Cold-nuclear-matter effects on heavy-quark production at forward and backward rapidity in d + Au collisions at √sNN = 200 GeV

The PHENIX experiment has measured open heavy-flavor production via semileptonic decay over the transverse momentum range 1 < p(T) < 6  GeV/c at forward and backward rapidity (1.4 < |y| < 2.0) in d+Au and p + p collisions at √sNN = 200  GeV. In central d+Au collisions, relative to the yield in p + p collisions scaled by the number of binary nucleon-nucleon collisions, a suppression is observed at forward rapidity (in the d-going direction) and an enhancement at backward rapidity (in the Au-going direction). Predictions using nuclear-modified-parton-distribution functions, even with additional nuclear-p(T) broadening, cannot simultaneously reproduce the data at both rapidity ranges, which implies that these models are incomplete and suggests the possible importance of final-state interactions in the asymmetric d + Au collision system. These results can be used to probe cold-nuclear-matter effects, which may significantly affect heavy-quark production, in addition to helping constrain the magnitude of charmonia-breakup effects in nuclear matter.

A polymorphism in melanoma differentiation-associated gene 5 may be a risk factor for enterovirus 71 infection

Enterovirus 71 (EV71) infection has a wide variety of clinical manifestations, from no symptoms to fatal disease. Host immune response may be a determinant of disease severity. We investigated the association of polymorphisms in three pattern recognition receptor (PRR) genes-toll-like receptor 3 (TLR3) (rs3775291), retinoic acid-inducible gene I (RIG-I) (rs10813831) and melanoma differentiation-associated gene 5 (MDA5) (rs1990760)-with the severity of EV71 infection. Polymorphisms of candidate genes in 87 EV71-infected patients and 57 asymptomatic controls were detected. Binary logistic regression analysis revealed statistically significant differences in polymorphism of MDA5 (rs1990760) between patients with severe EV71 infection and asymptomatic controls in an additive model (OR 0.424, 95% CI 0.213-0.845, p 0.015) and a dominant model (OR 0.256, 95% CI 0.103-0.635, p 0.003). Polymorphism of MDA5 (rs1990760) (OR 0.399, 95% CI 0.199-0.798, p 0.009) was found to be associated with the severity of EV71 infection with the analysis of ordinal logistic regression. These results indicated the association between MDA5 (rs1990760) polymorphism and an increased risk of a severe EV71 infection in Chinese children, which offers potential for investigating the innate immune mechanism of EV71 infection and identifying at-risk infants, for whom a preventive strategy may reduce the severity of EV71 infection.

Effects of common polymorphisms rs2910164 in miR-146a and rs11614913 in miR-196a2 on susceptibility to colorectal cancer: a systematic review meta-analysis

PURPOSE

Emerging evidence has shown that single nucleotide polymorphisms occurred in microRNAs may contribute to the development of colorectal cancer (CRC). rs2910164 in miR-146a and rs11614913 in miR-196a2 are suggested to be associated with the susceptibility to CRC, but individually published studies revealed inconclusive results. To systematically summarize the possible correlationship between these polymorphisms and CRC risk, we performed this meta-analysis.

METHODS

We retrieved the relevant articles of the associations between these two microRNA polymorphisms and susceptibility to CRC for the period up to July 1, 2013. A total of seven articles were identified with 2,143 cases and 2,457 controls for miR-146a rs2910164, 1,594 cases and 2,252 controls for miR-196a2 rs11614913. Odds ratio and 95 % confidence interval were calculated to investigate the strength of the association.

RESULTS

The pooled analysis showed that miR-146a rs2910164 did not reveal any correlation with CRC susceptibility. However, a decreased risk was observed between miR-196a2 rs11614913 and CRC in all genetic models.

CONCLUSION

Our current meta-analysis demonstrates that miR-196a2 rs11614913 most likely contributes to decreased risk of CRC, whereas miR-146a rs2910164 may not be associated with the susceptibility to CRC.

