960 resultados para Parametric and semiparametric methods


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Coagulase-negative staphylococci (CNS) species identification is still difficult for most clinical laboratories. The scheme proposed by Kloos and Schleifer and modified by Bannerman is the reference method used for the identification of staphylococcal species and subspecies; however, this method is relatively laborious for routine use since it requires the utilization of a large number of biochemical tests. The objective of the present study was to compare four methods, i.e., the reference method, the API Staph system (bioMérieux) and two methods modified from the reference method in our laboratory (simplified method and disk method), in the identification of 100 CNS strains. Compared to the reference method, the simplified method and disk method correctly identified 100 and 99% of the CNS species, respectively, while this rate was 84% for the API Staph system. Inaccurate identification by the API Staph method was observed for Staphylococcus epidermidis (2.2%), S. hominis (25%), S. haemolyticus (37.5%), and S. warneri (47.1%). The simplified method using the simple identification scheme proposed in the present study was found to be efficient for all strains tested, with 100% sensitivity and specificity and proved to be available alternative for the identification of staphylococci, offering, higher reliability and lower cost than the currently available commercial systems. This method would be very useful in clinical microbiology laboratory, especially in places with limited resources.

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This work has highlighted a number of areas of prescribing concern, for example, the long term use of both benzodiazepines and hypnotics, in older residents residing in long term care facilities. Each of these individual areas should be further investigated to determine the underlying reason(s) for the prescribing concerns in these areas and strategic methods of addressing and preventing further issues should be developed on a national level.This resource was contributed by The National Documentation Centre on Drug Use.

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BACKGROUND: This study reviews the 15 year program of our Department of Pediatric Surgery for the treatment and follow-up of children born with a cleft in Benin and Togo. METHODS: We analyzed files of children born in Africa with a cleft. They were referred to us through a nongovernmental organization (NGO) between 1993 and 2008 and assessed in Africa by local pediatricians before and after surgery. Operations were performed by our team. RESULTS: Two hundred files were reviewed: 60 cases of unilateral cleft lip, seven of bilateral cleft lip, 44 of unilateral cleft lip palate (UCLP), 29 of bilateral cleft lip palate (BCLP), 53 of cleft palate (CP), three of bilateral oro-ocular cleft, one of unilateral and two of median clefts (Binder), and one of commissural cleft. Sixty-nine (35 %) of these cases were not operated in Africa: 25 (12.5 %) had not shown up, 28 (15 %) were considered unfit for surgery (Down's syndrome, HIV-positive, malnutrition, cardiac malformation), and 16 (7.5 %) were transferred to Switzerland. Palatal fistula occurred in 20 % of UCLP, 30 % of BCLP, and 16 % of CP. Evaluation of speech after palate surgery gave less than 50 % of socially acceptable speech. CONCLUSIONS: Our partnership with a NGO and a local team makes it possible to treat and subsequently follow children born with a cleft in West Africa. Surgery is performed under good conditions. If aesthetic results are a success, functional results after palate surgery need further improvement to promote integration in school and social life.

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Purpose: To report the magnetic resonance imaging (MRI) findings in athletic injuries of the extensor carpi ulnaris (ECU) subsheath, assessing the utility of gadolinium-enhanced (Gd) fat-saturated (FS) T1-weighted sequences with wrist pronation and supination. Methods and Materials: Sixteen patients (13 males, 3 females; mean age 30.3 years) with athletic injuries of the ECU subsheath sustained between January 2003 and June 2009 were included in this retrospective study. Initial and follow‑up 1.5-T wrist MRIs were performed with transverse T1-weighted and STIR sequences in pronation, and Gd FS T1-weighted sequences with wrist pronation and supination. Two radiologists assessed the type of injury (A to C), ECU tendon stability, associated lesions and rated pulse sequences using a three-point scale: 1 = poor, 2 = good and 3 = excellent. Results: Gd-enhanced FS T1-weighted transverse sequences in supination (2.63) and pronation (2.56) were most valuable, compared with STIR (2.19) and T1 weighted (1.94). Nine type A, one type B and six type C injuries were found. There were trends towards diminution in size, signal intensity and enhancement of associated pouches on follow‑up MRI and tendon stabilisation within the ulnar groove. Conclusion: Gd-enhanced FS T1-weighted sequences with wrist pronation and supination are most valuable in assessing and follow‑up athletic injuries of the ECU subsheath on 1.5-T MRI.

