parameter estimation of a class of chaotic system via a single output

Abstract

Observer-based synchronization and parameter estimation of chaotic systems has been an interesting and important issue in theory and various fields of application. In this paper first we investigate the observer-based synchronization of a class of chaotic systems, and then discuss its parameter estimation via a single output. We assume that only the sum of the first and second state variables is available. By constructing a proper observer, some novel criteria for observer-based synchronization and parameter estimation are proposed via a scalar input. The Lü chaotic system is taken as an example to demonstrate the efficiency of the proposed approach.

http://ift.tt/2iLLoqZ

Emergence and space–time structure of lump solution to the (2 $$+$$ + 1)-dimensional generalized KP equation

Abstract

A periodic breather-wave solution is obtained using homoclinic test approach and Hirota's bilinear method with a small perturbation parameter \(u_{0}\) for the (2 \(+\) 1)-dimensional generalized Kadomtsev–Petviashvili equation. Based on the periodic breather-wave, a lump solution is emerged by limit behaviour. Finally, three different forms of the space–time structure of the lump solution are investigated and discussed using the extreme value theory.

http://ift.tt/2zksHSt

Menstrual cycle characteristics and steroid hormone, prolactin, and growth factor levels in premenopausal women

Abstract

Purpose

Menstrual cycle characteristics are markers of endocrine milieu. However, associations between age at menarche and adulthood sex steroid hormone levels have been inconsistent, and data on menstrual characteristics and non-sex steroid hormones are sparse.

Methods

We assessed the relations of menstrual characteristics with premenopausal plasma sex steroid hormones, sex hormone binding globulin (SHBG), prolactin, and growth factors among 2,745 premenopausal women (age 32–52) from the Nurses' Health Study II. Geometric means and tests for trend were calculated using multivariable general linear models.

Results

Early age at menarche was associated with higher premenopausal early-follicular free estradiol (percent difference < 12 vs. > 13 years = 11%), early-follicular estrone (7%), luteal estrone (7%), and free testosterone (8%) (all p _trend < 0.05). Short menstrual cycle length at age 18–22 was associated with higher early-follicular total (< 26 vs. > 39 days = 18%) and free estradiol (16%), early-follicular estrone (9%), SHBG (7%), lower luteal free estradiol (− 14%), total (− 6%), and free testosterone (− 15%) (all p _trend < 0.05). Short adult menstrual length was associated with higher early-follicular total estradiol (< 26 vs. > 31 days = 14%), SHBG (10%), lower luteal estrone (− 8%), progesterone (− 9%), total (− 11%) and free testosterone (− 25%), and androstenedione (− 14%) (all p _trend < 0.05). Irregularity of menses at 18–22 was associated with lower early-follicular total (irregular vs. very regular = − 14%) and free estradiol (− 14%), and early-follicular estrone (− 8%) (All p _trend < 0.05). Irregularity of adult menstrual cycle was associated with lower luteal total estradiol (irregular vs. very regular = − 8%), SHBG (− 3%), higher total (8%), and free testosterone (11%) (all p _trend < 0.05).

Conclusions

Early-life and adulthood menstrual characteristics are moderately associated with mid-to-late reproductive year's hormone concentrations. These relations of menstrual characteristics with endogenous hormone levels could partially account for associations between menstrual characteristics and reproductive cancers or other chronic diseases.

http://ift.tt/2z6bz23

Association between chronic inflammation and latent infection of Propionibacterium acnes in non-pyogenic degenerated intervertebral discs: a pilot study

Abstract

Purpose

Propionibacterium acnes may be considered a new pathogeny for disc degeneration, but its pathological role has remained unclear. This study was designed to determine whether the latent infection of P. acnes was associated with chronic inflammation in degenerated intervertebral discs via quantification of the levels of a series of cytokines and neutrophils.

