Association between temperature and mortality: a multi-city time series study in Sichuan Basin, southwest China.

BACKGROUND: There are few multi-city studies on the association between temperature and mortality in basin climates. This study was based on the Sichuan Basin in southwest China to assess the association of basin temperature with non-accidental mortality in the population and with the temperature-related mortality burden. METHODS: Daily mortality data, meteorological and air pollution data were collected for four cities in the Sichuan Basin of southwest China. We used a two-stage time-series analysis to quantify the association between temperature and non-accidental mortality in each city, and a multivariate meta-analysis was performed to obtain the overall cumulative risk. The attributable fractions (AFs) were calculated to access the mortality burden attributable to non-optimal temperature. Additionally, we performed a stratified analyses by gender, age group, education level, and marital status. RESULTS: A total of 751,930 non-accidental deaths were collected in our study. Overall, 10.16% of non-accidental deaths could be attributed to non-optimal temperatures. A majority of temperature-related non-accidental deaths were caused by low temperature, accounting for 9.10% (95% eCI: 5.50%, 12.19%), and heat effects accounted for only 1.06% (95% eCI: 0.76%, 1.33%). The mortality burden attributable to non-optimal temperatures was higher among those under 65 years old, females, those with a low education level, and those with an alternative marriage status. CONCLUSIONS: Our study suggested that a significant association between non-optimal temperature and non-accidental mortality. Those under 65 years old, females, and those with a low educational level or alternative marriage status had the highest attributable burden.

Single-Cell RNA Sequencing Reveals Unique Alterations in the Immune Panorama and Treg Subpopulations in Mice during the Late Stages of Echinococcus granulosus Infection.

Cystic echinococcosis (CE) is a common zoonotic parasitic disease that seriously impacts public health. However, the full spectrum of immune cell changes in Echinococcus granulosus infection, especially the negative immune regulation of subpopulations of regulatory T (Treg) cells, are not yet well understood. In this study, we used single-cell RNA sequencing and immunome repertoire (IR) sequencing to analyze 53,298 cells from the spleens and peripheral blood mononuclear cells (PBMCs) of healthy and E. granulosus-infected mice. We used immunofluorescence combined with RNA fluorescence in situ hybridization and quantitative real-time PCR to verify the sequencing results. Our results showed tissue-specific immune system alterations in mice infected with E. granulosus. E. granulosus-infected mice induced a subpopulation of CD4+ cells with type I interferon production potential. Furthermore, there were six different Treg cell subpopulations in vivo at three stages of differentiation, and Treg subpopulations of different classes and different stages of differentiation showed tissue specificity. After infection, the Lag3hi Treg and Gpr83+Igfbp4+ naive Treg subpopulations were specifically induced in PBMCs and the spleen, respectively. Furthermore, T follicular helper 2 (Tfh2) cells with high expression of Cxxc5 and Spock2 were found in E. granulosus-infected mice. Our data uncovered changes in the full spectrum of immune cells in mice following the late stages of E. granulosus infection, including subpopulations of cells that have not been emphasized in previous studies. These results further enrich the study of the bidirectional immunomodulatory mechanism and offer a different perspective for subsequent studies of infection in E. granulosus.

Effects of ambient temperature on mortality among elderly residents of Chengdu city in Southwest China, 2016-2020: a distributed-lag non-linear time series analysis.

