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Biomedical and Environmental Sciences 2016年第3期29卷 187-196页

作者： Javier Edo.Vargas Jenny Dussan Biological Sciences Universidad De Los AndesBogota 111711Colombia

Objective Assessment of the bacterium L. sphaericus as a dual-action candidate for biological control of mosquito-borne diseases and bioremediation of toxic metals. Methods Larvae of the mosquito, C quinquefasciatus, were first evaluated for metal tolerance and then exposed to 5 ppm cadmium, chromium, arsenic, and lead in assays together with seven strains of L. sphaericus. A probit regression analysis was used to estimate the LCso of Cd, Cr, As, and Pb to C. quinquefosciatus. An analysis of covariance and multifactorial ANOVA examined the metal biosorption and larvicidal properties of the seven strains of L. sphaericus. Results We found that L. sphaericus adsorbed the toxic metal ions and was toxic against mosquito larvae. The L. sphoericus strain 111（3）7 resulted in a larvae mortality of over 80% for all the tested metals. This strain also exhibited the capacity to adsorb 76% of arsenic, 32% of lead, 25% of chromium, and 7% of cadmium. Conclusion This study found combined metal adsorption and larval toxicity associated with three strains of L. sphaericus [111（3）7, OT4b.31, and CBAM5]. This suggests that a combination of these strains shows strong dual potential for biological control of mosquitos in heavy metal-contaminated areas and remediate the heavy metal contamination as well.

关键词： Lysinibacillus sphaericus Culex quinquefasciatus Entomopathogen Toxic metals Heath

Depth to the bottom of magnetic layer in South America and its relationship to Curie isotherm,Moho depth and seismicity behavior

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Geodesy and Geodynamics 2018年第1期9卷 93-107页

作者： javier Idárraga-García Carlos A.vargas Research Group on Geophysics Universidad Nacional de ColombiaBogotáColombia Deportment of Geosciences.Universidad Nacional de Colombia.Bogota.Colombia

We have estimated the DBML（depth to the bottom of the magnetic layer） in South America from the inversion of magnetic anomaly data extracted from the EMAG2 grid. The results show that the DBML values, interpreted as the Curie isotherm, vary between -10 and -60 km. The deepest values（〉-45） are mainly observed forming two anomalous zones in the central part of the Andes Cordillera. To the east of the Andes, in most of the stable cratonic area of South America, intermediate values（between -25 and-45 km） are predominant. The shallowest values（〈-25 km） are present in northwestern corner of South America, southern Patagonia, and in a few sectors to the east of the Andes Cordillera. Based on these results, we estimated the heat flow variations along the study area and found a very good correlation with the DBML. Also striking is the observation that the thermal anomalies of low heat flow are closely related to segments of flat subduction, where the presence of a cold and thick subducting oceanic slab beneath the continent, with a virtual absence of hot mantle wedge, leads to a decrease in the heat transfer from the deeper parts of the system.After comparing our results with the Moho depths reported by other authors, we have found that the Curie isotherm is deeper than Moho in most of the South American Platform（northward to -20°S）, which is located in the stable cratonic area at the east of the Andes. This is evidence that the lithospheric mantle here is magnetic and contributes to the long wavelength magnetic signal. Also, our results support the hypothesis that the Curie isotherm may be acting as a boundary above which most of the crustal seismicity is concentrated. Below this boundary the occurrence of seismic events decreases dramatically.

关键词： Magnetic layer depth Curie isotherm Heat flow Crustal seismicity Flat subduction South America

Assessing above-ground biomass-functional diversity relationships in temperate forests in northern Mexico

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Forest Ecosystems 2021年第1期8卷 95-108页

作者： Benedicto vargas-Larreta Jorge Omar López-Martínez Edgar J.González Joséjavier Corral-Rivas Francisco javier Hernández Tecnológico Nacional de México/Instituto Tecnológico de El Salto 34942 El SaltoDurangoMexico Cátedras CONACYT1582Av.Insurgentes SurCiudad de MéxicoMexico El Colegio de la Frontera Sur 77014ChetumalQuintana RooMexico Departamento de Ecología y Recursos Naturales Facultad de CienciasUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoMexico Facultad de Ciencias Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.Durango s/nCol.Valle del Sur34120 DurangoMexico

