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As an important component of the deep tunnel drainage system for dealing with urban waterlogging, the rotating stepped dropshaft has been proposed due to its small air entrainment. However, the hydraulic characteristics inside the shaft still need to be fully studied. In this study, the flow patterns, water velocity, and pressure in the rotating stepped dropshaft under different flow rates and geometric parameters were studied using a three-dimensional numerical model. The results show that increasing the central angle of the step and reducing the step height can both reduce the terminal velocity. A theoretical formula for predicting the terminal velocity was established and well validated. The connection between the shaft and the outlet pipe poses a severe threat to the structural safety due to alternating positive and negative pressures. Wall-attached swirling flow generates a circular high-pressure zone at the bottom of the dropshaft and the larger the flow rate, the greater the pressure gradient at the center of the bottom. By using the momentum theorem and considering the impact pressure range of the swirling flow, the shaft bottom pressure can be predicted reasonably well.
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Agua , Movimiento (Física)RESUMEN
Foot-and-mouth disease (FMD) is an acute zoonosis causes significant economic losses. Vaccines able to stimulate efficient protective immune responses are urgently needed. In this study, Escherichia coli-derived recombinant VP1 of serotype A and O FMD virus (FMDV) was conjugated to thermostable scaffold lumazine synthase (LS) or Quasibacillus thermotolerans encapsulin (QtEnc) using a robust plug-and-display SpyTag/SpyCatcher system to generate multimeric nanovaccines. These nanovaccines induced highly potent antibody responses in vaccinated mice. On day 14 after the first immunisation, antibody titres were approximately 100 times higher than those of monomer antigens. Both vaccines induced high and long-term IgG antibody production. Moreover, the QtEnc-VP1 nanovaccine induced higher antibody titres than the LS-VP1 nanovaccine. The nanovaccines also induced Th1-biased immune responses and higher levels of neutralising antibodies. These data indicated that FMDV nanovaccines generated by conjugating VP1 with a thermostable scaffold are highly immunogenic and ideal candidates for FMDV control in low-resource areas.
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Virus de la Fiebre Aftosa , Fiebre Aftosa , Vacunas Virales , Animales , Ratones , Nanovacunas , Anticuerpos Antivirales , Adyuvantes Inmunológicos , Inmunidad , Proteínas de la CápsideRESUMEN
Monkeypox (mpox) is a zoonotic disease caused by monkeypox virus (MPXV) of the orthopoxvirus genus. The emergence and global spread of mpox in 2022 was declared as a public health emergency by World Health Organization. This mpox pandemic alarmed us that mpox still threaten global public health. Live vaccines could be used for immunization for this disease with side effects. New alternative vaccines are urgently needed for this re-emerging disease. Specific antibody responses play key roles for protection against MPXV, therefore, vaccines that induce high humoral immunity will be ideal candidates. In the present study, we developed thermostable nanovaccine candidates for mpox by conjugating MPXV antigens with thermostable nanoscafolds. Three MPXV protective antigens, L1, A29, and A33, and the thermostable Aquafex aeolicus lumazine synthase (AaLS), were expressed in E. coli and purified by Ni-NTA methods. The nanovaccines were generated by conjugation of the antigens with AaLS. Thermal stability test results showed that the nanovaccines remained unchanged after one week storage under 37â and only partial degradation under 60â, indicating high thermostability. Very interesting, one dose immunization with the nanovaccine could induce high potent antibody responses, and two dose induced 2-month high titers of antibodes. In vitro virus neutralization test showed that nanovaccine candidates induced significantly higher levels of neutralization antibodies than monomers. These results indicated that the AaLS conjugation nanovaccines of MPXV antigens are highly thermostable in terms of storage and antigenic, being good alternative vaccine candidates for this re-emerging disease.
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Terapias Complementarias , Mpox , Humanos , Nanovacunas , Escherichia coli , Adyuvantes Inmunológicos , Anticuerpos , Antígenos Virales , Monkeypox virusRESUMEN
OBJECTIVE: Brucellosis is a common and neglected zoonotic infectious disease worldwide caused by Brucella. However, transboundary transmissions among countries, particularly those with high incidences, are seldom investigated. In the present study, by taking China and Mongolia as examples, we aim to identify transboundary transmission risk and driving factors of brucellosis along borders. METHODS: 167 brucellosis outbreak locations along the border between China and Mongolia were collected. Wildlife distribution and cross-border activities were mapped. Maximum entropy approach modeling was conducted to predict the potential risk of prevalence of brucellosis with meteorological factors, geographical environment, economic development, living habits et al. The accuracy of the models was assessed by the area under the receiver operating characteristic (ROC) curve (AUC), Kappa test, and correctly classified instances (CCI). RESULTS: The spatial model performed excellent predictive performance with the predictor variables of soils, pastures, goat density, mean precipitation of the wettest month, temperature seasonality, and population density, which with the contribution and permutation important in 27.2 %, 31.9; 23.3 %, 6.8; 18.0 %, 17.2; 11.2 %, 18.1; 10. 3 %, 15.2; 10.0 %, 10.8. The calculated AUC, SD, Kappa, and CCI are 0.870, 0.001, 0.882, and 0.883, respectively. The distribution map of brucellosis showed high-risk areas along the borders. CONCLUSIONS: Our study identified high-risk areas and the driving effect of brucellosis along the borders between China and Mongolia. Moreover, there is the possibility of cross-border wildlife activities in high-risk areas, which increases the risk of cross-border brucellosis transmission. The funding provides clues for cooperative prevention and control of brucellosis by reducing transboundary transmission.
