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1.
Ars pharm ; 61(2): 63-79, abr.-jun. 2020. tab, ilus, graf
Artigo em Espanhol | IBECS | ID: ibc-188101

RESUMO

INTRODUCCIÓN: En diciembre de 2019, se detectaron los primeros casos de enfermedad respiratoria causada por un coronavirus emergente, al que se denominó SARS-CoV-2, que en los primeros meses de 2020 se ha extendido por todo el mundo con características de pandemia. MÉTODO: Se examinaron las publicaciones más relevantes en relación con los objetivos de la revisión. RESULTADOS: La enfermedad, conocida como COVID-19, cursa con tos, fiebre y dificultad respiratoria. Las formas más graves, que afectan principalmente a personas de edad avanzada y con determinadas comorbilidades, se manifiestan por afectación de la función respiratoria, que requiere ventilación mecánica, y síndrome de respuesta inflamatoria sistémica, que puede conducir a un choque séptico con fallo multiorgánico, y altas tasas de mortalidad. En esta revisión se examina el estado actual de conocimientos sobre las características y origen del SARS-CoV-2, su replicación, y la patogénesis, clínica, diagnóstico, tratamiento y prevención de COVID-19. CONCLUSIONES: Las características del SARS-CoV-2 y la clínica de COVID-19 son bien conocidas. La PCR es la técnica de referencia para el diagnóstico de laboratorio; se dispone de ensayos para detección de antígenos y de anticuerpos, con margen de optimización. Los protocolos de tratamiento incluyen la corrección de la respuesta inflamatoria sistémica y administración de agentes antivirales. Existen vacunas en desarrollo


INTRODUCTION: In December 2019, the first cases of respiratory disease caused by an emerging coronavirus were detected. The causative agento f the outbreak was called SARS-CoV-2, and in the first months of 2020 it spread throughout the world as a pandemic. METHOD: The most relevant publications concerned with the aims of the review were examined. RESULTS: The disease, known as COVID-19. Patients show cough, fever, and respiratory distress. The most severe forms, mainly affecting the elderly and associated with various comorbidities, are manifested by impaired respiratory function, requiring mechanical ventilation, and systemic inflammatory response syndrome, which can lead to septic shock with multi-organ failure and high mortality rates. This review examines the current state of knowledge about the characteristics and origin of SARS-CoV-2, its replication, and the pathogenesis, clinical, diagnosis, treatment, and prevention of COVID-19. CONCLUSIONS: The characteristics of SARS-CoV-2 and the clinical manifestations of COVID-19 are well known. PCR is the reference technique for laboratory diagnosis; assays for the detection of antigens and antibodies are available, with optimization possibilities. Treatment protocols include attenuation of the systemic inflammatory response and administration of antiviral agents. There are vaccines in development


Assuntos
Humanos , Infecções por Coronavirus , Pneumonia Viral , Betacoronavirus/patogenicidade , Pandemias , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Pneumonia Viral/diagnóstico , Pneumonia Viral/prevenção & controle , Pneumonia Viral/terapia
2.
Arch Microbiol ; 201(3): 409-414, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30759265

RESUMO

Lactobacillus plantarum C4 (CECT 9567) was isolated from kefir and has been extensively studied because of its probiotic properties. Here we report the genome sequence of this strain. The genome consists of 3,221,350 bp, and contains 3058 CDSs with an average G + C content of 44.5%. The genome harbors genes encoding the AraC-family transcription regulator, the penicillin-binding protein Pbp2A, and the Na+/H+ antiporter NapA3, which have important roles in the survival of lactobacilli in the gastrointestinal tract. Also, the genome encodes the catalase KatE, NADH peroxidase and glutathione peroxidase, which enable anaerobic respiration, and a nitrate reductase complex, which enable anaerobic respiration. Additionally, genes encoding plantaricins and sactipeptides, and genes involved in the use of fructooligosaccharides and in the production of butyric acid were also identified. BLASTn analysis revealed that 91.4% of CDSs in C4 genome aligned with those of the reference strain L. plantarum WCFS1, with a mean identity of 98.96%. The genome information of L. plantarum C4 provides the basis for understanding the probiotic properties of C4 and to consider its use as a potential component of functional foods.


