How will the public health committees develop after COVID-19 pandemic in China? Exploration from mixed methods study in Pingshan District, Shenzhen.

Introduction: The Public Health Committee has a long-standing presence in the Chinese Constitution. During the pandemic, it served as a grassroots self-governance organization and made significant contributions to China's community epidemic prevention and control system. Currently, 24 provinces in China have promoted the establishment of community public health committees. Methods: To gather data, we conducted semi-structured interviews (n = 48) with the heads of superior departments of public health committees, the heads of public health committees, and the heads of community health centers, exploring aspects such as organizational structure, job responsibilities, and job security. In parallel, we administered a capacity-building survey to a sample of 23 community residents (n = 1,986) and performed regression analysis. Finally, we examined the impact of gender, age, and education level on the development of public health committees. Results: Our study reveals that the development of public health committees displays features of administration across various dimensions, including personnel appointment, top-level design, medical professionalism, funding path dependence, and data path dependence. However, the decision-making function of the organization does not exhibit a significant impact. Discussion: The construction of the Public Health Committee should demonstrate an "autonomization-administration" pendulum effect. Currently, due to the absence of decision-making functions within the Public Health Committee, autonomous organizations are exhibiting characteristics of administration. To prevent excessive autonomization or administrative nature in the development of committees, public health policies are continuously being refined based on the unique characteristics of public health committee construction. During exceptional circumstances or the initial stages of development, the establishment of public health committees should be primarily guided by administrative principles, utilizing political momentum to drive their progress. In contrast, during routine establishment phases or later stages of development, the establishment of public health committees should be primarily led by autonomization, restoring their capacity for self-decision making. It is essential to fully leverage the role of grassroots self-governance organizations, relying on the community to engage in self-management, self-education, and self-service within public health committees.

Effects of Stool Sample Preservation Methods on Gut Microbiota Biodiversity: New Original Data and Systematic Review with Meta-Analysis.

Here, we aimed to compare the effects of different preservation methods on outcomes of fecal microbiota. We evaluated the effects of different preservation methods using stool sample preservation experiments for up to 1 year. The stool samples from feces of healthy volunteers were grouped based on whether absolute ethanol was added and whether they were hypothermically preserved. Besides, we performed a systematic review to combine current fecal microbiota preservation evidence. We found that Proteobacteria changed significantly and Veillonellaceae decreased significantly in the 12th month in the room temperature + absolute ethanol group. The four cryopreservation groups have more similarities with fresh sample in the 12 months; however, different cryopreservation methods have different effects on several phyla, families, and genera. A systematic review showed that the Shannon diversity and Simpson index of samples stored in RNAlater for 1 month were not statistically significant compared with those stored immediately at -80°C (P = 0.220 and P = 0.123, respectively). The -80°C refrigerator and liquid nitrogen cryopreservation with 10% glycerine can both maintain stable microbiota of stool samples for long-term preservation. The addition of absolute ethanol to cryopreserved samples had no significant difference in the effect of preserving fecal microbial characteristics. Our study provides empirical insights into preservation details for future studies of the long-term preservation of fecal microbiota. Systematic review and meta-analysis found that the gut microbiota structure, composition, and diversity of samples preserved by storage methods, such as preservation solution, are relatively stable, which were suitable for short-term storage at room temperature. IMPORTANCE The study of gut bacteria has become increasingly popular, and fecal sample preservation methods and times need to be standardized. Here, we detail a 12-month study of fecal sample preservation, and our study provides an empirical reference about experimental details for long-term high-quality storage of fecal samples in the field of gut microbiology research. The results showed that the combination of -80°C/liquid nitrogen deep cryopreservation and 10% glycerol was the most effective method for the preservation of stool samples, which is suitable for long-term storage for at least 12 months. The addition of anhydrous ethanol to the deep cryopreserved samples did not make a significant difference in the preservation of fecal microbiological characteristics. Combined with the results of systematic reviews and meta-analyses, we believe that, when researchers preserve fecal specimens, it is essential to select the proper preservation method and time period in accordance with the goal of the study.

Effects of the bioelectrochemical technique on methane emission and energy recovery in constructed wetlands (CWs) and related biological mechanisms.

