应用干细胞分离仪分离脐血与传统手工分离法的效果比较

目的:脐血处理的关键问题是提高干细胞的回收率及实现处理过程的标准化和可重复化,实验对此进行探讨,比较干细胞分离仪与传统羟乙基淀粉手工法分离脐血的效果。方法:实验于2006-12/2007-05在广州医学院附属市一人民医院完成。①脐血来源:39份脐血采自广州医学院附属市一人命医院妇产科健康顺产新生儿脐带,产妇均知情同意。随机数字表法分为仪器分离组17份、手工分离组22份。②实验方法:仪器分离组收集脐血称质量,计算体积,在开始处理前20min缓慢加入相当于20%脐血体积的60g/L羟乙基淀粉。仪器分离组按仪器要求自动分离,分离终体积20mL。手工分离组50g离心5min,压浆板压出全部血浆以及18mL红细胞移至无菌空袋,500g离心13min,自动压浆板压出血浆,保留20mL终体积样本。③实验评估:采用全自动计数仪进行检测有核细胞(白细胞)、红细胞数量。流式细胞仪分析CD34 含量。结果:采用干细胞分离仪处理浓缩脐血,有核细胞回收率为(89.7±3.4)%,CD34 细胞回收率为(98.8±5.1)%,红细胞去除率为(55.2±16.7)%,均比手工分离组分离效果好,差异有显著性意义(P<0.05或0.01)。同时,仪器分离组有核细胞回收率、CD34 细胞回收率的标准差均明显低于手工分离组(3.4vs.15.3;5.1vs.10.3)。结论:相比传统的羟乙基淀粉手工分离法,干细胞分离仪脐血分离浓缩效果理想,且结果标准误小,数据稳定。     

肺泡膜弥散和肺毛细血管血量特征在不同级别慢性阻塞性肺病患者的表现

目的:了解不同级别慢性阻塞性肺病患者肺泡毛细血管膜弥散量和肺泡毛细血管血量的特点。方法:收集2006-07/2007-03就诊于四川大学华西医院呼吸科的慢性阻塞性肺病患者154例,依据慢性阻塞性肺病方案分级,0级64例,Ⅰ级38例,Ⅱ级26例,Ⅲ和Ⅳ级共26例。行肺通气功能、肺容量、一氧化碳弥散量、肺泡毛细血管膜弥散量和肺泡毛细血管血量测定。结果:154例患者均进入结果分析。①0级与I级慢性阻塞性肺病患者,无论一氧化碳弥散量、肺泡毛细血管膜弥散量和肺泡毛细血管血量都正常。随着慢性阻塞性肺病程度加重,一氧化碳弥散量、肺泡毛细血管膜弥散量和肺泡毛细血管血量均有不同程度降低。Ⅱ级慢性阻塞性肺病时一氧化碳弥散量和肺泡毛细血管膜弥散量下降明显,肺泡毛细血管血量改变不明显。其中肺泡毛细血管膜弥散量出现异常明显早于一氧化碳弥散量和肺泡毛细血管血量,而且较严重。Ⅲ和Ⅳ级慢性阻塞性肺病的肺泡毛细血管血量下降明显。②一氧化碳弥散量、肺泡毛细血管膜弥散量和肺泡毛细血管血量与慢性阻塞性肺病级别、残气量/肺总量成负相关,与第1秒用力呼气容积/用力肺活量和第1秒用力呼气容积占预计值百分比成正相关,而且,肺泡毛细血管膜弥散量与各指标的相关性最好。结论:随着慢性阻塞性肺病程度的加重,一氧化碳弥散量、肺泡毛细血管膜弥散量和肺泡毛细血管血量均有下降。肺泡毛细血管膜弥散量的异常比一氧化碳弥散量和肺泡毛细血管血量较早出现而且较严重。肺泡毛细血管膜弥散量的测定可以监测疾病发展并早期发现慢性阻塞性肺病气体交换的异常。     

Incidence and risk factors of acute kidney injury in COVID-19 patients with and without acute respiratory distress syndrome (ARDS) during the first wave of COVID-19: a systematic review and Meta-Analysis

