人白细胞介素-6受体胞外区配基结合功能域活性部位的三维构效关系

以人生长激素受体(K52-L251)的晶体结构为模板, 同源模建人白细胞介素-6受体(hIL-6R) (V106-P322)的空间结构, 并预测与配基(IL-6)结合的活性部位. 根据hIL-6R配基结合功能域中重要氨基酸点突变对活性部位空间构象的影响, 验证预测部位的正确性. 理论分析表明, hIL-6R配基结合功能域中4个保守的半胱氨酸(Cys), 近膜侧193位Cys及"WSEWS"主型框架的点突变均导致受体与配基的结合受阻;而211位Cys, 277位Cys点突变却有利于受体与配基的结合. 研究结果提示, 预测的hIL-6R的活性部位确是hIL-6R和配基(IL-6)结合的分子基础, 可以作为进行小分子hIL-6R拮抗剂设计的靶部位.     

HIV/AIDS患者抗病毒治疗前HIV-1耐药情况调查及外周血CD8+T细胞CD38表达水平研究

摘要 目的：分析人免疫缺陷病毒/艾滋病（HIV/AIDS）患者抗病毒治疗前HIV-1耐药以及影响因素,探讨HIV/AIDS患者外周血CD₈⁺T细胞CD₃₈表达（CD₈⁺CD₃₈⁺T淋巴细胞百分比）与CD₄⁺T淋巴细胞计数的相关性。方法：选择2016年3月至2019年12月我院接诊的442例HIV/AIDS患者（HIV/AIDS组）和163例同期于我院进行体检的健康志愿者（对照组）,HIV/AIDS组扩增pol基因,进行HIV-1基因耐药分析,检测CD₈⁺CD₃₈⁺T淋巴细胞百分比、CD₄⁺T淋巴细胞计数、CD₈⁺T淋巴细胞计数。分析HIV/AIDS患者HIV-1耐药的影响因素,分析CD₈⁺CD₃₈⁺T淋巴细胞百分比与CD₄⁺T淋巴细胞计数、CD₈⁺T淋巴细胞计数相关性。结果：HIV/AIDS组442例HIV/AIDS患者中376例获得HIV-1 pol基因序列,HIV-1耐药35例,耐药率9.31%（35/376）。单因素分析结果显示耐药组和非耐药组在年龄、文化程度、感染途径、HIV病毒载量方面差异有统计学意义（P＜0.05）。多因素Logistic回归分析结果显示同性性传播、注射吸毒、高HIV病毒载量是HIV/AIDS患者抗病毒治疗前HIV-1耐药的危险因素（P＜0.05）。HIV/AIDS组外周血CD₄⁺T淋巴细胞计数、CD₈⁺T淋巴细胞计数低于对照组（P＜0.05）,CD₈⁺CD₃₈⁺T淋巴细胞百分比高于对照组（P＜0.05）。CD₈⁺CD₃₈⁺T淋巴细胞百分比与CD₄⁺T淋巴细胞计数、CD₈⁺T淋巴细胞计数呈负相关（P＜0.05）。结论：抗病毒治疗前HIV/AIDS患者存在一定HIV-1耐药率,传播途径、HIV-1病毒载量与HIV-1耐药有关。CD₈⁺T细胞表面CD₃₈过表达与HIV/AIDS 患者CD₄⁺T T细胞的过度消耗有关。     

人白介素6受体结合功能域的构效关系研究

以分子对接（docking）方法研究人白介素6受体胞外区配基结合功能域“WSXWS”区氨基酸残基定点突变对受体与配基人白介素6结合时的相互作用能量、分子间相互作用的影响,从分子力学、分子动态学分析了人白介素6受体胞外区功能域关键氨基酸残基在受体与配基结合中的构象变化以及与人白介素6间的相互作用.     

肿瘤坏死因子与其受体相互作用的计算机模拟研究

利用同源模建方法,以肿瘤坏死因子(TNF)R55受体胞外区的晶体结构为参考模板,预测了TNFR75受体胞外区Cys18-Phe147片段的三维结构。根据R55受体胞外区与LT相结合的复合物的晶体结构,预测了TNF与R55及R75胞外区的复合物的三维结构,模拟了TNF与受体之间的相互作用。由于TNF与受体的作用形式是三聚体对三聚体,因此在模拟TNF与受体相互作用时选择了包括一个非对称的TNF三聚体和一个受体(R55或R75)单体的模拟系统。结合已有的突变体实验结果,利用计算机分析手段,发现了一些TNF突变体之所以具有受体选择性的三维结构基础和发挥了关键作用的氨基酸残基以及这些残基之间的主要作用形式。研究深化了对已有的突变体实验结果的认识,建立了不同的实验结果之间的内在关联,为以后有目的的新型突变体设计和实验研究打下了基础。     

