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1.
BMC Public Health ; 24(1): 1009, 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38605341

ABSTRACT

INTRODUCTION: Few studies focused on the Pre-Exposure Prophylaxis (PrEP) -related aspects, and the applicability of prior evidence to young men who have sex with men (YMSM) students was unknown. This study aimed to assess the awareness, willingness, uptake, and adherence (AWUA) to PrEP among YMSM students in China and to explore the associated factors with these stages. METHODS: A cross-sectional survey with a sizable sample of 1151 was conducted among YMSM students aged 16 and above, who self-identified as men who have sex with men(MSM) and resided in mainland China between October 20 and December 20, 2021. The chi-square test and Fisher's exact test were used for univariate analysis, followed by multivariable logistic regression analysis of influencing factors at all levels. RESULTS: According to the cascade analysis approach, 88.71% of the participants were aware of PrEP, among which 66.7% expressed willingness to use it. Among those who were willing to use PrEP, only 13.80% took it, and of those who took it, 44.68% adhered to it. The students taking PrEP were those with higher education (OR = 4.239, 95% CI: 1.334-13.467), residence in pilot cities (OR = 2.791, 95% CI: 1.498-5.198), residence in high-risk areas (OR = 5.082, 95% CI: 2.224-11.612), engagement in multi-person sexual behavior (OR = 2.186, 95% CI: 1.236-3.867), and substance use (OR = 1.908, 95% CI: 1.167-3.118). Furtherly, students with higher adherence to PrEP were likely to have receptive sexual behaviors (OR = 8.702, 95% CI: 2.070-36.592), absence of substance use (OR = 4.468, 95% CI: 1.371-14.561), and uptake of PrEP through daily oral route. (OR = 7.065, 95% CI: 1.699-29.371). CONCLUSION: YMSM students exhibit distinct patterns of "high awareness, low willingness, low uptake, and low adherence" to PrEP. Strategies for reduction in the acquisition of HIV prioritizing the current features of utilizing PrEP were urgently warranted.


Subject(s)
HIV Infections , Pre-Exposure Prophylaxis , Sexual and Gender Minorities , Substance-Related Disorders , Male , Humans , Homosexuality, Male , Cross-Sectional Studies , HIV Infections/epidemiology , HIV Infections/prevention & control , China/epidemiology
2.
HIV Med ; 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38533603

ABSTRACT

INTRODUCTION: In China, young men who have sex with men (YMSM) are one of the groups most at risk of HIV/AIDS. The uptake of pre-exposure prophylaxis (PrEP) among YMSM has not been well documented. A cascade analysis of awareness, willingness, use and adherence with regard to PrEP was conducted separately among YMSM students and non-students. METHODS: From 20 October to 30 December 2021, all adolescents aged 16-24 years were selected for the study from among MSM recruited from 31 provincial administrative regions in mainland China. Participants were included in a cross-sectional study of awareness, willingness, use and adherence with regard to PrEP among YMSM. Logistic regression modelling was used to identify factors associated with the four outcomes. RESULTS: Among 1014 student and 866 non-student YMSMs, respectively, 88.07% and 81.64% had heard of PrEP; 58.16% and 50.35% were willing to use PrEP; 7.59% and 7.62% had used PrEP; and 3.16% and 3.58% had adhered to PrEP. Among students, those living in high-risk areas and pilot cities and those who had engaged in commercial sex and group sex had a positive effect on PrEP use, and the same trends were found among non-students living in high-risk areas and pilot cities and those who had engaged in group sex. 'Daily oral' and 'flexible' PrEP use positively influenced adherence among both groups. CONCLUSIONS: A differentiation strategy of PrEP promotion should be implemented among YMSM. Material support for students, such as financial resources, should increase, while non-students should increase their level of perception of HIV risk.

