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1.
PLoS One ; 19(4): e0291896, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38630759

RESUMO

Human salmonellosis cases are often caused by Salmonella serovars Enteritidis and Typhimurium and associated with the consumption of eggs and egg products. Many countries therefore implemented general surveillance programmes on pullet and layer farms. The identification of risk factors for Salmonella infection may be used to improve the performance of these surveillance programmes. The aims of this study were therefore to determine 1) whether local farm density is a risk factor for the infection of pullet and layer farms by Salmonella Enteritidis and Typhimurium and 2) whether the sampling effort of surveillance programmes can be reduced by accounting for this risk factor, while still providing sufficient control of these serovars. We assessed the importance of local farm density as a risk factor by fitting transmission kernels to Israeli surveillance data during the period from June 2017 to April 2019. The analysis shows that the risk of infection by serovars Enteritidis and Typhimurium significantly increased if infected farms were present within a radius of approximately 4 km and 0.3 km, respectively. We subsequently optimized a surveillance programme that subdivided layer farms into low and high risk groups based on the local farm density with and allowed the sampling frequency to vary between these groups. In this design, the pullet farms were always sampled one week prior to pullet distribution. Our analysis shows that the risk-based surveillance programme is able to keep the between-farm R0 of serovars Enteritidis and Typhimurium below 1 for all pullet and layer farms, while reducing the sampling effort by 32% compared to the currently implemented surveillance programme in Israel. The results of our study therefore indicate that local farm density is an important risk factor for infection of pullet and layer farms by Salmonella Enteritidis and Typhimurium and can be used to improve the performance of surveillance programmes.


Assuntos
Doenças das Aves Domésticas , Salmonelose Animal , Infecções por Salmonella , Animais , Feminino , Humanos , Fazendas , Galinhas , Salmonella enteritidis , Fatores de Risco , Salmonelose Animal/epidemiologia
2.
Open Vet J ; 14(1): 449-458, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38633146

RESUMO

Background: Avian salmonellosis is a group of diseases caused by bacteria from the genus Salmonella with a negative impact on poultry, particularly chickens. In addition, salmonellosis is a global food-borne infection. Aim: The aim of this study was to evaluate the effect of nano-emulsion difloxacin (NED) and commercial difloxacin (CD) water supplement on broiler's growth, feed intake, and body weight, weight gain, growth rate, feed conversion ratio (FCR), and mortality rate (MR). The antibiotic sensitivity was determined both in-vivo and in-vitro for NED against Salmonella enterica Serovar enteritidis in chickens. Methods: 1500 one-day of age chicks were grouped into five groups as follows: group 1 (G1) control negative group, G2 control positive group (infected and not treated), G3 (infected and treated with CD, and G4 and G5 (infected and treated with NED at different doses). Samples, including the intestine, liver, and spleen were collected. Agar well diffusion test and minimum inhibitory concentrations were adopted. Histopathological lesions on different tissues were studied. During 35 days of the experiment, the feed intake, growth rate, growth gain, FCR, and MR were recorded daily. In addition, a variety of analytical techniques including transmission electron microscopic analysis, dynamic light scattering, UV-visible spectroscopy, and zeta-potential analysis were applied to characterize NED. Results: The agar well diffusion test indicated that NED was in-vitro effective against S. enteritidis isolates than CD. The minimum inhibitory concentration was recorded as NED inhibited bacterial growth till well 8 at a concentration of 0.78 µg/ml; on the other hand, the CD inhibited bacterial growth till well 6 at a concentration of 0.62 µg/ml. Growth performance and MRs in the groups treated with NED are significantly reduced. Conclusion: Treatment of broiler's drinking water with NED at doses of 0.5 and 1 ml instead of pure CD was able to enforce a new perspective, antibacterial efficacy, enhancing the productive performance, and reducing the MRs of broilers.


