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91.
To assess the importance of B cell control of T cell differentiation, we analyzed the course of the T helper type 1 (T(H)1)-driven disease experimental autoimmune encephalomyelitis in mice with an altered B cell compartment. We found that recovery was dependent on the presence of autoantigen-reactive B cells. B cells from recovered mice produced interleukin 10 (IL-10) in response to autoantigen. With a bone marrow chimeric system, we generated mice in which IL-10 deficiency was restricted to B cells but not T cells. In the absence of IL-10 production by B cells, the pro-inflammatory type 1 immune response persisted and mice did not recover. These data show that B cell-derived IL-10 plays a key role in controlling autoimmunity. 相似文献
92.
93.
David Laurin Eric Spierings Lars T van der Veken Abdelbasset Hamrouni J H Frederik Falkenburg Gerard Souillet Corine Vermeulen Annie Farre Claire Galambrun Dominique Rigal Yves Bertrand Els Goulmy Assia Eljaafari 《Biology of blood and marrow transplantation》2006,12(11):1114-1124
In vitro stimulation of human female T cells with male HLA-identical dendritic cells resulted in the generation of HLA-DQB1*0501/0502-restricted minor histocompatibility H-Y antigen-specific CD4(+) T cell clones. Two clones generated from different HLA-identical pairs were analyzed. Use of HLA-DQ5-expressing female Epstein-Barr virus transformed B lymphoblastoid cell lines transfected with various H-Y genes and loaded with overlapping peptides demonstrated that both T cell clones are specific for a peptide encoded by DDX3Y. Previously, an HLA-DQ5-restricted T cell clone specific for the same peptide was isolated from a patient with graft-versus-host disease. Thus, we compared the T cell receptor (TCR) rearrangements of the 2 in vitro generated T cell clones and the ex vivo isolated T cell clone. All 3 clones shared the same TCRBV5-4* gene segment and 2 of 3 clones also used similar TCR-Valpha segments. Our results suggest that T cells recognizing the HLA-DQ5/DDX3Y T cell epitope might be characterized by a relatively limited TCR-beta repertoire. The differences in the junctional TCR-beta region had no effect on the antigen specificity, but altered the capacity of the TCR to distinguish the HLA-DQ5/DDX3Y complex from its allelic counterpart. The results also demonstrate that in vitro stimulation of T cells with allogeneic HLA-identical dendritic cells may facilitate the characterization of in vivo, potentially relevant HLA class II-restricted minor H epitopes. 相似文献
94.
Ectopic pituitary adenoma (EPA) is rare and, to the authors’ knowledge, its association with peliosis has not yet been described.
The case of a 38-yr-old woman with clinical and biochemical evidence of Cushing’s syndrome is reported. Magnetic resonance
imaging (MRI) disclosed a normal pituitary and a separate mass in the sphenoid sinus. The surgically remove’s hyaline change
in the corticotrophs, indicating exposure to glucocorticoid excess. By histology, the mass in the sphenoid sinus was a congested,
chromophobic, partly basophilic, periodic acid-Schiff (PAS)-positive pituitary adenoma composed of pleomorphic, adrenocorticotropic
hormone (ACTH)-positive, corticotrophs. There was focal immunopositivity for MIB-1 and proliferating cell nuclear antigen
(PCNA). Electron microscopy confirmed the diagnosis of corticotroph adenoma. A striking finding, consistent with the diagnosis
of peliosis, was the presence of multiple large blood-filled spaces lacking an endothelial lining. The capillaries were dilated,
but often appeared empty and the fenestrated endothelium exhibited discontinuities. The cause of peliosis is obscure. It may
be that the venous outflow was impaired in this case leading to capillary dilation, congestion, hyperpermeability, rupture,
and accumulation of blood in extravascular spaces. 相似文献
95.
96.
Adhesion of neutrophils to vascular endothelial cells (ECs), mediated by the interaction of CD11/CD18 and intercellular adhesion molecule-1 (ICAM-1), is often required for neutrophil transmigration across endothelium during most inflammatory responses. Induction of intracellular signaling in neutrophils as a result of adhesion has been recognized for many years. Recent studies demonstrated that neutrophil-endothelial adhesion also activates ECs. Examples of neutrophil adherence-induced changes in ECs include increases in intracellular Ca(2+), production of reactive oxygen species, and actin cytoskeleton changes. These changes result, in part, from ligation of EC adhesion molecules. This review article focuses on the signaling events that occur in ECs during neutrophil adhesion and the role of EC adhesion molecules, particularly ICAM-1, in the initiation of these signaling events in ECs. The evidence to date describing the molecular basis of ICAM-1-induced signaling will be summarized. Finally, the potential physiological roles of these signaling events induced by EC adhesion molecules in mediating neutrophil migration will be addressed. 相似文献
97.
