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1.
Acta bioquím. clín. latinoam ; 53(3): 307-314, set. 2019. tab
Artigo em Espanhol | LILACS | ID: biblio-1038100

RESUMO

El propósito de este estudio fue identificar la relación entre la masa grasa expresada como porcentaje de grasa corporal (%GC) medida por el método de deuterio (D2O) e indicadores antropométricos en escolares costarricenses. Se trata de un estudio descriptivo transversal en el que participaron 54 niños y 49 niñas de 6 a 9 años. Se realizaron medidas antropométricas: peso, talla, índice de masa corporal, circunferencia de brazo, circunferencia de cintura, circunferencia abdominal, pliegue cutáneo subescapular y pliegue cutáneo tricipital. El análisis del %GC se realizó por medio del método de referencia del D2O. Se realizó una estadística descriptiva y se aplicó un análisis de coeficiente de correlación de Pearson para identificar la relación entre las mediciones antropométricas y el %GC obtenido por D2O. En el grupo de escolares, las niñas presentaron valores mayores de talla y pliegue cutáneo tricipital (p<0,05) y %GC obtenida por D2O (p<0,001). Se observó una fuerte correlación entre el %GC medido por D2O y el índice de masa corporal, la circunferencia de cintura y la circunferencia abdominal tanto en los niños como en las niñas. Se concluye que la circunferencia de cintura y la circunferencia abdominal podrían ser utilizadas conjuntamente con el IMC como herramientas para el diagnóstico de sobrepeso y obesidad en población escolar, cuando no se cuente con metodologías más precisas que determinen el %GC.


The purpose of this study was to identify the relationship between fat mass (FM) expressed as body fat percentage (%BF) measured by the deuterium method (D2O) and anthropometric indicators in Costa Rican schoolchildren. A cross-sectional descriptive study was performed and the participants were 54 boys and 49 girls of ages between six and nine years old. The anthropometric measurements recorded were weight, height, body mass index (BMI), arm circumference (AC), waist circumference (WC), abdominal circumference (AC), subscapular skinfold (SSF), and tricipital skinfold (TSF). The analysis of %BF was performed by means of D2O reference method. Descriptive statistics and the application of Pearson correlation coefficient analysis identified the relationship between anthropometric measurements and %BF obtained by D2O. From the group of schoolchildren, the girls showed greater values for height and tricipital skinfold (p<0.05) and %BF obtained by D2O (p<0.001). This study evidences a strong correlation between %BF measured by D2O and BMI, WC and AC in both girls and boys. It is concluded that WC and AC could be used together with the IMC as tools for the diagnosis of overweight and obesity in schoolchildren, when there are no more precise methodologies that determine the %BF.


O objetivo deste estudo foi identificar a relação entre a massa gordurosa (MG), expressa como percentagem de gordura corporal (%GC) medida pelo método de deutério (D2O) e indicadores antropométricos em escolas da Costa Rica. Trata-se de um estudo descritivo transversal, no qual participaram 54 meninos e 49 meninas com idade entre seis e nove anos. Foram realizadas medidas antropométricas: peso, tamanho, índice de massa corporal (IMC), circunferência do braço (CB), circunferência da cintura (CC), circunferência abdominal (CA), prega cutânea subescapular (PCS) e prega cutânea tricipital (PCT). A análise da %GC foi realizada pelo método de referência D2O, realizou-se uma estatística descritiva e foi aplicada análise coeficiente de correlação de Pearson para identificar a relação entre as medições antropométricas e a %GC obtida por meio do D2O. No grupo de escolares, as meninas apresentaram maiores valores de estatura e PCT (p<0,05) e %GC obtida por D2O (p<0,001). Observou-se uma importante correlação entre %GC medida por D2O e IMC, CC e CA tanto nos meninos quanto nas meninas. Conclui-se que a CC e a CA poderiam ser utilizadas conjuntamente com o IMC como ferramenta para o diagnóstico de sobrepeso e obesidade em população escolar, quando não se conte com metodologias mais precisas que determinem o %GC.


Assuntos
Humanos , Masculino , Feminino , Criança , Pesos e Medidas Corporais/estatística & dados numéricos , Antropometria , Epidemiologia Descritiva , Estudos Transversais , Costa Rica/epidemiologia , Deutério , Distribuição da Gordura Corporal/estatística & dados numéricos , Obesidade/diagnóstico
2.
Nutrire Rev. Soc. Bras. Aliment. Nutr ; 42: 1-10, Dec. 2017. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-880962

