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991.
Rodrigo-Angulo ML Rodríguez-Veiga E Reinoso-Suárez F 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,160(3):334-343
The ventral part of the cat oral pontine reticular nucleus (vRPO) is the site in which microinjections of small dose and volume of cholinergic agonists produce long-lasting rapid eye movement sleep with short latency. The present study determined the precise location and proportions of the cholinergic brainstem neuronal population that projects to the vRPO using a double-labeling method that combines the neuronal tracer horseradish peroxidase–wheat germ agglutinin with choline acetyltransferase immunocytochemistry in cats. Our results show that 88.9% of the double-labeled neurons in the brainstem were located, noticeably bilaterally, in the cholinergic structures of the pontine tegmentum. These neurons occupied not only the pedunculopontine and laterodorsal tegmental nuclei, which have been described to project to other pontine tegmentum structures, but also the locus ceruleus complex principally the locus ceruleus and peri-, and the parabrachial nuclei. Most double-labeled neurons were found in the pedunculopontine tegmental nucleus and locus ceruleus complex and, much less abundantly, in the laterodorsal tegmental nucleus and the parabrachial nuclei. The proportions of these neurons among all choline acetyltransferase positive neurons within each structure were highest in the locus ceruleus complex, followed in descending order by the pedunculopontine and laterodorsal tegmental nuclei and then, the parabrachial nuclei. The remaining 11.1% of double-labeled neurons were found bilaterally in other cholinergic brainstem structures: around the oculomotor, facial and masticatory nuclei, the caudal pontine tegmentum and the praepositus hypoglossi nucleus. The disperse origins of the cholinergic neurons projecting to the vRPO, in addition to the abundant noncholinergic afferents to this nucleus may indicate that cholinergic stimulation is not the only or even the most decisive event in the generation of REM sleep. 相似文献
992.
Retinoic acid (RA) is a potent regulator of morphogenesis, growth and cell differentiation. Incubation with RA causes arrest of proliferation and neurite extension in SH-SY5Y cells, a neuroblastoma cell line of human origin. In these cells, RA regulates the expression of the β-amyloid precursor protein. The retinoid increases the levels of intracellular and secreted forms of APP (amyloid precursor protein), APP–mRNA levels and the activity of the APP promoter in transient transfection studies. These responses require long periods of exposition to the ligand, thus suggesting a nondirect effect of the RA receptors on the APP gene. Also in these cells, RA induces the expression of TrkB, the tyrosine kinase receptor for brain-derived neurotrophic factor (BDNF), and 4 days of pretreatment with retinoic acid confers BDNF responsiveness to the APP promoter. 相似文献
993.
The immunogenicity of different preparations of an oral inactivated enterotoxigenic Escherichia coli (ETEC) vaccine was evaluated in Swedish volunteers previously unexposed to ETEC infection. The vaccine preparations consisted of recombinant cholera toxin B subunit (CTB) and various amounts of formalin-killed whole bacteria expressing the most prevalent colonization factor antigens (CFAs). Significant immunoglobulin A (IgA) antibody-secreting cell (ASC) responses against CTB and the various CFA components were seen in a majority of volunteers after two doses of ETEC vaccine independent of the vaccine lot given. The IgA ASC responses against CTB were significantly higher after the second than after the first immunization, whereas the CFA-specific IgA ASC responses were almost comparable after the first and second doses of ETEC vaccine. Two immunizations with one-third of a full dose of CFA-ETEC bacteria induced lower frequencies of IgA ASC responses against all the different CFAs than two full vaccine doses, i.e., 63 versus 80% for CFA/I, 56 versus 70% for CS1, 31 versus 65% for CS2, and 56 versus 75% for CS4. The proportion of vaccinees responding with rises in the titer of serum IgA antibody against the various CFA antigens was also lower after immunization with the reduced dose of CFA-ETEC bacteria. These findings suggest that measurements of circulating IgA ASCs can be used not only for qualitative but also for quantitative assessments of the immunogenicity of individual fimbrial antigens in various preparations of ETEC vaccine. 相似文献
994.
