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991.
Proapoptotic Bak is sequestered by Mcl-1 and Bcl-xL, but not Bcl-2, until displaced by BH3-only proteins 总被引:30,自引:0,他引:30
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Willis SN Chen L Dewson G Wei A Naik E Fletcher JI Adams JM Huang DC 《Genes & development》2005,19(11):1294-1305
Commitment of cells to apoptosis is governed largely by the interaction between members of the Bcl-2 protein family. Its three subfamilies have distinct roles: The BH3-only proteins trigger apoptosis by binding via their BH3 domain to prosurvival relatives, while the proapoptotic Bax and Bak have an essential downstream role involving permeabilization of organellar membranes and induction of caspase activation. We have investigated the regulation of Bak and find that, in healthy cells, Bak associates with Mcl-1 and Bcl-x(L) but surprisingly not Bcl-2, Bcl-w, or A1. These interactions require the Bak BH3 domain, which is also necessary for Bak dimerization and killing activity. When cytotoxic signals activate BH3-only proteins that can engage both Mcl-1 and Bcl-x(L) (such as Noxa plus Bad), Bak is displaced and induces cell death. Accordingly, the BH3-only protein Noxa could bind to Mcl-1, displace Bak, and promote Mcl-1 degradation, but Bak-mediated cell death also required neutralization of Bcl-x(L) by other BH3-only proteins. The results indicate that Bak is held in check solely by Mcl-1 and Bcl-x(L) and induces apoptosis only if freed from both. The finding that different prosurvival proteins have selective roles has notable implications for the design of anti-cancer drugs that target the Bcl-2 family. 相似文献
992.
Assessing the effect of visual and tactile distractors on the perception of auditory apparent motion
Sanabria D Soto-Faraco S Spence C 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,166(3-4):548-558
In this study we investigated the effect of the directional congruency of tactile, visual, or bimodal visuotactile apparent motion distractors on the perception of auditory apparent motion. Participants had to judge the direction in which an auditory apparent motion stream moved (left-to-right or right-to-left) while trying to ignore one of a range of distractor stimuli, including unimodal tactile or visual, bimodal visuotactile, and crossmodal (i.e., composed of one visual and one tactile stimulus) distractors. Significant crossmodal dynamic capture effects (i.e., better performance when the target and distractor stimuli moved in the same direction rather than in opposite directions) were demonstrated in all conditions. Bimodal distractors elicited more crossmodal dynamic capture than unimodal distractors, thus providing the first empirical demonstration of the effect of information presented simultaneously in two irrelevant sensory modalities on the perception of motion in a third (target) sensory modality. The results of a second experiment demonstrated that the capture effect reported in the crossmodal distractor condition was most probably attributable to the combined effect of the individual static distractors (i.e., to ventriloquism) rather than to any emergent property of crossmodal apparent motion. 相似文献
993.
Hematopoietic stem cell transplant (HSCT) for autoimmune diseases has been recognized as a potential treatment for patients who have failed conventional therapy. Autologous (self) donor cells have been preferred over allogeneic (HLA-matched) cells for rescue after high dose immunotherapy, given the previous higher rates of mortality, graft versus host disease (GVHD), and the need for more intense myeloablation associated with the latter. The European Group for bone Marrow Transplantation in Basel Switzerland (EBMT) and various groups within the US funded by the NIH (including the Autologous Blood and Marrow Transplant Registry (ABMTR)) have been pivotal in maintaining registries on patients transplanted as well as promoting homogeneity for future studies including Rheumatoid Arthritis (RA), Systemic Lupus Erythematosus (SLE) and Systemic Sclerosis (SSc). Although, patients transplanted for RA show initial success, relapse of the disease is common. In many, however, a second positive result can be obtained with the addition of DMARD therapy to which they were previously unresponsive, suggesting a "debulking" of disease by HSCT. SLE patients also have a high rate of success after HSCT, although current mortality rates appear high. Transplant in SSc patients has offered durable responses with improving transplant-related mortality related to careful patient selection. 相似文献
994.
