CAPTURA. Repositorio Academico de la Universidad de Chile
(5.176 recursos)
Captura almacena y conserva la producción de conocimiento generado por docentes e investigadores de la Universidad de Chile, y la hace visible desde los portales académicos internacionales.
Mostrando recursos 1 - 20 de 123
1.
Prevalence of type 2 diabetes and obesity in two Chilean aboriginal populations living in urban zones - Carrasco Piña, Elena; Pérez Bravo, Francisco; Angel Badillo, Bárbara; Albala Brevis, Cecilia; Santos, José Luis; Larenas Y., Gladys; Montalvo V., Domingo
Background: The prevalence of cardiovascular risk factors is increasing in aboriginal populations in Chile. Aim: To study the prevalence of obesity, type 2 diabetes and serum lipids in two aboriginal populations, Mapuche and Aymara, that were transferred from a rural to a urban environment. Subjects and Methods: Two groups of subjects over 20 years were analyzed, Mapuche and Aymara. The Mapuche group was formed by 42 men and 105 women, living in four urban communities of Santiago, and an Aymara group formed by 42 men and 118 women, living in Arica, in Northern Chile. Anthropometric measurements, blood pressure, lipid profile,...
2.
Bioavailability of elemental iron powder in white wheat bread - Walter, Tomas; Pizarro, Fernando; Abrams, Steven A.; Boy, Erick
Objective: Iron fortification of wheat flour is widely used. In most cases, elemental iron powders are utilized as fortificants due to their lower cost and few, if any, sensory problems. However, their bioavailability is unknown. We aimed to measure the bioavailability of H-2-reduced elemental iron powder in white wheat bread made from 72% extraction flour.
Design: A stable isotope of H-2-reduced iron powder (mean particle size 15 mum) was used as fortificant in bread prepared from unfortified wheat flour. In all, 12 5- to 7-y-old children were fed bread with 4 mg of H-2-reduced Fe-58/100 g of flour. The next day...
3.
EGF receptor transactivation by urokinase receptor stimulus through a mechanism involving Src and matrix metalloproteinases - Guerrero, Javier; Santibáñez, Juan Francisco; González, Alfonso; Martínez, Jorge
Urokinase-type plasminogen activator receptor (uPAR) and epidermal growth factor receptor (EGFR) are ubiquitous receptors involved in the control of a variety of cellular processes frequently found altered in cancer cells. The EGFR has been recently described to play a transduction role of uPAR stimuli, mediating uPA-induced proliferation in highly malignant cells that overexpress uPAR. In the present work, we found for the first time that uPAR stimulation with the amino-terminal fragment (ATF) of urokinase devoid of proteolytic activity transactivates the EGFR in mammary MCF-7 cells through a mechanism involving Src and a metalloproteinase, as indicated by its sensitivity to selected...
4.
Folic acid fortification of wheat flour: Chile - Hertrampf, Eva; Cortés, Fanny
Neural tube defects (open spina bifida, anencephaly, and encephalocele) represent the first congenital malformations to be preventable through public health measures such as supplementation and/or food fortification with folic acid. In Chile, starting in January 2000, the Chilean Ministry of Health legislated to add folic acid to wheat flour (2.2 mg/kg) to reduce the risk of NTDs. This policy resulted in an estimated mean additional supply of 427 mu g/d in significant increases in serum folate and red cell folate of 3.8 and 2.4-fold, respectively, in women of fertile age, one year after fortification. The impact on the rate of...
5.
Validation of a screening test for age associated cognitive impairment, in Chile - Quiroga, Pilar; Albala Brevis, Cecilia; Klaasen, Gonzalo
Background: The real prevalence of dementia in a given population must be determined through prevalence studies, using validated screening tests. Aim: To validate and determine cutoff points for a cognitive impairment screening test composed by the Folstein Mini Mental State Examination (MMSE) and Pfeffer Functional Activities Questionnaire (PFAQ). Material and methods: Validation of the diagnostic test in a sample of 100 subjects over 65 years old (85 from the project "Age associated dementias" and 15 with a confirmed diagnosis of dementia). All were subjected to a complete neuropsychological test by a trained neurologist, that constituted the "gold standard" the diagnosis...
