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IntroductionMonoclonal antibody therapy has been reported to be highly effective for preventing hospitalisation and severe cases in patients with Coronavirus Disease 2019 (COVID-19). However, since the drug is not readily available, it is important to rapidly and appropriately identify high-risk patients who can benefit most from therapy. Therefore, we designed a risk scoring system to identify at-risk COVID-19 patients in our region during the largest surge of COVID-19, from July to September 2021.MethodsAccording to the risk scores, confirmed COVID-19 patients were introduced to receive REGN-CoV-2 to our hospital by regional health centre from 18th August (Term 3). The primary outcome was the comparison of the number of hospitalisation and severe condition with other periods, the 4th wave (Term 1) and the early part of the 5th wave (Term 2) in Japan.ResultsDuring Term 3, 115 patients were stratified with the scoring system and administered REGN-COV-2. The number of hospitalisation vs severe cases were 60 (5.2%) vs 14 (1.2%), 8 (1.5%) vs 3 (0.6%) and 21 (1.2%) vs 2 (0.1%), in term 1, 2 and 3, respectively. Among those aged <60 years, compared with term 1, the relative risk of hospitalisation and severe condition were 0.25 (95% CI: 0.12–0.53) and 0.10 (95% CI: 0.01–0.80), respectively, in term 3. Drug adverse events were fever (3: 2.6%), headache (1: 0.9%) and neck rash (1: 0.9%), all events were resolved within 24 h wth no serious adverse event.ConclusionsThe administration of monoclonal antibody therapy using a risk scoring system significantly reduced the number of hospitalisation and disease severity of COVID-19 without any serious adverse events and avoided regional medical collapse.  相似文献   
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目的 在健康体检人群中筛查原发性胆汁性胆管炎(PBC)的特异性抗体,即抗线粒体抗体(AMA)-M2,以了解其流行率。方法 2012年5月~2014年12月我院体检中心血清样本18515例,采用ELISA行AMA-M2定量检测,同时收集肝功能生化指标。结果 在筛查的18515名体检者中,245例(1.3%)血清AMA-M2阳性,男性97名,女性148名,男女比例约为1:1.5,46~55岁年龄段阳性比例率为28.6%;12名AMA-M2阳性者同时伴有血清ALP水平升高,符合中国PBC诊断和治疗共识的诊断标准;54例高滴度AMA-M2抗体(>150U/ml)者血清ALP为(92.8±85.6 U/L),GGT水平为(84.3±118.5 U/L,显著高于191例低滴度组【分别为(67.7±38.3U/L)和(39.1±61.8U/L),P<0.05】。结论 健康体检人群血清AMA-M2抗体阳性并不少见,筛查AMA-M2抗体有助于早期识别PBC。  相似文献   
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《Molecular therapy》2022,30(3):1171-1187
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目的:探究铜绿假单胞菌Ⅵ型分泌系统VgrG1a蛋白的原核表达方法,并制备鼠源性和人鼠嵌合型单克隆抗体为抗铜绿假单胞菌感染提供了研究基础。方法:根据NCBI网站上查找到的VgrG1a序列合成重组质粒pET-21a-VgrG1a,转化大肠杆菌感受态细胞BL21(DE3)plysS进行诱导。通过免疫沉淀法和酶联免疫吸附实验(enzyme linked immunosorbent assay,ELISA)对诱导得到的重组蛋白进行表达、纯化和鉴定。用纯化后的VgrG1a重组蛋白免疫BALB/c小鼠,制备鼠源多克隆抗体,并利用ELISA方法测定小鼠血清抗体的效价和特异性。通过P3X63Ag8.653骨髓瘤细胞融合小鼠脾细胞制备杂交瘤细胞,再通过有限稀释法获得单克隆细胞。经多次ELISA筛选出能够稳定产出特异性抗体的细胞株。在公司测序后获得单克隆抗体的序列信息,并设计出含有此抗体的质粒,转染Expi293细胞,制备人源化单克隆抗体。结果:结果显示,实验成功构建了VgrG1a重组质粒,经探索在最佳表达诱导条件下(温度16℃,IPTG浓度0.5mM,诱导时间16小时),表达得到了重组蛋白VgrG1a,SDS-PAGE显示72kDa处重组蛋白浓度最高。检测制备的鼠源抗体在稀释到1/640000后效价仍较高,并且与目的蛋白能够能特异性的识别并结合。人鼠嵌合型单克隆抗体8A4F5对抗原VgrG1a亲和力高于鼠源单克隆抗体。结论:以上结果表明,该原核表达的重组蛋白具有良好的免疫原性,利用表达的重组蛋白制备的单克隆抗体具有较高的抗体效价和特异性,为进一步研究蛋白的结构与功能、研制相关的诊断试剂及疫苗提供了生物材料。  相似文献   
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《Molecular therapy》2022,30(5):1979-1993
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AIM: To describe the clinical characteristics and treatments associated with antibody positive optic neuropathies including anti-myelin oligodendrocyte glycoprotein (MOG) and anti-aquaporin 4 (AQP4), alongside diagnostic modalities, investigations, and outcomes. METHODS: A cross-sectional single-centre retrospective case series consisting of 16 patients including 12 anti-MOG positive patients and 4 anti-AQP4 positive patients. Each of these patients had clinical signs and symptoms of optic neuritis and consisted of all patients who had a positive blood antibody result in our centre. Clinical findings including presence of a relative afferent pupillary defect, colour vision and disc assessment were recorded. Structured clinical exam and multimodal imaging was undertaken sequentially on each. Optical coherence tomography (OCT) scanning was preformed to examine the correlation between ganglion cell layer (GCL) thickness and visual acuity (VA) at presentation and as a determinant of final visual outcome in both groups. Initial and long-term treatment is also summarised. RESULTS: A total of 16 patients were included in the study consisting of 12 anti-MOG and 4 anti-AQP4 positive patients. Nine of the 16 patients were female and the average age of onset was 29.2y in the MOG group and 42y in the AQP4 group. There was no statistically significant correlation (Pearson correlation) between GCL thickness and presenting and final VA [r(10)=0.081, P=0.08 and r(10)=0.089, P=0.34 respectively]. The same statistical analysis was performed for the correlation between retinal nerve fibre layer (RNFL) and VA and similar outcomes were observed [r(10)=0.04, P=0.22 and r(10)=0.09, P=0.04]. No correlation was seen for initial RNFL thickness and final visual outcome in this group either [r(2)=0.19, P=0.38]. Visual field testing and radiological findings for each group are described. CONCLUSION: No correlation between initial VA or RNFL and final visual outcome is identified. A broad range of visual field and radiographic findings are identified, a consensus on treatment of neuromyelitis optica spectrum disorders and anti-MOG positive optic neuropathies has yet to be accepted but initial high dose immunosuppression followed by low dose maintenance therapy is favoured.  相似文献   
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