Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Gut Microbes ; 13(1): 1-20, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33615992

RESUMEN

An increasing body of evidence has shown that gut microbiota imbalances are linked to diseases. Currently, the possibility of regulating gut microbiota to reverse these perturbations by developing novel therapeutic and preventive strategies is being extensively investigated. The modulatory effect of vitamins on the gut microbiome and related host health benefits remain largely unclear. We investigated the effects of colon-delivered vitamins A, B2, C, D, and E on the gut microbiota using a human clinical study and batch fermentation experiments, in combination with cell models for the assessment of barrier and immune functions. Vitamins C, B2, and D may modulate the human gut microbiome in terms of metabolic activity and bacterial composition. The most distinct effect was that of vitamin C, which significantly increased microbial alpha diversity and fecal short-chain fatty acids compared to the placebo. The remaining vitamins tested showed similar effects on microbial diversity, composition, and/or metabolic activity in vitro, but in varying degrees. Here, we showed that vitamins may modulate the human gut microbiome. Follow-up studies investigating targeted delivery of vitamins to the colon may help clarify the clinical significance of this novel concept for treating and preventing dysbiotic microbiota-related human diseases. Trial registration: ClinicalTrials.gov, NCT03668964. Registered 13 September 2018 - Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT03668964.


Asunto(s)
Bacterias/crecimiento & desarrollo , Colon/metabolismo , Suplementos Dietéticos , Microbioma Gastrointestinal/fisiología , Vitaminas/administración & dosificación , Ácido Ascórbico/administración & dosificación , Ácido Ascórbico/farmacocinética , Bacterias/clasificación , Bacterias/metabolismo , Células CACO-2 , Colon/microbiología , Citocinas/metabolismo , Método Doble Ciego , Sistemas de Liberación de Medicamentos , Ácidos Grasos Volátiles/metabolismo , Heces/microbiología , Fermentación , Células HT29 , Humanos , Proyectos Piloto , Riboflavina/administración & dosificación , Riboflavina/farmacocinética , Vitamina A/administración & dosificación , Vitamina A/farmacocinética , Vitamina D/administración & dosificación , Vitamina D/farmacocinética , Vitamina E/administración & dosificación , Vitamina E/farmacocinética , Vitaminas/farmacocinética
2.
Lancet Infect Dis ; 21(3): 427-436, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32949500

