[Survey of cardiovascular risk assessment and the behaviour of a sporting population]. / Enquête sur les comportements et l'évaluation du risque cardiovasculaire dans une population de sportifs.

In order to better understand the risk factors and behaviour of a general sports population, a questionnaire was handed to 603 consecutive sportsmen of various disciplines during a specific sports medicine consultation and a half-marathon. Among the discovered risk factors, smoking was the most common (19.3% for the entire study population), predominantly in the youngest group (26%). A resting ECG had been performed very frequently within the previous year in those over 40 years (86.5%), but less often in the younger sportsmen (44.8%). An exercise test had also very often been performed in those aged over 40 years (69.2 vs 10.6%). Behaviour associated with cardiovascular risk was common. Undertaking physical activity while febrile (58%) and smoking just before or after exertion (13.1%) were widespread behaviours. This population appeared casual in its approach to possibly suspicious cardiac symptoms of exercise, particularly the females and paradoxically the subjects doing the most sport. Lastly, only a minority of sportsmen knew the telephone number for the emergency medical service (45%) or claimed to be competent at first aid (32%). This survey underlines a practice relatively in accordance with the recommendations for detecting cardiovascular pathology, but shows a failure of preventive education.

Biochemical approaches to the synthesis of ethyl 5-(s)-hydroxyhexanoate and 5-(s)-hydroxyhexanenitrile.

Three different biochemical approaches were used for the synthesis of ethyl 5-(S)-hydroxyhexanoate 1 and 5-(S)-hydroxyhexanenitrile 2. In the first approach, ethyl 5-oxo-hexanoate 3 and 5-oxo-hexanenitrile 4 were reduced by Pichia methanolica (SC 16116) to the corresponding (S)-alcohols, ethyl (S)-5-hydroxyhexanoate 1 and 5-(S)-hydroxyhexanenitrile 2, with an 80-90% yield and >95% enantiomeric excess (e.e). In the second approach, racemic 5-hydroxyhexanenitrile 5 was resolved by enzymatic succinylation, leading to the formation of (R)-5-hydroxyhexanenitrile hemisuccinate and leaving the desired alcohol 5-(S)-hydroxyhexanenitrile 2 with a yield of 34% (50% maximum yield) and >99% e.e. In the third approach, enzymatic hydrolysis of racemic 5-acetoxy hexanenitrile 6 resulted in the hydrolysis of the R-isomer to provide 5-(R)-hydroxyhexanenitrile, leaving 5-(S)-acetoxyhexanenitrile 7 with a 42% yield (50% maximum yield) and >99% e.e.

A decrease in remodeling accounts for the accumulation of arachidonic acid in murine mast cells undergoing apoptosis.

The goal of this study was to examine arachidonic acid (AA) metabolism by murine bone marrow-derived mast cells (BMMC) during apoptosis induced by cytokine depletion. BMMC deprived of cytokines for 12-48 h displayed apoptotic characteristics. During apoptosis, levels of AA, but not other unsaturated fatty acids, correlated with the percentage of apoptotic cells. A decrease in both cytosolic phospholipase A(2) expression and activity indicated that cytosolic phospholipase A(2) did not account for AA mobilization during apoptosis. Free AA accumulation is also unlikely to be due to decreases in 5-lipoxygenase and/or cyclooxygenase activities, since BMMC undergoing apoptosis produced similar amounts of leukotriene B(4) and significantly greater amounts of PGD(2) than control cells. Arachidonoyl-CoA synthetase and CoA-dependent transferase activities responsible for incorporating AA into phospholipids were not altered during apoptosis. However, there was an increase in arachidonate in phosphatidylcholine (PC) and neutral lipids concomitant with a 40.7 +/- 8.1% decrease in arachidonate content in phosphatidylethanolamine (PE), suggesting a diminished capacity of mast cells to remodel arachidonate from PC to PE pools. Further evidence of a decrease in AA remodeling was shown by a significant decrease in microsomal CoA-independent transacylase activity. Levels of lyso-PC and lyso-PE were not altered in cells undergoing apoptosis, suggesting that the accumulation of lysophospholipids did not account for the decrease in CoA-independent transacylase activity or the induction of apoptosis. Together, these data suggest that the mole quantities of free AA closely correlated with apoptosis and that the accumulation of AA in BMMC during apoptosis was mediated by a decreased capacity of these cells to remodel AA from PC to PE.

Secretory phospholipase A2 receptor-mediated activation of cytosolic phospholipase A2 in murine bone marrow-derived mast cells.

