Introduction Previous studies have demonstrated that the expression of cytochrome c oxidase (COX) subunits encoded by mitochondrial DNA is elevated in colorectal cancer (CRC). However, the expression of nuclear DNA-encoded COX IV and its clinical significance have not yet been investigated in CRC. Material and methods We examined COX IV expression in paired CRC samples (cancer and pericancerous tissues) by quantitative real-time polymerase chain reaction (qPCR), Western blot and immunohistochemical staining and analyzed its clinical significance. Results qPCR and Western blot analyses showed that COX IV expression was significantly elevated at both the mRNA (p = 0.05) and protein levels in CRC tissue samples when compared with those in paired pericancerous tissues. Immunohistochemistry also revealed that COX IV expression was significantly increased in CRC tissues (p < 0.001). Association analyses showed that there was no significant association between COX IV expression and clinical parameters of CRC patients except for gender (p = 0.017). Moreover, we did not find any association between COX IV expression and overall survival or recurrence-free survival of CRC patients. Further analysis showed no significant relationship between the expression of COX IV and proliferating cell nuclear antigen (PCNA), a marker of cell proliferation. Conclusions Our findings suggest that elevated COX IV expression may play an important role in colorectal carcinogenesis, but not in progression, which warrants further investigation in future studies.

Epidemiological studies have demonstrated that leukocyte telomere length is associated with the developing risk of various malignancies, including glioma. However, its prognostic value in glioma patients has never been investigated.

BACKGROUND AND AIM:It was commonly accepted that chemotherapeutic cytotoxicity was the main cause for hepatic failure in hepatocellular carcinoma patients after repeated transarterial chemoembolization (TACE). However, the effect of embolization-induced hypoxia on liver cirrhosis has rarely been concerned. METHODS:Serum levels of alanine aminotransferase, aspartate aminotransferase, and albumin were used to detect liver injury. Hepatic artery ligation was performed in carbon tetrachloride-induced rat hepatic fibrosis model to mimic the effect of hepatic hypoxia on liver fibrosis after TACE. Sirius Red staining and immunohistochemical analysis of alpha-smooth muscle actin (α-SMA) were used to detect the activation of hepatic stellate cells. Moreover, the expression of hypoxia and fibrosis-related molecules were analyzed at protein and/or mRNA level. RESULTS:Patients showed a significant increase in alanine aminotransferase and aspartate aminotransferase (P = 0.006), accompanied by a decrease in albumin (P = 0.005) after repeated TACE. Hepatic artery ligation significantly promoted carbon tetrachloride-induced rat liver fibrosis progression as indicated by Sirius Red and α-SMA staining, as well as increased expression of hypoxia-inducible factor (HIF)-1α, transforming growth factor (TGF)-β1, and vascular endothelial growth factor (VEGF). Conditioned media of hypoxia-treated L02 cells induced the expression of Collagen I and α-SMA in LX-2 cells, which was inhibited by HIF-1α small interfering RNA. Finally, HIF-1α inhibitor LW6 attenuated the hypoxia-induced fibrosis progression in vivo. CONCLUSION:Our data demonstrate that TACE-induced hepatic hypoxia aggravates the fibrosis progression in peritumoral liver tissue, thus leads to the deterioration of liver function. Intervention of HIF-1α might be a valuable strategy to optimize the efficacy and reduce the complication of TACE.