3.
Per Med ; 20(6): 503-510, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37909375

ABSTRACT

Background: Genetic polymorphism can affect the response to antiviral therapy of chronic hepatitis B (CHB) patients. Objective: The study examined the genetic association of the IL-6 rs1800796 polymorphism with PEGylated IFN-α (PegIFN-α) treatment response in hepatitis B surface antigen (HBsAg)-positive CHB patients. Methods: Direct sequencing was done for the genotyping of the rs1800796 polymorphism in the serum of CHB patients. Results: More patients with combined response (n = 95) carried IL-6 rs1800796 GC genotypes, while CC genotype carriers possessed reduced HBeAg seroconversion rate and high values of hepatitis B virus DNA. Baseline HBsAg and HBeAg and IL-6 rs1800796 CC genotype were independently related to PegIFN-α treatment response. Conclusion: Detection of the IL-6 rs1800796 genotype in CHB patients may have potential guiding significance for PegIFN-α response.


Subject(s)
Hepatitis B Surface Antigens , Hepatitis B, Chronic , Humans , Hepatitis B Surface Antigens/genetics , Hepatitis B Surface Antigens/therapeutic use , Antiviral Agents/therapeutic use , Interleukin-6/genetics , Interleukin-6/therapeutic use , Hepatitis B e Antigens/genetics , Hepatitis B e Antigens/therapeutic use , Hepatitis B, Chronic/drug therapy , Hepatitis B, Chronic/genetics , Treatment Outcome , Interferon-alpha/therapeutic use , Polymorphism, Genetic , Polyethylene Glycols/therapeutic use
4.
Micromachines (Basel) ; 14(8)2023 Jul 31.
Article in English | MEDLINE | ID: mdl-37630075

ABSTRACT

The performance of supercapacitors is directly influenced by the conductivity of polypyrrole, which serves as the electrode material. In order to balance considerations of cost-effectiveness and conductivity, this study employs magnetron sputtering to fabricate a copper-tin alloy layer as the conductive layer for polypyrrole. The deposition of a copper-tin alloy film through magnetron sputtering has a significant impact on the polymerization effect of pyrrole as well as being a crucial factor influencing the performance of supercapacitors. Various parameters, including working pressure, sputtering time, and sputtering power, affect the conductivity of the copper-tin alloy film. Furthermore, the degree of influence of each parameter on the conductivity of the copper-tin alloy film varies. This study utilizes an orthogonal experimental design to investigate the impact of various factors and levels on the conductivity and uniformity of a metal film. The objective is to optimize the process parameters for the creation of a copper-tin alloy film with desirable characteristics. Experimental results indicate that the working voltage, sputtering time, and sputtering power significantly influence the coefficient of variation, deposition rate, target current, and operating voltage of the film. Furthermore, FT-IR, XRD, and SEM tests are conducted on samples prepared using the identified optimal process parameters. In addition, we demonstrate various approaches to enhance the experiment's reliability. The findings indicate that the most favorable process parameters for achieving optimal results are a working pressure of 0.065 Pa, a sputtering time of 20 min, and a sputtering power of 70 W. It was observed that the sputtering time significantly influences the uniformity of the copper-tin alloy film, whereas the sputtering power has a minimal impact on its uniformity. The deposition rate is primarily influenced by the working pressure, with the greatest effect observed. Conversely, the sputtering time has the least impact on the deposition rate. Similarly, the target current is predominantly affected by the sputtering power, exhibiting the greatest influence, while the sputtering time has the least effect. Furthermore, the working voltage is most significantly influenced by the working pressure, whereas the sputtering time has the least impact on the working voltage.