Genuardi M Carrara S Anti M Ponz de Leòn M Viel A 《European journal of human genetics : EJHG》1999,7(7):778-782
To determine the role played by MLH1 and MSH2 missense variants in cancer susceptibility, we have investigated the following genetic and biological characteristics associated with six MLH1 and four MSH2 missense changes identified in Italian hereditary nonpolyposis colorectal cancer (HNPCC) families: co-segregation with disease phenotype and/or bonafide pathogenetic mutations; presence of the variant in healthy control subjects; evolutionary conservation of the involved aminoacid and type of aminoacid change; and presence/absence of microsatellite instability (MSI) in tumour DNA. Overall, nine variants did not fulfil > or = 2 pathogenicity criteria. MSI was investigated in tumour samples from carriers of nine different missense mutations. Only 3/9 variants were associated with MSI in tumour DNA. In addition, four variants were not present in affected pedigree members, and five variants were observed in the control population. Based upon these results, we conclude that most MLH1 and MSH2 missense changes are unlikely to act as major causative factors in colorectal cancer susceptibility and development. 相似文献
995.
F. Gamboa J. M. Manterola J. Lonca L. Matas P. J. Cardona E. Padilla B. Viñado J. Domínguez A. Hernández V. Ausina 《European journal of clinical microbiology & infectious diseases》1998,17(3):151-157
Two commercial systems for the amplification and detection ofMycobacterium tuberculosis directly from respiratory samples were compared. The Roche Cobas Amplicor MTB Test and the Roche manual Amplicor MTB Test (Roche Diagnostic Systems, USA) were applied to 755 decontaminated respiratory specimens collected from 470 patients. Results were compared with those of acid-fast staining and culture. A total of 251 specimens were collected from 156 patients diagnosed with pulmonary tuberculosis, including 28 specimens corresponding to 13 patients that were receiving antituberculous treatment. Given the overall positivity rate of 33.2% (251/755), the sensitivity, specificity, and positive and negative predictive values were 92.4, 100, 100, and 96.5%, respectively, for the Cobas Amplicor MTB Test and 90.8, 100, 100, and 95.8%, respectively, for the Amplicor MTB Test. For 204 (81.3%) smear positive specimens and 47 (19.7%) smear negative specimens, the sensitivity values were 100 and 59.6%, respectively, for the Cobas Amplicor MTB Test and 100 and 51%, respectively, for the Amplicor MTB Test. There were no statistically significant differences in sensitivity or specificity between the two assays and culture (p>0.05). The overall results of both assays were concordant for 99.5% of the samples. It is concluded that although both nucleic acid amplification methods are rapid and specific for the detection ofMycobacterium tuberculosis complex in respiratory specimens, the Cobas Amplicor MTB Test appears to be slightly more sensitive than the Amplicor MTB Test when smear negative specimens are investigated. 相似文献
996.
M. Deckert-Schlüter Josef Marek Michael Šetlík Jana Marková E. Pakos Robert Fischer Otmar D. Wiestler 《Virchows Archiv : an international journal of pathology》1998,432(5):477-481
A 62-year-old woman presented with loss of memory and a mild hemiparesis. Neuroradiology demonstrated a left frontoparietal
tumour. Biopsy specimens of this lesion revealed intracerebral Hodgkin’s lymphoma, a diagnosis supported by immunohistochemical
reactions of the tumour cells for the CD30 antigen. Additional cell cycle studies revealed a high proliferative activity of
the tumour cells in association with absence of apoptosis. There was no evidence that overexpression of bcl-2 or Epstein-Barr
virus infection was involved in the pathogenesis of this neoplasm. Lymphomas in the lung were detected 3 months later. Following
neurosurgical excision, radiotherapy, and chemotherapy, the patient had no evidence of Hodgkin’s disease after 13 months of
follow-up.
Received: 8 October 1997 / Accepted: 8 December 1997 相似文献
997.
