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Advances in Nanoparticles 2014年第3期3卷 114-121页

作者： Juan Adrián Ramos Guivar arturo isaías martínez Ana Osorio Anaya Luis De Los Santos Valladares Lizbet León Félix Angel Bustamante Dominguez Cavendish Laboratory Department of Physics University of Cambridge Cambridge UK Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional Cinvestav Unidad Saltillo Ciudad de México México Ciudad de México México Laboratorio de Cerámicos y Nanomateriales Facultad de Ciencias Físicas Universidad Nacional Mayor de San Marcos Lima Perú Laboratorio de Nanotecnología e Innovación Tecnológica Departamento de Química e Ingeniería Química Universidad Nacional Mayor de San Marcos Lima Perú Núcleo de Física Aplicada Instituto de Física Universidade de Brasília Brasília Brasil

Structural and magnetic studies of monophasic maghemite (γ-Fe2O3) magnetic nanocrystallites (MNCs) synthesized by the co-precipitation chemical route are reported in this paper. For the synthesis, a starting precursor of magnetite (Fe3O4) in basic medium was oxidized at room temperature by adjusting the pH = 3.5 at 80°C in an acidic medium without surfactants. X-ray diffraction (XRD) pattern shows widened peaks indicating nanometric size and Rietveld Refinement confirms only one single-phase assigned to γ-Fe2O3 MNCs. High Resolution Transmission Electron Microscopy (HR-TEM) demonstrates the formation of nanoparticles with diameter around D ≈ 6.8 ± 0.1 nm which is in good agreement with Rietveld Refinement (6.4 ± 1 nm). A selected area electron diffraction pattern was carried out to complement the study of the crystalline structure of the γ-Fe2O3 MNCs. M(H) measurements taken at different temperatures show almost zero coercivity and remanence indicating superparamagnetic domain and high magnetic saturation.

关键词： Monophasic Nanomaghemite Rietveld Refinement TEM SAED M-H Loops ZFC

Oxidative stress,the blood-brain barrier and neurodegenerative diseases:The critical beneficial role of dietary antioxidants

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Acta Pharmaceutica Sinica B 2023年第10期13卷 3988-4024页

作者： Jin Feng Youle Zheng Mingyue Guo Irma Ares marta martínez Bernardo Lopez-Torres María-Rosa martínez-Larran aga Xu Wang arturo Anadon María-Aranzazu martínez National Reference Laboratory of Veterinary Drug Residues(HZAU)and MAO Key Laboratory for Detection of Veterinary Drug Residues Huazhong Agricultural UniversityWuhan 430070China MAO Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products Huazhong Agricultural UniversityWuhan 430070China Department of Pharmacology and Toxicology Faculty of Veterinary MedicineUniversidad Complutense de Madrid(UCM)And Research Institute Hospital 12 de Octubre(i+12)Madrid 28040Spain

In recent years,growing awareness of the role of oxidative stress in brain health has prompted antioxidants,especially dietary antioxidants,to receive growing attention as possible treatments strategies for patients with neurodegenerative diseases(NDs).The most widely studied dietary antioxidants include active substances such as vitamins,carotenoids,flavonoids and polyphenols.Dietary antioxidants are found in usually consumed foods such as fresh fruits,vegetables,nuts and oils and are gaining popularity due to recently growing awareness of their potential for preventive and protective agents against NDs,as well as their abundant natural sources,generally non-toxic nature,and ease of long-term consumption.This review article examines the role of oxidative stress in the development of NDs,explores the‘two-sidedness’of the blood-brain barrier(BBB)as a protective barrier to the nervous system and an impeding barrier to the use of antioxidants as drug medicinal products and/or dietary antioxidants supplements for prevention and therapy and reviews the BBB permeability of common dietary antioxidant suplements and their potential efficacy in the prevention and treatment of NDs.Finally,current challenges and future directions for the prevention and treatment of NDs using dietary antioxidants are discussed,and useful information on the prevention and treatment of NDs is provided.

