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3.
Nature ; 618(7967): 981-985, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37225998

RESUMEN

Soils store more carbon than other terrestrial ecosystems1,2. How soil organic carbon (SOC) forms and persists remains uncertain1,3, which makes it challenging to understand how it will respond to climatic change3,4. It has been suggested that soil microorganisms play an important role in SOC formation, preservation and loss5-7. Although microorganisms affect the accumulation and loss of soil organic matter through many pathways4,6,8-11, microbial carbon use efficiency (CUE) is an integrative metric that can capture the balance of these processes12,13. Although CUE has the potential to act as a predictor of variation in SOC storage, the role of CUE in SOC persistence remains unresolved7,14,15. Here we examine the relationship between CUE and the preservation of SOC, and interactions with climate, vegetation and edaphic properties, using a combination of global-scale datasets, a microbial-process explicit model, data assimilation, deep learning and meta-analysis. We find that CUE is at least four times as important as other evaluated factors, such as carbon input, decomposition or vertical transport, in determining SOC storage and its spatial variation across the globe. In addition, CUE shows a positive correlation with SOC content. Our findings point to microbial CUE as a major determinant of global SOC storage. Understanding the microbial processes underlying CUE and their environmental dependence may help the prediction of SOC feedback to a changing climate.


Asunto(s)
Secuestro de Carbono , Carbono , Ecosistema , Microbiología del Suelo , Suelo , Carbono/análisis , Carbono/metabolismo , Cambio Climático , Plantas , Suelo/química , Conjuntos de Datos como Asunto , Aprendizaje Profundo
4.
J Appl Microbiol ; 133(4): 2375-2389, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35778976

RESUMEN

AIMS: To characterize the fermentation process and bacterial diversity of sorghum silage inoculated with Lactiplantibacillus plantarum LpAv, Pediococcus pentosaceus PpM and Lacticaseibacillus paracasei LcAv. METHODS AND RESULTS: Chopped sorghum was ensiled using the selected strains. Physicochemical parameters (Ammonia Nitrogen/Total Nitrogen, Dry Matter, Crude Protein, Acid Detergent Fibre, Neutral Detergent Fibre, Acid Detergent Lignin, Ether Extract and Ashes), bacterial counts, cell cytometry and 16sRNA sequencing were performed to characterize the ensiling process and an animal trial (BALB/c mice) was conducted in order to preliminary explore the potential of sorghum silage to promote animal gut health. After 30 days of ensiling, the genus Lactobacillus comprised 68.4 ± 2.3% and 73.5 ± 1.8% of relative abundance, in control and inoculated silages respectively. Richness (Chao1 index) in inoculated samples, but not in control silages, diminished along ensiling, suggesting the domination of fermentation by the inoculated LAB. A trend in conferring enhanced protection against Salmonella infection was observed in the mouse model used to explore the potential to promote gut health of sorghum silage. CONCLUSIONS: The LAB strains used in this study were able to dominate sorghum fermentation. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report using metaprofiling of 16sRNA to characterize sorghum silage, showing a microbiological insight where resident and inoculated LAB strains overwhelmed the epiphytic microbiota, inhibiting potential pathogens of the genus Klebsiella.


Asunto(s)
Lactobacillales , Sorghum , Amoníaco/metabolismo , Animales , Bacterias/genética , Bacterias/metabolismo , Detergentes , Grano Comestible/metabolismo , Éteres , Fermentación , Lactobacillales/genética , Lactobacillales/metabolismo , Lignina/metabolismo , Ratones , Nitrógeno/metabolismo , Extractos Vegetales , Ensilaje/microbiología , Sorghum/microbiología
5.
Antonie Van Leeuwenhoek ; 114(12): 2047-2063, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34609626

RESUMEN

The waste and by-products of the soybean industry could be an economic source of nutrients to satisfy the high nutritional demands for the cultivation of lactic acid bacteria. The aims of this work were to maximize the biomass production of Lacticaseibacillus paracasei 90 (L90) in three culture media formulated from an effluent derived from soy protein concentrate production and to assess the effects these media have on the enzymatic activity of L90, together with their influence on its fermentation profile in milk. The presence of essential minerals and fermentable carbohydrates (sucrose, raffinose, and stachyose) in the effluent was verified. L90 reached high levels of microbiological counts (∼ 9 log cfu mL-1) and dry weight (> 1 g L-1) on the three optimized media. Enzymatic activities (lactate dehydrogenase and ß-galactosidase) of L90, and its metabolism of lactose and citric acid, as well as lactic acid and pyruvic acid production in milk, were modified depending on the growth media. The ability of the L90 to produce the key flavour compounds (diacetyl and acetoin) was maintained or improved by growing in the optimized media in comparison with MRS.