6.
Estado nutricional y resistencia aeróbica en escolares de educación básica: línea base de un proyecto de promoción de la salud - Kain B., Juliana; Olivares C., Sonia; Romo M., Marcela; Leyton D., Bárbara; Vio D., Fernando; Cerda R., Ricardo; González P., Rosa; Giadalah Astudillo, Francisco Antonio; Albala Brevis, Cecilia
Background: The Chilean Ministry of Health has developed a health promotion program called "Vida Chile" whose aim is to target risk factors for chronic diseases. To achieve this, school-based initiatives in nutrition and physical activity have been implemented. The evaluation of these initiatives includes a baseline assessment of these two variables.
Aim: Baseline assessment of the nutritional status and aerobic capacity of elementary school children (1st to 8th grade).
Material and methods: Children from seven public schools were studied. Weight, height, triceps skinfold thickness and waist circumference were measured. To test the aerobic capacity, the 20-m Shuttle Run Test (Navette) was...
7.
Inequalities in health. Adult mortality in communities of Metropolitan Santiago - Sánchez R., Hugo; Albala Brevis, Cecilia
Background: In the last decade, Chile achieve a significant reduction in poverty, however income distribution still shows inequalities. The richest 10% of the population perceived 46% of total income. Aim: To study the relationship between territorial socioeconomic seqregation and adult mortality in the Metropolitan area of Santiago de Chile. Material and methods: Data fro the 34 districts of Metropolitan Santiago de Chile. Adjusted community mortality rates, during 2000, among adults aged 20 years or more, including specific rates per sex and age group, were analyzed. Results: There was a negative correlation between income and mortality, specially among men (rS -0.42...
8.
Iron, zinc, and copper: Contents in common Chilean foods,and daily intakes in Santiago, Chile - Olivares, Manuel; Pizarro, Fernando; Pablo, Saturnino de; Araya Q., Magdalena; Uauy, Ricardo
OBJECTIVES: We determined the iron (Fe), zinc (Zn), and copper (Cu) contents of common Chilean foods and assessed the intakes of these elements in a population living in Santiago, Chile.
METHODS: We selected foods most consumed by a Chilean population (n = 108). We performed wet digestion of the sample by using nitric, perchloric, and sulfuric acids. Fe, Zn, and Cu were determined by atomic absorption spectrophotometry. Fe, Zn, and Cu intakes were evaluated by a dietary survey (24-h recall questionnaire for 4 non-consecutive days) in a representative sample of the population of Santiago, Chile (n = 252 subjects).
RESULTS: Fe...
9.
Vitamin D receptor polymorphism and susceptibility to type 1 diabetes in chilean subjects: A case-parent study - Angel Badillo, Bárbara; Santos, José Luis; Carrasco Piña, Elena; Albala Brevis, Cecilia; Pérez Bravo, Francisco
Several reports have found a relation between polymorphisms of the vitamin D receptor gene (VDR) and the development of type I diabetes. We have examined the association of three VDR polymorphism with type I diabetes in 59 Chilean case-parents trios. Genotyping for Bsml, Apal and Taq1 polymorphism were performed. Transmission/ disequilbrium tests were used to assess gene-disease associations through the evaluation of allelic transmission to affected offspring. Non-significant increased transmissions of B allele (probability of transmission = 52.5%, p = 0.69), A allele (probability of transmission = 58.4%, p = 0.17) and T allele (probability of transmission = 52.0%, p...
10.
Community-based randomized double-blind study of gastrointestinal effects and copper exposure in drinking water - Araya Q., Magdalena; Olivares, Manuel; Pizarro, Fernando; Llanos, Adolfo; Figueroa, Guillermo; Uauy, Ricardo
We assessed gastrointestinal effects in 1,365 adults exposed to either < 0.01 (controls), 2, 4, or 6 mg copper/L of drinking water for 2 months in a randomized, double-blind community-based study. The risk of symptoms increased with increasing Cu exposure and decreased with time. The best model by counting-process analysis included Cu concentration and sex. The risk of symptoms remained significantly higher in women than in men during weeks 1-4 for all concentrations tested; at week I comparison with the < 0.01-mg/L group showed that differences became significant in women at 4 mg/L [relative risk (RR) = 1.53; 95% confidence...
