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1.
Eur J Clin Nutr ; 77(5): 515-524, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35705857

RESUMO

BACKGROUND: Predictive equations are the best option for assessing fat mass in clinical practice due to their low cost and practicality. However, several factors, such as age, excess adiposity, and ethnicity can compromise the accuracy of the equations reported to date in the literature. OBJECTIVE: To develop and validate two predictive equations for estimating fat mass: one based exclusively on anthropometric variables, the other combining anthropometric and bioelectrical impedance variables using the 4C model as the reference method. SUBJECTS/METHODS: This is a cross-sectional study that included 386 Hispanic subjects aged ≥60 with excess adiposity. Fat mass and fat-free mass were measured by the 4C model as predictive variables. Age, sex, and certain anthropometric and bioelectrical impedance data were considered as potential predictor variables. To develop and to validate the equations, the multiple linear regression analysis, and cross-validation protocol were applied. RESULTS: Equation 1 included weight, sex, and BMI as predictor variables, while equation 2 considered sex, weight, height squared/resistance, and resistance as predictor variables. R2 and RMSE values were ≥0.79 and ≤3.45, respectively, in both equations. The differences in estimates of fat mass by equations 1 and 2 were 0.34 kg and -0.25 kg, respectively, compared to the 4C model. This bias was not significant (p < 0.05). CONCLUSIONS: The new predictive equations are reliable for estimating body composition and are interchangeable with the 4C model. Thus, they can be used in epidemiological and clinical studies, as well as in clinical practice, to estimate body composition in older Hispanic adults with excess adiposity.


Assuntos
Adiposidade , Obesidade , Idoso , Humanos , Composição Corporal , Estudos Transversais , Hispânico ou Latino , Pessoa de Meia-Idade
2.
J Clin Densitom ; 25(4): 641-648, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34666938

RESUMO

The densitometry method estimates body composition based on cadaver reference values, mainly the fat-free mass density value of 1.100 g/cm3. However, several changes in fat-free mass components by aging, ethnicity, and excess adiposity could influence their density and affect body composition estimations. The present study aimed to compare the mean fat-free mass component values in older Hispanic adults to cadaver reference values. This cross-sectional study included a sample of 420 subjects aged ≥60 yr from northern Mexico. Fat-free mass was determined by the four-compartment model using air displacement plethysmography, the deuterium dilution technique, and dual-energy X-ray absorptiometry for body density, aqueous and mineral fractions of body weight, respectively. A 1-sample t test was used to compare the fat-free mass density and aqueous, mineral, and residue fractions of fat-free mass from subjects in the study to the assumed cadaver reference values. The mean fat-free mass density value for the total sample of older Hispanic adults (1.096 ± 0.011 g/cm3) was significantly (p < 0.001) lower than the assumed value of 1.100 g/cm3, except in obese older men. The mean aqueous fraction of fat-free mass (74.8 ± 3.3%) was higher than the assumed value of 73.8%, and the mean residue fraction of fat-free mass value was lower (18.3 ± 3.4%) than the reference value of 19.4%. Indeed, only the mean mineral fraction of fat-free mass value (6.8 ± 0.8%) was similar to the reference value. In the total sample, all characteristic mean fat-free mass values in these older Hispanic adults differed from cadaver reference values, except the mineral fraction of fat-free mass value.


Assuntos
Composição Corporal , Obesidade , Adulto , Masculino , Humanos , Idoso , Estudos Transversais , Absorciometria de Fóton , Hispânico ou Latino , Cadáver , Densidade Óssea , Tecido Adiposo/diagnóstico por imagem
3.
Clin Nutr ; 40(5): 3592-3600, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33419614

