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1.
Int J Mol Sci ; 22(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34445577

RESUMO

Infections by the zoonotic foodborne bacterium Campylobacter jejuni (C. jejuni) are among the most frequent causes of bacterial gastroenteritis worldwide. The aim was to evaluate the relationship between epithelial barrier disruption, mucosal immune activation, and vitamin D (VD) treatment during C. jejuni infection, using intestinal epithelial cells and mouse models focused on the interaction of C. jejuni with the VD signaling pathway and VD treatment to improve C. jejuni-induced barrier dysfunction. Our RNA-Seq data from campylobacteriosis patients demonstrate inhibition of VD receptor (VDR) downstream targets, consistent with suppression of immune function. Barrier-preserving effects of VD addition were identified in C. jejuni-infected epithelial cells and IL-10-/- mice. Furthermore, interference of C. jejuni with the VDR pathway was shown via VDR/retinoid X receptor (RXR) interaction. Paracellular leakiness of infected epithelia correlated with tight junction (TJ) protein redistribution off the TJ domain and apoptosis induction. Supplementation with VD reversed barrier impairment and prevented inhibition of the VDR pathway, as shown by restoration of transepithelial electrical resistance and fluorescein (332 Da) permeability. We conclude that VD treatment restores gut epithelial barrier functionality and decreases bacterial transmigration and might, therefore, be a promising compound for C. jejuni treatment in humans and animals.


Assuntos
Infecções por Campylobacter/complicações , Permeabilidade da Membrana Celular , Células Epiteliais/efeitos dos fármacos , Interleucina-10/fisiologia , Mucosa Intestinal/efeitos dos fármacos , Vitamina D/farmacologia , Animais , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/isolamento & purificação , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Humanos , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Junções Íntimas/metabolismo , Vitaminas/farmacologia
2.
BMC Infect Dis ; 20(1): 518, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32677920

RESUMO

BACKGROUND: Campylobacter jejuni is a leading cause of bacterial diarrhea worldwide, and increasing rates of fluoroquinolone (FQ) resistance in C. jejuni are a major public health concern. The rapid detection and tracking of FQ resistance are critical needs in developing countries, as these antimicrobials are widely used against C. jejuni infections. Detection of point mutations at T86I in the gyrA gene by real-time polymerase chain reaction (RT-PCR) is a rapid detection tool that may improve FQ resistance tracking. METHODS: C. jejuni isolates obtained from children with diarrhea in Peru were tested by RT-PCR to detect point mutations at T86I in gyrA. Further confirmation was performed by sequencing of the gyrA gene. RESULTS: We detected point mutations at T86I in the gyrA gene in 100% (141/141) of C. jejuni clinical isolates that were previously confirmed as ciprofloxacin-resistant by E-test. No mutations were detected at T86I in gyrA in any ciprofloxacin-sensitive isolates. CONCLUSIONS: Detection of T86I mutations in C. jejuni is a rapid, sensitive, and specific method to identify fluoroquinolone resistance in Peru. This detection approach could be broadly employed in epidemiologic surveillance, therefore reducing time and cost in regions with limited resources.


Assuntos
Infecções por Campylobacter/diagnóstico , Campylobacter jejuni/genética , DNA Girase/genética , Farmacorresistência Bacteriana/genética , Fluoroquinolonas/uso terapêutico , Mutação Puntual , Reação em Cadeia da Polimerase em Tempo Real/métodos , Substituição de Aminoácidos , Infecções por Campylobacter/tratamento farmacológico , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/isolamento & purificação , Criança , Ciprofloxacina/uso terapêutico , Análise Mutacional de DNA/métodos , Diarreia/diagnóstico , Diarreia/tratamento farmacológico , Diarreia/microbiologia , Humanos , Isoleucina/genética , Testes de Sensibilidade Microbiana , Peru , Treonina/genética
3.
Sci Rep ; 9(1): 8931, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31222043

RESUMO

Campylobacter infections sourced mainly to poultry products, are the most important bacterial foodborne zoonoses worldwide. No effective measures to control these infections in broiler production exist to date. Here, we used passive immunization with hyperimmune egg yolks to confer broad protection of broilers against Campylobacter infection. Two novel vaccines, a bacterin of thirteen Campylobacter jejuni (C. jejuni) and C. coli strains and a subunit vaccine of six immunodominant Campylobacter antigens, were used for the immunization of layers, resulting in high and prolonged levels of specific immunoglobulin Y (IgY) in the hens' yolks. In the first in vivo trial, yolks (sham, bacterin or subunit vaccine derived) were administered prophylactically in the broiler feed. Both the bacterin- and subunit vaccine-induced IgY significantly reduced the number of Campylobacter-colonized broilers. In the second in vivo trial, the yolks were administered therapeutically during three days before euthanasia. The bacterin IgY resulted in a significant decrease in C. jejuni counts per infected bird. The hyperimmune yolks showed strong reactivity to a broad representation of C. jejuni and C. coli clonal complexes. These results indicate that passive immunization with hyperimmune yolks, especially bacterin derived, offers possibilities to control Campylobacter colonization in poultry.


