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61.
Group a streptococcal antigens cross-reactive with myocardium. Purification of heart-reactive antibody and isolation and characterization of the streptococcal antigen 总被引:25,自引:17,他引:25 下载免费PDF全文
Heart-reactive antibody (HRA) appears in the sera of experimental animals inoculated with group A streptococci as well as patients with acute rheumatic fever. Adsorption of either serum with group A streptococcal membranes will remove the HRA. Blocking experiments between these two types of HRAs have demonstrated that the antibodies are directed towards different antigenic determinants on either the same or different molecules. To isolate and purify the antigen from the group A streptococcus cross-reactive with sarcolemmal sheaths of cardiac myofibers, it became necessary to purify the HRA from rheumatic fever patients’ sera. Isolated gamma globulin containing all of the HRA was adsorbed onto human sarcolemmal sheaths. The specific HRA was released by using potassium iodide. Over 99 percent of the purified HRA was shown to bind the sarcolemmal sheath whereas less than 1 percent of the antibody would bind nonspecifically to other material. Preparations of group A streptococcal membrane will bind HRA purified from the sera of acute rheumatic patients at levels of 97 percent or greater. The cross-reactive antigen solubilized by nonionic detergent was purified 120-fold by column chromatography. On sodium dodecyl sulfate polyacrylamide electrophoresis, the antigen was demonstrated to be composed of four polypeptides with mol wt of 32,000, 28,000, 26,000, and 22,000 daltons, respectively. Only proteolytic enzymes could destroy the antigenic determinant whereas glycosidases and lipases had no effect. The purified antigen blocked the binding of purified HRA to normal human heart sections. 相似文献
62.
JB Robins MRCOG 《International journal of clinical practice》1995,49(3):164-165
SUMMARY A case of cord presentation associated with the presence of a complex true knot is described and the aetiology and risks reconsidered. 相似文献
63.
Prevalence of cytomegalovirus antibody in hemophiliacs and homosexuals infected with human immunodeficiency virus type 1 总被引:1,自引:0,他引:1
We determined the prevalence of antibody to cytomegalovirus (CMV) in the sera of non-homosexual hemophilia patients and homosexual men infected with the human immunodeficiency virus type 1 (HIV-1). CMV antibody testing by latex agglutination revealed 33 of 58 HIV-1 infected hemophiliacs (57%) were antibody-positive compared with 54 of 54 HIV-1 infected asymptomatic non-hemophiliac homosexuals (100%) (p less than .001). Nine of 15 hemophiliacs (60%) with symptomatic HIV-1 infection were CMV antibody-positive. We also tested 22 HIV-1 antibody-negative hemophiliacs who had received non-heat treated factor concentrates. 14 of these 22 (64%) were CMV antibody-positive compared with 57% of HIV-1 antibody-positive hemophiliacs. We conclude 1) there is little correlation between transmission of HIV-1 and CMV by factor concentrates, 2) the presence of CMV antibody does not appear to be associated with clinical stage of HIV-1 infection in hemophiliacs, and 3) there may be a significant number of CMV antibody-negative hemophiliacs with HIV-1 infection at risk for primary infection and subsequent disease if CMV seronegative blood products are not provided for future transfusions. 相似文献
64.
