Spatial-temporal distribution of preterm birth in China, 1990-2020: A systematic review and modelling analysis.

BACKGROUND: Little is known about the long-term trends of preterm birth rates in China and their geographic variation by province. OBJECTIVES: To estimate the annual spatial-temporal distribution of preterm birth rates in China by province from 1990 to 2020. DATA SOURCES: We searched PubMed, EMBASE, Web of Science, CNKI, WANFANG and VIP from January 1990 to September 2023. STUDY SELECTION AND DATA EXTRACTION: Studies that provided data on preterm births in China after 1990 were included. Data were extracted following the Guidelines for Accurate and Transparent Health Estimates Reporting. SYNTHESIS: We assessed the quality of each survey using a 9-point checklist. We estimated the annual preterm birth risk by province using Bayesian multilevel logistic regression models considering potential socioeconomic, environmental, and sanitary predictors. RESULTS: Based on 634 survey data from 343 included studies, we found a gradual increase in the preterm birth risk in most provinces in China since 1990, with an average annual increase of 0.7% nationally. However, the preterm birth rates in Inner Mongolia, Hubei, and Fujian Province showed a decline, while those in Sichuan were quite stable since 1990. In 2020, the estimates of preterm birth rates ranged from 2.9% (95% Bayesian credible interval [BCI] 2.1, 3.8) in Inner Mongolia to 8.5% (95% BCI 6.6, 10.9) in Jiangxi, with the national estimate of 5.9% (95% BCI 4.3, 8.1). Specifically, some provinces were identified as high-risk provinces for either consistently high preterm birth rates (e.g. Jiangxi) or relatively large increases (e.g. Shanxi) since 1990. CONCLUSIONS: This study provides annual information on the preterm birth risk in China since 1990 and identifies high-risk provinces to assist in targeted control and intervention for this health issue.

Associations between maternal exposure to air pollution during pregnancy and trajectories of infant growth: A birth cohort study.

OBJECTIVE: We examined the relationships between infants' growth trajectories and prenatal exposure to air pollution, which is still under-investigated. METHODS: A birth cohort study was constructed using medical records of pregnant women and infants born between 2015 and 2019 in Foshan, China. Using satellite-based spatial-temporal models, prenatal exposure to air pollutants including particulate matter with an aerodynamic dimension of < 2.5 µm (PM2.5), sulfur dioxide (SO2), nitrogen dioxide (NO2), and ozone (O3) was assessed at each woman's residence. Latent class growth modeling was used to identify trajectories of physical (body length and weight) growth and neurodevelopment, which were repeatedly measured within 1 year after birth. Logistic regression models were used to investigate the associations between prenatal exposure to air pollution and the risks of growth disorders, adjusting for an array of potential confounders. RESULTS: We identified two growth trajectories for body length [normal: 3829 (93%); retardation: 288 (7%)], three for weight [normal: 2475 (59.6%); retardation: 390 (9.4%); overgrowth: 1287 (31%)], and two for neurodevelopment [normal: 956 (66.1%); retardation: 491 (33.9%)]. For exposure over whole pregnancy, SO2 was associated with an increased risk of body length retardation (OR for per 1 µg/m3 increment: 1.09, 95%CI: 1.01-1.17); PM2.5 (OR: 1.05, 95%CI: 1.03-1.07), SO2 (OR: 1.15, 95%CI: 1.08-1.22), and NO2 (OR: 1.05, 95%CI: 1.03-1.07) were positively associated with neurodevelopmental retardation. Such associations appeared stronger for exposures over the first and second trimesters. No significant associations were detected for weight growth. CONCLUSIONS: Maternal exposure to air pollution during pregnancy was associated with higher risks of impairments in both physical growth, particularly body length, and neurodevelopment.

Associations of COVID-19 lockdown with gestational length and preterm birth in China.

