Fluid intake of Latin American adults: results of four 2016 Liq.In7 national cross-sectional surveys.

PURPOSE: To report total fluid intake (TFI) and the intake of different fluid types in adults (≥ 18 years old) from Mexico, Argentina, Brazil and Uruguay. To compare intakes between countries and with recommended adequate intake (AI) of water from fluids. METHODS: Cross-sectional data were collected using a validated liquid intake 7-day record (Liq.In 7 ) in populations from Argentina (n = 1089), Brazil (n = 477), Mexico (n = 1677) and Uruguay (n = 554). Population characteristics, including age, gender, body mass index and socioeconomic level were recorded. Mean TFI was compared with the AI of water from fluids set by the USA Institute of Medicine. RESULTS: The lowest TFI was recorded in Mexican women (1748 mL/day) and the highest in Argentinean men (2318 mL/day). Median daily TFI was significantly different between countries; Uruguay and Argentina had higher values than Mexico and Brazil. In the former, plain water contributed to only 25% of TFI, the remainder being predominantly from hot beverages. Approximately, a third of adults did not drink enough fluid to meet the recommended AI. High SSB consumption was reported, which was significantly different between countries (p < 0.05), the highest being in Mexico (median 25-75th percentiles): 531 (300-895 mL/day. CONCLUSIONS: This survey highlights the need to increase water consumption and reduce SSB intake in this region to avoid potential associated health risks. These findings may be useful information in monitoring public health policy strategies.

Fluid intake of Latin American children and adolescents: results of four 2016 LIQ.IN 7 National Cross-Sectional Surveys.

PURPOSE: The primary aim of this survey was to report total fluid intake (TFI) and different fluid types for children (4-9 years) and adolescents (10-17 years) in Mexico, Brazil, Argentina and Uruguay. The second aim was to compare TFI with the adequate intake (AI) of water from fluids as recommended by the USA Institute of Medicine. METHODS: Data were collected using a validated liquid intake 7-day record (Liq.In 7 ). Participants' characteristics, including age, sex and anthropometric measurements were recorded. RESULTS: A total of 733 children and 933 adolescents were recruited. Over 75% of children in Uruguay met the IOM's recommended intake. Fewer children in Argentina (64-72%) and Brazil (41-50%) obtained AI and the lowest values were recorded in Mexico (33-44%), where 16% of boys and 14% girls drank 50% or less of the AI. More adolescents in Argentina (42%) met the AIs than other countries; the lowest was in Mexico (28%). Children and adolescents in Mexico and Argentina drank more sugar sweetened beverages than water. CONCLUSIONS: Large numbers of children and adolescents did not meet AI recommendations for TFI, raising concerns about their hydration status and potential effects on mental and physical well-being. Given the negative effects on children's health, the levels of SSB consumption are worrying.

Fluid intake patterns of children and adolescents: results of six Liq.In7 national cross-sectional surveys.

PURPOSE: This study aimed to identify and characterize patterns of fluid intake in children and adolescents from six countries: Argentina, Brazil, China, Indonesia, Mexico and Uruguay. METHODS: Data on fluid intake volume and type amongst children (4-9 years; N = 1400) and adolescents (10-17 years; N = 1781) were collected using the validated 7-day fluid-specific record (Liq.In7 record). To identify relatively distinct clusters of subjects based on eight fluid types (water, milk and its derivatives, hot beverages, sugar-sweetened beverages (SSB), 100% fruit juices, artificial/non-nutritive sweetened beverages, alcoholic beverages, other beverages), a cluster analysis (partitioning around k-medoids algorithm) was used. Clusters were then characterized according to their socio-demographics and lifestyle indicators. RESULTS: The six interpretable clusters identified were: low drinkers-SSB (n 523), low drinkers-water and milk (n 615), medium mixed drinkers (n 914), high drinkers-SSB (n 513), high drinkers-water (n 352) and very high drinkers-water (n 264). Country of residence was the dominant characteristic, followed by socioeconomic level, in all six patterns. CONCLUSIONS: This analysis showed that consumption of water and SSB were the primary drivers of the clusters. In addition to country, socio-demographic and lifestyle factors played a role in determining the characteristics of each cluster. This information highlights the need to target interventions in particular populations aimed at changing fluid intake behavior and improving health in children and adolescents.

A comparison of drinking behavior using a harmonized methodology (Liq.In 7 ) in six countries.

