RESUMEN
Milk is a complex physiological liquid that simultaneously provides nutrients and bioactive components that facilitate the successful postnatal adaptation of the newborn infant by stimulating cellular growth and digestive maturation, the establishment of symbiotic microflora, and the development of gut-associated lymphoid tissues. The number, the potency, and the importance of bioactive compounds in milk and especially in fermented milk products are probably greater than previously thought. They include certain vitamins, specific proteins, bioactive peptides, oligosaccharides, organic (including fatty) acids. Some of them are normal milk components, others emerge during digestive or fermentation processes. Fermented dairy products and probiotic bacteria decrease the absorption of cholesterol. Whey proteins, medium-chain fatty acids and in particular calcium and other minerals may contribute to the beneficial effect of dairy food on body fat and body mass. There has been growing evidence of the role that dairy proteins play in the regulation of satiety, food intake and obesity-related metabolic disorders. Milk proteins, peptides, probiotic lactic acid bacteria, calcium and other minerals can significantly reduce blood pressure. Milk fat contains a number of components having functional properties. Sphingolipids and their active metabolites may exert antimicrobial effects either directly or upon digestion.
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Productos Lácteos , Fermentación , Salud , Leche Humana , Leche , Animales , Alimentos , Humanos , Recién NacidoRESUMEN
We investigated the occurrence and diversity of yeasts and filamentous fungi in bryndza an artisanal Slovak soft spreadable cheese prepared from raw sheep milk or from a mixture of sheep and cow milk. Samples collected during four months of the summer production period from two locations (northern and southern parts of central Slovakia) contained 10(5)-10(7) (cfu) yeasts and about 10(2) (cfu) of mold per gram of wet weight. Further characterization by conventional taxonomy and sequence comparison of D1/D2 region from 26S rRNA gene revealed Mucor circinelloides v. Tieghem as the predominant filamentous fungus. A novel Geotrichum sp. together with Kluyveromyces (K. lactis/K. marxianus) was identified as the most abundant yeast species. Occasionally other yeasts, such as Candida inconspicua, Candida silvae, Pichia fermentans and Trichosporon domesticum were found. Conventional taxonomy readily identified isolates to the genus level, but DNA sequence comparison was capable of discriminating them at the species level.
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Queso/microbiología , Hongos/clasificación , Hongos/aislamiento & purificación , Filogenia , Levaduras/clasificación , Levaduras/aislamiento & purificación , Animales , Bovinos , Recuento de Colonia Microbiana , Microbiología de Alimentos , Hongos/crecimiento & desarrollo , Humanos , Leche/microbiología , Ovinos , Eslovaquia , Especificidad de la Especie , Levaduras/crecimiento & desarrolloRESUMEN
Three hundred and ten enterococcal isolates (178 Enterococcus faecium, 68 E. durans, 49 E. faecalis, 8 E. italicus, 3 E. gallinarum, 3 E. casseliflavus, and 1 E. hirae) from Slovak Bryndza cheese were evaluated for susceptibility to nine antimicrobial agents (vancomycin, teicoplanin, ampicillin, streptomycin, gentamicin, erythromycin, rifampicin, nitrofurantoin, and ciprofloxacin). All enterococcal isolates from Bryndza cheese were susceptible to ampicillin, streptomycin, gentamicin, vancomycin, and teicoplanin as determined by the disk diffusion method. Vancomycin resistance genes vanA and vanB were not detected. Resistance rates of enterococcal isolates to rifampicin, erythromycin, ciprofloxacin, and nitrofurantoin were 24, 26, 2, and 1 %, respectively. Thirty-six % of E. faecium isolates and 22 % of the E. faecalis isolates were resistant to erythromycin. Resistance to rifampicin was similar in E. faecium (31 %) and E. faecalis (29 %). Both E. faecium and E. faecalis strains showed the same resistance to ciprofloxacin (2 %). E. durans isolates showed low levels of resistance to rifampicin, erythromycin, ciprofloxacin, and nitrofurantoin (1-4 %). Forty-eight (30 %) of the E. faecium isolates, two (3 %) of the E. durans isolates, and six (12 %) of the E. faecalis isolates exhibited multidrug resistance. The highest frequency of resistant enterococci was observed in Bryndza produced in winter season.