关键词： Dietary antioxidant supplements Oxidative stress Blood-brain barrier Neurodegenerative diseases Vitamins Carotenoids Flavonoids Polyphenols

Clinical Profiles at the Time of Diagnosis of SARS-CoV-2 Infection in Costa Rica During the Pre-vaccination Period Using a Machine Learning Approach

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Phenomics 2022年第5期2卷 312-322页

作者： Jose arturo Molina-Mora Alejandra González Sergio Jiménez-Morgan Estela Cordero-Laurent Hebleen Brenes Claudio Soto-Garita Jorge Sequeira-Soto Francisco Duarte-martínez Centro de Investigación en Enfermedades Tropicales(CIET)and Facultad de Microbiología Universidad de Costa RicaSan José2060Costa Rica Instituto Costarricense de Investigación y Enseñanza en Nutrición y Salud(INCIENSA) Tres Ríos 30301Costa Rica Escuela de Medicina Universidad de Costa RicaSan José2060Costa Rica

The clinical manifestations of COVID-19,caused by the SARS-CoV-2,define a large spectrum of symptoms that are mainly dependent on the human host conditions.In Costa Rica,more than 169,000 cases and 2185 deaths were reported during the year 2020,the pre-vaccination period.To describe the clinical presentations at the time of diagnosis of SARS-CoV-2 infection in Costa Rica during the pre-vaccination period,we implemented a symptom-based clustering using machine learning to identify clusters or clinical profiles at the population level among 18,974 records of positive cases.Profiles were compared based on symptoms,risk factors,viral load,and genomic features of the SARS-CoV-2 sequence.A total of 18 symptoms at time of diagnosis of SARS-CoV-2 infection were reported with a frequency>1%,and those were used to identify seven clinical profiles with a specific composition of clinical manifestations.In the comparison between clusters,a lower viral load was found for the asymptomatic group,while the risk factors and the SARS-CoV-2 genomic features were distributed among all the clusters.No other distribution patterns were found for age,sex,vital status,and hospitalization.In conclusion,during the pre-vaccination time in Costa Rica,the symptoms at the time of diagnosis of SARS-CoV-2 infection were described in clinical profiles.The host co-morbidities and the SARS-CoV-2 genotypes are not specific of a particular profile,rather they are present in all the groups,including asymptomatic cases.In addition,this information can be used for decision-making by the local healthcare institutions(first point of contact with health professionals,case definition,or infrastructure).In further analyses,these results will be compared against the profiles of cases during the vaccination period.

关键词： COVID-19 Costa Rica Machine learning Diagnosis SARS-CoV-2 Clinical profiles

Role of Reactive Oxygen Species in the Initiation of Plant Retrograde Signaling

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Phyton-International Journal of Experimental Botany 2022年第5期91卷 905-913页

作者： Eduardo-Antonio Trillo-Hernández arturo Duarte Sierra martín Ernesto Tiznado-Hernández Centro de Investigación en Alimentación y Desarrollo A.C.Tecnología de Alimentos de Origen VegetalLaboratorio de Fisiología y Biología Molecular de PlantasHermosillo83304México Department of Food Science and Plant Research and Innovation Center Laval UniversityQuebecQCG1V 0A6Canada

The interaction between the nucleus and the different organelles is important in the physiology of the plant.Reac-tive oxygen species(ROS)are a by-product of the oxidation of organic molecules to obtain energy by the need to carry out the electron transfer between the different enzymatic complexes.However,they also have a role in the generation of what is known as retrograde signaling.This signal comes from the different organelles in which the oxidation of molecules or the electron transference is taking place such as mitochondria and chloroplasts.Furthermore,ROS can also induce the release of signals from the apoplast.It seems that these signals plays a role communicating to the nucleus the current status of the different parts of the plant cell to induce a changes in gene expression.In this review,the molecular mechanism of ROS retrograde signaling is described.

