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1.
Braz J Med Biol Res ; 55: e11820, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35588524

RESUMEN

The aim of the present study was to verify the role of lactate as a signaling molecule in cardiac tissue under physiological conditions. C57BL6/J male mice were submitted to acute running bouts on a treadmill at different exercise intensities (30, 60, and 90% of maximal speed - Smax) under the effect of two doses (0.5 and 5 mM) of α-cyano-4-hydroxycynnamate (CINN), a blocker of lactate transporters. Cardiac lactate levels, activity of the enzymes of glycolytic [hexokinase (HK) and lactate dehydrogenase (LDH)] and oxidative metabolism [citrate synthase (CS)], and expression of genes also related to metabolism [LDH, nuclear factor erythroid 2-related factor 2 (NRF-2), cytochrome oxidase IV (COX-IV), and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α)] were evaluated. Elevated cardiac lactate levels were observed after high intensity running at 90% of Smax, which were parallel to increased activity of the HK and CS enzymes and mRNA levels of PGC-1α and COX-IV. No changes were observed in cardiac lactate levels in mice running at lower exercise intensities. Interestingly, prior intraperitoneal administration (15 min) of CINN (0.5 mM) significantly reduced cardiac lactate concentration, activities of HK and CS, and mRNA levels of PGC-1α and COX-IV in mice that ran at 90% of Smax. In addition, cardiac lactate levels were significantly correlated to both PGC-1α and COX-IV cardiac gene expression. The present study provides evidence that cardiac lactate levels are associated to gene transcription during an acute bout of high intensity running exercise.


Asunto(s)
Condicionamiento Físico Animal , Factores de Transcripción , Animales , Citrato (si)-Sintasa/genética , Citrato (si)-Sintasa/metabolismo , Citrato (si)-Sintasa/farmacología , Expresión Génica , Ácido Láctico/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Músculo Esquelético/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Condicionamiento Físico Animal/fisiología , ARN Mensajero/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
2.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;55: e11820, 2022. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1374708

RESUMEN

The aim of the present study was to verify the role of lactate as a signaling molecule in cardiac tissue under physiological conditions. C57BL6/J male mice were submitted to acute running bouts on a treadmill at different exercise intensities (30, 60, and 90% of maximal speed - Smax) under the effect of two doses (0.5 and 5 mM) of α-cyano-4-hydroxycynnamate (CINN), a blocker of lactate transporters. Cardiac lactate levels, activity of the enzymes of glycolytic [hexokinase (HK) and lactate dehydrogenase (LDH)] and oxidative metabolism [citrate synthase (CS)], and expression of genes also related to metabolism [LDH, nuclear factor erythroid 2-related factor 2 (NRF-2), cytochrome oxidase IV (COX-IV), and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α)] were evaluated. Elevated cardiac lactate levels were observed after high intensity running at 90% of Smax, which were parallel to increased activity of the HK and CS enzymes and mRNA levels of PGC-1α and COX-IV. No changes were observed in cardiac lactate levels in mice running at lower exercise intensities. Interestingly, prior intraperitoneal administration (15 min) of CINN (0.5 mM) significantly reduced cardiac lactate concentration, activities of HK and CS, and mRNA levels of PGC-1α and COX-IV in mice that ran at 90% of Smax. In addition, cardiac lactate levels were significantly correlated to both PGC-1α and COX-IV cardiac gene expression. The present study provides evidence that cardiac lactate levels are associated to gene transcription during an acute bout of high intensity running exercise.

3.
Genet Mol Res ; 15(2)2016 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-27173225

RESUMEN

The aim of this study was to verify the adaptability and stability of soybean cultivars with regards to yield and oil content. Data of soybean yield and oil content were used from experiments set up in six environments in the 2011/12 and 2012/13 crop seasons in the municipalities of Patos de Minas, Uberaba, Lavras, and São Gotardo, Minas Gerais, Brazil, testing 36 commercial soybean cultivars of both conventional and transgenic varieties. The Wricke method and GGE biplot analysis were used to evaluate adaptability and stability of these cultivars. Large variations were observed in grain yield in relation to the different environments studied, showing that these materials are adaptable. The cultivars exhibited significant differences in oil content. The cultivars BRSGO204 (Goiânia) and BRSMG (Garantia) exhibited the greatest average grain yield in the different environments studied, and the cultivar BRSMG 760 SRR had the greatest oil content among the cultivars evaluated. Ecovalence was adopted to identify the most stable cultivars, and the estimates were nearly uniform both for grain yield and oil content, showing a variation of 0.07 and 0.01%, respectively. The GGE biplot was efficient at identifying cultivars with high adaptability and phenotype stability.


Asunto(s)
Grano Comestible/genética , Glycine max/genética , Aceites de Plantas/metabolismo , Adaptación Fisiológica/genética , Brasil , Grano Comestible/crecimiento & desarrollo , Ambiente , Genotipo , Estaciones del Año , Glycine max/crecimiento & desarrollo , Glycine max/metabolismo
4.
Allergol Immunopathol (Madr) ; 43(3): 272-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25796303

RESUMEN

BACKGROUND: PIDs are a heterogeneous group of genetic illnesses, and delay in their diagnosis is thought to be caused by a lack of awareness among physicians concerning PIDs. The latter is what we aimed to evaluate in Brazil. METHODS: Physicians working at general hospitals all over the country were asked to complete a 14-item questionnaire. One of the questions described 25 clinical situations that could be associated with PIDs and a score was created based on percentages of appropriate answers. RESULTS: A total of 4026 physicians participated in the study: 1628 paediatricians (40.4%), 1436 clinicians (35.7%), and 962 surgeons (23.9%). About 67% of the physicians had learned about PIDs in medical school or residency training, 84.6% evaluated patients who frequently took antibiotics, but only 40.3% of them participated in the immunological evaluation of these patients. Seventy-seven percent of the participating physicians were not familiar with the warning signs for PIDs. The mean score of correct answers for the 25 clinical situations was 48.08% (±16.06). Only 18.3% of the paediatricians, 7.4% of the clinicians, and 5.8% of the surgeons answered at least 2/3 of these situations appropriately. CONCLUSIONS: There is a lack of medical awareness concerning PIDs, even among paediatricians, who have been targeted with PID educational programmes in recent years in Brazil. An increase in awareness with regard to these disorders within the medical community is an important step towards improving recognition and treatment of PIDs.


Asunto(s)
Competencia Clínica/estadística & datos numéricos , Síndromes de Inmunodeficiencia/epidemiología , Médicos/estadística & datos numéricos , Brasil , Estudios Transversales , Cirugía General , Hospitales Generales , Humanos , Síndromes de Inmunodeficiencia/diagnóstico , Medicina Interna , Pediatría , Rol del Médico , Práctica Profesional , Encuestas y Cuestionarios
5.
Allergol Immunopathol (Madr) ; 40(6): 331-5, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22112535

RESUMEN

OBJECTIVES: To identify the main clinical manifestations, triggers, and treatment of severe allergic reactions (SAR) in children and adolescents (n=191, up to 18 years of age) seen by allergologists and registered in the Online Latin American Survey of Anaphylaxis (OLASA). RESULTS: 53.0% of the patients were males and the aetiological agent was identified in 85.5% of them as follows: foods (36.1%), drugs (27.7%), and insect stings (26.2%). The most common symptoms during an acute episode were cutaneous (94.2%), and respiratory (78.5%). Most patients were treated in emergency setting, yet only 34.6% received parenteral epinephrine and 14.3% had to be hospitalised. CONCLUSION: Cutaneous symptoms ranked the order of clinical presentation of SAR. Food was the main triggering agent in the younger cases and insect sting and drugs in the adolescents. Treatment provided for SAR was not appropriate. It is necessary to improve educational programmes in order to enhance the knowledge on this potentially fatal emergency.


Asunto(s)
Anafilaxia/epidemiología , Hipersensibilidad a las Drogas/epidemiología , Hipersensibilidad a los Alimentos/epidemiología , Mordeduras y Picaduras de Insectos/epidemiología , Adolescente , Anafilaxia/etiología , Niño , Preescolar , Recolección de Datos , Servicios Médicos de Urgencia , Femenino , Humanos , Lactante , Mordeduras y Picaduras de Insectos/complicaciones , América Latina/epidemiología , Masculino
6.
Environ Technol ; 32(5-6): 493-7, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21877529

RESUMEN

With the aim of searching for an in situ method for monitoring phenol, Agaricus bisporus tissue with tyrosine activity was used as a biocomponent and an oxygen electrode used as a transducer to develop a biosensor. The experimental methodology investigated the relation between dissolved oxygen and phenol concentration using a standard solution. Biosensor calibration was evaluated by studying reaction time and tissue amount necessary to promote a reliable response and to minimize errors. The influence of air saturation of the sample and washing of the electrode was also investigated. Results showed that 5 g of mushroom tissue with a 1 min reaction time promoted the best biosensor response within a phenol concentration range of 5-10 ppm. Washing of the electrode did not change the performance of the analysis; however, initial air saturation caused less variation amongst the samples.


Asunto(s)
Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Fenoles/análisis , Contaminantes Químicos del Agua/análisis , Agaricus/enzimología , Electrodos , Monofenol Monooxigenasa/metabolismo , Oxígeno/química , Reproducibilidad de los Resultados
7.
J Nutr Health Aging ; 15(7): 532-5, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21808930

RESUMEN

BACKGROUND: Brazilian population has passed for a process of demographic transition throughout latest years, characterized for the increase of the elderly population. Malnutrition is a serious problem to frail elderly. OBJECTIVE: The objective of this study was o evaluate the risk of malnutrition among institutionalized elderly resident in municipal shelters in the city of Rio de Janeiro, Brazil, using the tool Mini Nutritional Assessment (MNA). DESIGN: 344 institutionalized elderly aged over 60 years old were tested in a cross-sectional study using MNA. This tool classifies the nutricional status of the elderly in three groups: malnutrition (score < 17), risk of malnutrition (score 17 - 23,5) and well-nourished (score > = 24). Anthropometric measurements such as calf circumference (CC), mid-arm circumference (MAC) and Body mass index (BMI) were also evaluated. The variables were evaluated using the chi-square or ANOVA test. To correlate it was used Pearson's Correlation Coefficient (r). RESULTS: Mean age were 75.4 (+- 9.4) years old. Most of the elderly were female gender (59.6%). According to MNA 8.3% were with malnutrition, 55.6% at risk of malnutrition and 36.1% well-nourished. BMI classified 10.0% of the elderly as underweight. CC classified 10.0 % of them as inadequate in muscular mass. MNA was well correlated to BMI (r=0.412 p=0.000), age (r=-0.124 p=0.031), CC (r=0.399 p = 0.000) and MAC (r=0.391 p=0.000). CONCLUSION: Risk of malnutrition was high among the institutionalized elderly from public shelters in Rio de Janeiro - Brazil. MNA is a useful diagnostic tool for the identification on the frail elderly at risk of malnutrition.


Asunto(s)
Anciano Frágil , Evaluación Geriátrica , Desnutrición/epidemiología , Evaluación Nutricional , Sarcopenia/epidemiología , Encuestas y Cuestionarios , Delgadez/epidemiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Pesos y Medidas Corporales , Brasil/epidemiología , Estudios Transversales , Femenino , Viviendas para Ancianos , Humanos , Masculino , Desnutrición/diagnóstico , Estado Nutricional , Prevalencia , Riesgo
8.
Rev. bras. plantas med ; Rev. bras. plantas med;13(2): 197-202, 2011. ilus, tab
Artículo en Portugués | LILACS | ID: lil-596394

RESUMEN

Diversas espécies de Tabernaemontana têm sido estudadas devido a diversidade de alcalóides com atividade farmacológica. O objetivo desse trabalho foi avaliar a capacidade antimicrobiana in vitro do extrato das cascas do caule de Tabernaemontana catharinensis A. DC.em cepas de Staphylococcus aureus e Pseudomonas aeruginosa, microrganismos causadores de diversas infecções. Os testes de susceptibilidade bacteriana foram realizados usando o método de Kirby Bauer, consistindo na difusão em disco do antibiótico em meio de cultivo Mueller Hinton. Os testes de inibição foram realizados com soluções do extrato bruto seco de T. catharinensis dissolvido em etanol 70 por cento (v/v) na concentração 1,0 mg mL-1, que aplicada nos discos de área 20 mm², apresentaram concentração de 0,005 mg mm-2. Como controle negativo, realizou-se ensaios com placas contendo P. aeruginosa, e discos com etanol 70 por cento (v/v), e como controle positivo, discos com os antibióticos ceftriaxona sódica (0,25 mg mm-2 de área do disco), tetraciclina (0,005 mg mm-2) e cefalexina (0,005 mg mm-2). A solução do extrato na concentração de 0,005 mg mm-2 inibiu o Staphylococcus aureus, com diâmetro médio do halo de 0,6 cm. O halo de inibição para o Pseudomonas aeruginosa foi em média 1,2 cm. A tetraciclina, a cefalexina, e o controle negativo (etanol 70 por cento v/v) não demonstraram ação antimicrobiana. O halo de inibição usando ceftriaxona foi em média 2,2 cm para P. aeruginosa e 1,0 cm para Staphylococcus aureus.


Several Tabernaemontana species have been studied due to their several alkaloids with pharmacological activity. The aim of this work was to evaluate the in vitro antimicrobial action of the extract from stem barks of Tabernaemontana catharinensis A. DC. against strains of Staphylococcus aureus and Pseudomonas aeruginosa, microorganisms that cause several infections. Bacterial susceptibility tests were performed by the Kirby-Bauer method, consisting in antibiotic disk diffusion in Mueller Hinton medium. Inhibition tests were performed with solutions of T. catharinensis dry crude extract dissolved in ethanol 70 percent (v/v) at 1.0 mg mL-1, which became 0.005 mg mm-2 when applied to 20 mm² disks. As negative control, assays were carried out in plates containing P. aeruginosa and disks with ethanol 70 percent (v/v). Positive control consisted of disks containing the antibiotics ceftriaxone sodium (0.25 mg mm-2 disk area), tetracycline (0.005 mg mm-2) and cephalexin (0.005 mg mm-2). Extract solution at 0.005 mg mm-2 inhibited Staphylococcus aureus, with 0.6cm halo mean diameter. The inhibition halo for Pseudomonas aeruginosa was on average 1.2 cm. Tetracycline, cephalexin and negative control (ethanol 70 percent v/v) did not show antimicrobial action, whereas ceftriaxone sodium resulted in 2.2 and 1.0cm mean inhibition halo diameters for P. aeruginosa and Staphylococcus aureus, respectively.


Asunto(s)
Pruebas Antimicrobianas de Difusión por Disco , Técnicas In Vitro , Extractos Vegetales , Tabernaemontana , Brasil , Pseudomonas aeruginosa , Staphylococcus aureus
9.
Environ Technol ; 31(6): 611-6, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20540422

RESUMEN

Phenols are toxic compounds that are present in several industrial wastewaters, so their quantification has great environmental importance. In order to permit an analytical methodology for in situ monitoring, this work aims to study the application of Agaricus bisporus tissue as a source of tyrosinase and the optimum reaction conditions for the development of a phenol biosensor. Such an enzyme is a polyphenol oxidase that transforms many different phenolic compounds into quinones. Experiments with fungi tissue were performed to evaluate different sizes of tissue (0.5, 1.0 and 1.5 cm), different temperatures (23.5 degrees C to 60 degrees C), and different pH values (6, 7 and 8) to quantify analytically phenol content. Amongst the tested conditions, those that had presented larger efficiency in phenol oxidation were attained with the fungal tissue size of 1 cm, at pH 8.0, in the temperature range from 35 degrees C to 45 degrees C.


Asunto(s)
Agaricus/clasificación , Agaricus/enzimología , Técnicas Biosensibles/métodos , Monofenol Monooxigenasa/química , Monofenol Monooxigenasa/metabolismo , Fenol/análisis , Fenol/química , Activación Enzimática , Estabilidad de Enzimas , Especificidad de la Especie
10.
Braz J Med Biol Res ; 43(4): 325-9, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20445947

RESUMEN

(-)-Delta(9)-Tetrahydrocannabinol (Delta(9)-THC), a psychoactive component of marijuana, has been reported to induce oxidative damage in vivo and in vitro. In this study, we administered Delta(9)-THC to healthy C57BL/6J mice aged 15 weeks in order to determine its effect on hepatic redox state. Mice were divided into 3 groups: Delta(9)-THC (N = 10), treated with 10 mg/kg body weight Delta(9)-THC daily; VCtrl (N = 10), treated with vehicle [1:1:18, cremophor EL (polyoxyl 35 castor oil)/ethanol/saline]; Ctrl (N = 10), treated with saline. Animals were injected ip twice a day with 5 mg/kg body weight for 10 days. Lipid peroxidation, protein carbonylation and DNA oxidation were used as biomarkers of oxidative stress. The endogenous antioxidant defenses analyzed were glutathione (GSH) levels as well as enzyme activities of superoxide dismutase, catalase, glutathione S-transferase, glutathione reductase, and glutathione peroxidase (GPx) in liver homogenates. The levels of mRNA of the cannabinoid receptors CB1 and CB2 were also monitored. Treatment with Delta(9)-THC did not produce significant changes in oxidative stress markers or in mRNA levels of CB1 and CB2 receptors in the liver of mice, but attenuated the increase in the selenium-dependent GPx activity (Delta(9)-THC: 8%; VCtrl: 23% increase) and the GSH/oxidized GSH ratio (Delta(9)-THC: 61%; VCtrl: 96% increase), caused by treatment with the vehicle. Delta(9)-THC administration did not show any harmful effects on lipid peroxidation, protein carboxylation or DNA oxidation in the healthy liver of mice but attenuated unexpected effects produced by the vehicle containing ethanol/cremophor EL.


Asunto(s)
Dronabinol/farmacología , Peroxidación de Lípido/efectos de los fármacos , Hígado/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Psicotrópicos/farmacología , Animales , Hígado/enzimología , Ratones , Ratones Endogámicos C57BL , Oxidación-Reducción , Proteínas/análisis , Proteínas/efectos de los fármacos , ARN Mensajero/efectos de los fármacos , Receptores de Cannabinoides/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
11.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;43(4): 325-329, Apr. 2010. tab
Artículo en Inglés | LILACS | ID: lil-543579

RESUMEN

(-)-∆9-Tetrahydrocannabinol (∆9-THC), a psychoactive component of marijuana, has been reported to induce oxidative damage in vivo and in vitro. In this study, we administered (∆9-THC to healthy C57BL/6J mice aged 15 weeks in order to determine its effect on hepatic redox state. Mice were divided into 3 groups: (∆9-THC (N = 10), treated with 10 mg/kg body weight (∆9-THC daily; VCtrl (N = 10), treated with vehicle [1:1:18, cremophor EL® (polyoxyl 35 castor oil)/ethanol/saline]; Ctrl (N = 10), treated with saline. Animals were injected ip twice a day with 5 mg/kg body weight for 10 days. Lipid peroxidation, protein carbonylation and DNA oxidation were used as biomarkers of oxidative stress. The endogenous antioxidant defenses analyzed were glutathione (GSH) levels as well as enzyme activities of superoxide dismutase, catalase, glutathione S-transferase, glutathione reductase, and glutathione peroxidase (GPx) in liver homogenates. The levels of mRNA of the cannabinoid receptors CB1 and CB2 were also monitored. Treatment with ∆9-THC did not produce significant changes in oxidative stress markers or in mRNA levels of CB1 and CB2 receptors in the liver of mice, but attenuated the increase in the selenium-dependent GPx activity (∆9-THC: 8 percent; VCtrl: 23 percent increase) and the GSH/oxidized GSH ratio (∆9-THC: 61 percent; VCtrl: 96 percent increase), caused by treatment with the vehicle. ∆9-THC administration did not show any harmful effects on lipid peroxidation, protein carboxylation or DNA oxidation in the healthy liver of mice but attenuated unexpected effects produced by the vehicle containing ethanol/cremophor EL®.


Asunto(s)
Animales , Ratones , Peroxidación de Lípido/efectos de los fármacos , Hígado/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Psicotrópicos/farmacología , Dronabinol/farmacología , Hígado/enzimología , Oxidación-Reducción , Proteínas/análisis , Proteínas/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , ARN Mensajero/efectos de los fármacos , Receptores de Cannabinoides/efectos de los fármacos
12.
Biotechnol Bioeng ; 102(2): 425-35, 2009 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-18767189

RESUMEN

Current anthropogenic activities have been causing a significant increase in the atmospheric concentration of CO2 over the past 60 years. To mitigate the consequent global warming problem, efficient technological solutions, based on economical and technical grounds, are required. In this work, microalgae are studied as important biological systems of CO2 fixation into organic compounds through photosynthesis. These microorganisms are potential sources of a wide variety of interesting chemical compounds, which can be used for commercial purposes, reducing the cost of CO2 capture and sequestration. Specifically, Dunaliella salina culture was studied aiming at the impact evaluation of operational conditions over cellular growth and carotenoid production associated with the CO2 sequestration on focus. The main experimental parameters investigated were salinity and irradiance conditions. The experimental results supported the development of a descriptive mathematical model of the process. Based on the proposed model, a sensitivity analysis was carried out to investigate the operational conditions that maximize CO2 consumption and carotenoid production, in order to guide further development of technological routes for CO2 capture through microalgae. A preliminary cost estimation of CO2 sequestration combined to carotenoids production for a 200 MW power plant is presented, based on the growth rates achieved in this study.


Asunto(s)
Dióxido de Carbono/metabolismo , Carotenoides/biosíntesis , Chlorophyta/metabolismo , Técnicas de Cultivo de Célula , Chlorophyta/crecimiento & desarrollo , Chlorophyta/efectos de la radiación , Luz , Modelos Biológicos , Salinidad , Canales de Sodio
13.
Bioresour Technol ; 99(8): 3213-23, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-17669644

RESUMEN

An optimal operating mode for a sequencing batch reactor was determined via a model-based optimization. Synthetic wastewater containing mainly organic matter (as glucose) and nitrogen (as ammonium chloride) was treated without any addition of an external carbon source to accomplish denitrification step. A simplified model was used to describe process dynamics, comprised of six ordinary differential equations and an empirical correlation for oxygen consumption rate. Batch cycle time was the chosen objective function to be minimized for a fixed volume of waste to be treated. Furthermore, as SBR operation is divided in two major phases - aerobic and anoxic, to achieve total pollutants removal within minimum time, these phases can be repeatedly alternated. To ensure availability of organic matter necessary for denitrification, these two phases were combined with feed steps. Different feed strategies were tested using one, two or three feed steps. A successive quadratic programming algorithm was used, and maximum values for final COD, nitrate and ammonium concentrations, as well as maximum feed pump flow rate were some the process constraints. One step feed strategy was indicated by the optimization leading to a batch cycle time of 5h.


Asunto(s)
Reactores Biológicos , Nitrógeno/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Aerobiosis , Anaerobiosis , Biomasa , Diseño de Equipo , Cinética , Modelos Biológicos , Compuestos Orgánicos/análisis , Oxígeno/análisis , Compuestos de Amonio Cuaternario/análisis , Eliminación de Residuos Líquidos/instrumentación
14.
Am J Physiol Regul Integr Comp Physiol ; 294(1): R26-32, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17977919

RESUMEN

Sympathetic hyperactivity (SH) and renin angiotensin system (RAS) activation are commonly associated with heart failure (HF), even though the relative contribution of these factors to the cardiac derangement is less understood. The role of SH on RAS components and its consequences for the HF were investigated in mice lacking alpha(2A) and alpha(2C) adrenoceptor knockout (alpha(2A)/alpha(2C)ARKO) that present SH with evidence of HF by 7 mo of age. Cardiac and systemic RAS components and plasma norepinephrine (PN) levels were evaluated in male adult mice at 3 and 7 mo of age. In addition, cardiac morphometric analysis, collagen content, exercise tolerance, and hemodynamic assessments were made. At 3 mo, alpha(2A)/alpha(2C)ARKO mice showed no signs of HF, while displaying elevated PN, activation of local and systemic RAS components, and increased cardiomyocyte width (16%) compared with wild-type mice (WT). In contrast, at 7 mo, alpha(2A)/alpha(2C)ARKO mice presented clear signs of HF accompanied only by cardiac activation of angiotensinogen and ANG II levels and increased collagen content (twofold). Consistent with this local activation of RAS, 8 wk of ANG II AT(1) receptor blocker treatment restored cardiac structure and function comparable to the WT. Collectively, these data provide direct evidence that cardiac RAS activation plays a major role underlying the structural and functional abnormalities associated with a genetic SH-induced HF in mice.


Asunto(s)
Insuficiencia Cardíaca/fisiopatología , Modelos Genéticos , Receptores Adrenérgicos alfa 2/genética , Sistema Renina-Angiotensina/fisiología , Sistema Nervioso Simpático/fisiopatología , Angiotensina II/metabolismo , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Angiotensinógeno/metabolismo , Animales , Presión Sanguínea/fisiología , Modelos Animales de Enfermedad , Frecuencia Cardíaca/fisiología , Losartán/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Norepinefrina/sangre , Condicionamiento Físico Animal , Receptores Adrenérgicos alfa 2/efectos de los fármacos , Receptores Adrenérgicos alfa 2/fisiología
15.
Anal Chim Acta ; 595(1-2): 160-9, 2007 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-17605996

RESUMEN

Protozoa and metazoa are considered good indicators of the treatment quality in activated sludge systems due to the fact that these organisms are fairly sensitive to physical, chemical and operational processes. Therefore, it is possible to establish close relationships between the predominance of certain species or groups of species and several operational parameters of the plant, such as the biotic indices, namely the Sludge Biotic Index (SBI). This procedure requires the identification, classification and enumeration of the different species, which is usually achieved manually implying both time and expertise availability. Digital image analysis combined with multivariate statistical techniques has proved to be a useful tool to classify and quantify organisms in an automatic and not subjective way. This work presents a semi-automatic image analysis procedure for protozoa and metazoa recognition developed in Matlab language. The obtained morphological descriptors were analyzed using discriminant analysis, neural network and decision trees multivariable statistical techniques to identify and classify each protozoan or metazoan. The obtained procedure was quite adequate for distinguishing between the non-sessile protozoa classes and also for the metazoa classes, with high values for the overall species recognition with the exception of sessile protozoa. In terms of the wastewater conditions assessment the obtained results were found to be suitable for the prediction of these conditions. Finally, the discriminant analysis and neural networks results were found to be quite similar whereas the decision trees technique was less appropriate.


Asunto(s)
Árboles de Decisión , Análisis Discriminante , Eucariontes/citología , Procesamiento de Imagen Asistido por Computador/métodos , Redes Neurales de la Computación , Animales
16.
Water Res ; 41(12): 2581-9, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17399764

RESUMEN

A procedure for the semi-automatic identification of the main protozoa and metazoa species present in the activated sludge of wastewater treatment plants was developed. This procedure was based on both image processing and multivariable statistical methodologies, leading to the use of the image analysis morphological descriptors by discriminant analysis and neural network techniques. The image analysis program written in Matlab has proved to be adequate in terms of protozoa and metazoa recognition, as well as for the operating conditions assessment.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Invertebrados , Aguas del Alcantarillado , Animales , Eliminación de Residuos Líquidos/métodos
17.
Yeast ; 23(12): 867-77, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17001615

RESUMEN

In the present work, the surface characteristics of a wild-type strain of Yarrowia lipolytica (IMUFRJ50682) were investigated. Six different methods to characterize cell surfaces--adhesion to polystyrene; hydrophobic interaction chromatography (HIC); microbial adhesion to solvents (MATS) test; zeta potential; microbial adhesion to hydrocarbons (MATH) test; and contact angle measurement (CAM)--were employed to explain the cell surface behaviour of Y. lipolytica (IMUFRJ50682). This Y. lipolytica strain presents significant differences at the cell surface compared with another Y. lipolytica strain (W29) previously reported in the literature. The main difference is related to the higher cell adhesion to non-polar solvents. The proteins present on the cell wall of Y. lipolytica IMUFRJ50682 seem to play an important role in these particular surface characteristics because of the consistent reduction of this yeast hydrophobic character after the action of pronase on its cell wall.


Asunto(s)
Yarrowia/fisiología , Alcanos , Adhesión Celular/fisiología , Interacciones Hidrofóbicas e Hidrofílicas , Poliestirenos , Análisis Espectral , Propiedades de Superficie
18.
Environ Technol ; 27(11): 1209-15, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17203602

RESUMEN

Phenols are toxic pollutants found in industrial wastes imposing several risks to human health. Tyrosinase (EC 1.14.18.1) is an oxygenase oxyreductase found in several life forms, like the mushroom Agaricus bisporus. This enzyme is readily available from this fungal tissue leading to high activity extracts without extensive purification, thus suggesting its potential as a biocatalyst for applications involving biomodification of phenols or bioremediation of phenol-polluted waters. The purpose of this work was to employ a crude extract from the Agaricus bisporus mushroom and its biomass for the removal of phenol from polluted water. Experiments were carried out without pH control. The initial phenol concentration in all solutions was 100 mg l(-1). Four enzymatic concentrations (50, 100, 200 and 400 U ml(-1)) were tested. Reactions, with 200 U ml(-1) and 400 U ml(-1) enzymatic activity, led to 90% of phenol removal. Chitosan was used as a coagulant, but no significant improvement was observed. The in natura fungi was also able to remove 90% of phenol, demostrating its viability as a biocatalyst in bioremediation process.


Asunto(s)
Agaricus/enzimología , Monofenol Monooxigenasa/metabolismo , Fenoles/metabolismo , Contaminantes Químicos del Agua/metabolismo , Purificación del Agua/métodos , Agaricus/química , Animales , Artemia/efectos de los fármacos , Artemia/crecimiento & desarrollo , Biodegradación Ambiental , Biomasa , Fenoles/toxicidad , Pruebas de Toxicidad , Pez Cebra/crecimiento & desarrollo
19.
Environ Technol ; 25(11): 1313-20, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15617445

RESUMEN

The white rot fungus Trametes versicolor was applied to the decolourisation of three synthetic textile dyes in the presence and absence of glucose. Different initial dye concentrations were tested and approximately 97% decolourisation was achieved. It was found that fungal metabolism induced by the glucose as well as the pH play an important role in the decolourisation process. This treatment was also applied to a real wastewater from a textile industry-dyeing sector leading to 92% decolourisation.


Asunto(s)
Basidiomycota/fisiología , Industria Textil , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/metabolismo , Biodegradación Ambiental , Concentración de Iones de Hidrógeno
20.
Bioprocess Biosyst Eng ; 25(6): 371-5, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-13680341

RESUMEN

Stress conditions (thermal and oxidative) were applied to Yarrowia lipolytica culture. A rearrangement in cell metabolism as well as dimorphism was observed under these conditions. An image analysis procedure was employed for morphology characterization, and a net increase of around 25% on hyphae formation was detected. A significant increment in total hyphal length was detected, compared with the control system. The results obtained lead to the consideration of a possible relationship between dimorphism and a cell response mechanism to stress conditions.

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