Differentiation of the plasma membrane of hepatic cells in monolayer cultures

Hepatocytes from rats were isolated by treatment with trypsin and cultured. Plasma membranes at different culture stages were observed by electron microscopy. The activities of 5' nucleotidase and adenosinetriphosphatase on the plasma membranes were examined. The cell coat was also studied by use of the concanavalin A-peroxidase technique. The surfaces of single cells, covered with microvilli, are the site of adenosinetriphosphatase activity only and are devoid of 5'-nucleotidase activity. After a few h of culture, the cells are grouped together in tight clusters or long trails and are separated by an intercellular space of 250 A, partially permeable to lanthanum nitrate. The juxtaposed plasma membranes on which 5'-nucleotidase and adenosinetriphosphatase activities occur also delimit spaces similar to bile canaliculi. The formation of junction complexes and their permeability to lanthanum nitrate was also studied. No enzymatic activity is observed at the junctions. The numerous tight junctions, impervious to the tracer, are always accompanied by a profusion of microfilaments. Mature desmosomes are rare, and are present only in the form of "maculae adhaerentes diminutae." The gap junctions, nearly always permeable to the tracer, form rapidly and assume a variety of shapes (trail, bulge and ring-like), the significance of which is open to discussion. The use of concanavalin A permits localization of the free sugar sites on the surface of the cells, in the pinocytotic vesicles and in the internal space of the gap junctions.     

Putative therapeutic impacts of cardiac CTRP9 in ischaemia/reperfusion injury

Recently, cytokines belonging to C1q/tumour necrosis factor‐related proteins (CTRPs) superfamily have attracted increasing attention due to multiple metabolic functions and desirable anti‐inflammatory effects. These various molecular effectors exhibit key roles upon the onset of cardiovascular diseases, making them novel adipo/cardiokines. This review article aimed to highlight recent findings correlated with therapeutic effects and additional mechanisms specific to the CTRP9, particularly in cardiac ischaemia/reperfusion injury (IRI). Besides, the network of the CTPR9 signalling pathway and its possible relationship with IRI were discussed. Together, the discovery of all involved underlying mechanisms could shed light to alleviate the pathological sequelae after the occurrence of IRI.     

Gene expression profile in immunologically injured liver cell of mice

To study the gene expression profiles between immunologically injured liver cell and normal liver cell of mice and to screen on a large scale the differentially expressed genes associated with the formation of liver injury, the experimental mice were randomly divided into the normal group for controlling and the immunologically liver-injured group induced by BCG and LPS. The liver mRNA of the two groups were extracted respectively and reversely-transcribed to cDNA with the incorporation of different fluorescence (Cy3, Cy5) labeled dUTP as the hybridization probes. The mixed probes were hybridized to the cDNA microarray chips. The fluorescent signal results were acquired by scanner ScanArray 4000 and analyzed with software GenePix Pro 3.0. Among the 14112 target genes, 293 genes were found to be significantly differentially expressed, in which 188 genes were up-regulated and 105 genes were down-regulated. Based on the analysis of biological functions of those differentially expressed genes, it was indicated that the occurrence and development of mouse liver damage induced by BCG and LPS were highly correlated with the processes of immune reactions, cell synthesis, metabolism, apoptosis and transportation in liver cell, which might be quite important for elucidating the regulatory network of gene expression associated with the liver damage, also important for finally discovering the pathogenic mechanisms of immunological liver damage.     

