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61.
Z. Oláh S. Komoly N. Nagashima F. Joó U. R. Rapp W. B. Anderson 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1991,83(2):403-410
Summary In this report we describe changes in the intracellular redistribution of raf serine/threonine protein kinase (product of the raf proto-oncogene family) in hippocampal neurons following cerebral ischemia in Mongolian gerbils. For immunohistochemical localization studies polyclonal antisera specific for each of the A, B, and Raf-1 isotypes of raf, as well as a pan-raf antisera, were employed. Of these, only sera recognizing B-raf, as well as the general v-raf (raised against the conserved C-terminal region) were positive, indicating that B-raf is the major isotype in this neuronal region. Three different ischemie models were used (repeated 3 times for two min and single 5 or 15 min occlusions, of the common carotid arteries) to demonstrate that ischemie insult causes redistribution of raf protein kinase into the cell nucleus of hippocampal neurons. Increased amounts of raf protein in the nuclei of pyramidal cells following ischemia was confirmed by Western blot analysis of isolated nuclear fractionations. Moreover, an elevation in the level of nuclear raf protein also was detected in the contralateral (i.e. non-occluded hemisphere) neurons of CA1 and CA3 subfields 4 days after the ischemie insult indicating a possible transsynaptic increase in the amount of raf protein along with redistribution. The intranuclear translocation of the immunoreactive material started from the perinucleolar rim and with time extended throughout the nucleus. Enhanced levels and altered redistribution of the raf polypeptide in the nuclei of pyramidal cells of the CA3 subfleld appears to be reversible and returns to the normal level 12 days following the ischemic insult. In addition to triggering the above changes in the intracellular redistribution of raf, ischemie insult also caused an increase in the level of B-raf protein in reactive astrocytes. 相似文献
62.
Distinct Leishmania braziliensis isolates induce different paces of chemokine expression patterns 总被引:1,自引:0,他引:1 下载免费PDF全文
Teixeira MJ Fernandes JD Teixeira CR Andrade BB Pompeu ML Santana da Silva J Brodskyn CI Barral-Netto M Barral A 《Infection and immunity》2005,73(2):1191-1195
Inflammatory events during Leishmania braziliensis infection in mice were investigated. Large lesions were directly correlated with the inflammatory reaction but not with parasite burden. Different L. braziliensis strains induce different paces of chemokine expression patterns, leading to diverse cell recruitment and differential inflammatory responses. 相似文献
63.
Analysis of the immune response to Mycobacterium avium subsp. paratuberculosis in experimentally infected calves 下载免费PDF全文
Koo HC Park YH Hamilton MJ Barrington GM Davies CJ Kim JB Dahl JL Waters WR Davis WC 《Infection and immunity》2004,72(12):6870-6883
Johne's disease of cattle is widespread and causes significant economic loss to producers. Control has been hindered by limited understanding of the immune response to the causative agent, Mycobacterium avium subsp. paratuberculosis, and lack of an effective vaccine and sensitive specific diagnostic assays. The present study was conducted to gain insight into factors affecting the immune response to M. avium subsp. paratuberculosis. A persistent proliferative response to M. avium subsp. paratuberculosis purified protein derivative and soluble M. avium subsp. paratuberculosis antigens was detected in orally infected neonatal calves 6 months postinfection (p.i.) by flow cytometry (FC). CD4(+) T cells with a memory phenotype (CD45R0(+)) expressing CD25 and CD26 were the predominant cell type responding to antigens. Few CD8(+) T cells proliferated in response to antigens until 18 months p.i. gammadelta T cells did not appear to respond to antigen until 18 months p.i. The majority of WC1(+) CD2(-) and a few WC1(-) CD2(+) gammadelta T cells expressed CD25 at time zero. By 18 months, however, subsets of gammadelta T cells from both control and infected animals showed an increase in expression of CD25, ACT2, and CD26 in the presence of the antigens. Two populations of CD3(-) non-T non-B null cells, CD2(+) and CD2(-), proliferated in cell cultures from some control and infected animals during the study, with and without antigen. The studies clearly show multicolor FC offers a consistent reliable way to monitor the evolution and changes in the immune response to M. avium subsp. paratuberculosis that occur during disease progression. 相似文献
64.