BACKGROUND: With complex changes in the global climate, it is critical to understand how ambient temperature affects health, especially in China. We aimed to assess the effects of temperature on daily mortality, including total non-accidental, cardiovascular disease (CVD), respiratory disease, cerebrovascular disease, and ischemic heart disease (IHD) mortality between 2016 and 2020 in Chengdu, China. METHODS: We obtained daily temperature and mortality data for the period 2016-2020. A Poisson regression model combined with a distributed-lag nonlinear model was used to examine the association between temperature and daily mortality. We investigated the effects of individual characteristics by sex, age, education level, and marital status. RESULTS: We found significant non-linear effects of temperature on total non-accidental, CVD, respiratory, cerebrovascular, and IHD mortality. Heat effects were immediate and lasted for 0-3 days, whereas cold effects persisted for 7-10 days. The relative risks associated with extreme high temperatures (99th percentile of temperature, 28 °C) over lags of 0-3 days were 1.22 (95% confidence interval [CI]: 1.17, 1.28) for total non-accidental mortality, 1.40 (95% CI: 1.30, 1.50) for CVD morality, 1.34 (95% CI: 1.24, 1.46) for respiratory morality, 1.33 (95% CI: 1.20, 1.47) for cerebrovascular mortality, and 1.38 (95% CI: 1.20, 1.58) for IHD mortality. The relative risks associated with extreme cold temperature (1st percentile of temperature, 3.0 °C) over lags of 0-14 days were 1.32 (95% CI: 1.19, 1.46) for total mortality, 1.45 (95% CI: 1.24, 1.68) for CVD morality, 1.28 (95% CI: 1.09, 1.50) for respiratory morality, 1.36 (95% CI: 1.09, 1.70) for cerebrovascular mortality, and 1.26 (95% CI: 0.95, 1.68) for IHD morality. We found that hot and cold affects were greater in those over 85 years of age, and that women, individuals with low education levels, and those who were widowed, divorced, or never married, were more vulnerable. CONCLUSIONS: This study showed that exposure to hot and cold temperatures in Chengdu was associated with increased mortality, with people over 85 years old, women, those with low education levels, and unmarried individuals being more affected by hot and cold temperatures.

Impacts of exposure to humidex on cardiovascular mortality: a multi-city study in Southwest China.

BACKGROUND: Many studies have reported the association between ambient temperature and mortality from cardiovascular disease (CVD). However, the health effects of humidity are still unclear, much less the combined effects of temperature and humidity. In this study, we used humidex to quantify the effect of temperature and humidity combined on CVD mortality. METHODS: Daily meteorological, air pollution, and CVD mortality data were collected in four cities in southwest China. We used a distributed lag non-linear model (DLNM) in the first stage to assess the exposure-response association between humidex and city-specific CVD mortality. A multivariate meta-analysis was conducted in the second stage to pool these effects at the overall level. To evaluate the mortality burden of high and low humidex, we determined the attributable fraction (AF). According to the abovementioned processes, stratified analyses were conducted based on various demographic factors. RESULTS: Humidex and the CVD exposure-response curve showed an inverted "J" shape, the minimum mortality humidex (MMH) was 31.7 (77th percentile), and the cumulative relative risk (CRR) was 2.27 (95% confidence interval [CI], 1.76-2.91). At extremely high and low humidex, CRRs were 1.19 (95% CI, 0.98-1.44) and 2.52 (95% CI, 1.88-3.38), respectively. The burden of CVD mortality attributed to non-optimal humidex was 21.59% (95% empirical CI [eCI], 18.12-24.59%), most of which was due to low humidex, with an AF of 20.16% (95% eCI, 16.72-23.23%). CONCLUSIONS: Low humidex could significantly increase the risk of CVD mortality, and vulnerability to humidex differed across populations with different demographic characteristics. The elderly (> 64 years old), unmarried people, and those with a limited level of education (1-9 years) were especially susceptible to low humidex. Therefore, humidex is appropriate as a predictor in a CVD early-warning system.

[Status and related factors on knowledge, attitude and practice of adults environmental health in four cities in 2021].

OBJECTIVE: To investigate the current situation and related factors of adults environmental health knowledge-attitude-practice(KAP)in four cities. METHODS: From March to April 2021, 1252 permanent residents in Mianyang City, Ya'an City in Sichuan Province, Suzhou City and Yangzhou City in Jiangsu Province were investigated on environmental health KAP by using a self-made electronic questionnaire. Analysis of variance, multiple linear regression and Person rank correlation were used to analyze the difference of public environmental KAP level, related factors, and the correlation of knowledge, attitude and behavior scores. RESULTS: There were significant differences in the level of environmental health KAP among people in different cities(F=47.632, P<0.001), age group(F=34.676, P<0.001), education level(F=49.574, P<0.001), BMI(F=4.560, P=0.003), total annual family income(F=27.977, P<0.001), smoking status(t=11.121, P=0.001)and ways of ingesting environmental health knowledge(F=88.405, P<0.001), and except BMI, other items were the related factors of environmental health KAP. The score of environmental health attitude was higher than that of behavior and knowledge(F=154.34, P<0.001). The scores of knowledge and behavior, knowledge and attitude, attitude and behavior were correlated, and the correlation coefficients were 0.667, 0.414 and 0.450 respectively(P<0.01). CONCLUSION: The number of ways to acquire environmental health knowledge, total annual family income, education level, age and smoking status are all related factors of the adults environmental knowledge-attitude-practice level in four cities in 2021.

