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1.
Chem Commun (Camb) ; 60(18): 2512-2515, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38334048

RESUMEN

High entropy polyanionic Na3V1.9(Ca,Mg,Cr,Ti,Mn)0.1(PO4)3 was synthesized, which activated a reversible redox reaction of V4+/V5+ and reached a remarkable capacity of 116 mA h g-1 at 1C and maintained 90% capacity retention after 1000 cycles at 10C. Structure evolution and sodium storage mechanisms were revealed by an in situ XRD method, which disclosed the high-entropy effect of material design. Together with the full battery tests, these findings promote the wide applications of high-entropy polyanionic cathodes in SIBs.

2.
BMJ Glob Health ; 8(12)2023 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-38135296

RESUMEN

INTRODUCTION: We analysed case-contact clusters during the Omicron BA.2 epidemic in Shanghai to assess the risk of infection of contacts in different settings and to evaluate the effect of demographic factors on the association of infectivity and susceptibility to the Omicron variant. METHODS: Data on the settings and frequency of contact, demographic characteristics and comorbidities of index cases, contacts and secondary cases were analysed. Independent effect of multiple variables on the risk for transmission and infection was evaluated using generalised estimating equations. RESULTS: From 1 March to 1 June 2022, we identified 450 770 close contacts of 90 885 index cases. The risk for infection was greater for contacts in farmers' markets (fixed locations where farmers gather to sell products, adjusted OR (aOR): 3.62; 95% CI 2.87 to 4.55) and households (aOR: 2.68; 95% CI 2.15 to 3.35). Children (0-4 years) and elderly adults (60 years and above) had higher risk for infection and transmission. During the course of the epidemic, the risk for infection and transmission in different age groups initially increased, and then decreased on about 21 April (17th day of citywide home quarantine). Compared with medical workers (reference, aOR: 1.00), unemployed contacts (aOR: 1.77; 95% CI 1.53 to 2.04) and preschoolers (aOR: 1.61; 95% CI 1.26 to 2.05) had the highest risk for infection; delivery workers (aOR: 1.90, 95% CI 1.51 to 2.40) and public service workers (aOR: 1.85; 95% CI 1.64 to 2.10) had the highest risk for transmission. Contacts who had comorbidities (aOR: 1.10; 95% CI 1.09 to 1.12) had a higher risk for infection, particularly those with lung diseases or immune deficiency. CONCLUSION: Farmers' markets and households were the main setting for transmission of Omicron. Children, the elderly, delivery workers and public service workers had the highest risk for transmission and infection. These findings should be considered when implementing targeted interventions.


Asunto(s)
COVID-19 , Epidemias , Adulto , Niño , Anciano , Humanos , SARS-CoV-2 , China/epidemiología
3.
Anal Chim Acta ; 1278: 341748, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37709476

RESUMEN

The development of a sensitive method for early cancer diagnosis is very important because the early diagnosis of cancer is crucial in preventing the spread of cancer cells and improving patient survival rates. Recent studies showed that cancer cell membranes have lower polarity than normal cell membranes, which provides a new approach for cancer diagnosis at the cell membrane level. We developed herein a highly sensitive cell membrane polarity probe (Cal-M) for early diagnosis of cancer. This probe has low cytotoxicity, good photostability, near-infrared (NIR) fluorescence emission (>700 nm), large Stokes shift, high sensitivity for polarity, excellent cell membrane localization performance, and the ability to selectively light up cancer cells. Using this probe staining, the fluorescence of cancer cells is ∼63 times higher than that of normal cells, demonstrating excellent sensitivity and selectivity of Cal-M. This probe was also successfully used to detect polarity changes on cancer cell membranes and selectively visualize tumors in mice. Notably, the tumor could be visualized sensitively with a size as small as 1.37 mm3, indicating that Cal-M is promising for early diagnosis of tumors.


Asunto(s)
Neoplasias , Animales , Ratones , Membrana Celular , Neoplasias/diagnóstico por imagen , Colorantes Fluorescentes , Coloración y Etiquetado
4.
Arch Oral Biol ; 155: 105801, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37696160

