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11.
The authors studied the natural history of human immunodeficiency virus (HIV) exposure in 187 hemophiliacs followed for an average of 45 months. Overall, 55 percent developed antibody specific for HIV and 21 percent developed persistent generalized lymphadenopathy. Most patients seroconverted sometime between early 1982 and the end of 1984. Four patients developed acquired immune deficiency syndrome (AIDS) and four seropositive patients developed idiopathic thrombocytopenia (ITP). One of the four patients who developed AIDS and three of the four with ITP had preexisting lymphadenopathy. None of the 10 patients with lymphadenopathy or the 20 asymptomatic patients was seropositive for human T-lymphotropic virus, type I. Although seropositivity and lymphadenopathy have been found in many of the authors' patients, few have developed clinical disease that can be related to HIV infection.  相似文献   
12.
Adverse reactions in blood donors with a history of seizures or epilepsy   总被引:1,自引:0,他引:1  
BACKGROUND: Individuals with epilepsy or seizure disorders are restricted from donating blood because of concern that they are prone to adverse donor reactions such as syncope and convulsions. A study evaluating whether that concern is warranted is reported. STUDY DESIGN AND METHODS: During a 2-year period beginning in 1987, blood donors in Maryland with a history of seizures were actively recruited by the American Red Cross. Adverse donor reactions were classified as "slight", indicating dizziness and nausea without loss of consciousness; "moderate," denoting syncope; and "severe," indicating convulsive syncope. RESULTS: There were 329,143 satisfactory blood donations; 613 individuals reporting a history of seizures donated blood a total of 723 times. Among donors with seizures, 186 (35.7%) were taking antiepileptic medication, and 61 (8.4%) had had one or more seizures in the preceding year. Individuals with seizures had a low incidence of adverse reactions (3.34%). Although this incidence was slightly higher than that in the entire population (2.24%), the difference was not significant. In particular, the risk of syncope with or without convulsive activity was low for people with seizures (0.21%) and not significantly greater than that in other donors (0.28%). CONCLUSION: Individuals with seizures or epilepsy are not at greater risk for adverse reactions after blood donation, and major restrictions on their participation as blood donors are not warranted.  相似文献   
13.
Objective:  Hutchinson-Gilford progeria syndrome (HGPS) is a rare early-onset accelerated senescence syndrome. In HGPS, a recently identified de novo dominant mutation of the lamin A gene ( LMNA ) produces abnormal lamin A, resulting in compromised nuclear membrane integrity. Clinical features include sclerotic skin, cardiovascular and bone abnormalities, and marked growth retardation. Craniofacial features include 'bird-like' facies, alopecia, craniofacial disproportion, and dental crowding. Our prospective study describes dental, oral soft tissue, and craniofacial bone features in HGPS.
Methods:  Fifteen patients with confirmed p.G608G LMNA mutation (1–17 years, seven males, eight females) received comprehensive oral evaluations. Anomalies of oral soft tissue, gnathic bones, and dentition were identified.
Results:  Radiographic findings included hypodontia ( n  = 7), dysmorphic teeth ( n  = 5), steep mandibular angles ( n  = 11), and thin basal bone ( n  = 11). Soft tissue findings included ogival palatal arch ( n  = 8), median sagittal palatal fissure ( n  = 7), and ankyloglossia ( n  = 7). Calculated dental ages (9 months to 11 years 2 months) were significantly lower than chronological ages (1 year 6 months to 17 years 8 months) ( P  = 0.002). Eleven children manifested a shorter mandibular body, anterior/posterior cranial base and ramus, but a larger gonial angle, compared to age/gender/race norms.
Conclusion:  Novel oral-craniofacial phenotypes and quantification of previously reported features are presented. Our findings expand the HGPS phenotype and provide additional insight into the complex pathogenesis of HGPS.  相似文献   
14.
