A comparison of three DNA extractive procedures with Leptospira for polymerase chain reaction analysis

Three DNA extraction methods were evaluated in this study: proteinase K followed by phenol-chloroform; a plant proteinase (E6870) followed by phenol-chloroform; and boiling of leptospires in 0.1 mM Tris, pH 7.0 for 10 min at 100°C, with no phenol treatment. Every strain treated with proteinase K or E6870 afforded positive polymerase chain reaction (PCR) reaction. On the other hand, from five strains extracted by the boiling method, three did not feature the 849 bp band characteristic in Leptospira. We also evaluated by RAPD-PCR, DNAs from serovars isolated with proteinase K and proteinase 6870 with primers B11/B12. Each of the DNA samples provided PCR profiles in agreement with previous data. Moreover, the results with E6870 showed less background non-specific amplification, suggesting that removal of nucleases was more efficient with E6870. The limit for detection by PCR using Lep13/Lep14 was determined to be 10(2) leptospira, using the silver stain procedure.

Alcohol drinking and cardiovascular risk in a population with high mean alcohol consumption.

Moderate alcohol consumption has been associated with lower coronary artery disease (CAD) risk. However, data on the CAD risk associated with high alcohol consumption are conflicting. The aim of this study was to examine the impact of heavier drinking on 10-year CAD risk in a population with high mean alcohol consumption. In a population-based study of 5,769 adults (aged 35 to 75 years) without cardiovascular disease in Switzerland, 1-week alcohol consumption was categorized as 0, 1 to 6, 7 to 13, 14 to 20, 21 to 27, 28 to 34, and > or =35 drinks/week or as nondrinkers (0 drinks/week), moderate (1 to 13 drinks/week), high (14 to 34 drinks/week), and very high (> or =35 drinks/week). Blood pressure and lipids were measured, and 10-year CAD risk was calculated according to the Framingham risk score. Seventy-three percent (n = 4,214) of the participants consumed alcohol; 16% (n = 909) were high drinkers and 2% (n = 119) very high drinkers. In multivariate analysis, increasing alcohol consumption was associated with higher high-density lipoprotein cholesterol (from a mean +/- SE of 1.57 +/- 0.01 mmol/L in nondrinkers to 1.88 +/- 0.03 mmol/L in very high drinkers); triglycerides (1.17 +/- 1.01 to 1.32 +/- 1.05 mmol/L), and systolic and diastolic blood pressure (127.4 +/- 0.4 to 132.2 +/- 1.4 mm Hg and 78.7 +/- 0.3 to 81.7 +/- 0.9 mm Hg, respectively) (all p values for trend <0.001). Ten-year CAD risk increased from 4.31 +/- 0.10% to 4.90 +/- 0.37% (p = 0.03) with alcohol use, with a J-shaped relation. Increasing wine consumption was more related to high-density lipoprotein cholesterol levels, whereas beer and spirits were related to increased triglyceride levels. In conclusion, as measured by 10-year CAD risk, the protective effect of alcohol consumption disappears in very high drinkers, because the beneficial increase in high-density lipoprotein cholesterol is offset by the increases in blood pressure levels.

Attractiveness of black Shannon trap for phlebotomines

A white Shannon-type trap was used for captures of female sand flies in the search for natural infection with flagellates, however, due to its low productivity and as a large number of phlebotomines settled on the researchers' black clothes, we decided to compare the relative attractiveness of black and white Shannon-type traps for sand flies. Several pairs of black and white traps were placed side by side in front of caves in four areas in the Serra da Bodoquena, Bonito county, State of Mato Grosso do Sul, Brazil, for a total of 12 observations and 44 h of capture. The experiment resulted in 889 phlebotomines captured, 801 on the black and 88 on the white trap, representing 13 species. The hourly Williams' means were 8.67 and 1.24, respectively, and the black/white ratio was 7.0:1.0. Lutzomyia almerioi, an anthropophilic species closely associated with caves, was predominant (89%). Only two other species, Nyssomyia whitmani and Psathyromyia punctigeniculata, also anthropophilic, were significantly attracted to the black rather than to the white trap (chi2 test; p <= 0.01). The difference between the diversity index of the two traps was not significant at level 0.05. The black trap in these circumstances was much more productive than the white, especially for anthropophilic species.

