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The addition of normal mouse serum (NMS) to mouse bone marrow cell cultures was found to stimulate the growth of late erythroid precursors (CFU-E). The stimulating activity was called Erythropoietic Stimulating Cofactor (ESCF) (Blanchet et al 1984). In this article, we report that CFU-Es from foetal liver are not sensitive to serum addition, in contrast to CFU-Es from bone marrow or spleen taken from the same foetuses. When foetal liver cells were co-cultured with irradiated adult bone marrow cells, addition of NMS stimulated the foetal liver CFU-Es, suggesting that ESCF acts via some accessory cells not present (or in too low a frequency) among foetal liver cells. Moreover, NMS should be added at onset of adult bone marrow cell culture to be fully stimulatory. In addition, a very large increase (by a factor of 5 to 7) was observed for CFU-Es from spleen and bone marrow from 6- to 20-d-old newborn mice. This high sensitivity was correlated with a post-natal anaemia. We propose the existence of two different CFU-E population, one stimulated by the accessory cells, the other not, the proportion of which could be modified in response to anaemia. 相似文献
24.
B Croisile B Laurent D Michel D Le Bars L Cinotti F Mauguière 《Revue neurologique》1991,147(3):192-199
The authors report 3 cases of slowly progressive aphasia with different language disturbances: anomia, pure word deafness and Broca's aphasia. All patients were independent in daily life activities. Insight, judgement and overall behaviour were intact. There was no major disturbance of other cognitive functions, but psychometric tests showed mild deficits suggesting widespread involvement. CT scans and magnetic resonance imaging showed focal dilatation of the left sylvian fissure. A positron emission tomographic study showed left perisylvian hypometabolism. A review of the literature yielded an increasing number of cases of this degenerative syndrome affecting dominant hemisphere language areas. Our cases confirm the clinical heterogeneity of degenerative aphasia. Postmortem neuropathological examinations are rare and many causes are found: Pick's disease, Alzheimer's disease or aspecific gliosis. 相似文献
25.
Laurent Garel Josée Dubois Fran?oise Rypens Alain Ouimet Salam Yazbeck 《Journal l'Association canadienne des radiologistes》2004,55(1):39-44
OBJECTIVE: To report on the high incidence of anatomical variants of the origin and course of the internal spermatic vein (ISV) discovered at the time of percutaneous embolization of left varicoceles in a pediatric population. METHODS: We reviewed retrospectively the 65 cases of left varicocele treated by percutaneous embolization (grade II and III) in our institution between 1990 and 2000. The course of the left renal vein (LRV), the origin of the ISV, and the number of ISVs and their pathway were recorded in all cases, according to the B?hren classification. RESULTS: In 37/65 (57%), the ISV was single and arose from a normal LRV (type I). The following variants were encountered: type V--circumaortic LRV 9/65 (14%); type IVb--intrarenal origin of ISV 8/65 (12%); type II--multiple ISV 5/65 (8%); and pelvic collaterals 6/65 (9%). CONCLUSION: Venous anatomical variants are frequently encountered (43%) at the time of left varicocele embolization in children. Such variants often impose some adjustments to the technique of embolization and, at times, hamper the procedure. 相似文献
26.
Hongbo Wang Songyun Li Laurent Givalois & Georges Pelletier 《Journal of neuroendocrinology》1998,10(3):193-198
Recently, an 86-amino acid polypeptide with high affinity for diazepam binding sites, termed diazepam-binding inhibitor (DBI), has been found in the rat brain. DBI, as well as a peptide derived from DBI, the octadecaneuropeptide DBI[33–50] (ODN), interacts with the GABAA receptor complex. To investigate the role of these endogenous ligands for GABAA receptors on prolactin gene expression, we studied the effects of acute intracerebroventricular administration (4 h before sacrifice) of ODN on prolactin mRNA levels in the male rat. Because, in some neuropeptidergic systems, glucocorticoids play a role in the response to ODN, we also studied the influence of adrenal glands and the effect of dexamethasone administration in the response of prolactin gene expression to ODN. ODN injection produced an increase in prolactin mRNA levels. Adrenalectomy performed 5 days before sacrifice resulted in an increase in prolactin gene expression and also potentiated the stimulating effect of ODN. Because castration has been shown to decrease prolactin gene expression in the male rat, we used castrated and adrenalectomized animals to study the role of dexamethasone in the response of lactotrophs to ODN. In these steroid-deprived animals, dexamethasone treatment (for 4 days) decreased prolactin mRNA levels but did not modify the response to ODN. These data indicate that an endogenous neuropeptide interacting with the GABAA receptor complex can stimulate prolactin gene expression and suggest that the adrenal glands may produce factor(s) capable of decreasing prolactin mRNA. On the other hand, it does not appear that glucocorticoid hormones play a role in the effect of ODN on lactotroph activity. 相似文献
27.
