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Inflammation is crucial in diseases, and proteins play a key role in the interplay between innate immunity and pathology. This review explores how proteomics helps understanding this relationship, focusing on diagnosis and treatment. We explore the dynamic innate response and the significance of proteomic techniques in deciphering the complex network of proteins involved in prevalent diseases, including infections, cancer, autoimmune and neurodegenerative disorders. Proteomics identifies key proteins in host-pathogen interactions, shedding light on infection mechanisms and inflammation. These discoveries hold promise for diagnostic tools, therapies, and vaccines. In cancer research, proteomics reveals innate signatures associated with tumor development, immune evasion, and therapeutic response. Additionally, proteomic analysis has unveiled autoantigens and dysregulation of the innate immune system in autoimmunity, offering opportunities for early diagnosis, disease monitoring, and new therapeutic targets. Moreover, proteomic analysis has identified altered protein expression patterns in neurodegenerative diseases like Alzheimer's and Parkinson's, providing insights into potential therapeutic strategies. Proteomics of the innate immune system provides a comprehensive understanding of disease mechanisms, identifies biomarkers, and enables effective interventions in various diseases. Despite still in its early stages, this approach holds great promise to revolutionize innate immunity research and significantly improve patient outcomes across a wide range of diseases.
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Doenças Neurodegenerativas , Proteômica , Humanos , Proteômica/métodos , Imunidade Inata , Fenômenos Fisiológicos Celulares , Biomarcadores/metabolismo , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/terapia , InflamaçãoRESUMO
The effective food processing technology is a key step in eliminating human noroviruses in foods mainly due to their stability in diverse environmental conditions. The aim of this study was to evaluate the effect of rising temperatures for inactivation of norovirus genogroup (G) II and murine norovirus 1 in samples of tomato sauce (72-74 °C for 1 min) and ground meat (100 °C for 30 min). Spiking experiments were carried out in triplicate using TRIzol® reagent method associated with quantitative polymerase chain reaction (qPCR) TaqMan™ system combined with previous free RNA digestion. Success rate and efficiency recoveries of both viruses as well limit of detection of a method for each matrix were also conducted. The heat treatment applied here proved to be efficient to reduce the burden of norovirus GII in a range of 1-4 log10 genomic copies per gram (percentage ranging from 0.45 to 104.54%) in both matrices. The experiments in this study showed that the results of norovirus GII and murine norovirus 1 in tomato sauce and ground meat tested during thermal treatments cannot be generalized to other food matrices, since there may be food-specific protective effects, as the presence of different components, that can interfere in virus inactivation. Studies using different food matrices reinforce the importance to investigate viruses' inactivation thermal processes in foods due to the resistance of these viruses to adverse conditions, contributing to food security in food virology.
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Norovirus , Animais , Manipulação de Alimentos , Genótipo , Temperatura Alta , Humanos , Carne , Camundongos , Norovirus/genética , Inativação de VírusRESUMO
In patients with severe forms of COVID-19, thromboelastometry has been reported to display a hypercoagulant pattern. However, an algorithm to differentiate severe COVID-19 patients from nonsevere patients and healthy controls based on thromboelastometry parameters has not been developed. Forty-one patients over 18 years of age with positive qRT-PCR for SARS-CoV-2 were classified according to the severity of the disease: nonsevere (NS, n = 20) or severe (S, n = 21). A healthy control (HC, n = 9) group was also examined. Blood samples from all participants were tested by extrinsic (EXTEM), intrinsic (INTEM), non-activated (NATEM) and functional assessment of fibrinogen (FIBTEM) assays of thromboelastometry. The thrombodynamic potential index (TPI) was also calculated. Severe COVID-19 patients exhibited a thromboelastometry profile with clear hypercoagulability, which was significantly different from the NS and HC groups. Nonsevere COVID-19 cases showed a trend to thrombotic pole. The NATEM test suggested that nonsevere and severe COVID-19 patients presented endogenous coagulation activation (reduced clotting time and clot formation time). TPI data were significantly different between the NS and S groups. The maximum clot firmness profile obtained by FIBTEM showed moderate/elevated accuracy to differentiate severe patients from NS and HC. A decision tree algorithm based on the FIBTEM-MCF profile was proposed to differentiate S from HC and NS. Thromboelastometric parameters are a useful tool to differentiate the coagulation profile of nonsevere and severe COVID-19 patients for therapeutic intervention purposes.
