Glutathione S-transferases YcYfetus and YcYc - kinetic and inhibitor studies relating to their glutathione peroxidase activities

The kinetic properties of the glutathione (GSH) peroxidase activities of GSH S-transferases YcYfetus and YcYc were compared. The catalytic efficiency of the fetal iso-enzyme with cumene hydroperoxide as substrate was approximately four times higher than the other. The effects of the non-substrate ligand rose-Bengal as well as the substrate ligands sulphobromophthalein and acrolein on the GSH peroxidase activity of these two iso-enzymes were also investigated. Depending on the ligand, the inhibition profiles of these two iso-enzymes when measured with either the peroxidase substrate, cumene hydroperoxide or the standard GSH S-transferase substrate 1:chloro-2,4-dinitrobenzene were found to be either very similar (sulphobromophthalein) or markedly different (rose Bengal and acrolein). Significantly, the GSH peroxidase activity of the fetal iso-enzyme was far less susceptible to inhibition by the teratogen, acrolein, than that of the YcYc isoenzyme. It is therefore attractive to suggest that should a similar situation arise in vivo, this resistance to peroxidase inhibition may play a role in preventing the fetotoxic effects of acrolein

Editorial: Hendrik Hanekom - innovator, facilitator and transformer

No Abstrac

Editorial: Why viral hepatitis?

No Abstrac

Synthesis of (1S)-N-(1-carboxy-5-aminopentyl)-glycylglycine - a prospective competitive inhibitor for angiotensin-converting enzyme

The synthesis of a prospective competitive inhibitor of angiotensin-converting enzyme, (1 S )-N-(1-carboxy-5- aminopentyllglycylglycine (4), was accomplished in four steps in 72% overall yield starting from glycine. Hydrogenolysis of the benzyl and benzyloxycarbonyl protective groups in the last step was enhanced by the use of ultrasound

National strategy for the prevention and management of transfusion-associated hepatitis

The screening of potential blood donors for the hepatitis B (HBV) and C (HCV) viruses has decreased the risk of transfusion-associated hepatitis, There remains. however, a lack of consensus on a number of issues including methods for screening of blood donors and the management of donors found to have markers of hepatitis virus infection. This document outlines the recommendations of a large group of interested individuals including blood transfusion service managers, primary care health authorities, epidemiologists, Virologists, pathologists, gastroenterologists and hepatologists drawn from both the public and the private sector

Serial measurements of circulating tissue plastninogen activator and fibrin(ogen) degradation products predict outcome in gestational proteinuric hypertension

Gestational proteinuric hypertension (GPH), a major cause of maternal death, may be characterised by hypertension and proteinuria alone or may progress to disturbed coagulation and multiorgan failure. Since the condition can only be reversed by termination of pregnancy, there is a need for reliable indicators of severity. We found circulating levels of tissue plasminogen activator (tPA)(27,98 ± 2,12 v. 7,17 ± 0,81 ng/ml, mean ± SEM), fibrin(ogen) degradation products (FDP) (7,55 ± 1,99 v. 1,92 ± 0,47 μg/ml) and fibronectin (221 ± 15,2 v. 120 ± 15,2 μg/ml) to be significantly increased in 21 patients with severe GPH when compared with 21 normotensive, age- and gestational age-matched pregnant controls. More importantly, patients who developed severe GPH showed a progressive increase in tPA and FDP levels with time. This was in contrast to patients who had hypertension and proteinuria alone, in whom tPA and FDP concentrations did not increase. Parallel measurements did not reveal a fall in platelet count or an increase in urinary protein excretion in patients who subsequently progressed to severe disease. Our findings may be of assistance to clinicians faced with the need to prolong pregnancy in patients with GPH in order to ensure fetal viability

Global Search for New Physics with 2.0/fb at CDF

Data collected in Run II of the Fermilab Tevatron are searched for indications of new electroweak-scale physics. Rather than focusing on particular new physics scenarios, CDF data are analyzed for discrepancies with the standard model prediction. A model-independent approach (Vista) considers gross features of the data, and is sensitive to new large cross-section physics. Further sensitivity to new physics is provided by two additional algorithms: a Bump Hunter searches invariant mass distributions for "bumps" that could indicate resonant production of new particles; and the Sleuth procedure scans for data excesses at large summed transverse momentum. This combined global search for new physics in 2.0/fb of ppbar collisions at sqrt(s)=1.96 TeV reveals no indication of physics beyond the standard model.Comment: 8 pages, 7 figures. Final version which appeared in Physical Review D Rapid Communication

Observation of Orbitally Excited B_s Mesons

We report the first observation of two narrow resonances consistent with states of orbitally excited (L=1) B_s mesons using 1 fb^{-1} of ppbar collisions at sqrt{s} = 1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. We use two-body decays into K^- and B^+ mesons reconstructed as B^+ \to J/\psi K^+, J/\psi \to \mu^+ \mu^- or B^+ \to \bar{D}^0 \pi^+, \bar{D}^0 \to K^+ \pi^-. We deduce the masses of the two states to be m(B_{s1}) = 5829.4 +- 0.7 MeV/c^2 and m(B_{s2}^*) = 5839.7 +- 0.7 MeV/c^2.Comment: Version accepted and published by Phys. Rev. Let

Search for single top quarks in the tau+jets channel using 4.8 fb−1^{-1} of ppˉp\bar{p} collision data

We present the first direct search for single top quark production using tau leptons. The search is based on 4.8 fb$^{-1}$ of integrated luminosity collected in $p\bar{p}$ collisions at $\sqrt{s}$=1.96 TeV with the D0 detector at the Fermilab Tevatron Collider. We select events with a final state including an isolated tau lepton, missing transverse energy, two or three jets, one or two of them $b$ tagged. We use a multivariate technique to discriminate signal from background. The number of events observed in data in this final state is consistent with the signal plus background expectation. We set in the tau+jets channel an upper limit on the single top quark cross section of \TauLimObs pb at the 95% C.L. This measurement allows a gain of 4% in expected sensitivity for the observation of single top production when combining it with electron+jets and muon+jets channels already published by the D0 collaboration with 2.3 fb$^{-1}$ of data. We measure a combined cross section of \SuperCombineXSall pb, which is the most precise measurement to date.Comment: 12 pages, 5 figure