Over-expression of de novo lipogenesis (DNL) pathway genes is associated with the prognosis of various types of cancers. However, effects of single nucleotide polymorphisms (SNPs) in these genes on recurrence and death of hepatocellular carcinoma (HCC) patients after surgery are still unknown. A total of 492 primary HCC patients treated with surgery were included in this study. Nine SNPs in 3 genes (ACACA, FASN and ACLY) of DNL pathway were genotyped. Multivariate Cox proportional hazard regression model and Kaplan-Meier curve were used to analyze the association of SNPs with clinical outcomes. Two SNPs in ACACA gene were significantly associated with overall survival of HCC patients. Patients carrying homozygous variant genotype (VV) in rs7211875 had significantly increased risk of death, while patients carrying VV genotype in rs11871275 had significant decreased risk of death, when compared with those carrying homozygous wild-type or heterozygous genotypes. Moreover, patients carrying VV genotype in rs11871275 had decreased recurrence risk, while patients carrying variant genotype in rs4485435 of FASN gene had increased recurrence risk. Further cumulative effect analysis showed significant dose-dependent effects of unfavorable SNPs on both death and recurrence. SNPs in DNL genes may serve as independent prognostic markers for HCC patients after surgery.

Although previous evidence indicates close involvement of CD147 in the pathogenesis of liver fibrosis, the underlying molecular mechanisms and its therapeutic value remain largely unknown. In the present study, we investigated the biological roles of CD147 in liver fibrosis and assessed its therapeutic value as a target molecule in the CCl4-induced liver fibrosis mouse model. We found that CD147 was highly expressed in both hepatocytes and SECs (sinusoidal endothelial cells) in fibrotic liver tissues. Additionally, it was significantly associated with the fibrosis stage. TGF-β1 (transforming growth factor β1) was found to be mainly responsible for the up-regulation of CD147. Bioinformatic and experimental data suggest a functional link between CD147 expression and VEGF-A (vascular endothelial growth factor A)/VEGR-2 (VEGF receptor 2) signalling-mediated angiogenesis in fibrotic liver tissues. Furthermore, we observed that the CD147-induced activation of the PI3K (phosphoinositide 3-kinase)/Akt signalling pathway promotes the production of VEGF-A in hepatocytes and expression of VEGFR-2 in SECs, which was found to enhance the angiogenic capability of SECs. Finally, our data indicate that blocking of CD147 using an mAb (monoclonal antibody) attenuated liver fibrosis progression via inhibition of VEGF-A/VEGFR-2 signalling and subsequent amelioration of microvascular abnormality in the CCl4-induced mouse model. Our findings suggest a novel functional mechanism that CD147 may promote liver fibrosis progression via inducing the VEGF-A/VEGFR-2 signalling pathway-mediated cross-talk between hepatocytes and SECs. New strategies based on the intervention of CD147 can be expected for prevention of liver fibrosis.

Objective To assess the association between polymorphisms in HIF1α gene and prognosis of advanced hepatocelluar carcinoma.Methods We collected prognosis data from a cohort of 448 advanced HCC patients treated by transarterial chemoembo-lisation,and used 5ml peripheral blood from patients for extraction DNA.Three SNPs (rs2301 1 13、rs2057482 and rs1 957757 )in HIF1αgene were selected and genotyped.Multivariate Cox proportional hazards model,Kaplan-Meier curve and log-rank test were used for prognosis analyses.Results The variant-containing genotypes (WV+VV)of SNP rs2301 1 13 exhibited a significant associ-ation with a better overall survival in HCC patients who had tumor size smaller than 5 cm (hazard ratio [HR],0.58,95% confidence interval [CI],0.35-0.96,P =0.036).In the patients taken single tumor subgroup,the variant-containing genotypes (WV+VV) of SNP rs2301 1 13 exhibited a significant association with a better overall survival (log-rank P =0.048),comparing to those carrying wild-type genotype.Conclusion Our results suggest that polymorphisms in HIF1αgene may serve as an independent prognosis bio-marker for advanced HCC patient.

