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MXene multi-functionalization of polyrotaxane based PCMs and the applications in electronic devices thermal management 被引量:1
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作者 Guangzhong Yin Alba Marta Lopez +5 位作者 Ignacio Collado Antonio Vazquez-Lopez Xiang Ao Jose Hobson Silvia G.Prolongo Deyi Wang 《Nano Materials Science》 EI CAS CSCD 2024年第5期495-503,共9页
The aim of this work was to improve the thermal conductivity and electromagnetic shielding of the leakage proof phase change materials(PCMs),in which a polyrotaxane(PLR)was used as a support material to encapsulate PE... The aim of this work was to improve the thermal conductivity and electromagnetic shielding of the leakage proof phase change materials(PCMs),in which a polyrotaxane(PLR)was used as a support material to encapsulate PEG 1k or PEG 6k and MXene as multi-functional filler.The PCMs can be processed conveniently by a hot press and the PEG 1k containing samples showed excellent flexibility.We conducted a systematic evaluation of the phase transition behavior of the material,thermal conductivity and electromagnetic shielding performance tests.Notably,the PCMs achieved a high enthalpy values(123.9–159.6 J/g).The PCMs exhibited an increase of 44.3%,and 137.5%in thermal conductivity values with higher MXene content(5 wt%)for PLR-PEG6k and PLR-PEG1k,respectively,and show high shape stability and no leakage during and after phase transition.The introduction of MXene can significantly improve the electromagnetic shielding performance of PCM composites.Typically,higher conductive samples(samples which contain high MXene contents)offer a higher EMI SE shielding,reaching a maximum of 4.67 dB at 5.6 GHz for PLR-1K-MX5.These improvements solve the main problems of organic PEG based PCMs,thus making PLR-PEG-MXene based PCMs good candidates for thermoregulators of both solid-state disks and smart phone.It is worth pointing out that the sample PLR-1k-MX5 can decrease 4.3C of the reference temperature during cellphone running.Moreover,the temperature of the protecting sheet in the simulated solid state disk with PCM was significantly lower(showing a decreasing of 7.9℃)compared with the blank sample. 展开更多
关键词 Phase change materials Thermal regulation MXene POLYROTAXANE NANOCOMPOSITES
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Genetically-and environmentally-dependent processes drive interspecific and intraspecific divergence in the Chinese relict endemic genus Dipteronia
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作者 Tao Zhou Xiaodan Chen +6 位作者 Jordi López-Pujol Guoqing Bai Sonia Herrando-Moraira Neus Nualart Xiao Zhang Yuemei Zhao Guifang Zhao 《Plant Diversity》 SCIE CAS CSCD 2024年第5期585-599,共15页
China is a hotspot of relict plant species that were once widespread throughout the Northern Hemisphere.Recent research has demonstrated that the occurrence of long-term stable refugia in the mountainous regions of ce... China is a hotspot of relict plant species that were once widespread throughout the Northern Hemisphere.Recent research has demonstrated that the occurrence of long-term stable refugia in the mountainous regions of central and south-western China allowed their persistence through the late Neogene climate fluctuations.One of these relict lineages is Dipteronia,an oligotypic tree genus with a fossil record extending to the Paleocene.Here,we investigated the genetic variability,demographic dynamics and diversification patterns of the two currently recognized Dipteronia species(Dipteronia sinensis and D.dyeriana).Molecular data were obtained from 45 populations of Dipteronia by genotyping three cpDNA regions,two single copy nuclear genes and 15 simple sequence repeat loci.The genetic study was combined with niche comparison analyses on the environmental space,ecological niche modeling,and landscape connectivity analysis.We found that the two Dipteronia species have highly diverged both in genetic and ecological terms.Despite the incipient speciation processes that can be observed in D.sinensis,the occurrence of long-term stable refugia and,particularly,a dispersal corridor along Daba Shan-west Qinling,likely ensured its genetic and ecological integrity to date.Our study will not only help us to understand how populations of Dipteronia species responded to the tectonic and climatic changes of the Cenozoic,but also provide insight into how Arcto-Tertiary relict plants in East Asia survived,evolved,and diversified. 展开更多
关键词 Dipteronia Interspecific/intraspecific divergence Genetic structure Climatic niche divergence Dispersal corridor
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Cytokine release syndrome induced by anti-programmed death-1 treatment in a psoriasis patient:A dark side of immune checkpoint inhibitors
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作者 JoséLuis Maldonado-García Ana Fragozo Lenin Pavón 《World Journal of Clinical Cases》 SCIE 2024年第35期6782-6790,共9页