Ang(1-7) treatment attenuates β-cell dysfunction by improving pancreatic microcirculation in a rat model of Type 2 diabetes

AIMS

Pancreatic microcirculation plays a pivotal role in the physiological function and survival of β-cells. Ang(1- 7) is a novel component of the renin angiotensin system (RAS) that has beneficial effects on microcirculation. In the present study, we investigated the effects of systemic Ang(1-7) administration (with or without its receptor Mas antagonist A- 779) on pancreatic microcirculation and β-cell function.

METHODS

These effects were studied in vivo using a rat model of Type 2 diabetes (T2DM). Pancreatic microcirculation and islet microvessel density were measured; and β-cell function, insulin content, and the apoptosis of islet cells were assessed, respectively. Additionally, we evaluated endothelial nitric oxide synthase (eNOS) expression and nitric oxide (NO) concentration in islets.

RESULTS

After Ang(1-7) intervention, pancreatic microcirculation and intra-islet microvessel density were significantly improved (p<0.05), and more importantly, first-phase insulin secretion of β-cells as well as relative insulin content in islets were increased, and the amount of apoptotic islet cells was decreased (p<0.05). And eNOS expression and NO release were up-regulated in pancreatic islets by Ang(1-7) administration (p<0.05). These positive effects of Ang(1-7) were prevented by the addition of A-779 (p<0.05).

CONCLUSIONS

Our findings suggest that systemic Ang(1-7) treatment could attenuate β-cell dysfunction and ameliorate islet cell apoptosis in T2DM rats by improving pancreatic microcirculation, perhaps through the mechanism of endothelial vasodilation.

Strong field multiple ionization as a route to electron dynamics in a van der Waals cluster

We study the order in which a strong laser field removes multiple electrons from a van der Waals (vdW) cluster. The N2Ar, with an equilibrium T-shaped geometry, contains both a covalent and a vdW bond and serves as a simple yet rich example. Interestingly, the fragmenting double and triple ionizations of N2Ar with vdW bond breaking are favored when the vdW bond is aligned along the laser field polarization vector. However, the orientation of the covalent bond with respect to the laser field rules the triple ionization when both the covalent and vdW bonds are simultaneously broken. Electron-localization-assisted enhanced ionization and molecular orbital profile-dominated, orientation-dependent ionization are discussed to reveal the order of electrons release from different sites of N2Ar.

Medium modification of jet fragmentation in Au+Au collisions at √[s(NN)]=200 GeV measured in direct photon-hadron correlations

The jet fragmentation function is measured with direct photon-hadron correlations in p+p and Au+Au collisions at √[s(NN)]=200 GeV. The p(T) of the photon is an excellent approximation to the initial p(T) of the jet and the ratio z(T)=p(T)(h)/p(T)(γ) is used as a proxy for the jet fragmentation function. A statistical subtraction is used to extract the direct photon-hadron yields in Au+Au collisions while a photon isolation cut is applied in p+p. I(AA), the ratio of hadron yield opposite the photon in Au+Au to that in p+p, indicates modification of the jet fragmentation function. Suppression, most likely due to energy loss in the medium, is seen at high z(T). The associated hadron yield at low z(T) is enhanced at large angles. Such a trend is expected from redistribution of the lost energy into increased production of low-momentum particles.

