The Study of Serum Vitamin D and Insulin Resistance in Chinese Populations with Normal Glucose Tolerance

Objectives. The aim of this study was to investigate the relationship between serum vitamin D and insulin resistance in Chinese subjects without diabetes mellitus. Methods. Serum 25(OH)D was measured in 897 individuals with normal glucose tolerance (NGT). Oral glucose tolerance tests (OGTTs) were conducted to exclude cases with diabetes, impaired fasting glucose (IFG), and impaired glucose tolerance (IGT). Metabolic parameters were measured and compared between the highest and lowest 25(OH)D quartiles. The relationship between serum 25(OH)D and homeostatic model assessment-insulin resistance (HOMA-IR) was analyzed. Results. Indexes, such as HOMA-IR, FINS, and SBP, were negatively correlated with serum 25(OH)D concentrations. Compared with the lowest quartile, individuals in the highest group had decreased Lg (HOMA-IR), Lg (FINS), and SBP. Pearson correlation analyses showed that serum 25(OH)D was negatively associated with age, BMI, Lg (HOMA-IR), and Lg (FINS). Multivariate linear regression analysis confirmed the negative correlation of Lg (HOMA-IR) and 25(OH)D. Conclusions. This study showed that serum 25(OH)D could be regarded as an independent predictor of insulin resistance for subjects without diabetes mellitus in China. Adequate vitamin D supplementation may improve multiple metabolic disturbances

Energy saving in metro ventilation system based on multi-factor analysis and air characteristics of piston vent

Energy saving contributes to sustainable development, and the fresh air induced by piston effect is closely related to the ventilation and energy saving of subway system. This paper is aimed at finding the optimal combination and energy conservation of metro ventilation system based on factor analysis and environment control system operation strategy. The numerical simulation and experiment are carried out in this paper. Firstly the variation trend of velocity field is reasonable by being compared with on-site experimental data. Secondly, orthogonal experimental design is adopted to study the major factors affecting the fresh air volume flowing into the station from the station entrance-exit, and then the optimal combination of energy saving is obtained. Next, the calculation results show that the annual electricity saving amount of the optimal combination is obviously greater than that of actual metro station and previous literature. To be specific, the maximal energy saving of the optimal combination is 236729 kW·h, while that of the actual metro station is merely 75888 kW·h. Namely the maximal energy saving of the optimal combination is about 3 times as large as that of the actual metro station. Finally, the energy saving of key factors is discussed in detail, and the results prove the energy saving increase is consistent with the rise of the blockage rate and the distance between the piston vent and the station. Besides, the optimal energy saving blockage ratio is 0.6 considering the actual blockage ratio and economic cost. According to the above consequences, innovative energy saving measures about the utilization of unorganized fresh air are proposed, which is applicable to typical subway station

New insight into enhanced production of short-chain fatty acids from waste activated sludge by cation exchange resin-induced hydrolysis

Recently, the production of short-chain fatty acids (SCFAs) from waste activated sludge (WAS) has received increasing attention. Although several pretreatment methods had been investigated, sludge hydrolysis through depletion of multivalent cations has rarely been reported. In this work, cation exchange resin (CER) was used for enhancing WAS hydrolysis and subsequent SCFAs production at various dosages of 0 to 3.5 g/g SS. With the addition of CER, the multivalent cations and trace metal elements (e.g. Ca2+, Mg2+, Fe3+, Zn2+, etc.) were removed from sludge through CER-mediated ion exchange, leading to disruption of extracellular polymeric substance (EPS), while triggering cell lysis which was evidenced by remarkable leakage of cellular DNA. This CER-mediated cyclic release-removal of multivalent cations resulted in substantial sludge hydrolysis with release of biodegradable organic matters. At the optimal CER dosage of 1.75 g/g SS, soluble COD (SCOD) was dramatically increased to 5944 mg/L (SCOD/TCOD = 34.7%) against 1440 mg/L in the control after 2-day fermentation. Meanwhile, a considerable SCFAs of 334.5 mg COD/g VSS was produced within the first 4 days of anaerobic fermentation, which was 3.3 times higher than that in the control. It was found that the acetic and propionic acids accounted for 57.4–65.4% of SCFAs produced in CER-assisted anaerobic fermentation. Compared to pretreatment with potassium ferrate, surfactant and enzymes, a much higher SCFAs concentration was obtained in this study with CER. In fact, used CER could be recovered and reused, without harsh chemicals left in fermented sludge. This indeed created an environmentally and economically beneficial situation with considerably saved pretreatment agents.This work was supported by the National Natural Science Foundation of China – China (No.51778179)

