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21.
22.
Nabarra B Martinon C Godard C Vasseur F de Ribains G Miquerol L Kahn A Ezine S 《Developmental immunology》2002,9(4):223-231
Bone marrow progenitors migrate to the thymus, where they proliferate and differentiate into immunologically competent T cells. In this report we show that mice transgenic for SV40 T and t antigens under the control of the L-pyruvate kinase promoter develop, in a first step, thymic hyperplasia of both thymocytes and epithelial cells. Morphological studies (histology, immunohistolabeling and electron microscopy) revealed modifications of the thymic microenvironment and gradual expansion of medullary epithelial cells in 1 month-old mice, taking over the cortical region. Then, a thymic carcinoma develops. Two-color labeling of frozen sections identified the transgene in medullary epithelial cells. Flow cytometry analysis demonstrated a marked increase in mature CD4+ and CD8+ thymocytes in adult mice (39 +/- 10 x 10(6) in transgenic mice and 12 +/- 5 x 10(6) in age-matched controls). Furthermore, thymocyte export was disturbed. 相似文献
23.
Lawrence G. Lum Edith Burns Marleen M. Janson Paul J. Martin Bernadette R. Giddings Margaret C. Seigneuret Jan E. Noges Sandra C. Galoforo 《Journal of clinical immunology》1990,10(5):255-264
This investigation uses a system for inducing and detecting anti-tetanus toxoid antibody (anti-TT) synthesis to study specific antibody (Ab) synthesis by bone marrow mononuclear cells (MC). We measured the amounts of anti-TT secreted and the number of B cells secreting antibody (Ab). The ELISA plaque detects single B cells secreting specific Ab. The results show that (1) spontaneous anti-TT secretion by MC is higher than spontaneous anti-TT secretion by peripheral blood lymphocytes (PBL) using an ELISA plaque (P<0.01); (2) spontaneous anti-TT production by MC correlated with the serum anti-TT titers as measured by an ELISA (r=0.75,P=0.005); (3) two types of marrow B cells were identified—one that spontaneously secretes anti-TT and another that produces anti-TT after TT-stimulation; (4) the frequency of anti-TT-secreting B cells is higher in MC than in PBL; (5) the amount of Ab secreted per marrow B cell is not different from that secreted by a peripheral B cell; and (6) marrow B cells could be induced to produce anti-TTin vitro up to 10 months without added cytokines. These results show that bone marrow is a major repository for differentiated B cells that spontaneously produce Abs to maintain circulating Abs titers and for memory B cells that can be induced to produce specific Ab. 相似文献
24.
B Lebeau R Grillot M Michallet A Goullier-Fleuret B Corront J P Bru 《Annales de biologie clinique》1987,45(5):582-587
This study took place between February 1984 and February 1985 in 76 febrile neutropenic patients. We evaluated the whole mycological and serological results, in 91 febrile episodes. We separated two groups: group I (acute leukemia, chronic myelo?d leukemia, medullar aplasia, lymphomas) and group II (chronic lympho?d leukemia, Hodgkin disease, myelomas, solid tumors). Patients were included in this study if they developed a temperature of 38.5 degrees C or greater and if they had less than five hundred neutrophils per mm3. They were treated with mono or bi-antibiotherapy. If the patient remained febrile more than 72 hours, an antifungal therapy was added (Amphotericin B IV). Through these weekly results, we conclude: the high frequency of digestive tract candidiasis in such patients; disseminated candidiasis occurs only in the first group patients with fungal digestive colonization; the overall response rate in this study was 77 per cent. This underlines the interest of empiric treatment with amphotericin B IV. 相似文献
25.