BACKGROUND: The effects of COVID-19 lockdown measures on maternal and fetal health remain unclear. We examined the associations of COVID-19 lockdown with gestational length and preterm birth (PTB) in a Chinese population. METHODS: We obtained medical records of 595,396 singleton live infants born between 2015 and 2020 in 5 cities in Guangdong Province, South China. The exposed group (N = 101,900) included women who experienced the COVID-19 Level I lockdown (1/23-2/24/2020) during pregnancy, while the unexposed group (N = 493,496) included women who were pregnant during the same calendar months in 2015-2019. Cumulative exposure was calculated based on days exposed to different levels of emergency responses with different weighting. Generalized linear regression models were applied to estimate the associations of lockdown exposure with gestational length and risk of PTB (< 37 weeks). RESULTS: The exposed group had a shorter mean gestational length than the unexposed group (38.66 vs 38.74 weeks: adjusted ß = - 0.06 week [95%CI, - 0.07, - 0.05 week]). The exposed group also had a higher risk of PTB (5.7% vs 5.3%; adjusted OR = 1.08 [95%CI, 1.05, 1.11]). These associations seemed to be stronger when exposure occurred before or during the 23rd gestational week (GW) than during or after the 24th GW. Similarly, higher cumulative lockdown exposure was associated with a shorter gestational length and a higher risk of PTB. CONCLUSIONS: The COVID-19 lockdown measures were associated with a slightly shorter gestational length and a moderately higher risk of PTB. Early and middle pregnancy periods may be a more susceptible exposure window.

Ambient air pollution exposure associated with glucose homeostasis during pregnancy and gestational diabetes mellitus.

BACKGROUND: To investigate the effects of air pollution exposure during pregnancy on the indicators of glucose homeostasis and gestational diabetes mellitus (GDM). METHODS: We conducted a birth cohort study in Foshan, China during 2015-2019. Oral glucose tolerance test (OGTT) was administered to each participant during pregnancy. GDM was defined according to the International Association of Diabetes and Pregnancy Study Groups criteria (IADPSG). Air pollutant (fine particulate matter (PM2.5), particulate matter with an aerodynamic diameter of 10 µm or less (PM10), sulfate dioxide (SO2), nitrogen dioxide (NO2) and ozone (O3)) concentrations from the air monitoring stations in Foshan were used to estimate individual air pollutant exposure during the first two trimesters. Linear and logistic regression models were employed to estimate the associations between air pollution exposure during the first two trimesters and OGTT glucose levels and GDM. RESULTS: Of 12,842 pregnant women, 3055 (23.8%) had GDM. A 10 µg/m3 increase in PM2.5, PM10 and SO2 during trimester 1, trimester 2 and two trimesters were associated with 0.07 mmol/L to 0.29 mmol/L increment in OGTT-fasting glucose levels in single-pollutant model. A 10 µg/m3 increase in NO2 and O3 during two trimesters were associated with 0.15 mmol/L and 0.12 mmol/L decrease in OGTT-fasting glucose in single-pollutant model. However, no significant or weaker effects of O3 during two trimesters on OGTT-fasting glucose were observed in two-pollutant models. Moreover, exposure to PM2.5, PM10 and SO2 were associated with increased risk of GDM in both single- and two-pollutant models. CONCLUSIONS: Our study suggests PM2.5, PM10 and SO2 exposure during the first two trimesters might increase the risk of GDM.

Maternal fasting glucose levels throughout the pregnancy and risk of adverse birth outcomes in newborns: a birth cohort study in Foshan city, Southern China.

OBJECTIVE: We aimed to investigate the associations between maternal fasting plasma glucose (FPG) levels and glycemic fluctuations during different trimesters and adverse birth outcomes among newborns. METHODS: This cohort study used data from 63 213 pregnant women and their offspring in Foshan city from November 2015 to January 2019. Associations between maternal FPG and glycemic fluctuations during different trimesters and adverse birth outcomes [congenital heart defect (CHD), macrosomia, small/large for gestational age (SGA/LGA), and preterm birth (PTB)] in newborns were estimated using mixed-effects logistic regression models. RESULTS: A total of 45 516 participants accepted at least one FPG test throughout pregnancy, and 7852 of whom had glycemic trajectory data. In the adjusted model, higher maternal FPG throughout the pregnancy was associated with an increased risk of adverse birth outcomes (except for SGA). Each 1 mmol/L increase in maternal FPG during trimester 1 was associated with higher odds of CHD (OR = 1.14 (95% CI: 1.02, 1.26)). The same increase in maternal FPG during trimester 3 was associated with a higher risk of PTB (OR = 1.05 (95% CI: 1.01, 1.10)). Increment of maternal FPG during trimester 2 and trimester 3 was associated with a higher risk of macrosomia and LGA. Increase in FPG throughout the pregnancy was associated with slightly lower odds of SGA. Similar results were observed when analyzing the associations between glycemic fluctuations during different trimesters and adverse birth outcomes. CONCLUSIONS: Our findings indicate higher maternal FPG levels during different trimesters were associated with different adverse birth outcomes, which suggests the importance of glycemic management throughout the pregnancy.

