59 resultados para VARIABLE SAMPLING INTERVAL X(OVER-BAR) CHART
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Alcohol and tobacco consumption are well-recognized risk factors for head and neck cancer (HNC). Evidence suggests that genetic predisposition may also play a role. Only a few epidemiologic studies, however, have considered the relation between HNC risk and family history of HNC and other cancers. We pooled individual-level data across 12 case-control studies including 8,967 HNC cases and 13,627 controls. We obtained pooled odds ratios (OR) using fixed and random effect models and adjusting for potential confounding factors. All statistical tests were two-sided. A family history of HNC in first-degree relatives increased the risk of HNC (OR=1.7, 95% confidence interval, CI, 1.2-2.3). The risk was higher when the affected relative was a sibling (OR=2.2, 95% CI 1.6-3.1) rather than a parent (OR=1.5, 95% CI 1.1-1.8) and for more distal HNC anatomic sites (hypopharynx and larynx). The risk was also higher, or limited to, in subjects exposed to tobacco. The OR rose to 7.2 (95% CI 5.5-9.5) among subjects with family history, who were alcohol and tobacco users. A weak but significant association (OR=1.1, 95% CI 1.0-1.2) emerged for family history of other tobacco-related neoplasms, particularly with laryngeal cancer (OR=1.3, 95% CI 1.1-1.5). No association was observed for family history of nontobacco-related neoplasms and the risk of HNC (OR=1.0, 95% CI 0.9-1.1). Familial factors play a role in the etiology of HNC. In both subjects with and without family history of HNC, avoidance of tobacco and alcohol exposure may be the best way to avoid HNC.
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Social organisation of colonies was examined in the ant Formica cinerea by estimating the coefficient of genetic relatedness among worker nest mates. The estimates based on microsatellite genotypes at three loci ranged from values close to zero to 0.61 across the populations studied in Finland. These results showed that a fundamental feature of colonies, the number of reproductive queens, varied greatly among the populations. Colonies in some populations had a single queen, whereas the nests could have a high number number of queens in other populations. There was a weak but non-significant correlation between the genetic and metric distance of nests within two populations with intermediate level of relatedness. Differentiation among nearby populations (within the dispersal distance of individuals) in one locality indicated limited dispersal or founder effects. This could occur when females are philopatric and stay in the natal polygynous colony which expands by building a network of nest galleries within a single habitat patch.
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PURPOSE: To investigate the potential of free-breathing 3D steady-state free precession (SSFP) imaging with radial k-space sampling for coronary MR-angiography (MRA), coronary projection MR-angiography and coronary vessel wall imaging. MATERIALS AND METHODS: A navigator-gated free-breathing T2-prepared 3D SSFP sequence (TR = 6.1 ms, TE = 3.0 ms, flip angle = 120 degrees, field-of-view = 360 mm(2)) with radial k-space sampling (384 radials) was implemented for coronary MRA. For projection coronary MRA, this sequence was combined with a 2D selective aortic spin tagging pulse. Coronary vessel wall imaging was performed using a high-resolution inversion-recovery black-blood 3D radial SSFP sequence (384 radials, TR = 5.3 ms, TE = 2.7 ms, flip angle = 55 degrees, reconstructed resolution 0.35 x 0.35 x 1.2 mm(3)) and a local re-inversion pulse. Six healthy volunteers (two for each sequence) were investigated. Motion artifact level was assessed by two radiologists. Results: In coronary MRA, the coronary lumen was displayed with a high signal and high contrast to the surrounding lumen. Projection coronary MRA demonstrated selective visualization of the coronary lumen while surrounding tissue was almost completely suppressed. In coronary vessel wall imaging, the vessel wall was displayed with a high signal when compared to the blood pool and the surrounding tissue. No visible motion artifacts were seen. Conclusion: 3D radial SSFP imaging enables coronary MRA, coronary projection MRA and coronary vessel wall imaging with a low motion artifact level.