The effect of jasmonic acid on the accumulation of ABA,proline and spermidine and its influence on membrane injury under water deficit in two barley genotypes

Seedlings of two barley genotypes (‘Maresi’ and wild form of Hordeum spontaneum) were treated with jasmonic acid (JA 5 μM and 15 μM) for 24 h, and then subjected to water stress (PEG 6000 solution of − 1.5 MPa). JA caused an increase in the content of ABA but not in that of proline and spermidine in the two studied genotypes. The effect of the treatment did not depend on the applied JA concentration. The pre-stress treatment with JA changed plant response to water deficit with regard to membrane injury. Treatment with a lower JA concentration (5 μM) caused a substantial reduction of the stress-induced membrane damage in the both genotypes. A higher JA concentration (15 μM) caused the reduction of membrane injury only in H. spontaneum and was ineffective in ‘Maresi’. JA had no influence on the leaf water status in water-stressed plants. A possible role of JA in leaf ABA accumulation and alleviation of cell membrane injury under water deficit is discussed. The work was partly supported by the Polish Committee For Scientific Research, grant No 5 PO6A 036 18     

小鼠胎肝细胞透明质酸3D培养体系的建立

目的 利用透明质酸建立小鼠胎肝细胞3D培养体系。 方法 分离获得胚胎12-14天胎肝细胞,利用KM培养基进行初步2D肝干/祖细胞的筛选培养,并利用透明质酸及KM培养基配制水凝胶建立3D细胞培养体系。 结果 胎肝细胞在2D体系中呈现克隆状生长。分离培养获得的肝干/祖细胞克隆在透明质酸建立的3D培养体系保持增殖活性,并进一步获得肝细胞功能特性,表现为3D培养上清中白蛋白合成和尿素水平显著增加。Q-PCR结果显示随着3D培养时间的延长,其肝细胞干性标志如AFP、CK19、EpCAM、Prox1等表达水平都大幅度降低且接近成年小鼠肝脏表达水平。 结论 本研究成功建立基于透明质酸的小鼠胎肝细胞的3D无血清培养体系,并可促进小鼠胎肝细胞肝细胞功能进一步成熟。     

CHANGES IN PHOTOSYNTHESIS IN RESPONSE TO COMBINED IRRADIANCE AND TEMPERATURE STRESS IN CYANOBACTERIAL SURFACE WATERBLOOMS1

Buoyant cyanobacteria, previously mixed throughout the water column, float to the lake surface and form a surface waterbloom when mixing subsides. At the surface, the cells are exposed to full sunlight, and this abrupt change in photon irradiance may induce photoinhibition; at the same time, temperature rises as well. This study investigated the damaging effects of this increase in temperature as well as the ecologically more relevant combination of both an increased temperature and a high photon irradiance. Analysis of surface blooms with oxygen microelectrodes showed that integrated oxygen contents that are dependent on the balance of photosynthetic oxygen evolution and respiratory oxygen uptake decreased when temperature was raised above the lake temperature. Gross rates of photosynthesis were unaffected by temperatures up to of 35°C; hence, a moderate increase in temperature mainly stimulated oxygen uptake. Preincubation of cells of the cyanobacterium Anabaena flos-aquae (Lyngb.) de Brébisson at temperatures up to 35°C did not affect the subsequent measurement of rates of net photosynthesis. Another 5°C rise in temperature severely damaged the photosynthetic apparatus. Failure to restore net rates of photosynthesis was coupled to a strong quenching of the ratio of variable to maximum fluorescence, F_v/F_m, that was the result of a rise in F_o. A combination of high temperature and high photon irradiance was more damaging than high temperature alone. In contrast, low photon irradiances offered substantial protection against heat injury of the photosynthetic apparatus. I conclude from this study that because cyanobacteria usually are acclimated to low average irradiance prior to bloom formation, there is a reasonable risk of chronic photoinhibition. The increase in temperature will enhance the photodamage of cells in the top layer of the bloom. Low photon irradiances in subsurface layers will offer protection against heat injury. If the high temperatures extend to the deepest, dark layers of the bloom, damage in those layers is likely to occur.     

