[Effects of interpregnancy interval on pregnancy outcomes of subsequent pregnancy: a multicenter retrospective study].

Objective: To explore the effects of interpregnancy interval (IPI) on pregnancy outcomes of subsequent pregnancy. Methods: A multicenter retrospective study was conducted in 21 hospitals in China. Information of age, height, pre-pregnancy weight, IPI, history of diseases, complications of pregnancy, gestational age of delivery, delivery mode, and pregnancy outcomes of the participants were collected by consulting medical records of pregnant women who had two consecutive deliveries in the same hospital during 2011 to 2018. The participants were divided into 4 groups according to IPI:<18 months, 18-23 months, 24-59 months and ≥60 months. According to the WHO's recommendation, with the IPI of 24-59 months group as a reference, to the effects of IPI on pregnancy outcomes of subsequent pregnancy were analyzed. Stratified analysis was further carried out based on age, history of gestational diabetes mellitus (GDM), macrosomia, and premature delivery, to explore the differences in the effects of IPI on pregnancy outcomes among women with different characteristics. Results: A total of 8 026 women were included in this study. There were 423, 623, 5 512 and 1 468 participants in <18 months group, 18-23 months group, 24-59 months group and ≥60 months group, respectively. (1) The age, pre-pregnancy body mass index (BMI), history of cesarean section, GDM, gestational hypertension and cesarean section delivery rate of <18 months group, 18-23 months group, 24-59 months group and ≥60 months group were gradually increased, and the differences were statistically significant (P<0.05). (2) After adjusting for potential confounding factors, compared with women in the IPI of 24-59 months group, the risk of premature delivery, premature rupture of membranes, and oligohydramnios were increased by 42% (OR=1.42, 95%CI: 1.07-1.88, P=0.015), 46% (OR=1.46, 95%CI: 1.13-1.88, P=0.004), and 64% (OR=1.64, 95%CI: 1.13-2.38, P=0.009) respectively for women in the IPI≥60 months group. No effects of IPI on other pregnancy outcomes were found in this study (P>0.05). (3) After stratified by age and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months would significantly increase the risk of oligohydramnios for women with advanced age (OR=2.87, 95%CI: 1.41-5.83, P=0.004); and <18 months could increase the risk of premature rupture of membranes for women under the age of 35 (OR=1.59, 95%CI: 1.04-2.43, P=0.032). Both the risk of premature rupture of membranes (OR=1.58, 95%CI: 1.18-2.13, P=0.002) and premature delivery (OR=1.52, 95%CI: 1.07-2.17, P=0.020) were significantly increased in the IPI≥60 months group. After stratified by history of GDM and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months would lead to an increased risk of postpartum hemorrhage for women with a history of GDM (OR=5.34, 95%CI: 1.45-19.70, P=0.012) and an increased risk of premature rupture of membranes for women without a history of GDM (OR=1.44, 95%CI: 1.10-1.90, P=0.009). After stratified by history of macrosomia and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months could increase the proportion of cesarean section for women with a history of macrosomia (OR=4.11, 95%CI: 1.18-14.27, P=0.026) and the risk of premature rupture of membranes for women without a history of macrosomia (OR=1.46, 95%CI: 1.12-1.89, P=0.005). After stratified by history of premature delivery and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months would significantly increase the risk of premature rupture of membranes for women without a history of premature delivery (OR=1.47, 95%CI: 1.13-1.92, P=0.004). Conclusions: Both IPI≥60 months and <18 months would increase the risk of adverse pregnancy outcomes in the subsequent pregnancy. Healthcare education and consultation should be conducted for women of reproductive age to maintain an appropriate IPI when they plan to pregnant again, to reduce the risk of adverse pregnancy outcomes in the subsequent pregnancy.

Social contact patterns of school-age children in Taiwan: comparison of the term time and holiday periods.

School closure is one of the most common interventions in the early weeks of an influenza pandemic. Few studies have investigated social contact patterns and compared individual student contact characteristics during the school term and holiday periods in Taiwan. Here, we conducted a well-used questionnaire survey in a junior high school (grades 7-8) in June 2013. All 150 diary-based effective questionnaires covering conversation and skin-to-skin contact behaviour were surveyed. Two questionnaires for each participant were designed to investigate the individual-level difference of contact numbers per day during the two periods. The questionnaire response rate was 44%. The average number of contacts during term time (20·0 contacts per day) and holiday periods (12·6 contacts per day) were significantly different (P < 0·05). The dominant contact frequencies and duration were everyday contact (89·10%) and contacts lasting less than 5 minutes (37·09%). The greatest differences occurred within the 13-19 years age groups. The result presented in this study provide an indication of the likely reduction in daily contact frequency that might occur if a school closure policy was adopted in the event of an influenza pandemic in Taiwan. Comparing contact patterns during term time and holiday periods, the number of contacts decreased by 40%. This study is the first research to investigate the contact numbers and contact characteristics for school-age children during the school term and a holiday period in Taiwan. With regard to public health, this study could provide the basic contact information and database for modelling influenza epidemics for minimizing the spread of influenza that depends on personal contacts for transmission.

Epigenetic changes of histone deacetylation in murine oocytes matured in vitro versus in vivo.

OBJECTIVE: In this study, we studied changes in histone acetylation during mouse oocytes meiosis. The aim was to investigate HDAC1 expression patterns in the mouse oocytes and effects of in-vitro maturation on epigenetic modifications during meiosis. MATERIALS AND METHODS: Immature and mature oocytes were collected from female Kunming white mice of 4-6 weeks in age. Dynamic changes of histone H3K9, H4K12 acetylation were explored. HDAC1 spatial and temporal expression patterns during meiosis and their expression changes in in-vitro maturation were determined. RESULTS: It was found that histone H3K9 and H4K12 acetylations were gradually disappeared during the meiotic maturation of mouse oocytes. HDAC1 proteins were localized mainly throughout the nucleoplasm in GV-intact oocyte, and colocalized with chromosomes at metaphase II (MII). The acetylated H3K9 and H4K12 were absent in oocytes matured in vivo, while the elevated acetylation of H3K9 and H4K12 was detected in oocytes matured in vitro. When cultured in vitro, the decrease of HDAC1 protein level and mRNA level were observed compared with oocytes matured in vivo. CONCLUSIONS: the acetylation of H3K9, H4K12 decreased gradually to undetectable during oocyte meiosis. The histone deacetylation in oocytes was inadequate during in vitro maturation, and the in vitro maturation might lead to reduced HDAC1 expression in oocytes.

Effect of berberine alone or in combination with argon ion laser treatment on 9L rat glioma cell line.

The cell-killing effect and its possible mechanism of berberine used alone or in combination with argon ion laser treatment on 9L rat glioma cells were studied. The survival fraction of 9L cells after single treatment of berberine has been investigated using both colony formation and microtitration (MTT) method, the half lethal dose of berberine (LD50) has been estimated to be 60 micrograms/ml. After the addition of low energy laser treatment, the LD50 of berberine markedly decreased to 10 micrograms/ml. The inhibitory effect of berberine on biosynthesis for DNA, RNA, and protein of 9L cells was enhanced by argon ion laser. Moreover, when morphologic change was examined, the 9L cells showed lysis, encystation, and degeneration after berberine treatment; the laser treatment enhanced the cell-killing effect. The study proves the cell-killing effect of berberine combined with laser treatment on 9L rat glioma cell line, hence introducing the possibility of berberine as a photosensitive agent.