Growth factors promote the survival and proliferation of human spermatogonium stem cells in vitro / 中华男科学杂志

<p><b>OBJECTIVE</b>To study the effects of growth factors on the survival and proliferation of human spermatogonial stem cells (SSCs) in vitro.</p><p><b>METHODS</b>SSCs were treated with the growth factors SCF, LIF and bFGF added to the culture, each at the concentrations of 0, 5, 10 and 20 microg/L and repeated three times. The survival time and proliferation rate of the cells were determined every 8-12 hours and their morphological features observed with the light microscope and electron microscope.</p><p><b>RESULTS</b>The survival time and proliferation rate of the SSCs were significantly increased in the treated groups as compared with the control (P < 0.05).</p><p><b>CONCLUSION</b>The growth factors SCF, LIF and bFGF can promote the survival and proliferation of SSCs in vitro.</p>

May chronic childhood constipation cause oxidative stress and potential free radical damage to children? / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate whether chronic childhood constipation (CCC) may cause oxidative stress and potential free radical damage to children, and to explore the mechanisms by which CCC may cause oxidative stress and potential free radical damage to chronic constipation patients (CCPs).</p><p><b>METHODS</b>Sixty CCPs and sixty healthy child volunteers (HCVs) whose ages, gender and others were matched for the CCPs were enrolled in a randomized controlled study, in which levels of vitamin C (VC) and vitamin E (VE) in plasma as well as activities of superoxide dismutase (SOD) and catalase (CAT) in erythrocytes were determined by spectrophotometric analytical methods.</p><p><b>RESULTS</b>Compared with average values of the above biochemical parameters in the HCVs group, the average values of VC and VE in plasma as well as those of SOD and CAT in erythrocytes in the CCPs group were significantly decreased (P < 0.0001). Linear regression and bivariate correlation analysis showed that with prolonged course of the CCPs, the levels of VC and VE in plasma as well as the activities of SOD and CAT in erythrocytes in the CCPs were decreased gradually (P < 0.0001).</p><p><b>CONCLUSION</b>The findings in the present study suggest that chronic childhood constipation causes oxidative stress and potential free radical damage to children with chronic constipation.</p>