[Health Risk Assessment of Heavy Metals in Soils of a City in Guangdong Province Based on Source Oriented and Monte Carlo Models].

Taking a city in Guangdong Province as the research area, the concentration and spatial distribution characteristics of heavy metals in the surface soil were studied to clarify the situation of soil heavy metal pollution and priority control factors, providing basic data for the prevention and control of soil heavy metal pollution in the city. The content characteristics of heavy metals in 221 soil samples in the city were analyzed, and the potential health risk assessment and source analysis were carried out through the Monte Carlo model, the potential health risk assessment (HRA) model, and the PMF receptor model. It was found that heavy metals ω(As), ω(Hg), ω(Cd), ω(Pb), ω(Cr), ω(Cu), ω(Ni), and ω(Zn) in the soil of the city were 18.16, 0.43, 1.46, 68.57, 98.34, 64.19, 26.53, and 257.32 mg·kg-1, respectively, with a moderate to high degree of variation. Except for Ni concentration, the soil concentrations of other heavy metal elements exceeded the background values of soil in Guangdong Province to a certain extent, and the concentrations of Cd and Zn exceeded the national secondary standards, resulting in severe heavy metal pollution; the main sources of heavy metals were industrial sources, and natural parent materials, lead battery manufacturing, transportation, artificial cultivation, and pesticide and fertilizer inputs also had an undeniable impact on the accumulation of heavy metals in the soil. Heavy metals in the soil had a certain degree of tolerable carcinogenic health risk for both children and adults, whereas non-carcinogenic risks could be ignored. The potential health risk of children was greater than that of adults, and the main exposure route was through oral intake. The input sources of pesticides and fertilizers and As should be the main controlling factors for the health risks of heavy metals in the city's soil, followed by mixed sources and Cr. There were differences in the spatial distribution characteristics and relative pollution levels of heavy metals, and it is necessary to deepen zoning monitoring and control, strengthen soil pollution prevention and control, and reduce human input of heavy metals in soil.

[Pollution Characteristics and Risk Assessment of Polycyclic Aromatic Hydrocarbons in Soils of Guangzhou].

In order to comprehensively study the pollution characteristics of polycyclic aromatic hydrocarbons （PAHs） in soils of Guangzhou， 222 topsoil samples were collected and analyzed. The ecological risk of soil PAHs pollution was evaluated using the effect interval low/median method （ERL/ERM） and the （BaP） toxicity equivalent method， and the health risk of soil PAHs pollution was evaluated using the lifelong cancer risk increment model. The source of PAHs was analyzed using the characteristic compound ratio method and PMF model. The results indicated that： the content of surface soil （∑16PAHs） in Guangzhou was 38-11 115 µg·kg-1， with an average of 526 µg·kg-1， and 16 types of polycyclic aromatic hydrocarbon monomers showed strong variation. There was a certain degree of ecological risk of PAHs in Guangzhou， and there was already a significant ecological risk of PAHs pollution in individual sampling points， which were generally in a state of mild pollution. Based on the results of the health risk assessment， the contribution rates of total cancer risk in both adults and children were presented as follows： skin contact > ingestion of soil > respiratory intake. The health risk of children was greater than that of adults， and the overall health risk was within an acceptable range. Source analysis showed that the main sources of soil PAHs in Guangzhou were coal （37.1%）； diesel （32%）； coking （17.3%）； and mixed sources of traffic emissions， biomass combustion， and petrochemical product volatilization （13.6%）. The overall source of soil PAHs belonged to mixed sources. The research results have enriched our understanding of the pollution status of PAHs in the surface soil of Guangzhou and are helpful in promoting soil pollution prevention and control actions.

Human chorionic gonadotropin improves endometriosis through downregulation of leptin expression in rats.