Assuntos
Ciprofloxacina/análogos & derivados , Infecções por Salmonella , Salmonella enteritidis , Animais , Antibacterianos/farmacologia , Galinhas , Ágar/farmacologia
3.
Nat Commun ; 15(1): 3120, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600106

RESUMO

Salmonella utilizes a type 3 secretion system to translocate virulence proteins (effectors) into host cells during infection1. The effectors modulate host cell machinery to drive uptake of the bacteria into vacuoles, where they can establish an intracellular replicative niche. A remarkable feature of Salmonella invasion is the formation of actin-rich protuberances (ruffles) on the host cell surface that contribute to bacterial uptake. However, the membrane source for ruffle formation and how these bacteria regulate membrane mobilization within host cells remains unclear. Here, we show that Salmonella exploits membrane reservoirs for the generation of invasion ruffles. The reservoirs are pre-existing tubular compartments associated with the plasma membrane (PM) and are formed through the activity of RAB10 GTPase. Under normal growth conditions, membrane reservoirs contribute to PM homeostasis and are preloaded with the exocyst subunit EXOC2. During Salmonella invasion, the bacterial effectors SipC, SopE2, and SopB recruit exocyst subunits from membrane reservoirs and other cellular compartments, thereby allowing exocyst complex assembly and membrane delivery required for bacterial uptake. Our findings reveal an important role for RAB10 in the establishment of membrane reservoirs and the mechanisms by which Salmonella can exploit these compartments during host cell invasion.


Assuntos
Infecções por Salmonella , Salmonella typhimurium , Humanos , Salmonella typhimurium/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Infecções por Salmonella/microbiologia , Membrana Celular/metabolismo , Membranas/metabolismo , Células HeLa
5.
BMJ Case Rep ; 17(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538103

RESUMO

Infections with non-typhoidal salmonella (NTS) most commonly cause localised infections such as cutaneous abscesses in humans and are a leading source of foodborne illness. Here, we present a unique case of NTS Choleraesuis in a perianal abscess in an immunocompetent patient without any comorbidities.A woman in her late 40s was diagnosed with a perianal abscess with an unknown origin of infection. The patient has undergone an incision and drainage. Her pus culture and sensitivity report yielded Salmonella enterica serotype Choleraesuis. Then, the patient recovered after treatment with intravenous antibiotics and supportive treatment.We present an unusual case of S. enterica serotype Choleraesuis, which is rarely reported as a causative agent of perianal abscess in India. This case has been reported for its rarity in India.


Assuntos
Infecções por Salmonella , Salmonella enterica , Dermatopatias , Febre Tifoide , Feminino , Humanos , Abscesso/diagnóstico , Infecções por Salmonella/complicações , Infecções por Salmonella/diagnóstico , Infecções por Salmonella/tratamento farmacológico , Sorogrupo , Antibacterianos/uso terapêutico , Dermatopatias/tratamento farmacológico , Febre Tifoide/tratamento farmacológico
6.
BMJ Open ; 14(3): e080501, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38485477

