49 research outputs found
Blood arsenic exposure levels of preschool children and dietary factors analysis
Objective To explore the blood arsenic exposure levels of preschool children and analyze the factors of blood arsenic. Methods By the multi-stage cluster and simple randomized method, six districts of Shanghai City was chosen and the preschool children in the selected village were asked to fill in the questionnaire and have blood sampling. Inductively coupled plasma mass spectrometry (ICP-MS) was used to detect blood arsenic, of which the data was analyzed by multiple linear regression models. Marine fish, freshwater fish, freshwater shrimp and shellfish were grouped as follows: ≤3 times per month, 1-3 times per week, and 4-6 times per week. Rice, noodles and milk were grouped as <50, 50-100, and ≥100 g/d. Results 2 263 preschool children were recruited. The range of blood arsenic was 0.12-27.94 μg/L. The median (P25, P75) were 2.26 (1.63, 3.09) μg/L. Statistical analysis showed that the more intake of rice, wheaten food, and sea fish and shrimp, the more arsenic in children’s blood (P<0.05). Whereas highter intake of freshwater fish and shrimp group showed decreased blood arsenic (P<0.05). Conclusion Most preschool children’s blood arsenic levels (92.4%, 2 091/2 263) were at normal level (<5 μg/L). There was a positive correlation between blood arsenic concentration and the intake of rice, wheaten food, and sea fish and shrimp, while negative correlation with high freshwater fish and shrimp consumption
Assessment of global health risk of antibiotic resistance genes
Antibiotic resistance genes (ARGs) have accelerated microbial threats to human health in the last decade. Many genes can confer resistance, but evaluating the relative health risks of ARGs is complex. Factors such as the abundance, propensity for lateral transmission and ability of ARGs to be expressed in pathogens are all important. Here, an analysis at the metagenomic level from various habitats (6 types of habitats, 4572 samples) detects 2561 ARGs that collectively conferred resistance to 24 classes of antibiotics. We quantitatively evaluate the health risk to humans, defined as the risk that ARGs will confound the clinical treatment for pathogens, of these 2561 ARGs by integrating human accessibility, mobility, pathogenicity and clinical availability. Our results demonstrate that 23.78% of the ARGs pose a health risk, especially those which confer multidrug resistance. We also calculate the antibiotic resistance risks of all samples in four main habitats, and with machine learning, successfully map the antibiotic resistance threats in global marine habitats with over 75% accuracy. Our novel method for quantitatively surveilling the health risk of ARGs will help to manage one of the most important threats to human and animal health
Construction of a Medical Micro-Object Cascade Network for Automated Segmentation of Cerebral Microbleeds in Susceptibility Weighted Imaging
Aim: The detection and segmentation of cerebral microbleeds (CMBs) images are the focus of clinical diagnosis and treatment. However, segmentation is difficult in clinical practice, and missed diagnosis may occur. Few related studies on the automated segmentation of CMB images have been performed, and we provide the most effective CMB segmentation to date using an automated segmentation system.Materials and Methods: From a research perspective, we focused on the automated segmentation of CMB targets in susceptibility weighted imaging (SWI) for the first time and then constructed a deep learning network focused on the segmentation of micro-objects. We collected and marked clinical datasets and proposed a new medical micro-object cascade network (MMOC-Net). In the first stage, U-Net was utilized to select the region of interest (ROI). In the second stage, we utilized a full-resolution network (FRN) to complete fine segmentation. We also incorporated residual atrous spatial pyramid pooling (R-ASPP) and a new joint loss function.Results: The most suitable segmentation result was achieved with a ROI size of 32 × 32. To verify the validity of each part of the method, ablation studies were performed, which showed that the best segmentation results were obtained when FRN, R-ASPP and the combined loss function were used simultaneously. Under these conditions, the obtained Dice similarity coefficient (DSC) value was 87.93% and the F2-score (F2) value was 90.69%. We also innovatively developed a visual clinical diagnosis system that can provide effective support for clinical diagnosis and treatment decisions.Conclusions: We created the MMOC-Net method to perform the automated segmentation task of CMBs in an SWI and obtained better segmentation performance; hence, this pioneering method has research significance