Methods

Here, 76 degenerated intervertebral discs were harvested from patients with lower back pain and/or sciatica. Discs with and without P. acnes infection were distinguished and identified using anaerobic culture combined with 16S rDNA PCR and histological examination. Then, cytokines of TNF-α, IL-1β, IL-6, IL-8, MCP-1, MIP-1α, and IP-10, and the numbers of neutrophils were quantified and compared. The severity of disc degeneration and the prevalence of Modic changes were also evaluated between discs with and without P. acnes.

Results

After anaerobic culture and PCR examination, 15 intervertebral discs were placed in the P. acnes-positive group. Another 15 discs were selected from the remaining bacteria-free samples and formed a matched P. acnes-negative group. IL-8, MIP-1α, MCP-1, IP-10, TNF-α, and neutrophils were much higher in P. acnes-positive group than that in the matched P. acnes-negative group. However, only IL-8, MIP-1α, and neutrophils were statistically significant. Furthermore, 7 of 15 P. acnes-positive samples were histologically positive and a subgroup analysis suggested that both histological and PCR-positive samples had the highest concentrations of cytokines of IL-8, MIP-1α, TNF-α, and MCP-1 and the greatest numbers of neutrophils. PCR-positive but histologically negative samples showed the second-greatest, and matched P. acnes-negative samples showed the fewest. However, the difference was only statistically significant between samples found positive under both histology and PCR and samples found negative for P. acnes. Finally, P. acnes-positive group had significantly lower height of intervertebral discs and there was a trend with higher proportion of Modic changes in P. acnes-positive group, but without statistical results.

Conclusions

Latent P. acnes infection was associated with chronic inflammation in degenerated intervertebral discs, especially in the samples with visible bacteria in histology, which manifested as increased numbers of cytokines and neutrophils. Discs with P. acnes infection had much severer disc degeneration and P. acnes-associated chronic inflammation may be the reason.

http://ift.tt/2z1o78P

Slice-accelerated gradient-echo echo planar imaging dynamic susceptibility contrast-enhanced MRI with blipped CAIPI: effect of increasing temporal resolution

Abstract

Purpose

To assess the influence of high temporal resolution on the perfusion measurements and image quality of perfusion maps, by applying simultaneous-multi-slice acquisition (SMS) dynamic susceptibility contrast-enhanced (DSC) magnetic resonance imaging (MRI).

Materials and methods

DSC-MRI data using SMS gradient-echo echo planar imaging sequences in 10 subjects with no intracranial abnormalities were retrospectively analyzed. Three additional data sets with temporal resolution of 1.0, 1.5, and 2.0 s were created from the raw data sets of 0.5 s. Cerebral blood flow (CBF), cerebral blood volume, mean transit time (MTT), time to peak (TTP), and time to maximum tissue residue function (T _max) measurements were performed, as was visual perfusion map analysis. The perfusion parameter for temporal resolution of 0.5 s (reference) was compared with each synthesized perfusion parameter.

Results

CBF, MTT, and TTP values at temporal resolutions of 1.5 and 2.0 s differed significantly from the reference. The image quality of MTT, TTP, and T _max maps deteriorated with decreasing temporal resolution.

Conclusion

The temporal resolution of DSC-MRI influences perfusion parameters and SMS DSC-MRI provides better image quality for MTT, TTP, and T _max maps.

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Drug-induced anaphylaxis in China: a 10 year retrospective analysis of the Beijing Pharmacovigilance Database