Asunto(s)
Antiinfecciosos/farmacología , Queso/microbiología , Enterococcus/efectos de los fármacos , Microbiología de Alimentos , Resistencia a Medicamentos , Enterococcus/clasificación , Enterococcus/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Estaciones del Año , EslovaquiaRESUMEN
AIMS: To identify enterococci isolated from sheep milk cheese--bryndza, and to compare differences in the composition of enterococcal microflora affected by the season, and to evaluate the potential presence of vancomycin resistance and virulence determinants. METHODS AND RESULTS: Bacterial strains were isolated during analysis of bryndza cheese and identified on the genus and species level by phenotypic methods and with commercial biochemical sets. The identification of the species, Enterococcus faecium, Ent. durans and Ent. faecalis, was confirmed by PCR using species-specific primers for ddl genes. PCR was also used for assessment of presence of vanA and vanB genes and virulence determinants gelE, agg and cytolysin genes namely: cylL(L), cylL(S), cylM, cylB and cylA. Among 308 Enterococcus sp. strains, 177 isolates were proved to be Ent. faecium, 59 to be Ent. durans and 41 to be Ent. faecalis. Vancomycin resistance genes vanA and vanB were not detected. Agar plate testing confirmed their absence. Gene gelE, however, was found in 20 Ent. faecalis isolates, but only 13 of them showed gelatinase-positive phenotype. Seven isolates had five cytolysin genes, but none of the isolates exhibited a positive haemolytic phenotype. Four isolates possessed the agg gene. The prevalence of Ent. faecium species was highest in samples from the winter season harvest. CONCLUSIONS: Ent. faecium is the dominant enterococcal species in bryndza cheese and the most prevalent in the winter season product. None of the Enterococcus sp. strains was proved to have vanA or vanB genes and the vancomycin resistance. SIGNIFICANCE AND IMPACT OF THE STUDY: To our knowledge, this is the first report of enterococcal microflora in bryndza cheese and its evaluation for the presence of vanA and vanB genes as well as virulence determinants.
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Queso/microbiología , Enterococcus/clasificación , Enterococcus/patogenicidad , Resistencia a la Vancomicina/genética , Factores de Virulencia/genética , Animales , Proteínas Bacterianas/genética , Ligasas de Carbono-Oxígeno/genética , Enterococcus/efectos de los fármacos , Enterococcus/aislamiento & purificación , Enterococcus faecalis/clasificación , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecalis/aislamiento & purificación , Enterococcus faecalis/patogenicidad , Leche/química , Reacción en Cadena de la Polimerasa , Estaciones del Año , Ovinos , VirulenciaRESUMEN
Febrile neutropenia (FN) remains a potentially life-threatening complication of anticancer chemotherapy. Bacterial translocation via intestinal mucosa is a significant mechanism of FN development. Competitive inhibition of bowel colonization by pathogenic microorganisms by lactic acid bacteria could be a useful prevention of FN. The aim of the study was the prevention of FN by probiotic strain Enterococcus faecium M-74 enriched with selenium in leukemic patients. Fourteen (six males/eight females) patients with myelogenous leukemia treated by induction or consolidation chemotherapy were included in the study. Patients received prophylaxis with E. faecium M-74 during one cycle of chemotherapy. The daily dose was 36 x 10(9) CFU tid. Prophylaxis started between day -2 and day +2 of chemotherapy and continued until the absolute neutrophile count (ANC) was >1,000/microl. All patients experienced febrile neutropenia. During 231 days of severe neutropenia, 30 febrile episodes occurred. No any febrile episode or infection provoked by the strain tested was noticed. Tolerance of therapy was excellent without significant adverse effects. Our results demonstrate the safety of the probiotic strain E. faecium M-74 enriched with selenium in leukemic patients with severe neutropenia. However, its administration was not effective in the prevention of febrile neutropenia, but this does not preclude the protective effect of other probiotic strains.
