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71.
Sulfonamide resistance in Neisseria meningitidis isolates of clones of the ET-5 complex 总被引:1,自引:0,他引:1
D A Caugant L O Fr?holm R K Selander K B?vre 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1989,97(5):425-428
A distinctive group of genetically closely related clones, as determined by multilocus enzyme electrophoresis, the ET-5 complex, has been responsible for an epidemic of meningococcal disease in Norway since the mid-1970's. Most isolates of the ET-5 complex from Norway are sulfonamide-resistant, serogroup B, and serotype 15:P1.16. Clones of the ET-5 complex that have been identified as the causative agents of recent outbreaks and epidemics in many other parts of the world show, outside Northern Europe, different associations of serotype protein antigens. We here report the analysis of sulfonamide susceptibility of isolates of the ET-5 complex from various geographic sources. There was no difference in resistance according to geographic source, serogroup, or serotype of the isolates, demonstrating that, in contrast to serotype and serogroup, sulfonamide resistance is an essentially invariant property of clones of the ET-5 complex. 相似文献
72.
Drouin-Garraud V Belgrand M Grünewald S Seta N Dacher JN Hénocq A Matthijs G Cormier-Daire V Frébourg T Saugier-Veber P 《American journal of medical genetics》2001,101(1):46-49
The congenital disorders of glycosylation (CDG) constitute a new group of recessively inherited metabolic disorders that are characterized biochemically by defective glycosylation of proteins. Several types have been identified. CDG-Ia, the most frequent type, is a multisystemic disorder affecting the nervous system and numerous organs including liver, kidney, heart, adipose tissue, bone, and genitalia. A phosphomannomutase (PMM) deficiency has been identified in CDG-Ia patients and numerous mutations in the PMM2 gene have been identified in patients with a PMM deficiency. We report on a French family with 3 affected sibs, with an unusual presentation of CDG-Ia, remarkable for 1) the neurological presentation of the disease, and 2) the dissociation between intermediate PMM activity in fibroblasts and a decreased PMM activity in leukocytes. This report shows that the diagnosis of CDG-Ia must be considered in patients with non-regressive early-onset encephalopathy with cerebellar atrophy, and that intermediate values of PMM activity in fibroblasts do not exclude the diagnosis of CDG-Ia. 相似文献
73.
Berriman M Hall N Sheader K Bringaud F Tiwari B Isobe T Bowman S Corton C Clark L Cross GA Hoek M Zanders T Berberof M Borst P Rudenko G 《Molecular and biochemical parasitology》2002,122(2):131-140
Trypanosoma brucei evades the immune system by switching between Variant Surface Glycoprotein (VSG) genes. The active VSG gene is transcribed in one of approximately 20 telomeric expression sites (ESs). It has been postulated that ES polymorphism plays a role in host adaptation. To gain more insight into ES architecture, we have determined the complete sequence of Bacterial Artificial Chromosomes (BACs) containing DNA from three ESs and their flanking regions. There was variation in the order and number of ES-associated genes (ESAGs). ESAGs 6 and 7, encoding transferrin receptor subunits, are the only ESAGs with functional copies in every ES that has been sequenced until now. A BAC clone containing the VO2 ES sequences comprised approximately half of a 330 kb 'intermediate' chromosome. The extensive similarity between this intermediate chromosome and the left telomere of T. brucei 927 chromosome I, suggests that this previously uncharacterised intermediate size class of chromosomes could have arisen from breakage of megabase chromosomes. Unexpected conservation of sequences, including pseudogenes, indicates that the multiple ESs could have arisen through a relatively recent amplification of a single ES. 相似文献
74.
