Contamination status and molecular typing of Legionella pneumophila in artificial water environment in Shanghai hospitals from 2019 to 2020

BackgroundThe incidence of Legionnaires' disease is increasing globally and artificial water environment is becoming a common source of outbreaks. Molecular typing techniques can help prevent and control Legionella. ObjectiveTo understand the molecular epidemiological characteristics of Legionella pneumophila in artificial water environment of Shanghai hospitals, and provide a scientific basis for the prevention and control of Legionnaires' disease. MethodsWater samples were collected from artificial water environment in 14 hospitals from May to October each year from 2019 to 2020 in Shanghai. A total of 984 water samples were collected from 8 Grade-A tertiary hospitals and 6 non-Grade-A tertiary hospitals, including 312 samples of cooling water, 72 samples of chilled water, and 600 samples of tap water. The water samples were isolated and serotyped for Legionella pneumophila and preserved, and the positive rate of Legionella pneumophila in the samples was used as an indicator of contamination. The preserved strains were resuscitated and 81 surviving strains were obtained for pulsed field gel electrophoresis (PFGE) typing analysis. ResultsA total of 124 Legionella pneumophila positive water samples were detected, with a positive rate of 12.60%. The positive rate was higher in the Grade-A tertiary hospitals (16.54%, 87/526) than in the non-Grade-A tertiary hospitals (8.08%, 37/458) (χ2=15.91, P<0.001). The positive rate of cooling water (23.40%) was the highest among different types of water samples, and the difference was statistically significant (χ2=61.19, P<0.001). The difference in positive rate of tap water was statistically significant among different hospital departments (χ2=11.37, P<0.05). The positive rate in 2019 (15.06%) was higher than that in 2020 (9.84%) (χ2=6.23, P<0.05). From May to October, August had the highest annual average positive rate (16.46%) and October had the lowest (8.54%), but the difference in positive rates among months was not statistically significant (χ2=5.39, P=0.37). The difference in positive rate among districts was statistically significant (χ2=24.88, P<0.001). A total of 131 strains of Legionella pneumophila were isolated, with serotype 1 (80.15%, 105/131) predominating. Among the 81 surviving strains of Legionella pneumophila subjected to PFGE typing, the band-based similarity coefficients ranged from 41.30% to 100%. Among the 29 PFGE band types (S1-S29) recorded, each band type included 1-10 strains, and S28 was the dominant band type. Four clusters (I-IV) of PFGE band types were identified, accounting for 66.67% (54/81) of all strains and containing 13 band types. ConclusionLegionella pneumophila contamination is present in the artificial water environment of hospitals in Shanghai from 2019 to 2020, and the contamination in tap water deserves attention. The detected serotype of Legionella pneumophila is predominantly type 1, and PFGE typing reveals the presence of genetic polymorphism. Therefore, the monitoring and control of Legionella pneumophila in hospital artificial water environment should be strengthened

Intestinal BMP-9 locally upregulates FGF19 and is down-regulated in obese patients with diabetes

believed to be mainly produced in the liver. The serum levels of BMP-9 were reported to be reduced in newly diagnosed diabetic patients and BMP-9 overexpression ameliorated steatosis in the high fat diet-induced obesity mouse model. Furthermore, injection of BMP-9 in mice enhanced expression of fibroblast growth factor (FGF)21. However, whether BMP-9 also regulates the expression of the related FGF19 is not clear. Because both FGF21 and 19 were described to protect the liver from steatosis, we have further investigated the role of BMP-9 in this context. We first analyzed BMP-9 levels in the serum of streptozotocin (STZ)-induced diabetic rats (a model of type I diabetes) and confirmed that BMP-9 serum levels decrease during diabetes. Microarray analyses of RNA samples from hepatic and intestinal tissue from BMP-9 KO- and wild-type mice (C57/Bl6 background) pointed to basal expression of BMP-9 in both organs and revealed a down-regulation of hepatic Fgf21 and intestinal Fgf19 in the KO mice. Next, we analyzed BMP-9 levels in a cohort of obese patients with or without diabetes. Serum BMP-9 levels did not correlate with diabetes, but hepatic BMP-9 mRNA expression negatively correlated with steatosis in those patients that did not yet develop diabetes. Likewise, hepatic BMP-9 expression also negatively correlated with serum LPS levels. In situ hybridization analyses confirmed intestinal BMP-9 expression. Intestinal (but not hepatic) BMP-9 mRNA levels were decreased with diabetes and positively correlated with intestinal E-Cadherin expression. In vitro studies using organoids demonstrated that BMP-9 directly induces FGF19 in gut but not hepatocyte organoids, whereas no evidence of a direct induction of hepatic FGF21 by BMP-9 was found. Consistent with the in vitro data, a correlation between intestinal BMP-9 and FGF19 mRNA expression was seen in the patients’ samples. In summary, our data confirm that BMP-9 is involved in diabetes development in humans and in the control of the FGF-axis. More importantly, our data imply that not only hepatic but also intestinal BMP-9 associates with diabetes and steatosis development and controls FGF19 expression. The data support the conclusion that increased levels of BMP-9 would most likely be beneficial under pre-steatotic conditions, making supplementation of BMP-9 an interesting new approach for future therapies aiming at prevention of the development of a metabolic syndrome and liver steatosis