PURPOSE: To assess drinking occasions (volume and type) according to consumption with food in or outside meals, and location, for six countries. METHODS: A total of 10,521 participants aged 4-65 years from Argentina, Brazil, China, Indonesia, Mexico and Uruguay completed a validated 7-day fluid intake record. For each drinking event, the volume consumed, the fluid type, the location of intake, and whether the drink was accompanied by food (meal or snack) or not, was recorded. RESULTS: Similar drinking behaviors were found in Mexico and Argentina; fluid intake during meals was 48 and 45% of total fluid intake (TFI), respectively. In Brazil (55%), Indonesia (58%) and China (66%) most fluid was consumed without food. In Uruguay, 34% of TFI was with a main meal, 31% with food between meals and 35% without food. Indonesia had the highest median (25-75th percentile) TFI; 2520 (1750-3347) mL/day, and China the lowest 1138 (818-3347) mL/day. Water was consumed with meals for 37% of Chinese and 87% of Indonesian participants, while the four Latin-American American countries showed a preference for sweet drinks; 54% in Mexico, 67% in Brazil, 55% in Argentina and 59% in Uruguay. Diversity in fluid type was noted when drinking with food between meals. Apart from China, most drinking occasions (> 75%) occurred at home. CONCLUSIONS: Three distinct drinking behaviors were identified, namely, drinking with meals, drinking as a stand-alone activity, and a type of 'grazing' (i.e., frequent drinks throughout the day) behavior. Most drinking occasions occurred at home.

Intake of water and different beverages in adults across 13 countries.

PURPOSE: To describe the intake of water and all other fluids and to evaluate the proportion of adults exceeding the World Health Organisation (WHO) recommendations on energy intake from free sugar, solely from fluids. METHODS: A total of 16,276 adults (46 % men, mean age 39.8 years) were recruited in 13 countries from 3 continents. A 24-h fluid-specific record over 7 days was used for fluid assessment. RESULTS: In Spain, France, Turkey, Iran, Indonesia and China, fluid intake was characterised by a high contribution of water (47-78 %) to total fluid intake (TFI), with a mean water intake between 0.76 and 1.78 L/day, and a mean energy intake from fluids from 182 to 428 kcal/day. Between 11 and 49 % of adults exceeded the free sugar WHO recommendations, considering solely fluids. In Germany, UK, Poland and Japan, the largest contributors to TFI were hot beverages (28-50 %) and water (18-32 %). Mean energy intake from fluids ranged from 415 to 817 kcal/day, and 48-62 % of adults exceeded free sugar WHO recommendations. In Mexico, Brazil and Argentina, the contribution of juices and regular sugar beverages (28-41 %) was as important as the water contribution to TFI (17-39 %). Mean energy intake from fluids ranged 565-694 kcal/day, and 60-66 % of the adults exceeded the free sugar WHO recommendation. CONCLUSIONS: The highest volumes recorded in most of the countries were for water, mean energy intake from fluids was up to 694 kcal/day, and 66 % of adults exceeded the free sugar WHO recommendation solely by fluids. Actions to create an environment in favour of water consumption and reduce sugar intake from fluids therefore are warranted.

Intake of water and beverages of children and adolescents in 13 countries.

PURPOSE: To describe the intake of water and all other beverages in children and adolescents in 13 countries of three continents. METHODS: Data of 3611 children (4-9 years) and 8109 adolescents (10-17 years) were retrieved from 13 cross-sectional surveys (47 % males). In three countries, stratified cluster sampling design was applied to randomly recruit schools classes. A quota method was applied in the other countries to randomly recruit participants. Details on the intake of all fluid types were obtained with a fluid-specific record over 7 consecutive days. RESULTS: In the total sample, the highest mean intakes were observed for water (738 ± 567 mL/day), followed by milk (212 ± 209 mL/day), regular soft beverages (RSB) (168 ± 290 mL/day) and juices (128 ± 228 mL/day). Patterns characterized by a high contribution of water, RSB or hot beverages to total fluid intake were identified among the countries with close geographical location. Adolescents had a significantly lower milk intake and higher intake of RSB and hot beverages than children in most countries. The most consistent gender difference observed was that in both age groups males reported a significantly higher RSB consumption than females. CONCLUSION: On average, water was the fluid consumed in the largest volume by children and adolescents, but the intake of the different fluid types varied substantially between countries. Since the RSB intake was as large, or even larger, than water intake in some countries, undertaking actions to improve fluid intake habits of children and adolescents are warranted.

