K/pi Fluctuations at relativistic energies

We report K/pi fluctuations from Au + Au collisions at sqrt[s(NN)]= 19.6, 62.4, 130, and 200 GeV using the STAR detector at the Relativistic Heavy Ion Collider. K/pi fluctuations in central collisions show little dependence on incident energy and are on the same order as those from NA49 at the Super Proton Synchrotron in central Pb + Pb collisions at sqrt[s(NN)]=12.3 and 17.3 GeV. We report results for the collision centrality dependence of K/pi fluctuations and results for charge-separated fluctuations. We observe that the K/pi fluctuations scale with the charged particle multiplicity density.

Characterizations of low-frequency zonal flow in the edge plasma of the HL-2A tokamak

A low-frequency (<4 kHz), poloidally and toroidally symmetrical potential structure that peaks near zero frequency is observed in the edge plasma of the HL-2A tokamak. The axisymmetry structure exhibits a radial coherence length less than 1 cm. These characteristics are consistent with the theoretically predicted low-frequency zonal flows (LFZF). The radial wave-number frequency spectra of the LFZF show that the LFZF packets propagate both outwards and inwards. The geodesic acoustic mode (GAM) is found to coexist with the LFZF, and the LFZF is found to modulate the GAM and ambient turbulence with in-phase and antiphase relations, respectively, through an envelope analysis.

Transient simulation of last deglaciation with a new mechanism for Bolling-Allerod warming

We conducted the first synchronously coupled atmosphere-ocean general circulation model simulation from the Last Glacial Maximum to the Bølling-Allerød (BA) warming. Our model reproduces several major features of the deglacial climate evolution, suggesting a good agreement in climate sensitivity between the model and observations. In particular, our model simulates the abrupt BA warming as a transient response of the Atlantic meridional overturning circulation (AMOC) to a sudden termination of freshwater discharge to the North Atlantic before the BA. In contrast to previous mechanisms that invoke AMOC multiple equilibrium and Southern Hemisphere climate forcing, we propose that the BA transition is caused by the superposition of climatic responses to the transient CO(2) forcing, the AMOC recovery from Heinrich Event 1, and an AMOC overshoot.

Clinicopathologic risk factors for distant metastases from head and neck squamous cell carcinomas

AIMS

The aim of this study is to investigate the clinicopathologic risk factors associated with distant metastases (DMs) from head and neck squamous cell carcinomas (HNSCCs).

METHODS

Between February 1990 and February 2000, a retrospective analysis of 391 HNSCC patients was performed. The frequency and the clinicopathologic risk factors for DM were evaluated by using univariate chi(2) tests and multiple stepwise logistic regression models. Statistical analysis of overall survival was performed by using Kaplan-Meier method.

RESULTS

44 patients (11.3%) developed DM in clinic. In a univariate analysis, clinical N stage, primary tumor site, level of tumor invasion, pathologic N stage and number of levels with pathologic lymph node were found to be significantly associated with the risk of DM. In a multivariate analysis, the most significant risk factors were number of levels with pathologic lymph node, level of tumor invasion, and primary tumor site. Kaplan-Meier analysis showed that overall survival rates of 44 patients with DMs in clinic were 56.8% at 1 year, 9.1% at 3 years, and 6.8% at 5 years, respectively.

CONCLUSIONS

The number of levels with pathologic lymph node, the site of primary tumor and the level of tumor invasion are decisive risk factors in determining the development of DM in head and neck SCC patients. Patients with multilevel nodal involvement in neck, with laryngeal and hypopharyngeal carcinomas, and patients with primary tumor invasion into muscular, bone or cartilage have the highest risk of developing DM.

ACEI/ARB therapy for IgA nephropathy: a meta analysis of randomised controlled trials

BACKGROUND

Published reports examining the efficacy of RAS blockers: angiotensin converting-enzyme inhibitor (ACEI) and angiotensin II receptor blocker (ARB) agents for preserving renal function in IgA nephropathy (IgAN) have yielded conflicting results. To evaluate systematically the effects of ACEI/ARB agents on IgAN, we conducted a meta analysis of published randomised controlled trials (RCTs).

