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101.
BackgroundCMV reactivation, which enhances immune senescence, could be associated with a higher risk of cancer.ObjectivesWe compared the prevalence of positive CMV DNAemia in HIV-infected patients with and without cancer.Study designThis case–control study, nested in the ANRS-CO3 Aquitaine Cohort, included patients with a first diagnosis of cancer (2002–2007) as cases. Two controls were matched per case.Cancer risk was estimated using conditional logistic regression models, an Odds Ratio (OR) of 2 could be detected with 80% power. The variables considered were: ≥1 positive CMV DNAemia, CD4+ and CD8+ counts, HIV plasma load. Plasma CMV DNA was retrospectively quantified within the 3-year period preceding the endpoint.ResultsThe 143 cases (93 non-AIDS-related and 50 AIDS-related cancers) and 284 controls had a median age of 47 years (IQR: 41–56). At the time of diagnosis or censorship, for cases and controls, median values were respectively, for CD4+ count: 327 cells/mm3 (IQR: 164–514) and 416 (IQR: 275–582), and for HIV plasma load: 2.6 log10 copies/mL (IQR: 1.7–4.7) and 1.7 log10 copies/mL (IQR: 1.7–3.3). We performed 2056 CMV PCR; 14 cases (9.8% [95% CI: 4.9–14.7]) and 19 controls (6.7% [CI: 3.8–9.6]) presented ≥1 positive PCR. CMV DNAemia was not associated with the risk of cancer (unadjusted and adjusted p-values = 0.19 and 0.54, respectively). HIV load >500 copies/mL was independently associated with a higher risk of cancer (OR = 2.02; p = 0.002; 95% CI: 1.29–3.17).ConclusionThis large case–control study did not show any differential exposure to positive CMV plasma DNAemia between cancer cases and controls.  相似文献   
102.
103.
Holt-Oram syndrome (HOS) is a rare, autosomal dominant heart-hand syndrome caused by mutations in the TBX5 gene. A wide spectrum of TBX5 mutations have been reported previously, most resulting in a null allele leading to haploinsufficiency. TBX5 gene duplications have been previously reported in association with typical and atypical HOS phenotypes. Ulnar-Mammary syndrome (UMS) is a distinct rare, autosomal dominant condition caused by mutations in the TBX3 gene. TBX5 and TBX3 are physically linked in cis on human chromosome 12 and contiguous chromosome 12q24 deletions comprising both TBX5 and TBX3 genes have been previously reported but to our knowledge, duplications have never been described. We report on a large German family with at least 17 affected individuals over 6 generations bearing a duplication at 12q24.21 identified on array-CGH comprising both TBX5 and TBX3 genes. Affected patients are presenting with HOS and UMS symptoms, consisting of variable limb anomalies involving the radial and the ulnar rays and cardiac findings such as congenital heart defects, persistent arterial duct or aortic stenosis, and non-classical symptoms, such as supernumerary nipples and cardiomyopathy. Fluorescence in situ hybridisation confirmed a tandem duplication at the 12q24.21 locus. This is the first report of a contiguous TBX3/TBX5 duplication associated with HOS/UMS phenotype.  相似文献   
104.
Heterogeneity of NSD1 alterations in 116 patients with Sotos syndrome   总被引:1,自引:0,他引:1  
Sotos syndrome is an overgrowth syndrome characterized by distinctive facial features, learning difficulties, and macrocephaly with frequent pre- and postnatal overgrowth with advanced bone age. Here, we report on our experience in the molecular diagnostic of Sotos syndrome on 116 patients. Using direct sequencing and a quantitative multiplex PCR of short fluorescent fragments (QMPSF)-based assay allowing accurate detection of both total and partial NSD1 deletions, we identified NSD1 abnormalities in 104 patients corresponding to 102 Sotos families (90%). NSD1 point mutations were detected in 80% of the index cases, large deletions removing the NSD1 gene entirely in 14%, and intragenic NSD1 rearrangements in 6%. Among the 69 detected distinct point mutations, 48 were novel. The QMPSF assay detected an exonic duplication and a mosaic partial deletion. QMPSF mapping of the 15 large deletions revealed the heterogeneity of the deletions, which vary in size from 1 to 4.5 Mb. Clinical features of NSD1-positive Sotos patients revealed that the phenotype in patients with nontruncating mutations was less severe that in patients with truncating mutations. This study confirms the heterogeneity of NSD1 alterations in Sotos syndrome and therefore the need to complete sequencing analysis by screening for partial deletions and duplications to ensure an accurate molecular diagnosis of this syndrome.  相似文献   
105.
