RESUMO
Soil infertility is a global problem, amendments such as organic fertilizers and mineral fertilizers are used to improve crop yields. However, these fertilizers contain heavy metals as well as essential mineral elements. The objective of the study was to determine the effect of organic and inorganic fertilizer on the accumulation and health risk of heavy metals in tubers. The plants were cultivated at an altitude of 3970â¯m using four treatments (poultry manure, alpaca manure, island guano and inorganic fertilizer) and a control group. Soil contamination levels and the degree of metal accumulation in the tubers were also determined. As a result, it was found that the use of inorganic fertilizer and poultry manure increased the values of Cu and Zn in soils, exceeding the recommended standards. The accumulation of heavy metals in potato tubers did not exceed the maximum recommended limits with the exception of Pb, which exceeded the limit allowed by the FAO/WHO (0.1â¯mgâ¯kg-1). Poultry manure contributed to the highest accumulation of Zn, Cu and Pb in tubers with 11.62±1.30, 3.48±0.20 and 0.12 ±0.02â¯mgâ¯kg-1 respectively. The transfer of metals from the soil to the tubers was less than 1. Individual and total non-carcinogenic risk values were less than 1, indicating a safe level of consumption for children and adults. The cancer risk was found to be within an acceptable range. However, poultry manure and inorganic fertilizer treatments had the highest total cancer risk values in both age groups, suggesting a long-term carcinogenic risk.
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Heavy metal contamination of soil and agricultural products is an environmental problem, has an adverse effect on the quality of food crops, and is a danger to food security and public health. The concentration of arsenic (As), cadmium (Cd), lead (Pb), iron (Fe) and zinc (Zn) in surface soils and edible hypocotyls tissues of two ecotypes of Lepidium meyenii Walpers (maca) was evaluated in three districts of the Junín province, Peru. In addition, the risk to human health due to exposure to heavy metals from maca consumption was evaluated. Soil samples and maca hypocotyls were collected in areas influenced by mining and metallurgical activity. The mean concentration of Cd (0.32 ± 0.23 mg/kg) and Pb (0.20 ± 0.12 mg/kg) in maca samples exceeded the values established by the Food and Agriculture Organization and the World Health Organization. The bioconcentration factor was less than 1. The estimated daily intake of each metal was below the oral reference dose. The hazard quotient and hazard index were less than 1, it is unlikely to cause non-cancer adverse health outcome. The cancer risk for As and Cd was higher than the tolerable limit (1 × 10-6) in children and adults. In the district of Ondores, the cancer risk for As in children was higher than the acceptable limit (1 × 10-4). Residents of the Ondores district would be more exposed to As and Cd from consumption of maca hypocotyls. It is very important to carry out continuous monitoring of other toxic metals in different ecotypes of maca (red, black, yellow, purple, creamy white, pink) in order to evaluate the variation in the accumulation of heavy metals and the level of toxicity of each metal between ecotypes.
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Radiation-induced degradation of chlorobenzene was conducted at 0.1, 0.4, 0.5, 0.7, and 1.0 mmol/dm3 concentrations in aerated environment and at 1.0 mmol/dm3 in oxygen-free and N2O-saturated solutions. The results demonstrated that the elimination of chloride is important when the solution is oxygen free, because the [Formula: see text] attacks at the ipso position of the chloro group produces hydrochloric acid. The degradation was affected to a large extent by the concentration and to a lesser extent by the presence or absence of oxygen in the solutions which were irradiated. Thereby, the degradation occurred faster in the solutions with air and without oxygen and more slowly in the saturated solution with N2O. Some by-products were identified using an HPLC-UV-mass system. In addition, it was found that there is a linear correlation between the ln C/C0 and the dose, indicating that the radiolytic degradation followed pseudo-first-order reaction kinetics. The radiolytic oxidation was followed by the chemical oxygen demand (COD) test. The COD decreases when the solute concentration increases. The COD results were for a 0.47 mmol/dm3 of 5.94 mg O2 dm-3 kGy-1 and for 0.09 mmol/dm3 of 7.45 mg O2 dm-3 kGy-1.
