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91.
Neural regions essential for writing verbs 总被引:1,自引:0,他引:1
Functional imaging data collected during cognitive tasks show which brain regions are active during those tasks, but do not necessarily indicate which regions are essential for those tasks. Here, in a study of two cases of selectively impaired written naming of verbs after focal brain ischemia, we combined imaging and behavioral testing to unambiguously identify brain regions that are crucial for a specific cognitive process. We used magnetic resonance perfusion imaging to show that the selective impairment in each case was due to hypoperfusion (low blood flow) in left posterior inferior frontal gyrus (PIFG) and precentral gyrus (PrG); the impairment was immediately reversed when blood flow was restored to these regions, indicating that parts of the left frontal lobe are crucial for representing and processing verbs. 相似文献
92.
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
93.
Wessels MW Berger RM Frohn-Mulder IM Roos-Hesselink JW Hoogeboom JJ Mancini GS Bartelings MM Krijger Rd Wladimiroff JW Niermeijer MF Grossfeld P Willems PJ 《American journal of medical genetics. Part A》2005,(2):171-179
Most nonsyndromic congenital heart malformations (CHMs) in humans are multifactorial in origin, although an increasing number of monogenic cases have been reported recently. We describe here four new families with presumed autosomal dominant inheritance of left ventricular outflow tract obstruction (LVOTO), consisting of hypoplastic left heart (HLHS) or left ventricle (HLV), aortic valve stenosis (AS) and bicuspid aortic valve (BAV), hypoplastic aortic arch (HAA), and coarctation of the aorta (CoA). LVOTO in these families shows a wide clinical spectrum with some family members having severe anomalies such as hypoplastic left heart, and others only minor anomalies such as mild aortic valve stenosis. This supports the suggestion that all anomalies of the LVOTO spectrum are developmentally related and can be caused by a single gene defect. 相似文献
94.
Staphylococcal toxin-induced T cell proliferation in atopic eczema correlates with increased use of superantigen-reactive Vbeta-chains in cutaneous lymphocyte-associated antigen (CLA)-positive lymphocytes 总被引:2,自引:0,他引:2 下载免费PDF全文
Staphylococcal superantigens have been implicated in the pathogenesis of atopic dermatitis (AD). This may occur through superantigenic activation of T lymphocytes and their subsequent induction of the skin homing receptor CLA on activated cells. We investigated the proliferative responses of peripheral blood mononuclear cells (PBMC) from 10 patients with an infective exacerbation of AD and six normal controls to the staphylococcal superantigens, staphylococcal enterotoxin A and B (SEA, SEB) and toxic shock syndrome toxin-1 (TSST-1), and the mitogens phytohaemagglutinin (PHA) and concanavalin A (Con A). We also assessed CLA and T cell receptor (TCR) Vbeta-chain expression by immunofluorescence and flow cytometry before and after stimulation. PBMC from AD patients showed two-fold increased proliferation to SEA and SEB (P < 0.01) compared with normals, whereas the response to mitogenic stimulation was identical. Analysis of (TCR) Vbeta-chain expression demonstrated increased use of superantigen-reactive Vbeta families in freshly isolated PBMC in AD patients compared with controls. This pattern of Vbeta-chain expression was only observed in the CLA+ but not the total population of T cells. Furthermore, there was a positive correlation between the enhanced PBMC proliferative response and increased expression of superantigen-reactive Vbeta families in atopic patients. These data support the concept that superantigens are important in the pathogenesis of this common condition, and also provide evidence that the increased use of certain Vbeta families in circulating, CLA+, skin homing lymphocytes is of functional significance. 相似文献
95.
Kennedy J Jackson GC Barker FS Nundlall S Bella J Wright MJ Mortier GR Neas K Thompson E Elles R Briggs MD 《Human mutation》2005,25(6):593-594
Pseudoachondroplasia (PSACH) and some forms of multiple epiphyseal dysplasia (MED) result from mutations in the gene encoding cartilage oligomeric matrix protein (COMP). COMP is a large pentameric glycoprotein found predominantly in the extracellular matrix of cartilage, tendon, and ligament. As a modular protein, it is composed of a coiled-coil domain, four type II (T2) repeats, eight type III (T3) repeats, and a large globular C-terminal domain (CTD). The majority (>85%) of COMP mutations causing PSACH or MED are found in the exons encoding the T3 repeats, and the disease mechanism has been characterised in detail. Much less is known about disease-causing mutations in the CTD; in 10 years only seven mutations have been identified. In this study, we describe eight novel and two recurrent mutations that we have recently identified in patients with PSACH or MED. Interestingly, these mutations result in a spectrum of disease, ranging from mild MED to severe PSACH. Mapping of all known COMP CTD mutations on a three-dimensional model of the C-terminal domain shows that the CTD mutations cluster in two distinct regions. These regions are probably important in stabilising the T3-CTD structure and mediating intra- or intermolecular interactions. 相似文献
96.