The Role of Albumin in the Diagnosis of Neonatal Sepsis Over the Last 11 Years: A Retrospective Study.

Background: There are many difficulties and uncertainties in the early diagnosis of neonatal sepsis. The aim of this study was to determine whether albumin (ALB) is useful for the early diagnosis of neonatal sepsis using ALB, C-reactive protein (CRP) and procalcitonin (PCT) together. Methods: ALB, CRP, PCT and white blood cell (WBC) data from 732 patients with neonatal sepsis and 1317 neonatal infection patients hospitalized in Foshan Maternal and Child Health Hospital from 2011 to 2022 were collected. Receiver operating characteristic (ROC) and logistic regression analyses were performed to assess the diagnostic value of ALB, CRP, PCT and the WBC count for neonatal sepsis. The roles of ALB, CRP, PCT and the WBC count in the diagnosis of neonatal sepsis were analysed by using subject working characteristics (ROC) and areas under the curve (AUCs), and the variables were combined to determine which combination had the best diagnostic efficacy. Results: In the sepsis group, the ALB, CRP, and PCT levels and the WBC count were significantly higher than those in the infection group (P<0.001). In all infants, the sensitivities and specificities of ALB, CRP, PCT, and WBC count were 0.411, 0.596, 0.483 and 0.411, respectively, and 0.833, 0.846, 0.901 and 0.796, respectively. With a sensitivity of 0.646, a specificity of 0.929, and an AUC of 0.834, the best combination was that of ALB, CRP, and PCT, which was better than that of CRP + PCT, CRP + ALB and PCT + ALB. Conclusion: In neonatal sepsis, in the absence of blood culture results, the combination of ALB, CRP, and PCT is more reliable than CRP, PCT, or CRP+PCT alone. These results suggest that ALB is a useful inflammatory biomarker for the early diagnosis of neonatal sepsis, and can improve the diagnostic efficiency.

4-[(3-Meth-oxy-anilino)methyl-idene]-2-phenyl-1,3-oxazol-5(4H)-one.

In the title compound, C(17)H(14)N(2)O(3), the oxazolone ring is essentially planar [maximum deviation = 0.004 (1) Å] and is oriented with respect to the phenyl and benzene rings at 10.06 (9) and 5.63 (8)°, respectively; the dihedral angle between the phenyl ring and the benzene ring is 15.69 (8)°. In the crystal, N-H⋯O hydrogen bonds link the mol-ecules into chains running along the a axis. Neighbouring chains are inter-connected by π-π stacking, the centroid-centroid distance being 3.6201 (9) Å.

Prenatal exposure to air pollution and neurodevelopmental delay in children: A birth cohort study in Foshan, China.

BACKGROUND: Prenatal exposure to air pollution may have adverse effects on neurodevelopment in children, but epidemiological evidence remains inconclusive. OBJECTIVE: To investigate the associations between prenatal air pollution exposure and neurodevelopmental delay. METHODS: We conducted a birth cohort study based on pregnancy and birth registry in Foshan, China. Exposure to particulate matter of aerodynamic diameter < 1 µm, 2.5 µm, 10 µm (PM1, PM2.5, PM10), nitrogen dioxide (NO2) and sulfur dioxide (SO2) over pregnancy (trimester 1, 2, 3 and entire pregnancy) was estimated at each woman's residential address using spatial-temporal models. Neurodevelopmental assessment was performed by pediatricians using a five-domain scale and developmental quotient (DQ) was calculated as a global measure. Logistic regression models were used to investigate the associations between prenatal air pollution exposure and neurodevelopmental delay (DQ < 75) with adjustment for potential confounders. RESULTS: We included 15,778 child-mother pairs in this analysis, including 1013 children with neurodevelopmental delay. We observed positive associations between prenatal exposure to air pollution and higher risk of neurodevelopmental delay in children. The adjusted odds ratios (ORs) per 10 µg/m3 elevation in PM1, PM2.5, PM10, NO2 and SO2 in entire pregnancy were 1.12 [95% confidence interval (CI): 1.01, 1.25], 1.15 (95% CI: 1.03, 1.29), 1.12 (95% CI: 1.02, 1.24), 1.06 (95% CI: 0.94, 1.19) and 1.58 (95% CI: 1.11, 2.23), respectively. The associations were more robust for trimester 1 and trimester 2, especially trimester 1. CONCLUSIONS: Exposure to air pollution during pregnancy, especially early-to-mid pregnancy, was associated with increased risk of neurodevelopmental delay in young children, indicating its adverse neurodevelopmental effects in early-life stage.

