From geochemical background determination to pollution assessment of heavy metals in sediments and soils

Establishing geochemical background concentrations to distinguish the natural background from anthropogenic concentrations of heavy metals in sediments and soils is necessary to develop guidelines for environmental legislation. Due to the fact that the background concentrations strongly depend on geological characteristics such as mineral composition, grain size distribution and organic matter content, several normalization methods have been developed. Empirical (geochemical), theoretical (statistical) and integrated methods (combining both empirical and theoretical methods) are the main approaches described in literature for determination of geochemical background concentrations. In this review paper, the different approaches as well as the main normalization methods for heavy metal concentrations in sediments and soils will be discussed. Both geochemical background concentrations and added risk level (maximum permissible addition) should be taken into account for setting up legal threshold limits. Moreover, different approaches to evaluate the pollution status of heavy metals in sediments and soils, from Sediment/Soil Quality Guidelines to quantitative indices (Geo-accumulation Index-I_geo, Enrichment Factor-EF, Pollution Load Index-PLI and Risk assessment Code-RAC) will be presented. Although guidelines to establish whether a sediment or soil is polluted or not are generally only related to total metal concentrations, the available/reactive pool i.e., availability/reactivity of metals should be taken into account for sediment/soil pollution assessment.     

Prevalence,Awareness, Treatment,and Control of High Blood Pressure: A Population-Based Survey in Thai Nguyen,Vietnam

Background

Cardiovascular disease (CVD) is one of the leading causes of morbidity and mortality in Vietnam and hypertension (HTN) is an important and prevalent risk factor for CVD in the adult Vietnamese population. Despite an increasing prevalence of HTN in this country, information about the awareness, treatment, and control of HTN is limited. The objectives of this study were to describe the prevalence, awareness, treatment, and control of HTN, and factors associated with these endpoints, in residents of a mountainous province in Vietnam.

Methods

Data from 2,368 adults (age≥25 years) participating in a population-based survey conducted in 2011 in Thai Nguyen province were analyzed. All eligible participants completed a structured questionnaire and were examined by community health workers using a standardized protocol.

Results

The overall prevalence of HTN in this population was 23%. Older age, male sex, and being overweight were associated with a higher odds of having HTN, while higher educational level was associated with a lower odds of having HTN. Among those with HTN, only 34% were aware of their condition, 43% of those who were aware they had HTN received treatment and, of these, 39% had their HTN controlled.

Conclusions

Nearly one in four adults in Thai Nguyen is hypertensive, but far fewer are aware of this condition and even fewer have their blood pressure adequately controlled. Public health strategies increasing awareness of HTN in the community, as well as improvements in the treatment and control of HTN, remain needed to reduce the prevalence of HTN and related morbidity and mortality.     

Identification of a Potent Endothelium-Derived Angiogenic Factor

The secretion of angiogenic factors by vascular endothelial cells is one of the key mechanisms of angiogenesis. Here we report on the isolation of a new potent angiogenic factor, diuridine tetraphosphate (Up₄U) from the secretome of human endothelial cells. The angiogenic effect of the endothelial secretome was partially reduced after incubation with alkaline phosphatase and abolished in the presence of suramin. In one fraction, purified to homogeneity by reversed phase and affinity chromatography, Up₄U was identified by MALDI-LIFT-fragment-mass-spectrometry, enzymatic cleavage analysis and retention-time comparison. Beside a strong angiogenic effect on the yolk sac membrane and the developing rat embryo itself, Up₄U increased the proliferation rate of endothelial cells and, in the presence of PDGF, of vascular smooth muscle cells. Up₄U stimulated the migration rate of endothelial cells via P2Y2-receptors, increased the ability of endothelial cells to form capillary-like tubes and acts as a potent inducer of sprouting angiogenesis originating from gel-embedded EC spheroids. Endothelial cells released Up₄U after stimulation with shear stress. Mean total plasma Up₄U concentrations of healthy subjects (N = 6) were sufficient to induce angiogenic and proliferative effects (1.34±0.26 nmol L^-1). In conclusion, Up₄U is a novel strong human endothelium-derived angiogenic factor.     

