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Search Results: 1 - 10 of 57977 matches for " Maldonado-Hernández Jorge "
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Association between Metabolic Syndrome and Erythrocyte Fatty Acid Profile in Mexican Adolescents: A Trans Fatty Acid Approach  [PDF]
Martínez-Razo Gabriel, Martínez-Basila Azucena, Salas-Fernández Alejandra, Maldonado-Hernández Jorge
Food and Nutrition Sciences (FNS) , 2013, DOI: 10.4236/fns.2013.49A1009
Abstract:

The type of fat consumed in the Mexican diet could predispose to the development of Metabolic Syndrome (MS) which has been associated with an increased risk to develop cardiovascular disease and type 2 diabetes mellitus. Our study included adolescents between 12 and 16 years of age, divided in two groups: Control Group (n = 31) and MS Group (n = 44). Waist circumference, blood pressure, fasting glucose, triglycerides, and HDL-cholesterol were determined. Erythrocytes’ fatty acids methyl esthers were quantified using gas chromatography with ionized flame detector. We identified 16 fatty acids (FA) with chain lengths from C12 to C24, with emphasis in four trans FA (TFA) isomers: vaccenic (C18:1n7t), elaidic (C18:1n9t), linoelaidic (C18:2n6t), and conjugated linoelaidic acids (C18:2n7t). MS Group had a less proportion of: myristic (C14), palmitoleic (C16:1), C18:1n7t, and linoleic acids (C18:2); and a higher one of C18:1n9t, C18:2n7t, and nervonic acids (C24:1) when compared to the control group. C24:1 and C18:1n9t had a significant positive association with MS (OR = 14.17 and OR = 12.94, respectively); whereas C14 (OR = 0.14), C18:1n7t (OR = 0.14), and C18:2 (OR = 0.22) appear to have a protective effect against the disease. The proportion of specific FAs in erythrocytes’ membranes differs between adolescents with MS and healthy controls; these FA not only showed a strong association with MS, but also correlated with most of its individual components. Interestingly, TFA displayed an antagonic behavior; while C18:1n9t had a strong association with MS, apparently C18:1n7t confers a protective effect; these results suggest that analyzing each TFA separately will constitute a more accurate approach to determine the role of TFAs in the pathogenesis of MS or other related metabolic disorders.

Assessment of Lipid Quality and Composition of Commercial Infant Milk Formulas in Mexico: Emphasis on Trans Fatty Acid Isomers  [PDF]
Ayala-Moreno María del Rosario, Fernández-Callejas José María Salvador, Maldonado-Hernández Jorge
Food and Nutrition Sciences (FNS) , 2016, DOI: 10.4236/fns.2016.74029
Abstract: Objective: To assess the lipid quality focusing on trans fatty acids (TFA) content of standardized milk formulas marketed in Mexico for infants aged from 0 to 36 months. Material and Methods: A total of 27 infant formulas from eight different leading brands were analyzed. Nine of them belonged to stage 1 (age < 6 months), nine to stage 2 (age 6 to 12 months) and eight to stage 3 (age > 12 months). Acquired products were treated by duplicate for extraction of total lipid content with the modified Folch method before their expiration date. Fatty acids were esterified in an alkaline medium followed by an acid-catalyzed esterification. Analysis was performed on a gas chromatograph (5890 Series II; Hewlett-Packard, USA) with a flame ionization detector. Results: Thirty-four fatty acids (C8 to C22) were identified. Most products complied with ESPHAGAN compositional requirements. Only one product exceeded the suggested limit (>3%) for TFA. Long chain polyunsaturated fatty acids (LC-PUFAs) content was consistently meager (≈78%), with low amounts of arachidonic (<0.35%) and docosahexaenoic acids (<0.2%).Conclusion: Most milk formulas complied with ESPHAGAN global recommendations. The content of TFA and LC-PUFAs was scarce in the majority of samples.
Cultivo del coral cuerno de alce Acropora palmata en un sistema recirculado utilizando agua de mar sintética
Hernández-Zárate,Galdy; Lango-Reynoso,Fabiola; Casta?eda-Chávez,María del Refugio; Zamora-Castro,Jorge E; Maldonado-Hernández,Juan Raymundo;
Revista de biología marina y oceanografía , 2011, DOI: 10.4067/S0718-19572011000300017
Abstract: this study assessed the survival of acropora palmata fragments under controlled experimental conditions over a period of four months in a recirculating artificial seawater system. the coral fragments (5-9 cm long) were fixed in aragocrete and placed in an aquarium under a photoperiod of 12 h light: 12 h dark, using 150 w lamps (10000 k). the survival rate was 58%. fragment mortality occurred mostly during the first month, which was associated to the process of bleaching stress as a result of fragmentation. these results showed that the conditioning in captivity of a. palmata using artificial seawater has potential as a viable tool to help the conservation of this species.