The factors determining maximal oxygen consumption were explored in eight endurance trained subjects (TS) and eight untrained subjects (US) exposed to moderate acute normobaric hypoxia. Subjects performed maximal incremental tests at sea level and simulated altitudes (1,000, 2,500, 4,500 m). Heart rate (HR), stroke volume (SV), cardiac output arterialized oxygen saturation oxygen uptake ventilation ( expressed in normobaric conditions) were measured. At maximal exercise, ventilatory equivalent transport and O2 extraction (O2ERmax) were calculated. In TS, remained unchanged despite a significant reduction in at 4,500 m. SVmax remained unchanged. decreased in TS at 4,500 m, was lower in TS and greater at 4,500 m vs. sea level in both groups. Sa′O2max decreased at and above 1,000 m in TS and 2,500 m in US, O2ERmax increased at 4,500 m in both groups. decreased with altitude and was greater in TS than US up to 2,500 m but not at 4,500 m. decreased with altitude but the decrement was larger in TS at 4,500 m. In both groups in moderate hypoxia was correlated with Several differences between the two groups are probably responsible for the greater in TS at 4,500 m : (1) the relative hypoventilation in TS as shown by the decrement in at 4,500 m (2) the greater decrement in TS due to a lower Sa′O2max and unchanged 3) the smaller increase in O2ERmax in TS, insufficient to compensate the decrease in   相似文献   
106.
To determine differences in maximal strength and muscle power output of the arm and leg extensor muscles, peak and mean power during a modified standing crank-arm Wingate test, running speed, muscle extensibility, and anthropometric markers between elite and amateurs wrestlers according to the weight classes system; 92 male wrestlers were assigned into 6 groups according to their body mass (light, middle and heavy weight) and their competitive level (elite and amateur): Light Weight (body mass ranged between 55 and 68 kg) in elite (LWE, n = 18) and amateur (LWA, n = 15) level; Middle Weight (body mass ranged between 68 and 84 kg) in elite (MWE, n = 18) and amateur (MWA, n = 19) level; and Heavy Weight (body mass ranged between 84 and 100 kg) in elite (HWE, n = 10) and amateur (HWA, n = 12) level. Elite wrestlers were older (8–12%), had more training experience (25–37%), fat-free mass (3–5%), maximal strength in absolute and relative terms (8–25%), muscle power (14–30%), mean and peak power during crank-arm Wingate testing in absolute and relative terms (13–22%), jumping height (8–17%) as well as grip (6–19%) and back strength (7–20%) compared to amateur wrestlers. However, no differences were observed between elite and amateur groups in height, body mass index, percentage of body fat, hamstring extensibility and running speed. The present results suggest that the higher absolute and relative values of maximal strength, muscle power, and anaerobic metabolism, explained in part by the differences in lean mass and neural activation patterns, will give elite wrestlers a clear advantage during the most frequently used techniques in Olympic wrestling.  相似文献   
107.
Despite national guidelines, medical practices and kidney transplant waiting list registration policies may differ from one dialysis/transplant unit to another. Benefit risk assessment variations, especially for elderly patients, have also been described. The aim of this study was to identify sources of variation in early kidney transplant waiting list registration in France. Among 16 842 incident patients during the period 2016–2017, 4386 were registered on the kidney transplant waiting list at the start of, or during the first year after starting, dialysis (26%). We developed various log-linear mixed effect regression models on three levels: patients, dialysis networks, and transplant centers. Variability was expressed as variance from the random intercepts (± standard error). Although patient characteristics have an important impact on the likelihood of registration, the overall magnitude of variability in registration was low and shared by dialysis networks and transplant centers. Between-transplant center variability (0.23 ± 0.08) was 1.8 higher than between-dialysis network variability (0.13 ± 0.004). Older age was associated with a lower probability of registration and greater variability between networks (0.04, 0.20, & 0.93 in the 18–64, 65–74, and 75–84 age groups). Targeted interventions should focus on elderly patients and/or certain regions with greater variability in waiting list access.  相似文献   
108.
