热疗联合顺铂对喉癌Hep-2细胞的影响研究

目的探讨热疗联合顺铂对喉癌Hep-2细胞的影响,了解热疗与顺铂的治疗方法是否有交互作用。方法将传代的Hep-2细胞分为对照组、热疗组、顺铂组及热疗联合顺铂组。对照组置于37℃培养箱,热疗组置于43℃培养箱,顺铂组置于37℃培养箱并加入顺铂,热疗联合顺铂组置于43℃培养箱并加入顺铂。采用MTT法、Wound-healing划痕实验和Transwell侵袭实验检测热疗联合顺铂对Hep-2细胞的增殖、迁移和侵袭力影响。结果4组细胞在波长490 nm处光密度(OD)值分别为(1.24±0.13)、(0.99±0.11)、(0.75±0.07)及(0.31±0.07),析因分析显示,不同温度热疗在波长490 nm处的OD值有差异(P<0.05),不同浓度顺铂在波长490 nm处的OD值有差异(P<0.05),热疗与顺铂对在波长490 nm处的OD值存在交互作用(P<0.05)。4组细胞未愈合区百分比分别为(31.83±1.62)%、(40.47±1.52)%、(53.13±2.61)%及(79.83±0.95)%,析因分析显示,不同温度热疗对未愈合区百分比有差异(P<0.05),不同浓度顺铂未愈合区百分比有差异(P<0.05),热疗与顺铂对未愈合区百分比的影响存在交互作用(P<0.05)。4组细胞穿过Transwell小室膜的细胞数目分别为(27.8±1.64)、(21.8±1.48)、(11.2±1.48)及(1.8±0.84)个,析因分析显示,不同温度热疗的穿膜细胞数有差异(P<0.05),不同浓度顺铂的穿膜细胞数有差异(P<0.05),热疗与顺铂对穿膜细胞数的影响存在交互作用(P<0.05)。结论热疗能够增强喉癌Hep-2细胞对顺铂的敏感性,热疗与顺铂联合有协同抗肿瘤作用。

考虑叶轮气动效应的离心压缩机转子稳定性分析

API 617标准中要求,离心压缩机产品(包括辅助设备)应确保其最短使用寿命为20年,不间断连续运转时间至少为5年。本文中的压缩机组高压缸转子在实际运行中发生了动力学失稳现象。通过分析,认为对于该机组的转子稳定性分析,应该考虑叶轮气动效应的影响,并发现考虑叶轮气动效应后的转子稳定性与实际运行情况一致,且不满足API 617的要求,为了改善该压缩机的转子稳定性,在叶轮口圈和平衡盘密封处添加阻旋栅,从分析结果看,该措施提高了转子的对数衰减率,满足API 617的要求。

Midkine accumulated in nucleolus of HepG2 cells involved in rRNA transcription

AIM: To invesgate the ultrastructural location of midkine (MK) in nucleolus and function corresponding to its location.METHODS: To investigate the ultrastructural location of MK in nucleolus with immunoelectronic microscopy.To study the role that MK plays in ribosomal biogenesis by real-time PCR.The effect of MK on anti-apoptotic activity of HepG2 cells was studied with FITC-conjugated annexin Ⅴ and propidium iodide PI double staining through FACS assay.RESULTS: MK mainly localized in the granular component (GC),dense fibrillar component (DFC) and the border between the DFC and fibrillar center (FC).The production of 45S precursor rRNA level was decreased significantly in the presence of MK antisense oligonucleotide in the HepG2 cells.Furthermore,it was found that exogenous MK could protect HepG2 from apoptosis significantly.CONCLUSION: MK was constitutively translocated to the nucleolus of HepG2 cells,where it accumulated and mostly distributed at DFC,GC components and at the region between FC and DFC,MK played an important role in rRNA transcription,ribosome biogenesis,and cell proliferation in HepG2 cells.MK might serve as a molecular target for therapeutic intervention of human carcinomas.