Assuntos
Genoma Bacteriano/genética , Kefir/microbiologia , Lactobacillus plantarum/genética , Lactobacillus plantarum/isolamento & purificação , Proteínas de Bactérias/genética , Composição de Bases/genética , Sequência de Bases , Lactobacillus plantarum/classificação , Lactobacillus plantarum/metabolismo , Probióticos , Análise de Sequência de DNA
3.
Sci Rep ; 7(1): 1939, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28512356

RESUMO

We have previously reported that administration of Lactobacillus paracasei CNCM I-4034, Bifidobacterium breve CNCM I-4035 and Lactobacillus rhamnosus CNCM I-4036 to obese Zucker-Lepr fa/fa rats attenuates liver steatosis and exerts anti-inflammatory effects. The goal of the present work was to investigate the modulation of gene expression in intestinal mucosa samples of obese Zucker-Lepr fa/fa rats fed the probiotic strains using a DNA microarray and postgenomic techniques. We also measured secretory IgA content in the gut and lipopolysaccharide (LPS)-binding protein (LBP) in serum. Expression of three genes (Adamdec1, Ednrb and Ptgs1/Cox1) was up-regulated in the intestinal mucosa of the obese rats compared with that in the rats when they were still lean. Probiotic administration down-regulated expression of Adamdec1 and Ednrb at the mRNA and protein levels and that of Ptgs1/Cox1 at the mRNA level, and this effect was in part mediated by a decrease in both macrophage and dendritic cell populations. Probiotic treatment also increased secretory IgA content and diminished the LBP concentration. Based on results reported in this work and else where, we propose a possible mechanism of action for these bacterial strains.


Assuntos
Proteínas ADAM/genética , Ciclo-Oxigenase 1/genética , Enterite/etiologia , Microbioma Gastrointestinal , Mucosa Intestinal/metabolismo , Proteínas de Membrana/genética , Probióticos , Receptor de Endotelina B/genética , Animais , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Expressão Gênica , Mucosa Intestinal/patologia , Macrófagos/imunologia , Macrófagos/metabolismo , Obesidade , Fenótipo , Ratos , Ratos Zucker
4.
Res Microbiol ; 166(8): 626-32, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26272025

RESUMO

Lactobacillus plantarum C4, previously isolated from kefir and characterized as a potential probiotic strain, was tested for its protective and immunomodulatory capacity in a murine model of yersiniosis. The inoculation of BALB/c mice with a low pathogenicity serotype O9 strain of Yersinia enterocolitica results in a prolonged intestinal infection with colonization of Peyer's patches. Pretreatment with C4 was without effect on fecal excretion of yersiniae, but shortened the colonization of Peyer's patches. This protective effect was associated with pro-inflammatory status in the intestinal mucosa (TNF-α production in infected mice was increased by C4) and an increase in total IgA secretion. At a systemic level, C4 did not promote a pro-inflammatory response, although production of the immunoregulatory cytokine IFN-γ was enhanced. These findings suggest that L. plantarum C4 can increase resistance to intestinal infections through its immunomodulatory activity.


Assuntos
Produtos Fermentados do Leite/microbiologia , Lactobacillus plantarum/isolamento & purificação , Lactobacillus plantarum/fisiologia , Probióticos , Yersiniose/prevenção & controle , Yersinia enterocolitica , Animais , Citocinas/imunologia , Modelos Animais de Doenças , Fezes/microbiologia , Feminino , Imunoglobulina A Secretora/imunologia , Imunomodulação , Interferon gama/sangue , Interferon gama/imunologia , Intestinos/imunologia , Intestinos/microbiologia , Lactobacillus plantarum/crescimento & desenvolvimento , Camundongos Endogâmicos BALB C , Nódulos Linfáticos Agregados/imunologia , Nódulos Linfáticos Agregados/microbiologia , Fator de Necrose Tumoral alfa/imunologia , Yersiniose/imunologia , Yersinia enterocolitica/crescimento & desenvolvimento , Yersinia enterocolitica/imunologia
5.
Res Microbiol ; 165(1): 14-20, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24140789