RESUMEN

OBJECTIVE: The aim of this study was to explore the correlation between oral microbiota and NLRP3 inflammasome in type 2 diabetes, and to preliminarily explore their possible impact on type 2 diabetes. DESIGN: The 16S rDNA sequencing technique was used to analyze the microbial composition in the saliva of patients with T2DM and healthy people. Real-time quantitative PCR (RT-qPCR) was used to detect the expression levels of T2DM-related inflammatory cytokines in the blood of two groups. RESULTS: The relative abundances of Fusobacteriota and Campilobacterota in the saliva of patients with T2DM were lower than those of healthy people (P < 0.05), whereas the relative abundance of Proteobacteria in patients with T2DM was higher than that of healthy people (P < 0.05). In addition, real-time quantitative PCR results showed changes in inflammasome-associated factors in the blood of patients with T2DM and healthy people. Compared with healthy individuals, the relative expression levels of lipopolysaccharide (LPS), apoptosis-associated point-like protein (ASC), Caspase-1, Caspase-11, nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3), and interleukin (IL)-1ß were significantly higher in the blood of patients with T2DM, whereas the expression level of insulin receptor substrate-1 (IRS-1) was reduced (P < 0.05). CONCLUSIONS: Our research suggested that changes in the ratio of oral microbial taxa might increase the expression levels of inflammatory and T2DM-related factors by activating the NLRP3 inflammasome pathway. This discovery indicated the imbalance in oral microbiota might have a certain influence on diabetes by triggering an inflammatory response, and provided a new idea for the relationship between T2DM and oral microbiota.


Asunto(s)
Diabetes Mellitus Tipo 2 , Microbiota , Humanos , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Diabetes Mellitus Tipo 2/genética , Caspasa 1/metabolismo , Caspasas , Interleucina-1beta/metabolismo
5.
Anal Chem ; 95(18): 7254-7261, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37125920

RESUMEN

Cancer is a worldwide health problem. Revealing the changes in the microenvironment after cell carcinogenesis is helpful to understand cancer and develop sensitive methods for cancer diagnosis. We developed herein a viscosity-responsive plasma membrane probe (TPA-S) that was successfully used to probe the viscosity difference between normal and tumor cell plasma membranes for the first time. The probe shows AIE properties with good water solubility, significant near-infrared (NIR) fluorescence responses to viscosity with high sensitivity, and excellent cell membrane location performance. With these features, our experiments showed that TPA-S could selectively visualize cancer cell plasma membranes, revealing that the plasma membrane of tumor cells is more viscous than that of normal cells. In addition, TPA-S was successfully applied to specifically light up tumors. Altogether, this work explored the changes of cell membrane viscosity after canceration, provided a new method for selective visualization of tumor cells, and opened up a new approach for cancer diagnosis.


Asunto(s)
Neoplasias , Humanos , Viscosidad , Membrana Celular/metabolismo , Neoplasias/diagnóstico por imagen , Neoplasias/metabolismo , Fluorescencia , Carcinogénesis , Colorantes Fluorescentes/metabolismo , Células HeLa , Microambiente Tumoral
6.
BMC Public Health ; 23(1): 743, 2023 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-37087436

RESUMEN

BACKGROUND: From March to June 2022, an Omicron BA.2 epidemic occurred in Shanghai. We aimed to better understand the transmission dynamics and identify age-specific transmission characteristics for the epidemic. METHODS: Data on COVID-19 cases were collected from the Shanghai Municipal Health Commission during the period from 20th February to 1st June. The effective reproductive number (Rt) and transmission distance between cases were calculated. An age-structured SEIR model with social contact patterns was developed to reconstruct the transmission dynamics and evaluate age-specific transmission characteristics. Least square method was used to calibrate the model. Basic reproduction number (R0) was estimated with next generation matrix. RESULTS: R0 of Omicron variant was 7.9 (95% CI: 7.4 to 8.4). With strict interventions, Rt had dropped quickly from 3.6 (95% CI: 2.7 to 4.7) on 4th March to below 1 on 18th April. The mean transmission distance of the Omicron epidemic in Shanghai was 13.4 km (95% CI: 11.1 to 15.8 km), which was threefold longer compared with that of epidemic caused by the wild-type virus in Wuhan, China. The model estimated that there would have been a total 870,845 (95% CI: 815,400 to 926,289) cases for the epidemic from 20th February to 15th June, and 27.7% (95% CI: 24.4% to 30.9%) cases would have been unascertained. People aged 50-59 years had the highest transmission risk 0.216 (95% CI: 0.210 to 0.222), and the highest secondary attack rate (47.62%, 95% CI: 38.71% to 56.53%). CONCLUSIONS: The Omicron variant spread more quickly and widely than other variants and resulted in about one third cases unascertained for the recent outbreak in Shanghai. Prioritizing isolation and screening of people aged 40-59 might suppress the epidemic more effectively. Routine surveillance among people aged 40-59 years could also provide insight into the stage of the epidemic and the timely detection of new variants. TRIAL REGISTRATION: We did not involve clinical trial.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , SARS-CoV-2 , China/epidemiología , Factores de Edad
7.
Artículo en Inglés | MEDLINE | ID: mdl-36767495

