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1.
GM Crops Food ; 15(1): 85-104, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38506577

RESUMO

We estimate producer and consumer surplus changes due to a possible GM maize import ban in Chile, which produces only non-GM grains for internal use. Without foreign non-GM sources, the ban's effect on domestic maize prices would be so significant as to induce Chile to switch from net exporter to net importer of animal products. Fixed factor owners in farm production would benefit significantly, although non-GM maize imports would moderate gains. Total social welfare measures would decline considerably, requiring large offsetting noneconomic benefits for a ban's political viability. Without non-GM imports, internal maize prices would likely eliminate domestic animal product industries; with possible imports, industries and final consumers would suffer, but much less. Currently, the country is a net importer of grain and a net exporter of pork and poultry, and so most welfare losses on the demand side of the market for maize would be in terms of the economic rents generated by the pork and poultry sectors. International competition would protect final consumers to the extent that animal product imports based on GM feed were permitted.


Assuntos
Animais Domésticos , Zea mays , Animais , Chile , Zea mays/genética , Grão Comestível , Fazendas
2.
Environ Health ; 21(1): 68, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35836250

RESUMO

BACKGROUND: Inorganic arsenic (iAs) is a ubiquitous metalloid and drinking water contaminant. Prenatal exposure is associated with birth outcomes across multiple studies. During metabolism, iAs is sequentially methylated to mono- and di-methylated arsenical species (MMAs and DMAs) to facilitate whole body clearance. Inefficient methylation (e.g., higher urinary % MMAs) is associated with increased risk of certain iAs-associated diseases. One-carbon metabolism factors influence iAs methylation, modifying toxicity in adults, and warrant further study during the prenatal period. The objective of this study was to evaluate folate, vitamin B12, and homocysteine as modifiers of the relationship between biomarkers of iAs methylation efficiency and birth outcomes. METHODS: Data from the Biomarkers of Exposure to ARsenic (BEAR) pregnancy cohort (2011-2012)  with maternal urine and cord serum arsenic biomarkers and maternal serum folate, vitamin B12, and homocysteine concentrations were utilized. One-carbon metabolism factors were dichotomized using clinical cutoffs and median splits. Multivariable linear regression models were fit to evaluate associations between each biomarker and birth outcome overall and within levels of one-carbon metabolism factors. Likelihood ratio tests of full and reduced models were used to test the significance of statistical interactions on the additive scale (α = 0.10). RESULTS: Among urinary biomarkers, % U-MMAs was most strongly associated with birth weight (ß = - 23.09, 95% CI: - 44.54, - 1.64). Larger, more negative mean differences in birth weight were observed among infants born to women who were B12 deficient (ß = - 28.69, 95% CI: - 53.97, - 3.42) or experiencing hyperhomocysteinemia (ß = - 63.29, 95% CI: - 154.77, 28.19). Generally, mean differences in birth weight were attenuated among infants born to mothers with higher serum concentrations of folate and vitamin B12 (or lower serum concentrations of homocysteine). Effect modification by vitamin B12 and homocysteine was significant on the additive scale for some associations. Results for gestational age were less compelling, with an approximate one-week mean difference associated with C-tAs (ß = 0.87, 95% CI: 0, 1.74), but not meaningful otherwise. CONCLUSIONS: Tissue distributions of iAs and its metabolites (e.g., % MMAs) may vary according to serum concentrations of folate, vitamin B12 and homocysteine during pregnancy. This represents a potential mechanism through which maternal diet may modify the harms of prenatal exposure to iAs.


Assuntos
Arsênio , Arsenicais , Efeitos Tardios da Exposição Pré-Natal , Adulto , Arsênio/toxicidade , Biomarcadores/metabolismo , Peso ao Nascer , Carbono , Feminino , Ácido Fólico , Homocisteína , Humanos , Metilação , Gravidez , Vitamina B 12
3.
Genet Mol Biol ; 44(3): e20210020, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34617949

RESUMO

Nitrates in drinking water has been associated to adverse health effects, including changes in glucose and lipid levels, thyroid hormone imbalance and adverse reproductive effects. We analyzed metabolic and thyroid hormone alterations and genotoxic damage in women with chronic exposure to nitrates in drinking water. The concentration of nitrates in drinking water was quantified and according to this parameter, participants were divided into three exposure scenarios. Blood and urine samples were collected from 420 women living in Durango, Mexico and biomarkers were determined. We found nitrates concentrations in drinking water above the permissible limit (>50 mg/L), and an increase in the percentage of methemoglobin (p=0.0001), nitrite in blood plasma and urine (p=0.0001), glucose (p=0.0001), total cholesterol (p=0.001), LDL (p=0.001) and triglycerides (p=0.0001). We also found alterations in TSH (p=0.01), fT3 (p=0.0003), T4T (p=0.01) and fT4 (p=0.0004) hormones. Frequency of subclinical hypothyroidism was 8.33%; differences in FOXE1 (rs965513, rs1867277) genotypes distribution were found and both polymorphisms were associated with a decrease in TSH. A high percentage of micronucleus in binucleate lymphocyte cells was found (35%, p=0.0001). In conclusion, the chronic exposure to nitrates in water for human consumption caused metabolic and hormonal alterations and genotoxic damage in women.

4.
J Clin Lipidol ; 15(1): 124-133, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33422452

RESUMO

BACKGROUND: Familial hypercholesterolemia (FH) remains underdiagnosed and undertreated. OBJECTIVE: Report the results of the first years (2017-2019) of the Mexican FH registry. METHODS: There are 60 investigators, representing 28 federal states, participating in the registry. The variables included are in accordance with the European Atherosclerosis Society (EAS) FH recommendations. RESULTS: To date, 709 patients have been registered, only 336 patients with complete data fields are presented. The mean age is 50 (36-62) years and the average time since diagnosis is 4 (IQR: 2-16) years. Genetic testing is recorded in 26.9%. Tendon xanthomas are present in 43.2%. The prevalence of type 2 diabetes is 11.3% and that of premature CAD is 9.8%. Index cases, male gender, hypertension and smoking were associated with premature CAD. The median lipoprotein (a) level is 30.5 (IQR 10.8-80.7) mg/dl. Statins and co-administration with ezetimibe were recorded in 88.1% and 35.7% respectively. A combined treatment target (50% reduction in LDL-C and an LDL-C <100 mg/dl) was achieved by 13.7%. Associated factors were index case (OR 3.6, 95%CI 1.69-8.73, P = .002), combination therapy (OR 2.4, 95%CI 1.23-4.90, P = .011), type 2 diabetes (OR 2.8, 95%CI 1.03-7.59, P = .036) and age (OR 1.023, 95%CI 1.01-1.05, P = .033). CONCLUSION: The results confirm late diagnosis, a lower than expected prevalence and risk of ASCVD, a higher than expected prevalence of type 2 diabetes and undertreatment, with relatively few patients reaching goals. Recommendations include, the use of combination lipid lowering therapy, control of comorbid conditions and more frequent genetic testing in the future.


Assuntos
Hiperlipoproteinemia Tipo II , Adulto , Humanos , Pessoa de Meia-Idade
5.
Vet Sci ; 7(2)2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32375384

RESUMO

The Region Lagunera, a region in northeast Mexico, is undergoing significant problems with the quality of its groundwater, which exceeds the permissible limits of contaminants and/or heavy metals stipulated in Mexican legislation. The present study evaluated chronic toxicity in male goats exposed to arsenic via one ex situ Group 1 (n = 5) and one in situ female goats Group 3 (n = 10). The treatment in Group 1 was carried out in the La Laguna experimental field of the Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias (INIFAP), located in Matamoros, Coahuila, Mexico. Sodium arsenite (2 mg/kg) was orally administered for 84 days to five male Creole goats, aged between four and five years old and weighing between 60 and 70 kg, in order to determine its effect on urine toxicity, libido, and physiological condition, an untreated group (n = 5) was included (Group 2). The experiment in group 3 was conducted on ten female Creole goats, aged between four and six years old and weighing between 40 and 49 kg, in both the contaminated sampling area in the rural community of El Venado and the control sampling area in the rural community of Nuevo Reynosa (Group 4 (n = 5)), in which the arsenic levels were measured in the urine of the exposed goats, as was their physiological condition. Significant differences (p < 0.01) between the groups were found in both the arsenic concentration in the urine and the physiological condition observed in both experimental groups.

6.
Rheumatology (Oxford) ; 59(10): 3092-3098, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32442272

RESUMO

OBJECTIVE: SSc is a systemic fibrotic disease affecting skin, numerous internal organs and the microvasculature. The molecular pathogenesis of SSc tissue fibrosis has not been fully elucidated, although TGF-ß1 plays a crucial role. The Hic-5 protein encoded by the TGF-ß1-inducible HIC-5 gene participates in numerous TGF-ß-mediated pathways, however, the role of Hic-5 in SSc fibrosis has not been investigated. The aim of this study was to examine HIC-5 involvement in SSc tissue fibrosis. METHODS: Affected skin from three patients with diffuse SSc and dermal fibroblasts cultured from affected and non-affected SSc skin were examined for HIC-5 and COL1A1 gene expression. Real-time PCR, IF microscopy, western blotting and small interfering RNA-mediated HIC-5 were performed. RESULTS: HIC-5 and COL1A1 transcripts and Hic-5, type 1 collagen (COL1) and α-smooth muscle actin (α-SMA) protein levels were increased in clinically affected SSc skin compared with normal skin and in cultured dermal fibroblasts from affected SSc skin compared with non-affected skin fibroblasts from the same patients. HIC-5 knockdown caused a marked reduction of COL1 production in SSc dermal fibroblasts. CONCLUSION: HIC-5 expression is increased in affected SSc skin compared with skin from normal individuals. Affected SSc skin fibroblasts display increased HIC-5 and COL1A1 expression compared with non-affected skin fibroblasts from the same patients. Hic-5 protein was significantly increased in cultured SSc dermal fibroblasts. HIC-5 mRNA knockdown in SSc fibroblasts caused >50% reduction of COL1 production. Although these are preliminary results owing to the small number of skin samples studied, they indicate that Hic-5 plays a role in the profibrotic activation of SSc dermal fibroblasts and may represent a novel molecular target for antifibrotic therapy in SSc.


Assuntos
Colágeno Tipo I/metabolismo , Fibroblastos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas com Domínio LIM/metabolismo , Escleroderma Sistêmico/metabolismo , Actinas/metabolismo , Colágeno/metabolismo , Colágeno Tipo I/genética , Cadeia alfa 1 do Colágeno Tipo I , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas com Domínio LIM/efeitos dos fármacos , Proteínas com Domínio LIM/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Escleroderma Sistêmico/genética , Pele/metabolismo , Fator de Crescimento Transformador beta/farmacologia
7.
Heliyon ; 6(12): e05729, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33385079

RESUMO

Blastocystis is a parasite commonly found in the gut of humans and animals; there are 22 known subtypes (STs). STs 1-9 and 12 have been found in humans. This parasite has a faecal-oral route of transmission; its high infection prevalence in developing countries is due to poor hygiene practices, exposure to infected animals, and intake of contaminated water or food. Its pathogenicity has not been established, because it has been found in symptomatic and asymptomatic patients. The goal of this study was to analyze the frequency of Blastocystis and its subtypes (1, 2, 3, 4, 5, and 7), and assess the relationship between these subtypes and abdominal pain and distension. 202 university students participated in this study. A questionnaire was applied to assess the gastrointestinal symptoms, and subsequently the students were asked to provide faecal samples. The presence of parasites was determined by optical microscopy. Blastocystis-positive samples had their DNA extracted and end-point PCR was performed to corroborate the presence of Blastocystis and determine its subtypes. Among the samples, 47.03% were positive according to PCR analysis. The most prevalent subtypes were ST3 (29.79%), ST4 (16.84%), and ST1 (14.89%). We found a relationship between ST1 and abdominal pain (OR = 0.196; CI = 0.0533-0.7318; p = 0.015), and between ST4 and abdominal distension (OR = 0.2928; CI = 0.1017-0.8429; p = 0.023). However, the presence of this parasite and the probable relationship with gastrointestinal symptoms suggest the need to determine its role within intestinal microbiota in order to confirm whether its eradication is really necessary or not.

8.
Arch Cardiol Mex ; 89(4): 301-307, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31834315

RESUMO

Introduction: Radial access is the gold standard for ST-elevation myocardial infarction; nevertheless, there is scarce information in Mexico. Objectives: The objectives of this study were to describe the differences in radiation exposure, intervention time, fluoroscopy time, complications and temporal trends, and risk factors among radial and femoral access for coronary procedures. Materials and Methods: A total of 493 patients underwent coronary interventions by femoral or radial access. Sociodemographic and procedural data were recorded. A logistic regression model to determine risk factors for complications was performed. Results: The population included 346 men and 147 women, with a median age of 63 years, 159 underwent radial and 334 femoral approaches. Complications occurred in 18 patients (3.6%), 11 in radial and 7 in femoral access, with a higher trend in the first 5 months (n = 14). Vasospasm was the most common (n = 9) complication. Median fluoroscopy time was 12 min for radial and 9 min for femoral groups, with a total radiation dose of 2282 µGm2 and 2848 µGm2, respectively. Temporal trends showed that complications occurred most frequently during the first 6 months of the study. The main predictors for complications were intervention time and one-vessel disease. Conclusions: Radial access had higher frequency of complications than femoral approach and they were more common during the first 6 months. The main risk factor was intervention time longer than 60 min.


Introducción: El abordaje radial es el de elección para infarto de miocardio con elevación del segmento ST, sin embargo se desconoce información en México. Objetivos: Describir las diferencias en exposición a radiación, tiempo de intervención, tiempo de fluoroscopía, complicaciones y sus variaciones temporales, además de los factores de riesgo entre el abordaje radial y el femoral para procedimientos coronarios. Método: Se incluyeron 493 pacientes que fueron sometidos a estudio angiográfico o intervenciones coronarias por abordaje radial o femoral. Se recabaron datos sociodemográficos, antecedentes y variables del procedimiento. Se realizó un modelo de regresión logística para determinar los factores asociados a complicaciones. Resultados: Se incluyeron 346 hombres y 147 mujeres, con mediana de edad de 63 años. A 159 se les realizó acceso radial y a 334 femoral. Las complicaciones ocurrieron en 18 pacientes (3.65%): 11 en radial y 7 en femoral, teniendo mayor incidencia en los primeros 5 meses (n = 14) y siendo el vasoespasmo el más común (n = 9). La mediana de tiempo de fluoroscopía fue de 12 minutos para el radial y de 9 minutos para el femoral, con una dosis total de radiación de 2,282 µGm2 y 2,848 µGm2, respectivamente. Las tendencias temporales indicaron que las complicaciones fueron más frecuentes durante los primeros 6 meses. Los principales predictores fueron el tiempo de intervención y la enfermedad de 1 vaso. Conclusiones: La vía de acceso radial tuvo más complicaciones que la femoral. Se observaron más complicaciones en los primeros 6 meses del estudio. El principal predictor de complicaciones fue el tiempo de intervención mayor a 60 minutos.


Assuntos
Artéria Femoral , Intervenção Coronária Percutânea/métodos , Artéria Radial , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Coronária/métodos , Estudos Transversais , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/efeitos adversos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
9.
Arch. cardiol. Méx ; 89(4): 301-307, Oct.-Dec. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1149087

RESUMO

Abstract Introduction: Radial access is the gold standard for ST-elevation myocardial infarction; nevertheless, there is scarce information in Mexico. Objectives: The objectives of this study were to describe the differences in radiation exposure, intervention time, fluoroscopy time, complications and temporal trends, and risk factors among radial and femoral access for coronary procedures. Materials and Methods: A total of 493 patients underwent coronary interventions by femoral or radial access. Sociodemographic and procedural data were recorded. A logistic regression model to determine risk factors for complications was performed. Results: The population included 346 men and 147 women, with a median age of 63 years, 159 underwent radial and 334 femoral approaches. Complications occurred in 18 patients (3.6%), 11 in radial and 7 in femoral access, with a higher trend in the first 5 months (n = 14). Vasospasm was the most common (n = 9) complication. Median fluoroscopy time was 12 min for radial and 9 min for femoral groups, with a total radiation dose of 2282 µGm2 and 2848 µGm2, respectively. Temporal trends showed that complications occurred most frequently during the first 6 months of the study. The main predictors for complications were intervention time and one-vessel disease. Conclusions: Radial access had higher frequency of complications than femoral approach and they were more common during the first 6 months. The main risk factor was intervention time longer than 60 min.