Assuntos
Ração Animal , Anticorpos Antibacterianos/imunologia , Campylobacter jejuni/isolamento & purificação , Galinhas/microbiologia , Suplementos Nutricionais , Gema de Ovo/imunologia , Animais , Antígenos de Bactérias/imunologia , Campylobacter jejuni/crescimento & desenvolvimento , Campylobacter jejuni/imunologia , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Fezes/microbiologia , Imunização Passiva
4.
Microb Drug Resist ; 25(7): 1080-1086, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31021299

RESUMO

Aims: To determine the prevalence and the antibiotic resistance patterns of Campylobacter jejuni isolated from pediatric diarrhea patients in central Iran. Materials and Methods: Stool specimens (n = 230) were investigated using a modified Gram stain, two specific culture media, and C. jejuni-specific PCR. Antibiotic resistance profiles and relevant resistance genes were determined. Genetic relationships among a selection of the isolates were studied by Fla typing. Results: Out of the 230 diarrhea samples, 48 (20.8%) cases of C. jejuni were identified using modified Gram stain, 45 (19.5%) using the culture media, and 76 (33%) cases were identified using PCR. The highest antibiotic resistance rates were observed in 37 (82.2%) strains against tetracycline, in 32 (71.1%) against ciprofloxacin, and in 31 (68.8%) against erythromycin. Twenty (44.4%) isolates were resistant to ciprofloxacin and erythromycin simultaneously. Genotypic investigations found 36 (97.3%) strains carrying the tet (o) gene, 31 (96.8%) harboring the cmeB gene, 22 (68.7%) strains with the gyrA6 gene, 20 (64.5%) strains containing a 23S rRNA mutation, and 21 (65.6%) strains with the qnrS gene. Fla typing of a random subset of 14 strains revealed 11 different types showing the genomic diversity of the isolates. Strains sharing the same Fla type could be easily distinguished by their resistance gene profile. Conclusions: This is the first study to demonstrate that genetically diverse quinolone-macrolide-resistant C. jejuni is an important cause of gastroenteritis in children from central Iran. Pediatricians should consider these resistance features once the antibiotic prescription is necessary for prevention of possible complications, especially in those under 5 years of age. Of note, most cases of Campylobacter diarrhea are self-limiting and antibiotics should only be prescribed in those cases where severe complications evolve.


Assuntos
Infecções por Campylobacter/microbiologia , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/isolamento & purificação , Farmacorresistência Bacteriana/genética , Gastroenterite/microbiologia , Macrolídeos/uso terapêutico , Quinolonas/uso terapêutico , Antibacterianos/uso terapêutico , Infecções por Campylobacter/tratamento farmacológico , Campylobacter jejuni/genética , Criança , Pré-Escolar , Ciprofloxacina/uso terapêutico , Estudos Transversais , DNA Bacteriano/genética , Diarreia/tratamento farmacológico , Diarreia/microbiologia , Eritromicina/uso terapêutico , Feminino , Flagelina/genética , Gastroenterite/tratamento farmacológico , Genótipo , Humanos , Lactente , Irã (Geográfico) , Masculino , Testes de Sensibilidade Microbiana/métodos , RNA Ribossômico 23S/genética , Tetraciclina/uso terapêutico
5.
PLoS One ; 14(3): e0212946, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30845147

RESUMO

Campylobacter jejuni is a zoonotic agent responsible for the foodborne gastroenteritis campylobacteriosis. Control of C. jejuni load in the poultry primary production is recognized as an avenue to reduce human exposure to the pathogen. As for now, no commercially applicable control methods exist at the farm. Several studies tested egg yolk powders, potentiated or not against C. jejuni, as feed additives for chicken and suggested that the quantity and quality of the antibodies presence in the yolk are determinant factors for the full success of this approach. Unfortunately, data from these studies inconsistently showed a reduction of cecal C. jejuni carriage. Our first goal wwas to characterize (quantification by ELISA, agglutination test, bacterial antigen recognition profiles by Western blot, bactericidal effect by serum killing assays and C. jejuni mobility by soft agar migation) the antibodies extracted from egg yolk powders originating from different egg production protocols. Secondly, these powders were microencapsulated and recharacterized. Finally the protected powders were tested as a feed additive to destabilize C. jejuni colonization in an in vivo assay. Despite the in vitro results indicating the ability of the egg yolk powders to recognize Campylobacter and potentially alter its colonization of the chicken caecum, these results were not confirmed in the in vivo trial despite that specific caecal IgY directed toward Campylobacter were detected in the groups receiving the protected powders. More research is needed on Campylobacter in order to effectively control this pathogen at the farm.