Association of COVID-19 Lockdown With Gestational Diabetes Mellitus.

Importance: The ongoing pandemic of COVID-19 is still affecting our life, but the effects of lockdown measures on gestational diabetes mellitus (GDM) in pregnant women remain unclear. Aim: To investigate the association between COVID-19 lockdown and GDM. Subjects and Methods: Medical records of 140844 pregnant women during 2015-2020 were extracted from 5 hospitals in Guangdong Province, China. Pregnant women who underwent the COVID-19 Level I lockdown (1/23 - 2/24/2020) during pregnancy were defined as the exposed group (N=20472) and pregnant women who underwent the same calendar months during 2015-2019 (1/23 - 2/24) were defined as the unexposed group (N=120372). Subgroup analyses were used to explore the potential susceptible exposure window of COVID-19 lockdown on GDM. Cumulative exposure is quantitatively estimated by assigning different weights to response periods with different exposure intensities. A logistic regression model was used to estimate the association between COVID-19 lockdown exposure and GDM. Results: The rates of GDM in the exposed and unexposed groups were 15.2% and 12.4%, respectively. The overall analyses showed positive associations (odds ratio, OR=1.22, 95%CI: 1.17, 1.27) between lockdown exposure and GDM risk in all pregnant women. More pronounced associations were found in women who underwent the COVID-19 lockdown in their first four months of pregnancy, and the adjusted OR values ranged from 1.24 (95%CI: 1.10, 1.39) in women with 5-8 gestational weeks (GWs) to 1.35 (95%CI: 1.20, 1.52) with < 5 GWs. In addition, we found a positive exposure-response association of cumulative lockdown exposure with the risk of GDM. Conclusions: The COVID-19 lockdown was associated with an increased risk of GDM, and the first four months of pregnancy may be the window for sensitive exposure.

Nuciferine administration in C57BL/6J mice with gestational diabetes mellitus induced by a high-fat diet: the improvement of glycolipid disorders and intestinal dysbacteriosis.

Gestational diabetes mellitus (GDM) has become a global health concern as the main result of its contribution to the high risk of adverse pregnancy outcomes for both the mother and fetus. However, there is absence of an ideal and widely acceptable therapy. Nuciferine has previously been shown to exert beneficial effects in various metabolic diseases. This study aimed to investigate the potential therapeutic efficacy of nuciferine on GDM in C57BL/6J mice induced by a high-fat diet (HFD), which has not been reported before. The results showed that nuciferine improved glucose intolerance, reduced lipid accumulation and increased the glycogen content within hepatocytes, and decreased placental lipid and glycogen deposition, thus ameliorating glycolipid disorders in GDM mice. Additionally, nuciferine protected against histological degeneration of metabolism-associated critical organs including the liver, pancreas, and abdominal adipose tissue. Most interestingly, nuciferine could correct intestinal dysbacteriosis in GDM mice, as evidenced by the elevation of probiotic abundances consisting of Akkermansia, Lactobacillus, and Bifidobacterium, which were all negatively correlated with serum and liver triglyceride (TG) and positively associated with hepatic glycogen, and the reduction of conditional pathogen abundances including Escherichia-Shigella and Staphylococcus, and the latter was positively related to serum and liver TG and negatively linked with liver glycogen. Collectively, these findings suggest that nuciferine as a food-borne strategy played important roles in the management of GDM.

MiR-139-5p has an antidepressant-like effect by targeting phosphodiesterase 4D to activate the cAMP/PKA/CREB signaling pathway.

