Prevalence of preterm birth and risk factors associated with it at different gestational ages: A multicenter retrospective survey in China.

OBJECTIVES: To investigate the prevalence of preterm birth (PTB) and the risk factors for different gestational age subgroups of preterm birth in China. METHODS: We carried out a descriptive cross-sectional study encompassing all singleton live births (24+0 to 41+6 weeks) with completed data in 23 provinces in China from 2010 to 2017 during investigation period. We compared both the preterm group (24+0 to 36+6 weeks) and preterm subgroups (<32 weeks, 32+0 to 33+6 weeks, and 34+0 t0 36+6 weeks) with the term group (37+0 to 41+6 weeks). We collected information on maternal and fetal characteristics from medical records. Logistic regression was use. RESULTS: The prevalence of PTB was 7.4% (15,833/215,254) in singleton births. After adjusting for maternal age, parity, and potential risk factors in univariate analysis, the high-risk factors for PTB at <32 weeks were placental abruption (aOR=41.52; 95% CI, 25.89-66.58), placenta previa (aOR=40.04; 95% CI, 32.00-50.09), chorioamnionitis (aOR=11.06; 95% CI, 8.738-14.02), and hypertension disorders in pregnancy (HDP) (aOR=3.564; 95% CI, 2.930-4.335). Intrahepatic cholestasis of pregnancy (ICP) was significantly associated with PTB at 34-36 weeks (aOR=5.763; 95% CI, 5.049-6.577), particularly with spontaneous PTB (aOR=10.04; 95% CI, 8.79-11.47). Gestational diabetes mellitus (GDM) was significantly associated with PTB at 34-36 weeks only (aOR=1.156; 95% CI, 1.054-1.267). CONCLUSION: Placental abruption, placenta previa, chorioamnionitis, and HDP were more predictive of early PTB; GDM and ICP were more predictive of late PTB.

Ancient DNA and multimethod dating confirm the late arrival of anatomically modern humans in southern China.

The expansion of anatomically modern humans (AMHs) from Africa around 65,000 to 45,000 y ago (ca. 65 to 45 ka) led to the establishment of present-day non-African populations. Some paleoanthropologists have argued that fossil discoveries from Huanglong, Zhiren, Luna, and Fuyan caves in southern China indicate one or more prior dispersals, perhaps as early as ca. 120 ka. We investigated the age of the human remains from three of these localities and two additional early AMH sites (Yangjiapo and Sanyou caves, Hubei) by combining ancient DNA (aDNA) analysis with a multimethod geological dating strategy. Although U-Th dating of capping flowstones suggested they lie within the range ca. 168 to 70 ka, analyses of aDNA and direct AMS 14C dating on human teeth from Fuyan and Yangjiapo caves showed they derive from the Holocene. OSL dating of sediments and AMS 14C analysis of mammal teeth and charcoal also demonstrated major discrepancies from the flowstone ages; the difference between them being an order of magnitude or more at most of these localities. Our work highlights the surprisingly complex depositional history recorded at these subtropical caves which involved one or more episodes of erosion and redeposition or intrusion as recently as the late Holocene. In light of our findings, the first appearance datum for AMHs in southern China should probably lie within the timeframe set by molecular data of ca. 50 to 45 ka.

Pregnancy induced hypertension and outcomes in early and moderate preterm infants.

OBJECTIVE: To identify the effect of pregnancy induced hypertension on neonatal outcomes in early and moderate preterm infants of gestational age less than 34 weeks. STUDY DESIGN: Prospectively collected data in 773 premature deliveries less than 34 weeks from 10 centers in China between July 2014 and July 2016 were analyzed in this cohort study. Univariate and Multivariate regression analyses were conducted to exam the effect of pregnancy induced hypertension on neonatal outcomes, including mortality to discharge, intrauterine growth restriction, severe brain injury, neonatal respiratory distress syndrome, bronchopulmonary dysplasia, necrotizing enterocolitis, early onset of sepsis and retinopathy of prematurity. RESULTS: The incidence of PIH in this cohort was 18.4%. Women with PIH tended to have a higher cesarean delivery rate (78.2% vs 40.9%, P < 0.001). More tocolytics and magnesium sulfate were used in PIH women (72.5% vs 48.7%, P < 0.001; 59.2% vs 34.7%, P < 0.001). Mean birth weight was lower in infants of PIH mothers than infants of non-PIH mothers (1522.1 ±â€¯348.8 g vs 1683.4 ±â€¯345.3, P < 0.001). In multivariate regression models, PIH was associated with increased risk of IUGR (OR 8.402; 95% CI 4.350-16.227) and lower odds of NRDS (OR 0.526; 95% CI 0.332-0.853). CONCLUSION: Preterm infants less than 34 weeks born to PIH women had a higher risk of intrauterine growth restriction and lower birth weight. PIH warrants more intensive interventions to prevent relevant infant morbidities.