Asunto(s)
Minerales , Proteínas de Soja , Biomasa , Medios de Cultivo , Fermentación
6.
Nutrients ; 11(7)2019 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-31319484

RESUMEN

This study analyzes an oral supplement of molecular iodine (I2), alone and in combination with the neoadjuvant therapy 5-fluorouracil/epirubicin/cyclophosphamide or taxotere/epirubicin (FEC/TE) in women with Early (stage II) and Advanced (stage III) breast cancer. In the Early group, 30 women were treated with I2 (5 mg/day) or placebo (colored water) for 7-35 days before surgery. For the Advanced group, 30 patients received I2 or placebo, along with FEC/TE treatment. After surgery, all patients received FEC/TE + I2 for 170 days. I2 supplementation showed a significant attenuation of the side effects and an absence of tumor chemoresistance. The control, I2, FEC/TE, and FEC/TE + I2 groups exhibited response rates of 0, 33%, 73%, and 100%, respectively, and a pathologic complete response of 18%, and 36% in the last two groups. Five-year disease-free survival rate was significantly higher in patients treated with the I2 supplement before and after surgery compared to those receiving the supplement only after surgery (82% versus 46%). I2-treated tumors exhibit less invasive potential, and significant increases in apoptosis, estrogen receptor expression, and immune cell infiltration. Transcriptomic analysis indicated activation of the antitumoral immune response. The results led us to register a phase III clinical trial to analyze chemotherapy + I2 treatment for advanced breast cancer.


Asunto(s)
Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Yodo/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/cirugía , Supervivencia sin Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Terapia Neoadyuvante , Proyectos Piloto , Oligoelementos/administración & dosificación
7.
Int J Food Microbiol ; 255: 17-24, 2017 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-28558330

RESUMEN

Spray-drying of lactic cultures provides direct-to-vat starters, which facilitate their commercialization and use. However, this process may alter the metabolic activity and deteriorate technological features. In this work, we assessed the influence of spray-drying on the survival and aroma production of two strains of mesophilic lactobacilli: Lactobacillus paracasei 90 and Lactobacillus plantarum 91, which have already been characterized as good adjunct cultures. The spray-drying was carried out using a laboratory scale spray and the dried cultures were monitored during the storage for the survival rate. The dried cultures were applied to two cheese models: sterile cheese extract and miniature soft cheese. The influence on the carbohydrate metabolism and the production of organic acids and volatile compounds was determined. Both strains retained high levels of viable counts in the powder after drying and during the storage at 5°C for twelve months. In addition, they also remained at high level in both cheese models during incubation or ripening. Similar profiles of carbohydrate fermentation and bioformation of volatile compounds were observed in the cheese extracts for each of the strains when tested as both fresh and dried cultures. In addition, the ability of Lb. paracasei 90 to increase the production of acetoin and diacetyl remarkably in cheese models was also confirmed for the spray-dried culture.


Asunto(s)
Queso/microbiología , Desecación , Manipulación de Alimentos/métodos , Manipulación de Alimentos/normas , Microbiología de Alimentos , Lactobacillus plantarum/fisiología , Lactobacillus/fisiología , Acetoína/metabolismo , Metabolismo de los Hidratos de Carbono , Queso/normas , Diacetil/metabolismo , Fermentación , Lactobacillus/metabolismo , Lactobacillus plantarum/metabolismo
8.
Braz. j. microbiol ; 47(3): 741-748, July-Sept. 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-788949

RESUMEN

ABSTRACT Aminotransferases and glutamate dehydrogenase are two main types of enzymes involved in the initial steps of amino acid catabolism, which plays a key role in the cheese flavor development. In the present work, glutamate dehydrogenase and aminotransferase activities were screened in twenty one strains of lactic acid bacteria of dairy interest, either cheese-isolated or commercial starters, including fifteen mesophilic lactobacilli, four thermophilic lactobacilli, and two streptococci. The strains of Streptococcus thermophilus showed the highest glutamate dehydrogenase activity, which was significantly elevated compared with the lactobacilli. Aspartate aminotransferase prevailed in most strains tested, while the levels and specificity of other aminotransferases were highly strain- and species-dependent. The knowledge of enzymatic profiles of these starter and cheese-isolated cultures is helpful in proposing appropriate combinations of strains for improved or increased cheese flavor.