RESUMO

BACKGROUND: Little information is available on the validity of anthropometry or impedance-based equations for prediction of total body water (TBW) in African children. This study was designed to validate and develop equations to predict total body water in Cameroonian children. METHODS: TBW was measured by deuterium dilution in 102 children between 24 and 60 months of age and compared with the ones predicted by 5 anthropometric and 7 BIA equations. Multiple linear regression analysis was used to develop prediction equations for TBW from anthropometric parameters. RESULTS: Unacceptable discrepancies in the estimates of TBW at individual level were noted with all the equations tested. The following new anthropometry and BIA equations for the estimation of TBW were respectively developed: TBW = 6.488 + 0.434 × sex−0.039 × age + 0.670 × weight−0.081 × MUAC (cm)−0.372 × BMI (adjustedR2= 0.71,RMSE = 3.6), and TBW =−6.206 + 0.0037 × height2/Z−0.041 × age + 0.265 × weight + 0.1214 × height (adjustedR2=0.68, RMSE = 1.4). The cross-validation procedures revealed that the predicted values of TBW compared with measured values are accurate at a group level. CONCLUSION: The current published anthropometric and BIA equations are invalid for the estimation of TBW in Cameroonian preschool children. The newly developed anthropometry or BIA prediction equations are valid for use in Cameroonian children aged 24­60 months


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Antropometria/métodos , Água Corporal/química , Deutério/análise , Deutério/farmacocinética , Impedância Elétrica
3.
Acta bioquím. clín. latinoam ; 51(2): 249-256, jun. 2017. graf, tab
Artigo em Espanhol | LILACS | ID: biblio-886119

RESUMO

El objetivo del trabajo fue describir la aplicación de la técnica de dilución isotópica con deuterio de dosis a la madre para determinar la ingesta de leche materna y la composición corporal de las madres, en distintos tipos de lactancia. El método analítico se aplicó en cuatro casos modelo de pares madre-lactante en los cuales las madres recibieron una dosis oral de agua deuterada, recolectándose 6 muestras de saliva de ambos durante 15 días. El enriquecimiento de deuterio se determinó en un espectrómetro FTIR-Shimadzu-Affinity obteniéndose la ingesta de leche materna (ILM) y de agua de otras fuentes (Fd). Se observó una variación del enriquecimiento de deuterio en la saliva del lactante, asociada al tipo de lactancia recibida, siendo mayor en el caso de lactancia materna exclusiva (LME). Asimismo, a medida que aumentó Fd, disminuyó ILM. Además, fueron determinadas el agua corporal, la masa libre de grasa y la masa grasa materna. La transferencia de las habilidades técnicas y del conocimiento a través de metodologías innovadoras para determinar la ingesta de leche materna es de utilidad como herramienta de evaluación de la alimentación del lactante y para investigar en qué medida la lactancia natural es reemplazada por la ingesta de otros alimentos. Mejorar la estimación de la LME contribuye al conocimiento de la recomendación de OMS y UNICEF de mantener la misma hasta el sexto mes de vida.


The aim of this study was to describe the application of the dose-to-the-mother deuterium-oxide turnover technique to determine the breast milk intake and body composition of mothers in different types of breastfeeding. This analytical method was performed in four mother-infant pairs at 4 months from birth. Mothers received an oral dose of deuterated water, collecting 6 samples of saliva from mother and baby during a period of 15 days. Deuterium enrichment was determined in a Shimadzu FTIR-spectrometer-Affinity to obtain the intake of breast milk and water from non-breast milk sources. In this study, a variation of the enrichment of deuterium in the saliva of the infant was observed, being higher when the infant was exclusively breastfed. As non-breast milk water increased, the intake of human milk decreased. Furthermore, maternal total body water, fat free mass and fat mass were determined. To improve technical skills and knowledge through innovative methods of breast milk measurement can be useful as an assessment tool for evaluating infant feeding and investigating the extent to which breast milk is being replaced by the consumption of other foods in order to estimate exclusive breastfeeding in the future. This would contribute to the knowledge of maintaining breastfeeding until the sixth month of life, as it is recommended by WHO and UNICEF.


O objetivo deste estudo foi descrever a aplicação da técnica de diluição isotópica com deutério de dose à mãe para determinar a ingestão de leite materno e a composição corporal das mães, em diferentes tipos de aleitamento. O método analítico foi aplicado em quatro casos modelo de pares mães-lactante nos quais as mães receberam uma dose oral de água deuterada, coletando-se 6 amostras de saliva de ambos (mães e lactantes) durante 15 días. O enriquecimento de deutério foi determinado em um espectrômetro FTIR-Shimadzu-Affinity, sendo obtida a ingestão de leite materno (ILM) e de água proveniente de outras fontes (Fd). Observou-se uma variação do enriquecimento de deutério na saliva do lactante, associada ao tipo de aleitamento recebido, sendo maior no caso de aleitamento materno exclusivo (AME). Também, na medida que aumentou Fd, diminuiu ILM. Além disso, a água corporal, a massa livre de gordura y a massa gorda materna foram determinadas. A transferência das habilidades técnicas e do conhecimento através de metodologias inovadoras para determinar a ingestão de leite materno é de utilidade como ferramenta de avaliação da alimentação do lactante e para investigar em que medida o aleitamento natural é substituído pela ingestão de outros alimentos. Melhorar a avaliação do AME contribui ao conhecimento da recomendação da OMS e UNICEF de manter a mesma até o sexto mês de vida.


