Four-band terahertz metamaterial absorber based on Dirac semimetal for a refractive index sensing application.

We design a four-band narrow-band near-perfect absorber based on bulk Dirac semimetal (BDS) metamaterial in the terahertz region. The absorber has a top-to-bottom three-layer structure of a BDS layer, an insulating dielectric slab, and a gold layer. The BDS is flexible and tunable, allowing the Fermi energy level to be adjusted by changing the applied bias voltage, thus changing the absorption characteristics of the absorber. We use the time-domain finite-difference method to simulate the absorption characteristics of the absorber, which could achieve four discrete near-perfect absorption peaks at 0.98 THz, 1.70 THz, 2.02 THz, and 2.36 THz. The absorber is polarization sensitive, and the conversion between four-band absorption and three-band absorption is achieved by changing the incident polarization angle. We also change the structure of the absorber to study the absorption characteristics and break the structural symmetry to achieve a larger number of absorption peaks. Besides, the sensing performance of four-band narrow-band absorption is analyzed, and the maximum sensitivity of the absorber is 112.78 GHz/RIU. The device should have vast application prospects for bio-detection and high-sensitivity biosensing detection.

Inhibitory Effects of Extracellular Vesicles from iPS-Cell-Derived Mesenchymal Stem Cells on the Onset of Sialadenitis in Sjögren's Syndrome Are Mediated by Immunomodulatory Splenocytes and Improved by Inhibiting miR-125b.

Extracellular vesicles (EVs) from allogeneic-tissue-derived mesenchymal stem cells (MSCs) are promising to improve Sjögren's syndrome (SS) treatment, but their application is hindered by high variations in and limited expandability of tissue MSCs. We derived standardized and scalable MSCs from iPS cells (iMSCs) and reported that EVs from young but not aging iMSCs (iEVs) inhibited sialadenitis onset in SS mouse models. Here, we aim to determine cellular mechanisms and optimization approaches of SS-inhibitory effects of iEVs. In NOD.B10.H2b mice at the pre-disease stage of SS, we examined the biodistribution and recipient cells of iEVs with imaging, flow cytometry, and qRT-PCR. Intravenously infused iEVs accumulated in the spleen but not salivary glands or cervical lymph nodes and were mainly taken up by macrophages. In the spleen, young but not aging iEVs increased M2 macrophages, decreased Th17 cells, and changed expression of related immunomodulatory molecules. Loading miR-125b inhibitors into aging iEVs significantly improved their effects on repressing sialadenitis onset and regulating immunomodulatory splenocytes. These data indicated that young but not aging iEVs suppress SS onset by regulating immunomodulatory splenocytes, and inhibiting miR-125b in aging iEVs restores such effects, which is promising to maximize production of effective iEVs from highly expanded iMSCs for future clinical application.

PM2.5 exposure increases the risk of preterm birth in pre-pregnancy impaired fasting glucose women: A cohort study in a Southern province of China.

Previous studies have indicated maternal exposure to particles with aerodynamic diameter <2.5 µm (PM2.5) is associated with preterm birth (PTB). However, no study has investigated this effect in pre-pregnancy impaired fasting glucose (IFG) women. This study aimed to differentiate the effects of maternal PM2.5 exposure on PTB between pre-pregnancy IFG and normoglycemia women, and to further identify the susceptible window. This cohort study was conducted between January 2014 and December 2017 in 21 Chinese cities. All the recruited women received pre-pregnancy fasting serum glucose (FSG) tests and were followed up for their delivery outcomes. The PM2.5 exposures were estimated by the daily air pollution concentrations of the nearby monitors. Women with FSG below 7.0 mmol/L were included in the analysis. We employed the Cox proportional hazards models to examine whether PM2.5 exposure was associated with PTB. 237957 women were included and 7055 (3.0%) of them were pre-pregnancy IFG. During the entire pregnancy, we found 24.1% (HR = 1.241; 95% CI: 1.069, 1.439), 61.8% (HR = 1.618; 95% CI: 1.311, 1.997) and 18.6% (HR = 1.186; 95% CI: 1.004, 1.402) of increases in risk for all PTB, early PTB (20-33 gestational weeks) and late PTB (34-36 gestational weeks) among the pre-pregnancy IFG women, and 15.9% (HR = 1.159; 95% CI: 1.127, 1.192), 33.9% (HR = 1.339; 95% CI: 1.255, 1.430) and 13.2% (HR = 1.132; 95% CI: 1.098, 1.168) of increases in risk for all PTB, early PTB and late PTB among the normoglycemia women, with each 10 µg/m3 increment of PM2.5 exposure, respectively. Furthermore, PM2.5 exposure had the strongest effect on all PTB during trimester 1 (0-12 gestational weeks) among the pre-pregnancy IFG women, compared with the less strong effect during trimester 1 among the normoglycemia women. In conclusion, pre-pregnancy IFG increases the risk of PTB attributed to PM2.5, especially during trimester 1. Moreover, the effects of PM2.5 are greater on early PTB than late PTB for both pre-pregnancy IFG and normoglycemia women.