5.
Front Microbiol ; 14: 1206038, 2023.
Article in English | MEDLINE | ID: mdl-37426000

ABSTRACT

Introduction: Duck circovirus (DuCV) infection is currently recognized as an important immunosuppressive disease in commercial duck flocks in China. Specific antibodies against DuCV viral proteins are required to improve diagnostic assays and understand the pathogenesis of DuCV infection. Methods and results: To generate DuCV-specific monoclonal antibodies (mAbs), a recombinant DuCV capsid protein without the first 36 N-terminal amino acids was produced in Escherichia coli. Using the recombinant protein as an immunogen, a mAb was developed that reacted specifically with the DuCV capsid protein, expressed in E. coli and baculovirus systems. Using homology modeling and recombinant truncated capsid proteins, the antibody-binding epitope was mapped within the region of 144IDKDGQIV151, which is exposed to solvent in the virion capsid model structure. To assess the applicability of the mAb to probe the native virus antigen, the murine macrophage cell line RAW267.4 was tested for DuCV replicative permissiveness. Immunofluorescence and Western blot analysis revealed that the mAb recognized the virus in infected cells and the viral antigen in tissue samples collected from clinically infected ducks. Discussion: This mAb, combined with the in vitro culturing method, would have widespread applications in diagnosing and investigating DuCV pathogenesis.

6.
Micromachines (Basel) ; 14(6)2023 May 29.
Article in English | MEDLINE | ID: mdl-37374733

ABSTRACT

In this paper, a 3D printing system for a thermal battery electrode ink film is set up and investigated based on the on-demand microdroplet ejection technology. The optimal structural dimensions of the spray chamber and metal membrane of the micronozzle are determined via simulation analysis. The workflow and functional requirements of the printing system are set up. The printing system includes a pretreatment system, piezoelectric micronozzle, motion control system, piezoelectric drive system, sealing system, and liquid conveying system. Different printing parameters are compared to obtain optimized printing parameters, which can be attributed to the optimal pattern of the film. The feasibility and controllability of 3D printing methods are verified by printing tests. The size and output speed of the droplets can be controlled by adjusting the amplitude and frequency of the driving waveform acting on the piezoelectric actuator. So, the required shape and thickness of the film can be achieved. An ink film in terms of nozzle diameter = 0.6 mm, printing height = 8 mm, wiring width = 1 mm, input voltage = 3 V and square wave signal frequency = 35 Hz can be achieved. The electrochemical performance of thin-film electrodes is crucial in thermal batteries. The voltage of the thermal battery reaches its peak and tends to flatten out at around 100 s when using this printed film. The electrical performance of the thermal batteries using the printed thin films is found to be stable. This stabilized voltage makes it applicable to thermal batteries.

7.
Tohoku J Exp Med ; 261(1): 13-23, 2023 Sep 12.
Article in English | MEDLINE | ID: mdl-36792178

ABSTRACT

Gastric cancer is a common malignant tumor with a relatively poor prognosis after surgery. Non-coding RNA may serve as biomarkers for the progression and prognosis of various cancers. The clinical significance and biological function of lncRNA TRHDE-AS1 and miR-1275 in gastric cancer were assessed in this study. 119 paired tissues were selected with adequate clinical information. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to determine the expression level of lncRNA TRHDE-AS1 and miR-1275 in gastric cancer tissues and cells. The association between lncRNA TRHDE-AS1 or miR-1275 expression and the clinicopathological features of patients was analyzed by the Pearson Chi-square test. Kaplan-Meier analysis and Multi-variate Cox proportional regression analysis were utilized to evaluate the prognostic value of lncRNA TRHDE-AS1 and miR-1275. Finally, the effect of TRHDE-AS1 binding to miR-1275 on the gastric cancer cellular process was investigated by CCK-8 and Transwell assay. LncRNA TRHDE-AS1 was found to be downregulated in gastric cancer tissues and cells, but miR-1275 upregulated, which both showed significant associations with clinical pathology of gastric cancer patients (including TNM stage and lymph node metastasis) and a poor prognosis. LncRNA TRHDE-AS1 and miR-1275 can be considered two independent prognostic factors for gastric cancer. Furthermore, the upregulation of lncRNA TRHDE-AS1 inhibited cell proliferation, migration, and invasion of gastric cancer partly by miR-1275. LncRNA TRHDE-AS1/miR-1275 axis may be involved in the progression of gastric cancer and can be promising prognostic factors, which may provide new insights into the treatment of gastric cancer.


