Modal analysis in 2D media with variable disorder

Modal properties of 2D disordered optical structures have been numerically analyzed, in the Mid-IR region, varying the amount of scattering and the disorder level. The modal properties study has been carried out through the use of Finite Element Method, highlighting the localized regime transition and investigating the quality factor. The results have been interpreted in a statistical fashion, investigating light diffusion in these structures with the help of Monte Carlo Method. An alternative measure of randomness weight has been proposed to support the numerical results.

Activation of autophagy in rats with plateau stress-induced intestinal failure

Hypobaric hypoxia may damage the intestinal mucosa, which may induce multiple organ dysfunction. However, little work has been done regarding whether high altitude hypoxia is associated with failure of the intestinal mucosal barrier. The aim of this study was to investigate the change of the autophagy after the intestinal failure in rats acutely exposed to plateau stress. Fifty Wistar rats were randomly divided into five groups: the plain group, plateau for 6 h, 12 h, 24 h, and 48 h (n = 10 in each group). The acute exposure to plateau was established at a simulated altitude of 4767 meters (m) in a decompression chamber. Intestinal injury was verified by light microscopy. The autophagosomes in the intestinal epithelial cells were observed by transmission electron microscopy (TEM). The protein expression of Beclin1 and LC3B in the intestinal epithelial cells were analyzed by immunohistochemistry. Compared with the plain group, acute exposure to plateau led to a time-dependent damage of the intestinal epithelium. The autophagosome was observed after the intestinal failure following acute exposure to high altitude for 6 h. The expression of Beclin1 and LC3B protein in the rats exposed to acute plateau for 6 h, 12 h, 24 h and 48 h were significantly higher than those in the plain group. The expression of autophagy also showed a significant increase in rats with intestinal failure following acute exposure to plateau stress.

Immune response of γδT cells in Schistosome japonicum-infected C57BL/6 mouse liver

Systematic evaluation of the role of γδT cells during the Schistosoma japonicum infection has not been reported, despite the fact that γδT cells contribute to many infectious diseases in innate immunity. Therefore, the aim of this study was to observe the properties of γδT cells in the liver of C57BL/6 mice infected by S. japonicum. In this report, using immuno-fluorescent histological analysis, γδT cells were found around hepatic granulomatous. Moreover, the flow cytometry results revealed that the percentage of hepatic γδT cells increased significantly after S. japonicum infection. More interestingly, a subset of CD3(-)γδTCR(+) cells were found and markedly increased after infection. Furthermore, expression of activation markers (CD25 and CD69) and cytokine profiles were detected in these hepatic CD3(+)γδTCR(+) and CD3(-)γδTCR(+) cells. The significantly higher level of CD69, IL-4 and IL-17 were observed in CD3(+)γδTCR(+) cells after infection, suggesting that CD3(+)γδTCR(+) cells instead of CD3(-)γδTCR(+) cells might play a predominant role during the infection. Finally, our results indicated that the expression of NKG2D on CD3(+)γδTCR(+) cells was higher than that on CD3(-)γδTCR(+) cells. Collectively, γδT cells could play an important role in the liver of C57BL/6 mouse during japonicum infection.

Structural plasticity of helical nanotubes based on coiled-coil assemblies

Numerous instances can be seen in evolution in which protein quaternary structures have diverged while the sequences of the building blocks have remained fairly conserved. However, the path through which such divergence has taken place is usually not known. We have designed two synthetic 29-residue α-helical peptides, based on the coiled-coil structural motif, that spontaneously self-assemble into helical nanotubes in vitro. Using electron cryomicroscopy with a newly available direct electron detection capability, we can achieve near-atomic resolution of these thin structures. We show how conservative changes of only one or two amino acids result in dramatic changes in quaternary structure, in which the assemblies can be switched between two very different forms. This system provides a framework for understanding how small sequence changes in evolution can translate into very large changes in supramolecular structure, a phenomenon that may have significant implications for the de novo design of synthetic peptide assemblies.