BackgroundAcute kidney injury (AKI) is common among patients with COVID-19. However, AKI incidence may increase when COVID-19 patients develop acute respiratory distress syndrome (ARDS). Thus, this systematic review and meta-analysis aimed to assess the incidence and risk factors of AKI, need for kidney replacement therapy (KRT), and mortality rate among COVID-19 patients with and without ARDS from the first wave of COVID-19.MethodsThe databases MEDLINE and EMBASE were searched using relevant keywords. Only articles available in English published between December 1, 2019, and November 1, 2020, were included. Studies that included AKI in COVID-19 patients with or without ARDS were included. Meta-analyses were conducted using random-effects models.ResultsOut of 618 studies identified and screened, 31 studies met the inclusion criteria. A total of 27,500 patients with confirmed COVID-19 were included. The overall incidence of AKI in patients with COVID-19 was 26% (95% CI 19% to 33%). The incidence of AKI was significantly higher among COVID-19 patients with ARDS than COVID-19 patients without ARDS (59% vs. 6%, p < 0.001). Comparing ARDS with non-ARDS COVID-19 cohorts, the need for KRT was also higher in ARDS cohorts (20% vs. 1%). The mortality among COVID-19 patients with AKI was significantly higher (Risk ratio = 4.46; 95% CI 3.31–6; p < 0.00001) than patients without AKI.ConclusionThis study shows that ARDS development in COVID-19-patients leads to a higher incidence of AKI and increased mortality rate. Therefore, healthcare providers should be aware of kidney dysfunction, especially among elderly patients with multiple comorbidities. Early kidney function assessment and treatments are vital in COVID-19 patients with ARDS.     

骨髓间充质干细胞移植对急性心肌梗死大鼠血管内皮功能的影响

目的:观察骨髓间充质干细胞移植治疗急性心肌梗死对血管内皮功能的影响。方法:实验于2005-09/2006-06在唐山工人医院中心实验室完成。①选用清洁级健康近交系SD大鼠40只,随机数字表法分为假手术组、模型对照组、干细胞移植组、细胞培养基组,10只/组。另取1只大鼠用于骨髓间充质干细胞的提取。②大鼠处死后无菌条件下分离股骨和胫骨,剔除肌肉、骨膜,剪一侧骨端,用10mL无血清DMEM低糖培养基冲出骨髓细胞后,收集冲洗液制成单细胞悬液,过滤离心,弃上清液,密度梯度法分离培养骨髓间充质干细胞。待细胞80%贴满培养瓶底时,用乙二胺四乙酸和胰蛋白酶混合消化传代。将4,6-二脒-2-苯基吲哚以50mg/L浓度加入第3代细胞培养基中,制成细胞悬液备用。③术前各组大鼠均行气管插管,建立急性心肌梗死模型,以远端供血区心肌组织颜色苍白、心电图检测Ⅱ导联ST段持续抬高为模型建立成功的标志。假手术组仅开胸予以前降支穿线但不结扎。④造模成功后1～3h,干细胞移植组用微量注射器吸取4,6-二脒-2-苯基吲哚标记好的第3代骨髓间充质干细胞悬液50μL,直接注入梗死区边缘的心肌组织。细胞培养基组按干细胞移植组的方法于相同部位注射等量无血清DMEM低糖培养基(pH值6.9)。⑤造模后4周处死各组大鼠,切取心脏组织,于梗死边缘区心肌组织制作切片,荧光显微镜下观察4,6-二脒-2-苯基吲哚标记的供体细胞。留取2mL全血,离心后抽取血清500μL,酶联免疫吸附法测定血清中细胞间黏附分子1与血管内皮细胞黏附分子1的含量。结果:40只大鼠均进入结果分析。①体外培养骨髓间充质干细胞的性状观察:从正常大鼠骨髓中分离培养的原代骨髓间充质干细胞,24～48h贴壁生长,短棒状;7～10d达到80%～90%融合;传至第3代骨髓间充质干细胞分布均匀,呈纺锤形。②各组心脏标本4,6-二脒-2-苯基吲哚标记移植细胞的存活状况:干细胞移植组可见成团及散在的4,6-二脒-2-苯基吲哚标记的阳性细胞,其余3组心脏标本中均未见荧光细胞。③各组大鼠血清中细胞间黏附分子1与血管内皮细胞黏附分子1的含量检测:与假手术组比较,模型对照组、细胞培养基组、干细胞移植组细胞间黏附分子1与血管内皮细胞黏附分子1的含量均明显升高(P<0.01或0.05);与模型对照组比较,干细胞移植组细胞间黏附分子1与血管内皮细胞黏附分子1的含量均有所降低[(3.37±0.14),(2.10±0.15)μg/L;(2.64±0.13),(1.74±0.06)μg/L;P均<0.05]。结论:骨髓间充质干细胞移植到实验性大鼠心肌梗死模型后成功存活,能降低血清中增高的细胞间黏附分子1与血管内皮细胞黏附分子1含量,提示骨髓间充质干细胞移植可能通过降低黏附分子的表达来改善血管内皮功能。