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Redox Regulation of Glycogen Biosynthesis in the Cyanobacterium Synechocystis sp. PCC 6803： Analysis of the AGP and Glycogen Synthases

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Molecular Plant 2014年第1期7卷 87-100页

作者： Sandra diaz-Troya luis Lopez-Maury Ana Maria Sanchez-Riego Miguel Roldan Francisco J. Florencio Instituto de Bioquimica Vegetal y Fotosintesis Universidad de Sevilla-CSIC Americo Vespucio 49 E-41092 Sevilla Spain

Glycogen constitutes the major carbon storage source in cyanobacteria, as starch in algae and higher plants. Glycogen and starch synthesis is linked to active photosynthesis and both of them are degraded to glucose in the dark to maintain cell metabolism. Control of glycogen biosynthesis in cyanobacteria could be mediated by the regulation of the enzymes involved in this process, ADP-glucose pyrophosphorylase （AGP） and glycogen synthase, which were identified as putative thioredoxin targets. We have analyzed whether both enzymes were subjected to redox modification using purified recombinant enzymes or cell extracts in the model cyanobacterium Synechocystis sp. PCC 6803. Our results indicate that both AGP and glycogen synthases are sensitive to copper oxidation. However, only AGP exhibits a decrease in its enzymatic activity, which is recovered after reduction by DTT or reduced thioredoxin （TrxA）, suggesting a redox control of AGP. In order to elucidate the role in redox control of the cysteine residues present on the AGP sequence （C45, C185, C320, and C337）, they were replaced with serine. All AGP mutant proteins remained active when expressed in Synechocystis, although they showed different electrophoretic mobility profiles after copper oxidation, reflecting a complex pattern of cysteines interaction.

关键词： cyanobacteria glycogen Synechocystis thioredoxin redox regulation.

Ni-based catalysts obtained from perovskites oxides for ethanol steam reforming

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燃料化学学报 2018年第11期46卷 1332-1341页

作者： Fabiola Nerina Agüero jose Antonio Alonso Maria Teresa Fernández-Díaz luis Eduardo Cadus Instituto de Investigaciones en Tecnología Química(INTEQUI) UNSL-CONICETAlmirante Brown 14555700 San LuisArgentina Instituto de Ciencia de Materiales de Madrid Consejo Superior de Investigaciones CientíficasCantoblanco28049 MadridSpain Institut Laue-Langevin B.P.156F-38042 Grenoble Cedex 9France

Perovskites as host structures of cations were used in order to generate in situ active and stable catalysts for ethanol steam reforming. For this purpose,La_(1-x)Mg_xAl_(1-y)Ni_yO_3(x = 0.1; y = 0,0.1,0.2,0.3) perovskites were synthetized by the citrate *** segregation is evident for a substitution level higher than 0. 2. The segregation of Ni as NiO generated species interacts with different metal-support after the reduction step. The y = 0.1 catalyst presents the highest H_2 yield value about 85% during reaction time,with low mean values of CH_4 and CO selectivities of 3.4% and 11%,respectively and a low carbon formation. The better performance of y = 0.1 catalyst could be attributed to the minor proportion of segregated phases,thus a controlled expulsion of Ni is successfully reached.

关键词： perovskites catalyst design ethanol steam reforming

Role of robotic-assisted pancreatic surgery:lessons learned from our initial experience

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Hepatobiliary & Pancreatic Diseases International 2017年第6期16卷 652-658页

作者： Emilio Vicente Yolanda Quijano Benedetto Ielpo Hipolito Duran Eduardo diaz Isabel Fabra luis Malave Riccardo Caruso General Surgery Department Sanchinarro University Hospital San Pablo University CEU Madrid Spain