RESUMO

BACKGROUND/OBJECTIVES: Densitometry (Siri's and Brozek's equations), hydrometry (by the deuterium dilution technique), and dual-energy X-ray absorptiometry (DXA) are three methods for estimating body composition. However, because they are all based on certain assumptions, they may not be applicable to aged and obese subjects due to changes in their body composition. Hence, the validity of these "laboratory methods" could be affected in obese older people. The main aim was to assess the agreement between densitometry, hydrometry, and DXA with the 4-compartment (4C) model to estimate fat mass (FM) in obese older Hispanic-American adults. As secondary goals, we explored whether the bias in densitometry and hydrometry results could be improved by modifying the assumptions regarding fat-free mass (FFM) density and hydration factor (HF) values, respectively. In the case of DXA, we explored the factors that contribute to bias. SUBJECTS/METHODS: This is a cross-sectional study based on a sample of 171 obese subjects aged ≥60 years from 3 regions of northern Mexico. Body composition was assessed by the 4C model as the reference method and by all three laboratory methods. Agreement of the latter with the 4C model was probed by Bland and Altman analysis, a paired sample t-test, and simple linear regression analyses. In addition, the mean FFM density estimated in this sample, and HF values (published previously) of 0.737 and 0.753 for obese older Hispanic-American men and women, respectively, were considered as ethnic- and gender-specific values. These values were used to modify the densitometric and hydrometric equations in order to improve their bias. Finally, we tested whether the hydration status and indirect markers of adiposity are contributing factors to the bias of DXA using multiple linear regression analysis. RESULTS: Siri's equation overestimated FM by 0.57 kg (p < 0.01), while Brozek's equation, hydrometry, and DXA underestimated it by 1.24 kg, 0.89 kg, and 0.79 kg (p < 0.01), respectively, compared to the 4C model. The bias in the densitometry and hydrometry results was eliminated by substituting the ethnic- and gender-specific values into the equations. Finally, we found that hip circumference contributes to the bias in DXA. CONCLUSION: The densitometry, hydrometry, and DXA methods are not interchangeable with the 4C model for assessing fat mass in obese, older Hispanic-American adults. The lack of agreement could indicate that the assumptions of each method do not apply to this population.


Assuntos
Absorciometria de Fóton/métodos , Tecido Adiposo/diagnóstico por imagem , Composição Corporal/fisiologia , Técnicas e Procedimentos Diagnósticos/normas , Hispânico ou Latino , Idoso , Estudos Transversais , Densitometria , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/diagnóstico por imagem , Reprodutibilidade dos Testes
4.
Clin Nutr ; 40(6): 4394-4403, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33485708

RESUMO

BACKGROUND & AIMS: Breast cancer patients (BCP) during treatment often experience an increase in body weight and fat mass, and a decrease in muscle mass known as sarcopenic obesity, affecting their prognosis and quality of life. We aimed to evaluate the effect of a 6-month individualized food-based nutrition intervention program in nonmetastatic BCP body composition during treatment. METHODS: This is a pre-post study in recently diagnosed women with invasive ductal/lobular breast carcinoma (clinical stage I-III). The individualized nutrition intervention was based on the dynamic macronutrient meal equivalent menu method (MEM). Dietary plans were developed according to WCRF/AICR guidelines, BCP total energy expenditure, 1.2-1.5 g/kgBW/d of protein intake, 5-9 servings/day of fruits and vegetables, and a caloric restriction (500-1000 kcal/d) when applicable (BMI ≥ 25 kg/m2). Follow-up was every 2-weeks and a different diet menu was provided in each session during 6 months. Baseline and final measurements included the assessment of anthropometry, body composition, and physical activity. RESULTS: Twenty-two participants completed the study and at diagnosis 68% were overweighed or obese. After the 6-month nutrition intervention program, BCP lost 3.1 kg (p < 0.01) of body weight, 2.7 kg (p < 0.01) of fat-mass, 400 g (p < 0.01) of abdominal fat, 118 g (p < 0.05) of visceral fat, 1.2 kg/m2 of body mass index and 1.1 kg/m2 of fat mass index (p < 0.01). During the period, no changes were observed in bone mineral density (p = 0.3), fat-free mass (p = 0.1) and appendicular skeletal muscle mass (p = 0.2). Menopausal status in BCP did not modify the effect of the nutrition intervention. CONCLUSIONS: The individualized food-based nutrition intervention program empowered BCP to make informed healthy food choices within their personal preferences, socioeconomic and cultural background. With this type of intervention, nonmetastatic BCP reduced body weight, fat-mass, fat mass index, visceral and abdominal fat, while preserving skeletal muscle mass, during antineoplastic treatment. ClinicalTrials.govNCT03625635.