L'hibernation du muscardin Muscardinus avellanarius (Gliridae, Rodentia) en nature: nids, fréquence de réveils et température corporelle

Six muscardins vivant en liberté, munis d'une marque radioactive, ont été étudiés durant un hiver dans leur habitat naturel. L'un d'eux était muni d'un radio-émetteur en position intrapéritonéale permettant de mesurer la température corporelle (Tc) au nid et sur des sites de nourrissage. Tous les nids d'hibernation (n=17) étaient situés sur le sol, dans la litière ou dans un gazon. Un nid d'été a été utilisé occasionnellement durant une période clémente. Entre décembre et avril, les périodes de torpeur de 2 à 27 jours (xmoy= 10.8 j). Les périodes de nomothérmie sans quitter le nid duraient 50 à 210 min (xmoy=105 min). Durant les réveils spontanés, la température corporelle était de 36.7 ± 0.4°C, correspondant à une température corporelle moyenne diurne durant le sommeil (36.8 ± 0.3°C). En captivité, la Tc durant la nuit équivalait à 37.6 ± 0.6°C , tandis que la température en activité, mesurée dans la nature, était de 38.5 ± 0.7°C. Durant la torpeur, la Tc était très proche de la température du sol (&#8710;T < 1°C); quand la température descendait à -3°, la Tc a été maintenue entre -0.4 et -0.8°C. Les nids d'hiver situés en surface du sol et sous une couverture de neige restent durant une grande partie de l'hibernation près de 0 ºC, ce qui est probablement proche de la température à laquelle M. avellanarius présente des dépenses énergétiques minimales.

Subclinical hypothyroidism and the risk of heart failure, other cardiovascular events, and death.

BACKGROUND: Subclinical hypothyroidism has been associated with systolic and diastolic cardiac dysfunction and an elevated cholesterol level, but data on cardiovascular outcomes and death are limited. METHODS: We studied 2730 men and women, aged 70 to 79 years, with baseline thyrotropin (TSH) measurements and 4-year follow-up data to determine whether subclinical hypothyroidism was associated with congestive heart failure (CHF), coronary heart disease, stroke, peripheral arterial disease, and cardiovascular-related and total mortality. After the exclusion of participants with abnormal thyroxine levels, subclinical hypothyroidism was defined as a TSH level of 4.5 mIU/L or greater, and was further classified according to TSH levels (4.5-6.9, 7.0-9.9, and &gt; or = 10.0 mIU/L). RESULTS: Subclinical hypothyroidism was present in 338 (12.4%) of the participants. Compared with euthyroid participants, CHF events occurred more frequently among those with a TSH level of 7.0 mIU/L or greater (35.0 vs 16.5 per 1000 person-years; P = .006), but not among those with TSH levels between 4.5 and 6.9 mIU/L. In multivariate analyses, the risk of CHF was higher among those with high TSH levels (TSH of 7.0-9.9 mIU/L: hazard ratio, 2.58 [95% confidence interval, 1.19-5.60]; and TSH of &gt; or = 10.0 mIU/L: hazard ratio, 3.26 [95% confidence interval, 1.37-7.77]). Among the 2555 participants without CHF at baseline, the hazard ratio for incident CHF events was 2.33 (95% confidence interval, 1.10-4.96; P = .03) in those with a TSH of 7.0 mIU/L or greater. Subclinical hypothyroidism was not associated with increased risk for coronary heart disease, stroke, peripheral arterial disease, or cardiovascular-related or total mortality. CONCLUSIONS: Subclinical hypothyroidism is associated with an increased risk of CHF among older adults with a TSH level of 7.0 mIU/L or greater, but not with other cardiovascular events and mortality. Further investigation is warranted to assess whether subclinical hypothyroidism causes or worsens preexisting heart failure.

Isochorismate synthase (PchA), the first and rate-limiting enzyme in salicylate biosynthesis of Pseudomonas aeruginosa.