Impacto de la obesidad central en el diagnóstico de cáncer prostático y su agresividad en tumores cT1c / Impact of central obesity in the diagnosis and prognosis of cT1c prostate cancer

La obesidad y el sobrepeso afectan al 62,8 por ciento de la población chilena. Esta condición aumenta los niveles de insulina, IGF-1 y otros mediadores inflamatorios asociados al cáncer prostático (CaP). La relación entre CaP y obesidad, utilizando al índice de masa corporal (IMC) como indicador, ha evidenciado resultados inconsistentes. Sin embargo, la obesidad central (OC), determinada por una circunferencia de cintura (CC) mayor de 95 cm, es en la actualidad un mejor predictor de los efectos metabólicos y cardiovasculares de la adiposidad. El objetivo de este estudio fue evaluar la asociación entre OC y CaP. Como objetivo secundario se evaluó los efectos de la OC sobre: volumen prostático (VP), APE, score de Gleason y porcentaje de cáncer en biopsia transrectal (BTR).Materiales y Método: Se diseñó un estudio de casos y controles prospectivo. Se incluyeron todos los pacientes sometidos a BTR, con clasificación cT1c, en dos hospitales de Santiago, entre junio de 2008 y julio de 2009. Se realizó medición de IMC y CC previo a la BTR, según protocolos validados. Se realizaron tests estadísticos bivariados y multivariados, para medir asociaciones brutas y ajustadas entre las variables estudiadas y el resultado histológico de la BTR. Resultados: Se incluyeron 150 pacientes. El promedio de edad fue 63,1 años. El 53,3 por ciento tuvo una CC mayor de 95 cm. Ambos grupos de exposición fueron comparables. Hubo 40,0 por ciento con CaP y, entre ellos, el 40,0 por ciento fue considerado de alto riesgo. No se encontró asociación significativa entre CC y las variables: VP, APE y presencia de cáncer en la biopsia. Sin embargo, en el análisis multivariado la CC se asoció positivamente con el score de Gleason (p= 0,0352) y con el porcentaje total de CaP en la BTR (p= 0,0341). A mayor VP fue menos probable hallar CaP, y la densidad del APE predijo significativamente el 70 por ciento Conclusiones: En este estudio, la CC no fue un factor de riesgo significativo para la...

Obesity and overweight affect 62 percent of the Chilean population. This condition increases insulin levels, IGF-1 levels and other inflammatory mediators associated to prostate cancer (PCa). The relationship between PCa and obesity using the body mass index (BMI) as an indicator, has been inconsistent. However, central obesity (CO), determined by a waist circumference (WC) over 95 cm, is currently a better predictor for the metabolic and cardiovascular effects of adiposity. The objective of this study was to evaluate the association between CO and PCa. As a secondary objective, we evaluated the effects of CO on: prostate volume (PV), serum PSA, Gleason score and percentage of cancer in the transrectal biopsy (TRB).Materials and method: We designed a prospective case control study. All patients submitted to TRB, with cT1c tumors, at 2 hospitals in Santiago between June 2008 and July 2009, were included. Before TRB, BMI and WC were measured, according to standard protocols. Bivariated and multivariated statistical tests were used to measure both raw and adjusted associations between the studied variables and the histologic result of the TRB. Results: The study included 150 patients. Average age was 53.1 years. A WC over 95 cm was found in 53 percent of them. Both groups were comparable. PCa was present in 40 per cent of the subjects; among them, 40 percent had high risk tumors. No significant association was found between WC and the following variables: PV, PSA level and the presence of cancer in the TRB. However, in the multivariate analysis, WC was associated with Gleason score (p =0.0352). Also, the total percentage of PCa in the TRB was associated with WC (p =0.0341). At higher PV, PCa was less frequent and PSA level predicted 70 percent of PCa. Conclusions: In this study, WC was a significant risk factor for the presence of PCa. Nevertheless, a pathologic WC was associated with higher Gleason scores and higher percentage of PCa in the TRB...

Factores pronósticos en carcinoma de células renales: ¿son adecuadas las variables definidas por el actual TNM? / Prognosis factors in renal cells carcinoma: are the variables defined by TNM adequate?