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Objectives. The goal of this study is to evaluate a T2-mapping sequence by: (i) measuring the reproducibility intra- and inter-observer variability in healthy volunteers in two separate scanning session with a T2 reference phantom; (2) measuring the mean T2 relaxation times by T2-mapping in infarcted myocardium in patients with subacute MI and compare it with patient's the gold standard X-ray coronary angiography and healthy volunteers results. Background. Myocardial edema is a consequence of an inflammation of the tissue, as seen in myocardial infarct (MI). It can be visualized by cardiovascular magnetic resonance (CMR) imaging using the T2 relaxation time. T2-mapping is a quantitative methodology that has the potential to address the limitation of the conventional T2-weighted (T2W) imaging. Methods. The T2-mapping protocol used for all MRI scans consisted in a radial gradient echo acquisition with a lung-liver navigator for free-breathing acquisition and affine image registration. Mid-basal short axis slices were acquired.T2-maps analyses: 2 observers semi- automatically segmented the left ventricle in 6 segments accordingly to the AHA standards. 8 healthy volunteers (age: 27 ± 4 years; 62.5% male) were scanned in 2 separate sessions. 17 patients (age : 61.9 ± 13.9 years; 82.4% male) with subacute STEMI (70.6%) and NSTEMI underwent a T2-mapping scanning session. Results. In healthy volunteers, the mean inter- and intra-observer variability over the entire short axis slice (segment 1 to 6) was 0.1 ms (95% confidence interval (CI): -0.4 to 0.5, p = 0.62) and 0.2 ms (95% CI: -2.8 to 3.2, p = 0.94, respectively. T2 relaxation time measurements with and without the correction of the phantom yielded an average difference of 3.0 ± 1.1 % and 3.1 ± 2.1 % (p = 0.828), respectively. In patients, the inter-observer variability in the entire short axis slice (S1-S6), was 0.3 ms (95% CI: -1.8 to 2.4, p = 0.85). Edema location as determined through the T2-mapping and the coronary artery occlusion as determined on X-ray coronary angiography correlated in 78.6%, but only in 60% in apical infarcts. All except one of the maximal T2 values in infarct patients were greater than the upper limit of the 95% confidence interval for normal myocardium. Conclusions. The T2-mapping methodology is accurate in detecting infarcted, i.e. edematous tissue in patients with subacute infarcts. This study further demonstrated that this T2-mapping technique is reproducible and robust enough to be used on a segmental basis for edema detection without the need of a phantom to yield a T2 correction factor. This new quantitative T2-mapping technique is promising and is likely to allow for serial follow-up studies in patients to improve our knowledge on infarct pathophysiology, on infarct healing, and for the assessment of novel treatment strategies for acute infarctions.
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Immigrants from high-burden countries and HIV-coinfected individuals are risk groups for tuberculosis (TB) in countries with low TB incidence. Therefore, we studied their role in transmission of Mycobacterium tuberculosis in Switzerland. We included all TB patients from the Swiss HIV Cohort and a sample of patients from the national TB registry. We identified molecular clusters by spoligotyping and mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) analysis and used weighted logistic regression adjusted for age and sex to identify risk factors for clustering, taking sampling proportions into account. In total, we analyzed 520 TB cases diagnosed between 2000 and 2008; 401 were foreign born, and 113 were HIV coinfected. The Euro-American M. tuberculosis lineage dominated throughout the study period (378 strains; 72.7%), with no evidence for another lineage, such as the Beijing genotype, emerging. We identified 35 molecular clusters with 90 patients, indicating recent transmission; 31 clusters involved foreign-born patients, and 15 involved HIV-infected patients. Birth origin was not associated with clustering (adjusted odds ratio [aOR], 1.58; 95% confidence interval [CI], 0.73 to 3.43; P = 0.25, comparing Swiss-born with foreign-born patients), but clustering was reduced in HIV-infected patients (aOR, 0.49; 95% CI, 0.26 to 0.93; P = 0.030). Cavitary disease, male sex, and younger age were all associated with molecular clustering. In conclusion, most TB patients in Switzerland were foreign born, but transmission of M. tuberculosis was not more common among immigrants and was reduced in HIV-infected patients followed up in the national HIV cohort study. Continued access to health services and clinical follow-up will be essential to control TB in this population.