Asunto(s)
Humanos , Streptococcus/enzimología , Glutamato Deshidrogenasa/metabolismo , Transaminasas/metabolismo , Lactobacillus/enzimología , Sistema Libre de Células , Activación Enzimática , Microbiología de Alimentos
9.
Braz J Microbiol ; 47(3): 741-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27266631

RESUMEN

Aminotransferases and glutamate dehydrogenase are two main types of enzymes involved in the initial steps of amino acid catabolism, which plays a key role in the cheese flavor development. In the present work, glutamate dehydrogenase and aminotransferase activities were screened in twenty one strains of lactic acid bacteria of dairy interest, either cheese-isolated or commercial starters, including fifteen mesophilic lactobacilli, four thermophilic lactobacilli, and two streptococci. The strains of Streptococcus thermophilus showed the highest glutamate dehydrogenase activity, which was significantly elevated compared with the lactobacilli. Aspartate aminotransferase prevailed in most strains tested, while the levels and specificity of other aminotransferases were highly strain- and species-dependent. The knowledge of enzymatic profiles of these starter and cheese-isolated cultures is helpful in proposing appropriate combinations of strains for improved or increased cheese flavor.


Asunto(s)
Glutamato Deshidrogenasa/metabolismo , Lactobacillus/enzimología , Streptococcus/enzimología , Transaminasas/metabolismo , Sistema Libre de Células , Activación Enzimática , Microbiología de Alimentos , Humanos
10.
Food Res Int ; 90: 259-267, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29195880

RESUMEN

Lactobacillus fermentum Lf2, an autochthonous strain isolated as a non starter culture in Cremoso cheese, produces high EPS levels (~1g/L) in optimized conditions (SDM broth, pH6.0, 30°C, 72h). Technological (texture profile and rheological analysis) and sensory properties of non-fat yogurts with 300 and 600mg EPS/L were studied at 3 and 25days after manufacture. Yogurts with different EPS concentrations showed higher hardness values than the control group at both periods of time, being the only significant difference that remained stable during time. The consistency index was also higher for the treated samples at both times evaluated, being significantly different for samples with 300mg/L of EPS extract, while the flow behavior index was lower for EPS-added yogurts. The thixotropic index was lower (P<0.05) for samples with the highest EPS extract concentration at the end of the storage time. Regarding the sensory analysis, those yogurts with 600mg/L of EPS extract presented the highest values of consistency at 3days of storage. No considerable differences for defects (milk powder, acid, bitter and cooked milk flavors) were perceived between treated and control samples at both times evaluated. Syneresis was also studied and samples with 600mg/L of EPS extract presented the lowest syneresis values at 25days of storage, which considerably decreased with the time of storage. In conclusion, the EPS from L. fermentum Lf2, used as an additive, provided yogurt with creamy consistency and increased hardness, without the presence of unwanted defects and improving the water holding capacity of the product. All the analysis done showed the potential of this extract to be used as a technofunctional natural ingredient, and it should be considered its positive impact on health, according to previous studies.

11.
Claves odontol ; 22(74): 17-24, sept. 2015. ilus
Artículo en Español | LILACS | ID: lil-775312

RESUMEN

Se plantean dos situaciones clínicas de pacientes adultos, hermanos, que presentan la misma maloclusión (Clase III con desviación mandibular hacia la izquierda), distinto sexo y biotipos faciales diferentes. En ellos queda de manifiesto en qué manera el patrón facial de cada individuo es determinante en la génesis de una maloclusión, teniendo una influencia directa en el pronóstico y plan de tratamiento. Uno de los casos se resolvió ortodóncicamente, con un tratamiento de compensación y extracción asimétrica del elemento 44, al tiempo que en el otro se efectuó un tratamiento ortodóncico-quirúrgico.