Assuntos
Tecido Adiposo , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Dieta Saudável , Gordura Intra-Abdominal , Músculo Esquelético , Terapia Nutricional , Adulto , Composição Corporal , Peso Corporal , Neoplasias da Mama/fisiopatologia , Restrição Calórica , Proteínas Alimentares/administração & dosagem , Metabolismo Energético , Feminino , Frutas , Humanos , Pessoa de Meia-Idade , Estado Nutricional , Verduras
5.
Nutrients ; 11(12)2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31795327

RESUMO

Age- and obesity-related body composition changes could influence the hydration factor (HF) and, as a result, body composition estimates derived from hydrometry. The aim of the present study was to compare the HF in older Hispanic-American adults to some published values. This cross-sectional study included a sample of 412 subjects, men and women, aged ≥60 years from northern Mexico. HF values were calculated based on the ratio of total body water-using the deuterium dilution technique-to fat-free mass, derived from the four-compartment model. The mean HF value for the total sample (0.748 ± 0.034) was statistically (p ≤ 0.01) higher than the traditionally assumed value of 0.732 derived from chemical analysis, the "grand mean'' value of 0.725 derived from in vivo methods, and the 0.734 value calculated for older French adults via the three-compartment model. The HF of the older women did not differ across the fat mass index categories, but in men the obese group was lower than the normal and excess fat groups. The hydration factor calculated for the total sample of older Hispanic-American people is higher than the HF values reported in the literature. Therefore, the indiscriminate use of these assumed values could produce inaccurate body composition estimates in older Hispanic-American people.


Assuntos
Composição Corporal , Água Corporal , Idoso , Envelhecimento , Estudos Transversais , Humanos , México , Pessoa de Meia-Idade
6.
Nat Plants ; 4(4): 201-204, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29610534

RESUMO

Although freelisting and semi-structured interviews are widespread methods in ethnobotany, few studies quantitatively examine how these methods may bias results. Using a comprehensive ethnobotanical inventory of palm species, uses and names in the Chácobo tribe of Bolivia, we show that interviews elicit more items than freelists, but the effect is sensitive to sample size, item type and data categorization. This implies that even subtle methodological choices may greatly affect reported results.


Assuntos
Etnobotânica/métodos , Plantas Medicinais , Bolívia , Humanos , Entrevistas como Assunto
7.
J Ethnobiol Ethnomed ; 14(1): 9, 2018 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-29373988

RESUMO

BACKGROUND: That the answers elicited through interviews may be influenced by the knowledge of the interviewer is accepted across disciplines. However, in ethnobotany, there is little evidence to quantitatively assess what impact this effect may have. We use the results of a large study of traditional ecological knowledge (TEK) of plant use of the Chácobo and Pacahuara of Beni, Bolivia, to explore the effects of interviewer identity and knowledge upon the elicited plant species and uses. METHODS: The Chácobo are a Panoan speaking tribe of about 1000 members (300+ adults) in Beni, Bolivia. Researchers have collected anthropological and ethnobotanical data from the Chácobo for more than a century. Here, we present a complete ethnobotanical inventory of the entire adult Chácobo population, with interviews and plant collection conducted directly by Chácobo counterparts, with a focus on the effects caused by external interviewers. RESULTS: Within this large study, with a unified training for interviewers, we did find that different interviewers did elicit different knowledge sets, that some interviewers were more likely to elicit knowledge similar to their own, and that participants interviewed multiple times often gave information as different as that from two randomly chosen participants. CONCLUSIONS: Despite this, we did not find this effect to be overwhelming-the amount of knowledge an interviewer reported on the research subject had comparatively little effect on the amount of knowledge that interviewer recorded from others, and even those interviewers who tended to elicit similar answers from participants also elicited a large percentage of novel information.


