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1.
Langmuir ; 36(5): 1156-1164, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-31995383

RESUMO

When a nonthermal plasma and a liquid form part of the same circuit, the liquid may function as a cathode, in which case electrons are emitted from the liquid into the gas to sustain the plasma. As opposed to solid electrodes, the mechanism of this emission has not been established for a liquid, even though various theories have attempted to explain it via chemical processes in the liquid phase. In this work, we tested the effects of the interfacial chemistry on electron emission from water, including the role of pH as well as the hydroxyl radical, the hydrogen atom, the solvated electron, and the presolvated electron; it was found that none of these species are critical to sustain the plasma. We propose an emission mechanism where electrons, generated from ionized water molecules in the uppermost monolayers of solution, are emitted into the plasma directly from the conduction band of the water.

2.
Behav Brain Res ; 372: 112070, 2019 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-31276701

RESUMO

Cocaine exposure disrupts the maternal behavior of lactating rats, yet it is less known whether it alters the affective changes that accompany motherhood. As the long-term action of cocaine on anxiety varies according to the developmental stage of the individuals, this study aimed to compare the effect of a chronic treatment with cocaine to adult and adolescent non-pregnant females on their anxiety-like behavior and basal brain metabolic activity during lactation. Thus, adult and adolescent virgin rats were exposed to cocaine (0.0 or 15.0 mg/kg ip) during 10 days and were mated four days later. Anxiety behavior was evaluated on postpartum days 3-4 in the elevated plus maze test, and the basal brain glucose metabolism was determined on postpartum days 7-9 by means of [18F] fluorodeoxyglucose positron emission tomography. Cocaine treatment during adulthood increased the anxiety-like behavior of lactating females whereas its administration during adolescence decreased it. Also, the basal glucose metabolism of the medial prefrontal cortex differed between lactating females treated with cocaine during adulthood and adolescence. These differential effects of cocaine, according to the age at which the drug was administered, support the idea that the adolescent and adult brains have a distinct susceptibility to this drug, which leads to divergent long-term changes in the neural circuits that regulate anxiety during lactation.


Assuntos
Fatores Etários , Ansiedade/metabolismo , Cocaína/farmacologia , Animais , Transtornos de Ansiedade/metabolismo , Encéfalo/metabolismo , Cocaína/metabolismo , Transtornos Relacionados ao Uso de Cocaína/metabolismo , Inibidores da Captação de Dopamina/farmacologia , Feminino , Glucose/metabolismo , Lactação/efeitos dos fármacos , Comportamento Materno/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Período Pós-Parto/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Gravidez , Ratos
3.
Behav Pharmacol ; 30(5): 396-404, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30379648

RESUMO

Sexual behaviour is highly motivated and female rats begin to express it during adolescence. The circuitries implicated in the control of motivated behaviours continue to mature during adolescence and seem more sensitive to the effects of psychostimulants such as cocaine. However, a putative differential effect of this drug on the sexual behaviour of females according to age has not yet been studied. Therefore, we compared the motivational value of a male and the expression of sexual behaviour of late-adolescent and adult female rats after chronic treatment with a vehicle or 15.0 mg/kg cocaine. The strong incentive value of a male rat, in a male versus female preference test, for adolescent and adult female rats, was not affected by cocaine. During sexual interaction, adolescents were as sexually receptive as were adults; however, they expressed more runaways and social investigation. Cocaine treatment did not modify the expression of sexual behaviour in either group, but increased social investigation in adolescent rats. These results indicate that late-adolescent pro-oestrus females are highly sexually motivated and might express behaviours typical of this life period during sexual interaction. Moreover, although chronic cocaine treatment seemed to affect more adolescents, it did not alter the sexual motivation or behaviour of females.