Optimization for the Production of Surfactin with a New Synergistic Antifungal Activity
-surfactin and the optimization of its production by the response surface method.O. A production of 134.2 mg/L, which were in agreement with the prediction, was observed in a verification experiment. In comparison to the production of original level (88.6 mg/L), a 1.52-fold increase had been obtained.-surfactin
Study on the Relationship between River Water and Groundwater under Different Aquifer Mediums
There is a strong river water–groundwater hydraulic connection, particularly in arid and semi-arid regions in which rivers are the main source of groundwater recharge. Therefore, a study of this relationship is of great practical significance. This study investigated this relationship for three kinds of homogeneous sand with different particle sizes using sandbox experiments. Consistent with previous studies, as the moisture of the sand decreased, the discharged water level continued to decline and the hydraulic connection between river water and groundwater was gradually lost. Discharged flow increased as the discharge level decreased and stabilized after reaching a maximum threshold. However, inconsistent with the results of previous studies, the thickness of the inverted saturation zone was not always equal to the river water depth. In addition, the maximum discharge flow resulting from cutting off the river and groundwater was different from that noted in previous studies. A coarse sand water-bearing medium resulted in a thickness of a suspended saturated zone of 15–20 cm, for 18.5 cm river water depth and 5–10 cm for 10 cm river water depth. The results for medium sand with a thickness of 5–10 cm (18.5 cm river water depth) was the disappearance of the suspended saturated water zone (10 cm river water depth), as it was for a fine sand thickness of 15–20 cm (18.5 cm river water depth), and a thickness of 10–15 cm (10 cm river water depth). The results indicated that the thickness of the inverted saturation zone formed by the separation of the connection between the river and the groundwater is not only related to the depth of the river, but also affected by various physical parameters of the aquifer. An empirical formula for calculating the thickness of the inverted saturation band is given based on the experimental results
Blood Lead Levels and Risk Factors among Preschool Children in a Lead Polluted Area in Taizhou, China
Objective. To determine the blood lead levels and identify related risk factors among preschool children in a lead polluted area (Taizhou, China) and provide theoretical support for prevention of lead pollution. Methods. A stratified-clustered-random sampling method was used to determine the survey sample. Blood lead levels were determined by the tungsten atomizer absorption spectrophotometer. Results. A total of 2,018 subjects (average age of 59 months; 1,087 boys and 931 girls) were included. The arithmetic mean, geometric mean, and median blood lead levels of the preschool children were 56.4 μg/L, 48.9 μg/L, and 46 μg/L. A total of 8.8% children had blood lead levels >100 μg/L and 43.9% had blood lead levels >50 μg/L. Mother’s education level, father’s occupation, decorative tableware, exposure to makeup, and the residential floor were all risk factors for elevated blood lead levels (odds ratios of 1.42, 1.21, 1.11, 1.19, and 1.27, resp.), while hand washing before eating food was a protective factor (odds ratio of 0.88). Conclusions. The blood lead levels of preschool children in Taizhou were higher than in other areas in China and in developed countries. Therefore, policies ensuring lead-based industries are not placed in close proximity to residential areas are required
THE EXPRESSION AND SIGNIFICANCE OF SERUM TRAb, TSAb, AND TSBAb IN PATIENTS WITH HASHIMOTO’S THYROIDITIS WITH HYPOTHYROIDISM