Kazuto Yamada Takaaki Tanaka Masahiko Mori Airo Tsubura Sotokichi Morii Mikio Tsubone Chiaki Ando Jo Hilgers 《Virchows Archiv : an international journal of pathology》1989,415(6):509-521
Summary MAM-3 and MAM-6 antigens of human milk fat globule membrane were detected immunohistochemically in 93 cases of salivary gland tumours as well as in normal glands. The antigens were visualized in 10% formalin-fixed paraffin sections. MAM-3 (MoAbs 115G3, 67D11) antigen was distributed in intercalated and striated duct cells of the normal salivary glands, and in luminal tumour cells and squamous metaplastic cells of pleomorphic adenomas. In pleomorphic adenomas the frequency of positive staining with MoAb 67D11 (54/67; 80.6%) was higher than that with MoAb 115G3 (36/67; 53.7%). MAM-6 (MoAbs 115D8, 115F5) antigen was expressed in luminal and lateral borders of serous acinar cells and ductal of the normal glands, and also in luminal borders of tubulo-ductal and glandular structures of salivary gland tumours. Ductal basal cells were characterized by existence of positive staining for MAM-6 antigen, in adenolymphomas MAM-6 antigen was restricted to the basal tumour cells. Some mucous cells of mucoepidermoid tumours were stained specifically with MoAb 115G3, and epidermoid cells of mucoepidermoid carcinomas manifested MAM-6 antigen staining. Immunohistochemical localization of MAM-6 antigen resembled that of epithelial membrane antigen (EMA) detected with MoAb. 相似文献
65.
In the present study, serotonin (5-HT) responses of hippocampal pyramidal cornu ammonis 1 (CA1) neurons were studied in rats subjected twice daily for 21 days to unpredictable stressors. In hippocampal tissue from thus stressed rats mRNA expression of the 5-HT(1A) receptor and mineralo- as well as glucocorticoid receptors were examined with in situ hybridization. On average, stressed rats displayed increased adrenal weight and attenuated body weight gain compared with controls, supporting that the animals had experienced increased corticosterone levels due to the stress exposure. One day after the last stressor, under conditions that corticosterone levels were low (predominant mineralocorticoid receptor activation), the 5-HT(1A) receptor mediated hyperpolarization of CA1 neurons in response to 10 microM 5-HT was significantly reduced compared with controls. Basal membrane properties of CA1 cells in stressed rats were comparable to those of controls. The 5-HT(1A) receptor mRNA expression was not changed after chronic stress exposure, in any of the hippocampal areas. A small but significant increase in mineralocorticoid receptor mRNA expression was observed after stress in the dentate gyrus, while glucocorticoid receptor expression was unchanged. The data indicate that unpredictable stress exposure for 3 weeks results in suppression of 5-HT(1A) receptor-mediated responses, possibly due to posttranslational modification of the receptor. 相似文献
66.
Genetic relationship between Streptococcus pneumoniae isolates from nasopharyngeal and cerebrospinal fluid of two infants with Pneumococcal Meningitis 下载免费PDF全文
de Andrade AL Pimenta FC Brandileone MC Laval CA Guerra ML de Andrade JG Di Fabio JL 《Journal of clinical microbiology》2003,41(8):3970-3972
The molecular epidemiology of Streptococcus pneumoniae isolates from carriage and cerebrospinal fluid (CSF) concurrently recovered from the same individual has not yet been reported. By using pulsed-field gel electrophoresis, we demonstrated the genetic linkage among strains from CSF and nasopharynges of two children with pneumococcal meningitis. 相似文献
67.