Steffen E Petersen Joseph B Selvanayagam Jane M Francis Saul G Myerson Frank Wiesmann Matthew D Robson Ingegerd Ostman-Smith Barbara Casadei Hugh Watkins Stefan Neubauer 《Journal of cardiovascular magnetic resonance》2005,7(3):551-558
PURPOSE: Determination of the underlying etiology of left ventricular hypertrophy (LVH) is a common, challenging, and critical clinical problem. The authors aimed to test whether pathological LVH, such as occurs in hypertrophic cardiomyopathy (HCM), hypertensive heart disease, or aortic stenosis, and physiological LVH in athletes, can be distinguished by means of left ventricular volume and geometric indices, derived from cardiovascular magnetic resonance imaging. METHODS: A total of 120 subjects were studied on a 1.5 Tesla MR (Sonata, Siemens Medical Solutions, Erlangen, Germany) scanner, comprising healthy volunteers (18), competitive athletes (25), patients with HCM (35), aortic stenosis (24), and hypertensive heart disease (18). Left ventricular mass index, ejection fraction, end-diastolic, end-systolic and stroke volume index, diastolic wall thickness, wall thickness ratio and diastolic and systolic wall-to-volume ratios were determined. RESULTS: Left ventricular (LV) mass indices were similar for all forms of LVH (p > 0.05), which were at least 35% higher than those obtained in healthy volunteers (p < 0.05). Multiple logistic regression showed that the percentage of correctly predicted diagnoses was 100% for athlete's heart, 80% for hypertrophic cardiomyopathy, 54% for aortic stenosis, and 22% for hypertensive heart disease. Using a receiver operating curve-determined cut-off value for diastolic wall-to-volume ratio of less than 0.15 mm x m2 x ml(-1), athletes' hearts could be differentiated from all forms of pathological cardiac hypertrophy with 99% specificity. CONCLUSIONS: Athlete's heart can be reliably distinguished from all forms of pathological cardiac hypertrophy using CMR-derived LV volume and geometric indices, but pathological forms of LVH present with overlapping cardiac hypertrophy phenotypes. This capability of CMR should be of high clinical value. 相似文献
65.
Hans HCM Savelberg Nicolaas C Schaper Paul JB Willems Ton LH de Lange Kenneth Meijer 《BMC musculoskeletal disorders》2009,10(1):16
Background
Patients with diabetic polyneuropathy (DPN) are often confronted with ulceration of foot soles. Increased plantar pressure under the forefoot has been identified as a major risk factor for ulceration. This study sets out to test the hypothesis that changes in gait characteristics induced by DPN related muscle weakness are the origin of the elevated plantar pressures. 相似文献66.
Osama Al‐Jabrah BDS MSc JBPD Raghda Al‐Shammout BDS JBOrth Waddah El‐Naji BDS JBRestDent Mahasen Al‐Ajarmeh BDS JBPD Abdel‐Hakeem Al‐Quran BDS JB 《Journal of prosthodontics》2010,19(4):286-293
Purpose: The aims of this study were to compare gender differences in the width and length of the maxillary right central incisor and the horizontal and vertical overlap of the anterior teeth and to determine the relationships of these two intraoral dental biometric measurements with the amount of gingival display during smiling. Materials and Methods: A total of 61 men and 66 women were included in this study. For each participant, the gingival tissue display during smiling was judged to be either visible or not, and the maximum mesiodistal and incisogingival dimensions of the maxillary right central incisor were measured, along with the amount of horizontal and vertical overlap of anterior teeth using a digital caliper. Gender differences in these parameters and the relationship between subjects showing gingival display when smiling and the two intraoral dental biometric measurements were determined. Statistical analyses of data were performed using SPSS (V11) software. The mean scores for gender were calculated, and a Student's t‐test was used to identify significant differences between both groups. Significance level was set to 0.05. Results: The age of the participants ranged between 23 and 52, with a mean of 33.47 ± 9.07 years. A relatively small percentage of the subjects (22.05%) displayed gingiva when smiling. More women displayed gingiva when smiling than men, with a 2:1 female:male ratio. Men exhibited significantly (p < 0.05) wider (8.76 ± 0.66 mm) and longer (10.28 ± 0.88 mm) central incisors compared to women (7.92 ± 0.72 mm; 9.27 ± 0.93 mm width and length, respectively). No gender differences were found in the width‐to‐length ratio. Subjects with gingival display had significantly more horizontal (4.28 ± 1.21 mm; p < 0.001), and vertical (3.52 ± 0.66 mm; p < 0.05) overlap of anterior teeth compared to those who did not display gingiva when smiling (2.40 ± 1.03 and 2.30 ± 0.93 mm, respectively). Conclusions: Significantly more women displayed gingiva in smiling. Men had significantly wider and longer central incisors. No differences were recorded between men and women relative to both the horizontal and vertical anterior tooth overlap. Subjects who displayed gingiva when smiling had more horizontal and vertical overlap of anterior teeth. 相似文献
67.