Objetivo: Identificar aquellos factores pronósticos que influyen de manera independiente en la sobrevida y en caso de ser significativo el tamaño de la lesión, determinar cuál es el mejor punto de corte para esta variable. Materiales y métodos: Se revisaron los registros de 420 pacientes con diagnóstico de carcinoma de células renales estudiados entre enero de 1994 y junio de 2004 en dos centros. El análisis de sobrevida se efectuó a través de curvas de Kaplan-Meier. Se realizó estudio univariado y multivariado para determinar qué factores, clínicos e histológicos, tienen un impacto directo en la sobrevida de los pacientes con cáncer renal. El mejor punto de corte para el tamaño tumoral se determinó por medio de curvas ROC. Resultados: La sobrevida global de la serie fue 76,4 por ciento, con un seguimiento promedio de 30,8 meses (DS±24,5). El análisis demostró una tasa de sobrevida de 95,7 por ciento para T1, 58,5 por ciento para T2, 65,2 por ciento, 49,4 por ciento, 35,4 por ciento para T3 a, b y c, respectivamente y 44,4 porciento para T4. El análisis univariado mostró que la edad, al momento del diagnóstico, el valor del hematocrito y VHS preoperatorios, la presencia de fosfatasas alcalinas elevadas y el tamaño de la lesión influyen en la sobrevida (p <0,05). El análisis multivariado reveló que la presencia de fosfatasas alcalinas elevadas, el tamaño, la invasión de la vena renal (p <0,01) y la invasión de la cápsula renal (p <0,05) son variables con significativo valor pronóstico. El mejor punto de corte para el tamaño entregado por la curva ROC fue 6 cm, tanto para recidiva como para muerte por cáncer, alcanzado una sensibilidad de 80,6 por ciento y una especificidad de 68,1 por ciento.Conclusión: La actual etapificación TNM no se correlaciona certeramente con las sobrevidas obtenidas en esta serie de pacientes. En contraste con lo mencionado en la literatura internacional, el grado de Fuhrman, la invasión de la glándula suprarrenal y el tipo histológico...

Uretroplastia de aumento con injerto de mucosa bucal / Increase uretroplasy with grafting of buccal mucous

La patología de la estenosis uretral tiene etiología, el tratamiento varía según su ubicación anatómica, extensión y espongiofibrosis. Los tratamientos previos, como la uretrotomía interna (UI), pueden determinar que una estenosis breve se transforme en compleja, con un detrimento en el éxito de curación. Ante estenosis complejas se requiere realizar una uretroplastia. Se revisa la experiencia de uretroplastia con mucosa oral en 20 pacientes: 9 portadores de estenosis bulbar, 3 de uretra peneana y bulbar, 3 peneana, 4 con balanitis xerótica obliterans (BXO) y una panestenosis. La tasa de éxito global de la serie fue de 80 por ciento (16 de 20 pacientes) con un seguimiento promedio de 13,5 meses. El éxito para la estenosis peneana y bulbar fue de 81 por ciento (13 de 16 pacientes). No hubo recidiva de liquen escleroso en la mucosa bucal. No se registraron complicaciones mayores. La uretroplastia de aumento con mucosa oral es una buena opción para estenosis complejas con baja morbilidad.

Prostatectomía radical en pacientes sometidos a cirugía prostática previa / Radical prostactectomy in patients with previous prostatic surgery

El objetivo del presente trabajo fue evaluar si existen diferencias significativas entre los pacientes sometidos a PR teniendo un procedimiento quirúrgico previo sobre esta glándula. Pacientes y métodos: Se realizó un estudio retrospectivo de los pacientes sometidos a PR en quienes existió una cirugía prostática previa por patología benigna. Los datos fueron obtenidos de la revisión de la base de datos de nuestro departamento, considerando el período de mayo de 1999 hasta mayo de 2004. Resultados: En el período analizado se realizaron 54 PR, en pacientes con cirugía prostática previa (7,4 por ciento del total de pacientes sometidos a PR), con un promedio de edad de 68 años. Ocho pacientes fueron sometidos a cirugía abierta (3 operación de Millin, 5 transvesicales), el resto de los pacientes se realizó resección transuretral. El tiempo promedio entre la cirugía previa y la PR fue de 5,3 años. El 18,8 por ciento tuvo score de Gleason >=8, el 77 por ciento score de 7 y el 4,1 por ciento score <=6. El APE promedio fue de 13,2 ng/dl. El volumen tumoral alcanzó los 6,48 cc en la pieza patológica. La subetapificación clínico patológica llegó al 73,9 por ciento. Las lesiones órgano confinadas fueron 69,96 por ciento de la muestra. No hubo mortalidad operatoria. El 26,6 por ciento de los pacientes requirió transfusión de glóbulos rojos. En 73,4 por ciento de nuestra serie la cirugía no superó las tres horas. De la morbilidad derivada del procedimiento destacan 3 filtraciones de la anastomosis y 3 pacientes que presentaron estenosis de la anastomosis. La continencia alcanza al 90,3 por ciento. Discusión: En comparación con resultados publicados previamente por nuestro servicio y por otros centros en relación a PR, esta serie se diferencia en cuanto a, una cifra menor de APE promedio, mayor porcentaje de casos con score de Gleason 7 y de pacientes con lesiones órgano confinadas. El tiempo operatorio promedio es similar a otros reportes. No existen diferencias en cuanto a transfusión ni complicaciones.