RESUMO

BACKGROUND: Invasive non-typhoidal Salmonella (iNTS) disease is a significant health concern in sub-Saharan Africa. While our knowledge of a larger-scale variation is growing, understanding of the subnational variation in iNTS disease occurrence is lacking, yet crucial for targeted intervention. METHOD: We performed a systematic review of reported occurrences of iNTS disease in sub-Saharan Africa, consulting literature from PubMed, Embase and Web of Science published since 2000. Eligibility for inclusion was not limited by study type but required that studies reported original data on human iNTS diseases based on the culture of a normally sterile site, specifying subnational locations and the year, and were available as full-text articles. We excluded studies that diagnosed iNTS disease based on clinical indications, cultures from non-sterile sites or serological testing. We estimated the probability of occurrence of iNTS disease for sub-Saharan Africa on 20 km × 20 km grids by exploring the association with geospatial covariates such as malaria, HIV, childhood growth failure, access to improved water, and sanitation using a boosted regression tree. RESULTS: We identified 130 unique references reporting human iNTS disease in 21 countries published from 2000 through 2020. The estimated probability of iNTS occurrence grids showed significant spatial heterogeneity at all levels (20 km × 20 km grids, subnational, country and subregional levels) and temporal heterogeneity by year. For 2020, the probability of occurrence was higher in Middle Africa (0.34, 95% CI: 0.25 to 0.46), followed by Western Africa (0.33, 95% CI: 0.23 to 0.44), Eastern Africa (0.24, 95% CI: 0.17 to 0.33) and Southern Africa (0.08, 95% CI: 0.03 to 0.11). Temporal heterogeneity indicated that the probability of occurrence increased between 2000 and 2020 in countries such as the Republic of the Congo (0.05 to 0.59) and Democratic Republic of the Congo (0.10 to 0.48) whereas it decreased in countries such as Uganda (0.65 to 0.23) or Zimbabwe (0.61 to 0.37). CONCLUSION: The iNTS disease occurrence varied greatly across sub-Saharan Africa, with certain regions being disproportionately affected. Exploring regions at high risk for iNTS disease, despite the limitations in our data, may inform focused resource allocation. This targeted approach may enhance efforts to combat iNTS disease in more affected areas.


Assuntos
Malária , Infecções por Salmonella , Febre Tifoide , Humanos , Criança , Infecções por Salmonella/epidemiologia , Infecções por Salmonella/complicações , Salmonella , Malária/epidemiologia , África Subsaariana/epidemiologia
7.
Front Cell Infect Microbiol ; 14: 1347813, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38487353

RESUMO

Introduction: Different serovars of Salmonella enterica cause systemic diseases in humans including enteric fever, caused by S. Typhi and S. Paratyphi A, and invasive nontyphoidal salmonellosis (iNTS), caused mainly by S. Typhimurium and S. Enteritidis. No vaccines are yet available against paratyphoid fever and iNTS but different strategies, based on the immunodominant O-Antigen component of the lipopolysaccharide, are currently being tested. The O-Antigens of S. enterica serovars share structural features including the backbone comprising mannose, rhamnose and galactose as well as further modifications such as O-acetylation and glucosylation. The importance of these O-Antigen decorations for the induced immunogenicity and cross-reactivity has been poorly characterized. Methods: These immunological aspects were investigated in this study using Generalized Modules for Membrane Antigens (GMMA) as delivery systems for the different O-Antigen variants. This platform allowed the rapid generation and in vivo testing of defined and controlled polysaccharide structures through genetic manipulation of the O-Antigen biosynthetic genes. Results: Results from mice and rabbit immunization experiments highlighted the important role played by secondary O-Antigen decorations in the induced immunogenicity. Moreover, molecular modeling of O-Antigen conformations corroborated the likelihood of cross-protection between S. enterica serovars. Discussion: Such results, if confirmed in humans, could have a great impact on the design of a simplified vaccine composition able to maximize functional immune responses against clinically relevant Salmonella enterica serovars.


Assuntos
Infecções por Salmonella , Vacinas contra Salmonella , Salmonella enterica , Humanos , Animais , Camundongos , Coelhos , Antígenos O/genética , Salmonella enterica/genética , Salmonella typhimurium/genética , Sorogrupo , Imunidade , Modelos Animais , Vacinas contra Salmonella/genética
8.
Sci Rep ; 14(1): 5148, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429351

RESUMO

Colistin remains one of the last-resort therapies for combating infections caused by multidrug-resistant (MDR) Enterobacterales, despite its adverse nephro- and neuro-toxic effects. This study elucidates the mechanism of action of a non-antibiotic 4-anilinoquinazoline-based compound that synergistically enhances the effectiveness of colistin against Salmonella enterica. The quinazoline sensitizes Salmonella by deactivating intrinsic, mutational, and transferable resistance mechanisms that enable Salmonella to counteract the antibiotic impact colistin, together with an induced disruption to the electrochemical balance of the bacterial membrane. The attenuation of colistin resistance via the combined treatment approach also proves efficacious against E. coli, Klebsiella, and Acinetobacter strains. The dual therapy reduces the mortality of Galleria mellonella larvae undergoing a systemic Salmonella infection when compared to individual drug treatments. Overall, our findings unveil the potential of the quinazoline-colistin combined therapy as an innovative strategy against MDR bacteria.