CE Vitor CP Figueiredo DB Hara AF Bento TL Mazzuco JB Calixto 《British journal of pharmacology》2009,157(6):1034-1044
Background and purpose:
α- and β-amyrin are pentacyclic triterpenes found in plants and are known to exhibit pronounced anti-inflammatory effects. Here, we evaluated the effects of a 1:1 mixture of α- and β-amyrin (α,β-amyrin) on an experimental model of colitis in mice.Experimental approach:
Colitis was induced in Swiss male mice by trinitrobenzene sulphonic acid (TNBS) and followed up to 72 h; animals were treated systemically with α,β-amyrin, dexamethasone or vehicle. Macro- and microscopic damage, myeloperoxidase activity and cytokine levels were assessed in colons. Histological sections were immunostained for cyclooxygenase-2 (COX-2), vascular endothelial growth factor, phospho-p65 nuclear factor-κB (NF-κB) and phospho-cyclic AMP response element-binding protein (CREB)Key results:
TNBS-induced colitis was associated with tissue damage, neutrophil infiltration and time-dependent increase of inflammatory mediators. Treatment with α,β-amyrin (3 mg·kg−1, i.p.) or dexamethasone (1 mg·kg−1, s.c.) consistently improved tissue damage scores and abolished polymorphonuclear cell infiltration. α,β-Amyrin, like dexamethasone, significantly diminished interleukin (IL)-1β levels and partially restored IL-10 levels in colon tissues 72 h after colitis induction, but only α,β-amyrin reduced vascular endothelial growth factor expression by immunohistochemistry. The colonic expression of COX-2 at 24 h and that of phospho-NF-κB and phospho-CREB (peaking at 6 h) after colitis induction were consistently inhibited by both α,β-amyrin and dexamethasone.Conclusions and implications:
Systemic administration of α,β-amyrin exerted a marked and rapid inhibition of TNBS-induced colitis, related to the local suppression of inflammatory cytokines and COX-2 levels, possibly via inhibition of NF-κB and CREB-signalling pathways. Taken together, our data suggest a potential use of α,β-amyrin to control inflammatory responses in bowel disease. 相似文献68.
Primary breast cancer is the most common malignancy in women. Metastatic cancer to the breast is very rare. Colorectal cancers usually metastasize to the liver and the lung; other sites of metastasis from colon cancer are uncommon and are usually found in association with extensive liver and/or lung metastases. This is a report of a rare case of aggressive rectal cancer with metastasis to the breast without liver or lung metastases. 相似文献
69.
Sickle cell anemia patients have low erythropoietin levels for their degree of anemia 总被引:3,自引:1,他引:2
We have studied serum immunoreactive erythropoietin (SIE) levels in 28 patients with sickle cell anemia (SCA) without renal insufficiency and in 17 patients with nonhemoglobinopathy anemias of comparable severity using a sensitive radioimmunoassay procedure. An exponential relationship between SIE level and degree of anemia was noted in all patients. However, in nonhemoglobinopathy anemia, a sharp rise in the SIE level occurred as hemoglobin (Hb) levels fell below about 12 g/dL, whereas in sickle cell patients the increase was not marked until hemoglobin fell to about 9 g/dL. The response was more blunted in older SCA patients than in younger ones. A linear regression model relating SIE level to Hb level, presence/absence of SCA, and age explained 63% of the variation in SIE. We conclude that the serum erythropoietin levels in SCA increased at a lower hemoglobin concentration and are of a lower magnitude than that of the other anemias. 相似文献
70.