Assuntos
Humanos , Feminino , Lactente , Deutério/análise , Leite Humano , Técnicas de Diluição do Indicador , Leite Humano/citologia
4.
Acta Physiologica Sinica ; (6): 311-315, 2017.
Artigo em Chinês | WPRIM | ID: wpr-348269

RESUMO

The aim of the present study was to measure the kinetic parameters of skeletal muscle protein synthesis in rats by deuterated water (HO). Twenty Sprague-Dawley (SD) rats were labeled byHO through intraperitoneal injection and drinking. At the each end of the 1st, 3rd, 5th, 6th and 10th week after the firstHO labeling, four rats were sacrificed by cardiac puncture for blood plasma and quadriceps femoris sampling. Skeletal muscle protein and free amino acids in plasma were purified, hydrolyzed by hydrochloric acid and derived. The deuterium enrichments ofH-labeled alanyl in skeletal muscle protein and plasma protein-boundH-labeled alanine were determined by gas chromatography-mass spectrometry (GC-MS). The fractional synthesis rate of skeletal muscle protein and synthetic dynamic equation were calculated. The fractional synthetic rate of skeletal muscle protein was 12.8%/week, and synthetic dynamic equation was f= 0.158 × (1 - e). The results suggest that the kinetic parameters of skeletal muscle protein synthesis can be measured byHO labeling, and the method can be applied in long-term labeling experiment.


Assuntos
Animais , Masculino , Ratos , Alanina , Aminoácidos , Sangue , Deutério , Cromatografia Gasosa-Espectrometria de Massas , Cinética , Proteínas Musculares , Músculo Esquelético , Metabolismo , Biossíntese de Proteínas , Ratos Sprague-Dawley , Água
5.
Arch. argent. pediatr ; 112(6): 537-541, dic. 2014. ilus
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1159651

RESUMO

Las técnicas nucleares aplicables al área de nutrición son inocuas dado que utilizan isótopos estables. En particular, la dilución isotópica con deuterio evalúa la composición corporal y la ingesta de leche materna. Es un método de referencia para conocer grasa corporal y validar herramientas de bajo costo debido a su exactitud, facilidad de aplicación y por la base de antecedentes de su utilización en adultos y niños. Es no invasiva ya que utiliza saliva como muestra de análisis, lo que la hace aplicable a poblaciones pediátricas. Modificaciones en la grasa se asocian a enfermedades no transmisibles y existen individuos con peso normal pero mayor depósito de grasa. Por ello, es de utilidad analizar sus cambios como instrumento de evaluación en clínica y en programas de salud. Además, esta técnica es la forma exacta de determinar si los lactantes son amamantados exclusivamente mediante seno materno, establecer lactancia materna exclusiva y validar métodos convencionales basados en encuestas a las madres.


The application of nuclear techniques in the area of nutrition is safe because they use stable isotopes. The deuterium dilution method is used in body composition and human milk intake analysis. It is a reference method for body fat and validates inexpensive tools because of its accuracy, simplicity of application in individuals and population and the background of its usefulness in adults and children as an evaluation tool in clinical and health programs. It is a non-invasive technique as it uses saliva, which facilitates the assessment in pediatric populations. Changes in body fat are associated with non-communicable diseases; moreover, normal weight individuals with high fat deposition were reported. Furthermore, this technique is the only accurate way to determine whether infants are exclusively breast-fed and validate conventional methods based on surveys to mothers.


Assuntos
Humanos , Lactente , Saliva/diagnóstico por imagem , Tecido Adiposo/diagnóstico por imagem , Estado Nutricional , Deutério/análise , Ingestão de Alimentos , Leite Humano
6.
Rev. Esc. Enferm. USP ; 48(spe): 59-66, 08/2014. tab
Artigo em Inglês | LILACS, BDENF | ID: lil-731296

RESUMO

Objective To evaluate the use and records of the Child Health Handbook (CHH), especially growth and development. Method Cross-sectional study with 358 mother-child pairs registered in 12 Primary Health Centers (PHCs) of a small municipality. Mothers were interviewed at the PHC from February to April 2013 using a questionnaire. Data analysis was done using WHO Anthro software, Epi InfoTM and Stata. Results Fifty-three percent of the mothers were carrying the CHH at the time of the interview, similar to the proportion of mothers who were instructed to bring the CHH to health appointments. Annotations in the CHH during the visits were reported by 49%. The vaccination schedule was completed in 97% of the CHH, but only 9% and 8% of the CHH, respectively, contained growth charts and properly completed developmental milestones. Conclusion Low rates of use and unsatisfactory record-keeping in the CHH reinforce the need for investment in professional training and community awareness for the CHH to become an effective instrument of promotion of child health. .