RESUMEN

BACKGROUND: Urinary tract infections (UTIs) are among the most prevalent microbial diseases and their financial burden on society is substantial. In the context of increasing antibiotic resistance, finding alternative treatments for UTIs is a top priority. We aimed to determine whether intravesical bacteriophage therapy with a commercial bacteriophage cocktail is effective in treating UTI. METHODS: We did a randomised, placebo-controlled, clinical trial, at the Alexander Tsulukidze National Centre of Urology, Tbilisi, Georgia. Men older than 18 years of age, who were scheduled for transurethral resection of the prostate (TURP), with complicated UTI or recurrent uncomplicated UTI but no signs of systemic infection, were allocated by block randomisation in a 1:1:1 ratio to receive intravesical Pyo bacteriophage (Pyophage; 20 mL) or intravesical placebo solution (20 mL) in a double-blind manner twice daily for 7 days, or systemically applied antibiotics (according to sensitivities) as an open-label standard-of-care comparator. Urine culture was taken via urinary catheter at the end of treatment (ie, day 7) or at withdrawal from the trial. The primary outcome was microbiological treatment response after 7 days of treatment, measured by urine culture; secondary outcomes included clinical and safety parameters during the treatment period. Analyses were done in a modified intention-to-treat population of patients having received at least one dose of the allocated treatment regimen. This trial is registered with ClinicalTrials.gov, NCT03140085. FINDINGS: Between June 2, 2017, and Dec 14, 2018, 474 patients were screened for eligibility and 113 (24%) patients were randomly assigned to treatment (37 to Pyophage, 38 to placebo, and 38 to antibiotic treatment). 97 patients (28 Pyophage, 32 placebo, 37 antibiotics) received at least one dose of their allocated treatment and were included in the primary analysis. Treatment success rates did not differ between groups. Normalisation of urine culture was achieved in five (18%) of 28 patients in the Pyophage group compared with nine (28%) of 32 patients in the placebo group (odds ratio [OR] 1·60 [95% CI 0·45-5·71]; p=0·47) and 13 (35%) of 37 patients in the antibiotic group (2·66 [0·79-8·82]; p=0·11). Adverse events occurred in six (21%) of 28 patients in the Pyophage group compared with 13 (41%) of 32 patients in the placebo group (OR 0·36 [95% CI 0·11-1·17]; p=0·089) and 11 (30%) of 37 patients in the antibiotic group (0·66 [0·21-2·07]; p=0·47). INTERPRETATION: Intravesical bacteriophage therapy was non-inferior to standard-of-care antibiotic treatment, but was not superior to placebo bladder irrigation, in terms of efficacy or safety in treating UTIs in patients undergoing TURP. Moreover, the bacteriophage safety profile seems to be favourable. Although bacteriophages are not yet a recognised or approved treatment option for UTIs, this trial provides new insight to optimise the design of further large-scale clinical studies to define the role of bacteriophages in UTI treatment. FUNDING: Swiss Continence Foundation, the Swiss National Science Foundation, and the Swiss Agency for Development and Cooperation. TRANSLATIONS: For the Georgian and German translations of the abstract see Supplementary Materials section.


Asunto(s)
Bacteriófagos/crecimiento & desarrollo , Terapia de Fagos/métodos , Resección Transuretral de la Próstata/efectos adversos , Infecciones Urinarias/terapia , Anciano , Antibacterianos/uso terapéutico , Método Doble Ciego , Georgia , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/etiología
3.
BMC Urol ; 17(1): 90, 2017 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-28950849

RESUMEN

BACKGROUND: Urinary tract infections (UTI) are among the most prevalent microbial diseases and their financial burden on society is substantial. The continuing increase of antibiotic resistance worldwide is alarming. Thus, well-tolerated, highly effective therapeutic alternatives are urgently needed. Although there is evidence indicating that bacteriophage therapy may be effective and safe for treating UTIs, the number of investigated patients is low and there is a lack of randomized controlled trials. METHODS AND DESIGN: This study is the first randomized, placebo-controlled, double-blind trial investigating bacteriophages in UTI treatment. Patients planned for transurethral resection of the prostate are screened for UTIs and enrolled if in urine culture eligible microorganisms ≥104 colony forming units/mL are found. Patients are randomized in a double-blind fashion to the 3 study treatment arms in a 1:1:1 ratio to receive either: a) bacteriophage (i.e. commercially available Pyo bacteriophage) solution, b) placebo solution, or c) antibiotic treatment according to the antibiotic sensitivity pattern. All treatments are intended for 7 days. No antibiotic prophylaxes will be given to the double-blinded treatment arms a) and b). As common practice, the Pyo bacteriophage cocktail is subjected to periodic adaptation cycles during the study. Urinalysis, urine culture, bladder and pain diary, and IPSS questionnaire will be completed prior to and at the end of treatment (i.e. after 7 days) or at withdrawal/drop out from the study. Patients with persistent UTIs will undergo antibiotic treatment according to antibiotic sensitivity pattern. DISCUSSION: Based on the high lytic activity and the potential of resistance optimization by direct adaptation of bacteriophages, and considering the continuing increase of antibiotic resistance worldwide, bacteriophage therapy is a very promising treatment option for UTIs. Thus, our randomized controlled trial investigating bacteriophages for treating UTIs will provide essential insights into this potentially revolutionizing treatment option. TRIAL REGISTRATION: This study has been registered at clinicaltrials.gov ( www.clinicaltrials.gov/ct2/show/NCT03140085 ). April 27, 2017.