In Pseudomonas aeruginosa the extracellular metabolite and siderophore pyochelin is synthesized from two major precursors, chorismate and l-cysteine via salicylate as an intermediate. The regulatory role of isochorismate synthase, the first enzyme in the pyochelin biosynthetic pathway, was studied. This enzyme is encoded by pchA, the last gene in the pchDCBA operon. The PchA protein was purified to apparent electrophoretic homogeneity from a PchA-overexpressing P. aeruginosa strain. The native enzyme was a 52-kDa monomer in solution, and its activity strictly depended on Mg(2+). At pH 7.0, the optimum, a K(m) = 4.5 microm and a k(cat) = 43.1 min(-1) were determined for chorismate. No feedback inhibitors or other allosteric effectors were found. The intracellular PchA concentration critically determined the rate of salicylate formation both in vitro and in vivo. In cultures grown in iron-limiting media to high cell densities, overexpression of the pchA gene resulted in overproduction of salicylate as well as in enhanced pyochelin formation. From this work and earlier studies, it is proposed that one important factor influencing the flux through the pyochelin biosynthetic pathway is the PchA concentration, which is determined at a transcriptional level, with pyochelin acting as a positive signal and iron as a negative signal.

Longitudinal Study on the Natural Infection of Biomphalaria straminea and B. glabrata by Schistosoma mansoni in an Endemic Area of Schistosomiasis in Pernambuco, Brazil

The abundance of snail hosts and the rates of infection with Schistosoma mansoni were monitored monthly for four years in two representative localities subjected to repeated chemotherapy of infected persons. Snail abundance varied from 1.0 to 4.4 collected per person/minute/station for Biomphalaria straminea and from 0.1 to 7.0 for B. glabrata. Infection rates of snails in nature varied from 0% to 15% for the former and from 0% to 70% for the latter species. Human infection increased from 35.5% to 61.9% in the locality occupied by B. straminea, and decreased from 40.3% to 20.8% in that occupied by B. glabrata. No relationship could be detected between human infection and the snail variables. Despite seasonal variations, natural infection persisted throughout the monitoring period in both snail species. It reached remarkably high levels in B. straminea when compared to those obtained by other authors probably because of differences in methodology. It is recommended that longitudinal studies should be carried out focally and periodically to avoid underestimating the prevalence of schistosome infection in snails.

Biometal muscle to restore atrial transport function in a permanent atrial fibrillation animal model: a potential tool in the treatment of end-stage heart failure.

BACKGROUND: Half of the patients with end-stage heart failure suffer from persistent atrial fibrillation (AF). Atrial kick (AK) accounts for 10-15% of the ejection fraction. A device restoring AK should significantly improve cardiac output (CO) and possibly delay ventricular assist device (VAD) implantation. This study has been designed to assess the mechanical effects of a motorless pump on the right chambers of the heart in an animal model. METHODS: Atripump is a dome-shaped biometal actuator electrically driven by a pacemaker-like control unit. In eight sheep, the device was sutured onto the right atrium (RA). AF was simulated with rapid atrial pacing. RA ejection fraction (EF) was assessed with intracardiac ultrasound (ICUS) in baseline, AF and assisted-AF status. In two animals, the pump was left in place for 4 weeks and then explanted. Histology examination was carried out. The mean values for single measurement per animal with +/-SD were analysed. RESULTS: The contraction rate of the device was 60 per min. RA EF was 41% in baseline, 7% in AF and 21% in assisted-AF conditions. CO was 7+/-0.5 l min(-1) in baseline, 6.2+/-0.5 l min(-1) in AF and 6.7+/-0.5 l min(-1) in assisted-AF status (p&lt;0.01). Histology of the atrium in the chronic group showed chronic tissue inflammation and no sign of tissue necrosis. CONCLUSIONS: The artificial muscle restores the AK and improves CO. In patients with end-stage cardiac failure and permanent AF, if implanted on both sides, it would improve CO and possibly delay or even avoid complex surgical treatment such as VAD implantation.