This paper covers work in virtual reality-based, patient-specific surgical planning over the past decade. It aims to comprehensively examine the user interface paradigms and system designs during that period of time and to objectively analyze their effectiveness for the task. The goal is to provide useful feedback on these interface and implementation paradigms to aid other researchers in this field. First, specialized systems for specific clinical use were produced with a limited set of visualization tools. Later, through collaboration with NASA, an immersive virtual environment was created to produce high-fidelity images for surgical simulation, but it underestimated the importance of collaboration. The next system, a networked, distributed virtual environment, provided immersion and collaboration, but the immersive paradigm was found to be of a disadvantage and the uniqueness of the framework unwieldy. A virtual model, workbench-style display was then created using a commercial package, but limitations of each were soon apparent. Finally, a specialized display, with an integrated visualization and simulation system is described and evaluated. Lessons learned include: surgical planning is an abstract process unlike surgical simulation; collaboration is important, as is stereo visualization; and that high-resolution preoperative images from standard viewpoints are desirable, but interaction is truly the key to planning.  相似文献   
109.
OBJECTIVE: MDCT has improved the management of hemoptysis by providing more precise depiction of bronchial and nonbronchial systemic arteries than conventional CT. The purpose of this article is to review the role of MDCT in the identification of the bleeding site and the vessels causing hemoptysis. CONCLUSION: Identification of the origin of the involved systemic arteries (bronchial and nonbronchial) or involved pulmonary artery on MDCT enables the interventional radiologist to treat them, especially in elderly patients with a tortuous aorta and atheroma.  相似文献   
110.
G P Lefort  S Amr  P Carayon  B C Nisula 《Endocrinology》1984,114(3):1005-1011
TSH is known to interact on thyroid membranes with two classes of binding sites that differ in affinity and capacity. To assess the relevance of the class of TSH-binding sites characterized by low affinity and high capacity to the stimulation of adenylate cyclase, we studied the interactions of desialylated hCG (as-hCG) and its beta-subunit (as-hCG beta) with human thyroid membranes. In low ionic strength buffer, pH 7.8, where both classes of sites are operant, as-hCG fully inhibited and as-hCG beta partially inhibited [125I] bovine (b) TSH binding. Scatchard analysis of the [125I]bTSH binding inhibition curve in the presence of 1.0 X 10(-5) M as-hCG beta clearly indicated that as-hCG beta interacted only with the low affinity class of binding sites, leaving the high affinity class unaffected. In the presence of 140 mM NaCl, [125I]bTSH interacted predominantly with the high affinity class of binding sites; as-hCG fully inhibited [125I]bTSH binding to this class of sites, whereas as-hCG beta displayed essentially no interaction. Scatchard analysis of [125I]as-hCG beta binding to human thyroid membranes in low ionic strength buffer revealed a single apparent class of sites with low affinity (Kd = approximately 1.0 X 10(-6) M) and high capacity (Q = approximately 300 pmol/mg membrane protein). The bTSH preparation (Thytropar) showed a 10-fold greater binding inhibition potency at these sites than either the as-hCG or the as-hCG beta preparation, in keeping with the inference that as-hCG beta interacts with the low affinity class of TSH-binding sites. At a concentration more than 3 times that necessary to inhibit TSH binding to the low affinity class of sites, the as-hCG beta molecule neither stimulated adenylate cyclase nor inhibited the ability of TSH to do so. In contrast, the as-hCG molecule, which interacts with both classes of TSH-binding sites, fully inhibited TSH stimulation of adenylate cyclase. We conclude that the low affinity class of TSH-binding sites is not the class of sites through which TSH stimulates adenylate cyclase, and that this role is best ascribed to the high affinity class of TSH-binding sites.  相似文献   
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