In recent years,cancer immunotherapy has introduced novel treatments,such as monoclonal antibodies,which have facilitated targeted therapies against tumor cells.Programmed death-1(PD-1)is an immune checkpoint expresse... In recent years,cancer immunotherapy has introduced novel treatments,such as monoclonal antibodies,which have facilitated targeted therapies against tumor cells.Programmed death-1(PD-1)is an immune checkpoint expressed in T cells that regulates the immune system’s activity to prevent over-activation and tissue damage caused by inflammation.However,PD-1 is also expressed in tumor cells and functions as an immune evasion mechanism,making it a therapeutic target to enhance the immune response and eliminate tumor cells.Consequently,immune checkpoint inhibitors(ICIs)have emerged as an option for certain tumor types.Nevertheless,blocking immune checkpoints can lead to immune-related adverse events(irAEs),such as psoriasis and cytokine release syndrome(CRS),as exemp-lified in the clinical case presented by Zhou et al involving a patient with adva-nced gastric cancer who received sintilimab,a monoclonal antibody targeting PD-1.Subsequently,the patient experienced exacerbation of psoriasis and CRS.The objective of this editorial article is to elucidate potential immunologic mechanisms that may contribute to the development of CRS and psoriasis in patients receiving ICIs.It is crucial to acknowledge that while ICIs offer superior safety and efficacy compared to conventional therapies,they can also manifest irAEs affecting the skin,gastrointestinal tract,or respiratory system.In severe cases,these irAEs can lead to life-threatening complications such as circulatory shock or multiorgan failure.Consequently,it is recommended that patients receiving ICIs undergo regular monitoring to identify and manage these adverse events effectively. 展开更多
关键词 Immune checkpoints inhibitors Programmed death-1 Cancer immunotherapy PSORIASIS Cytokine release syndrome Immune-related adverse events
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A Novel and Functional Artificial Bruch’s Membrane Made of Poly (ε-Caprolactone)/Gelatin for Retinal Pigment Epithelium Restoration
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作者 López Edith Silva-Bermudez Phaedra +9 位作者 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 《Advances in Bioscience and Biotechnology》 CAS 2024年第8期443-461,共19页
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 sup... 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 degeneration (AMD) where there is a rupture of the Bruch’s membrane. 展开更多
关键词 Artificial Bruch’s Membrane ELECTROSPINNING ARPE-19 Cells Age-Related Macular Degeneration
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An unprotected vulnerable relict subtropical conifer-Keteleeria evelyniana: Its forests, populations, growth and endangerment by invasive alien plant species in China
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作者 Cindy Q.Tang Min-Rui Du +10 位作者 Huan-Chong Wang You-Cai Shi Jia-Le Zeng Shu-Li Xiao Peng-Bin Han Jian-Ran Wen Shi-Qian Yao Ming-Chun Peng Chong-Yun Wang Yong-Ping Li Jordi López-Pujol 《Plant Diversity》 SCIE CAS CSCD 2024年第5期648-660,共13页
Relict subtropical coniferous forests in China face severe fragmentation,resulting in declining populations,and some are under significant threat from invasive alien species.Despite the crucial importance of understan... Relict subtropical coniferous forests in China face severe fragmentation,resulting in declining populations,and some are under significant threat from invasive alien species.Despite the crucial importance of understanding forest dynamics,knowledge gaps persist,particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria evelyniana.In this study,we investigated the impact of invasive plants on the regeneration of forests dominated by K.evelyniana,a subtropical relict species in southwestern China.For this purpose,we characterized forest dynamics of 160 forest plots featuring K.evelyniana as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of K.evelyniana.We identified four distinct forest types in which K.evelyniana was dominant.We found that radial growth of K.evelyniana trees is faster in younger ageclasses today than it was for older trees at the same age.The population structure of K.evelyniana in each forest type exhibited a multimodal age-class distribution.However,three forest types lacked established saplings younger than 10 years old,a situation attributed to the dense coverage of the invasive alien Ageratina adenophora.This invasive species resulted in a reduction of understory species diversity.Additionally,our analysis uncovered a significant negative correlation in phylogenetic relatedness(net relatedness index)between native and invasive alien plant species in eastern Yunnan.This suggests closely related invasive species face heightened competition,hindering successful invasion.Taken together,our findings indicate that successful establishment and habitat restoration of K.evelyniana seedling/saplings require effective measures to control invasive plants. 展开更多
关键词 Keteleeria evelyniana Age structure Regeneration Species diversity Invasive alien species Phylogenetic relatedness
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How inflammation influences psychiatric disease
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作者 Eduardo Ferat-Osorio JoséLuis Maldonado-García Lenin Pavón 《World Journal of Psychiatry》 SCIE 2024年第3期342-349,共8页
