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1.
Environ Monit Assess ; 192(1): 5, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31797222

RESUMO

Lake Cajititlán is a shallow body of water located in an endorheic basin in western Mexico. This lake receives excess fertilizer runoff from agriculture and approximately 2.3 Hm3 per year of poorly treated wastewater from three municipal treatment plants. Thirteen water quality parameters were monitored at five sampling points within the lake over 9 years. The objective of this work was to characterize the spatial and temporal variations of the water quality and to identify the sources of data variability in order to assess the influence and the impact of different natural and anthropogenic processes. One-way ANOVA tests, principal component analysis (PCA), cluster analysis (CA), and discriminant analysis (DA) were implemented. The one-way ANOVA showed that biochemical oxygen demand and pH present statistically significant spatial variations and that alkalinity, total chloride, conductivity, chemical oxygen demand, total hardness, ammonia, pH, total dissolved solids, and temperature present statistically significant temporal variations. PCA results explained both natural and anthropogenic processes and their relationship with water quality data. The CA results suggested there is no significant spatial variation in the water quality of the lake because of lake mixing caused by wind. The most significant parameters for spatial variations were pH, NO3-, and NO2-, consistent with the configuration of point and nonpoint sources that affect the lake's water quality. The temporal DA results suggested that conductivity, hardness, NO2-, pH, and temperature were the most significant parameters to discriminate between seasons. The temporal behavior of these parameters was associated with the transport pathways of seasonal contaminants.


Assuntos
Monitoramento Ambiental , Lagos/química , Análise Multivariada , Qualidade da Água , Análise por Conglomerados , Análise Discriminante , Monitoramento Ambiental/métodos , México , Análise de Componente Principal , Estações do Ano , Poluentes Químicos da Água/análise
2.
Nutr. hosp ; 36(3): 517-525, mayo-jun. 2019. tab, graf
Artigo em Inglês | IBECS | ID: ibc-184547

RESUMO

Introduction: children with cerebral palsy (CP) have multiple risk factors for low bone mineral density or osteoporosis. Objective: to explore the association between bone mineral density (BMD) and biochemical and hormonal indicators of bone metabolism in children with quadriplegic cerebral palsy (CP). Methods: a cross-sectional analytical study included 59 participants from six to 18 years of age with quadriplegic CP. Serum concentrations of calcium, phosphorus, 25OHD metabolite, parathyroid hormone (PTH), alkaline phosphatase, and thyroid hormones were determined using standardized methods. The BMD measurement was obtained from the lumbar spine expressed in g/cm2 and Z-score. Unpaired Student's t-test, Chi-square test, odds ratio and Pearson's correlation were performed. Results: participants with CP and malnutrition had lower serum concentrations of calcium, phosphorus and alkaline phosphatase. Those who had low BMD showed lower serum concentrations of calcium, phosphorus and alkaline phosphatase. Most participants with low and normal BMD had vitamin D deficiency (27.1% and 10%) and insufficiency (35.4% and 30%), respectively. There was a significant correlation between BMD and serum concentrations of calcium, phosphorus, alkaline phosphatase, vitamin D and thyroid-stimulating hormone (TSH). There were no differences in the biochemical and hormonal indicators by level of gross motor function, use of anticonvulsants and oral versus enteral feeding method. Conclusion: malnutrition and alteration of vitamin D nutritional status were associated with low BMD and alterations of biochemical indicators of bone metabolism in pediatric patients with quadriplegic CP. The relationship between BMD and biochemical indicators of bone metabolism in children with quadriplegic CP was also demonstrated


Introducción: los niños con parálisis cerebral (PC) presentan múltiples factores de riesgo de densidad mineral ósea baja u osteoporosis. Objetivo: explorar la asociación entre la baja densidad mineral ósea (DMO) e indicadores bioquímicos y hormonales del metabolismo óseo en niños con PC cuadripléjica. Métodos: un estudio transversal analítico incluyó a 59 participantes de entre seis y 18 años de edad con PC cuadripléjica. Las concentraciones séricas de calcio, fósforo, metabolito 25OHD, hormona paratiroidea (PTH), fosfatasa alcalina y hormonas tiroideas se determinaron utilizando métodos estandarizados. La medición de DMO se obtuvo de la columna lumbar expresada en g/cm2 y puntaje Z. Se realizaron pruebas t de Student no pareada, Chi-cuadrado, razón de momios y correlación de Pearson. Resultados: los participantes con PC y desnutrición tenían concentraciones séricas más bajas de calcio, fósforo y fosfatasa alcalina. Los participantes con DMO baja tuvieron menor concentración sérica de calcio, fósforo y fosfatasa alcalina. Los participantes con DMO baja y normal tenían deficiencia de vitamina D (27.1% y 10%) e insuficiencia (35.4% y 30%), respectivamente. Hubo una correlación significativa entre DMO y las concentraciones séricas de calcio, fósforo, fosfatasa alcalina, vitamina D y hormona estimulante de la tiroides. Conclusión: la desnutrición y la alteración del estado nutricio de la vitamina D se asociaron con DMO baja y alteraciones de los indicadores bioquímicos del metabolismo óseo. Se demostró una asociación entre DMO e indicadores bioquímicos y hormonales del metabolismo óseo en niños con PC cuadripléjica