External quality assessment for detection of methylated Syndecan 2 (SDC2) in China.

OBJECTIVES: Detection of Syndecan 2 (SDC2) methylation in stool DNA is a novel method for the auxiliary diagnosis of early colorectal cancer (CRC). Currently, this method has been widely applied; however, its accuracy and reliability have not been determined. The objective of this pioneering study was to evaluate the performance of clinical laboratories in China for their ability to detect SDC2 methylation from stool DNA. METHODS: We generated a sample panel consisting of clinical and cell samples. The clinical samples were stool specimens from patients with or without CRC, including four positives (prepared by serial dilution from one stool specimen), one negative and one interferential sample. Two cell samples, with positive or negative methylated SDC2, were used as controls. The panel was distributed to 32 clinical laboratories for analysis of SDC2 methylation, and the results were compared and scored. RESULTS: The sample panel was compatible with commercially available assays and it showed appropriate stability to be an external quality assessment material. There were four false results; one hospital laboratory and one commercial diagnostic laboratory had a false-positive and a false-negative result, respectively, and one commercial diagnostic laboratory had both a false-positive and false-negative result. Among the 32 participating laboratories, 29 (90.62%) obtained an acceptable or better performance score, while 3 (9.38%) laboratories required improvement. CONCLUSIONS: Our results demonstrate that the detection of SDC2 methylation from stool DNA was satisfactory in China. Additionally, the importance of external quality assessment was highlighted for monitoring the performance of clinical laboratories.

Effects of short-term exposure to ambient airborne pollutants on COPD-related mortality among the elderly residents of Chengdu city in Southwest China.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) has become a severe global burden in terms of both health and the economy. Few studies, however, have thoroughly assessed the influence of air pollution on COPD-related mortality among elderly people in developing areas in the hinterland of southwestern China. This study is the first to examine the association between short-term exposure to ambient airborne pollutants and COPD-related mortality among elderly people in the central Sichuan Basin of southwestern China. METHODS: Data on COPD-related mortality among elderly people aged 60 and older were obtained from the Population Death Information Registration and Management System (PDIRMS). Data on airborne pollutants comprised of particulate matter < 2.5 µm in aerodynamic diameter (PM2.5), sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3) were derived from 23 municipal environmental monitoring sites. Data on weather conditions, including daily mean temperature and relative humidity, were obtained from the Chengdu Meteorological Bureau. All data were collected from January 1, 2015, to December 31, 2018. A quasi-Poisson general additive model (GAM) was utilized to assess the effects of short-term exposure to airborne pollutants on COPD-related mortality among elderly people. RESULTS: A total of 61,058 COPD-related deaths of people aged 60 and older were obtained. Controlling the influences of daily temperature and relative humidity, interquartile range (IQR) concentration increases of PM2.5 (43 µg/m3), SO2 (8 µg/m3), NO2 (18 µg/m3), CO (0.4 mg/m3), and O3 (78 µg/m3) were associated with 2.7% (95% CI 1.0-4.4%), 4.3% (95% CI 2.1-6.4%), 3.6% (95% CI 1.7-5.6%), 2.7% (95% CI 0.6-4.8%), and 7.4% (95% CI 3.6-11.3%) increases in COPD-related mortality in people aged 60 and older, respectively. The exposure-response curves between each pollutant and the log-relative risk of COPD-related mortality exhibited linear relationships. Statistically significant differences in the associations between pollutants and COPD-related mortality were not observed among sociodemographic factors including age, gender, and marital status. The effects of O3 remained steady after adjusting for PM2.5, SO2, NO2, and CO each time in the two-pollutant models. CONCLUSIONS: Increased concentrations of ambient airborne pollutants composed of PM2.5, SO2, NO2, O3, and CO were significantly and positively associated with COPD-related mortality in the central Sichuan Basin, which is located in the hinterland of southwestern China. The adverse effects of O3 were stable, a finding that should receive more attention.

MALAT1 affects hypoxia-induced vascular endothelial cell injury and autophagy by regulating miR-19b-3p/HIF-1α axis.

