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1.
《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   
2.
ObjectivesThis study was conducted to compare the healing response of localized gingival recession defects treated with a coronally advanced flap (CAF) and either an amnion allograft membrane (AM) or a connective tissue graft (CTG).MethodsGingival recession defects were surgically created in six healthy mongrel dogs at the labial root surface of the maxillary canines, bilaterally. Using a split mouth design, the defects were treated with CAF and either AM (CAF/AM) or CTG (CAF/CTG). Three animals for each group were scarified at 1 and 3 months. Segments containing the defects were prepared for histological and histometric analysis.ResultsBoth techniques showed similar clinical findings with adequate root coverage. Histologically, healing was characterized by the formation of new cementum and new connective tissue attachment in the CAF/AM group; in the CAF/CTG group, healing was characterized by junctional epithelium, coronally, and connective tissue fibers parallel to the root surface, apically. Histometrically, the CAF/AM group revealed a substantially shorter epithelial length and a longer, new cementum compared with those of the CAF/CTG group after a healing period of 3 months.ConclusionsWithin the limits of this study, we concluded that the AM allograft could promote periodontal healing in gingival recession defects.  相似文献   
3.
目的探究老年2型糖尿病(T2DM)并阻塞性睡眠呼吸暂停综合征(OSAS)患者25羟基维生素D[25(OH)D]和血小板参数[平均血小板体积(MPV)和血小板分布宽度(PDW)]变化及与OSAS严重程度的相关性。方法选择2016年10月—2021年10月于宁德师范学院附属宁德市医院诊治的61例老年T2DM合并OSAS患者为观察组,50例单纯T2DM患者为对照组。观察并比较2组基线资料及血25(OH)D、MPV、PDW水平,以及OSAS严重程度不同的患者25(OH)D、MPV和PDW水平,采用Logistic回归模型分析OSAS的影响因素。结果 2组BMI、高血压史、冠心病史、糖化血红蛋白(HbA1c)、高密度脂蛋白胆固醇(HDL-C)和尿酸(UA)差异具有统计学意义(P<0.05);观察组MPV和PDW显著高于对照组(P<0.05),25(OH)D低于对照组(P<0.05);OSAS严重程度不同的患者间25 (OH)D和血小板参数差异具有统计学意义(P<0.05),其中25(OH)D随着OSAS严重程度的增高而降低(P<0.05),MPV、PDW随着OSAS严重程度的增高而上升(P<0.05);Logistic回归分析结果显示,冠心病史、HbA1c、25(OH)D、MPV和PDW是OSAS发生的影响因素(P<0.05)。结论老年T2DM合并OSAS患者MPV和PDW变化呈现上升趋势,25(OH)D呈下降趋势,其水平变化与T2DM合并OSAS发生和病情关系密切。  相似文献   
4.
Background and aimsAlthough antithrombotic treatments are established for coronary artery disease (CAD), they increase the bleeding risk, especially in malnourished patients. The total thrombus-formation analysis system (T-TAS) is useful for the assessment of thrombogenicity in CAD patients. Here, we examined the relationships among malnutrition, thrombogenicity and 1-year bleeding events in patients undergoing percutaneous coronary intervention (PCI).Methods and resultsThis was a retrospective analysis of 300 consecutive CAD patients undergoing PCI. Blood samples obtained on the day of PCI were used in the T-TAS to compute the thrombus formation area under the curve. We assigned patients to two groups based on the geriatric nutritional risk index (GNRI): 102 patients to the lower GNRI group (≤98), 198 patients to the higher GNRI group (98<). The primary endpoint was the incidence of 1-year bleeding events defined by Bleeding Academic Research Consortium criteria types 2, 3, or 5. The T-TAS levels were lower in the lower GNRI group than in the higher GNRI group. Kaplan-Meier analysis showed worse 1-year bleeding event-free survival in the lower GNRI group compared with the higher GNRI group. The combined model of the GNRI and the Academic Research Consortium for High Bleeding Risk (ARC-HBR) had good calibration and discrimination for bleeding risk prediction. In addition, having a lower GNRI and ARC-HBR positivity was associated with 1-year bleeding events.ConclusionA lower GNRI could reflect low thrombogenicity evaluated by the T-TAS and determine bleeding risk in combination with ARC-HBR positivity.  相似文献   
5.
