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Fish Nutrition Additives in SHK-1 Cells: Protective Effects of Silymarin

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Advances in Bioscience and Biotechnology 2016年第2期7卷 55-62页

作者： Rodrigo Sanchez Pamela Olivares Erico Carmona Allisson Astuya Hector herrera Jorge Parodi Laboratorio Fisiología de la Reproducción Escuela de Medicina Veterinaria Núcleo de Investigación en Producción Alimentaria Facultad de Recursos Naturales Universidad Católica de Temuco Temuco Chile Empresa Vitapro Chile Castro Región de Los Lagos Chile Grupo de Genotoxicología Escuela de Medicina Veterinaria Núcleo de Estudios Ambientales Facultad de Recursos Naturales Universidad Católica de Temuco Temuco Chile Laboratory of Cell Culture and Marine Genomics Marine Biotechnology Unit Faculty of Natural and Oceanographic Sciences University of Concepcion and Sur-Austral COPAS Program University of Concepcion Concepción Chile

In nutrition for productive species, additives play an important role in boosting physiological processes. Only in recent years studies include models of the effects on fish cells of these additives. We observed effects of silymarin, a compound highly utilized in aquaculture. The cell line SHK-1 was used derived from the upper liver of the Atlantic salmon as a biological model. Samples were exposed to silymarin in incrementing time and concentrations, to evaluate by MTT and number of cells, the effects on cell viability. Also, oxidative stress models were used to find the protector effects of silymarin against these agents. Our data indicate that a dose of 100 ppm of silymarin is sufficient to stimulate cellular proliferation. Cultures were exposed to high glucose (15 mM) or H2O2 (0.1 mM) in presence of or absence of silymarin at 100 ppm. We observed that the toxic effects of both compounds were blocked by the presence of silymarin. Our results indicate that it is important to evaluate additive effects at a cellular level. Also, silymarin does have proliferative effects, and protect against cellular injury in our models. Our study helps to generate more rational applications of additives in the industry and presents new challenges in order to better manipulate the model in the laboratory, allowing us to obtain new evidence regarding the microalgae’s biology through in vitro studies.

关键词： Fish Nutrition Silymarin Cell Cultures

Local Changes in Chromatin Accessibility and Transcriptional Networks Underlying the Nitrate Response in Arabidopsis Roots

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Molecular Plant 2019年第12期12卷 1545-1560页

作者： Jose M.Alvarez Tomas C.Moyano Tao Zhang Diana E.Gras Francisco J.herrera Viviana Araus Jose AQ'Brien Laura Carrillo Joaquin Medina Jesus Vicente-Carbajosa Jiming Jiang Rodrigo A.Gutierrez Pontificia Universidad Catolica de Chile SantiagoChile Yangzhou University YangzhouChina Instituto de Agrobiotecnologia del Litoral CONICETSanta FeArgentina University of California BerkeleyCAUSA Trancura Biosciences Inc.San FranciscoCA 94158USA Centro de Biotecnología y Genómica de Plantas(CBGP UPM-INIA)Universidad Politecnica de Madrid(UPM)Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria(INIA)Campus de Montegancedo28223-Pozuelo de AlarcóMadridSpain Department of Horticulture University of Wisconsin-MadisonMadisonWI 53706USA Department of Plant Biology and Horticulture Michigan State UniversityMI 48824USA

Transcriptional regulation,determined by the chromatin structure and regulatory elements interacting at pro-moter regions,is a key step in plant responses to environmental ***(NO3-)is a nutrient signal that regulates the expression of hundreds of genes in Arabidopsis ***,we integrate mRNA sequencing,genome-wide RNA polymeraseⅡ(RNPⅡ),chromatin immunoprecipitation sequencing,and DNase Sequencing datasets to establish the relationship between RNPⅡoccupancy and chromatin accessibility in response to NO3-treatments in Arabidopsis *** footprinting allowed us to identify in vivo regula-tory elements controlling gene expression in response to ***3--modulated transcription factor(TF)footprints are important for a rapid increase in RNPⅡoccupancy and transcript accumulation over *** mapped key TF regulatory interactions and functionally validated the role of NAP,an NAC-domain containing TF,as a new regulatory factor in *** together,our study provides a comprehensive view of transcriptional networks in response to a nutrient signal in Arabidopsis roots.

