BACKGROUND: Restriction is a reliable means in the study of psychological stress, and restriction stress can suppress cellular immunity of T lymphocytes through hypothalamus-pituitary-adrenal axis.OBJECTIVE: To investigate the changes of Th1/Th2 balance due to restriction stress in cancer-loaded rats and the growth of cancer so as to explore the effect of psychological stress on cancer cells.DESIGN:Case control study based on experimental animal as subjects.SETTING: Teaching and Research Department of Microbiology and Immunology of Beijing University of Traditional Chinese Medical.MATERIALS: This study was carried out in the Immunology Laboratory of Beijing Traditional Chinese Medical University. Kunming rats of 6-8weeks old were selected. They were raised for 3 days before experiment to adapt to the environment and numbered according to their weight. Rats with the highest and lowest body weight were excluded, and the rest were randomly divided into 4 groups of 16 rats (8 male rats and 8 female rats)weighing 18 to 20 g.METHODS: S180 cancer cells were collected at 7 days of celiac subculture and rinsed with normal saline before made into cell suspensions of 1×1010 L-1 with RPMI 1640 medium. Rats were given subcutaneous injection of 0.2 mL cell suspension at the right axilla in cancer group and cancer-combined restriction group. Meanwhile, the same dosage of normal saline was used instead in normal control group and pure restriction group in the same way. After injection, movements of rats in pure restriction group and cancer-combined restriction group were restricted in specially-made tubes for 8 hours a day. Ten days later rats were killed to remove the tumor and thymus which were then weighed for calculating the thymus index. MTT colorimetry and mitogen-activated immunoblast method were used to examine the proliferation of spleen T lymphocytes and the production of Thl-type cytokines, such as interleukin-2(IL-2), interferon-γ (IFN-γ); meanwhile,ELISA technique was used to detect the level of serum Th2-type cytokines,such as interleukin-4(IL-4) and interleukin-10(IL-10).MAIN OUTCOME MEASURES: Primary outcomes: effect of restriction stress on T lymphocyte' production of IL-2 and interferon-γ, and on IL-4and IL-10 as well as the effect in promoting the cancer growth in cancer-loaded rats. Secondary outcomes: effect of restriction stress on T-lymphocyte proliferation and thymus index.RESULTS: Restriction stress significantly increased the cancer weight and decreased thymus index and the proliferation of spleen T lymphocytes. Meanwhile, IL-2 and IFN-γ produced by spleen cells also decreased, with serum IL-4 and IL-10 level obviously increased in cancer-loaded rats.CONCLUSION:The cellular immunity of cancer-loaded rats was obviously suppressed due to restriction stress, which was presented by decreased Thl-type cytokine production and increased Th2-type cytokine production,resulting in Thl/Th2 cytokine imbalance towards Th2. It may be the important mechanism of its promoting effect on the growth of cancer.

Objective To study the changes of mRNA expression of heat shock protein 70 (HSP70) in the rat brain exposed to repeated +Gz. Method The mRNA expression levels of HSP70 in rat brain were measured by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). Result The HSP70 mRNA expression levels in rat brains taken 30 min and 6 h after repeated +Gz exposures were significantly higher than those in control group, while the difference between the levels of control group and those of experimental rat brains taken 24 h after +Gz exposure was not significant. Conclusion It is suggested that HSP70 mRNA expression in rat brain can be induced by repeated +Gz exposures and the increased HSP70 mRNA expression may play an important role in self-protection against brain damage induced by+Gz exposures.