Clinical Features of Fatal Familial Insomnia: Phenotypic Variability in Relation to a Polymorphism at Codon 129 of the Prion Protein Gene 总被引:2,自引:0,他引:2
Pasquale Montagna Pietro Cortelli Patrizia Avoni Paolo Tinuper Giuseppe Plazzi Roberto Gallassi Francesco Portaluppi Jean Julien Claude Vital Marie Bernadette Delisle Pierluigi Gambetti Elio Lugaresi . 《Brain pathology (Zurich, Switzerland)》1998,8(3):515-520
Fatal Familial Insomnia is a hereditary prion disease characterized by a mutation at codon 178 of the prion protein gene cosegregating with the methionine polymorphism at codon 129 of the mutated allele. It is characterized by disturbances of the wake-sleep cycle, dysautonomia and somatomotor manifestations (myoclonus, ataxia, dysarthria, spasticity). PET studies disclose severe thalamic and additionally cortical hypometabolism. Neuropathology shows marked neuronal loss and gliosis in the thalamus, especially the medio-dorsal and anterior-ventral nuclei, olivary hypertrophy and some spongiosis of the cerebral cortex. Detailed analysis of 14 cases from 5 unrelated families showed that patients ran either a short (9.1+ 1.1 months) or a prolonged (30.8 + 21.3 months) clinical course according to whether they were homozygote met/met or heterozygote met/val at codon 129. Moreover, homozygotes had more prominent oneiric episodes, insomnia and dysautonomia at onset, whereas heterozygotes showed ataxia and dysarthria at onset, earlier sphincter loss and epileptic Grand Mai seizures; they also displayed more extensive cortical involvement on PET and at postmortem examination. Our data suggest that the phenotype expression of Fatal Familial Insomnia is related, at least partly, to the polymorphism at codon 129 of the prion protein-gene. 相似文献
26.
Algros MP Collonge-Rame MA Bedgejian I Tropet Y Delattre O Kantelip B 《Annales de pathologie》2003,23(3):244-248
Extraskeletal myxoid chondrosarcoma (EMC) is a phenotypically and genotypically distinct entity with a protracted course. A documented case of an extraskeletal myxoid chondrosarcoma characterized by a t(9; 17) (q22; q11) translocation with a neuroendocrine and neural differentiation is reported. 相似文献
27.
Analysis of the genomic sequence of a human metapneumovirus 总被引:44,自引:0,他引:44
We recently described the isolation of a novel paramyxovirus from children with respiratory tract disease in The Netherlands. Based on biological properties and limited sequence information the virus was provisionally classified as the first nonavian member of the Metapneumovirus genus and named human metapneumovirus (hMPV). This report describes the analysis of the sequences of all hMPV open reading frames (ORFs) and intergenic sequences as well as partial sequences of the genomic termini. The overall percentage of amino acid sequence identity between APV and hMPV N, P, M, F, M2-1, M2-2, and L ORFs was 56 to 88%. Some nucleotide sequence identity was also found between the noncoding regions of the APV and hMPV genomes. Although no discernible amino acid sequence identity was found between two of the ORFs of hMPV and ORFs of other paramyxoviruses, the amino acid content, hydrophilicity profiles, and location of these ORFs in the viral genome suggest that they represent SH and G proteins. The high percentage of sequence identity between APV and hMPV, their similar genomic organization (3'-N-P-M-F-M2-SH-G-L-5'), and phylogenetic analyses provide evidence for the proposed classification of hMPV as the first mammalian metapneumovirus. 相似文献
28.
Sylvie Degermann Christina Reilly Bernadette Scott Lynn Ogata Harald Von Boehmer David Lo 《European journal of immunology》1994,24(12):3155-3160
Autoimmune (type 1) diabetes mellitus in mouse, rat, and humans shares several features, including T lymphocyte infiltration into pancreatic islets and a dependence on permissive class II major histocompatibility complex (MHC) alleles. We report here on an experimental model involving mice that express influenza hemagglutinin (HA) under the control of the insulin promoter and, at the same time, a transgenic class II MHC-restricted T cell receptor (TcR) specific for an HA peptide. These mice spontaneously develop islet infiltrates resembling those found in NOD mice and most animals become diabetic within 8 weeks of age. Because of the availability of a clonotypic TcR antibody, we can be confident that the Ins-HA transgene does not induce any measurable alterations in the vast majority of T cells with the transgenic TcR in primary and secondary lymphoid organs. Continuous export of large numbers of HA-specific lymphocytes from the thymus was not required for the manifestation of the disease since mice thymectomized at 3 days after birth still developed the disease albeit with smaller infiltrates. 相似文献
29.