Same environment, stratified impacts? Air pollution, extreme temperatures, and birth weight in South China.

This paper investigates whether associations between birth weights and prenatal ambient environmental conditions-pollution and extreme temperatures-differ by 1) maternal education; 2) children's innate health; and 3) interactions between these two. We link birth records from Guangzhou, China, during a period of high pollution, to ambient air pollution (PM10 and a composite measure) and extreme temperature data. We first use mean regressions to test whether, overall, maternal education is an "effect modifier" in the relationships between ambient air pollution, extreme temperature, and birth weight. We then use conditional quantile regressions to test for effect heterogeneity according to the unobserved innate vulnerability of babies after conditioning on other confounders. Results show that 1) the negative association between ambient exposures and birth weight is twice as large at lower conditional quantiles of birth weights as at the median; 2) the protection associated with college-educated mothers with respect to pollution and extreme heat is heterogeneous and potentially substantial: between 0.02 and 0.34 standard deviations of birth weights, depending on the conditional quantiles; 3) this protection is amplified under more extreme ambient conditions and for infants with greater unobserved innate vulnerabilities.

Temperature variation and preterm birth among live singleton deliveries in Shenzhen, China: A time-to-event analysis.

OBJECTIVE: Ambient temperature extremes due to heat exposure was an established risk factor for preterm birth (<37 gestational weeks). However, there is insufficient epidemiological evidence on the effects of temperature variation(TV), although TV is also associated with heat exposure and can influence human health risk. This study aimed to investigate the relationship between inter- and intraday TV and preterm birth (PTB). METHOD: A total of 1,388,994 live singleton births were collected from January 2003 to December 2012, from the Shenzhen Birth registry system. Daily temperature range (DTR) was defined as the difference between the highest and lowest recorded daily temperature. Intraday TV was defined as the maximum daily diurnal temperature range in a given week (Max-DTR). Inter-day TV was defined as the maximum increase or decrease in daily mean temperature between days t and t-1in a given week; either an increase (Temp-inc) or a decrease (Temp-dec). We used Cox proportional hazards models to estimate TV-related PTB risks during the first trimester, the second trimester, and in late pregnancy. RESULTS: The maximum values for DTR, Temp-inc, and Temp-dec were 17 °C, 8 °C and 11 °C, respectively. The greatest TV-related PTB risk occurred in the second trimester, with 5.8% (95%CI: 3.3%, 8.3%), 23.7% (95%CI: 19.6%, 27.9%), and 4.4% (95%CI: 1.8%, 7.1%) differences per 1 °C increase in Max-DTR, Temp-inc, and Temp-dec, respectively. Greater TV was associated with elevated PTB risk during the warm season. The association between TV and PTB was modified by seasons, maternal education and chronic conditions. CONCLUSIONS: Sharp TV is a likely risk factor for PTB. Policy makers and clinicians should recognize the potential role of TV in the etiology of PTB so that interventions can be designed to protect pregnant women and their fetuses against extreme temperatures.

The impact of maternal prepregnancy impaired fasting glucose on preterm birth and large for gestational age: a large population-based cohort study.

