Amino accelerators and antioxidants in sediments from the Dong Nai River System, Vietnam: Distribution and influential factors.

Amino accelerators and antioxidants (AAL/Os) have become a suite of contaminants of emerging concern recently due to the accumulating evidence for their environmental occurrence and associated toxic potential. Nevertheless, data on sedimentary deposition of AAL/Os has remained scarce, particularly for regions beyond the North America. In the present study, we elucidated spatial distribution of fifteen AAL/Os and five AAO transformation products (AAOTPs) in seventy-seven sediments from the Dong Nai River System (DNRS), Vietnam. Total concentrations of AAL/Os (∑AAL/Os) ranged from 0.377 to 51.4 ng/g (median: 5.01 ng/g). 1,3-Diphenylguanidine and 4,4'-bis(1,1-dimethylbenzyl) diphenylamine were the two most prevalent congeners, both with detection frequencies >80%. Additionally, AAOTPs were quantifiable in 79% of the DNRS sediments with a median ∑AAOTPs at 2.19 ng/g, dominated by N, N'-diphenylbenzidine and 2-nitrodiphenylamine. Higher sediment-associated levels of AAL/Os and AAOTPs were spotted in downstream and the primary tributary of the DNRS compared to the upstream, implying their cumulative sedimentation towards the estuarine region. The distribution patterns of AAL/Os and AAOTPs across individual transects also demonstrated the influence of human activities (e.g., urbanization and agriculture), hydrodynamics, and decontamination by mangrove reserves. Meanwhile, characteristics of sediments, i.e., total organic carbon (TOC) content and grain sizes, exhibited significant correlations with the burdens of these compounds, indicating their preferential partitioning into the fine and TOC-rich matter. This research sheds light on environmental behavior of AAL/Os and AAOTPs beneath Asian aquatic system, and highlights the need for further evaluation of their impacts on the wildlife and public health.

The Potential Roles of CHI3L1 in Failed Autologous Arteriovenous Fistula in End-Stage Renal Disease.

Autologous arteriovenous fistula (AVF) is commonly placed for hemodialysis treatment. Recent studies show that increased baseline serum level of Chitinase-3-like protein 1 (CHI3L1) is independently associated with a higher risk of the early failure of forearm AVFs. However, the changes and mechanisms of CHI3LI in local vascular tissues of failed AVF have not be revealed. This study aims to conduct the expression and mechanism of CHI3L1 in vascular tissues from patients. Immunoreactivity of CHI3L1, matrix metalloproteinase 2 (MMP-2) and vascular endothelial growth factor-A (VEGF-A) were detected in vascular tissues collected from nine patients with AVF surgery. Due to the significant stenosis clinically, six of the nine patients received arteriovenous fistula reconstruction. The expression differences of CHI3L1 between the initial vascular tissues and failed AVF are significant (P < 0.05). Failed AVF due to stenosis shows intraluminal thrombus, collagen fiber rupture, fibrous connective tissue hyperplasia, tube wall thickening, neovascularization, scattered inflammatory cell infiltration in the tunica media as well as high CHI3L1 expression level, and the expression of MMP-2 (r = 0.9022, P = 0.0139) and VEGF-A (r = 0.8355, P = 0.0393) was positively correlated with CHI3L1. CHI3L1 expression in vascular tissues possibly plays an important role in AVF failure. MMP-2 and VEGF-A may participate in venous stenosis with CHI3L1.

Equity and efficiency of maternal and child health resources allocation in Hunan Province, China.

BACKGROUND: A reasonable allocation of health resources is often characterized by equity and high efficiency. This study aims to evaluate the equity and efficiency of maternal and child health (MCH) resources allocation in Hunan Province, China. METHODS: Data related to MCH resources and services was obtained from the Hunan maternal and child health information reporting and management system. The Gini coefficient and data envelopment analysis (DEA) were employed to evaluate the equity and efficiency of MCH resources allocation, respectively. RESULTS: The MCH resources allocation in terms of demographic dimension were in a preferred equity status with the Gini values all less than 0.3, and the Gini values for each MCH resources' allocation in terms of the geographical dimension ranged from 0.1298 to 0.4256, with the highest values in the number of midwives and medical equipment (≥ CNY 10,000), which exceeds 0.4, indicating an alert of inequity. More than 40% regions in Hunan were found to be relatively inefficient with decreased return to scale in the allocation of MCH resources, indicating those inefficient regions were using more inputs than needed to obtain the current output levels. CONCLUSIONS: The equity of MCH resources by population size is superior by geographic area and the disproportionate distribution of the number of medical equipment (≥ CNY 10,000) and midwives between different regions was the main source of inequity. Policy-makers need to consider the geographical accessibility of health resources among different regions to ensure people in different regions could get access to available health services. More than 40% of regions in Hunan were found to be inefficient, with using more health resources than needed to produce the current amount of health services. Further investigations on factors affecting the efficiency of MCH resources allocation is still needed to guide regional health plans-making and resource allocation.

Distribution of organophosphate esters influenced by human activities and fluvial-tidal interactions in the Dong Nai River System, Vietnam.

