Enhanced production of direct photons in Au + Au collisions at square root(S(NN)) = 200 GeV and implications for the initial temperature

The production of e+ e- pairs for m(e+ e-)<0.3 GeV/c2 and 1<p(T)<5 GeV/c is measured in p+p and Au+Au collisions at square root(S(NN))=200 GeV. An enhanced yield above hadronic sources is observed. Treating the excess as photon internal conversions, the invariant yield of direct photons is deduced. In central Au+Au collisions, the excess of the direct photon yield over p+p is exponential in transverse momentum, with an inverse slope T=221+/-19(stat)+/-19(syst) MeV. Hydrodynamical models with initial temperatures ranging from T(init) approximately 300-600 MeV at times of approximately 0.6-0.15 fm/c after the collision are in qualitative agreement with the data. Lattice QCD predicts a phase transition to quark gluon plasma at approximately 170 MeV.

Exopolysaccharide analysis of biofilm-forming Candida albicans

AIM

The major objective of the study was to analyse exopolysaccharide produced by a biofilm forming-clinical strain of Candida albicans.

METHODS AND RESULTS

The biofilm-forming ability of C. albicans recovered from infected intrauterine devices (IUDs) was evaluated using XTT (2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide) reduction assay. The morphological characteristics of the biofilm were assessed using scanning electron microscopy (SEM), atomic force microscopy (AFM) and confocal laser scanning microscopy (CLSM). Biochemical characterization of the exopolysaccharide was carried out by gel permeation chromatography, gas chromatography (GC), Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. Microscopic studies of C. albicans biofilm revealed complex, heterogeneous three-dimensional structure, in which yeast cells and hyphal elements were entrenched within exopolysaccharides matrix. Chromatographic analysis data indicated C. albicans exopolysaccharide (c. 300 kDa) to be made up of four major sugar units. The FTIR spectrum revealed specific absorbance of O-H, C-H, O=C=O, C=O, C-N and C-C ring stretching. (1) H and (13) C NMR data showed the presence of β (1→6) and β (1→3) linkages in the exopolysaccharide chain that were assigned to α-D-glucose and β-D-glucose, α-D-mannose, α-L-rhamnose and N-acetyl glucosamine (β-D-GlcNAc), respectively.

CONCLUSIONS

Study suggested the production of a water soluble c. 300 kDa exopolysaccharide by C. albicans made up of glucose, mannose, rhamnose and N-acetyl glucosamine subunits.

SIGNIFICANCE AND IMPACT OF THE STUDY

The study could assist in the development of novel therapeutics aimed at disrupting C. albicans biofilms that will translate into improved clearance of Candida-related infections.

Charged Kaon interferometric probes of space-time evolution in Au+Au collisions at sqrt[S(NN)]=200 GeV

Bose-Einstein correlations of charged kaons are used to probe Au+Au collisions at sqrt[S(NN)]=200 GeV and are compared to charged pion probes, which have a larger hadronic scattering cross section. Three-dimensional Gaussian source radii are extracted, along with a one-dimensional kaon emission source function. The centrality dependences of the three Gaussian radii are well described by a single linear function of N(part)1/3 with a zero intercept. Imaging analysis shows a deviation from a Gaussian tail at r greater than or approximately equal to 10 fm, although the bulk emission at lower radius is well described by a Gaussian. The presence of a non-Gaussian tail in the kaon source reaffirms that the particle emission region in a heavy-ion collision is extended, and that similar measurements with pions are not solely due to the decay of long-lived resonances.

A study of viral hepatitis during pregnancy in Nepal Medical College Teaching Hospital

The present study aimed to find out prevalence and severity of viral hepatitis during pregnancy in the department of Obstetrics and Gynaecology, Nepal Medical College Teaching Hospital. Out of 5602 pregnant women admitted in the ward from 2001-2007; viral hepatitis was seen in 29 cases. HBV was detected in 18/29 (62.0%), HEV in 6/29 (20.6%) and viral hepatitis of undetected serology was seen in 5/29 (17.2%). Serology was undetected in these cases because of financial constraints. The mortality rate was 8/29 (27.5%). Three out of eight cases who expired were HEV positive and five were of undetected serology. Seven out of 8 maternal deaths were in preterm gestation and undelivered. Fulminant hepatitis with hepatic encephalopathy was the commonest cause of death. Hepatitis E was the commonest etiological agent in those who had fulminant disease during pregnancy and was associated with high mortality rate.