BACKGROUND:Minimally invasive surgery has achieved worldwide acceptance in various fields, however, pancreatic surgery remains one of the most challenging abdominal procedures. In fact, the indication for robotic surgery in pancreatic disease has been controversial. The present study aimed to assess the safety and feasibility of robotic pancreatic ***:We retrospectively reviewed our experience of robotic pancreatic resection done in Sanchinarro University Hospital. Clinicopathologic characteristics, and perioperative and postoperative outcomes were recorded and ***:From October 2010 to April 2016, 50 patients underwent robotic-assisted surgery for different pancreatic pathologies. All procedures were performed using the da Vinci robotic system. Of the 50 patients, 26 were male and 24 female. The average age of all patients was 62 years. Operative time was 370 minutes. Among the procedures performed were 16 pancreaticoduodenectomies(PD), 23 distal pancreatectomies(DP), 11 tumor enucleations(TE). The mean hospital stay was 17.6 days in PD group, 9.0 days in DP group and 8.4 days in TE group. Pancreatic fistula occurred in 10 cases(20%), 2 after PD, 3 after DP, and 5 after TE. Four patients had postoperative transfusion in PD group and one in DP group. Conversion to open laparotomy occurred in four patients(8%). No serious intraoperative complications were observed. CONCLUSIONS:From our early experience, robotic pancreatic surgery is a safe and feasible procedure. Further experience and follow-up are required to confirm the role of robotic approach in pancreatic surgery.

关键词： robotic surgery pancreatic cancer minimal invasive surgery

Phenotyping for Abiotic Stress Tolerance in Maize

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Journal of Integrative Plant Biology 2012年第4期54卷 238-249页

作者： Benhilda Masuka jose luis Araus Biswanath Das Kai Sonder Jill E.Cairns International Maize and Wheat Improvement Center(CIMMYT) Unit of Plant Physiology Faculty of BiologyUniversity of Barcelona CIMMYT Km 45 Carretera Mexico-Veracruz

The ability to quickly develop germplasm having tolerance to several complex polygenic inherited abiotic and biotic stresses combined is critical to the resilience of cropping systems in the face of climate change. Molecular breeding offers the tools to accelerate cereal breeding; however, suitable phenotyping proto- cols are essential to ensure that the much-anticipated benefits of molecular breeding can be realized. To facilitate the full potential of molecular tools, greater emphasis needs to be given to reducing the within-experimental site variability, application of stress and characterization of the environment and appropriate phenotyping tools. Yield is a function of many processes throughout the plantcycle, and thus integrative traits that encompass crop performance over time or organization level （i.e. canopy level） will provide a better alternative to instantaneous measurements which provide only a snapshot of a given plant process. Many new phenotyping tools based on remote sensing are now available including non-destructive measurements of growth-related parameters based on spectral reflectance and infrared thermometry to estimate plant water status. Here we describe key field phenotyping protocols for maize with emphasis on tolerance to drought and low nitrogen.

关键词： Drought low nitrogen tolerance maize phenotyping spatial variability.

Changes in Cinnamic Acid Derivatives Associated with the Habituation of Maize Cells to Dichlobenil

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Molecular Plant 2011年第5期4卷 869-878页

作者： Hugo Melida Jesus Alvarez jose luis Acebes Antonio Encina Stephen C. Fry Area de Fisiologia Vegetal Facultad de CC Biologicas y Ambientales Universidad de Leon E-24071 Leon Spain Edinburgh Cell Wall Group Institute of Molecular Plant Sciences School of Biological Sciences University of Edinburgh Daniel Rutherford Building The King＇s Buildings Edinburgh EH9 3JH UK

The habituation of cell cultures to cellulose biosynthesis inhibitors such as dichlobenil （DCB） represents a valu- able tool to improve our knowledge of the mechanisms involved in plant cell wall structural plasticity. Maize cell lines habituated to lethal concentrations of DCB were able to grow through the acquisition of a modified cell wall in which cellulose was partially replaced by a more extensive network of arabinoxylans. The aim of this work was to investigate the phenolic metabolism of non-habituated and DCB-habituated maize cell cultures. Maize cell cultures were fed [14C]cinnamate and the fate of the radioactivity in different intra-protoplasmic and wall-localized fractions throughout the culture cycle was analyzed by autoradiography and scintillation counting. Non-habituated and habituated cultures did not markedly differ in their ability to uptake exogenous [14C]cinnamic acid. However, interesting differences were found in the radiolabeling of low- and high-Mr metabolites. Habituated cultures displayed a higher number and amount of radiola-beled low-Mr compounds, which could act as reserves later used for polysaccharide feruloylation. DCB-habituated cultures were highly enriched in esterified [14C]dehydrodiferulates and larger coupling products. In conclusion, an extensive and early cross-linking of hydroxycinnamates was observed in DCB-habituated cultures, probably strengthening their cellulose-deficient walls.