Miksch S Lumsden A Guenther UP Foernzler D Christen-Zäch S Daugherty C Ramesar RK Lebwohl M Hohl D Neldner KH Lindpaintner K Richards RI Struk B 《Human mutation》2005,26(3):235-248
Pseudoxanthoma elasticum (PXE) is a systemic heritable disorder that affects the elastic tissue in the skin, eye, and cardiovascular system. Mutations in the ABCC6 gene cause PXE. We performed a mutation screen in ABCC6 using haplotype analysis in conjunction with direct sequencing to achieve a mutation detection rate of 97%. This screen consisted of 170 PXE chromosomes in 81 families, and detected 59 distinct mutations (32 missense, eight nonsense, and six likely splice-site point mutations; one small insertion; and seven small and five large deletions). Forty-three of these mutations are novel variants, which increases the total number of PXE mutations to 121. While most mutations are rare, three nonsense mutations, a splice donor site mutation, and the large deletion comprising exons 23-29 (c.2996_4208del) were identified as relatively frequent PXE mutations at 26%, 5%, 3.5%, 3%, and 11%, respectively. Chromosomal haplotyping with two proximal and two distal polymorphic markers flanking ABCC6 demonstrated that most chromosomes that carry these relatively frequent PXE mutations have related haplotypes specific for these mutations, which suggests that these chromosomes originate from single founder mutations. The types of mutations found support loss-of-function as the molecular mechanism for the PXE phenotype. In 76 of the 81 families, the affected individuals were either homozygous for the same mutation or compound heterozygous for two mutations. In the remaining five families with one uncovered mutation, affected showed allelic compound heterozygosity for the cosegregating PXE haplotype. This demonstrates pseudo-dominance as the relevant inheritance mechanism, since disease transmission to the next generation always requires one mutant allelic variant from each parent. In contrast to other previous clinical and molecular claims, our results show evidence only for recessive PXE. This has profound consequences for the genetic counseling of families with PXE. 相似文献
995.
The history of doctoral training in psychology is reviewed, with special emphasis on the development of training models for applied psychology. Among applied psychology doctoral programs, most label themselves as being one of the three currently recognized practice areas: clinical, counseling, and school psychology; however, since the 1970s, APA also has accredited "combined" programs. The history of the development of the combined model is traced, including information from the programs themselves about the manner in which each evolved. Recently, new interest in the combined category -or Combined-Integrated (C-I) as these programs wish to become known-has emerged, and an organization representing these programs has formed. The C-I model is described, and the potential that the model may serve as a template for the future of professional training in psychology is discussed. 相似文献
996.
Dezzutti CS Guenthner PC Daniel S Utz U Cabrera T Marshall JH Bianco C Lal RB Cowan EP 《Clinical and diagnostic laboratory immunology》2003,10(4):715-717
A potential public health concern is the reported detection of the human T-lymphotropic virus (HTLV) tax gene in the lymphocytes of up to 11% of a low-risk group of New York City blood donors (NYBD). This study aimed to independently confirm the prevalence of HTLV tax sequences in 293 NYBD. All NYBD tested negative for antibodies to HTLV types 1 and 2 and HTLV Tax. HTLV tax sequences were not detected in the NYBD lymphocytes. These data demonstrate the lack of HTLV-1 tax in this group of NYBD at low risk for HTLV infection. 相似文献
997.
Microsatellite instability and alteration of the expression of hMLH1 and hMSH2 in ovarian clear cell carcinoma 总被引:5,自引:0,他引:5
Cai KQ Albarracin C Rosen D Zhong R Zheng W Luthra R Broaddus R Liu J 《Human pathology》2004,35(5):552-559
Microsatellite instability (MSI) is commonly seen in tumors associated with the hereditary nonpolyposis colorectal cancer syndrome and is caused by defects in the DNA mismatch repair genes. MSI has also been observed in various sporadic cancers, including colorectal, gastric, and endometrial. The role and incidence of MSI in ovarian clear cell carcinoma remain unknown. This study was conducted to evaluate the frequency of MSI in ovarian clear cell carcinomas and to evaluate the sensitivity and specificity of immunohistochemistry in predicting mismatch-repair gene deficiency. A total of 42 ovarian clear cell carcinomas were analyzed for MSI using a panel of 5 microsatellite markers (BAT25, BAT26, D5S346, D2S123, and D17S250). Alterations in the expression of hMLH1 and hMSH2 proteins in these tumors were examined. Of the 42 ovarian clear cell tumors analyzed, 6 demonstrated a high level of MSI (MSI-H), 3 demonstrated a low level of MSI (MSI-L), and the remaining 33 exhibited microsatellite stability (MSS). No correlation was found between MSI level and patient age or tumor stage or size (P >0.05). Loss of expression of either hMLH1 or hMSH2 was observed in 4 of the 6 (67.7%) MSI-H tumors, whereas 34 of the 36 (94.4%) MSI-L or MSS tumors expressed both the hMLH1 and hMSH2 gene products. Our results indicate that MSI-H is involved in the development of a subset of ovarian clear cell carcinomas. A strong correlation exists between alterations in the expression of hMLH1 and hMSH2 and the presence of MSI-H in these tumors. However, immunohistochemical testing alone may miss a small fraction of cases with MSI-H. 相似文献
998.