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Antineoplásicos/efectos adversos , Enterococcus faecium , Fiebre/complicaciones , Neutropenia/prevención & control , Probióticos/uso terapéutico , Adulto , Anciano , Femenino , Fiebre/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Neutropenia/inducido químicamente , Neutropenia/complicaciones , Neutropenia/epidemiología , Eslovaquia/epidemiologíaRESUMEN
OBJECTIVES: To study the effects of long-term probiotic [Enterococcus faecium (EF) M-74 strain] application in humans with respect to adhesion molecules, both soluble forms (sICAM-1, sPECAM-1) and their expression on leukocytes. METHODS: Double-blinded randomized and placebo controlled study lasting for 60 weeks. A single capsule containing either 2x10(9) of bacteria EF M-74 with 50 microg of organically bound selenium (E-group) or placebo (P-group) was given to volunteers. Peripheral blood was analyzed for the expression of particular adhesive molecules. RESULTS AND CONCLUSIONS: We observed significant changes in CAMs expression in terms of a decrease in sICAM-1, CD54 on monocytes and CD11b on lymphocytes after one-year administration of Enterococcus faecium M-74 in humans. Anti-adhesion-aimed therapeutic modalities may provide the future approach to prevention and treatment of cardiovascular diseases. Application of probiotics may be part of such strategies. (Tab. 2, Fig. 6, Ref. 41.)
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Enterococcus faecium , Integrina alfa4/biosíntesis , Molécula 1 de Adhesión Intercelular/biosíntesis , Linfocitos/metabolismo , Monocitos/metabolismo , Probióticos/administración & dosificación , Administración Oral , Anciano , Método Doble Ciego , Femenino , Humanos , Masculino , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/biosíntesis , Probióticos/farmacologíaRESUMEN
OBJECTIVES: To investigate the impact of long-term orally administered probiotic strain Enterococcus faecium (EF) M-74 enriched with selenium on lipid profile (total cholesterol, LDH, HDL, and triglycerides) in humans. BACKGROUND: The discovery that hypercholesterolemia plays a major role in the development of atherosclerosis has led to a number of pharmacological and non-pharmacological (including dietary) approaches resulting in its elimination. Up to now, the question of supposed hypocholesterolemic effect of probiotics has not been definitely established. METHODS: 43 volunteers were randomized into two groups. Participants were given single capsule a day containing 2x10(9) of EF M-74 plus 50 microg of organically bound selenium (E-group) or placebo (P-group). The study was double-blind and lasted 60 weeks. Peripheral blood was analyzed for lipid parameters before intervention, after 6, 12, 23, 44, and 56 weeks of capsule administration, and four weeks following interruption of administration. RESULTS: After 56 weeks of application, decrease in total cholesterol in E-group (17/3 women/men, mean age 75.4+/-1.5 year) was observed (5.94+/-0.29 mmol/l at week 0 vs 5.22+/-0.25 mmol/l after 56 weeks, p<0.001). This reduction was achieved mainly due to a fall in LDL cholesterol (3.85+/-0.27 vs 3.09+/-0.21 mmol/l, p<0.001), as no significant alterations in HDL and triglycerides were noted. In placebo group (14/4, 78.1+/-1.7 year), no statistically important changes were observed after one-year capsule administration. CONCLUSIONS: In our study, the administration of E. faecium M-74 probiotic strain was associated with reduction of serum cholesterol concentration by 12% after 56 weeks. The crescent amount of facts on this issue gives a solid reason to assume that probiotics will find their place as a therapeutic alternative in human medicine. (Tab. 4, Fig. 4, Ref: 36.)
