Search for neutral minimal supersymmetric standard model Higgs bosons decaying to tau pairs produced in association with b quarks in pp collisions at √s = 1.96 TeV

We report results from a search for neutral Higgs bosons produced in association with b quarks using data recorded by the D0 experiment at the Fermilab Tevatron Collider and corresponding to an integrated luminosity of 7.3 fb(-1). This production mode can be enhanced in several extensions of the standard model (SM) such as in its minimal supersymmetric extension (MSSM) at high tanβ. We search for Higgs bosons decaying to tau pairs with one tau decaying to a muon and neutrinos and the other to hadrons. The data are found to be consistent with SM expectations, and we set upper limits on the cross section times branching ratio in the Higgs boson mass range from 90 to 320 GeV/c(2). We interpret our result in the MSSM parameter space, excluding tanβ values down to 25 for Higgs boson masses below 170 GeV/c(2).

Precision measurement of the ratio B(t→Wb)/B(t→Wq) and extraction of V(tb)

We present a measurement of the ratio of top quark branching fractions R=B(t→Wb)/B(t→Wq), where q can be a d, s, or b quark, in the lepton+jets and dilepton tt final states. The measurement uses data from 5.4 fb(-1) of pp collisions collected with the D0 detector at the Fermilab Tevatron Collider. We measure R=0.90±0.04, and we extract the Cabibbo-Kobayashi-Maskawa (CKM) matrix element |V(tb)| as |V(tb)|=0.95±0.02, assuming unitarity of the 3×3 CKM matrix.

Eclampsia-scenario in a hospital--a ten years study

This cross sectional record based institutional study was conducted in the Department of Obstetrics & Gynaecology, Burdwan Medical College, Burdwan over ten years (1999-2008) aiming analysis of eclamptic mothers for evaluation of maternal and perinatal outcome with different anticonvulsant medications. Total 5991 pregnant mothers with eclampsia admitted in the inpatient department of the tertiary care teaching hospital were recruited for the study, irrespective of their previous antenatal check up history. Subjects with known seizure disorders were excluded from the study. The subjects were managed according to standard regimens (Menon, Ph-sodium, diazepam & magnesium sulphate) and results were documented in standardised format. Case fatality rate, mean induction delivery time & birth-weight, perinatal mortality rates were recorded. Study reveals that the incidence of eclampsia <20 years was 6.97% and majority (5.41%) came from rural areas. Eclampsia was noted primarily in primigravida (7.43%) and unbooked (6.41%) mothers. Ante partum eclampsia predominated (64%) and incidence of caesarean section was 22.25%.The overall case fatality rate was 6.05% and eclampsia contributed 27.85% of all maternal deaths during the last two years of the study period. The overall incidence of low birth weight baby was 26.96% and perinatal mortality was 30.33% (1411/4651).The incidence of perinatal mortality and low birth weight babies are lower in the last 4 years when compared to earlier studies. Proper socio-demographic assessment of pregnancy with eclampsia, planned delivery, shorter induction delivery interval, good control of convulsion by magnesium sulphate, intensive intranatal monitoring causes less maternal and perinatal morbidity and mortality.

Search for a fourth generation t' Quark in p ̄p collisions at √s = 1.96 TeV

We present a search for pair production of a fourth generation t' quark and its antiparticle, followed by their decays to a W boson and a jet, based on an integrated luminosity of 5.3 fb(-1) of proton-antiproton collisions at √s = 1.96  TeV collected by the D0 Collaboration at the Fermilab Tevatron Collider. We set upper limits on the t' ̄t' production cross section that exclude at the 95% C.L. a t' quark that decays exclusively to W+jet with a mass below 285 GeV. We observe a small excess in the μ+jets channel which reduces the mass range excluded compared to the expected limit of 320 GeV in the absence of a signal.