老年慢性阻塞性肺疾病急性加重期患者血清CTRP-4、CTRP-6、CTRP-9与肺功能和炎症因子的相关性分析

摘要 目的：探讨老年慢性阻塞性肺疾病急性加重期（AECOPD）患者血清补体C1q/肿瘤坏死因子相关蛋白4（CTRP-4）、CTRP-6、CTRP-9与肺功能和炎症因子的相关性。方法：选取2020年1月～2022年1月我院收治的117例AECOPD患者为AECOPD组,72例慢性阻塞性肺疾病稳定期（SCOPD）患者为SCOPD组,另选取同期58例体检健康者为对照组。采用酶联免疫吸附法检测血清CTRP-4、CTRP-6、CTRP-9水平,通过Pearson/Spearman相关性分析老年AECOPD患者血清CTRP-4、CTRP-6、CTRP-9与肺功能指标[第1秒用力呼气容积占预计值百分比（FEV₁％）、第1秒用力呼气容积/用力肺活量（FEV₁/FVC）]和炎症因子[白细胞介素（IL）-1β、IL-6、IL-8、肿瘤坏死因子-α（TNF-α）]的相关性。结果：对照组、SCOPD组、AECOPD组血清CTRP-4水平依次升高,CTRP-6、CTRP-9水平依次降低（P＜0.05）。老年AECOPD患者血清CTRP-4水平与FEV₁％、FEV₁/FVC呈负相关,与血清IL-1β、IL-6、IL-8、TNF-α水平呈正相关（P＜0.05）;CTRP-6、CTRP-9水平与FEV₁％、FEV₁/FVC呈正相关,与血清IL-1β、IL-6、IL-8、TNF-α水平呈负相关（P＜0.05）。结论：血清CTRP-4水平升高和CTRP-6、CTRP-9水平降低与老年AECOPD患者肺功能降低和炎症反应有关,可能成为老年AECOPD防治的潜在靶点。     

中华绒螯蟹眼柄MTXO细胞GABA受体通道研究

采用全细胞膜片钳技术测定了中华绒螯蟹（Eriocheir sinensis）眼柄视神经节端髓X器官（MTXO）三种类型神经内分泌细胞对0.01～5mmol/L γ氨基丁酸（γ-aminobutyric acid,GABA）的反应,并结合选择性拮抗剂和激动剂的使用进行了GABA受体研究.在电流钳模式下,依据不同Nernst Cl^－电位,三种类型细胞均对GABA产生去极化或超级化反应.在电压钳模式下,GABA激活Cl^－通道电流（I_GABA）.I_GABA在灌流GABA后约1 200 ms内激活,800 ms内达到峰值,没有明显的脱敏反应,反转电位接近Nernst Cl^－电位.I_GABA幅值呈浓度依赖性,激活阈值为0.01 mmol/L,约在0.5 mmol/L达到饱和.药理学实验结果表明,中华绒螯蟹眼柄神经内分泌细胞GABA受体是Cl^－通道蛋白,对Cl^－离子通道阻断剂Picrotoxin和Niflumic acid敏感,但是对GABA_A受体拮抗剂Bicuculline和GABA_C受体激动剂cis-4-aminocrotonic acid (CACA)和trans-4-aminocrotonic (TACA)均不敏感.     

抗人IL-6单克隆抗体的制备及鉴定

用基因重组人IL-6免疫Balb/c小鼠,采用小鼠杂交瘤技术,筛选克隆到分泌抗人重组IL-6单克隆抗体的杂交瘤细胞株,并对其中2H₂、 1D₂ 和4B₄瘤细胞株进行了鉴定.其抗体类别均为IgG,亚类分别为IgG1和IgG2a.用多种细胞因子和无关蛋白的鉴别试验结果证实它们均特异地识别rhIL-6.免疫转染结果显示,该单抗识别分子质量为21 ku的IL-6单一条带.IL-6单克隆抗体的亲和常数K_aff= 1.62×10⁹ (mol/L)^-1.     