Asunto(s)
Anticolesterolemiantes/administración & dosificación , Colesterol/sangre , Enterococcus faecium , Probióticos/administración & dosificación , Anciano , Método Doble Ciego , Femenino , Humanos , Masculino , Triglicéridos/sangreRESUMEN
Febrile neutropenia (FN) remains a potentially life-threatening complication of anticancer chemotherapy. Bacterial translocation via intestinal mucosa is a significant mechanism of FN development. Competitive inhibition of bowel colonization by pathogenic microorganisms by lactic acid bacteria could be a useful prevention of FN. The aim of the study was the evaluation of dose and safety of probiotic strain Enterococcus faecium M-74 enriched with organic selenium in patients with solid and hematological malignancies. Eleven (9 M/2F) patients were included in the study. In the first phase six patients with germ cell tumors treated by chemotherapy were included. They received prophylaxis by nonpathogenic strain E. faecium M-74 during 2 cycles of chemotherapy. The planned daily dose was 6 x 10(9) bacteria. Regarding the insufficient colonization of the gut, the dose was further increased up to 18 x 10(9) tid. After safety evaluation, five patients were included with relapse of acute leukemia. In patients with germ cell cancer, severe neutropenia G3/4 was noted in 10 of 12 cycles of chemotherapy. The febrile episode was not observed in any of the patients. The gut colonization by enterococci reaches 10(6) CFU/g stool. In 5 patients with acute leukemia during 127 days of severe neutropenia 12 febrile episodes occurred. There was not noted any febrile episode or infection provoked by the tested strain. Tolerance of therapy was excellent without significant undesirable effects. Optimal dose was assessed and safety of probiotic strain was evaluated in neutropenic patients with solid, or hematological malignancies. Based on these results we plan phase II study to evaluate the effectiveness of this strain in FN prophylaxis.
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Antineoplásicos/efectos adversos , Enterococcus faecium/crecimiento & desarrollo , Fiebre/inducido químicamente , Fiebre/prevención & control , Neoplasias de Células Germinales y Embrionarias/tratamiento farmacológico , Neutropenia/inducido químicamente , Neutropenia/prevención & control , Probióticos , Administración Oral , Adulto , Antineoplásicos/uso terapéutico , Femenino , Humanos , Mucosa Intestinal/microbiología , Leucemia/tratamiento farmacológico , Masculino , Persona de Mediana Edad , SelenioRESUMEN
Intraepithelial bacteria were isolated by the gentamicin protection assay (GPA) from biopsy samples obtained at colonoscopy (colon cancer, n = 10 patients; colonic adenoma, n = 20; control group, n = 20; cancer patients without gastrointestinal tract GIT malignancy, n = 10). After a three-month administration of E. faecium M-74 to patients with positive GPA biopsies, 172 biopsy specimens from 60 patients were examined with the GPA. The number of biopsies with intracellular bacteria was significantly higher in adenoma and carcinoma group than in control group (26 vs. 10%; p = 0.004); in cancer patients without GIT malignancy the difference was nonsignificant. E. faecium M-74 was also administered to 5 patients with colonic adenoma; according to a control colonoscopy the number of biopsies with intracellular bacteria was significantly lower after probiotic administration (48 vs. 16%; p = 0.03). A striking prevalence of intraepithelial bacteria was also showed in patients with large bowel adenoma and carcinoma. The administration of probiotic strain M-74 can thus be considered to be an effective and promising method for elimination of pathogenic bacteria in the case of inflammatory bowel disease and colon cancer.