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BACKGROUND: Data for trends in glycaemia and diabetes prevalence are needed to understand the effects of diet and lifestyle within populations, assess the performance of interventions, and plan health services. No consistent and comparable global analysis of trends has been done. We estimated trends and their uncertainties in mean fasting plasma glucose (FPG) and diabetes prevalence for adults aged 25 years and older in 199 countries and territories. METHODS: We obtained data from health examination surveys and epidemiological studies (370 country-years and 2·7 million participants). We converted systematically between different glycaemic metrics. For each sex, we used a Bayesian hierarchical model to estimate mean FPG and its uncertainty by age, country, and year, accounting for whether a study was nationally, subnationally, or community representative. FINDINGS: In 2008, global age-standardised mean FPG was 5·50 mmol/L (95% uncertainty interval 5·37-5·63) for men and 5·42 mmol/L (5·29-5·54) for women, having risen by 0·07 mmol/L and 0·09 mmol/L per decade, respectively. Age-standardised adult diabetes prevalence was 9·8% (8·6-11·2) in men and 9·2% (8·0-10·5) in women in 2008, up from 8·3% (6·5-10·4) and 7·5% (5·8-9·6) in 1980. The number of people with diabetes increased from 153 (127-182) million in 1980, to 347 (314-382) million in 2008. We recorded almost no change in mean FPG in east and southeast Asia and central and eastern Europe. Oceania had the largest rise, and the highest mean FPG (6·09 mmol/L, 5·73-6·49 for men; 6·08 mmol/L, 5·72-6·46 for women) and diabetes prevalence (15·5%, 11·6-20·1 for men; and 15·9%, 12·1-20·5 for women) in 2008. Mean FPG and diabetes prevalence in 2008 were also high in south Asia, Latin America and the Caribbean, and central Asia, north Africa, and the Middle East. Mean FPG in 2008 was lowest in sub-Saharan Africa, east and southeast Asia, and high-income Asia-Pacific. In high-income subregions, western Europe had the smallest rise, 0·07 mmol/L per decade for men and 0·03 mmol/L per decade for women; North America had the largest rise, 0·18 mmol/L per decade for men and 0·14 mmol/L per decade for women. INTERPRETATION: Glycaemia and diabetes are rising globally, driven both by population growth and ageing and by increasing age-specific prevalences. Effective preventive interventions are needed, and health systems should prepare to detect and manage diabetes and its sequelae. FUNDING: Bill & Melinda Gates Foundation and WHO.

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The number of physical activity measures and indexes used in the human literature is large and may result in some difficulty for the average investigator to choose the most appropriate measure. Accordingly, this review is intended to provide information on the utility and limitations of the various measures. Its primary focus is the objective assessment of free-living physical activity in humans based on physiological and biomechanical methods. The physical activity measures have been classified into three categories: Measures based on energy expenditure or oxygen uptake, such as activity energy expenditure, activity-related time equivalent, physical activity level, physical activity ratio, metabolic equivalent, and a new index of potential interest, daytime physical activity level. Measures based on heart rate monitoring, such as net heart rate, physical activity ratio heart rate, physical activity level heart rate, activity-related time equivalent, and daytime physical activity level heart rate. Measures based on whole-body accelerometry (counts/U time). Quantification of the velocity and duration of displacement in outdoor conditions by satellites using the Differential Global Positioning System may constitute a surrogate for physical activity, because walking is the primary activity of man in free-living conditions. A general outline of the measures and indexes described above is presented in tabular form, along with their respective definition, usual applications, advantages, and shortcomings. A practical example is given with typical values in obese and non-obese subjects. The various factors to be considered in the selection of physical activity methods include experimental goals, sample size, budget, cultural and social/environmental factors, physical burden for the subject, and statistical factors, such as accuracy and precision. It is concluded that no single current technique is able to quantify all aspects of physical activity under free-living conditions, requiring the use of complementary methods. In the future, physical activity sensors, which are of low-cost, small-sized, and convenient for subjects, investigators, and clinicians, are needed to reliably monitor, during extended periods in free-living situations, small changes in movements and grade as well as duration and intensity of typical physical activities.