关键词： nitrate transcriptional regulation footprinting RNA polymeraseⅡ regulatory networks

Improved method for XPS and ARXPS data fitting

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Improved method for XPS and ARXPS data fitting

Seismic response of high-rise steel framed buildings with Chevron-braced designed according to Venezuelan codes

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作者： A. herrera-Gomez J. Muoz-Flores CINVESTAV-Unidad Queretaro Queretaro 76230Mexico Departamento de Física CINVESTAVDistrito Federal 07360Mexico

X-Ray Photoelectron Spectroscopy can provide chemical and, if acquired at different angles, depth-profile information. Data-fitting is employed to quantify the various peaks contributing to a core-level spectrum. In most cases, each peak corresponds to a particular chemical environment. When the binding energy difference among the peaks is equal or larger than the width of the peaks, the quantification is straightforward. For cases in which the binding energy is smaller, the accuracy on the determination of the area, width, and center of the peaks becomes much more dependent on the noise level of the data. For quantitative studies, it is fundamental to employ data analysis methods that are the least sensible to noise. Sequential-fitting is a common practice on ARXPS data analysis. It consist on first estimating the center and width of the peaks from the data acquired at one of the angles, and then using those parameters as a starting guess for fitting the data for the rest of the angles. An improvement of this method consists on averaging the centers and widths of the peaks obtained at the different angles, and then employing these values to assess the areas of the peaks for each angle. The full-use of the combined information contained in the data-set is optimized by the simultaneous fitting method. It consists of the assessment of the center and width of the peaks by fitting the data at all the angles simultaneously. Computer-generated data was employed to compare the sensitivity regarding to noise between the sequential, averaged-sequential, and simultaneous fitting methods. It will be shown that the latter is significantly more robust and could provide reliable results even for very noisy data. Among the examples of the application of the simultaneous fitting method that will be presented is 1) the analysis of the O 1s and N 1s XPS data from hafnium oxynitride grown on silicon oxynitride nanofilms and 2) the discrimination of the sp2 and sp3 contributions to the

关键词： Simultaneous fitting Sequential fitting, Robust method, Noise, XPS, ARXPS, Data fitting

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Natural Science 2012年第8期4卷 694-698页

作者： Ronald Ugel Juan Carlos Vielma Reyes herrera Sigrit Perez Alex Barbat Senior Technical School of Roads Canals and Ports Engineers of Barcelona Technical University of Catalonia. Barcelona Spain Structural Engineering Department School of Civil Engineering Lisandro Alvarado University. Barquisimeto Venezuela

The object of this study is to determine the seismic response of regular high-rise steel buildings with chevron-braced frames. Mechanics models of three buildings of 14, 18 and 20 stories are studied, all of them with similar geometric characteristics in plant and elevation. These models are realized using prescriptions and parameters from venezuelan design codes. The seismic action is carry on through varius synthetic design spectrum compatible accelerograms defined by the seismic codes in this study, with three levels of intensity corresponding to three specific Limit States. Dynamic analysis is used to compute parameters of ductility, over strength and maximum displacements. From these results it can be concluded that chevron-braced frames presented a good overall performance and non V-braced frames show greater damage due to dynamic actions, validating non linear dynamic analysis as a very powerful tool to seismic-resistance design and chevron-braced frames as a very useful choice in improving the response of tall steel structures. since this lateral bracing system is absent from Venezuelan seismic codes.

关键词： Framed Steel Buildings Chevron Braced Frames Non Linear Analysis Over Strength Seismic Response

Dystrophic Calcinosis in the Hands of a Patient with Rheumatoid Arthritis and Secundary Sjogren’s Syndrome

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Open Journal of Rheumatology and Autoimmune Diseases 2013年第1期3卷 56-58页

作者： Daniel Jaramillo-Arroyave Gerardo Quintana Federico Rondon-herrera Antonio Iglesias-Gamarra Internal Medicine RheumatologyDepartment of Internal MedicineRheumatology UnitUniversidad Nacional de ColombiaBogotáColombia

Salts of calcium phosphate and inorganic phosphate are normally found in serum and extracellular fluids, balancing through poorly understood factors that prevent abnormal tissue deposition of these minerals. However, in those tissues that are injured, especially due to chronic inflammatory processes, a predisposition to the deposition of these minerals is developed, triggering what has been called Dystrophic Calcinosis (DC), common in different Connective Tissue Diseases (CTD), especially dermatomyositis and scleroderma, but there is no a frecuent association with diseases like Rheumatoid Arthritis (RA) and Sj?gren Syndrome (SS). We report a case of a female patient of 63 years old with RA and Secundary SS who presents with DC in the hands and no evidence of other connective tissue.