Measurement of bottom versus charm as a function of transverse momentum with electron-hadron correlations in p + p collisions at square root of s = 200 GeV

The momentum distribution of electrons from semileptonic decays of charm and bottom quarks for midrapidity |y|<0.35 in p+p collisions at square root of s=200 GeV is measured by the PHENIX experiment at the Relativistic Heavy Ion Collider over the transverse momentum range 2<pT<7 GeV/c. The ratio of the yield of electrons from bottom to that from charm is presented. The ratio is determined using partial D/D-->e(+/-)K(-/+)X (K unidentified) reconstruction. It is found that the yield of electrons from bottom becomes significant above 4 GeV/c in pT. A fixed-order-plus-next-to-leading-log perturbative quantum chromodynamics calculation agrees with the data within the theoretical and experimental uncertainties. The extracted total bottom production cross section at this energy is sigma(bb)=3.2(-1.1)(+1.2)(stat)(-1.3)(+1.4)(syst)mub.

Gluon-spin contribution to the proton spin from the double-helicity asymmetry in inclusive pi0 production in polarized p+p collisions at [sqrt]s=200 GeV

The double helicity asymmetry in neutral pion production for pT=1 to 12 GeV/c was measured with the PHENIX experiment to access the gluon-spin contribution, DeltaG, to the proton spin. Measured asymmetries are consistent with zero, and at a theory scale of micro2=4 GeV2 a next to leading order QCD analysis gives DeltaG[0.02,0.3]=0.2, with a constraint of -0.7<DeltaG[0.02,0.3]<0.5 at Deltachi2=9 (approximately 3sigma) for the sampled gluon momentum fraction (x) range, 0.02 to 0.3. The results are obtained using predictions for the measured asymmetries generated from four representative fits to polarized deep inelastic scattering data. We also consider the dependence of the DeltaG constraint on the choice of the theoretical scale, a dominant uncertainty in these predictions.

Effect of acute hepatitis E infection in patients with liver cirrhosis

INTRODUCTION

Hepatitis E virus is a major cause of enterically transmitted hepatitis. Mortality is very high if it is associated with pregnancy, especially during third trimester. This study was carried out to find out the effects of acute HEV hepatitis on Chronic Liver Disease patients of different etiologies.

METHODS

The consecutive patients of liver cirrhosis with definite evidence of recent HEV infection were enrolled in this study. Acute hepatitis was diagnosed by presence of prodromal symptoms and anti-HEV IgM antibody in their serum. The outcomes after superinfection with HEV hepatitis were determined by changes in Child Pugh score, recovery of liver function test, hospital stay and mortality.

RESULTS

After exclusion 25 were studied. The etiology of cirrhosis in patients was: alcohol 13, autoimmune hepatitis 3, hepatitis B 2, Budd Chiari syndrome 2, alcohol plus hepatitis B 1, hepatitis C 1, cardiac cirrhosis 1, Wilson's disease 1 and cryptogenic 1. All patients with no recent decompensation showed signs of decompensation during admission. Seven (28%) patients died. The cause of death was either upper gastrointestinal bleeding or hepatorenal syndrome. Remaining patients had prolonged hospital stay with deterioration of Child-Pugh's score.

CONCLUSIONS

Superinfection of HEV in cirrhotic patient causes rapid decompensation. The morbidity and mortality is higher compared to those non-infected patients. Development of hepatorenal syndrome and upper GI bleeding was commonest cause of death.