Raymond S McDermott Frédéric Beuvon Marc Pauly Claude Pallud Anne Vincent-Salomon Veronique Mosseri Pierre Pouillart Susy M Scholl 《Pathobiology》2002,70(6):324-332
AIMS: Cancer cells frequently express antigens capable of being recognized by the host immune system; however, any resultant immune response is often ineffective. This may be related in part to tumor-induced defects in antigen presentation. We screened for dendritic cell infiltration, tumor MHC II expression and associated lymphocytic reaction in the context of three established breast tumor antigens. METHODS: Forty primary breast tumors were evaluated by immunohistochemical techniques for expression of her2/neu, p53, and MUC1 and MHC class II molecules. Twenty-five samples were further analyzed for p53 mutations by PCR-SSCP analysis and DNA sequencing. The phenotype of tumor-infiltrating inflammatory cells was evaluated using the following markers: CD1a, MHC Class II, CD3, CD45, and CD45RO. RESULTS: Tumors with p53 mutations and overexpression, but not her2/neu or MUC1 overexpressing tumors, more frequently harbored marked CD1a+ dendritic cell infiltrates. An overall correlation between CD1a+ cell infiltrates and HLA class II expression on tumor cells (p = 0.0008) was also observed and these tumors had greater CD45RO+ lymphocytic infiltrates. CONCLUSIONS: In breast cancer, p53 mutations may present a more visible signal to the immune system and hence provide a better target for immunotherapy. Infiltrating CD1a positive cells are associated with a more dense tumor lymphocytic infiltrate and tumor cell expression of MHC II molecules. 相似文献
75.
Mitral cell temporal response patterns evoked by odor mixtures in the rat olfactory bulb 总被引:3,自引:0,他引:3
Mammals generally have the ability to extract odor information contained in complex mixtures of molecular components. However, odor mixture processing has been studied electrophysiologically only in insects, crustaceans, and fish. As a first step toward a better understanding of this processing in high vertebrates, we studied the representation of odor mixtures in the rat olfactory bulb, i.e., the second-order level of the olfactory pathways. We compared the single-unit responses of mitral cells, the main cells of the olfactory bulb, to pure odors and to their binary mixtures. Eighty-six mitral cells were recorded in anesthetized freely breathing rats stimulated with five odorants and their 10 binary mixtures. The spontaneous activity and the odor-evoked responses were characterized by their temporal distribution of activity along the respiratory cycle, i.e., by cycle-triggered histograms. Ninety percent of the mixtures were found to evoke a response when at least one of their two components evoked a response. Mixture-evoked patterns were analyzed to describe the modalities of the combination of patterns evoked by the two components. In most of the cases, the mixture pattern was closely similar to one of the component patterns. This dominance of a component over the other one was related to the responsiveness of the cell to the individual components of the mixture, to the molecular nature of the stimulus, and to the coarse shape of individual response patterns. This suggests that the components of binary mixtures may be encoded simultaneously by different odor-specific temporal distributions of activity. 相似文献
76.
77.
Philip Sandblom M.D. Frédéric Saegesser M.D. Velimir Mirkovitch M.D. 《World journal of surgery》1984,8(1):41-50
Hepatic hemobilia is defined as hemorrhage arising from pathological changes in the intrahepatic biliary tract. The main causes are iatrogenic trauma, cholangitis, tumors, and coagulopathy. The salient features of the hemobilia syndrome are described and their causes explained. The treatment, when necessitated by hemorrhage or clot formation, is either resection of the liver or occlusion of the responsible artery by ligature or embolization. The iatrogenic trauma may be operative, resulting from instrumental lesion of the bile ducts, needle biopsy, transhepatic cholangiography, biliary tract prosthesis, or inlaying hepatic artery catheters. Among the inflammatory etiologies, special attention is given to nematodes in the ducts, the tropical hemobilia. Spontaneous hemobilia may, just as nose bleeds or hematuria, result from treatment with anticoagulants.
