8 resultados para Two-body correlation
em Université de Lausanne, Switzerland
Resumo:
BackgroundThe great diversity of bat haemosporidians is being uncovered with the help of molecular tools. Yet most of these studies provide only snapshots in time of the parasites discovered. Polychromophilus murinus, a malaria-like blood parasite, specialised on temperate-zone bats is a species that is being `rediscovered¿. This study describes the infection dynamics over time and between host sex and age classes.MethodsFor three years we followed the members of three breeding colonies of Myotis daubentonii in Western Switzerland and screened them for the prevalence and parasitemia of P. murinus using both molecular tools and traditional microscopy. In order to identify more susceptible classes of hosts, we measured, sexed and aged all individuals. During one year, we additionally measured body temperature and haematocrit values.ResultsJuvenile bats demonstrated much higher parasitemia than any other age class sampled, suggesting that first exposure to the parasite is very early in life during which infections are also at their most intense. Moreover, in subadults there was a clear negative correlation between body condition and intensity of infection, whereas a weak positive correlation was observed in adults. Neither body temperature, nor haematocrit, two proxies used for pathology, could be linked to intensities of infection.ConclusionIf both weaker condition and younger age are associated with higher infection intensity, then the highest selection pressure exerted by P. murinus should be at the juvenile stage. Confusion over the identities and nomenclature of malarial-like parasites requires that molecular barcodes are coupled to accurate morphological descriptions.
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OBJECTIVE: Contemporary free-breathing non contrast enhanced cardiovascular magnetic resonance angiography (CMRA) was qualitatively and quantitatively evaluated to ascertain the reproducibility of the method for coronary artery luminal dimension measurements. SUBJECTS AND METHODS: Twenty-two healthy volunteers (mean age 32 +/- 7 years, 12 males) without coronary artery disease were imaged at 2 centers (1 each in Europe and North America) using navigator-gated and corrected SSFP CMRA on a commercial whole body 1.5T System. Repeat images of right (RCA, n = 21), left anterior descending (LAD, n = 14) and left circumflex (LCX, n = 14) coronary arteries were obtained in separate sessions using identical scan protocol and imaging parameters. True visible vessel length, signal-to-noise (SNR), contrast-to-noise ratios (CNR) and the average luminal diameter over the first 4 cm of the vessel were measured. Intra-observer, inter-observer and inter-scan reproducibility of coronary artery luminal diameter were determined using Pearson's correlation, Bland-Altman analysis and intraclass correlation coefficients (ICC). RESULTS: CNR, SNR and the mean length of the RCA, LAD and LCX imaged for original and repeat scans were not significantly different (all p > 0.30). There was a high degree of intra-observer, inter-observer and inter-scan agreements for RCA, LAD and LCX luminal diameter respectively on Bland-Altman and ICC analysis (ICC's for RCA: 0.98. 0.98 and 0.86; LAD: 0.89, 0.89 and 0.63; LCX: 0.95, 0.94 and 0.79). CONCLUSION: In a 2-center study, we demonstrate that free-breathing 3D SSFP CMRA can visualize long continuous segments of coronary vessels with highly reproducible measurements of luminal diameter.
Resumo:
AIM: To assess the role of Helicobacter pylori (H. pylori), gastroesophageal reflux disease (GERD), age, smoking and body weight on the development of intestinal metaplasia of the gastric cardia (IMC).¦METHODS: Two hundred and seventeen patients scheduled for esophagogastroduodenoscopy were enrolled in this study. Endoscopic biopsies from the esophagus, gastroesophageal junction and stomach were evaluated for inflammation, the presence of H. pylori and intestinal metaplasia. The correlation of these factors with the presence of IMC was assessed using logistic regression.¦RESULTS: IMC was observed in 42% of the patients. Patient age, smoking habit and body mass index (BMI) were found as potential contributors to IMC. The risk of developing IMC can be predicted in theory by combining these factors according to the following formula: Risk of IMC = a + s - 2B where a = 2,...6 decade of age, s = 0 for non-smokers or ex-smokers, 1 for < 10 cigarettes/d, 2 for > 10 cigarettes/d and B = 0 for BMI < 25 kg/m² (BMI < 27 kg/m² in females), 1 for BMI > 25 kg/m² (BMI > 27 kg/m² in females). Among potential factors associated with IMC, H. pylori had borderline significance (P = 0.07), while GERD showed no significance.¦CONCLUSION: Age, smoking and BMI are potential factors associated with IMC, while H. pylori and GERD show no significant association. IMC can be predicted in theory by logistic regression analysis.