Karen?J?ShermanEmail author Daniel?C?Cherkin Maureen?T?Connelly Janet?Erro Jacqueline?B?Savetsky Roger?B?Davis David?M?Eisenberg 《BMC complementary and alternative medicine》2004,4(1):9
Background
Although back pain is the most common reason patients use complementary and alternative medical (CAM) therapies, little is known about the willingness of primary care back pain patients to try these therapies. As part of an effort to refine recruitment strategies for clinical trials, we sought to determine if back pain patients are willing to try acupuncture, chiropractic, massage, meditation, and t'ai chi and to learn about their knowledge of, experience with, and perceptions about each of these therapies. 相似文献999.
Gaide O Favier B Legler DF Bonnet D Brissoni B Valitutti S Bron C Tschopp J Thome M 《Nature immunology》2002,3(9):836-843
CARMA1 is a lymphocyte-specific member of the membrane-associated guanylate kinase (MAGUK) family of scaffolding proteins, which coordinate signaling pathways emanating from the plasma membrane. CARMA1 interacts with Bcl10 via its caspase-recruitment domain (CARD). Here we investigated the role of CARMA1 in T cell activation and found that T cell receptor (TCR) stimulation induced a physical association of CARMA1 with the TCR and Bcl10. We found that CARMA1 was constitutively associated with lipid rafts, whereas cytoplasmic Bcl10 translocated into lipid rafts upon TCR engagement. A CARMA1 mutant, defective for Bcl10 binding, had a dominant-negative (DN) effect on TCR-induced NF-kappa B activation and IL-2 production and on the c-Jun NH(2)-terminal kinase (Jnk) pathway when the TCR was coengaged with CD28. Together, our data show that CARMA1 is a critical lipid raft-associated regulator of TCR-induced NF-kappa B activation and CD28 costimulation-dependent Jnk activation. 相似文献
1000.
Türker KS Yeo PL Gandevia SC 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,165(1):37-43
As visual guidance of facial movements is impossible, accurate movements for speech and mastication require an established body image that is formed via the information from mechanoreceptors in the skin, mucosa, periodontium, and proprioceptors in the facial and masticatory muscles and in the jaw joints. In this study we aimed to investigate how the acute deafferentation of lips and teeth alters the established image of lips, teeth and the thumb. We used a psychophysical method to determine whether the perceived sizes of the upper lip and front teeth change when the sensory input from the lips and front teeth is fully blocked. We also examined the perceived size of the thumb to test for acute interactions between the thumb and facial structures. Local anaesthetic blocking of upper lip and upper front teeth significantly increased the perceived size of the upper lip by as much as 100% (range 21–100%) in ten out of eleven subjects tested (overall mean 52%; p=0.001). The perceived size of the upper teeth also significantly increased by as much as 155% (range 30–155%) in eight of the eleven subjects during anaesthesia (overall mean 41%; p=0.035). When the region of anaesthesia was increased and both upper and lower teeth and lips were anaesthetised, the perceived size of the upper lip again increased, by 53% (p=0.040), but the change in perceived size of the upper front teeth (18%) was not significant (p=0.206). In both studies there was no change in perceived size of the thumb. The results illustrate the labile central interaction between sensory inputs and the importance of feedback from peripheral afferents in generating the subjective facial image. The timing, level, and area of anaesthesia may be important modifiers of these interactions. 相似文献