Effect of Acute Hepatitis E Infection in Patients with Liver Cirrhosis

Introduction: Hepatitis E virus is a major cause of enterically transmitted hepatitis. Mortality is veryhigh if it is associated with pregnancy, especially during third trimester. This study was carried out tofi nd out the effects of acute HEV hepatitis on Chronic Liver Disease patients of different etiologies.Methods: The consecutive patients of liver cirrhosis with defi nite evidence of recent HEV infectionwere enrolled in this study. Acute hepatitis was diagnosed by presence of prodromal symptomsand anti-HEV IgM antibody in their serum. The outcomes after superinfection with HEV hepatitiswere determined by changes in Child Pugh score, recovery of liver function test, hospital stay andmortality.Results: After exclusion 25 were studied. The etiology of cirrhosis in patients was: alcohol 13,autoimmune hepatitis 3, hepatitis B 2, Budd Chiari syndrome 2, alcohol plus hepatitis B 1, hepatitis C1, cardiac cirrhosis 1, Wilson’s disease 1 and cryptogenic 1. All patients with no recent decompensationshowed signs of decompensation during admission. Seven (28%) patients died. The cause of deathwas either upper gastrointestinal bleeding or hepatorenal syndrome. Remaining patients hadprolonged hospital stay with deterioration of Child-Pugh’s score.Conclusions: Superinfection of HEV in cirrhotic patient causes rapid decompensation. The morbidityand mortality is higher compared to those non-infected patients. Development of hepatorenalsyndrome and upper GI bleeding was commonest cause of death.Key Words: acute HEV infection, Chronic liver disease, third trimester pregnancy

The addiction Stroop task: examining the fast and slow effects of smoking and marijuana-related cues

Research has shown that attentional bias toward smoking-related stimuli is related to the maintenance of smoking behaviour and the chance of a relapse during a quit attempt. Effects of smoking attentional bias can occur both during smoking stimulus presentation (fast effect) and on stimuli that immediately follow smoking stimuli (slow effect). The current research builds on these findings by closely examining the temporal aspects of these fast and slow effects across groups of different smoking status. In Experiment 1 (n = 64), smokers, smokers attempting to quit (SATQ) and non-smokers completed an addiction Stroop task using smoking related, negative emotion and neutral stimuli. In Experiment 2 (n = 32), marijuana smokers and non-marijuana smokers completed an addiction Stroop task using marijuana and neutral stimuli. Results showed fast effects across all smoking groups (except non-smokers) and slow effects in SATQ and marijuana smokers. Furthermore, marijuana smokers showed slow effects over extended periods of time. Results also show a relationship between anxiety, nicotine dependence and attentional bias in SATQ. The implications of these findings are discussed.

Evaluation of skin graft take following post-burn raw area in normovolaemic anaemia

Background: Traditional wisdom is that wound healing is directly related to haemoglobin level in the blood; therefore blood transfusion is given in anaemic patients to raise the haemoglobin level for better wound healing. Methods: Evaluation of wound healing in the form of split thickness skin graft take was done in 35 normovolaemic anaemic patients (haemoglobin level of < 10 gm/ dl) and compared with control group (patients with haemoglobin level of 10 or > 10 gm/ dl). Results: There was no statistically significant difference in mean graft take between the two groups. Conclusion: It is not mandatory to keep haemoglobin level at or >10 g/dL or PCV value at or >30% for skin graft take, as mild to moderate anaemia per se does not cause any deleterious effect on wound healing; provided perfusion is maintained by adequate circulatory volume. Prophylactic transfusion to increase the oxygen carrying capacity of the blood for the purpose of wound healing is not indicated in asymptomatic normovolemic anaemic patients (with haemoglobin levels greater than 6g/dL) without significant cardiovascular or pulmonary disease.