Effects of preweaning environmental enrichment on hippocampus-dependent learning and memory in developing rats.

Previous studies have shown that environmental enrichment (EE) improves learning and memory in adult animals. However, the effects of preweaning EE (preEE) on hippocampus-dependent learning and memory as well as its possible mechanisms are poorly understood. Here we report that preEE enhanced the exploratory activity in rats immediately after weaning, and the EE group showed greater performance in a passive avoidance task than the control group (p<0.05), but not in the locomotion activity. Electrophysiology analysis showed that rats exposed to preEE exhibited larger field excitatory postsynaptic potentials after long-term potentiation induction than those in the control group (p<0.05). The protein levels of phosphorylated extracellular signal-regulated kinases as well as activity-regulated cytoskeleton-associated protein were significantly upregulated in the preEE group compared to the control group (p<0.05). Our results indicate that preEE can enhance hippocampus-dependent learning and memory function as postweaning EE does, and the upregulated activation of the ERK signal transduction pathway may be the underlying molecular mechanism.

[Clinical features and follow-up study of neonatal asymmetric crying facies].

OBJECTIVE: To evaluate the clinical characteristics and short-term outcomes of neonatal asymmetric crying facies (ACF), in order to improve recognition of the disease. METHODS: The clinical data of 11 infants with ACF between January 2010 and February 2012 were retrospectively studied. Physical and neurological development were followed up at correct gestational age 44 weeks and 3 months. RESULTS: Of the 11 infants with ACF, 4 had ipsilateral ear malformation, 2 had congenital heart disease and 1 had syndactyly and polydactyly. Of the 11 infants, 8 were male and 3 were female. Eight infants presented with lesions on the left side and 3 presented with lesions on the right. The fathers were aged over 35 in 8 cases and the mothers were over 30 in 7 cases. Eight mothers had a history of at least 3 pregnancies and 2 infants were born to mothers with diabetes mellitus. Physical index was below P10 in 1 case and 2 cases showed a low NBNA score and mild abnormal GMs (poor repertoire PR) during the writhing period at correct gestational age 44 weeks. Physical index was between P10-P90 and GM assessment during the fidgety period showed normal movements in all infants at correct gestational age 3 months, but they still had ACF. CONCLUSIONS: ACF is associated with a high rate of other congenital malformations. The short-term outcomes of ACF infants are satisfactory, but long-term follow-up and interdisciplinary cooperation are necessary to improve prognosis.

Calmodulin activation is required for the enhancement of hippocampal neurogenesis following environmental enrichment.

OBJECTIVE: An enriched environmental exposure has been shown to promote hippocampal neurogenesis, which is an important mechanism underlying enrichment-induced memory improvement. The cAMP response element-binding protein is an important stimulus-inducible factor in the brain and is crucial for neurogenesis and memory ability. Calmodulin activation is important for activity-induced cAMP response element-binding protein phosphorylation. The aim of this study was to explore the effects of calmodulin activation on hippocampal neurogenesis and spatial memory improvement in rats exposed to enriched environment. METHODS: Ninety-six neonatal pups were assigned to four groups: control group, enriched environment group, control + trifluoperazine (trifluoperazine, 5 mg/kg) group and enriched environment + trifluoperazine group. Pups in the enriched environment and enriched environment + trifluoperazine groups were exposed to enriched environments for 25 min from P10 to P24. Half of pups in each group were intraperitoneally injected with 50 mg/kg BrdU every other day from P10 to P24. Pups without BrdU injection were euthanized at P24, and hippocampal nuclear Ca(2+)-calmodulin and phosphorylated cAMP response element-binding protein were detected. Morris water maze acquisition and subsequent probe trial retention were performed in remained rats after P50 and immunohistochemistry was used to identify proliferating cells in the dentate gyrus 1 day after the probe trial. RESULTS: The trifluoperazine injection could completely inhibit the environmental enrichment-induced activations of calmodulin and cAMP response element-binding protein. Enriched environmental exposure could improve Morris water maze performance and increase hippocampal BrdU-labeled cells, but the effects could be completely blocked by trifluoperazine injection. CONCLUSION: This study proves that the activation of calmodulin is essential for an enriched environmental exposure-induced cAMP response element-binding protein activation, hippocampal neurogenesis and spatial memory improvement.