Assuntos
Clorobenzenos , Purificação da Água , Análise da Demanda Biológica de Oxigênio , Cinética , Oxirredução , Soluções , ÁguaRESUMO
Evaluate the effect of a synbiotic on salivary viscosity and buffer capacity. Materials and Methods: A follow-up one-week study was performed on 24 healthy volunteers in San Luis Potosí, Mexico, during July 2017. Volunteers must have had active tooth decay at the moment of study. All 24 patients were given a Lactiv® probiotic package, advising not to modify usual oral hygiene practices, and were followed up during 6 days. Primary output variable was salivary viscosity while the secondary was salivary buffer capacity. Salivary viscosity was assessed by using an Ostwald Pipette and buffer capacity with bromocresol purple. Results: A total of 8 male patients (33.3%) and 16 females (66.6%) patients were included, with an average age of 10.92 years. All the volunteers completed the study. Comparisons between pre- and post-treatment showed a decrease in salivary viscosity, while buffer capacity was showed to increase. Conclusion: The use of a synbiotic during a short period of time lowered the viscosity of saliva and increased salivary buffer capacity.
Evaluar el efecto de un sinbiótico sobre la viscosidad salival y la capacidad de tampón de la saliva. Materiales and Métodos: Se realizó un estudio de seguimiento de una semana en 24 voluntarios sanos en San Luis Potosí, México, durante julio de 2017. Los voluntarios cursaban caries dental activa en el momento del estudio. Los 24 pacientes recibieron un paquete de probióticos Lactiv®, fueron aconsejados a no modificar las prácticas habituales de higiene oral, y fueron seguidos durante 6 días. La variable primaria fue la viscosidad salival mientras que la secundaria fue la capacidad tampón. La viscosidad salival se evaluó usando una pipeta Ostwald y capacidad tampón con bromocresol púrpura. Resultados: Se incluyeron un total de 8 pacientes varones (33,3%) y 16 mujeres (66,6%), con una edad promedio de 10,92 años. Todos los voluntarios completaron el estudio. Las comparaciones entre el pretratamiento y el postratamiento mostraron una disminución de la viscosidad salival, mientras que se demostró que la capacidad del tampón aumentó. Conclusión: El uso de un sinbiótico durante un corto período de tiempo mostró un efecto sobre la disminución de la viscosidad y el aumento de la capacidad del tampón salival.
Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Saliva/efeitos dos fármacos , Probióticos/administração & dosagem , Simbióticos , Viscosidade , Resultado do Tratamento , Cárie Dentária , Ensaios Clínicos Controlados não Aleatórios como Assunto , MéxicoRESUMO
En los últimos años, el tenis ha crecido en popularidad, provocando que la competitividad se haya incrementado considerablemente en todos los grupos de edad. Los jugadores de tenis, para ser competitivos y alcanzar el éxito, requieren de un alto nivel de desarrollo en cuatro habilidades fundamentales: táctica, técnica, física y psicológica. A la hora de diseñar programas de entrenamiento para los tenistas, es importante tener en cuenta los requerimiento físicos y fisiológicos de los jugadores, ya que pueden variar según el nivel del jugador, el estilo de juego, el sexo o la superficie de la pista, entre otros. Estas habilidades fundamentales y requerimientos se deben trabajar en edades tempranas para lograr el éxito en edades adultas, por lo tanto, el objetivo de la presente revisión sistemática fue estudiar las características de los programas de entrenamiento que se han llevado a cabo en jóvenes tenistas para mejorar su rendimiento. Se realizó una estrategia de búsqueda electrónica utilizando las bases de datos PubMed, SPORTDiscus y los términos tennis, performance, adolescent, male, female, training e intervention. Veintitrés artículos fueron revisados y solo 7 cumplieron los criterios de inclusión. El programa de entrenamiento pliométrico es el más utilizado para mejorar el rendimiento de los jóvenes tenistas, siendo un programa de corta duración, barato y de fácil cumplimentación para entrenadores y preparadores físicos de tenis. Esta revisión sistemática podría contribuir al diseño de futuros programas de entrenamiento para mejorar el rendimiento de jóvenes tenistas(AU)