Using epigenetic reprogramming to target triple-negative breast cancer

e14565

Background: The outcome for patients with breast cancer has been significantly improved by the use of targeted agents. The prognosis of triple negative (TN) breast cancers, which do not express hormone receptors (ER, PR) or Her2, is poor, because of an aggressive clinical course and lack of targeted therapeutic agents. Epigenetic silencing of specific genes has been observed in breast cancer and some of these genes are more important due to available targeted therapies such as ER. Since all endocrine therapies are designed to block ER function in some way, the identification of new therapies or strategies that could sensitize TN breast cancers to existing endocrine therapy could provide a revolutionary means of treating this aggressive subtype of cancer Methods: We examined the efficacy of combined treatment of HDAC inhibitor LBH589 and DNMT inhibitor decitabine to regenerate ER and PR in TN breast cancer cells using RT-PCR and immunoblotting. Changes in growth and proliferation of TN breast cancer cells in response to LBH589 and decitabine treatment were determined by XTT, BrdU incorporation and colony formation assay. Changes in apoptotic proteins were determined by western blotting. Athymic nude mice were used to establish pre-clinical models for TN breast cancer cells and effectiveness of combined treatment of LBH589 and decitabine was determined. Tumors biopsies were analyzed for ER and PR re-expression by western blot analysis and immunohistochemistry at the end of the treatment. Results: Combined treatment of LBH589 and decitabine resulted in re-expression of ER and PR in TN breast cancers in vitro and in vivo. Although re-expression of ER and PR were noted following LBH589 treatment alone, re-expression was more robust with the combination. TN breast cancer cells showing re-expressed ER can be targeted with tamoxifen. Tamoxifen inhibits growth of TN breast cancer cells re- expressing ER by triggering apoptosis. Conclusions: The importance of epigenetic events such as DNA methylation and HDAC inhibition in tumor progression is becoming increasingly evident. A trial evaluating the ability of LBH589 and decitabine to re- express ER, which can then be targeted by tamoxifen, is planned in patients with metastatic TN breast cancer.

No significant financial relationships to disclose.

Co-targeting leptin and insulin-like growth factor I signaling: dramatic effects of epidermal growth factor receptor inhibitors on triple negative breast cancer cells

Abstract #3044

Introduction: Obesity is an independent risk factor for breast cancer and obese breast cancer patients exhibit a higher risk for larger tumor burden, increased metastasis and poor response to endocrine therapy. Obesity affects breast carcinogenesis by autocrine and paracrine effects of adipocytokine leptin and IGF-1. We have previously shown that leptin induces growth stimulation of breast cancer cells by recruiting histone acetyltransferases and mediator complex to cyclin D1 promoter via activation of Stat3. In the present study, we found a novel bidirectional crosstalk between IGF-1 and leptin signaling that promotes invasion and migration of triple-negative (ER, PR, HER2 negative) breast cancer cells; MDA-MB-231, MDA-MB-468, MDA-MB-435 and HCC-1806.&#x2028; Methods and Results: IGF-1 induced significant tyrosine phosphorylation of leptin receptor (Ob-Rb) and leptin induced tyrosine phosphorylation of IGF-1 Receptor (IGF-1R). Combined treatment of leptin and IGF-1 induced synergistic activation of both Ob-Rb and IGF-1R along with activation of Akt and ERK. Furthermore, IGF-1 and leptin synergistically transactivated epidermal growth factor receptor (EGFR) and induced proliferation of triple negative breast cancer cells. We also found that tyrosine phosphorylation of EGFR induced by combined treatment of leptin and IGF-1 was significantly inhibited not only by EGFR tyrosine kinase inhibitor, AG1478 but also with a broad-spectrum matrix metalloproteinase inhibitor, GM6001 indicating that leptin and IGF-1 induced EGFR transactivation is dependent on proteolytic release of EGFR ligands. Intriguingly, we also found that combined treatment of leptin and IGF-1 potently induced invasion of triple negative breast cancer cells in Matrigel invasion and quantitative Electric Cell-Substrate Impedance Sensing invasion assays. Inhibition of leptin and IGF-1 mediated EGFR activation using a highly potent, reversible inhibitor of HER1/EGFR tyrosine kinase, erlotinib or dual epidermal growth factor receptor (EGFR)/human EGFR-2 (HER2) kinase inhibitor, lapatinib effectively inhibited leptin and IGF-1 induced invasion. Also, inhibition of EGFR activation using erlotinib and lapatinib reduced leptin- and IGF-1-induced migration of triple negative breast cancer cells.&#x2028; Discussion: Taken together these data indicate a novel bidirectional crosstalk between leptin and IGF-1 signaling that transactivates EGFR and promotes metastatic properties, invasion and migration of triple negative breast carcinoma cells. Our novel findings indicate the possibility of using EGFR inhibitors erlotinib and lapatinib to counter the pro-cancerous effects of leptin and IGF-1 signaling in triple negative breast cancers.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 3044.