Recombination between HLA-A and C and between HLA-B and complement locus C4 in the same individual 总被引:1,自引:0,他引:1
M. Thomsen A. Cambon-Thomsen M. Abbal M. Calot J. Arnaud E. Ohayon 《Tissue antigens》1985,25(2):75-78
In a French family with 2 parents and 5 children a crossing over was found in the HLA region on both of the parental haplotypes of one of the children. The following markers were studied: HLA-A, B, C,DR, DQ(MB), DP(SB), complement allotypes C4 and Bf and glyoxalase I polymorphism. In the third child, the paternal haplotype had a recombination between HLA-A and HLA-C and the maternal haplotype a recombination between HLA-B and complement locus C4. Mixed lymphocyte cultures confirmed the serological findings and non-HLA markers (blood groups and immunoglobulin allotypes) showed no evidence of extrapaternity. The family also demonstrates a probable duplication of the C4B1 gene in one of the paternal haplotypes. 相似文献
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29.
Thomas Barba Romain Fort Vincent Cottin Steeve Provencher Isabelle Durieu Sabine Jardel Arnaud Hot Quitterie Reynaud Jean-Christophe Lega 《Autoimmunity reviews》2019,18(2):113-122
Objective
Interstitial lung disease (ILD) is the most severe complication of idiopathic inflammatory myositis (IIM), resulting in significant increase in morbidity and mortality and for which the best treatment remains controversial. We conducted a meta-analysis to evaluate the efficacy of therapies used for the management of IIM-related ILD.Methods
Studies were selected from MEDLINE up to July 2017. Two investigators independently extracted data on study design, patient characteristics, clinical features, treatment, follow-up and outcomes. Global survival rates and objectively confirmed lung function improvements were extracted as the main outcome for rapidly progressive IIM-related ILD (RP-ILD) and chronic forms of ILD (C-ILD), respectively, and pooled using the weighted mean proportion with fixed or random-effects models in case of significant heterogeneity (I2?>?50%).Results
Twenty-seven studies encompassing 553 patients (male: 30.5%, age: 53.5?±?5.5?years) were included in the meta-analysis. Globally, retrieved studies were of limited methodological quality (no controlled studies and only 2 prospective studies). Dermatomyositis (40%) and anti-tRNA synthetase syndrome (45%) were the most represented IIM subtypes. In C-ILD, functional improvement rates were 89.2% (95%CI 82.5–93.6; 7 studies, n?=?124) for corticosteroids alone, 80.7% (95%CI 49.6–94; 6 studies, n?=?38) for cyclosporine A, 64.1% (95%CI 46.3–78.7; 4 studies, n?=?32) for azathioprine, 86.2% (95%CI 61.5–96; 2 studies, n?=?23) for tacrolimus, 56.4% (95%CI 44–68.0; 8 studies, n?=?71) for cyclophosphamide, and 76.6% (95%CI 50.4–96.0; 2 studies, n?=?20) for rituximab. In RP-ILD, survival rates at 3?months were 51.7% (95%CI 24.2–78.1; 2 studies, n?=?11) for corticosteroids alone, 69.2% (95%CI 55.0–80.5; 8 studies, n?=?146) for cyclosporine A and 72.4% (95%CI 6.4–99.0, 2 studies, n?=?16) for cyclophosphamide.Conclusion
Despite aggressive immunosuppressive therapies, the short-term mortality of RP-ILD remains high. While immunosuppressive therapies are associated with significant functional improvements in most patients with C-ILD, substantial uncertainty remains about the best treatment strategy in the absence of good quality evidence. 相似文献30.
The atheroprotective effect of 17beta-estradiol depends on complex interactions in adaptive immunity 下载免费PDF全文
Elhage R Gourdy P Jawien J Brouchet L Castano C Fievet C Hansson GK Arnal JF Bayard F 《The American journal of pathology》2005,167(1):267-274
Estradiol prevents fatty streak formation in chow-fed atherosclerosis-prone apolipoprotein E (ApoE)-deficient mice. We previously reported that fatty streak development of immunodeficient ApoE(-/-)/recombination activating gene 2 (RAG-2(-/-)) double-deficient mice was insensitive to estradiol. In the present work, we demonstrate that the reconstitution of ApoE(-/-)/RAG-2(-/-) with bone marrow from immunocompetent ApoE(-/-)/RAG-2(+/+) mice restores the protective effect of estradiol on fatty streak constitution. We extended this demonstration to the model of low-density lipoprotein receptor-deficient mice, establishing the obligatory role of mature lymphocytes in this process. We then investigated whether the protective effect of estradiol was mediated by a specific lymphocyte subpopulation by studying the hormonal effect on fatty streak constitution in recently developed models of ApoE(-/-) mice deficient in selective T-lymphocyte subsets (either TCRalphabeta+, CD4+, CD8+, or TCRgammadelta+ lymphocytes) or B lymphocytes. In all these specifically immunodeficient mice, estradiol administration to ovariectomized mice conferred protection as in immunocompetent ApoE(-/-) mice, clearly demonstrating that no single lymphocyte subpopulation was specifically required for this effect. These results point to additional lymphocyte-dependent mechanisms such as modulating the interactions among lymphocytes and between lymphocytes and endothelial and/or antigen-presenting cells. 相似文献