RESUMO

Increased resistance to infection is one of the beneficial effects attributed to probiotic microorganisms. This effect may be due to several mechanisms: production of inhibitory substances, blocking of adhesion sites on the intestinal surface, competition for nutrients and stimulation of mucosal and systemic immunity. The present study aimed to investigate the correlation between in vitro and in vivo antimicrobial activity of probiotic lactobacilli. The agar spot test was used to show that twenty Lactobacillus strains were able to inhibit the enteropathogenic bacterium Yersinia enterocolitica. This inhibition was mainly attributable to a decrease in pH resulting from dextrose fermentation by lactobacilli. The inhibition of Y. enterocolitica, Salmonella enterica serovar Typhimurium and Listeria monocytogenes by two probiotic strains, Lactobacillus casei C1 and Lactobacillus plantarum C4, was also associated with the pH decrease. However, both strains lacked protective effects in mouse experimental infection models, with the exception of long-lasting pre-treatment with L. plantarum C4, which exerted a partial protective effect against S. Typhimurium that was attributable to an immunostimulatory mechanism. Our results show that in vitro antibiosis tests do not provide useful information on the probiotic potential of Lactobacillus strains.


Assuntos
Antibiose , Lactobacillus/fisiologia , Probióticos , Animais , Infecções por Enterobacteriaceae/microbiologia , Fezes/microbiologia , Feminino , Listeria monocytogenes/fisiologia , Camundongos , Salmonella typhimurium/fisiologia , Yersinia enterocolitica/fisiologia
6.
Endocr Metab Immune Disord Drug Targets ; 13(2): 195-203, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23701216

RESUMO

AIMS: Lactic acid bacteria (LAB) are known to have antitumoral properties, although the intrinsic mechanisms responsible for the execution of this activity are poorly understood. Here, we investigated the ability of concentrated supernatants from Lactobacillus plantarum to promote cell death in a human promyelocytic cell line. METHODS AND RESULTS: We aim to test the hypothesis that concentrated supernatants from Lact. plantarum at 5, 50 or 100 µg/ml for 24 h exert cytotoxic effects on HL-60 cells. Accumulation of reactive oxygen species (ROS) was diminished and nuclear staining with Hoechst 33342 and propidium iodide (PI) determined a necrotic induction in a concentrationdependent sequence. Concentrated supernatants did not modify or reduced the activity of caspase-3. The assessment of phosphatidylserine externalization by annexin V/PI double staining led to a necrotic state, but the treatment did not produce a dissipation of mitochondrial membrane potential (ΔΨm), whereas cell cycle analysis revealed that concentrated supernatants failed to significantly enhance the population of HL-60 cells in the hypodiploid (sub-G1) fraction. CONCLUSIONS: Concentrated supernatants from Lact. plantarum are capable of inducing necrosis rather than apoptosis at high doses in a promyelocytic cell line. SIGNIFICANCE AND IMPACT OF THE STUDY: Here, we demonstrate the cytotoxic properties of concentrated supernatants from Lact. plantarum on a tumor cell line, and then, to open the possibility to analyze the chemical composition to elucidate the bioactive molecules.


Assuntos
Apoptose/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Lactobacillus plantarum , Leucemia Promielocítica Aguda/patologia , Caspase 3/metabolismo , Diferenciação Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HL-60 , Humanos , Lactobacillus plantarum/crescimento & desenvolvimento , Lactobacillus plantarum/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Necrose/induzido quimicamente , Espécies Reativas de Oxigênio/metabolismo
7.
Biol Trace Elem Res ; 151(2): 307-14, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23179347

RESUMO

We determined calcium, magnesium, phosphorus and zinc levels in a total of 27 samples of commercial goat- and cow-milk fermented products and 9 samples of a goat-milk fermented product with addition of a probiotic bacterial strain, Lactobacillus fermentum D3, manufactured experimentally by our research group. Atomic absorption spectroscopy with flame atomization and UV/VIS spectrophotometry were used as analytic techniques. The results of an in vitro digestion process showed that the bioavailability of calcium, phosphorus, and zinc was significantly higher in our fermented milk containing the probiotic bacterial strain than it was in commercial goat-milk fermented products. Furthermore, our product showed a significantly higher bioavailability of calcium and zinc compared to goat- and cow-milk fermented products made with other microorganisms. We conclude that, in in vitro assays, strain D3 seems to increase the bioavailability of these minerals and that this new product may constitute a better source of bioavailable minerals compared to other products already on the market.


