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Extreme drought triggers parallel shifts in wood anatomical and physiological traits in upper treeline of the Mediterranean Andes

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Ecological Processes 2024年第01期13卷 132-143页

作者： Luiz Santini Jr. Dylan Craven Daigard Ricardo Ortega Rodriguez Manolo Trindade Quintilhan Stephanie Gibson-Carpintero Cristina Aravena torres Fidel A.Roig Ariel A.Mu?oz Alejandro Venegas-gonzalez Hémera Centro de Observación de la Tierra Universidad Mayor GEMA Center for Genomics Ecology and Environment Universidad Mayor Data Observatory Foundation ANID Technology Center Depart-ment of Forest Sciences ESALQ-University of Sao Paulo Department of Plant Biology Institute of Biology University of Campinas Instituto de Geografía Universidad Nacional Autónoma de México (UNAM) Argentine Institute of Nivology Glaciology and Environmental Sciences(IANIGLA CONICET ) Institute of Geography Pontificia Universidad Católica de Valparaíso Instituto de Ciencias Agroalimentarias Animales y Ambientales (ICA3) Universidad de O'Higgins

Background Treeline ecotones of Mediterranean ecoregions have been affected by the increasing intensity and severity of droughts. Even though the effect of droughts on forest dynamics has been widely documented, knowledge is relatively scarce of how extreme climate episodes affect the hydraulic structure and, therefore, the phys-iology of woody plants. The Mediterranean Andes have experienced an uninterrupted period of drought since 2010, including an extremely dry year in 2019 with approximately 80% rainfall deficit. Here, we investigated shifts in wood anatomical and physiological traits of Kageneckia angustifolia, an endemic treeline species, in response to this drought *** We evaluated the xylem plasticity of three K. angustifolia populations across their natural distribution(31–35° SL) based on anatomical(vessel structure and distribution) and physiological(intrinsic water-use efficiency) variables in the tree rings. We focused on the period 2000–2020 that corresponds to before the megadrought(2000–2007),(ii) megadrought(2008–2018) and(iii) hyperdrought(2019–2020). The variables were annualized and analyzed by linear mixed-effects *** Our results provide insights to the anatomical and physiological mechanisms underlying the resilience of treeline forests to persistent droughts in central Chile. We found that the extreme drought in 2019–2020 triggered shifts in vessel size and frequency that increased hydraulic safety. These significant shifts in vessel traits occurred in parallel with a decrease in pit aperture area and an increase in water-use efficiency, further increasing the resilience of K. angustifolia to extreme drought *** Our results revealed coordinated shifts in vessel size and frequency and water-use efficiency in response to the megadrought, thereby reducing vulnerability to hydraulic failure. The apparent resilience of K. angustifolia to extreme droughts suggests that this adaptation to drought stress may incre

关键词： Dendro-anatomy Kageneckia angustifolia Xylem vulnerability Drought Climate change

A Novel and Functional Artificial Bruch’s Membrane Made of Poly (ε-Caprolactone)/Gelatin for Retinal Pigment Epithelium Restoration

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Advances in Bioscience and Biotechnology 2024年第8期15卷 443-461页

作者： López Edith Silva-Bermudez Phaedra gonzalez-Salinas Roberto Velasquillo Cristina torres-Romero Abigail López-Colomé Ana María Pérez Armando Gina Prado-Prone Edgar Ramos-Martínez Iván Ramos-Martínez Quiroz-Mercado Hugo Hernández-Zimbrón Luis Fernando Instituto de Fisiologa Celular Universidad Nacional Autnoma de Mxico Ciudad de Mxico City Mxico Unidad de Ingeniería de Tejidos Terapia Celular y Medicina Regenerativa Instituto Nacional de Rehabilitación Luis Guiller-mo Ibarra Ibarra Ciudad de México México Departamento de Investigacin Asociacin Para Evitar la Ceguera Ciudad de Mxico Mxico Subdireccin de Investigacin Tecnolgica Instituto Nacional de Rehabilitacin Luis Guillermo Ibarra Ibarra Ciudad de Mxico Mxico Departamento de Biologa Celular y Tisular Facultad de Medicina Universidad Nacional Autnoma de Mxico Ciudad de Mxico Mxico Escuela de Ciencias Universidad Autnoma Benito Jurez de Oaxaca Oaxaca Mxico Departamento de Medicina y Zootecnia de Cerdos Facultad de Medicina Veterinaria y Zootecnia Universidad Nacional utnoma de Mxico Mxico Laboratorio de Investigacion Interdisciplinaria rea de Optometria Escuela Nacional de Estudios Superiores Unidad Len Universidad Nacional Autnoma de Mxico Len Guanajuato Mxico Laboratorio Nacional de ptica de la Visin-Centro de Investigaciones en ptica Len Guanajuato Mxico