Exposure to tobacco smoke before and after a partial smoking ban in prison: indoors air quality measures

Although exposure to secondhand smoke (SHS) is reportedly high in prison, few studies have measured this in the prison environment, and none have done so in Europe. We measured two indicators of SHS exposure (particulate matter PM10 and nicotine) in fixed locations before (2009) and after (2010) introduction of a partial smoking ban in a Swiss prison. Access to smoking cessation support was available to detainees throughout the study. Objectives To measure SHS before and after the introduction of a partial smoking ban. Methods Assessment of particulate matter PM10 (suspended microparticles of 10&#8197;&#956;m) and nicotine in ambient air, collected by real-time aerosol monitor and nicotine monitoring devices. Results The authors observed a significant improvement of nicotine concentrations in the air after the introduction of the smoking ban (before: 7.0&#8197;&#956;g/m(3), after: 2.1&#8197;&#956;g/m(3), difference 4.9&#8197;&#956;g/m(3), 95% CI for difference: 0.52 to 9.8, p=0.03) but not in particulate matter PM10 (before: 0.11&#8197;mg/m(3), after: 0.06&#8197;mg/m(3), difference 0.06 mg/m(3), 95% CI for difference of means: -0.07 to 0.19, p=0.30). Conclusions The partial smoking ban was followed by a decrease in nicotine concentrations in ambient air. These improvements can be attributed to the introduction of the smoking ban since no other policy change occurred during this period. Although this shows that concentrations of SHS decreased significantly, protection was still incomplete and further action is necessary to improve indoor air quality.

Oxygen uptake during early cardiogenesis of the chick.

Oxidative metabolism of the isolated embryonic heart of the chick has been determined using a spectrophotometric technique allowing global as well as localized micromeasurements of the O2 uptake. Entire hearts, excised from embryos of 10 somites (primordia fused, stage 10 HH) and 40 somites (S shaped, stage 20 HH) were placed in a special chamber under controlled metabolic conditions where they continued to beat spontaneously and regularly. During the 32 h of development, the O2 consumption of the whole heart increased from 0.9 +/- 0.1 to 5.3 +/- 0.8 nmol O2/h. These values corrected for protein content were, however, comparable (0.45 nmol O2.h-1.micrograms-1). At stage 10-12, the O2 uptake varied along the cardiac tube (from 0.74 to 1.0 nmol O2.h-1.mm-2). From stage 10 to 20, the O2 uptake per unit area of ventricle wall increased from 0.7 +/- 0.2 to 1.8 +/- 0.2 nmol O2.h-1.mm-2, and the O2 uptake per myocardial volume during one cardiac cycle varied from 7 to 2.5 nmol O2/cm3. These results indicate that, despite an intense morphogenesis, the cardiac tissue has a rather low and stable oxidative metabolism, although the O2 requirement of the whole heart increases significantly. Moreover, the normalized suprabasal aerobic energy expenditure decreases throughout early cardiogenesis. The functional integrity of the isolated embryonic heart combined with the experimental possibilities of the microtechnique make the preparation appropriate for studying the changes in cardiac metabolism during development.

Gender difference in the response to an angiotensin-converting enzyme inhibitor and a diurectic in hypertensive patients of African descent