Cardiovascular disease has become the leading cause of death in the world. Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) plays an important role in cardiovascular disease, such as stroke. However, the role of MALAT1 in hypoxia (HYP)-induced vascular endothelial cells (VECs) remains unclear. In the present study, HYP-treated human umbilical vein endothelial cells (HUVECs) were utilized to simulate HYP-induced VEC injury. It was found that after HYP treatment, the levels of MALAT1 and hypoxia-induced factor-1 (HIF-1α) in HUVECs were upregulated, while the level of miR-19b-3p was downregulated. Knockdown of MALAT1 with siRNA significantly reduced the HIF-1α level induced by HYP. In addition, MALAT1 knockdown inhibited HYP-induced HUVECs apoptosis, autophagy and inflammation. The overexpression of HIF-1α overcame the effect of MALAT1 knockdown. Mechanism analysis showed that MALAT1-targeted miR-19b-3p and then regulated downstream HIF-1α. MALAT1 knockdown increased the level of miR-19b-3p in cells, and increased miR-19b-3p further inhibited the expression of HIF-1α, thereby reducing the HYP-induced HUVECs apoptosis, autophagy and inflammation. Taken together, these results suggest that MALAT1 may be a potential target for mitigating HYP-induced endothelial cell injury.

Myeloid-derived suppressor cells exert immunosuppressive function on the T helper 2 in mice infected with Echinococcus granulosus.

Cystic echinococcosis (CE) is a worldwide hazardous zoonotic parasitosis caused by Echinococcus granulosus. CE development involves complex immunological mechanisms, including participation of multiple immune cells and effector molecules. Myeloid-derived suppressor cells (MDSCs) are known to be involved in chronic and acute inflammatory conditions. In this study, we aimed to characterize the immune function of MDSCs in CE to improve the understanding, prevention and treatment of CE. Our results indicated that MDSCs overexpressing Ly6C and Ly6G inhibit the formation and activity of T helper 2 cells in a NO-dependent manner during E. granulosus infection.

Associations between short-term exposure to gaseous pollutants and pulmonary heart disease-related mortality among elderly people in Chengdu, China.

BACKGROUND: Pulmonary heart disease (PHD) has become a global burden, especially in low- and middle-income countries. However, very few studies have assessed the influence of air pollution on PHD. This is the first study to explore the association between gaseous pollutants and PHD-related mortality in the central Sichuan Basin of southwestern China. METHODS: Data on PHD-related mortality among elderly people (aged 60 and older) from 2013 to 2017 were collected from the Population Death Information Registration and Management System (PDIRMS). Data on air pollutants were collected from all 24 Municipal Environmental Monitoring Sites in Chengdu, and data on daily temperature, relative humidity, and atmospheric pressure were collected from the Chengdu Municipal Meteorological Bureau. An epidemiological design of time-stratified case-crossover was conducted to assess the association between short-term exposure to ambient gaseous pollutants and PHD-related mortality among elderly people. RESULTS: About 54,920 PHD-related deaths among people aged 60 and older were reported. After controlling for daily temperature, relative humidity, and atmospheric pressure, an IQR concentration increase in levels of sulfur dioxide (SO2) (13 µg/m3), nitrogen dioxide (NO2) (17 µg/m3), and ozone (O3) (74 µg/m3) was associated with 7.8, 6.2, and 5.5% increases in PHD-related mortality in people aged 60 and older, respectively. People over age 70 might have even higher susceptibility to PHD-related mortality associated with SO2, NO2, and O3. Females and individuals with alternative marital statuses (widowed, divorced, or never married) had twice and more than twice the PHD-related mortality risk associated with SO2 and NO2 than males and married individuals, respectively. CONCLUSIONS: Increased concentrations of ambient SO2, NO2, and O3 were significantly and positively associated with PHD-related mortality in Chengdu, China. Sociodemographic factors - including gender, age, and marital status - may modify the acute health effects of gaseous pollutants.

Proteomic Analysis on Exosomes Derived from Patients' Sera Infected with Echinococcus granulosus.

Cystic echinococcosis (CE), a zoonotic disease caused by Echinococcus granulosus at the larval stage, predominantly develops in the liver and lungs of intermediate hosts and eventually results in organ malfunction or even death. The interaction between E. granulosus and human body is incompletely understood. Exosomes are nanosized particles ubiquitously present in human body fluids. Exosomes carry biomolecules that facilitate communication between cells. To the best of our knowledge, the role of exosomes in patients with CE is not reported. Here, we isolated exosomes from the sera of patients with CE (CE-exo) and healthy donors and subjected them to liquid chromatography-tandem mass spectrometry analysis. Proteomic analysis identified 49 proteins specifically expressed in CE-exo, including 4 proteins of parasitic origin. The most valuable parasitic proteins included tubulin alpha-1C chain and histone H4. And 8 proteins were differentially regulated in CE-exo (fold change>1.5), as analyzed with bioinformatic methods such as annotation and functional enrichment analyses. These findings may improve our understanding about the interaction between E. granulosus and human body, and may contribute to the diagnosis and prevention of CE.