Assuntos
Anticorpos Antibacterianos/imunologia , Infecções por Campylobacter/prevenção & controle , Campylobacter jejuni/imunologia , Gema de Ovo/imunologia , Aditivos Alimentares/administração & dosagem , Ração Animal , Animais , Anticorpos Antibacterianos/administração & dosagem , Antígenos de Bactérias/imunologia , Carga Bacteriana/efeitos dos fármacos , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/veterinária , Campylobacter jejuni/isolamento & purificação , Ceco/microbiologia , Galinhas/microbiologia , Composição de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Doenças Transmitidas por Alimentos/microbiologia , Doenças Transmitidas por Alimentos/prevenção & controle , Imunoglobulinas/administração & dosagem , Imunoglobulinas/imunologia , Produtos Avícolas/intoxicação , Pós , Resultado do Tratamento
7.
Foodborne Pathog Dis ; 14(6): 341-349, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28398869

RESUMO

The current trend in reducing the antibiotic usage in animal production imposes urgency in the identification of novel biocides. The essential oil carvacrol, for example, changes the morphology of the cell and acts against a variety of targets within the bacterial membranes and cytoplasm, and our in vitro results show that it reduces adhesion and invasion of chicken intestinal primary cells and also biofilm formation. A trial was conducted to evaluate the effects of dietary supplementation of carvacrol at four concentrations (0, 120, 200, and 300 mg/kg of diet) on the performance of Lactobacillus spp., Escherichia coli, Campylobacter spp., and broilers. Each of the four diets was fed to three replicates/trial of 50 chicks each from day 0 to 35. Our results show that carvacrol linearly decreased feed intake, feed conversion rates and increased body weight at all levels of supplementation. Plate count analysis showed that Campylobacter spp. was only detected at 35 days in the treatment groups compared with the control group where the colonization occurred at 21 days. The absence of Campylobacter spp. at 21 days in the treatment groups was associated with a significant increase in the relative abundance of Lactobacillus spp. Also, carvacrol was demonstrated to have a significant effect on E. coli numbers in the cecum of the treatment groups, at all supplementation levels. In conclusion, this study shows for the first time that at different concentrations, carvacrol can delay Campylobacter spp., colonization of chicken broilers, by inducing changes in gut microflora, and it demonstrates promise as an alternative to the use of antibiotics.


Assuntos
Infecções por Campylobacter/veterinária , Galinhas/microbiologia , Monoterpenos/farmacologia , Doenças das Aves Domésticas/prevenção & controle , Ração Animal/análise , Animais , Infecções por Campylobacter/prevenção & controle , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/isolamento & purificação , Ceco/efeitos dos fármacos , Ceco/microbiologia , Contagem de Colônia Microbiana , Cimenos , DNA Bacteriano/isolamento & purificação , Dieta/veterinária , Suplementos Nutricionais , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Ácidos Graxos/análise , Microbioma Gastrointestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Intestinos/microbiologia , Lactobacillus/efeitos dos fármacos , Lactobacillus/isolamento & purificação , Masculino , Doenças das Aves Domésticas/microbiologia , RNA Bacteriano/isolamento & purificação , RNA Ribossômico 18S/isolamento & purificação , Análise de Sequência de DNA , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
8.
Comp Med ; 67(1): 79-86, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28222842