Assuntos
Coagulação Sanguínea , COVID-19/sangue , Tromboelastografia , Trombofilia/sangue , Adulto , Idoso , Algoritmos , COVID-19/complicações , COVID-19/diagnóstico , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/isolamento & purificação , Índice de Gravidade de Doença , Trombofilia/diagnóstico , Trombofilia/etiologia , Adulto JovemRESUMO
BACKGROUND: Since the beginning of the COVID-19 pandemic, the world's attention has been focused on better understanding the relation between the human host and the SARS-CoV-2 virus, as its action has led to hundreds of thousands of deaths. OBJECTIVE: In this context, we decided to study certain consequences of the abundant cytokine release over the innate and adaptive immune systems, inflammation, and hemostasis, comparing mild and severe forms of COVID-19. METHODS: To accomplish these aims, we will analyze demographic characteristics, biochemical tests, immune biomarkers, leukocyte phenotyping, immunoglobulin profile, hormonal release (cortisol and prolactin), gene expression, thromboelastometry, neutralizing antibodies, metabolic profile, and neutrophil function (reactive oxygen species production, neutrophil extracellular trap production, phagocytosis, migration, gene expression, and proteomics). A total of 200 reverse transcription polymerase chain reaction-confirmed patients will be enrolled and divided into two groups: mild/moderate or severe/critical forms of COVID-19. Blood samples will be collected at different times: at inclusion and after 9 and 18 days, with an additional 3-day sample for severe patients. We believe that this information will provide more knowledge for future studies that will provide more robust and useful clinical information that may allow for better decisions at the front lines of health care. RESULTS: The recruitment began in June 2020 and is still in progress. It is expected to continue until February 2021. Data analysis is scheduled to start after all data have been collected. The coagulation study branch is complete and is already in the analysis phase. CONCLUSIONS: This study is original in terms of the different parameters analyzed in the same sample of patients with COVID-19. The project, which is currently in the data collection phase, was approved by the Brazilian Committee of Ethics in Human Research (CAAE 30846920.7.0000.0008). TRIAL REGISTRATION: Brazilian Registry of Clinical Trials RBR-62zdkk; https://ensaiosclinicos.gov.br/rg/RBR-62zdkk. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/24211.
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Nowadays, there is a growing interest in biodegradable polymers-based materials due to their diverse application in the biomedical field. Most studied systems involve biocompatible micro and nanodevices, such as liposomes, dendrimer, micelles or polymeric nanogels. The use of Radiation Technology, specifically gamma radiation, to produce micro and nanogels raises the possibility to obtain higher purity products, an important feature for biomedical and pharmaceutical applications. The radio-induced synthesis, characterization, cytotoxicity evaluation, and immunological response of nanogels are described in this study. Nanogel synthesis was performed in the absence of oxygen using aqueous polyvinylpyrrolidone solutions. Crosslinking reactions were carried out at 25 °C in a gamma irradiation chamber with a 60Co source. Nanogels properties were analysed by Scanning Electron Microscopy, Attenuated Total Reflection-Fourier Transform Spectroscopy, Dynamic Light Scattering, and Viscosimetry. The cytotoxicity and immunological response were evaluated by MTT test and analysis of the neutrophil respiratory burst. The results showed that nanogels formation strongly depends on the total absorbed dose. The nanogels have an elliptical shape and their chemical structure is similar to the initial polymer. The nanogels are biocompatible and promote a low-intensity neutrophil activation, similar to the well-characterized biomaterial TiO2, suggesting their potential biomedical uses(AU)