目的评估肝脏瞬时弹性成像、天冬氨酸转氨酶与血小板比值指数(APRI)及基于4因子的肝纤维化指数(FIB-4)对儿童非酒精性脂肪性肝病(NAFLD)肝纤维化的诊断价值。方法选取湖南省儿童医院2015年8月至2020年10月已行肝穿刺病理活检的非酒精性脂肪性肝病100例进行回顾性研究,收集肝脏病理组织和临床资料。采用受试者操作特征曲线(ROC曲线)分析肝脏硬度(LSM)值、APRI及FIB-4诊断儿童NAFLD所致不同肝脏纤维化的诊断价值。结果LSM值、APRI、FIB-4诊断肝纤维化(S≥1)的ROC曲线下面积(AUC)分别为0.701[95%可信区间(CI):0.579~0.822,P=0.011]、0.606(95%CI:0.436~0.775,P=0.182)、0.568(95%CI:0.397~0.740,P=0.387),最佳临界值分别为6.65 kPa、21.20、0.18;LSM值、APRI、FIB-4诊断显著肝纤维化(S≥2)的AUC分别为0.660(95%CI:0.552~0.768,P=0.006)、0.578(95%CI:0.464~0.691,P=0.182)、0.541(95%CI:0.427~0.655,P=0.482),最佳临界值分别为7.35 kPa、24.78、0.22;LSM值、APRI、FIB-4诊断进展期肝纤维化(S≥3)的AUC分别为0.639(95%CI:0.446~0.832,P=0.134)、0.613(95%CI:0.447~0.779,P=0.223)、0.587(95%CI:0.411~0.764,P=0.346),最佳临界值分别为8.55 kPa、26.66、0.27。结论瞬时弹性成像技术对儿童NAFLD肝纤维化有较好的诊断价值,优于APRI和FIB-4。  相似文献   
6.
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   
7.
Aim of the workTo evaluate hematologic parameters in patients with primary Sjögren's syndrome (PSS) and their association with disease activity.Patients and methodsSixty-five PSS patients and 65 age and sex matched control were studied. Neutrophil to lymphocyte ratio (NLR), mean platelet volume (MPV), red blood cells distribution width (RDW), platelet to lymphocyte ratio (PLR) and platelet count were evaluated. The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were measured. The European league against rheumatism (EULAR) Sjögren's syndrome disease activity index (ESSDAI) was assessed.ResultsThe mean age of patients was 47.8 ± 12.1 years and disease duration 5.71 ± 1.2 years and they were 63 females and 2 males. The mean ESSDAI was 6.4 ± 7.9 (3–25). 11 had neurological involvement. 92.3% of patients received low-dose prednisolone (<10 mg/day) and hydroxychloroquine (HCQ). The mean NLR (1.83 ± 0.8), PLR (131.9 ± 32.5) and MPV (8.82 ± 1.4) in patients was significantly higher than in control (NLR 1.57 ± 0.56, PLR 109.9 ± 24.7 and MPV 7.71 ± 1.3; p = 0.036, p < 0.001 and p < 0.001 respectively). The RDW tended to be higher in patients (13 ± 1.56) compared to control (12.83 ± 1.13) (p = 0.46). There was a significant correlation between ESSDAI with NLR (r = 0.29, p = 0.02), RDW (r = 0.37, p = 0.002), ESR (r = 0.32, p = 0.01) and CRP (r = 0.33, p = 0.007) and between MPV with CRP (r = 0.27, p = 0.03) and between RDW and ESR (r = 0.36, p = 0.003).On regression analysis, NLR and RDW were significant predictors of disease activity (p = 0.01 and p = 0.02 respectively).ConclusionThe MPV, PLR and NLR, were significantly increased in PSS. NLR and RDW can be used as indicators of disease activity.  相似文献   
8.