关键词： Dystrophic Calcinosis Rheumatoid Arthritis Sjogren Syndrome

Assessing the Crop Growing Period According to the Climate Change Forecasts for Marina Baixa (SE Spain)

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Agricultural Sciences 2015年第9期6卷 1079-1088页

作者： Mario herrera Hassane Moutahir Carlos Alberto González Esteban Chirino Juan Bellot Department of Life Sciences University State Amazonia Puyo Ecuador Department of Ecology University of Alicante Alicante Spain Multidisciplinary Institute for Environmental Studies “Ramón Margalef” University of Alicante Alicante Spain AdMobilze.Computer Vision Engineer Miami FL USA Faculty of Natural Resources Polytechnic Higher School of Chimborazo (ESPOCH) Riobamba Ecuador

The present work aims to assess the likely effects of climate change on the length of growing period (LGP) of crops in Marina Baixa (SE, Spain). LGP can be assessed by a balance between preci- pitation and reference evapotranspiration. Less rainfall and an increased evapotranspiration, forecast by Global Climate Models (GCMs), are considered as a high risk for agriculture. This area is located in a semiarid climate region where water is a very limited resource. It is a typical example of areas where the agricultural sector has to compete for water with the tourism industry. In this context, by using observed and projected precipitation data set (model HadCM3, Scenario A2), calculating reference evapotranspiration (ETo), and applying the frequency analysis of a probability-type method, we estimated the growing period length in the observed period (1961-1990) and three 30-year future periods (2011-40, 2041-70 and 2071-99) in the study area. The results show a drop in annual precipitations (-?30%) and an increased ETo (+18%) towards the end of this century with respect to the observed period (mean annual rainfall: 356 mm;mean ETo: 1476 mm). The results also show a decrease in the number of decades (10 days) when precipitation exceeds half of the ETo, which means shorter growing periods as the 21st century advances. This expected reduction in growing period length towards the end of the present century will imply that many rainfed crops, like olives, almonds and cereals, will require a higher irrigation water supply to maintain suitable growth and performance levels. The results are an early warning to manage water resources in Marina Baixa in a sustainable way.

关键词： Climate Change Growing Period Frequency Analysis Semiarid Mediterranean

Biofilm and Helicobacter pylori:From environment to human host

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World Journal of Gastroenterology 2014年第19期20卷 5632-5638页

作者： Apolinaria García María José Salas-Jara Carolina herrera Carlos González Laboratorio de Patogenicidad Bacteriana Departamento de MicrobiologíaFacultad de Ciencias BiológicasUniversidad de ConcepciónConcepción 4030000Chile

Helicobacter pylori(***)is a Gram negative pathogen that selectively colonizes the human gastric *** 50%of the world population is infected with *** reaching up to 90%of infected individuals in developing *** the increased impact upon public health care,its reservoir and the transmission pathway of the species has not been clearly established *** studies allowed the detection of *** in various aquatic environments,even forming biofilm in tap water distribution systems in several countries,suggesting a role of water as a possible reservoir of the *** persistence of human infection with *** and the resistance of clinical isolates to commonly used antibiotics in eradication therapy have been related to the genetic variability of the species and its ability to develop biofilm,demonstrated both in vivo and in vitro ***,during the last years,experimental work with this pathogen has been focused in the search for biofilm inhibitors and biofilm destabilizing ***,only two *** biofilm disrupting agents have been successfully used:Curcumin-a natural dye-and N-acetyl cysteine-a mucolytic agent used in respiratory *** main goal of this review was to discuss the evidences available in the literature supporting the ability of *** to form biofilm upon various surfaces in aquatic environments,both in vivo and in *** results published and our own observations suggest that the ability of *** to form biofilm may be important for surviving under stress conditions or in the spread of the infection among humans,mainly through natural water sources and water distribution systems.