Objective To investigate the changes in serum thyrotropin receptor antibody (TRAb), thyroid stimulating antibody (TSAb), and thyroid-stimulating blocking antibody (TSBAb) and their significance in patients with Hashimoto’s thyroiditis with hypothyroidism (HT hypothyroidism). Methods A total of 133 patients with HT hypothyroidism (HT hypothyroidism group) and 125 healthy subjects (control group) were enrolled and their clinical data were collected. The serum levels of free triiodothyronine (FT3), free thyroxine (FT4), thyrotropin (TSH), and TRAb were measured and compared between the two groups. TSAb and TSBAb were also compared across the patients who were positive for TRAb (group B), who were negative for TRAb (group C), and the healthy subjects who were negative for TRAb (group A). A Pearson correlation analysis was used to examine the relationships between the serum levels of TSAb and TSBAb and the serum levels of FT3, FT4, TSH, and TRAb in patients with HT hypothyroidism. Results The serum TRAb level in the HT hypothyroidism group was significantly higher than that in the control group (Z=-5.434,P<0.05). Compared with group A, group B showed significantly higher serum levels of TRAb and TSBAb and positive rate of serum TSBAb (Z=6.228,F=17.985,t=7.767,χ2=15.273,P<0.05); compared with group C, group B had significantly higher serum levels of TRAb and TSBAb and positive rates of serum TSAb and TSBAb (Z=5.732,F=17.985,t=7.056,χ2=62.115,52.000,P<0.05). The Pearson correlation analysis showed that the serum TSBAb level in patients with HT hypothyroidism was positively correlated with their serum TRAb level (r=0.756,P<0.05). Conclusion The increased expression of TSBAb in serum may be an important factor in the pathogenesis of HT hypothyroidism. For HT hypothyroidism patients with positive serum TRAb, attention should be paid to the measurement of their serum TSBAb expression
Effects of Acupuncture on CCL2 and CXCL8 Expression and the Subset of uNK Cells in Rats with Embryo Implantation Failure
The present study was designed to investigate the efficacy and mechanism of acupuncture treatment on embryo implantation failure in rats. The pregnant rats were randomized into normal group (N), implantation failure group (M), acupuncture treatment group (A), and progestin treatment group (W). The embryo implantation failure model was established by mifepristone. Efficacy of acupuncture treatment was evaluated by the number of implanted embryos. The expression of CCL2 and CXCL8 and the subset of uterine natural killer cells in the endometrium were detected. We demonstrated that the number of implanted embryos was dramatically reduced after mifepristone (M group) treatment, while the acupuncture (A group) and progestin (W group) treatments significantly rescued impaired embryo implantation. The protein and mRNA expressions of CCL2 and CXCL8 were significantly reduced by mifepristone treatment, but the attenuated expression of CCL2 and CXCL8 was markedly reversed by acupuncture or progestin treatment. More importantly, acupuncture and progestin could markedly increase the subset of uNK cells in rats with embryo implantation failure. These evidences suggest that acupuncture is able to modulate the endometrial immune microenvironment and thus improve embryo implantation in pregnant rats, which provides solid experimental evidence for the curative effect of acupuncture treatment on infertility
Effect of PBAT Biodegradable Mulch Film Extract on Seed Germination and Seedlings Metabolism of Tobacco
Poly(butylene adipate-co-terephthalate) biodegradable mulch film (PBAT-BMF) is gradually applied in agricultural production, but its potential ecological risks have not been studied so far. In this paper, methyl tert-butyl ether (MTBE) was used to extract organic compounds from PBAT-BMF to evaluate its effects on tobacco seed germination and seedling metabolism. The results showed that six organic compounds were found in the extract of PBAT-BMF, among which the content of diisopropylphenyl isocyanate was the highest at 557.27 μg g−1. A germination test showed that the extract scan inhibited the germination of tobacco seeds. The germination time was 1 d later than the control(CK), and the germination percentage and germination energy were non-significantly decreased by 2.50% and 1.00%. In contrast, the extracts significantly affected the root length, and seedlings height (p < 0.01), decreased by 0.24 cm and 0.28 cm, respectively. A metabolic analysis revealed that the extracts have a certain stress effect on tobacco seedlings and showed an up-regulating effect on soluble sugar, critical organic acid, biogenic amine, and down-regulating alkaloid, which indicated that the carbon and nitrogen metabolism pathway of the tricarboxylic acid cycle and alkaloid synthesis were disturbed. These results indicated that organic compounds extracted from PBAT-BMF had stress effects on germination and the growth of tobacco seeds, which significantly changed the metabolism pathway. This study can provide a theoretical basis for the development and application of PBAT-BMF