Purpose: The primary aim of this paper is to design, create, and improve functional and artificial Bruch’s membranes (BM) using bioengineering techniques, which can be applied in the treatment of maculopathies by supporting the growth and maintenance of retinal pigment epithelium (RPE) cells, thereby potentially enabling subretinal implantation in patients. Methods: We fabricated by electrospinning ultrathin 3D nanofibrous membranes from Polycaprolactone (PCL), and different concentrations of gelatin (5%, 15% and 30%). ARPE-19 cells were seeded onto these artificial membranes. MTT assays were performed in order to evaluate ARPE-19 cell viability and cytotoxicity. IF assays were realized to observe the ARPE-19 cells onto each membrane. Ultrastructure of the modified Bruch’s membrane and ARPE-19 morphology after 25 days of culture were studied with transmission and scanning electron microscopy. To evaluate expression changes in markers of ARPE-19 (RPE65 and ZO-1) qRT-PCR assays were realized. Data from three independent experiments were pooled and expressed as the mean SD. A confidence level of P 0.05 was considered to be statistically significant. Results ARPE-19 cells grew on PCL/Gelatin membranes mainly in PCL/30% gelatin combination, which had not cytotoxic effect. RPE65/cytokeratin-18/ and actin-positive ARPE-19 cells formed a correctly orientated monolayer of polygonal cells with morphological polarity. The apical cell surfaces exhibited abundant protruding microfolds. Moreover, zones of polygonal border look as if ARPE-19 cells fused among, suggesting the presence of tight junctions. The expression of RPE65 and ZO-1 was unchanged. Conclusions: PCL/30% Gelatine membranes may imitate the natural BM to such extent that they support RPE-cells and exhibited RPE-like morphology. The engineering of a human RPE monolayer with these artificial BM, emulating the in vivo retina, arouse their potential subretinal implantation in patients with wet age-related macular degene

关键词： Artificial Bruch’s Membrane Electrospinning ARPE-19 Cells Age-Related Macular Degeneration

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

Hepatitis C virus clearance and less liver damage in patients with high cholesterol, low-density lipoprotein cholesterol and APOE ε4 allele

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World Journal of Gastroenterology 2019年第38期25卷 5826-5837页

作者： Karina gonzalez-Aldaco Sonia Roman Rafael torres-Valadez Claudia Ojeda-Granados Luis A torres-Reyes Arturo Panduro Department of Molecular Biology in Medicine Civil Hospital of Guadalajara "Fray Antonio Alcalde" and Health Sciences Center University of Guadalajara