RESUMO

As a growing threat to human and animal health, antimicrobial resistance (AMR) has become a central public-health topic. Largescale surveillance systems, such as the National Antimicrobial Resistance Monitoring System (NARMS), are now established to monitor and provide guidance regarding AMR, but comprehensive literature on AMR among NHP is sparse. This study provides data regarding current antimicrobial use strategies and the prevalence of AMR in zoonotic bacteria recovered from NHP within biomedical research institutions. We focused on 4 enteric bacteria: Shigella flexneri, Yersinia enterocolitica, Y. pseudotuberculosis, and Campylobacter jejuni. Fifteen veterinarians, 7 biomedical research institutions, and 4 diagnostic laboratories participated, providing susceptibility test results from January 2012 through April 2015. Veterinarians primarily treated cases caused by S. flexneri, Y. enterocolitica, and Y. pseudotuberculosis with enrofloxacin but treated C. jejuni cases with azithromycin and tylosin. All isolates were susceptible to the associated primary antimicrobial but often showed resistance to others. Specifically, S. flexneri isolates frequently were resistant to erythromycin (87.5%), doxycycline (73.7%), and tetracycline (38.3%); Y. enterocolitica isolates to ampicillin (100%) and cefazolin (93.6%); and C. jejuni isolates to methicillin (99.5%) and cephalothin (97.5%). None of the 58 Y. pseudotuber-culosis isolates was resistant to any tested antimicrobial. Notably, resistance patterns were not shared between this study's NHP isolates and human isolates presented by NARMS. Our findings indicate that zoonotic bacteria from NHP diagnostic samples are broadly susceptible to the antimicrobials used to treat the clinical infections. These results can help veterinarians ensure effective antimicrobial therapy and protect staff by minimizing occupational risk.


Assuntos
Antibacterianos/uso terapêutico , Infecções por Campylobacter/veterinária , Campylobacter jejuni/efeitos dos fármacos , Resistência Microbiana a Medicamentos , Infecções por Enterobacteriaceae/veterinária , Shigella flexneri/efeitos dos fármacos , Yersinia enterocolitica/efeitos dos fármacos , Yersinia pseudotuberculosis/efeitos dos fármacos , Animais , Infecções por Campylobacter/tratamento farmacológico , Infecções por Campylobacter/epidemiologia , Campylobacter jejuni/isolamento & purificação , Estudos Transversais , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/epidemiologia , Testes de Sensibilidade Microbiana/estatística & dados numéricos , Testes de Sensibilidade Microbiana/veterinária , Prevalência , Doenças dos Primatas , Primatas , Estudos Retrospectivos , Shigella flexneri/isolamento & purificação , Inquéritos e Questionários , Yersinia enterocolitica/isolamento & purificação , Yersinia pseudotuberculosis/isolamento & purificação , Zoonoses/tratamento farmacológico , Zoonoses/microbiologia
9.
Turk J Haematol ; 34(1): 93-98, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26377624

RESUMO

OBJECTIVE: Ankaferd hemostat (Ankaferd Blood Stopper®, ABS)-induced pharmacological modulation of essential erythroid proteins can cause vital erythroid aggregation via acting on fibrinogen gamma. Topical endoscopic ABS application is effective in the controlling of gastrointestinal (GI) system hemorrhages and/or infected GI wounds. Escherichia coli O157:H7, the predominant serotype of enterohemorrhagic E. coli, is a cause of both outbreaks and sporadic cases of hemorrhagic colitis. The aim of this study is to examine the effects of ABS on 6 different Shiga toxigenic E. coli serotypes including O26, O103, O104, O111, O145, and O157 and on other pathogens significant in foodborne diseases, such as Salmonella Typhimurium, Campylobacter jejuni, and Listeria monocytogenes, were also assessed. MATERIALS AND METHODS: All strains were applied with different amounts of ABS and antimicrobial effect was screened. S. Typhimurium groups were screened for survival using the fluorescence in situ hybridization technique. RESULTS: The relative efficacy of ABS solutions to achieve significant logarithmic reduction in foodborne pathogens E. coli O157:H7 and non-O157 serogroups and other emerging foodborne pathogens is demonstrated in this study. ABS has antibacterial effects. CONCLUSION: Our present study indicated for the first time that ABS may act against E. coli O157:H7, which is a cause of thrombotic thrombocytopenic purpura, hemolytic-uremic syndrome, and hemorrhagic colitis. The interrelationships between colitis, infection, and hemostasis within the context of ABS application should be further investigated in future studies.


Assuntos
Doenças Transmitidas por Alimentos/diagnóstico , Extratos Vegetais/química , Escherichia coli Shiga Toxigênica/isolamento & purificação , Campylobacter jejuni/isolamento & purificação , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Hibridização in Situ Fluorescente , Listeria monocytogenes/isolamento & purificação , Salmonella typhimurium/isolamento & purificação , Sorotipagem
10.
J Microbiol Immunol Infect ; 50(1): 75-82, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25683191