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PURPOSE: The aim of this study was to examine whether lipid oxidation predominates during 3 h of postexercise recovery in high-intensity interval exercise as compared with moderate-intensity continuous exercise on a cycle ergometer in fit young men (n = 12; 24.6 +/- 0.6 yr). METHODS: The energy substrate partitioning was evaluated during and after high-intensity submaximal interval exercise (INT, 1-min intervals at 80% of maximal aerobic power output [Wmax] with an intervening 1 min of active recovery at 40% Wmax) and 60-min moderate-intensity continuous exercise at 45% of maximal oxygen uptake (C45%) as well as a time-matched resting control trial (CON). Exercise bouts were matched for mechanical work output. RESULTS: During exercise, a significantly greater contribution of CHO and a lower contribution of lipid to energy expenditure were found in INT (512.7 +/- 26.6 and 41.0 +/- 14.0 kcal, respectively) than in C45% (406.3 +/- 21.2 and 170.3 +/- 24.0 kcal, respectively; P < 0.001) despite similar overall energy expenditure in both exercise trials (P = 0.13). During recovery, there were no significant differences between INT and C45% in substrate turnover and oxidation (P > 0.05). On the other hand, the mean contribution of lipids to energy yield was significantly higher after exercise trials (C45% = 61.3 +/- 4.2 kcal; INT = 66.7 +/- 4.7 kcal) than after CON (51.5 +/- 3.4 kcal; P < 0.05). CONCLUSIONS: These findings show that lipid oxidation during postexercise recovery was increased by a similar amount on two isoenergetic exercise bouts of different forms and intensities compared with the time-matched no-exercise control trial.
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BACKGROUND: Antinucleosome autoantibodies were previously described to be a marker of active lupus nephritis. However, the true prevalence of antinucleosome antibodies at the time of active proliferative lupus nephritis has not been well established. Therefore, the aim of this study is to define the prevalence and diagnostic value of autoantibodies against nucleosomes as a marker for active proliferative lupus nephritis. STUDY DESIGN: Prospective multicenter diagnostic test study. SETTING & PARTICIPANTS: 35 adult patients with systemic lupus erythematosus (SLE) at the time of the renal biopsy showing active class III or IV lupus nephritis compared with 59 control patients with SLE. INDEX TEST: Levels of antinucleosome antibodies and anti-double-stranded DNA (anti-dsDNA) antibodies. REFERENCE TEST: Kidney biopsy findings of class III or IV lupus nephritis at the time of sampling in a study population versus clinically inactive or no nephritis in a control population. RESULTS: Increased concentrations of antinucleosome antibodies were found in 31 of 35 patients (89%) with active proliferative lupus nephritis compared with 47 of 59 control patients (80%) with SLE. No significant difference between the 2 groups with regard to number of positive patients (P = 0.2) or antibody concentrations (P = 0.2) could be found. The area under the receiver operating characteristic curve as a marker of the accuracy of the test in discriminating between proliferative lupus nephritis and inactive/no nephritis in patients with SLE was 0.581 (95% confidence interval, 0.47 to 0.70; P = 0.2). Increased concentrations of anti-dsDNA antibodies were found in 33 of 35 patients (94.3%) with active proliferative lupus nephritis compared with 49 of 58 control patients (84.5%) with SLE (P = 0.2). In patients with proliferative lupus nephritis, significantly higher titers of anti-dsDNA antibodies were detected compared with control patients with SLE (P < 0.001). The area under the receiver operating characteristic curve in discriminating between proliferative lupus nephritis and inactive/no nephritis in patients with SLE was 0.710 (95% confidence interval, 0.60 to 0.82; P < 0.001). CONCLUSIONS: Antinucleosome antibodies have a high prevalence in patients with severe lupus nephritis. However, our data suggest that determining antinucleosome antibodies is of limited help in the distinction of patients with active proliferative lupus nephritis from patients with SLE without active renal disease.