The current study examined the signal transduction steps involved in the selective release of arachidonic acid (AA) induced by the addition of secretory phospholipase A2 (sPLA2) isotypes to bone marrow-derived mast cells (BMMC). Overexpression of sPLA2 receptors caused a marked increase in AA and PGD2 release after stimulation of BMMC, implicating sPLA2 receptors in this process. The hypothesis that the release of AA by sPLA2 involved activation of cytosolic PLA2 (cPLA2) was next tested. Addition of group IB PLA2 to BMMC caused a transient increase in cPLA2 activity and translocation of this activity to membrane fractions. Western analyses revealed that these changes in cPLA2 were accompanied by a time-dependent gel shift of cPLA2 induced by phosphorylation of cPLA2 at various sites. A noncatalytic ligand of the sPLA2 receptor, p-amino-phenyl-alpha-D-mannopyranoside BSA, also induced an increase in cPLA2 activity in BMMC. sPLA2 receptor ligands induced the phosphorylation of p44/p42 mitogen-activated protein kinase. Additionally, an inhibitor of p44/p42 mitogen-activated protein kinase (PD98059) significantly inhibited sPLA2-induced cPLA2 activation and AA release. sPLA2 receptor ligands also increased Ras activation while an inhibitor of tyrosine phosphorylation (herbimycin) inhibited the increase in cPLA2 activation and AA release. Addition of partially purified sPLA2 from BMMC enhanced cPLA2 activity and AA release. Similarly, overexpression of mouse groups IIA or V PLA2 in BMMC induced an increase in AA release. These data suggest that sPLA2 mediate the selective release of AA by binding to cell surface receptors and then inducing signal transduction events that lead to cPLA2 activation.

Mosquito larval density survey on Mahe in 1995

Our survey was carried out in the residential areas of Mahe island in 1995. Thirty to fifty houses from each of the 19 blocks lived in were randomly chosen and carefully checked both inside and outside within a circumference of 50 metres. Out of 974 water bodies; 461 were larval positive. Among the latter; 353 were found breeding larvae of Aedes albopictus ; 95 of Culex fatigans and 32 of Uranotania pandani. More than 3 species co-breeding were not found. Aedes aegypti was found three times only and all within St Louis. High density of Aedes albopictus puts Seychelles in great danger of having epidemics of yellow fever and dengue fever/dengue hemorrhagic fever. Its proportion has almost doubled from that of 25 years ago and was also higher than that of 1994. All entomological indices are many times higher than that associated with outbreaks of yellow fever. Flower pots and used containers are the main sources of domestic breeding. We are facing a great challenge in source reduction for mosquito control and need the co-operation and help of all people and agencies in Seychelles

Fermentation and isolation of C10-deacetylase for the production of 10-deacetylbaccatin III from baccatin III.

10-Deacetylabaccatin III (10 DAB), an important precursor for paclitaxel semisynthesis, is enhanced in yew extracts using C10-deacetylase and C13-deacylase enzymes.(4) C10-deacetylase is an intracellular enzyme produced by the fermentation of a soil microorganism, Nocardioides luteus (SC 13912). During the fermentation of Nocardioides luteus, the growth of cells reaches a maximum growth at 28 h. C10-deacetylase enzyme activity starts at 26 h and peaks at 38 h of the fermentation. The cells are recovered by centrifugation. The C10-deacetylase enzyme was purified from the Nocardioides luteus cells. The enzyme was purified 190-fold to near homogeneity. The purified enzyme appeared as a single band on 12.5% SDS-PAGE analysis with a molecular weight of 40,000 daltons. (c) 1995 John Wiley & Sons, Inc.

High density culture of HeLa cells in a CelliGen perfusion system.

A hollow fiber cartridge may be used in an extraneous recycle loop to facilitate perfusion operation of a stirred tank bioreactor. Retention of cells while removing waste products and replenishment with fresh nutrients allows higher than normal cell densities obtained in batch or continuous culture systems. This system successfully propagated HeLa cells to over 11 million viable cells per milliliter. Much higher perfusion rates (up to 4 vessel volumes per day) were necessary for high density culture of HeLa cells compared to BHK or a hybridoma cell line because of a much higher specific cellular metabolic rate. Cell specific glucose consumption rate, lactate production and ammonia production rates are several times higher for HeLa cells. Reproducible high cell densities and viabilities can be repeatedly obtained after harvest and dilution of a HeLa cell culture by partial drainage and reconstitution in the bioreactor.

[Computerized analysis of ST segment during exercise. Interpretation of "saw tooth" appearance]. / Traitement informatisé du segment ST au cours de l'effort. Interprétation d'un aspect en "dents de scie".

The authors report original appearances (sinusoid or "saw tooth" aspect) of computerised analysis of the ST segment in 3 cases, corresponding to ST changes during exercise stress testing. This is due to alternating ST elevation and depression probably related to abnormal vasomotor tone given the fact that the recording was normalised by coronary vasodilator therapy.

Anti-ischemic effects of celiprolol in patients with exercise-induced angina pectoris.