OBJECTIVE: To investigate whether and how human chorionic gonadotropin (HCG) treatment ameliorates endometriosis in an endometriotic rat model. METHODS: Twenty-four endometriosis rats were established and were randomly divided into four groups, and then the rats were treated with 19.4, 25.8, and 51.6 IU/100 g weight/day of HCG, respectively. The control group was treated with 0.9% NaCl. After 15 days (3 estrous cycles), the ectopic lesion volume and the expression of leptin protein in eutopic and ectopic endometrium were investigated. RESULTS: After HCG treatment, the volumes of endometriotic lesions were significantly smaller than those before treatment. During endometriosis development, the expression of leptin protein in eutopic and ectopic endometrium was remarkably increased. HCG administration reversed leptin upregulation in endometriotic tissues. CONCLUSION: HCG therapy appears to be an effective treatment for endometriosis in rats through down-regulation of leptin expression in eutopic and ectopic endometrium.

Placental methylation markers in normal and trisomy 21 tissues.

OBJECTIVE: The objective of this study is to combine multiplex ligation-dependent probe amplification (MLPA) and bisulfite sequencing to determine DNA methylation markers for noninvasive prenatal diagnosis of Down syndrome. METHODS: DNA methylation ratios (MR) of four fragments (CGI149, CGI045, HLCS-1, and HLCS-2) on chromosome 21 were evaluated in blood cells from 13 nonpregnant women, 15 euploidies, and 11 Down Syndrome (DS) placentae. Ratios were measured by bisulfite sequencing and methylation-specific (MS)-MLPA. RESULTS: The MS-MLPA and bisulfite sequencing results were concordant. CGI149, CGI045, and HLCS-2 were unmethylated in all nonpregnant blood cells. CGI149, CGI045, HLCS-1, and HLCS-2 were methylated in most of the euploid (13, 11, 15, and 15, respectively) and DS placentae (10, 11, 11, and 11, respectively). The median placental DNA MR in CGI149 was 0.4578 (interquartile range, 0.3568-0.5169) and 0.5918 (interquartile range, 0.5618-0.6659) in euploid and DS placentae, respectively (p = 0.001). Using placental MR at 0.5390 as a threshold, we detected DS at 90.9% sensitivity and 93.3% specificity. CONCLUSION: The MS-MLPA is an effective alternative to bisulfite sequencing in assessing placental MR. CGI149 is a potential marker for the noninvasive diagnosis of Down syndrome.

Development of strategies for screening, predicting, and diagnosing intrauterine HBV infection in infants born to HBsAg positive mothers.

This study aimed at developing strategies for screening, predicting, and diagnosing intrauterine HBV infection in infants born to HBsAg positive mothers. A total of 1,360 infants born to 1,355 HBsAg positive mothers were followed for 1 year. All newborn infants received active and passive immunization within 24 hr after birth. Maternal and infant blood samples were collected and tested for the status of serum HBsAg, HBeAg, and HBV DNA positivity. The accuracy of infant HBsAg positivity, HBV DNA positivity, HBsAg and HBV DNA double positivity, and HBsAg and/or HBV DNA positivity at birth in the diagnosis of intrauterine HBV infection was evaluated by receiver operating characteristic curve analysis. Of 1,360 infants, 145 tested positive for HBsAg and/or HBV DNA at birth. Twenty-one (1.5%) infants, who were diagnosed with intrauterine HBV infection, showed HBsAg positivity from birth to 7 and 12 months of age. Infant HBsAg positivity at birth had the highest sensitivity in predicting intrauterine HBV infection, while neonatal HBsAg and HBV DNA double positivity had the highest specificity. These findings suggest that infants, who were born to HBsAg positive mothers and were positive for both HBsAg and HBV DNA at birth, may be at a higher risk for intrauterine HBV infection. HBsAg positivity at birth may be a good marker for screening intrauterine HBV infection. Infant HBsAg positivity both at birth and 7 months of age may be used as a diagnostic criterion to simplify diagnostic procedures and improve diagnostic efficiency.

[Identification of risk factors related to the failure of immunization to interrupt hepatitis B virus perinatal transmission].