Assuntos
Cálcio/farmacocinética , Fermentação , Lactobacillus fermentum/metabolismo , Leite/microbiologia , Fósforo/farmacocinética , Probióticos , Zinco/farmacocinética , Animais , Bovinos , Microbiologia de Alimentos/métodos , Cabras , Magnésio/farmacocinética , Especificidade da Espécie , Espectrofotometria Atômica/métodos , Raios Ultravioleta
8.
Indian J Virol ; 22(2): 84-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23637508

RESUMO

The role of Human bocavirus (HBoV) in human infectious disease is unclear due to the frequent detection of this virus in association with other respiratory viruses with a recognized pathogenic role in acute respiratory infection. We have analyzed the impact of HBoV in outpatients and in patients requiring hospitalisation or emergency attention for acute respiratory infections. Respiratory viruses were investigated by real-time PCR, direct antigen detection and/or viral culture by shell-vial assay. Nasopharyngeal aspirates, BAL and/or sputum samples from patients attended at a reference hospital, and nasal/throat swabs from outpatients were used. Respiratory viruses were detected in 660 samples (47%). HBoV detection rate was 12.6%, only preceded by respiratory syncytial virus (25%). Co-detections were observed in 12.9% of samples, and HBoV was present in 81% of them. Similar detection rates of HBoV were obtained in individuals with positive and negative results for other respiratory viruses (12.5% and 12.7%, respectively). The crossing point value was taken as a measure of HBoV viral load. Higher HBoV loads were observed in children, and in patients from the hospital. HBoV viral load was not associated with symptoms of upper respiratory tract infection or lower respiratory tract disease. Although HBoV is frequently detected in respiratory specimens, there is a poor association between HBoV-positive specimens and clinical parameters. A clinical impact of HBoV in respiratory infection probably occurs in few cases.

9.
Am J Dent ; 23(5): 275-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21207795

RESUMO

PURPOSE: To investigate the surface roughness and the initial adhesion of Streptococcus mutans on seven dental resin-based restorative materials. METHODS: Five cylinder specimens, with 5 mm diameter and 3 mm height, of three resin composites (Z100, Prodigy and Tetric), three polyacid modified composite resins (Compoglass, Compoglass F and Dyract AP) and a resin modified glass ionomer (Vitremer) were made. Materials were handled following manufacturer's instructions. The materials were polished up to 1200 grit SiC abrasive paper under running water in an automatic polisher. Surface roughness measurements were carried out by a profilometer. Five diametrical measurements were made and Ra was calculated in microm. The bacterial initial cell adhesion assay was performed with S. mutans ATCC 25175. The initial adhesion of Streptococcus mutans on the materials tested was observed by SEM. ANOVA and Student-Newman-Keuls multiple comparisons were used. RESULTS: The statistical analyses showed no significant differences in initial cell adhesion among tested materials, even when the resin-modified glass inonomer showed a rougher surface than the rest of the materials.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Resinas Compostas/farmacologia , Restauração Dentária Permanente/métodos , Streptococcus mutans/efeitos dos fármacos , Análise de Variância , Compômeros/farmacologia , Resinas Compostas/química , Cimentos de Ionômeros de Vidro/farmacologia , Teste de Materiais , Estatísticas não Paramétricas , Propriedades de Superfície
10.
FEMS Immunol Med Microbiol ; 53(3): 343-50, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18557935