Objetivo Evaluar el uso y llenado de la Libreta de Salud Infantil (LSI), especialmente el crecimiento y el desarrollo. Método Estudio transversal con 358 pares de madres e hijos matriculados en 12 Unidades Básicas de Salud (UBS) de una ciudad pequeña. Las madres fueron entrevistadas en el UBS desde febrero a abril 2013 mediante un cuestionario. Se utilizó Epi-info y software SPSS. Resultados 53% de las madres estaban llevando LSI durante la entrevista, proporción similar a las madres que recibieron instrucciones para llevar el LSI a la atención de la salud. Anotaciones en LSI durante las visitas se registraron en un 49%. Calendario de vacunas fue completa en el 97% de LSI, pero sólo el 9% y el 8% de LSI tenido, respectivamente, las curvas de crecimiento y desarrollos debidamente cumplimentados. Conclusión El uso y el relleno satisfactorio de LSI refuerzan la necesidad de inversión en la formación profesional y el acercamiento a la comunidad para la LSI se convierte efectivamente en un instrumento de promoción de la salud infantil.
 .


Objetivo Avaliar uso e preenchimento da Caderneta de Saúde da Criança (CSC), especialmente crescimento e desenvolvimento. Método Estudo transversal com 358 pares mãe-criança atendidos em 12 Unidades Básicas de Saúde (UBS) de município de pequeno porte. As mães foram entrevistadas nas UBS, de fevereiro a abril de 2013, com o uso de questionário. Utilizou-se softwares Epi-info e Stata. Resultados No momento da entrevista, 53% das mães portavam a CSC, proporção similar à de mães que referiram orientação para levar a CSC aos atendimentos de saúde. Anotações na CSC durante os atendimentos foram referidos por 49%. Esquema vacinal estava completo em 97% das CSC, mas apenas 9% e 8% das CSC tinham, respectivamente, gráficos de crescimento e desenvolvimento adequadamente preenchidos. Conclusão O uso e o preenchimento insatisfatório da CSC reforçam a necessidade de investimentos na capacitação dos profissionais e na sensibilização da comunidade para que a CSC se torne efetivamente um instrumento de promoção da saúde infantil. .


Assuntos
Fenilacetatos/química , Tetracloreto de Carbono , Óxido de Deutério , Deutério/química , Ligação de Hidrogênio , Espectrofotometria Infravermelho , Temperatura
7.
Chinese Journal of Biotechnology ; (12): 1454-1463, 2014.
Artigo em Chinês | WPRIM | ID: wpr-345579

RESUMO

In silico acquirement of the accurate residue details of protein on chromatographic media is a bottleneck in protein chromatography separation and purification. Here we developed a novel approach by coupling with H/D exchange and nuclear magnetic resonance to observe hen egg white lysozyme (HEWL) unfolding behavior adsorbed on cation exchange media (SP Sepharose FF). Analysis of 1D 1H-NMR shows that protein unfolding accelerated H/D exchange rate, leading to more loss of signal of amide hydrogen owing to exposure of residues and the more unfolding of protein. Analysis of two-dimensional hydrogen-hydrogen total correlation spectroscopy shows that lysozyme lost more signals and experienced great unfolding during its adsorption on media surface. However, for several distinct fragments, the protection degrees varied, the adsorbed lysozyme lost more signal intensity and was less protected at disorder structures (coil, bend, and turn), but was comparatively more protected against exchange at secondary structure domains (α-helix, β-sheet). Finally, the binding site was determined by electrostatic calculations using computer simulation methods in conjunction with hydrogen deuterium labeled protein and NMR. This study would help deeply understand the microscopic mechanism of protein chromatography and guide the purposely design of chromatographic process and media. Moreover, it also provide an effective tool to study the protein and biomaterials interaction in other applications.


Assuntos
Adsorção , Amidas , Cátions , Simulação por Computador , Deutério , Hidrogênio , Espectroscopia de Ressonância Magnética , Muramidase , Química , Estrutura Secundária de Proteína , Desdobramento de Proteína , Proteínas , Química
8.
Braz. j. med. biol. res ; 46(8): 722-727, ago. 2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-684526

RESUMO

Huntington's disease (HD) is a neurologic disorder that is not completely understood; its fundamental physiological mechanisms and chemical effects remain somewhat unclear. Among these uncertainties, we can highlight information about the concentrations of brain metabolites, which have been widely discussed. Concentration differences in affected, compared to healthy, individuals could lead to the development of useful tools for evaluating the progression of disease, or to the advance of investigations of different/alternative treatments. The aim of this study was to compare the thalamic concentration of metabolites in HD patients and healthy individuals using magnetic resonance spectroscopy. We used a 2.0-Tesla magnetic field, repetition time of 1500 ms, and echo time of 135 ms. Spectra from 40 adult HD patients and 26 control subjects were compared. Quantitative analysis was performed using the LCModel method. There were statistically significant differences between HD patients and controls in the concentrations of N-acetylaspartate+N-acetylaspartylglutamate (NAA+NAAG; t-test, P<0.001), and glycerophosphocholine+phosphocholine (GPC+PCh; t-test, P=0.001) relative to creatine+phosphocreatine (Cr+PCr). The NAA+NAAG/Cr+PCr ratio was decreased by 9% and GPC+PCh/Cr+PCr increased by 17% in patients compared with controls. There were no correlations between the concentration ratios and clinical features. Although these results could be caused by T1 and T2 changes, rather than variations in metabolite concentrations given the short repetition time and long echo time values used, our findings point to thalamic dysfunction, corroborating prior evidence.