Background:Studies on the relationship between biodiversity and ecosystem productivity have suggested that species richness and functional diversity are the main drivers of ecosystem processes.Several patterns on this relationship have been found,including positive,unimodal,negative,and neutral trends,keeping the issue controversial.In this study,taxonomic diversity and functional diversity as drivers of above-ground biomass(AGB)were compared,and the mechanisms that influence biomass production were investigated by testing the complementarity and the mass-ratio hypotheses.Methods:Using data from 414 permanent sample plots,covering 23%of temperate forest in the Sierra Madre Oriental(México),we estimated the above-gound biomass(AGB),taxonomic and functional diversity indices,as well as community weighted mean values(CWM)for three functional traits(maximum height,leaf size and wood density)for trees≥7.5 cm DBH,in managed and unmanaged stands.To compare taxonomic diversity differences between managed and unmanaged stands we carried out a rarefaction analysis.Furthermore,we evaluated the relationship between AGB and taxonomic and functional diversity metrics,as well as CWM traits throught spatial autoregressive models.Results:We found a hump-shaped relationship between AGB and species richness in managed and unmanaged forests.CMW of maximum height was the most important predictor of AGB in both stands,which suggested that the mechanism underlaying the AGB-diversity relationship is the dominance of some highly productive species,supporting the mass-ratio hypothesis.Above-ground biomass was significantly correlated with three of the five functional diversity metrics,CWM maximum height and species richness.Our results show the importance of taking into account spatial autocorrelation in the construction of predictive models to avoid spurious patterns in the AGBdiversity relationship.Conclusion:Species richness,maximum height,functional richness,functional dispersion and RaoQ indices relate with above-ground biomass produ

关键词： Taxonomic diversity Functional diversity Complementarity hypothesis Mass-ratio hypothesis

Effect of dietary supplementation with olive and sunflower oils on lipid profile and liver histology in rats fed high cholesterol diet

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Asian Pacific Journal of Tropical Medicine 2017年第6期10卷 609-613页

作者： Sandra Mara Pimentel Duavy Gerson javier Torres Salazar Gerlania de Oliveira Leite Assis Ecker Nilda vargas Barbosa Departamento de Química Universidade Regional do Cariri(URCA)Campus Pimenta Departamento de Bioquímica e Biologia Molecular Programa de Pós-Graduacao em Ciências Biológicas:Bioquímica ToxicológicaUniversidade Federal de Santa Maria(UFSM)Campus Universitário-Camobi Departamento de Farmacologia Programa de Pós-Graduacao em FarmacologiaUniversidade Federal de Santa Maria(UFSM)Campus Universitário-Camobi

Objective: To compare the effects of high-monounsaturated(MUFA) and polyunsaturated fatty acids(PUFA) against the metabolic disorders elicited by a high-cholesterol diet(HC) in rats. Methods: Using in vivo dietary manipulation, rats were fed with different diets containing 4% soybean oil(cholesterol free diet) and 1% HC containing 12% olive oil(HC+OO) enriched with MUFA and 12% sunflower oil(HC+SO) enriched with PUFA for 60 d. Serum lipid levels and hepatic steatosis were evaluated after the treatment period. Results: Comparatively, rats treated with HC+OO diet experienced a decrease in the serum LDL-C, VLDL-C and CT levels compared to those fed with HC+SO diet(P<0.05). Otherwise, HC+OO provoked significant microvesicular steatosis situated in the hepatic acinar zone 1. Conclusions: HC+OO diet has high absorption velocity in the acinar zone 1 of liver compared to the HC+SO diet. Based on this, the reduction of the LDL-C, VLDL-C and CT serum levels in the animals treated with HC+OO diet can be caused by the delay in the FA release to the blood.

关键词： Cholesterol diets Olive oil Sunflower oil Serum lipids Liver steatosis

Tick-Borne Rickettsial Pathogens in Rodents from Mexico

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Journal of Biomedical Science and Engineering 2014年第11期7卷 884-889页

作者： Carolina G. Sosa-Gutiérrez Margarita vargas javier Torres Guadalupe Gordillo-Pérez Facultad de Agrobiología Universidad Michoacana de San Nicolas de Hidalgo Uruapan México Unidad de Investigación Médica de Enfermedades Infecciosas y Parasitarias Hospital de Pediatría Centro Médico Nacional Siglo XXI Instituto Mexicano del Seguro Social Mexico City Mexico

Tick-Borne Rickettsial Diseases (TBRD) are emerging zoonotic diseases, and a problem of human health and veterinary medication. The distribution of these diseases is related to the distribution of vector. The presence of pathogens in the host is a risk indicator of population exposure to these areas. A total of 478 tissues samples from rodents, A. phagocytophilum 18 (3.7%), E. canis 47 (9.8%), Rickettsia rickettsii 18 (3.7%) and E. chaffeensis 19 (3.9%) were detected using species-specific PCR assay. It is the first report in Mexico the presence of rodents infected with A. phagocytophilum and E. chaffeensis. The rodent Peromyscus spp. were the most commonly prevalent host of infection for all the bacteria’s. We have to consider as host of TBRD transmitter and provide a useful contribution to understanding their epidemiology. The health sector should be considered all the fevers of unknown causes in humans and animals in Mexico as infections by these vector-borne rickettsial pathogens.