From experiments with purified proteins, it has been concluded that factor XIa (FXIa) is inhibited in plasma mainly by alpha 1-antitrypsin (a1AT), followed by antithrombin III (ATIII), C1-inhibitor (C1Inh), and alpha 2-antiplasmin (a2AP). However, the validity of this concept has never been studied in plasma. We established the relative contribution of different inhibitors to the inactivation of FXIa in human plasma, using enzyme-linked immunosorbent assays (ELISAs) for the quantification of complexes of FXIa with a1AT, C1Inh, a2AP, and ATIII. We found that 47% of FXIa added to plasma formed complexes with C1Inh, 24.5% with a2AP, 23.5% with a1AT, and 5% with ATIII. The distribution of FXIa between these inhibitors in plasma was independent of whether FXIa was added to plasma, or was activated endogenously by kaolin, celite, or glass. However, in the presence of heparin (1 or 50 U/mL), C1Inh appeared to be the major inhibitor of FXIa, followed by ATIII. Furthermore, at lower temperatures, less FXIa-C1Inh and FXIa-a1AT complexes but more FXIa-a2AP complexes were formed. These data demonstrate that the contribution of the different inhibitors to inactivation of FXIa in plasma may vary, but C1Inh is the principal inhibitor under most conditions.  相似文献   
15.
目的 探讨多房棘球绦虫(Em)重组BCG-EmⅡ/3疫苗免疫和Em原头节攻击后小鼠脾细胞因子的变化.方法 将Balb/c小鼠按体质量随机分为3组:疫苗皮下注射组、疫苗鼻腔内接种组、对照组.免疫后8周用Em原头节进行攻击感染,感染后18周杀鼠取脾,分离脾细胞,分别用原液、Em抗原(EmAg)、刀豆蛋白A(ConA)或植物血凝素(PHA)培养,酶联免疫吸附(ELISA)法检测脾细胞培养上清液中白细胞介素2(IL-2)、γ干扰素(IFN-γ)、肿瘤坏死因子α(TNF-β)、白细胞介素4(IL-4)水平.结果 疫苗皮下注射组原液培养条件下IL-2、IFN-γ、TNF-α和IL-4水平分别为(34.6±2.7)、(34.5±2.8)、(265.0±0.0)、(9.8±2.6)ng/L,与对照组[(25.0±1.9)、(30.0±0.0)、(10.0±0.0)、(12.5±2.7)ng/L]比较差异均有统计学意义(P<0.01或<0.05);疫苗鼻腔内接种组原液培养条件下上述4种指标分别为(32.5±2.2)、(33.6±2.7)、(130.0±0.0)、(10.4±2.7)ng/L.与对照组比较差异均有统计学意义(P<0.01或<0.05);疫苗皮下注射组原液培养条件下TNF-α水平明显高于疫苗鼻腔内接种组(P<0.01).EmAg、ConA(或PHA)刺激培养条件下,上述4种指标明显高于相同组别的原液培养(P<0.01),且ConA(或PHA)刺激培养条件下,上述4种指标明显高于相同组别的EmAg刺激培养条件(P<0.01).结论 多房棘球绦虫重组BCG-EmⅡ/3疫苗诱导小鼠产生辅助T淋巴细胞(Th)1型免疫反应,从而对抗Em原头节攻击感染.  相似文献   
16.
HLA-identical bone marrow transplantation (BMT) may be complicated by graft-versus-host disease or graft rejection. Both complications are thought to be initiated by recognition of minor histocompatibility (mH) antigens by HLA-restricted mH-antigen-specific T lymphocytes. Using HLA- A2-restricted mH antigens HA-1-, -2-, and -4-, and HY-specific cytotoxic T lymphocyte (CTL) clones, we studied the recognition by these CTL clones of interleukin-2 (IL-2)-stimulated T cells (IL-2 blasts), BM mononuclear cells (BMMNCs), and hematopoietic progenitor cells (HPCs). We showed that, when IL-2 blasts from the BM donors who were investigated were recognized by the HA-1-, -2-, and -4-, and HY- specific CTL clones, their BMMNCs and HPCs were recognized as well by these CTL clones, resulting in antigen-specific growth inhibition of erythrocyte burst-forming units (BFU-E), colony-forming units- granulocyte (CFU-G), and CFU-macrophage (CFU-M). the HA-2-specific CTL clone, however, inhibited BFU-E and CFU-G growth from four donors to a lesser extent than from two other donors. We further investigated whether inhibitory cytokines released into the culture medium by the antigen-specific stimulated CTLs or by stimulated BMMNCs were responsible for suppression of HPC growth or whether this effect was caused by direct cell-cell contact between CTLs and HPCs. HPC growth inhibition was only observed after preincubation of BMMNCs and CTLs together for 4 hours before plating the cells in semisolid HPC culture medium. When no cell-cell contact was permitted before plating, neither antigen-stimulated CTL nor antigen-nonstimulated CTLs provoked HPC growth inhibition. Culturing BMMNCs in the presence of supernatants harvested after incubation of BMMNCs and CTL clones together for 4 or 72 hours did also not result in HPC growth inhibition. Both suppression of HPC growth and lysis of IL-2 blasts and BMMNCs in the 51Cr-release assay appeared to be dependent on direct cell-cell contact between target cells and CTLs and were not caused by the release of inhibitory cytokines into the culture medium by antigen-specific stimulated CTLs or by stimulated BMMNCs. Our results show that mH-antigen-specific CTLs can inhibit HPC growth by a direct cytolytic effect and may therefore be responsible for BM graft rejection after HLA-identical BMT.  相似文献   
17.