Assuntos
Cocaína/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Fatores Etários , Animais , Cocaína/metabolismo , Comportamento Exploratório/efeitos dos fármacos , Feminino , Masculino , Motivação/efeitos dos fármacos , Ratos , Comportamento Social
4.
Rev. Fac. Med. (Guatemala) ; 1(25 Segunda Época): 36-41, Jun - Dic 2018.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1127681

RESUMO

Introducción: La 1,25-dihidroxivitamina D3 es la forma activa de la vitamina D, una vitamina lipídica que ahora ya se ha determinado presenta funciones de hormona, tanto calcémicas como no calcémicas. Su producción puede ser endógena gracias a la exposición solar, representando hasta el 90% de valores plasmáticos, o exógena por ingesta en la dieta en forma de vitamina D2 (ergocalciferol).(1) Objetivos: Determinar los niveles de 25-hidroxivitamina D3 en donadores de sangre entre 20-54 años del HGSJDD, así como, evaluar asociación de niveles insuficientes o deficientes con: sexo del donador, lugar de origen, lugar de residencia, edad (años), exposición solar (horas/día), IMC (kg/m2), foto tipo (Fitzpatrick), uso de bloqueador solar (sí/no/ocasional), enfermedades concomitantes y medicamentos de uso habitual. Metodología: Medir los niveles de vitamina D en la sangre de donadores voluntarios. Resultados: La prevalencia de niveles suficientes de vitamina D fue de 33 % de los donadores. Conclusión: Únicamente existe asociación entre el foto tipo Fitzpatrick II con deficiencia o insuficiencia de vitamina D. Palabras Clave: Calcitriol, Deficiencia, Insuficiencia, Suficiencia, foto tipo Fitzpatrick


Introduction: 1,25-dihydroxyvitamin D3 is the active form of vitamin D, a fat-soluble vitamin that has hormone actions, related to calcium homeostasis and other mechanisms. Vitamin D´s synthesis can be endogenous due to solar exposure, making up to 90%. Vitamin D or ingested from diet as the form of vitamin D2 (ergocalciferol). (1) Objectives: To measure levels of Vitamin D in blood from voluntary donors, ages 20-54 y. o, in a general hospital. Results: Prevalence of sufficient levels was 33%. Conclusions: Prevalence of sufficient levels of vitamin D was 33.33%. There is also a relationship between phototype Fitzpatrick II and deficiency or insufficient levels of vitamin D. Key words: Calcitriol, Deficiency, Insufficiency, Sufficiency, Fitzpatrick II photo type

5.
J Vis Exp ; (131)2018 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-29443040

RESUMO

The total internal reflection absorption spectroscopy (TIRAS) method presented in this article uses an inexpensive diode laser to detect solvated electrons produced by a low-temperature plasma in contact with an aqueous solution. Solvated electrons are powerful reducing agents, and it has been postulated that they play an important role in the interfacial chemistry between a gaseous plasma or discharge and a conductive liquid. However, due to the high local concentrations of reactive species at the interface, they have a short average lifetime (~1 µs), which makes them extremely difficult to detect. The TIRAS technique uses a unique total internal reflection geometry combined with amplitude-modulated lock-in amplification to distinguish solvated electrons' absorbance signal from other spurious noise sources. This enables the in situ detection of short-lived intermediates in the interfacial region, as opposed to the bulk measurement of stable products in the solution. This approach is especially attractive for the field of plasma electrochemistry, where much of the important chemistry is driven by short-lived free radicals. This experimental method has been used to analyze the reduction of nitrite (NO2-(aq)), nitrate (NO3-(aq)), hydrogen peroxide (H2O2(aq)), and dissolved carbon dioxide (CO2(aq)) by plasma-solvated electrons and deduce effective rate constants. Limitations of the method may arise in the presence of unintended parallel reactions, such as air contamination in the plasma, and absorbance measurements may also be hindered by the precipitation of reduced electrochemical products. Overall, the TIRAS method can be a powerful tool for studying the plasma-liquid interface, but its effectiveness depends on the particular system and reaction chemistry under study.