En la actualidad existe un interés creciente en los materiales biodegradables basados en polímeros, debido a sus diversas aplicaciones en la esfera de la biomedicina. En la mayoría de los sistemas estudiados participan micro- y nanodispositivos biocompatibles, tales como liposomas, dendrímeros, micelas o nanogeles poliméricos. El uso de la tecnología de radiaciones, en particular de radiaciones gamma, para producir micro- y nanogeles, eleva la posibilidad de obtener productos de mayor pureza, un rasgo importante con vistas a su aplicación biomédica y farmacéutica. El estudio describe la síntesis radioinducida, caracterización, evaluación de la citotoxicidad y respuesta inmunológica de los nanogeles. La síntesis de los nanogeles se realizó en ausencia de oxígeno, usando soluciones acuosas de polivinilpirrolidona. Las reacciones de entrecruzamiento se realizaron a 25 ºC en cámara de irradiación gamma con una fuente de 60Co. Las propiedades de los nanogeles se analizaron mediante microscopía electrónica de barrido, espectroscopia por transformada de Fourier total atenuada, dispersión dinámica de luz y viscosimetría. La citotoxicidad y la respuesta inmunológica se evaluaron mediante prueba MTT y análisis del estallido respiratorio de neutrófilos. Los resultados muestran que la formación de nanogeles depende en gran medida de la dosis total absorbida. Los nanogeles tienen forma elíptica y su estructura química es similar a la del polímero inicial. Los nanogeles son biocompatibles y promueven una activación de neutrófilos de baja intensidad similar al bien caracterizado material TiO2, lo que sugiere usos biomédicos potenciales(AU)
Assuntos
Humanos , Masculino , Feminino , Raios gama/uso terapêutico , Nanogéis/normas , Testes Imunológicos de CitotoxicidadeRESUMO
Intestinal ischemia reperfusion injury (iIRI) is a severe clinical condition presenting high morbidity and mortality worldwide. Some of the systemic consequences of IRI can be prevented by applying ischemic preconditioning (IPC), a series of short ischemia/reperfusion events preceding the major ischemia. Although neutrophils are key players in the pathophysiology of ischemic injuries, neither the dysregulation presented by these cells in iIRI nor the protective effect of iIPC have their regulation mechanisms fully understood. Protein phosphorylation, as well as the regulation of the respective phosphatases and kinases are responsible for regulating a large number of cellular functions in the inflammatory response. Moreover, in previous work we found hydrolases and transferases to be modulated in iIR and iIPC, suggesting the possible involvement of phosphatases and kinases in the process. Therefore, in the present study, we analyzed the phosphoproteome of neutrophils from rats submitted to mesenteric ischemia and reperfusion, either submitted or not to IPC, compared to quiescent controls and sham laparotomy. Proteomic analysis was performed by multi-step enrichment of phosphopeptides, isobaric labeling, and LC-MS/MS analysis. Bioinformatics was used to determine phosphosite and phosphopeptide abundance and clustering, as well as kinases and phosphatases sites and domains. We found that most of the phosphorylation-regulated proteins are involved in apoptosis and migration, and most of the regulatory kinases belong to CAMK and CMGC families. An interesting finding revealed groups of proteins that are modulated by iIR, but such modulation can be prevented by iIPC. Among the regulated proteins related to the iIPC protective effect, Vamp8 and Inpp5d/Ship are discussed as possible candidates for control of the iIR damage.
Assuntos
Intestinos/patologia , Precondicionamento Isquêmico , Neutrófilos/metabolismo , Fosfoproteínas/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Proteínas Quinases/metabolismo , Proteômica , Traumatismo por Reperfusão/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Fosfopeptídeos/química , Fosfopeptídeos/metabolismo , Fosfoproteínas/química , Fosforilação , Domínios Proteicos , Proteoma/metabolismo , Ratos , Traumatismo por Reperfusão/patologia , Transdução de SinaisRESUMO
This study aimed to assess the microbiological quality of natural mineral waters commercialized in 20 L returnable packs in Brazil by investigating the presence of bacteria and viruses in packs with different manufacturing times (Tm). With this purpose, 99 water samples from 33 lots (n = 3/batch) of 15 brands, obtained from packs with three intervals of Tm, were analyzed. Total coliforms (16.2%), Pseudomonas aeruginosa (9.9%), sulphite-reducing Clostridium (5.0%) and Escherichia coli (2.0%) were detected but enterococci and norovirus GII not. Regarding brands, 11 (73.3%) presented unsatisfactory results for at least one of the lots analyzed. Pseudomonas aeruginosa analysis revealed six sequence types and strains were susceptible to all antibiotics tested and were able to produce biofilms. Human adenovirus (4) and norovirus GI (9) were also identified in nine samples randomly selected. Natural mineral waters commercialized in 20 L packs with Tm ≥ 2 years presented more microbiological contamination (P ≤ 0.012) than ones with a Tm of 0-1 year or a Tm of 1-2 years. These results suggest that the validity period of reusable 20 L packs should be reduced or that they can no longer be reused.
