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Identification and Quantification of Monosaccharides in Aloe vera Gel by Acid and Enzymatic Hydrolysis and Wet Heat Treatment

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Food and Nutrition Sciences 2017年第8期8卷 840-853页

作者： Dianeli Madera Pina Carlos Hernán Herrera Méndez Lourdes Vargas y Vargas Herbert Loria Sunza jorge tamayo cortez Research and Postgraduate Division Instituto Tecnológico de MéridaMéridaMexico Agroindustrial Engineering Department Campus Celaya-SalvatierraUniversidad de GuanajuatoSalvatierraMéxico

Aloe vera (Aloe barbadensis Miller) possesses curative and therapeutic properties attributed to the polysaccharides found in its tissue. This work aimed to study hydrolyzed (chemical and enzymatical) Aloe vera gel extracts using ultrafiltration membranes with a pore size of 0.22 micron (μm). Nine chemical treatments were achieved with H2SO4 and three wet heat treatments were carried out at a pressure of 1.2 lbf/in2 for 15 minutes;in both cases, three different concentrations of Aloe vera gel juice (AGJ) were used: 1.5%, 2.5% and 3.5% w/w. The concentrations of H2SO4 were 0.10%, 0.25% and 0.40% w/w. Chemical experiments are performed over a factorial 32 design and results were analyzed using SPSS software (version 17, SPSS Inc.), finding the one labeled T7 (15 ml of AGJ 3.5% with 15 ml of H2SO4 0.10% added) the best of them, as it leaded to 0.0446 mg/ml of liberated glucose. Among the three wet heat treatments, the one labeled TC3 (15 ml of AGJ 3.5% with 15 ml of H2O added) was the best-performing one, as it leaded to 0.292 mg/ml of liberated glucose. Furthermore, an enzymatic hydrolysis was carried out using Novozymes’ Pectinex? AR and Viscozyme?. Hydrolisis with both enzymes yield to better results than acid hydrolysis: in the treatment with Pectinex? AR, 3.282 mg/ml of liberated glucose were obtained and 3.302 mg/ml in the treatment with Viscozyme?. The hydrolyzed substances obtained by acid and enzymatic hydrolysis, as well as by wet heat treatment, were subsequently analyzed by thin layer chromatography (TLC), using glucose, galactose and arabinose 1000 ppm solutions as reference patterns. Among the treatments by H2SO4, the one labeled T4 obtained an Rf value of 50, the same as on the galactose reference pattern.

关键词： Carbohydrates Enzyme Mucilage Reducing Sugars Retention Factor

Purification and Partial Characterization of Polyphenol Oxidase from Sapodilla Plum (<i>Achras sapota</i>)

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Food and Nutrition Sciences 2013年第7期4卷 727-734页

作者： jorge tamayo cortez Carlos Hernán Herrera Méndez Enrique Sauri Duch María de Lourdes Vargas y Vargas Sara Solís Pereira Agroindustrial Engineering Department Campus Celaya-Salvatierra Universidad de Guanajuato Salvatierra Mexico. Research and Postgraduate Division Instituto Tecnológico de Mérida Merida Mexico

The browning of fruits can be considered as an enzymatic oxidation which is believed to be one of the main causes of quality loss during post-harvest handling. The enzymes responsible for this are the oxidoreductases;the polyphenol oxidase (PPO) (monophenol, o-diphenol, oxygen oxidoreductase;EC 1.***.18.1) belongs to this group. This enzyme, which is found in the sapodilla plum (Achras sapota), was purified using a phenylsepharose and a SephacrylS-200 columns. The molecular weight of the purified enzyme was estimated to be about 66 kDa by gel filtration and 29 kDa by SDS-PAGE. A single protein band was found using the latter system (SDS-PAGE), which shows that the PPO of the pulp of the sapodilla plum may be composed of two protein subunits with similar molecular weight. The optimum pH was 7.0 and the optimum temperature 60℃. The most effective inhibitors tested were ascorbic acid, sodium metabisulfite and acetic acid.