Asunto(s)
Humanos , Masculino , Adolescente , Femenino , Adulto Joven , Biotipología , Maloclusión de Angle Clase III/etiología , Maloclusión de Angle Clase III/terapia , Ortodoncia Correctiva/métodos , Asimetría Facial/cirugía , Extracción Dental/métodos , Desarrollo Maxilofacial , Cierre del Espacio Ortodóncico , Osteotomía/métodos , Planificación de Atención al Paciente , Pronóstico
12.
Rev Esp Geriatr Gerontol ; 47(6): 262-5, 2012.
Artículo en Español | MEDLINE | ID: mdl-22592162

RESUMEN

INTRODUCTION: At present, aging and increased life expectancy implies a greater susceptibility to dependence, which then leads to the irreversible loss of quality of life, in many cases due to chronic diseases such as osteoarthritis (OA). The aim of this study was to determine the effect of a treatment based on aerobic exercise in institutionalised elderly people diagnosed with knee osteoarthritis. MATERIAL AND METHOD: An experimental, prospective, single blind study was conducted. The sample (n=31), was divided into two groups. The experimental group (n=17) was treated based on aerobic exercise for 4 weeks with 2 sessions per week and each lasting 50minutes. We conducted a pre-test and post-test assessment using a visual analogue scale, WOMAC questionnaire and SF-36 as measuring instruments. The statistical program SPSS15.0 was used for the analysis of the data. RESULTS: We obtained significant differences in the t-test for paired samples in the three dimensions of the WOMAC questionnaire, P<.001, in the perceived pain P<.001 and in the physical function, vitality and mental health dimensions of the SF-36 with a 95% confidence interval. CONCLUSION: Exercise gave positive results in functional (pain, stiffness, physical function) and psychological aspects (mental health and vitality) in the institutionalised elderly.


Asunto(s)
Ejercicio Físico , Osteoartritis de la Rodilla/fisiopatología , Osteoartritis de la Rodilla/terapia , Calidad de Vida , Anciano de 80 o más Años , Femenino , Humanos , Institucionalización , Masculino , Estudios Prospectivos , Método Simple Ciego
13.
Cúspide (Córdoba) ; 2(2): 22-25, mar. 1999.
Artículo en Español | LILACS | ID: biblio-972884

RESUMEN

El gran desafío de la odontología actual, es poder lograr un equilibrio entre función, estética y persistencia en el tiempo de los resultados de nuestro tratamiento. La ausencia de la cúspide canina, es uno de los signos que nos indica desarmonía en la oclusión funcional y señala una alteración a nivel de los sectores posteriores, manifestándose como superficies abrasionadas, en especial en las cúspides fundamentales superiores e inferiores. Se producen como consecuencia de interferencias en los movimientos excéntricos laterales del lado del balance. Es por eso que la restauración debe realizarse respetando las normas básicas de la función, generando superficies de deslizamiento y evitando las de rozamiento, por ser estas últimas responsables de las abrasiones.


The great challenge of today's dentistry is to achieve a balance between function, aesthetics and persistence over time of the results of our treatment. The absence of canine cusp, is one of the signs that indicates disharmony in functional occlusion and indicates a disturbance at the level of the posterior sectors, manifesting as abraded surfaces, especially in the upper and lower core cusps. They occur as a result of interference with the lateral side eccentric movements balance. That's why the restoration should be done respecting the basic rules of the function, generating sliding surfaces and avoiding friction, the latter being responsible for abrasions.


Asunto(s)
Masculino , Femenino , Humanos , Adulto , Diente Canino/anomalías , Oclusión Dental , Retención de Dentadura , Articulación Temporomandibular/anomalías , Articulación Temporomandibular/crecimiento & desarrollo , Articulación Temporomandibular/lesiones
14.
Cuad. cir ; 10(1): 14-6, 1996. tab, graf
Artículo en Español | LILACS | ID: lil-208198

RESUMEN

El secuestro pulmonar es una anomalía congénita rara. En general representa el 1 a 2 por ciento de todas las resecciones pulmonares. Analizamos en forma retrospectiva las fichas clínica de 20 pacientes con diagnóstico postoperatorio de secuestro pulmonar, tratados en el Servicio de Cirugía del INER y CT durante 17 años, desde enero de 1977 a diciembre de 1993. Se estudiaron 13 (64 por ciento) hombres y 7 (35 por ciento) mujeres con una relación de 1,8:1. La media de edad fue de 40,8 años,con un margen de 15 a 63 años. Se estudiaron 17 secuestros intralobares y 3 extralobares. De ellos, 12 (60 por ciento) se ubicaron en el pulmón izquierdo y 8 (40 por ciento) en el pulmón derecho, con una relación de 1,5:1. La aortografía constituyó el método diagnóstico específico. El tratamiento fue quirúrgico. En los secuestros intralobares se realizó en un caso trisegmentectomía, en otro segmentectomía basal y en el resto lobectomía. En los secuestros extralobares se realizó extirpación del secuestro. Las complicaciones postoperatorias fueron dos empiemas pleurales tratados con drenajes, antibióticos y en un caso con toracotomía mínima. No hubo mortalidad en la serie