Performance of a commercial, type-specific enzyme-linked immunosorbent assay for detection of herpes simplex virus type 2-specific antibodies in Ugandans 下载免费PDF全文
Laeyendecker O Henson C Gray RH Nguyen RH Horne BJ Wawer MJ Serwadda D Kiwanuka N Morrow RA Hogrefe W Quinn TC 《Journal of clinical microbiology》2004,42(4):1794-1796
Two hundred forty-eight human immunodeficiency virus (HIV)-positive and 496 HIV-negative subjects in Uganda were tested by HerpeSelect herpes simplex virus type 2 enzyme-linked immunosorbent assay (ELISA) and Western blotting to optimize the ELISA for use in this population. A higher index cutoff value was required for optimal sensitivity and specificity, and overall performance of the assay was not affected by HIV status. 相似文献
68.
Helicobacter hepaticus hydrogenase mutants are deficient in hydrogen-supported amino acid uptake and in causing liver lesions in A/J mice 总被引:1,自引:0,他引:1 下载免费PDF全文
Helicobacter hepaticus, a causative agent of chronic hepatitis and hepatocellular carcinoma in mice, expresses a nickel-containing hydrogen-oxidizing hydrogenase enzyme. Growth of a hyaB gene-targeted mutant was unaffected by the presence of hydrogen, unlike the wild-type strain, which showed an enhanced growth rate when supplied with H(2). Hydrogenase activities in H. hepaticus were constitutive and not dependent on the inclusion of H(2) during growth. Addition of nickel during growth significantly stimulated both urease (for wild-type and hyaB) and hydrogenase (for wild-type) activities. In a 5-h period, the extent of (14)C-labeled amino acid uptake by the wild type was markedly enhanced in the presence of hydrogen and was >5-fold greater than that of the hyaB mutant strain. In the presence of H(2), the short-term whole-cell amino acid uptake V(max) of the parent strain was about 2.2-fold greater than for the mutant, but the half-saturation affinity for amino acid transport was the same for the parent and mutant strain. The liver- and cecum-colonizing abilities of the strains was estimated by real-time PCR quantitation of the H. hepaticus-specific cytolethal distending toxin gene and showed similar animal colonization for the hyaB mutant and the wild type. However, at 21 weeks postinoculation, the livers from mice inoculated with wild type exhibited moderate lobular lymphoplasmacytic hepatitis with hepatocytic coagulative necrosis, but the hydrogenase mutants exhibited no histological evidence of lobular inflammation or necrosis. 相似文献
69.
George Capone Mary Stephens Stephanie Santoro Brian Chicoine Peter Bulova Moya Peterson Joan Jasien Anna Jo Smith Down Syndrome Medical Interest Group Adult Health Workgroup 《American journal of medical genetics. Part A》2020,182(7):1832-1845
Adults with Down syndrome (DS) represent a unique population who are in need of clinical guidelines to address their medical care. Many of these conditions are of public health importance with the potential to develop screening recommendations to improve clinical care for this population. Our workgroup previously identified and prioritized co‐occurring medical conditions in adults with DS. In this study, we again performed detailed literature searches on an additional six medical conditions of clinical importance. A series of key questions (KQ) were formulated a priori to guide the literature search strategy. Our KQs focused on disease prevalence, severity, risk‐factors, methodologies for screening/evaluation, impact on morbidity, and potential costs/benefits. The available evidence was extracted, evaluated and graded on quality. The number of participants and the design of clinical studies varied by condition and were often inadequate for answering most of the KQ. Based upon our review, we provide a summary of the findings on hip dysplasia, menopause, acquired cardiac valve disease, type 2 diabetes mellitus, hematologic disorders, and dysphagia. Minimal evidence demonstrates significant gaps in our clinical knowledge that compromises clinical decision‐making and management of these medically complex individuals. The creation of evidence‐based clinical guidance for this population will not be possible until these gaps are addressed. 相似文献
70.