In this study, effects of bioelectrochemical technique on methane emission and energy recovery, and related mechanism underlying microbial competition were investigated. The results showed that running MFC was beneficial in reducing CH4 emissions and promoting COD removal rates, regardless of whether the plant roots were located at the anode or the cathode. CH4 emission was significantly higher in open-circuit reactors (6.2 mg m-2 h-1) than in closed-circuit reactors (3.1 mg m-2 h-1). Plant roots at the cathode had the highest electricity generation and the lowest CH4 emissions. The highest power generation (0.49 V, 0.33 w m-3) and the lowest CH4 emissions (2.3 mg m-2 h-1) were observed in the reactors where Typha orientalis was planted with plant roots at the cathode. The role of plants in strengthening electron acceptor was greater than that of plant rhizodeposits in strengthening electron donors. Real-time quantitative PCR (q-PCR) and correlation analysis indicated that the mcrA genes and CH4 emissions were positively correlated (r = 0.98, p < 0.01), while no significant relationship between CH4 emissions and pmoA genes was observed. Illumina sequencing revealed that more abundant exoelectrogens and denitrifying bacteria were observed when plant roots were located in cathodes. Strictly acetotrophic archae (Methanosaetaceae) were likely the main electron donor competitors with exoelectrogens. The results showed that the location of both plant species and plant roots at the electrode played an important role in CH4 control and electricity generation. Therefore, it is necessary to strengthen plant configuration to reduce CH4 emissions, to promote sustainable development of wastewater treatment.

Impacts of Social Participation on Self-Rated Health of Aging Women in China: With a Mediating Role of Caring for Grandchildren.

Population aging is a global challenge and the degree of population aging is continuing to deepen in China. Under the active aging policy framework by WHO, great importance has been attached to aging women and participation is emphasized for the well-being of the elderly. This study aimed to investigate the relation between social participation and self-rated health status of aging women in China and whether caring for grandchildren mediated such an association. Adopting data from the 2018 China Health and Retirement Longitudinal Study (CHARLS), this study used Oprobit regression, propensity score matching (PSM), and instrument variable regression to estimate the effects. The result showed that there was a positive association between social participation and self-rated health among aging women in China, and social activities that directly made contributions to others had the most significant impacts on self-rated health. Furthermore, the mediator analysis confirmed that caring for grandchildren played a role between social participation and self-rated health. In conclusion, to deal with population aging challenges, the society should recognize the value of intergenerational care for aging women and the government need to strengthen policy supports to guarantee platforms and opportunities for the elderly to participate in social activities.

The role and related microbial processes of Mn-dependent anaerobic methane oxidation in reducing methane emissions from constructed wetland-microbial fuel cell.

Anaerobic oxidation of methane (AOM) plays an important role in global carbon cycle and greenhouse gas emission reduction. In this study, an effective green technology to reduce methane emissions was proposed by introducing Mn-dependent anaerobic oxidation of methane (Mn-AOM) and microbial fuel cell (MFC) technology into constructed wetland (CW). The results indicate that the combination of biological methods and bioelectrochemical methods can more effectively control the methane emission from CW than the reported methods. The role of dissimilated metal reduction in methane control in CW and the biochemical process associated with Mn-AOM were also investigated. The results demonstrated that using Mn ore as the matrix and operating MFC effectively reduced methane emissions from CW, and higher COD removal rate was obtained in CW-MFC (Mn) during the 200 days of operation. Methane emission from CW-MFC (Mn) (53.76 mg/m2/h) was 55.61% lower than that of CW (121.12 mg/m2/h). The highest COD removal rate (99.85%) in CW-MFC (Mn) was obtained. As the dissimilative metal-reducing microorganisms, Geobacter (5.10%) was found enriched in CW-MFC (Mn). The results also showed that the presence of Mn ore was beneficial to the biodiversity of CW-MFCs and the growth of electrochemically active bacteria (EAB) including Proteobacteria (35.32%), Actinobacteria (2.38%) and Acidobacteria (2.06%), while the growth of hydrogenotrophic methanogens Methanobacterium was effectively inhibited. This study proposed an effective way to reduce methane from CW. It also provided reference for low carbon technology of wastewater treatment.

Biochemical pathways and enhanced degradation of dioctyl phthalate (DEHP) by sodium alginate immobilization in MBR system.