RESUMO

Telithromycin is a ketolide antibiotic with anti-inflammatory properties. To investigate the mechanisms of these effects, we examined the in vitro immunomodulatory activity of telithromycin on murine splenocytes and the murine macrophage cell line RAW 264.7. Spleen cells from BALB/c-untreated mice and RAW 264.7 macrophages were cultured in the presence of telithromycin. Proliferation and apoptosis (colorimetric assay), and cytokine production (enzyme immunoassay) of spleen cells in response to lipopolysaccharide and concanavalin A (Con A), and nitric oxide (NO) (colorimetric assay) and cytokine production by lipopolysaccharide-stimulated RAW 264.7 cells were determined. Telithromycin moderately enhanced lymphocyte proliferation in response to lipopolysaccharide and Con A, and enhanced apoptosis induced by camptothecin in mitogen-stimulated splenocytes. Con A-induced IFN-gamma production was suppressed and lipopolysaccharide-induced IL-10 production was increased in spleen cell cultures with telithromycin. Lipopolysaccharide-induced secretion of NO and tumor necrosis factor-alpha (TNF-alpha) was suppressed by telithromycin in RAW 264.7 cultures. Lipopolysaccharide-induced activation of NF-kappaB transcription factor and TNF-alpha promoter in RAW 264.7 macrophages transitorily transfected with luciferase reporter constructs was also inhibited by the ketolide. The suppressive effect of telithromycin on NF-kappaB activation was confirmed by Western blot and enzyme immunoassay. These results suggest that telithromycin exerts anti-inflammatory activity mediated by the inhibition of activation of NF-kappaB.


Assuntos
Citocinas/biossíntese , Fatores Imunológicos/farmacologia , Cetolídeos/farmacologia , NF-kappa B/metabolismo , Animais , Apoptose , Camptotecina/toxicidade , Linhagem Celular , Proliferação de Células , Células Cultivadas , Concanavalina A/imunologia , Feminino , Genes Reporter , Lipopolissacarídeos/imunologia , Luciferases/genética , Luciferases/metabolismo , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/biossíntese
11.
Chest ; 134(1): 20-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18403658

RESUMO

BACKGROUND: The ketolide antibiotic telithromycin (TEL) exerts immunomodulatory and antiinflammatory effects in vitro and in a mouse model of septic shock. We studied the antiinflammatory activity of TEL in in vitro and in vivo models of airway inflammation induced by lipopolysaccharide (LPS). METHODS: We measured the effects of TEL on the response of RAW 264.7 macrophages to LPS and of murine lung epithelial (MLE)-12 cells to supernatants of LPS-stimulated RAW 264.7 macrophages. Macrophage inflammatory protein (MIP)-2 and tumor necrosis factor (TNF)-alpha production, nuclear factor (NF)-kappaB activation, and apoptosis were determined. Acute airway inflammation was induced in untreated and TEL-treated BALB/c mice by nebulization with LPS. Total number of leukocytes, macrophages, and neutrophils, the protein concentration, and nitrite and cytokine levels were determined in the BAL fluid. RESULTS: TEL inhibited in a dose-dependent manner the production of MIP-2 and TNF-alpha by LPS-stimulated RAW 264.7 macrophages, and the production of MIP-2 by MLE-12 epithelial cells to supernatants of LPS-stimulated RAW 264.7 macrophages. NF-kappaB activation was inhibited and apoptosis was increased in both cell lines by TEL. The LPS-induced influx of neutrophils in BAL fluid was decreased by TEL pretreatment. TEL also reduced protein, nitrite, MIP-2, and TNF-alpha levels in the BAL fluid of LPS-nebulized animals. CONCLUSIONS: We have provided evidence that TEL exerts potent antiinflammatory effects in LPS-induced airways injury. We propose that TEL acts in the early phase of inflammation by reducing the release of inflammatory mediators through NF-kappaB inhibition, and in the later phase through enhancement of inflammatory cell apoptosis.