Subject(s)
MicroRNAs , RNA, Long Noncoding , Stomach Neoplasms , Humans , Stomach Neoplasms/genetics , Stomach Neoplasms/pathology , MicroRNAs/genetics , Prognosis , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Biomarkers , Cell Proliferation/genetics , Cell Line, Tumor , Gene Expression Regulation, Neoplastic , Cell Movement/genetics
8.
Appl Opt ; 62(3): 714-719, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36821276

ABSTRACT

The dual-wavelength paired-pulse output of a compact self-Q-switched T m:Y A l O 3 intra-cavity pumping H o:L u L i F 4 laser was first demonstrated experimentally. By exploiting the self-Q-switching mechanism of T m:Y A l O 3 and the gain-switching operation of H o:L u L i F 4 in a cavity, the dual-wavelength paired pulses were robustly generated with the pulse energy of 29 µJ, pulse width of 2.5 µs at 1944 nm, pulse energy of 31 µJ, and pulse width of 338 ns at 2066 nm. The maximum average output powers were obtained simultaneously as high as 525 mW at 1944 nm and 323 mW at 2066 nm. The paired-pulse repetition frequency can be pump-tunable in the range of 8-22 kHz. The temporal delay in the paired pulses can be controllable from 9.5 to 2.9 µs with the pump power increasing from 15.2 to 18.4 W. The compact dual-wavelength paired-pulse laser near 2 µm has potential application in the differential absorption lidar.

9.
Small ; 19(12): e2206245, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36587963

ABSTRACT

In recent years, carbon-based CsPbI2 Br perovskite solar cells (PSCs) have attracted more attention due to their low cost and good stability. However, the power conversion efficiency (PCE) of carbon-based CsPbI2 Br PSCs is still no more than 16%, because of the defects in CsPbI2 Br or at the interface with the electron transport layer (ETL), as well as the energy level mismatch, which lead to the loss of energy, thus limiting PCE values. Herein, a series of cadmium halides are introduced, including CdCl2 , CdBr2 and CdI2 for dual direction thermal diffusion treatment. Some Cd2+ ions thermally diffuse downward to passivate the defects inside or on the surface of SnO2 ETL. Meanwhile, the energy level structure of SnO2 ETL is adjusted, which is in favor of the transfer of electron carriers and blocking holes. On the other hand, part of Cd2+ and Cl- ions thermally diffuse upward into the CsPbI2 Br lattice to passivate crystal defects. Through dual direction thermal diffusion treatment by CdCl2 , CdI2 and CdBr2 , the performance of devices has been significantly improved, and their PCE has been increased from 13.01% of the original device to 14.47%, 14.31%, and 13.46%, respectively. According to existing reports, 14.47% is one of the highest PCE of carbon-based CsPbI2 Br PSCs with SnO2 ETLs.

10.
Opt Lett ; 47(22): 5857-5860, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-37219120

ABSTRACT

Microsphere lenses can overcome the optical diffraction limit and can be used to observe features smaller than 200 nm under white light. Inclined illumination benefits from the second refraction of evanescent waves in the microsphere cavity, prohibiting the influence of background noise and improving the imaging resolution and quality of the microsphere superlens. Currently, there is a consensus that microspheres immersed in a liquid environment can improve imaging quality. Microsphere imaging under inclined illumination is performed using barium titanate microspheres immersed in an aqueous environment. However, the background medium of a microlens varies depending on its diverse applications. In this study, the effects of continuously changing background media on the imaging properties of microsphere lens under inclined illumination are investigated. The experimental results demonstrate that the axial position of the microsphere photonic nanojet changes with respect to the background medium. Consequently, owing to the refractive index of the background medium, the imaging magnification and the position of the virtual image change. Using a sucrose solution and polydimethylsiloxane with the same refractive index, we demonstrate that the imaging performance of microspheres is related to the refractive index rather than the background medium type. This study helps associate microsphere superlenses with a more universal application spectrum.