Assuntos
Humanos , Criança , Adolescente , Densidade Óssea , Paralisia Cerebral/dietoterapia , Paralisia Cerebral/diagnóstico , Quadriplegia/complicações , Estado Nutricional , Vitamina D/sangue , Cálcio/sangue , Quadriplegia/dietoterapia , Quadriplegia/diagnóstico , Estudos Transversais , Osso e Ossos/metabolismo , Fosfatase Alcalina/análise , Fosfatase Alcalina/sangue , Dióxido de Carbono/sangue
3.
Environ Monit Assess ; 191(6): 396, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31123902

RESUMO

Lake Cajititlán is an endorheic tropical lake located in the state of Jalisco, Mexico, which has suffered the consequences of high levels of eutrophication. This study assessed the presence of heavy metals and metalloids in Lake Cajititlán to ascertain possible risks to its aquatic biota and the environment. Eleven monitoring sites were selected throughout the lake; from each site, one sample was taken from the sediments and another from the sediment-water interface by using an Ekman dredger and a Van Dorn bottle, respectively. The measured metals in each sample were As, Cd, Cr, Hg, Pb, Zn, Cu, Ni, Fe, Mn, and Al. The results showed the following sequence of heavy metal concentrations Al > Fe > Mn > Zn > Cu > Cr, wherein Al had the highest average concentration and Cr had the lowest. As, Cd, Hg, and Pb were practically undetectable. Because the predominant rock in the lake basin is volcanic tuff and the soil is vertisol, the high quantities of Al and Fe suggest the weathering of the basin's minerals. The analyses of the sediment-water samples contained small amounts of dissolved Al, Fe, and Mn. According to the Håkanson equations with Hg, Cd, As, Cu, Pb, Cr, and Zn, the calculations of the contamination degree and ecological risk revealed that the presence of metals and metalloids does not present a potential risk to the aquatic biota; nonetheless, the water is not suitable for local human consumption due to an unrelated factor associated with nutrient and bacteriological contamination. The results show that heavy metals in the sediments were dispersed throughout the lake mostly because of the weathering of minerals from the local basin and not because of the punctual discharges of the pollutants from the municipal wastewater treatment plants (WWTPs). However, to ensure that the small amounts of dissolved metals (Al, Fe, and Mn) do not affect the aquatic biota, the fish species and phytoplankton need to be internally analyzed.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Metais Pesados/análise , Poluentes Químicos da Água/análise , Animais , Ecologia , Eutrofização , Peixes , Humanos , Lagos/análise , México , Medição de Risco/métodos , Solo/química , Águas Residuárias/análise , Água/análise
4.
Nutr Hosp ; 36(3): 517-525, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30958686

RESUMO

Introduction: Introduction: children with cerebral palsy (CP) have multiple risk factors for low bone mineral density or osteoporosis. Objective: to explore the association between bone mineral density (BMD) and biochemical and hormonal indicators of bone metabolism in children with quadriplegic cerebral palsy (CP). Methods: a cross-sectional analytical study included 59 participants from six to 18 years of age with quadriplegic CP. Serum concentrations of calcium, phosphorus, 25OHD metabolite, parathyroid hormone (PTH), alkaline phosphatase, and thyroid hormones were determined using standardized methods. The BMD measurement was obtained from the lumbar spine expressed in g/cm2 and Z-score. Unpaired Student's t-test, Chi-square test, odds ratio and Pearson's correlation were performed. Results: participants with CP and malnutrition had lower serum concentrations of calcium, phosphorus and alkaline phosphatase. Those who had low BMD showed lower serum concentrations of calcium, phosphorus and alkaline phosphatase. Most participants with low and normal BMD had vitamin D deficiency (27.1% and 10%) and insufficiency (35.4% and 30%), respectively. There was a significant correlation between BMD and serum concentrations of calcium, phosphorus, alkaline phosphatase, vitamin D and thyroid-stimulating hormone (TSH). There were no differences in the biochemical and hormonal indicators by level of gross motor function, use of anticonvulsants and oral versus enteral feeding method. Conclusion: malnutrition and alteration of vitamin D nutritional status were associated with low BMD and alterations of biochemical indicators of bone metabolism in pediatric patients with quadriplegic CP. The relationship between BMD and biochemical indicators of bone metabolism in children with quadriplegic CP was also demonstrated.