Assuntos
Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Doença de Huntington/metabolismo , Espectroscopia de Ressonância Magnética , Doenças Talâmicas/metabolismo , Tálamo/fisiopatologia , Ácido Aspártico/análise , Ácido Aspártico/análogos & derivados , Estudos de Casos e Controles , Creatina/análise , Deutério , Dipeptídeos/análise , Glicerilfosforilcolina/análise , Atividade Motora , Fosfocreatina/análise , Fosforilcolina/análise , Repetições de Trinucleotídeos , Doenças Talâmicas/diagnóstico
9.
Journal of Southern Medical University ; (12): 1394-1399, 2012.
Artigo em Chinês | WPRIM | ID: wpr-315455

RESUMO

<p><b>OBJECTIVE</b>To evaluate the inhibitory effect of deuterium-depleted water (DDW) on the proliferation of nasopharyngeal carcinoma (NPC) cells in vitro and explore the possible mechanism.</p><p><b>METHODS</b>The growth inhibition of NPC cells and preosteoblast MC3T3-E1 cells following DDW treatment was measured by MTT assay and plate colony formation assay. The changes in migration and invasion of NPC cells were evaluated using Transwell and boyden chamber assays. The protein expression of proliferating cell nuclear antigen (PCNA) was determined using Western blotting. Flow cytometry was employed to evaluate the changes in cell cycle distribution after DDW treatment.</p><p><b>RESULTS</b>DDW with deuterium concentrations of 100, 75 and 50 ppm significantly suppressed the cell proliferation (P<0.05) and lowered colony formation capacity and invasiveness of the NPC cells (P<0.01). Western blotting demonstrated a down-regulated expression of PCNA in the cells by DDW. DDW also caused obvious cell cycle arrest in the NPC cells with reduced cells in S phase and significantly increased cells in G(1) phase (P<0.05). Rather than causing growth inhibition, DDW promoted the growth of normal control MC3T3-E1 cells.</p><p><b>CONCLUSION</b>DDW possesses selective biological effects to inhibit the proliferation of NPC cells in vitro, suggesting the potential of DDW as a novel nontoxic adjuvant therapeutic agent in antitumor therapy.</p>


Assuntos
Humanos , Carcinoma , Linhagem Celular Tumoral , Proliferação de Células , Deutério , Farmacologia , Neoplasias Nasofaríngeas , Patologia , Antígeno Nuclear de Célula em Proliferação , Metabolismo , Água , Química
10.
Journal of Southern Medical University ; (12): 1454-1456, 2012.
Artigo em Chinês | WPRIM | ID: wpr-315443

RESUMO

Deuterium is an important predisposing factor for cancer. Deuterium-depleted Water, also known as low deuterium water, ultra-light water or no deuterium water, can be obtained by removing deuterium from natural water. Studies have shown that water with a low deuterium concentration (<65% percent of volume) can inhibit cancer growth. Clinical trials demonstrated that drinking DDW (10-20 ppm) caused growth arrest of malignant cells in cancer patients and significantly prolonged the patient survival with also improved quality of life. A wide range of anti-cancer drugs in current use are associated with severe adverse effects, while deuterium-depleted water appears to have virtually no pharmacological side effects and is convenient to administer. The authors review the advances in the researches of anti-cancer effects and the underlying mechanisms of deuterium-depleted water.


Assuntos
Animais , Humanos , Antineoplásicos , Deutério , Usos Terapêuticos , Neoplasias , Terapêutica , Água , Química
11.
China Journal of Chinese Materia Medica ; (24): 104-108, 2012.
Artigo em Chinês | WPRIM | ID: wpr-356112

RESUMO

<p><b>OBJECTIVE</b>Using the stable isotopes as the internal standard of microdialysis technology to establish a new method to study the whole and local brain dynamics of nicotine percutaneous preparations.</p><p><b>METHOD</b>Using th healthy rats as experimental animals, administrating nicotine in abdominal transdermal way, then sample in the blood and brain simultaneously by microdialysis which use deuterium nicotine (DL-nicotine) as internal standard. Detecting the samples by LC-MS/MS method.</p><p><b>RESULT</b>The configuration process in blood and brain both conforms to 2 compartments model, t1/2 is 29.38 min, t1/2beta is 208.51 min, AUC(0-infinity) is 152 127.10 microg x min x L(-1) in the blood t1/2 is 86.64 min, t1/2beta is 386.00 min, AUC(0-infinity) is 152 820.90 microg x min x L(-1) in the brain.</p><p><b>CONCLUSION</b>Dl-nicotine can be used as internal standard of nicotine to correcte the recovery; Stable isotopes internal standard microdialysis technology can be used for studing the whole and the local pharmacokinetic of nicotine and also provide new ideas and methods to studing the process of new drug delivery system.</p>