11.
Open Life Sci ; 16(1): 198-209, 2021.
Article in English | MEDLINE | ID: mdl-33817311

ABSTRACT

This study aimed to explore the regulatory mechanisms of miR-338-3p and matrix metalloproteinase-2 (MMP-2) in neuroblastoma. Putative target interaction regions of miR-338-3p on MMP-2 were predicted by miRcode and miRbase bioinformatics tools. Relative expression of miRNA-338-3p and MMP-2 in neuroblastoma tissues and GI-LI-N and SK-N-SH cells was determined by reverse transcription polymerase chain reaction experiment. Furthermore, the cell proliferation was determined by Cell Counting Kit-8 assay, the cell apoptosis rate was analyzed by flow cytometry assay, and the cell invasion was evaluated by transwell assay. miR-338-3p expression was downregulated, whereas MMP-2 expression was upregulated in metastasis tissue site compared to that in primary tissue site in total. Furthermore, miR-338-3p overexpression suppressed proliferation, invasion, and epithelial-mesenchymal transition (EMT) of neuroblastoma cells but promoted apoptosis, and the knockdown of MMP-2 triggered similar effects. Furthermore, MMP-2 was directly targeted by miR-338-3p, and overexpression of MMP-2 rescued the inhibitory effects of miR-338-3p on human neuroblastoma cell progression. Collectively, these data demonstrated that miR-338-3p could suppress cell growth, invasion, and EMT pathway and induce apoptosis in neuroblastoma cells by targeting MMP-2. MiR-338-3p sponged MMP-2 to regulate the PI3K/AKT pathway in human neuroblastoma cells.

12.
Pathogens ; 10(3)2021 Mar 18.
Article in English | MEDLINE | ID: mdl-33803824

ABSTRACT

Duck viral enteritis is a highly contagious and fatal disease of commercial waterfowl flocks. The disease occurs sporadically or epizootically in mainland China due to insufficient vaccinations. Early and rapid diagnosis is important for preventive intervention and the control of epizootic events in clinical settings. In this study, we generated two monoclonal antibodies (MAbs) that specifically recognized the duck enteritis virus (DEV) envelope glycoprotein B and tegument protein UL47, respectively. Using these MAbs, a colloidal gold-based immunochromatographic assay (ICA) was developed for the efficient detection of DEV antigens within 15 min. Our results showed that the detection limit of the developed ICA strip was 2.52 × 103 TCID50/mL for the virus infected cell culture suspension with no cross-reactivity with other pathogenic viruses commonly encountered in commercially raised waterfowl. Using samples from experimentally infected ducks, we demonstrated that the ICA detected the virus in cloacal swab samples on day three post-infection, demonstrating an 80% concordance with the PCR. For tissue homogenates from ducks succumbing to infection, the detection sensitivity was 100%. The efficient and specific detection by this ICA test provides a valuable, convenient, easy to use and rapid diagnostic tool for DVE under both laboratory and field conditions.

13.
Free Radic Biol Med ; 164: 390-398, 2021 02 20.
Article in English | MEDLINE | ID: mdl-33465467

ABSTRACT

The etiology and pathogenesis of Hirschsprung's disease (HSCR) remain largely unknown. We examined colon tissues from three independent populations with a combined analysis of metabolomics, transcriptomics and proteomics to understand HSCR pathogenesis, according to which mouse model was used to examine prostaglandin E2 (PGE2) induced clinical presentation of HSCR. SH-SY5Y and SK-N-BE(2) cell lines were studied for PGE2 inhibited cell migration through EP2. Our integrated multiple 'omics'-analysis suggests that the levels of PGE2, the expression of the gene encoding PGE2 receptor (EP2), and PGE2 synthesis enzyme genes (PTGS1 and PTGES) increased in HSCR colon tissues, together with a decreased synthesis of PGE2-related byproducts. In vivo, the pregnant mice treated with PGE2 gave birth to offspring with the decrease of ganglion cells in their colon and gut function. In in vitro study, when EP2 was blocked, the PGE2-inhibited cell migration was recovered. Our study identified a novel pathway highlighting the link between expression of PTGS1 and PTGES, levels of PGE2, expression of PTGER2, and neural crest cell migration in HSCR, providing a novel strategy for future diagnosis and prevention of HSCR.