关键词： Enzymatic System Oxidation Polyphenol Oxidase Browning Process Nutritional Value

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认知无线电网络中基于博弈论的合作频谱感知

认知无线电网络中基于博弈论的合作频谱感知

作者： jorge abraham Rios Suarez 哈尔滨工业大学

学位级别：硕士

当前,新无线设备的增长增加了资源的稀缺性,而认知无线电网络为频谱需求的扩大提供开创性的答案。本文的主要思想是频谱传感的概念,它包含对主要用户存在检测,因为影响系统如阴影、空间多样性和多路径等现象,下一个关键概念是合作,即所... 详细信息

当前,新无线设备的增长增加了资源的稀缺性,而认知无线电网络为频谱需求的扩大提供开创性的答案。本文的主要思想是频谱传感的概念,它包含对主要用户存在检测,因为影响系统如阴影、空间多样性和多路径等现象,下一个关键概念是合作,即所有用户相互交互,以便检测以前所有现象的效果,最后是博弈理论的概念,它呈现社会,经济或任何类型的问题外推成博弈,在这种情况下,基于合作决策是比较合适的。研究的重点是用户对具有多个SU和多个主要用户的认知无线电网络中的协同频谱传感和接入策略。该方法提出每个用户根据自己的业务需求,与其他用户共同决定接入和感知的信道,另外还可以决定接入哪个信道。当用户没有数据要传输时,可以节省能量以备将来传输。首先,本研究探讨了基于流量需求的合作策略,即每个用户在确定的时间跨度中感知一个通道。该联盟具有不可转让的实用程序,其中所有用户都会获得与联盟对应的值,该值将用于计算吞吐量和能源效率。在这种情况下,联盟组建是一个高度复杂的问题,很难使用,为了克服这种复杂性,提出了一种新的联盟组建算法。结果表明,该算法具有高能效的高通量。然后,通过在整个传感时间中感应多个通道,提高了策略复杂性,从而扩展了合作范围。博弈设置为不可转让的实用程序重叠博弈。为了实现纳什稳定结构,对分析算法进行了修改。实践证明,该算法在有限重复次数后能够稳定,提高了频谱效率。该算法要求用户之间最佳的信息交换和迭代编号。与不相交算法和重叠形成算法相比,实现高吞吐量。本文分析自适应传输功率控制方案,以在保证较高吞吐量的同时降低传输能耗。性能评估考虑了影响算法性能的几个不同因素,如用户数、流量需求和能量效率下界。最后给出了重叠联盟结构的快照和实现不同算法时的迭代次数。仿真结果表明,该算法在受用户收益影响的系统吞吐量方面优于其他算法。

关键词：频谱感知博弈论重叠联盟形成效率

Main Polysaccharides Isolated and Quantified of Aloe vera Gel in Different Seasons of the Year

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Food and Nutrition Sciences 2016年第6期7卷 447-453页

作者： Berenice Aranda Cuevas Carlos Hernán Herrera Méndez Ignacio Islas Flores Sara Solís-Pereira Luis Cuevas-Glory Gerardo Rivera Muñoz María de Lourdes Vargas y Vargas jorge tamayo cortez Research and Postgraduate Division Instituto Tecnológico de Mérida Mérida Mexico Agroindustrial Engineering Department Universidad de Guanajuato Campus Celaya-Salvatierra Salvatierra México Centro de Investigación Científica de Yucatán Mérida México

We developed and implemented a methodology that allowed extracting and evaluating high molecular weight polysaccharides present in the gel of Aloe barbadensis Miller. One of the fractions evaluated revealed the presence of high molecular weight carbohydrates (200 kDa) with a behavior similar to that of acemannan and another fraction with compounds of molecular weights between 17 and 47 kDa. We quantified the concentration of acemannan for two different growing periods. The concentration of acemannan in the high molecular weight fraction was 99.97 ppm in the rainy season and 106.03 ppm in the dry season. The concentration of acemannan in the fraction of low molecular weight was 9.364 ppm during the season of greatest rainfall and 26.939 ppm in the dry season.

关键词： Acemannan Aloe vera Gel Polysaccharides Rainy Season Dry Season

Serum levels of undercarboxylated osteocalcin are related to cardiovascular risk factors in patients with type 2 diabetes mellitus and healthy subjects

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World Journal of Diabetes 2017年第1期8卷 11-17页

作者： Sergio Sanchez-Enriquez Isabel Thalia Ballesteros-Gonzalez JoséRafael Villafán-Bernal Sara Pascoe-Gonzalez Edgar Alfonso Rivera-Leon Blanca Estela Bastidas-Ramirez jorge David Rivas-Carrillo Juan Luis Alcala-Zermeno Juan Armendariz-Borunda Iris Monserrat Llamas-Covarrubias abraham Zepeda-Moreno Biochemistry Laboratory Molecular Biology and Genomics Department University Center of Health Sciences University of Guadalajara Academic Group UDG-CA-533 Multidisciplinary Study of Chronic and Degenerative Diseases Molecular Biology and Genomics Department University Center of Health Sciences University of Guadalajara Departamento de Jóvenes Investigadores y Cátedras del Consejo Nacional de Ciencia y Tecnología (CONACYT) Departamento de Cirugía Centro Universitario de Ciencias de la Salud Universidad Autónoma de Aguascalientes Physiology Department University Center of Health Sciences University of Guadalajara Institute of Degenerative Chronic Diseases Molecular Biology and Genomics Department University Center of Health Sciences University of Guadalajara Molecular Biology and Genomics Department University Center of Health SciencesUniversity of Guadalajara Institute of Cancer Research in Child and Adolescent University Center of Health Sciences University of Guadalajara

