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Are we giving azathioprine too late? The case for early immunomodulation in inflammatory bowel disease

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World Journal of Gastroenterology 2008年第36期14卷 5512-5518页

作者： María Josefina Etchevers montserrat Aceituno Miquel Sans Department of Gastroenterology Hospital Posadas Buenos Aires Argentina Department of Gastroenterology Hospital Clínic i Provincial/IDIBAPS Barcelona CIBER Enfermedades Hepáticas y Digestivas Spain

Inflammatory bowel disease (IBD) includes two entities, Crohn’s disease and ulcerative colitis. Both are chronic conditions with frequent complications and surgical procedures and a great impact on patient’s quality of life. The thiopurine antimetabolites azathioprine and 6-mercaptopurine are widely used in IBD patients. Current indications include maintenance therapy, steroid-dependant disease, fistula closure, prevention of infliximab immunogenicity and prevention of Crohn’s disease recurrence. Surprisingly, the wide use of immunosuppressants in the last decades has not decreased the need of surgery, probably because these treatments are introduced at too late stages in disease course. An earlier use of immunossupressants is now advocated by some authors. The rational includes: (1) failure to modify IBD natural history of present therapeutic approach, (2) demonstration that azathioprine can induce mucosal healing, a relevant prognostic factor for Crohn’s disease and ulcerative colitis, and (3) demonstration that early immunossupression has a very positive impact on pediatric, recently diagnosed Crohn’s disease patients. We are now awaiting the results of new studies, to clarify the contribution of azathioprine, as compared to infliximab (SONIC Study), and to demonstrate the usefulness of azathioprine in recently diagnosed adult Crohn’s disease patients (AZTEC study).

关键词： Inflammatory bowel disease Crohn's disease Ulcerative colitis Immunosuppressants Azathioprine

Diversity of plants and mammals as indicators of the effects of land management types in woodlands

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Forest Ecosystems 2021年第4期8卷 991-1005页

作者： Carolina R.Szymanski Solana Tabeni Juan A.alvarez Claudia M.Campos Instituto Argentino de Nivologia Glaciologia y Ciencias AmbientalesCCT CONICET MendozaAv.Ruiz Leal s/nParque General San Martin5000 MendozaArgentina Facultad de Ciencias Agrarias Universidad Nacional de CuyoAlte.Brown s/nChacras de Coria5505 MendozaArgentina Instituto Argentino de Investigaciones de las Zona Aridas(UNCuyo-Gobierno de Mendoza-CONICET) CCT CONICET MendozaAv.Ruiz Leal s/nParque General San Martin5000 MendozaArgentina

Background:The ecological indicators are useful tools to determine the effects of human disturbances on woodland ***,ecological indicators not always responded in the same way to disturbances,and the responses can differ among *** arid and semiarid woodlands,the use of deadwood associated with cattle raising can affect biodiversity and Nature’s contributions to ***:Our study aimed to assess changes in taxonomic and functional diversity of two assemblages,plants and mammals,in Prosopis woodlands under different land management types:grazed woodlands and a protected *** plants,changes in structural diversity were also *** trees under different land management types were selected and their deadwood characteristics were *** live traps and camera traps,we obtained data on the presence-absence of mammals per tree to estimate diversity *** plants,we measured the abundance of vegetation by species and by cover type through the Line-Intercept Method to estimated ***,we built generalized linear models to assess the responses of diversity of each assemblage to covariables concerning deadwood and different land management ***:We found that all diversity indeces for plants were either negatively affected by the presence of deadwood on the ground,or favored by its *** mammals,removal of deadwood increased taxonomic diversity,while functional diversity increased with deadwood on the *** structural diversity of plants and functional diversity of mammals were greater in grazed ***:The sustainable use of woodland resources is essential for the activities of rural *** study results indicated that land management of grazed woodlands promoted the structural diversity of plant assemblages and the functional diversity of *** presence of deadwood negatively affected plant diversity but it increased mammal functional *** is a

关键词： Central Monte Cattle raising Deadwood extraction Taxonomic diversity Functional traits

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非常规油气开发中润湿性反转技术的应用

石油勘探与开发 2016年第5期43卷 764-771页

作者： alvarez J O SCHECHTER D S Texas A & M University

研究了适用于非常规油气储集层的岩石润湿性测量方法,总结了非常规油气储集层岩石润湿性特征,分析了非常规油气储集层岩石润湿性反转技术的应用情况,并介绍了研究表面活性剂与非常规油气储集层岩石润湿性间关系的实验方法。研究表明:接... 详细信息