Association between gaseous pollutants and emergency ambulance dispatches for asthma in Chengdu, China: a time-stratified case-crossover study.

OBJECTIVES: The association between concentrations of sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), ozone (O3), and emergency ambulance dispatches (EADs) for asthma was explored in the central Sichuan Basin of southwestern China for the first time. METHODS: EADs for asthma were collected from the Chengdu First-Aid Command Center. Pollutant concentrations were collected from 24 municipal environmental monitoring centers and including SO2, NO2, CO, daily 8-h mean concentrations of O3 (O3-8 h), and particulate matter less than 2.5 µm in aerodynamic diameter (PM2.5). The climatic data were collected from the Chengdu Municipal Meteorological Bureau. All data were collected from years spanning 2013-2017. A time-stratified case-crossover design was used to analyze the data. RESULTS: After controlling for temperature, relative humidity, and atmospheric pressure, IQR increases in SO2 (13 µg/m3), NO2 (17 µg/m3), and CO (498 µg/m3) were associated with 18.8%, 11.5%, and 3.1% increases in EADs for asthma, respectively. The associations were strongest for EADs and SO2, NO2, and CO levels with 3-, 5-, and 1-day lags, respectively. CONCLUSIONS: This study provides additional data to the limited body of literature for potential health risks arising from ambient gaseous pollutants. The results of the study suggest that increased concentrations of SO2, NO2, and CO were positively associated with emergency ambulance dispatches for asthma in Chengdu, China. Further studies are needed to investigate the effects of individual air pollutants on asthma.

α-Lipoic acid protects against the oxidative stress and cytotoxicity induced by cadmium in HepG2 cells through regenerating glutathione regulated by glutamate-cysteine ligase.

Alpha-lipoic acid (α-LA) is an important antioxidant that is capable of regenerating other antioxidants, such as glutathione (GSH). In the present study, we examined the protective effects of α-LA against the oxidative stress and cytotoxicity induced by cadmium in human hepatoma cell lines (HepG2) and investigated if the process was mediated through regenerating GSH. Our results showed that after exposure to 25 µM cadmium for 16 h, there was a significant decrease in the cell viability and glutathione levels and a significant increase in lipid peroxidation (p<0.01) compared with untreated cells. The presence of α-LA significantly attenuated cadmium-induced cytotoxicity and lipid peroxidation, and reversed cellular GSH levels compared with cadmium-treated cells (p<0.05). Compared with the cells treated with cadmium, co-treatment with α-LA and cadmium significantly increased the activities of γ-glutamylcysteine ligase (γ-GCL), the rate limiting enzyme in GSH biosynthesis and the mRNA and the protein levels of γ-GCL catalytic subunit (GCLC) and a modifier subunit (GCLM). In conclusion, our results indicated that α-LA is an effective agent to reduce the oxidative stress and cytotoxicity induced by cadmium by regenerating GSH levels through increasing the activities and the expressions of γ-GCL.

Assessing threshold values for eutrophication management using Bayesian method in Yuqiao Reservoir, North China.

The eutrophication problem of drinking water source is directly related to the security of urban water supplication, and phosphorus has been proved as an important element to the water quality of the most northern hemisphere lakes and reservoirs. In the paper, 15-year monitoring records (1990∼2004) of Yuqiao Reservoir were used to model the changing trend of the total phosphorus (TP), analyze the uncertainty of nutrient parameters, and estimate the threshold of eutrophication management at a specific water quality goal by the application of Bayesian method through chemical material balance (CMB) model. The results revealed that Yuqiao Reservoir was a P-controlled water ecosystem, and the inner concentration of TP in the reservoir was significantly correlated with TP loading concentration, hydraulic retention coefficient, and bottom water dissolved oxygen concentration. In the case, the goal of water quality for TP in the reservoir was set to be 0.05 mg L(-1) (the third level of national surface water standard for reservoirs according to GB3838-2002), management measures could be taken to improve water quality in reservoir through controlling the highest inflow phosphorus concentration (0.15∼0.21 mg L(-1)) and the lowest DO concentration (3.76∼5.59 mg L(-1)) to the threshold. Inverse method was applied to evaluate the joint manage measures, and the results revealed that it was a valuable measure to avoid eutrophication by controlling lowest dissolved oxygen concentration and adjusting the inflow and outflow of reservoir.

