ABSTRACT
BACKGROUND: Although birth defects are of great concern globally, the latest national prevalence has not yet been quantified in China. We conducted a systematic review and meta-analysis to estimate the perinatal prevalence of birth defects in the Mainland of China between 2000 and 2021. METHODS: We performed a systematic literature search of six databases for relevant articles published between January 1, 2000, and March 1, 2023. We included published studies that reported data on the perinatal prevalence of birth defects in the Mainland of China. The DerSimonian and Laird random-effects models were used to estimate the pooled prevalence and its 95% confidence interval (CI). We also conducted subgroup analyses and univariable meta-regressions to explore differences in prevalence by time period, geographic region, and other characteristics. RESULTS: We included 254 studies reporting the perinatal prevalence of birth defects and 86 studies reporting only the prevalence of specific types of birth defects. Based on 254 studies covering 74,307,037 perinatal births and 985,115 cases with birth defects, the pooled perinatal prevalence of birth defects was 122.54 (95% CI 116.20-128.89) per 10,000 perinatal births in the Mainland of China during 2000-2021. Overall, the perinatal prevalence of birth defects increased from 95.60 (86.51-104.69) per 10,000 in 2000-2004 to 208.94 (175.67-242.22) per 10,000 in 2020-2021. There were also significant disparities among different geographical regions. Congenital heart defects (33.35 per 10,000), clefts of the lip and/or palate (13.52 per 10,000), polydactyly (12.82 per 10,000), neural tube defects (12.82 per 10,000), and inborn errors of metabolism (11.41 per 10,000) were the five most common types of birth defects. The perinatal prevalence among males was significantly higher than that among females (ß = 2.44 × 10-3, P = 0.003); a higher perinatal prevalence of birth defects was observed among perinatal births whose mothers were ≥ 35 years (ß = 4.34 × 10-3, P < 0.001). CONCLUSION: Comprehensive and sustained efforts are needed to strengthen surveillance and detection of birth defects, improve prenatal and postnatal healthcare, and promote rehabilitation, especially in underdeveloped areas.
ABSTRACT
Introduction: Maternal immune activation (MIA) is closely related to the onset of autism-like behaviors in offspring, but the mechanism remains unclear. Maternal behaviors can influence offspring's development and behaviors, as indicated in both human and animal studies. We hypothesized that abnormal maternal behaviors in MIA dams might be other factors leading to delayed development and abnormal behaviors in offspring. Methods: To verify our hypothesis, we analyzed poly(I:C)-induced MIA dam's postpartum maternal behavior and serum levels of several hormones related to maternal behavior. Pup's developmental milestones and early social communication were recorded and evaluated in infancy. Other behavioral tests, including three-chamber test, self-grooming test, open field test, novel object recognition test, rotarod test and maximum grip test, were performed in adolescence of pups. Results: Our results showed that MIA dams exhibit abnormal static nursing behavior but normal basic care and dynamic nursing behavior. The serum levels of testosterone and arginine vasopressin in MIA dams were significantly reduced compared with control dams. The developmental milestones, including pinna detachment, incisor eruption and eye opening, were significantly delayed in MIA offspring compared with control offspring, while the weight and early social communication showed no significant differences between the two groups. Behavioral tests performed in adolescence showed that only male MIA offspring display elevated self-grooming behaviors and reduced maximum grip. Discussion: In conclusion, MIA dams display abnormal postpartum static nursing behavior concomitantly with reduced serum levels of testosterone and arginine vasopressin, possibly involving in the pathogenesis of delayed development and elevated self-grooming in male offspring. These findings hint that improving dam's postpartum maternal behavior might be a potential regime to counteract delayed development and elevated self-grooming in male MIA offspring.
ABSTRACT
PHA was a kind of biodegradable polymer produced by mixed microorganisms. In recent years, 3-stage PHA synthesis process (including substrate hydrolysis, culture selection, and PHA synthesis) was commonly used for PHA production. In this kind of process, culture selection is the key stage, which directly affects the PHA production efficiency. In order to deal with sludge bulking occurred in the culture selection system, this paper analyzes the influence of substrate concentration on culture selection efficiency as well as operation stability. Under different influent substrate concentrations of 560 mg x L(-1), 1 120 mg x L(-1) and 1 680 mg x L(-1), we confirmed that influent substrate concentration (COD) of 1 120 mg x L(-1) is the most suitable parameter for the bacteria enriching process after a long period of time under short SRT. After 94 days of cultivation, we achieved 50% of PHA content, 0.7145 COD/COD of PHA conversion rate and 0.191 2 mg x (mg x h)(-1) of specific PHA storage rate at the end of batch tests with nutrient starvation. The study also confirmed that glycogen level in cells has a close relationship with its PHA synthesis ability, which shows its potential to predict the enrichment efficiency.