Abstract

Background Few studies on the causes of drug-induced anaphylaxis (DIA) in the hospital setting are available. Objective We aimed to use the Beijing Pharmacovigilance Database (BPD) to identify the causes of DIA in Beijing, China. Setting Anaphylactic case reports from the BPD provided by the Beijing Center for Adverse Drug Reaction Monitoring. Method DIA cases collected by the BPD from January 2004 to December 2014 were adjudicated. Cases were analyzed for demographics, causative drugs and route of administration, and clinical signs and outcomes. Main outcome measure Drugs implicated in DIAs were identified and the signs and symptoms of the DIA cases were analyzed. Results A total of 1189 DIA cases were analyzed. The mean age was 47.6 years, and 732 (61.6%) were aged from 18 to 59 years. A total of 627 patients (52.7%) were females. There was a predominance of cardiovascular (83.8%) followed by respiratory (55.4%), central nervous (50.1%), mucocutaneous (47.4%), and gastrointestinal symptoms (31.3%). A total of 249 different drugs were involved. DIAs were mainly caused by antibiotics (39.3%), traditional Chinese medicines (TCM) (11.9%), radiocontrast agents (11.9%), and antineoplastic agents (10.3%). Cephalosporins accounted for majority (34.5%) of antibiotic-induced anaphylaxis, followed by fluoroquinolones (29.6%), beta-lactam/beta-lactamase inhibitors (15.4%) and penicillins (7.9%). Blood products and biological agents (3.1%), and plasma substitutes (2.1%) were also important contributors to DIAs. Conclusion A variety of drug classes were implicated in DIAs. Patients should be closely monitored for signs and symptoms of anaphylaxis when medications are administered especially with antibiotics, TCM, radiocontrast and antineoplastic agents.

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Addressing the global need for public health clinical pharmacists through student pharmacist education: a focus on developing nations

Abstract

It is time for pharmacists to begin advancing their roles in public health and play a more integral part in public health initiatives. Within developed nations, the profession has demonstrated its value in advancing preventive care; however, the same cannot be said for pharmacists worldwide. Emphasis on training public health pharmacists should also be on developing nations, where the need for preventive care is highly unmet. To ensure all graduating pharmacists are prepared to engage in public health activities, education in this field must be provided during their main years of pharmacy school. In conclusion, public health education should be incorporated into pharmacy curriculae within developing nations so all pharmacy graduates are prepared to engage in public health activities.

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Exposure to anticholinergic and sedative medicines as indicators of high-risk prescriptions in the elderly

Abstract

Background There are several assessment scales to evaluate the risk of falls or the adverse drug reaction risk. Few are sufficiently specific to assess the impact of drug prescriptions on falls in geriatric populations. Objective To define the risk of anticholinergic and sedation-related ADRs in an elderly hospitalized patient population using the Drug Burden Index (DBI), Anticholinergic Drug Scale (ADS), and Sedative Load Model (SLM). Setting Five geriatric university hospital centers in France. Method Multicenter prospective cohort study from 2011 to 2013. Drug prescriptions were compiled to estimate anticholinergic and sedative exposure. Any associations between the drug scales and falls were assessed. Main outcome measure Drug exposure estimated with the DBI, ADS, and SLM scales. Results 315 patients, with a mean age of 87 years and 117 documented falls, were included from 5 geriatric hospitals. Sixty-one percent of these patients had a DBI > 0, 20.3% had an ADS ≥ 3, 56.2% a SLM > 0. No association was detected between the scores and the risk of a fall (p > 0.05). Factors significantly associated with a risk of a fall were: a prior history of a fall in the previous 12 months (adjusted odds ratio [aOR] = 7.24, 4.06–12.89), orthostatic hypotension ([aOR] = 2.84; 1.39–5.79), or prescription of antidepressants ([aOR] = 2.12; 1.17–3.84). Conclusion A specific scale to identify high-risk prescriptions would help clinicians and pharmacists to optimize therapeutic treatments for the elderly. In light of the multifactorial characteristics of falls, predicting their risk should be based on a well-defined set of factors.

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A successful case of locally advanced pancreatic cancer undergoing curative distal pancreatectomy with en bloc celiac axis resection after combination chemotherapy of nab-paclitaxel with gemcitabine