METHODS

MEDLINE, EMBASE, the Cochrane Library and article reference lists were searched for RCTs that compared ACEI/ARB with placebo and any other antihypertensive agents or non-immunosuppressive agents for treating IgAN. The quality of the studies was evaluated with the method of intention to treat analysis and allocation concealment, as well as with the Jadad method. Meta analyses were performed on the outcomes of proteinuria and renal function in patients with IgAN.

RESULTS

Eleven RCTs involving 585 patients were included in the review. Seven trials used placebo/no treatment as controls. Four trials used other antihypertensive agents as controls. Overall, ACEI/ARB agents had statistically significant effects on protecting renal function(p < 0.00001) and reduction of proteinuria (p < 0.00001) when compared with control group. Tests for heterogeneity showed no difference in effect among the studies. Systolic and diastolic blood pressure, glomerular filtration rate (GFR), age, did not influence treatment response. ACEI/ARB agents were well tolerated.

CONCLUSIONS

The current cumulative evidence suggests that ACEI/ARB agents had statistically significant effects on protecting renal function and reduction of proteinuria in patients with IgAN when compared with control groups. ACEI/ ARB agents are a promising medication and should be investigated further.

HOGG1 polymorphism and gastric cancer/atrophic gastritis

e15535

Objective: 8-Hydroxydeoxyguanine (8-OHdG) formation is one of the most common types of oxidative DNA damage leading to gastric cancer development and human oxoguanine glycosylase 1(hOGG1) is responsible for repairing 8-OHdG lesions. Among several hOGG1 gene polymorphisms, the Ser→Cys polymorphism at position 326 is related to decreased repair function. We aimed to investigate the association between Ser326Cys hOGG1 polymorphism and gastric cancer/atrophic gastritis. Methods: 488 subjects (73 with gastric cancer, 160 with atrophic gastritis and 255 controls) were prospectively enrolled from 2005 to 2008 in Sir Run Run Shaw Hospital. Genomic DNA was obtained from peripheral blood and PCR-RFLP analysis was performed to distinguish the genotyping of hOGG1 Ser326Cys polymorphism. Statistical analysis was conducted by two-sample t-test or generalized regression models for continuous variables and the Pearson χ2 test for categorical variables. Logistic regression models were fitted to find the risk factors for gastric cancer and atrophic gastritis. For all analyses, significance was determined at the P < 0.05 level (two-tailed). Results: Patients with gastric cancer were significantly older than the control group (59.6±11.2yrs vs 43.6±10.3 yrs, P<0.0001) and atrophic gastritis group (59.6±11.2yrs vs 51.4±10.6 yrs, P<0.0001). Gastric cancer group had significantly higher rate of male than atrophic gastritis group (65.8% vs 48.7% in atrophic gastritis, p=0.02). Neither the hOGG1 Ser/Cys nor the Cys/Cys genotype was associated with gastric cancer, compared with the Ser/Ser genotype (OR: 0.96, 95% CI (0.51–1.84) and OR: 1.1, 95% CI: (0.48–2.1)). Ser/Cys and Cys/Cys were significantly associated with atrophic gastritis (OR: 1.76, 95% CI: 1.03–3.0) and OR: 2.38, 95%CI: 1.34–4.23)). After controlling for age, gender, smoking and alcohol, these significant associations still held with OR: 2.05, 95% CI: (1.14–3.68) for Ser/Cys and OR: 2.76, 95% CI: (1.47–5.18) for Cys/Cys. Conclusions: Our study supported that hOGG1 polymorphisms (genotype Ser/Cys and Cys/Cys) are associated with atrophic gastritis. These associations still exist after controlling for age, gender, smoking and alcohol. No significant association was detected between hOGG1 polymorphisms (genotype Cys/Cys or Ser/Cys) and gastric cancer.

No significant financial relationships to disclose.

