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1.
Vaccine ; 42(12): 3075-3083, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38584060

RESUMO

As the major outer membrane protein (OMP) presents in the Pasteurella multocida envelope, OmpH was frequently expressed for laboratory assessments of its immunogenicity against P. multocida infections, but the results are not good. In this study, we modified OmpH with dendritic cell targeting peptide (Depeps) and/or Salmonella FliCd flagellin, and expressed three types of recombinant proteins with the MBP tag (rDepeps-FliC-OmpH-MBP, rDepeps-OmpH-MBP, rFliC-OmpH-MBP). Assessments in mouse models revealed that vaccination with rDepeps-FliC-OmpH-MBP, rDepeps-OmpH-MBP, or rFliC-OmpH-MBP induced significant higher level of antibodies as well as IFN-γ and IL-4 in murine sera than vaccination with rOmpH-MBP (P < 0.5). Vaccination with the three modified proteins also provided increased protection (rDepeps-FliC-OmpH-MBP, 70 %; rDepeps-OmpH-MBP, 50 %; rFliC-OmpH-MBP, 60 %) against P. multocida serotype D compared to vaccination with rOmpH-MBP (30 %). In mice vaccinated with different types of modified OmpHs, a significantly decreased bacterial strains were recovered from bloods, lungs, and spleens compared to rOmpH-MBP-vaccinated mice (P < 0.5). Notably, our assessments also demonstrated that vaccination with rDepeps-FliC-OmpH-MBP provided good protection against infections caused by a heterogeneous group of P. multocida serotypes (A, B, D). Our above findings indicate that modification with DCpep and Salmonella flagellin could be used as a promising strategy to improve vaccine effectiveness.


Assuntos
Infecções por Pasteurella , Pasteurella multocida , Animais , Camundongos , Sorogrupo , Infecções por Pasteurella/prevenção & controle , Flagelina/metabolismo , Proteínas da Membrana Bacteriana Externa , Peptídeos/metabolismo , Células Dendríticas , Vacinas Bacterianas
2.
Vet Microbiol ; 292: 110046, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38471428

RESUMO

Pasteurella multocida is a leading cause of respiratory disorders in pigs. However, the genotypes and antimicrobial resistance characteristics of P. multocida from pigs in China have not been reported frequently. In this study, we investigated 381 porcine strains of P. multocida collected in China between 2013 and 2022. These strains were assigned to capsular genotypes A (69.55%, n = 265), D (27.82%, n =106), and F (2.62%, n = 10); or lipopolysaccharide genotypes L1 (1.31%, n = 5), L3 (24.41%, n = 93), and L6 (74.28%, n = 283). Overall, P. multocida genotype A:L6 (46.46%) was the most-commonly identified type, followed by D:L6 (27.82%), A:L3 (21.78%), F:L3 (2.62%), and A:L1 (1.31%). Antimicrobial susceptibility testing showed that a relatively high proportion of strains were resistant to tetracycline (66.67%, n = 254), and florfenicol (35.17%, n = 134), while a small proportion of strains showed resistance phenotypes to enrofloxacin (10.76%, n = 41), ampicillin (8.40%, n = 32), tilmicosin (7.09%, n = 27), and ceftiofur (2.89%, n = 11). Notably, Illumina short-read and Nanopore long-read sequencing identified a chromosome-borne tigecycline-resistance gene cluster tmexCD3-toprJ1 in P. multocida. The structure of this cluster was highly similar to the respective structures found in several members of Proteus or Pseudomonas. It is assumed that the current study identified the tmexCD3-toprJ1 cluster for the first time in P. multocida.


Assuntos
Infecções por Pasteurella , Pasteurella multocida , Doenças dos Suínos , Suínos , Animais , Pasteurella multocida/genética , Tigeciclina/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Enrofloxacina , Família Multigênica , Infecções por Pasteurella/veterinária , Infecções por Pasteurella/tratamento farmacológico , Doenças dos Suínos/tratamento farmacológico
3.
Front Vet Sci ; 11: 1324768, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38384951