RESUMO

BACKGROUND: Campylobacter spp. are zoonotic pathogens, however, knowledge about their presence and antimicrobial resistance in nonhuman primates is limited. Our animal facility purchased cynomolgus monkeys (Macaca fascicularis) from various Asian countries: China, Cambodia, Indonesia, the Philippines, and Vietnam. METHODS: Colonization by Campylobacter spp. was investigated in 238 of the monkeys from 2009 to 2012 and antimicrobial susceptibility testing was carried out for these isolates. Furthermore, we eradicated these pathogens from these monkeys. RESULTS: Campylobacter spp. were isolated from 47 monkeys from three specific countries: China, Cambodia, and Indonesia, with respective isolation rates of 15%, 36%, and 67%. Two monkeys, which were each infected with Campylobacter jejuni and Campylobacter coli, showed clinical symptoms of diarrhea and bloody feces. In total, 41 isolates of C. coli and 17 isolates of C. jejuni were detected. Antimicrobial susceptibility varied: in the monkeys from China, erythromycin (ERY)-, tetracycline (TET)-, and ciprofloxacin-resistant C. coli, in the monkeys from Cambodia, amoxicillin-intermediate, TET- and ciprofloxacin-resistant C. coli and amoxicillin- and ciprofloxacin-resistant C. jejuni, and in the monkeys from Indonesia, ciprofloxacin-resistant C. coli and TET- and ciprofloxacin-resistant C. jejuni were common (>75%). Multiresistant isolates of C. coli were found in monkeys from all countries and multiresistant isolates of C. jejuni were found in monkeys from Indonesia. The eradication rate with azithromycin was comparable to that with gentamicin (GEN) by oral administration, and was higher than those with amoxicillin-clavulanic acid (AMC) and chloramphenicol (CHL). CONCLUSION: From the perspective of zoonosis, we should acknowledge multiresistant Campylobacter spp. isolated from the monkeys as a serious warning.


Assuntos
Antibacterianos/uso terapêutico , Infecções por Campylobacter/veterinária , Campylobacter coli/efeitos dos fármacos , Campylobacter jejuni/efeitos dos fármacos , Doenças dos Primatas/microbiologia , Animais , Antibacterianos/farmacologia , Infecções por Campylobacter/tratamento farmacológico , Infecções por Campylobacter/microbiologia , Campylobacter coli/isolamento & purificação , Campylobacter jejuni/isolamento & purificação , Farmacorresistência Bacteriana , Feminino , Macaca fascicularis , Masculino , Testes de Sensibilidade Microbiana , Doenças dos Primatas/tratamento farmacológico , Resultado do Tratamento
11.
Kansenshogaku Zasshi ; 90(3): 297-304, 2016 May.
Artigo em Japonês | MEDLINE | ID: mdl-27529964

RESUMO

There have been few coherent reports on extraintestinal infection or bacteremia caused by Campylobacter jejuni (C. jejuni) or C. coli in Japan. To clarify the clinical and microbiological characteristics of invasive infections caused by these two species, we retrospectively analyzed the records of patients from whom these pathogens had been isolated from sterile sites between 2000 and 2015. During this study period, we identified 9 patients. The clinical syndrome of all of these patients was bacteremia. Three patients had underlying diseases with both liver cirrhosis and malignant neoplasm, and all of these patients were aged 60 years or older. The remaining 6 patients were immunocompetent and younger than 40 years of age. All 9 patients had a fever of 38.5 degrees C or higher. The proportion of patients with gastrointestinal symptoms was lower for the 3 patients with underlying diseases, compared with the 6 patients without underlying diseases (1/3 cases vs, 4/6 cases). Of the 8 strains evaluated for antimicrobial susceptibility, all were susceptible to imipenem/cilastatin, kanamycin and erythromycin, and 2 were resistant to levofloxacin. Antimicrobial treatment was administered to 8 patients, but one spontaneously recovered without any treatment. We were able to follow the outcomes of 8 patients, and all of these patients completely recovered without relapses. We also reviewed 14 Japanese patients reported in the Japanese and English literature and found similar clinical features consisting of a high-grade fever and an association with underlying diseases and gastrointestinal symptoms. Of note, 3 agammaglobulinemic patients presented with bacteremia and extraintestinal infections and had multiple relapses. Based on the findings of our 9 cases and previous reports, the affected patients were divided into two groups according to clinical syndrome and therapeutic intervention. One group consisted of previously healthy children or young adults showing bacteremia. Most of them had enterocolitis complications but had a good prognosis. The other group consisted of patients with underlying diseases or elderly patients who presented with bacteremia alone or bacteremia with extraintestinal infections. The latter group, especially among those with humoral immunodeficiency, should be parentally treated with antimicrobial agents and requires careful monitoring for relapse. This is the largest case series study to examine invasive C. jejuni/coli infections in Japan, and it provides important epidemiological information on this rare infection.