Assuntos
Modificador do Efeito Epidemiológico , Etnobotânica , Adulto , Idoso , Bolívia , Ecologia , Feminino , Humanos , Conhecimento , Masculino , Pessoa de Meia-Idade , Plantas Medicinais
8.
J Ethnobiol Ethnomed ; 13(1): 57, 2017 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-29017576

RESUMO

BACKGROUND: The Chácobo are a Panoan speaking tribe of about 1000 members (300+ adults) in Beni, Bolivia. Originally nomadic, the Chácabo were relocated to their current main location in the 1960s. Researchers have visited the Chácabo since 1911. A first more detailed anthropological report exists from the late 1960s, and ecological-ethnobotanical studies were conducted in the 1980s and 1990s. The presented work represents a complete ethnobotanical inventory of the entire adult Chácobo population, with interviews and plant collection conducted directly by Chácobo counterparts. METHODS: Based on previous reports and our preliminary studies, we hypothesized that twenty-first century Chácobo plant use centered on income generation, and that traditional plant use related to household utensils, medicine and traditional crop varieties had almost disappeared. To test this hypothesis, we started the "Chácobo Ethnobotany Project," training 10 indigenous Chácobo participants in ethnobotanical interview and plant collection techniques, in order to more fully document Chácobo knowledge and avoid the influence of foreign interviewers. RESULTS: Our study found 331 useful plant species in 241genera of 95 plant families, with leaves, roots and bark being the most commonly used plant parts The comprehensive documentation that these methods enabled completely nullified our initial hypothesis of knowledge loss. Traditional crop varieties are still widely grown and traditional knowledge is alive. Moreover, it is being actively recuperated in certain domains by the younger generation. Most Chácobo know, and can name, traditional utensils and tools, although only the older generation has still the skills to manufacture them. While many Chácobo still know the names and uses of medicinal species, the younger generation is however often unsure how to identify them. CONCLUSIONS: In this paper we illustrate the complexity of perspectives on knowledge at different ages, and the persistence of knowledge over almost a century. We found that traditional knowledge was only partially affected by the processes of exposure to a market economy, and that different knowledge domains experienced different trends as a result of these changes. Overall knowledge was widely distributed, and we did not observe a directional knowledge loss. We stress the importance to not directly conclude processes of knowledge loss, cultural erosion or acculturation when comparing the knowledge of different age groups.


Assuntos
Etnobotânica , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Bolívia , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Plantas Comestíveis , Adulto Jovem
9.
Nutr Hosp ; 30(4): 876-82, 2014 Oct 01.
Artigo em Espanhol | MEDLINE | ID: mdl-25335676

RESUMO

BACKGROUND: Breast cancer is the most commonly diagnosed malignancy in women in Mexico and also has the highest mortality. Although treatment has improved significantly, it can affect the nutritional status of the recipients. OBJECTIVE: The aim of this study was to assess the impact of the initial phase of antineoplastic therapy on the nutritional status in patients with breast cancer. METHODS: Forty subjects with primary diagnosed of invasive breast cancer were studied in a before and after intervention (six month apart) using a quasi-experimental design. Basal and six month after intervention measurements included were anthropometry, body composition by dual X-ray absorptiometry (DEXA), diet by 24-hour recall and food frequency questionnaire, as well as serum -carotene and retinol. The therapy effect was analyzed using repeated measurements mixed linear regression. RESULTS: Lean tissue decreased after the studied period (p=0.032). Addicionally, there was an interaction between weight, BMI and body fat parameters with menopausal status, increasing in these variables due to therapy only premenopausal patients (p=0.005, 0.006 and 0.001, respectively). Decreased serum retinol (p=0.049) despite the improvement in -carotene status (p=0.03). In general there was an increase the consumption of vegetables food products whilst a decrease in animal foods. CONCLUSION: The breast cancer antineoplastic treatment had a negative effect on weight and body fat, especially in young women. Although there were some positive dietary changes, vegetables consumption remained insufficient, which was also reflected in serum biomarkers.