Assuntos
Elétrons , Análise Espectral/métodos
6.
Rev. Fac. Med. (Guatemala) ; 1(21 Segunda Época): 30-36, jul - dic 2016.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-969493

RESUMO

Objetivo: Determinar la relación entre el IMC materno obtenido durante el embarazo y el peso y longitud del recién nacido. Metodología: Estudio descriptivo de cohorte, prospectivo ­ retrospectivo, en donde se revisaron 106 expedientes clínicos de pacientes que tuvieron control prenatal y parto en el Centro de Salud Bárbara en San Juan Sacatepéquez entre enero de 2012 y diciembre 2014. Se procesaron y tabularon los datos en Microsoft Excel. Se utilizó la prueba estadística Chi cuadrado para relacionar las variables. Resultados: Se demostró la dependencia entre el IMC materno con el peso y talla del recién nacido, en donde p resultó: < 0.00001, y < 0.000036 respectivamente. CONCLUSIONES: Las embarazadas con IMC normal al momento del parto, tuvieron una mayor proporción de recién nacidos con pesos y tallas adecuadas para la edad gestacional. La mayor proporción de recién nacidos pequeños y grandes para edad gestacional fueron de las pacientes subnutridas y sobre nutridas respectivamente


Objective: The main purposes of the study were to determine the relationship between maternal BMI obtained during pregnancy and the weight and length of the newborn. Methods: Prospective ­ retrospective, descriptive cohort study, where 106 medical records of patients who had prenatal care and childbirth at Barbara Health Center between January 2012 and December2014. Data was processed and tabulated in Microsoft Excel. The Chi square statistical test was used to relate variables. Results: There was a direct relationship between maternal BMI with the weight and length of the newborns, where p value was <0.00001, and<0.000036 respectively. Conclusions: Pregnant women with normal BMI at birth had a higher proportion of infants with weight and size appropriate for gestational age. The largest proportion of small and large newborns for gestational age was observed in undernourished patients and obese ones respectively

7.
Guatemala; INCAP; sept. 2014. 38 p. ilus, tab, graf.
Monografia em Espanhol | Repositório RHS | ID: biblio-981957

RESUMO

La siguiente compilación ilustra aspectos importantes de la historia del Instituto de Nutrición de Centro América y Panamá, INCAP, en el importante campo de la formación y desarrollo de los Recursos Humanos en Alimentación y Nutrición. En este aniversario del INCAP, excelentes profesionales que han trabajado en este campo en el Instituto, dan testimonio de los inicios, desarrollo, logros, evolución y trascendencia del quehacer del INCAP y su contribución para que los países de Centroamérica, Panamá, República Dominicana, América Latina y otros países del mundo, cuenten con recursos humanos formados para enfrentar científica y técnicamente el quehacer en la construcción de la Seguridad Alimentaria y Nutricional de las poblaciones. Ahora, más que nunca, los países miembros del INCAP enfrentan enormes retos para el cumplimiento del Derecho Humano a la alimentación. En esta empresa, sus aliados naturales son aquellos científicos y técnicos que, egresados de Programas desarrollados o generados con apoyo del Instituto, aportan a los y las pobladoras de los países su compromiso, calidad, humanidad y espíritu de excelencia. Sirvan estos apuntes para reconocer la labor de los Directores y todos los profesionales, técnicos y operarios, que con su talento y esfuerzo, han hecho y hacen del INCAP un espacio para la Ciencia y para la búsqueda de la verdad, esencia del espíritu de investigación; y para el arte de enseñar y educar en función de la vida de los seres humanos; así como para construir y recrear esta noble y valiosa Institución. (AU)


Assuntos
Humanos , Desenvolvimento de Pessoal , Capacitação de Recursos Humanos em Saúde , Mão de Obra em Saúde/organização & administração , Educação Alimentar e Nutricional , América Latina
8.
Salud Publica Mex ; 53 Suppl 3: S303-11, 2011.
Artigo em Espanhol | MEDLINE | ID: mdl-22344375

RESUMO

To describe the regional master plan of nutrition to address maternal and child malnutrition in a 5- year period developed by the Nutrition Technical Group. The Nutrition Technical Group developed a situation analysis describing the main nutrition problems, policies and programs in Mesoamerica. The situation analysis and a literature review about effective interventions to address malnutrition were conducted to develop a nutrition master plan. The Nutrition Technical Group held various meetings to develop, discuss and validate the master plan. Theory of change identified problems and barriers, the actions to be developed, the changes and impacts expected. A package of interventions is proposed to reduce undernutrition and micronutrient deficiencies useful under different epidemiological contexts. The nutrition master plan provides a guideline of best practices that can be used for evidence-informed decision making and the development of national policies and programs to reduce malnutrition.