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Secuestro Broncopulmonar/diagnóstico , Aortografía , Broncografía , Secuestro Broncopulmonar/cirugía
15.
Cuad. cir ; 10(1): 24-7, 1996. ilus
Artículo en Español | LILACS | ID: lil-208829

RESUMEN

La fístula traqueoesofágica del adulto es poco frecuente, siendo su origen más común las neoplasias primarias malignas, lo que generalmente le confiere mal pronóstico. Cuando es causada por lesiones benignas el pronóstico es más favorable, siempre que se realice un adecuado tratamiento quirúrgico. Se presenta el caso de un hombre de 28 años que, a raíz de un accidente de tránsito, resultó politraumatizado. Entre sus lesiones se constató un traumatismo torácico y durante su hospitalización se descubrió una tuberculosis pulmonar, para la cual se inició tratamiento específico. Posterior al alta, fue reingresado diagnosticándose una fístula traqueoesofagíca. El tránsito esofágico mostró salida del medio de contraste a tráquea y bronquios, y la fibrobroncoscopía confirmó una lesión de 6 a 7 cm en el tercio medio de la parted posterior de la tráquea que se prolongaba hasta el bronquio fuente derecho. Fue operado de urgencia practicándose esofagectomía torácica, con esofagostoma cervical y gastrostomía transtorácica.La reparación de la porción membranosa de la tráquea requirió de una plastía que se realizó con 2 láminas de colágeno. El paciente evolucionó satisfactoriamente, con epitelización total de la superficie traqueal reparada al cabo de 60 días. El estudio histopatológico de la pieza operatoria reveló tuberculosis esofágica


Asunto(s)
Humanos , Masculino , Adulto , Fístula Traqueoesofágica/cirugía , Broncoscopía , Procedimientos Quirúrgicos Operativos , Toracotomía , Tráquea/cirugía , Tuberculosis/complicaciones
16.
Cuad. cir ; 10(1): 53-8, 1996. tab
Artículo en Español | LILACS | ID: lil-208835

RESUMEN

El empiema pleural se define como acúmulo de pus en la cavidad pleural. Su pronóstico está directamente relacionado con la precocidad del diagnóstico y con un oportuno y adecuado tratamiento. Un mal manejo del empiema puede llevar a la cronicidad de la infección y poner en peligro la vida del paciente. En este artículo se analizan algunos aspectos de esta patología incluyendo su etiología y su clasificación, Se describe el cuadro clínico y los exámenes que contribuyen al diagnóstico. Se analizan los objetivos del tratamiento y los procedimientos terapéuticos actualmente en uso para tratar esta afección


Asunto(s)
Humanos , Empiema Pleural/diagnóstico , Empiema Pleural/microbiología , Empiema Pleural/terapia , Toracoplastia/estadística & datos numéricos , Toracoscopía , Toracotomía/estadística & datos numéricos
17.
Cuad. cir ; 8(1): 76-81, 1994. tab
Artículo en Español | LILACS | ID: lil-207345

RESUMEN

El nemotórax es un motivo de consulta médica relativamente frecuente y es un cuadro que puede poner en peligro la vida de un paciente. Su origen obedece a variadas causas y su adecuado manejo requiere de un diagnóstico oportuno y de la ejecución de medidas terapéuticas efectivas. En este artículo se revisan algunos aspectos de esta patología incluyendo las diferentes clasificaciones, la etiología y la fisiología de esta lesión. Se describe el cuadro clínico y su diagnóstico, y se analizan las principales modalidades terapéuticas actualmente vigentes en el enfrentamiento de esta afección


Asunto(s)
Humanos , Neumotórax/diagnóstico , Neumotórax/clasificación , Neumotórax/terapia
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