RESUMEN

An urban emergency shelter provides a place of temporary life and shelter for victims after a disaster. As a very important public service facility, its spatial layout is greatly related to the security of lives and the property of the urban residents. Upholding the concept of sustainable disaster reduction, this study took the central urban area of Xuzhou as an example. Based on the analysis of ArcGIS software, this study analyzed and planned the spatial layout of emergency shelters in Xuzhou and visualized the service area ratio, service population ratio, service capacity ratio, and service overlap rate of each administrative district. Finally, 73 fixed emergency shelters were determined, among which eight were classified as central shelters. At the same time, through consulting the relevant data, it was found that similar problems such as potential safety hazard, blind areas, service overlapping, and mismatch of shelter layout and actual needs also exist in other cities. Finally, in light of the existing problems, relevant suggestions are provided for the adjustment and optimization of the layout of emergency shelters.


Asunto(s)
Planificación en Desastres , Desastres , Refugio de Emergencia , Ciudades
8.
BMC Infect Dis ; 23(1): 10, 2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36609217

RESUMEN

BACKGROUND: During October 2021, China experienced localized outbreaks of COVID-19 in many cities. We analyzed the small local outbreak in Zunyi (Guizhou Province), a major city in southwestern China, and modeled the effects of different interventions on this outbreak. METHODS: Data on infections and contacts, provided by the Health Commission of Guizhou Province, were used to analyze the epidemiological characteristics of the outbreak and calculate the effectiveness of vaccination. A branching process model was used to simulate the outbreak. This model considered the time interval from exposure of the initial case to confirmation, the number of potential infections caused by the initial case, and the effects of the different interventions. RESULTS: From 18 to 25 October 2021, there were 12 patients with COVID-19 in Zunyi. Overall, the average age was 67.17 years-old, 8 patients were females, and 1 patient had an asymptomatic infection. The effectiveness of two-dose inactivated vaccine against SARS-CoV-2 infection was 16.7% (95% CI: 2.8% to 99.7%). The initial case was infected on 11 or 12 October 2021, 6.40 (95% CI: 6.37, 6.42; IQR: 4.92, 7.63) days before confirmation while the travelling in Lanzhou (Gansu Province). There were 10.07 (95% CI: 10.04, 10.09; IQR: 7.86, 11.93) potential secondary cases. When the effective vaccine coverage reached 60%, the probability of cumulative cases exceeding 20 was less than 8.77%, even if contact tracing was relaxed or eliminated. However, if the probability of tracing contacts decreased, earlier initiation of nucleic acid testing was necessary to control the outbreak. CONCLUSIONS: The COVID-19 outbreak in Zunyi was controlled quickly due to moderately effective vaccine coverage and rapid contact tracing. For controlling localized outbreaks, vaccination and contact tracing seemed to be more effective than massive nucleic acid testing in the initial phase of transmission. However, if there is low effective vaccine coverage or insufficient contact tracing, nucleic acid testing should start earlier.


Asunto(s)
COVID-19 , Ácidos Nucleicos , Vacunas , Femenino , Humanos , Anciano , Masculino , COVID-19/epidemiología , COVID-19/prevención & control , Trazado de Contacto , SARS-CoV-2 , Vacunas contra la COVID-19 , Brotes de Enfermedades/prevención & control , China/epidemiología
9.
BMC Infect Dis ; 22(1): 845, 2022 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-36371145