Assuntos
Transtornos da Nutrição Infantil/prevenção & controle , Bem-Estar da Criança , Promoção da Saúde/organização & administração , Transtornos da Nutrição do Lactente/prevenção & controle , Desnutrição/prevenção & controle , Bem-Estar Materno , Complicações na Gravidez/prevenção & controle , Saúde Pública , América Central/epidemiologia , Transtornos da Nutrição Infantil/epidemiologia , Pré-Escolar , Países em Desenvolvimento , Suplementos Nutricionais , Feminino , Alimentos Fortificados , Política de Saúde , Humanos , Lactente , Transtornos da Nutrição do Lactente/epidemiologia , Recém-Nascido , Cooperação Internacional , Desnutrição/epidemiologia , México/epidemiologia , Micronutrientes , Necessidades Nutricionais , Apoio Nutricional , Formulação de Políticas , Guias de Prática Clínica como Assunto/normas , Gravidez , Complicações na Gravidez/epidemiologia
9.
Salud pública Méx ; 53(supl.3): s303-s311, 2011. ilus
Artigo em Espanhol | LILACS | ID: lil-625710

RESUMO

Describir un plan maestro para el desarrollo de planes nacionales para prevenir la desnutrición materno-infantil en Mesoamérica en un plazo de cinco años. Para ello se elaboró un análisis sobre los principales problemas, políticas y programas de nutrición en Mesoamérica. A partir del análisis y de la revisión de la literatura sobre las mejores prácticas en el combate a la desnutrición, el Grupo Técnico de Nutrición desarrolló, discutió y validó el plan durante varias reuniones presenciales. Se desarrolló la teoría de cambio que identifica los problemas y barreras, las acciones propuestas, los cambios e impactos esperados. Se propone la implementación de paquetes de intervenciones para reducir la desnutrición y deficiencia de micronutrientes de utilidad para diversos contextos epidemiológicos. El plan maestro de nutrición constituye un insumo que puede facilitar la elaboración de propuestas de programas y políticas dirigidos a reducir la desnutrición y promover la toma de decisiones basadas en evidencia.


To describe the regional master plan of nutrition to address maternal and child malnutrition in a 5- year period developed by the Nutrition Technical Group. The Nutrition Technical Group developed a situation analysis describing the main nutrition problems, policies and programs in Mesoamerica. The situation analysis and a literature review about effective interventions to address malnutrition were conducted to develop a nutrition master plan. The Nutrition Technical Group held various meetings to develop, discuss and validate the master plan. Theory of change identified problems and barriers, the actions to be developed, the changes and impacts expected. A package of interventions is proposed to reduce undernutrition and micronutrient deficiencies useful under different epidemiological contexts. The nutrition master plan provides a guideline of best practices that can be used for evidence-informed decision making and the development of national policies and programs to reduce malnutrition.


Assuntos
Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Bem-Estar da Criança , Transtornos da Nutrição Infantil/prevenção & controle , Promoção da Saúde/organização & administração , Transtornos da Nutrição do Lactente/prevenção & controle , Bem-Estar Materno , Desnutrição/prevenção & controle , Saúde Pública , Complicações na Gravidez/prevenção & controle , América Central/epidemiologia , Transtornos da Nutrição Infantil/epidemiologia , Países em Desenvolvimento , Suplementos Nutricionais , Alimentos Fortificados , Política de Saúde , Cooperação Internacional , Transtornos da Nutrição do Lactente/epidemiologia , Micronutrientes , Desnutrição/epidemiologia , México/epidemiologia , Necessidades Nutricionais , Apoio Nutricional , Formulação de Políticas , Guias de Prática Clínica como Assunto/normas , Complicações na Gravidez/epidemiologia
10.
Curr Opin Pediatr ; 19(4): 405-10, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17630603

RESUMO

PURPOSE OF REVIEW: The paper reviews the most recent US and non-US literature on media interventions designed to decrease sexual risk behaviors among adolescents and young adults, and their impact on youth's sexual knowledge, attitudes and behaviors. This review focuses on interventions using mass media, computers and the Internet. RECENT FINDINGS: Recent research suggests that a variety of media sources and strategies that include mass media communication, computer-assisted instruction and the Internet can be used effectively for increasing knowledge and changing attitudes on sexual health issues and for promoting responsible sexual behaviors among young people. Media interventions seem to be more effective to achieve these goals when an array of channels are used simultaneously and when these efforts are sustained over time. SUMMARY: Policymakers, school systems, parents and health providers need to be aware that media can be used effectively to decrease sexual risk behaviors in adolescents and young adults, especially when complemented with interpersonal strategies. These interventions can be implemented in different settings such as clinics, schools and colleges and even at a national level through large media campaigns.


