Simulated Microgravity Inhibits the Proliferation of Chang Liver Cells by Attenuation of the Major Cell Cycle Regulators and Cytoskeletal Proteins

Simulated microgravity (SMG) induced the changes in cell proliferation and cytoskeleton organization, which plays an important factor in various cellular processes. The inhibition in cell cycle progression has been considered to be one of the main causes of proliferation inhibition in cells under SMG, but their mechanisms are still not fully understood. This study aimed to evaluate the effects of SMG on the proliferative ability and cytoskeleton changes of Chang Liver Cells (CCL-13). CCL-13 cells were induced SMG by 3D clinostat for 72 h, while the control group were treated in normal gravity at the same time. The results showed that SMG reduced CCL-13 cell proliferation by an increase in the number of CCL-13 cells in G0/G1 phase. This cell cycle phase arrest of CCL-13 cells was due to a downregulation of cell cycle-related proteins, such as cyclin A1 and A2, cyclin D1, and cyclin-dependent kinase 6 (Cdk6). SMG-exposed CCL-13 cells also exhibited a downregulation of α-tubulin 3 and β-actin which induced the cytoskeleton reorganization. These results suggested that the inhibited proliferation of SMG-exposed CCL-13 cells could be associate with the attenuation of major cell cycle regulators and main cytoskeletal proteins.     

医学肝脏图像Gabor小波纹理特征研究

针对肝脏图像自身特点,研究了Gabor小波纹理特征在医学肝脏图像识别中的意义,提出一种基于Gabor小波纹理特征的医学肝脏图像识别方法.实验表明:引进Gabor小波纹理特征能较好地实现医学肝脏图像识别问题;与其它典型图像识别方法对比结果验证,新方法可以取得更高的识别率.     

Stacked Gated Recurrent Unit Classifier with CT Images for Liver Cancer Classification

Liver cancer is one of the major diseases with increased mortality in recent years, across the globe. Manual detection of liver cancer is a tedious and laborious task due to which Computer Aided Diagnosis (CAD) models have been developed to detect the presence of liver cancer accurately and classify its stages. Besides, liver cancer segmentation outcome, using medical images, is employed in the assessment of tumor volume, further treatment plans, and response monitoring. Hence, there is a need exists to develop automated tools for liver cancer detection in a precise manner. With this motivation, the current study introduces an Intelligent Artificial Intelligence with Equilibrium Optimizer based Liver cancer Classification (IAIEO-LCC) model. The proposed IAIEO-LCC technique initially performs Median Filtering (MF)-based pre-processing and data augmentation process. Besides, Kapur’s entropy-based segmentation technique is used to identify the affected regions in liver. Moreover, VGG-19 based feature extractor and Equilibrium Optimizer (EO)-based hyperparameter tuning processes are also involved to derive the feature vectors. At last, Stacked Gated Recurrent Unit (SGRU) classifier is exploited to detect and classify the liver cancer effectively. In order to demonstrate the superiority of the proposed IAIEO-LCC technique in terms of performance, a wide range of simulations was conducted and the results were inspected under different measures. The comparison study results infer that the proposed IAIEO-LCC technique achieved an improved accuracy of 98.52%.     

Estimated exposure to hepatitis E virus through consumption of swine liver and liver sausages

A quantitative risk assessment was undertaken following the Codex Alimentarius principles in order to predict the exposure of consumers to hepatitis E virus (HEV) through food consumption. Taking into account the tropism of HEV, fresh liver and liver sausages were regarded as having a higher risk of contamination. The model entailed a hypothetical food pathway and was based on worst case scenario where the intake of contaminated food derived from a 100% HEV-infected pig population was estimated. As no data on the prevalence of infectious HEV was available, the HEV-RNA prevalence in food matrices and the seroprevalence of HEV-specific antibodies in swine were assessed and adjusted for diagnostic misclassification and sampling uncertainty. Considering a HEV prevalence of 100% in pigs and excluding further cross-contamination events, a food portion consisting of 130 gr of liver or of 32.5 gr of sausage (containing 30% of liver) yielded an estimated exposure of 8047 and 210 RNA copies (median values), respectively. These findings take into account the effect of thermal treatment on the HEV-RNA concentration of food. Due to the lack of information concerning the correlation between HEV-RNA concentration and the amount of infectious virus as well as the dose-response relationship of HEV, the calculated RNA copies do not allow direct conclusions to be drawn on the risk of infection following ingestion of these food types. The true prevalence was estimated for Switzerland and Germany, leading to an overall prevalence of HEV-RNA in food of 6.2% (90% Highest Density Intervals (HDIs): 2.5%–11.2%). In comparison with fresh liver, liver sausages showed a higher prevalence, most likely due to the presence of more than one liver within the same sausage. The true prevalence of anti-HEV IgG ranged between 59.4% (HDIs 56.5%–62.4%) and 62.6% (HDIs 58.8%–64.3%) and between 7.6% (HDIs 3.3%–13.2%) and 30.5% (HDIs 23.2%–38.2%) in pigs and wild boars, respectively. The high prevalence of antibodies support the evidence that these animals can act as reservoirs for HEV and can contribute epidemiologically to the maintenance of the virus in the surroundings. This study is a preliminary investigation and highlights the major existing gaps needed to be filled in order to enable a refined HEV risk assessment that can drive future decisions for the implementation of food safety and of control measures.     

四氯化碳复合、梯段用药法制备大鼠门脉高压模型的研究

目的探讨构建一种稳定、可靠的门脉高压大鼠模型的制备方法,并研究该模型肝脏病理结构以及血流动力学的改变。方法雄性SD大鼠95只,体重150～170g,按编号法随机分为模型组和对照组。模型组:按0.4mL/100g剂量予以背部皮下注射50%CCl4橄榄油溶液,每周2次,持续4周。第5周开始改为以0.5mL/100g标准注射,每周2次,持续4周。对照组:仅注射橄榄油,频度及剂量同模型组。结果对照组10只大鼠全部存活。模型组85只大鼠,死亡24只,死亡率28%。存活61只大鼠,肝脏均可观察到纤维组织不同程度地增生,肝小叶结构破坏,假小叶形成,模型成功率100%。模型组门静脉压力和门静脉内径比对照组明显增加(P<0.05);血清TB、ALT及AST较正常对照组均明显升高(P<0.05),而ALB则明显降低(P<0.05)。结论该方法所构建的动物模型其组织学改变与人类肝硬变相似,门静脉压力显著增高,是研究门脉高压症的理想模型。