Subject(s)
Hirschsprung Disease , Animals , Cell Differentiation , Cell Movement , Dinoprostone , Hirschsprung Disease/genetics , Mice
14.
Exp Ther Med ; 20(2): 1782-1788, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32742409

ABSTRACT

Changes in the levels of interleukin-1ß (IL-1ß), cortisol and chromogranin A (CgA) in saliva of subjects with occupational fatigue were investigated. Doctors in the Emergency Department were selected as research subjects. Saliva was collected before work (after full rest) and after work (≥24 h). Electroencephalogram (EEG) was performed. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of IL-1ß, cortisol and CgA in saliva. In order to obtain permission for human specimens, the study was approved by the Ethics Committee of the Affiliated Hospital of Hebei University of Engineering and registered for clinical trials (registration no. ChiC-TR-DCD-14005746). As there were only 4 subjects in this study without fatigue waves in EEG, and the number of these subjects was not sufficient to constitute a control group, the comparison of the contents of IL-1ß, cortisol and CgA of all subjects before and after working for 18 h was just a confirmation of the statistical results of 43 cases with fatigue waves in the EEG. According to the results, there was no change in the contents of IL-1ß and cortisol in the saliva of subjects with occupational fatigue before and after fatigue, whereas, there was a significant change in the content of CgA before and after fatigue. However, there was no correlation between the content of CgA and fatigue. The results of the present study revealed that IL-1ß, cortisol and CgA indicators are not suitable diagnostic markers for occupational fatigue.

16.
Prostate ; 80(10): 764-776, 2020 07.
Article in English | MEDLINE | ID: mdl-32356608

ABSTRACT

BACKGROUND: Aging is the most important risk factor for prostate cancer (PCa), but how age contributes to PCa is poorly understood. Aging is characterized by low-grade systemic inflammation (i.e., inflammaging) that is often attributed to the progressive activation of immune cells over time, which may play an important role in prostate carcinogenesis. Th17 response is elevated in aging humans and mice, but it remains unknown whether it is increased in prostate tissue or contributes to prostate carcinogenesis during aging. In this study, we aimed to determine the role of age-related Th17 response in PCa cell growth, migration, and invasion. METHODS: C57BL/6J (B6) mouse was used as an aging animal model and the prostate histopathology during aging was analyzed. Splenic CD4+ T cells were isolated from young (16-20 weeks old) and aged (96-104 weeks old) mice, and cultured in the presence of plate-bound anti-CD3/anti-CD28, with or without Th17 differentiation conditions. The cells were collected and used for subsequent flow cytometry or quantitative reverse transcription polymerase chain reaction. The supernatant was collected and used to treat PCa cell lines. The treated PCa cells were analyzed for cell viability, migration, invasion, and nuclear factor kappa B (NF-κB) signaling. RESULTS: Aged mice had enlarged prostate glands and increased morphological alterations, with not only increased inflammatory cell infiltration but also increased Th17 cytokines in prostate tissue, compared to young mice. Naïve CD4+ T cells from aged mice differentiated increased interleukin (IL)-17-expressing cells. CD4+ T cells from aged mice spleen had increased Th17 cells, Th17 cytokines and Th17/Treg ratio compared to young mice. Factors secreted from aged CD4+ T cells, especially from ex vivo differentiated Th17 cells, not only promoted PCa cell viability, migration, and invasion but also activated the NF-κB signaling in PCa cells compared to young mice. CONCLUSIONS: These results indicate that age-related CD4+ T cells, especially Th17 cells-secreted factors have the potential to contribute to prostate carcinogenesis. Our work could prompt further research using autochthonous PCa mouse models at different ages to elucidate the functional role of Th17 response in prostate carcinogenesis during aging.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Prostatic Neoplasms/immunology , Th17 Cells/immunology , Aging/immunology , Animals , CD4-Positive T-Lymphocytes/pathology , Cell Differentiation/immunology , Cell Line, Tumor , Cell Movement/immunology , Humans , Inflammation/immunology , Inflammation/pathology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Models, Animal , NF-kappa B/immunology , Neoplasm Invasiveness , PC-3 Cells , Prostatic Neoplasms/pathology , Th17 Cells/pathology
17.
Pathogens ; 9(2)2020 Feb 04.
Article in English | MEDLINE | ID: mdl-32033063