Antigen presentation by macrophages is enhanced by the uptake of necrotic, but not apoptotic, cells 总被引:8,自引:0,他引:8
Barker RN Erwig LP Hill KS Devine A Pearce WP Rees AJ 《Clinical and experimental immunology》2002,127(2):220-225
The aim of this study was to determine whether phagocytosis of necrotic or apoptotic cells affects antigen presentation by murine bone marrow-derived macrophages. After uptake of necrotic neutrophils, macrophages were able to stimulate significantly higher T cell proliferation in vitro against both the recall antigen albumin and the mitogen concanavalin A. No such effect was seen following phagocytosis of apoptotic neutrophils. Flow cytometry revealed that, within 4h of ingestion, macrophages that had taken up the necrotic cells expressed higher levels of CD40 than those that had phagocytosed apoptotic cells. Macrophage cultures pulsed with apoptotic, but not necrotic, neutrophils contained higher levels of transforming growth factor beta1, but lower concentrations of tumour necrosis factor alpha, compared to untreated controls. Our interpretation of these results is that macrophages that have taken up necrotic neutrophils co-stimulate T cells with greater efficiency due to rapid CD40 up-regulation, whereas those that have ingested apoptotic cells are not only ineffective in co-stimulation, but also secrete inhibitory cytokine. 相似文献
97.
98.
The possibility of interfering with the normal function of tick hemolymph using antihemolymph antibodies taken in with the bloodmeal, was investigated. Cell free hemolymph from repleteAmblyomma americanum andDermacentor variabilis ticks was used to immunize rabbits. Immunized rabbits developed high antihemolymph antibody titers (ca. 105) and had no ill side effects. Rabbits were simultaneously infested with larvae, nymphs, and adult ticks. The biological performance of ticks fed on immunized rabbits was virtually identical to that of ticks fed on nonimmunized rabbits. Usually, the mean engorgement weights of nymphs and females and the weights of the egg masses of both species were slightly higher for ticks fed on the nonimmunized rabbits but differences were not significant (P>0.05) due to a large standard deviation. The possibility of deactivating a single hemolymph component with specific antibodies is discussed.Journal article 4979 of the Agricultural Experiment Station, Oklahoma State University, Stillwater, OK, USA 相似文献
99.
Zusammenfassung Atemphysiologische Untersuchungen an 19 Patienten mit Ventilationsstörungen der Lunge mit dem Atmungsanalepticum Micoren ergeben eine Ventilationssteigerung um 60% des Ausgangswertes, eine Abnahme der arteriellen CO2-Spannung und eine Zunahme des Blut-pH, somit eine ventilationsbedingte Verschiebung der Blutgase in Richtung einer relativen respiratorischen Alkalose. Im Mittelpunkt der Untersuchung steht die Frage einer über die Atmungserregung hinaus bei der respiratorischen Acidose und Atemdepression erzielbaren Erregbarkeitsänderung der Zentren. Im Gegensatz zu Patienten ohne respiratorische Acidose läßt sich bei Kranken mit respiratorischer Acidose eine Steigerung der Erregbarkeit auf CO2-Reiz und eine wahrscheinlich begrenzte Verzögerung der unter O2-Atmung drohenden zentralen Depression nachweisen. Indikationen und klinische Gesichtspunkte einer medikamentösen Atmungserregung werden unter besonderer Berücksichtigung der respiratorischen Acidose besprochen.Mit freundlicher Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
100.
Joosen Margot C. W. Lugtenberg Marjolein Arends Iris van Gestel Hanneke J. A. W. M. Schaapveld Benedikte Terluin Berend van Weeghel Jaap van der Klink Jac J. L. Brouwers Evelien P. M. 《Journal of occupational rehabilitation》2022,32(2):272-283
Journal of Occupational Rehabilitation - Purpose Although common mental disorders (CMDs) highly impact individuals and society, a knowledge gap exists on how sickness absence can be prevented in... 相似文献