Enhancing volatile fatty acids production from waste activated sludge by a novel cation-exchange resin assistant strategy

This study developed a novel strategy for enhancing volatile fatty acids production from waste activated sludge by cation-exchange resin assistant anaerobic fermentation. The process condition was optimized by response surface methodology. Considerable sludge disintegration degree (40.9%) and volatile fatty acids yield (4619.6 mg COD/L) were achievable at the proposed process conditions, i.e. cation-exchange resin dosage = 2.05 and 1.78 g/g SS, fermentation time = 4.97 and 6.46 d, and stirring strength = 246.9 and 261.2 rpm, respectively. Grey relational analysis revealed that cation-exchange resin dosage, fermentation time, and stirring strength presented similarly significant effects on sludge disintegration. The reusability tests showed that NaCl solution had the best effect on cation-exchange resin regeneration, and the performance of regenerated resin was comparable with the original resin on volatile fatty acids production. Compared with conventional pretreatment methods, the proposed cation-exchange resin assistant strategy revealed obvious advantages of saved pretreatment agents, easy operation, none chemical residual in sludge and small footprint. Total volatile fatty acids recovery can reach 1.46 × 108 tons chemical oxygen demand annually in terms of China's context, which could offset one third of carbon gap in China's wastewater treatment plants. The proposed cation-exchange resin assistant strategy indeed sheds lights on the direction for WAS treatment in a close alignment with process viability and engineering feasibility.This work was supported by the National Natural Science Foundation of China e China (No.51778179) and Research and Development Program in Key Areas of Guangdong Province (2019B110209002)

Decreased Soluble Receptor of Advanced Glycation End Product Levels Correlated with Inflammation in Silicosis

Silicosis is a devastating disease caused by inhalation of silica dust that leads to inflammatory cascade and then scarring of the lung tissue. Increasing evidences indicate that soluble receptor for advanced glycation end products (sRAGE) is involved in inflammatory diseases. However, no data on the possible relationship between sRAGE and inflammation of silicosis are available. In this study, serum from subjects with silicosis (n=59) or from healthy controls (HC, n=14) was analyzed for the secretion of sRAGE, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), transforming growth factor-β1 (TGF-β1), and oxidized low-density lipoprotein (ox-LDL). The associations between sRAGE and cytokines and ox-LDL and lung function were assessed by Pearson’s correlation analyses. Mean levels of serum sRAGE were lower in silicosis than those in controls (p<0.05). The subjects who had a longer term of occupational exposure had higher levels of sRAGE (p<0.05). The secretion of TNF-α, IL-1β, IL-6, TGF-β1, and ox-LDL was significantly higher in the silicosis group than that in the HC group (p<0.05). Furthermore, the levels of sRAGE were negatively correlated with TNF-α, IL-6, IL-1β, and ox-LDL. There is no correlation between sRAGE and TGF-β1 and lung function. The optimal point of sRAGE for differentiating silicosis from healthy controls was 14250.02 pg/ml by ROC curve analysis. A decrease in serum sRAGE and its association with inflammatory response might suggest a role for sRAGE in the pathogenesis of silicosis

An innovative alkaline protease-based pretreatment approach for enhanced short-chain fatty acids production via a short-term anaerobic fermentation of waste activated sludge

This study reported a novel pretreatment approach with combination of alkaline protease (AP) and pH 10 for enhancing short-chain fatty acids (SCFAs) production from waste activated sludge (WAS). Through the AP-based pretreatment, WAS flocs were disintegrated with cell lysis, leading to release of biodegradable organic matters. At the external AP dosage of 5%, SCOD of 5363.7 mg/L (SCOD/TCOD = 32.5%) was achievable after 2-h pretreatment. More than 66% of SCOD was composed of proteins and carbohydrates. Considerable SCFAs of 607 mg COD/g VSS was produced over a short-term anaerobic fermentation of 3 days, which was 5.4 times higher than that in the control. Acetic and propionic acids accounted for 74.1% of the SCFAs. The AP-based approach increased endogenous protease and ?-glucosidase activities, facilitating biodegradation of dissolved organic matters and SCFAs production. Such approach is promising for WAS disposal and carbon recovery, the produced SCFAs might supply 60% of carbon gap in wastewater