2D divertor heat flux distribution using a 3D heat conduction solver in National Spherical Torus Experiment

The divertor heat flux footprint in tokamaks is often observed to be non-axisymmetric due to intrinsic error fields, applied 3D magnetic fields or during transients such as edge localized modes. Typically, only 1D radial heat flux profiles are analyzed; however, analysis of the full 2D divertor measurements provides opportunities to study the asymmetric nature of the deposited heat flux. To accomplish this an improved 3D Fourier analysis method has been successfully applied in a heat conduction solver (TACO) to determine the 2D heat flux distribution at the lower divertor surface in the National Spherical Torus Experiment (NSTX) tokamak. This advance enables study of helical heat deposition onto the divertor. In order to account for heat transmission through poorly adhered surface layers on the divertor plate, a heat transmission coefficient, defined as the surface layer thermal conductivity divided by the thickness of the layer, was introduced to the solution of heat conduction equation. This coefficient is denoted as α and a range of values were tested in the model to ensure a reliable heat flux calculation until a specific value of α led to the constant total deposited energy in the numerical solution after the end of discharge. A comparison between 1D heat flux profiles from TACO and from a 2D heat flux calculation code, THEODOR, shows good agreement. Advantages of 2D heat flux distribution over the conventional 1D heat flux profile are also discussed, and examples of 2D data analysis in the study of striated heat deposition pattern as well as the toroidal degree of asymmetry of peak heat flux and heat flux width are demonstrated.

Associations between coronary heart disease and individual components of the metabolic syndrome according to glucose tolerance status

OBJECTIVE

To assess whether the contributions of individual metabolic syndrome components to coronary heart disease (CHD) risk vary in patients with different glucose tolerance.

METHODS

A total of 1619 patients were included in this cross-sectional study. CHD, metabolic syndrome and glucose tolerance were assessed using coronary angiography, anthropometric and biochemical parameters, and an oral glucose tolerance test, respectively. Associations between CHD and components of metabolic syndrome were determined using logistic regression analysis.

RESULTS

Low high-density lipoprotein-cholesterol (HDL-C) was the only CHD risk factor in patients with both CHD and metabolic syndrome who had normal glucose tolerance, after adjustments for age, smoking and low-density lipoprotein-cholesterol (LDL-C) concentration. In patients with CHD plus metabolic syndrome and prediabetes, the most important risk factor was hypertension; additional risk factors were high postprandial blood glucose (PBG) and low HDL-C. In patients with CHD plus metabolic syndrome and diabetes, high PBG was the strongest risk factor, followed by hypertension, high FBG and high waist circumference.

CONCLUSIONS

Individual components of metabolic syndrome contributed variously to CHD across different glucose tolerance statuses.

Anorectal function after partial intersphincteric resection in ultra-low rectal cancer

AIM

To investigate the feasibility and efficacy of intersphincteric resection (ISR), in terms of postoperative anorectal function, for ultra-low rectal cancer in mainland China.

METHOD

A total of 43 patients who consecutively underwent curative partial ISR for ultra-low rectal cancer between 2006 and 2009 were enrolled in the study. Defaecatory function was assessed, using detailed questionnaires, 3, 6 and 12 months after surgery. The Wexner score was used to assess faecal continence, and anal manometry studies were performed to analyse anal sphincter function.

RESULTS

Overall defaecatory function was assessed as being satisfactory in 41 of 43 patients. Twelve months after surgery, the mean Wexner score was 4.0 ± 3.6. Anal manometry studies showed a significant change at 3 months and further, gradual, improvement over the following year. During the postoperative period, maximum squeeze pressure reached a normal value of 174.1 ± 19.5 mmHg (P = 0.041) by 6 months and resting pressure was 42.4 ± 5.6 mmHg by 12 months, which was close to the preoperative level (P = 0.038).

CONCLUSION

Because of the satisfactory recovery of defaecatory function and good oncological results, partial ISR may be recommended as an effective sphincter-preserving operation for patients with ultra-low rectal cancer.