Assuntos
Bactérias/isolamento & purificação , Águas Minerais/microbiologia , Águas Minerais/virologia , Vírus/isolamento & purificação , Bactérias/classificação , Brasil , Fatores de Tempo , Microbiologia da ÁguaRESUMO
In recent years, the number of new antimicrobial drugs launched on the market has decreased considerably even though there has been an increase in the number of resistant microbial strains. Thus, antimicrobial resistance has become a serious public health problem. Amphibian skin secretions are a rich source of host defense peptides, which generally are cationic and hydrophobic molecules, with a broad-spectrum of activity. In this study, one novel multifunctional defense peptide was isolated from the skin secretion of the Chaco tree frog, Boana raniceps. Figainin 2 (1FLGAILKIGHALAKTVLPMVTNAFKPKQ28) is cationic and hydrophobic, adopts an α-helical structure in 50% (v/v) trifluoroethanol (TFE), and is thermally stable. This peptide exhibited activity against Gram-negative and Gram-positive pathogenic bacteria arboviruses, T. cruzi epimastigotes; however, it did not show activity against yeasts. Figainin 2 also showed antiproliferative activity on cancer cells, is moderately active on human erythrocytes, and activates the oxidative burst in human neutrophils.
Assuntos
Proteínas de Anfíbios/metabolismo , Anuros/metabolismo , Defensinas/metabolismo , Pele/metabolismo , Proteínas de Anfíbios/química , Proteínas de Anfíbios/farmacologia , Animais , Arbovírus/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Candida/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Defensinas/química , Defensinas/farmacologia , Hemólise/efeitos dos fármacos , Humanos , Neutrófilos/efeitos dos fármacos , Conformação Proteica em alfa-Hélice , Trypanosoma cruzi/efeitos dos fármacosRESUMO
Intestinal ischemia and reperfusion injury is a model system of possible consequences of severe trauma and surgery, which might result into tissue dysfunction and organ failure. Neutrophils contribute to the injuries preceded by ischemia and reperfusion. However, the mechanisms by which intestinal ischemia and reperfusion stimulate and activate circulating neutrophils is still not clear. In this work, we used proteomics approach to explore the underlying regulated mechanisms in Wistar rat neutrophils after ischemia and reperfusion. We isolated neutrophils from three different biological groups; control, sham laparotomy, and intestinal ischemia/reperfusion. In the workflow, we included iTRAQ-labeling quantification and peptide fractionation using HILIC prior to LC-MS/MS analysis. From proteomic analysis, we identified 2,045 proteins in total that were grouped into five different clusters based on their regulation trend between the experimental groups. A total of 417 proteins were found as significantly regulated in at least one of the analyzed conditions. Interestingly, the enzyme prediction analysis revealed that ischemia/reperfusion significantly reduced the relative abundance of most of the antioxidant and pro-survival molecules to cause more tissue damage and ROS production whereas some of the significantly up regulated enzymes were involved in cytoskeletal rearrangement, adhesion and migration. Clusters based KEGG pathways analysis revealed high motility, phagocytosis, directional migration, and activation of the cytoskeletal machinery in neutrophils after ischemia and reperfusion. Increased ROS production and decreased phagocytosis were experimentally validated by microscopy assays. Taken together, our findings provide a characterization of the rat neutrophil response to intestinal ischemia and reperfusion and the possible mechanisms involved in the tissue injury by neutrophils after intestinal ischemia and reperfusion.