As one of the most representative endocrine disrupting compounds, dioctyl phthalate (DEHP) is difficult to remove due to its bio-refractory characteristic. In this study, an immobilization technology was applied in an MBR system to improve the degradation of DEHP. The degradation efficiency of DEHP was significantly improved and the number of degradation genes increased by 1/3. A bacterial strain that could effectively degrade DEHP was isolated from activated sludge and identified as Bacillus sp. The degradation pathway of DEHP was analyzed by GC-MS. DEHP was decomposed into phthalates (DBP) and Diuretic sylycol (DEP), then further to Phthalic acid (PA). PA was oxidized, dehydrogenated, and decarboxylated into protocatechins, further entered the TCA cycle through orthotopic ring opening. The DEHP degrading strain was immobilized by sodium alginate and calcium chloride under the optimized immobilization conditions, and added to MBR systems. The removal rate of DEHP (5 mg/L) (91.9%) and the number of 3, 4-dioxygenase gene copies was significantly improved by adding immobilized bacteria. Micromonospora, Rhodococcus, Bacteroides and Pseudomonas were the dominant genuses, and the results of bacterial community structure analysis show that immobilization technology is beneficial to system stability. The results showed the potential applications of the immobilized technique in DEHP wastewater treatment in MBR.

Aerobic biodegradation pathways of pentabromobiphenyl ethers (BDE-99) and enhanced degradation in membrane bioreactor system.

A bacterial strain capable of efficiently degrading pentabromobiphenyl ether (BDE-99) was isolated from activated sludge and named as NLPSJ-22. This strain was highly close to Pseudomonas asplenii with 100% similarity. The degradation products of BDE-99 were analyzed by gas chromatography mass spectrometry. The biochemical degradation pathways analysis indicated that BDE-99 gradually transformed to diphenyl ether by meta-, para- and ortho-debromination. It became phenol under the action of ring-opening cracking and finally entered the tricarboxylic acid cycle. The degradation of BDE-99 by strain NLPSJ-22 conformed to the first-order reaction kinetics. Rhamnolipid significantly improved the cell-surface hydrophobicity and the degradation of BDE-99. The highest degradation efficiency (96%) was achieved when diphenyl ether as co-metabolic substrate was added. In the bioaugmentation membrane bioreactor (MBR) system, BDE-99 was intensively degraded, and the reactor reached a steady state in about 35 days. The degradation rate of BDE-99 was over 80%, which was significantly higher than that of the control system. MiSeq sequencing results indicated that the genera of Rhodococcus, Bacillus, Pseudomonas, Burkholderia, and Sphingobium were the predominant bacterial communities responsible for BDE-99 biodegradation in the MBR. Pseudomonas increased significantly in the bioaugmented reactor with the relative abundance increasing from 5% to 24%.

CH4 control and associated microbial process from constructed wetland (CW) by microbial fuel cells (MFC).

Global warming is becoming more severe. We here proposed an innovative green technique aimed at reducing the CH4 emissions from constructed wetlands (CWs) in which CH4 is controlled by microbial fuel cells (MFCs). The results of our work indicated that CH4 emissions from CWs could be controlled by operating MFC. The CH4 fluxes significantly decreased in the MFC-CW (close circuit CC) compared with the control MFC-CW (open circuit OC). The bioelectricity generation and COD removal rates also differed in the two systems. The highest power density (0.27 W m-3) and the lowest CH4 emissions (4.7 mg m-2 h-1) were observed in the CC system. The plants' effects on the performance of the MFC-CWs were also investigated. The plant species had a profound impact on the CH4 emissions and electricity production in MFC-CWs. The greatest CH4 flux (9.5 mg m-2 h-1) was observed from the MFC-CW planted with Typha orientalis, while the CH4 emissions from the MFC-CW planted with Cyperus alternifolius were reduced by 45%. Additional microbial processes were investigated. Quantitative real-time PCR (q-PCR) analysis indicated that the gene abundance of eubacterial 16 S rRNA, particulate methane monooxygenase (pmoA), and methyl coenzyme M reductase (mcrA) significantly differed for the control CW and MFC-CWs planted with different plants. In the CC systems, the mcrA genes in the anode were low, while the pmoA genes in the cathode were high. The operation of MFCs in CWs changed the exoelectrogenic and methanogenic community structures. Sequencing analysis indicated that phylotypes related to Geobacter, Bacteroides, and Desulfovibrio were specifically enriched in the CC systems. The results demonstrated that the operation of MFCs in the CWs resulted in the competition between the electrogenes and methanogenes, which resulted in distinctive microbial populations and biochemical processes that suppressed the CH4 emissions from the CWs.

Dexamethasone impairs the differentiation and maturation of murine dendritic cells by Toll-like receptor 4-nuclear factor-kappaB pathway.