关键词： Anaplasma phagocytophilum Ehrlichia chaffeensis Rickettsia rickettsii Ehrlichia canis Rodents

Driving Factors for Forest Fire Occurrence in Durango State of Mexico:A Geospatial Perspective

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Chinese Geographical Science 2010年第6期20卷 491-497页

作者： Diana Avila-Flores Marin Pompa-Garcia Xanat Antonio-Nemiga Dante A Rodriguez-Trejo Eduardo vargas-Perez javier Santillan-Perez Forestry Division University of Chapingo Faculty of Forestry Juarez University of the State of DurangoRio Papaloapan and Durango Blvd Faculty of Geography Autonomous University of Mexico StateCerro de Coatepec s/nCiudad Universitaria

Forest fire is one of the major causes of forest loss and therefore one of the main constraints for sustainable forest management worldwide.Identifying the driving factors and understanding the contribution of each factor are essential for the management of forest fire occurrence.The objective of this study is to identify variables that are spatially related to the occurrence and incidence of the forest fire in the State of Durango,Mexico.For this purpose,data from forest fire records for a five-year period were analyzed.The spatial correlations between forest fire occurrence and intensity of land use,susceptibility of vegetation,temperature,precipitation and slope were tested by Geographically Weighted Regression(GWR) method,under an Ordinary Least Square estimator.Results show that the spatial pattern of the forest fire in the study area is closely correlated with the intensity of land use,and land use change is one of the main explanatory variables.In addition,vegetation type and precipitation are also the main driving factors.The fitting model indicates obvious link between the variables.Forest fire was found to be the consequence of a particular combination of the environmental factors,and when these factors coexist with human activities,there is high probability of forest fire occurrence.Mandatory regulation of human activities is a key strategy for forest fire prevention.

关键词：森林火灾地理空间墨西哥土地利用变化人类活动因素驾驶最小二乘估计森林管理

利用腐植酸改良矿山土壤并促进香根草对Cu和Zn吸收的植物修复

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腐植酸 2018年第1期 47-47页

作者： Carmen vargas javier Pérez-Esteban Consuelo Escolástico 李双(译) 不详中国腐植酸工业协会

利用植物修复矿山污染土壤，需要选择快速生长的、根深蒂固的、高生物量和金属耐性的植物，并利用土壤改良剂促进植物对金属的吸收。本研究采用盆栽试验，评估腐植酸和香根草（Chrysopogon zizanioides）对矿山土壤中Cu和zn植物修复的... 详细信息

利用植物修复矿山污染土壤，需要选择快速生长的、根深蒂固的、高生物量和金属耐性的植物，并利用土壤改良剂促进植物对金属的吸收。本研究采用盆栽试验，评估腐植酸和香根草（Chrysopogon zizanioides）对矿山土壤中Cu和zn植物修复的综合利用。

关键词：植物修复土壤改良剂综合利用污染土壤 n吸收香根草腐植酸矿山

Refractive errors among children, adolescents and adults attending eye clinics in Mexico

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International Journal of Ophthalmology(English edition) 2017年第5期10卷 796-802页

作者： Francisco Gomez-Salazar Abraham Campos-Romero Humberto Gomez-Campana Cinthia Cruz-Zamudio Mariano Chaidez-Felix Nidia Leon-Sicairos Jorge Velazquez-Roman Hector Flores-Villasenor Secundino Muro-Amador Alma Marlene Guadron-Llanos javier J.Martinez-Garcia Joel Murillo-Llanes Jaime Sanchez-Cuen Alejando Llausas-vargas Gerardo Alapizco-Castro Ana Irineo-Cabrales Enrique Graue-Hernandez Tito Ramirez-Luquin Adrian Canizalez-Roman Salud Digna Para Todos I.A.P Culiacan Sinaloa 80000Mexico CIASaP School of Medicine Autonomous University of Sinaloa Culiacan Sinaloa 80246 Mexico Pediatric Hospital of Sinaloa Culiacan Sinaloa 80200Mexico The Women's Hospital Secretariat of Health Culiacan Sinaloa 80127 Mexico Department of Gastroenterology Regional Hospital ISSSTECuliacan 80230 Sinaloa Mexico Education and Research Department Regional general Hospital No. 1 IMSS Culiacan Sinaloa 80220 Mexico Department of Cornea and Refractive Surgery Institute of Ophthalmology 'Conde de Valenciana' Mexico City 06800Mexico