The anti-ischemic properties of the new cardioselective beta-adrenoreceptor antagonist celiprolol were investigated in an open study of 12 men (mean age: 58 +/- 6.6 years) with exercise-induced angina pectoris. After all previous anti-anginal medication had been withdrawn for at least 5 half-lives, the patients received placebo, single doses of nitroglycerin buccal spray, sublingual nifedipine, celiprolol alone, and then in association with nitroglycerin and nifedipine. Exercise tests were performed on a bicycle ergometer, with continuous electrocardiographic monitoring. Significantly more work was completed after treatment with celiprolol than at baseline (5280 +/- 2500 versus 4005 +/- 1792 kpm; P less than 0.01). There were further improvements in work completed after the addition of nitroglycerin and nifedipine. Celiprolol reduced the mean resting heart rate from a baseline value of 77.1 beats/min to 69.2 beats/min (P less than 0.01). In contrast, nifedipine induced tachycardia (82.6 beats/min). At rest, all treatments significantly reduced systolic blood pressure, but only nifedipine significantly reduced diastolic blood pressure. At the completion of the exercise protocol, celiprolol reduced the maximal systolic and diastolic blood pressure (P less than 0.05) with further decreases after the addition of nifedipine. The double product was significantly decreased by celiprolol compared with control, nitroglycerin and nifedipine. There was a further improvement of the double product after the addition of nitroglycerin to celiprolol, but the further increase after addition of nifedipine was not significant. In conclusion, it is clear that celiprolol, both alone and in combination with nitroglycerin or nifedipine, can significantly increase the work capacity of patients with exercise-induced angina pectoris and significantly reduce myocardial oxygen consumption.

[Contribution of Doppler echocardiography and thallium in cases of major ST segment depression in athletes]. / Apport de l'écho-Doppler et du thallium en cas de sous-décalage majeur chez le sportif.

False-positive responses to exercise tests have been reported as been more frequent in athletes than in the general population and attributed to physiological hypertrophy of the athlete's heart. In this study, we have investigated the significance of major ST depression (-3.55 +/- 1.8 mm) in a group of 13 athletes aged 40 +/- 9 years who had normal coronary angiography. All subjects underwent a standard exercise test followed by a second one after administration of nitroglycerin; the post-test probability of coronary was evaluated by multivariate analysis of the results. Myocardial perfusion was studied in 9 subjects by stress thallium 201 scintigraphy, and the data obtained were compared with those of angiography. Left ventricular hypertrophy was systematically looked for by calculating the myocardial mass index at echocardiography. The subjects were also investigated for possible alteration of the diastolic function, using doppler ultrasound. The mean follow-up period was 5 +/- 2 years. The mean performance at exercise tests was 238 +/- 118 watts. The Q wave significantly increased at exercise (-0.61 +/- 0.8; p less than 0.05), whereas the R wave remained constant (-0.95 +/- 4.5 mm; N.S.). The mean probability or coronary disease was 0.49 +/- 0.41, which justified the thallium scintigraphy test. This test was abnormal in 8 out of 9 cases. The myocardial mass index was slightly increased up to 138 +/- 25 g/m2, reflecting a very moderate physiological hypertrophy, as testified by the normality of diastolic function related to age in 8/9 cases. There was no obvious correlation between ST depression amplitude and myocardial mass index.(ABSTRACT TRUNCATED AT 250 WORDS)

Validation of a digitized Holter monitoring system by comparison with the Marquette case system.

Detection of silent myocardial ischaemia must be accurate and reliable. With the new digitized Holter monitoring systems these qualities are feasible. We tested one of these devices (Monitor One, Q Med) by comparison with a digitized and averaged ECG signal provided by the Marquette Case system during exercise tests in 30 patients with angiographically documented coronary artery disease. Detection and quantitation of ST segment depression episodes by the Holter system were excellent. Furthermore, indirect ECG criteria of ischaemia as R-wave amplitude variations were easily recognized. Thus digital monitors may be used to detect ischaemic events in prospective and multicentre studies for the diagnosis and prognosis of silent myocardial ischaemia.

[Echocardiographic diagnosis of aortic dissection. Limits, pitfalls and difficulties]. / Diagnostic échocardiographique des dissections aortiques. Limites, pièges et difficultés.

In patients with suspected dissection of the aorta two-dimensional echocardiography has become a fundamental complementary examination which can easily be used in emergencies. In the light of our experience and of published data, a floating dissected intima is the pathognomonic sign. However, false-negative results have been recorded in about 30% of the cases, as against 10% with angiography, computerized tomography and nuclear magnetic resonance imaging. In spite of this drawback, two-dimensional echocardiography still is a good screening examination, since dissection can almost certainly be excluded when the aorta is of normal caliber. False-positive results also constitute a diagnostic pitfall which must be well known and carefully avoided. The mechanisms of these various problems and the way they can be solved are discussed.

Nuclear waste: increasing scale and sociopolitical impacts.

The article argues that insufficient attention has been paid to the operational aspects of the U.S. radioactive waste management system when it grows to the scale necessary to handle wastes produced by a fully deployed plutonium economy. Without such information, many of the unsettling speculations which have become part of the public debate and are summarized herein cannot be clearly addressed. The article then outlines the types of information necessary to begin estimating the costs and consequences of radioactive waste management. Finally, an index of social exposure to radioactive hazard is proposed to improve the basis for policy decisions in this area.