ABSTRACT

Salmonella infection not only causes acute and chronic diseases in poultry flocks, but the infected poultry are among the most important reservoirs for a variety of Salmonella serovars frequently transmitted to humans. This study aimed to investigate the occurrence of Salmonella spp. in local poultry farms in China. Samples (n = 4255), including dead-in-shell embryos, culled day-old-hatchings and 1- to 4-week-old diseased birds, were collected for Salmonella culture from broiler chicken, meat-type duck and pigeon farms in northern China between 2014 and 2018. A total of 103 Salmonella were isolated. S. enterica serovar Enteritidis and S. Typhimurium were the most prevalent serovars, representing 53.4% and 34.9% of the isolates, respectively. Serovar diversity was the highest in ducks, with the S. Apeyeme being isolated for the first time from duck tissues. All isolates were characterized by multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). MLST showed that all S. Enteritidis isolates shared the same sequence type (ST11), and Typhimurium showed several rare STs in addition to ST19. In comparison, PFGE showed better discrimination for S. Enteritidis and S. Typhimurium isolates, with nine distinct pulsotypes being observed. The isolates exhibited varying degrees of resistance to 15 tested antimicrobials and identified S. Enteritidis isolates (98.18%) with multiple antimicrobial resistance were a cause for concern. Our data on invasive Salmonella infection in meat-type poultry in local farms can be used to identify sources and factors associated with Salmonella spread in poultry and the associated food chain.

18.
J Virol ; 94(8)2020 03 31.
Article in English | MEDLINE | ID: mdl-32024774

ABSTRACT

Tembusu virus (TMUV) is a flavivirus responsible for panzootic outbreaks of severe egg-drop and fatal encephalitis of domestic waterfowl in China. Although TMUV can be attenuated by in vitro passaging, experimental evidence supporting the role of specific genetic changes in virulence attenuation is currently lacking. Here, we performed site-directed mutagenesis on five envelope (E) protein amino acid residues in accordance with the attenuated TMUV generated in our recent study. Our results showed that the Thr-to-Lys mutation of residue 367 in E protein (E367) plays a predominant role in viral cell adaptation and virulence attenuation in ducks compared with mutations in other residues. We further demonstrated that the positively charged basic amino acid substitution at E367 enhanced the viral binding affinity for glycosaminoglycans (GAGs) and reduced viremia levels and the efficiency of replication in major target organs in subcutaneously inoculated ducks. Interestingly, the T367K mutation increased viral neutralization sensitivity to the early immune sera. Together, our findings provide the first evidence that a basic amino acid substitution at E367 strongly impacts the in vitro and in vivo infection of TMUV.IMPORTANCE Outbreaks of Tembusu virus (TMUV) infection have caused huge economic losses in the production of domestic waterfowl since the virus was first recognized in China in 2010. To control TMUV infection, a live-attenuated vaccine candidate of TMUV was developed in our previous study, but the mechanisms of virulence attenuation are not fully understood. Here, we found that the Thr-to-Lys substitution at E367 is a crucial determinant of TMUV virulence attenuation in ducks. We demonstrated that the T367K mutation attenuates TMUV through reducing viral replication in the blood, brain, heart (ducklings), and ovaries. These data provide new insights into understanding the pathogenesis of TMUV and the rational development of novel TMUV vaccines.