Precise measurement of the top quark mass in the dilepton channel at D0

We measure the top quark mass (m(t)) in p ̄p collisions at a center of mass energy √s = 1.96 TeV using dilepton t ̄t→W(+)bW(-) ̄b→ℓ(+)ν(ℓ)bℓ(-) ̄ν(ℓ) ̄b events, where ℓ denotes an electron, a muon, or a tau that decays leptonically. The data correspond to an integrated luminosity of 5.4 fb(-1) collected with the D0 detector at the Fermilab Tevatron Collider. We obtain m(t)=174.0±1.8(stat)±2.4(syst) GeV, which is in agreement with the current world average m(t)=173.3±1.1 GeV. This is currently the most precise measurement of m(t) in the dilepton channel.

Measurement of spin correlation in tt production using a matrix element approach

We determine the fraction of tt events with spin correlation, assuming that the spin of the top quark is either correlated with the spin of the top antiquark as predicted by the standard model or is uncorrelated. For the first time we use a matrix-element-based approach to study tt spin correlation. We use tt → W+ b W- b → ℓ+ νbℓ- ν b final states produced in pp collisions at a center-of-mass energy sqrt(s)=1.96  TeV, where ℓ denotes an electron or a muon. The data correspond to an integrated luminosity of 5.4  fb(-1) and were collected with the D0 detector at the Fermilab Tevatron collider. The result agrees with the standard model prediction. We exclude the hypothesis that the spins of the tt are uncorrelated at the 97.7% C.L.

Anticataleptic and antiepileptic activity of ethanolic extract of leaves of Mucuna pruriens: A study on role of dopaminergic system in epilepsy in albino rats

Objective:

To assess the anticataleptic and antiepileptic activity of leaves of Mucuna pruriens in albino rats.

Materials and Methods:

Haloperidol-induced catalepsy (HIC), maximum electro-shock (MES) method, pilocarpine-induced Status epilepticus (PISE) and single-dose effect of M. pruriens were employed.

Results:

M. pruriens (100 mg/kg) had significant anticataleptic and antiepileptic activity in HIC, MES, and PISE.

Conclusions:

M. pruriens extract has the potential to be an anticataleptic and antiepileptic drug. Dopamine and 5-HT may have a role in such activity.

Bounds on an anomalous dijet resonance in W+jets production in pp collisions at √s = 1.96 TeV

We present a study of the dijet invariant mass spectrum in events with two jets produced in association with a W boson in data corresponding to an integrated luminosity of 4.3 fb(-1) collected with the D0 detector at √s = 1.96 TeV. We find no evidence for anomalous resonant dijet production and derive upper limits on the production cross section of an anomalous dijet resonance recently reported by the CDF Collaboration, investigating the range of dijet invariant mass from 110 to 170 GeV/c(2). The probability of the D0 data being consistent with the presence of a dijet resonance with 4 pb production cross section at 145 GeV/c(2) is 8×10(-6).

Prenatal complex rhythmic music sound stimulation facilitates postnatal spatial learning but transiently impairs memory in the domestic chick

Early experience has a profound influence on brain development, and the modulation of prenatal perceptual learning by external environmental stimuli has been shown in birds, rodents and mammals. In the present study, the effect of prenatal complex rhythmic music sound stimulation on postnatal spatial learning, memory and isolation stress was observed. Auditory stimulation with either music or species-specific sounds or no stimulation (control) was provided to separate sets of fertilized eggs from day 10 of incubation. Following hatching, the chicks at age 24, 72 and 120 h were tested on a T-maze for spatial learning and the memory of the learnt task was assessed 24 h after training. In the posthatch chicks at all ages, the plasma corticosterone levels were estimated following 10 min of isolation. The chicks of all ages in the three groups took less (p < 0.001) time to navigate the maze over the three trials thereby showing an improvement with training. In both sound-stimulated groups, the total time taken to reach the target decreased significantly (p < 0.01) in comparison to the unstimulated control group, indicating the facilitation of spatial learning. However, this decline was more at 24 h than at later posthatch ages. When tested for memory after 24 h of training, only the music-stimulated chicks at posthatch age 24 h took a significantly longer (p < 0.001) time to traverse the maze, suggesting a temporary impairment in their retention of the learnt task. In both sound-stimulated groups at 24 h, the plasma corticosterone levels were significantly decreased (p < 0.001) and increased thereafter at 72 h (p < 0.001) and 120 h which may contribute to the differential response in spatial learning. Thus, prenatal auditory stimulation with either species-specific or complex rhythmic music sounds facilitates spatial learning, though the music stimulation transiently impairs postnatal memory.

Hepatoprotective Effects and Safety Evaluation of Coumarinolignoids Isolated from Cleome viscosa Seeds

The aim of the present work was to investigate the in vivo hepatoprotective potential of coumarinolignoids (cleomiscosins A, B, and C) isolated from the seeds of C. viscosa. The study was performed against CCl(4)-induced hepatotoxicity in albino rats. Rats were divided into four groups. The animals of group I served as normal and was given only vehicle. Group II served as toxin control and administered with CCl(4) (50% solution liquid paraffin, 2 ml/kg intraperitoneally). The animals of group III received coumarinolignoids (50 mg/kg) for six days orally as well as CCl(4) (2 ml/kg) on 4(th) day i.p. Similarly animals of group IV received silymarin (50 mg/kg) for six days orally as well as CCl(4) on 4(th) day i.p. On 7(th) day various parameters viz. serum glutamyl oxaloacetic transaminase, serum glutamyl pyruvate transaminase, serum alkaline phosphatase, serum bilirubin, liver glycogen were estimated and histopathology was performed. Additionally, acute oral toxicity of the said coumarinolignoids was carried out in swiss albino mice. The coumarinolignoids were found to be effective as hepatoprotective against CCl(4)-induced hepatotoxicity as evidenced by in vivo and histopathological studies in small animals. Safety evaluation studies also exhibit that coumarinolignoids are well tolerated by small animals in acute oral toxicity study except minor changes in red blood cell count and hepatic protein content at 5000 mg/kg body weight as a single oral dose. Coumarinolignoids which is the mixture of three compounds (cleomiscosin A, B and C) is showing the significant protective effects against CCl(4)-induced hepatotoxicity in small animals and also coumarinolignoids are well tolerated by small animals in acute oral study.

Adenovirus 5 E1A enhances histone deacetylase inhibitors-induced apoptosis through Egr-1-mediated Bim upregulation

Histone deacetylase inhibitors (HDACi) are potent anti-cancer agents for variety of cancer types. Suberoylanilide hydroxamic acid (SAHA) has been approved as a drug to treat cutaneous T cell lymphoma, and the combination of HDACi and other agents have been actively tested in many clinical trials. Adenovirus 5 early region 1A (E1A) has been shown to exhibit high tumor suppressor activity, and gene therapy using E1A has been tested in clinical trials. Here, we showed that proapoptotic activity of HDACi was robustly enhanced by E1A in multiple cancer cells, but not in normal cells. Moreover, we showed that combination of E1A gene therapy and SAHA showed high therapeutic efficacy with low toxicity in vivo ovarian and breast xenograft models. SAHA downregulated Bcl-XL and upregulated proapoptotic BH3-only protein Bim, whose expression was further enhanced by E1A in cancer cells. These alterations of Bcl-2 family proteins were critical for apoptosis induced by the combination in cancer cells. SAHA enhanced acetylation of histone H3 in Bim promoter region, while E1A upregulated Egr-1, which was directly involved in Bim transactivation. Together, our results provide not only a novel insight into the mechanisms underlying anti-tumor activity of E1A, but also a rationale for the combined HDACi and E1A gene therapy in future clinical trials.

Superior mesenteric artery syndrome in association with an abdominal aortic aneurysm

Superior mesenteric artery (SMA) syndrome, also known as Wilkie syndrome, is a rare condition characterised by compression of the third part of the duodenum against the aorta by the SMA. This can cause symptomatic duodenal obstruction. It is rarely associated with an abdominal aortic aneurysm (AAA). We report the case of a male patient presenting with an AAA and recurrent upper gastrointestinal symptoms. SMA syndrome was diagnosed with imaging and was then successfully treated by aneurysm repair. This is the smallest AAA associated with SMA syndrome in the literature. We propose an anatomical mechanism for SMA syndrome in this case.

