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Orange processing generates peel by-products rich in phenolic compounds, particularly flavanones like hesperidin and narirutin, offering potential health benefits. Utilizing these by-products is of significant interest in supporting Spain's circular bioeconomy. Therefore, the aim of this study was to investigate the fermentation of orange peels by different lactic acid bacteria (LAB) strains and its impact on phenolic composition and antioxidant activity. Three different LAB strains, two Lactiplantibacillus plantarum, and one Levilactobacillus brevis were utilized. The phenolic compounds were measured by HPLC-ESI-TOF-MS, and antioxidant activity was assessed using DPPH and ABTS methods. The growth of the LAB strains varied, showing initial increases followed by gradual declines, with strain-specific patterns observed. Medium acidification occurred during fermentation. A phenolic analysis revealed an 11% increase in phenolic acids in peels fermented by La. plantarum CECT 9567-C4 after 24 h, attributed to glycosylation by LAB enzymes. The flavonoid content exhibited diverse trends, with Le. brevis showing an 8% increase. The antioxidant assays demonstrated strain- and time-dependent variations. Positive correlations were found between antioxidant activity and total phenolic compounds. The results underscore the importance of bacterial selection and fermentation time for tailored phenolic composition and antioxidant activity in orange peel extracts. LAB fermentation, particularly with La. plantarum CECT 9567 and Le. brevis, holds promise for enhancing the recovery of phenolic compounds and augmenting antioxidant activity in orange peels, suggesting potential applications in food and beverage processing.
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The growing global consumption of avocados, associated with contents including bioactive compounds with numerous health-promoting properties, is producing a large amount of agro wastes around the world. Different management approaches are available for the recovery of bioactive compounds from wastes as potential ingredients for use in the production of functional foods and nutraceuticals. Lactic acid fermentation can be used to exploit nutritional potential and add value to agro wastes. In this study, fermentations with lactic acid bacteria were carried out in avocado leaves, and the total phenolic content and the antioxidant activity were determined by DPPH and FRAP assays from hydroalcoholic extracts obtained from fermented avocado leaves. Fifteen new phenolic compounds were identified for the first time in avocado leaves by HPLC-ESI-TOF-MS. L. plantarum CECT 748T and P. pentosaceus CECT 4695T showed the highest antioxidant activity. The sum of phenolic compounds was increased by 71, 62, 55 and 21% in fermentations with P. pentosaceus CECT 4695T, L. brevis CECT 5354, P. acidilactici CECT 5765T and L. plantarum CECT 9567, respectively, while it was reduced in the fermentation with L. plantarum 748T by 21% as demonstrated by HPLC-ESI-TOF-MS. Biotransformations induced by bacterial metabolism modified the phenolic compound profile of avocado leaves in a strain-specific-dependent manner. P. pentosaceus CECT 4695T significantly increased kaempferol, P. pentosaceus 4695T, L. brevis 5354 and L. plantarum 9567 increased rutin, and dihydro-p-coumaric acid was increased by the five selected lactic acid bacteria. Total flavonoids were highly increased after fermentations with the five selected lactic acid bacteria but flavonoid glucosides were decreased by L. plantarum 748T, which was related to its higher antioxidant activity. Our results suggest that lactic acid bacteria led the hydrolysis of compounds by enzymatic activity such as glycosidases or decarboxylase and the release of phenolics bound to the plant cell wall, thus improving their bioavailability.
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A sonotrode ultrasound-assisted extraction of phenolic compounds from olive leaves has been developed using a Box-Behnken design to optimize the effects of solvent composition and ultrasound parameters. The determination of single phenolic compounds was performed by HPLC-MS and the highest recovery in total compounds, oleuropein and hydroxytyrosol was achieved using EtOH/H2O (55:45, v/v), 8 min and 100% of amplitude. The optimal conditions were applied on leaves from seven olive cultivars grown under the same conditions and the results were compared with those found by using a conventional ultrasonic bath, obtaining no statistical differences. Moreover, antioxidant activity by FRAP, DPPH and ABTS in these olive leaf extracts was evaluated and they exhibited a significant correlation with oleuropein and total phenolic content. All cultivars of olive leaf extracts were found to be active against S. aureus and methicillin-resistant S. aureus with minimum bactericidal concentration (MBC) values) that ranged from 5.5 to 22.5 mg mL-1. No extracts showed antimicrobial activity against C. albicans. The percentages of mycelium reduction in B. cinerea ranged from 2.2 and 18.1%. Therefore, sonotrode could be considered as an efficient and fast extraction technique that could be easily scaled-up at industrial level, thus allowing for olive leaves to be revalorized.