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BACKGROUND: Co-morbidity information derived from administrative data needs to be validated to allow its regular use. We assessed evolution in the accuracy of coding for Charlson and Elixhauser co-morbidities at three time points over a 5-year period, following the introduction of the International Classification of Diseases, 10th Revision (ICD-10), coding of hospital discharges.METHODS: Cross-sectional time trend evaluation study of coding accuracy using hospital chart data of 3'499 randomly selected patients who were discharged in 1999, 2001 and 2003, from two teaching and one non-teaching hospital in Switzerland. We measured sensitivity, positive predictive and Kappa values for agreement between administrative data coded with ICD-10 and chart data as the 'reference standard' for recording 36 co-morbidities.RESULTS: For the 17 the Charlson co-morbidities, the sensitivity - median (min-max) - was 36.5% (17.4-64.1) in 1999, 42.5% (22.2-64.6) in 2001 and 42.8% (8.4-75.6) in 2003. For the 29 Elixhauser co-morbidities, the sensitivity was 34.2% (1.9-64.1) in 1999, 38.6% (10.5-66.5) in 2001 and 41.6% (5.1-76.5) in 2003. Between 1999 and 2003, sensitivity estimates increased for 30 co-morbidities and decreased for 6 co-morbidities. The increase in sensitivities was statistically significant for six conditions and the decrease significant for one. Kappa values were increased for 29 co-morbidities and decreased for seven.CONCLUSIONS: Accuracy of administrative data in recording clinical conditions improved slightly between 1999 and 2003. These findings are of relevance to all jurisdictions introducing new coding systems, because they demonstrate a phenomenon of improved administrative data accuracy that may relate to a coding 'learning curve' with the new coding system.
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OBJECTIVES: The aim of the present study is to investigate the demographics, aetiologies, complications, treatments and visual outcomes in paediatric uveitis patients in the French-speaking part of Switzerland. METHODS: Chart review of all patients diagnosed with uveitis before the age of 16 years, presenting to two tertiary referral centres (uveitis and paediatric rheumatology clinics) in Lausanne, Switzerland, between 2000 and 2009. RESULTS: Seventy-nine children (37 girls) were identified, 62 living in Switzerland, 15 in Europe and 2 in North Africa. Median age at first symptoms was 9.0 years (range 1.5-15.8 years), with a median follow-up time of 1.8 years (0-8 years). Both eyes were involved in 51 patients (64.6%). The course was acute in 30.4%, chronic in 60.8% and recurrent in 8.9%. Anterior uveitis occurred in 39.2%, intermediate in 32.9%, posterior in 22.8% and panuveitis in 5.1%. The three main diagnoses were idiopathic uveitis (34.2%), JIA-related uveitis (22.8%) and toxoplasmic retinochoroiditis (15.2%). During the last follow-up visit, the visual acuity (VA) was ≥8/10 in 72% of all eyes with a measurable VA. Cataract (8%), ocular hypertension/glaucoma (8%) and macular fibrosis (4%) were the three most common severe complications. Systemic steroids were given to 56% and biological agents to 24% of patients with inflammatory uveitis. CONCLUSIONS: Uveitis in children can be a devastating disease. A strict classification of aetiologies and a tight collaboration between paediatric rheumatologists and ophthalmologists are important to ensure early control of ocular inflammation and improve long-term visual prognosis.
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OBJECTIVE: HIV-infected children have impaired antibody responses after exposure to certain antigens. Our aim was to determine whether HIV-infected children had lower varicella zoster virus (VZV) antibody levels compared with HIV-infected adults or healthy children and, if so, whether this was attributable to an impaired primary response, accelerated antibody loss, or failure to reactivate the memory VZV response. METHODS: In a prospective, cross-sectional and retrospective longitudinal study, we compared antibody responses, measured by enzyme-linked immunosorbent assay (ELISA), elicited by VZV infection in 97 HIV-infected children and 78 HIV-infected adults treated with antiretroviral therapy, followed over 10 years, and 97 age-matched healthy children. We also tested antibody avidity in HIV-infected and healthy children. RESULTS: Median anti-VZV immunoglobulin G (IgG) levels were lower in HIV-infected children than in adults (264 vs. 1535 IU/L; P<0.001) and levels became more frequently unprotective over time in the children [odds ratio (OR) 17.74; 95% confidence interval (CI) 4.36-72.25; P<0.001]. High HIV viral load was predictive of VZV antibody waning in HIV-infected children. Anti-VZV antibodies did not decline more rapidly in HIV-infected children than in adults. Antibody levels increased with age in healthy (P=0.004) but not in HIV-infected children. Thus, antibody levels were lower in HIV-infected than in healthy children (median 1151 IU/L; P<0.001). Antibody avidity was lower in HIV-infected than healthy children (P<0.001). A direct correlation between anti-VZV IgG level and avidity was present in HIV-infected children (P=0.001), but not in healthy children. CONCLUSION: Failure to maintain anti-VZV IgG levels in HIV-infected children results from failure to reactivate memory responses. Further studies are required to investigate long-term protection and the potential benefits of immunization.