18.
deShazo  RD; Daul  CB; Andes  WA; Bozelka  BE 《Blood》1985,66(4):993-998
Over an average span of one year, we performed a prospective clinical and immunologic evaluation of 30 patients with hemophilia. No patient developed life-threatening opportunistic infection or malignancy; however, the immunologic abnormalities and lymphadenopathy initially present in nine patients (lymphadenopathy group) persisted. In addition, five patients, representing 24% of the initial group without lymphadenopathy, developed generalized lymphadenopathy (converter group). One episode of idiopathic thrombocytopenia (ITP) and one episode of staphylococcal sepsis occurred in this "converter" group; one episode of ITP also occurred in the lymphadenopathy group. Sixteen patients remained asymptomatic. At the time of the follow-up evaluation, those differences in mononuclear cell (MNC) percentages and numbers noted initially among the three hemophiliac groups were no longer present. Natural killer cell function alone or in the presence of biologic response modifiers was not different among hemophiliac and control groups. Before developing lymphadenopathy, the converter group of patients had significantly better lymphocyte mitogenic function than did the other two groups of patients with hemophilia. However, lymphocyte mitogenic responses of all groups of patients with hemophilia significantly deteriorated over the course of the study. The abnormal mitogenic responses noted in these patients was explained in part by higher levels of spontaneous suppressor cell activity in mononuclear cell preparations from patients with hemophilia. We conclude that long-term immunologic studies of this patient population requires both quantitative and qualitative evaluations. Our data show that patients with hemophilia have progressive dysfunction of cell- mediated immunity.  相似文献   
19.
High-field surface coil magnetic resonance (MR) images were obtained of 12 ankles: two from healthy volunteers, seven from patients, and three from fresh cadavers. The cadaver ankles were sectioned in the coronal, sagittal, and axial planes for direct comparison with the MR images. Plain film confirmation of pathologic conditions was obtained in all patients, and five underwent arthroscopy or surgery, or both. MR imaging provided excellent delineation of ligaments and cartilaginous structures in all cases.  相似文献   
20.
Kniep  B; Flegel  WA; Northoff  H; Rieber  EP 《Blood》1993,82(6):1776-1786
Monoclonal CDw60 antibodies recognize glycolipid antigens with restricted surface expression on human leukocytes. They allow us to define new functional subpopulations of T lymphocytes and are able to induce costimulatory signals. In this report, we describe the molecular composition of CDw60 glycolipid antigens derived from different human leukocyte subpopulations. The glycolipids were isolated and their structures were identified by immunochemical methods. All molecules containing the CDw60 determinant were found in the disialoganglioside fraction. They were O-acetylated derivatives of the gangliosides II3 (Neu5Ac)2-LacCer (GD3), IV3 (Neu5Ac)2-nLc4Cer (DSPG), and VI3 (Neu5Ac)2- nLc6Cer (DSnHC), respectively. The most common CDw60 glycolipid antigen in human leukocytes was 9-O-acetyl GD3. In a comparison of various cell types, the highest concentration of 9-O-acetyl GD3 on a per cell basis was determined in granulocytes and in blood T lymphocytes, whereas B lymphocytes, thymus cells, and monocytes contained considerably smaller amounts of this molecule. Polar CDw60 antigens such as 9-O-acetyl DSPG and 9-O-acetyl DSnHC were only detected in granulocytes.  相似文献   
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