Presentación: El cáncer de mama es el tipo de tumor más frecuentemente diagnosticado entre las mujeres de México y también el de más alta mortalidad. Aunque el tratamiento ha mejorado significativamente, puede afectar al estado nutricional del paciente. Objetivo: El objetivo de este estudio era evaluar el impacto de la fase inicial de la terapia antineoplásica sobre el estado nutricional en pacientes con cáncer de mama. Métodos: Cuarenta sujetos con diagnóstico primario de cáncer de mama invasivo fueron estudiados antes y después de la intervención (con seis meses de desfase) usando un diseño quasi-experimental. Las mediciones al inicio y seis meses después de la intervención incluyeron antropometría, composición corporal mediante absorciometría dual de rayos X (DEXA), cuestionario de recopilación de dieta en 24 horas y frecuencia de comidas, y suero beta-caroteno y retinol. El efecto de la terapia fue analizado empleando mediciones repetidas y regresión lineal mixta. Resultados: El tejido magro disminuyó tras el periodo de estudio (p=0.032). Además, se dio una interacción entre los parámetros de peso, IMC y grasa corporal con el estado de menopausia, aumentando en estas variables debido a la terapia solo en pacientes premenopáusicas (p=0.005, 0.006 y 0.001, respectivamente). Descenso de retinol sérico (p=0.049) a pesar de la mejoría en el estado de beta-caroteno (p=0.03). En general hubo un aumento en el consumo de verdura y un descenso de productos animales. Conclusión: El tratamiento antineoplásico del cáncer de mama tuvo un efecto negativo sobre el peso y la grasa corporal, especialmente en mujeres jóvenes. Aunque se observaron algunos cambios positivos en la dieta, el consumo de verdura siguió siendo insuficiente, lo que también se reflejó en los biomarcadores séricos.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/fisiopatologia , Estado Nutricional/efeitos dos fármacos , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Tempo
10.
Nutr. hosp ; 30(4): 876-882, oct. 2014. tab
Artigo em Espanhol | IBECS | ID: ibc-134918

RESUMO

Introducción: El cáncer de mama es la neoplasia más diagnosticada en mujeres en México y también la de mayor mortalidad. Aunque el tratamiento ha mejorado, puede afectar de forma importante el estado nutricio de quienes lo reciben. Objetivo: Evaluar el impacto del tratamiento antineoplásico sobre el estado nutricio en pacientes con cáncer de mama. Pacientes y métodos: Se aplicó un diseño cuasiexperimental, antes y después de seis meses del inicio del tratamiento quimioterapéutico. Participaron 40 pacientes con diagnóstico primario de cáncer de mama invasivo. Se tomaron medidas antropométricas, de composición corporal mediante absorciometría dual de rayos X (DEXA) así como análisis de la dieta mediante recordatorio de 24 horas y cuestionario de frecuencia de consumo. Además, se cuantificaron los biomarcadores séricos, retinol y Beta-caroteno. El efecto del tratamiento se estimó utilizando regresión linear mixta para mediciones repetidas. Resultados: Se registró una pérdida de tejido magro (p=0.03). Además se encontró interacción del climaterio sobre los parámetros de peso, IMC y grasa corporal; solo en las pacientes preclimatéricas aumentaron estas medidas (p=0.005, 0.006 y 0.001 respectivamente). El retinol sérico disminuyó (p=0.049) pese al incremento en el Beta-caroteno (p=0.030). También se incrementó el consumo de vegetales y hubo una reducción en el consumo de alimentos de origen animal. Conclusión: El tratamiento antineoplásico para cáncer de mama afectó negativamente al peso y grasa corporal, principalmente en las mujeres jóvenes. Pese a las modificaciones dietarias, el consumo promedio de vegetales aún es insuficiente, lo cual se reflejó también en los biomarcadores séricos (AU)


Background: Breast cancer is the most commonly diagnosis malignancy in women in Mexico and also has the highest mortality. Although treatment has improved significantly, it can affect the nutritional status of the recipients. Objective: The aim of this study was to assess the impact of the initial phase of antineoplastic therapy on the nutritional status in patients with breast cancer. Methods: Forty subjects with primary diagnosed of invasive breast cancer were study in a before and after intervention (six months apart) using a quasi-experimental design. Basal and six month after intervention measurements included were anthropometry, body composition by dual X-ray absorptiometry (DEXA), diet by 24-hour recall and food frequency questionnaire, as well as serum Beta-carotene and retinol. The therapy effect was analyzed using repeated measurements mixed linear regression. Results: Lean tissue decreased after the studied period (p=0.032).Addicionally, there was an interaction between weight, BMI and body fat parameters with menopausal status, increasing in these variables due to therapy only premenopausal patients (p=0.005, 0.006 and 0.001, respectively). Serum retinol decreased (p=0.049) despite the improvement in Beta-carotene status (p=0.03). In general there was an increase the consumption of vegetables food products whilst a decrease in animal foods products. Conclusion: The breast cancer antineoplasic treatment had a negative effect on weight and body fat, especially in young women. Although there were some positive dietary changes, vegetables consumption remained insufficient, which was also reflected in serum biomarkers (AU)