External quality assessment for the molecular detection of microsatellite instability in China, 2021-2022.

BACKGROUND: Microsatellite instability (MSI) analysis of tumors informs Lynch syndrome testing, therapeutic choice, and prognosis. The status of MSI is mainly detected by polymerase chain reaction coupled with capillary electrophoresis. However, there are various assays with different detection loci and the obtained results may vary. The objective of this study was to evaluate the concordance among different assays and the performance among different laboratories. METHODS: External quality assessment (EQA) for the detection of MSI was performed in 2021 and 2022. Each sample panel consisted of five samples, including microsatellite-stable and MSI tumor tissues. The sample panels were coded at random, and the returned results were compared and scored. RESULTS: The fully validated sample panels showed appropriate applicability with commercially available assays. There were eight false-negative results in 2021 and five false results (two false-positives and three false-negatives) in 2022. Among the participating laboratories, in 2021, 20 (74.07%) provided completely correct results; in 2022, 38 (92.68%) obtained an optimal score. CONCLUSION: The molecular detection of MSI in China exhibited an improvement in a 2-year EQA study. Participation in EQA program is an efficient way of assessing the performance of laboratories and improving their ability.

Ser252Asn Mutation Introduces a New N-Linked Glycosylation Site and Causes Type IIb Protein C Deficiency.

BACKGROUND: Protein C (PC) is a vitamin K-dependent anticoagulant serine protease zymogen which upon activation by the thrombin-thrombomodulin (TM) complex downregulates the coagulation cascade by degrading cofactors Va and VIIIa by limited proteolysis. We identified a thrombosis patient who carried a heterozygous mutation c.881G > A, p.Ser252Asn (S252N) in PROC. This mutation was originally described in a report of novel mutations in patients presenting with defective PC anticoagulant activity in Paris. The research identified PC-S252N (the "Paris" mutation) in a propositus and her family members and highlighted the critical role of Ser252 in the anticoagulation process of activated PC (APC). MATERIAL AND METHODS: We expressed the PC-S252N mutant in mammalian cells and characterized the properties in coagulation assays to decipher the molecular basis of anticoagulant defect of this mutation. RESULTS: We demonstrated that PC-S252N had a diminished ability to TM binding, which resulted in its impaired activation by the thrombin-TM complex. However, APC-S252N exhibited a slightly stronger cleavage capacity for the chromogenic substrate. Meanwhile, the catalytic activity of APC-S252N toward FVa was significantly reduced. Sequence analysis revealed that Ser252 to Asn substitution introduced a new potential N-linked glycosylation site (252NTT254) in the catalytic domain of PC, which adversely affected both the activation process of PC and anticoagulant activity of APC. CONCLUSION: The new N-glycosylation site (252NTT254) resulting from the mutation of Ser252 to Asn252 in PROC affects the overall structure of the protease, thereby adversely affecting the anticoagulant function of protein C. This modification has a negative impact on both TM-promoted activation of protein C and APC cleavage of FVa, ultimately leading to thrombosis in the patient.

Polyethylenimine functionalized magnetic nanoparticles as a potential non-viral vector for gene delivery.

Polyethylenimine (PEI) functionalized magnetic nanoparticles were synthesized as a potential non-viral vector for gene delivery. The nanoparticles could provide the magnetic-targeting, and the cationic polymer PEI could condense DNA and avoid in vitro barriers. The magnetic nanoparticles were characterized by Fourier transform infrared spectroscopy, X-ray powder diffraction, dynamic light scattering measurements, transmission electron microscopy, vibrating sample magnetometer and atomic force microscopy. Agarose gel electrophoresis was used to asses DNA binding and perform a DNase I protection assay. The Alamar blue assay was used to evaluate negative effects on the metabolic activity of cells incubated with PEI modified magnetic nanoparticles and their complexes with DNA both in the presence or absence of an external magnetic field. Flow cytometry and fluorescent microscopy were also performed to investigate the transfection efficiency of the DNA-loaded magnetic nanoparticles in A549 and B16-F10 tumor cells with (+M) or without (-M) the magnetic field. The in vitro transfection efficiency of magnetic nanoparticles was improved obviously in a permanent magnetic field. Therefore, the magnetic nanoparticles show considerable potential as nanocarriers for gene delivery.