Subject(s)
Amino Acid Substitution , Flavivirus Infections/immunology , Flavivirus Infections/virology , Flavivirus/genetics , Viral Envelope Proteins/genetics , Amino Acid Substitution/immunology , Animals , Antibodies, Neutralizing , Cell Line , China/epidemiology , Ducks/virology , Female , Flavivirus Infections/epidemiology , Flavivirus Infections/pathology , Mutagenesis, Site-Directed , Mutation , Poultry Diseases/immunology , Poultry Diseases/mortality , Poultry Diseases/pathology , Poultry Diseases/virology , Viral Load , Virulence , Virus Replication
19.
J Hazard Mater ; 388: 122016, 2020 Apr 15.
Article in English | MEDLINE | ID: mdl-31958614

ABSTRACT

In this study, tannery wastewater was used as carbon source to hydrothermally synthesize magnetic carbon-coated nickel ferrite composite (NiFe2O4@C), which was employed as a catalyst for thallium (Tl) oxidation by hypochlorite and simultaneously as an adsorbent for Tl removal from wastewater. Compared with NiFe2O4@C adsorption or hypochlorite oxidation alone, the combination of NiFe2O4@C and hypochlorite substantially enhanced the rate and efficiency of Tl(I) removal. In addition, this process was highly effective for Tl(I) removal over a wide pH range (6-12). The maximum Tl(I) removal capacity was 1699 mg/g at pH 10, which is the highest one reported so far. Electron spin resonance spectra suggested the formation of hypochlorite-based free radicals induced by the NiFe2O4@C composite, which enhanced the Tl(I) oxidation and removal. Oxidation-induced surface precipitation and surface complexation were found to be the main Tl(I) removal mechanisms. Consecutive cyclic regeneration tests implied robust regeneration and reuse performance of the composite. Moreover, it was effective for Tl(I) removal from real industrial wastewater. Therefore, the hypochlorite catalytic oxidation coupled with adsorption by the magnetic NiFe2O4@C composite is a promising technique for Tl(I) removal from wastewater. This hybrid process also has great potential for the removal of other pollutants.

20.
J Hazard Mater ; 386: 121900, 2020 03 15.
Article in English | MEDLINE | ID: mdl-31896005

ABSTRACT

Nano zero-valent metals adsorption coupled with advanced oxidation for environmental pollutants removal has been gaining attention recently. In this study, zero-valent iron-manganese (nZVIM) bimetallic nanocomposites were prepared via one-pot borohydride reduction and coupled with hypochlorite (ClO-) oxidation for enhanced thallium (Tl) removal from wastewater. Amorphous nZVIM nanoparticles were successfully synthesized, with a specific surface area of 106.89 m2/g, and a saturation magnetization of 65.16 emu/g. In comparison with the nZVIM adsorption or ClO- oxidation alone, the hybrid nZVIM/ClO- process achieved much faster Tl(I) removal rate over a wide pH range from 6 to 10. Maximum Tl(I) removal capacity was as high as 990.0 mg/g. The oxidation-induced adsorption for Tl(I) removal well followed the pseudo-first kinetic order model. Stable and effective adsorbent regeneration was achieved during the cyclic adsorption-desorption tests. This process also had high resistance to the interference of external cations, can act as an effective pretreatment for Tl(I) removal from the actual saline industrial wastewater. The main mechanisms for Tl(I) removal were found to be oxidation, surface precipitation, pore retention, and surface complexation. The nZVIM coupled with ClO- approach has great potential for Tl(I) removal from wastewater, and its application in other fields is highly anticipated.

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