OBJECTIVE: To explore the factors influencing failure of an immunization to interrupt perinatal (mother-to-child) transmission of hepatitis B virus (HBV). METHODS: Between June 2006 and March 2010, a total of 1355 pregnant women testing positive for the hepatitis B surface antigen (HBsAg), at gestational weeks 20 to 42, and without use of antiviral or immunomodulatory drugs during the pregnancy were prospectively recruited to the study. The mothers were given a choice of receiving hepatitis B immunoglobulin (HBIG; three 200 IU intramuscular injections give at four-week intervals starting from gestation week 28) or not. All neonates (1360, including five sets of twins) received hepatitis B vaccine (10 mug) plus HBIG (200 IU) combined immunization within 24 h of birth, as early as possible. Peripheral venous blood samples were collected from the neonates within 24 h of birth and at 7 and 12 months of age for detection of HBV markers, including hepatitis B e antigen (HBeAg) and HBV DNA. The infants were classified according to HBV perinatal transmission status (infection group and non-infection group) and various factors (maternal-related: age, gravidity, parity; pregnancy/birth-related: threatened premature labor, complications; neonate-related: sex, birth weight, apgar score) were compared between the two groups by using non-conditional logistic regression analysis to determine their potential influence on failure of immunization to inhibit transmission. RESULTS: After 12 months of follow-up, 1.54% (21/1360) of the neonates had presented with HBV infection. Analysis of the HBV-infected neonates revealed differences in infection rates between neonates born to mothers with HBIG injection (2.22% vs. without HBIG injection: 1.11%, P less than 0.05) and caesarean section (1.35% vs. vaginal delivery: 1.73%) but neither reached statistical significance (P less than 0.05); only the practice of breastfeeding showed a significant difference for infection rate, with neonates fed artificial formula having higher infection rate (3.13%) than the breastfed neonates (0.27%, P less than 0.05). The neonate HBV infection rate was also significantly higher for neonates born to HBeAg-positive mothers (4.44% vs. HBeAg-negative mothers: 0%, P less than 0.05) and HBV DNA-positive mothers (3.13% vs. HBV DNA-negative mothers: 0%, P less than 0.05). When the mothers were stratified by serum level of HBV DNA, there was a significant difference in HBV-infected neonates born to mothers with more than or equal to 1*10(7) IU/ml(6.01% vs. 10(3)-10(6) IU/ml: 0.56% and less than 1*10(3) IU/ml: 0%, both P less than 0.05). Logistic regression analysis indicated that the independent risk factors for HBV perinatal transmission despite immunization were maternal serum HBeAg-positive status (relative risk (RR)=31.74, 95% confidence interval (CI): 3.88-259.38) and maternal HBV DNA of ≥ 107 copies/mL (RR=22.58, 95% CI: 4.75-107.40). CONCLUSION: Failure of vaccine plus HBIG to interrupt mother-to-child transmission of HBV is influenced by maternal serum HBeAg-positive status and maternal HBV DNA of ≥107 copies/mL.

Is axillary dissection necessary for breast cancer in old women? A meta-analysis of randomized clinical trials.

BACKGROUND: We performed this meta-analysis to assess the effectiveness and safety of axillary dissection in old women. METHODS: The Cochrane Library, PubMed, EMBASE and Chinese Biomedical Literature Database were searched and all randomized controlled trials of axillary dissection in old women (at least 60 years old) were considered. Meta-analyses were completed using RevMan5.1. RESULTS: Three eligible randomized controlled trials (RCTs) including 5,337 patients were considered. There was weak evidence in favour of axillary dissection (AD) in old women. The meta-analysis showed that the overall survival (OS) after 1, 3, 5 and 7 years and the disease free survival (DFS) after 1, 3 and 5 year were not statistically significantly different between AD and no AD groups. However, there was a difference in the 7 year DFS. CONCLUSIONS: Axillary dissection did not provide survival benefit to the old women with breast cancer analysed. Therefore, axillary dissection is not well-indicated in old women with breast cancer.