[Effects of preweaning enrichment on activity-regulated cytoskeletal protein expression and long-term memory in rats].

OBJECTIVE: To investigate the effects of preweaning enrichment on the expression of activity-regulated cytoskeletal protein (Arc), an immediate early gene, and on the long-term memory in rats. METHODS: Forty neonatal Sprague-Dawley rats were randomly assigned to control group (standard environment, n=20) and experimental group (enriched environment, n=20). The experimental group received enriched environment exposure from postnatal day 10 until weaning (2 weeks, 20 minutes per day). The open field and novel object recognition tests were performed at postnatal day 28. Arc expression was detected by Western blotting and immunohistochemistry. RESULTS: There was no significant difference in the open field test between the two groups. However, in the novel object recognition test, the experimental group rats performed significantly better than the control rats after 1 and 24-hr retention. The preference index in the experimental group after 1-hr (59.61%+/-9.61% vs 50.46%+/-9.34%; P<0.05) and 24-hr retention (62.72%+/-14.12% vs 52.39%+/-9.16%; P<0.05 ) was significantly higher than that in the control group. Arc expression in both areas CA1 and DG of hippocampus in the experimental group increased significantly compared with that in the control group (P<0.01). CONCLUSIONS: Preweaning enrichment can up-regulate the expression of immediate early gene, Arc, in the hippocampus of the rats, and promote their long-term memory.

[Preweaning exposure to enriched environment induces hippocampal neurogenesis: experiment with rats].

OBJECTIVE: To explore the effects of preweaning exposure to enriched environment on hippocampal neurogenesis and the underlying mechanisms. METHODS: Thirty-six 10-day-old SD rats were randomly divided into the 2 equal groups: control group and enriched environment group (EE group. From the age of 10 days to 24 days the rats received intraperitoneal injection of bromodeoxyuridine (BrdU) 50 mg/kg every other day to label the newly proliferated cells in vivo, and the rats in EE group were daily exposed to enriched environment for 20 minutes. Six rats of each group were sacrificed whren they were 24 days of age. Nuclear protein of the hippocampus was extracted to undergo Western blotting to detect the levels of calmodulin and phosphorylated CREB (cAMP response element binding). Other rats were sacrificed at the age of 63 days. Coronal cryostat sections of brain were cut. Sections at the level 3.6 mm posterior to the bregma were obtained and stained with methyl aniline blue and the number of cells in the hippocampal dentate gurus (DG) of the right hemisphere were counted using x 400 microscope. BrdU immunohistochemistry and double immunofluorescence labeling with BrdU/NeuN or BrdU/GFAP were done, and the numbers of BrdU-labeled cells and ratios of neurons and astrocytes differentiated from BrdU-labeled cells were calculated. RESULTS: The levels of calmodulin and phosphorylated CREB in the hippocampal nuclear extract of the EE group were 0.065 +/- 0.035 and 0.485 +/- 0.007 respectively, both significantly higher than those of the control group (0.245 +/- 0.035 and 0.220 +/- 0.014 respectively, P = 0.01 and P = 0.002). The number of cells in the DG area of right hippocampus 3.6 mm posterior to bregma of the EE group was 1580 +/- 72, significantly higher than that of the control rats (1375 +/- 62, t = -7.461, P < 0.01). The number of BrdU labeled cells of the EE group was 5363 +/- 487, significantly higher than that of the control group (2984 +/- 318, t = -14.177, P < 0.01). The ratio of neurons of the EE group was 85.0% +/- 2.8%, significantly higher than that of the control group (80.2% +/- 2.8%, t = -4.166, P < 0.01). The differentiation rate of astrocytes of the EE group was 4.0% +/- 0.5%, significantly higher than that of the control group (2.6% +/- 0.6%, t = -6.493, P < 0.01). CONCLUSION: Preweaning exposure to enriched environment can induce neurogenesis. The underlying mechanism may be that enriched environment induces the activation of calmodulin and CREB in hippocampus.