Oxytocin-induced membrane hyperpolarization in pain-sensitive dorsal root ganglia neurons mediated by Ca(2+)/nNOS/NO/KATP pathway

Oxytocin (OT) plays an important role in pain modulation and antinociception in the central nervous system. However, little is known about its peripheral effects. This study was conducted to investigate the effect of OT on the electrical properties of neurons in the dorsal root ganglia (DRG) and the underlying mechanisms. DRG neurons from adult rats were acutely dissociated and cultured. Intracellular Ca(2+) was determined by fluorescent microscopy using an indicator dye. The electrical properties of DRG neurons were tested by patch-clamp recording. The oxytocin receptor (OTR) and neuronal nitric oxide synthase (nNOS) on DRG neurons were assessed with immunofluorescence assays. OTR co-localized with nNOS in most of Isolectin B4 (IB4)-binding cultured DRG neurons in rats. OT decreased the excitability, increased the outward current, and evoked the membrane hyperpolarization in cultured DRG neurons. Sodium nitroprusside (SNP), the donor of nitric oxide (NO), exerted similar effects as OT on the membrane potential of cultured DRG neurons. OT increased the production of NO in DRGs and cultured DRG neurons. Pre-treatment of the OTR antagonist atosiban or the selective nNOS inhibitor N-Propyl-l-arginine (NPLA) significantly attenuated the hyperpolarization effect evoked by OT. OT produced a concentration-dependent increase in intracellular Ca(2+) in DRG neurons that responds to capsaicin, which can be attenuated by atosiban, but not by NPLA. OT-evoked membrane hyperpolarization and increase of outward current were distinctly attenuated by glibenclamide, a blocker of ATP-sensitive K(+) (KATP) channel. OT might be an endogenous antinociceptive agent and the peripheral antinociceptive effects of OT are mediated by activation of the Ca(2+)/nNOS/NO/KATP pathway in DRG neurons.

Comparison of the effects on glycaemic control and β-cell function in newly diagnosed type 2 diabetes patients of treatment with exenatide, insulin or pioglitazone: a multicentre randomized parallel-group trial (the CONFIDENCE study)

OBJECTIVE

Progressive β-cell dysfunction hinders the maintenance of glycaemic control in type 2 diabetes, but comparative data on β-cell-protective therapies are lacking in the early stage of type 2 diabetes. Here we evaluated the comparative glycaemic efficacy and impact on β-cell function of three antihyperglycaemic agents that have a β-cell-protective effect, exenatide, insulin and pioglitazone, in newly diagnosed patients with type 2 diabetes.

DESIGN AND METHODS

In this 48-week, multicentre, parallel-group study, 416 patients newly diagnosed with type 2 diabetes were randomly assigned 1 : 1 : 1 to receive exenatide, insulin or pioglitazone. The primary end-point was the change in glycosylated haemoglobin (HbA1c) from baseline. Secondary end-points included effects on weight, blood pressure, lipid profiles and β-cell function assessed by homeostasis model assessment, fasting proinsulin:insulin (PI/I), disposition index (DI) and acute insulin response (AIR).

RESULTS

At week 48, mean [95% confidence interval (CI)] HbA1c changes from baseline were -1.8% (-1.55% to -2.05%) with exenatide, -1.7% (-1.52% to -1.96%) with insulin and -1.5% (-1.23% to -1.71%) with pioglitazone. Treatment differences were -0.20% (95% CI -0.46% to 0.06%) for exenatide versus insulin (P = 0.185), and -0.37% (95% CI -0.63% to -0.12%) for exenatide versus pioglitazone (P = 0.002). Significant improvements from baseline in AIR, PI/I and DI were observed with all treatments, with the greatest improvements in DI, as well as weight, blood pressure and lipid profile, observed with exenatide.

CONCLUSIONS

All three agents showed efficacy regarding glycaemic control and metabolic benefits; however, exenatide showed the greatest efficacy. β-cell function improved in all treatment groups; hence, early initiation of β-cell-protective therapy may halt the decline in β-cell function in type 2 diabetes.

