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991.
Immune evasion by Lyme spirochetes is a multifactorial process involving numerous mechanisms. The OspE protein family undergoes antigenic variation during infection and binds factor H (fH) and possibly FHL-1/reconectin. In Borrelia burgdorferi B31MI, the OspE family consists of three paralogs: BBL39 (ErpA), BBP38, and BBN38 (ErpP). BBL39 and BBP38 are identical and therefore are referred to here as BBL39. The goals of this study were to assess the specificity of the antibody (Ab) response to the OspE paralogs and to identify the domains or determinants of OspE that are required for the binding of fH and OspE-targeting Abs that develop during infection. Here we demonstrate that at least some of the anti-OspE Abs produced during infection are paralog specific and that Ab binding requires conformational determinants whose formation requires both the N- and C-terminal domains of OspE. The binding of fH to OspE was also found to be dependent on conformational determinants. It is also demonstrated here that all of the OspE paralogs expressed by B. burgdorferi B31MI are capable of binding fH. The binding of fH to members of the OspF protein family was also assessed. In contrast to an earlier report, no binding of BBO39 or BBR42 to human fH was detected. Lastly, a series of competitive binding enzyme-linked immunosorbent assay analyses, designed to determine if fH and infection serum Abs bind to the same sites on OspE, revealed that these ligands interact with different regions of OspE. 相似文献
992.
WIF1, a component of the Wnt pathway, is down-regulated in prostate, breast, lung, and bladder cancer 总被引:19,自引:0,他引:19
993.
994.
We present the first case of Holt-Oram syndrome associated with the lethal congenital heart defect of hypoplastic left heart syndrome. The possible pathophysiological link is explored and the need for careful genetic and cardiologic evaluation in these patients is reiterated. 相似文献
995.
Prevention of Postinfectious Asthma in Children by Reducing Self-Inoculatory Behavior 总被引:1,自引:0,他引:1
Cortey Donald L.; Gevirtz Richard; Nideffer Robert; Cummins Leo 《Journal of pediatric psychology》1987,12(4):519-531
Recent studies have shown that the spread of infectious nasalsecretions from hand-to-hand or hand-to-object, followed byself-inoculation is an efficient means of viral transmission.The present study was designed to investigate whether self-inoculationbehavior in asthmatic children could be reduced and, if so,whether this reduction would reduce the frequency of infectionand asthma. Sixteen subjects aged 4 to 8, all diagnosed withpostinfectious asthma, were assigned to a treatment (differentialreinforcement of other behavior and contingent education) orplacebo control condition. Results indicate that self-inoculatorybehavior, infection, and asthma were signjficantly reduced.These findings may indicate an important role for behavioralmedicine inpostinfectious asthma. 相似文献
996.
Stereospecific monoclonal antibodies to nicotine and cotinine and their use in enzyme-linked immunosorbent assays 总被引:2,自引:0,他引:2
Robert J. Bjercke Gary Cook Norman Rychlik Hilda B. Gjika Helen Van Vunakis John J. Langone 《Journal of immunological methods》1986,90(2):203-213
Stereospecific monoclonal antibodies (McAb) have been prepared against the tobacco alkaloid (S)-(-)-nicotine and its major metabolite (S)-(-)-cotinine. Nine anti-nicotine and 4 anti-cotinine hybridomas, selected by a screening procedure that utilized immunoprecipitation of the 3H-labeled natural isomers of nicotine or cotinine, were grown in the ascites fluid of pristane-primed syngeneic BALB/c mice. Antibodies in concentrations up to 7.5 mg/ml ascites and with binding affinities that generally exceeded 108 M−1 were obtained. Enzyme-linked immunosorbent assays (ELISAs) were developed in which nicotine or cotinine derivatives bound covalently to poly-
-lysine werecoated onto wells of polyvinyl chloride microtiter plates. Coated wells were incubated sequentially with McAb in the presence or absence of inhibitor, rabbit anti-mouse immunoglobulin, then horseradish peroxidase-labeled protein A (HRP-SpA) before addition of substrate. The antibodies are highly specific and show minimal cross-reactivity with several nicotine metabolites and other structurally related compounds. In the respective assays, only 0.25 ng (S)-(-)-nicotine and 0.12 ng (S)-(-)-cotinine are required to give 50% inhibition of antibody binding, and as little as 0.05 ng nicotine and 0.02 ng cotinine give 15% inhibition. These assays are 5–10 times more sensitive than analogous ELISAs developed with rabbit antisera and HRP-SpA or conventional radioimmunoassays (RIAs) that utilize the rabbit antisera and 3H-labeled ligands. There was good correlation between the levels of nicotine (r = 0.967) found in saliva samples from smokers and non-smokers assayed by McAb-based ELISAs and conventional RIAs. 相似文献
997.
998.