BACKGROUND: Phosphodiesterase 4D (PDE4D) inhibitor is commonly used to treat depression, but side effects seriously decrease its efficacy. PDE4D was a downstream target mRNA of miR-139-5p. Therefore, we examined the effects of hippocampal miR-139-5p gain- and loss-of-function on depression-like behaviors, the expression level of PDE4D, and hippocampus neurogenesis. METHODS: Bioinformatic analyses were carried out to to screen differential genes. Quantitative real-time polymerase chain reaction (qRT-PCR) and luciferase reporter assay were used to confirm the relationship between miR-139-5p and PDE4D. MiR-139-5p mimics, miR-139-5p inhibitor, or miR-NC were used to explore the function of miR-139-5p in HT-22 cells. We further explored the role of miR-139-5p in vivo using AAV-injection. Elisa, western blotting, and fluorescence in situ hybridization (FISH) were used to detect the expression of miR-139-5p and PDE4D in CRC tissues. RESULTS: Here, we showed that PDE4D messenger RNA (mRNA) was a direct target of microRNA (miR)-139-5p, which was downregulated in a chronic ultra-mild stress (CUMS)-induced depression mouse model. Moreover, in experiments in vitro, miR-139-5p mimic repressed PDE4D expression in HT-22 cells, but promoted phosphorylated cyclic-AMP response element-binding protein (p-CREB) and brain-derived neurotrophic factor (BDNF) expression. Interestingly, adeno-associated virus (AAV)-miR-139-5p downregulated susceptibility to stress-induced depression-like behaviors in mice. AAV-miR-139-5p suppressed PDE4D in mouse hippocampal cells, increasing expression level of cyclic adenosine monophosphate (cAMP), p-CREB, and BDNF, and stimulating mouse hippocampal neurogenesis. CONCLUSIONS: Our findings suggested that miR-139-5p acted like an antidepressant by targeting PDE4D, thereby regulating the cAMP/protein kinase A (PKA)/CREB/BDNF pathway to improve depression.

Assessment of the bioaccessibility of polycyclic aromatic hydrocarbons in topsoils from different urban functional areas using an in vitro gastrointestinal test.

Profiles of the bioaccessibility of soil polycyclic aromatic hydrocarbons (PAHs) in different urban functional areas of Xiamen City, Fujian, China were investigated. A physiologically based in vitro test was used to evaluate the bioaccessibility of total and individual PAHs. There was no obvious correlation between total concentrations of PAHs and bioaccessibility during the gastrointestinal phase for the soils from different functional areas. Results showed that the bioaccessibility variation in the gastrointestinal phase (ranging from 14.6% to 63.2%) was significantly higher than that in the gastric phase (ranging from 4.9% to 21.8%). The bioaccessibility in the gastrointestinal phase was not only determined by soil organic materials but also directly related to physical and chemical properties of individual PAHs, except for two-ring PAHs. Increasing soil organic material content or decreasing ring numbers of PAHs could result in the decrease of PAH bioaccessibility. The total PAH bioaccessibility was largely contributed by individual PAHs with relatively high molecular weight.

Maternal air pollution exposure associated with risk of congenital heart defect in pre-pregnancy overweighted women.

OBJECTIVES: Prenatal exposure to air pollutant has been associated with congenital heart defect (CHD). However, no study has investigated this effect in pre-pregnancy overweighted women. This study aimed to evaluate gestational exposure to particulate pollutant (PM2.5) and gaseous air pollutants (O3 and NO2) on the risk of CHD, and explore the potential effect modifiers including maternal age, pre-pregnancy BMI and pregestational diseases. METHODS: In this birth cohort study, a total of 63,213 pregnant women in Foshan, China were initially recruited and followed from their first hospital visit for pregnancy to delivery during 2015-2019. CHD cases were confirmed by the records in hospital- and population- based birth defect surveillance systems. Air pollutant exposures were estimated by the daily concentrations measured in air monitoring stations in each participant's residential county. Mixed-effects regression models, adjusted for potential confounding factors were applied to estimate the associations between air pollutant and CHD during the first three months of the pregnancy. RESULTS: A total of 985 (1.6%) newborns were identified as CHD cases. For each 10 µg/m3 increase in ambient O3 during the 1st month, the OR values for CHD were 1.03 (95% CI: 0.94, 1.13) in pre-pregnancy normal weighted women and 1.24 (95% CI: 1.01, 1.53) in pre-pregnancy overweighted women. For each 10 µg/m3 increase in NO2 during the 3rd month, the OR values for CHD were 1.09 (95% CI: 1.01, 1.18) in pre-pregnancy normal weighted women and 1.27 (95% CI: 1.07, 1.51) in pre-pregnancy overweighted women. No significant associations were found between PM2.5 exposure and CHD in our analysis. CONCLUSIONS: This study demonstrates that gaseous air pollutants (O3 and NO2) exposure during the cardiac embryogenesis period is associated with an increased risk of CHD, particularly for pre-pregnancy overweighted women.