RESUMEN

BACKGROUND: From 20 July to 26 August 2021, local outbreaks of COVID-19 occurred in Nanjing City and Yangzhou City (Jiangsu Province, China). We analyzed the characteristics of these outbreaks in an effort to develop specific and effective intervention strategies. METHODS: Publicly available data on the characteristics of the COVID-19 outbreaks in Jiangsu Province were collected. Logistic regression was used to assess the association of age and sex with clinical severity. Analysis of onset dates, generation time distributions, and locations were used to estimate the mean transmission distance. A branching process model was used to evaluate different management strategies. RESULTS: From 20 July to 26 August 2021, 820 patients were diagnosed with COVID-19 in Jiangsu Province, with 235 patients (28.7%) from Nanjing, 570 (69.5%) from Yangzhou, and 15 (1.8%) from other cities. Overall, 57.9% of the patients were female, 13.7% were under 20 years-old, and 58.3% had moderate disease status. The mean transmission distance was 4.12 km, and closed-loop management of the area within 2.23 km of cases seemed sufficient to control an outbreak. The model predicted that the cumulative cases in Yangzhou would increase from 311 to 642 if the interval between rounds of nucleic acid amplification testing (NAAT) increased from 1 to 6 days. It also predicted there would be 44.7% more patients if the NAAT started 10 days (rather than 0 days) after diagnosis of the first case. The proportion of cases detected by NAAT would increase from 11.16 to 44.12% when the rounds of NAAT increased from 1 to 7 within 17 days. When the effective vaccine coverage was 50%, the outbreak would be controlled even when using the most relaxed non-pharmaceutical interventions. CONCLUSIONS: The model predicted that a timely closed-loop management of a 2.23 km area around positive COVID-19 cases was sufficient to control the outbreak. Prompt serial NAAT is likely to contain an outbreak quickly, and our model results indicated that three rounds of NAAT sufficiently controlled local transmission. Trial registration We did not involve clinical trial.


Asunto(s)
COVID-19 , Ácidos Nucleicos , Humanos , Femenino , Adulto Joven , Adulto , Masculino , COVID-19/epidemiología , SARS-CoV-2 , Brotes de Enfermedades/prevención & control , China/epidemiología
10.
Infect Dis Poverty ; 11(1): 106, 2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36221140

RESUMEN

BACKGROUND: Elimination of hepatitis B virus (HBV) is a striking challenge for countries with high or moderate disease burden. Therefore, using China as a practical case to share experiences for similar countries may accelerate the achievement of the WHO 2030 target of 90% reduction in HBV-related incidence. We aim to evaluate the impact of national HBV immunization strategies in China; and the feasibility to achieve WHO 2030 targets under different scenarios. METHODS: We constructed an expanded Susceptible-Exposed-Infectious-Recovered (SEIR) model and decision tree-Markov model to estimate the epidemic of HBV in China, assess the feasibility of 2030 Elimination Goals through the projections and conduct the economic analysis. Least square method was used to calibrate the expanded SEIR model by yearly data of laboratory-confirmed HBV cases from 1990 to 2018. Two models were separately used to evaluate the impact and cost-effectiveness of HBV vaccine by comparing prevalence of chronic HBV infections, quality-adjusted life-years (QALYs), incremental cost effectiveness ratio and benefit-cost ratio (BCR) under various intervention options, providing a basis for exploring new containment strategies. RESULTS: Between 1990 and 2020, the number of chronic HBV infections decreased by 33.9%. The current status quo would lead to 55.73 million infections (3.95% prevalence) in 2030, compared to 90.63 million (6.42% prevalence) of the "Without the NIP" scenario (NIP: National Immunization Program), 114.78 million (8.13% prevalence) without any interventions. The prevention of mother to child transmission (PMTCT) strategy showed a net benefit as 12,283.50 dollars per person, with BCR as 12.66, which is higher than that of universal vaccination at 9.49. Compared with no screening and no vaccination, the PMTCT strategy could save 7726.03 dollars for each QALY increase. CONCLUSIONS: Our findings proved the HBV vaccination has demonstrated a substantial positive impact on controlling the epidemic of HBV in terms of effectiveness and economy after about 30 years of implementation of the national hepatitis B immunization program which also provided containment experience for high or medium burden countries. As for China, the next step should focus on exploring strategies to improve diagnosis and treatment coverage to reduce the burden of HBV-related deaths and ultimately eliminate HBV.


Asunto(s)
Vacunas contra Hepatitis B , Hepatitis B , Programas de Inmunización , China/epidemiología , Análisis Costo-Beneficio , Femenino , Hepatitis B/epidemiología , Hepatitis B/prevención & control , Hepatitis B/transmisión , Vacunas contra Hepatitis B/administración & dosificación , Hepatitis B Crónica/epidemiología , Hepatitis B Crónica/prevención & control , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Embarazo , Evaluación de Programas y Proyectos de Salud
11.
Int J Biol Macromol ; 220: 371-384, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-35970372