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In the field of food preservation, encapsulated Essential Oils (EOs) could be the best non-toxic and eco-friendly tool for food preservative applications substituting the chemicals ones that have several disadvantages for the environment and health. Thirteen commercial EOs from plants, fruits, and vegetables were characterized by GC-MS. The antioxidant activity was measured by DPPH and ABTS techniques. Antimicrobial activity was assessed by agar well-diffusion method and the Minimum Inhibitory Concentration (MIC) by agar dilution method against six bacteria, Candida albicans, and Botrytis cinerea. All the EOs tested have demonstrated antioxidant activity in the range of IC50 0.01-105.32 mg/mL. Between them, cinnamon EOs were the best, followed by oregano and thyme EOs. Fennel EO showed the lowest radical scavenging. MIC values ranged from 0.14 to 9 mg/mL. C. cassia, thyme, and oregano EOs were the most effective against the bacterial species tested, and the yeast C. albicans. On the contrary, citric fruit EOs showed low or no inhibition against most bacterial strains. The percentages of inhibition of mycelia growth of B. cinerea ranged from 3.4 to 98.5%. Thyme, oregano, mint, and fennel EOs showed the highest inhibition.
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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
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Humanos , Infecciones por Coronavirus , Neumonía Viral , Betacoronavirus/patogenicidad , Pandemias , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/terapia , Neumonía Viral/diagnóstico , Neumonía Viral/prevención & control , Neumonía Viral/terapiaRESUMEN
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.
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Genoma Bacteriano/genética , Kéfir/microbiología , Lactobacillus plantarum/genética , Lactobacillus plantarum/aislamiento & purificación , Proteínas Bacterianas/genética , Composición de Base/genética , Secuencia de Bases , Lactobacillus plantarum/clasificación , Lactobacillus plantarum/metabolismo , Probióticos , Análisis de Secuencia de ADNRESUMEN
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.
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Proteínas ADAM/genética , Ciclooxigenasa 1/genética , Enteritis/etiología , Microbioma Gastrointestinal , Mucosa Intestinal/metabolismo , Proteínas de la Membrana/genética , Probióticos , Receptor de Endotelina B/genética , Animales , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Expresión Génica , Mucosa Intestinal/patología , Macrófagos/inmunología , Macrófagos/metabolismo , Obesidad , Fenotipo , Ratas , Ratas ZuckerRESUMEN
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.
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Productos Lácteos Cultivados/microbiología , Lactobacillus plantarum/aislamiento & purificación , Lactobacillus plantarum/fisiología , Probióticos , Yersiniosis/prevención & control , Yersinia enterocolitica , Animales , Citocinas/inmunología , Modelos Animales de Enfermedad , Heces/microbiología , Femenino , Inmunoglobulina A Secretora/inmunología , Inmunomodulación , Interferón gamma/sangre , Interferón gamma/inmunología , Intestinos/inmunología , Intestinos/microbiología , Lactobacillus plantarum/crecimiento & desarrollo , Ratones Endogámicos BALB C , Ganglios Linfáticos Agregados/inmunología , Ganglios Linfáticos Agregados/microbiología , Factor de Necrosis Tumoral alfa/inmunología , Yersiniosis/inmunología , Yersinia enterocolitica/crecimiento & desarrollo , Yersinia enterocolitica/inmunologíaRESUMEN
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.
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Antibiosis , Lactobacillus/fisiología , Probióticos , Animales , Infecciones por Enterobacteriaceae/microbiología , Heces/microbiología , Femenino , Listeria monocytogenes/fisiología , Ratones , Salmonella typhimurium/fisiología , Yersinia enterocolitica/fisiologíaRESUMEN
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.