Observation of two-source interference in the photoproduction reaction AuAu --> AuAurho0

In ultraperipheral relativistic heavy-ion collisions, a photon from the electromagnetic field of one nucleus can fluctuate to a quark-antiquark pair and scatter from the other nucleus, emerging as a rho{0}. The rho{0} production occurs in two well-separated (median impact parameters of 20 and 40 F for the cases considered here) nuclei, so the system forms a two-source interferometer. At low transverse momenta, the two amplitudes interfere destructively, suppressing rho{0} production. Since the rho{0} decays before the production amplitudes from the two sources can overlap, the two-pion system can only be described with an entangled nonlocal wave function, and is thus an example of the Einstein-Podolsky-Rosen paradox. We observe this suppression in 200 GeV per nucleon-pair gold-gold collisions. The interference is 87%+/-5%(stat.)+/-8%(syst.) of the expected level. This translates into a limit on decoherence due to wave function collapse or other factors of 23% at the 90% confidence level.

Indications of conical emission of charged hadrons at the BNL relativistic heavy ion collider

Three-particle azimuthal correlation measurements with a high transverse momentum trigger particle are reported for pp, d+Au, and Au+Au collisions at sqrt[s_{NN}]=200 GeV by the STAR experiment. Dijet structures are observed in pp, d+Au and peripheral Au+Au collisions. An additional structure is observed in central Au+Au data, signaling conical emission of correlated charged hadrons. The conical emission angle is found to be theta=1.37+/-0.02(stat)-0.07+0.06(syst), independent of p_{ perpendicular}.

Dual choice health insurance policy: a proposal and a cost analysis

The central issue in the current health care reform is cost. No health care reform can be successful without putting a rein on cost while maintaining a high quality of health care service. We believe one approach to solving the cost and quality issue is to allow patients the option to choose resources that are currently underutilized. Traditional health insurance plans offer consumers limited choice in that coverage is often denied when patients choose complementary and alternative medicine (CAM) treatments, even though the economic and social cost of treating certain conditions with alternative medicine may be more favorable than with conventional medicine. This article proposes a Dual Choice health insurance plan that would cover the cost of alternative medicines for certain medical conditions in the first stage. Should the alternative treatment turn out to be less effective, patients have the option to switch to conventional treatment in the second stage. Not only does this policy provide patients with more choices than in traditional plans, it will also likely provide significant cost savings while taking into account uncertainty regarding the effectiveness of CAM. By virtue of the wider choice offered to patients and lower cost, which is illustrated by a 2x2 effectiveness matrix, the authors think that insurance companies will be successful offering such an innovative insurance plan and will even out-compete companies offering only traditional plans. Furthermore, there will be substantial benefits that go beyond the cost savings. With both cost savings and patient welfare being central in the health care reform being proposed by the Obama administration, the dual choice plan offers considerable benefits.

System-size independence of directed flow measured at the BNL relativistic heavy-ion collider

We measure directed flow (v_{1}) for charged particles in Au+Au and Cu+Cu collisions at sqrt[s_{NN}]=200 and 62.4 GeV, as a function of pseudorapidity (eta), transverse momentum (p_{t}), and collision centrality, based on data from the STAR experiment. We find that the directed flow depends on the incident energy but, contrary to all available model implementations, not on the size of the colliding system at a given centrality. We extend the validity of the limiting fragmentation concept to v_{1} in different collision systems, and investigate possible explanations for the observed sign change in v_{1}(p_{t}).

Self-assembling peptide nanofiber as potential substrates in islet transplantation

Hypoxia and reoxygenation (H/R)-induced damage often happens soon after islets are transplantation. The process of islet isolation and purification causes the rapid onset of hypoxia. We sought to develop a functional scaffold to sustain the structure and function of islets as well as to recover some of the surface molecules damaged during isolation, seeking to improve islet transplantation outcomes. Self-assembling peptide nanofiber (SAPNF), a new type of substrate has been shown to be an excellent biological material for neuronal cell culture and tissue engineering in animals. In this study, we investigated the protective effect of SAPNF on damage to rat islets. Freshly prepared rat islets from male Sprague-Dawley rats were seeded in plates coated with (SAPNF-treated group) or without (control group) SAPNF. The islets were then divided into two groups culture under normoxia for 7 days versus exposure to hypoxia (< 1% O2) for 6 hours followed by reoxygenation for 24 hours. The results showed that SAPNF exhibited improving effects on viability and function of cultured islets, protecting the one from H/R-induced damage. In both groups, the stimulation index of SAPNF-treated groups were about two times the controls. SAPNF treatment decreased apoptotic rates of islet cells. These results suggested the usefulness of SAPNF to maintain the viability and function of rat pancreatic islets. SAPNF may be a potential scaffold for clinical islet transplantation.