Gregory A Hale Laura C Bowman Richard J Rochester Eli Benaim Helen E Heslop Robert A Krance Edwin M Horwitz John M Cunningham Xin Tong Deo Kumar Srivastava Rupert Handgretinger Deborah P Jones 《Biology of blood and marrow transplantation》2005,11(11):912-920
Hemolytic uremic syndrome (HUS) is an uncommon but potentially life-threatening complication of hematopoietic stem cell transplantation. We retrospectively studied the medical records of 293 children who underwent allogeneic bone marrow transplantation at St. Jude Children's Research Hospital between 1992 and 1999 to describe the clinical course of and to identify risk factors for transplant-associated HUS. Conditioning regimens included cyclophosphamide, cytarabine, and total body irradiation for patients with hematologic malignancies (n = 244); patients with nonmalignant diseases (n = 49) received disease-specific regimens. Grafts from unrelated or mismatched related donors were depleted of T lymphocytes, whereas matched sibling grafts were unmanipulated. All patients received cyclosporine as prophylaxis for graft-versus-host disease. Recipients of grafts from matched siblings also received pentoxifylline or short-course methotrexate. HUS developed in 28 (9.6%) patients at a median of 171 days after transplantation. We identified older donor age (P = .029), use of antithymocyte globulin in the conditioning regimen (P = .008), and recipient CMV seronegativity (P = .011) as being associated with an increased risk of HUS. With a multiple regression analysis, the use of antithymocyte globulin (beta = .86; P = .04) and recipient cytomegalovirus seronegativity (beta = .93; P = .035) remained significant risk factors for the development of HUS. 相似文献
999.
Kenefick RW Mahood NV Hazzard MP Quinn TJ Castellani JW 《European journal of applied physiology》2004,92(4-5):565-570
Hyperosmotic hypovolemia impairs vasoconstriction during sedentary cold exposure. The purpose of this study was to determine whether hypohydration alters thermoregulation and cardiovascular responses to exercise in cold air. On four occasions, eight males [35.1 (2.7) years, 175.5 (3.1) cm, 73.3 (2.6) kg, 57.2 (2.6) ml kg–1 min–1 maximal oxygen uptake (O2max), 19.6 (2.4)% fat] walked, in t-shirt, shorts, and shoes, at 50% O2max, for 60 min in either a 4°C (Cold) or a 25°C (Temperate) environment in both hypohydrated state (HYPO, –4% body mass) and euhydrated state (EU). During exercise–cold stress, rectal temperature (Tre), mean weighted skin temperature, heart rate (HR), cardiac output (CO), and stroke volume (SV) were measured every 20 min. Mean weighted skin temperature values were not different between HYPO and EU but were lower (P<0.05) in Cold versus Temperate trials. Tre was not different (P>0.05) between HYPO–Cold and EU–Cold. CO and SV were not different within hydration states and were not different between Cold and Temperate trials (P<0.05). HR was not different between HYPO–Cold and EU–Cold. These data demonstrate that moderate intensity exercise in the cold while hypohydrated does not alter metabolic heat production, skin temperatures and heat loss, nor does it increase thermoregulatory and cardiovascular strain. 相似文献
1000.
Haupt SS Spengler F Husemann R Dinse HR 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2004,155(4):485-499
We recorded neurons extracellularly in layers II/III, IV, and V of the hindpaw representation of primary somatosensory cortex in anesthetized rats and studied laminar features of receptive fields (RFs) and representational maps. On average, RFs were smallest in layer IV and largest in layer V; however, for individual penetrations we found substantial deviations from this rule. Within the hindpaw representation, a distinct rostrocaudal gradient of RF size was present in all layers. While layer V RFs were generally largest independent of this gradient, layer IV RFs recorded caudally representing the proximal portions of the paw were larger than layer II/III RFs recorded rostrally representing the digits. The individual scatter of the locations of RFs across laminar groups was in the range of several millimeters, corresponding to about 25% of the average RF diameter. The cutaneous representations of the hindpaw in extragranular layers were confined to the areal extent defined by responsive sites in layer IV. Comparison between RFs determined quantitatively and by handplotting showed a reliable correspondence. Repeated measurements of RFs revealed spontaneous fluctuations of RF size of no more than 5% of the initial condition over an observation period of several hours. The topography and variability of cortical maps of the hindpaw representation were studied with a quantitative interpolation method taking into account the geometric centers of RFs and the corresponding cortical recording sites. On average, the overall topography in terms of preservation of neighborhood relations was present in all layers, although some individual maps showed severe distortions of topography. Factors contributing to map variability were overall position of the representation on the cortical surface, internal topography and spatial extent. Interindividual variability of map layout was always highest in the digit representations. Local topographic orderliness was lowest in layer V, but comparable in layers II/III and IV. Within layer IV, the lowest orderliness was observed in the digit representations. Our data emphasize a substantial variability of RF size, overlap and position across layers and within layers. At the level of representational maps, we found a similar degree of variability that often co-varied across layers, with little evidence for significant layer specificity. Laminar differences are likely to arise from the specific input-output pattern, layer-specific cell types and the connectivity between different layers. Our findings emphasizing similarities in the variability across layers support the notion of tightly coupled columnar interactions between different layers. 相似文献