Assuntos
Humanos , Feminino , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Avaliação Nutricional , Distúrbios Nutricionais/epidemiologia , Composição Corporal , Pesos e Medidas Corporais/estatística & dados numéricos
11.
J Oral Pathol Med ; 42(6): 443-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23278731

RESUMO

BACKGROUND: Since the introduction of highly active antiretroviral therapy (HAART), an increase in the frequency of human papillomavirus-associated oral lesions (HPV-OL) has been observed. Thus, the aim of this study was to determine the prevalence and factors associated with HPV-OL in Mexican HIV-infected patients, as well as its genotyping, in the HAART era. METHODS: In a cross-sectional study developed at an HIV/AIDS referral center in Mexico City, HIV-infected patients were consecutively included from 2004 to 2011. An oral exam was performed; lymphocyte CD4(+) count, HIV-viral load, CDC-stage, and HAART use were recorded. HPV-OL samples were taken for routine histopathological analysis (H-E) and HPV-DNA amplification/sequencing. Logistic regression models were performed and the interactions tested using the STATA software. RESULTS: Among 787 HIV patients, 55 (6.9%) showed HPV-OL. HPV-OLs were independently associated with age (≥40 years) and with a longer time of HAART use (≥12 months). The most frequent lesion was squamous cell papilloma in 22 (40%) cases, followed by multifocal epithelial hyperplasia in 15 (27.3%) cases. Labial mucosa was the most common site involved (56.4%). Of the sequences obtained, 65.4% corresponded to low risk and 11.5% to high risk. Mixed high- and low-risk infection were identified in 7.7% of the cases. CONCLUSIONS: Human papillomavirus-associated oral lesions were associated with older age and longer HAART use. All lesions were benign in nature and most of the HPV sequences corresponded to low-risk types. The rise of HPV-OLs in HIV patients on HAART may be related with the longer life expectancy of individuals with an impaired immune system rather than a direct effect of HAART.


Assuntos
Alphapapillomavirus/fisiologia , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Doenças da Boca/virologia , Infecções por Papillomavirus/epidemiologia , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Adulto , Fatores Etários , Alphapapillomavirus/classificação , Alphapapillomavirus/genética , Terapia Antirretroviral de Alta Atividade/estatística & dados numéricos , Contagem de Linfócito CD4 , Estudos Transversais , DNA Viral/análise , Feminino , Hiperplasia Epitelial Focal/epidemiologia , Hiperplasia Epitelial Focal/virologia , HIV/isolamento & purificação , Humanos , Doenças Labiais/epidemiologia , Doenças Labiais/virologia , Masculino , México/epidemiologia , Doenças da Boca/epidemiologia , Neoplasias Bucais/epidemiologia , Neoplasias Bucais/virologia , Papiloma/epidemiologia , Papiloma/virologia , Análise de Sequência de DNA , Carga Viral
12.
J Nutr ; 143(2): 221-6, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23256139

RESUMO

Vitamin A (VA) deficiency (VAD) continues to be a major nutritional problem in developing countries, including Central America. In Mexico, milk is a well-accepted vehicle for the administration of micronutrients, including VA, to preschoolers. Thus, we conducted a randomized, controlled, clinical trial to investigate the efficacy of daily consumption of 250 mL of VA-fortified milk (which provided 196 retinol equivalents/d) for 3 mo on VA stores in mildly to moderately VAD (serum retinol concentration 0.35-0.7 µmol/L) preschoolers who were not enrolled in a food assistance program. Twenty-seven mildly to moderately VAD children were randomly assigned based on screening measurements to either the intervention (n = 14) or control group (n = 13) (children in the control group did not receive placebo). All children in the control group and 79% (n = 11) of the children in the intervention group completed the study. The total body VA (TBVA) pool size was estimated using the deuterated retinol dilution technique before and after the intervention. After 3 mo, median changes in the serum retinol concentration for the intervention and control groups were 0.13 and -0.21 µmol/L, respectively (P = 0.009). Median changes in the TBVA stores were 0.06 and 0.01 mmol, respectively (P = 0.006) and estimated median changes in the liver VA concentration were 0.09 and 0.01 µmol/g, respectively (P = 0.002). The VA-fortified milk was well accepted among preschoolers and significantly increased TBVA stores, liver VA stores, and serum retinol concentration, indicating that it may be an effective means to ameliorate VAD in young Mexican children.