Resumen Introducción: El abordaje radial es el de elección para infarto de miocardio con elevación del segmento ST, sin embargo se desconoce información en México. Objetivos: Describir las diferencias en exposición a radiación, tiempo de intervención, tiempo de fluoroscopía, complicaciones y sus variaciones temporales, además de los factores de riesgo entre el abordaje radial y el femoral para procedimientos coronarios. Método: Se incluyeron 493 pacientes que fueron sometidos a estudio angiográfico o intervenciones coronarias por abordaje radial o femoral. Se recabaron datos sociodemográficos, antecedentes y variables del procedimiento. Se realizó un modelo de regresión logística para determinar los factores asociados a complicaciones. Resultados: Se incluyeron 346 hombres y 147 mujeres, con mediana de edad de 63 años. A 159 se les realizó acceso radial y a 334 femoral. Las complicaciones ocurrieron en 18 pacientes (3.65%): 11 en radial y 7 en femoral, teniendo mayor incidencia en los primeros 5 meses (n = 14) y siendo el vasoespasmo el más común (n = 9). La mediana de tiempo de fluoroscopía fue de 12 minutos para el radial y de 9 minutos para el femoral, con una dosis total de radiación de 2,282 µGm2 y 2,848 µGm2, respectivamente. Las tendencias temporales indicaron que las complicaciones fueron más frecuentes durante los primeros 6 meses. Los principales predictores fueron el tiempo de intervención y la enfermedad de 1 vaso. Conclusiones: La vía de acceso radial tuvo más complicaciones que la femoral. Se observaron más complicaciones en los primeros 6 meses del estudio. El principal predictor de complicaciones fue el tiempo de intervención mayor a 60 minutos.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem , Artéria Radial , Artéria Femoral , Intervenção Coronária Percutânea/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Fatores de Tempo , Estudos Transversais , Fatores de Risco , Resultado do Tratamento , Angiografia Coronária/métodos , Intervenção Coronária Percutânea/efeitos adversos , México
10.
J Expo Sci Environ Epidemiol ; 29(5): 732, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31171829

RESUMO

A correction to this paper has been published and can be accessed via link at the top of the paper.

11.
J Expo Sci Environ Epidemiol ; 29(5): 718-729, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30728485

RESUMO

Exposure to inorganic arsenic (iAs) remains a global public health problem. Urinary arsenicals are the current gold-standard for estimating both iAs exposure and iAs metabolism. However, the distribution of these arsenicals may differ between the urine and target organs. Instead, plasma arsenicals may better represent internal dose and capture target organ exposure to arsenicals. Drinking water iAs, plasma and urinary arsenicals were quantified in individuals living in the Zimapan and Lagunera regions of Mexico. The relationship between drinking water iAs and plasma arsenicals was examined using both Spearman correlations and multivariable linear regression models. In addition, the distribution of arsenicals in plasma and urine was examined and the association between plasma and urinary arsenicals was assessed using both Spearman correlations and multivariable linear regression models. Levels of iAs in drinking water were significantly associated with plasma arsenicals in unadjusted and adjusted analyses and the strength of these associations was similar to that of drinking water iAs and urinary arsenicals. These results suggest that plasma arsenicals are reliable biomarkers of iAs exposure via drinking water. However, there were notable differences between the profiles of arsenicals in the plasma and the urine. Key differences between the proportions of arsenicals in plasma and urine may indicate that urine and plasma arsenicals reflect different aspects of iAs toxicokinetics, including metabolism and excretion.


Assuntos
Arsenicais/sangue , Exposição Ambiental/análise , Intoxicação por Arsênico , Biomarcadores/metabolismo , Água Potável/análise , Feminino , Humanos , Modelos Lineares , Masculino , México , Toxicocinética
12.
Rev. Fac. Med. UNAM ; 62(1): 33-37, ene.-feb. 2019. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1013223

RESUMO

Resumen La arteria del nodo sinoatrial irriga al marcapasos principal del corazón y su oclusión o lesión puede generar arritmias. Se reportó un infarto de miocardio inferior, el cual presentó oclusión total trombótica proximal de la coronaria derecha, y presentó desde extrasístoles atriales hasta bloqueo atrioventricular. Se describieron las 6 rutas que puede seguir la arteria del nodo sinoatrial y las distintas manifestaciones clínicas que puede tener su oclusión o daño. Se deben realizar estudios de prevalencia para conocer la distribución de esta arteria en la población mexicana, y poder predecir con mayor probabilidad los trastornos del ritmo.


Abstract The sinus node artery irrigates the main pacemaker of the heart and its occlusion or damage can generate arrhythmias. We reported the case of a patient that had an inferior myocardial infarction due to total thrombotic occlusion of the proximal right coronary artery, atrial premature beats and an atrioventricular block. We described the 6 routes that the sinus node artery can follow and the different clinical manifestations that can be observed if occluded. Prevalence studies should be conducted to determine the distribution of this artery in the Mexican population, and to be able to predict rhythm disorders with a higher probability.

13.
Environ Res ; 170: 65-72, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30557693

RESUMO

OBJECTIVES: Lead exposure is associated with children's growth, but this relationship may depend on the presence of susceptibility factors, including genetic variation. Blood lead levels (BLL) differ by ALAD (aminolevulinic acid dehydratase) genotype. We investigated the association between BLL and growth in Mexican first-graders with different ALAD genotypes. METHODS: Children between the ages of 6-8 years (n = 602) attending first grade in schools within the vicinity of a metal foundry in Torreón, Mexico were enrolled into a randomized controlled trial (RCT) testing the efficacy of iron and/or zinc supplementation on blood lead levels (BLL) and cognition. BLL and anthropometry were assessed at baseline (height, height-for-age z-score (HAZ), knee height, head circumference), after 6 (head circumference) and 12 months (height, HAZ, knee height). Children with ALAD1-1 and ALAD1-2/2-2 were compared. The study sample included 538 and 470 participants who had complete data at baseline and follow-up, respectively. Separate multivariable linear regression models adjusted for covariates were used to test the association between BLL at baseline and each anthropometric measure. Covariates included age, sex, hemoglobin, crowding, and maternal education. BLL x ALAD genotype interaction term was tested. RESULTS: Median BLL (10.1 µg/dL) did not differ by ALAD genotype. After covariate adjustment, baseline BLL was inversely associated with baseline height, HAZ, and knee height. The association (ß [95% CI]) between BLL and baseline height (-0.38[-0.68, -0.09]), HAZ (-0.07[-0.12, -0.02]) and knee height (-0.14[-0.25, -0.02]), was somewhat stronger in children with ALAD1-2/2-2 than ALAD1-1 (-0.09[-0.16, -0.02], -0.02[-0.03, -0.004] and -0.04[-0.06, -0.01], respectively). No associations between BLL and growth at 6 or 12 months were detected irrespective of ALAD genotype. CONCLUSIONS: BLL was adversely associated with anthropometric measures among Mexican children. ALAD genotype may be a susceptibility factor for the effects of lead on child growth.


Assuntos
Antropometria , Exposição Ambiental/estatística & dados numéricos , Chumbo , Sintase do Porfobilinogênio/genética , Criança , Genótipo , Humanos , México
14.
Environ Int ; 123: 292-300, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30553202

RESUMO

BACKGROUND: Exposure to inorganic arsenic (iAs) via drinking water is a serious global health threat. Various factors influence susceptibility to iAs-associated health outcomes, including differences in iAs metabolism. Previous studies have shown that obesity is associated with iAs metabolism. It has been hypothesized that this association can be explained by confounding from nutritional factors involved in one-carbon metabolism, such as folate or other B vitamins, whose intake may differ across BMI categories and is known be associated with iAs metabolism. However, no studies have explored whether this association is confounded by nutritional factors. METHODS: We investigated the relationship between body mass index (BMI) and the distribution of urinary arsenic species in a cross-sectional cohort of 1166 adults living in Chihuahua, Mexico from 2008 to 2013. Nutrient intake related to one-carbon metabolism, including folate, vitamin B2, and vitamin B12, was assessed using a food frequency questionnaire developed for Mexican populations. Multivariable linear regression was used to estimate the association between BMI and the distribution of urinary arsenic metabolites. Effect modification by drinking water iAs level and sex was also examined. RESULTS: After adjusting for potential confounders, including age, educational attainment, smoking, alcohol consumption, seafood consumption, water iAs, and sex, BMI was negatively associated with the proportion of urinary inorganic arsenic (%U-iAs) and urinary monomethylated arsenic (%U-MMAs) and positively associated with urinary dimethylated arsenic (%U-DMAs). This relationship was not influenced by additional adjustment for folate, vitamin B2, or vitamin B12 intake. Additionally, there was significant effect modification by both drinking water iAs level and sex. CONCLUSIONS: This study provides further evidence for an association between BMI and arsenic metabolism. However, contrary to previous hypotheses, these results suggest that this association is not confounded by the intake of micronutrients involved in one-carbon metabolism.


Assuntos
Arsênio/urina , Índice de Massa Corporal , Carbono/metabolismo , Nutrientes/metabolismo , Adulto , Arsênio/análise , Estudos de Coortes , Estudos Transversais , Exposição Ambiental , Feminino , Humanos , Masculino , México , Estado Nutricional , Fumar
15.
Environ Sci Technol ; 52(24): 14487-14495, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30457847