The mediation effect of maternal glucose on the association between ambient air pollution and birth weight in Foshan, China.

Maternal blood glucose level is associated with fetal growth, therefore, its role in the associations between air pollution and birth weight deserves investigation. We examined the mediation effect of maternal blood glucose on the associations between maternal air pollution exposure and birth weight. A total of 10,904 pregnant women in Foshan, China during 2015-2019 were recruited. Oral glucose tolerance test (OGTT) was administered to each participant after late trimester 2. Air pollution data at the monitoring stations in residential districts was used to estimate exposures of each participant during trimester 1 and trimester 2. Mixed-effects linear models were used to estimate the associations between air pollution and birth weight. After controlling for ten covariates, the direct effect of PM2.5 and SO2 (each 10 µg/m3 increment) on birth weight was -15.7 g (95% CI: -29.4, -4.8 g) and -83.6 g (95% CI: -134.8, -33.0 g) during trimester 1. The indirect effect of PM2.5 and SO2 (each 10 µg/m3 increment) on birth weight by increasing maternal fasting glucose level was 6.6 g (95% CI: 4.6, 9.1 g) and 22.0 g (95% CI: 4.1, 44.0 g) during trimester 1. Our findings suggest that air pollution might affect the birth weight through direct and indirect pathway, and the indirect effect might be mediated by maternal blood glucose.

Removal of metal catalyst in multi-walled carbon nanotubes with combination of air and hydrogen annealing followed by acid treatment.

Multi-walled carbon nanotubes (MWCNTs) prepared by the decomposition of CH4 on a Ni-MgO catalyst were treated with air and hydrogen annealing, and the combination of air and hydrogen annealing, respectively, followed by acid reflux. The treated MWCNTs were characterized by the techniques of transmission electron microscopy, thermogravimetric analysis and flame atomic absorption spectrometry. The results showed that hydrogen annealed MWCNTs were more air stable than air annealed ones. Followed by acid treatment, the combination of air and hydrogen annealing was more efficient than either air annealing or hydrogen annealing for the removal of catalyst in MWCNTs. For the treatment with 2 h of hydrogen annealing followed by 2 h of air annealing, the catalyst Ni remained in the purified sample was 10.8 microg/g, and the yield rate was 82.3%. With 2 h of air annealing followed by 2 h of hydrogen annealing, the data were 5.8 microg/g and 61.9%, respectively. The different functions of air and hydrogen during annealing were discussed.

Accumulation and biodegradation of phenanthrene and fluoranthene by the algae enriched from a mangrove aquatic ecosystem.

This study focused on the accumulation and biodegradation of two typical polycyclic aromatic hydrocarbons (PAHs), phenanthrene (PHE) and fluoranthene (FLA), by the diatoms enriched from a mangrove aquatic ecosystem in the Jiulong River estuary, China. After separation, purification and culture, Skeletonema costatum (Greville) Cleve and Nitzschia sp. were exposed to different concentrations of PHE, FLA, and a mixture of the two. The results showed that the tolerance of S.costatum to PHE and FLA was greater than that of Nitzschia sp., and that the toxic effect of FLA on S. costatum and Nitzschia sp. was higher than that of PHE. The microalgal species S. costatum and Nitzschia sp. were capable of accumulating and degrading the two typical PAHs simultaneously. The accumulation and degradation abilities of Nitzschia sp. were higher than those of S. costatum. Degradation of FLA by the two algal species was slower, indicating that FLA was a more recalcitrant PAH compound. The microalgal species also showed comparable or higher efficiency in the removal of the PHE-FLA mixture than PHE or FLA singly, suggesting that the presence of one PAH stimulated the degradation of the other.

Cosynthesis of l-homophenylalanine and 2-phenylethanol by recombinant Saccharomyces cerevisiae expressing aspartate aminotransferase from Escherichia coli BL21(DE3).

The Escherichia coli aspartate aminotransferase gene was introduced into a high 2-phenylethanol (2-PEA) producing Saccharomyces cerevisiae YS58, and the recombinant strain of S. cerevisiae was utilized for the co-production of 2-PEA and l-homophenylalanine (L-HPA) via a fermentation process. The L-HPA productivity of the recombinant S. cerevisiae improved 78.9% in comparison to the wild-type S. cerevisiae. High yields of 43.7 mM L-HPA and 32.4 mM 2-PEA were achieved. As a result, the coupling of the biosynthesis process for these two products in the recombinant strain led to a more complete and efficient utilization of the substrate, l-phenylalanine.