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Neoplasias del Colon/microbiología , Enterobacteriaceae/aislamiento & purificación , Enterococcus faecium , Mucosa Intestinal/microbiología , Probióticos/administración & dosificación , Adenoma/microbiología , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Enterobacteriaceae/crecimiento & desarrollo , Enterococcus faecium/crecimiento & desarrollo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Probióticos/farmacología , Selenio/metabolismoRESUMEN
BACKGROUND: Several reports about usefulness of probiotics, including Enterococcus faecium in the treatment of chronic hepatic encephalopathy in patients with liver cirrhosis have been recently published. The results obtained by the administration of Enterococcus faecium M-74 + selenium will be evaluated and compared with those published by Loguercio et al. for Enterococcus faecium SF 68. METHODS AND RESULTS: Fifteen patients with liver cirrhosis, portal hypertension and chronic hepatic encephalopathy were treated, beside the standard therapy, also with one capsule of probiotic "Enterococcus faecium M-74 + Selenium" per day in three four-week periods, separated by two fortnight pauses. During the treatment, every patient was examined 9-times. The severity of chronic hepatic encephalopathy was evaluated with the aid of the portal systemic encephalopathy index, calculated from 5 parameters (mental stage, asterixis, number connecting test, blood ammonia, EEG). The indexes of initial and final values were compared. The time course of blood ammonia levels and that of results from number connecting test in either study were mutually compared on the basis of interval estimates of quadratic regression function. Significant improvement of the portal systemic encephalopathy index after the treatment was found: it decreased in average by 70% (55 to 85%, interval 95% confidence interval). The mental stage improved and the asterixis disappeared. The blood ammonia levels as well as the results from the number-connecting test after 8-9 weeks significantly approached the normal pattern. EEG findings improved and they were often normalised. Our starting blood ammonia levels (increased by 31% above norm) and results from the connecting test (increased by 60%) were significantly lower accordingly the Loguercio et al. (increased by 243 and 238%, respectively). During the treatment, the values in our study decreased by 25% and 30%, in the compared study by 50% and 70%. CONCLUSIONS: Our results proved the hypothetical favourable effect of probioticum Enterococcus faecium M-74 + Selenium on chronic hepatic encephalopathy. Interestingly, a markedly higher relative therapeutic effect has been achieved in more serious disorder in comparison with the less severe disorders in the present study.
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Enterococcus faecium , Encefalopatía Hepática/terapia , Probióticos/uso terapéutico , Adulto , Anciano , Enfermedad Crónica , Femenino , Encefalopatía Hepática/diagnóstico , Encefalopatía Hepática/etiología , Humanos , Cirrosis Hepática/complicaciones , Masculino , Persona de Mediana Edad , Selenio/uso terapéuticoRESUMEN
Concentrated extracts of MRS (De Man-Rogosa-Sharpe) media in which probiotic bacterium Enterococcus faecium strain M-74 was grown exerted different antimutagenic activity against ofloxacin-, N-methyl, N'-nitro-N-nitrosoguanidine- and sodium 5-nitro-2-furylacrylate-induced mutagenicity in Salmonella typhimurium assay depending on the presence (+Se) or absence of disodium selenite pentahydrate (-Se). The antimutagenicity of MRS(+Se) extract was higher than that of MRS(-Se) extract. Selenium enhanced also the antimutagenic effect of both live and killed cells of E. faecium M-74, respectively. The live bacteria decreased the mutagenicity of selected substances more than killed cells. Synergic activity of selenium with the bacterium was also manifested.
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Enterococcus faecium/fisiología , Mutagénesis/efectos de los fármacos , Mutágenos/toxicidad , Probióticos/farmacología , Salmonella typhimurium/efectos de los fármacos , Selenio/farmacología , Antimutagênicos/farmacología , Sinergismo Farmacológico , Enterococcus faecium/metabolismo , Pruebas de Mutagenicidad , Salmonella typhimurium/genéticaRESUMEN
The aim of the present study was to test the effect of long-term application of diet containing Enterococcus faecium M-74 with organic selenium on tumor induction in transgenic mice carrying mutation in Apc gene. Heterozygosity for the Apc1638N mutation in mice causes development of small intestine and gastric tumors. Feeding of Apc1638N transgenic mice with enriched diet with probiotic components during 8 months have shown a minor therapeutic effect on the clinical manifestations in small intestine in comparison with control group.