Métodos diagnósticos de la resistencia a la insulina en la población pediátrica
Martínez Basila, Azucena;Maldonado Hernández, Jorge;López Alarcón, Mardia;
Boletín médico del Hospital Infantil de México , 2011,
Abstract: obesity is the main risk factor for insulin resistance (ir) in the pediatric population. ir represents a link between obesity and other metabolic complications such as type 2 diabetes mellitus (t2dm) and cardiovascular disease (cvd). therefore, accurate diagnosis and early intervention may reduce the incidence of t2dm and cvd in at-risk individuals. in this study we describe the techniques used to assess insulin sensitivity in pediatric populations. we also describe in detail three diagnostic tests: the glucose clamp technique, which represents the gold standard to determine tissue insulin sensitivity and insulin secretion; homa and quicki, which are indexes obtained from fasting glucose and insulin concentrations; and isi-composite, obtained from an oral glucose tolerance test, which provides additional information on glucose metabolism after an oral glucose load. in conclusion, the glucose clamp technique is an invasive procedure that is diffcult to use in routine clinical settings. because the cut-off points to diagnose ir with values derived from isi-composite have not been established for pediatric populations, homa and quicki, despite their lack of precision, remain the most used in clinical practice.
Negro Guanajuato, nueva variedad de frijol para el Centro de México
Acosta Gallegos, Jorge Alberto;Mendoza Hernández, Francisco Manuel;Aguilar Garzón, Bismarck;Esquivel Esquivel, Gilberto;Rodríguez Guerra, Raúl;Guzmán Maldonado, Salvador Horacio;
Agricultura técnica en México , 2008,
Abstract: negro guanajuato is a new bean cultivar developed by the bean program of the nacional research institute for forestry, agriculture and livestock (inifap) at the bajio experimental station, celaya, guanajuato. negro guanajuato is of indeterminate growth habit, type iiia, disease resistant and a 100-seeds weight that varies between 17 and 21 g. it has shown high yield potential under irrigated and rainfed conditions at the bajio region of guanajuato and can also be grown in the states of puebla and mexico. in mattson type cookers, the seed of negro guanajuato has displayed cooking times from 50 to 65 min and protein content between 21 and 23.6%.
Niveles de material particulado en colegios distritales ubicados en vías con alto tráfico vehicular en la ciudad de Bogotá: estudio piloto
Franco,Juan Felipe; Yesid Rojas,Néstor; Sarmiento,Olga Lucía; Hernández,Luis Jorge; Zapata,Elizabeth; Maldonado,Andrea; Matiz,Leonardo; Behrent,Eduardo;
Revista Facultad de Ingeniería Universidad de Antioquia , 2009,
Abstract: a pilot study, in which we conducted inhalable particulate matter (pm10) measurements in four public elementary schools in bogotá, is presented. three of these schools are located alongside major urban roads with different types of public transportation. the remainder school is located alongside a rural road. pm10 measurements were carried out using both gravimetric and real time techniques. average pm10 concentrations found in the schools ranged from 55 ug m-3 to 91 ug m-3. these pollutant concentrations are above the world health organization reference values. significant differences in pm10 concentrations were observed between the schools located in urban roads and the school located in the semi-rural area. the present work corresponds to the base line results of a longitudinal study that is still being conducted. these results demonstrate the importance of continuing developing research aimed at characterizing the range of atmospheric pollutants at major city roads environs in bogota.
Methane production by treating vinasses from hydrous ethanol using a modified UASB reactor
Espa?a-Gamboa Elda I,Mijangos-Cortés Javier O,Hernández-Zárate Galdy,Maldonado Jorge A Domínguez
Biotechnology for Biofuels , 2012, DOI: 10.1186/1754-6834-5-82
Abstract: Background A modified laboratory-scale upflow anaerobic sludge blanket (UASB) reactor was used to obtain methane by treating hydrous ethanol vinasse. Vinasses or stillage are waste materials with high organic loads, and a complex composition resulting from the process of alcohol distillation. They must initially be treated with anaerobic processes due to their high organic loads. Vinasses can be considered multipurpose waste for energy recovery and once treated they can be used in agriculture without the risk of polluting soil, underground water or crops. In this sense, treatment of vinasse combines the elimination of organic waste with the formation of methane. Biogas is considered as a promising renewable energy source. The aim of this study was to determine the optimum organic loading rate for operating a modified UASB reactor to treat vinasse generated in the production of hydrous ethanol from sugar cane molasses. Results The study showed that chemical oxygen demand (COD) removal efficiency was 69% at an optimum organic loading rate (OLR) of 17.05 kg COD/m3-day, achieving a methane yield of 0.263 m3/kg CODadded and a biogas methane content of 84%. During this stage, effluent characterization presented lower values than the vinasse, except for potassium, sulfide and ammonia nitrogen. On the other hand, primers used to amplify the 16S-rDNA genes for the domains Archaea and Bacteria showed the presence of microorganisms which favor methane production at the optimum organic loading rate. Conclusions The modified UASB reactor proposed in this study provided a successful treatment of the vinasse obtained from hydrous ethanol production. Methanogen groups (Methanobacteriales and Methanosarcinales) detected by PCR during operational optimum OLR of the modified UASB reactor, favored methane production.