BACKGROUND: The impact of maternal prepregnancy impaired fasting glucose on preterm birth and large for gestational age has been poorly understood. OBJECTIVES: We aimed to estimate the impact of prepregnancy impaired fasting glucose defined by the World Health Organization cut point on the risk of preterm birth and large for gestational age and to investigate whether the World Health Organization cut point of impaired fasting glucose was appropriate for identifying women at risk of preterm birth and large for gestational age among the Chinese population. STUDY DESIGN: This was a retrospective cohort study of women from the National Free Preconception Health Examination Project with singleton birth from 121 counties/districts in 21 cities of Guangdong Province, China, from Jan. 1, 2013, to Dec. 31, 2017. Women were included if their prepregnancy fasting glucose was less than 7.0 mmol/L. The primary outcomes were preterm birth (gestational age <37 weeks), early preterm birth (gestational age <34 weeks), large for gestational age (birthweight by gestational age >90th percentile based on the international standards in the International Fetal and Newborn Growth Consortium for the 21st Century study), and severe large for gestational age (birthweight by gestational age >97th percentile). We calculated the adjusted risk ratio for impaired fasting glucose and a 1 standard deviation increase in fasting glucose. RESULTS: We included 640,469 women. Of these, 31,006 (4.84%) met the World Health Organization cut point for impaired fasting glucose, 32,640 (5.10%) had preterm birth and 7201 (1.12%) had early preterm birth, 45,532 (7.11%) had large for gestational age birth, and 16,231 (2.53%) had severe large for gestational age birth. Compared with women with normoglycaemia, women with prepregnancy impaired fasting glucose had a 7.0% higher risk of preterm birth (adjusted risk ratio, 1.07, 95% confidence interval, 1.02-1.12), 10.0% had a higher risk of large for gestational age (adjusted risk ratio, 1.10, 95% confidence interval, 1.06-1.14), and 17.0% had a higher risk of severe large for gestational age (adjusted risk ratio, 1.17, 95% confidence interval, 1.10-1.26). No significant association of prepregnancy impaired fasting glucose with early preterm birth was found. The association of prepregnancy impaired fasting glucose with preterm birth and large for gestational age were similar in subgroups of women with various baseline characteristics. Adjusted risk ratio for preterm birth per standard deviation fasting glucose (0.7 mmol/L) was 0.99 (95% confidence interval, 0.98-1.00), for early preterm birth an adjusted risk ratio of 0.99 (confidence interval, 0.97-1.02), for large for gestational age an adjusted risk ratio of 1.04 (confidence interval, 1.03-1.05), and for severe large for gestational age an adjusted risk ratio of 1.03 (confidence interval, 1.01-1.04). CONCLUSION: Our data suggest that maternal prepregnancy impaired fasting glucose increases the risk of preterm birth, large for gestational age, and severe large for gestational age. Data also suggest that the World Health Organization cut point of impaired fasting glucose is too restrictive, and lower levels of fasting glucose also increase the risk of large for gestational age and severe for severe gestational age in the Chinese population. Further investigation is warranted to determine whether and how counseling and interventions for women with prepregnancy impaired fasting glucose could reduce the risk of preterm birth and large for gestational age.

Sperm quality and ambient air pollution exposure: A retrospective, cohort study in a Southern province of China.

BACKGROUND: Abnormal semen quality is one of the common causes of infertility. The relationship between exposure to air pollutants and semen quality is unclear. OBJECTIVES: To evaluate the impact of ambient air pollutant exposures on semen quality. METHODS: We analyzed 3797 semen samples from Guangdong Human Sperm Bank between May 28, 2018 and March 31, 2019. The inverse distance weighted interpolation method was used to estimate the personal exposures to CO, SO2, NO2, O3, PM10 and PM2.5 during the entire period (0-90 lag days) and key periods (0-9, 10-14, 70-90 lag days) of sperm development. Linear mixed models were used to evaluate the exposure-response relationships between air pollutants and semen quality, including sperm concentration, sperm count and sperm motility, after adjusting for other covariates. The regression coefficients and 95% confidence intervals (CIs) associated with each interquartile range (IQR) increase in pollutant concentrations were estimated for each semen quality parameter. RESULTS: Overall, we observed a significant association of decreased sperm count with the exposure to PM10 (-0.2466; -0.4443, -0.0489) and PM2.5 (-0.2910; -0.5401, -0.0419). Among the sperm quality parameters assessed, sperm count was observed more frequently to be negatively associated with ambient air pollutants (CO, NO2, O3, PM10 and PM2.5), especially for the period during 10-14 lag days. In addition, motility decline was significantly associated with O3 in the late stage of sperm development. Sensitivity analyses for subgroup population yielded similar results. No significant association was found between all pollutants and sperm concentration (all P > 0.05). CONCLUSIONS: Our results indicate that ambient air pollutants exposures during sperm development may have an adverse effect on semen quality, especially for sperm count and motility. The findings emphasize the potential to improve semen quality by reducing ambient air pollutant exposures, and the importance of taking into account the critical period of sperm development when protective measures are implemented.