Résumé de la thèse en français Titre : Différence entre hommes et femmes dans la réponse à un inhibiteur de l'enzyme de conversion de l'angiotensine et un diurétique chez des patients hypertendus d'origine Africaine. Introduction: L'efficacité des inhibiteurs de l'enzyme de conversion de l'angiotensine (ACEI) dans le traitement de l'hypertension artérielle chez les patients africains est controversée. Objectif: Nous avons examiné la baisse de la tension artérielle ambulatoire (ABP) en réponse à un diurétique et un ACEI chez des patients hypertendus d'origine africaine et nous avons évalué les différentes caractéristiques déterminant l'efficacité du traitement. Méthodes: Etude en simple-aveugle randomisée, en crossover AB/BA. Arrangement Familles hypertendues d'origine africaine de la population générale des Seychelles. Participants : 52 patients (29 hommes et 23 femmes) sur 62 patients hypertendus éligibles ont été inclus. Le principal résultat était la mesure de la réponse de l'ABP à 20 mg de lisinopril (LIS) ou 25 mg d'hydrochlorothiazide (HCT) quotidiennement pendant quatre semaines. Résultats: Le jour, la réponse systolique/diastolique de l'ABP sous HCT était de 4.9 (95% intervalle de confiance (IC) 1.2-8.6)/3.6 (1.0-6.2) mm Hg pour les hommes et 12.9 (9.216.6)/6.3 (3.7-8.8) mm Hg pour les femmes. Sous LIS, la réponse était de 18.8 (15.022.5)/14.6 (12.0-17.1) mm Hg pour les hommes et de 12.4 (8.7-16.2)/7.7 (5.1-10.2) mm Hg pour les femmes. La nuit, la réponse systolique/diastolique sous HCT était de 5.0 (0.6-9.4)/2.7 ((-0.4)-5.7) mm Hg pour les hommes et de 11.5 (7.1-16.0)/5.7 (2.6-8.8) mm Hg pour les femmes, et sous LIS était de 18.7 (14.2-22.1)/15.4 (12.4-18.5) mm Hg pour les hommes et de 3.5 ((-1.0)-7.9)/2.3 ((-0.8)-5.4) mm Hg pour les femmes. L'analyse de régression linéaire multiple a montré que le sexe est un prédicteur indépendant de la réponse tensionnelle à l'HCT et au LIS. Conclusions : Les patients hypertendus d'origine africaine ont présenté une baisse tensionnelle plus grande en réponse au LIS qu'à l'HCT. Les hommes ont mieux répondu au LIS qu'à l'HCT alors que les femmes ont répondu de manière similaire aux deux traitements.

Is the GraftConnector a valid alternative to running suture in end-to-side coronary arteries anastomoses?

BACKGROUND: An animal study was carried out to compare long-term patency rates of coronary anastomoses performed with the GraftConnector versus running suture technique. METHODS: 10 sheep, 45 to 55 kg, underwent off-pump coronary artery bypass grafting (right internal mammary artery to left anterior descending artery). In 5 animals, the anastomosis was performed with a GraftConnector and in 5 animals with 7-0 running suture. Intraoperative fluoroscopy and a fluoroscopic control at 6 months were performed. After 6 months, the animals were sacrificed and the anastomoses were examined histologically. RESULTS: All animals survived at 6 months with 100% anastomosis patency rates in both groups. In the GraftConnector group, the anastomosis diameter at 6 months fluoroscopy was 118% of native left anterior descending artery versus 97% of the control group. Luminal anastomotic width at histology was 1.7 +/- 0.2 mm in the device group versus 1.6 +/- 0.1 mm in the control group. Mean intimal hyperplasia thickness was 0.21 +/- 0.1 mm in the device group versus 0.01 mm in the control group. CONCLUSIONS: The GraftConnector provides a consistent and reproducible coronary artery anastomosis and reduces technical demand and manual dexterity in coronary operations. Long-term results demonstrate that off-pump coronary artery bypass grafting performed with the GraftConnector had the same patency rate and luminal width as those performed with running suture.

Five Years Of Denosumab Treatment In Women With Postmenopausal Osteoporosis: Preliminary Results From The Freedom Extension Study