CD112 as an important ligand of CD226 can stimulate the natural killer (NK) cell-mediated target cell lysis. Previous studies have reported that CD112 is involved in cancer initiation and progression. However, its expression and clinical significance in hepatocellular carcinoma (HCC) have never been investigated. In this study, we used immunohistochemistry to examine CD112 expression in cancer and pericancer tissues from 159 HCC cases. Western blot and immunofluorescence were used to detect CD112 expression in HCC cell lines. χ(2) Test was used to assess the association of CD112 expression with clinicopathological characteristics, whereas Kaplan-Meier survival function and Cox proportional hazards regression model were used to explore the association between CD112 expression and clinical outcome of patients with HCC. Overall, CD112 expression was significantly reduced in HCC tissues when compared with adjacent pericancer liver tissues (P < .001). Western blot and immunofluorescence analyses showed that most HCC cell lines had low CD112 expression level. Furthermore, low CD112 expression was significantly associated with high serum α-fetoprotein level (P = .004) in patients with HCC. Kaplan-Meier analysis showed that patients with low CD112 expression had poorer postsurgery overall survival than those with high CD112 expression (log-rank P = .045). In conclusion, our findings demonstrate that the down-regulation of CD112 may be an important mechanism through which HCC cells evade the natural killer cell-mediated immunosurveillance, and thus, CD112 may be a useful biomarker to assess the immunologic niche of HCC.

针对我国医学研究生培养过程中出现的学生创新观念淡薄、平台建设不足、培养目标单一、培养模式封闭等问题,提出了一种以提升创新能力为核心,建设开放的资源共享平台,建立基础与临床长期稳定的开放性、协作式发展的研究生培养合作机制,提高了研究生创新能力,促进了医学教育的发展.

Metabolic reprogramming is a hallmark of cancer, including the alterations of activity and expression in tricarboxylic acid (TCA) cycle key enzymes. However, the significance of single nucleotide polymorphisms (SNPs) in genes encoding these key enzymes has not been investigated in hepatocellular carcinoma (HCC).

AimsCD155 is an important ligand in triggering tumour rejection by immune cells. However, the expression of CD155 and its clinical significance in hepatocellular carcinoma (HCC) remains unknown.Methods and resultsWe examined the expression level of CD155 in 174 HCC tissue samples by immunohistochemical staining and in HCC cell lines by flow cytometry; 63.8% (111 of 174) of HCC tissue samples showed negative CD155 expression. When compared with adjacent peritumour tissues, HCC tissues exhibited a significantly lower expression of CD155 (P < 0.001). Flow cytometry analysis indicated that HCC cell lines had low levels of CD155 expression. Moreover, negative CD155 expression was associated significantly with higher serum α‐fetoprotein level (P = 0.016) and a higher incidence of portal vein tumour thrombus (P = 0.050). Importantly, patients with positive CD155 expression had better overall survival after surgery than those with negative CD155 expression (P = 0.005). Furthermore, Cox regression analyses showed that CD155 expression was an independent prognostic factor for HCC (P = 0.049).ConclusionsOur findings suggest that loss of CD155 expression may play an important role in the immune escape of HCC cells and thus CD155 may serve as a prognostic marker as well as a potential therapeutic target for HCC.

Background: It was previously reported that propofol, an intravenously administered hypnotic and anesthetic agent, protects organs from ischemia-reperfusion (I/R) injury. However, the underlying mechanisms are largely unknown. Glycogen synthase kinase 3 beta (GSK-3 beta) is known to play an important role in the oxidative stress-induced apoptosis. In this study, we investigated the role of GSK-3 beta and mitochondrial permeability transition pore (MPTP) in the protective effects of propofol against hepatic I/R injury.Materials and methods: The left and median hepatic artery and the portal vein branches were blocked by no-damage artery clips to create the model of partial ischemia (70%), and liver lobes were subjected to warm ischemia for 30, 60, 90 min, respectively. Reperfusion of 120 min was then initiated by the removal of clamp. The MPTP opening was assessed by measuring mitochondrial large amplitude swelling and mitochondrial membrane potential.Results: Pretreatment with propofol in conditions of hepatic I/R inhibits the apoptosis of hepatocytes as evidenced by decreased terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells. Importantly, propofol suppressed the mitochondrial GSK-3 beta by promoting or preserving its phosphorylation at Ser9, thus restraining the opening of MPTP and preventing the mitochondrial swell and mitochondrial membrane potential collapse.Conclusions: Propofol protects liver from I/R injury by sustaining the mitochondrial function, which is possibly involved with the modulation of MPTP and GSK-3 beta. (C) 2013 Elsevier Inc. All rights reserved.