Assuntos
Antibacterianos/uso terapêutico , Bacteriemia/microbiologia , Infecções por Campylobacter/tratamento farmacológico , Campylobacter jejuni/isolamento & purificação , Cilastatina/uso terapêutico , Imipenem/uso terapêutico , Adulto , Infecções por Campylobacter/diagnóstico , Criança , Pré-Escolar , Combinação Imipenem e Cilastatina , Combinação de Medicamentos , Feminino , Humanos , Japão , Masculino , Testes de Sensibilidade Microbiana/métodos , Pessoa de Meia-Idade , Adulto Jovem
13.
J Sci Food Agric ; 94(13): 2758-65, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24532379

RESUMO

BACKGROUND: Responsibility for food safety must be taken through the entire food-production chain, to avoid consumer cross-contamination. The antimicrobial activities of an Alpinia katsumadai seed extract and epigallocatechin gallate (EGCG), and their combination, were evaluated against individual food-borne pathogenic strains of Listeria monocytogenes, Escherichia coli and Campylobacter jejuni, individually and as a cocktail, in chicken-meat juice and sterile minced meat as food models, and in minced meat with the naturally present microflora, as an actual food sample. RESULTS: The antimicrobial combination of the A. katsumadai extract and EGCG was the most efficient for C. jejuni growth inhibition, followed by inhibition of L. monocytogenes, which was reduced more efficiently in the bacterial cocktail than as an individual strain. The antimicrobial combination added to minced meat at refrigeration temperatures used in the food chain (8 °C) revealed inhibition of these pathogens and inhibition of the naturally present bacteria after 5 days. CONCLUSIONS: The antibacterial efficiencies of the tested combinations are influenced by storage temperature. Food safety can be improved by using the appropriate combination of natural antimicrobials to reduce the microbiological risk of minced meat.


Assuntos
Alpinia/química , Antibacterianos/química , Manipulação de Alimentos , Conservantes de Alimentos/química , Carne/microbiologia , Compostos Fitoquímicos/química , Extratos Vegetais/química , Animais , Antioxidantes/química , Campylobacter jejuni/crescimento & desenvolvimento , Campylobacter jejuni/isolamento & purificação , Catequina/análogos & derivados , Catequina/química , Bovinos , Galinhas , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/isolamento & purificação , Armazenamento de Alimentos , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/isolamento & purificação , Carne/economia , Viabilidade Microbiana , Refrigeração , Sementes/química , Sus scrofa
14.
Appl Environ Microbiol ; 79(23): 7525-33, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24077703

RESUMO

Campylobacteriosis is the most frequent food-borne human enteritis. The major source for infection with Campylobacter spp. is broiler meat. Risk assessments consider the reduction of Campylobacter in primary production to be most beneficial for human health. The aim of this study was to test the efficacy of a bacteriophage application under commercial conditions which had proved to be effective in previous noncommercial studies under controlled experimental conditions. A phage cocktail for Campylobacter reduction was tested on three commercial broiler farms each with a control and an experimental group. Colonization of Campylobacter was confirmed prior to phage application in fecal samples. Subsequently, a phage cocktail was applied via drinking water in the experimental group (log10 5.8 to 7.5 PFU/bird). One day after phage application, Campylobacter counts of one experimental group were reduced under the detection limit (<50 CFU/g, P=0.0140) in fecal samples. At slaughter, a significant reduction of >log10 3.2 CFU/g cecal content compared to the control was still detected (P=0.0011). No significant reduction was observed in the experimental groups of the other trials. However, a significant drop in cecal Campylobacter counts occurred in a phage-contaminated control. These results suggest that maximum reduction of Campylobacter at the slaughterhouse might be achieved by phage application 1 to 4 days prior to slaughter.


Assuntos
Carga Bacteriana , Bacteriófagos/crescimento & desenvolvimento , Terapia Biológica/métodos , Infecções por Campylobacter/terapia , Infecções por Campylobacter/veterinária , Campylobacter jejuni/isolamento & purificação , Campylobacter jejuni/virologia , Infecções por Campylobacter/microbiologia , Portador Sadio/microbiologia , Portador Sadio/terapia , Portador Sadio/veterinária , Fezes/microbiologia , Resultado do Tratamento
15.
Braz. j. microbiol ; Braz. j. microbiol;44(3): 693-699, July-Sept. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-699801