研究了适用于非常规油气储集层的岩石润湿性测量方法,总结了非常规油气储集层岩石润湿性特征,分析了非常规油气储集层岩石润湿性反转技术的应用情况,并介绍了研究表面活性剂与非常规油气储集层岩石润湿性间关系的实验方法。研究表明:接触角法、核磁共振法和Zeta电位测量法是评估非常规油气储集层岩石润湿性最恰当的方法,非常规油气储集层呈现出中性润湿到油湿的混合润湿特性。润湿性反转技术在非常规油气储集层中的应用目前仅限于添加表面活性剂。在压裂液中加入表面活性剂可改变非常规油气储集层岩石润湿性从而提高原油采收率。借助稳定性实验、润湿性反转评估实验、界面张力实验、自吸实验、压吸实验和吸附实验等可评估表面活性剂改变润湿性及提高采收率的效率。

关键词：非常规油气储集层润湿性润湿性反转表面活性剂自吸提高原油采收率页岩油

Triboelectric nanogenerator based on electrodeposited Ag octahedral nano-assemblies

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能源化学:英文版 2023年第8期83卷 478-495,I0012页

作者： M.Edith Navarro-Segura Margarita Sanchez-Dominguez Ana Arizmendi-Morquecho J.alvarez-Quintana Group of Colloidal and Interfacial Chemistry Applied to Nanomaterials and Nanoformulations Centro de Investigacion en Materiales Avanzados S.C Unidad MonterreyAlianza Norte#202Autopista Monterrey-Aeropuerto Km.10.C.P.66628 ApodacaNuevo LeonMexico GENES-Group of Embedded Nanomaterials for Energy Scavenging Centro de Investigacion en Materiales Avanzados S.C.Unidad MonterreyAlianza Norte#202Autopista Monterrey-Aeropuerto Km.10.C.P.66628 ApodacaNuevo LeonMexico

The tremendous potential of triboelectric generators-TENGs for converting mechanical energy into electrical energy places them as one of the most promising energy harvesting technologies. In this work, the fabrication of enhanced performance TENGs using Ag octahedron nano-assemblies on ITO as electrodes significantly increases the electric charge collection of the induced tribocharges. Thereby, nanostructured electrical contacts coated with Ag macroscale nano-assemblies with octahedral features were obtained by the electrodeposition technique on flexible PET/ITO substrates. Consequently, the nanostructured triboelectric generator-TENG exhibited 65 times more maximum output power, and almost 10 times more open circuit output voltage than that of a TENG with non-nanostructured contacts passing from μW to m W capabilities, which was attributed to the increment of intrinsic interface states due to a higher effective contact area in the former. Likewise, output performances of TENGs also displayed an asymptotic behavior on the output voltage as the operating frequency of the mechanical oscillations increased, which is attributed to a decrement in the internal impedance of the device with frequency. Furthermore, it is shown that the resulting electrical output power can successfully drive low power consumption electronic devices. On that account, the present research establishes a promising platform which contributes in an original way to the development of the TENGs technology.

关键词： Triboelectric generator Nanostructured electrodeposited electrodes Ag octahedral nanoassemblies Electrode surface structure

Assessment of Mg(OH)_(2)/TiO_(2) coating in the Mg-Ca-Zn alloy for improved corrosion resistance and antibacterial performance

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Journal of Magnesium and Alloys 2023年第1期11卷 361-378页

作者： Leonardo Hernández Jesús Ramón-Sierra montserrat Soria-Castro Ángel Bacelis Geonel Rodríguez-Gattorno Elizabeth Ortiz-Vázquez Gloria Acosta Applied Physics Department Center for Research and Advanced Studies of the National Polytechnic Institute(CINVESTAV-IPN)Carr.Ant.a Progreso km.6C.P.97310MeridaYucatanMexico Tecnológico Nacional de México/Instituto Tecnológico de Mérida.Av.Tecnológico s/n Km.4.5 ant.Carr.Mérida-Progreso C.P.97118MéridaYucatánMéxico Facultad de Química Universidad Nacional Autónoma de México(UNAM)Av.Universidad 3000C.P.04510CoyoacánCDMXMéxico

The high activity of metallic magnesium and alloys limits its potential in biomedical applications;in recent years,extensive efforts have been devoted to modulating this *** this work,we present Mg(OH)_(2) and TiO_(2)barrier coatings to reduce the degradation of magnesium alloy(Mg-Ca-Zn)*** coatings were deposited by the anodization method and the spin-coating technique,*** anodized layer was coated with TiO_(2)generated from the hydrolysis of 3%weight of TTIP(Ti[OCH(CH_(3))_(2)]_(4),Titanium(IV)isopropoxide)in 2-Propanol deposited by the spin-coating *** the degradation in Ringer’s solution by electrochemical impedance spectroscopy and OCP revealed a 98%reduction in pittings in uncoated samples after 14 days of *** p H measurements revealed that the TiO_(2)coating reduced the alkalization of the physiological environment,keeping the pH at 6.0 *** vitro studies of two types of bacteria(*** and ***)exhibited zones of inhibition in the agar and activity bactericidal(kill time test).The mechanisms behind the improved degradation resistance and enhanced antibacterial activity are presented and discussed *** modification with Mg(OH)_(2)/TiO_(2)coatings is a promising strategy to control the biodegradation of magnesium implants for bone regeneration.