Assuntos
Animais , Masculino , Ratos , Encéfalo , Metabolismo , Química Encefálica , Deutério , Química , Marcação por Isótopo , Métodos , Microdiálise , Métodos , Nicotina , Sangue , Farmacocinética , Ratos Sprague-Dawley
12.
Acta Pharmaceutica Sinica ; (12): 333-337, 2011.
Artigo em Chinês | WPRIM | ID: wpr-348955

RESUMO

The paper is to report the study of pharmacokinetics of transdermal administered nicotine in the brain of freely moving rat by using microdialysis with stable labeled isotope as internal standard. The pharmacokinetic behavior of nicotine in Sprague Dawley rat brain was investigated after intranasal administration (3.75 mg). Brain fluid samples were collected by intracerebral microdialysis with DL-nicotine as internal standard. Concentrations of nicotine and DL-nicotine in the sample were measured by HPLC-MS/MS. Main pharmacokinetic parameters were calculated and analyzed by Das 2.0 pharmacokinetic software. The recovery of nicotine and the delivery of DL-nicotine were the same. The fate of absorption and distribution was two compartment model and the values of t1/2alpha was 170.31 min, t1/2beta was 263.30 min and the AUC(0-infinity) was 2.75 x 10(5) microg x L(-1) min separately. DL-nicotine can be used to calibrate the recovery of nicotine, and the new method of stable isotope microdialysis can be used to study the pharmacokinetics of freely moving rat. It will make sense for the treatment of addiction of tobacco and provide a new thought for the research of pharmacokinetics-pharmacodynamic combination.


Assuntos
Animais , Feminino , Masculino , Ratos , Administração Cutânea , Administração Intranasal , Área Sob a Curva , Encéfalo , Metabolismo , Cromatografia Líquida de Alta Pressão , Deutério , Marcação por Isótopo , Métodos , Microdiálise , Métodos , Nicotina , Farmacocinética , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem
13.
Iranian Journal of Arthropod-Borne Diseases. 2007; 1 (2): 19-26
em Inglês | IMEMR | ID: emr-102869

RESUMO

Blister beetles [Coleoptera: Meloidae] are the main natural source of cantharidin, but the compound titre is depended on several factors including, age, sex and mating status of the insects. In order to eliminate such uncertainty factors in physiological and chemical studies deuterium labelled cantharidin [D[2]C] with no natural abundance is normally introduced into the beetles' body to use it as a model for studying the cantharidin behaviour in vivo. Experiments were achieved on Mylabris quadripunctata [Col.: Meloidae] from Southern France and the beetles were exposed to an artificial diet containing a defined amount of D[2]C. On the other hand, because of the high similarity between the two compounds they cannot be well quantified by gas chromatography. In order to remove the burden, MRM technique was used for the first time which could successfully create well-defined cantharidin and D[2]C peaks and hence a precise measurement. MRM technique was examined using a GC-MS Varian Saturn which collected MS/MS data of more than one compound in the same time window of the chromatogram. It is especially useful when coeluting compounds have different parent ions, i.e. m/z 84 for D[2]C [coeluting isotopically-labelled compound] and m/z 82 for cantharidin [beetle-originated compound]. Using the routine GC-MS runs, measurement accuracy may be significantly reduced because the D[2]C peak is covered by the cantharidin huge peak while MRM could reveal the two coincided peaks of cantharidin and D[2]C. Therefore MRM is hereby introduced as the method of choice to separate cantharidin from D[2]C with high sensitivity and thus provide a precise base of quantitation


Assuntos
Insetos , Deutério , Besouros , Cromatografia Gasosa-Espectrometria de Massas
14.
Korean Journal of Urology ; : 1098-1105, 2005.
Artigo em Coreano | WPRIM | ID: wpr-111366

RESUMO

PURPOSE: To evaluate the antiproliferative activity of deuterium oxide (D2O) on urological cancer cells for the application of D2O in the treatment of urological cancer. MATERIALS AND METHODS: Urological cancer cell A-498 (kidney), T-24 (bladder) and DU 145 (prostate) were used in this study. The changes in cellular proliferation and the expressions of the bcl-2 and bax genes, according to changes in the D2O concentrationand exposure time were measured. The changes in cellular proliferation were measured using a hemocytometer and the MTT assay, and the changes in gene expression by Western hybridization. RESULTS: D2O had antiproliferative effects, DU-145 was most resistant and T-24 was most sensitive to D2O. The proliferation of cells in T-24, as measured by the MTT assay, showed a reduced growth rate, which was the inverse of the increased D2O concentration and exposure time. The expression of bcl-2 was reduced with increasing exposure time and D2O concentration, and that of bax was increased with increasing exposure time and D2O concentration. CONCLUSIONS: From this study, the authors believe D2O has antiproliferative effects on urological cancers, and the effect on bladder cancer cells suggests that D2O shows potential as an agent for the treatment of early small bladder cancer or the prevention of superficial bladder cancer recurrence following transurethral resection.