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This study assessed the efficacy of Origanum vulgare L. essential oil (OVEO) and carvacrol in inhibiting the growth of Pseudomonas aeruginosa ATCC 9027, as well as the development of direct tolerance and cross-tolerance when this bacterium was challenged with sublethal amounts of these substances in a meat-based broth and in a meat model. OVEO and carvacrol at their minimum inhibitory concentrations (MICs), 1/2 MIC and 1/4 MIC decreased the viable cell counts of P. aeruginosa in meat-based broth. Direct tolerance or cross-tolerance was not induced after exposure of the assayed bacterial strain to sublethal amounts of OVEO or carvacrol in meat-based broth and in an artificially contaminated ground beef. Bacterial cells progressively subcultured in meat-based broth with increasing amounts of the tested substances survived up to the MIC of OVEO and to 1/2 MIC of carvacrol. The results reveal a lack of induction of tolerance in P. aeruginosa by exposure to OVEO or carvacrol in meat-based broth and in a meat model.
Assuntos
Antibacterianos/farmacologia , Carne/microbiologia , Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Animais , Bovinos , Cimenos , Farmacorresistência Bacteriana , Microbiologia de Alimentos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Óleos Voláteis/químicaRESUMO
This work aimed to assess the clonal distribution among 94 strains of Staphylococcus aureus isolated from cow's milk, raw cheese, and a milking machine in 12 dairy farms in northeast Brazil, by analyzing different typing methods and detecting resistance and toxigenic profiles. For the first time, isolates of this region were assessed simultaneously by the polymorphism of the 3'-end coa gene and 16S-23S rDNA, pulsed-field gel electrophoresis, antibiotic resistance phenotyping, and toxigenic arsenal. Although pulsed-field gel electrophoresis patterns showed a wider variation (discriminatory index 0.83) than the PCR-based methods, the internal transcribed spacer-PCR proved to be a useful and inexpensive procedure for conducting epidemiological surveys of S. aureus on a regional scale. Each dairy farm had its own resistance profile, and in two herds, 63% of the strains were multiresistant, probably due to the indiscriminate use of antibiotics in bovine mastitis treatment. No methicillin-resistant S. aureus strains were detected in this study; however, 93.6% of S. aureus strains harbored variable profiles of staphylococcal enterotoxin genes seg, seh, sei, and sej. Transcriptional analysis revealed that 53.3% of staphylococcal enterotoxin genes actually transcribed, pointing out the food poisoning risk of these dairy products to consumers in the region. Based on the detection of the most prevalent clones in a herd or region, appropriate antibiotic therapy and specific immunization can be used for the treatment and control of staphylococcal mastitis.
Assuntos
Antibacterianos/farmacologia , Laticínios/microbiologia , Farmacorresistência Bacteriana , Leite/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Animais , Brasil , Bovinos , Contagem de Colônia Microbiana , Relação Dose-Resposta a Droga , Farmacorresistência Bacteriana Múltipla , Eletroforese em Gel de Campo Pulsado , Feminino , Contaminação de Alimentos/análise , Inocuidade dos Alimentos , Humanos , Mastite Bovina/diagnóstico , Mastite Bovina/tratamento farmacológico , Mastite Bovina/prevenção & controle , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Staphylococcus aureus/isolamento & purificaçãoRESUMO
This study aimed to evaluate whether sublethal concentrations of the essential oil of Origanum vulgare L. (OVEO) and its major compound carvacrol (CAR) cause injury to the cell membrane and outer membrane of Salmonella enterica serovar Typhimurium ATCC 14028 grown in a meat broth and to assess the effect of these substances on membrane fatty acid (FA) composition. Exposure of Salmonella Typhimurium ATCC 14028 to sublethal concentrations of OVEO or CAR caused damage to the cytoplasmic membrane and outer membrane. OVEO- and CAR-treated cells showed lower amounts of saturated FA than nontreated cells. Changes in membrane FA composition were mainly related to an increase of C16:1ω7c, C16:1ω7t, and C18:2ω6c, and to a decrease of C16:0, C17:0 cyclo, and C19:0 cyclo. These results indicate that exposure to sublethal concentrations of OVEO or CAR caused sublethal injury Salmonella Typhimurium ATCC 14028 and suggest that an adaptive response to these stresses is related to increased synthesis of unsaturated FA and cis-trans isomerization.