Resumo:
OBJECTIVE: Lipids stored in adipose tissue can originate from dietary lipids or from de novo lipogenesis (DNL) from carbohydrates. Whether DNL is abnormal in adipose tissue of overweight individuals remains unknown. The present study was undertaken to assess the effect of carbohydrate overfeeding on glucose-induced whole body DNL and adipose tissue lipogenic gene expression in lean and overweight humans. DESIGN: Prospective, cross-over study. SUBJECTS AND METHODS: A total of 11 lean (five male, six female, mean BMI 21.0+/-0.5 kg/m(2)) and eight overweight (four males, four females, mean BMI 30.1+/-0.6 kg/m(2)) volunteers were studied on two occasions. On one occasion, they received an isoenergetic diet containing 50% carbohydrate for 4 days prior to testing; on the other, they received a hyperenergetic diet (175% energy requirements) containing 71% carbohydrates. After each period of 4 days of controlled diet, they were studied over 6 h after having received 3.25 g glucose/kg fat free mass. Whole body glucose oxidation and net DNL were monitored by means of indirect calorimetry. An adipose tissue biopsy was obtained at the end of this 6-h period and the levels of SREBP-1c, acetyl CoA carboxylase, and fatty acid synthase mRNA were measured by real-time PCR. RESULTS: After isocaloric feeding, whole body net DNL amounted to 35+/-9 mg/kg fat free mass/5 h in lean subjects and to 49+/-3 mg/kg fat free mass/5 h in overweight subjects over the 5 h following glucose ingestion. These figures increased (P<0.001) to 156+/-21 mg/kg fat free mass/5 h in lean and 64+/-11 mg/kg fat free mass/5 h (P<0.05 vs lean) in overweight subjects after carbohydrate overfeeding. Whole body DNL after overfeeding was lower (P<0.001) and glycogen synthesis was higher (P<0.001) in overweight than in normal subjects. Adipose tissue SREBP-1c mRNA increased by 25% in overweight and by 43% in lean subjects (P<0.05) after carbohydrate overfeeding, whereas fatty acid synthase mRNA increased by 66 and 84% (P<0.05). CONCLUSION: Whole body net DNL is not increased during carbohydrate overfeeding in overweight individuals. Stimulation of adipose lipogenic enzymes is also not higher in overweight subjects. Carbohydrate overfeeding does not stimulate whole body net DNL nor expression of lipogenic enzymes in adipose tissue to a larger extent in overweight than lean subjects.