关键词： Reactive oxygen species retrograde signaling mitochondria chloroplast

Canola and Oat Forage Potential Evaluation in Four Early Planting Dates

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Phyton-International Journal of Experimental Botany 2019年第4期88卷 435-448页

作者： Juan Isidro Sánchez-Duarte David Guadalupe Reta-Sánchez JoséAntonio Cueto-Wong arturo Reyes-González Esmeralda Ochoa-martínez Campo Experimental La Laguna Instituto Nacional de Investigaciones ForestalesAgrícolas y Pecuarias(INIFAP).Blvd.JoséSantos Valdez 1200 Pte.Col.CentroMatamorosCoahuilaCP 27440México

Canola and oat forage potential may be affected by climatic conditions when sown early.The objective of this study was to evaluate the forage canola and oat potential in four early sowing dates(September 11 and 25;October 9 and 23)during the 2012-2013 and 2013-2014 cycles in Matamoros,Coahuila,Mexico.Growth cycle duration,chemical composition,dry matter(DM),crude protein(CP),and net energy for lactation(NEL)yields were determined.High temperatures and long photoperiods affected crops seeded on September 11,accelerating growth and reducing canola(26.6%-31.7%)and oat(15.8%)DM yields.As of September 25,canola cv IMC 205 reached DM yields(7746 kg ha^(-1)-9276 kg ha^(-1))similar to those obtained by oat(8115 kg ha^(-1)-9507 kg ha^(-1)),while canola cv Hyola 401 obtained such yields only until October 23.Canola chemical composition was better than that found in oat,with higher CP,but lower acid detergent fiber(ADF)and neutral detergent fiber(NDF)contents.Canola equaled oat CP yields(972 kg ha^(-1)-1215 kg ha^(-1))in the first sowing date,while in the other three other canola sowings reached higher yields(1193 kg ha^(-1)-1889 kg ha^(-1)).As for NEL yields,no difference was observed between both species.The best sowing date for canola is from September 25 on,with CP production advantages over oat.

关键词： Avena sativa L. Brassica napus L.var.oleifera chemical composition dry matter yield nutrients

Atypical Variations of Water Conductivity Prior to Tectonic Earthquakes

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International Journal of Geosciences 2015年第12期6卷 1367-1385页

作者： Fidel martínez-García arturo Colín-Cruz Salvador Adame-martínez Jorge J. Ramírez-García Center of Proposed Drafts of the South Pacific Federal Electricity Commission Cuernavaca Morelos Mexico State Mexico Faculty of Chemistry Autonomous University of Mexico State Toluca de Lerdo Mexico State Mexico Faculty of Urban and Regional Planning Autonomous University of Mexico State Toluca de Lerdo Mexico State Mexico

Within the framework of precursor events related to earthquakes, this paper analyzes the possible effect on the aquatic environment of the surrounding energy that accompanies earthquakes, particularly in the area where oceanic and continental plates collide (Cocos Plate and North American Plate, south of Mexico). As a preamble, the types of precursor events, characteristics, and their possible origin are described. A project was designed under the assumption that in areas with high frequency and intensity seismicity there is an electrical and electromagnetic potential promoter which is detectable and assessable indirectly by measuring water conductivity behavior, which also may have atypical variations of data;the outcome of intensive conductivity monitoring in different settings, natural as well as manmade (wellsprings, artesian well and a cistern), are presented herein. The results of the conductivity monitoring for seven months, highlight two patterns in data behavior: one pattern shows the subtle dependence of data behavior on the geographic location of data monitoring instruments, revealing that could have a slight relationship between areas with increased seismic frequency and intensity and the presence of atypical conductivity variations. Another pattern reveals the possible relationship between atypical variations in conductivity and subsequent earthquake events;a total of 241 seismic events were analyzed and 59 of them are provided as evidence related with patterns mentioned.