BACKGROUND: Recent studies have demonstrated that dexamethasone (DEX) interferes with immune responses by targeting key functions of dendritic cells (DCs) at the earliest stage. However, the cellular and molecular mechanisms are still incompletely understood. This study aimed to explore the possible mechanisms by investigating the roles of DEX on differentiation, maturation & function of murine DCs and the effects of DEX on DCs via Toll-like receptor 4 (TLR4)-nuclear factor (NF)-kappaB mediated signal pathway. METHODS: Immature DCs (imDCs) were cultured from murine bone marrow (BM) cells. We added DEX into culture medium at different time. The expression of CD11c, CD86 and I-A(b) (mouse MHC class II molecule) was determined by flow cytometry. We determined the expression of NF-kappaB and its inhibitory protein I-kappaBalpha by electrophoretic mobility shift assay (EMSA) and Western blotting, respectively. The productions of interleukin (IL)-12p70 and IL-10 in cell culture supernatants were determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: DEX impaired differentiation of DCs from murine bone marrow progenitors, and inhibited lipopolysaccharide (LPS) induced maturation of DCs. DEX significantly inhibited NF-kappaB expression of normal DCs, the higher the DEX concentration or the longer the DEX treatment time, the more obvious the effect. However, DEX had little effect on LPS-induced NF-kappaB activation, and partially impaired LPS-induced I-kappaBalpha degradation. DEX significantly decreased LPS induced IL-12p70 production by DCs. Interestingly, our results showed a synergistic effect between DEX and LPS on the production of IL-10 by DCs. CONCLUSIONS: DEX inhibits the differentiation and maturation of murine DCs involved in TLR4-I-kappaB-NF-kappaB pathway, and also indirectly impairs Th1 development and interferes with the Th1-Th2 balance through IL-12 and/or IL-10 secretion by DCs.

[Prokaryotic expression of S2 extracellular domain of SARS coronavirus spike protein and its fusion with Hela cell membrane].

OBJECTIVE: To construct the expression plasmid of S2 extracellular domain (S2ED) of SARS-coronavirus (SARS- Cov) spike protein (S protein) and enhanced green fluorescent protein (EGFP) to obtain the fusion protein expressed in prokaryotic cells. METHODS: S2ED based on bioinformatics prediction and EGFP sequence were amplified by PCR and inserted into pET-14b plasmid. The recombinant protein His-S2ED-EGFP was expressed in E. coli by IPTG induction. After purification by Ni-NTA agarose beads, the soluble fractions of the fusion protein were collected and identified by SDS-PAGE and Western blotting. The fusion of S2ED with Hela cell membranes was observed with fluorescent microscope. RESULTS: The pET-14b-S2ED-EGFP plasmid was correctly constructed and highly expressed in BL21 (DE3). When incubated with Hela cells, the purified protein could not internalize through membrane fusion. CONCLUSIONS: The expression plasmid containing S2ED of SARS-Cov S protein and EGFP sequence is constructed successfully. Although the recombinant protein obtained has not shown the expected fusion effect with Hela cell membrane, this work may enrich the understanding of the process of membrane fusion mediated by S2 protein and lay the foundation for future study of targeting cell transport system based on cell-specific binding peptide.

[The analysis in the expression of Toll-like receptor 4 mRNA and the effect of dexamethasone on mice dendritic cells by real-time PCR].

AIM: To establish a SYBR Green I quantitative real-time PCR method for detecting the expression of the TLR4 mRNA of mice and to monitor the dynamics for TLR4 mRNA level of mice bone marrow-derived dendritic cells (DC) in the process of the maturation and the effect of dexamethasone (DEX) on TLR4 expression. METHODS: (1) DC from mice bone marrow were induced by cytokines and separated by magnetic beads. (2) The combined plasmid pUCm-T/TLR4 and pUCm-T/beta-actin for the standard materials in the real-time PCR was reconstructed. (3) The dynamics for the express TLR4 mRNA of DC cultivated in vitro for 4, 6, 8, 10, 12 days was detected respectively. (4) The TLR4 mRNA expression between DC treated with or without DEX was detected and compared. RESULTS: (1) The DC with the purity over 90% were fully separated in success. (2) A SYBR Green I quantitative real-time PCR method for analyzing the TLR4 mRNA expression level of the mice was successful established. (3) TLR4 mRNA level was stable early during the culture of DC and then rise obviously at last. CONCLUSION: There exists a close relationship between the level of TLR4 mRNA and the period of maturation of DC and the expression of TLR4 could be increased by DEX.