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Dieta , Enterococcus faecium , Neoplasias Gastrointestinales/genética , Genes APC , Probióticos , Selenio/uso terapéutico , Adenocarcinoma/genética , Adenocarcinoma/patología , Animales , Secuencia de Bases , Mutación del Sistema de Lectura , Liofilización , Neoplasias Gastrointestinales/patología , Neoplasias Gastrointestinales/terapia , Terapia Genética , Genotipo , Homocigoto , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Reacción en Cadena de la PolimerasaRESUMEN
Almost all nutrients in the diet play a crucial role in maintaining an "optimal" immune response, and both insufficient and excessive intakes can have negative consequences on the immune status and susceptibility to a variety of pathogens. We summarize the evidence for the importance of two micronutrients, selenium and zinc, and describe the mechanisms through which they affect the immune status and other physiological functions. As a constituent of selenoproteins, selenium is needed for the proper functioning of neutrophils, macrophages, NK cells, T lymphocytes and some other immune mechanisms. Elevated selenium intake may be associated with reduced cancer risk and may alleviate other pathological conditions including oxidative stress and inflammation. Selenium appears to be a key nutrient in counteracting the development of virulence and inhibiting HIV progression to AIDS. It is required for sperm motility and may reduce the risk of miscarriage. Selenium deficiency has been linked to adverse mood states and some findings suggest that selenium deficiency may be a risk factor in cardiovascular diseases. Zinc is required as a catalytic, structural and regulatory ion for enzymes, proteins and transcription factors, and is thus a key trace element in many homeostatic mechanisms of the body, including immune responses. Low zinc ion bioavailability results in limited immunoresistance to infection in aging. Physiological supplementation of zinc for 1-2 months restores immune responses, reduces the incidence of infections and prolongs survival. However, in every single individual zinc supplementation of food should be adjusted to the particular zinc status in views of the great variability in habitat conditions, health status and dietary requirements.
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Sistema Inmunológico/efectos de los fármacos , Selenio/farmacología , Zinc/farmacología , Suplementos Dietéticos , Femenino , Humanos , Masculino , Selenio/inmunología , Selenio/metabolismo , Zinc/inmunología , Zinc/metabolismoRESUMEN
The efficacy of combination therapy with methotrexate (MTX) and probiotic bacteria Enterococcus faecium enriched with organic selenium (EFSe) in rats with adjuvant arthritis was determined. Rats with adjuvant arthritis were given MTX (0.3 mg/kg 2-times weekly, orally); lyophilized E. faecium enriched with Se (15 mg/kg, 5 d per week, orally); and a combination of MTX plus EFSe for a period of 50 d from the immunization. Levels of serum albumin, serum nitrite/nitrate concentrations, changes in hind paw swelling, arthrogram score, bone erosions, whole body bone mineral density (BMD) and bone mineral content (BMC) were assayed in the rats as variables of inflammation and destructive arthritis-associated changes. Treatment with MTX and with the combination MTX + EFSe significantly inhibited markers of both inflammation and arthritis. Significant differences in favor of combination therapy with MTX + EFSe as compared to MTX alone were seen in serum albumin concentration, hind paw swelling and arthrogram score. Reductions in radiographic scores were also more pronounced in the combination therapy group. Combination therapy, but not MTX alone, inhibited the reduction of BMD and BMC; treatment with lyophilized EFSe alone had no significant effect on adjuvant arthritis in rats. The potent therapeutic effect of low dosage MTX therapy in combination with lyophilized EFSe on adjuvant arthritis in rats was shown.