Abstract

Pancreatic cancer patients have a poor prognosis because of a low rate of resection that results from distant metastases or local advancement. We report a successful case of unresectable locally advanced pancreatic cancer in a patient who was curatively resected after combination therapy with nab-paclitaxel (nab-PTX) and gemcitabine (GEM). A 61-year-old man was referred for treatment of a 45-mm pancreatic tail tumor involving the celiac axis, common hepatic artery, and splenic artery that appeared as an abnormal soft-density mass on imaging. This patient's tumor was defined as unresectable due to local advancement, and, therefore, the powerful combined chemotherapy regimen of nab-PTX with GEM was initiated to allow for possible resection later. After three cycles of chemotherapy, a CT scan revealed that the soft-density mass around the celiac axis and common hepatic artery had dramatically disappeared, and the tumor was then determined to be a resectable lesion. Thus, distal pancreatectomy with en bloc celiac axis resection was performed and curability was achieved. There has been no tumor recurrence or distant metastasis at more than 12 months after surgery, and the patient remains alive at 17 months after initial chemotherapy.

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Grading system for migrated lumbar disc herniation on sagittal magnetic resonance imaging: an agreement study

Abstract

Purpose

Migrated lumbar disc herniations (LDHs) in the sagittal plane are common. Disc migration grading can be applied as a useful measurement tool in the diagnosis, treatment, and outcome evaluation of migrated LDH. No study has evaluated the reliability of migrated LDH grading. We evaluated the reliability and functionality of the current magnetic resonance imaging (MRI) grading system for migrated LDH.

Methods

We assessed a six-level grading system developed based on sagittal MRI and graded according to the direction (rostral and caudal) and degree (low, high, and very high) of disc migration. One-hundred and one migrated LDHs treated with minimally invasive endoscopic discectomy were analyzed independently by two experienced radiologists. Intraobserver and interobserver agreements were assessed by kappa statistics.

Results

The most common migrated LDH grade was grade 4 (30.94%; caudal, low-grade migration). Rostral and caudal migrations were more common in the upper and lower lumbar levels, respectively. Interobserver agreement in the grading of migrated LDH was good at both the first (kappa = 0.737) and second assessment (kappa = 0.657). The intraobserver agreement for reader 1 was very good (kappa = 0.827) and for reader 2 was good (kappa = 0.620).

Conclusions

The current grading system for migrated LDH was found to be reliable and functional with good interobserver and intraobserver agreement. It may be useful in the interpretation of disc migration patterns and outcomes of various minimally invasive surgical procedures.

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The association between collagen gene polymorphisms and intracranial aneurysms: a meta-analysis

Abstract

The association between single nucleotide polymorphisms (SNPs) of the collagen gene and intracranial aneurysm (IA) pathogenesis remains controversial. Thus, in this study, a meta-analysis was performed to evaluate the association between collagen gene SNPs and the incidence of IA. A systematic search of major online databases up to March 2017 was performed. Five genetic models (allelic, dominant, recessive, heterozygous, and homozygous models) were used to analyze the associations. A total of 14 trials with 13,709 patients were included. Four collagen genes, COL1A2 (21 SNPs), COL3A1 (7 SNPs), COL4A1 (6 SNPs), and COL4A2 (1 SNP), were analyzed. We observed that rs42524 in the COL1A2 gene was associated with a significant increase in the risk of IA in Japanese patients (allelic model: OR, 1.94; 95% CI, 1.03–3.64; p = 0.04); the rs1800255 polymorphism in the COL3A1 gene was significantly correlated with Chinese IA patients (allelic model: OR, 1.50; 95% CI, 1.30–1.73; p < 0.001); and rs2621215 was significantly correlated with IA for the heterozygous model (OR, 1.58; 95% CI, 1.15–2.17; p = 0.005) and the dominant model (OR, 1.49; 95% CI, 1.09–2.02; p = 0.012). Furthermore, in the COL4A1 gene, there was a significant relationship between the rs3783107 polymorphism and a Dutch IA population (allelic model: OR, 1.23; 95% CI, 1.06–1.42; p = 0.006), and the prevalence ratio of mutation carriers in the Dutch population was significantly higher than that in the Japanese population (ROR, 1.31; 95% CI, 1.07–1.63; p = 0.008). The rs1800255 polymorphism in COL3A1 is robustly correlated with IA in the Chinese population. Three COL1A2 SNPs—rs42524, rs1800238, and rs2621215—should be studied further.

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Unnecessary preoperative biliary drainage: impact on perioperative outcomes of resectable periampullary tumors

Abstract

Objective

Routine preoperative endoscopic biliary drainage (PEBD) is not recommended for malignant periampullary tumors (MPT) with uncomplicated obstructive cholestasis, yet many patients still receive routine PEBD. Herein were assessed perioperative outcomes of routine PEBD in resectable MPT with uncomplicated biliary obstruction.

Methods

From 2008 to 2014, we identified three groups among patients undergoing surgery for resectable MPT: "unnecessary-PEBD" (despite recommendations), "necessary-PEBD" (following recommendations), and "upfront-surgery groups." The first two groups were compared on referral patterns, drainage procedure, and post-PEBD complications; "Unnecessary-PEBD" and "upfront-surgery" groups were compared on perioperative outcomes.

Results

A total 140 patients underwent surgery for resectable MPT; 38 had cholestasis with clear PEBD indication ("necessary-PEBD"). A further 66 presented uncomplicated obstructive cholestasis with total bilirubin < 300 μmol/l, of whom 26 had unnecessary PEBD and 40 underwent upfront surgery. In total, 40.1% of PEBD were unnecessary and 64.1% were performed before surgical consultation. Time-to-surgery was significantly increased in the "unnecessary-PEBD" group by a mean ± SD 35.3 ± 5.5 days as compared to "upfront-surgery" group (95%CI [24.4–46.2]; p < 0.001). The "unnecessary-PEBD" group had a post-PEBD complication rate of 34.6%, and 7.7% were unresectable due to severe fibrosis following PEBD-induced acute pancreatitis. Perioperative severe complication rate was higher in the "unnecessary-PEBD" (73.1%) than in the "upfront-surgery" group (37.5%, p = 0.005), as was Clavien-Dindo grade > II post-operative complication rate (65.4 and 37.5%; p = 0.03).

Conclusion

Routine preoperative biliary drainage is associated with an increased morbidity and persists despite recommendations against its systematic use. Early multidisciplinary team discussions with pancreatic surgeons should be implemented with an aim to reduce unnecessary stenting and improve patient outcomes.

http://ift.tt/2hpC74s

Enhancing the grafting amount of Poly(ε-caprolactone) on MgO nanoparticles by modifying with ethylene glycol for improving mechanical properties of Poly(ε-caprolactone)

Abstract

A new surface modification method to improve the graft polymerization of ε-caprolactone (CL) on MgO surface was developed. The MgO nanoparticles were first modified with ethylene glycol (EG), and then used for initiating graft polymerization of CL. The modified MgO nanoparticles were attested by fourier transform infrared spectroscopy, thermal gravimetric analysis and dispersion stability test. The results showed that EG was successfully grafted onto the MgO surface, the hydroxyl group of the grafted EG initiated the graft polymerization of CL onto the MgO surface in the presence of stannous octanoate. The PCL grafting amount (11.13%) on MgO modified with EG (MgO-EG) is much higher than that of unmodified MgO (3.95%). MgO-EG-PCL with 11.13 wt% of grafted PCL exhibited the most excellent dispersibility in chloroform. The MgO-EG-PCL/PCL composites exhibited the most significant improvement, tensile strength and the elongation at break of PCL increased from 15.64 to 19.58 MPa and from 272.34% to 420.73%, respectively.

http://ift.tt/2yi6sfC

Assessing species climatic requirements beyond the realized niche: some lessons mainly from tree species distribution modelling