原发性肝癌患者术后癌因性疲乏的影响因素及其预测模型构建

摘要 目的：分析原发性肝癌患者术后癌因性疲乏（CRF）的影响因素并构建预测模型。方法：选取2020年1月～2023年1月湖南师范大学附属第一医院收治接受手术治疗的200例原发性肝癌患者,根据术后3个月是否存在CRF将患者分为CRF组（124例）和非CRF组（76例）。单因素和多因素Logistic回归分析影响原发性肝癌患者术后CRF的因素并构建其预测模型。通过受试者工作特征（ROC）曲线分析预测模型对原发性肝癌患者术后CRF的预测价值。结果：单因素分析显示,CRF组病程长于非CRF组,Child-Pugh分级B级、美国东部肿瘤协作组功能状态（ECOG）评分1～2分、辅助化疗、医疗付费方式自费、抑郁/焦虑比例高于非CRF组,文化程度高中及以上、家庭月收入＞3000元、高度社会支持度比例低于非CRF组（P＜0.05）。多因素Logistic回归分析显示,病程延长、Child-Pugh分级B级、ECOG评分1～2分、辅助化疗、医疗付费方式自费、抑郁/焦虑为影响原发性肝癌患者术后CRF的独立危险因素,家庭月收入＞3000元、高度社会支持为独立保护因素（P＜0.05）。原发性肝癌患者术后CRF的预测模型方程：Logit（P）=P/1-P=-1.252+0.409×病程+0.839×Child-Pugh分级+1.378×ECOG评分+1.055×辅助化疗+1.476×医疗付费方式-0.793×家庭月收入+0.883×抑郁/焦虑-1.260×社会支持度。霍斯默-莱梅肖检验P＞0.05。ROC曲线分析显示,模型预测原发性肝癌患者术后CRF的曲线下面积为0.910,敏感度为87.10%,特异度为85.53%。结论：病程、Child-Pugh分级、ECOG评分、辅助化疗、医疗付费方式、抑郁/焦虑、家庭月收入、社会支持度为影响原发性肝癌患者术后CRF的因素,基于此构建的预测模型对原发性肝癌患者术后CRF的预测价值较高,可能有助于临床早期发现和干预原发性肝癌患者术后CRF,以改善患者预后。     

呼气末二氧化碳分压、C-反应蛋白/白蛋白比值及综合脱机指数对重型颅脑损伤机械通气患者撤机失败的预测价值

摘要 目的：探讨呼气末二氧化碳分压（PetCO₂）、C-反应蛋白/白蛋白比值（CRP/Alb）及综合脱机指数（IWI）对重型颅脑损伤机械通气患者撤机失败的预测价值。方法：选择2020年1月至2022年6月在安徽中医药大学附属六安医院进行机械通气的重型颅脑损伤患者96例作为研究对象,按照撤机结局分为撤机失败组（n=31）和撤机成功组（n=65）。比较两组撤机前PetCO₂、CRP/Alb、IWI及临床参数。应用多因素Logistic回归分析重型颅脑损伤机械通气患者撤机失败的危险因素。应用受试者工作特征（ROC）曲线评价PetCO₂、CRP/Alb、IWI对重型颅脑损伤机械通气患者撤机失败的预测价值。结果：撤机失败组PetCO₂、CRP/Alb、急性生理功能和慢性健康状况评分系统II（APACHE II）评分显著高于撤机成功组,机械通气时间长于撤机成功组,IWI、格拉斯哥昏迷评分（GCS）显著低于撤机成功组（P<0.05）。多因素Logistic回归分析显示,PetCO₂≥37.01 mmHg、CRP/Alb≥0.97、IWI≤78.23、GCS≤5.90分、APACHE II评分≥26.17分、机械通气时间≥4.49 d是重型颅脑损伤机械通气患者撤机失败的危险因素（P<0.05）。ROC曲线分析结果显示PetCO₂、CRP/Alb、IWI、GCS、APACHE II对重型颅脑损伤机械通气患者撤机失败均有较高的敏感度、特异度, PetCO₂、CRP/Alb、IWI三项联合检测对重型颅脑损伤机械通气患者撤机失败预测的曲线下面积（AUC）高于PetCO₂、CRP/Alb、IWI、GCS、APACHE II单独检测。结论：PetCO₂、CRP/Alb及IWI联合评估对重型颅脑损伤机械通气患者撤机失败具有较高的预测价值。