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Antirreumáticos/uso terapéutico , Artritis Experimental/terapia , Enterococcus faecium , Metotrexato/uso terapéutico , Probióticos/uso terapéutico , Selenio/uso terapéutico , Animales , Antirreumáticos/administración & dosificación , Artritis Reumatoide/terapia , Densidad Ósea , Quimioterapia Combinada , Pie/patología , Masculino , Metotrexato/administración & dosificación , Nitratos/sangre , Nitritos/sangre , Probióticos/administración & dosificación , Ratas , Ratas Endogámicas Lew , Selenio/administración & dosificación , Resultado del TratamientoRESUMEN
Interorganellar regulatory interactions in the flagellate Euglena gracilis were shown to be more complicated than in green algae and higher plants. Euglena plastids have a much more complex influence on nuclear gene expression than was previously thought. The petJ gene for cytochrome c6 represents a group of nucleus-encoded genes for chloroplast proteins, the expression of which is influenced by the state of plastids at the transcriptional level. Moroever, the regulation of these genes might be light-dependent. In contrast, for nucleus-encoded small subunit of ribulose-bisphosphate carboxylase, chlorophyll a/b binding protein, and porphobilinogen deaminase transcript levels are unchanged in wild-type cells relative to white mutants. In these cases there is no plastid-derived signal operative during transcription. Porphobilinogen deaminase appeared to be regulated even at the post-translational level.
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Euglena gracilis/genética , Complejos de Proteína Captadores de Luz , Luz , Plastidios/metabolismo , Proteínas/genética , Animales , Northern Blotting , Western Blotting , Núcleo Celular/genética , Cloroplastos/química , Cloroplastos/metabolismo , Grupo Citocromo c/genética , Euglena gracilis/metabolismo , Regulación de la Expresión Génica , Hidroximetilbilano Sintasa/análisis , Hidroximetilbilano Sintasa/genética , Hidroximetilbilano Sintasa/metabolismo , Mutación , Proteínas del Complejo del Centro de Reacción Fotosintética/genética , Proteínas/metabolismo , ARN Mensajero/análisis , Ribulosa-Bifosfato Carboxilasa/genética , Transcripción GenéticaRESUMEN
Naturally occurring plant phenolics, p-coumaric acid (PA), caffeic acid (CA), ferulic acid (FA) and gentisic acid (GA) (25-100 nmol/L) had protective effects on acridine orange (AO; 216 mumol/L)- and ofloxacin (3 mumol/L)-induced genotoxicity in Salmonella typhimurium. FA, GA and CA exhibited a significant concentration-dependent protective effect against the genotoxicity of AO and ofloxacin, with the exception of PA, which at all concentrations tested abolished the AO and ofloxacin genotoxicity. UV spectrophotometric measurements showed the interaction of PA, FA, GA and CA with AO but not with ofloxacin; this interaction is obviously responsible for the reduction of AO-induced S. typhimurium mutagenicity. In the case of ofloxacin the antimutagenic effect of PA, FA, GA and CA is assumed to be a result of their ability to scavenge reactive oxygen species (ROS) produced by ofloxacin.
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Naranja de Acridina/toxicidad , Antimutagênicos/farmacología , Gentisatos , Hidroxibenzoatos/farmacología , Mutágenos/toxicidad , Ofloxacino/toxicidad , Salmonella typhimurium/efectos de los fármacos , Ácidos Cafeicos/farmacología , Ácidos Cumáricos/farmacología , Relación Dosis-Respuesta a Droga , Pruebas de Mutagenicidad , Propionatos , Salmonella typhimurium/genéticaRESUMEN
The study was aimed to determine the ability of selected antibiotics and synthetic chemotherapeutic agents to interact with ascorbic acid by means of spectrophotometric measurements and the evaluation of the effect of the presence of ascorbic acid on antimicrobial activity of the substances in which the interaction was detected. Out of 13 chemotherapeutical agents tested, ofloxacine, N-succinimidylofloxacine, fleroxacine, tetracycline, 6-thiatetracycline, and doxycycline reacted with ascorbic acid with the development of the superoxide radical (O2.-). Heatley's method revealed that in the presence of ascorbic acid the antibacterial effect of substances was decreased by 9.6 to 40.7% and 10.1 to 45.1% in Staphylococcus aureus and Escherichia coli, respectively. The kinetics of the process of the survival of cells within 24 hours demonstrated that a combination of ofloxacine as well as tetracycline with ascorbic acid produced a statistically significant increase in log10 of CFU/ml in S. aureus as well as E. coli.
Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Interacciones Farmacológicas , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Espectrofotometría Ultravioleta , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrolloRESUMEN
The possible protective effect of sulphur-free beech lignin polymer on the mutagenicity of ofloxacin in Euglena gracilis was studied. The generation of oxygen species by ofloxacin and their possible interaction with lignin was verified by physico-chemical measurements. The UV absorbance spectra of ofloxacin with and without lignin showed no interaction between these two compounds. The production of superoxide anion radical (O2-) by ofloxacin was significantly reduced in the presence of lignin (AIR = 0.57 +/- 0.03, p < 0.01). Lignin, at concentrations of 125 and 250 micrograms/ml decreased the E. gracilis bleaching activity of ofloxacin to 39.9% and 2.8%, respectively. A lignin concentration of 500 micrograms/ml eliminated the bleaching activity of ofloxacin very efficiently. Our results are consistent with the concept that lignin biopolymer has the capability of reducing genotoxic activity by scavenging reactive oxygen species.
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Antimutagênicos/farmacología , Euglena gracilis/efectos de los fármacos , Lignina/farmacología , Ofloxacino/toxicidad , Animales , Euglena gracilis/fisiología , Depuradores de Radicales Libres , Pruebas de Mutagenicidad , Superóxidos/metabolismoRESUMEN
Lactic acid bacteria in functional foods can transiently colonize the intestine of man and exert beneficial probiotic effects. These were observed in a group of adult subjects administered daily by a lyophilized Enterococcus faecium M-74 in the form of waffles (Dr. Ebi) during nine weeks of a double blind placebo controlled clinical trial. The results showed significant immunostimulatory effect on both phagocytosis by neutrophils and antibody production.
Asunto(s)
Adyuvantes Inmunológicos , Enterococcus faecium , Probióticos/administración & dosificación , Formación de Anticuerpos , Método Doble Ciego , Enterococcus faecium/crecimiento & desarrollo , Humanos , Intestinos/microbiología , Neutrófilos/inmunología , FagocitosisRESUMEN
Lactic acid bacteria in food can transiently colonize the intestine and exert health beneficial (probiotic) effects. These include: 1. Lactose digestion, improvement of diarrheal disorders (including traveller's diarrhea), prophylaxis of intestinal and urogenital infections--as a result of formation or reconstruction of a balanced indigenous microflora. 2. Inhibition of the mutagenicity of the intestinal contents and reduction of the incidence of intestinal tumours. 3. Immunomodulatory effects resulting in the improved host resistance. 4. Depression of the serum cholesterol level. The most of these effects were observed in a group of adult subjects administered daily by a lyophilized Enterococcus faecium M-74 in the form of waffles (Dr. Ebi) during nine weeks of a double blind placebo controlled clinical trial. The bacterium temporarily colonized the host intestine and its secretion in stool persisted for six weeks after the last dose. The mean activities of beta-D-glucuronidase in stools of subjects given waffles containing enterococci were reduced comparing to stools of placebo subjects. After six weeks of daily eating the waffles with enterococci, an increased production of superoxide and other reactive oxygen intermediates by peripheral neutrophils was observed. The increase corresponded in time with an elevated formation of IgG by peripheral blood mononuclear cells after polyclonal activation with mitogenes. Higher activities of myeloperoxidase and elastase in peripheral neutrophils were also ascertained during eating of waffles containing of E. faecium M-74. Hence, intake of E. faecium M-74 in the form of waffles may have an significant immunostimulatory effect on both phagocytosis performed by neutrophils and antibody production. (Tab. 6, Ref. 29.)