Assuntos
Antibacterianos/farmacologia , Cetolídeos/farmacologia , Macrófagos/patologia , Pneumonia/patologia , Mucosa Respiratória/patologia , Animais , Apoptose/efeitos dos fármacos , Líquido da Lavagem Broncoalveolar , Linhagem Celular , Células Cultivadas , Quimiocina CXCL2/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/metabolismo , Pneumonia/induzido quimicamente , Pneumonia/metabolismo , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
12.
Res Microbiol ; 159(4): 237-43, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18439805

RESUMO

Lactobacilli are normal inhabitants of the gastrointestinal tract (GIT) of many mammalian hosts. Their administration as probiotics in functional foods is currently a frequent practice, mainly because of their benefits to host health. It is therefore of interest to study the impact of administration of exogenous strains of Lactobacillus normally used as probiotics upon endogenous microbial populations. For this purpose, fecal and intestinal tissue samples were analyzed in a mouse model fed with a mixture of Lactobacillus plantarum and Lactobacillus casei isolated from commercially available dairy products. The murine intestinal microbiota was studied by means of cultivation-independent 16S rRNA gene-targeted techniques, namely denaturing gradient gel electrophoresis (DGGE), terminal restriction fragment length polymorphism (T-RFLP) and sequence analysis of clone libraries. Multivariate statistical analysis was used to integrate datasets obtained from the different techniques applied. Whereas no differences were detected in the composition of the overall fecal bacterial community, changes were observed for intestinal tissue samples. Moreover, an increase in the diversity of gut lactobacilli was observed in fecal as well as intestinal tissue samples when mice received the mixture of L. casei and L. plantarum.


Assuntos
Bactérias/isolamento & purificação , Biodiversidade , Intestinos/microbiologia , Lactobacillus/isolamento & purificação , Animais , Bactérias/genética , Técnicas de Tipagem Bacteriana , Impressões Digitais de DNA , DNA Bacteriano/genética , DNA Ribossômico/genética , Fezes/microbiologia , Feminino , Lactobacillus/genética , Camundongos , Camundongos Endogâmicos BALB C , Análise Multivariada , Polimorfismo de Fragmento de Restrição , Probióticos/química , RNA Ribossômico 16S/genética
13.
Br J Nutr ; 99(4): 819-25, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17894920

RESUMO

Lactic acid bacteria have traditionally been thought to have immunomodulating effects. To verify this property, Lactobacillus plantarum was orally administered to mice (5 x 107 colony forming units (c.f.u.)), prior to infection with Listeria monocytogenes in order to evaluate the host resistance against an infectious micro-organism and to better define the influence of L. plantarum on such responses. Balb/c mice were treated daily with L. plantarum or received PBS (sham-treated mice as controls) for 4 weeks. Subsequently, mice were intravenously infected with a clinical isolate of L. monocytogenes. Our study revealed that the administration of L. plantarum did not significantly increase the survival (P = 0.13) of mice (fifteen in each group) after L. monocytogenes infection (106 c.f.u./ml), whereas a sub-lethal dose of L. monocytogenes (105 c.f.u./ml) was eliminated from liver and spleen 5 d after the challenge in both L. plantarum- and sham-treated mice (n 5). Nevertheless, the levels of IL-1beta and IL-6 from sera of orally administered L. plantarum were drastically reduced at 0, 4 (P < 0.01) and 6 d after L. monocytogenes infection, whereas TNF-alpha production was unaltered. In conclusion, administration of L. plantarum reduced pro-inflammatory IL production after challenge with L. monocytogenes, although it did not significantly impact the survival of mice. We speculate that L. plantarum could exert anti-inflammatory effects, which may represent an important model to reduce inflammatory disorders. Therefore, further studies in human subjects should determine the role of L. plantarum as an immunomodulatory micro-organism and its relationship in the host protection to pathogens.


Assuntos
Citocinas/sangue , Lactobacillus plantarum , Listeria monocytogenes , Listeriose/imunologia , Listeriose/terapia , Probióticos/administração & dosagem , Animais , Interleucina-1beta/sangue , Interleucina-6/sangue , Fígado/imunologia , Fígado/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Modelos Animais , Baço/imunologia , Baço/microbiologia , Fator de Necrose Tumoral alfa/sangue
14.
FEMS Microbiol Ecol ; 63(1): 65-72, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18081591

RESUMO

Segmented filamentous bacteria (SFB) are present in the gastrointestinal tract of mice from weaning until the maturation of the immune system. Probiotic bacteria also have an effect on host immunity. To study the relationships established between these bacteria, samples from a mouse model fed with Lactobacillus plantarum under different immunological conditions were analysed. SFB populations were measured by a newly designed group-specific quantitative PCR assay. The results confirmed the presence of the probiotic in the intestine and an expansion of SFB in the ileum of immunocompromised mice, which was abolished upon administration of L. plantarum, an effect not described to date.


