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11.
Identification of a 35-kilodalton Mycobacterium tuberculosis protein containing B- and T-cell epitopes. 下载免费PDF全文
D Vismara M F Mezzopreti M S Gilardini P Del Porto G Lombardi E Piccolella G Damiani R Rappuoli V Colizzi 《Infection and immunity》1990,58(1):245-251
Screening of a Mycobacterium tuberculosis genomic DNA library in the lambda gt11 expression vector was carried out by using, as probes, sera from tuberculous patients and murine monoclonal antibody H61.3 recognizing a mycobacterial 35-kilodalton protein present only on the M. tuberculosis complex. The recombinant beta-galactosidase-fused protein present in the crude lysate induced the proliferation of T lymphocytes from patients with tuberculous pleuritis. As the recombinant insert contains an internal EcoRI restriction site, it was possible to identify two fragments, one proximal to the lacZ gene and 1.7 kilobases (kb) in size and the other distal to the lacZ gene and 2.2 kb in size. Southern blot analysis showed that both of them hybridized with the genomic DNA from M. tuberculosis and M. bovis but not with the DNA from other mycobacterial species. To perform extensive immunological studies, the amount of beta-galactosidase-fused protein being very low, we fused the 1.7-kb fragment to the N-terminal part of the gene coding for the DNA polymerase of bacteriophage MS2 in the expression vector pEx34. The fusion protein was partially purified, and subsequent Western blotting (immunoblotting) and T-cell proliferation experiments confirmed the presence of B- and T-cell mycobacterial epitopes. Furthermore, to isolate the chromosomal region containing the 35-kilodalton gene, we constructed another mycobacterial genomic library in the lambda 2001 vector by cloning 15 to 20 kb of foreign DNA. Screening of this library was carried out by using 1.7- and 2.2-kb recombinant fragments as probes. Restriction maps of some clones isolated were determined. 相似文献
12.
Although found predominantly in the peritoneal and pleural cavities, B-1 cells are also present in other peripheral tissues such as spleen and lung. While similar in surface phenotypes, such as CD5, all B-1 cells are not equivalent in their response to stimuli. Here, we report that the src family kinase Lck is required to confer the BCR hyporesponsiveness typical of CD5+ B-1 cells and appears involved in the maintenance of their unique function. Splenic B-1 cells express CD5 but not Lck and are not hyporesponsive; however, within the peritoneum, these B-1 cells are induced to express Lck and acquire a hyporesponsive phenotype. Peritoneal B-1 cells from lck-deficient mice, while CD5+, no longer exhibit attenuated BCR signaling. Interestingly, lck-null mice exhibited increased natural antibody levels characteristic of B-1 cells. Taken together, these results demonstrate a key role for Lck in modulating the signaling and cellular fate of B-1 B cells. 相似文献
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Luis Cristovao Porto Michèele Chevallier Jean-Alexis Grimaud 《Virchows Archiv : an international journal of pathology》1989,414(2):129-134
Summary In the present study, hepatic venous distribution per unit of liver surface area on normal wedge biopsies from man (n=11) and baboon (n=8) were analysed and compared. Terminal hepatic veins (THV - man:n=100; baboon:n=200) morphometric size variables were obtained with a Leitz ASM 68K morphometric equipment. THV, defined as hepatic veins up to 150 m in internal diameter (ID), in the centrolobular position and with sinusoidal openings, represented 84% and 74% of hepatic veins of man and baboon, respectively. Four or more THV were generally found on 8 mm2 of liver surface. Transversely sectioned THV selected by the ratio IDminimum/IDmaximum >0.67, was found to be only 25% of the total THV. In baboon, THV merge with other terminal veins and the interlobular veins present sinusoidal inlets. The baboon THV wall surface (WS) and wall thickness (WT) values were higher than in man. Positive correlations between the number of mesenchymal cells (Mc) in the vein wall and wall surface of terminal hepatic veins (man: r= 0.79; baboon: r=0.83) and between wall surface and internal surface (IS) (man: r=0.80; baboon: r=0.72) were found. Two ratios were selected as the most reliable parameters: (1) for the THV wall rim, wall surface/internal surface (WS/IS - man: 0.43±0.16; baboon: 0.63±0.23), regarding transversely sectioned THV; and (2) for the evaluation of wall cell density (WS/Mc-man: 550±231; baboon: 558±183 m2/cell) as they did not depend on THV caliber.Dr. Porto was supported by a fellowship from MEC-CAPES, Brazil. A grant for morphometric equipment was obtained from the Fondation pour la Recherche Médicale and from the Societé d'Hépatologie Expérimentale, 77 rue Pasteur, Lyon, France 相似文献
15.