Assuntos
Produtos da Carne/microbiologia , Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Origanum/química , Extratos Vegetais/farmacologia , Salmonella typhimurium/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Cimenos , Ácidos Graxos/química , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Microbiologia de Alimentos , Reprodutibilidade dos Testes , Salmonella typhimurium/crescimento & desenvolvimentoRESUMO
The capacity of Origanum vulgare L. essential oil (OVEO) and its majority compound, carvacrol (CAR), to induce direct tolerance and cross-tolerance in Staphylococcus aureus against high temperature (45 °C), lactic acid (pH 5.2) and NaCl (10 g/100 mL) was assessed. Overnight exposure of S. aureus to sublethal concentrations (1/2 MIC, 1/4 MIC) of either OVEO or CAR in meat broth revealed no induction of direct protection. S. aureus cells pre-adapted to OVEO or CAR showed no induction of cross-protection to high temperature, lactic acid or NaCl. Cells subjected to 24 h cycles of adaptation in increasing amounts (1/2 MIC to 2 × MIC) of OVEO or CAR showed no increase in direct tolerance. These results revealed a lack of induction of direct protection or cross-protection in S. aureus exposed to sublethal amounts of OVEO or CAR in meat-based broth, as determined by monitoring cell survival and growth behavior.
Assuntos
Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Staphylococcus aureus/fisiologia , Adaptação Fisiológica , Carga Bacteriana , Meios de Cultura , Cimenos , Temperatura Alta , Concentração de Íons de Hidrogênio , Carne , Testes de Sensibilidade Microbiana , Viabilidade Microbiana , Origanum , Cloreto de Sódio/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimentoRESUMO
In this study, the inhibitory efficacy of Rosmarinus officinalis essential L. (ROEO) and 1,8-cineole (CIN) in inhibiting the growth and survival of Staphylococcus aureus ATCC 6538 and the induction of direct and bacterial cross protection (lactic acid pH 5.2; NaCl 100 g/L; high temperature 45°C) were evaluated following exposure to sublethal and increasing amounts of these treatments in meat broth. All of the concentrations of the ROEO and CIN examined in this study (minimum inhibitory concentration [MIC], 1/2 MIC, and 1/4 MIC) inhibited the viability of S. aureus throughout the 120 min of exposure. The overnight exposure of S. aureus to sublethal amounts of both ROEO or CIN in meat broth did not result in direct or cross protection. Cells progressively subcultured (24-h cycles) in meat broth with increasing amounts of ROEO or CIN showed no increased direct tolerance. These results reveal the antimicrobial efficacy of ROEO and CIN for use in food conservation systems as anti-S. aureus compounds given their efficacy at inhibiting bacterial growth, in addition to their lack of induction for the development of homologous and heterologous resistance.
Assuntos
Anti-Infecciosos/farmacologia , Cicloexanóis/farmacologia , Microbiologia de Alimentos , Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Rosmarinus/química , Staphylococcus aureus/efeitos dos fármacos , Eucaliptol , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Óleos de Plantas/farmacologia , Fatores de TempoRESUMO
Listeria monocytogenes has the capability of adapting to 1 or more antimicrobial compounds or procedures applied by the food industry to control the growth and survival of microorganisms in foods. In this study, the effects of Rosmarinus officinalis essential oil (EO) and the related compound 1,8-cineole on the inhibition of the growth and survival of L. monocytogenes ATCC 7644 were determined. The ability of the R. officinalis EO and 1,8-cineole to induce direct and cross-protection of bacteria against various stresses (lactic acid, pH 5.2; NaCl, 3 g/100 mL; high temperature, 45 °C) was also determined. At all concentrations tested (minimum inhibitory concentration (MIC), ½ MIC, and » MIC), both compounds inhibited the cell viability of L. monocytogenes over 120 min of exposure. Overnight exposure of L. monocytogenes to sublethal amounts of either the R. officinalis EO or 1,8-cineole in meat broth revealed no induction of direct or cross-protection against lactic acid, NaCl, or high temperature. Similarly, cells subjected to 24 h cycles of adaptation with increasing amounts (½ MIC to 2× MIC) of the EO and 1,8-cineole showed no increase in direct tolerance, as they were able to survive in growth medium containing up to ½ MIC of either substance. These results show the antimicrobial efficacy of R. officinalis EO and 1,8-cineole for use in systems, particularly as anti-L. monocytogenes compounds.