目的 探讨超活化血小板裂解液(sPL)对类风湿关节炎患者成纤维细胞样滑膜细胞(RA-FLS)的影响。方法 选取哈尔滨医科大学附属第一医院2018年1月—2019年3月6例类风湿关节炎患者作为研究对象,其中男3例、女3例,年龄26~49岁、中位年龄33岁,受累关节功能分级均为Ⅱ级。收集患者静脉血标本,先进行两次离心分离获得富血小板血浆(PRP);再加入0.08 mmol/L CaCl2, 37 ℃孵育激活血小板;然后经过冷冻、融化、离心、过滤除菌、去除纤维蛋白原,获得sPL。培养RA-FLS,分为对照组和2.5%、5%、10% sPL组,分别与含有0、2.5%、5%、10% sPL的培养液培养48 h。采用酶联免疫吸附试验(ELISA)检测各组细胞中炎症因子白细胞介素(IL)-6、肿瘤坏死因子(TNF)-α、IL-1β的浓度;细胞计数试剂盒(CCK)-8法测定各组细胞增殖活性;流式细胞术测定各组细胞的凋亡率;体外小管生成实验检测各组细胞血管生成能力;Transwell实验检测各组细胞迁移能力和侵袭能力;Western blot法测定各组细胞增殖细胞核抗原(PCNA)、细胞周期蛋白D1(CyclinD1)、B细胞淋巴瘤/白血病-2蛋白(Bcl-2)、Bcl-2相关X蛋白(Bax)、基质金属蛋白酶(MMP)2、MMP-9、血管内皮生长因子(VEGF)和VEGF受体-2 (VEGFR2)的表达情况。结果 (1)对照组、2.5%sPL组、5%sPL组、10%sPL组细胞培养基中IL-6浓度分别为(80.18±11.67)、(59.94±9.50)、(46.60±8.04)、(60.67±9.24)pg/mL,TNF-α浓度分别为(70.75±9.14)、(54.56±7.81)、(43.27±6.30)、(53.99±8.60)pg/mL,IL-1β浓度分别为(64.18±9.90)、(46.97±8.79)、(36.28±7.44)、(47.66±8.15)pg/mL,组间比较差异均有统计学意义(F=12.186、11.934、10.709,P值均<0.01);2.5%sPL组、5%sPL组、10% sPL组细胞中IL-6、TNF-α、IL-1β的表达水平均明显低于对照组,差异均有统计学意义(P值均<0.05);5% sPL组炎症因子表达水平低于2.5% sPL组和10% sPL组,差异均有统计学意义(P值均<0.05)。(2)对照组、2.5%sPL组、5%sPL组、10%sPL组RA-FLS增殖率分别为87.33%±10.98%、76.17%±8.18%、60.83%±7.99%、75.83%±8.45%,细胞凋亡率分别为6.51%±1.16%、16.23%±2.75%、29.69%±3.80%、16.37%±2.29%,小管形成数分别为(41.00±7.55)、(26.67±4.16)、(11.67±3.51)、(26.00±6.56)个,迁移细胞数目分别为(443.00±54.06)、(282.33±31.66)、(154.64±23.18)、(292.00±35.03)个,侵袭细胞数目分别为(243.30±27.39)、(67.00±12.53)、(22.33±8.74)、(79.33±14.98)个,组间比较差异均有统计学意义(F=8.795、38.095、34.278、29.352、94.772, P值均<0.05);2.5%sPL组、5%sPL组、10% sPL组RA-FLS细胞增殖率、血管管腔形成数量、迁移细胞数目和侵袭细胞数目均低于对照组,细胞凋亡率均高于对照组,差异均有统计学意义(P值均<0.05);5% sPL组中细胞增殖率、小管形成数、迁移细胞数目和侵袭细胞数目均明显低于2.5% sPL组和10% sPL组,细胞凋亡率则高于2.5% sPL组和10% sPL组,差异均有统计学意义(P值均<0.05)。(3)对照组、2.5%sPL组、5%sPL组、10%sPL组RA-FLS PCNA、CyclinD1、Bax、Bcl-2、MMP-2、MMP-9、VEGF和VEGFR2蛋白相对表达量比较,差异均有统计学意义(P值均<0.01);2.5%sPL组、5%sPL组、10% sPL组细胞中PCNA、CyclinD1、Bcl-2、MMP-2、MMP-9、VEGF和VEGFR2蛋白相对表达量均低于对照组,Bax蛋白相对表达量均高于对照组,差异均有统计学意义(P值均<0.05);5% sPL组PCNA、CyclinD1、Bcl-2、MMP-2、MMP-9、VEGF和VEGFR2蛋白相对表达量均低于2.5% sPL组和10% sPL组,而Bax蛋白相对表达量则高于2.5% sPL组和10% sPL组,差异均有统计学意义(P值均<0.05)。结论 sPL对RA-FLS的增殖、迁移、侵袭、血管生成以及炎症因子的产生具有抑制作用,对RA-FLS凋亡具有促进作用,且SPL对RA-FLS的生长抑制效果与SPL浓度有关。  相似文献   
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