Assuntos
Mariposas , Infecções por Salmonella , Animais , Colistina/farmacologia , Colistina/uso terapêutico , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Infecções por Salmonella/tratamento farmacológico , Testes de Sensibilidade Microbiana
9.
Microbiol Res ; 282: 127631, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38330818

RESUMO

Global emergence of multidrug-resistant (MDR) Salmonella enterica serovar Typhimurium is a continuing challenge for modern healthcare. However, the knowledge, regarding the epidemiology of salmonellosis caused by the monophasic variant S. 4,[5],12:i:- in hospitalized patients, is limited in China. To bridge this gap, we carried out a retrospective study to determine the antimicrobial resistance, trends, and risk factors of S. Typhimurium and S. 4,[5],12:i:- (n = 329) recovered from patients in Zhejiang province between 2011 and 2019. The results showed that 90.57% (298/329) of the isolates were MDR; among them, 48.94% (161/329) and 12.46% (41/329) were phenotypically resistant to cephalosporins and fluoroquinolones, respectively, which are the drugs of choice used to treat salmonellosis in clinics. Additionally, we observed a higher incidence of infections among the young population (<5 years old). Notably, the higher prevalence of ST34 (sequence type 34) isolates, especially after 2014, with MDR (57.05%, 170/298) phenotype, and incidence of ST34 isolates co-harbouring mcr-1 (mobile colistin resistance gene) and blaCTX-M-14 (ß-lactamase gene) suggest an association between STs and drug resistance. Together, the increasing prevalence of MDR ST34 calls for enhanced monitoring strategies to mitigate the spread and dissemination of MDR clones of S. Typhimurium and S. 4,[5],12:i-. Our study provides improved knowledge about non-typhoid Salmonella (NTS) infections, which could help in the effective recommendation of antimicrobials in hospitalized patients.


Assuntos
Intoxicação Alimentar por Salmonella , Infecções por Salmonella , Humanos , Pré-Escolar , Salmonella typhimurium/genética , Antibacterianos/farmacologia , Sorogrupo , Estudos Retrospectivos , Farmacorresistência Bacteriana/genética , Infecções por Salmonella/epidemiologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana Múltipla/genética
10.
Mol Immunol ; 168: 47-50, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38422886

RESUMO

Salmonella enteritis in poultry can result in reduced immune function, decreased growth rate, and increased mortality. Many farm salmonella strains have developed severe drug resistance and are less susceptible to multiple antibiotics. In the post-antibiotic era, it is of great significance to identify the mechanism of salmonella-induced enteritis in chicks to protect their health and ensure food safety. This article will elucidate the activation mechanism of NOD-like receptor protein 3 (NLRP3) inflammasomes in Salmonella enteritis and review the research on interventions targeting NLRP3 inflammasomes.


Assuntos
Enterite , Proteína 3 que Contém Domínio de Pirina da Família NLR , Piroptose , Infecções por Salmonella , Enterite/veterinária , Inflamassomos/metabolismo , Mucosa Intestinal/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas NLR , Infecções por Salmonella/genética , Infecções por Salmonella/metabolismo , Salmonella typhimurium , Animais , Galinhas/metabolismo , Galinhas/microbiologia
11.
Sci Data ; 11(1): 244, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413596