RESUMO

Campylobacteriosis is a worldwide distributed zoonosis. One of the main virulence factors related to Campylobacter spp. in animals and humans is the cytolethal distending toxin (CDT), encoded by three adjacent genes (cdtA, cdtB, cdtC). The occurrence of Campylobacter spp. in samples of vegetables has not been reported in Brazil yet, and has seldom been described in the international literature. The detection of CDT in these strains has not been reported, either. The objectives of the present study were to determine the occurrence of Campylobacter spp. strains carrying virulence factors in samples of poultry and vegetables (lettuce and spinach) from different points of sale, thus verifying if vegetables are as an important vehicle for potentially virulent Campylobacter spp. strains as poultry. Twenty four strains were identified as Campylobacter jejuni by phenotypic and genotypic methods: 22 from broiler carcasses and two from lettuce samples. Three strains were identified as Campylobacter coli: two from broiler carcasses and one from lettuce. The presence of the cdt genes were detected in 20/24 (83.3%) C. jejuni strains, and 3/3 (100%) C. coli strains. The isolation of Campylobacter spp. strains with the cdt gene cluster in lettuce samples points to a new possible source of contamination, which could have an impact in the vegetable production chain and risk to public health. Results show that potentially virulent C. jejuni and C. coli strains remain viable in samples of broiler carcasses and vegetables at the points of sale.


Assuntos
Animais , Toxinas Bacterianas/genética , Campylobacter coli/isolamento & purificação , Campylobacter jejuni/isolamento & purificação , Galinhas/microbiologia , Lactuca/microbiologia , Spinacia oleracea/microbiologia , Fatores de Virulência/genética , Brasil , Campylobacter coli/classificação , Campylobacter coli/genética , Campylobacter jejuni/classificação , Campylobacter jejuni/genética , Prevalência
16.
Appl Environ Microbiol ; 78(5): 1624-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22210208

RESUMO

Modified charcoal-cefoperazone-deoxycholate agar (mCCDA) was improved by supplementation with a high concentration of polymyxin B. The ability of the supplemented medium to isolate Campylobacter jejuni and C. coli from chicken carcass rinses was compared to that of Campy-Cefex agar and mCCDA. Modification of mCCDA with increased polymyxin B yielded a significantly (P < 0.05) higher isolation rate and greater selectivity than those achieved using Campy-Cefex agar and mCCDA.


Assuntos
Técnicas Bacteriológicas , Campylobacter coli/isolamento & purificação , Campylobacter jejuni/isolamento & purificação , Meios de Cultura/química , Seleção Genética , Ágar , Animais , Cefoperazona/metabolismo , Carvão Vegetal/metabolismo , Galinhas , Ácido Desoxicólico/metabolismo , Polimixina B/metabolismo , Sensibilidade e Especificidade
17.
PLoS One ; 7(12): e51800, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23284770

RESUMO

BACKGROUND: Campylobacter is a major foodborne pathogen and alternative antimicrobials are needed to prevent or decrease Campylobacter contamination in foods or food producing animals. The objectives of this study are to define the anti-Campylobacter activities of natural phenolic compounds of plant origin and to determine the roles of bacterial drug efflux systems in the resistance to these natural phenolics in Campylobacter jejuni. METHODOLOGY/PRINCIPAL FINDINGS: Anti-Campylobacter activities were evaluated by an MIC assay using microdilution coupled with ATP measurement. Mutants of the cmeB and cmeF efflux genes and the cmeR transcriptional repressor gene were compared with the wild-type strain for their susceptibilities to phenolics in the absence and presence of efflux-pump inhibitors (EPIs). The phenolic compounds produced significant, but variable activities against both antibiotic-susceptible and antibiotic resistant Campylobacter. The highest anti-Campylobacter activity was seen with carnosic and rosmarinic acids in their pure forms or in enriched plant extracts. Inactivation of cmeB rendered C. jejuni significantly more susceptible to the phenolic compounds, while mutation of cmeF or cmeR only produced a moderate effect on the MICs. Consistent with the results from the efflux pump mutants, EPIs, especially phenylalanine-arginine ß-naphthylamide and NMP, significantly reduced the MICs of the tested phenolic compounds. Further reduction of MICs by the EPIs was also observed in the cmeB and cmeF mutants, suggesting that other efflux systems are also involved in Campylobacter resistance to phenolic compounds. CONCLUSION/SIGNIFICANCE: Natural phenolic compounds of plant origin have good anti-Campylobacter activities and can be further developed for potential use in controlling Campylobacter. The drug efflux systems in Campylobacter contribute significantly to its resistance to the phenolics and EPIs potentiate the anti-Campylobacter activities of plant phenolic compounds.