RESUMEN

Atherosclerosis (AS) is the pathological basis of many cardiovascular and cerebrovascular diseases, in which macrophage-derived foam cells are the critical step and a typical pathological feature of early atherosclerosis. We previously confirmed that low-molecular-weight fucoidan (LMWF) had a good anti-AS effect, but the mechanism is still unclear. Here with aim to investigate the inhibitory effect of LMWF on foam cells and its molecular mechanism. Oil red O staining showed that LMWF effectively alleviated lipid accumulation and the formation of foam cells. Flow cytometry detection showed that LMWF promoted foam cells apoptosis. In addition, immunofluorescence showed that LMWF inhibited macrophage scavenger receptor A1 (SR-A1)-mediated lipid uptake and promoted ATP-binding cassette transporter A1 (ABCA1)-mediated cholesterol outflow. Western blot showed that LMWF downregulated SR-A1 protein expression and upregulated ABCA1 protein expression by inhibiting p38 mitogen activated protein kinase (p38MAPK) phosphorylation. Moreover, the mRNA transcriptions of Stat1, Elk-1, and Myc were downregulated when treated with LMWF. It concluded that, LMWF achieved bidirectional regulation of SR-A1 and ABCA1, then prevented the formation of foam cells, finally ameliorated the development of AS.


Asunto(s)
Aterosclerosis , Proteínas Quinasas p38 Activadas por Mitógenos , Transportador 1 de Casete de Unión a ATP/genética , Transportador 1 de Casete de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 1/genética , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 1/metabolismo , Aterosclerosis/genética , Antígenos CD36/genética , Antígenos CD36/metabolismo , Colesterol/metabolismo , Humanos , Lipoproteínas LDL/metabolismo , Fosforilación , Polisacáridos , ARN Mensajero/metabolismo , Receptores Depuradores/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
12.
Front Bioeng Biotechnol ; 10: 960586, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35935505

RESUMEN

Hagfish slime proteins have long been considered useful due to their potential applications in novel green, environmental, and functional bionic materials. The two main component proteins in the slime thread of hagfish, (opt)EsTKα and (opt)EsTKγ, were used as raw materials. However, the methods available to assemble these two proteins are time- and labor-intensive. The conditions affecting protein self-assembly, such as the pH of the assembly buffer, protein concentration, and the protein addition ratio, were the subject of the present research. Through a series of tests, the self-assembly results of a variety of assembly conditions were explored. Finally, a simplified protein self-assembly method was identified that allows for simple, direct assembly of the two proteins directly. This method does not require protein purification. Under the optimal assembly conditions obtained by exploration, a new gel material was synthesized from the hagfish protein through self-assembly of the (opt)EsTKα and (opt)EsTKγ. This assembly method has the benefits of being a simple, time-saving, and efficient. The self-assembled protein gel products were verified by SDS polyacrylamide gel electrophoresis (SDS-PAGE) and contained (opt)EsTKα and (opt)EsTKγ proteins. Scanning electron microscopy (SEM) was used to investigate the self-assembled protein gel after freeze-drying, and it was observed that the self-assembled protein formed a dense, three-dimensional porous network structure, meaning that it had good water retention. Evaluation of the gel with atomic force microscopy (AFM) indicated that the surface of the protein fiber skeleton show the network-like structure and relatively smooth. Characterization by circular dichroism (CD) and Fourier transform infrared spectroscopy (FT-IR) demonstrated that the two proteins were successfully assembled, and that the assembled protein had a secondary structure dominated by α-helices. The rheological properties of the self-assembled products were tested to confirm that they were indeed hydrogel property.

13.
Hum Vaccin Immunother ; 18(6): 2099166, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-35905384

RESUMEN

Vaccination for the novel coronavirus disease 2019 (COVID-19) provides an effective approach for the general improvement of social safety and individual health. To date, few studies have analyzed the adoption of COVID-19 vaccines from an entire impact process perspective. Using the health belief model (HBM) and the valence theory, this research evaluates the impact process of vaccine adoption for COVID-19. The respondents in this study were individuals who have been vaccinated in China. The effective sample included 595 individuals. Four valuable and novel findings are identified through this research. First, neither perceived susceptibility nor perceived severity has a statistically significant impact on the benefits from vaccination, threats from vaccination and self-efficacy. Second, benefits from vaccination produce a significant positive effect on self-efficacy and vaccine adoption. Third, threats from vaccination produce a significant negative effect on self-efficacy and vaccine adoption. Fourth, both self-efficacy and cues to adoption produce a significantly positive impact on vaccine adoption. Our theoretical model, which is the main contribution of this research, indicates that individual vaccine adoption is simply a process that leads from behavioral cognition to behavioral intention, rather than from psychological perception to behavioral cognition and then from behavioral cognition to behavioral intention.