Assuntos
Proliferação de Células , Óxido de Deutério , Deutério , Expressão Gênica , Recidiva , Neoplasias da Bexiga Urinária , Neoplasias Urológicas
15.
Rev. chil. pediatr ; 74(5): 504-510, sept. 2003. tab, graf
Artigo em Espanhol | LILACS | ID: lil-362885

RESUMO

Introducción: La diálisis peritoneal (DP) en pediatría es acutalmente el tratamiento más utilizado para el reemplazo de la función renal en niños portadores de insuficiencia renal crónica. El ajuste de la dósis de análisis (Kt/V) debe ser periódico, lo cual requiere estimar el agua corporal total (ACT), lo que se puede realizar por distintas fórmulas. El método ideal de la medición del ACT se basa en el uso de isótopos marcados, H2[18 O] o D2O (deuterio), no aplicables en forma rutinaria a la práctica clínica. Objetivo: Estimar el ACT con deuterio en pacientes pediátricos en DP y compararla con las fórmulas de uso clínico habitual, calcular la dosis de diálisis-Kt/V- según el ACT obtenido por las distintas fórmulas y con deuterio. Pacientes y Métodos: Se evaluaron 8 pacientes en diálisis peritoneal crónica ambulatoria, 6 varones, edad (mediana) 6,6 años (4-14). Se realizo la medición de agua corporal por dilución isotópica con deuterio según protocolo de Plateau, administrando una dosis 1-2 gramos de deuterio al 99,9 por ciento, y recolectando una muestra de saliva basal y post-dosis a las 2, 3 y 4 horas; se comparó el resultado de esta medición con las fórmulas de Mellits y Cheek, y (ACT= kg* 0,6). Para el análisis estadístico se utilizó test de Student y test de Bland y Altman, considerando un p significativo < 0,05. Resultados: La estimación de ACT por deuterio es 2,9 por ciento inferior a la estimación del ACT por Mellits y Cheek y 1,6 por ciento superior que la estimación del ACT por kilos. El valor promedio del Kt/V calculando el ACT por las distintas fórmulas fue de: 2,08, 2,08 y 1,9 respectivamente (p n.s.). Conclusión: Las fórmulas de uso habitual en clínica para estimar el ACT no muestran diferencias significativas en este grupo de pacientes en diálisis peritoneal en comparación a su estimación por deuterio, lo cual permitiría su uso rutinario con un adecuado nivel de confianza.


Assuntos
Humanos , Pré-Escolar , Adolescente , Recém-Nascido , Lactente , Criança , Água Corporal , Deutério , Diálise Peritoneal , Insuficiência Renal Crônica
16.
Rev. chil. pediatr ; 74(1): 37-45, ene.-feb. 2003. tab, graf
Artigo em Espanhol | LILACS | ID: lil-342327

RESUMO

Se desarrollaron ecuaciones predictivas antropométricas para estimar agua y grasa corporal en 106 niños (3 a 5 años), asistentes a establecimientos de la junta nacional de jardines infantiles (JUNJI), utilizando la dilución isotópica con deuterio como método de referencia. Las ecuaciones se construyeron mediante regresión múltiple, evaluándose el acuerdo con las mediciones de la referencia mediante análisis de concordancia. El valor de R² fue alto en los modelos para agua (L) y grasa (kg) (0,7 y 0,64), mientras que para porcentaje de grasa fue menor (0,42). El análisis de concordancia reveló que la diferencia promedio entre la referencia y cada ecuación es baja biológicamente: 0,008 L, 0,012 kg y -0,06 porciento. La desviación estándar de las diferencias entre los valores determinados fue de 0,85 L, 1,09 kg y 5,9 porciento, respectivamente, considerándose altos para estudios individuales precisos. Se propone utilizar estos modelos en estudios poblacionales de este rango de edad


Assuntos
Humanos , Masculino , Pré-Escolar , Feminino , Antropometria , Composição Corporal/fisiologia , Água Corporal , Pesos e Medidas Corporais , Deutério , Dobras Cutâneas , Avaliação Nutricional , Distúrbios Nutricionais , Estado Nutricional , Obesidade
17.
Acta Pharmaceutica Sinica ; (12): 767-770, 2003.
Artigo em Chinês | WPRIM | ID: wpr-266607

