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Many people worldwide are vitamin D (VTD) deficient or insufficient, and there is still no consensus on the dose of VTD that should be administered to achieve a 25(OH)D concentration of 20 or 30 ng/mL. In this study, we aimed to determine an adapted supplementation of VTD able to quickly and safely increase the vitamin D status of healthy adults with low 25(OH)D. One hundred and fifty (150) subjects were randomized into three groups, each to receive, orally, a loading dose of 50,000, 100,000 or 200,000 IU of VTD3 at Week 0, followed by 25,000, 50,000 or 100,000 IU at Week 4 and Week 8. Whereas 25(OH)D baseline values were not different between groups (p = 0.42), a significant increase was observed at Week 12 (p < 0.0001) with a mean change from baseline of 7.72 ± 5.08, 13.3 ± 5.88 and 20.12 ± 7.79 ng/mL. A plateau was reached after eight weeks. No related adverse event was recorded. This study demonstrated a linear dose-response relationship with an increase in 25(OH)D levels proportional to the dose administered. In conclusion, a loading dose of 200,000 IU VTD3 followed by a monthly dose of 100,000 IU is the best dosing schedule to quickly and safely correct the VTD status.  相似文献   
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Multiple mechanisms exist by which tumour cells can escape CD95-mediated apoptosis. Previous studies by our laboratory have shown that primary B cells from non-Hodgkin's Lymphoma (B-NHL) were resistant to CD95-induced cell death. In the current study, we have analysed the mechanisms underlying CD95 resistance in primary human lymphoma B cells. We report that FADD (FAS-associated death domain protein) and caspase-8 were constitutively expressed in lymphoma B cells and that the CD95 pathway was blocked upstream to caspase-8 activation. However, caspase-8 was processed and functional after treatment with staurosporine (STS). We found that the expression levels of FLICE (FADD-like interleukin-1 beta-converting enzyme)-Inhibitory Protein (c-FLIP) and Bcl-2-related proteins were heterogeneous in B-NHL cells and were not related to CD95 resistance. Finally, we report the absence of a CD95-induced signalling complex [death-inducing signalling complex (DISC)] in lymphoma B cells, with no FADD and caspase-8 recruitment to CD95 receptor. In contrast, DISC formation was observed in CD95-resistant non-tumoural (NT) B cells. Therefore, we propose that the absence of DISC formation in primary lymphoma B cells may contribute to protect these cells from CD95-induced apoptosis.  相似文献   
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The gel filtration behavior, in the presence of detergents, of membrane-bound IgM from normal mouse spleen B lymphocytes was compared to that of secretory IgM from mouse plasma cells. The proteins were labeled either by surface radioiodination or biosynthetically with radioactive amino acids. Cell lysates were fractionated on calibrated Sepharose 6B columns in the presence of the detergents Nonidet P-40 or deoxycholate. Eluted fractions were immunoprecipitated and the reduced or unreduced precipitates were analyzed by sodium dodecyl sulfate gel electrophoresis followed by radioautography. Surface (125)I-labeled 8S IgM exhibited a gel filtration pattern in Nonidet P-40 corresponding to much higher apparent molecular weight than that of secretory 8S IgM, a difference that almost disappeared when gel filtration was performed in the presence of deoxycholate, which forms much smaller micelles than does Nonidet P-40. Biosynthetically labeled lymphocytes contain two types of IgM molecules differing in their gel filtration behavior and fate: one identical to secretory 8S IgM of plasma cells and secreted in the medium during chase periods, and the other identical to surface (125)I-labeled IgM and remaining cell-associated. Because the surface-bound 8S IgM was not found to be associated with other labeled molecules, it is likely that the detergent-binding behavior of surface IgM is due to a hydrophobic segment carried by these Ig molecules. That lymphocytes synthesize two types of mu chains was also shown by the use of tunicamycin, an inhibitor of glycosylation. In its presence, two unglycosylated mu chains were observed: one identical in size to that made by tunicamycin-treated plasma cells, and the second slightly larger. Gel filtration in Nonidet P-40 of the cell lysates of tunicamycin-treated lymphocytes showed that the nonsecretory 8S IgM contains this second type of mu chains, whereas the IgM molecules of the secretory type contain plasma cell-like mu chains. It is suggested that membrane IgM mu chains contain a hydrophobic segment which is responsible for its association to the membrane.  相似文献   