GW9508 is an agonist of G protein-coupled receptor 40 (GPR40) that is expressed in pancreatic β-cells and is reported to regulate insulin secretion. However, the effects of GW9508 on pancreatic β-cells in primary culture have not been well investigated. This study measured the acute effects of GW9508 on insulin secretion from rat pancreatic islets in primary culture, and the insulin secretion-related events such as the changes in membrane potential, ATP-sensitive potassium currents (KATP currents), and intracellular Ca(2+) concentrations ([Ca(2+)]i) of rat islet β-cells were also recorded. GW9508 (10-40 μM) did not influence basal insulin levels at 2 mM glucose, but it (above 20 μM) significantly inhibited 5 and 15 mM glucose-stimulated insulin secretion (GSIS). GW9508 did not inhibit insulin secretion stimulated by tolbutamide, the closer of KATP channels. GW9508 activated KATP channels and blocked the membrane depolarization and the increase in [Ca(2+)]i that were stimulated by glucose. GW9508 itself stimulated a transient increase in [Ca(2+)]i, which was fully blocked by depletion of intracellular Ca(2+) stores with thapsigargin or by inhibition of phospholipase C (PLC) activity with U73122. GW9508-induced activation of KATP channels was only partly inhibited by U73122 treatment. In conclusion, although it stimulates a transient release of Ca(2+) from intracellular Ca(2+) stores via activation of PLC, GW9508 inhibits GSIS by activating KATP channels probably in a distal step to GPR40 activation in rat β-cells.

医学微生物学实验课程是一门实践性、应用性极强的学科,而实验教学又是医学微生物教学的重要环节之一,也是培养学员掌握医学微生物实验基本技术和实验技能的有效手段.通过整合与优化实验教学内容,充分进行实验准备,精心组织与安排实验,及时总结与归纳,建立有效的实验考核模式等方法,以提高实验教学质量.

围绕如何在微生物实验技术教学中培养学员的创新能力,对课程内容、教学方法以及考核方式进行了改革和探索,构建了适合于生物技术专业本科生创新能力的实验教学体系.

细胞培养技术是医学和生物学研究中普遍应用的手段,在医学科研和临床应用领域里占据着极其重要的地位,也是研究型学生应该掌握的一门基本理论和技术。研究生在细胞培养实验课中学习到的理论和技术,很快就会应用到今后的科研工作中。结合实验教学的实施过程,浅谈研究生细胞培养技术课程实验教学准备实践中的几点体会。

Objectives Insulin has been shown to possess cardioprotective effect in acute myocardial ischaemia/reperfusion (MI/R). The present study attempted to test whether long term insulin treatment influences adverse prolonged post-ischaemic cardiac structural and functional changes and to further investigate the underlying mechanisms. Methods Adult male rats were subjected to left anterior descending coronary artery occlusion and were randomised to receive one of the following treatments: saline (4 ml/kg/h i.v. injection beginning 10 min before the ischaemia and continuing for 2 h), insulin (60 U/l, i.v. injection following the same routine, and hypodermic injection of insulin (0.5 U/ml, 1 ml/kg/d) for 4 weeks after the ischaemia surgery), insulin plus a PI3K/Akt inhibitor wortmannin (15 mg/kg i.v. injection 15 min before each insulin administration), or insulin plus a p38 MAPK inhibitor SB239063 (0.5 mg/kg following the same routine). Results At the end of 4 weeks after the ischaemia surgery, MI rats receiving long term insulin treatment showed smaller systolic left ventricle cavity (LVs) and thicker systolic interventricular septum (IVS), and increased cardiac ejection fraction (EF), left ventricular development pressure (LVDevP) and the instantaneous first derivation of left ventricle pressure (±LV dP/dtmax) (all p<0.05 vs saline). Moreover, the insulin treatment significantly increased Akt but inhibited p38 MAPK phosphorylations, and increased the plasma brain natriuretic peptide (BNP) level though it did not change the BNP mRNA expression. These cardioprotective effects of insulin and its effect on BNP were not blocked by the PI3K/Akt inhibitor wortmannin, and could not be further strengthened by the p38 MAPK inhibitor SB239063 (all p<0.05). Conclusions These data indicate that insulin improves post-ischaemic cardiac structural and functional changes via inhibiting p38 MAPK activation and thus increasing plasma BNP level.