Pareuchiloglanis (Teleostei: Sisoridae) from the Pearl River,China with description of three new species

We describe three new species of Pareuchiloglanis. Based on a comparison of 17 valid species of Pareuchiloglanis, the genus can be divided into two groups contingent on their gill opening size and the anus position. One group, which we call the large gill opening group, has a large gill opening extending to the base of the first pectoral-fin element; the anus is obviously closer to pelvic-fin insertion than the anal-fin origin; this group includes five species distributed in the Red and Pearl Rivers, China. The other group has a small gill opening extending only to the middle base of the pectoral-fin elements; the anus is usually located at the midpoint of the pelvic-fin insertion to the anal-fin origin or slightly behind. This group includes the other 12 species, which are distributed in the Mekong and Yangtze Rivers. The large-gill-opening group can be divided into two sub-groups based on the length of the caudal peduncle. One sub-group has a long caudal-peduncle and the distance from the anal-fin origin to caudal-fin base is greater than distance from the pelvic-fin insertion. This sub-group is only distributed in the Pearl River drainage. Another sub-group has a short caudal peduncle and the distance from the anal-fin origin to the caudal-fin base is typically smaller than the distance from the pelvic-fin insertion. This sub-group is only distributed in the Red River basin of China and Vietnam. The former will be called the large-gill-opening group with long caudal peduncle in the text and only includes one species P. longicauda. During our ongoing taxonomic work of specimens collected from Nanpan-jiang and Beipan-jiang (upper Pearl River drainage in Yunnan, China), some Pareuchiloglanis specimens that had the characters of the large-gill-opening group with long caudal peduncle represent three undescribed species.     

Role of Insulin Resistance in the Alzheimer's Disease Progression

Recent studies continue to find evidence linking Type 2 diabetes (T2D) with Alzheimer's disease (AD), the most common cause of dementia, a general term for memory loss and other cognitive abilities serious enough to interfere with daily life. Insulin resistance or dysfunction of insulin signaling is a universal feature of T2D, the main culprit for altered glucose metabolism and its interdependence on cell death pathways, forming the basis of linking T2D with AD as it may exacerbate Aβ accumulation, tau hyperphosphorylation and devastates glucose transportation, energy metabolism, hippocampal framework and promulgate inflammatory pathways. The current work demonstrates the basic mechanisms of the insulin resistance mediates dysregulation of bioenergetics and progress to AD as a mechanistic link between diabetes mellitus and AD. This work also aimed to provide a potential and feasible zone to succeed in the development of therapies in AD by enhanced hypometabolism and altered insulin signaling.

     

Type locality and species identity of Pareuchiloglanis sinensis (Hora & Silas) with a description of a new species of the genus from the upper Yangtze River basin in southern China

The genus Pareuchiloglanis, distributed in the Salween, Mekong, Red, Pearl and Yangtze River basins in China, Laos, Myanmar and Vietnam, consists of 20 valid species and 5 uncertain species. This study provided a taxonomic revision to Pareuchiloglanis occurring in the Yangtze River. According to the results of a morphological comparison, the type locality of Pareuchiloglanis sinensis was updated to the Nanpan-jiang (the upper Pearl River) basin; five species were identified in Pareuchiloglanis from the Yangtze River basin. Specimens formerly identified as Pareuchiloglanis sinensis from this basin were described as a new species, Pareuchiloglanis chui sp. nov. Moreover, Pareuchiloglanis tianquanensis was synonymized with Pareuchiloglanis sichuanensis. This study provided a key to these two species and three others (Pareuchiloglanis anteanalis, Pareuchiloglanis hupingshanensis and Pareuchiloglanis robusta) from the Yangtze River basin, including information about their geographical distribution. These findings provide an insight into the evolution, distribution and taxonomy of this genus for future studies.     

Association between variants of EXT2 and type 2 diabetes: a replication and meta-analysis

Recent publications have found an association between variants of exostosin 2 (EXT2) gene and the risk of type 2 diabetes in some population but not in others. In an attempt to address these inconsistencies, we investigated EXT2 variants in two independent cohorts, and conducted a literature-based meta-analysis. Through regression model, we assessed the relationship between the EXT2 single nucleotide polymorphisms (SNPs) (rs3740878, rs11037909 and rs1113132) and the risk of type 2 diabetes in Han Chinese population, including a total of 2,533 cases and 2,643 controls. We combined our data with that from previously published studies and performed a meta-analysis to evaluate the effect size of the gene. Consistent with some studies, we found marginal association for the rs3740878 (OR = 1.07, 95 % CI = 0.99, 1.16, p = 0.09), rs11037909 (OR = 1.07, 95 % CI = 0.99, 1.16, p = 0.08), and rs1113132 (OR = 1.08, 95 % CI = 1.00, 1.17, p = 0.06) in our 2 cohorts. Meta-analysis, comprising 9,224 type 2 diabetes and 10,484 controls, revealed that three SNPs (rs3740878, rs11037909 and rs1113132) in EXT2 were significantly associated with type 2 diabetes (ORs range from 1.06 to 1.07, p = 0.038, p = 0.008 and p = 0.005, respectively). Variation in the EXT2 locus appears to be associated with a small increase in the risk of type 2 diabetes. However, well-designed prospective studies with larger sample size and more ethnic groups are needed to further validate the results.