BACKGROUND Cholesterol is related to improvements in the rate of sustained virological response and a robust immune response against the hepatitis C virus(HCV).APOE gene polymorphisms regulate cholesterol levels modifying the course of the HCV *** relationship between cholesterol,APOE alleles,and the outcome of HCV infection has not been evaluated in the admixed population of *** To investigate the role of APOE-ε2,-ε3,and-ε4 alleles and the metabolic profile in the outcome of HCV *** A total of 299 treatment-na?ve HCV patients were included in this retrospective *** were stratified in chronic hepatitis C(CHC)(n=206)and spontaneous clearance(SC)(n=93).A clinical record was *** tests were assessed by dry chemistry *** genotypes were determined using a Real-Time polymerase chain reaction *** Total cholesterol,low-density lipoprotein cholesterol(LDL-c),triglycerides,and hypercholesterolemia were higher in SC than CHC patients as well as the frequency of the APOEε4 allele(12.4%vs 7.3%).SC patients were overweight(54.8%).Theε4 allele was associated with SC(OR=0.55,95%CI:0.31-0.98,P=0.042)and mild fibrosis(F1-F2)in CHC patients(OR 0.091,95%CI 0.01-0.75,P=0.020).LDL-c≥101.5 mg/dL(OR=0.20,95%CI:0.10-0.41,P<0.001)and BMI≥26.6 kg/m2(OR=0.37,95%CI:0.18-0.76,P<0.001)were associated with SC status;while ALT≥50.5 IU/L was negatively associated(OR=5.67,95%CI:2.69-11.97,P<0.001).CONCLUSION In SC patients,the APOEε4 allele and LDL-c conferred a protective effect in the course of the HCV infection in the context of excess body weight.

关键词： Liver damage Body mass index Spontaneous hepatitis C virus clearance Low-density lipoprotein Cholesterol

In vitro antioxidant,antilipoxygenase and antimicrobial activities of extracts from seven climbing plants belonging to the Bignoniaceae

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Journal of Integrative Medicine 2018年第4期16卷 255-262页

作者： Carola Analla torres Cristina Marisel Perez Zamora Maria Beatriz Nunez Ana Maria gonzalez Laboratory of Microbiology and Pharmaceutical Technology Department of Basic and Applied SciencesNational University of Chaco AustralPresidencia Roque Saenz Pena 3700ChacoArgentina National Council for Scientific and Technical Research(CONICET) Godoy Cruz 2290Buenos Aires C1425FQBArgentina Institute of Botany of the Northeast(IBONE-CONICET) Sargento Juan Bautista Cabral 2131CorrientesArgentina

Objectives： This study aimed to evaluate the in vitro antioxidant capacity, to determine the anti-inflammatory effect due to lipoxygenase inhibition and to test the antimicrobial activity of ethanolic extracts from leaves of seven climbing species belonging to the Bignoniaceae family. These species are Adenocalyrnrna rnarginatum （Cham.） DC., Amphilophium vauthieri DC., Cuspidaria convoluta （VEIL） A. H. Gentry, Dolichandra dentata （K. Schum.） L. G. Lohmann, Fridericia caudigera （S. Moore） L. G. Lohmann, Fridericia chica （Bonpl.） L. G. Lohmann and Tanaecium selloi （Spreng.） L. G. Lohmann. Methods： The antioxidant activity was evaluated using three methods, 2,2＇-azino-bis（3-ethylbenzothiazo line-6-sulfonic acid）（ABTS）, 2,2-diphenyl-l-picrylhydrazyl （DPPH）, and ferric reducing antioxidant power. Lipoxygenase-inhibiting activity was assayed spectrophotometrically; the result was expressed as percent inhibition. The antimicrobial activity was assessed using the agar disk diffusion method. Minimal inhibitory concentration （MIC） and minimal bactericidal]fungicidal concentration were also determined for each extract against 12 pathogenic bacterial strains of Staphylococcus aureus and seven fungal strains of the Candida genus. The identification of the major compounds present in the most promising extract was established by high-performance liquid chromatography-tandem mass spectrometry. Results： C convoluta, F. caudigera, and F. chica exhibited the best antioxidant activity by scavenging DPPH and ABTS~ radicals and reducing Fe3＋ ion. These extracts showed a notable inhibition of lipnxygenase. F. caudigera was found to have the lower MIC value against S. aureus strains and six Candida species. The extracts of F. caudigera and C. convoluta were active even against methicillin-resistant S. aureus. C convoluta had higher total phenol content, better antioxidant activity and superior anti- inflammatory and antimicrobial activity. The main phenolic compounds found in this extract