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Short-term dynamic psychotherapy (STDP) has rarely been investigated with regard to its underlying mechanisms of change, even if psychoanalytic theory informs us about several potential putative mechanisms of change in patients. Change in overall defensive functioning is one. In this study, we explored the role of overall defensive functioning, by comparing it on the process level with the neighbouring concept of overall coping functioning. A total of N=32 patients, mainly presenting adjustment disorder, were included in the study. The patients underwent STDP up to 40 sessions; three sessions per psychotherapy were transcribed and analyzed by using two observer-rating scales: Defense Mechanism Rating Scales (Perry, 1990) and Coping Action Patterns (Perry, Drapeau, Dunkley, & Blake, 2005). Hierarchical linear modeling was applied to model the change over the course of therapy and relate it to outcome. Results suggest that STDP has an effect on the target variable of overall defensive functioning, which was absent for overall coping functioning. Links with outcome confirm the importance of the effect. These results are discussed from methodological and clinical viewpoints.
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Aims and objectives This study aimed to determine the discriminant validity and the test-retest reliability of a questionnaire testing the impact of evidence-based medicine (EBM) training on doctors' knowledge and skills. Methods Questionnaires were sent electronically to all doctors working as residents and chief residents in two French speaking hospital networks in Switzerland. Participants completed the questionnaire twice, within a 4-week interval. The discriminant validity was examined in comparing doctors' performance according to their reported EBM previous training. Proportion of agreement between both sessions of the questionnaire, Cohen's kappa and 'uniform kappa' determined its test-retest reliability. Results The participation rate was 9.8%/7.1% to first/second session. Performance increased according to the level of doctors' previous training in EBM. The observed proportion of agreement between both sessions was over 70% for 14/19 questions, and the 'uniform kappa' was superior to 0.60 for 15/19 questions. Conclusion The discriminant validity and test-retest reliability of the questionnaire were satisfying. The low participation rate did not prevent the study from achieving its aims.
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The distribution limits of Crocidura russula (Hermann, 1780) and C. leucodon (Hermann, 1780) were investigated during an interval of 25 years in the bottom of the Rhone valley above Lake Geneva, Switzerland (total data set: 105 spatio-temporal occurrences, 1137 shrews). In 1975, the contact zone between the two species was situated in the region of Martigny. In 1999/2000, new sampling revealed three results: (1) The contact zone showed an upward shift of about 25 km. (2) In the expanded range of C. russula, the resident species has totally disappeared (confirmed by owl pellets analysis). (3) This demonstrates a dominance of C, russula over C. leucodon. Three hypotheses which may explain the range expansion of C. russula were evaluated: (1) habitat modification favouring linear dispersal due to the construction of a highway; (2) temporal event favoured by climate fluctuations, or (3) ongoing postglacial colonisation of Europe. Hypothesis 1 was rejected, because the progression of the shrews anticipated the construction. Hypothesis 3 received only weak support because range limits of C. russula in the region of Nice have been stable for thousands of years. Therefore hypothesis 2, admitting that ongoing climate change has facilitated range expansion, is the most probable.
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Jejunal diverticulosis is a rare entity with variable clinical and anatomical presentations. Its reported incidence varies from 0.05% to 6%. Although there is no consensus on the management of asymptomatic jejunal diverticular disease, some complications are potentially life threatening and require early surgical treatment. We report a case of an 88-year-old man investigated for acute abdominal pain with a high biological inflammatory syndrome. Inflammation of multiple giant jejunal diverticulum was discovered at abdominal computed tomography (CT). As a result of the clinical and biological signs of early peritonitis, an emergency surgical exploration was performed. The first jejunal loop showed clear signs of jejunal diverticulitis. Primary segmental jejunum resection with end-to-end anastomosis was performed. Histopathology report confirmed an ulcerative jejunal diverticulitis with imminent perforation and acute local peritonitis. The patient made an excellent rapid postoperative recovery. Jejunal diverticulum is rare but may cause serious complications. It should be considered a possible etiology of acute abdomen, especially in elderly patients with unusual symptomatology. Abdominal CT is the diagnostic tool of choice. The best treatment is emergency surgical management.