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Brucelosis , Animales , Mongolia/epidemiología , Brucelosis/epidemiología , Brucelosis/etiología , Zoonosis/epidemiología , Brotes de Enfermedades , China/epidemiología , CabrasRESUMEN
Antigen delivery based on non-virus-like particle self-associating protein nanoscffolds, such as Aquifex aeolicus lumazine synthase (AaLS), is limited due to the immunotoxicity and/or premature clearance of antigen-scaffold complex resulted from triggering unregulated innate immune responses. Here, using rational immunoinformatics prediction and computational modeling, we screen the T epitope peptides from thermophilic nanoproteins with the same spatial structure as hyperthermophilic icosahedral AaLS, and reassemble them into a novel thermostable self-assembling nanoscaffold RPT that can specifically activate T cell-mediated immunity. Tumor model antigen ovalbumin T epitopes and the severe acute respiratory syndrome coronavirus 2 receptor-binding domain are loaded onto the scaffold surface through the SpyCather/SpyTag system to construct nanovaccines. Compared to AaLS, RPT -constructed nanovaccines elicit more potent cytotoxic T cell and CD4+ T helper 1 (Th1)-biased immune responses, and generate less anti-scaffold antibody. Moreover, RPT significantly upregulate the expression of transcription factors and cytokines related to the differentiation of type-1 conventional dendritic cells, promoting the cross-presentation of antigens to CD8+ T cells and Th1 polarization of CD4+ T cells. RPT confers antigens with increased stability against heating, freeze-thawing, and lyophilization with almost no antigenicity loss. This novel nanoscaffold offers a simple, safe, and robust strategy for boosting T-cell immunity-dependent vaccine development.
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Linfocitos T CD8-positivos , COVID-19 , Humanos , Inmunidad Celular , Linfocitos T Citotóxicos , Antígenos de NeoplasiasRESUMEN
Brucellosis is a typical zoonosis driven by various risk factors, including environmental ones. The present study aimed to explore the driving effect of environmental factors on human brucellosis in a high incidence rate area, which provides understanding and implications in mitigating disease transmission risk in a multi-system between the human-animal-environment interface for preventing and controlling brucellosis based on the One Health concept. Based on the monthly time series data of human brucellosis and environmental variables, a Seasonal Autoregressive Integrated Moving Average Model with explanatory variables (SARIMAX) was applied to assess the association between environmental indicators and human brucellosis incidence (IHB). The results indicated distinct seasonal fluctuation during the study duration, tending to climb from April to August. Atmospheric pressure, precipitation, relative humidity, mean temperature, sunshine duration, and normalized difference vegetation index significantly drive IHB. Moreover, the well-fitting and predicting capability were performed and assessed in the optimal model was the SARIMAX (0,1,1) (0,1,1)12 model with the normalized difference vegetation index (ß = 0.349, P = 0.036) and mean temperature (ß = 0.133, P = 0.046) lagged in 6 months, and the precipitation lagged in 1 month (ß = -0.090, P = 0.004). Our study suggests the association between environmental risk factors and human brucellosis infection, which can be contributed to mitigating the transmission risk in the environmental drivers in a multi-system interface through comprehensive prevention and intervention strategies based on the One Health concept.
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The myriad of posttranslational modifications (PTMs) of proteins that occur in all living cells are crucial to all kinds of biological processes. Brucella is an intracellular parasitic bacterium that can cause chronic diseases in both humans and livestock. To reveal the relationship between PTMs and the virulence and survival of Brucella, we described the first comprehensive multiple PTM-omics atlas of B. abortus 2308. Five PTMs involving lysine, namely 2-hydroxyisobutyrylation, succinylation, crotonylation, acetylation, and malonylation were identified. Nearly 2,000 modified proteins were observed, and these proteins took part in many biological processes, with a variety of molecular functions. In addition, we detected many significant virulence factors of Brucella among the modified proteins. 10 of the 15 T4SS effector proteins were detected with one or more PTMs. Moreover, abundant PTMs were detected in other typical virulence factors. Considering the role of PTMs in various biological processes of Brucella virulence and survival, we propose that the virulence of Brucella is associated with the PTMs of proteins. Taken together, this study provides the first global survey of PTMs in Brucella. This is a prospective starting point for further functional analysis of PTMs during the survival of Brucella in hosts, interpretation of the function of Brucella proteins, and elucidation of the pathogenic mechanism of Brucella.