E. Bouza C. Martín-Scapa J. C. L. Bernaldo de Quirós D. Martínez-Hernández J. Menarguez J. Gómez-Rodrigo J. Cosín M. J. Sagues-Cifuentes 《European journal of clinical microbiology & infectious diseases》1988,7(6):785-788
A total of 67 cases of tuberculosis was diagnosed in the first 100 cases of AIDS, diagnosed according to the former CDC criteria, at a hospital in Madrid, Spain. This is the highest known prevalence of tuberculosis in AIDS patients both within and outside Spain. The clinical manifestations of tuberculosis were very variable and atypical. The rate of isolation ofMycobacterium tuberculosis from blood was particularly high: of 25 patients in whom blood cultures were performed, 16 were positive. In a third of the patients with proven mycobacteremia, blood was the first or the only positive specimen. In general, therapy resulted in rapid clinical improvement, but in some cases mycobacteria were isolated from clinical or necroscopy specimens months after what was considered adequate therapy. 相似文献
998.
Pia Bjrck Carina Elenstrm-Magnusson Anders Rosn Eva Severinson Staffan Paulie 《European journal of immunology》1993,23(8):1771-1775
We have previously found that interleukin-4 and CD40 monoclonal antibodies (mAb) are strong potentiatiors of homotypic B cell aggregation which is dependent on LFA-1. We show here that CD23 mAb were also able to inhibit aggregation to a similar extent as LFA-1 antibodies. This inhibition was restricted to the MHM6 epitope of CD23 and antibodies to other epitopes [Epstein-Barr virus (EBV) CS-1, EBV CS-2, EBV CS-5 and mAb 25] or occupation of the Fc-binding site by IgE had no or a slightly enhancing effect on aggregation. When testing two antibodies to CD21, the recently defined ligand for CD23, one of these (BU32) was found to be inhibitory whereas the other (THB5) had no effect. By combining antibodies to LFA-1 and CD23, aggregation was often completely inhibited. These data suggest that LFA-1/ICAM-1 and CD23/CD21 are the major molecules involved in homotypic aggregation of human B cells. 相似文献
999.
A panel of four microcell hybrids representing different sites of insertion of the exogeneous neogene into mouse chromosome 17 has been constructed. These constructions were based on a cotransfer of mouse chromosome 17 and neomycin resistance generated in a stepwise procedure involving (1) random insertion of the neogene into a primary cell hybrid containing mouse chromosome 17 in a hamster cell background, (2) microcell-mediated chromosome transfer (MMCT) to segregate mouse and hamster chromosomes, and (3) identification of the mouse chromosome containing cells using a novel cell dotting procedure for mass screening at the cell colony level by molecular hybridization. Using this panel of four microcell hybrids for chromosome mediated gene transfer (CMGT), we obtained one transformant containing a chromosome fragment derived from the t-complex region located on mouse chromosome 17. It is concluded that the specific chromosome based procedure used here to generate CMGT transfectants may provide a general means to produce large numbers of transfectants containing megabase fragments covering, in principle, all regions of a given chromosome. 相似文献
1000.
General morphology and capsid fine structure of African swine fever virus particles 总被引:11,自引:0,他引:11
JoséL. Carrascosa JoséM. Carazo Angel L. Carrascosa Narciso García Antonio Santisteban Eladio Viñuela 《Virology》1984,132(1):160-172
The structure of African swine fever virus particles has been examined by electron microscopy. The analysis of virions prepared by negative staining, thin sectioning, and freeze-drying and shadowing showed that the virus particle was composed of several concentric structures with an overall icosahedral shape. The inner region of the virus particles was a nucleoid that was surrounded by a membrane covered by the capsid. The capsid had side-to-side dimensions of 172 to 191 nm and was built up by capsomers arranged in an hexagonal lattice. Computer-filtered electron micrographs of either negatively stained or freeze-dried and shadowed capsids revealed capsomers with a hexagonal outline and a hole in the center. The intercapsomer distance ranged from 7.4 to 8.1 nm. The triangulation number of the capsid was estimated to be 189 to 217, indicative of 1892 to 2172 capsomers. Extracellular African swine fever virus particles had an external membrane that resembled the cytoplasmic unit membrane. 相似文献