Biomimetic nanovesicles made from iPS cell-derived mesenchymal stem cells for targeted therapy of triple-negative breast cancer.

Nanoparticles made from membrane of mesenchymal stem cells (MSCs) showed active targeting capacities to prostate and lung cancers, but further studies are hindered by limited expandability and donor variations of tissue-derived MSCs. We have derived MSCs with an unlimited supply and uniform homing capacity to triple-negative breast cancer (TNBC) from human induced pluripotent stem cells (iPSCs). By breaking down intact iPSC-MSCs, we efficiently developed nanovesicles that selectively accumulated in primary and metastatic TNBC after systemic infusion in mouse models. When loaded with a chemotherapeutic drug doxorubicin, iPSC-MSC nanovesicles showed superior cytotoxic effects on doxorubicin-resistant TNBC cells, and significantly decreased the incidence and burden of metastases in mouse models of spontaneous and experimental metastatic TNBC compared with free or liposomal doxorubicin. These nanovesicles showed no detectable immunogenicity or toxicity, and are stable after storage. Our data indicate that iPSC-MSC nanovesicles are promising to improve TNBC treatment as a standardized targeting platform.

Interaction of Air Pollutants and Meteorological Factors on Birth Weight in Shenzhen, China.

BACKGROUND: This study aimed to assess if air pollutants and meteorological factors synergistically affect birth outcomes in Shenzhen, China. METHODS: A total of 1,206,158 singleton live births between 2005 and 2012 were identified from a birth registry database. Daily average measurements of particulate matter ≤10 µm (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), ambient air temperature (T), and dew point temperature (Td), a marker of humidity, were collected. Multivariable logistic regression models were used to evaluate associations between air pollution and small for gestational age (SGA), and full-term low birth weight (TLBW). We classified births into those conceived in the warm (May-October) and cold seasons (November-April) and then estimated interactions between air pollutants and meteorological factors. RESULTS: An interquartile range (IQR) increase in PM10 exposure during the first trimester (23.1 µg/m) and NO2 during both the first and second trimesters (15.1 and 13.4 µg/m) was associated with SGA and TLBW risk; odds ratios ranged from 1.01 (95% confidence interval [CI] = 1.00, 1.02) to 1.09 (1.07, 1.12). We observed interactive effects of both air temperature and humidity on PM10 and SGA for newborns conceived in the warm season. Each IQR increase in PM10 (11.1 µg/m) increased SGA risk by 90% (95% CI = 19%, 205%), 29% (23, 34%), 61% (10, 38%), and 26% (21, 32%) when T < 5th percentile, 5th < T < 95th percentile, Td < 5th percentile, and 5th < Td < 95th percentile, respectively. CONCLUSIONS: Our study found evidence of an interactive effect of air temperature and humidity on the relationship between PM10 exposure and SGA among newborns conceived in the warm season (May-October). Relatively low air temperature or humidity exacerbated the effects of PM10.

MSCs derived from iPSCs with a modified protocol are tumor-tropic but have much less potential to promote tumors than bone marrow MSCs.

Mesenchymal stem or stromal cells (MSCs) have many potential therapeutic applications including therapies for cancers and tissue damages caused by cancers or radical cancer treatments. However, tissue-derived MSCs such as bone marrow MSCs (BM-MSCs) may promote cancer progression and have considerable donor variations and limited expandability. These issues hinder the potential applications of MSCs, especially those in cancer patients. To circumvent these issues, we derived MSCs from transgene-free human induced pluripotent stem cells (iPSCs) efficiently with a modified protocol that eliminated the need of flow cytometric sorting. Our iPSC-derived MSCs were readily expandable, but still underwent senescence after prolonged culture and did not form teratomas. These iPSC-derived MSCs homed to cancers with efficiencies similar to BM-MSCs but were much less prone than BM-MSCs to promote the epithelial-mesenchymal transition, invasion, stemness, and growth of cancer cells. The observations were probably explained by the much lower expression of receptors for interleukin-1 and TGFß, downstream protumor factors, and hyaluronan and its cofactor TSG6, which all contribute to the protumor effects of BM-MSCs. The data suggest that iPSC-derived MSCs prepared with the modified protocol are a safer and better alternative to BM-MSCs for therapeutic applications in cancer patients. The protocol is scalable and can be used to prepare the large number of cells required for "off-the-shelf" therapies and bioengineering applications.