Limited information is known about organophosphate esters (OPEs) in sediments of the Dong Nai River System (DNRS) in Vietnam and the influences of complex hydro-sedimentary dynamics on their fate. In this study, 48 surface sediment samples were collected from the Dong Nai-Soai Rap River and its tributary Vam Co River for the determination of 11 target OPEs, together with grain size and total organic carbon (TOC). The total concentrations of OPEs were in the range of 39.4 ng/g dw-373 ng/g dw (mean: 128 ng/g dw), and tris(1-chloro-2-propyl) phosphate (TCPP) was the predominant one with an average contribution of 81%, followed by tri-n-butyl phosphate (TNBP), tris(2-ethylhexyl) phosphate (TEHP). The composition profiles of OPEs at different locations of the DNRS showed no significant differences (p > 0.05). In addition, the distribution of OPEs had been influenced by both human activities and the fluvial-tidal interactions. The highly frequent and various human activities in Ho Chi Minh City (HCMC) leaded to the highest total concentration of OPEs in the midstream site. Based on our dataset, TOC content and grain size of sediments had significant correlation with certain OPEs (p < 0.05), and sediments with higher TOC content and finer grain size in the DNRS were more likely to be deposited in the downstream reach, contributing to the estuary of the DNRS was identified as another hotspot with the second highest concentration of OPEs. Furthermore, the distribution of OPEs in the transects had distinct characteristics, which reflected the joint influence of the human activities and fluvial-tidal interaction as well. However, the mechanism of their influence needed further investigation.

Abandonment and rapid infilling of a tide-dominated distributary channel at 0.7 ka in the Mekong River Delta.

The Ba Lai distributary channel of the Mekong River Delta was abandoned and infilled with sediment during the Late Holocene, providing a unique opportunity to investigate the sediment fill, timing and mechanisms of channel abandonment in tide-dominated deltaic systems. Based on analysis and age dating of four sediment cores, we show that the channel was active since 2.6 ka and was abandoned at 0.7 ka as marked by the abrupt disappearance of the sand fraction and increase in organic matter and sediment accumulation rate. We estimate that the channel might have been filled in a time range of 45-263 years after detachment from the deltaic network, with sediment accumulation rates of centimetres to decimetres per year, rapidly storing approximately 600 Mt of organic-rich mud. We suggest that the channel was abandoned due to a sediment buildup favoured by an increase in regional sediment supply to the delta. This study highlights that mechanisms for abandonment and infilling of tide-dominated deltaic channels do not entirely fit widely used models developed for fluvial-dominated environments. Their abandonment might be driven by autogenic factors related to the river-tidal and deltaic dynamics and favoured by allogenic factors (e.g., human impact and/or climate change).

Mother-to-child transmission prevention of human immunodeficiency virus, syphilis and hepatitis B virus.

BACKGROUND: China is the first country to initiate a nationwide program for prevention of mother-to-child transmission of human immunodeficiency virus, syphilis and hepatitis B virus by an integrated approach. However, the progress of this program remains unreported at national or local level for China. Therefore, we performed a hospital-based longitudinal study to assess the integrated prevention effect in Hunan, South-central China. METHODS: This study was conducted at 123 counties in Hunan and covered all local hospitals providing midwifery and antenatal care services from 2010 to 2016. We used the Cochran-Armitage test to examine the temporal changes of the indicators related with prevention of mother-to-child transmission. Besides, we used Spearman rank correlation analysis to assess the association between mother-to-child transmission rates and the process indicators related with prevention of mother-to-child transmission. RESULTS: After implementation of integrated prevention program, the indicators related with prevention of mother-to-child transmission are moving in the right direction. From 2010 to 2016, mother-to-child transmission rates significantly decreased from 19.4% to 9.6% for human immunodeficiency virus, and from 116.3 to 13.6 cases per 100,000 live births for syphilis. The proportion of children receiving hepatitis B immunoglobulin injection within 24h after birth increased from 95.2% to 98.9% among exposed neonates. Mother-to-child transmission rates were negatively associated with the process indicators related with prevention of mother-to-child transmission (all P<0.05). CONCLUSIONS: Our prevention program of mother-to-child transmission for three diseases by an integrated approach proved to be viable and effective. Our model may be of interest to other countries.

Detangling the Effects of Environmental Filtering and Dispersal Limitation on Aggregated Distributions of Tree and Shrub Species: Life Stage Matters.

The pervasive pattern of aggregated tree distributions in natural communities is commonly explained by the joint effect of two clustering processes: environmental filtering and dispersal limitation, yet little consensus remains on the relative importance of the two clustering processes on tree aggregations. Different life stages of examined species were thought to be one possible explanation of this disagreement, because the effect of environmental filtering and dispersal limitation are expected to increase and decrease with tree life stages, respectively. However, few studies have explicitly tested these expectations. In this study, we evaluated these expectations by three different methods (species-habitat association test based on Poisson Clustering model and spatial point pattern analyses based on Heterogeneous Poisson model and the jointly modeling approach) using 36 species in a 20-ha subtropical forest plot. Our results showed that the percentage of species with significant habitat association increased with life stages, and there were fewer species affected by dispersal limitation in later life stages compared with those in earlier stages. Percentage of variance explained by the environmental filtering and dispersal limitation also increases and decreases with life stages. These results provided a promising alternative explanation on the existing mixed results about the relative importance of the two clustering processes. These findings also highlighted the importance of plant life stages for fully understanding species distributions and species coexistence.