Objective To investigate the effects of ginsenoside Rg3 on growth and apoptosis of gastric cancer cell line MKN-45 and SGC-7901 in vitro. Methods MKN-45 and SGC-7901 cells at logarithmic growth phase were obtained, and were cultured with ginsenoside Rg3 of different concentrations (20, 30, 40, 50 μg/mL) for 24, 48 h or 24, 48 and 72 h. Cells cultured without ginsenoside Rg3 were served as controls. The inhibition rates of ginsenoside Rg3 on MKN-45 and SGC-7901 cells were detected by MTT assay, apoptosis rate of SGC-7901 cells was determined by Annexin V/PI double staining flow cytometry, cell cycles of SGC-7901 cells were analysed by flow cytometry, and morphological changes of SGC-7901 cells in 50 μg/mL ginsenoside Rg3 treatment group were observed by transmission electron microscopy. Results The inhibition rates on MKN-45 and SGC-7901 cells in each ginsenoside Rg3 treatment group were significantly higher than those in control group (P < 0.05), and the inhibition rates increased with the concentrations of ginsenoside Rg3 and time of culture ( P < 0.05). Compared with control group, the apoptosis rates of SGC-7901 cells and percentages of cells in G_1/G_1 cell cycle in each ginsenoside Rg3 treatment group were significantly increased in a concentration and time dependent manner. Typical morphology of SGC-7901 cell apoptosis was observed by transmission electron microscopy in 50 μg/mL ginsenoside Rg3 treatment group. Conclusion Ginsenoside Rg3 has significant inhibition effect on gastric cancer cell lines in vitro with a concentration and time dependent manner, the mechanism of which may involve the induction of gastric cell line apoptosis.

dosage ( P<0.01).Conclusion UVA can inhibit the proliferation activity of human skin fibroblasts. It might be related to the up-regulation of iNOS gene expression and the over-secretion of NO induced by UVA.

Objective To evaluate the effects of carvedilol on left ventricular function by MPI in patients with heart failure.Methods All the cases came from the first Affiliated Hospital of Harbin Medical University during 2004 to 2006.There were two groups:45 Carvedilol treated patients and 50 placebo controlled patients.The patients with heart failure were detected the conventional Tei index(c-Tei),the tissue Doppler Tei index(t-Tei)and left ventricular ejection fraction pretherapy and post-treatment 1 month and 6 month.Results The patients with heart failure were higher in LVEDd,c-Tei,t-Tei and lower in LVEF compared with the controlled patients(P

OBJECTIVE: To survey on men who have sex with men (MSM) population's sexual behaviors, condom-service condition, HIV related knowledge and other issues among MSM population at sexually transmitted disease (STD) clinics to understand the characteristics of behaviors and offer suggestions for effective health education and behavior intervention. METHODS: From January to December, 2009, we used anonymous questionnaires which involved in their mastery of demographic characteristics, sexual behavior, condom-service condition, HIV related knowledge, and so one, to investigate 200 MSM at 3 STD clinics of comprehensive hospital. RESULTS: The average age of informant was (26.7+/- 8.9) years and 121 individuals (62.6%) had confirmed with STD in recent one year. In the recent 6 months, the average number of homosexual partners was 9.2+/- 4.8 and 102 (52.8%) had heterosexual partners. In the sexual intercourse with homosexual, 123 individuals had anal intercourse (63.7 %) and 117 had oral intercourse (60.6%). In the sexual intercourse with heterosexual, 92 (90.2%) individuals had vaginal intercourse, 37 (36.2%) had anal intercourse, and 59 (57.8%) had oral sex behavior.There were a statistical difference between heterosexual and homosexual sex behaviors (P<0.01). The condom-using frequency had statistic difference in different sexual behaviors(χ²=188.396, P<0.001). There was no linear correlation between HIV related knowledge and condom-using condition in sexual behaviors except the heterosexual anal intercourse. CONCLUSION High AIDS knowledge mastery rate is found in our survey. The respondents get HIV/AIDS knowledge through various ways actively. There is no obvious relation between the mastery of HIV related knowledge and condom-using frequency. The ratio of non-protected sexual behaviors is high in heterosexuals. How to adopt effective methods for behavior intervention to MSM at STD clinic needs to be further studied.
Acquired Immunodeficiency Syndrome ; prevention & control ; transmission ; Adolescent ; Adult ; China ; epidemiology ; Condoms ; statistics & numerical data ; Female ; Health Knowledge, Attitudes, Practice ; Homosexuality, Male ; Humans ; Incidence ; Male ; Middle Aged ; Safe Sex ; Sexual Behavior ; Sexually Transmitted Diseases ; epidemiology ; Surveys and Questionnaires ; Young Adult