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ObjectivesData on the prevalence of Autism Spectrum Disorder (ASD) reveal several clinical evolutions inducing new psychiatric definitions and diagnostic practices. Thus, autism has shifted from being a rare syndrome with severe clinical forms to a new paradigm: the paradigm of “ordinary” or “invisible” autism, in terms of the frequency and the intensity of the disorders. These changes incorporate new populations into our conception of autism, with new phenotypes that pose theoretical and clinical challenges to clinicians. In response, we propose the hypothesis — based on psychoanalytic theories of psychic structures — of an “ordinary autism” as a definition of a non-prototypical autistic psychic functioning that falls outside the DSM diagnostic framework. This idea seems to provide us new theoretical references that nourish our practices as well as fundamental research.MethodFirst, we will review the nosographic mutations of the DSM-5 and their implications for non-prototypical psychic modes of functioning of autistic people that may not be contained within the autism spectrum's blurry boundaries — especially for the adult population without intellectual delay and in the case of complicated differential diagnosis for clinical and societal reasons. Next, we will discuss the definition of “ordinary” or “invisible” autism in a psychoanalytic structural model, as a possible epistemological orientation for identifying and designing practice with the clinical heterogeneity of autism outside the boundaries of psychiatric ASD.ResultsThe autistic population targeted by the DSM-5 criteria is different from that previously defined by DSM-IV. This leads to two consequences: on the one hand, autistic modes of functioning are not limited to individuals who have been diagnosed with Autism Spectrum Disorders as defined by the DSM-5; thus individuals with autism do not have access to the diagnosis of ASD or are given other diagnoses. The alternative diagnoses proposed by the DSM-5 that attempt to correct this diagnostic exclusion — such as Social (Pragmatic) Communication Disorder — are unsatisfactory. Therefore, there is an entire segment of the autistic population that has subclinical, non-prototypic autistic manifestations or more subtle phenomena discernible in the broader autistic phenotype or sub-threshold autism spectrum that does not have access to the ASD diagnosis and raises differential diagnostic issues. On the other hand, it appears that the autism spectrum brings together extremely different entities and false positives such as schizophrenia and schizophrenic spectrum personality disorders under one diagnostic rubric. Then, the differential problem appears central: both at the theoretical level and in diagnostic practices. The recognition of these limits should encourage us to promote research and clinical applications on this subject. One solution that we envisage is to be found in an extension of Maleval's structural psychoanalytical model: we propose the notion of “ordinary autism” — an echo of ordinary psychosis — to define attenuated or compensated non-prototypical autistic phenotypes, increasingly frequent and with fewer “extraordinary” phenomenological expressions than the classic cases of autism which now call into question the relationship between the normal and the pathological.Discussion“Ordinary autism” seems to offer clinicians the opportunity to formalize the new contemporary and extensive clinical reality of autism. This term situates itself within a theoretical model whose current and future developments might help us respond to clinical and diagnostic issues, but also to therapeutic and societal ones. We propose to continue on the path of the operationalization of these theoretical models in order to identify autistic structural constants that could be found throughout the “ordinary” clinic of autism and could serve as differentiating tools for diagnosis as well as a support in developing and refining therapeutic practices.ConclusionWe conclude that there is an urgent need to conceive of “ordinary autism” to provide us with reference points to respond to new clinical issues, but also to reintroduce respect for the autistic person in his or her subjectivity to the center of our therapeutic practices.  相似文献   
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Background Although statins have been shown to be beneficial in the management of hyperlipidemia and the reduction of cardiovascular morbidity and mortality, rates of major cardiovascular events remain high despite their use. Inhibition of the acyl coenzyme A: cholesterol acyltransferase (ACAT) enzyme in the arterial wall may prevent excess accumulation of cholesteryl esters in macrophages. In addition to ACAT inhibitor monotherapy, combination of a statin with an ACAT inhibitor may be a promising approach to further prevent the progression of atherosclerosis. Methods This report describes the design and methodologic features of a double-blind, randomized, placebo-controlled trial to assess the effect of the ACAT inhibitor avasimibe at 50-, 250-, and 750-mg daily dosages on the progression of coronary atherosclerosis as assessed by intravascular ultrasound (IVUS). All patients receive background lipid-lowering therapy when necessary. The study population consists of patients with at least one 20% to 50% diameter stenosis in a coronary artery with a reference diameter of ≥2.5 mm. IVUS and coronary angiography are performed at baseline and repeated at 24 months. The primary study end point is the change from baseline in plaque volume in a 30-mm segment of the coronary artery assessed by 3-dimensional IVUS. Several other IVUS and angiographic end points are measured. Conclusions The Avasimibe and Progression of coronary Lesions assessed by intravascular UltraSound (A-PLUS) trial is among the first large imaging trials to use IVUS as a primary end point and assesses the effects of the ACAT inhibitor avasimibe on atherosclerosis progression. (Am Heart J 2002;144:589-96.)  相似文献   
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