RESUMO

Infectious disease outbreaks transcend the medical and public health realms, triggering widespread panic and impeding socio-economic development. Considering that self-limiting diarrhoea of sporadic cases is usually underreported, the Salmonella outbreak (SO) study offers a unique opportunity for source tracing, spatiotemporal correlation, and outbreak prediction. To summarize the pattern of SO and estimate observational epidemiological indicators, 1,134 qualitative reports screened from 1949 to 2023 were included in the systematic review dataset, which contained a 506-study meta-analysis dataset. In addition to the dataset comprising over 50 columns with a total of 46,494 entries eligible for inclusion in systematic reviews or input into prediction models, we also provide initial literature collection datasets and datasets containing socio-economic and climate information for relevant regions. This study has a broad impact on advancing knowledge regarding epidemic trends and prevention priorities in diverse salmonellosis outbreaks and guiding rational policy-making or predictive modeling to mitigate the infringement upon the right to life imposed by significant epidemics.


Assuntos
Surtos de Doenças , Intoxicação Alimentar por Salmonella , Infecções por Salmonella , Humanos , China/epidemiologia , Coleta de Dados , Salmonella , Intoxicação Alimentar por Salmonella/epidemiologia , Infecções por Salmonella/epidemiologia , Revisões Sistemáticas como Assunto , Metanálise como Assunto
12.
Poult Sci ; 103(4): 103483, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38354474

RESUMO

Salmonella infection is a major concern in poultry production which poses potential risks to food safety. Our previous study confirmed that Lactiplantibacillus plantarum (LP) postbiotic exhibited a strong antibacterial capacity on Salmonella in vitro. This study aimed to investigate the beneficial effects and underlying mechanism of LP postbiotic on Salmonella-challenged broilers. A total of 240 one-day-old male yellow-feathered broilers were pretreated with 0.8% deMan Rogosa Sharpe (MRS) medium or 0.8% LP postbiotic (LP cell-free culture supernatant, LPC) in drinking water for 28 d, and then challenged with 1×109 CFU Salmonella enterica serovar Enteritidis (SE). Birds were sacrificed 3 d postinfection. Results showed that LPC maintained the growth performance by increasing body weight (BW), average daily gain (ADG), and average daily feed intake (ADFI) in broilers under SE challenge. LPC significantly attenuated SE-induced intestinal mucosal damage. Specifically, it decreased the intestinal injury score, increased villus length and villus/crypt, regulated the expression of intestinal injury-related genes (Villin, matrix metallopeptidase 3 [MMP3], intestinal fatty acid-binding protein [I-FABP]), and enhanced tight junctions (zona occludens-1 [ZO-1] and Claudin-1). SE infection caused a dramatic inflammatory response, as indicated by the up-regulated concentrations of interleukin (IL)-1ß, IL-6, TNF-α, and the downregulation of IL-10, while LPC pretreatment markedly reversed this trend. We then found that LPC inhibited the activation of NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome by decreasing the gene expression of Caspase-1, IL-lß, and IL-18. Furthermore, LPC suppressed NLRP3 inflammasome activation by inhibiting nuclear factor-kappa B (NF-κB) signaling pathway (the reduced levels of toll-like receptor 4 [TLR4], myeloid differentiation factor 88 [MyD88], and NF-κB). Finally, our results showed that LPC regulated gut microbiota by enhancing the percentage of Ligilactobacillus and decreasing Alistipes and Barnesiella. In summary, we found that LP postbiotic was effective to protect broilers against Salmonella infection, possibly through suppressing NLRP3 inflammasome and optimizing gut microbiota. Our study provides the potential of postbiotics on prevention of Salmonella infection in poultry.