RESUMO

Arsenic (As) is a toxic metalloid. Inorganic arsenic (iAs) is a form of As commonly found in drinking water and in some foods. Overwhelming evidence suggests that people chronically exposed to iAs are at risk of developing cancer or cardiovascular, neurological, and metabolic diseases. Although the mechanisms underlying iAs-associated illness remain poorly characterized, a growing body of literature raises the possibility that microRNAs (miRNAs), post-transcriptional gene suppressors, may serve as mediators and/or early indicators of the pathologies associated with iAs exposure. To characterize the circulating miRNA profiles of individuals chronically exposed to iAs, samples of plasma were collected from 109 healthy residents of the city of Zimapán and the Lagunera area in Mexico, the regions with historically high exposures to iAs in drinking water. These plasma samples were analyzed for small RNAs using high-throughput sequencing and for iAs and its methylated metabolites. Associations between plasma levels of arsenic species and miRNAs were evaluated. Six circulating miRNAs (miRs-423-5p, -142-5p -2, -423-5p +1, -320c-1, -320c-2, and -454-5p), two of which have been previously linked to cardiovascular disease and diabetes (miRs-423-5p, -454-5p), were found to be significantly correlated with plasma MAs. No miRNAs were associated with plasma iAs or DMAs after correction for multiple testing. These miRNAs may represent mechanistic links between iAs exposure and disease or serve as markers of disease risks associated with this exposure.


Assuntos
Arsênio , MicroRNA Circulante , Água Potável , MicroRNAs , Humanos , México
16.
Radiol Case Rep ; 13(6): 1212-1215, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30233762

RESUMO

Many factors have been associated with venous thromboembolism. Among them, vitamin B12 deficiency can produce elevated homocysteine levels, which is a risk factor for venous embolism, since the latter interferes with the activation of Va coagulation factor by activation of C protein. We present a case of a patient with metabolic syndrome with apparently unprovoked pulmonary embolism. After careful evaluation, megaloblastic anemia was detected. Even though the patient had biochemistry findings of hemolysis and blood smear did not showed fragmented erythrocytes, which is consistent with pseudo-microangiopathic hemolytic anemia.

17.
J Expo Sci Environ Epidemiol ; 28(5): 505-514, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30068932

RESUMO

The prenatal period represents a critical window of susceptibility to inorganic arsenic (iAs) exposure from contaminated drinking water. Ingested iAs undergoes hepatic methylation generating mono and di-methyl arsenicals (MMAs and DMAs, respectively), a process that facilitates urinary arsenic (As) elimination. Differences in pregnant women's metabolism of As as indicated by greater proportions of MMAs and smaller proportions of  DMAs in urine are a risk factor for adverse birth outcomes. One carbon metabolism (OCM), the nutritionally-regulated pathway essential for supplying methyl groups, plays a role in As metabolism and is understudied during the prenatal period. In this cross-sectional study from the Biomarkers of Exposure to ARsenic (BEAR) pregnancy cohort in Gómez Palacio, Mexico, we assessed the relationships among OCM indicators (e.g. maternal serum B12, folate, and homocysteine (Hcys)), and levels of iAs and its metabolites in maternal urine and in neonatal cord serum. The prevalence of folate sufficiency (folate levels > 9 nmol/L) in the cohort was high 99%, and hyperhomocysteinemia (Hcys levels > 10.4 µmol/L) was low (8%). However, 74% of the women displayed a deficiency in B12 (serum levels < 148 pmol/L). Association analyses identified that infants born to mothers in the lowest tertile of serum folate had significantly higher mean levels of %MMA in cord serum relative to folate replete women. In addition, elevated maternal Hcys was associated with total As in maternal urine and cord serum as well as cord serum %MMAs. The results from this study indicate that maternal OCM status may influence the distribution of As metabolites in cord serum.


Assuntos
Arsênio/urina , Biomarcadores/sangue , Biomarcadores/urina , Exposição Ambiental/análise , Ácido Fólico/sangue , Homocisteína/sangue , Adulto , Estudos de Coortes , Estudos Transversais , Água Potável/efeitos adversos , Exposição Ambiental/efeitos adversos , Feminino , Sangue Fetal/química , Humanos , Recém-Nascido , Masculino , Metilação , México , Gravidez , Gestantes , Análise de Regressão , Vitamina B 12/sangue , Adulto Jovem
18.
Biology (Basel) ; 7(3)2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29949946