Impacts of exposure to 900 MHz mobile phone radiation on liver function in rats

Objective: To study the impacts of exposure to electromagnetic radiation(EMR) on liver function in rats. Methods: Twenty adult male Sprague-Dawley rats were randomly divided into normal group and radiated group. The rats in normal group were not radiated, those in radiated group were exposed to EMR 4 h/d for 18 consecutive days. Rats were sacrificed immediately after the end of the experiment. The serum levels of alanine aminotransferase(ALT) and aspartate aminotransferase(AST), and those of malondialdehyde(MDA) and glutathione(GSH) in liver tissue were evaluated by colorimetric method. The liver histopathological changes were observed by hematoxylin and eosin staining and the protein expression of bax and bcl-2 in liver tissue were detected by immunohistochemical method. Terminal-deoxynucleotidyl transferase mediated nick and labelling(TUNEL) method was used for analysis of apoptosis in liver. Results: Compared with the normal rats, the serum levels of ALT and AST in the radiated group had no obvious changes(P>0.05), while the contents of MDA increased(P<0.01) and those of GSH decreased(P<0.01) in liver tissues. The histopathology examination showed diffuse hepatocyte swelling and vacuolation, small pieces and focal necrosis. The immunohistochemical results displayed that the expression of the bax protein was higher and that of bcl-2 protein was lower in radiated group. The hepatocyte apoptosis rates in radiated group was higher than that in normal group(all P<0.01). Conclusion: The exposure to 900 MHz mobile phone 4 h/d for 18 days could induce the liver histological changes, which may be partly due to the apoptosis and oxidative stress induced in liver tissue by electromagnetic radiation.

Comparison of biliary protein spectrum in gallstone patients with obesity and those with normal body weight

Background:Obesity is a common public health issue and is currently deemed a disease.Research has shown that the risk of gallstones in individuals with obesity is elevated.This study aimed to explore the bile proteomics differences between cholelithiasis patients with obesity and normal body weight.Methods:Bile samples from 20 patients(10 with obesity and 10 with normal body weight)who underwent laparoscopic cholecystectomy at our center were subjected to tandem mass tag labeling(TMT)and liquid chromatography-tandem mass spectrometry(LC-MS/MS),followed by further bioinformatic analysis.Results:Among the differentially expressed proteins,23 were upregulated and 67 were downregulated.Bioinformatic analysis indicated that these differentially expressed proteins were mainly involved in cell development,inflammatory responses,glycerolipid metabolic processes,and protein activation cascades.In addition,the activity of the peroxisome proliferator-activated receptor(PPAR,a subfamily of nuclear receptors)signaling pathway was decreased in the Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis.Two downregulated proteins in the PPAR signaling pathway,APO A-I and APO A-II,were confirmed using enzyme-linked immunosorbent assay.Conclusions:The PPAR signaling pathway may play a crucial role in the development of cholelithiasis among patients with obesity.Furthermore,biliary proteomics profiling of gallstones patients with obesity is revealed,providing a reference for future research.

Upregulation of MiR-1280 Expression in Non-small Cell Lung Cancer Tissues

Background：Non-small cell lung cancer （NSCLC） is a prolific and high-mortality disease with few effective treatments.Although the detection and surgical techniques for NSCLC continue to advance,the survival rate for the patients with NSCLC remains poor.Enhanced predictive biomarkers such as microRNAs （miRNAs） are needed at the time of diagnosis to better tailor therapies for patients.This study focused on the expression ofmiR-1280 in NSCLC tissues and distal normal tissues in order to explore the association between miR-1280 expression and NSCLC.Methods：A total of 72 newly diagnosed primary NSCLC patients were enrolled in this study.Quantitative real-time polymerase chain reaction （PCR） was performed to identify the expression level ofmiR-1280 in the NSCLC tissues and distal normal tissues of these patients.Results：The miR-1280 expression was significantly higher in the NSCLC tissues （0.084 ± 0.099） than distal normal tissues （0.014 ± 0.015,P =0.009）.In 54 patients （75%）,the miR-1280 expression in the NSCLC tissues was upregulated （2-△△ct 〉 2）,and no case showed a downregulation of miR-1280 expression.Conclusions：The expression level ofmiR-1280 could be regarded as a biomarker for NSCLC.