关键词： Cell wall Zea mays maize dichlobenil DCB dehydrodiferulate ferulate cinnamic acid.

New Technologies,Tools and Approaches for Improving Crop Breeding

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Journal of Integrative Plant Biology 2012年第4期54卷 210-214页

作者： Parry, Martin A. J. Wang, Jiankang luis Araus, jose Rothamsted Res Harpenden Herts England Chinese Acad Agr Sci Beijing 100193 Peoples R China Univ Barcelona Barcelona Spain

Most crops were first domesticated about 13 000 to 11 000 years ago. Humans are dependent on crops for survival, and from the beginnings of agriculture have been energetically involved in developing crops that better serve their needs （Allard 1999）. During the last decades breeding has contributed approximately a 50% contribution to increasing the world＇s food crop production. However, plant breeding only began to adopt a scientific approach in the 1900s, when Mendel＇s hybridization experiment was rediscovered. Mendelian genetics and the development of the statistical concepts of randomJzatJon and replication had considerable impact on plant breeding methods （Hallauer et al. 1988）. In spite of the fact that scientific crop breeding has only existed for one century, it is a discipline that is developing very quickly. The major objective of crop breeding programs is to develop new genotypes that are genetically superior to those currently available for specific environments. To achieve this objective, breeders employ a range of selection methods and technologies （Hallauer et al. 1988; Falconer and Mackay 1996; Allard 1999）.

关键词： PLANT breeding PLANT breeders CLIMATIC changes FOOD security EFFECT of drought on plants PLANT genetics NUCLEOTIDE sequence

Benchmarking of two three-dimensional numerical models in time/space domain to predict railway-induced ground vibrations

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Earthquake Engineering and Engineering Vibration 2021年第1期20卷 245-256页

作者： Jesus Fernandez-Ruiz luis E.Medina Rodriguez Pedro Alves Costa Margarita Martinez-diaz University of La Coruna Department of Civil EngineeringCampus de ElvinaLa Coruna 15071Spain University of Porto Faculty of EngineeringRua Dr.Roberto Friass/n Porto4200-465Portugal University of La Coruna Department of Naval and Industrial EngineeringCampus de ElvinaLa Coruna 15071Spain

In the last 30 years,the scientific community has developed and proposed different models and numerical approaches for the study of vibrations induced by railway *** of them are formulated in the frequency/wave number domain and with a 2.5D ***-dimensional numerical models formulated in the time/space domain are less frequently used,mainly due to their high computational ***,these models present very attractive characteristics,such as the possibility of considering nonlinear behaviors or the modelling of excess pore pressure and non-homogeneous and non-periodic geometries in the longitudinal direction of the *** this study,two 3D numerical approaches formulated in the time/space domain are compared and experimentally *** first one consists of a finite element approach and the second one of a finite difference *** experimental validation in an actual case situated in Carregado(Portugal)shows an acceptable fitting between the numerical results and the actual measurements for both ***,there are some differences among *** study therefore includes some recommendations for their use in practical soil dynamics and geotechnical engineering.

关键词： railway vibrations time/space domain 3D numerical model finite difference method implicit finite element method

Prevalence and risk factors of acute-on-chronic liver failure in a single center from Argentina

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World Journal of Hepatology 2016年第34期8卷 1529-1534页

作者： Cristian Dominguez Eugenia Romero Jorgelina Graciano jose luis Fernandez luis Viola Division of Gastroenterology Sanatorio Guemes Centro Integral de Gastroenterología