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OBJECTIVE: To examine the relationship between reward sensitivity and self-reported apathy in stroke patients and to investigate the neuroanatomical correlates of both reward sensitivity and apathy. METHODS: In this prospective study, 55 chronic stroke patients were administered a questionnaire to assess apathy and a laboratory task to examine reward sensitivity by measuring motivationally driven behavior ("reinforcement-related speeding"). Fifteen participants without brain damage served as controls for the laboratory task. Negative mood, working memory, and global cognitive functioning were also measured to determine whether reward insensitivity and apathy were secondary to cognitive impairments or negative mood. Voxel-based lesion-symptom mapping was used to explore the neuroanatomical substrates of reward sensitivity and apathy. RESULTS: Participants showed reinforcement-related speeding in the highly reinforced condition of the laboratory task. However, this effect was significant for the controls only. For patients, poorer reward sensitivity was associated with greater self-reported apathy (p < 0.05) beyond negative mood and after lesion size was controlled for. Neither apathy nor reward sensitivity was related to working memory or global cognitive functioning. Voxel-based lesion-symptom mapping showed that damage to the ventral putamen and globus pallidus, dorsal thalamus, and left insula and prefrontal cortex was associated with poorer reward sensitivity. The putamen and thalamus were also involved in self-reported apathy. CONCLUSIONS: Poor reward sensitivity in stroke patients with damage to the ventral basal ganglia, dorsal thalamus, insula, or prefrontal cortex constitutes a core feature of apathy. These results provide valuable insight into the neural mechanisms and brain substrate underlying apathy.

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OBJECTIVE: A large body of epidemiologic data strongly suggests an association between excess adiposity and coronary artery disease (CAD). Low adiponectin levels, a hormone secreted only from adipocytes, have been associated with an increased risk of CAD in observational studies. However, these associations cannot clarify whether this relationship is causal or due to a shared set of causal factors or even confounding. Genome-wide association studies have identified common variants that influence adiponectin levels, providing valuable tools to examine the genetic relationship between adiponectin and CAD. METHODS: Using 145 genome wide significant SNPs for adiponectin from the ADIPOGen consortium (n = 49,891), we tested whether adiponectin-decreasing alleles influenced risk of CAD in the CARDIoGRAM consortium (n = 85,274). RESULTS: In single-SNP analysis, 5 variants among 145 SNPs were associated with increased risk of CAD after correcting for multiple testing (P < 4.4 × 10(-4)). Using a multi-SNP genotypic risk score to test whether adiponectin levels and CAD have a shared genetic etiology, we found that adiponectin-decreasing alleles increased risk of CAD (P = 5.4 × 10(-7)). CONCLUSION: These findings demonstrate that adiponectin levels and CAD have a shared allelic architecture and provide rationale to undertake a Mendelian randomization studies to understand if this relationship is causal.

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Objective To examine the association between serum concentrations of total cholesterol, high density lipoprotein cholesterol (HDL), low density lipoprotein cholesterol, triglycerides, apolipoprotein A-I (apoA), apolipoprotein B and the incidence of colorectal cancer (CRC). Design Nested case–control study. Setting The study was conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC), a cohort of more than 520 000 participants from 10 western European countries. Participants 1238 cases of incident CRC, which developed after enrolment into the cohort, were matched with 1238 controls for age, sex, centre, follow-up time, time of blood collection and fasting status. Main outcome measures Serum concentrations were quantitatively determined by colorimetric and turbidimetric methods. Dietary and lifestyle data were obtained from questionnaires. Conditional logistic regression models were used to estimate incidence rate ratios (RRs) and 95% CIs which were adjusted for height, weight, smoking habits, physical activity, education, consumption of fruit, vegetables, meat, fish, alcohol, fibre and energy. Results After adjustments, the concentrations of HDL and apoA were inversely associated with the risk of colon cancer (RR for 1 SD increase of 16.6 mg/dl in HDL and 32.0 mg/dl in apoA of 0.78 (95% CI 0.68 to 0.89) and 0.82 (95% CI 0.72 to 0.94), respectively). No association was observed with the risk of rectal cancer. Additional adjustment for biomarkers of systemic inflammation, insulin resistance and oxidative stress or exclusion of the first 2 years of follow-up did not influence the association between HDL and risk of colon cancer. Conclusions These findings show that high concentrations of serum HDL are associated with a decreased risk of colon cancer. The mechanism behind this association needs further elucidation.