Landscape ecological risk analysis of subtropical vulnerable mountainous areas from a spatiotemporal perspective: Insights from the Nanling Mountains of China

Although mountains provide various important ecological services for human beings, the need remains to be stressed for further research on conducting ecological risk analysis in vulnerable mountainous regions characterized by a relatively high population density. In this study, the Nanling Mountains, which are recognized as a significant mountainous region in southern China, were selected as a case. Using the Globe Land30 dataset and landscape metrics, we calculated landscape ecological risk indices from 2000 to 2020. Our objective was to investigate the distribution and changes in landscape ecological risks within mountainous areas and their associated implication, to support the protection and development of the Nanling Mountains, and to provide a valuable reference case for risk management in other mountainous regions. The results showed that the land cover transformation in Nanling was predominantly driven by the expansion of artificial surfaces and open water, accompanied by a decline in woodland, cultivated land, grassland, wetland, and shrubland areas. The overall landscape metrics exhibited minimal changes, with the majority of modifications observed between 2000 and 2010. During this period, there was a noticeable shift in patch shape from complex to simple, a decrease in landscape continuity, an increase in landscape separation, and an overall increase in landscape heterogeneity. The landscape ecological risk index displayed substantial spatial heterogeneity within the study area. High-risk and medium–high-risk areas were primarily concentrated in the central and eastern regions, surrounded by medium-risk areas. Low-risk and medium–low-risk areas were widely dispersed across the entire study area. Between 2000 and 2020, there was an observed rise in the percentage of low and medium–low-risk areas from 61.74% to 64.05%. This indicates an overall enhancement in the ecological environment of the study area. The transfer of landscape ecological risk primarily involved artificial surfaces and high-altitude grasslands. The correlation analysis between the total regional GDP and LERI showed that there was a smooth inverse “U” linear relationship between them. To conclude, there exists a definite correlation between the landscape ecological risk and human activities, particularly environmental policies. Additionally, the relationship between the landscape ecological risk index and the total regional GDP aligns with the Environmental Kuznets Curve. It is crucial to approach major decisions concerning densely populated and fragile mountainous areas with careful consideration and caution. In promoting land optimization and integration, priority should be given to the area around the artificial surface

Screening Study on Rheological Behavior and Phase Transition Point of Polymer-containing Fluids produced under the Oil Freezing Point Temperature

For an increasing implementation of the low-temperature transportation in oilfield, it is urgent priority initially to study the physical and chemical properties to provide the vital technical support for the low-temperature transport of the polymer flooding. In this paper, the rheological behavior of polymer-containing fluid produced from the Daqing polymer flood were first studied for an adaptation of transportation under the oil’s freezing point temperature. The experiments progressed with different temperature, shear rate, water content and polymer concentration which have great impacts on the viscosity of the fluids produced aiming to find the phase transportation point for the application of the low-temperature transportation. It was displayed that a significant discontinuity in the viscosity occurs at some range of water content. Before the phase transition point, presented in W/O (water-in-oil) emulsion, the viscosity was lifted with the increase of the water content while after the phase transition point, forming the O/W (oil-in-water) type emulsion, the viscosity was dropped with an increase of water content. The phase transition points strongly depend on the polymer concentration in the fluids Produced. It was demonstrated that the phase transition points of polymer-containing fluids were 65%, 70%, 50%, 50% and 50%, corresponding to the polymer concentrations of 315mg/L, 503mg/L, 708mg/L, 920mg/L and 1053mg/L, respectively. The characteristics are attributed to the viscous polymer. The fluidity of the fluid produced was decreased with the increase of polymer concentration

Penicillin and Cefotaxime Resistance of Quinolone-Resistant Neisseria meningitidis Clonal Complex 4821, Shanghai, China, 1965–2020

Clonal complex 4821 (CC4821) Neisseria meningitidis, usually resistant to quinolones but susceptible to penicillin and third-generation cephalosporins, is increasing worldwide. To characterize the penicillin-nonsusceptible (PenNS) meningococci, we analyzed 491 meningococci and 724 commensal Neisseria isolates in Shanghai, China, during 1965–2020. The PenNS proportion increased from 0.3% in 1965–1985 to 7.0% in 2005–2014 and to 33.3% in 2015–2020. Of the 26 PenNS meningococci, 11 (42.3%) belonged to the CC4821 cluster; all possessed mutations in penicillin-binding protein 2, mostly from commensal Neisseria. Genetic analyses and transformation identified potential donors of 6 penA alleles. Three PenNS meningococci were resistant to cefotaxime, 2 within the CC4821 cluster. With 96% of the PenNS meningococci beyond the coverage of scheduled vaccination and the cefotaxime-resistant isolates all from toddlers, quinolone-resistant CC4821 has acquired penicillin and cefotaxime resistance closely related to the internationally disseminated ceftriaxone-resistant gonococcal FC428 clone, posing a greater threat especially to young children

