24 research outputs found
Contamination and health risk assessment of heavy metals in road dust in Bayan Obo Mining Region in Inner Mongolia, North China
Heavy metals in different moss species in alpine ecosystems of Mountain Gongga, China: Geochemical characteristics and controlling factors
Terrestrial mosses are promising tracers for research concerning metal atmospheric deposition and pollution. Concentrations of Cr, Co, Ni, Zn, Sr, Cd, Ba, and Pb in different moss species from Mountain Gongga, China were analyzed to investigate the effects of growth substrates, geographic elevation, and type of moss species on the accumulation characteristics of heavy metals, as well as to identify heavy metal sources. The ability of heavy metals to accumulate in moss varied significantly, with low concentrations of Cd and Co; medium concentrations of Cr, Ni, and Pb; and high concentrations of Zn, Sr, and Ba. Elevation significantly influenced the accumulation characteristics of heavy metals, with high concentrations found at lower elevations due to proximal pollution. Growth substrate and moss species were found to have certain influence on the bioconcentration capacities of heavy metals in moss in this study. Correlation analysis showed similar sources for Sr, Zn, and Ba, as well as for Ni, Co, and Cr. The positive matrix factorization (PMF) model was consistent with atmospheric deposition of Pb and Cd; substrate sources of Cr, Co, and Ni; and anthropogenic sources of Ba, Sr, and Zn. This research characterized the accumulation characteristics of heavy metals and their influence factors in different mosses found in alpine ecosystems and provides a reference for future studies in similar areas. (C) 2020 Elsevier Ltd. All rights reserved
Mycobacterium Tuberculosis-Specific TNF-α Is a Potential Biomarker for the Rapid Diagnosis of Active Tuberculosis Disease in Chinese Population
<div><p>Interferon-gamma release assays (IGRAs) have proven to be useful to accurately detect <i>Mycobacterium tuberculosis</i> (<i>Mtb</i>) infection, but they cannot reliably discriminate between active tuberculosis (TB) and latent tuberculosis infection (LTBI). This study aims to test whether <i>Mtb</i>-specific tumor necrosis factor-alpha (TNF-α) could be used as a new tool for the rapid diagnosis of active TB disease. The secretion of TNF-α by <i>Mtb</i>-specific antigen-stimulated peripheral blood mononuclear cells (PBMCs) of sixty seven participants was investigated in the study. Our results showed that the total measurement of TNF-α secretion by <i>Mtb</i>-specific antigen-stimulated PBMCs is not a good biomarker for active TB diagnosis. However, we found that calculation of <i>Mtb</i>-specific TNF-α not only distinguish between active and latent TB infection, but also can differentiate active TB from non-TB patients. Using the cutoff value of 136.9 pg/ml for <i>Mtb</i>-specific TNF-α, we were able to differentiate active TB from LTBI. Sensitivity and specificity were 72% and 90.91%. These data suggest that <i>Mtb</i>-specific TNF-α could be a potential biomarker for the diagnosis of active TB disease.</p></div
Measurement of Coupling Coordination Degree and Spatio-Temporal Characteristics of the Social Economy and Ecological Environment in the ChengduâChongqing Urban Agglomeration under High-Quality Development
With rapid urbanization and industrialization, ecological disorders and environmental degradation have become serious, and the promotion of the coordinated development of the social economy and ecological environment is not only a pressing problem to be solved, but also an important step towards sustainable development. The coordinated development of the social economy and eco-environment is conducive to sustainable development. Considering the ChengduâChongqing urban agglomeration as a case study, this paper adopts panel data and establishes an index system to evaluate the coupling coordination degree (CCD) between the social economy and ecological environment based on the concept of high-quality development. From the perspective of time and space, the changing laws and characteristics of the CCD are analyzed, and the key factors affecting it are determined using regression analysis. The results show the following: (1) the CCD between the social economy and ecological environment of the ChengduâChongqing urban agglomeration presents a low level overall; (2) the CCD in more developed regions is significantly higher than that in less developed regions; thus, the characteristics of spatial differences are obvious; (3) the urbanization rate, ratio of actual use of foreign capital and GDP, ratio of total export-import volume and GDP, proportion of days with good air quality, and per capita public green space area are the main factors affecting the coordinated development of the social economy and ecological environment in the ChengduâChongqing urban agglomeration; and (4) Chongqing has obvious endogeneity. Finally, corresponding policy recommendations are provided aimed at promoting rapid economic development in the ChengduâChongqing urban agglomeration while focusing on environmental protection and promoting high-quality economic development with ecological environmental protection, while putting forward decision-making suggestions for high-quality development of urban agglomerations
The secretions of TNF-α and <i>Mtb</i>-specific TNF-α by ESAT-6 or CFP-10-stimulated PBMCs.