关键词： Earthquakes Precursor Events Natural Water Conductivity Subduction Plates Cocos Plate Electromagnetic Fields Earth’s Electromagnetic Pulses

Polymorphisms in oxidative pathway related genes and susceptibility to inflammatory bowel disease

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World Journal of Gastroenterology 2017年第47期23卷 8300-8307页

作者： nezha Senhaji Sellama Nadifi Younes Zaid Aurora Serrano Daniel arturo Leon Rodriguez Nadia Serbati Mehdi Karkouri Wafaa Badre Javier martín Laboratory of Genetic and Molecular Pathology Faculty of Medicine and Pharmacy of CasablancaHassanⅡUniversity Mohammed VI University of Health Sciences Instituto de Parasitología y Biomedicina López-Neyra Consejo Superior de Investigaciones Científicas Department of Pathology CHU Ibn Rochd Department of Gastroenterology CHU Ibn Rochd

AIM To investigate whether common variants in the oxidative pathway genes influence inflammatory bowel disease(IBD) risk among Moroccan patients. METHODS The distribution of(TAAA)n_rs12720460 and(CCTTT)n_rs3833912 NOS2 A microsatellite repeats, HIF-1 A_rs11549467 and NFKB1-94 ins/delA TTG_rs28362491 was analyzed in 507 subjects grouped in 199 IBD and 308 healthy controls. Genotyping was performed withpolymerase chain reaction-fluorescent method and the TaqMan~? allelic discrimination technology.RESULTS The allele and genotype frequencies of HIF1 A_ rs11549467, NFKB1_rs28362491 and NOS2 A_(TAAA)n did not differ significantly between patients and controls. Analysis of NOS2 A_(CCTTT)n markers evidenced differences between patients and healthy controls. A preferential presence of the(CCTTT)8(P = 0.02; OR = 1.71, 95%CI: 1.07-2.74),(CCTTT)14(P = 0.02; OR = 1.71, 95%CI: 1.06-2.76) alleles in IBD,(CCTTT)8(P = 0.008; OR = 1.95, 95%CI: 1.17-3.23) in CD and(CCTTT)7(P = 0.009; OR = 7.61, 95%CI: 1.25-46.08),(CCTTT)11(P = 0.05; OR = 0.51, 95%CI: 0.25-1.01),(CCTTT)14(P = 0.02; OR = 2.05, 95%CI: 1.07-3.94),(CCTTT)15(P = 0.01; OR = 2.25, 95%CI: 1.16-4.35) repeats in UC patients indicated its possible association with higher disease risk which need to be confirmed in a larger sample size. CONCLUSION Our results suggest that the NOS2 A_(CCTTT)n gene variations may influence IBD susceptibility in the Moroccan population.

关键词： HIF1A NFKB1 NOS2A Inflammatory bowel disease Moroccan patients

Laparoscopic Trainer with Pneumoperitoneum

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Surgical Science 2012年第10期3卷 499-502页

作者： José L. Ortiz Simón arturo Minor martínez Neftalí Prado Coronado Ricardo Ordorica Flores Bioelectronics Section Center for Research and Advanced Studies of the IPN México DF México Department of Electrical and Electronics Engineering Technological Institute of Nuevo Laredo Nuevo Laredo México Pediatrics Section Federico Gómez Children’s Hospital México DF México

The development of skills and abilities in laparoscopy is directly related to the use of trainers. The trainer should model the patient with all its natural complexities as closely as possible. In this article we propose a system for training the establishment of pneumoperitoneum executing the basic tasks to create the workspace in the trainer, the insertion of primary umbilical trocar and simulate some of the everyday problems in surgery. Materials and Methods. A group of electrical with biomedical engineers and laparoscopic surgeons developed a physical trainer that allows implementing the pneumoperitoneum. The system uses pneumatic electro valves that are controlled with a dedicated microprocessor. The user can program the system to set the parameters of the pneumoperitoneum. Results. This new trainer facilitated the programming of right values of parameters to distend the abdominal cavity according a specific clinical case. The model developed enables the trainee to consolidate his knowledge on establishing the parameters required within clinical practice, as well as the entry techniques. Conclusions. A new physical model for laparoscopic training was designed. The system enables the laparoscopic surgeon to set the parameters for establishing the workspace according to the clinical case. The trainer allows the surgeon to train in the Hasson technique for the introduction of the first trocar, as well as the placement of the rest of surgical instruments with video assistance. We think this new trainer system will help minimize entry-related injuries.