[Applicability analysis of spatially explicit model of leaf litter in evergreen broad-leaved forests].

The spatially explicit model of leaf litter can help to understand its dispersal process, which is very important to predict the distribution pattern of leaves on the surface of the earth. In this paper, the spatially explicit model of leaf litter was developed for 20 tree species using litter trap data from the mapped forest plot in an evergreen broad-leaved forest in Tiantong, Zhejiang Pro- vince, eastern China. Applicability of the model was analyzed. The model assumed an allometric equation between diameter at breast height (DBH) and leaf litter amount, and the leaf litter declined exponentially with the distance. Model parameters were estimated by the maximum likelihood method. Results showed that the predicted and measured leaf litter amounts were significantly correlated, but the prediction accuracies varied widely for the different tree species, averaging at 49.3% and ranging from 16.0% and 74.0%. Model qualities of tree species significantly correlated with the standard deviations of the leaf litter amount per trap, DBH of the tree species and the average leaf dry mass of tree species. There were several ways to improve the forecast precision of the model, such as installing the litterfall traps according to the distribution of the tree to cover the different classes of the DBH and distance apart from the parent trees, determining the optimal dispersal function of each tree species, and optimizing the existing dispersal function.

[Evaluation on effect of treatment and assistance to advanced schistosomiasis patients in Hunan Province from 2004 to 2013].

OBJECTIVE: To comprehensively evaluate the effect of the program of treatment and assistance to advanced schistosomiasis patients in Hunan Province from 2004 to 2013. METHODS: The fund investment of the program, the profits of hospitals and the improvement of the patients' health were investigated by data collection and questionnaire survey. The evaluation index system of treatment and assistance to advanced schistosomiasis in Hunan Province was constructed by the Delphi method and analytic hierarchy process, and the program was assessed comprehensively. RESULTS: The evaluation index system including 6 primary indices and 33 secondary indices was established. Among all the primary indices, the score of the treatment and assistance (22.25) was the highest, and that of the satisfaction assessment (8.15) was the lowest, and the score of the comprehensive assessment was 87.06. The average cure rate of the patients was 13.08% from 2004 to 2013. More than 60% of the patients' disease condition got better, and nearly 70% of the patients' psychological condition improved, and more than 70% of patients' self-help ability and social contact improved, as well as family happiness increased. In addition, the annual average cost for caretakers decreased by 2000 Yuan, and the profits of all the fixed-point hospitals for treatment and assistance increased. CONCLUSION: The effectiveness and efficiency of the treatment and assistance to advanced schistosomiasis patients in Hunan Province is obvious, and the government should continuously invest in the program.

[Multi-disciplinary treatment for advanced schistosomiasis].

OBJECTIVE: To assess the efficiency of multi-disciplinary treatment (MDT) for advanced schistosomiasis. METHODS: A total of 173 advanced schistosomiasis patients who received MDT were selected from January 2010 to December 2011. These patients included 75 splenomegaly cases and 98 ascites cases. Other 193 advanced schistosomiasis patients who received single-discipline treatment (SDT) from January 2007 to December 2009 were also selected, and of them 84 cases were splenomegaly and 109 were ascites. The clinical efficiencies of the two different treatments were analyzed and assessed. RESULTS: Compared to the SDT group, the splenomegaly cases treated by MDT showed a shorter pre-operative preparation time and less days in hospitalization (both P < 0.01), less operation duration, decreased post-operative complications, lower hospitalization costs (all P < 0.05), and less patient complaints (P > 0.05). The ascites cases treated by MDT, compared to the SDT group, had less pre-treatment time, shorter ascites-disappearing time (both P <0.01), and less hospitalization duration, decreased post-treatment complications, lower hospitalization costs and less patient complaints (all P < 0.05). Conclusion MDT has a better efficiency in the treatment of advanced schistosomiasis, and it reduces the operation complications and improves the life quality of the patients.

[Retrospective survey of 184 patients infected with Schistosoma haematobium from African countries].

OBJECTIVE: To understand the status of persons of export of labor services infected with Schistosoma haematobium. METHODS: A total of 184 suspected hospitalized patients infected with S. haematobium were investigated retrospectively. RESULTS: Among the patients, 111 used to work in Angola (60.3%) and 57 in Mozambique (31.0%). Pathogenic examinations were done in 13 cases, and S. haematobium eggs were found in 6 subjects. Totally 96.7% of patients showed antibody positive by the tests of IHA and ELISA. A total of 112 subjects (60.9%) had urinary tract symptoms, and 52 had fatigue. However, 72 subjects (39.1%) did not have any signs and symptoms. CONCLUSIONS: There are some persons of export of labor services who are infected with S. haematobium. Therefore, we suggest that the authority should establish a program for prevention and treatment of schistosomiasis haematobia and schistosomiasis mansoni in persons of export of labor services.