AIM: To study the changes in capillarity of skeletal muscle during acclimation to high altitude, and explore the effects of a certain extent physical activity under hypoxia on capillary formation and the role of vascular endothelial growth factor (VEGF) in this process. METHODS: 48 Wistar rats were divided into 3 groups: Ⅰ normoxic control; Ⅱ hypoxia and Ⅲ hypoxia+exercise. Rats of Ⅱ and Ⅲ groups were subjected to hypobaric hypoxia for 5 weeks (23 h/d). They were first brought to simulated 4 000 m altitude, where rats of the Ⅲgroup were forced to swim for 1 h/d (6 d/week). Then the animals were ascent to 5 000 m. Biomicrosphere method was used to determine blood flow of skeletal muscle. The mean fiber cross-sectional area (FCSA), capillary density (CD) and capillary/fiber ratio (C/F) of red portion of the lateral head of the gastrocneminus were assayed by myofibrillar ATPase histochemistry. VEGF and its receptor KDR were assayed with immunohistochemistry method.RESULTS: By comparison with the normoxic control, 5-week hypoxic exposure resulted in a decrease in cross-sectional area of skeletal muscle fiber and an increase in CD, but the C/F remained unchanged. The blood supply to the gastrocnemius was not changed. After 5-week-exercise at high altitude, the muscle fibers did not undergo atrophy. CD, C/F, and the blood flow at rest increased significantly. VEGF protein was found primarily in the matrix between muscle fibers; KDR were shown mainly in endothelial cells of capillary. VEGF was more strongly stained in the skeletal muscle of hypoxia-exercise rats.CONCLUSION: Hypoxia itself can not induce neovascularization. While exercise during hypoxic exposure can lead to capillary formation. VEGF and KDR may play roles in it. New capillary formation benefits the blood supply, oxygen delivery and working performance at high altitude.

Background and purpose: MicroRNAs (miRNAs) play an important role in tumor biological behavior. miRNAs are down-regulated or up-regulated in various cancer types, triggering abnormal cell differentiation, proliferation and apoptosis. This study was designed to investigate the expression and clinical signiifcance of miR-187*in colorectal cancer (CRC), and further to investigate its roles in promoting cell apoptosis. Methods:The expressions of miR-187* in 40 CRC cases were examined by real-time quantitative reverse transcription-PCR (qRT-PCR). The relationship between miR-187*expression and clinical features of CRC was analyzed. HCT116 cells were transfected with a miR-187*mimic and the apoptosis of the transfected cells were examined by lfow cytometry (FCM). Results:The expression of miR-187*was down-regulated in CRC tissues 0.165 (0.106, 0.428) compared with those in normal tissues 0.334 (0.211, 0.712) (P<0.05), especially in mucinous carcinoma and older age CRC (P<0.05). Transfection of HCT116 cells with a miR-187*mimic up-regulated the expression of miR-187*and increased cell early apoptosis (P<0.05). Conclusion: The expression level of miR-187* was lower in CRC. miR-187* expression correlates with histological type and age. Transfection of HCT116 cells with a miR-187*mimic accelerates apoptosis of tumor cells, suggesting that miR-187*is a potent tumor suppressor.

AIM: To study the changes in myocardial blood flow (MBF), capillarization and cardiac function in the rat during acclimation to hypoxia. METHODS: Myocardial capillary density (CD) and capillary/myocyte ratio (C/M) was assayed by alkaline phosphatase histochemistry. Biomicrosphere method was used to determine MBF in the rat after 5, 15 or 30 days hypobaric hypoxic exposure (5 000 m). RESULTS: In the course of hypoxia, MBF and cardiac function increased in the right ventricle. However, in the left ventricle, acute hypoxia caused an increase in MBF and a decrease in cardiac function. Both returned to the control level on continued hypoxic exposure. Neovascularization occurred after 15 day or 30 day of hypoxic exposure in both ventricles, judged from the significant increment of C/M ratio albeit the CD remained unchanged in the right ventricle. CONCLUSION: Our findings indicate that adaptive changes in rat heart during acclimation to hypoxia include: ① persistent increase in MBF, hypertrophy associated with increase in capillarity and enhanced cardiac function of the right ventricle; ② increase in MBF and depression of cardiac function at first, then followed by recovery of MBF and increase in capillarity accompanied with recovery of left ventricular function.