Assuntos
Microbioma Gastrointestinal , Infecções por Salmonella , Masculino , Animais , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , NF-kappa B/metabolismo , Galinhas/metabolismo
13.
J Virol ; 98(3): e0147623, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38376991

RESUMO

The ability of virulent bacteriophages to lyse bacteria influences bacterial evolution, fitness, and population structure. Knowledge of both host susceptibility and resistance factors is crucial for the successful application of bacteriophages as biological control agents in clinical therapy, food processing, and agriculture. In this study, we isolated 12 bacteriophages termed SPLA phage which infect the foodborne pathogen Salmonella enterica. To determine phage host range, a diverse collection of Enterobacteriaceae and Salmonella enterica was used and genes involved in infection by six SPLA phages were identified using Salmonella Typhimurium strain ST4/74. Candidate host receptors included lipopolysaccharide (LPS), cellulose, and BtuB. Lipopolysaccharide was identified as a susceptibility factor for phage SPLA1a and mutations in LPS biosynthesis genes spontaneously emerged during culture with S. Typhimurium. Conversely, LPS was a resistance factor for phage SPLA5b which suggested that emergence of LPS mutations in culture with SPLA1a represented collateral sensitivity to SPLA5b. We show that bacteria-phage co-culture with SPLA1a and SPLA5b was more successful in limiting the emergence of phage resistance compared to single phage co-culture. Identification of host susceptibility and resistance genes and understanding infection dynamics are critical steps in the rationale design of phage cocktails against specific bacterial pathogens.IMPORTANCEAs antibiotic resistance continues to emerge in bacterial pathogens, bacterial viruses (phage) represent a potential alternative or adjunct to antibiotics. One challenge for their implementation is the predisposition of bacteria to rapidly acquire resistance to phages. We describe a functional genomics approach to identify mechanisms of susceptibility and resistance for newly isolated phages that infect and lyse Salmonella enterica and use this information to identify phage combinations that exploit collateral sensitivity, thus increasing efficacy. Collateral sensitivity is a phenomenon where resistance to one class of antibiotics increases sensitivity to a second class of antibiotics. We report a functional genomics approach to rationally design a phage combination with a collateral sensitivity dynamic which resulted in increased efficacy. Considering such evolutionary trade-offs has the potential to manipulate the outcome of phage therapy in favor of resolving infection without selecting for escape mutants and is applicable to other virus-host interactions.


Assuntos
Bacteriófagos , Microbiologia Ambiental , Salmonella enterica , Antibacterianos/uso terapêutico , Bacteriófagos/isolamento & purificação , Sensibilidade Colateral a Medicamentos , Lipopolissacarídeos , Salmonella enterica/virologia , Terapia por Fagos , Infecções por Salmonella/terapia , Humanos
14.
16.
J Agric Food Chem ; 72(8): 4301-4316, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38344988

RESUMO

This study optimized the menaquinone-7 (MK-7) synthetic pathways in Bacillus subtilis (B. subtilis) natto NB205, a strain that originated from natto, to enhance its MK-7 production. Utilizing mutation breeding, we developed NBMK308, a mutant strain that demonstrated a significant 117.23% increase in MK-7 production. A comprehensive transcriptome analysis identified two key genes, ispA and ispE, as being critical in MK-7 synthesis. The dual-sgRNA CRISPRa system was utilized to achieve precise regulation of ispA and ispE in the newly engineered strain, A3E3. This strategic modulation resulted in a significant enhancement of MK-7 production, achieving increases of 20.02% and 201.41% compared to traditional overexpression systems and the original strain NB205, respectively. Furthermore, the fermentation supernatant from A3E3 notably inhibited Salmonella invasion in Caco-2 cells, showcasing its potential for combating such infections. The safety of the dual-sgRNA CRISPRa system was confirmed through cell assays. The utilization of the dual-sgRNA CRISPRa system in this study was crucial for the precise regulation of key genes in MK-7 synthesis, leading to a remarkable increase in production and demonstrating additional therapeutic potential in inhibiting pathogenic infections. This approach effectively combined the advantages of microbial fermentation and biotechnology, addressing health and nutritional challenges.