In this paper,in order to cultivate students＇ autonomous learning ability,reform of self-study course had been made on the introduction of basic medicine,and good effect had been got.In the teaching reform,the following efforts have been made:sublimating both teachers and students＇educational ideas to adopt student-centered teaching model,and creating a positive self-study environment for students by improving teachers＇ instructions and teaching students learning strategies,and reforming the course assessment system to examine and evaluate student' s performances in the whole process of the course study so as to improve learning efficiency.

Objectives Patients with type 2 diabetes mellitus (DM), which is characterised by hyperlipidaemia, are liable to more severe and fatal myocardial infarction. Semen Cassiae is proved to reduce serum unsaturated fatty acids levels. This study was to investigate whether the Semen Cassiae extract reduces myocardial ischaemia and reperfusion (MI/R) injury, and if so, to further study the underlying mechanisms. Methods The high-fat diet-fed streptozotocin (HFD-STZ) rat model (type 2 DM model) was developed. Age- and gender-matched normal and DM rats were given the extract mixed into the fodder of the concentration of 50 g crude herbal medicine/kg BW for 14 days. Subsequently these animals were subjected to 30 min of myocardial ischaemia and 4 h of reperfusion. Results Compared with the normal control, DM rats showed significantly increased plasma total cholesterol (TC, 4.63±0.10 mmol/l vs 1.57±0.13 mmol/l, n=8, p<0.05) and triglyceride (TG, 1.13±0.15 mmol/l vs 0.68±0.09 mmol/l, p<0.05). This model also had more severe MI/R injury and cardiac functional impairment. Feeding DM rats with Semen Cassiae extract significantly reduced the plasma TC (2.10±0.33 mmol/l), TG (0.76±0.18 mmol/l), improved the instantaneous first derivation of left ventricle pressure (±LV dP/dtmax, (2854±96) and -(2435±98) mm Hg/s vs. (2686±87) and -(2343±86) mm Hg/s in DM group, n=8), and reduced infarct size ((42.36±9.17)% vs (56.44±10.43)%), plasma creatine kinase and lactate dehydrogenase activities, and apoptotic index ((38.2±7.3) % vs (46.3±6.7) %) at the end of reperfusion (all p<0.05). Moreover, Semen Cassiae extract treatment also increased the antiapoptotic protein Akt and ERK1/2 expression and phosphorylation levels (n=3, p<0.05). Pretreatment with a PI3K inhibitor wortmannin (1.4 mg/kg, i.p., 15 min before ischaemia) or an ERK1/2 inhibitor PD98059 (5 mg/kg, i.p., 15 min before ischaemia) significantly blocked Akt and ERK1/2 phosphorylation respectively and both inhibited the cardioprotective effects induced by Semen Cassiae extract feeding. However, Semen Cassiae extract treatment did not show any effect on the plasma TC/TG levels and MI/R injury in the normal rats. Conclusions Our data suggest that Semen Cassiae extract effectively improves myocardial function and reduces MI/R-induced injury (including apoptosis) in diabetic but not normal rats, which is possibly attributed to the reduced TC/TG levels and the triggered cell survival signalling Akt and ERK1/2.