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The North China Plain faces increasing pressure on fresh water resources due to economic development and climate variations. The effects of climate variations and human activities on the groundwater system in Tianjin, Northern China, were analyzed using an autoregressive integrated moving average model. Our result showed that the groundwater dynamics were influenced by climatic factors and that human activities gradually played a dominant role in the increasing groundwater withdrawal. During the period of 1950–2010, there were no significant trends in annual and wet season precipitation based on Mann–Kendall tests at the 5% significance level. Surface air temperature significantly increased, but potential evapotranspiration and phreatic water evaporation were not significantly changed. The effect of precipitation on groundwater-level fluctuation was decreasing, and the groundwater level declines mainly resulted from the groundwater withdrawal in Tianjin. Sustainable management of groundwater resources in the North China Plain will largely hinge on sustainable management of groundwater withdrawal, especially the efficient use of water for agriculture production. [ABSTRACT FROM AUTHOR]

Epichloë endophytes can not only affect the growth and resistance of the host plant but also change the biotic and abiotic properties of the soil where the host is situated. Here, we used endophyte-infected (EI) and endophyte-free (EF) Leymus chinensis as plant materials, to study the microbial diversity and composition in the host root endosphere and rhizosphere soil under both pot and field conditions. The results showed that endophyte infection did not affect the diversity of either bacteria or fungi in the root zone. There were significant differences in both bacterial and fungal communities between the root endosphere and the rhizosphere, and between the field and the pot, while endophytes only affected root endosphere microbial communities. The bacterial families affected by endophyte infection changed from 29.07% under field conditions to 40% under pot conditions. In contrast, the fungal families affected by endophyte infection were maintained at nearly 50% under both field and pot conditions. That is to say, bacterial communities in the root endosphere were more strongly affected by environmental conditions, and in comparison, the fungal communities were more strongly affected by species specificity. Endophytes significantly affected the fungal community composition of the host root endosphere in both potted and field plants, only the effect was more obvious in potted plants. Endophyte infection increased the abundance of three fungal families (Thelebolaceae, Herpotrichiellaceae and Trimorphomycetaceae) under both field and potted conditions. In potted plants, endophytes also altered the dominant fungi from pathogenic Pleosporales to saprophytic Chaetomiaceae. Endophyte infection increased the relative abundance of arbuscular mycorrhizal fungi and saprophytic fungi, especially under potted conditions. Overall, endophytes significantly affected the fungal community composition of the host root endosphere in both potted and field plants. Endophytes had a greater impact on root endosphere microorganisms than the rhizosphere, a greater impact on fungal communities than bacteria, and a greater impact on root endosphere microorganisms under potted conditions than at field sites. [ABSTRACT FROM AUTHOR]

Regions that have large coal consumption could be prone to elevated concentrations of atmospheric trace metals. Snow samples were collected at two sites in Tianjin, northern China, during three heating seasons and analyzed for major and trace elements. Concentrations were assessed for compliance with Chinese and US EPA Water Quality Standards for Surface Waters, and it was established that trace metals except Cd were present at concentrations below these standards. Enrichment factors showed that, in comparison with local top soils, Se, Hg, Cd, and Zn were highly enriched and As, Cu, Ni, and Pb were moderately enriched, suggesting that these metals were contributed primarily via anthropogenic activities. Concentrations of Mn, Co, Cr, V, and Al were not enriched and were mostly of crustal origin. Backward trajectories were calculated for each snow event using the NOAA HYSPLIT model. The transport characteristics and origins of the air masses were examined, which indicated that the elevated concentrations of Hg, Se, Cd, Zn, and As were influenced mainly by coal burning activities in northern China during the heating season. The results of this study revealed that anthropogenic activities have significant effect on snow water quality and thus, heavy metal emissions from coal consumption should be regulated more tightly. [ABSTRACT FROM AUTHOR]