AIM To determine a potential relationship between serum undercarboxylated(uc OC) concentration and cardiovascular risk factors in type 2 diabetes(T2D) patients and healthy subjects(HS).METHODS A cross-sectional study was conducted on 140 subjects classified into two groups, 70 with T2D and 70 HS. Medical history and physical examination with anthropometric measurements were obtained from all subjects. Body fat percentage was determined by bioelectrical impendency analysis. Serum uc OC concentration was determined by enzyme immunoassay,while serum levels of insulin and hsC RP were obtained using high sensitivity enzyme-linked immunosorbent assay. Insulin resistance was determined using the homeostasis model assessment-IR. Lipid profile [triglycerides,total cholesterol(TC), high-density lipoproteins(HDL-c),low density lipoproteins(LDL-c), very low-density lipoproteins] was determined by spectrophotometry and standard formulas when applicable. RESULTS The T2D patient group showed significantly higher values of waist circumference, waist-to-hip ratio, systolic blood pressure(SBP), diastolic blood pressure(DBP),current smoking, and alcohol use when compared to the HS group(P < 0.05). We observed a significantly lower serum ucO C concentration in T2D than in HS(1.5 ± 1.4vs 2.3 ± 1.8, P < 0.05). In the whole study population,ucO C concentration was inversely correlated with body mass index(BMI)(r =-0.236, P < 0.05), fasting plasma glucose(r =-0.283, P < 0.01) and HDL-c(r =-0.255,P < 0.05); and positively correlated with LDL-c/HDL-c ratio(r = 0.306, P < 0.05) and TC/HDL-c ratio(r =0.284, P < 0.05). In the T2D group, serum uc OC concentration was inversely correlated with BMI(r =-0.310, P < 0.05) and body-fat percentage(r =-0.311,P < 0.05), and positively correlated with DBP(r = 0.450,P < 0.01). In HS group a positive correlation between serum levels of uc OC and SBP(r = 0.277, P < 0.05)was observed. CONCLUSION Serum uc OC is a potential marker for cardiovascular risk in Mex

关键词： Bone Osteocalcin Glucose metabolism Diabetes Cardiovascular risk

Volcaniclastic Deposit Analysis Using Grain Size, Digital and Stereological Techniques

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Open Journal of Civil Engineering 2023年第4期13卷 723-741页

作者： Alberto Rangel-Durán Vanessa Verónica Espejel-García Alejandro Villalobos-Aragón Daphne Espejel-García jorge Lucero-Álvarez abraham Gilberto Mendez-Salas Facultad de Ingeniería Universidad Autónoma de Chihuahua Chihuahua México Facultad de Zootecnia y Ecología Universidad Autónoma de Chihuahua Chihuahua México

This study undertook a comprehensive sedimentological and grain-size analysis of two previously uncharacterized volcanoclastic deposits exposed in the northwestern sector of Chihuahua City, Mexico. The primary objective was to propose a systematic genetic classification for these deposits, employing traditional sedimentological techniques and an advanced computerized granulometric analysis technique based on orthogonal images to discern their grain size distribution. Through these studies, evidence was sought to classify them genetically, presenting arguments to define them either as a lahar or a volcanic debris avalanche. Results were critically compared against existing literature data pertaining to lahars and debris avalanches, yielding moderate success. The analysis identified one of the deposits as a non-eruptive or post-eruptive lahar. This identification was substantiated by the delineation of distinct overbank and transition facies within the deposit, providing compelling evidence for its genetic classification.

关键词： Volcaniclastic Lahar Avalanche Statistics Chihuahua

The Role of Ultrasound and Air Leak Measurement in Assessing Lung Expansion after Thoracic Surgery

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Surgical Science 2015年第8期6卷 352-357页

作者： abraham Chavarín Laureano Molins Jose M. Mier Juan J. Fibla Cristina Izquierdo-Vidal Cristina Simon Angela Guirao jorge Hernandez Department of Thoracic Surgery Hospital Universitari Sagrat Cor Barcelona Spain Department of Thoracic Surgery Hospital Clinic Barcelona Spain Department of Thoracic Surgery Instituto Nacional de Enfermedades Respiratorias México D.F. México Department of Radiology Hospital Universitari Sagrat Cor Barcelona Spain