Résumé L'hémobilie d'origine hépatique répond à l'hémorragie qui provient de lésions situées au niveau des voies biliaires intra-hépatiques. Les causes principales en sont le traumatisme, l'angiocholite, les tumeurs et les troubles de la coagulation. Les caracteres saillants de l'hémobilie sont décrits ainsi que ses causes. Le traitement quand il devient nécessaire en raison de l'importance de l'hémorragie ou de la formation de caillots consiste à réséquer une partie du parenchyme hépatique ou à obtenir l'occlusion de la plaie vasculaire par ligature ou par embolisation.Le traumatisme peut être d'origine iatrogène, qu'il soit le fait d'une lésion instrumentale des canaux biliaires hépatiques, d'une biopsie du foie à l'aiguille, de la cholangiographie transhépatique, ou encore de la présence d'une prothèse au niveau des voies biliaires ou d'un cathéter artériel.Parmi les causes inflammatoires une attention spéciale doit être accordée à l'existence de nématodes au niveau des canaux biliaires intra-hépatiques qui sont à l'origine de l'hémobilie tropicale.L'hémobilie spontanée, comme l'épistaxis ou l'hématurie, peut être la conséquence d'un traitement anti-coagulant.ResumenLa hemobilia hepática se define como hemorragia proveniente de alteraciones patológicas en el tracto biliar intrahepatico. Las causas principales son el trauma iatrogénico, la colangitis, los tumores y la coagulopatía. Se describen las características sobresalientes del síndrome de hemobilia y se explican sus causas. El tratamiento, cuando se hace necesario por hemorragia o por formación de coágulos, es la resección del hígado o la oclusión de la arteria responsable por ligadura o por embolización. El trauma iatrogénico puede ser de origen operatorio, como resultado de lesión instrumental de los canales biliares, biopsia por aguja, colangiografía transhepática, prótesis en el tracto biliar y catéteres colocados en la arteria hepática. Entre las etiologías de naturaleza inflamatoria se presta atención especial a la presencia de nemátodos en los canales, la hemobilia tropical. Al igual de lo que ocurre con las epistaxis o las hematurias, la hemobilia espontanea puede ser consecuencia de tratamientos con anticoagulantes.相似文献
78.
Borgen Nicolai Topstad Olweus Dan Kirkebøen Lars Johannessen Breivik Kyrre Solberg Mona Elin Frønes Ivar Cross Donna Raaum Oddbjørn 《Prevention science》2021,22(8):1147-1158
Prevention Science - The effectiveness of bullying prevention programs has led to expectations that these programs could have effects beyond their primary goals. By reducing the number of victims... 相似文献
79.
Cecilia Nakid-Cordero Sylvain Choquet Nicolas Gauthier Noureddine Balegroune Nadine Tarantino Véronique Morel Nadia Arzouk Sonia Burrel Géraldine Rousseau Frédéric Charlotte Martin Larsen Vincent Vieillard Brigitte Autran Véronique Leblond Amélie Guihot for the K-VIROGREF Study Group 《American journal of transplantation》2021,21(8):2846-2863
EBV-positive and EBV-negative posttransplant lymphoproliferative disorders (PTLDs) arise in different immunovirological contexts and might have distinct pathophysiologies. To examine this hypothesis, we conducted a multicentric prospective study with 56 EBV-positive and 39 EBV-negative PTLD patients of the K-VIROGREF cohort, recruited at PTLD diagnosis and before treatment (2013–2019), and compared them to PTLD-free Transplant Controls (TC, n = 21). We measured absolute lymphocyte counts (n = 108), analyzed NK- and T cell phenotypes (n = 49 and 94), and performed EBV-specific functional assays (n = 16 and 42) by multiparameter flow cytometry and ELISpot-IFNγ assays (n = 50). EBV-negative PTLD patients, NK cells overexpressed Tim-3; the 2-year progression-free survival (PFS) was poorer in patients with a CD4 lymphopenia (CD4+<300 cells/mm3, p < .001). EBV-positive PTLD patients presented a profound NK-cell lymphopenia (median = 60 cells/mm3) and a high proportion of NK cells expressing PD-1 (vs. TC, p = .029) and apoptosis markers (vs. TC, p < .001). EBV-specific T cells of EBV-positive PTLD patients circulated in low proportions, showed immune exhaustion (p = .013 vs. TC) and poorly recognized the N-terminal portion of EBNA-3A viral protein. Altogether, this broad comparison of EBV-positive and EBV-negative PTLDs highlight distinct patterns of immunopathological mechanisms between these two diseases and provide new clues for immunotherapeutic strategies and PTLD prognosis. 相似文献
80.