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Apoptosis/efectos de los fármacos , Medios de Cultivo Condicionados/farmacología , Lactobacillus plantarum , Leucemia Promielocítica Aguda/patología , Caspasa 3/metabolismo , Diferenciación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Células HL-60 , Humanos , Lactobacillus plantarum/crecimiento & desarrollo , Lactobacillus plantarum/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Necrosis/inducido químicamente , Especies Reactivas de Oxígeno/metabolismoRESUMEN
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.
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Calcio/farmacocinética , Fermentación , Limosilactobacillus fermentum/metabolismo , Leche/microbiología , Fósforo/farmacocinética , Probióticos , Zinc/farmacocinética , Animales , Bovinos , Microbiología de Alimentos/métodos , Cabras , Magnesio/farmacocinética , Especificidad de la Especie , Espectrofotometría Atómica/métodos , Rayos UltravioletaRESUMEN
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.
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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.
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Adhesión Bacteriana/efectos de los fármacos , Resinas Compuestas/farmacología , Restauración Dental Permanente/métodos , Streptococcus mutans/efectos de los fármacos , Análisis de Varianza , Compómeros/farmacología , Resinas Compuestas/química , Cementos de Ionómero Vítreo/farmacología , Ensayo de Materiales , Estadísticas no Paramétricas , Propiedades de SuperficieRESUMEN
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.
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Citocinas/biosíntesis , Factores Inmunológicos/farmacología , Cetólidos/farmacología , FN-kappa B/metabolismo , Animales , Apoptosis , Camptotecina/toxicidad , Línea Celular , Proliferación Celular , Células Cultivadas , Concanavalina A/inmunología , Femenino , Genes Reporteros , Lipopolisacáridos/inmunología , Luciferasas/genética , Luciferasas/metabolismo , Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Ratones , Ratones Endogámicos BALB C , Óxido Nítrico/biosíntesisRESUMEN
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.
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Bacterias/aislamiento & purificación , Biodiversidad , Intestinos/microbiología , Lactobacillus/aislamiento & purificación , Animales , Bacterias/genética , Técnicas de Tipificación Bacteriana , Dermatoglifia del ADN , ADN Bacteriano/genética , ADN Ribosómico/genética , Heces/microbiología , Femenino , Lactobacillus/genética , Ratones , Ratones Endogámicos BALB C , Análisis Multivariante , Polimorfismo de Longitud del Fragmento de Restricción , Probióticos/química , ARN Ribosómico 16S/genéticaRESUMEN
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.
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Antibacterianos/farmacología , Cetólidos/farmacología , Macrófagos/patología , Neumonía/patología , Mucosa Respiratoria/patología , Animales , Apoptosis/efectos de los fármacos , Líquido del Lavado Bronquioalveolar , Línea Celular , Células Cultivadas , Quimiocina CXCL2/metabolismo , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Lipopolisacáridos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Ratones Endogámicos BALB C , FN-kappa B/metabolismo , Neumonía/inducido químicamente , Neumonía/metabolismo , Mucosa Respiratoria/efectos de los fármacos , Mucosa Respiratoria/metabolismo , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
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.
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Bacterias Anaerobias/crecimiento & desarrollo , Bacterias Grampositivas Formadoras de Endosporas/crecimiento & desarrollo , Huésped Inmunocomprometido , Intestinos/microbiología , Lactobacillus plantarum/crecimiento & desarrollo , Probióticos/administración & dosificación , Animales , Bacterias Anaerobias/genética , Bacterias Anaerobias/aislamiento & purificación , Dermatoglifia del ADN/métodos , ADN Bacteriano/análisis , Modelos Animales de Enfermedad , Electroforesis en Gel de Poliacrilamida , Femenino , Bacterias Grampositivas Formadoras de Endosporas/genética , Bacterias Grampositivas Formadoras de Endosporas/aislamiento & purificación , Íleon/microbiología , Ratones , Ratones Endogámicos BALB C , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de RestricciónRESUMEN
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.
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Citocinas/sangre , Lactobacillus plantarum , Listeria monocytogenes , Listeriosis/inmunología , Listeriosis/terapia , Probióticos/administración & dosificación , Animales , Interleucina-1beta/sangre , Interleucina-6/sangre , Hígado/inmunología , Hígado/microbiología , Ratones , Ratones Endogámicos BALB C , Modelos Animales , Bazo/inmunología , Bazo/microbiología , Factor de Necrosis Tumoral alfa/sangreRESUMEN
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.