Thomas W. Prior Gail D. Wenger Audrey C. Papp Pamela J. Snyder Mary S. Sedra Claire Bartolo Jay W. Moore W. Edward Highsmith 《Human mutation》1995,5(3):263-268
A new strategy has been developed for rapid haplotype analysis based on an initial multiplex amplification of several polymorphic sites, followed by heteroduplex detection. Heteroduplexes formed between two different alleles are detected because they migrate differently than the corresponding homoduplexes in Hydrolink-MDE gel. This simple, rapid method does not depend on specific sequences such as restriction enzyme sites or CA boxes and does not require the use of isotope. This approach has been tested using commonly occurring polymorphisms spanning the dystrophin gene as a model. We describe the use of the method to assign the carrier status of females in Duchenne muscular dystrophy (DMD) pedigrees. The method may be used for other genetic diseases when mutations are unknown or there are few dinucleotide markers in the gene proximity, and for the identification of haplotype backgrounds of mutant alleles. © 1995 Wiley-Liss, Inc. 相似文献
98.
Viability of partially damaged human embryos after cryopreservation 总被引:10,自引:13,他引:10
Van den Abbeel E; Camus M; Van Waesberghe L; Devroey P; Van Steirteghem AC 《Human reproduction (Oxford, England)》1997,12(9):2006-2010
In our centre, embryos are judged to have survived cryopreservation if at
least half of the initial number of blastomeres remain intact. Therefore
both fully intact and partially damaged embryos are transferred. The aim of
this study was to investigate the viability of partially damaged human
embryos after cryopreservation. We retrospectively analysed the
implantation and in-vivo development of embryos which were either fully
intact or had lost some blastomeres after cryopreservation. Oocytes were
collected following stimulation with the gonadotrophin-releasing hormone
(GnRH)-agonist Buserelin and human menopausal gonadotrophin. Supernumerary
multicellular embryos with not more than 20% of their volume filled with
anucleate fragments were frozen on day 2 or day 3 of the cycle using a slow
cooling procedure with dimethylsulphoxide as the cryoprotectant. Following
slow thawing, 431 fully intact embryos were transferred in 314 embryo
transfer procedures and 488 partially damaged embryos were transferred in
327 such procedures. The percentage of gestational sacs with fetal
heartbeat obtained after transfer of fully intact embryos was almost three
times higher than that after transfer of partially damaged embryos (11.4
versus 3.5%). Forty-five children (birth rate 10% per embryo transfer) were
born after transfer of fully intact embryos and 14 after transfer of
embryos from which some blastomeres had been lost following
cryopreservation. In conclusion, although children have been delivered
after transfer of partially damaged embryos, the aim of a cryopreservation
programme must be to obtain fully intact embryos after thawing.
相似文献
99.
Incidence of severe ovarian hyperstimulation syndrome after GnRH agonist/HMG superovulation for in-vitro fertilization 总被引:1,自引:3,他引:1
J Smitz M Camus P Devroey P Erard A Wisanto A C Van Steirteghem 《Human reproduction (Oxford, England)》1990,5(8):933-937
In 1673 treatment cycles stimulated with buserelin and HMG, for IVF, GIFT or ZIFT, the severe ovarian hyperstimulation syndrome (OHSS) occurred in 10 cycles (0.6%). Eight patients were hyperandrogenic and showed an increased ovarian response to HMG. After replacement of a maximum of three embryos or zygotes, seven women became pregnant. Three women had a multiple gestation. All patients recovered uneventfully with conservative treatment. Support with progesterone or continuation of the agonist during the luteal phase did not prevent OHSS, confirming that the ovulatory HCG dose is the most important factor in inducing this severe complication. Luteal supplementation with HCG and/or HCG production during implantation could exacerbate OHSS. 相似文献
100.
Leucine supplementation improves muscle protein synthesis in elderly men independently of hyperaminoacidaemia 总被引:3,自引:0,他引:3
Isabelle Rieu Michèle Balage Claire Sornet Christophe Giraudet Estelle Pujos Jean Grizard Laurent Mosoni Dominique Dardevet 《The Journal of physiology》2006,575(1):305-315
The present study was designed to assess the effects of dietary leucine supplementation on muscle protein synthesis and whole body protein kinetics in elderly individuals. Twenty healthy male subjects (70 ± 1 years) were studied before and after continuous ingestion of a complete balanced diet supplemented or not with leucine. A primed (3.6 μmol kg−1 ) constant infusion (0.06 μmol kg−1 min−1 ) of l -[1-13 C]phenylalanine was used to determine whole body phenylalanine kinetics as well as fractional synthesis rate (FSR) in the myofibrillar fraction of muscle proteins from vastus lateralis biopsies. Whole body protein kinetics were not affected by leucine supplementation. In contrast, muscle FSR, measured over the 5-h period of feeding, was significantly greater in the volunteers given the leucine-supplemented meals compared with the control group (0.083 ± 0.008 versus 0.053 ± 0.009% h−1 , respectively, P < 0.05). This effect was due only to increased leucine availability because only plasma free leucine concentration significantly differed between the control and leucine-supplemented groups. We conclude that leucine supplementation during feeding improves muscle protein synthesis in the elderly independently of an overall increase of other amino acids. Whether increasing leucine intake in old people may limit muscle protein loss during ageing remains to be determined. 相似文献