The Mechanism of Delayed Ischemic Preconditioning in Alleviating Acute Ischemia/Reperfusion Renal Injury through Treg Mediated by Immature CD11c+ Dendritic Cells.

Introduction: Renal ischemia-reperfusion injury (IRI) is one of the major causes of acute kidney injury, and its mechanism is complex involving multiple factors, while delayed ischemic preconditioning (DIPC) has a protective effect on the above process. In our previous study, we found that DIPC can exert its protection on renal IRI by inhibiting the maturation of dendritic cells (DCs), but the mechanism has not been clarified. This study aimed to investigate the protective mechanism of DIPC on renal IRI in mice through Treg mediated by immature DCs (imDCs). Methods: The IRI mice model, DIPC treatment, and conditional CD11c+ DCs (CD11c-DTR) knockout mice were used to perform our study. The maturation and differentiation of DCs and Treg cells in the kidney and spleen were analyzed by flow cytometry. HE staining was used to evaluate the pathology of the kidney tissue. The level of creatinine (Cr), oxidative stress factors (SOD, MDA), and inflammatory factors (TNF-α, IL-10, IL-4) were also measured. Then, imDCs were co-cultured with HK-2 cells, and apoptosis was analyzed with flow cytometry and PI-Hoechst 33,342 fluorescence staining to assess the apoptosis rate of HK-2 cells under hypoxic-reoxygenated (H/R) conditions. Results: DIPC could decrease renal Cr levels, alleviate pathological renal damage, and reduce oxidative stress and inflammation caused by IRI. Moreover, DIPC could decrease the number of mature DCs (mDCs) and increase Treg lymphocyte infiltration in the kidney tissue, while the reduction of DCs reversed this process. In addition, our in vitro experiment found that in the H/R model, the apoptosis of HK-2 cells decreased which were co-cultured with imDCs. Conclusion: DIPC can regulate the differentiation of DCs into imDCs, thus affecting the differentiation level and distribution of Treg cells to exert its protective effect on renal IRI.

Proteomic Analysis of Plasma-Derived Extracellular Vesicles From Mice With Echinococcus granulosus at Different Infection Stages and Their Immunomodulatory Functions.

The globally distributed cystic echinococcosis (CE) is caused by the larval stage of Echinococcus granulosus (E. granulosus), a cosmopolitan and zoonotic disease with potentially life-threatening complications in humans. The emerging roles for extracellular vesicles (EVs) in parasitic infection include transferring proteins and modifying host cell gene expression to modulate host immune responses. Few studies focused on the host-derived EVs and its protein profiles. We focused on the EVs from mouse infected with E. granulosus at different stages. ExoQuick kit was used for isolating EVs from mouse plasma and ExoEasy Maxi kit was used for isolating protoscolex culture supernatant (PCS) and hydatid cyst fluid (HCF). Firstly, EVs were characterized by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA) and immunoblot. Secondly, the proteins of plasma EVs were identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The resulting LC-MS/MS data were processed using Maxquant search engine (v 1.5.2.8). Tandem mass spectra were researched against the mice and E. granulosus proteins database in the NCBI. The differentially expressed proteins are performed by proteomic label-free quantitative analysis and bioinformatics. Thirdly, in vitro experiment, the results of co-culture of plasma EVs and spleen mononuclear cells showed that 7W-EVs can increase the relative abundance of regulatory T (Treg) cells and IL-10. We further verified that EVs can be internalized by CD4+ and CD8+ T cells, B cells, and myeloid-derived suppressor cells (MDSC). These results implied host-derived EVs are multidirectional immune modulators. The findings can contribute to a better understanding of the role of host-derived EVs which are the optimal vehicle to transfer important cargo into host immune system. In addition, we have found several important proteins associated with E. granulosus and identified in infected mouse plasma at different stages. Furthermore, our study further highlighted the proteomics and immunological function of EVs from mouse infected with E. granulosus protoscoleces at different infection stages. We have laid a solid foundation for the role of EVs in cystic echinococcosis in the future research and supplemented a unique dataset for this E. granulosus.