Assuntos
Alimentos Fortificados , Leite , Deficiência de Vitamina A/dietoterapia , Vitamina A/metabolismo , Vitamina A/uso terapêutico , Animais , Criança , Pré-Escolar , Deutério , Países em Desenvolvimento , Dieta/efeitos adversos , Feminino , Preferências Alimentares , Alimentos em Conserva , Humanos , Técnicas de Diluição do Indicador , Fígado/metabolismo , Masculino , México , Pacientes Desistentes do Tratamento , Índice de Gravidade de Doença , Vitamina A/administração & dosagem , Vitamina A/sangue , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/etiologia , Deficiência de Vitamina A/fisiopatologia
13.
Rev. med. exp ; 18(3/4): 82-89, 2001. tab, graf
Artigo em Espanhol | LIPECS | ID: biblio-1110880

RESUMO

Objetivo. Estandarizar un medio de cultivo utilizando la infusión de espárrago (Asparagus officinalis) para la producción masiva de bacillus thurningiensis (Bti) H-14 bvar. israelensis y determinar el efecto biolarvicida del Bti sobre Anopheles sp en criaderos naturales del distrito Laredo durante los meses de enero a diciembre del 2000. Materiales y métodos: Se ensayaron 3 medios a base de infusión de espárragos blanco: M1: 100 mL de la infusión, pH 9; M2: 50 mL de la infusión con 50 mL de buffer fosfato, pH 7; y M3: 25 mL de la infusión con 75 mL de agua destilada, pH 9. Como control se utilizó biolarvicidad a través del LC50 y LC90. El medio de cultivo óptimo (menor LC50 y LC90) sirvió para la producción masiva del Bti, el cual se sometió a bioensayo de laboratorio y aplicaciones en criaderos naturales. La efectividad fue determinada mediante la densidad larvaria pre y post aplicación del Bti. Resultados: El medio de cultivo óptimo para la producción de Bti fue M1, mostrando alta efectividad, con 100 por ciento de mortalidad en condiciones de laboratorio y 71-97 por ciento de mortalidad en el campo a las 24 horas de exposición con 3 aplicaciones realizadas semanalmente. Conclusiones: M1 es el medio óptimo para cultivar Bti, con alta efectividad para controlar larvas de Anopheles en el laboratorio y en el campo.


Objective: To standardize a culture medium using asparagus infusion (Asparagus officinalis) for the massive production of Bacillus thurigiensis (Bti) H-14 var. israelensis and to determine Bti bio-larvicide effect upon Anopheles sp. in natural breeding sites in Laredo district from January to December, 2000. Materials and methods: Three media based on white asparagus infusion were tested: M1: 100-mL infusion, pH: 9; M 2: 50-mL infusion plus 50-mL buffer phosphate, pH: 7, and M 3: 25-mL infusion plus 75-mL distilled water, pH: 9. The standard TPH medium was used as a control. Bti production in the different culture media was assessed in order to determine the bio-larvicide effectiveness using LC50 and LC90 The optimum culture medium (lower values for LC 50 and LC90) served for Bti production, and it was evaluated in laboratory and natural breeding sites. Effectiveness was determined measuring larval density prior and after Bti application. Results: The optimum medium for Bti production was M,. It showed high effectiveness, with 100% mortality under laboratory conditions, and 71-97% mortality in the field after 24 hours of exposition with three weekly applications. Conclusions: M1 is the optimum medium for culturing Bti, with high effectiveness for controlling Anopheles larvae both under laboratory and field conditions.


Assuntos
Bacillus thuringiensis , Controle de Vetores de Doenças , Malária/prevenção & controle
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