Assuntos
Cicloexanóis/farmacologia , Microbiologia de Alimentos , Listeria monocytogenes/efeitos dos fármacos , Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Rosmarinus/química , Anti-Infecciosos/farmacologia , Contagem de Colônia Microbiana , Eucaliptol , Carne/microbiologia , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacosRESUMO
Overnight exposure of Salmonella enterica serovar Typhimurium to sublethal amounts of Origanum vulgare essential oil (OV) and carvacrol (CAR) did not result in direct and cross-bacterial protection. Cells subcultured with increasing amounts of OV or CAR survived up to the MIC of either compound, revealing few significant changes in bacterial susceptibility.
Assuntos
Antibacterianos/farmacologia , Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Origanum/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/crescimento & desenvolvimento , Proteção Cruzada , Meios de Cultura , Cimenos , Humanos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana , Fatores de TempoRESUMO
The present study was carried out in 11 dairy herds in four municipal districts of the rural area of the State of Pernambuco, Brazil. Out of 984 quarter milk (246 cows), 10 (1.0 percent) were positive for clinical mastitis, 562 (57.1 percent) for subclinical mastitis and 412 (41.9 percent) were negative. A total of 81 Staphylococcus spp. isolates were obtained from milk samples from the cows diagnosed with subclinical mastitis. From these, 53 (65.0 percent) were S. aureus, 16 (20.0 percent) coagulase-positive staphylococci (CPS) and 12 (15.0 percent) coagulase-negative staphylococci (CNS). The isolates were further investigated for the presence of toxin genes by multiplex and uniplex PCR. The main gene observed was seg followed by seh, sei and sej. The distribution of these observed genes among the isolates obtained from different areas showed a regional pattern for the SEs. The presence of toxin genes in the strains isolated from bovine milk demonstrates a potential problem for public health.(AU)
O presente estudo foi realizado em 11 rebanhos leiteiros de quatro municípios da área rural do estado de Pernambuco, Brasil. Dos 984 quartos mamários examinados (246 vacas), 10 (1,0 por cento) foram positivos para a mastite clínica, 562 (57,1 por cento) para a mastite subclínica e 412 (41,9 por cento) foram negativos para mastite. Foram isoladas 81 linhagens de Staphylococcus spp. do leite de vacas com mastite subclínica. Destes, 53 (65,0 por cento) foram S. aureus, 16 (20,0 por cento) estafilococos coagulase-positivo (SCP) e 12 (15,0 por cento) estafilococos coagulase-negativo (SCN). O principal gene observado nos estafilococos foi o seg seguido pelo seh, sei e sej. Foi constatada distribuição regional dos genes dos estafilococos isolados dos animais nos municípios estudados. A presença dos genes das toxinas nas linhagens isoladas do leite de vacas representa risco potencial para a Saúde Pública.(AU)
Assuntos
Animais , Staphylococcus/isolamento & purificação , Staphylococcus/genética , Mastite Bovina , Leite , BovinosRESUMO
The present study was carried out in 11 dairy herds in four municipal districts of the rural area of the State of Pernambuco, Brazil. Out of 984 quarter milk (246 cows), 10 (1.0%) were positive for clinical mastitis, 562 (57.1%) for subclinical mastitis and 412 (41.9%) were negative. A total of 81 Staphylococcus spp. isolates were obtained from milk samples from the cows diagnosed with subclinical mastitis. From these, 53 (65.0%) were S. aureus, 16 (20.0%) coagulase-positive staphylococci (CPS) and 12 (15.0%) coagulase-negative staphylococci (CNS). The isolates were further investigated for the presence of toxin genes by multiplex and uniplex PCR. The main gene observed was seg followed by seh, sei and sej. The distribution of these observed genes among the isolates obtained from different areas showed a regional pattern for the SEs. The presence of toxin genes in the strains isolated from bovine milk demonstrates a potential problem for public health.(AU)