Speeds of Sound and Isentropic Compressibilities of Diethylene Glycol Dimethyl Ether - n-Alcohol Mixtures at 298.15 K

The speeds of sound has been obtained at a frequency of 4 MHz in diethylene glycol dimethyl ether + methanol, + ethanol, + 1-butanol, and + 1-pentanol across the entire composition range, at the temperature 298.15 K and atmospheric pressure using a NUSONIC velocimeter based on the sing-around technique. The ultrasonic speed values have been combined with those of the excess molar volumes converted to densities to obtain estimates of the product KS,m of the molar volumes and isentropic compressibility κS, and excess quantity KE S,m. The KE S,m values are negative over the entire range of composition for all mixtures with the exception of 1-pentanol, which changes sign from positive to negative. The magnitude of KE S,m increase with the number of carbon atoms in the n-alcohol. The deviations of the speeds of sound uD from their ideal values uid in an ideal mixture were also calculated for all measured mole fractions. The behaviour of u, uD, and KE S,m with composition and the number of carbon atoms in the alcohol molecule is discussed.

Effects of clonidine and sumatriptan on postprandial gastric volume response, antral contraction waves and emptying: an MRI study

Gastric emptying (GE) may be driven by tonic contraction of the stomach ('pressure pump') or antral contraction waves (ACW) ('peristaltic pump'). The mechanism underlying GE was studied by contrasting the effects of clonidine (alpha(2)-adrenergic agonist) and sumatriptan (5-HT(1) agonist) on gastric function. Magnetic resonance imaging provided non-invasive assessment of gastric volume responses, ACW and GE in nine healthy volunteers. Investigations were performed in the right decubitus position after ingestion of 500 mL of 10% glucose (200 kcal) under placebo [0.9% NaCl intravenous (IV) and subcutaneous (SC)], clonidine [0.01 mg min(-1) IV, max 0.1 mg (placebo SC)] or sumatriptan [6 mg SC (placebo IV)]. Total gastric volume (TGV) and gastric content volume (GCV) were assessed every 5 min for 90 min, interspersed with dynamic scan sequences to measure ACW activity. During gastric filling, TGV increased with GCV indicating that meal volume dictates initial relaxation. Gastric contents volume continued to increase over the early postprandial period due to gastric secretion surpassing initial gastric emptying. Clonidine diminished this early increase in GCV, reduced gastric relaxation, decreased ACW frequency compared with placebo. Gastric emptying (GE) rate increased. Sumatriptan had no effect on initial GCV, but prolonged gastric relaxation and disrupted ACW activity. Gastric emptying was delayed. There was a negative correlation between gastric relaxation and GE rate (r(2 )=49%, P < 0.001), whereas the association between ACW frequency and GE rate was inconsistent and weak (r2=15%, P = 0.05). These findings support the hypothesis that nutrient liquid emptying is primarily driven by the 'pressure pump' mechanism.

Synthesis of N3-substituted thymidine analogues for measurement of cellular kinase activity

N3-Substitued thymidine analogues that carry a carboranylalkyl moiety at the N3-position with various spacer lengths have been reported to be good substrates for thymidine kinase (TK1). As part of our continuing effort towards the development of new TK1 substrates for imaging tumor proliferative activity, we have synthesized a series of new N3-substituted analogues of thymidine that carry an aromatic ring with different spacer lengths. The overall yields for 6 and 7 were 13% and 39% in four steps and three steps, respectively, and those for 14, 16 and 18 were in the range of 13%-15% in six steps. The overall yield for 24 was 33% in three steps, and those for 25 and 26 were 64% and 58%, respectively, in one step. Most of these compounds have been tested for TK1 activity by enzymatic assay to identify a good substrate that can be radiolabeled for imaging. The phosphorylation rates of these compounds were 2%-6% compared with that of thymidine. The results from the in vitro enzymatic assays suggest that these N3-substituted thymidine analogues have some potential for imaging TK1 activity if radiolabeled with a suitable isotope.