11.
Intracellular localization of Arabidopsis sulfurtransferases - Bauer, Michael; Dietrich, Christof; Nowak, Katharina; Sierralta, Walter; Papenbrock, Jutta
Sulfurtransferases (Str) comprise a group of enzymes widely distributed in archaea, eubacteria, and eukaryota which catalyze the transfer of a sulfur atom from suitable sulfur donors to nucleophilic sulfur acceptors. In all organisms analyzed to date, small gene families encoding Str proteins have been identified. The gene products were localized to different compartments of the cells. Our interest concerns the localization of Str proteins encoded in the nuclear genome of Arabidopsis. Computer-based prediction methods revealed localization in different compartments of the cell for six putative AtStrs. Several methods were used to determine the localization of the AtStr proteins experimentally. For...
12.
Niveles plasmáticos de citoquinas IL-1ß, IL2 e IL-4 en niños diabéticos tipo 1 de diagnóstico reciente y su asociación con anticuerpos ß pancreáticos - Pérez Bravo, Francisco; Oyarzún A., Amaya; Carrasco Piña, Elena; Angel Badillo, Bárbara; Albala Brevis, Cecilia; Santos, José Luis
Background: Type 1 diabetes is an organ specific autoimmune disease whose incidence is increasing worldwide. A functional imbalance in cytokine production resulting in dominance of T helper (Th1) over Th2-type response has been suggested to play a critical role in the pathogenesis of type 1 diabetes. Aim: To measure serum concentrations of interleukin (IL)-1 beta, IL-2 and IL-4 in children with recently diagnosed type 1 diabetes and to evaluate the autoimmune response measuring glutamic acid decarboxylase (GAD65) and tyrosine phosphatase like (IA-2) autoantibodies. Patients and Methods: 120 diabetic children and 118 age and gender matched control children, were recruited for...
13.
The mechanisms for regulating absorption of Fe bis-glycine chelate and Fe-ascorbate in Caco-2 cells are similar - Mazariegos, Dora Inés; Pizarro, Fernando; Olivares, Manuel; Núñez, Marco T.; Arredondo, Miguel
Inorganic iron (Fe) absorption from the diet is controlled mainly in the intestinal tract where apical Fe uptake is inversely related to the Fe content in the enterocyte. Iron bis-glycine chelate is an iron compound that may be absorbed by a mechanism different from the regulated nonheme Fe pathway. Because Fe bis-glycine chelate is used increasingly as an Fe fortificant in foods, the critical question is whether this compound is a safe Fe supplement. We compared apical Fe uptake and transepithelial transport offered either as Fe-59 bis-glycine chelate or a Fe-59-ascorbate (Fe-AA) complex in Caco-2 cells, as a model of...
14.
Sex and ceruloplasmin modulate the response to copper exposure in healthy individuals - Méndez, Marco; Araya Q., Magdalena; Olivares, Manuel; Pizarro, Fernando; González, Mauricio
Previous studies indicated that sex might influence the response to copper exposure. Cenaloplasmin (Cp) is an indicator of Cu status, but it is not clear whether and how it reflects changes of Cu status among healthy individuals. In this study, 82 apparently healthy women and men were chosen from 800 individuals because their Cp values belonged to the higher and lower 10% of the group Cp distribution curve. Before and after receiving a supplement of 10 mg Cu/day (upper limit of daily intake) for 2 months, we performed blood and urinary biochemical measurement of potential Cu markers. We used principal...
15.