关键词： Laparoscopy Trainer Pneumoperitoneum

Morphometric, Physicochemical, Thermal, and Rheological Properties of Rice (Oryza sativaL.) Cultivars Indica ×Japonica

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Food and Nutrition Sciences 2014年第3期5卷 271-279页

作者： Laura Elizabeth Morales-martínez Luis arturo Bello-Pérez Mirna María Sánchez-Rivera Elsa Ventura-Zapata Antonio Ruperto Jiménez-Aparicio Centro de Desarrollo de Productos Bióticos del IPN Yautepec México.

The anther culture technical was applied to produce haploid lines of rice (Oryza sativa L.). The hybrids (K/ A92VM061, K/A92VM067, K/A92VM0611, K/A92VM719, K/A92VM720 and K/A92VM721) were obtained in order to generate new varieties from Indica and Japonica cultivars. Morphometric parameters of the grains were evaluated by image analysis. Flours were prepared from the whole rice grains and physicochemical, thermal and rheological properties, X-ray diffraction pattern and evaluation of color using the CIELAB system were assessed. The hybrids lines showed long (061, 611, 721), medium (719 and 720) and short (067) grains. The rice samples presented lipids (2.6% - 3.2%), protein (11% - 15%), total dietary fiber (8.4% - 10.2%), total starch (65% - 74%) and apparent amylose (5% - 32%) contents. Gelatinization temperature (Tp) was found in the range of 66.1℃ - 79.4℃ with enthalpy (ΔH) value between 3.4 - 8.1 J/g. The retrogradation parameters (temperature and ΔH) were lower than those for gelatinization in all samples. The rice samples presented A-type X-ray diffraction pattern. Rice pastes showed a non-Newtonian behavior and the brightness (L*) characterize the color of the samples. Hybrid rice grains presented morphometric properties more similar to Japonica than Indica variety. Rice hybrid had higher protein content than Indica variety. Apparent amylose, viscosity and gelatinization temperature varied significantly among hybrids and varieties.

关键词： Brown Rice Hybrid Grains Morphometric Parameters Gelatinization Temperature Flow Behavior Pasting Viscosity

Effect of Water Regimes on Dietary Fiber, Polyphenols and Antioxidant Capacity of Black and Pinto Beans

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Agricultural Sciences 2014年第4期5卷 342-352页

作者： Maribel Ovando-martínez Salvador Horacio Guzmán-Maldonado Senay Simsek Luis arturo Bello-Pérez Perla Osorio-Díaz CEPROBI Instituto Politécnico Nacional Yautepec México CEPROBI Instituto Politécnico Nacional Yautepec México Department of Plant Sciences North Dakota State University Fargo USA Department of Plant Sciences North Dakota State University Fargo USA Unidad de Biotecnología del Campo Experimental Bajío INIFAP Celaya México

Beans are rich in dietary fiber and polyphenols;however, growing conditions may affect the occurrence of these components. The effect of irrigation and rain fed conditions on dietary fiber, indigestible fraction, polyphenols and antioxidant capacity of Black 8025 and Pinto Durango bean cultivars grown in Mexico have been determined. Total dietary fiber decreased in beans grown under rain fed conditions compared to those grown under irrigation. The water regimes had an effect on the total indigestible fraction for Black 8025 bean. The extractable polyphenols were affected by the water regimes, while the antioxidant capacity of extractable and non-extractable polyphenols was dependent on the bean variety. Cooking the beans altered the extractable and non-extractable polyphenols and the antioxidant capacity. Also, the antioxidant properties and some extend, the digestibility of non-digestible carbohydrates of beans were affected by water regimes. This information could be taken into account for dry bean breeding programs to improve the nutritional quality of beans.

关键词： Water Regimes Dietary Fiber Indigestible Fraction Polyphenols Antioxidant Capacity Cooking