Assuntos
Antibacterianos/farmacologia , Infecções por Campylobacter/tratamento farmacológico , Campylobacter jejuni/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Abietanos/farmacologia , Animais , Antioxidantes/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/crescimento & desenvolvimento , Campylobacter jejuni/isolamento & purificação , Cinamatos/farmacologia , Depsídeos/farmacologia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Testes de Sensibilidade Microbiana , Fenóis/isolamento & purificação , Ácido Rosmarínico
18.
Eur J Intern Med ; 22(5): e60-2, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21925045

RESUMO

BACKGROUND: In the management of acute diarrhea, administration of antibiotics may be indicated. Appropriate antimicrobial therapy can shorten illness, reduce morbidity and can be life-saving in invasive infections. Emergence of microbial strains resistant to commonly used antibiotics means that treatment failures may become common. Because of changing patterns of resistance, knowledge of recent local patterns of susceptibility can guide the initial choice of antibiotics. METHODS: A retrospective study was conducted to investigate the epidemiology of infective gastroenteritis in patients over 14years old in the region of Chania (Crete). We reviewed all positive stool cultures and susceptibilities of the pathogens recovered from patients with symptoms of acute diarrhea, from 2003 until October 2010. RESULTS: Out of 194 positive stool cultures, we observed 139 cases of Salmonella enterica and 48 cases of Campylobacter jejuni. During the last 3years of observation there was an increased incidence of C. jejuni, especially after the tap water outbreak that occurred in our region in 2009. DISCUSSION: In the vast majority of acute diarrhea in adults, antibiotics are of no benefit and overprescription may confer to side effects, costs and emergence of resistance. Antibiotics are initiated in cases of febrile diarrheas especially those believed to have moderate to severe disease. Considering the increased incidence of C. jejuni and the resistance of the great majority of isolated strains to quinolones as well as the sensitivity of Salmonella spp. to azithromycin, administration of azithromycin empirically for acute diarrhea, when indicated, could be appropriate in our region.


Assuntos
Antibacterianos/uso terapêutico , Infecções por Campylobacter/tratamento farmacológico , Diarreia/tratamento farmacológico , Pesquisa Empírica , Gastroenterite/tratamento farmacológico , Guias de Prática Clínica como Assunto , Infecções por Salmonella/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções por Campylobacter/complicações , Infecções por Campylobacter/epidemiologia , Campylobacter jejuni/isolamento & purificação , Diarreia/epidemiologia , Diarreia/etiologia , Fezes/microbiologia , Feminino , Seguimentos , Gastroenterite/complicações , Gastroenterite/epidemiologia , Grécia/epidemiologia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Morbidade/tendências , Estudos Retrospectivos , Infecções por Salmonella/complicações , Infecções por Salmonella/epidemiologia , Salmonella enterica/isolamento & purificação , Resultado do Tratamento , Adulto Jovem
19.
Phytother Res ; 25(8): 1125-32, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21280113

RESUMO

Campylobacter jejuni is one of the most common bacterial causes of diarrhoea in the industrialized world, being associated with the occurrence of Guillain-Barré Syndrome, and inducing diseases partially through intestinal adherence. With increasing reports of C. jejuni drug resistance against standard antibiotics, investigations into antiadhesive agents for the prevention of bacterial infection are highly significant. Given the consumer-driven development towards holistic and integrative healthcare, research into additional anti-Campylobacter effects of herbal medicines that are already used for their beneficial effects on bowel and digestive functions is important. Twenty-one herbal extracts were screened for antiadhesive activity against C. jejuni using modifications of previously published antiadhesion assays. Antiadhesion effects with IC(50) values <3 mg/mL were obtained for seven ethanol plant extracts, with Zingiber officinale (ginger), Capsicum annum (cayenne) and Glycyrrhiza glabra (licorice) displaying the highest antiadhesion activity against C. jejuni (IC(50) : <0.1 mg/mL, 0.29 mg/mL and 0.65 mg/mL, respectively). Differences in antiadhesion activity were found for two different Echinacea species, with E. purpurea displaying significantly higher and dose dependent antiadhesion activity than E. angustifolia. No significant antiadhesion activity (IC(50) values >35 mg/mL) was found for Agrimonia eupatoria (agrimony), Andrographis paniculata (andrographis), Matricaria recutita (chamomile), Foeniculum vulgare (fennel), Filipendula ulmaria (meadowsweet) and Artemisia absinthium (wormwood) extracts. This study provides evidence for additional beneficial effects of marketed herbal medicines in gastrointestinal disorders.


Assuntos
Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Infecções por Campylobacter/tratamento farmacológico , Campylobacter jejuni/efeitos dos fármacos , Extratos Vegetais/farmacologia , Campylobacter jejuni/isolamento & purificação , Campylobacter jejuni/fisiologia , Células HT29 , Humanos , Plantas/química
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