Asunto(s)
COVID-19 , Vacunas , Humanos , Vacunas contra la COVID-19 , COVID-19/prevención & control , Vacunación , Intención
14.
Appl Microbiol Biotechnol ; 106(13-16): 5167-5178, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35851417

RESUMEN

Glaesserella parasuis is an important bacterial pathogen that affects the swine industry worldwide. Research on the pathogenic mechanism and genetically engineered vaccine remains undeveloped because an effective markerless and multiple-gene knockout system is unavailable for G. parasuis yet. To establish a markerless knockout, deleted allelic genes with kanamycin resistance (KanR) cassettes were introduced into the genome of G. parasuis by using natural transformation with suicide plasmids. Then, the KanR cassette was excised with a thermosensitive plasmid pGF conferring a constitutive Flp expression. To realize the markerless and multiple-gene knockout, plasmid pGAF was constructed by placing the Flp gene under the control of an arabinose-inducible promoter. Firstly, pGAF was introduced into G. parasuis by electroporation, and the marked mutants were produced following natural transformation. Finally, the KanR cassette was excised from the genome by the inducible expression of Flp upon arabinose action. Based on the natural transformation and the inducible expression of Flp, the markerless single-gene knockout mutants of ΔhsdR, ΔneuA2, ΔespP2, Δapd, and ΔnanH were constructed. In addition, a five-gene knockout mutant of ΔhsdRΔneuA2ΔespP2ΔapdΔnanH was generated by successive natural transformation with five suicide plasmids. Taken together, a markerless and multiple-gene deletion system was established for G. parasuis in the present study for the first time. This system is simple, efficient, and easy to manipulate for G. parasuis; thus, our technique will substantially aid the understanding of the etiology, pathogenesis, and genetic engineering of G. parasuis and other bacteria that can be naturally transformed in laboratory conditions. KEY POINTS: • Flp recombinase excised the KanR gene flanked by FRT sites in Glaesserella parasuis. • The regulatory expression of Flp enabled a multiple-gene knockout forG. parasuis. • The technique will promote the understanding of Glässer's disease pathogens.


Asunto(s)
Arabinosa , Haemophilus parasuis , Animales , ADN Nucleotidiltransferasas/genética , Técnicas de Inactivación de Genes , Haemophilus parasuis/genética , Haemophilus parasuis/metabolismo , Humanos , Porcinos
15.
Infect Dis Poverty ; 11(1): 69, 2022 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-35717198

RESUMEN

BACKGROUND: The pandemic of coronavirus disease 2019 (COVID-19) has changed human behavior in areas such as contact patterns and mask-wearing frequency. Exploring human-human contact patterns and mask-wearing habits in high-risk groups is an essential step in fully understanding the transmission of respiratory infection-based diseases. This study had aims to quantify local human-human (H-H) contacts in high-risk groups in representative provinces of China and to explore the occupation-specific assortativity and heterogeneity of social contacts. METHODS: Delivery workers, medical workers, preschoolers, and students from Qinghai, Shanghai, and Zhejiang were recruited to complete an online questionnaire that queried general information, logged contacts, and assessed the willingness to wear a mask in different settings. The "group contact" was defined as contact with a group at least 20 individuals. The numbers of contacts across different characteristics were assessed and age-specific contact matrices were established. A generalized additive mixed model was used to analyze the associations between the number of individual contacts and several characteristics. The factors influencing the frequency of mask wearing were evaluated with a logistic regression model. RESULTS: A total of 611,287 contacts were reported by 15,635 participants. The frequency of daily individual contacts averaged 3.14 (95% confidence interval: 3.13-3.15) people per day, while that of group contacts was 37.90 (95% CI: 37.20-38.70). Skin-to-skin contact and long-duration contact were more likely to occur at home or among family members. Contact matrices of students were the most assortative (all contacts q-index = 0.899, 95% CI: 0.894-0.904). Participants with larger household sizes reported having more contacts. Higher household income per capita was significantly associated with a greater number of contacts among preschoolers (P50,000-99,999 = 0.033) and students (P10,000-29,999 = 0.017). In each of the public places, the frequency of mask wearing was highest for delivery workers. For preschoolers and students with more contacts, the proportion of those who reported always wearing masks was lower (P < 0.05) in schools/workplaces and public transportation than preschoolers and students with fewer contacts. CONCLUSIONS: Contact screening efforts should be concentrated in the home, school, and workplace after an outbreak of an epidemic, as more than 75% of all contacts, on average, will be found in such places. Efforts should be made to improve the mask-wearing rate and age-specific health promotion measures aimed at reducing transmission for the younger demographic. Age-stratified and occupation-specific social contact research in high-risk groups could help inform policy-making decisions during the post-relaxation period of the COVID-19 pandemic.