Objective To investigate the expression and clinical significance of microRNA-224 and microRNA-378e in colorectal cancer tissues and normal mucosa adjacent to tumor lesions. Methods The gene chip technology was used to detect the different expression of miRNA in colorectal carcinoma tissues and adjacent normal tissues, which was then confirmed by real-time PCR. The relationship between the pathology and clinical data was analyzed. Results The expres-sion level of miR-224 was significantly up-regulated in tumor tissue, while miR-378e was down-regulated in tumor tissue, which was confirmed by real-time PCR. The expression of miR-224 was strongly associated with histological types, while miR-378e was strongly associated with the infiltration depth of colorectal cancer. Conclusion miR-224 is a potent tumor promoter, while miR-378e is a potent tumor suppressor. Both miR-224 and miR-378e can be used as potential colorectal cancer molecular markers.

[ ABSTRACT] AIM:To investigate the depressant effect of FK228 combined with rapamycin on the human breast cancer cell line MCF-7 and MDA-MB-435.METHODS:FK228, a new histone deacetylase inhibitor, and rapamycin, the specific inhibitor of the mammalian target of rapamycin ( mTOR) protein, were used in the study.MCF-7 cells and MDA-MB-435 cells were exposed to different concentrations of FK228 and rapamycin.The inhibitory rate of cell growth was de-termined by SRB assay.Combination index ( CI) was used to evaluate the interaction between FK228 and rapamycin.The expression of the apoptotic proteins, cycle proteins and nucleic acid proteins were detected by Western blotting.The cell cycle was analyzed by flow cytometry.RESULTS: Both FK228 and rapamycin showed growth inhibitory effects on the breast cancer cell lines in a time-and dose-dependent manner.CI of the 2 drugs was less than 1 when the inhibitory rate of the cell growth was 50%effective dose (ED50)~ED70, indicating a synergistic effect.The combination therapy of FK228 with rapamycin increased the apoptotic proteins, and induced the down-regulation of phosphorylated Akt and over-expres-sion of caspase-3 compared with a single use of the drugs.The combination therapy of FK228 with rapamycin reduced the cycle proteins, and the cell cycle was arrested in G2/M.The levels of phosphorylated H2AX and acetylated H3 were ob-viously increased after combination therapy.CONCLUSION:The combination therapy of FK228 with rapamycin inhibits the cell proliferation and increases apoptosis with a synergistic effect, which may become a new trend for treating endometri-al cancer.

OBJECTIVETo optimize the protocols for isolation, in vitro culture, identification and induction of hepatic differentiation of rat bone marrow mesenchymal stem cells (BMSCs).

METHODSRat BMSCs were separated and purified by differential adherent culture for 1.5 h with the first medium change at 12 h. The surface markers of BMSCs were detected by flow cytometry. The cells were induced to differentiate into adipogenic, osteogenic, and chondrogenesis lineages. A 3-step protocol including sequential addition of growth factors, cytokines and hormones was used to induce the BMSCs to differentiate into hepatocyte-like cells.

RESULTSThe cells isolated using this protocol were positive for CD29, CD44, and CD90 and negative for CD29 and CD45. The adipogenic, osteogenic, and chondrogenic differentiation of the BMSCs were verified by Oil red, Alizarin red, and toluidine blue staining. The BMSCs induced with the 3-step protocol differentiated into hepatic-like cells that expressed hepatocyte-specific proteins (ALB and AFP) and genes.

CONCLUSIONThe optimized protocol allows simple and efficient isolation of highly purified populations of BMSCs, which can be induced into hepatic lineages in specific microenvironment.

Animals ; Cell Culture Techniques ; Cell Differentiation ; Flow Cytometry ; Hepatocytes ; cytology ; Mesenchymal Stromal Cells ; cytology ; Rats

Programmed death-1 and programmed death-ligand 1(PD-1/PD-L1)are regulatory immune checkpoint molecules that inhibit T cell activation and,therefore,play an important role in tumor immunotherapy.In recent years,increasing numbers of targeted therapeutic agents have been developed,but single immune checkpoint blockers cannot completely inhibit tumor occurrence,and tumor escape sporadically occurs.Consequently,combination therapy of targeted drugs is considered a useful method to inhibit tumorigenesis and tumor development.T cell immunoglobulin and immunoreceptor tyrosine-based inhibition motif(ITIM)domain(TIGIT)is an inhibitory type 1 poliovirus receptor that has recently been a hotspot of targeted drug therapy research.It has been shown that the combination therapy of TIGIT plus PD-1/PD-L1 can reduce tumor escape and inhibit tumorigenesis more effectively.Therefore,this review summarizes and discusses the progress on the dual blockade of TIGIT and PD-1/PD-L1 pathways in tumor immunotherapy to provide a theoretical basis for tumor im-munotherapy.