Assuntos
Densidade Óssea , Paralisia Cerebral/metabolismo , Hormônios/metabolismo , Quadriplegia/metabolismo , Adolescente , Cálcio na Dieta , Paralisia Cerebral/complicações , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Desnutrição/metabolismo , Estado Nutricional , Quadriplegia/etiologia , Hormônios Tireóideos/sangue , Deficiência de Vitamina D/complicações
5.
Environ Monit Assess ; 191(2): 92, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30671653

RESUMO

Lake Cajititlán is a shallow water body located in an endorheic basin in western Mexico at 1551 m a.s.l. The surface area is 1744 ha, maximum storage volume achieved is 70.89 Hm3, and maximum depth is 5.4 m at its maximum capacity. The lake has experienced significant changes in its level because of drought conditions in recent years. Because the lake has shallow features and is settled in a closed basin with rapid population growth, the lake water has suffered severe anthropogenic contamination causing damages in its intrinsic esthetic, social, environmental, and economic values.


Assuntos
Lagos/química , Qualidade da Água , Clorofila/análise , Cianobactérias/crescimento & desenvolvimento , Monitoramento Ambiental , México , Oxigênio/análise , Fotossíntese , Poluição da Água/análise
6.
Arch Osteoporos ; 13(1): 17, 2018 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-29504042

RESUMO

This study demonstrated the relationship of low bone mineral density (BMD) with the degree of motor impairment, method of feeding, anthropometric indicators, and malnutrition in children with quadriplegic cerebral palsy (CP). The control of these factors could optimize adequate bone mineralization, avoid the risk of osteoporosis, and would improve the quality of life. PURPOSE: The purpose of the study is to explore the relationship between low BMD and nutritional status in children with quadriplegic CP. METHODOLOGY: A cross-sectional analytical study included 59 participants aged 6 to 18 years with quadriplegic CP. Weight and height were obtained with alternative measurements, and weight/age, height/age, and BMI/age indexes were estimated. The BMD measurement obtained from the lumbar spine was expressed in grams per square centimeter and Z score (Z). Unpaired Student's t tests, chi-square tests, odds ratios, Pearson's correlations, and linear regressions were performed. RESULTS: The mean of BMD Z score was lower in adolescents than in school-aged children (p = 0.002). Patients with low BMD were at the most affected levels of the Gross Motor Function Classification System (GMFCS). Participants at level V of the GMFCS were more likely to have low BMD than levels III and IV [odds ratio (OR) = 5.8 (confidence interval [CI] 95% 1.4, 24.8), p = 0.010]. There was a higher probability of low BMD in tube-feeding patients [OR = 8.6 (CI 95% 1.0, 73.4), p = 0.023]. The probability of low BMD was higher in malnourished children with weight/age and BMI indices [OR = 11.4 (1.3, 94), p = 0.009] and [OR = 9.4 (CI 95% 1.1, 79.7), p = 0.017], respectively. CONCLUSION: There was a significant relationship between low BMD, degree of motor impairment, method of feeding, and malnutrition. Optimizing these factors could reduce the risk of osteopenia and osteoporosis and attain a significant improvement of quality of life in children with quadriplegic CP.


Assuntos
Densidade Óssea , Paralisia Cerebral , Estado Nutricional , Osteoporose , Qualidade de Vida , Adolescente , Antropometria/métodos , Peso Corporal , Paralisia Cerebral/complicações , Paralisia Cerebral/metabolismo , Paralisia Cerebral/fisiopatologia , Paralisia Cerebral/psicologia , Criança , Estudos Transversais , Comportamento Alimentar , Feminino , Humanos , Masculino , México , Osteoporose/diagnóstico , Osteoporose/etiologia , Osteoporose/prevenção & controle , Fatores de Risco
7.
Environ Monit Assess ; 187(3): 134, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25701474