关键词： Cuspidaria Fridericia Antioxidants Lipoxygenase Antimicrobials Herbal drugs Free radical scavengers

Influence of COM-peptides/proteins on the properties of flocs formed at different shear rates

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Journal of Environmental Sciences 2019年第6期31卷 116-127页

作者： Monika Filipenska Petra Vasatova Lenka Pivokonska Lenka Cermakova andrea gonzalez-torres Rita K.Henderson Jana Naceradska Martin Pivokonsky Institute of Hydrodynamics of the Czech Academy of Sciences Institute for Environmental Studies Faculty of Science Charles University The bioMASS Lab School of Chemical Engineering The University of New South Wales

Coagulation followed by floc separation is a key process for the removal of algal organic matter(AOM) in water treatment. Besides optimizing coagulation parameters,knowledge of the properties of AOM-flocs is essential to maximizing AOM ***, the impact of AOM on the floc properties remains unclear. This study investigated how peptides/proteins derived from the cellular organic matter(COM) of the cyanobacterium Microcystis aeruginosa influenced the size, structure, and shape of flocs formed at different shear rates(G). Flocs formed by kaolinite, COM-peptides/proteins and a mixture of the same were studied, and the effect of intermolecular interactions between floc components on floc properties was assessed. The coagulation experiments were performed in a Taylor–Couette reactor, with aluminum(Al) or ferric sulphate(Fe) utilized as coagulants. Image analysis was performed to gauge floc size and obtain data on fractal dimension. It was found that floc properties were affected by the presence of the COM-peptides/proteins and the coagulant used. COM-peptides/proteins increased floc size and porosity and widened floc size distributions. The Fe coagulant produced larger and less compact flocs than Al coagulant. Moreover, the decrease in floc size that occurred in parallel with increase in shear rate was not smooth in progress. A rapid change for the kaolinite-coagulant suspension and two rapid changes for the suspensions containing COM were observed. These were attributed to various intermolecular interactions between floc components participating in coagulation at different G. Based on the results obtained, shear rates suitable for efficient separation of flocs containing COM were suggested.

关键词： Algal organic matter Floc size Coagulation Image analysis Water treatment

Small-signal Model for Dual-active-bridge Converter Considering Total Elimination of Reactive Current

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Journal of Modern Power Systems and Clean Energy 2021年第2期9卷 450-458页

作者： Juan Ramon Rodriguez-Rodriguez Nadia Maria Salgado-Herrera Jacinto torres-Jimenez Nestor gonzalez-Cabrera David Granados-Lieberman Martin Valtierra-Rodriguez the Universidad Nacional Autonoma de Mexico Facultad de IngenieriaDepto.Energia Electri-ca.Av.Universidad 3000Col.UNAM CUCoyoacanCDMXMexico the Instituto de Energias Renovables Universidad Nacional Autonoma de MexicoPriv.Xochicalco s/nCol.Centro.TemixcoMorelosMexico the Instituto Tec-nologico Superior de Irapuato Carretera Irapuato-Silao km 12.5.IrapuatoGuanajuatoMexico the Universidad Autonoma de Queretaro Campus San Juan del RioRio Moctezuma 249San Juan del RioQueretaroMexico

Emerging technologies such as electric vehicles,solid-state transformers,and DC transformers are implemented using the closed-loop bi-directional dual-active-bridge(DAB)*** this context,it is necessary to have average models that provide an efficient way of tuning the proportional integral(PI)compensator parameters for large-and small-signal *** present a novel small-signal model(SSM)for DAB converter with a single closed-loop PI controller and the total elimination of reactive current(IQ=0).The method applies a modulation technique for IQ=0 and introduces a composite function in the controller while reducing the original nonlinear switching model,which allows to decrease the order of the transfer function and analyze the closed-loop *** proposed SSM is analyzed using different response time,load,and DC voltage *** simulation and experimental results demonstrate the ease of implementation and effectiveness of the proposed model with respect to other SSM techniques.