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OBJECTIVE: Both subclinical hypothyroidism and the metabolic syndrome have been associated with increased risk of coronary heart disease events. It is unknown whether the prevalence and incidence of metabolic syndrome is higher as TSH levels increase, or in individuals with subclinical hypothyroidism. We sought to determine the association between thyroid function and the prevalence and incidence of the metabolic syndrome in a cohort of older adults. DESIGN: Data were analysed from the Health, Ageing and Body Composition Study, a prospective cohort of 3075 community-dwelling US adults. PARTICIPANTS: Two thousand one hundred and nineteen participants with measured TSH and data on metabolic syndrome components were included in the analysis. MEASUREMENTS: TSH was measured by immunoassay. Metabolic syndrome was defined per revised ATP III criteria. RESULTS: At baseline, 684 participants met criteria for metabolic syndrome. At 6-year follow-up, incident metabolic syndrome developed in 239 individuals. In fully adjusted models, each unit increase in TSH was associated with a 3% increase in the odds of prevalent metabolic syndrome (OR, 1.03; 95% CI, 1.01-1.06; P = 0.02), and the association was stronger for TSH within the normal range (OR, 1.16; 95% CI, 1.03-1.30; P = 0.02). Subclinical hypothyroidism with a TSH > 10 mIU/l was significantly associated with increased odds of prevalent metabolic syndrome (OR, 2.3; 95% CI, 1.0-5.0; P = 0.04); the odds of incident MetS was similar (OR 2.2), but the confidence interval was wide (0.6-7.5). CONCLUSIONS: Higher TSH levels and subclinical hypothyroidism with a TSH > 10 mIU/l are associated with increased odds of prevalent but not incident metabolic syndrome.
Resumo:
Over the last two decades, several genes have been identified that appear to play a role in the regulation of energy homeostasis and body weight. For a small subset of them, a reduction or an absence of expression confers a resistance to the development of obesity. Recently, a knockin mouse for a member of the monocarboxylate transporter (MCT) family, MCT1, was demonstrated to exhibit a typical phenotype of resistance to diet-induced obesity and a protection from its associated metabolic perturbations. Such findings point out at MCTs as putatively new therapeutic targets in the context of obesity. Here, we will review what is known about MCTs and their possible metabolic roles in different organs and tissues. Based on the description of the phenotype of the MCT1 knockin mouse, we will also provide some insights about their putative roles in weight gain regulation.
Resumo:
Common variants at only two loci, FTO and MC4R, have been reproducibly associated with body mass index (BMI) in humans. To identify additional loci, we conducted meta-analysis of 15 genome-wide association studies for BMI (n > 32,000) and followed up top signals in 14 additional cohorts (n > 59,000). We strongly confirm FTO and MC4R and identify six additional loci (P < 5 x 10(-8)): TMEM18, KCTD15, GNPDA2, SH2B1, MTCH2 and NEGR1 (where a 45-kb deletion polymorphism is a candidate causal variant). Several of the likely causal genes are highly expressed or known to act in the central nervous system (CNS), emphasizing, as in rare monogenic forms of obesity, the role of the CNS in predisposition to obesity.
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The costs related to the treatment of infected total joint arthroplasties represent an ever groving burden to the society. Different patient-adapted therapeutic options like débridement and retention, 1- or 2-step exchange can be used. If a 2-step exchange is used we have to consider short (2-4 weeks) or long (>4-6 weeks) interval treatment. The Swiss DRG (Diagnose related Groups) determines the reimboursement the hopsital receives for the treatment of an infected total arthroplasty. The review assesses the cost-effectiveness of hospitalisation practices linked to surgical treatment in the two-stage exchange of a prosthetic-joint infection. The aim of this retrospectiv study is to compare the economical impact between a short (2 to 4 weeks) versus a long (6 weeks and above) interval during a two-satge procedure to determine the financial impact. Retrospectiv study of the patients with a two-stage procedure for a hip or knee prosthetic joint infection at CHUV hospital Lausanne (Switzerland) between 2012 and 2013. The review analyses the correlation between the interval length and the length of the hospital stay as well as with the costs and revenues per hospital stay. In average there is a loss of 40′000 Euro per hospitalisation for the treatment of prosthetic joint infection. Revenues never cover all the costs, even with a short interval procedure. This economical loss increases with the length of the hospital stay if a long-term intervall is choosen. The review explores potential for improvement in reimbourement practices and hospitalisation practices in the current Swiss healthcare setting. There should be alternative setups to decrease the burden of medical costs by a) increase the reimboursment for the treatment of infected total joints or by b) splitting the hospital stay with partners (rapid transfer after first operation from center hospital to level 2 hospital and retransfer for second operation to center) in order to increase revenues.