Temporal trends of preterm birth in Shenzhen, China: a retrospective study.

BACKGROUND: Preterm birth is the leading cause of child mortality under 5 years of age. Temporal trends in preterm birth rates are highly heterogeneous among countries and little information exists for China. To address this data gap, we investigated annual changes in preterm birth incidence rate and explored potential determinants of these changes in Shenzhen, China. METHODS: A total of 1.4 million live births, during 2003-2012, were included from the Shenzhen birth registry. Negative-binominal regression models were used to estimate the annual percent changes in incidence. To identify the potential determinants behind temporal trends, we estimated the contribution of each changing risk factor to changes in rate by calculating the difference in population-attributable risk fraction. RESULTS: Annual preterm birth incidence rates increased by 0.94% (95% CI 0.30%, 1.58%) overall, 3.60% (95% CI 2.73%, 4.48%) for medically induced, and 3.13% (95% CI 1.01%, 5.31%) for preterm premature rupture of membranes, but decreased by 2.34% (95% CI 1.62%, 3.06%) for spontaneous preterm labor. Higher maternal educational attainment (0.20 rate increase), lower proportion of inadequate prenatal care (0.15 rate reduction), more multipara (0.08 rate reduction), decreased proportion of preeclampsia or eclampsia (0.05 rate reduction), and larger proportion of young and older pregnant women (0.04 rate increase) were significant contributors to the overall change over time. Contributions of changing risk factors were different between preterm birth subtypes. CONCLUSIONS: Preterm birth rate in Shenzhen, China increased overall during 2003-2012, although trends varied across three preterm birth subtypes. The rising rates were associated with changes in maternal education and age.

miR-34a Targets HDAC1-Regulated H3K9 Acetylation on Lipid Accumulation Induced by Homocysteine in Foam Cells.

Hyperhomocysteinemia (HHcy) promotes atherogenesis by modification of histone acetylation patterns and regulation of miRNA expression while the underlying molecular mechanisms are not well known. In this study, we investigated the effects of homocysteine (Hcy) on the expression of histone deacetylase 1 (HDAC1) and tested our hypothesis that Hcy-induced atherosclerosis is mediated by increased HDAC1 expression, which is regulated by miR-34a. The expression of HDAC1 increased and acetylation of histone H3 at lysine 9 (H3K9ac) decreased in the aorta of ApoE-/- mice fed with high methionine diet, whereas miR-34a expression was inhibited. Over-expression of HDAC1 inhibited H3K9ac level and promoted the accumulation of total cholesterol, free cholesterol, and triglycerides in the foam cells. Furthermore, up-regulation of miR-34a reduced HDAC1 expression and inhibited the accumulation of total cholesterol (TC), free cholesterol (FC), and triglycerides (TG) in the foam cells. These data suggest that HDAC1-related H3K9ac plays a key role in Hcy-mediated lipid metabolism disorders, and that miR-34a may be a novel therapeutic target in Hcy-related atherosclerosis. J. Cell. Biochem. 118: 4617-4627, 2017. © 2017 Wiley Periodicals, Inc.

The association between ambient temperature and preterm birth in Shenzhen, China: a distributed lag non-linear time series analysis.

BACKGROUND: A few studies have examined the association between ambient temperature and preterm birth (PTB), and the results have been inconsistent. This study explored the association between ambient temperature and PTB in Shenzhen, China. METHODS: Data of daily singleton PTB, air pollution and meteorological variables from 2005 to 2011 were collected in Shenzhen. A distributed lag non-linear model (DLNM) was used to investigate the association of the low and high temperatures (1st, 5th, 95th, and 99th percentiles) with PTB. RESULTS: The median temperature was 24.5 °C and the 1st, 5th, 95th, and 99th percentiles of daily mean temperatures were 9, 12.5, 29.9 and 30.7 °C, respectively. The prevalence of singleton PTB was 5.61 % in Shenzhen. The association between temperature and PTB was not linear. There was an immediate positive association of low temperature (1st and 5th percentiles) and a negative association of high temperature (95th and 99th percentiles) with PTB. The effect of low temperature 9 °C (1st) on PTB on the current day was stronger than that of 12.5 °C (5th), with a relative risk (RR) of 1.54 (95 % CI: 1.36-1.75) and 1.49 (95 % CI: 1.35-1.63), respectively. The cumulative RR (up to 30 days) of 9 and 12.5 °C was 1.72 (95 % CI: 1.28-2.33) and 1.96 (95 % CI: 1.60-2.39), respectively. The cumulative effects (up to 30 days) of high temperature (95th and 99th percentiles) on PTB were 0.69 (95 % CI: 0.60-0.80) and 0.62 (95 % CI: 0.52-0.74), respectively. The cumulative effect (up to 30 days) of low temperatures on vaginal delivery PTB was lower than that of the cesarean section PTB with an RR of 1.58 (95 % CI: 1.12-2.22) and 1.93 (95 % CI: 1.21-3.08), respectively. CONCLUSIONS: This study suggests that low temperature might be a risk factor, while high temperature might be a protective factor of PTB in Shenzhen.