OBJECTIVE3-Methylcrotonyl-coenzyme A carboxylase deficiency (MCCD) is an autosomal recessive inborn error of leucine catabolism. The cases suspected as MCCD detected by neonatal screening are not rare. The aim of the study was to investigate the clinical outcomes in cases suspected as MCCD by neonatal screening. The second aim was to investigate the mutation spectrum of MCC gene in Chinese population and hotspot mutation.

METHODForty-two cases (male 33, female 9) , who had higher blood 3-hydroxy-isovalerylcarnitine (C5-OH) levels(cut-off <0.6 µmol/L) detected by neonatal screening using MS/MS, were recruited to this study during Sept.2011 to Mar.2013. The C5-OH concentrations were [0.84 (0.61-20.15) µmol/L] in 42 cases at the screening recall. Five cases were firstly diagnosed as maternal MCCD, 6 cases as benign MCCD and 31 cases were suspected as MCCD. To follow up the height, weight, mental development, blood C5-OH concentrations and urinary 3-methylcrotonyl-glycine (3-MCG) and 3-hydroxy isovalerate (3-HIVA) in order to investigate the clinical outcome. The MCCC1 and MCCC2 gene mutation were analyzed for some cases. The novel gene variants were evaluated, and the influence of novel missense variants on the protein structure and function were predicted by PolyPhen-2, SIFT, UniProt and PDB software.

RESULT(1) Forty-two cases had no symptoms, their physical and mental development were normal in the last visit at the median ages of 29 months, the oldest age of follow up was nearly 9 years. (2) Gene mutation analysis was performed for 29 cases with informed consent signed by parents.Fourteen different mutations were identified in 19 cases. The mutations in MCCC1 gene accounted for 86%, the most common mutation was c.ins1680A, (accounted for 40%). Nine kinds of novel variant were detected including 211AG>CC/p.Q74P, c.295G>A/p.G99S, c.764A>C/p.H255P, c.964G>A/p. E322K, c.1331G>A/p.R444H, c.1124delT, c.39_58del20, c.1518delG, c.639+2T>A.Other 3 kinds of mutation in MCCC1 gene and 2 kinds of mutation in MCCC2 gene have been reported previously; the amino acid of mutant positions of five kinds of novel missense variant are almost highly conserved. These missense variants were predicted to cause change of human MCC protein side chain structure by changing hydrogen bonding, size of amino acid residue and electric charge, and predicted to damage the protein function possibly according to PolyPhen-2 and PDB analysis. So these novel variants may be disease-causing mutations. No mutation were detected in 10 cases. (3) Blood concentrations of C5-OH when screening, recall and end of follow-up in maternal MCCD was 3.50 (1.63-11.43), 1.84 (1.00-9.30), 0.27 (0.26-5.81) µmol/L. There was a significant downward trend.In contrast, benign MCCD group was 8.20 (3.60-9.60), 9.67 (3.88-20.15), 23.0 (5.87-49.10) µmol/L.It showed a rising trend. Children's urinary 3-MCG of benign MCCD group was found abnormally elevated in 4 cases (100%) when they were recalled.

CONCLUSIONA certain number of cases with MCCD or suspected as MCCD in this study had no symptoms and normal physical and mental development after follow-up to oldest age of nearly 9 years. The mutation in MCCC1 gene is common, nine novel mutations were found, c.ins1680A may be a hotspot mutation in Chinese population. The urinary GC/MS analysis and blood MS/MS analysis for mother should be routinely performed for all cases with high blood C5-OH level detected by neonatal screening.

Amino Acid Sequence ; Asian Continental Ancestry Group ; genetics ; Carbon-Carbon Ligases ; blood ; deficiency ; genetics ; Carnitine ; analogs & derivatives ; blood ; Child ; Child, Preschool ; DNA Mutational Analysis ; Female ; Follow-Up Studies ; Humans ; Infant ; Infant, Newborn ; Male ; Mutation ; Neonatal Screening ; Tandem Mass Spectrometry ; Urea Cycle Disorders, Inborn ; blood ; diagnosis ; enzymology ; genetics