RESUMO

Proliferative enteropathy caused by Lawsonia intracellularis is an important economic associated disease to pig industry, but the knowledge about the prevalence of L. intracellularis in pig farms in China is limited. In addition, there is no complete genome sequence available for L. intracellularis isolates from China. In this study, we developed a TaqMan qPCR for the screening of L. intracellularis by targeting the bacterial 16S rDNA gene. Laboratory evaluations revealed a good sensitivity and specificity on detecting L. intracellularis nucleic acid. Using this method, we investigated 891 fecal samples from apparently healthy pigs in 47 farms. The results demonstrated a screening positive rate of 37.3% (95% CI, 34.1-40.5%) for the samples, and a farm screening positive rate of 93.6% (95% CI, 65.3-94.4%). The screening positive rate at herd level ranged from 6.67% (95% CI, 0.2-31.9%) to 40% (95% CI, 38-79.6%), while at animal level, the highest screening positive rate was found in 12-week-old pigs [85.7% (95% CI, 67.3-96.0%)]. Investigation of 705 diarrheal or bloody feces from symptomatic pigs revealed that the highest positive rate was found in replacement gilts which was 37.18% (95% CI, 45.1-89.5%). Secondly, we conducted the complete genome sequence of a L. intracellularis PPE-GX01-2022 from China through PacBio sequencing. The genome of PPE-GX01-2022 consisted of a chromosome of 1,439,110 bp in length and three plasmids of 193,063, 39,799, and 27,067 bp, respectively. This genome encoded 1,428 predicted proteins, 44 tRNAs, and 6 rRNAs. Sequence comparisons demonstrated that the genome sequence of PPE-GX01-2022 was highly homologous to those of two isolates from US, and these three isolates shared 1,378 core genes. The screening results suggest a high prevalence rate of L. intracellularis in Chinese pig farms. In addition, the genome sequence of the Chinese isolate was highly homologous to those of the field isolates from the US.

4.
Microbes Infect ; : 105235, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37802468

RESUMO

Two-component regulatory system (TCS) is a widespread bacterial signal transduction mechanism and plays a critical role in bacterial adaptation to environments as well as regulating bacterial virulence. However, few studies have reported the actions of TCS in Pasteurella multocida, a zoonotic bacterial pathogen. In this study, genes encoding proteins homologous to the ArcAB TCS were identified in genome sequences of P. multocida belonging to different serogroups, and the transcription of both arcA and arcB was up-regulated in anaerobic and superoxygen environment. Compared to wild type strains, P. multocida arcA-deletion mutants (ΔarcA) displayed a decrease in growing under anaerobic conditions, biofilm formation, as well as the capacities of anti-serum bactericidal effect, cell adherence and invasion, anti-phagocytosis, and virulence in different in vivo models (Galleria mellonella and mice). RNA-Seq identified 70 significantly downregulated genes in ΔarcA compared to the wild type strain, and several of them are associated with P. multocida virulence. Among them, a universal stress protein E encoding gene uspE was characterized in P. multocida for the first time. Electrophoretic mobility shift assay (EMSA) demonstrated that the ArcAB TCS could regulate uspE directly. Deletion of uspE also led to a decrease of P. multocida in growing under anaerobic conditions, biofilm formation, anti-serum bactericidal effect, cell adherence and invasion, anti-phagocytosis, and virulence in mice. The data provided from this study will help further understanding the fitness and pathogenesis of P. multocida.

5.
J Environ Public Health ; 2022: 8973525, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36213049

RESUMO

In order to better grasp the expression and translation methods of professional terms in the process of external reporting of public emergencies and grasp the characteristics and elements of the translation of publicity events, this study takes public emergencies as the research object and focuses on the application of English and Chinese professional terms and translation strategies in the process of external reporting. Therefore, based on the in-depth analysis of the news reporting framework of public health emergencies, this paper deeply summarizes the application skills of professional terms in publicity texts, so as to provide a certain reference for further improving the translator's ability to control the means of discourse cohesion and the level of discourse control of Chinese-English professional terms in the translation of public health events.


Assuntos
Emergências , Traduções , Humanos , Saúde Pública
6.
Int J Biol Sci ; 18(11): 4341-4356, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35864952

RESUMO

Background and aims: Vasoactive intestinal polypeptide type-I receptor (VIPR1) overexpression has been reported in numerous types of malignancies and utilized to develop novel target therapeutics and radiolabeled VIP analogue-based tumor imaging technology, but its role in liver carcinogenesis has not been explored. In the current study, we investigated the role of the VIP/VIPR1 signaling in controlling hepatocellular carcinoma (HCC) progression. Approach and results: By analyzing clinical samples, we found the expression level of VIPR1 was downregulated in human HCC tissues, which was correlated with advanced clinical stages, tumor growth, recurrence, and poor outcomes of HCC clinically. In vitro and in vivo studies revealed that activation of VIPR1 by VIP markedly inhibited HCC growth and metastasis. Intriguingly, transcriptome sequencing analyses revealed that activation of VIPR1 by VIP regulated arginine biosynthesis. Mechanistical studies in cultured HCC cells demonstrated that VIP treatment partially restored the expression of arginine anabolic key enzyme argininosuccinate synthase (ASS1), and to some extent, inhibited de novo pyrimidine synthetic pathway by downregulating the activation of CAD (carbamoyl-phosphate synthetase 2, aspartate transcarbamylase, and dihydroorotase). VIP treatment upregulated ASS1 and subsequently suppressed CAD phosphorylation in an mTOR/p70S6K signaling dependent manner. Clinically, we found human HCC samples were associated with downregulation of ASS1 but upregulation of CAD phosphorylation, and that VIPR1 levels positively correlated with ASS1 levels and serum levels of urea, the end product of the urea cycle and arginine metabolism in HCC. Conclusions: Loss of VIPR1 expression in HCC facilitates CAD phosphorylation and tumor progression, and restoration of VIPR1 and treatment with the VIPR1 agonist may be a promising approach for HCC treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Arginina/uso terapêutico , Argininossuccinato Sintase/metabolismo , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Humanos , Neoplasias Hepáticas/metabolismo , Pirimidinas/uso terapêutico , Receptores Tipo I de Polipeptídeo Intestinal Vasoativo , Ureia/uso terapêutico
7.
Pharmacogenomics ; 21(11): 751-759, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32615909