Abstract

Almost all climate change studies of plants and animals adopt an 'equilibrium assumption' that analyses of natural distributions provide reliable estimates of species climatic requirements. Yet commercial forestry trials around the world have shown that many tree species can grow successfully under climatic conditions somewhat different from those of their natural distributions. Under climate change it is reasonable to assume that a long-lived tree species, already well-established at particular sites, may be able to display some of the climatic adaptability shown in trials outside its natural distribution. The purpose of this paper is to outline how some species distribution modelling (SDM) and ecological niche modelling (ENM) studies have estimated species climatic requirements beyond those shown by conventional analyses of just their natural distributions, and to show how recent developments are facilitating these analyses. Some of the earliest SDM studies of trees demonstrated the desirability of assessing species climatic requirements using data from outside, as well as within, their natural distributions. In recent years, with the advent of large biodiversity databases and some revised SDM analysis methods, there has been a revival of interest in measuring species climatic requirements using data from beyond their realized niches. It is recommended that at least for tree species, natural distribution data, and where possible results from plantings beyond natural distributions, should be analysed in climate change studies. When this is not possible, some alternative methods of estimating species climatic requirements are identified and some of their advantages and disadvantages are considered.

http://ift.tt/2yZfN9k

Study on the effect of linear alkyl [CH 2 CH 2 ] m and ether [CH 2 CH 2 O] m groups in the α,ω-hydroxy telechelic poly(L-lactide) (HOPLLAOH) and their poly(ester-urethanes) (PEUs). Synthesis and Characterization

Abstract

α,ω-Hydroxy telechelic poly(L-lactides) (HOPLLAOH) were synthesized by ring-opening polymerization of the L-lactide (L-LA) catalyzed by tin octoate [Sn(Oct)₂] in the presence of two different types of initiators such as alkyl diols [HO−(CH₂−CH₂)_m−OH] and ether diols [HO−(CH₂−CH₂−O)_m−H] (where m = 2, 3, 4, 5, 6, and 8), and eventually, two different families of HOPLLAOH where the alkyl group (AG) [HO−PLLA−(CH₂−CH₂)_m−PLLA−OH (HOPLLA_aOH)] and ether group (EG) [HO−PLLA−(CH₂−CH₂−O)_m−PLLA−OH (HOPLLA_eOH)] are part of the backbone of the polymer with a systematic increase in these segments were synthesized. The number average molecular weight (M _n) for all samples were similar [M _n(NMR) = 1610–1980]. The weight percent (wt.%) of AG and EG had a dramatic effect on the glass transition temperature (T _g) of HOPLLA_aOH (from 19 to 3 °C) and HOPLLA_eOH (from 19 to −1 °C), respectively, where the wt.% of AG or EG induced a decrease on the T _g with a relationship that was inversely proportional. For poly(ester-urethanes) (PEUs) derived from HOPLLA_aOH (PEU_a) and HOPLLA_eOH (PEU_e) and 1,6-hexamethylene diisocyanate (HDI) showed an increase in the values of T _g attributed to the hydrogen bonding of the urethanes groups in the main chain, for example from 19 (HOPLLA_4aOH) to 39 °C (PEU_4a) where 4a is indicating four aliphatic methylenes. However, the systematic variation in the repetitive unit from AG and EG in the PEU_a and PEU_e, respectively, it had also the similar effect on the T _g, decreasing the values, for example, PEU_a from 39 to 19 °C and PEU_e from 39 to 17 °C, consistently as such as the previous HOPLLAOH species.