胰岛素及胰高血糖素对HepG2细胞载脂蛋白CⅢ受体功能的影响

为寻求一种可替代人肝细胞研究载脂蛋白（apolipoprotein, apo）CⅢ受体的生理模型,并探讨apoCⅢ受体的生理功能及其在内源性高甘油三酯血症发病机制中的作用,首先以¹²⁵I标记的人apoCⅢ为配体,利用放射性配体结合分析法观察了人肝癌细胞系HepG2细胞是否有apoCⅢ受体存在.结果证实HepG2细胞上存在高亲和力的、可饱和的、特异的apoCⅢ受体结合位点,其受体的亲和力(K_d)和apoCⅢ受体结合容量(B_max)分别为(9.53±1.03)×10^-9 mol/L和(3.28±0.31) μg/g.随后又分别研究了胰岛素及胰高血糖素对HepG2细胞apoCⅢ受体功能的影响,结果表明：胰岛素可使HepG2细胞apoCⅢ受体结合容量（B_max）显著增加,但对受体的亲和力（K_d）无影响;胰高血糖素可使HepG2细胞apoCⅢ受体亲和力显著下降（即K_d值升高）,对受体的结合容量无影响.提示人肝apoCⅢ受体的功能可能受胰岛素及胰高血糖素的不同调节.     

BiPAP正压无创呼吸机辅助治疗老年AECOPD的临床疗效及对患者肺功能、血清炎性因子和预后指标的影响

摘要 目的：观察双水平正压无创通气（bi-level positive airway pressure,BiPAP）辅助治疗老年慢性阻塞性肺疾病急性加重期（Acute Exacerbation of Chronic Obstructive Pulmonary Disease,AECOPD）的临床疗效以及患者治疗前后肺功能、血清炎性因子和预后指标的变化。方法：选择本院在2017年8月至2020年7月期间收治的150例AECOPD患者,采用随机数字表法分为对照组和研究组,每组75例。给予两组抗感染、祛痰、纠正水电解质紊乱、营养支持等基础治疗,在此基础上给予对照组患者低流量吸氧治疗,给予研究组患者选择合适面罩进行BiPAP治疗。比较两组治疗总有效率以及治疗前和治疗后肺功能指标[1 s用力呼气量（1 s forced expiratory volume,FEV₁）、FEV₁/用力肺活量（FEV₁/forced vital capacity,FEV₁/FVC）和FEV1占预计值百分比（FEV₁ as a percentage of predicted value,FEV₁%）]、血气指标[动脉血氧分压（Arterial partial pressure of oxygen,PaO₂）和动脉二氧化碳分压（arterial partial pressure of carbon dioxide,PaCO₂）]、血清炎性因子[白细胞介素-6（Interleukin-6,IL-6）、IL-8和肿瘤坏死因子α（TNF-α）水平]、可溶性髓样细胞触发受体-1（soluble triggering receptor expressed on myeloid cells-1,sTREM-1）以及全身性炎症反应综合征（systemic inflammatory response syndrome,SIRS）量化评分。结果：研究组和对照组患者治疗总有率分别为92.00 %和74.67 %（P<0.05）。两组治疗后FEV₁、FEV₁/FVC、FEV₁%、PaCO₂、SIRS评分以及血清IL-6、IL-8、TNF-α和sTREM-1水平都明显低于治疗前,PaO₂明显高于治疗前（P<0.05）。研究组治疗后FEV₁、FEV₁/FVC、FEV₁%、PaCO₂、SIRS评分以及血清IL-6、IL-8、TNF-α和sTREM-1水平都明显低于对照组,PaO₂明显高于对照组（P<0.05）。结论：BiPAP能够提高老年AECOPD患者临床疗效,改善肺功能、血气水平和预后,缓解炎症状态。     

hIL-6·hIL-6Rα·gp130三元复合物的结构预测

通过Delphi方法分析人白介素6（human interleukin-6,hIL-6）／人白介素6受体α亚基（human interleukin-6 receptor α subunit,hIL-6Rα）复合物、gp130（β subunit）的空间构象的表观静电分布,利用分子对接方法研究gp130与hIL-6/hIL-6Rα复合物作用形成三元复合物的空间构象,经过分子力学优化、分子动力学常温动态模拟借助分子间相互作用（范德华力、氢键、盐键等）、反应自由能理论探讨hIL-6·hIL-6Rα·gp130复合物稳定构象结合部位的结构域.分析结果表明,gp130蛋白表面富集较强的负电势,复合物hIL-6/hIL-6R一侧表面富集较强的正电势,gp130借助蛋白表面的静电作用结合hIL-6/hIL-6R复合物,介导hIL-6信号;hIL-6中的helix-C、loop-BC、loop-CD参与同gp130中的loopEF、linker、loopA′B′、loopB′C′、loopD′E′作用,hIL-6R中的loopA′B′、β-strand E′参与同gp130中的loopA′B′、β-strand E′作用.     