In recent years, tennis has grown in popularity, causing competitiveness to have increased significantly in all age groups. Tennis players, in order to be competitive and achieve success, require a high level of development in four fundamental skills: tactical, technical, physical and psychological. When designing training programs for tennis players, it is important to take into account the physical and physiological requirements of the players, as they may vary according to player level, the play style, sex or track surface, among others. These fundamental skills and requirements must be worked at an early age to achieve success in adult ages, therefore, the systematic review objective was to study the training programs characteristics in young tennis players for improve their performance. An electronic search strategy was performed using PubMed, SPORTDiscus and the terms tennis, performance, adolescent, male, female, training and intervention. Twenty-three articles were reviewed and only seven met the inclusion criteria. The plyometric training program is the most used to performance improve of young tennis players, being a short, inexpensive and easy rogram for tennis trainers. This systematic review could contribute to future design for training programs to performance improve of young tennis players(AU)
Assuntos
Humanos , Adolescente , Exercício Físico/psicologia , Tênis/educação , Desempenho Atlético/normasRESUMO
Vitamin loss during irradiation has been claimed as a critical area in food irradiation technology, especially that of thiamine (B1), which has been considered as the most sensitive to radiation. Although it has been suggested that no vitamin deficiency could result from consuming irradiated food, a long debate on the loss of vitamins and other nutrients during food irradiation has been maintained by the lack of experimental studies monitoring decomposition rates at different concentrations and doses. Since thiamine, riboflavin, and pyridoxine are labile vitamins, this study has focused on their radiolytic decomposition in dilute aqueous solutions in the presence of air. The decomposition process was followed by HPLC and UV-spectroscopy. The results obtained in aqueous solutions showed a dependence of the decomposition as a nonlinear function of the dose. Of these three compounds, the decomposition was higher for thiamine than for riboflavin and even less in pyridoxine.
La pérdida de vitaminas durante procesos de irradiación ha sido considerada como un área crítica en la tecnología de irradiación de alimentos, especialmente la tiamina (B1), que ha sido considerada como la más sensible a la radiación ionizante. La deficiencia de vitaminas en humanos no es producida por el consumo de alimentos irradiados, sin embargo, existen debates sobre la pérdida de vitaminas y otros nutrientes provocada por la irradiación de alimentos, esta discusión sigue latente debido a que hay pocos estudios experimentales de la descomposición de vitaminas a diferentes dosis y concentraciones. Esta investigación se centró en el estudio de la descomposición radiolítica de tiamina, riboflavina y piridoxina en soluciones acuosas y en presencia de aire. El proceso de descomposición fue seguido por cromatografía líquida con detección UV. Los resultados obtenidos en soluciones acuosas mostraron una dependencia no lineal entre la descomposición en función de la dosis. De estos tres compuestos, la descomposición fue mayor en tiamina que en riboflavina y menor en la piridoxina.
A perda de vitaminas durante processos de irradiação tem sido considerada uma área crítica na tecnologia de irradiação de alimentos, especialmente no caso da tiamina (B1), que tem sido considerada como a mais sensível à radiação ionizante. Embora a deficiência de vitaminas em seres humanos não seja produzida pelo consumo de alimentos irradiados, longos debates sobre as perdas de vitaminas e outros nutrientes causadas pela irradiação de alimentos tem sido mantidos devido aos estudos experimentais limitados monitorando a proporção da decomposição em diferentes concentrações de vitaminas e doses de radiação aplicadas. Considerando que a tiamina, riboflavina e piridoxina são vitaminas instáveis, o presente estudo focalizou a decomposição radiolítica dessas vitaminas em soluções aquosas diluídas e na presença de ar. O processo de decomposição foi analizado por cromatografia líquida com detecção UV. Os resultados obtidos em soluções aquosas mostraram uma dependência da decomposição como função não linear da dose. Destes três compostos, a descomposição foi mais alta para tiamina que na riboflavina e menor para piridoxina.