The association between HLA DQ genetic polymorphism and type 1 diabetes in a case-parent study conducted in an admixed population - Mimbacas, Adriana; Pérez Bravo, Fernando; Santos, José Luis; Pisciottano, Carmen; Grignola, Rosario; Javiel, Gerardo; Jorge, Ana María; Cardoso, Horacio
Susceptibility to the type 1 diabetes is genetically controlled and there is an increased risk associated with the presence of some specific alleles of the human leukocyte antigens class II loci (DQA1 and DQB1 genes). The purpose of this study is to evaluate the association between type 1 diabetes and HLA DQ alleles using case-parents trios in the admixed population of Uruguay composed by a mixture of Caucasian, Amerindian and Negroid populations. DQA1 and DQB1 genotyping was performed by polimerase chain reaction followed by oligospecific probes hybridization in 51 case-parents trios. The transmission disequilibrium test was used for detecting differential...
16.
Insulin secretion in women who have polycystic ovary syndrome and carry the Gly972Arg variant of insulin receptor, substrate-1 in response to a high-glycemic or low-glycemic carbohydrate load - Sir-Petermann, Teresa; Angel Badillo, Bárbara; Maliqueo, Manuel; Santos, José Luis; Riesco, María Virginia; Toloza, Henry; Pérez Bravo, Francisco
OBJECTIVE: We evaluated metabolic parameters in Chilean women with polycystic ovary syndrome (PCOS) who were carriers and non-carriers of the glycine-to-arginine substitution at codon 972 (Gly972Arg) variant of insulin receptor substrate-1 and to assess insulin response after oral high- and low-glycemic loads
METHODS: In 146 women with PCOS and 97 healthy women (HW), Gly972Arg genotypes were obtained by polymerase chain reaction, and an oral glucose tolerance test was performed with glucose and insulin measurements. An insulinogenic index, a homeostasis model assessment for insulin resistance, and whole-body insulin sensitivity index (composite) were calculated. Eight carriers and eight non-carriers (four PCOS and...
17.
The poor bioavailability of elemental iron in corn masa flour is not affected by disodium EDTA - Walter, Tomas; Pizarro, Fernando; Boy, Erick; Abrams, Steven A.
The most sustainable way to eradicate iron deficiency is through food fortification. Elemental iron powders are commonly utilized as fortificants due to their low cost and few sensory problems. However, their bioavailability is unknown. Our goals were to measure the bioavailability of elemental iron in Mexican style corn masa flour tortillas and to evaluate the effects of Na(2)EDTA. We used a stable isotope of H-2-reduced iron powder, with and without Na(2)EDTA in tortillas prepared with corn masa flour. Two groups of 5- to 7-y-old children (n = 12/group) were fed tortillas to which was added 3 mg/100 g of H-2-reduced...
19.
Identification of genes expressed during Drosophila melanogaster gastrulation by using subtractive hybridization - González-Aguero, Mauricio; Zuñiga, Alejandro; Pottstock, Hans; Pozo, Talía del; González, Mauricio; Cambiazo, Verónica
A subtractive hybridization approach was used to identify genes that are expressed at the beginning of gastrulation. We used tester DNA complimentary to RNA (cDNA) prepared from stages 6-7 embryos (gastrula) and excess driver cDNA from stages 2-4 embryos (syncytial blastoderm) to generate a gastrula-subtracted cDNA library. A reverse Northern blot procedure used to analyze 105 subtracted clones showed that 65% had a level of expression at least 2.5-fold higher in stages 6-7 versus stages 2-4 embryos. We determined the nucleotide sequence of these clones and identified 49 individual sequences, including 33 previously uncharacterized genes. We verified the level of...
20.
Overexpression of RhoA-GTP induces activation of the Epidermal Growth Factor Receptor, dephosphorylation of focal adhesion kinase and increased motility in breast cancer cells - Cáceres, Mónica; Guerrero, Javier; Martínez, Jorge
Rho GTPases are overexpressed in human tumors and are involved in a variety of cellular processes such as organization of the actin cytoskeleton, cell-cell contact and malignant transformation. EGFR activation plays a key role in the acquisition of motile properties in carcinoma cells, and it has been proposed that downregulation of FAK activity is one of its most relevant consequences. In the present study, using mammary MCF-7 cells, we demonstrated that overexpression of the active form of the small GTPase RhoA induced the activation of EGFR by a phenomenon that depends on the activity of a metalloproteinase (MMP), which presumably...
1.