Assuntos
Bactérias Anaeróbias/crescimento & desenvolvimento , Bactérias Gram-Positivas Formadoras de Endosporo/crescimento & desenvolvimento , Hospedeiro Imunocomprometido , Intestinos/microbiologia , Lactobacillus plantarum/crescimento & desenvolvimento , Probióticos/administração & dosagem , Animais , Bactérias Anaeróbias/genética , Bactérias Anaeróbias/isolamento & purificação , Impressões Digitais de DNA/métodos , DNA Bacteriano/análise , Modelos Animais de Doenças , Eletroforese em Gel de Poliacrilamida , Feminino , Bactérias Gram-Positivas Formadoras de Endosporo/genética , Bactérias Gram-Positivas Formadoras de Endosporo/isolamento & purificação , Íleo/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
15.
J Clin Microbiol ; 45(9): 3109-10, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17652478

RESUMO

Influenza surveillance networks must detect early the viruses that will cause the forthcoming annual epidemics and isolate the strains for further characterization. We obtained the highest sensitivity (95.4%) with a diagnostic tool that combined a shell-vial assay and reverse transcription-PCR on cell culture supernatants at 48 h, and indeed, recovered the strain.


Assuntos
Influenza Humana/virologia , Técnicas de Diagnóstico Molecular/métodos , Orthomyxoviridae/isolamento & purificação , Virologia/métodos , Cultura de Vírus/métodos , Humanos , Orthomyxoviridae/genética , Orthomyxoviridae/crescimento & desenvolvimento , Sensibilidade e Especificidade , Vigilância de Evento Sentinela
17.
J Microbiol Methods ; 66(3): 572-5, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16554099

RESUMO

The quantification of exogenous lactobacilli in faecal samples is frequently required for the evaluation of the intestinal colonization by probiotic bacteria. In this study, a selective and differential medium, designated LPSM, was developed for the culture of exogenous Lactobacillus plantarum. In quantitative assays, LPSM showed a sensitivity similar to those of enriched and Lactobacillus-adapted media. The presence of ciprofloxacin made LPSM inhibitory to most intestinal bacteria, including endogenous acid lactic bacteria, whereas exogenous L. plantarum strains grew producing a yellow color caused by acid production from sorbitol in the presence of bromocresol purple. The results showed that LPSM is suitable for detection and enumeration of L. plantarum in faecal samples.


Assuntos
Técnicas Bacteriológicas/métodos , Meios de Cultura , Fezes/microbiologia , Lactobacillus plantarum/crescimento & desenvolvimento , Animais , Ciprofloxacino/farmacologia , Contagem de Colônia Microbiana , Resistência Microbiana a Medicamentos , Feminino , Lactobacillus plantarum/isolamento & purificação , Lactobacillus plantarum/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Sensibilidade e Especificidade , Sorbitol/metabolismo
18.
Int J Antimicrob Agents ; 25(3): 252-5, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15737521

RESUMO

To test the role of bacterial fractions released from intestinal flora during immunomodulation by antimicrobial agents, BALB/c mice were treated with the non-absorbable antibiotics polymyxin B or teicoplanin by the intragastric route. The composition of faecal microbiota and the capacity of spleen cells to proliferate in response to B-cell and T-cell mitogens were assessed at several times during the treatment. Both antibiotics lowered the count of some bacteria of the intestinal flora and induced significant modifications in spleen cell ability to proliferate in response to mitogens. Thus, the active fractions released from intestinal bacteria during antibiotic treatments may be able to induce immunomodulating effects.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/imunologia , Trato Gastrointestinal/microbiologia , Ativação Linfocitária , Baço/imunologia , Animais , Antibacterianos/farmacocinética , Contagem de Colônia Microbiana , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Animais , Polimixina B/administração & dosagem , Polimixina B/imunologia , Polimixina B/farmacocinética , Baço/citologia , Teicoplanina/administração & dosagem , Teicoplanina/imunologia , Teicoplanina/farmacocinética
19.
Immunol Cell Biol ; 82(4): 370-6, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15283846