Evolution of π(0) suppression in Au+Au collisions from √(s(NN))=39 to 200 GeV

Neutral-pion π(0) spectra were measured at midrapidity (|y|<0.35) in Au+Au collisions at √(s(NN))=39 and 62.4 GeV and compared with earlier measurements at 200 GeV in a transverse-momentum range of 1<p(T)<10 GeV/c. The high-p(T) tail is well described by a power law in all cases, and the powers decrease significantly with decreasing center-of-mass energy. The change of powers is very similar to that observed in the corresponding spectra for p+p collisions. The nuclear modification factors (R(AA)) show significant suppression, with a distinct energy, centrality, and p(T) dependence. Above p(T)=7 GeV/c, R(AA) is similar for √(s(NN))=62.4 and 200 GeV at all centralities. Perturbative-quantum-chromodynamics calculations that describe R(AA) well at 200 GeV fail to describe the 39 GeV data, raising the possibility that, for the same p(T) region, the relative importance of initial-state effects and soft processes increases at lower energies. The p(T) range where π(0) spectra in central Au+Au collisions have the same power as in p+p collisions is ≈5 and 7 GeV/c for √(s(NN))=200 and 62.4 GeV, respectively. For the √(s(NN))=39 GeV data, it is not clear whether such a region is reached, and the x(T) dependence of the x(T)-scaling power-law exponent is very different from that observed in the √(s(NN))=62 and 200 GeV data, providing further evidence that initial-state effects and soft processes mask the in-medium suppression of hard-scattered partons to higher p(T) as the collision energy decreases.

Polydatin Protects against Lipopolysaccharide-Induced Fulminant Hepatic Failure in D-Galactosamine-Sensitized Mice

Fulminant hepatic failure (FHF) is a devastating clinical syndrome with extremely poor prognosis and high mortality. Therefore, better treatment is urgently needed. Polydatin (PD), a traditional anti-inflammatory drug, has been described to protect against liver injury induced by certain hepatotoxins. The present study investigated the protective effect of PD against lipopolysaccharide (LPS)/D-galactosamine (D-GalN)-induced FHF in mice and the underlying mechanism. Mice were pretreated with an increasing dose of PD (10, 30, and 100 mg/kg), following LPS/D-GalN challenge. The liver injury was assessed biochemically and histologically. We found that PD exerted a protective effect on LPS/D-GalN-induced FHF as evidenced by reducing sera alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, diminishing liver histopathological injury, and lowering mortality in a dose-dependent manner. In addition, pretreatment mice with PD dose-dependently suppressed tumor necrosis factor-α (TNF-α) production, myeloperoxidase (MPO) activity, intercellular adhesion molecule-1 (ICAM-1) and endothelial cell adhesion molecule-1 (ECAM-1) expression, caspase-3 activation, and transcription factor nuclear factor-kappa B(NF-kB) activity induced by LPS. These results suggested that PD could effectively protect from LPS/D-GalN-induced FHF and the protective effect afforded by PD probably contributed to reduce TNF-α production via inhibiting NF-kB activation.

Biochemical analysis of a highly specific, pH stable xylanase gene identified from a bovine rumen-derived metagenomic library

A metagenomic library was generated using microbial DNA extracted from the rumen contents of a grass hay-fed dairy cow using a bacterial artificial chromosome-based vector system. Functional screening of the library identified a gene encoding a potent glycoside hydrolase, xyn10N18, localised within a xylanolytic gene cluster consisting of four open-reading frames (ORFs). The ORF, xyn10N18, encodes an endo-β-1,4-xylanase with a glycosyl hydrolase family 10 (GH10) catalytic domain, adopts a canonical α8/ß8-fold and possesses conserved catalytic glutamate residues typical of GH10 xylanases. Xyn10N18 exhibits optimal catalytic activity at 35 °C and pH 6.5 and was highly stable to pH changes retaining at least 85 % relative catalytic activity over a broad pH range (4.0-12.0). It retained 25 % of its relative activity at both low (4 °C) and high (55 °C) temperatures, however the stability of the enzyme rapidly decreased at temperatures of >40 °C. The specific activity of Xyn10N18 is enhanced by the divalent cations Mn(2+) and Co(2+) and is dramatically reduced by Hg(2+) and Cu(2+). Interestingly, EDTA had little effect on specific activity indicating that divalent cations do not function mechanistically. The enzyme was highly specific for xylan containing substrates and showed no catalytic activity against cellulose. Analysis of the hydrolysis products indicated that Xyn10N18 was an endoxylanase. Through a combination of structural modelling and in vitro enzyme characterisation this study provides an understanding of the mechanism and the substrate specificity of this enzyme serving as a starting point for directed evolution of Xyn10N18 and subsequent downstream use in industry.