关键词： Magnesium alloy EIS Mg(OH)_(2) TiO_(2) Antibacterial coatings

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.

Stable and efficient metal-biochar supported catalyst:degradation of model pollutants through sulfate radical-based advanced oxidation processes

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Biochar 2020年第3期2卷 319-328页

作者： Fermín Delgado Victoria S.Gutierrez Mariana Dennehy Mariana alvarez INQUISUR Departamento de QuímicaUniversidad Nacional del SurAv.Alem 12538000 Bahía BlancaArgentina Planta Piloto de Ingeniería Química PLAPIQUI(CONICET-UNS)Camino La Carrindanga Km 78000 Bahía BlancaArgentina

This study focuses on the synthesis of metal-based biochar catalysts and their catalytic activation of peroxymonosulfate(PMS,HSO5−)for the degradation of three different wastewater model pollutants employing advanced oxidation processes(AOP).Iron,copper,and two different cobalt-based catalysts were prepared and *** catalysts were supported on a biochar obtained from the pyrolysis of woody pruning *** were characterized by C,H,and N elemental analysis,X-Ray diffraction(XRD),Fourier-transform infrared spectroscopy(FTIR),and scanning electron microscope(SEM).The metal content in each catalyst was determined by means of atomic absorption spectroscopy(AAS).The degradation reac-tions of benzoic acid(BA),catechol(C),and cinnamic acid(CA)were carried out in a lab scale batch glass reactor and were followed by UV-Visible spectroscopy(UV-Vis).A colorimetric technique was employed to verify the presence of oxidant during the reaction *** catalyst/oxidant optimal ratio was determined for the cobalt *** mineralization degree of the pollutants after the degradations was verified by means of total organic carbon(TOC)content in the residual *** 4 h of reaction,the maximum mineralization was reached when C was treated with a cobalt-based catalyst(>80%),and its stability was evaluated through successive cycles of use.

关键词： Biochar Organic pollutants Advanced oxidation processes Sulfate radicals Cobalt catalysts

Development of heartwood,sapwood,bark,pith and specific gravity of teak(Tectona grandis)in fast-growing plantations in Costa Rica

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Journal of Forestry Research 2020年第2期31卷 667-676页

作者： Alexander Berrocal Johana Gaitan-alvarez Roger Moya David Fernandez-Solis Edgar Ortiz-Malavassi Instituto Tecnologico de Costa Rica Escuela de Ingenieria ForestalCartago Apartado 159-7050Costa Rica

To elucidate the development of heartwood,bark,sapwood,pith and specific gravity of wood in fastgrowing teak(Tectona grandis)plantations in Costa Rica,we sampled three trees in each of 55 plantations and modelled each variable with age,site and different tree *** and stand density of plantations were significant correlated with stem diameter at breast height and total height of the *** of heartwood was initiated at the age of 4-year-old and increased in direct proportion with *** age of plantation had a significant relationship with stem diameter at breast height,heartwood percentage,sapwood thickness,sapwood percentage,percentage of bark,pith diameter and percentage,and specify *** model for these tree parameters was model with these parameters as dependent variable and in relation to age as independent variable.

关键词： Teak Growth Tree morphology parameters Morphology Tree development

Are the changes in the peripheral brain-derived neurotrophic factor levels due to platelet activation?

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World Journal of Psychiatry 2016年第1期6卷 84-101页

作者： montserrat Serra-Millàs Osona Mental Health Hospital Universitari de VicSalut Mental i Innovació Social (SaMIS)Universitat de Vic-Universitat Central de Catalunya

Brain-derived neurotrophic factor(BDNF) plays an important role in central nervous system development, neurogenesis and neuronal plasticity. BDNF is also expressed in several non-neuronal tissues, and it could play an important role in other processes, such as cancer, angiogenesis, etc. Platelets are the major source of peripheral BDNF. However, platelets also contain high amounts of serotonin; they express specific surface receptors during activation, and a multitude of pro-inflammatory and immunomodulatory bioactive compounds are secreted from the granules. Until recently, there was insufficient knowledge regarding the relationship between BDNF and platelets. Recent studies showed that BDNF is present in two distinct pools in platelets, in α-granules and in the cytoplasm, and only the BDNF in the granules is secreted following stimulation, representing 30% of the total BDNF in platelets. BDNF has an important role in the pathophysiology of depression. Low levels of serum BDNF have been described in patients with major depressive disorder, and BDNF levels increased with chronic antidepressant treatment. Interestingly, there is an association between depression and platelet function. This review analyzed studies that evaluated the relationship between BDNF and platelet activation and the effect of treatments on both parameters. Only a few studies consider this possible confounding factor, and it could be very important in diseases such as depression, which show changes in both parameters.

关键词： Platelets Brain derived neurotrophic factor Depression Antidepressants Biomarkers