<p>PBMCs obtained from active TB patients (nâ=â25), LTBI individuals (nâ=â22), healthy control subjects (nâ=â10) and non-TB patients (nâ=â10) were stimulated with ESAT-6 or CFP-10. PBMCs stimulated with medium alone were used as a background control. (A) After 16â20 h of incubation, the supernatant was collected and tested for concentrations of secreted TNF-α by ELISA. (B) <i>Mtb</i>-specific TNF-α was calculated by subtracting background TNF-α secreted by medium-stimulated PBMCs from TNF-α secreted by ESAT-6 or CFP-10-stimulated PBMCs. Median values for each group of participants are represented by a horizontal bar. *<i>p</i> < 0.05, **<i>p</i> < 0.001.</p
Statistical analysis of ROC curve for <i>Mtb</i>-specific TNF-α to distinguish between active TB and LTBI.
<p>Note. TB: tuberculosis; LTBI: latent tuberculosis infection; AUC: area under the curve.</p
The cytotoxicity of ESAT-6 to PHA-stimulated PBMCs of three non-TB patients.
<p>Note. PHA: phytohemagglutinin; TB: tuberculosis; AFS: acid fast staining.</p
GSTM1 and GSTT1 null polymorphisms and childhood acute leukemia risk: evidence from 26 case-control studies.
Several molecular epidemiological studies have been conducted to examine the association between glutathione S-transferase mu-1 (GSTM1) and glutathione S-transferase theta-1 (GSTT1) null polymorphisms and childhood acute leukemia; however, the conclusions remain controversial. We performed an extensive meta-analysis on 26 published case-control studies with a total of 3252 cases and 5024 controls. Crude odds ratios (ORs) with 95% confidence interval were used to assess the strength of association between childhood acute leukemia risk and polymorphisms of GSTM1 and GSTT1. With respect to GSTM1 polymorphism, significantly increased risk of childhood acute leukemia was observed in the overall analysis (OR = 1.30; 95%CI, 1.11-1.51). Furthermore, a stratification analysis showed that the risk of GSTM1 polymorphism are associated with childhood acute leukemia in group of Asians (OR = 1.94; 95%CI, 1.53-2.46), Blacks (OR = 1.76; 95%CI, 1.07-2.91), ALL (OR = 1.33; 95%CI, 1.13-1.58), '< 100 cases and <100 controls' (OR = 1.79; 95%CI, 1.21-2.64), 'â„ 100 cases and â„ 100 controls' (OR = 1.25; 95%CI, 1.02-1.52), and population-based control source (OR = 1.40; 95%CI, 1.15-1.69). With respect to GSTT1 polymorphism, significant association with childhood acute leukemia risk was only found in subgroup of Asian. This meta-analysis supports that GSTM1 null polymorphism is capable of causing childhood acute leukemia susceptibility
Light-Induced Cell Alignment and Harvest for Anisotropic Cell Sheet Technology
Well-organized
orientation of cells and anisotropic extracellular matrix (ECM) are
crucial in engineering biomimetic tissues, such as muscles, arteries,
and nervous system, and so on. This strategy, however, is only beginning
to be explored. Here, we demonstrated a light-induced cell alignment
and harvest for anisotropic cell sheets (ACS) technology using light-responsive
TiO<sub>2</sub> nanodots film (TNF) and photo-cross-linkable gelatin
methacrylate (GelMA). Cell initial behaviors on TNF might be controlled
by micropatterns of light-induced distinct surface hydroxyl features,
owing to a sensing mechanism of myosin II-driven retraction of lamellipodia.
Further light treatment allowed ACS detachment from TNF surface while
simultaneously solidified the GelMA, realizing the automatic transference
of ACS. Moreover, two detached ACS were successfully stacked into
a 3D bilayer construct with controllable orientation of individual
layer and maintained cell alignment for more than 7 days. Interestingly,
the anisotropic HFF-1 cell sheets could further induce the HUVECs
to form anisotropic capillary-like networks via upregulating VEGFA
and ANGPT1 and producing anisotropic ECM. This developed integrated-functional
ACS technology therefore provides a novel route to produce complex
tissue constructs with well-defined orientations and may have a profound
impact on regenerative medicine