A novel non-enzymatic amperometric glucose sensor based on a hollow Pt–Ni alloy nanotube array electrode with enhanced sensitivity

A non-enzymatic electrode is proposed as a glucose sensor based on Pt-replaced Ni nanowires which are prepared by constant current electro-deposition within the anodic alumina membrane and galvanic replacement reaction.

Nontraditional risk factors for cardiovascular disease and visceral adiposity index among different body size phenotypes

BACKGROUND AND AIMS

Increased cardiovascular disease and mortality risk in metabolically healthy obese (MHO) individuals remain highly controversial. Several studies suggested risk while others do not. The traditional cardiovascular risk factors may be insufficient to demonstrate the complete range of metabolic abnormalities in MHO individuals. Hence, we aimed to compare the prevalence of elevated lipoprotein (a), apolipoprotein B, and uric acid (UA) levels, apolipoprotein B/apolipoprotein A1 ratio, and visceral adiposity index (VAI) scores, and low apolipoprotein A1 levels among 6 body size phenotypes (normal weight with and without metabolic abnormalities, overweight with and without metabolic abnormalities, and obese with or without metabolic abnormalities).

METHODS AND RESULTS

We conducted a cross-sectional analysis of 7765 Chinese adults using data from the nationwide China Health and Nutrition Survey 2009. MHO persons had intermediate prevalence of elevated apolipoprotein B and UA levels, apolipoprotein B/apolipoprotein A1 ratio and VAI scores, and low apolipoprotein A1 levels between metabolically healthy normal-weight (MHNW) and metabolically abnormal obese individuals (P < 0.001 for all comparisons). Elevated apolipoprotein B and UA concentrations, apolipoprotein B/apolipoprotein A1 ratio, and VAI scores were all strongly associated with the MHO phenotype (all P < 0.01).

CONCLUSIONS

Prevalence of elevated apolipoprotein B and UA levels, apolipoprotein B/apolipoprotein A1 ratio and VAI scores, and low levels of apolipoprotein A1 was higher among MHO persons than among MHNW individuals. The elevated levels of the nontraditional risk factors and VAI scores in MHO persons could contribute to the increased cardiovascular disease risk observed in long-term studies.

Synthesis of Sn–Co@PMMA nanowire arrays by electrodeposition and in situ polymerization as a high performance lithium-ion battery anode

Transition metals have attracted much attention due to their high energy density in lithium-ion batteries (LIBs).

Upregulated sirtuin 1 by miRNA-34a is required for smooth muscle cell differentiation from pluripotent stem cells

microRNA-34a (miR-34a) and sirtuin 1 (SirT1) have been extensively studied in tumour biology and longevity/aging, but little is known about their functional roles in smooth muscle cell (SMC) differentiation from pluripotent stem cells. Using well-established SMC differentiation models, we have demonstrated that miR-34a has an important role in SMC differentiation from murine and human embryonic stem cells. Surprisingly, deacetylase sirtuin 1 (SirT1), one of the top predicted targets, was positively regulated by miR-34a during SMC differentiation. Mechanistically, we demonstrated that miR-34a promoted differentiating stem cells' arrest at G0/G1 phase and observed a significantly decreased incorporation of miR-34a and SirT1 RNA into Ago2-RISC complex upon SMC differentiation. Importantly, we have identified SirT1 as a transcriptional activator in the regulation of SMC gene programme. Finally, our data showed that SirT1 modulated the enrichment of H3K9 tri-methylation around the SMC gene-promoter regions. Taken together, our data reveal a specific regulatory pathway that miR-34a positively regulates its target gene SirT1 in a cellular context-dependent and sequence-specific manner and suggest a functional role for this pathway in SMC differentiation from stem cells in vitro and in vivo.