RESUMO

Background: Tumor-infiltrating lymphocytes (TILs) and postoperative chemotherapeutics interact in the tumor micro-environment. This interaction has not been well investigated in gastric cancer. Materials & methods: A total of 129 patients were divided into high or low TILs based on the median number of positive CD3+ and FoxP3+ T cells, which was assessed by immunocytochemistry. Results: Cox regression analysis showed that the stage III disease with shorter overall survival was significant. The analysis showed that high numbers of CD3+ or FoxP3+ T cells have better clinical outcomes in FOLFOX-treated patients. Conclusion: High CD3+ and FoxP3+ T-cell infiltration was associated with better clinical outcomes in patients with gastric cancer treated with FOLFOX, suggesting TILs incorporated into algorithms to improve the therapeutic efficacy of optimal chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/imunologia , Linfócitos do Interstício Tumoral/imunologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/imunologia , Microambiente Tumoral/imunologia , Adulto , Biomarcadores Tumorais/imunologia , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/imunologia , Humanos , Leucovorina/administração & dosagem , Leucovorina/imunologia , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/imunologia , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade , Taxa de Sobrevida/tendências , Resultado do Tratamento , Microambiente Tumoral/efeitos dos fármacos
8.
Clin Pharmacol Ther ; 108(3): 606-615, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32418204

RESUMO

Propranolol suppresses tumor growth in a variety of preclinical solid tumor models, with a number of proposed cell signaling and immunological mechanisms. We want to confirm the potential mechanisms, including reduced phosphorylation of AKT/MAPK pathways, as well as enhanced CD8+ T-cell-mediated antitumor immune response. To clarify the mechanism of propranolol activity in colorectal cancer, the therapeutic activity of propranolol was then assessed in CT26WT tumors engrafted in BALB/C mice. Then the effect of propranolol treatment was also examined by randomizing patients undergoing surgical resection of a previously untreated colorectal cancer to propranolol or placebo group and treated for 1 week prior to surgery. CT26WT tumor size was smaller after propranolol than vehicle control. Propranolol downregulated the expression of p-AKT/p-ERK/p-MEK in tumor tissue. The frequency of tumor CD8+ T cells was significantly elevated in propranolol-treated mice. The expression of GzmB/IFN-γ/T-bet in the CD8+ T-cell population was significantly increased in propranolol treated mice tumor tissue. In propranolol-treated surgical specimens, the expression of p-ERK was decreased and the frequency of CD8+ was significantly elevated. The expression of GzmB in the CD8+ T-cell population was significantly increased in propranolol-treated subjects. Together, these data show propranolol simultaneously activating autologous CD8+ T cells and decreasing the expression of p-AKT/p-ERK/p-MEK in mouse tumor models, while inhibiting the expression of p-ERK in clinical colorectal cancer. Effort is now needed to further dissect whether both pathways are required for antitumor effect, as the activity of this old drug is moved forward.


Assuntos
Antineoplásicos/uso terapêutico , Linfócitos T CD8-Positivos/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Ativação Linfocitária/efeitos dos fármacos , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Propranolol/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Adolescente , Adulto , Idoso , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Quimioterapia Adjuvante , China , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Feminino , Humanos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Terapia Neoadjuvante , Fosforilação , Transdução de Sinais , Fatores de Tempo , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Adulto Jovem
9.
Microb Pathog ; 141: 103978, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31953225