http://ift.tt/2iLbBWP

Exploring the Repeated Name Penalty and the Overt Pronoun Penalty in Spanish

Abstract

Anaphoric expressions such as repeated names, overt pronouns, and null pronouns serve a major role in the creation and maintenance of discourse coherence. The felicitous use of an anaphoric expression is highly dependent on the discourse salience of the entity introduced by the antecedent. Gordon et al. (Cogn Sci 17:311–347, 1993) showed that, in English, sentences containing repeated names were read more slowly than corresponding sentences containing pronouns when the antecedent of the anaphoric expression was the subject of the previous sentence. This effect was dubbed the Repeated Name Penalty (RNP), and it was further found that this processing delay is eliminated if the antecedent of the anaphoric expression is the object of the previous sentence. The RNP was later extended to Mandarin Chinese (Yang et al. in Lang Cogn Process 14:715–743, 1999) and to Spanish (Gelormini-Lezama and Almor in Lang Cogn Process 26(3):437–454, 2011), which suggests that this might be a universal phenomenon. Moreover, the Spanish results showed an additional effect: sentences containing overt pronouns were read more slowly than corresponding sentences containing null pronouns when the antecedent of the anaphoric expression was the subject of the previous sentence. This effect was dubbed the Overt Pronoun Penalty (OPP) and, like the original RNP, the effect is also eliminated if the antecedent is in object position (Gelormini-Lezama and Almor 2011; Gordon et al. 1993). The similarity of the RNP and the OPP in Spanish suggests that these two processing phenomena might be caused by the same underlying principles. This paper is a critical review of the literature on these processing delays in Spanish and an attempt to integrate the data in a unified framework. Specifically, and following pragmatic explanations like the Informational Load Hypothesis (Almor in Psychol Rev 106:748–765, 1999), the RNP and OPP in Spanish can be understood as superficial manifestations of an imbalance between processing cost and discourse function.

http://ift.tt/2hoFHvP

Synthesis of novel copolymer based on precipitation polymerization and its application in positive-tone photoresist

Abstract

A series of copolymers Poly (TBA-CA-St-ASM)(PTCSA) were synthesized via precipitation polymerization by using tert-Butyl acrylate (TBA), Styrene (St), p-acetoxy styrene (ASM), and cedryl methacrylate (CA) as co-monomer. Then, Poly (TBA-CA-St-HS)(PTCSH) was prepared in the presence of sodium methoxide in methanol. The fourier transfer infrared (FT-IR) spectra and proton nuclear magnetic resonance (¹H–NMR) spectra indicated that the synthesis was successful. The molecular weight, glass transition temperature (T_g) and thermal decomposition temperature (T(10%)) of the copolymers increased with the addition of CA. Moreover, a positive-tone chemically amplified Krypton Fluoride (KrF) photoresist was prepared, and the photolithography performance of the photoresist was evaluated using a KrF laser exposure system, the result showed that the resolution could reach the level of 0.25 μm.

http://ift.tt/2gXNQdo

Objective assessment of colonoscope manipulation skills in colonoscopy training

Abstract

Objective

Manipulation of the colonoscope is a technical challenge for novice clinicians which is best learned in a simulated environment. It involves the coordination of scope tip steering with scope insertion, using a rotated image as reference. The purpose of this work is to develop and validate a system which objectively assesses colonoscopy technical skills proficiency in an arbitrary training environment, allowing novices to assess their technical proficiency prior to real patient encounters.

Methods

We implemented a motion tracking setup to objectively analyze and assess the way operators perform colonoscopies, including an analysis of wrist and elbow joint motions. Subsequently, we conducted a validation study to verify whether our motion analysis could discriminate novice colonoscopists from experts. Participants navigated a wooden bench-top model using a standard colonoscope while their motions were tracked.

Results

The developed motion tracking setup allowed colonoscopists of varying levels of proficiency to have their colonoscope manipulation assessed, and was able to be operated by a trained non-technical operator. Novice operators had significantly greater median times (101.5 vs. 31.5 s) and number of hand movements (62.0 vs. 21.5) than experts. Experts, however, spent a significantly greater proportion of time in extreme ranges of wrist and elbow joint motion than novices.

Conclusion

We have developed and implemented a hand and joint motion analysis system that is able to discriminate novices from experts based on objective measures of motion. These metrics could, thus, serve as proxies for technical proficiency during training.

http://ift.tt/2A2OFq7

Association of the GRIN2B Gene Polymorphism with Verbal Fluency and Impairments to Abstract Thought in Schizophrenia