AIMTo study the prevalence, characteristics, risk factors and mortality at 28 d of acute-on-chronic liver failure (ACLF). METHODSA total of 100 cirrhotic patients admitted to our hospital for more than one day were included during the period between June 2013 and December 2015. We used the European Association for the Study of the Liver-Chronic Liver Failure-Consortium diagnostic criteria for ACLF, considering it as the acute decompensation of cirrhosis associated with the presence of one or more organ failure. For the diagnosis of organic failure the Chronic Liver Failure-Sequential Organ Failure Assessment score was used. Our population was divided into patients with and without ACLF. Clinical characteristics, presence of precipitating events, potential risk factors for developing ACLF and causes of mortality were analyzed. Mortality at 28 d was evaluated. RESULTSTwenty-nine patients (29%) developed ACLF criteria. Alcoholism, detected in 58 patients (58%), was the major etiological agent of cirrhosis. Bacterial infections were recognized as a precipitating event in 41.3% of cases and gastrointestinal bleeding in 27.5%. No precipitating event was identifiable in 27.5% of patients with ACLF. Comparing patients with and without ACLF, statistically significant risk factors were: Child Pugh score 10.2 ± 2.1 vs 8.4 ± 1.6 (P ˂ 0.0001), MELD score 20.7 ± 8.5 vs 12.3 ± 4 (P ˂ 0.0001), presence of ascites 27 (93%) vs 43 (60.5%) (P = 0.001), leukocytosis 15300 ± 8033 per cubic millimeter vs 10770 ± 5601 per cubic millimeter (P ˂ 0.0001), and high plasma levels of C reactive protein values 50.9 ± 46.4 mg/L vs 28.6 ± 23.4 mg/L (P ˂ 0.0019). Mortality rate was 62% (18 patients) vs 5.6% (4 patients), respectively (P CONCLUSIONWe observed that the ACLF is a frequent entity in this group of patients and has a significantly higher mortality rate.

关键词： Acute-on-chronic liver failure Acute liver decompensation Cirrhosis Ascites Mortality

A novel and stretchable carbon-nanotube/Ni@TiO_(2):W photocatalytic composite for the complete removal of diclofenac drug from the drinking water

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Journal of Environmental Sciences 2023年第4期126卷 575-589页

作者： Ernesto Valadez-Renteria Rafael Perez-Gonzalez Christian Gomez-Solis luis Armando diaz-Torres Armando Encinas Jorge Oliva Vicente Rodriguez-Gonzalez Consejo Nacional de Ciencia y Tecnología-División de Materiales Avanzados Instituto Potosino de Investigación Científica y TecnológicaSan Luis Potosí78216México División de Ciencias e Ingenierías Universidad de GuanajuatoLeón 37150México Grupo de Espectroscopia de Materiales Avanzados y Nanoestructurados(GEMANA) Centro de Investigaciones enópticaA.C.Lomas Del CampestreLeón 37150México

We present the structural,morphological and photocatalytic properties of stretchable composites made with carbon nanotubes (CNTs),silicon rubber and Ni@TiO_(2):W nanoparticles(TiWNi NPs) with average size of 37±2 *** images showed that the TiWNi NPs decorated the surface of the CNT fibers,which are oriented in a preferential *** NPs presented a mixture of anatase/rutile phases with cubic *** performance of the TiWNi powders and stretchable composites was evaluated for the photocatalytic degradation of diclofenac (DCF) anti-inflammatory drug under ultraviolet-visible *** results revealed that the maximum DCF degradation percentages were 34.6%,91.9%,97.1%,98.5%and 100%for the CNT composite (stretched at 0%),TiWNi powders,CNT+TiWNi(stretched at 0%),CNT+TiWNi (stretched at 50%) and CNT+TiWNi (stretched at 100%),***,stretching the CNT+TiWNi composites was a good strategy to enhance the DCF degradation percentage from 97.1%to 100%,since stretching created additional defects (oxygen vacancies) that acted as electron sink,delaying the electron-hole recombination,and favors the DCF ***/absorbance measurements confirmed the presence of such ***,the reactive oxygen species (ROS) were determined by the scavenger’s experiments and found that the main ROS were the·OH and O_(2)-radicals,which attacked the DCF molecules,causing their *** results of this investigation confirmed that the stretchable CNT/TiWNi-based composites are a viable alternative to remove pharmaceutical contaminants from water and can be manually separated from the decontaminated water,which is unviable using photocatalytic powders.

关键词： Diclofenac Pharmaceutical contaminant TiO_(2) Carbon nanotubes Stretchable composite Photocatalysis