Evaluating the Environmental and Economic Performance of Municipal Solid Waste Disposal by All-Component Resource Recovery

Disposal of municipal solid waste (MSW) has become increasingly challenging. In this study, we used life cycle assessment (LCA) to evaluate environmental impacts and financial performance of a new approach for MSW disposals, namely All-components Resource Recovery (AcRR), which is based on automatic sorting. We compared AcRR with the standardized Waste-to-Energy incineration (WtE) to provide decision-making support for MSW management. The results show that WtE and AcRR are both good MSW resource treatment methods. Through MSW disposal, WtE generates electricity, while AcRR generates secondary resources such as metals, plastics, pulp and organic fertilizers. WtE releases trace amounts of HCl, PM10, heavy metals, dioxins and dust, while AcRR does not produce such pollutants; AcRR produces more odor gases such as SO2 and H2S. AcRR produces four environmental issues, i.e., Global Warming, Acidification, Photochemical Ozone Synthesis, and Eutrophication, each of which has a smaller impact than WtE; WtE has two more impacts than AcRR: Human Toxicity and Soot and Ashes. The total environmental impact potential of WtE is 3.38 times that of AcRR, and the greenhouse gas emission equivalent is 6.82 times that of AcRR. The cost of construction and operation of AcRR is lower than that of WtE, while the net profit of AcRR is much higher. In conclusion, AcRR is able to screen the mixed MSW into various secondary resources with less environmental emissions and environmental impacts and better financial performance; it may be a promising MSW disposal approach, especially for small cities, but a corresponding supporting industrial system is needed

Evaluating the Environmental and Economic Performance of Municipal Solid Waste Disposal by All-Component Resource Recovery

Disposal of municipal solid waste (MSW) has become increasingly challenging. In this study, we used life cycle assessment (LCA) to evaluate environmental impacts and financial performance of a new approach for MSW disposals, namely All-components Resource Recovery (AcRR), which is based on automatic sorting. We compared AcRR with the standardized Waste-to-Energy incineration (WtE) to provide decision-making support for MSW management. The results show that WtE and AcRR are both good MSW resource treatment methods. Through MSW disposal, WtE generates electricity, while AcRR generates secondary resources such as metals, plastics, pulp and organic fertilizers. WtE releases trace amounts of HCl, PM10, heavy metals, dioxins and dust, while AcRR does not produce such pollutants; AcRR produces more odor gases such as SO2 and H2S. AcRR produces four environmental issues, i.e., Global Warming, Acidification, Photochemical Ozone Synthesis, and Eutrophication, each of which has a smaller impact than WtE; WtE has two more impacts than AcRR: Human Toxicity and Soot and Ashes. The total environmental impact potential of WtE is 3.38 times that of AcRR, and the greenhouse gas emission equivalent is 6.82 times that of AcRR. The cost of construction and operation of AcRR is lower than that of WtE, while the net profit of AcRR is much higher. In conclusion, AcRR is able to screen the mixed MSW into various secondary resources with less environmental emissions and environmental impacts and better financial performance; it may be a promising MSW disposal approach, especially for small cities, but a corresponding supporting industrial system is needed

Characterizing the cellular and molecular variabilities of peripheral immune cells in healthy recipients of BBIBP-CorV inactivated SARS-CoV-2 vaccine by single-cell RNA sequencing

AbstractOver 3 billion doses of inactivated vaccines for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been administered globally. However, our understanding of the immune cell functional transcription and T cell receptor (TCR)/B cell receptor (BCR) repertoire dynamics following inactivated SARS-CoV-2 vaccination remains poorly understood. Here, we performed single-cell RNA and TCR/BCR sequencing on peripheral blood mononuclear cells at four time points after immunization with the inactivated SARS-CoV-2 vaccine BBIBP-CorV. Our analysis revealed an enrichment of monocytes, central memory CD4+ T cells, type 2 helper T cells and memory B cells following vaccination. Single-cell TCR-seq and RNA-seq comminating analysis identified a clonal expansion of CD4+ T cells (but not CD8+ T cells) following a booster vaccination that corresponded to a decrease in the TCR diversity of central memory CD4+ T cells and type 2 helper T cells. Importantly, these TCR repertoire changes and CD4+ T cell differentiation were correlated with the biased VJ gene usage of BCR and the antibody-producing function of B cells post-vaccination. Finally, we compared the functional transcription and repertoire dynamics in immune cells elicited by vaccination and SARS-CoV-2 infection to explore the immune responses under different stimuli. Our data provide novel molecular and cellular evidence for the CD4+ T cell-dependent antibody response induced by inactivated vaccine BBIBP-CorV. This information is urgently needed to develop new prevention and control strategies for SARS-CoV-2 infection. (ClinicalTrials.gov Identifier: NCT04871932).Trial registration: ClinicalTrials.gov identifier: NCT04871932.