Objective: To determine if lung ultrasound semiology is applicable to the post-surgical hemithorax, and its value in the evaluation of lung expansion in the postoperative period when paired with the use of digital chest drain systems. Methods: Prospective observational study including all patients undergoing thoracic surgery from June 2012 to March 2013. Patients undergoing pleurodesis or hemodynamically unstable were not considered candidates. Final inclusion in the study was based on the availability of digital chest drain system. A transthoracic lung ultrasound evaluation of the anterior and anterolateral windows was performed 20 minutes after chest drain placement. Presence or not of lung sliding and air leak values taken from the digital chest drain system were recorded. Data were submitted to a binomial classification test for analysis. Results: Forty-nine patients were included, yielding a total of 64 hemithoraces. Lung sliding was seen in 53 cases (82.8%), and an air leak value of 20 ml/min or less in 56 cases (87.5%). Sensitivity was 92.8% (95% CI: 82.6% to 97.9%) and specificity 87.5% (95% CI: 47.3% to 97.9%). Positive predictive value was 98.1%, and negative predictive value was 63.6%. Conclusions: Transthoracic lung ultrasound is a useful technique that can complement the use of digital chest drain systems in the evaluation of post-surgical lung expansion. The incorporation of lung ultrasound can greatly reduce the need for chest radiographs in thoracic surgery departments.

关键词： Thoracic Surgery Pneumothorax Ultrasonography Lung Expansion Chest Radiograph

SARS-CoV-2:Air pollution highly correlated to the increase in *** case of Guadalajara,Jalisco,Mexico

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Infectious Disease Modelling 2023年第2期8卷 445-457页

作者： Elizabeth Torres-Anguiano Itzel Sanchez-Lopez Angeles Garduno-Robles jorge David Rivas-Carrillo Edgar Alfonso Rivera-Leon Sergio Sanchez-Enríquez Luis Fernando Ornelas-Hernandez Fernando Zazueta Leon-Quintero Eduardo Narciso Salazar Leon-Quintero Guillermo Enrique Juarez-Lopez Fernando Antonio Sanchez-Zubieta Mariana Ochoa-Bru abraham Zepeda-Moreno Onkogenetik/Mexicana de Investigacion y Biotectogía S.A.de C.V GuadalajaraJaliscoMexico Unidad de Biología Molecular Investigacion y DiagnosticoHospital San JavierGuadalajaraJaliscoMexico Departamento de Fisiología Centro Universitario de Ciencias de la SaludUniversidad de GuadalajaraGuadalajaraJaliscoMexico Departamento de Biología Molecular y Genomica Centro Universitario de Ciencias de la SaludUniversidad de GuadalajaraGuadalajaraJaliscoMexico Departamento de Clínicas Centro Universitario de los AltosUniversidad de GuadalajaraTepatitlan de MorelosJaliscoMexico Departamento de Clínicas Medicas Centro Universitario de Ciencias de la SaludUniversidad de GuadalajaraGuadalajaraJaliscoMexico Servicio de Hemato-Oncología Pediatrica Hospital Civil de Guadalajara“Dr.Juan I.Menchaca”GuadalajaraJaliscoMexico Hospital Civil de Guadalajara“Fray Antonio Alcalde” GuadalajaraJaliscoMexico

Objectives:To determine whether air pollution or changes in SARS-CoV-2 lineages lead to an increase in ***:Descriptive statistics were used to calculate rates of infection(2020-2021).RT ePCR was used to compare viral loads from October 2020 to February *** sequencing(NGS)(n=92)was used to examine and phylogenetically map SARS-CoV-2 lineages.A correlative“air pollution/temperature”index(I)was developed using regression ***_(2.5),PM_(10),O_(3),NO_(2),SO_(2),and CO concentrations were analyzed and compared to the ***:The mortality rate during the last year was~32%.Relative SARS-CoV-2 viral loads increased in December 2020 and January *** revealed that approximately 80%of SARS-CoV-2 linages were B.1.243(33.7%),B1.1.222(11.2%),B.1.1(9%),B.1(7%),B.1.1.159(7%),and B.1.2(7%).Two periods were analyzed,the prehigh-and high-mortality periods and no significant lineage differences or new lineages were *** correlations of air pollution/temperature index values with mortality were found for IPM_(2.5) and IPM_(10).INO_(2).ISO_(2),and ICO but not for O_(3).Using ICO,we developed a model to predict mortality with an estimated variation of~±5 deaths per day.

关键词： Air pollution COVID-19 Guadalajara Mexico SARS-CoV-2 SARS-CoV-2 lineages

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 ***：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 ***：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