AIM：To assess the proportion of refractive errors in the Mexican population that visited primary care optometry clinics in fourteen states of Mexico. METHODS：Refractive data from 676 856 patients aged 6 to 90 y were collected from optometry clinics in fourteen states of Mexico between 2014 and 2015. The refractive errors were classified by the spherical equivalent（SE）, as follows：sphere＋？ cylinder. Myopia（SE〉-0.50 D）, hyperopia（SE〉＋0.50 D）, emmetropia（-0.50≤SE≤＋0.50）, and astigmatism alone（cylinder≥-0.25 D）. A negative cylinder was selected as a notation.RESULTS：The proportion（95% confidence interval） among all of the subjects was hyperopia 21.0%（20.9-21.0）, emmetropia 40.7%（40.5-40.8）, myopia 24.8%（24.7-24.9） and astigmatism alone 13.5%（13.4-13.5）. Myopia was the most common refractive error and frequency seemed to increase among the young population（10 to 29 years old）, however, hyperopia increased among the aging population（40 to 79 years old）, and astigmatism alone showed a decreasing trend with age（6 to 90y; from 19.7% to 10.8%）. There was a relationship between age and all refractive errors（approximately 60%, aged 50 and older）. The proportion of any clinically important refractive error was higher in males（61.2%） than in females（58.3%; P〈0.0001）. From fourteen states that collected information, the proportion of refractive error showed variability in different geographical areas of Mexico.CONCLUSION：Myopia is the most common refractive error in the population studied. This study provides the first data on refractive error in Mexico. Further programs and studies must be developed to address the refractive errors needs of the Mexican population.

关键词： refractive errors hyperopia myopia astigmatism

Antimalarial Activity of an Alkaloid Mixture Isolated from the Tender Leaves of the Nectandra membranacea （Laureaceae）

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Journal of Life Sciences 2018年第3期12卷 134-140页

作者： Vanessa Bagnarello-Madrigal Daniela Rodríguez-Chaves javier Alpizar-Cordero Alonso Calvo-vargas Maribel Cordero-Villalobos Misael Chinchilla-Carmona Idalia Valerio-Campos Ronald Sánchez -Porras Departamento de Química Universidad de Ciencias Médicas (UCIMED) San José 10108 Costa Rica Departamento de Investigación Básica Universidad de Ciencias Médicas (UCIMED) San José 10108 Costa Rica Sección de Biología Sede Occidente Universidad de Costa Rica San José 10108 Costa Rica

Antiprotozoal Activity of a <i>Thymus vulgaris</i>Methanol Extract and Its Fractions

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Health 2017年第7期9卷 1081-1094页

作者： Jesús Norberto Garza-González javier vargas-Villarreal Ma Julia Verde-Star Catalina Rivas-Morales Azucena Oranday-Cárdenas Magda E. Hernandez-García Laura De La Garza-Salinas Francisco González-Salazar Department of Chemistry Phytochemistry and Analytical Chemistry Lab Faculty of Biological Sciences University Autonomous of Nuevo Leon San Nicolas de los Garza Mexico Department of Basic Sciences Division of Health Sciences University of Monterrey San Pedro Garza Garcia Mexico Laboratory of Biochemistry and Cell Physiology Division of Cellular and Molecular Biology Center for Biomedical Research of the Northeast Mexican Social Security Institute Monterrey Mexico Mexican Social Security Institute Nuevo Leon Delegation Monterrey Mexico

Introduction: Thymus vulgaris is used in traditional medicine to treat gastrointestinal diseases because of its antifungal, antibacterial, and antispasmodic activity. Objective: To verify whether Thymus vulgaris also has antiprotozoal activity against Trichomonas vaginalis, Giardia lamblia and Entamoeba histolytica trophozoites. Materials and methods: Conventional cultures of parasites were measured on the third day during the logarithmic growth phase. The antiprotozoal activity of the methanol extract and its fractions were evaluated comparing growth in cultures with and without extracts. Next, the extract was fractionated by polarity-based partitioning. Then, the purity of each fraction was determined by thin layer chromatography (TLC). The percentage of growth inhibition was calculated with respect to untreated controls. The 50% inhibitory concentration (IC50) of each extract was calculated by PROBIT analysis. Results: We found that a methanol extract of the aerial parts of Thymus vulgaris, at 300 μg/mL, inhibited the in vitro growth of G. lamblia and T. vaginalis, while E. histolytica growth was poorly inhibited. The methanol extract was further separated into mixtures of ursolic, oleanolic, and betulinic acids. The IC50 values of ursolic acid against G. lamblia and T. vaginalis were 8.12 μg/mL and 5.51 μg/mL, respectively. Conclusions: The methanol extract fraction containing ursolic acid obtained from Thymus vulgaris has antiprotozoal activity against G. lamblia and T. vaginalis trophozoites.

关键词： Thymus vulgaris Trichomonas vaginalis Giardia lamblia Entamoeba histolytica Antiprotozoal Agents