Serum Metabolomic Profiling in a Rat Model Reveals Protective Function of Paeoniflorin Against ANIT Induced Cholestasis.

Cholestasis is a leading cause of hepatic accumulation of bile acids resulting in liver injury, fibrosis, and liver failure. Paeoniflorin displays bright prospects in liver protective effect. However, its molecular mechanism has not been well-explored. This study was designed to assess the effects and possible mechanisms of paeoniflorin against alpha-naphthylisothiocyanate-induced liver injury. Ultraperformance liquid chromatography coupled with quadrupole time-of-flight combined with principle component analysis and partial least squares discriminant analysis were integrated to obtain differentiating metabolites for the pathways and clarify mechanisms of disease. The results indicated that paeoniflorin could remarkably downregulate serum biochemical indexes and alleviate the histological damage of liver tissue. Different expression of 14 metabolites demonstrated that paeoniflorin mainly regulated the dysfunctions of glycerophospholipid metabolism and primary bile acid biosynthesis. Moreover, several pathways such as arginine and proline metabolism, ether lipid metabolism, and arachidonic acid metabolism were also related to the efficacy. In conclusion, paeoniflorin has indicated favorable pharmacological effect on serum biochemical indexes and pathological observation on cholestatic model. And metabolomics is a promising approach to unraveling hepatoprotective effects by partially regulating the perturbed pathways, which provide insights into mechanisms of cholestasis.

[Preliminary study on effective components of Tripterygium wilfordii for liver toxicity based on spectrum-effect correlation analysis].

In this paper, the spectrum-effect correlation analysis method was used to explore the main effective components of Tripterygium wilfordii for liver toxicity, and provide reference for promoting the quality control of T. wilfordii. Chinese medicine T.wilfordii was taken as the study object, and LC-Q-TOF-MS was used to characterize the chemical components in T. wilfordii samples from different areas, and their main components were initially identified after referring to the literature. With the normal human hepatocytes (LO2 cell line)as the carrier, acetaminophen as positive medicine, and cell inhibition rate as testing index, the simple correlation analysis and multivariate linear correlation analysis methods were used to screen the main components of T. wilfordii for liver toxicity. As a result, 10 kinds of main components were identified, and the spectrum-effect correlation analysis showed that triptolide may be the toxic component, which was consistent with previous results of traditional literature. Meanwhile it was found that tripterine and demethylzeylasteral may greatly contribute to liver toxicity in multivariate linear correlation analysis. T. wilfordii samples of different varieties or different origins showed large difference in quality, and the T. wilfordii from southwest China showed lower liver toxicity, while those from Hunan and Anhui province showed higher liver toxicity. This study will provide data support for further rational use of T. wilfordii and research on its liver toxicity ingredients.

[Comparison of the effect of three ß-thalassemia prenatal screening strategies using in Guangdong province].