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Since severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) began to spread in late 2019, laboratories around the world have widely used whole genome sequencing (WGS) to continuously monitor the changes in the viral genes and discovered multiple subtypes or branches evolved from SARS-CoV-2. Recently, several novel SARS-CoV-2 variants have been found to be more transmissible. They may affect the immune response caused by vaccines and natural infections and reduce the sensitivity to neutralizing antibodies. We analyze the distribution characteristics of prevalent SARS-CoV-2 variants and the frequency of mutant sites based on the data available from GISAID and PANGO by R 4.0.2 and ArcGIS 10.2. Our analysis suggests that B.1.1.7, B.1.351, and P.1 are more easily spreading than other variants, and the key mutations of S protein, including N501Y, E484K, and K417N/T, have high mutant frequencies, which may have become the main genotypes for the spread of SARS-CoV-2.
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COVID-19 , SARS-CoV-2 , Anticuerpos Antivirales , Humanos , Glicoproteína de la Espiga del CoronavirusRESUMEN
The diagnostic delays pose a huge challenge to human brucellosis (HB), which increases the risk of chronicity and complications with a heavy disease burden. This study aimed to quantify and identify the associated factors in the diagnostic delays to its prevention, reduction, and elimination. This study analyzed risk factors associated with the diagnostic delays in a cross-sectional study with data collected from Tongliao City, Inner Mongolia Autonomous Region of China. Diagnostic delays were defined with a cutoff of 30, 60, and 90 days. In different delay groups, risk factors of diagnostic delays were analyzed by univariate analysis and modeled by multivariate logistic regression analysis. A total of 14,506 cases were collected between January 1, 2005, and December 31, 2017, of which the median diagnostic delays was 29 days [interquartile range (IQR): 14-54 days]. Logistic regression analysis indicated that the older age category was associated with longer diagnostic delays across all groups. Longer diagnostic delays increase with age among three delay groups (p for trend <0.001). Occupation as herdsman was associated with shorter diagnostic delays in group 1 with 30 days [adjusted odds ratio (aOR), 0.890 (95% CI 0.804-0.986)]. Diagnostic delays was shorter in patients with brucellosis who were reported in CDC in all delay groups [aOR 0.738 (95% CI 0.690-0.790), 0.539 (95% CI 0.497-0.586), and 0.559 (95% CI 0.504-0.621)]. Pastoral/agricultural area was associated with shorter diagnostic delays in group 1 with 30 days [aOR, 0.889 (95%CI 0.831-0.951)] and group 3 with 90 days [aOR, 0.806 (95%CI 0.727-0.893)]. Stratified analysis showed that the older age category was associated with an increased risk of a long delay in both genders (p < 0.05). The older age group-to-youth group OR increased along with increased delay time (p for trend <0.001). Furthermore, the pastoral/agricultural area was associated with a shorter delay in males (p < 0.05). Delays exist in the diagnosis of HB. We should pay great attention to the risk factors of diagnostic delays, such as older population, non-herdsman, non-pastoral/agricultural area, non-disease prevention, and control agencies. Effective measures should shorten the diagnostic delays, achieve early detection, diagnosis, and treatment, and reduce the risk of HB's chronicity, complications, and economic burden.
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Brucelosis , Diagnóstico Tardío , Adolescente , Anciano , Brucelosis/diagnóstico , China/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Oportunidad RelativaRESUMEN
Clinical trials have previously assessed various therapies for renal cell carcinoma (RCC); however, there is currently a lack of direct comparisons between these therapies. The present study identified published studies on RCC through Web of Science, PubMed, EMBASE, Cochrane Library of Controlled Trials and Clinical trials.gov that were written in the English language and published by February 2019. The data were selected and extracted independently by two reviewers. Standard pair-wise meta-analyses were performed using Stata. Network meta-analyses were subsequently performed using WinBUGS (version 1.4.3). The primary outcome of the present study was progression-free survival (PFS). Secondary outcomes included overall survival (OS), objective response rate (ORR) and adverse events of various targeted therapies. The results were presented as cumulative odds ratio, hazard ratio, corresponding 95% confidence interval and the surface under the cumulative ranking curve, which was used to rank the probabilities and outcome of each treatment in RCC. A total of 31 eligible publications for 18 randomized controlled trials consisting of 11,498 participants were included in the present study. The network meta-analyses revealed that a combination of lenvantinib and everolimus ranked first out of 16 treatments in terms of PFS, OS and ORR (probability of 54.0, 53.4 and 61.0%, respectively).