Secular trends of age at menarche and age at menopause in women born since 1951 from a county of Shandong Province, China / 北京大学学报(医学版)

OBJECTIVE@#To describe the secular trends of age at menarche and age at natural menopause of women from a county of Shandong Province.@*METHODS@#Based on the data of the Premarital Medical Examination and the Cervical Cancer and Breast Cancer Screening of the county, the secular trends of age at menarche in women born in 1951 to 1998 and age at menopause in women born in 1951 to 1975 were studied. Joinpoint regression was used to identify potential inflection points regarding the trend of age at menarche. Average hazard ratios (AHR) of early menopause among women born in different generations were estimated by performing multivariate weighted Cox regression.@*RESULTS@#The average age at menarche was (16.43±1.89) years for women born in 1951 and (13.99±1.22) years for women born in 1998. The average age at menarche was lower for urban women than that for rural women, and the higher the education level, the lower the average age at menarche. Joinpoint regression analysis identified three inflection points: 1959, 1973 and 1993. The average age at menarche decreased annually by 0.03 (P < 0.001), 0.08 (P < 0.001), and 0.03 (P < 0.001) years respectively for women born during 1951-1959, 1960-1973, and 1974-1993, while it remained stable for those born during 1994-1998 (P=0.968). As for age at menopause, compared with women born during 1951-1960, those born during 1961-1965, 1966-1970 and 1971-1975 showed a gradual decrease in the risk of early menopause and a tendency to delay the age at menopause. The stratified analysis presented that the risk of early menopause gradually decreased and the age of menopause showed a significant delay among those with education level of junior high school and below, but this trend was not obvious among those with education level of senior high school and above, where the risk of early menopause decreased and then increased among those with education level of college and above, and the corresponding AHRs were 0.90 (0.66-1.22), 1.07 (0.79-1.44) and 1.14 (0.79-1.66).@*CONCLUSION@#The age at menarche for women born since 1951 gradually declined until 1994 and leveled off, with a decrease of nearly 2.5 years in these years. The age at menopause for women born between 1951 and 1975 was generally delayed over time, but the trend of first increase and then decrease was observed among those with relatively higher education levels. In the context of the increasing delay in age at marriage and childbearing and the decline of fertility, this study highlights the necessity of the assessment and monitoring of women' s basic reproductive health status, especially the risk of early menopause.

Proliferation of neural progenitor cells in the subventricular zone and around the hematoma after intracerebral hemorrhage in adult rat / 南方医科大学学报

<p><b>OBJECTIVE</b>To examine the proliferation of the neural progenitor cells in the subventricular zone (SVZ) and around the hematoma after intracerebral hemorrhage (ICH) in adult rats.</p><p><b>METHODS</b>ICH was induced by stereotactic injection of type VII collagenase into the corpus striatum of adult rats, followed by pulse or continuous intrapenitoneal injection of bromodeoxyuridine (Brdu) to label the proliferating cells. The rats were sacrificed on days 2, 7, 14 and 28 following the ICH for immunohistochemistry of the tissues in the SVZ and around the hemotoma to determine the number of Brdu- immunoreactive cells.</p><p><b>RESULTS</b>With pulse Brdu labeling, a significant increase in the number of Brdu-immunoreactive cells in the ipsilateral and contralateral tissues in the SVZ and around the hematoma was observed 2-14 days, and the cell number reached the maximum on day 7 after ICH as compared with that of the sham-operated group. With continuous Brdu injection, the increase was observed on day 14 after ICH, and till day 28, the Brdu-immunoreactive cells in the SVZ decreased to the control level, but some positive cells still persisted in the tissues around the hematoma.</p><p><b>CONCLUSION</b>ICH induces transient and regional increase in the cell proliferation in the ipilateral and contraletral SVZ and tissues around the hematoma, and the proliferating cells in the SVZ may migrate towards the hematoma area.</p>

Effect of rat mesenchymal stem cells on hematopoietic reconstitution after allogeneic co-transplantation with bone marrow / 中国实验血液学杂志

To investigate effects of rat bone marrow mesenchymal stem cells (rBMMSC) on hematopoiesis after allo-hematopoietic stem cell transplantation (HSCT), allogeneic BMT model from Fischer 344 rats (RT-1Al) to Wistar rats (RT-1Au) was established; effects of MSCs on hematopoietic reconstitution were studied by survival rate, peripheral blood counts, histological analysis and FACS at day 30 after transplantation. The results showed that (1) MSCs from donor Fisher344 could survive in recipient irradiated by lethal dose and could be found in the thymus, spleen and bone marrow of the recipient at 30 days after cotransplantation with BM by measuring EGFP gene. (2) Cotransplanation of MSCs and BM improved hematopoietic reconstitution. Lymphocyte and platelet counts of peripheral blood in cotransplantation group were higher than those in the control group. Active hematopoiesis and increase of bone marrow nucleated cells were observed in cotransplantation group. MSCs significantly enhanced hematopoiesis of B lymphocyte and megakaryocytopoietic lineages by FACS analysis. It is concluded that (1) MSCs of Fisher344 can be found in the thymus, spleen, bone marrow of the recipients at 30 days after cotransplantion by measuring EGFP gene. (2) hematopoietic reconstitution is significantly enhanced by MSCs cotransplanted with BM.