Association between population density and infection rate suggests the importance of social distancing and travel restriction in reducing the COVID-19 pandemic

International audienceCurrently, 2019-nCoV has spread to most countries of the world. Understanding the environmental factors that affect the spreadof the disease COVID-19 infection is critical to stop the spread of the disease. The purpose of this study is to investigate whetherpopulation density is associated with the infection rate of the COVID-19. We collected data from official webpages of cities inChina and in the USA. The data were organized on Excel spreadsheets for statistical analyses. We calculated the morbidity andpopulation density of cities and regions in these two countries. We then examined the relationship between morbidity and otherfactors. Our analysis indicated that the population density in cities in Hubei province where the COVID-19 was severe wasassociated with a higher percentage of morbidity, with an r value of 0.62. Similarly, in the USA, the density of 51 states andterritories is also associated with morbidity from COVID-19 with an r value of 0.55. In contrast, as a control group, there is noassociation between the morbidity and population density in 33 other regions of China, where the COVID-19 epidemic is wellunder control. Interestingly, our study also indicated that these associations were not influenced by the first case of COVID-19.The rate of morbidity and the number of days from the first case in the USA have no association, with an r value of − 0.1288.Population density is positively associated with the percentage of patients with COVID-19 infection in the population. Our datasupport the importance of such as social distancing and travel restriction in the prevention of COVID-19 spread

Lipid Uptake by Alveolar Macrophages Drives Fibrotic Responses to Silica Dust

Abstract Silicosis is a common occupational disease and represents a significant contributor to respiratory morbidity and mortality worldwide. Lipid-laden macrophages, or foam cells, are observed in the lungs of patients with silicosis but the mechanisms mediating their formation remain poorly understood. In this study, we sought to elucidate the mechanisms by which silica promotes foam cell formation in the lung, and to determine whether uptake of lipids alone is sufficient to drive TGF-β production by alveolar macrophages. Consistent with previous reports, we found that foam cells were markedly increased in the lungs of patients with silicosis and that these findings associated with both higher levels of intracellular lipid levels (oxidized LDL, ox-LDL) and elevated transcript levels for the lipid scavenger receptor CD36 and the nuclear receptor PPARγ. Employing a rat alveolar macrophage cell line, we found that exposure to silica dust or ox-LDL alone had a modest effect on the induction of foam cell formation and only silica was capable of inducing the production of TGF-β. In contrast, foam cell formation and TGF-β production were both dramatically increased when cells were exposed to a combination of silica dust and ox-LDL. Moreover, we found that these endpoints were markedly attenuated by either blocking CD36 or inhibiting the activity of PPARγ. Altogether, our findings suggest that foam cell formation and TGF-β production are driven by the simultaneous uptake of silica and lipids in alveolar macrophages and that strategies aimed at blocking lipid uptake by alveolar macrophages might be effective in ameliorating fibrotic responses to silica in the lung

Template-Free Synthesis of Hollow/Porous Organosilica–Fe₃O₄ Hybrid Nanocapsules toward Magnetic Resonance Imaging-Guided High-Intensity Focused Ultrasound Therapy

Entirely differing from the common templating-based multistep strategy for fabricating multifunctional hollow mesoporous silica nanoparticles (HMSN), a facile and template-free synthetic strategy has been established to construct a unique hollow/mesoporous organosilica nanocapsule (OSNC) concurrently encapsulating both isopentyl acetate (PeA) liquid and superparamagnetic iron oxides inside (denoted as PeA@OSNC). This novel material exhibits ultrasmall and uniform particle size (∼82 nm), high surface area (∼534 m²·g^–1), and excellent colloidal stability in aqueous solution. The oil-phase PeA with relatively low boiling point (142 °C) and high volatility not only plays a crucial role in formation of a large hollow cavity from the viewpoint of structural design but also enables the PeA@OSNC to act as an efficient enhancement agent in high-intensity focused ultrasound (HIFU) therapy. Moreover, the unique satellite-like distribution of Fe₃O₄ nanoparticles (NP) on the organosilica shell offered excellent magnetic resonance imaging (MRI) contrast capability of PeA@OSNC in vitro and in vivo. More importantly, such a novel theranostic agent has favorable biosafety, which is very promising for future clinical application in MRI-guided HIFU therapy