Memorias de un sanatorio antituberculoso
Maldonado,Héctor; Hernández,Mario;
Biomédica , 2004,
Abstract: memories of an antituberculous sanatorium a summary of the existence of the hospital san carlos in bogotá as an antituberculous sanatorium is presented. its origins, architectonic aspects of its building, the criteria with which it was equipped with state of the art scientific equipment and elements and the excellent facilities for attention of inpatients during their prolonged hospital stay are presented. the life of a sanatorium in the pre-antibiotic era, the changes in its routine brought upon by the introduction of effective anti-tb drugs as well as the evolution of treatments which eventually led to the disappearance of sanatoriums, with all its traumatic effects on the hospitals which had been specifically built for this purpose, are described. the contributions made by the hospital to the different medical and surgical aspects of tb management and to the introduction of effective short course ambulatory treatment regimens are also referred. mention is also given to the rescue of this memory, an important part of the health sciences museum which will shortly open in bogotá
Desarrollo y Situación Actual de la Bioética en México. Desarrollo y Situación Actual de la Bioética en México
Jorge Hernández Arriaga
Acta Universitaria , 2012,
Abstract: An overview on bioethics and the development of institutions devoted to the study of bioethics in Mexico, is presented, in particular the Centro de Investigaciones en Bioética de la Universidad de Guanajuato (CIBUG). Also, academic activities that support this topic are summarized, such as teaching of bioethics, biomedical research, National and International Congresses, Journals and Books that have contributed to the development of bioethics in Mexico. Se presenta una panorámica de la bioética y el desarrollo de las instituciones que la estudian en México, en particular el Centro de Investigaciones en Bioética de la Universidad de Guanajuato (CIBUG). Asimismo, se revisan las actividades académicas que se realizan como ense anza de la bioética, investigación biomédica y la realización de productos y eventos académicos, tales como Congresos, Revistas y Libros, que han contribuído al desarrollo de la bioética en México.
Trihalomethanes in Comerio Drinking Water and Their Reduction by Nanostructured Materials  [PDF]
Jorge Hernández Bourdon, Francisco Márquez Linares
Soft Nanoscience Letters (SNL) , 2014, DOI: 10.4236/snl.2014.42005
Abstract: The formation of disinfection by-products (DBPs) during chlorination of drinking water is an issue which has drawn significant scientific attention due to the possible adverse effects that these compounds have on human health and the formation of another DBPs. Factors that affect the formation of DBPs include: chlorine dose and residue, contact time, temperature, pH and natural organic matter (NOM). The most frequently detected DBPs in drinking water are trihalomethanes (THMs) and haloacetic acids (HAAs). The MCLs are standards established by the United States Environmental Protection Agency (USEPA) for drinking water quality established in Stage 1, Disinfectants and Disinfection Byproducts Rule (DBPR), and they limit the amount of potentially hazardous substances that are allowed in drinking water. The water quality data for THMs were evaluated in the Puerto Rico Aqueduct and Sewer Authority (PRASA). During this evaluation, the THMs exceeded the maximum contamination limit (MCLs) for the Comerio Water Treatment Plant (CWTP). USEPA classified the THMs as Group B2 carcinogens (shown to cause cancer in laboratory animals). This research evaluated the THMs concentrations in the following sampling sites: CWTP, Río Hondo and Pinas Abajo schools, Comerio Health Center (CDT), and the Vázquez Ortiz family, in the municipality of Comerio Puerto Rcio. The results show that the factors affecting the formation of THMs occur in different concentrations across the distribution line. There are not specific ranges to determine the formation of THMs in drinking water when the chemical and physical parameters were evaluated. Three different nanostructured materials (graphene, mordenite (MOR) and multiwalled carbon nanotubes (MWCNTs)) were used in this research, to reduce the THMs formation by adsorption in specific contact times. The results showed that graphene is the best nanomaterial to reduce THMs in drinking water. Graphene can reduce 80 parts per billion (ppb) of THMs in about 2 hours. In addition mordenite can reduce approximately 80 ppb of THMs and MWCNTs adsorbs 71 ppb of THMs in the same period of time respectively. In order to complement the adsorption results previously obtained, total organic carbon (TOC) analyses were measured, after different contact times with the nanomaterials. During the first 30 minutes, graphene C/Co was reduced to c.a. 0.9, in presence of each THMs solution. MWCNTs and MOR show similar adsorptions trends in comparison with graphene.
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