Background: Primary vesicoureteral reflux (PVUR) is the most common malformation of the kidney and urinary tract, and reflux nephropathy is a major cause of chronic kidney disease in children. Recently, we reported mutations in the tenascin XB gene ( TNXB) as a cause of PVUR with joint hypermobility. Methods: To define the role of rare variants in tenascin genes in the etiology of PVUR, we screened a cohort of patients with familial PVUR (FPVUR) and non-familial PVUR (NFPVUR) for rare missense variants in TNXB and the tenascin C gene ( TNC) after excluding mutations in ROBO2 and SOX17. Results: The screening procedure identified 134 individuals from 112 families with PVUR; two families with mutations in ROBO2 were excluded from further analysis. Rare missense variants in TNXB were found in the remaining 110 families, of which 5/55 (9 %) families had FPVUR and 2/55 (4 %) had NFPVUR. There were no differences in high-grade reflux or renal parenchymal scarring between patients with and without TNXB variants. All patients with TNXB rare variants who were tested exhibited joint hypermobility. Overall we were able to identify causes of FPVUR in 7/57 (12 %) families (9 % in TNXB and 3 % in ROBO2). Conclusions: In conclusion, the identification of a rare missense variant in TNXB in combination with a positive family history of VUR and joint hypermobility may represent a non-invasive method to diagnose PVUR and warrants further evaluation in other cohorts. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) in coal, fly ash, slag, atmospheric deposition, soils and sediments collected from Tianjin, northern China, were measured to provide baseline information and determine possible Cd sources and potential risk. The concentrations of Cd in coal, fly ash and atmospheric deposition were much higher than the soil background values. Fallout from coal-fired thermal power plants, heating boilers and industrial furnaces has increased the Cd concentration in soils and sediments in Tianjin. The concentrations of Cd in soils of suburban areas were significantly higher than in rural areas, suggesting that coal burning in Tianjin may have an important impact on the local physical environment. Cd from coal combustion is readily mobilized in soils. It is soluble and can form aqueous complexes and permeate river sediments. The high proportion of mobile Cd affects the migration of Cd in soils and sediments, which may pose an environmental threat in Tianjin due to the exposure to Cd and Cd compounds via the food chain. This study may provide a window for understanding and tracing sources of Cd in the local environment and the risk associated with Cd bioaccessibility. [ABSTRACT FROM AUTHOR]

Focal and segmental glomerulosclerosis (FSGS) is the most common glomerular cause of end-stage kidney disease (ESKD). Although the etiology of FSGS has not been fully elucidated, recent results from the positional cloning of genes mutated in nephrotic syndromes are now beginning to provide insight into the pathogenesis of these diseases. Mutations in PLCE1/NPHS3 have recently been reported as a cause of nephrotic syndrome characterized by diffuse mesangial sclerosis (DMS) histology. One single family with a missense mutation had late onset of the disease that was characterized by FSGS. To further define the role of PLCE1 mutations in the etiology of FSGS, we performed mutational analysis in 69 families with FSGS. A total of 69 families with 231 affected individuals were examined. The median age of disease onset was 26 years (range 1–66 years). Onset of ESKD was at a median age of 35.5 years. Seven variants leading to non-synonymous changes were found, of which only two are new variants (exon 4 c.1682 G>A R561Q, exon 31 c.6518A>G K2173R). No known disease-causing mutations were identified in the families screened. PLCE1/NPHS3 mutations are not a cause of FSGS in this cohort. The absence of mutations in PLCE1/NPHS3 in this study indicates that there are additional genetic causes of FSGS and that hereditary FSGS is a heterogeneous disease. Kindreds appropriate for genome-wide screening are currently being subjected to analysis with the aim of identifying other genetic causes of FSGS. [ABSTRACT FROM AUTHOR]

Mutations in the LIM homeobox transcription factor 1-beta (LMX1B) are a cause of nail patellar syndrome, a condition characterized by skeletal changes, glaucoma and focal segmental glomerulosclerosis. Recently, a missense mutation (R246Q) in LMX1B was reported as a cause of glomerular pathologies without extra-renal manifestations, otherwise known as nail patella-like renal disease (NPLRD). We have identified two additional NPLRD families with the R246Q mutation, though the mechanisms by which LMX1BR246Q causes a renal-specific phenotype is unknown. In this study, using human podocyte cell lines overexpressing either myc-LMX1BWT or myc-LMX1BR246Q, we observed dominant negative and haploinsufficiency effects of the mutation on the expression of podocyte genes such as NPHS1, GLEPP1, and WT1. Specifically, we observed a novel LMX1BR246Q-mediated downregulation of WT1(−KTS) isoforms in podocytes. In conclusion, we have shown that the renal-specific phenotype associated with the LMX1BR246Q mutation may be due to a dominant negative effect on WT1(−KTS) isoforms that may cause a disruption of the WT1 (−KTS):(+KTS) isoform ratio and a decrease in the expression of podocyte genes. Full delineation of the LMX1B gene regulon is needed to define its role in maintenance of glomerular filtration barrier integrity. [ABSTRACT FROM AUTHOR]