Assuntos
Promoção da Saúde , Meios de Comunicação de Massa , Comportamento Sexual , Adolescente , Comportamento do Adolescente , Feminino , Humanos , Assunção de Riscos , Gravação de Videoteipe
12.
Environ Health Perspect ; 110(1): 109-14, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11781172

RESUMO

In this study, we aimed to establish whether domestic use of wood fuel is associated with reduced birth weight, independent of key maternal, social, and economic confounding factors. We studied 1,717 women and newborn children in rural and urban communities in rural Guatemala. We identified subjects through home births reported by traditional birth attendants in six rural districts (n = 572) and all public hospital births in Quetzaltenango city during the study period (n = 1,145). All were seen within 72 hr of delivery, and data were collected on the type of household fuel used, fire type, and socioeconomic and other confounding factors. Smoking among women in the study community was negligible. Children born to mothers habitually cooking on open fires (n = 861) had the lowest mean birth weight of 2,819 g [95% confidence interval (CI), 2,790-2,848]; those using a chimney stove (n = 490) had an intermediate mean of 2,863 g (95% CI, 2,824-2,902); and those using the cleanest fuels (electricity or gas, n = 365) had the highest mean of 2,948 g (95% CI, 2,898-2,998) (p< 0.0001). The percentage of low birth weights (< 500 g) in these three groups was 19.9% (open fire), 16.8% (chimney stove), and 16.0% (electricity/gas), (trend (p = 0.08). Confounding factors were strongly associated with fuel type, but after adjustment wood users still had a birth weight 63 g lower (p = 0.05; 95% CI, 0.4-126). This is the first report of an association between biofuel use and reduced birth weight in a human population. Although there is potential for residual confounding despite adjustment, the better-documented evidence on passive smoking and a feasible mechanism through carbon monoxide exposure suggest this association may be real. Because two-thirds of households in developing countries still rely on biofuels and women of childbearing age perform most cooking tasks, the attributable risk arising from this association, if confirmed, could be substantial.


Assuntos
Poluição do Ar em Ambientes Fechados/efeitos adversos , Culinária , Países em Desenvolvimento , Exposição Ambiental , Recém-Nascido de Baixo Peso , Fumaça/efeitos adversos , Adolescente , Adulto , Fatores de Confusão Epidemiológicos , Feminino , Fogo , Guatemala/epidemiologia , Humanos , Incidência , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Gravidez , Medição de Risco , População Rural , Madeira
17.
Rev. estomatol. Hered ; 10(1/2): 17-23, 2000. ilus, tab
Artigo em Espanhol | LILACS, LIPECS | ID: lil-289669

RESUMO

Se analizan las características clínicas radiológicas e histológicas de cinco casos de quiste óseo solitario (QOS). El rango de edad de los pacientes fue entre 12 a 20 años. Todas las lesiones fueron hallazgos radiográficos asintomáticos ubicados en la región molar-premolar mandibular. Cuatro lesiones presentaron forma de cono con la punta dirigida hacia la parte distal de la mandíbula. Además de la imagen radiográfica típica en cuatro casos se obervó erosión del hueso cortical basal. El control radiográfico en tres casos mostró reparación ósea completa después de seis meses, inflamación crónica y trabéculas óseas maduras e inmaduras. En un caso se observó un foco de lesión fibroósea benigna y médula ósea roja. Este estudio demuestra que el QOS puede corresponder a: a) lesión inflamatoria hemorrágica, b) lesión intraósea benigna y c) médula ósea roja.


Assuntos
Cistos Ósseos/patologia , Cistos Ósseos , Cistos Ósseos/terapia
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