Characteristics of the membranes of the pellicle of the ciliatePseudomicrothorax dubius

Summary The membranes of the pellicle of the ciliatePseudomicrothorax dubius are investigated using thin section electron microscopy and freeze-fracture replicas. The plasma membrane is covered by a surface coat and is connected to the outer alveolar membrane by short, sometimes branched, bridges. The inner alveolar membrane is coated on both sides. The epiplasm lies in intimate contact with the cytoplasmic surface of this membrane, and there is a corresponding deposit on the other surface. This deposit is regularly striated.The epiplasmic layer and the alveoli are interrupted at sites of cytotic activity,e.g., the attachment sites of trichocysts, the cytoproct, and the parasomal sacs. The striated deposit ends where the epiplasm ends, indicating a direct relationship between these two epimembranous layers.There is a deposit along the sides of the first part of the tip of the trichocysts, and in this region the trichocyst membrane is free of intramembranous particles.The membrane of the parasomal sacs has a coat on both surfaces. That on the extraplasmic surface is similar to the surface coat of the plasma membrane. The origin of the cytoplasmic coat is unknown. The cytotic activity of these sacs is indicated by their highly irregular profiles.     

The early development of the tail and the transformation of the shape of the nucleus of the spermatid of the domestic fowl,Gallus gallus

Summary The differentiation of the spermatid, especially in reference to the formation of the flagellum, and transformation of the shape of the nucleus was investigated in the domestic fowl.In the early stage of the spermatid, a prominent Golgi apparatus appears around the centrioles. The Golgi vesicles then surround the axial-filament complex which develops from the distal centriole. These vesicles fuse to form continuous membrane at the earliest stage of flagellar formation, and in the succeeding stage Golgi lamellae are attached to the plasma membrane of the developing flagellum. From these observations, it is assumed that Golgi apparatus may be a source of the membrane system of the flagellum.The microtubules distributed around the nucleus form the circular manchette. The anterior region of the nucleus with the manchette is cylindrical in shape and the posterior region without it remains irregular in shape. When the circular manchette has been completed, the whole nucleus acquires a slender cylindrical shape. The circular manchette then changes into the longitudinal manchette. The nuclei of spermatids without a longitudinal manchette are abnormal in shape. In view of these observations it is assumed that the nuclear shaping of the spermatid may be accomplished by circular manchette and the maintenance of shape of the elongated nucleus by longitudinal manchette.The authors wish to thank Mr. Takayuki Mori for his helpful suggestions and technical advices     

Observations on the permeability of the choriocapillaris of the eye

Summary The choriocapillaris is a fenestrated capillary bed located posterior to the retinal pigment epithelium. It serves as the main source of supply to the photoreceptors, retinal pigment epithelium, and other cells of the outer retina. The permeability of these capillaries to intravenously injected ferritin (MW — approx. 480,000; mol. diam. 11 nm) was examined in the mouse, rabbit, and guinea pig, each of which is characterized by a different type of retinal vascularization. In all three species, the bulk of the ferritin remained in the capillary lumina, where it appeared to be blocked at the level of the diaphragmed fenestrae. Some ferritin was present in endothelial cell vacuoles. The results confirm previous work on the rat choriocapillaris and indicate that the barrier function of the choriocapillary endothelium is present even among species in which the retinal circulation differs significantly.Supported by NIH grant EY03418     

Separation of the pineal vesicle from the wall of the third ventricle during the post-hatching development of the chicken

Summary According to light- and electron-microscopic observations the pineal organ of the 3-day-old chicken consists of a prominent end vesicle and a tapering parenchymal stalk. During this stage the pineal lumen is in open communication with the third ventricle. However, in the 40-day-old chicken, which still possesses a well-developed end vesicle, the proximal portion of the pineal stalk displays regressive changes leading to local fragmentation. At this stage the pineal stalk is reduced, and the pineal lumen is missing. In 1-year-old chickens the parenchyma of the proximal portion of the stalk is further diminished, and in 3-year-old domestic fowl is completely displaced by bundles of collagenous fibers, only some nerve fibers being present. This post-hatching pineal development may reflect the sequence of changes leading from pineal sense organs to pineal glands.This work was supported by a grant-in-aid for Scientific Research from the Ministry of Education, Science and Culture of Japan