Beasley MB Franks TJ Galvin JR Gochuico B Travis WD 《Archives of pathology & laboratory medicine》2002,126(9):1064-1070
CONTEXT: The histologic patterns of diffuse alveolar damage (DAD), bronchiolitis obliterans with organizing pneumonia (BOOP), and eosinophilic pneumonia (EP) are well-recognized histologic patterns of lung injury associated with an acute or subacute clinical presentation. We have recognized acute fibrinous and organizing pneumonia (AFOP) as a histologic pattern, which also occurs in this clinical setting but does not meet the classic histologic criteria for DAD, BOOP, or EP and may represent an underreported variant. OBJECTIVE: To investigate the clinical significance of the AFOP histologic pattern and to explore its possible relationship to other disorders, including DAD and BOOP. DESIGN: Open lung biopsy specimens and autopsy specimens were selected from the consultation files of the Armed Forces Institute of Pathology, which showed a dominant histologic pattern of intra-alveolar fibrin and organizing pneumonia. Varying amounts of organizing pneumonia, type 2 pneumocyte hyperplasia, edema, acute and chronic inflammation, and interstitial widening were seen. Cases with histologic patterns of classic DAD, BOOP, abscess formation, or eosinophilic pneumonia were excluded. To determine the clinical behavior of patients with this histologic finding, clinical and radiographic information and follow-up information were obtained. Statistical analysis was performed using Kaplan-Meier and chi(2) analysis. RESULTS: Seventeen patients (10 men, 7 women) with a mean age of 62 years (range, 33-78 years) had acute-onset symptoms of dyspnea (11), fever (6), cough (3), and hemoptysis (2). Associations believed to be clinically related to the lung disease included definitive or probable collagen vascular disease (3), amiodarone (1), sputum culture positive for Haemophilus influenza (1), lung culture positive for Acinetobacter sp. (1), lymphoma (1), hairspray (1), construction work (1), coal mining (1), and zoological work (1). Six patients had no identifiable origin or association. Follow-up revealed 2 clinical patterns of disease progression: a fulminate illness with rapid progression to death (n = 9; mean survival, 0.1 year) and a more subacute illness, with recovery (n = 8). Histologic analysis and initial symptoms did not correlate with eventual outcome, but 5 of the 5 patients who required mechanical ventilation died (P =.007). CONCLUSIONS: Acute fibrinous and organizing pneumonia is a histologic pattern associated with a clinical picture of acute lung injury that differs from the classic histologic patterns of DAD, BOOP, or EP. Similar to these patterns of acute lung injury, the AFOP pattern can occur in an idiopathic setting or with a spectrum of clinical associations. The overall mortality rate is similar to DAD and therefore may represent a histologic variant; however, AFOP appears to have 2 distinct patterns of disease progression and outcome. The need for mechanical ventilation was the only parameter that correlated with prognosis. None of the patients with a subacute clinical course required mechanical ventilation. 相似文献
30.
Savage ND Harris SH Rossi AG De Silva B Howie SE Layton GT Lamb JR 《European journal of immunology》2002,32(10):2905-2914
The generation of a productive primary immune response is dependent on the ability of na?ve T lymphocytes to recirculate through peripheral lymph organs to encounter specific antigen. The process of na?ve CD4(+) T cell entry into lymph nodes correlates with cell surface expression of L-selectin (CD62L), which mediates early tethering and rolling events to endothelium prior to entry. Here, we demonstrate that surface expression of CD62L enhances CD4(+) T cell activation in vitro. The synthetic hydroxamate metalloproteinase inhibitor (BB-3103), specifically inhibits activation-induced shedding of CD62L from CD4(+) T cells by TCR cross-linking and lowers proliferation in part by reducing rapid tyrosine phosphorylation of zeta-associated protein 70 kDa (ZAP-70) and by increasing cytosolic free Ca(2+) concentration mobilization. BB-3103 also inhibited the proliferative response of both murine CD4(+) Th1 and Th2 subsets in vitro but the inhibitory effects were sustained only in Th2-type cells. Similarly, BB-3103 mediated prolonged inhibition of allergen-dependent peripheral T cell proliferation in atopic dermatitis patients but not in healthy controls. Analysis of CD62L expression on murine CD4(+) T cell subsets revealed that surface expression was maintained on Th1 cells but not Th2 cells. The differential effects of BB-3103 on primed effector CD4(+) T cells may provide new insights into generating therapeutic agents capable of redressing the Th2/Th1 imbalance in allergic diseases. 相似文献