[Nutrient content and health effects of nuts]. / Composición nutritiva y efectos sobre la salud de los frutos secos.

Nuts are foods with a high energy density, due in part to its small water content. They also present a low saturated fat content (<7%) but a high unsaturated fat contribution (40-60%). They represent one of the richest sources of dietary fiber, which is basically of the insoluble type. The effects of nut intake on health have been widely studied. Several prospective epidemiological studies performed on large cohorts have consistently shown that regular consumption of small amounts of nuts is negatively related to the risk of cardiovascular disease and to the risk of cardiovascular or all-cause mortality. From these studies can be concluded that regular consumption of small amounts of nuts leads to a 30-50% reduction in the risk of cardiovascular disease. Additionally, intervention studies have shown a positive effect of nut intake on lipid profile with significant reductions in total and LDL cholesterol levels and small or null effects on the HDL fraction. More recently, some studies have focused on the effect of nuts on body weight. At present, no evidences support a detrimental effect of nut consumption on body weight. On the contrary some weight loss studies suggest a beneficial effect of nut intake on body weight regulation.

Composición nutritiva y efectos sobre la salud de los frutos secos / Nutrient content and health effects of nuts

Los frutos secos son alimentos caracterizados por una alta densidad energética debida en parte a su escaso contenido hídrico. Además, presentan un bajo contenido en grasa saturada (<7 por ciento) y un elevado aporte de grasa insaturada (40-60 por ciento). Constituyen también una de las fuentes más ricas de fibra dietética, fundamentalmente insoluble. Se ha estudiado ampliamente cuales son los efectos que la ingestión de frutos secos tiene sobre la salud. Diversos estudios epidemiológicos prospectivos realizados sobre amplias cohortes han mostrado consistentemente una relación negativa entre el consumo regular de pequeñas cantidades de frutos secos y el riesgo de enfermedad cardiovascular o el riesgo de mortalidad de origen cardiovascular y de mortalidad por todas las causas. El análisis de estos estudios refleja que el consumo regular de pequeñas cantidades de frutos secos reduce el riesgo de enfermedad cardiovascular en un 30-50 por ciento. Los estudios de intervención demuestran que la toma regular de suplementos de frutos secos mejora el perfil lipídico, reduciendo significativamente los niveles de colesterol total y colesterol LDL con escaso o nulo efecto sobre las HDL. El efecto de los frutos secos sobre el peso corporal ha sido también recientemente estudiado. Hasta el momento no existen evidencias de un aumento de peso corporal asociado al consumo de estos alimentos y, sin embargo, algunos estudios de pérdida ponderal sugieren un posible efecto beneficioso en la regulación del peso corporal

Pteridine concentrations differ between insectary-reared and field-collected Anopheles albimanus mosquitoes of the same physiological age.

Biopterin, isoxanthopterin and 6-pterincarboxylic acid were identified in the head of the malaria vector mosquito Anopheles albimanus Weidemann (Diptera: Culicidae) by HPLC. Total pteridine concentrations (TPC) were estimated in heads, body parts (BP: abdomen, legs and wings) and whole bodies of insectary-reared and field-collected females, by spectrofluorometry, to investigate whether they could be used for age determination. Pteridine concentrations diminished with age in both mosquito groups. TPC correlated with chronological age in insectary-reared sugar-fed females (heads: r2 = 0.35, BP: r2 = 0.34, P < 0.001), but lower correlation occurred in blood-fed females (heads: r2 = 0.22, BP: r2 = 0.27). TPC differed among females of the same age fed with blood at different times (P < 0.05), indicating that bloodmeals modify the diminution rate of pteridines with age. Nevertheless, a polynomial significant correlation was documented for TPC and the number of ovipositions (heads: r2 = 0.24, BP: r2 = 0.27, whole body: r2 = 0.52, P < 0.001) in insectary-reared mosquitoes. This correlation was lower in field-collected mosquitoes (heads: r2 = 0.14, BP: r2 = 0.10, P < 0.05), which showed a remarkable pteridine increase in one-parous females. The correlation of TPC in whole body with physiological age was much less (r2 = 0.03). These observations indicate that TPC determination by spectrofluorometry is not a reliable method to estimate the age of An. albimanus females from the feral population.