关键词： Helicobacter pylori Biofilm,Water Infection

Esophagogastric Reconstruction in Cobra-Head Shape with Toupet-Like Partial Anti-Reflux Technique for Resection of Proximal Gastric Tumors. Experience with Three Cases from a Non-Asian Population

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Open Journal of Gastroenterology 2023年第4期13卷 149-160页

作者： Alberto M. León-Takahashi Ana P. Meléndez-Fernández Leonardo S. Lino-Silva Horacio N. López-Basave Rosa Angelica Salcedo Hernandez César Zepeda-Najar Ángel herrera-Gómez Surgical Oncology National Cancer Institute (México) Mexico City Mexico Surgical Pathology National Cancer Institute (México) Mexico City Mexico Surgical Oncology ángeles Hospital Tijuana Mexico

Background: Proximal gastrectomy is a rarely performed procedure but a feasible option in benign tumors and malignant neoplasms in the proximal third of the stomach since novel options of reconstructions are available nowadays with fewer long-term sequels. Methods: Report of three cases of proximal gastric gastrointestinal stromal tumors (GIST), with a description of its presentation, histological characteristics, and follow-up after being treated with proximal gastrectomy with cobra head reconstruction. Results: Case 1: A 62-year-old woman with epigastric pain of four months with endoscopic evidence of a cardia GIST. The surgery was performed without complications. The histopathological report confirmed a fusiform GIST of 3.2 × 3 × 2.5 cm, stage IA. No adjuvant treatment was considered. An esophagogram showed no evidence of reflux and no stenosis, and no disease recurrence after 40-months follow-up. Case 2: A 66-year-old woman with dyspepsia and a palpable tumor in the epigastrium. The surgery was performed without complications. The pathology report confirmed a proximal gastric GIST of 13 × 8 × 7 cm, staged II. She received adjuvant treatment with imatinib for 36 months without recurrence and no reflux or stenosis. Case 3: A 55-year-old woman with intermittent hematemesis and right subscapular pain. The surgery was performed without complications. The histopathological report concluded that a GIST tumor of the cardia, 1.4 × 1.2 cm, staged IA. She was left in observation. At a 6-month follow-up, she does not report dysphagia, reflux, or stenosis, and no locoregional recurrence. Conclusions: Open and laparoscopic proximal gastrectomy is a safe therapeutic option for GIST. Furthermore, the reconstruction of the esophagus-gastro anastomosis in the cobra head after proximal gastrectomy is feasible and secure in our population, with good functional results in a short follow-up.

关键词： GIST Gastric Cancer Laparoscopy Proximal Gastrectomy Cobra Head Reconstruction

Knowledge arising from long-term research of variable retention harvesting in Tierra del Fuego: where do we go from here?

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Ecological Processes 2019年第1期8卷 318-333页

作者： Guillermo J.Martínez Pastur Yamina M.Rosas Mónica Toro Manríquez Alejandro Huertas herrera Juan A.Miller Juan M.Cellini Marcelo D.Barrera Pablo L.Peri María V.Lencinas Centro Austral de Investigaciones Científicas(CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 200(9410)UshuaiaTierra del FuegoArgentina Universidad Nacional de la Plata(UNLP) Calle 7 e/47 y 48(1900)La PlataBuenos AiresArgentina Instituto Nacional de Tecnología Agropecuaria(INTA) Universidad Nacional de la Patagonia Austral(UNPA)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)cc 332(9400)Río GallegosSanta CruzArgentina

Nothofagus pumilio forests in Tierra del Fuego are the southernmost forests in the world,where extreme climate conditions represent a challenge to attain sustainable forest *** forestry was proposed as an alternative to increase the species conservation in managed ***,we synthetized results related to the implementation of a variable retention harvesting based on a combination of aggregate patches and dispersed retention during the last 18 years comparing with other silviculture proposals(e.g.,shelterwood cuts)and control treatments(primary unmanaged forests).We summarized the results for(i)sawmill operations,(ii)timber yield,(iii)overstory stability,(iv)forest structure,(v)microclimate and natural cycles,(vi)natural regeneration dynamics(flowering,seeding,foraging,recruitment,growth,and mortality),and(vii)biodiversity(mammals,understory plants,mistletoes,birds,arthropods,mosses,lichens,and fungi).In general,aggregate patches maintained forest structure and micro-environmental variables,and slightly increased biodiversity and forest reproduction variables compared to unmanaged primary *** the contrary,dispersed retention decreased forest structure variables and greatly increased biodiversity(richness and abundance)when it was compared to unmanaged primary *** conditions are influenced by variable retention harvesting,but direction and magnitude of the effect depend and differ according to retention *** this,biodiversity taxa greatly differed among groups depending on retention *** general,the species assemblages in aggregate patches were similar to those found in primary unmanaged forests,while they were significantly modified in the dispersed *** occurred due to(i)local extinction of some original species,(ii)the introduction of native species from the surrounding environments,or(iii)the invasion of exotic *** silvicultural method has been a useful tool to conserve biodiversity and ec

关键词： Aggregate patches Dispersed retention Biodiversity conservation Long-term sustainability Timber production