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OBJECTIVES: This study sought to investigate abnormalities in coronary circulatory function in 2 different disease entities of obese (OB) and morbidly obese (MOB) individuals and to evaluate whether these would differ in severity with different profiles of endocannabinoids, leptin, and C-reactive protein (CRP) plasma levels. BACKGROUND: There is increasing evidence that altered plasma levels of endocannabinoids, leptin, and CRP may affect coronary circulatory function in OB and MOB. METHODS: Myocardial blood flow (MBF) responses to cold pressor test from rest and during pharmacologically induced hyperemia were measured with N-13 ammonia positron emission tomography/computed tomography. Study participants (n = 111) were divided into 4 groups based on their body mass index (BMI) (kg/m(2)): 1) control group (BMI: 20 to 24.9, n = 30); 2) overweight group (BMI: 25 to 29.9, n = 31), 3) OB group (BMI: 30 to 39.9, n = 25); and 4) MOB group (BMI ≥40, n = 25). RESULTS: The cold pressor test-induced change in endothelium-related MBF response (ΔMBF) progressively declined in overweight and OB groups when compared with the control group [median: 0.19 (interquartile range [IQR] 0.08, 0.27) and 0.11 (0.03, 0.17) vs. 0.27 (0.23, 0.38) ml/g/min; p ≤ 0.01, respectively], whereas it did not differ significantly between OB and MOB groups [median: 0.11 (IQR: 0.03, 0.17) and 0.09 (-0.01, 0.19) ml/g/min; p = 0.93]. Compared with control subjects, hyperemic MBF subjects comparably declined in the overweight, OB, and MOB groups [median: 2.40 (IQR 1.92, 2.63) vs. 1.94 (1.65, 2.30), 2.05 (1.67, 2.38), and 2.14 (1.78, 2.76) ml/g/min; p ≤ 0.05, respectively]. In OB individuals, ΔMBF was inversely correlated with increase in endocannabinoid anandamide (r = -0.45, p = 0.044), but not with leptin (r = -0.02, p = 0.946) or with CRP (r = -0.33, p = 0.168). Conversely, there was a significant and positive correlation among ΔMBF and elevated leptin (r = 0.43, p = 0.031) and CRP (r = 0.55, p = 0.006), respectively, in MOB individuals that was not observed for endocannabinoid anandamide (r = 0.07, p = 0.740). CONCLUSIONS: Contrasting associations of altered coronary endothelial function with increases in endocannabinoid anandamide, leptin, and CRP plasma levels identify and characterize OB and MOB as different disease entities affecting coronary circulatory function.

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BACKGROUND Recent advances in characterizing the immune recovery of HIV-1-infected people have highlighted the importance of the thymus for peripheral T-cell diversity and function. The aim of this study was to investigate differences in immune reconstitution profiles after highly active antiretroviral therapy (HAART) between HIV-children and adults. METHODS HIV patients were grouped according to their previous clinical and immunological status: 9 HIV-Reconstituting-adults (HIV-Rec-adults) and 10 HIV-Reconstituting-children (HIV-Rec-children) on HAART with viral load (VL) and CD4+ >or=500 cells/microL at least during 6 months before the study and CD4+ and 20 healthy-children (control subjects) were used to calculate Z-score values to unify value scales between children and adults to make them comparable. RESULTS HIV-Rec-children had higher T-cell receptor excision circles (TREC) and lower interleukin (IL)-7 levels than HIV-Rec-adults (p < 0.05). When we analyzed Z-score values, HIV-Rec-children had higher TREC Z-score levels (p = 0.03) than HIV-Rec-adults but similar IL-7 Z-score levels. Regarding T-cell subsets, HIV-Rec-children had higher naïve CD4+ (CD4+CD45RA hi+CD27+), naïve CD8+ (CD8+CD45RA hi+CD27+), and memory CD8+ (CD8+CD45RO+) cells/microl than HIV-Rec-adults, but similar memory CD4+ (CD4+CD45RO+) counts. HIV-Rec-children had lower naïve CD8+ Z-score values than HIV-Rec-adults (p = 0.05). CONCLUSION Our data suggest that HIV-Rec-children had better thymic function than HIV-Rec-adults and this fact affects the peripheral T-cell subsets. Thus, T-cell recovery after HAART in HIV-Rec-adults could be the consequence of antigen-independent peripheral T-cell expansion while in HIV-Rec-children thymic output could play a predominant role in immune reconstitution.