Objective. This study was conducted to seek associations between the GRIN2B gene and signs of impairments to thought and speech in schizophrenia, which may be based on access to the mental lexicon. Materials and methods. A group 552 patients with schizophrenia spectrum disorders were studied to establish associations between the rs7301328 polymorphism of the GRIN2B gene and semantic verbal fluency and five symptoms of impairments to thought and speech on the Positive and Negative Syndrome Scale (PANSS). Results and conclusions. Associations between the GRIN2B gene and verbal fluency (p = 0.013) and impairment to abstract thought (p = 0.012) were found. Verbal fluency was not found to have a mediatory role in the association between the gene and the impairment to thought. These results suggest that the GRIN2B gene has a modifying action on language processes extracting information from the mental lexicon on the basis of semantic features and, furthermore, that it makes a contribution to the variability of clinically marked impairments to abstract thought in patients with schizophrenia. The heterozygous genotype may be protective in relation to the development of thought and speech pathology.

http://ift.tt/2zRJ3OF

Long-Term Effects of Stressors during the Neonatal Period of Development on the Nociceptive System and Psychoemotional Behavior

The long-term effects of peripheral inflammatory pain, transient maternal separation stress, and the combination of these factors on days 1 and 2 of life or on days 7 and 8 of life were studied in relation to measures of baseline pain (in the absence of an inflammatory process), prolonged responses to reinitiation of inflammation in the formalin test, levels of anxiety, extents of depressive behavior, and spatial learning ability when the animals reached adult age (90 days). In adult rats, study parameters showed changes depending on the type of early treatment and the age at which it was applied: inflammatory pain induced hypoalgesia in the hotplate test and degraded spatial learning ability in the Morris maze; maternal separation stress on days 1–2 but not days 7–8 increased pain responses in the formalin test. Regardless of the age at which the rat pups were subjected to treatments, repeated induction of inflammatory foci induced increased pain responses when animals reached adulthood. In the forced swimming test, immobility was increased in rats subjected to any of the treatments. The effects of combined pain and stress did not increase the influences of each applied alone. These new data contribute to the further development of our understanding of the longterm influences of harmful pain and stressors and their interactions in the neonatal period of development on the functional activity of the tonic nociception system and psychoemotional behavior.

http://ift.tt/2hn4Uqr

Morphological Changes and Characteristics of the Expression of Serine Racemase in the Rat Hippocampus in Combined Stress

Structural changes in the ventral segment of the hippocampus and the characteristics of the expression of serine racemase were studied in rats aged 12 and 24 months exposed to combined stress. Four groups of 10 animals were formed: group 1 were control rats aged 12 months; group 2 were control rats aged 24 months; group 3 were 12-month rats subjected to 30-min stress daily for seven days; group 4 were 24-month rats subjected to stress. Stress was applied in a special apparatus consisting of six isolated sectors of identical volume and allowing the combination of different types of stress to be applied (pulsing light, loud noise, vibration). The ventral segment of the hippocampus of experimental animals showed an increase in the specific number of shrunken hyperchromic neurons in field CA3 and decreases in neuron density, accompanied by pericellular edema, cytoplasmic vacuolization, and decreased serine racemase expression in the neuropil of the radial layer of fields CA1 and CA3. Stressed animals showed changes in neurons in the pyramidal layer of field CA3, which were combined with a decrease in the level of expression of serine racemase in dendrites in the radial layer of fields CA1 and CA3, which is taken as a sign of impairment to NMDA receptor-mediated transmission of nerve spikes in the hippocampus.

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Individual Features of Viewing Emotionally Significant Images

Experimental data on the individual features of eye movements on viewing affective images from the IAPS database are presented. The results provide evidence that the viewing trajectory in each subject (n = 20) persisted on presentation of images with different emotional coloration. The whole cohort of subjects showed a significant correlation between the numbers of tests in which areas of interest were detected, in three combinations: between negative and positive images, between negative and neutral, and between positive and neutral (r = 0.84, 0.78, and 0.77, respectively). Analogous correlations were seen for the duration of gaze fixations (r = 0.90, 0.82, and 0.90). The number of fixation points in areas of interest, the size of the areas examined, and the duration of fixations were found to differ significantly between two groups of subjects (with dominance of focal or scanning gaze trajectories). The potential for using emotionally significant images for assessing the dominant type of visual attention in terms of eye movement parameters in individual humans is discussed.

http://ift.tt/2zQ2IP6