Assuntos
Infecções por Salmonella , Alimentos de Soja , Humanos , Bacillus subtilis/metabolismo , RNA Guia de Sistemas CRISPR-Cas , Células CACO-2 , Fermentação , Infecções por Salmonella/prevenção & controle
17.
J Ethnopharmacol ; 325: 117864, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38325671

RESUMO

ETHNOPHARMACOLOGY RELEVANCE: Cananga oil (CO) is derived from the flowers of the traditional medicinal plant, the ylang-ylang tree. As a traditional antidepressant, CO is commonly utilized in the treatment of various mental disorders including depression, anxiety, and autism. It is also recognized as an efficient antibacterial insecticide, and has been traditionally utilized to combat malaria and acute inflammatory responses resulting from bacterial infections both in vitro and in vivo. AIM OF THE STUDY: The objective of this study is to comprehensively investigate the anti-Salmonella activity and mechanism of CO both in vitro and in vivo, with the expectation of providing feasible strategies for exploring new antimicrobial strategies and developing novel drugs. METHODS: The in vitro antibacterial activity of CO was comprehensively analyzed by measuring MIC, MBC, growth curve, time-killing curve, surface motility, biofilm, and Live/dead bacterial staining. The analysis of the chemistry and active ingredients of CO was conducted using GC-MS. To examine the influence of CO on the membrane homeostasis of Salmonella, we conducted utilizing diverse techniques, including ANS, PI, NPN, ONPG, BCECF-AM, DiSC3(5), and scanning electron microscopy (SEM) analysis. In addition, the antibacterial mechanism of CO was analyzed and validated through metabolomics analysis. Finally, a mouse infection model of Salmonella typhimurium was established to evaluate the toxic side effects and therapeutic effects of CO. RESULTS: The antibacterial effect of CO is the result of the combined action of the main chemical components within its six (palmitic acid, α-linolenic acid, stearic acid, benzyl benzoate, benzyl acetate, and myristic acid). Furthermore, CO disrupts the balance of purine metabolism and the tricarboxylic acid cycle (TCA cycle) in Salmonella, interfering with redox processes. This leads to energy metabolic disorders and oxidative stress damage within the bacteria, resulting in bacterial shock, enhanced membrane damage, and ultimately bacterial death. It is worth emphasizing that CO exerts an effective protective influence on Salmonella infection in vivo within a non-toxic concentration range. CONCLUSION: The outcomes indicate that CO displays remarkable anti-Salmonella activity both in vitro and in vivo. It triggers bacterial death by disrupting the balance of purine metabolism and the TCA cycle, interfering with the redox process, making it a promising anti-Salmonella medication.


Assuntos
Cananga , Infecções por Salmonella , Humanos , Animais , Camundongos , Ciclo do Ácido Cítrico , Infecções por Salmonella/tratamento farmacológico , Óleos de Plantas/farmacologia , Óleos de Plantas/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias , Homeostase , Purinas/farmacologia , Testes de Sensibilidade Microbiana
18.
J Food Prot ; 87(3): 100236, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38307462

RESUMO

Salmonella infections are a leading cause of bacterial food-borne illness worldwide. Infections are highly associated with the consumption of contaminated food, and in particular, chicken meat. The severity of Salmonella infections depends on the presence of antimicrobial resistance genes and virulence factors. While there are many studies which have investigated Salmonella strains isolated from postharvest chicken samples, there is a gap in our understanding of the genetic properties that influence the persistence of Salmonella in preharvest and in particular their makeup of antimicrobial resistance genes and virulence factors. We used whole genome sequencing and hierarchical clustering to characterize and classify the genetic diversity of Salmonella enterica isolates (n = 55) recovered from the litter of commercial broiler chicken raised in four colocated broiler houses of one integrated farm over three consecutive flocks. The chicken were raised under a newly adopted "No Antibiotics Ever" program, and copper sulfate was administered via drinking water. In-silico serovar prediction identified three S. enterica serovars: Enteritidis (n = 12), Kentucky (n = 40), and Senftenberg (n = 3). Antimicrobial susceptibility testing revealed that only one S. Kentucky isolate was resistant to streptomycin, while the remaining isolates were susceptible to all antibiotics tested. Metal resistance operons, including copper and silver, were identified chromosomally and on plasmids in serovar Senftenberg and Kentucky isolates, respectively, while serovar Enteritidis carried several virulence factors on plasmids. Serovar Kentucky isolates harboring metal resistance operons were the only Salmonella isolates recovered from the litter of third flock cohort. These results suggest that there might be environmental selection for Salmonella strains carrying plasmid-associated metal resistance and virulence genes, which could play a role in their persistence in litter.