RESUMO

<p><b>AIM</b>To study the NMR phenomena of cetirizine hydrochloride and assign all proton and carbon signals in NMR spectra.</p><p><b>METHODS</b>To record the 1D and 2D NMR spectra of cetirizine hydrochloride while changing the experimental temperature and adding D2O into the solution.</p><p><b>RESULTS</b>More than one NMR signal or broad peak resulting from piperazine and the attached groups with N atom were given in DMSO-d6 solution at room temperature. "Coalescence" or narrowing had occurred for the proton and carbon signals when the experimental temperature was increased or D2O was added into the solution.</p><p><b>CONCLUSION</b>Compared with the NMR "time scale", there are more than one conformation of cetirizine hydrochloride in DMSO-d6 solution at room temperature. The different conformation will be exchanged fast while temperature rise and the stable conformation will be existed while D2O was added into the solution.</p>


Assuntos
Cetirizina , Química , Deutério , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Conformação Proteica , Temperatura
18.
Rev. méd. Chile ; 125(11): 1335-42, nov. 1997. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-210353

RESUMO

Background: The degree of agreement bbetween different methods to assess total body composition is not well known. Aim: To determine the level of agreement for total body fat mass measurement by dual-photon absorptiometry (DEXA), bioelectrical impedance (BIA) and anthropometry using the deuterium dilution method as the gold-standard technique, in normal male volunteers. Subjects and methods: Total body fat mass was measured by DEXA, BIA, anthropometry and deuterium dilution in thirty one healthy men, aged 41.9 ñ 8.6 years old. Results: Mean differences in percentage of total body fat compared with deuterium dilution were 0.3 percent ñ 2.2, 1.3 percent ñ 3.4 and 1.8 ñ 2.3 percent for DEXA had the lower difference with deuterium dilution and the confidence intervals for this difference (ñDS) showed that, at the individual leve, the maximum difference was 4.4 percent. Conclusions: All the methods evaluated gave similar average measurements for total body fat mass, but with different individual variability. In this group of healthy male subjects, DEXA was the best method in terms of agreement with the gold-standard


Assuntos
Masculino , Humanos , Adulto , Antropometria , Composição Corporal , Dobras Cutâneas , Absorciometria de Fóton , Tecido Adiposo/anatomia & histologia , Saúde , Deutério , Impedância Elétrica
19.
Indian J Physiol Pharmacol ; 1997 Jan; 41(1): 47-51
Artigo em Inglês | IMSEAR | ID: sea-108711

RESUMO

Total Body Water (TBW) was measured in a group of 20 healthy adult Indian men and 10 women by the deuterated water dilution technique and their body composition was determined by applying a hydration factor of 0.7194 for fat free mass (FFM). The TBW in the male subjects whose mean body weight was 49.8 +/- 6.7 kg, was 60.6 +/- 3.2% of body weight (range 55.8%-65.4%), from which a FFM of 41.9 +/- 6.1 kg (range 31.8 kg-51.3 kg) was obtained. Total body water in the group of 10 female subjects whose mean body weight was 42.7 +/- 4.9 kg, was 57.0 +/- 4.5% of body weight (range 52.5%-64.2%) from which a FFM of 34.0 +/- 5.1 kg (range 28.4 kg-39.4 kg) was obtained.


Assuntos
Adulto , Compartimentos de Líquidos Corporais , Índice de Massa Corporal , Água Corporal/química , Deutério/diagnóstico , Feminino , Humanos , Técnicas de Diluição do Indicador , Masculino , Fatores Sexuais
20.
Korean Journal of Nephrology ; : 495-500, 1997.
Artigo em Inglês | WPRIM | ID: wpr-151554

RESUMO

Bioelectrical impedance analysis (BIA) was used to determine total body water (TBW) and lean body mass (LBM) in patients with renal failure. The body's electrical resistance (R) was measured by the voltage to current ratio, injecting an 800microA alternating current with a frequency of 50KHZ and detecting a voltage drop between the wrist and the ankle. Impedance index (Height2/Resistance) compared favorably with TBW measured by deuterium (D2O) dilution method as the reference, giving the correlation coefficient (r) of 0.966 and standard error estimation (SEE) of 2.71 liter. The index was compared with LBM determined by dual-energy x-ray absorptiometry (DEXA) as the reference, giving r of 0.970 and SEE of 3.00kg. The r of 0.985 and SEE of 2.15kg were found between the reference method. BIA appeared to have a somewhat lower accuracy than those of the reference method. However, it is a useful clinical tool for estimating body composition, because it is easy, rapid and non-invasive. The existing BIA method is based on an extremely simple conductor model of the body. The accuracy may be improved further, based on a more realistic model for the body.


Assuntos
Humanos , Absorciometria de Fóton , Tornozelo , Composição Corporal , Água Corporal , Deutério , Impedância Elétrica , Insuficiência Renal , Punho
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