RESUMO

To investigate the effects of Bacillus methylotrophicus SY200 on Salmonella typhimurium (STM) infection in mice, a total of 36 three-week-old male mice were selected and randomly divided into 3 equal groups (N = 12). Group A and group B were fed with basal diet while group C was fed the basal diet supplemented with 0.1% (w/w) B. methylotrophicus SY200 during the 21 days experimental period. On the 14th day of the experiment, mice of group A were intragastrically administered with 0.5 ml of normal saline, group B and C were orally administered with 0.5 ml of STM suspension. On the first day and seventh day after STM challenge, the number of total white blood cells (WBCs) and neutrophils, relative weight of visceral organs, the number of Salmonella spp., Escherichia coli, Lactobacillus spp. and Bifidobacterium spp. in ileum and cecum, and diversity of cecal microflora were measured. The results showed that: on the first day and seventh day after STM challenge, the number of WBCs and neutrophils in the blood of the mice was the highest in group B, then followed by group C, and group A. On the first day after STM challenge, the relative weight of spleen in group C was significantly higher than that in group B (p < 0.05), moreover, compared with group B, B. methylotrophicus SY200 significantly reduced the number of Salmonella spp. and E. coli (p < 0.05), and increased the number of Lactobacillus spp. and Bifidobacterium spp. (p < 0.05) in the intestines of mice, and improved the Shannon-Wiener diversity (H), Simpson (E) and richness (S) indices of cecal flora of mice (p < 0.05). The results indicated that B. methylotrophicus SY200 could alleviate the inflammatory reaction after STM infection and resist the adverse effects of STM infection on mice intestinal flora.


Assuntos
Antibiose , Bacillus/fisiologia , Salmonelose Animal/microbiologia , Salmonella typhimurium/fisiologia , Ração Animal , Animais , Carga Bacteriana , Microbioma Gastrointestinal , Contagem de Leucócitos , Masculino , Metagenômica , Camundongos , Neutrófilos , Filogenia , Salmonelose Animal/sangue , Salmonelose Animal/prevenção & controle
10.
PLoS One ; 14(9): e0222223, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31513614

RESUMO

BACKGROUND: Hydronephrosis is a common finding in patients with bladder cancer. The aim of the study was to appraise the prognostic value of preoperative hydronephrosis in bladder cancer patients undergoing radical cystectomy. METHODS: We conducted a literature search using PubMed and Embase databases in Aug 2018. Summary hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated using fixed-effect or random-effects models. The primary endpoint was overall survival (OS). Secondary endpoints were cancer-specific survival (CSS) and recurrence-free survival (RFS). RESULTS: Overall, 13 studies published between 2008 and 2018 including 4,820 patients were selected for the meta-analysis. The age of bladder cancer patients ranged from 27 to 90.4 years, and the overall proportion of males was 72.5%. Preoperative hydronephrosis was reported in 27.4% of patients. The pooled HR was statistically significant for OS (HR, 1.36; 95% CI [1.20-1.55]) and CSS (HR, 1.64; 95% CI [1.33-2.02]), with no heterogeneity among the enrolled studies. Patients with bilateral hydronephrosis showed a poorer CSS compared to those with no hydronephrosis (HR 5.43, 95% CI [3.14-9.40]). However, there was no difference in CSS between no hydronephrosis and unilateral hydronephrosis groups (HR 1.35, 95% CI [0.84-2.14]). Despite a tendency towards poorer RFS (HR, 1.27; 95% CI [0.96-1.96]), the results demonstrated no significant association between presence of preoperative hydronephrosis and RFS after radical cystectomy. CONCLUSION: This meta-analysis indicates that preoperative hydronephrosis is significantly associated with poorer OS and CSS after radical cystectomy for patients with bladder cancer. Preoperative hydronephrosis has a stronger effect on CSS in patients with bilateral hydronephrosis. The presence of preoperative hydronephrosis not only predicts prognosis, but may also help to identify patients who benefit the most from neoadjuvant chemotherapy.


Assuntos
Hidronefrose/fisiopatologia , Neoplasias da Bexiga Urinária/complicações , Neoplasias da Bexiga Urinária/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cistectomia/métodos , Cistectomia/mortalidade , Feminino , Humanos , Hidronefrose/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Bexiga Urinária/patologia
11.
Sci Rep ; 7: 45405, 2017 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-28349995

RESUMO

The formation mechanism considers fivefold deformation twins originating from the grain boundaries in a nanocrystalline material, resulting in that fivefold deformation twins derived from a single crystal have not been reported by molecular dynamics simulations. In this study, fivefold deformation twins are observed in a single crystal of face-centered cubic (fcc) alloy. A new formation mechanism is proposed for fivefold deformation twins in a single crystal. A partial dislocation is emitted from the incoherent twin boundaries (ITBs) with high energy, generating a stacking fault along {111} plane, and resulting in the nucleating and growing of a twin by the successive emission of partials. A node is fixed at the intersecting center of the four different slip {111} planes. With increasing stress under the indentation, ITBs come into being close to the node, leading to the emission of a partial from the node. This generates a stacking fault along a {111} plane, nucleating and growing a twin by the continuous emission of the partials. This process repeats until the formation of fivefold deformation twins.

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