RESUMO

Mitochondrial dysfunction is a hallmark of diabetes, but the metabolic alterations during early stages of the disease remain unknown. The ability of liver cells to rearrange their metabolism plays an important role in compensating the energy shortage and may provide cell survival. Moringa oleifera leaves have been studied for its health properties against diabetes, insulin resistance, and non-alcoholic liver disease. We postulated that M. oleifera executes a protective function on mitochondrial functionality in HepG2 treated with high glucose. We evaluated the effect of high glucose treatment on the mitochondrial function of HepG2 cells using a Seahorse extracellular flux analyzer (Agilent, Santa Clara, CA, USA), blue native polyacrylamide gel electrophoresis (BN-PAGE), and western blot analysis. For assessment of mitochondrial abnormalities, we measured the activity of mitochondrial Complex I and IV as well as uncoupling protein 2, and sirtuin 3 protein contents. Our results demonstrate that, under conditions mimicking the hyperglycemia, Complex I activity, UCP2, Complex III and IV subunits content, supercomplex formation, and acetylation levels are modified with respect to the control condition. However, basal oxygen consumption rate was not affected and mitochondrial reactive oxygen species production remained unchanged in all groups. Treatment of HepG2 cells with M. oleifera extract significantly increased both protein content and mitochondrial complexes activities. Nonetheless, control cells’ respiratory control ratio (RCR) was 4.37 compared to high glucose treated cells’ RCR of 15.3, and glucose plus M. oleifera treated cells’ RCR of 5.2, this indicates high-quality mitochondria and efficient oxidative phosphorylation coupling. Additionally, the state app was not altered between different treatments, suggesting no alteration in respiratory fluxes. These findings enhance understanding of the actions of M. oleifera and suggest that the known antidiabetic property of this plant, at least in part, is mediated through modulating the mitochondrial respiratory chain.

19.
Artigo em Inglês | MEDLINE | ID: mdl-28420209

RESUMO

Blood lead levels (BLLs) and delta-aminolevulinic acid dehydratase (ALAD) activity are considered biomarkers of lead exposure and lead toxicity, respectively. The present study was designed to investigate the association between BLLs and ALAD activity in pregnant women from Durango, Mexico. A total of 633 pregnant women aged 13-43 years participated in this study. Blood lead was measured by a graphite furnace atomic absorption spectrometer. ALAD activity was measured spectrophotometrically. Mean blood lead was 2.09 ± 2.34 µg/dL; and 26 women (4.1%) crossed the Centers for Disease Control (CDC) recommended level of 5 µg/dL. ALAD activity was significantly lower in women with levels of lead ≥5 µg/dL compared to those with BLLs < 5 µg/dL (p = 0.002). To reduce the influence of extreme values on the statistical analysis, BLLs were analyzed by quartiles. A significant negative correlation between blood lead and ALAD activity was observed in the fourth quartile of BLLs (r = -0.113; p < 0.01). Among women with blood lead concentrations ≥2.2 µg/dL ALAD activity was negatively correlated with BLLs (r = -0.413; p < 0.01). Multiple linear regression demonstrated that inhibition of ALAD in pregnant women may occur at levels of lead in blood above 2.2 µg/dL.


Assuntos
Chumbo/sangue , Sintase do Porfobilinogênio/sangue , Adolescente , Adulto , Biomarcadores/sangue , Estudos Transversais , Feminino , Humanos , Intoxicação por Chumbo/sangue , Modelos Lineares , México , Sintase do Porfobilinogênio/metabolismo , Gravidez , Espectrofotometria Atômica , Adulto Jovem
20.
J Pediatr ; 185: 205-210.e1, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28343659

RESUMO

OBJECTIVE: To examine the role of iron and zinc in arsenic excretion and metabolism in children. STUDY DESIGN: An analysis of urinary arsenic (UAs) concentrations from a double-blind randomized trial originally testing the efficacy of iron and zinc for lowering blood lead levels in children. A 2 × 2 factorial design was used, with children randomized individually, stratified by sex and classroom, to receive 30?mg ferrous fumarate (n?=?148), 30?mg zinc oxide (n?=?144), iron and zinc together (n?=?148), or placebo (n?=?151). Of the 602 children enrolled, 527 completed the 6-month treatment, and 485 had both baseline and final UAs values. The baseline total UAs concentration ranged from 3.2 to 215.9?µg/L. RESULTS: At baseline, children in the highest tertile of serum ferritin concentration had higher excretion of dimethylarsinic acid (DMA; 1.93?±?0.86%; P?

Assuntos
Arsenicais/urina , Ácido Cacodílico/urina , Suplementos Nutricionais , Compostos Ferrosos/administração & dosagem , Oligoelementos/administração & dosagem , Óxido de Zinco/administração & dosagem , Arsênio/urina , Criança , Método Duplo-Cego , Exposição Ambiental/efeitos adversos , Feminino , Ferritinas/sangue , Humanos , Masculino , México , Água/química , Abastecimento de Água
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