RESUMO
In some Sonoran Desert Cactaceae the primary root has a determinate root growth: the cells of the root apical meristem undergo only a few cell division cycles and then differentiate. The determinate growth of primary roots in Cactaceae was found in plants cultivated under various growth conditions, and could not be reverted by any treatment tested. The mechanisms involved in root meristem maintenance and determinate root growth in plants remain poorly understood. In this study, we have shown that roots regenerated from the callus of two Cactaceae species, Stenocereus gummosus and Ferocactus peninsulae, have a determinate growth pattern, similar to that of the primary root. To demonstrate this, a protocol for root regeneration from callus was established. The determinate growth pattern of roots regenerated from callus suggests that the program of root development is very stable in these species. These findings will permit future analysis of the role of certain Cactaceae genes in the determinate pattern of root growth via the regeneration of transgenic roots from transformed calli.
Assuntos
Cactaceae/crescimento & desenvolvimento , Clima Desértico , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/fisiologia , Regeneração , Cactaceae/citologia , Cotilédone/fisiologia , Meios de Cultura , Hipocótilo/fisiologia , México , Raízes de Plantas/citologia , Plântula/fisiologia , Técnicas de Cultura de TecidosRESUMO
La anestesia combinada espinal-peridural es una técnica de anestesia regional que une las ventajas del bloqueo espinal con las del bloqueo peridural. Se ha usado ampliamente en cirugías abdominales, ginecológicas y analgésia obstétrica. Esta técnica anetésica al igual que otras, no escapa de presentar riesgos y complicaciones. En este caso clínico se presenta una paciente de 56 años de edad ASA I, programado para hernioplastia umbilical e inguinal derecha, a quién se le realizó una anestésia combinada espinal-peridural usando un equipo Portex 16/26 y la técnica de aguja a través de aguja, sin complicaciones. Apróximadamente 20 horas después, presenta un bloqueo espinal alto durante la administración de la tercera dosis de analgesia peridural intermitente. El objetivo de este caso clínico es dar a conocer esta complicación poco frecuente de la anestesia combinada espinal-peridural y señalar las posibles causas de la misma. Por lo cual, hicimos un análisis del caso y un razonamiento bibliográfico que nos llevó a concluir que la causa de la anestesia espinal total fue el paso de mezcla analgésica del espacio peridural al subcranoideo a través del agujero espinal Whitacre de 26 Gauge. Asimismo señalaremos recomendaciones a seguir para la realización de la técnica combinada y para el uso del catéter peridural durante la analgesia posoperatoria
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Masculino , Humanos , Feminino , Anestesia Epidural , Anestesia Obstétrica , Venezuela , AnestesiologiaRESUMO
En este estudio se evaluaron los conocimientos, posibles acciones y actitudes de los alumnos del 3§, 4§ y 5§ año de educación secundaria del Centro Educativo Particular "Miguel Angel" frente a la ocurrencia de un mismo. La población total estuvo constituída por 500 alumnos: eligiéndose una muestra representativa de 120 alumnos de ambos sexos; cuyas edades fluctuaban entre 13 a 19 años. Se tomó una prueba de evaluación inicial, a las tres secciones; la prueba estuvo constituída por 27 preguntas que involucran temas como: Conocimientos generales, medidas preventivas, problemas de conducta, salud ambiental con posterioridad a los desastres, tipo de atención médica y atención de primeros auxilios. En esta evaluación se evidenció escasos conocimientos: el promedio global obtenido fue de 10.3. En base a los resultados obtenidos se elaboró un programa educativo desarrollado en los meses de agosto a noviembre con un total de 24 horas dictadas. Finalizando la intervención educativa se tomó la prueba de evaluación final: utilizando la prueba de evaluación inicial; observándose un incremento altamente significativo con un promedio global de 15.5. Se recalca la importancia de esta educación que deberá ser periódica y continua.