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《Human immunology》2022,83(3):204-218
Antibodies against HLA antigens are ubiquitous in the sera of transplant patients. Analysis of anti-HLA antibodies specificity has gone through a long history of development using assays like agglutination and lymphocytotoxicity, which utilize lymphocytes, and flow cytometry, which utilize multiplex beads coupled with single antigens. Hundreds of HLA antigens are identified to date, and the realization that antibody reactivity against the antigens is multispecific presented difficulties in accurately defining antibody specificity. Although Cross Reacting Groups (CREG), describing cross reactivity among HLA antigens, were helpful with determining specificity, they proved to be inadequate for the highly sensitized patients. Amino acid sequencing and three-dimensional modeling of the HLA molecules significantly advanced our understating of the HLA antigens and their epitopes. Although sensitive assays for antibody testing advanced analysis, they unmasked additional specificities undetectable by traditional methods, and the presence of naturally occurring anti-HLA antibodies in sera further complicated analysis and underscored the need to understand antibody reactivity and their epitopes. Hundreds of HLA class-I and class-II epitopes were defined by the Tekasaki and Duquesnoy groups and their usefulness in organ transplants were further advanced by a great number of transplant centers. Alloantibody specificities, CREGs, and nondonor specific antigens (NDSA) are now explained by public epitopes  相似文献   
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ObjectivesThe purpose of this study was to assess the extent to which the association between premature dual antiplatelet therapy (DAPT) discontinuation and excess risk of thrombotic events varies according to the reason and timing of DAPT discontinuation and whether high on-treatment platelet reactivity (HPR) influences the risk of thrombotic events after premature DAPT discontinuation.BackgroundDAPT after percutaneous coronary intervention (PCI) suppresses platelet reactivity, and HPR on clopidogrel after PCI is associated with an increased risk of thrombotic events.MethodsADAPT-DES (Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents) was a prospective, multicenter registry of 8,582 patients successfully treated with coronary drug-eluting stents that assessed HPR on clopidogrel. For patients who discontinued aspirin or clopidogrel at any time during the study, the reasons for discontinuation were systematically categorized.ResultsPlanned DAPT discontinuation occurred within 2 years in 3,203 (37.3%) patients. One thousand four hundred eighteen (16.5%) patients discontinued DAPT for unplanned reasons, including surgery or trauma (n = 768 [8.9%]), patient nonadherence (n = 321 [3.7%]), bleeding complications (n = 264 [3.1%]), and drug allergy or hypersensitivity (n = 113 [1.3%]). Unplanned but not planned DAPT discontinuation was associated with an increased risk of a major adverse cardiac event (MACE, defined as the composite of cardiac death, myocardial infarction, or stent thrombosis); with highest risk within 3 months after PCI (adjusted HR: 7.65, 95% CI: 2.77-21.10 vs adjusted HR: 2.47, 95% CI: 1.70-3.58 for unplanned DAPT discontinuation ≥3 months after PCI). MACE risk after DAPT discontinuation was not moderated by HPR (Pinteraction = 0.91).ConclusionsIn this large-scale all-comers registry, premature DAPT discontinuation for unplanned reasons occurred in approximately 1 of 6 patients after DES implantation and was associated with a markedly increased risk of MACEs. (Assessment of Dual AntiPlatelet Therapy With Drug Eluting Stents [ADAPT-DES]; NCT00638794)  相似文献   
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Objectives: Suicide is best studied by deconstructing the psychological experiences preceding suicidal death. We assessed the characteristics of tedium vitae (feeling tired of life) after first ever stroke in Nigerian survivors.

Methods: Using the Schedule for Clinical Assessment in Neuropsychiatry, tedium vitae was assessed in 130 stroke survivors attending rehabilitation in a large Nigerian university hospital. Global cognitive and executive dysfunctions were evaluated, respectively, using the Mini Mental State Examination and the modi?ed Indiana University Token test. All participants had their index stroke 3 to 24 months before recruitment into the study. We also examined a comparative group of 130 age, gender, and education matched apparently normal persons who were unrelated to the stroke survivors. Associations were explored using univariate and multivariate logistic regression analyses.

Results: Tedium vitae was experienced by 16 (12.3%) stroke survivors compared with 5 (3.9%) in the comparative group (O. R = 3.5, 95% C. I = 1.3–9.9, p = 0.018). Among stroke survivors, those who were retired were more likely to experience tedium vitae (56.2%, p = 0.045). In analyses adjusting for the effect of systemic hypertension, cognitive dysfunction, retirement and marital separation, there was a 3.5-fold increase in the odds of experiencing tedium vitae after surviving a stroke (O. R = 3.5, 95% C. I = 1.1–11.6, p = 0.042).

Conclusions: Tedium vitae is a common suicidal experience after stroke and may be among the earliest perceptible pointer to impending poststroke suicide. It is easy to assess and may be less costly to obtain an adequate sample size in studies aiming to understand the phenomenon of suicide in the stroke population.  相似文献   

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缺血性脑血管病的梗死模式具有多样性,根据梗死数目可分为无梗死、单发梗死和多发 梗死。单发梗死主要根据病灶的位置和大小进行分类,多发梗死则根据血管的供血范围进行分类。 单发梗死和多发梗死的不同梗死模式分别与不同的病因和发病机制相关。  相似文献   
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