Aims: The pivotal FREEDOM study evaluated the effi cacy and safety of 3 years' denosumab treatment in women with postmenopausal osteoporosis (PMO).1 Since osteoporosis is a chronic condition requiring long-term therapy, FREEDOM was extended to further elucidate the safety and effi cacy of long-term denosumab administration. We present data from the fi rst 2 years of this extension, representing up to 5 years' continuous exposure to denosumab.Methods: Patients who completed FREEDOM were eligible for the extension. Women continued to receive (long-term group), or started after 3 years' placebo (cross-over group), denosumab 60 mg sc every 6 months and daily calcium and vitamin D. These data refl ect 5 years' (long-term) or 2 years' (cross-over) continuous denosumab treatment. Effi cacy measures include changes in BMD from extension study baseline and bone turnover markers (BTM). P-values are descriptive.Results: Of the 83.0% of subjects who completed FREEDOM, 70.2% (N = 4550) agreed to participate in the extension (long-term: 2343; cross-over: 2207). In the long-term group, there were further signifi cant gains (P &lt; 0.0001) in BMD in years 4 and 5: 1.9% and 1.7% at the lumbar spine to a total of 13.7% from FREEDOM baseline and 0.7% and 0.6% at the total hip to a total of 7.0%. During their fi rst 2 years' denosumab treatment, women in the cross-over group had signifi cant improvements in lumbar spine (7.9%) and total hip BMD (4.1%) (P &lt; 0.0001). Serum C-telopeptide (CTX) was rapidly reduced following denosumab dosing in both groups, with the characteristic attenuation of CTX reduction observed at the end of the dosing interval. A low incidence of new vertebral and nonvertebral fractures was reported for both groups. The denosumab safety profi le did not change over time.Conclusions: Denosumab treatment for up to 5 years in women with PMO remains well tolerated, maintains reduction of BTMs and continues to significantly increase BMD.Reference1. Cummings. NEJM 2009;361:756.

Effect of malaria and fever on energy metabolism in Gambian children.

The aim of the present study was to measure the changes in resting energy expenditure (REE) induced by malaria and to assess to what extent they are related to fever and nutritional status. The REE of 19 Gambian children (mean age +/- SEM, 9 +/- 1 y; weight, 24 +/- 2 kg; expected weight for height 86 +/- 1%) were measured with a hood system at repeated intervals at the onset of malaria crisis (test A), 3 to 4 d after therapy (test B), and 14 to 21 d later (test C). Axillary temperature averaged 39.2 +/- 0.1, 36.6 +/- 0.1, and 36.7 +/- 0.1 degrees C in the tests A, B, and C, respectively. REE in test A was significantly higher than REE in test B (223 +/- 10 versus 174 +/- 8 kJ/kg.d, p less than 0.0001), but in test C (169 +/- 8 kJ/kg.d), it did not differ from that observed in test B. The percentage of increase in REE was significantly correlated with the difference in axillary temperature (r = 0.46, p less than 0.05); the slope of the regression line indicated an increase of 6.9% in REE/degree C of fever. Furthermore, the individual increase in REE/degree C was correlated to the percentage of weight for height of the children (r = 0.54, p less than 0.05), indicating that the child's nutritional status influences the magnitude of the hypermetabolism due to fever. We concluded that Gambian children suffering from an acute episode of malaria have an increase in REE averaging 30%; however, REE promptly returns to baseline value a few days after the beginning of therapy.

A simple way to decompress the left ventricle during venoarterial bypass

OBJECTIVE: The aim of this investigation was to improve the hemodynamics during venoarterial bypass by remote decompression of the left ventricle (LV). METHODS: Venoarterial bypass was established in 5 bovine experiments (69+/-10 kg) by the transjugular insertion of a self-expanding cannula (smartcanula) with return through a carotid artery. Cardiogenic shock was simulated with ventricular fibrillation induced by an external stimulator. Left ventricular decompression was achieved by switching to transfemoral drainage of the pulmonary artery (PA) with a long self-expanding cannula. RESULTS: Initial pump flow was 4.7+/-0.9 l/min and the aortic pressure accounted for 75+/-21 mmHg. After induction of ventricular fibrillation, the pump flow dropped after 11+/-8 min to 2.5+/-0.1 l/min. Transfemoral decompression increased the pump flow to 5.6+/-0.7 l/min, while the RV pressure decreased from 27+/-9 to 3+/-5 mmHg, the PA pressure decreased from 29+/-7 to 5+/-4 mmHg, the LV pressure decreased from 29+/-6 to 7+/-2 mmHg, and the aortic pressure increased from 31+/-3 to 47+/-11 mmHg. CONCLUSIONS: Remote drainage of the pulmonary artery during venoarterial bypass allows for effective decompression of the left ventricle and provides superior hemodynamics.