OBJECTIVE: To compare the effect of three ß-thalassemia prenatal screening strategies in Guangdong province. METHODS: A total of 13 284 hospital-delivered couples and 13 369 newborns were recruited from 91 hospitals in 21 counties or districts of Guangdong province from June to December 2012. Mean cell volume (MCV), mean corpuscular hemoglobin (MCH) and hemoglobin A2 (Hb A2) were tested for all the couples, and all the couples and newborns were detected by 17 types of ß-globin gene mutations. The effect of three ß-thalassemia prenatal screening strategies were compared as following: (1) MCV/MCH with Hb A2 serial screening (SS): Hb A2 was tested if the woman's MCV < 82 fl and (or) MCH < 27 pg. If the woman's Hb A2 > 3.5, it meant positive. And if the woman was ß-thalassemia carrier and her husband's Hb A2 > 3.5, it meant couple positive. (2) MCV/MCH with Hb A2 parallel screening (PS): if the woman's MCV < 82 fl and (or) MCH < 27 pg and (or) Hb A2 > 3.5 pg, it meant couple positive. And the husband would be tested for ß-globin gene mutations if the woman was ß-thalassemia carrier. (3) MCV/MCH with Hb A2 serial screening for couples (SSC): if one of the couple or both of them had MCV < 82 fl and (or) MCH < 27 pg, the couple would be tested for Hb A2, and if one of the couple got Hb A2 > 3.5, it meant couple positive. RESULTS: (1) For the SS strategy, the sensitivity was 92.69% (583/629); the specificity was 99.87% (12 638/12 655); the positive predictive value was 97.17% (583/600); and the negative predictive value was 99.64% (12 638/12 684). The results of ß-globin gene mutations tested showed that the rate of ß-thalassemia carriers was 4.74% (629/13 284) in the 13 284 pregnant women, and it was 4.29% (570/13 284) in their husbands. (2) The SS strategy detected 27 (0.20%, 27/13 284) ß-thalassemia carrier couples. For the SS strategy detecting ß-thalassemia carrier couples, the missed diagnosis rate was 11.11% (3/27); the sensitivity was 88.89% (24/27); the specificity was 100.00% (27/27); the positive predictive value was 100.00% (24/24); and the negative predictive value was 99.98% (13 257/13 260). (3) When using the SS strategy for 13 369 offsprings, there were 582 ß-thalassemia carriers (4.35%, 582/13369), including 578 (99.31%, 578/582) minor ß-thalassemia, 3 (0.52%, 3/582) intermedia ß-thalassemia and 1 (0.17%, 1/582) major ß-thalassemia. The SS strategy detected 25 fetuses who needed ß-thalassemia prenatal diagnosis. (4) For the PS strategy, the sensitivity was 98.09% (617/629); the specificity was 88.73% (11 229/12 655); the positive predictive value was 30.20% (617/2 043); and the negative predictive value was 99.89% (11 229/11 241). (5) When using the PS strategy for the ß-thalassemia carrier couples, the sensitivity was 100.00% (27/27); the specificity was 95.55% (12 667/13 257); the positive predictive value was 4.38% (27/617); and the negative predictive value was 100.0% (12 667/12 667). (6) The PS strategy detected 28 fetuses who needed ß-thalassemia prenatal diagnosis in 13 369 offsprings. (7) For the SSC strategy, the sensitivity was 93.80% (590/629); the specificity was 95.75% (12 117/12 655); the positive predictive value was 52.30% (590/1 128); and the negative predictive value was 99.68% (12 117/12 156). When the SSC strategy was used for the husbands, the sensitivity was 92.28% (526/570); the specificity was 95.27% (12 112/12 714);the positive predictive value was 46.63% (526/1 128); and the negative predictive value was 99.64% (12 112/12 156). (8) When the SSC strategy was used in ß-thalassemia carrier couples, the sensitivity was 100.00% (27/27); the specificity was 91.69% (12 156/13 257); the positive predictive value was 2.39% (27/1 128); and the negative predictive value was 100.00% (12 156/12 156). (9) The SSC strategy detected 28 fetuses who needed ß-thalassemia prenatal diagnosis. CONCLUSIONS: All the three ß-thalassemia prenatal screening strategies had good effect in clinical practice and public health. While in the high-prone area of ß-thalassemia, MCV/MCH with Hb A2 parallel screening and MCV/MCH with Hb A2 serial screening for couples stratigies were better.

Prevalence of congenital heart defect in Guangdong province, 2008-2012.

BACKGROUND: Congenital heart defect (CHD) is the most common major malformations in infants. Little is known about the main epidemiologic characteristics of CHD prevalence in Guangdong province, China. Our study was undertaken to investigate the time trends in the prevalence of CHD in Guangdong province from 2008 to 2012. METHODS: Data were retrieved from the Guangdong Hospital-Based Birth Defects Monitoring System during 2008-2012. All infants more than 28 weeks of gestation and infants up to 7 days of age in monitoring hospitals were monitored. We used prevalence rate to describe the difference in prevalence of CHD between rural and urban areas. Odds ratio (OR) and 95% confidence interval (CI) for CHD were calculated for the rural and urban areas. The CHD rate was calculated on the basis of birth defects per 10,000 births. RESULTS: A total of 1,005,052 births were reported to the Birth Defects Monitoring Network of Guangdong Province, of which 5268 cases were diagnosed as CHD. The overall prevalence of CHD was 52.41 per 10,000 births (95% CI: 51.00 ~ 53.83) in provincial-wide, 66.08 per 10,000 births (95% CI: 63.77 ~ 68.39) in urban areas, and 40.23 per 10,000 births (95% CI: 38.52 ~ 41.93) in rural areas. The prevalence of CHD increased with maternal age both in urban areas (P < 0.01) and in rural areas (P < 0.01). CONCLUSION: The increasing trends of CHD prevalence suggest that maternal age and the improvement of diagnosis ability might play a critical role.