Asunto(s)
COVID-19 , Pandemias , COVID-19/epidemiología , COVID-19/prevención & control , China/epidemiología , Brotes de Enfermedades , Humanos , Pandemias/prevención & control , SARS-CoV-2
16.
BMC Infect Dis ; 22(1): 488, 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35606696

RESUMEN

BACKGROUND: Tuberculosis (TB) has a serious impact on people's health. China is one of 30 countries that has a high TB burden. As the currently decreasing speed of the incidence of TB, the WHO's goal of "End TB Strategy" is hard to achieve by 2035. As a result, a SEIR model that determines the impact of different tuberculosis preventive treatments (TPTs) in different age groups, and the effect of different interventions on latent TB infections (LTBIs) in China is developed. METHODS: A Susceptible-Exposed-Infectious-Recovered (SEIR) model was established. Goodness-of-fit tests were used to assess model performance. Predictive analysis was used to assess the effect of different interventions on LTBIs and achieving the goals of the "End TB Strategy". RESULTS: The Chi-square test indicated the model provided a good statistical fit to previous data on the incidence of TB (χ2 = 0.3085, p > 0.999). The 1HP treatment regimen (daily rifapentine + isoniazid for 4 weeks) was most effective in reducing the number of TB cases by 2035. The model indicated that several strategies could achieve the 2035 target of the "End TB Strategy": completion of active case finding (ACF) for LTBI and TPT nation-wide within 5 years; completion of ACF for LTBIs and TPT within 2 years in high-incidence areas; completion of TPT in the elderly within 2 years; or introduction of a new vaccine in which the product of annual doses and vaccine efficiency in the three age groups above 14 years old reached 10.5 million. CONCLUSION: The incidence of TB in China declined gradually from 2005 to 2019. Implementation of ACF for LTBIs and TPT nation-wide or in areas with high incidence, in the elderly, or administration of a new and effective vaccine could greatly reduce the number of TB cases and achieve the 2035 target of the "End TB Strategy" in China.


Asunto(s)
Tuberculosis Latente , Tuberculosis , Adolescente , Anciano , Antituberculosos/uso terapéutico , China/epidemiología , Humanos , Incidencia , Isoniazida/uso terapéutico , Tuberculosis Latente/tratamiento farmacológico , Tuberculosis Latente/epidemiología , Tuberculosis Latente/prevención & control , Tuberculosis/tratamiento farmacológico , Tuberculosis/epidemiología , Tuberculosis/prevención & control
17.
Infect Dis Poverty ; 11(1): 36, 2022 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-35346382

RESUMEN

BACKGROUND: While a COVID-19 vaccine protects people from serious illness and death, it remains a concern when and how to lift the high-cost and strict non-pharmaceutical interventions (NPIs). This study examined the joint effect of vaccine coverage and NPIs on the control of local and sporadic resurgence of COVID-19 cases. METHODS: Between July 2021 and January 2022, we collected the large-scale testing information and case number of imported COVID-19 patients from the website of the National Health Commission of China. A compartment model was developed to identify the level of vaccine coverage that would allow safe relaxation of NPIs, and vaccination strategies that can best achieve this level of coverage. We applied Monte Carlo simulation 50 000 times to remove random fluctuation effects and obtain fitted/predicted epidemic curve based on various parameters with 95% confidence interval at each time point. RESULTS: We found that a vaccination coverage of 50.4% was needed for the safe relaxation of NPIs, if the vaccine effectiveness was 79.3%. The total number of incidence cases under the key groups firstly strategy was 103 times higher than that of accelerated vaccination strategy. It needed 35 months to fully relax NPIs if the key groups firstly strategy was implemented, and 27 months were needed with the accelerated vaccination strategy. If combined the two strategies, only 8 months are needed to achieve the vaccine coverage threshold for the fully relaxation of NPIs. Sensitivity analyses results shown that the higher the transmission rate of the virus and the lower annual vaccine supply, the more difficult the epidemic could be under control. When the transmission rate increased 25% or the vaccination effectiveness rate decreased 20%, 33 months were needed to reduce the number of total incidence cases below 1000. CONCLUSIONS: As vaccine coverage improves, the NPIs can be gradually relaxed. Until that threshold is reached, however, strict NPIs are still needed to control the epidemic. The more transmissible SARS-CoV-2 variant led to higher resurgence probability, which indicates the importance of accelerated vaccination and achieving the vaccine coverage earlier.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Vacunación
18.
Front Microbiol ; 13: 1041774, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36590439