Assuntos
Anti-Infecciosos , Infecções por Salmonella , Salmonella enterica , Animais , Humanos , Galinhas/microbiologia , Esterco , Salmonella/genética , Antibacterianos/farmacologia , Infecções por Salmonella/microbiologia , Fatores de Virulência/genética , Farmacorresistência Bacteriana Múltipla/genética
19.
Braz J Microbiol ; 55(1): 681-688, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38175356

RESUMO

Pork is one of the most commonly consumed meats, and its safety has always been a concern. Recently, safety incidents caused by chemical or biological contamination such as drug residues, heavy metals, and pathogenic microorganisms in pork have been reported, and the safety of pork is a cause for concern. Salmonella spp. is one of the important foodborne pathogens that threaten human health. Pork is a high-risk vector food for Salmonella spp. infection. The assessment of the safety risk of Salmonella spp. in pork is conducive to the prevention of related foodborne diseases. In this paper, risk assessment models for Salmonella spp. in meat were developed. The quantitative risk assessment model for Salmonella spp. based on the pork supply chain showed that the annual number of cases of salmonellosis due to pork consumption in China is approximately 27 per 10,000 males and 24 per 10,000 females. Sensitivity analysis showed that the main factors affecting the risk of Salmonella spp. in pork were the display temperature, display time, and Salmonella spp. contamination concentration in pork at the sale.


Assuntos
Carne de Porco , Carne Vermelha , Infecções por Salmonella , Animais , Suínos , Humanos , Salmonella/genética , Carne Vermelha/microbiologia , Carne de Porco/análise , Manipulação de Alimentos , Carne/microbiologia , Medição de Risco , China/epidemiologia , Microbiologia de Alimentos , Contaminação de Alimentos/análise
20.
PLoS Biol ; 22(1): e3002486, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38236896

RESUMO

Acute gastrointestinal infection with intracellular pathogens like Salmonella Typhimurium triggers the release of the proinflammatory cytokine interleukin 1ß (IL-1ß). However, the role of IL-1ß in intestinal defense against Salmonella remains unclear. Here, we show that IL-1ß production is detrimental during Salmonella infection. Mice lacking IL-1ß (IL-1ß -/-) failed to recruit neutrophils to the gut during infection, which reduced tissue damage and prevented depletion of short-chain fatty acid (SCFA)-producing commensals. Changes in epithelial cell metabolism that typically support pathogen expansion, such as switching energy production from fatty acid oxidation to fermentation, were absent in infected IL-1ß -/- mice which inhibited Salmonella expansion. Additionally, we found that IL-1ß induces expression of complement anaphylatoxins and suppresses the complement-inactivator carboxypeptidase N (CPN1). Disrupting this process via IL-1ß loss prevented mortality in Salmonella-infected IL-1ß -/- mice. Finally, we found that IL-1ß expression correlates with expression of the complement receptor in patients suffering from sepsis, but not uninfected patients and healthy individuals. Thus, Salmonella exploits IL-1ß signaling to outcompete commensal microbes and establish gut colonization. Moreover, our findings identify the intersection of IL-1ß signaling and the complement system as key host factors involved in controlling mortality during invasive Salmonellosis.


Assuntos
Interleucina-1beta , Infecções por Salmonella , Animais , Humanos , Camundongos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Neutrófilos/metabolismo , Infecções por Salmonella/metabolismo , Salmonella typhimurium/metabolismo , Virulência
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