High prevalence of thalassemia in migrant populations in Guangdong Province, China.

BACKGROUND: The objectives of this study were to estimate the prevalence of thalassemia and to analyze the need for public health services for migrant populations in different cities in Guangdong Province, China. METHODS: A cross-sectional survey was conducted in 21 cities of Guangdong Province. Twenty-three types of a- and ß-globin gene mutations were detected in a total of 14,230 pregnant women and 14,249 husbands. RESULTS: There was a 16.45% prevalence of thalassemia among the 28,479 individuals, and the prevalences of α-, ß-, and combined α-/ß- thalassemia were 12.03%, 3.80%, and 0.63%, respectively. Compared with the native city residents in the province, the migrants from within the province and the immigrants from outside the province had lower prevalences of thalassemia, but the prevalence values were >11%. CONCLUSIONS: The prevalence values for thalassemia gene mutations were high in all three population groups studied in Guangdong Province. The results indicate that all segments of the Guangdong population should be screened for thalassemia.

Ambient air pollution and birth defects in Haikou city, Hainan province.

BACKGROUND: Evidence shows exposure to ambient air pollution during pregnancy was associated with an increased risk of adverse birth outcomes, such as preterm birth, low birth weight and intrauterine growth retardation, but the results for birth defects have been inconsistent. METHODS: The data on birth defects was collected from the Birth Defects Monitoring Network of Haikou city. Air pollution data for PM10, SO2 and NO2 were obtained from Haikou Environmental Monitoring Center. Logistic regression analysis was used to evaluate these associations. RESULTS: The risk of birth defects was related to PM10 levels (adjusted OR = 1.039; 95% CI = 1.016-1.063) and SO2 levels (adjusted OR = 0.843; 95% CI = 0.733-0.969) for the second month of pregnancy. In the third month of pregnancy, the risk of birth defects was also related to PM10 levels (adjusted OR = 1.066; 95% CI = 1.043-1.090) and SO2 levels (adjusted OR = 0.740; 95% CI = 0.645-0.850). CONCLUSION: The study provides evidence that exposure to PM10 and SO2 during the second and third month of pregnancy may associated with the risk of birth defects.

Effectiveness of a prevention of mother-to-child HIV transmission program in Guangdong province from 2007 to 2010.

BACKGROUND: To achieve the goal of United Nations of elimination of new HIV infections, a program of prevention of mother-to-child transmission (PMTCT) was launched in Guangdong province. The objective of this study is to evaluate the effectiveness of the PMTCT program. METHODS: The retrospective cross-section analysis was conducted using the data of case reported cards of HIV positive mothers and their infants from 2007 to 2010 in Guangdong province, and 108 pairs of eligible subjects were obtained. We described the data and compared the rates of MTCT by various PMTCT interventions respectively. RESULTS: The overall rate of HIV MTCT was 13.89% (15) among 108 pairs of HIV positive mothers and their infants; 60.19% (65) of the mothers ever received ARVs, 80.56% (87) of infants born to HIV positive mothers ever received ARVs, but 16.67% (18) of the mothers and infants neither received ARVs. Among all the mothers and infants, who both received ARVs, received triple ARVs, mother received ARVs during pregnancy, and both received ARVs and formula feeding showed the lower rates of HIV MTCT, and the rates were 8.06%, 2.50%, 5.77%, and 6.67% respectively. In infants born to HIV positive mother, who received mixed feeding had a higher HIV MTCT up to 60.00%. Delivery mode might not relative to HIV MTCT. CONCLUSIONS: The interventions of PMTCT program in Guangdong could effectively reduce the rate of HIV MTCT, but the effectiveness of the PMTCT program were heavily cut down by the lower availability of the PMTCT interventions.