O presente estudo foi realizado em 11 rebanhos leiteiros de quatro municípios da área rural do estado de Pernambuco, Brasil. Dos 984 quartos mamários examinados (246 vacas), 10 (1,0%) foram positivos para a mastite clínica, 562 (57,1%) para a mastite subclínica e 412 (41,9%) foram negativos para mastite. Foram isoladas 81 linhagens de Staphylococcus spp. do leite de vacas com mastite subclínica. Destes, 53 (65,0%) foram S. aureus, 16 (20,0%) estafilococos coagulase-positivo (SCP) e 12 (15,0%) estafilococos coagulase-negativo (SCN). O principal gene observado nos estafilococos foi o seg seguido pelo seh, sei e sej. Foi constatada distribuição regional dos genes dos estafilococos isolados dos animais nos municípios estudados. A presença dos genes das toxinas nas linhagens isoladas do leite de vacas representa risco potencial para a Saúde Pública.(AU)
Assuntos
Animais , Bovinos , Staphylococcus/isolamento & purificação , Staphylococcus/genética , Leite , Mastite BovinaRESUMO
O leite e o queijo têm um importante papel nutricional para o homem e quando consumidos sem o devido cuidado higiênico-sanitário, podem causar doenças devido à presença de microrganismos patogênicos, com destaque para Staphylococcus aureus. O envolvimento desta bactéria na epidemiologia das doenças veiculadas por alimentos decorre de sua alta prevalência e do risco de produção de enterotoxinas termoestáveis responsáveis pela intoxicação alimentar. S. aureus também produz outras toxinas de interesse humano como a toxina-1 da síndrome do choque tóxico, responsável pela síndrome do choque tóxico em humanos e as toxinas esfoliativas, causadoras da síndrome da pele escaldada. Alguns grupos vêm aplicando análises moleculares do gene da coagulase para subdividir os S. aureus baseando-se no polimorfismo deste gene. A resistência bacteriana a antibióticos é um sério problema para a Saúde Pública, pois bactérias resistentes podem ser transmitidas ao homem através de alimentos contaminados. Este trabalho teve como objetivos isolar S. aureus obtidos de leite e queijo de coalho da região Agreste de Pernambuco; caracterizar o perfil de sensibilidade antimicrobiana; pesquisar a presença dos genes responsáveis pelas toxinas; investigar a expressão dos genes toxigênicos nos S. aureus e correlacionar a tipagem molecular pelo gene da coagulase com os genes toxigênicos. Os perfis de sensibilidade demonstraram que a maioria dos S. aureus foi sensível a vancomicina, sulfa + trimetoprim e enrofloxacina e alguns isolados demonstraram alto índice de resistência aos demais antibióticos estudados. A análise do gene coa nos 94 isolados de S. aureus permitiu distribuílos em dois coagulotipos: coa1= ~750pb e coa2= ~1000pb sugerindo a disseminação de clones restritos na região Agreste de Pernambuco. Entre os 88 S. aureus positivos pela PCR, foram encontrados os genótipos seg, seh, sei, seg + seh, seg + sei, seg + sej, seh + sei, seg + seh + sei, seg + sei + sej e seg + seh + sei + sej. Estes resultados sugerem a existência de uma variação geográfica na distribuição dos S. aureus portadores dos genes toxigênicos. Destes, 20 isolados foram selecionados para análise pela RT-PCR. Os transcritos obtidos em 12/20 foram seg, seh, sei, seg + seh, seg + sej e seg + sei + sej, coa1 e coa2. Os isolados de S. aureus positivos pela PCR e RT-PCR examinados neste estudo expressaram os genes responsáveis pelas enterotoxinas apresentando potencial para causarem quadros de intoxicação alimentar.