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Niche conservatism, the tendency of a species niche to remain unchanged over time, is often assumed when discussing, explaining or predicting biogeographical patterns. Unfortunately, there has been no basis for predicting niche dynamics over relevant timescales, from tens to a few hundreds of years. The recent application of species distribution models (SDMs) and phylogenetic methods to analysis of niche characteristics has provided insight to niche dynamics. Niche shifts and conservatism have both occurred within the last 100 years, with recent speciation events, and deep within clades of species. There is increasing evidence that coordinated application of these methods can help to identify species which likely fulfill one key assumption in the predictive application of SDMs: an unchanging niche. This will improve confidence in SDM-based predictions of the impacts of climate change and species invasions on species distributions and biodiversity.

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The author studies the error and complexity of the discrete random walk Monte Carlo technique for radiosity, using both the shooting and gathering methods. The author shows that the shooting method exhibits a lower complexity than the gathering one, and under some constraints, it has a linear complexity. This is an improvement over a previous result that pointed to an O(n log n) complexity. The author gives and compares three unbiased estimators for each method, and obtains closed forms and bounds for their variances. The author also bounds the expected value of the mean square error (MSE). Some of the results obtained are also shown

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OBJECTIVE. The main goal of this paper is to obtain a classification model based on feed-forward multilayer perceptrons in order to improve postpartum depression prediction during the 32 weeks after childbirth with a high sensitivity and specificity and to develop a tool to be integrated in a decision support system for clinicians. MATERIALS AND METHODS. Multilayer perceptrons were trained on data from 1397 women who had just given birth, from seven Spanish general hospitals, including clinical, environmental and genetic variables. A prospective cohort study was made just after delivery, at 8 weeks and at 32 weeks after delivery. The models were evaluated with the geometric mean of accuracies using a hold-out strategy. RESULTS. Multilayer perceptrons showed good performance (high sensitivity and specificity) as predictive models for postpartum depression. CONCLUSIONS. The use of these models in a decision support system can be clinically evaluated in future work. The analysis of the models by pruning leads to a qualitative interpretation of the influence of each variable in the interest of clinical protocols.

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BACKGROUND AND AIMS: Ficolin-2 is an acute phase reactant produced by the liver and targeted to recognize N-acetyl-glucosamine which is present in bacterial and fungal cell walls. We recently showed that ficolin-2 serum levels were significantly higher in CD patients compared to healthy controls. We aimed to evaluate serum ficolin-2 concentrations in CD patients regarding their correlation with endoscopic severity and to compare them with clinical activity, fecal calprotectin, and CRP. METHODS: Patients provided fecal and blood samples before undergoing ileo-colonoscopy. Disease activity was scored clinically according to the Harvey-Bradshaw Index (HBI) and endoscopically according to the simplified endoscopic score for CD (SES-CD). Ficolin-2 serum levels and fecal calprotectin levels were measured by ELISA. RESULTS: A total of 136 CD patients were prospectively included (mean age at inclusion 41.5±15.4 years, 37.5% females). Median HBI was 3 [2-6] points, median SES-CD was 5 [2-8], median fecal calprotectin was 301 [120-703] μg/g, and median serum ficolin-2 was 2.69 [2.02-3.83] μg/mL. SES-CD correlated significantly with calprotectin (R=0.676, P<0.001), CRP (R=0.458, P<0.001), HBI (R=0.385, P<0.001), and serum ficolin-2 levels (R=0.171, P=0.047). Ficolin-2 levels were higher in CD patients with mild endoscopic disease compared to patients in endoscopic remission (P=0.015) but no difference was found between patients with mild, moderate, and severe endoscopic disease. CONCLUSIONS: Ficolin-2 serum levels correlate worse with endoscopic CD activity when compared to fecal calprotectin or CRP.