关键词： Small-signal model(SSM) dual-active-bridge(DAB)converter reactive current elimination proportional integral(PI)control

Human CD4 ＋ effector T lymphocytes generated upon TCR engagement with self-peptides respond defectively to IL-7 in their transition to memory cells

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Cellular & Molecular Immunology 2013年第3期10卷 261-274页

作者： Gabriela gonzalez-Perez Norma C Segovia Amaranta Rivas-Carvalho Diana P Reyes Honorio torres-Aguilar Sergio R Aguilar-Ruiz Claudine Irles Gloria Soldevila Carmen Sainchez-torres 1Department of Molecular Biomedicine Centre de Investigacion y de Estudios Avanzados del I.P.N. (CINVESTAV-IPN) Mexico City Mexico Department of Physiology Facultad de Medicina Mexico City Mexico Department of Immunology Institute de Investigaciones Biomedicas Universidad Nacional Autonoma de Mexico (UNAM) Mexico City Mexico

The peripheral repertoire of CD4＋ T lymphocytes contains autoreactive cells that remain tolerant through several mechanisms. However, nonspecific CD4＋ T cells can be activated in physiological conditions as in the course of an ongoing immune response, and their outcome is not yet fully understood. Here, we investigate the fate of human naive CD4＋ lymphocytes activated by dendritic cells （DCs） presenting endogenous self-peptides in comparison with lymphocytes involved in alloresponses. We generated memory cells （Tmem） from primary effectors activated with mature autologous DCs plus interleukin （IL）-2 （Tmauto）, simulating the circumstances of an active immune response, or allogeneic DCs （Tmallo）. Tmem were generated from effector cells that were rested in the absence of antigenic stimuli, with or without IL-7. Tmem were less activated than effectors （demonstrated by CD25 downregulation） particularly with IL-7, suggesting that this cytokine may favour the transition to quiescence. Tmauto and TmaHo showed an effector memory phenotype, and responded similarly to polyclonal and antigen-specific stimuli. Biochemically, IL-7-treated Tma^o were closely related to conventional memory lymphocytes based on Erk-l/2 activation, whereas Tmauto were more similar to effectors. Autologous effectors exhibited lower responses to IL-7 than allogeneic cells, which were reflected in their reduced proliferation and higher cell death. This was not related to IL-7 receptor expression but rather to signalling deficiencies, according to STAT5 activation These results suggest that ineffective responses to IL-7 could impair the transition to memory cells of naive CD4＋ T lymphocytes recognizing self-peptides in the setting of strong costimulation.

关键词： human CD4+ T cells IL-7 memory self-peptides

Immunologic, metabolic and genetic factors in hepatitis C virus infection

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World Journal of Gastroenterology 2014年第13期20卷 3443-3456页

作者： Nora A Fierro Karina gonzalez-Aldaco Rafael torres-Valadez Erika Martinez-Lopez Sonia Roman Arturo Panduro Department of Molecular Biology in Medicine Civil Hospital of Guadalajara"Fray Antonio Alcalde" and Health Sciences CenterUniversity of GuadalajaraGuadalajara 44280JaliscoMexico

The mechanisms that regulate disease progression during hepatitis C virus(HCV)infection and the response to treatment are not clearly *** studies have demonstrated that a strong host immune response against HCV favors HCV *** addition,genetic factors and metabolic machinery,particularly cholesterol modulation,are involved in HCV *** is likely that the interplay between all of these factors contributes to the outcome of HCV *** recent years,the world has experienced its largest epidemic of *** and the United States are the leading sufferers from this epidemic at the global *** is associated with the development ofnumerous pathologies including hypercholesterolemia which is one of the eight most important risk factors for mortality in *** may be related to the course of HCV infection in this ***,we focus on the urgent need to study the progression of HCV infection in relation to ethnic *** are discussed that hold promise in identifying immune,metabolic and genetic factors that,in conjunction,could be therapeutic targets or predictors of the progression of HCV infection.

关键词： Hepatitis C virus Immune response Lipids Metabolism Genetics