The Chinese First-Episode Schizophrenia Trial: background and study design

Schizophrenia is a complex illness with unknown aetiology and pathogenesis. Currently, a considerable number of patients with schizophrenia do not receive standardised and systematic treatment in China. In the past years, many controlled trials have been conducted in chronic schizophrenia. In contrast, research on first-episode schizophrenia is lacking. This paper describes the background and design of the Chinese First-Episode Schizophrenia Trial project--a multicentre, randomised, open-label clinical trial. A total of 600 first-episode schizophrenia patients were randomly divided into 3 groups and treated with risperidone, aripiprazole, and olanzapine for 1 year. During the study period, only 1 medication change of the 3 antipsychotic medications was allowed.

The accuracy of ultrasonography and magnetic resonance imaging for the diagnosis of Morton's neuroma: a systematic review

AIM

To determine the accuracy of MRI versus ultrasound for Morton's neuroma.

MATERIALS AND METHODS

A search was undertaken for clinical studies published in any language in PubMed up to the date of December 2013. Studies assessing the accuracy of the ultrasound or MRI for the diagnosis of Morton's neuroma were included. Data were pooled for meta-analysis. Study selection, data collection, and extraction were performed independently by two authors. Meta-disc 1.4 and Revman 5.2 software were applied for statistical analysis.

RESULTS

The study included 12 studies; 217 patients underwent MRI and 241 underwent ultrasound examinations. There appeared greater diagnostic accuracy for ultrasound than MRI for the diagnosis of Morton's neuroma (ultrasound sensitivity 90%, specificity 88%, positive likelihood ratio 2.77, negative likelihood ratio 0.16 versus MRI sensitivity 93%, specificity 68%, positive likelihood ratio 1.89, negative likelihood ratio 0.19).

CONCLUSIONS

The available evidence suggests that ultrasound can provide better accuracy for the diagnosis of Morton's neuroma than MRI.

miR-1247 is correlated with prognosis of pancreatic cancer and inhibits cell proliferation by targeting neuropilins

Accumulating evidence indicates that microRNAs (miRNAs) have great potential as tumor biomarkers and therapeutic agents owing to their functions in tumorigenesis and cancer progression. Aberrant expression of miR-1247 has been found in several cancers and is predicted to play an important role in the pathological processes of pancreatic cancer by miRNA-regulated network analysis. We investigated the expression profile of miR-1247 in pancreatic cancer tissue microarray by in situ hybridization and found that miR-1247 was significantly down-regulated in pancreatic cancer tissues compared to matched benign tissues. High levels of miR-1247 expression were positively correlated with higher overall and recurrence free survival in pancreatic cancer patients, while negatively correlated with tumor grade. Using in vitro and in vivo models, we demonstrated that increased expression of miR-1247 inhibited proliferation, tumorigenicity, colony formation and triggered G0/G1 cell cycle arrest in pancreatic cancer cells. Moreover, we confirmed that neuropilin1 (NRP1) and neuropilin2 (NRP2) are direct targets of miR-1247 by western blot and luciferase reporter assay. Further studies indicated that low dose all trans retinoic acid (ATRA) can induce redifferentiation and restoration of miR-1247 in pancreatic cancer cells. These findings suggest that miR-1247, a novel tumor suppressor, can act as a potential biomarker and therapeutic agent for pancreatic cancer.

Influence of base-region thickness on the performance of Pnp transistor-VCSEL

We have recently reported a 980nm GaAs-based three terminal Pnp transistor-vertical-cavity surface-emitting laser (TVCSEL) operating at room temperature with optical power up to 1.8mW. However, the current gain β = ΔIc/ΔIb was near zero just before lasing and became negative after the lasing threshold. The main cause of the negative current gain was found to be a gradual and position-dependent forward-biasing (saturation) of the base-collector junction with increasing bias even before lasing threshold. In this article, detailed multi-physics device simulations are performed to better understand the device physics, and find ways to avoid the premature saturation of the base-collector junction. We have optimized the thickness of the base region as well as its doping concentration and the location of the quantum wells to ensure that the T-VCSEL is in the active mode throughout its range of operation. That is, the emitter-base junction is forward biased and base-collector junction is reversed biased for sweeping the excess charges out of the base region.