Prenatal Exposure to Environmental Tobacco Smoke and Hyperactivity Behavior in Chinese Young Children.

This study aimed to examine the association between prenatal environmental tobacco smoke (ETS) exposure and hyperactivity behaviors in young children. A cross-sectional study was undertaken among 21,243 participants from all of the kindergartens in Longhua District of Shenzhen, China. Multivariate logistic regression models and hierarchical linear models were employed to assess the associations. After adjusting for potential confounders of gender, preterm birth, birth asphyxiation, etc., prenatal ETS exposure was significantly associated with an increased risk of hyperactivity behaviors in young children (OR (95% CI) = 1.51 (1.28-1.77); ß (95% CI) = 0.017 (0.013-0.020)). Along with increases in children's prenatal ETS exposure dose (measured by daily ETS exposure duration, daily cigarette consumption by household members, and overall score of prenatal ETS exposure), the children were also increasingly more likely to exhibit hyperactivity behaviors. Furthermore, children whose mothers had prenatal ETS exposure in any one or more of the pregnancy trimesters were more likely to exhibit hyperactivity behaviors as compared with those born to non-exposure mothers (all p < 0.05). Overall, prenatal ETS exposure could be associated with a detrimental impact on offspring's hyperactivity behaviors, and public health efforts are needed to reduce prenatal ETS exposure.

Acute toxicity profile of cadmium revealed by proteomics in brain tissue of Paralichthys olivaceus: potential role of transferrin in cadmium toxicity.

An analytical approach using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) separated proteins from the brain tissue of the fish Paralichthys olivaceus. Approximately 600 protein spots were detected from the brain sample when applying 600 microg protein to a 2D-PAGE gel in the pH range 3.5-10.0. Compared to a control sample, significant changes of 24 protein spots were observed in the fish tissue exposed to acute toxicity of seawater cadmium (SCAT) at 10 ppm for 24h. Among these spots, nine were down-regulated, nine were up-regulated, two showed high expression, and four showed low expression. The collected spots were identified by peptide mass fingerprinting (PMF) and database search, and they were further classified by LOC tree, a hierarchical system of support vector machines which predict their sub-cellular localization. The amount of transferrin expression in brain cells decreased linearly with the increase of SCAT concentration in seawater. Among the 24 proteins identified on a 2D-PAGE gel, 9 demonstrated a synchronous response to acute cadmium, suggesting that they might represent a biomarker profile. Based on their variable levels and trends on the 2D-PAGE gel this protein (likely to be transferrin) suggesting they might be utilized as biomarkers to investigate cadmium pollution levels in seawater and halobios survival, as well as to evaluate the degree of risk of human fatalities. The results indicate that the application of multiple biomarkers has an advantage over a single biomarker for monitoring levels of environmental contamination.

Effect of pH and phosphate on trapping capacity of various heavy metal ions with ferritin reactor in flowing seawater.

We describe a protein reactor consisting of native liver ferritin of Dasyatis akajei (DALF) and a dialysis bag. Our goal was to study a ferritin reactor for its capacity to trap various heavy metal ions (M2+) in flowing seawater. The reactor is sensitive and inexpensive and can be operated by nonprofessional technicians. A positive relationship between the number of trapped M2+ with the DALF reactor and its concentration in the flowing seawater was observed. Both the pH in the medium and the phosphate content within the ferritin cavity strongly affected trapping capacity. It was found that the ferritin released its phosphate compound directly with a shift in pH without the need for releasing reagent, which differs from the phosphate release characteristics of horse spleen ferritin, as previously described. This behavior evidently makes the trapping capacity with the ferritin reactor weaken, indicating that this trapping capacity is tightly connected to its phosphate compound. Our study shows that a self-regulation ability of the ferritin shell rather than its phosphate compound plays an important role in controlling the rate and capacity of trapping M2+. The ferritin reactor was constructed to monitor the contamination level of M2+ in flowing seawater. Our preliminary data along with fieldwork indicate that the DALF reactor is an analytical means for effectively monitoring the contamination level of M2+ in flowing seawater.