Cloning, sequencing, and analysis of the full-length CDNA of rhesus monkey factor IX

OBJECTIVE

Coagulation factor IX (FIX) is a vitamin K-dependent serine protease, which plays a key role in the coagulation cascade. The rhesus monkey may be an indispensable substitute for humans in research of pig-to-human xenotransplantation, due to its close relationship. But the coagulation function concordance between rhesus monkey and human is unknown. In this study, we cloned the full-length cDNA of rhesus monkey FIX (rFIX) to investigate the genomic backgrounds of the coagulation systems.

METHOD

We cloned the full-length cDNA from the cDNA library of rhesus monkey liver tissue. Polymerase chain reaction was used to screen the positive clones. Based on a partial sequence obtained by cDNA library screening and a homologous sequence from the database, we designed a second pair of primers to obtain the full sequence. For further analysis of rFIX, we used several online ExPASy Proteomic tools.

RESULT

We obtained the full-length cDNA of rFIX, which has 2668 nucleotides, predicting an open reading frame of 1383 nucleotides corresponding to 461 amino acids. The deduced protein sequence indicated functional domains of signal peptide, Gla, two epidermal growth factor, and trypsin-like serine protease, which were consisted with those of human FIX (hFIX). Sequence alignments showed that rFIX is highly homologous to hFIX with nucleotide identity of 96% and amino acid identity of 97%.

CONCLUSION

We have report herein the full-length cDNA of rFIX. The high homology between rhesus monkey and human coagulation factor ensure the reliability and feasibility of rhesus monkey as a recipient in studies on coagulation disorders in xenotransplantation.

Forward neutral-pion transverse single-spin asymmetries in p + p collisions at sqrt[s] = 200 GeV

We report precision measurements of the Feynman x (xF) dependence, and first measurements of the transverse momentum (pT) dependence, of transverse single-spin asymmetries for the production of pi0 mesons from polarized proton collisions at sqrt[s] = 200 GeV. The xF dependence of the results is in fair agreement with perturbative QCD model calculations that identify orbital motion of quarks and gluons within the proton as the origin of the spin effects. Results for the pT dependence at fixed xF are not consistent with these same perturbative QCD-based calculations.

Insulin-like growth factor-1 receptor polymorphism and ischemic stroke: a case-control study in Chinese population

OBJECTIVES

Low levels of insulin-like growth factor 1 (IGF-1) are associated with atherosclerosis, and insulin-like growth factor-1 receptor (IGF-1R) polymorphisms can change plasma levels of IGF-1 and may alter the function of the receptor. Whether there is any association of genetic variation in IGF-1R gene with ischemic stroke (IS) is presently unknown.

MATERIALS AND METHOD

A 1:1 case-control study was conducted. The G --> A polymorphism of IGF-1R gene (rs2229765) were analyzed by TaqMan SNP genotyping technique in Chinese patients with IS (n = 309) and old subjects without IS (n = 309).

RESULTS

The frequency of A allele in the patients and controls was 45.79% and 39.64%, respectively. The AA genotype distribution of IGF-1R gene was significantly higher in the patients (27.51%) than controls (18.23%; P = 0.022). Conditional logistic regression revealed that the AA genotype of IGF-1R was associated with IS (OR = 1.641, P = 0.022). After adjustment for smoking, alcohol drinking, history of hypertension, and body mass index, IGF-1R AA genotype was still significantly associated with an increased risk of IS (OR = 1.787, P = 0.029), compared with IGF-1R GG.

CONCLUSIONS

The G --> A polymorphism in IGF-1R gene may affect the susceptibility to IS in Chinese population.