Asunto(s)
Bacteriófagos , Terapia de Fagos/métodos , Resección Transuretral de la Próstata/efectos adversos , Infecciones Urinarias/terapia , Bacteriófagos/crecimiento & desarrollo , Método Doble Ciego , Humanos , Masculino , Resultado del Tratamiento , Infecciones Urinarias/diagnóstico , Infecciones Urinarias/etiología
4.
Nutrition ; 26(7-8): 835-41, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19931414

RESUMEN

OBJECTIVE: The aim of this study was to establish the bioavailability of different folates produced by engineered Lactococcus lactis strains using a rodent depletion-repletion bioassay. METHODS: Rats were fed a folate-deficient diet, which produces a reversible subclinical folate deficiency, supplemented with different L. lactis cultures that were added as the only source of folate. Three bacterial strains that overexpressed the folC, folKE, or folC +KE genes were used. These strains produce folates with different poly glutamyl tail lengths. The growth response of the rats and the concentration of folates in different organs and blood samples were monitored. RESULTS: The folate produced by the engineered strains was able to compensate the folate depletion in the diet and showed similar bioavailability compared with commercial folic acid that is normally used for food fortification. Folate concentrations in organ and blood samples increased significantly in animals that received the folate-producing strains compared with those that did not receive bacterial supplementation. Hematologic studies also showed that administration of the L. lactis strains was able to revert a partial megaloblastic anemia caused by folate deficiency. No significant differences were observed in the bioavailability of folates containing different glutamyl tail lengths. CONCLUSION: To our knowledge, this is the first study that demonstrated that folates produced by engineered lactic acid bacteria represent a bioavailable source of this essential vitamin.


Asunto(s)
Suplementos Dietéticos , Deficiencia de Ácido Fólico/terapia , Ácido Fólico/biosíntesis , Genes Bacterianos , Lactococcus lactis/metabolismo , Probióticos/uso terapéutico , Anemia Megaloblástica/terapia , Animales , Disponibilidad Biológica , Ácido Fólico/genética , Deficiencia de Ácido Fólico/metabolismo , Ingeniería Genética/métodos , Lactococcus lactis/genética , Masculino , Ratas , Ratas Wistar
5.
Appl Environ Microbiol ; 70(10): 5769-77, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15466513

RESUMEN

This study describes the genetic analysis of the riboflavin (vitamin B(2)) biosynthetic (rib) operon in the lactic acid bacterium Lactococcus lactis subsp. cremoris strain NZ9000. Functional analysis of the genes of the L. lactis rib operon was performed by using complementation studies, as well as by deletion analysis. In addition, gene-specific genetic engineering was used to examine which genes of the rib operon need to be overexpressed in order to effect riboflavin overproduction. Transcriptional regulation of the L. lactis riboflavin biosynthetic process was investigated by using Northern hybridization and primer extension, as well as the analysis of roseoflavin-induced riboflavin-overproducing L. lactis isolates. The latter analysis revealed the presence of both nucleotide replacements and deletions in the regulatory region of the rib operon. The results presented here are an important step toward the development of fermented foods containing increased levels of riboflavin, produced in situ, thus negating the need for vitamin fortification.


Asunto(s)
Lactococcus lactis/metabolismo , Riboflavina/biosíntesis , Secuencia de Bases , ADN Bacteriano/genética , Farmacorresistencia Bacteriana/genética , Escherichia coli/genética , Fermentación , Alimentos Fortificados , Eliminación de Gen , Expresión Génica , Genes Bacterianos , Prueba de Complementación Genética , Ingeniería Genética , Lactococcus lactis/efectos de los fármacos , Lactococcus lactis/genética , Datos de Secuencia Molecular , Mutación , Operón , Riboflavina/análogos & derivados , Riboflavina/genética , Riboflavina/farmacología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA