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1.
Rev. int. med. cienc. act. fis. deporte ; 20(78): 197-210, jun. 2020. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-194777

RESUMO

OBJETIVO: determinar el efecto de una prueba aeróbica de natación en piscina clorada indoor sobre la concentración de NO2-, H2O2 y el pH en el condensado del aire espirado. MÉTODO: diez nadadores aficionados nadaron 2,5 km en piscina clorada. Se obtuvieron muestras antes y en cuatro oportunidades durante las ocho horas posteriores a la prueba. El análisis estadístico usó modelos mixtos y la prueba de Spearman RESULTADOS: la prueba se realizó a 74,99 ± 10,10 % de la reserva cardíaca y duró 50,80 ± 8,98 minutos. Posterior a la prueba disminuyó el NO2- (p = 0,04) y el pH (p = 0,02) en el condensado del aire espirado. Los valores pre-ejercicio se relacionaron con los cambios absolutos p = 0,0002, p = 0,047 y con el volumen de entrenamiento p = 0,017, p = 0,077 para NO2- y H2O2 respectivamente. CONCLUSIONES: la natación en piscina clorada disminuye la concentración de NO2- y el pH en el condensado del aire espirado


OBJECTIVE: to determine the effect of an aerobic swimming test in chlorinated indoor swimming pool on the concentration of NO2-, H2O2 and the pH in the exhaled breath condensate. METHODS: ten amateur swimmers swam 2,5 km in a chlorinated pool. Samples were obtained before and four times in the eight hours after the test. The statistical analysis used mixed models and the Spearman test. RESULTS: the test was performed at 74,99 ± 10,10 % of the cardiac reserve and lasted 50,80 ± 8,98 minutes. After the test the NO2- (p = 0,04) and the pH (p = 0,02) in the exhaled air condensate decreased. The pre-exercise values were related to the absolute changes p = 0,0002, p = 0.047 and with the training volume p = 0,017, p = 0.077 for NO2- and H2O2 respectively. CONCLUSIONS: Swimming in a chlorinated pool decreases the NO2-concentration and the pH in the exhaled breath condensate


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Natação/fisiologia , Expiração/fisiologia , Exercício Físico/fisiologia , Testes Respiratórios/métodos , Concentração de Íons de Hidrogênio , Nitritos , Piscinas , Pulmão/metabolismo , Oxidantes/metabolismo , Consumo de Oxigênio/fisiologia
2.
Int. microbiol ; 22(1): 19-28, mar. 2019. graf, tab
Artigo em Inglês | IBECS | ID: ibc-184810

RESUMO

Denitrifying bacteria carry out nitrate and nitrite respiration inside and outside the cell, respectively. In Thermus thermophilus, nitrate and nitrite transport processes are carried out by major facilitator superfamily (MFS) transporters. The sequence of the nar operon of nitrate-only respiring strains of T. thermophilus includes two tandemly organized MFS transporter genes (narK and narT) of the NarK1 and NarK2 families. Both can function as nitrate/nitrite antiporters, but NarK has been proposed as more specific for nitrate whereas NarT more specific for nitrite. In some nitrate- and nitrite-respiring strains of the same species, a single MFS transporter (NarO) belonging to a different MFS subfamily appears. To analyze the role of this single MFS in the same genetic context, we transferred the two types of nar operon to the aerobic strain HB27, and further included in both of them the ability to respire nitrite. The new denitrifying strains HB27dn, with two MFS, and HB27dp, with a single one, were used to isolate mutants devoid of transporters. Through in trans complementation experiments, we demonstrate that the NarO single MFS works efficiently in the transport of both nitrate and nitrite


No disponible


Assuntos
Nitratos/metabolismo , Desnitrificação , Proteínas de Membrana Transportadoras/metabolismo , Nitritos/metabolismo , Thermus thermophilus/enzimologia , Thermus thermophilus/genética , Deleção de Genes , Expressão Gênica , Ordem dos Genes , Proteínas de Membrana Transportadoras/genética , Óperon , Proteínas Recombinantes/metabolismo
4.
Clín. investig. arterioscler. (Ed. impr.) ; 29(3): 120-126, mayo-jun. 2017. graf
Artigo em Espanhol | IBECS | ID: ibc-162901

RESUMO

La insuficiencia cardíaca (IC) es un creciente problema médico por lo que resulta de interés el estudio de nuevos biomarcadores para su mejor caracterización, y en este sentido, evaluamos productos metabólicos (nitritos y nitratos) del óxido nítrico, especies reactivas del oxígeno (ROS), NADPH y superóxido dismutasa (SOD) y su posible valor predictivo en pacientes con IC. Además, estudiamos potenciales diferencias entre pacientes con y sin hipertensión pulmonar secundaria (HPS), considerados de peor pronóstico. En IC, demostramos disminución significativa de los niveles plasmáticos de nitritos y nitratos y SOD, mientras que ROS y NADPH se encontraban incrementados. Estos resultados concuerdan con los cambios fisiopatológicos propios de la IC. También demostramos en pacientes con IC e HPS que los niveles plasmáticos de nitritos y nitratos así como SOD estaban disminuidos respecto a IC sin HPS, mientras que ROS y NADPH estaban aumentados. Por lo tanto, nuestros resultados indican que óxido nítrico, ROS, NADPH y SOD podrían ser considerados como posibles marcadores en IC y además permitirían caracterizar a los pacientes con HPS (AU)


Heart failure (HF) is a growing medical problem and it is of interest to study new biomarkers for better characterisation. In this sense, nitric oxide, reactive oxygen species (ROS), NADPH, and superoxide dismutase (SOD) were evaluated, along with their possible predictive value in patients with HF. An analysis was also performed on the potential differences between patients with and without secondary pulmonary hypertension (SPH), considered to have a worse prognosis. A significant decrease of nitric oxide and SOD was noted in HF, whereas ROS and NADPH were increased. These results agree with the pathophysiological changes characteristic of HF. It was also demonstrated that in patients with HF and SPH that nitric oxide and SOD were decreased when compared to HF without SPH, whereas ROS and NADPH were increased. Therefore, our results suggest that nitric oxide, ROS, NADPH, and SOD, could be considered as possible markers in HF, and could also characterise patients with SPH (AU)


Assuntos
Humanos , Feminino , Masculino , Óxido Nítrico/análise , Insuficiência Cardíaca/diagnóstico , Hipertensão Pulmonar/etiologia , Disfunção Ventricular Esquerda/complicações , Biomarcadores/análise , Insuficiência Cardíaca/fisiopatologia , Nitritos/análise , Nitratos/análise , Espécies Reativas de Oxigênio/análise , NADP/análise , Superóxido Dismutase/análise , Estudos Transversais
5.
J. physiol. biochem ; 72(2): 353-360, jun. 2016. tab, graf
Artigo em Inglês | IBECS | ID: ibc-168279

RESUMO

Exercise promotes pulmonary oxidative imbalance. In this regard, some evidence has been obtained from the study of exhaled breath condensate (EBC) during urban races, in which the factors involved in the occurrence of this process are still not characterized. In this paper, under laboratory conditions, both the role of time of exercise on the generation of pro-oxidants (H2O2, NO2-) and pH have been assessed in EBC of 16 under-trained subjects who completed three tests of cycloergometric exercise at low intensity (30 % of VO2 max) with a duration of 10, 30, and 90 min. Samples were obtained as follows: immediately before and at 80 min post exertion in each test. In the 90-min test, an increase in H2O2, NO2- concentration in EBC at 80 min post exertion with no changes in the pH was observed. Total O2 consumption and total ventilation weakly correlated with the changes in H2O2 and NO2-. In conclusion, the concentration of pro-oxidants in the EBC depends on the duration of the exercise when it is performed at low intensity under laboratory conditions (AU)


No disponible


Assuntos
Humanos , Masculino , Adolescente , Adulto Jovem , Adulto , Oxidantes/metabolismo , Pulmão/metabolismo , Mucosa Respiratória/metabolismo , Exercício Físico , Taxa Respiratória , Peróxido de Hidrogênio/metabolismo , Fatores de Tempo , Nitritos/metabolismo , Consumo de Oxigênio , Ciclismo , Testes Respiratórios , Eliminação Pulmonar
6.
Rev. Rol enferm ; 38(10): 650-656, oct. 2015. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-143468

RESUMO

Introducción. El análisis de orina con tiras reactivas es una prueba muy usada en la clínica. Su uso más habitual es de confirmar o excluir la sospecha de infección de orina, pero también son útiles en la gestión de otras enfermedades. Desarrollo. Las tiras de orina más usadas disponen de 10 reactivos: leucocitos, nitritos, pH, glucosa, proteínas, cuerpos cetónicos, bilirrubina, urobilinógeno, densidad y sangre, para un análisis cualitativo y semicuantitativo de las muestras de orina. Se sumergirá en la muestra de orina y, tras esperar el tiempo indicado en el envase, se podrán interpretar los resultados, siempre teniendo en cuenta que hay un gran número de falsos positivos y negativos y que los resultados están influenciados por múltiples factores. Discusión. El uso más extendido de las tiras de orina es como ayuda diagnóstica ante la sospecha de infección, aunque la clínica nos oriente en gran medida. La probabilidad de tener infección de orina si hay disuria, frecuencia y urgencia miccional, hematuria, dolor suprapúbico y sensibilidad en la pelvis es de un 90 %. Si hay únicamente disuria y urgencia o frecuencia miccional la probabilidad disminuye a un 70-80 %, y si solo hay disuria, a un 25 %. Conclusiones. Las tiras de orina son un método rápido, fácil y barato para el diagnóstico y seguimiento de enfermedades, pero sus resultados son muy heterogéneos y están influenciados por factores externos, por lo que deben interpretarse con cautela. La sensibilidad y especificidad de las tiras de orina es muy variable según los estudios (S 46 %-86 % y E 17 %-93 %). Aunque los mayores valores diagnósticos se producen en las consultas de Atención Primaria, donde se estudia a una población más variada y se hace un mayor uso de las tiras, también es donde se requiere un mayor trabajo de diagnóstico diferencial por los numerosos falsos positivos. Se precisan más estudios con mayores especificaciones de los criterios seguidos y de las poblaciones estudiadas para llegar a determinar la verdadera sensibilidad y especificidad de las tiras de orina (AU)


Introduction. Urinalysis using reactive strip is a commonly used in clinical practice. Although mainly indicated as first step test when a urine infection it suspected, it may also be a helpful tool in the management of a wide range of disorders. Development. Standard urine test strips may comprise of up to 10 different chemical pads or reagents (leukocytes, nitrites, pH, glucose, proteins, ketones, bilirubin, urobilinogen, density and blood) that allow a qualitative and semiquantitative analysis of a urine sample. The test method consists of immersing the strip completely in a well-mixed sample of urine and left to stand for the time necessary for the reactions to occur (which is variable depending on the manufacturer). Finally the colors that appear are compared against a specific chromatic scale provided. Several factors may influence the results causing a significant number of false positives and negatives. Such limitations should always be taken into account when reading the test. Discussion. Despite clinical features lead to the suspicion of an infection, urine test strips is a fast screening test that may reinforce the diagnosis. The combination of dysuria, frequency and emergency, hematuria, pain and sensibility in the pelvis reaches a positive predictive value to identified a urine infection of 90 %. When only dysuria and emergency or high frequency are present, the such probability diminishes to 70-80 %, and, when dysuria is the only symptom, it drops to 25 %. Conclusions. Despite urine test strips is a fast, easy and cheap method for the diagnosis and follow-up of several diseases, results are fairly heterogeneous and may be influenced by external factors. Therefore a cautious interpretation if advised. Sensibility and specificity of urine test strips is widely variable (S 46 %-8 6% and E 17 %-93 %). Although the highest diagnostic values are obtained at primary care centers, where such tests are routinely used in a diverse population, the number of false positives is still high. This issue should be taken into account and a proper differential diagnosis of a positive result is mandatory in all cases (AU)


Assuntos
Feminino , Humanos , Masculino , Urina/microbiologia , Urinálise/métodos , Urinálise/enfermagem , Infecções Urinárias/diagnóstico , Infecções Urinárias/enfermagem , Infecções Urinárias/urina , Fitas Reagentes , Sensibilidade e Especificidade , Atenção Primária à Saúde/métodos , Glucose , Bilirrubina , Cetonas , Concentração de Íons de Hidrogênio , Sangue , Proteínas , Nitritos/isolamento & purificação , Leucócitos/microbiologia , Ácido Ascórbico
7.
Nutr. hosp ; 32(4): 1493-1499, oct. 2015. tab
Artigo em Inglês | IBECS | ID: ibc-143641

RESUMO

Aim: to evaluate the serum concentration of NO in overweight women, smokers (SG) and nonsmokers (NSG). Methods: blood samples from smokers (n = 20) and nonsmokers (n = 18) were collected to obtain serum, and stored at -80 ºC until analysis. NO was assessed by measuring total nitrite, determined by Greiss method. It was adopted as reference 24.4 µmol/L, mean value found in a study with healthy subjects without excess weight. We used the Student t test to compare the means of age and waist circumference, and the Mann-Whitney U test to compare the median of concentrations of nitrite, number of cigarettes/day and Body Mass Index. We adopted a significance level of p<0.05. Results: the median nitrite in SG was 16.53 (2.79 - 69.72) µmol/L, whereas in NSG was 10.85 (1.44 - 43.25) µmol/L (p = 0.028). BMI median value to SG and NSG, was respectively 29.50 (25.00 - 38.14) kg/m2 and 30.68 (25.10 - 36.98) kg/m2 (p = 0.530), being classified as overweight. The data showing that the average nitrite was below the estimated value for healthy individuals. Conclusion: the results indicate a decrease of NO metabolites in women with excess weight, independently of being smoker. Despite the significant difference found between groups, these women had values well below the reference value of NO for healthy women. Therefore, it seems that smoking does not interfere in nitrite levels in patients already compromised by obesity (AU)


Objetivo: evaluar la concentración sérica de NO en las mujeres con sobrepeso, fumadoras (SG) y no fumadoras (GSN). Método: se recogieron muestras de sangre de las fumadoras (n = 20) y no fumadoras (n = 18) para obtener el suero, y se almacenaron a -80 °C hasta su análisis. NO se evaluó mediante la medición total de nitrito, determinado por el método Greiss. Fue adoptado como referencia de 24,4 µmol/L, valor medio que se encuentra en un estudio con sujetos sanos sin exceso de peso. Se utilizó la prueba t de Student para comparar las medias de edad y la circunferencia de la cintura, así como la prueba de Mann-Whitney para comparar la mediana de las concentraciones de nitrito, número de cigarrillos/día y el Índice de Masa Corporal. Hemos adoptado un nivel de significación de p<0.05. Resultados: la mediana de SG nitrito fue 16,53 (2,79- 69,72) mol/L, mientras que en NSG fue 10,85 (1,44-43,25) µmol/L (p = 0,028). El IMC valor de la mediana de SG y NSG fue, respectivamente, 29,50 (25,00-38,14) kg/m2 y 30,68 (25,10-36,98) kg/m2 (p = 0,530), siendo clasificado como sobrepeso. Los datos muestran que el nitrito promedio estuvo por debajo del valor estimado para individuos sanos. Conclusiones: los resultados indican una disminución de los metabolitos NO en las mujeres con exceso de peso, independientemente de si son fumadoras o no. A pesar de la diferencia significativa entre los grupos, estas mujeres tenían valores muy por debajo del valor de referencia del NO para las mujeres sanas. Por lo tanto, parece que el fumar no interfiere en los niveles de nitritos en pacientes que ya están comprometidas por la obesidad (AU)


Assuntos
Feminino , Humanos , Óxido Nítrico/sangue , Sobrepeso/fisiopatologia , Tabagismo/fisiopatologia , Fumar/epidemiologia , Nitritos/isolamento & purificação , Inflamação/fisiopatologia
8.
Rev. Rol enferm ; 38(7/8): 504-510, jul.-ago. 2015. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-138369

RESUMO

Por estudios realizados en nuestro hospital, se observó que todos los años existía una diferencia considerable entre las infecciones de orina en pacientes sondados del servicio de Neurología con respecto a otras unidades de hospitalización. Esto nos llevó a realizar el presente estudio. Objetivo. Determinar las causas que aumentan las infecciones del tracto urinario (ITU) en el paciente sondado con patología neurológica. Metodología. Estudio observacional descriptivo prospectivo de 50 pacientes con patología neurológica ingresados en la planta de Neurología del Hospital de Cabueñes (Gijón), que precisaron sondaje vesical (SV). El trabajo de campo consistió en recoger una muestra para sedimento y cultivo de orina pre y post-SV, además de anotar las causas del sondaje, duración, edad, sexo y diagnóstico en una hoja de registro. Se descartaron aquellos pacientes sondados de urgencias, los que estaban tomando antibiótico y aquellos cuya patología no era neurológica. Resultados. De 50 pacientes estudiados que precisaron SV, el 40 % fue por retención de orina, un 40 % por orden médica y el 20 % por tratamiento con manitol. El 88 % tuvo un diagnóstico de ictus. Un 12 % ya tenía el cultivo positivo antes de ser portadores de SV. Conclusiones. El ictus es la patología neurológica que más precisa SV. Una de las causas más importantes de aquel es la retención de orina. Algunos de los pacientes sondados ya tenían ITU antes de la colocación de SV (AU)


In previous studies carried out in our hospital (Hospital de Cabueñes, Gijón, Spain) it could be noticed/stated that every year there was a considerable difference between the patients with urine catheterization in the Neurology Service and the patients in the other hospital wards. This encourages us to carry out the following research. Objectives. The purpose of this study is to determine the causes that increase the urinary infections in neurological patients with bladder catheterization compared to catheterized patients with other diseases. Analysis of sediment and urine culture before and after the urinary bladder catheterization. Methods. Retrospective, descriptive and observational study of fifty patients with neurological disorders who were hospitalized in the neurological care unit of Hospital de Cabueñes (Gijón, Spain) and who needed urinary catheterization. The fieldwork consisted of collecting a sample for sediment and culture before and after the urinary catheterization and also of registering the causes of the catheterization, the length of the treatment, age and sex of patients on a medical record sheet. Patients who were catheterized in the Emergency (A&E) unit, those who were taking antibiotics and those who did not suffer a neurological disease did not take part in this study. Results. 20 patients (40 %) out of the 50 who took part in this study and who needed urinary catheterization (UC) suffered from urinary retention, another 20 (40 %) were under medical diagnosis and supervision and the last 10 (20 %) were treated with manitol. 44 patients (88 %) were diagnosed with strokes. 12 % of them had a positive culture prior to UC placement. Conclusions. Patients who suffered stokes have a high risk of urine retention due to their functional disability. Some of them had already the urine values altered, they even had infection prior to the urinary catheter placement (AU)


Assuntos
Feminino , Humanos , Masculino , Infecções Urinárias/enfermagem , Infecções Urinárias/prevenção & controle , Doenças do Sistema Nervoso/complicações , Doenças do Sistema Nervoso/enfermagem , Doenças do Sistema Nervoso/patologia , Infecções Urinárias/reabilitação , Infecções Urinárias/etiologia , Estudos Prospectivos , Manitol/uso terapêutico , Sonda de Prospecção , Acidente Vascular Cerebral/enfermagem , Acidente Vascular Cerebral/prevenção & controle , Nitritos/uso terapêutico , Leucócitos
10.
Arch. Soc. Esp. Oftalmol ; 89(8): 313-315, ago. 2014. ilus
Artigo em Espanhol | IBECS | ID: ibc-126031

RESUMO

CASO CLÍNICO: Se describe un caso de maculopatía por popper. DISCUSIÓN: Popper es una droga compuesta por varias formas de nitritos de alquilo. Un varón de 39 años, consumidor de popper durante años, acude a la consulta por fosfenos, pérdida de agudeza visual y un escotoma central. El SD-OCT en el ojo derecho presenta pérdida de continuidad a nivel de la línea SI/SE. El SD-OCT del ojo izquierdo muestra un agujero macular externo de aspecto rectangular y con bordes rectos, y un quiste macular externo


CASE REPORT: A case of maculopathy due to «poppers» is described. DISCUSSION: Poppers is a drug composed of various forms of alkyl nitrite. A 39 year-old man, who had been using poppers for years, was seen in the clinic with phosphenes, reduced visual acuity and central scotoma. The SD-OCT in the right eye showed disruption at the level of the IS/OS junction line. The SD-OCT scan in the left eye showed an outer rectangular retinal hole and an outer retinal


Assuntos
Humanos , Masculino , Adulto , Drogas Desenhadas/efeitos adversos , Doenças Retinianas/induzido quimicamente , Administração por Inalação , Nitritos/efeitos adversos , Resíduos Voláteis
11.
Pediatr. aten. prim ; 16(61): 65-69, ene.-mar. 2014.
Artigo em Espanhol | IBECS | ID: ibc-121760

RESUMO

Pese a que el consumo de verduras y hortalizas es recomendable tanto en adultos como en bebés y niños pequeños, existe el riesgo de que estos últimos ingieran a través de dichos alimentos cantidades elevadas de nitratos que incrementen el riesgo de padecer metahemoglobinemia. Aunque la ingesta media de nitratos en la población infantil europea no supera los márgenes de seguridad, un análisis llevado a cabo por la Autoridad Europea de Seguridad Alimentaria (EFSA) en 2010 reveló que el consumo de espinacas puede estar implicado en ciertos casos de metahemoglobinemia infantil. La Agencia Española de Seguridad Alimentaria y Nutrición (AESAN) consideró en 2011 que las acelgas, debido a su notable consumo en España, también pueden suponer un riesgo para la población infantil si su ingesta es elevada. A las recomendaciones de la AESAN, que es conveniente que conozca cualquier profesional sanitario del ámbito de la nutrición infantil, resulta prudente añadir que un elevado consumo de borraja (Borago officinalis, una hortaliza muy consumida en Navarra, La Rioja y Aragón en la elaboración de purés hechos en casa) también puede estar implicado en la metahemoglobinemia infantil. En cualquier caso, tal y como señalan tanto la EFSA como la AESAN, cuando se comparan los riesgos/beneficios de la exposición de nitratos por el consumo de verduras y hortalizas, prevalecen los efectos beneficiosos de su consumo (AU)


Although the consumption of vegetables is recommended for adults, infants and young children, there is a risk that their consumption results in a high intake of nitrates that increases the risk of methemoglobinemia. Even though the average nitrate intake in children does not exceed the European safety threshold, an analysis conducted by the European Food Safety Authority (EFSA) in 2010 revealed that the consumption of spinach may be involved in certain cases of infant methemoglobinemia. The Spanish Agency for Food Safety and Nutrition (AESAN) found in 2011 that chards, because of its remarkable consumption in Spain, may also pose a risk for children. In addition to the AESAN recommendations, that any health care professional in the field of infant nutrition should know, it is prudent to add that a high consumption of borage (Borago officinalis, a vegetable widely consumed in Navarra, La Rioja and Aragón in homemade purees) may also be involved in infant methemoglobinemia. In any case, and as EFSA and AESAN point out, the benefits of eating vegetables prevail over the risks of the exposure to nitrates linked to their consumption (AU)


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Nitratos/administração & dosagem , Nitratos/efeitos adversos , Nitratos/metabolismo , Metemoglobinemia/complicações , Metemoglobinemia/epidemiologia , Nitritos/administração & dosagem , Nitritos/efeitos adversos , Verduras/efeitos adversos , Verduras/metabolismo , Dieta/efeitos adversos , Dieta/métodos , Dieta , Nutrição do Lactente/normas , Nutrição da Criança , Atenção Primária à Saúde/métodos , Atenção Primária à Saúde
12.
J. investig. allergol. clin. immunol ; 23(1): 7-3, ene.-feb. 2013. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-111764

RESUMO

Antecedentes: Los leucotrienos (LT), isoprostanos y nitritos/nitratos, que son biomarcadores de la inflamación de las vías aéreas, y el estrés oxidativo, pueden ser detectados en el condensado del aire exhalado (CAE). El objetivo de este estudio fue evaluar el LTB4, LTE4, 8-isoprostano, nitritos y nitratos en el CAE de niños preescolares sanos y con sibilancias. Material y métodos: Se realizó un estudio transversal en el que se incluyeron 21 niños sanos no atópicos y 25 pacientes con sibilancias recurrentes. El LTB4, LTE4 y 8-isoprostano, se midieron en el CAE mediante enzimoinmunoensayo, y los nitritos/nitratos mediante método colorimétrico. Resultados: Las concentraciones de LTB4 fueron mayores en los niños con episodios de sibilancias que en controles sanos (76 pg/ml vs 20 pg/ml, p<0,001); El LTE4 se incrementó también en niños con episodios de sibilancias en comparación con niños sanos (68 pg/ml vs 35 pg/ml, p<0,001). Las concentraciones de nitritos fueron mayores en los niños con episodios de sibilancias que en los controles (14 pg/ml vs 9,7 pg/ml, p<0,03). No hubo diferencias en las concentraciones de 8-isoprostano y nitratos entre el grupo de niños enfermos y el grupo control. Conclusiones: Nuestros hallazgos sugieren que el CAE es un método no invasivo para la evaluación de la inflamación de las vías respiratorias y del estrés oxidativo en lactantes y niños en edad preescolar. Las concentraciones de LTB4, LTE4 y de nitritos, se incrementaron en niños con episodios recurrentes de sibilancias en comparación con los controles sanos (AU)


Background: Leukotrienes (LT), isoprostanes, and nitrites/nitrates are biomarkers of airway inflammation and oxidative stress that can be detected in exhaled breath condensate (EBC). The aim of this study was to evaluate LTB4, LTE4, 8-isoprostane, and nitrite/nitrate levels in the EBC of healthy and wheezing preschool children. Methods: We included 21 healthy nonatopic children and 25 patients with recurrent wheezing episodes in a cross-sectional study. LTB4, LTE4, and 8-isoprostane concentrations were measured directly in EBC using a specific enzyme immunoassay; nitrite/nitrate concentrations were measured using a colorimetric assay. Results: LTB4 concentrations were higher in children with wheezing episodes than in healthy controls (76 pg/mL vs 20 pg/mL, P<.001). LTE4 was increased in children with wheezing episodes than in healthy controls (68 pg/mL vs 35 pg/mL, P<.001). Nitrite concentrations were higher in children with wheezing episodes than in healthy controls (14 pg/mL vs 9.7 pg/mL, P<.03). We found no differences in 8-isoprostane and nitrate concentrations between the patients and the healthy controls. Conclusions: Our findings suggest that EBC is a suitable noninvasive method for the assessment of airway inflammation and oxidative stress in preschool children. Levels of LTB4, LTE4, and nitrites were higher in children with recurrent wheezing episodes than in healthy controls (AU)


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Inflamação/fisiopatologia , Expiração/imunologia , Isoprostanos/análise , Leucotrienos/análise , Nitritos/análise , Nitratos/análise , Biomarcadores/análise , Estresse Oxidativo , Fatores de Risco , Sons Respiratórios/fisiopatologia
13.
Int. microbiol ; 15(3): 111-119, sept. 2012. graf, tab
Artigo em Inglês | IBECS | ID: ibc-136881

RESUMO

Haloferax mediterranei is a denitrifying halophilic archaeon able to reduce nitrate and nitrite under oxic and anoxic conditions. In the presence of oxygen, nitrate and nitrite are used as nitrogen sources for growth. Under oxygen scarcity, this haloarchaeon uses both ions as electron acceptors via a denitrification pathway. In the present work, the maximal nitrite concentration tolerated by this organism was determined by studying the growth of H. mediterranei in minimal medium containing 30, 40 and 50 mM nitrite as sole nitrogen source and under initial oxic conditions at 42 °C. The results showed the ability of H. mediterranei to withstand nitrite concentrations up to 50 mM. At the beginning of the incubation, nitrate was detected in the medium, probably due to the spontaneous oxidation of nitrite under the initial oxic conditions. The complete removal of nitrite and nitrate was accomplished in most of the tested conditions, except in culture medium containing 50 mM nitrite, suggesting that this concentration compromised the denitrification capacity of the cells. Nitrite and nitrate reductases activities were analyzed at different growth stages of H. mediterranei. In all cases, the activities of the respiratory enzymes were higher than their assimilative counterparts; this was especially the case for NirK. The denitrifying and possibly detoxifying role of this enzyme might explain the high nitrite tolerance of H. mediterranei. This archaeon was also able to remove 60 % of the nitrate and 75 % of the nitrite initially present in brine samples collected from a wastewater treatment facility. These results suggest that H. mediterranei, and probably other halophilic denitrifying Archaea, are suitable candidates for the bioremediation of brines with high nitrite and nitrate concentrations (AU)


No disponible


Assuntos
Haloferax mediterranei/enzimologia , Haloferax mediterranei/crescimento & desenvolvimento , Haloferax mediterranei/metabolismo , Nitratos/metabolismo , Nitrito Redutases/metabolismo , Nitritos/metabolismo , Comércio/metabolismo , Eliminação de Resíduos Líquidos/métodos , Desnitrificação , Recuperação e Remediação Ambiental/métodos , Oxirredução , Águas Residuárias/microbiologia
15.
Inmunología (1987) ; 28(4): 161-172, oct.-dic. 2009. ilus
Artigo em Inglês | IBECS | ID: ibc-108258

RESUMO

En este estudio se investiga la eficacia de M. tuberculosis muerto porcalor (Mtbi) y las Proteinas del Filtrado del Cultivo (PFC) en la activación de las células mononucleares (MC) y polimorfonucleares neutrolilos (PMN)de sangre periférica de pacientes tuberculosos. Se evalua en 16 pacientes tuberculosos, HIV- y 12 controles sanos el Estallido Respiratorio, los metabolitos derivados del NO y la producción de IL-2, IL-12 y TNFeÁ por las células estimuladas. Se detecta un incremento en la concentración de TNFeÁ en el sobrenadante de cultivo (s.c.) de PMN al comparar con los valoresbasales y en la evaluada en s.c. de MC y PMN estimulados, al ser comparadas con las del grupo control, excepto para los neutrófilos estimuladoscon PFC. Se mostraron niveles aumentados de IL-12 e IL-2 en s.c. de ambas células, MC y PMN estimuladas por en PTB, mientras que no se hallarondiferencias en los s.c. de los controles. Los valores basales de Estallido Respiratorio (RB) detectada en MC y PMN de pacientes no difirieron significantivamente de los correspondientes al grupo control. La expresión del Estallido Respiratorio en ambos tipos celulares fue menor en los pacientes que en los controles, independientemente del estímulo empleado. Sedeterminaron concentraciones de nitritos más elevadas en los sobrenadantesde las MC estimuladas con Mtbi y PFC provenientes de pacientes, comparadas con las de los controles. Los datos obtenidos relacionados al estímulo de la respuesta celular, nos proporcionan información sobre la inmunidad protectiva contra el M. tuberculosis y, a la vez, aportan algunos recursos útiles para una terapia anti-tuberculosa más eficiente (AU)


The efficacy of heat-killed Mycobacterium tuberculosis (HKMtb) andits culture filtrate proteins (CFP) to activate blood mononuclear cells (MC)and polymorphonuclear neutrophils (PMN) from tuberculosis patientswas investigated. Respiratory burst, NO-derived metabolites, IL-2, IL-12and TNF-¦Á production of stimulated cells from 16 HIV- tuberculosispatients and 12 healthy controls were analyzed. Increased amounts ofTNF-¦Á in supernatants from baseline and stimulated polymorphonuclear and mononuclear cells of tuberculosis patients were detected whencompared with controls, except for CFP stimulated neutrophils. Augmented IL-2 and IL-12 levels were observed in supernatants of both stimulated MC and PMN from TBP while no differences were found in control supernatants. The patients had a lower respiratory burst responsethan the controls, for both cell types, regardless of the stimulus employed. Higher nitrite concentrations were found in HKMtb- and CFP-stimulated mononuclear supernatants from patients, compared with controls. The obtained data of the stimulated cellular responses provides usinformation about the protective immunity against Mycobacterium tuberculosis and some resources to obtain a more efficient anti-tuberculous therapy (AU)1


Assuntos
Humanos , Tuberculose/imunologia , Mycobacterium tuberculosis/patogenicidade , Explosão Respiratória/imunologia , Proteínas de Bactérias/imunologia , Nitritos/análise , Citocinas/análise , Fator de Necrose Tumoral alfa/análise , Interleucina-2/análise , Interleucina-12/análise
16.
J. physiol. biochem ; 63(3): 231-238, jul.-sept. 2007.
Artigo em Inglês | IBECS | ID: ibc-76680

RESUMO

Fluid absorption from the proximal jejunum of the anaesthetised rat was measuredin vivo by fluid recovery. As expected, heat stable (STa) enterotoxin fromE.coli reduced fluid absorption. Neither intraperitoneal L-NAME, thought to inhibita putative neurally mediated action of STa, nor similar doses of D-NAME,ameliorated the inhibitory effect on jejunal fluid absorption of STa. Luminally perfused10 mM sodium nitroprusside (SNP) had no effect on fluid absorption whenexpressed per gram dry weight per hour but reduced fluid absorption whenexpressed per cm length per hour. Similarly, 80 but not 40 mg/Kg of L-NAMEreduced fluid absorption when expressed per cm length per hour, while the samedose of D-NAME did not. L-NAME and SNP significantly increased the wet weightto dry weight and the length to dry weight ratio of perfused loops. We conjecturethat smooth muscle relaxation caused by these compounds increases interstitial fluidvolumes that can be misconstrued as changes in absorption when this is expressed percm length or per tissue wet weight. When fluid absorption is expressed per gram dryweight of tissue, there is no evidence for a role of nitric oxide in normal or STa inhibitedfluid absorption (AU)


No disponible


Assuntos
Animais , Feminino , Ratos , Toxinas Bacterianas/farmacologia , Enterotoxinas/farmacologia , Absorção Intestinal , Jejuno/fisiologia , Óxido Nítrico/fisiologia , Toxinas Bacterianas/antagonistas & inibidores , Enterotoxinas/antagonistas & inibidores , Jejuno/anatomia & histologia , Jejuno , NG-Nitroarginina Metil Éster/farmacologia , Nitritos/metabolismo , Nitroprussiato/farmacologia , Ratos Sprague-Dawley , Estereoisomerismo
17.
Nefrología (Madr.) ; 27(3): 329-334, mayo-jun. 2007. tab
Artigo em Es | IBECS | ID: ibc-057325

RESUMO

Introducción y objetivos: La Hipertensión gestacional -HG-y la preeclampsia -P- son estados hipertensivos del embarazo cuyo mecanismo patogénico no se conoce. Este estudio pretende definir patrones de comportamiento que expliquen el origen de las diferencias entre embarazadas hipertensas y con preeclampsia mediante el análisis de determinados factores vasoactivos. Diseño del estudio: Estudio caso-control basado en casos incidentes. Material y métodos: Se seleccionaron de forma consecutiva dos grupos de pacientes, HG (n = 21) y P (n = 21). Por cada paciente problema se incluyó una gestante normal de similar edad y semana de gestación. Se obtuvieron dos grupos control, uno con respecto al grupo de pacientes HG y otro en relación a las pacientes P. A cada mujer se le realizó estudio de bioquímica, hemograma, coagulación, y cuantificación de los factores vasoactivos endotelina, nitritos y GMPc, así como la excreción urinaria de adrenalina y noradrenalina. Se compararon los resultados de cada grupo de pacientes (HG y P) con su respectivo grupo control. Resultados: La tensión arterial sistólica y diastólica fueron superiores en las pacientes con hipertensión (HG y P) en comparación con sus controles. Igualmente, en las pacientes con HG y en las P se observó un aumento de las concentraciones plasmáticas de endotelina y GMPc. Las pacientes con HG mostraron una eliminación urinaria disminuida de noradrenalina e incrementada de adrenalina, así como una mayor concentración plasmática de nitritos que su grupo control. En las pacientes con P no se observaron diferencias estadísticamente significativas en la eliminación urinaria de catecolaminas ni en la concentración de nitritos en relación con sus controles. Conclusiones: Existen diferencias relevantes en el patrón de síntesis de mediadores vasoactivos en la HG y la P. Estas diferencias condicionarían una perfusión tisular disminuida en la preeclampsia y podrían contribuir a la génesis de las alteraciones renales de este proceso


Background and objetive: The gestational hypertension -HG- and preeclampsia -P- are hypertensive diseases whose pathogenic mechanism has not been determined yet. The aim of this work is to define some patterns of vasoactive factors release that allow to explain the origin of the differences between both entities. Design: Prospective case-control study. Material and methods: Two groups of target patients were consecutively selected, GH (n = 21) and P patients (n = 21). Every patient was matched with a pregnant of similar age and week of pregnancy. Two control groups were obtained, one respect to the GH and another one respect to the P group. A biochemistry, blood cell count, coagulation and quantification of vasoactive factors endothelin, nitrites and GMPc were performed in every woman. Results of GH and P groups were compared with their respective control group with the paired Student’s t Test. Results: Both systolic and diastolic arterial pressures were higher in hypertensive pregnants (GH and P) than in their respective controls. Moreover, blood endothelin and GMPc were higher in GH and P. GH pregnants showed decreased norepinephrine and increased epinephrine urinary excretion, as well as an increased plasma nitrites concentration than control group. P patients did not show statistically significant differences in catecholamines urinary excretion nor in plasma nitrites concentration respect their control group. Conclusion: There are relevant differences in the synthesis patterns of vasoactive factors between gestational hypertension and preeclampsia. These differences could account for a decreased tissue perfusion in preecalmpsia and could also contribute to the genesis of the renal dysfunction of this entity


Assuntos
Feminino , Gravidez , Humanos , Pré-Eclâmpsia/fisiopatologia , Hipertensão/fisiopatologia , Estudos de Casos e Controles , Norepinefrina/urina , Epinefrina/urina , Endotelinas/análise , Nitritos/análise , Catecolaminas/urina
19.
Arch. bronconeumol. (Ed. impr.) ; 42(3): 113-119, mar. 2006. ilus, tab
Artigo em Es | IBECS | ID: ibc-046185

RESUMO

Objetivo: El estrés oxidativo forma parte esencial de la cadena de acontecimientos que conducen al estado inflamatorio de la vía aérea tras la agresión bacteriana. El objetivo del presente trabajo ha sido investigar si el análisis del condensado del vapor exhalado (CER) de pacientes con infección pulmonar grave refleja las alteraciones del estado oxidativo de la interfase aérea. Pacientes y métodos: Se ha estudiado a un total de 48 pacientes divididos en 4 grupos: sujetos sin enfermedad respiratoria (n = 14), pacientes con neumonía multilobular (n = 13), con enfermedad pulmonar obstructiva crónica sobreinfectados (n = 14) y con neumonía grave ventilados mecánicamente (n = 7). Se obtuvo una muestra de CER en las primeras 72 h tras el ingreso y se determinó la concentración de nitrito, nitrato, 8-isoprostano y mieloperoxidasa (MPO). Resultados: Se apreciaron variaciones significativas de la concentración de nitrito, 8-isoprostano y MPO en los pacientes respecto del grupo control, pero no entre los diferentes grupos de pacientes. La concentración de MPO se relacionó con las concentraciones de 8-isoprostano y nitrato normalizadas para el valor de nitrito. Conclusiones: El análisis de la concentración de 8-isoprostano y MPO en el CER permite apreciar el estrés oxidativo en la interfase aérea de los pacientes con infección pulmonar grave


Objective: Oxidative stress is an intrinsic part of the chain of events leading to inflammation of the airways caused by bacterial infection. The aim of this study was to determine whether analysis of exhaled breath condensate from patients with severe lung infections reveals changes in the redox state at the airway surface. Patients and methods: The study included a total of 48 subjects divided into 4 groups: individuals without respiratory disease (n=14), patients with multilobar pneumonia (n=13), patients who had chronic obstructive pulmonary disease with superinfection (n=14), and mechanically ventilated patients with severe pneumonia (n=7). A sample of exhaled breath condensate was obtained within the first 72 hours of hospital admission and the concentrations of nitrite, nitrate, 8-isoprostane, and myeloperoxidase (MPO) were determined. Results: Significant differences in the concentrations of nitrite, 8-isoprostane, and MPO were observed between patients and individuals without respiratory disease but no differences were found between the 3 patient groups. The concentration of MPO was correlated with the concentrations of 8-isoprostane and nitrate, which were normalized to the nitrite concentration. Conclusions: Analysis of the concentrations of 8-isoprostane and MPO in exhaled breath condensate allows assessment of oxidative stress in the airways of patients with severe lung infections


Assuntos
Humanos , Estresse Oxidativo , Infecções Respiratórias/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Estudos de Casos e Controles , Pneumonia Bacteriana/fisiopatologia , Peroxidase/análise , Espécies Reativas de Nitrogênio/análise , Espécies Reativas de Oxigênio/análise , Isoprostanos/análise , Nitritos/análise , Nitratos/análise , Testes Respiratórios/métodos
20.
J. physiol. biochem ; 61(4): 517-526, oct.-dic. 2005. ilus
Artigo em En | IBECS | ID: ibc-045369

RESUMO

Nitric oxide (NO) can stimulate dendritic cells to a more activated state. However,nitric oxide and peroxynitrites production by dendritic cells has been usuallyassociated with pathological situations such as autoimmunity or inflammatory diseases.This study was designed to determine if dendritic cells obtained from healthyvolunteers produce nitric oxide and peroxynitrites, which results in protein nitration.The expression of arginase II, but not arginase I, isoform was detected in monocytesand dendritic cells. There was higher inducible nitric oxide synthase (iNOS) proteinexpression and lower arginase activity both in immature and mature dendritic cells,compared to monocytes. This caused nitric oxide production, and maturation of dendriticcells which provoked a significative increase of nitrites and nitrates comparedto immature dendritic cells. There was also peroxynitrites synthesis during monocytedifferentiation as shown by the nitration of proteins. Immunoblot revealed a patternof nitrated proteins in cell extracts obtained from monocytes and dendritic cells,however there were bands that appeared only in human dendritic cells, in particularan intense 90 kDa band. Nitric oxide production and nitrotyrosine formation couldaffect the antigen presentation and modify the immune response


Assuntos
Humanos , Células Dendríticas , Óxido Nítrico , Inflamação/fisiopatologia , Autoimunidade/fisiologia , Doenças Autoimunes/fisiopatologia , Arginase , Células Dendríticas/fisiologia , Nitratos/isolamento & purificação , Nitritos/isolamento & purificação , Ácido Peroxinitroso/farmacocinética , Óxido Nítrico/fisiologia
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