RESUMO

The Aguamilpa Dam is part of the reservoir cascade system formed by four reservoirs in the middle and lower part of the Santiago River. For decades, this system has received urban and industrial wastewater from the metropolitan area of Guadalajara and the runoff of agricultural fields located in the river basin. The present study was carried out to obtain a preliminary assessment on the concentration distribution of heavy metals (Al, Ba, Cd, Cr, Cu, Fe, Hg, Mg, Ni, Pb, and Zn) in surface sediments of the Aguamilpa reservoir collected from 10 sampling stations. The metal concentrations (mg kg(-1)) in the sampling stations ranged as follows: Al, 27,600-7760; Ba, 190.0-15.9; Cd, 0.27-0.02; Cr, 18.30-0.22; Cu, 60.80-0.79; Fe, 15,900-4740; Hg, 0.04-0.01; Mg, 7590-8.05; Ni, 189.00-0.24; Pb, 13.6-1.64; and Zn, 51.8-14.8. Significant spatial variation in concentrations was observed for Al, Fe, and Pb. Sediment pollution was evaluated using the enrichment factor, the geo-accumulation index, the pollution load index, and sediment quality guidelines. Based on geo-accumulation and pollution load indexes, Aguamilpa sediments were found, in some sampling stations, as unpolluted to moderately polluted with Ni, Cd, Cu, and Mg. Enrichment factors showed that Cd is highly related to agricultural activities that take place in the surrounding areas of the Aguamilpa reservoir. Despite these results, none of the heavy metals evaluated exceeded international concentrations limits, indicating that the Aguamilpa reservoir surface sediments are not contaminated.


Assuntos
Sedimentos Geológicos/química , Metais Pesados/análise , Centrais Elétricas , Rios/química , Poluentes Químicos da Água/análise , Agricultura , Monitoramento Ambiental/métodos , Metais/análise , México
8.
Interciencia ; 32(2): 100-107, feb. 2007. mapas, graf
Artigo em Espanhol | LILACS | ID: lil-493031

RESUMO

Como consecuencia de la disminución en los caudales de ingreso y de la contaminación, así como de la pérdida de volumen debido a la extracción, desde hace varios años el Lago de Chapala sufre un proceso de entrofización cultural debida al exceso de nutrientes, lo cual se manifiesta en el crecimiento de vegetación acuática en la desembocadura del río Lerma y en el mismo lago. La aplicación de técnicas no convencionales basadas en un modelo de celdas para obtener un balance de masa para el fósforo (P) y fosfatos (PO4-³) demostraron que la principal fuente de este nutriente en el lago es el río Lerma, debido a que este recibe descargas municipales, agrícolas e industríales a lo largo de la cuenca con un tratamiento limitado. Este trabajo propone un método riguroso de evaluación de la acumulación de P y PO4-³ en el Lago de Chapala. Se demuestra que el lago perdió su capacidad de remover P total desde el año de 1983 y PO4-³ a partir del periodo 1977-1978. Igualmente se determinó que la cantidad promedio de PO4-³ en el lago representan el 67,6 por ciento del fósforo total, lo cual mantiene en altos niveles la disponibilidad biológica de este nutriente en la columna de agua.


Assuntos
Bacias , Ecossistema , Eutrofização , Lagos , Fósforo , Rios , Balanço Hídrico , Hidrologia , México
9.
Interciencia ; 31(5): 345-350, mayo. 2006. tab, graf
Artigo em Inglês | LILACS | ID: lil-449518

RESUMO

En este trabajo se propone un modelo de simulación estocástica para determinar los límites de los estados tróficos en lagos y embalses cálidos tropicales en Latinoamérica, basada en una correlación estadística y en técnicas de MonteCarlo. El modelo se desarrolló en el lenguaje de simulación discreto GPSS y fue calibrado con un conjunto de variables de estado de 27 lagos y presas de América Latina monitoreados por el Centro Panamericano de Ingeniería Sanitaria (CEPIS). A fin de garantizar una mejor estabilidad en el comportamiento probabilístico de la variable dependiente a partir de las distribuciones muestrales de las variables predictivas, se generaron 10000 cuerpos de agua de los diferentes estados tróficos y se produjo un índice de estado trófico basado en la concentración del fósforo total. Sobre la base de los resultados obtenidos se concluye que la metodología es apropiada para estimar los límites entre los estados tróficos de lagos y embalses y produce resultados similares a los obtenidos por otras metodologías


Assuntos
Barragens , Lagos , Níveis Tróficos , México
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