RESUMO

The direct examination of the effects that fish oil diets (composed of long-chain n-3 polyunsaturated fatty acids) exert on immune system function indicates a reduction of host natural resistance to infectious diseases mainly because of a suppression of immune function generated by the fatty acids contained in this diet. Here, we evaluated the concentration of IL-12, IL-4, prostaglandin E2 and leukotriene B4 in the serum from BALB/c mice receiving four different diets. Each group was fed a diet that differed only in the source of fat: a low-fat diet (2.5% by weight), an olive oil diet (20% by weight), a fish oil diet (20% by weight) or a hydrogenated coconut oil diet (20% by weight). Mice were fed for 4 weeks and then infected with the intracellular pathogen Listeria monocytogenes. An initial reduction in the Th1-type response as a result of a decrease in IL-12p70 secretion, an inefficient action of IL-4 (Th2-type response) and no modification of pro-inflammatory lipid-mediator production could be, at least in part, the key events responsible for the inadequate elimination of L. monocytogenes from the spleens of mice fed a fish oil diet. Furthermore, our results suggest that the type of dietary lipids may affect the circulating concentration of IL-12p70 and IL-4, leading to a modulation in the protective cellular immune response to L. monocytogenes infection.


Assuntos
Gorduras na Dieta/farmacologia , Óleos de Peixe/farmacologia , Listeriose/imunologia , Óleos Vegetais/farmacologia , Animais , Peso Corporal , Óleo de Coco , Gorduras na Dieta/administração & dosagem , Dinoprostona/sangue , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Ômega-3/farmacologia , Óleos de Peixe/administração & dosagem , Interleucina-12/biossíntese , Interleucina-4/biossíntese , Leucotrieno B4/sangue , Camundongos , Azeite de Oliva , Tamanho do Órgão , Óleos Vegetais/administração & dosagem , Subunidades Proteicas/biossíntese , Baço/química , Baço/parasitologia
20.
Curr Microbiol ; 48(5): 373-8, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15060735

RESUMO

The potential action of certain fatty acids has been studied since the early 1970s. Numerous effects on immune system functions have been related to dietary lipid administration; therefore, several of them have been applied in the treatment of inflammatory disorders. Nevertheless, n-3 polyunsaturated fatty acids may affect host resistance to infectious diseases. In addition, several studies have demonstrated that certain fatty acids are involved in apoptosis induction. Here, we have examined the action of different dietary lipids on the promotion of apoptosis in thymocytes from mice fed with dietary lipids and infected with Listeria monocytogenes. Thus, L. monocytogenes promoted an important cytotoxic effect in all of the groups, but it did not increase the percentage of DNA fragmentation. Similarly, an important increase of caspase-3 activity was demonstrated in OO and FO groups, but infection with L. monocytogenes exerted an inhibitory effect. Finally, L. monocytogenes did not modify proteasome activity among groups fed with dietary lipids. On the basis of this preliminary study, we can state that the infection of thymocytes from mice fed with dietary lipids does not promote a synergistic effect in the induction of apoptosis. Hence, these results may partially serve to elucidate the immune mechanisms involved in cells from mice fed with dietary lipids in an infectious process.


Assuntos
Apoptose , Gorduras Insaturadas na Dieta/administração & dosagem , Listeria monocytogenes/patogenicidade , Linfócitos T/microbiologia , Linfócitos T/fisiologia , Animais , Caspase 3 , Caspases/metabolismo , Técnicas de Cultura de Células , Óleo de Coco , Cisteína Endopeptidases/metabolismo , Fragmentação do DNA , Óleos de Peixe/administração & dosagem , L-Lactato Desidrogenase/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Complexos Multienzimáticos/metabolismo , Azeite de Oliva , Óleos Vegetais/administração & dosagem , Óleos Vegetais/química , Complexo de Endopeptidases do Proteassoma , Distribuição Aleatória , Timo
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