Intramural delivery of bortezomib inhibits restenosis following arterial injury

BACKGROUND

Several studies have demonstrated that the proteasome inhibitors prevent restenosis following arterial injury. The proteasome inhibitor bortezomib shows anti-inflammatory and antiproliferative effects. Here, we evaluate the efficacy of bortezomib in inhibiting the restenosis following arterial injury and the effect on nuclear factor kappa B (NF-kappaB) and p27.

METHODS

An injured iliac artery rabbit model was established by balloon over-stretching. Rabbits were intramurally infused with bortezomib or normal saline by a transport coronary dilatation catheter in the bortezomib (n = 20) or control (n = 20) groups, respectively, and they were sacrificed on the 7th or 21th day following the arterial injury. Neointimal area was measured by computer analysis of photomicrographs, while expression of NF-kappaB and of p27 on day 7 were evaluated by Western blotting and immunohistochemistry, respectively.

RESULTS

Expression of p27 (56.10 ± 3.03% vs. 10.24 ± 0.60%, p < 0.05) was significantly higher while that of NF-kappaB (0.44 ± 0.02 vs. 0.70 ± 0.03, p < 0.05) was significantly lower in the bortezomib group than in control group on day 7 after arterial injury. Neointimal formation was significantly lower in the bortezomib group on day 21 after arterial injury (0.67 ± 0.03 vs. 1.30 ± 0.05 intima/media ratio, p < 0.05).

CONCLUSIONS

Intramural delivery of bortezomib reduces neointimal formation, possibly via a mechanism involving upregulation of the p27 and downregulation of the NF-kappaB. Bortezomib therefore may be an alternative therapeutic approach for preventing restenosis.

Visualization of the internal cerebral veins on MR phase-sensitive imaging: comparison with 3D gadolinium-enhanced MR venography and fast-spoiled gradient recalled imaging

The purpose of this article is to compare the visualization quality of ICV and their tributaries on PSI-MRV, 3D CE-MRV, and 3D CE-FSPGR. PSI-MRV has been shown to delineate the ICV, TSV, SV, anterior caudate nucleus veins, and medial atrial veins effectively. Due to its advantages of no contrast material injection, acceptable examination times, and no arterial contamination, PSI-MRV should be considered in the evaluation of deep cerebral veins.

Implications of QRS duration in dogs with pacing-induced heart failure

The objective of this study was to find out the implication of QRS duration in dogs with rapid pacing-induced heart failure. Sixteen Beagle dogs were implanted with transvenous cardiac pacemakers and underwent rapid right ventricular pacing for 3 weeks at 260 bpm to induce heart failure. Dogs were divided into two groups according to the QRS duration: 9 with normal QRS duration (<100 ms) and 7 with prolonged QRS duration (≥100 ms). Cardiac systolic function and size was analyzed by real time 3-dimensional echocardiography and left ventricular dyssynchrony was assessed by speckle tracking strain imaging. Congestive heart failure developed 3 weeks after rapid right ventricular pacing. Dogs with prolonged QRS duration showed more extensive radial strain and circumferential strain dyssynchrony than dogs with normal QRS duration. At the end of 4-week recovery, greater improvement of left ventricular ejection fraction and left ventricular end-systolic volume was detected in dogs with normal QRS duration. The findings suggested that left ventricular dyssynchrony, indicated by a prolonged QRS duration, predicted an unsatisfying recovery in dogs with rapid pacing-induced heart failure. QRS duration had the potential to be a prognostic indicator for dogs with heart failure.