Luis Cristovao Porto Michèle Chevallier Jean-Alexis Grimaud 《Virchows Archiv : an international journal of pathology》1989,414(4):299-307
Summary Alcohol induced perivenular fibrosis of terminal hepatic veins (THV) is claimed to be a precursor lesion leading to fibrosis development in man and baboon. The nature and significance of the THV lesions found in four baboons chronically fed with alcohol were studied in liver biopsies obtained during a three year period. The surface of THV wall and the number of mesenchymal cells were assessed with a semi-automatic image analyser. Histologically, THV were characterized as (a) phlebitic, in the presence of an inflammatory cell infiltrate involving the venous wall; (b) oedematous, when the connective tissue of the THV wall was disrupted or dissociated and (c) fibrotic, when perivenular scarring appeared as an increased rim. These lesions were present simultaneously and their intensity and distribution were independent of the duration of alcohol intoxication. Morphometric data obtained from these THV confirmed the thickening of the THV wall (WS/IS in: oedematous 1.05±0.36; phlebitic 1.65±1.04; fibrotic 1.47±0.36); and revealed an increased number of mesenchymal cells in fibrotic (439 m2/cell;p<0.01) and in phlebitic THV (510 m2/cell;p<0.05). A constant relationship was found between phlebitis and the presence of inflammatory infiltrate within the hepatic acini. Fibrotic THV was a less frequent finding and the lesion disappeared in the sequential biopsies of one of the baboons. In conclusion, THV lesions were heterogeneous and the collagen deposition in the THV wall was potentially reversible during the three year alcohol intoxication period, regardless the inflammatory reaction and, thus, did not indicate early irreversible hapatic fibrosis.Dr. Porto was supported by a fellowship from MEC-CAPES, Brazil. A grant for morphometric equipment was obtained from the Fondation pour la Recherche Médicale and from the Societé d'Hépatologie Expérimentale, 77 rue Pasteur, Lyon, France 相似文献
16.
Porto CM Lazzarini MP Redígolo LR Neves FR 《Revista latino-americana de enfermagem》1999,7(5):121-126
This paper emphasizes the creation and application of a KIT for the communication of occupational accidents with puncture-cutting objects to the Municipal Health Bureau from the city of Ribeir?o Preto. It is an essential instrument for the health care services directed to all the employees of the Health Units. It also evidences the notification and the beginning of the prevention of occupational diseases, being a highly useful instrument whenever any accident occurs. The creation of this KIT enabled the use of prevention measures regarding occupational diseases, culminating with the mobilization of the chiefs and the staff in order to intensify preventive procedures. 相似文献
17.
Menéndez López V Molina Porto R Alcaraz Asensio A Gutiérrez del Pozo R Alcover García JA 《Actas urologicas espa?olas》2000,24(7):530-535
Contribution of 60 patients with primary surface transitional cell tumours of the bladder where nuclear expression of p53 protein was prospectively studied and compared to known prognostic factors in an attempt to find out its role in the development of relapses. An statistically significant relationship was found between the protein expression and cytology, tumoral multifocality, stage, relapse development and tumoral progression. It can be concluded that expression of this protein can be of use as relapse predictor. 相似文献
18.
Neuroendocrine carcinoma of the larynx 总被引:1,自引:0,他引:1
Neoplasms of the larynx showing neuroendocrine differentiation are uncommon, with less than 100 previously reported cases. These tumors encompass subcategories that have been designated heretofore as "malignant carcinoid" and "oat cell carcinoma" and have been associated with ectopic production of neuropeptides and biogenic amines. We report a case of neuroendocrine carcinoma that arose in the epiglottis in an elderly man, metastasized widely, and was responsible for death. Immunohistochemical studies showed the presence of serotonin, calcitonin, ACTH, met-enkephalin, chromogranin, and neuron-specific enolase within tumor cells, although clinical endocrinopathy was absent. This case is used as a focus for discussion of the spectrum of neuroendocrine tumors of the head and neck, including recommended treatment approaches for such neoplasms. 相似文献
19.
Martins Thales Valle José R. Porto A. 《Pflügers Archiv : European journal of physiology》1939,242(2):155-167
Zusammenfassung Die Kontraktilität und Reaktivität auf Drogen invitro von Samenleiter und Samenblase normaler, kastrierter und kastrierter, vorhergehend mit Testosteron-Propionat oder Oestradiol-Benzoat behandelter Rhesus-Affen, wurde untersucht.Spontane, automatische Kontraktionen wurden nur bei Organen, die von Kastraten oder mit Oestradiol-Benzoat behandelten Kastraten herrührten, beobachtet.Auch die Reaktivität auf die verschiedenen untersuchten Drogen zeigt sehr deutliche Variationen.Adrenalin, Acetylcholin und Nicotin wirken auf alle untersuchten Organe erregend. Jedoch Bariumchlorid, Ephedrin, Histamin, Hydrastinin und Yohimbin rufen, in den untersuchten Dosen, nur bei Organen von kastrierten oder mit Oestradiol-Benzoat behandelten Tieren Kontraktionen hervor.Wir schließen daraus, daß, wie wir schon an der Ratte und der Katze zeigten, die Sexualhormone eine bedeutende Rolle bei der Regulierung der Motilität der akzessorischen Genitalien des Rhesus-Affen spielen; Testosteron hemmt und Oestradiol stimuliert.Die Kontraktilität und die erwähnten Unterschiede im Verhalten zeigen sich noch nach Aufbewahren der Organe während mehrerer Tage bei 3 bis 6°C, wenn man den Versuch bei 36–38°C wiederholt. Eine Reaktion auf Adrenalin konnte bei Samenleitern, die bis zu 40 Tagen, und bei Samenblasen, die bis zu 8 Tagen unter jenen Bedingungen aufbewahrt wurden, festgestellt werden.Einige vorläufige Versuche mit Nebenhoden und Prostata von Rhesus-Affen scheinen zu zeigen, daß diese Organe auch einer hormonalen Kontrolle, ebenso wie die Samenleiter und Samenblasen, unterliegen.Die Übertragung dieser Daten für die Erklärung einiger Fragen der normalen und pathologischen Sexualphysiologie und Pharmakologie wird angezeigt. 相似文献
20.