Drug Susceptibility of Mycobacterium tuberculosisThrough the Mycolic Acid Index.

The methods accepted to determine antimicrobial drug susceptibility of mycobacteria are based on the determination of the microorganisms' growth on solid or liquid medium containing a specified concentration of a single drug.

Mg, Mn, and Co ions enhance the formation of Entamoeba histolytica cyst-like structures resistant to sodium dodecyl sulfate.

BACKGROUND: Entamoeba histolytica forms cyst-like structures (CLS) in PEHPS but not in TYS-33 medium. Sodium dodecyl sulfate [(SDS (0.1%)] dissolves most of them in 10 min, but not natural cysts. Chitin is responsible mainly for cyst wall resistance. Its synthesis depends on Mg(2)+, Mn(2)+, or Co(2)+, whose action is interactive. With the aid of the Simplex method, we analyzed the effect of 20 blends of these cations to find the one that, when added to PEHPS, produced the highest proportion of CLS resistant to 1% SDS (RCLS). METHODS: The concentration of Mg(2)+, Mn(2)+, and Co(2)+ was determined in PEHPS and TYI-S-33 with a flame atomic absorption spectrometer. The proportion of RCLS produced in PEHPS with each ion blend was tested. The CLS and RCLS affinity to fluorescein wheat germ agglutinin (WGA/FITC), which binds chitin, was determined. RESULTS: PEHPS contained a similar concentration of Co(2)+ (0.52 microM) and 3.4 and 1.6 times more Mg(2)+ (798 microM) and Mn(2)+ (3.15 microM) than TYI-S-33, respectively. The proportion of RCLS increased gradually in PEHPS until reaching 3.6 +/- 1.43% with MgCl(2) 1.22 mM, MnCl(2) 14.44 mM, and CoCl(2) 19.44 mM (ion blend No. 20). Both CLS and RCLS bound WGA/FITC. The RCLS formed in the presence of ion blend No. 20 appeared wrinkled. CONCLUSIONS: Mg(2)+, Mn(2)+, and Co(2)+ enhanced the ability of PEHPS to form RCLS, possibly because these ions stimulated their chitin synthesis. Although ion blend No. 20 produced the highest proportion of RCLS, this high ion concentration may be toxic for encysting amebas.

Determination of drug susceptibility of Mycobacterium tuberculosis through mycolic acid analysis.

In the present work a rapid method to determine the susceptibility of Mycobacterium tuberculosis to isoniazid and streptomycin by determining levels of mycolic acids by high-performance liquid chromatography (HPLC) was developed. Mycobacterial growth kinetics in the presence and absence of antituberculosis drugs was characterized by evaluating the total area corresponding to mycolic acid peaks (TAMA). Results show a linear relationship between the logarithm of CFU per milliliter and TAMA and show that it is possible to detect growth inhibition of M. tuberculosis in the presence of isoniazid or streptomycin by using HPLC in 3 and 4 days, respectively.

[Pharmacokinetic design for the preclinical phase. Application to the study of an anthracenone]. / Diseño farmacocinético de fase preclínica. Aplicación al estudio de una antracenona.

T-514 is a toxic substance of Karwinskia humboldtiana which has been described as a possible anticancer agent. An animal model (New Zeland white rabbit) was selected for pharmacokinetic studies that would allow the performance of surgical techniques to catheterize central vessels in order to obtain blood samples at short time intervals. A nonlinear regression analysis method was used to fit the plasmatic concentration data to a multiexponential mathematical function; a computer program based on Marquant's iterating algorithm was used to fit the experimental curves. In the present work we show the advantage of introducing two catheters of different diameters in the jugular vein using modifications of the Seldinger and Braunüle techniques: a catheter of small diameter (18 G) is used to introduce the drug and a larger one (16 G) to sample at different times. The larger diameter catheter facilitates a rapid sampling of blood (two mL/s) which is essential to determine the initial phase of the distribution process (alpha phase). The behavior of T-514 corresponded to a two-compartment model with a biexponential equation C = 0.35 e-0.13(t-2) + 0.17 e-0.03(t-2).