RESUMEN

Background: Glaesserella parasuis causes Glässer's disease, which is associated with severe polyarthritis, fibrinous polyserositis and meningitis, and leads to significant economic losses to the swine industry worldwide. IgA is one of the most important humoral immune factors present on mucosal surfaces, and it plays a crucial role in neutralizing and removing pathogens. G. parasuis is able to colonize the mucosal membrane of respiratory tract without being eliminated. Nevertheless, the immune evasion mechanism of G. parasuis in thwarting IgA remains unclear. Aims: The object of this study is to characterize the IgA degradation activity of Mac-1-containing autotransporter EspP1 and EspP2 from G. parasuis. Methods: The swine IgA was purified and incubated with EspP1 and EspP2 respectively. Western blotting was used to detect the cleavage of swine IgA. Generation of EspP1 and EspP2 mutant protein were used to explore the putative active sites of EspPs. LC-MS/MS based N/C-terminal sequencing was performed to measure the cleavage sites in swine IgA. Result: Our results show that G. parasuis EspP1 and EspP2 cleave swine IgA in a dose- and time- dependent manner. G. parasuis lose the IgA protease activity after simultaneously delete espP1 and espP2 indicating that EspP1 and EspP2 are the only two IgA proteases in G. parasuis. The IgA protease activity of EspP1 and EspP2 is affected by the putative active sites which contain Cys47, His172 and Asp194/195. Swine IgA is cleaved within Cα1 and Cα3 domains upon incubation with EspPs. Moreover, EspPs can degrade neither IgG nor IgM while G. parasuis possess the ability to degrade IgM unexpectedly. It suggests that G. parasuis can secrete other proteases to cleave IgM which have never been reported. Conclusion: We report for the first time that both EspP1 and EspP2 are novel IgA-specific proteases and cleave swine IgA within the Cα1 and Cα3 domains. These findings provide a theoretical basis for the EspPs-induced immune evasion.

19.
Cities ; 120: 103439, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34539020

RESUMEN

The outbreak of novel coronavirus disease 2019 (COVID-19) has brought great challenges to the improvement of global smart city services. To date, few studies have been conducted on the effects of service quality on citizen engagement in smart cities in a public emergency. Based on the stimulus-organism-response (SOR) model and uncertain management theory, this study analyses the impact of the service quality of smart city system on citizen engagement in a public emergency. Data were collected in Chinese smart cities. Three valuable and novel results are identified. First, high-quality information content, highly reliable systems and highly responsive systems have a significant positive effect on citizens' continuous experiences, but not on citizens' immediate experiences. Second, both the immediate and continuous experiences of citizens have a significant positive effect on citizen engagement. Third, continuous experiences impose a full mediation effect between information content and citizen engagement, between reliability and citizen engagement and between responsiveness and citizen engagement. As its main contribution, this study focuses on the construction of a theoretical model. Based on this model, smart city managers can understand citizens' reactions in public emergencies from stimulation to experience and their behaviours in relation to smart city services.

20.
Hum Vaccin Immunother ; 17(12): 4954-4963, 2021 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-34893013

RESUMEN

Vaccination for the novel coronavirus disease 2019 (COVID-19) provides an effective approach for the general improvement of social safety and individual health. However, given that the current COVID-19 vaccine can only work for a period of time, the continuous vaccination of the vaccine will be particularly important. Using the Health Action Process Approach (HAPA) Model, Expectation Confirmation Model (ECM) and vaccine hesitancy (VH) theory, this research evaluates the continuous vaccination for COVID-19. This research selected Chinese survey platform to recruit respondents and conducted online surveys. A total of 768 Chinese individuals who were vaccinated participated in the survey, and 561 responses were effective after screening. Six valuable and novel findings are identified through this research. First, perceived efficacy has a positive significant impact on vaccination intention, but the positive effects of outcome expectancy and risk perception on vaccination intention are not significant. Second, social positive cues play a significant role in promoting vaccination intention. Third, VH has a negative significant influence on vaccination intention. Fourth, vaccination behavior produces a positive significant effect on perceived usefulness and satisfaction, respectively. Fifth, perceived usefulness exerted a positive significant impact on satisfaction and continuous vaccination, respectively. Sixth, satisfaction has no positive significant influence on continuous vaccination. Our theoretical model, which is the main contribution of this research, indicates that individual continuous vaccination is a process from motivation to intention, and from intention to behavior, and then from behavior to continuous vaccination.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , COVID-19/prevención & control , China/epidemiología , Estudios Transversales , Humanos , Intención , SARS-CoV-2 , Vacunación
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