Recent studies highlight the strong correlation between infectious diseases and the development of neuropsychiatric disorders.In this editorial,we comment on the article“Anti-infective therapy durations predict psych... Recent studies highlight the strong correlation between infectious diseases and the development of neuropsychiatric disorders.In this editorial,we comment on the article“Anti-infective therapy durations predict psychological stress and laparoscopic surgery quality in pelvic abscess patients”by Zhang et al,published in the recent issue of the World Journal of Psychiatry 2023;13(11):903-911.Our discussion highlighted the potential consequences of anxiety,depression,and psychosis,which are all linked to bacterial,fungal,and viral infections,which are relevant to the impact of inflammation on the sequelae in mental health as those we are observing after the coronavirus disease 2019 pandemic.We focus specifically on the immune mechanisms triggered by inflammation,the primary contributor to psychiatric complications.Importantly,pathophysiological mechanisms such as organ damage,post-injury inflammation,and infectioninduced endocrine alterations,including hypocortisolism or autoantibody formation,significantly contribute to the development of chronic low-grade inflammation,promoting the emergence or development of psychiatric alterations in susceptible individuals.As inflammation can have long-term effects on patients,a multidisciplinary treatment plan can avoid complications and debilitating health issues,and it is crucial to recognize and address the mental health implications. 展开更多
关键词 INFLAMMATION INFECTION DEPRESSION Pelvic inflammatory disease Psychiatric complication
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Phagocytosis: A Practical Approach for Evaluating Neutrophil Function in Health and Disease
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作者 Oscar Rojas-Espinosa Patricia Arce-Paredes +2 位作者 Sergio Islas-Trujillo Luis Enrique Becerril-Villanueva María Dolores Ponce-Regalado 《Modern Research in Inflammation》 2024年第2期9-28,共20页
Neutrophils, crucial players in the effector phase of the immune response, are recognized as important mediators of both innate and adaptive immune responses. Through the production of pro- and anti-inflammatory cytok... Neutrophils, crucial players in the effector phase of the immune response, are recognized as important mediators of both innate and adaptive immune responses. Through the production of pro- and anti-inflammatory cytokines, they modulate the function of T and other lymphoid cells. Countless reports have highlighted the importance of these cells as efficient antimicrobial agents and annotated their involvement in the pathology of infectious and noninfectious diseases. The development of modern, sophisticated technologies has allowed the study of the functions of these cells in clinical settings. These advanced technologies include fluorescence-activated cell sorters, confocal microscopy, automated cell image analyzers, and live cell analysis instruments. Unfortunately, the cost of these modern instruments, maintenance, reagents, and the need for qualified technicians prohibit their use in low-income laboratories and universities in developing countries. With this in mind, we propose a series of basic tests that can be used in low-input clinical laboratories and universities to evaluate the function of neutrophils in health and disease. Our methodology allows us to assess in a practical and low-cost manner the functions of neutrophils in the phagocytic process, including opsonization, ingestion, ROI production (NBT reduction), myeloperoxidase content, phagosome-lysosome fusion, microbicidal activity, and NET production. Thus, under a disadvantageous ambiance, this may guide physicians in deciding whether a patient’s illness involves phagocytic defects without imposing a heavy financial burden.Graphical Abstract[-rId13-] 展开更多
关键词 PHAGOCYTOSIS NEUTROPHILS Microbicidal Activity Netosis
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Multiphasic characterization of a plant growth promoting bacterial strain, Burkholderia sp.7016 and its effect on tomato growth in the field 被引量:13
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作者 GAO Miao ZHOU Jian-jiao +3 位作者 WANG En-tao CHEN Qian XU Jing SUN Jian-guang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第9期1855-1863,共9页
Aiming at searching for plant growth promoting rhizobacteria (PGPR), a bacterium strain coded as 7016 was isolated from soybean rhizosphere and was characterized in the present study. It was identiifed as Burkholderia... Aiming at searching for plant growth promoting rhizobacteria (PGPR), a bacterium strain coded as 7016 was isolated from soybean rhizosphere and was characterized in the present study. It was identiifed as Burkholderia sp. based on 16S rDNA sequence analysis, as wel as phenotypic and biochemical characterizations. This bacterium presented nitrogenase activity, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity and phosphate solubilizing ability;inhibited the growth of Sclerotinia sclerotiorum, Gibberel a zeae and Verticil ium dahliae;and produced smal quantities of indole acetic acid (IAA). In green house experiments, signiifcant increases in shoot height and weight, root length and weight, and stem diameter were observed on tomato plants in 30 d after inoculation with strain 7016. Result of 16S rDNA PCR-DGGE showed that 7016 survived in the rhizosphere of tomato seedlings. In the ifeld experiments, Burkholderia sp. 7016 enhanced the tomato yield and signiifcantly promoted activities of soil urease, phosphatase, sucrase, and catalase. Al these results demonstrated Burkholderia sp. 7016 as a valuable PGPR and a candidate of biofertilizer. 展开更多
关键词 PGPR Burkholderia sp. multiphasic characterization promoting growth BIOFERTILIZER
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Diversity, Endemism and Conservation of Ferns(Polypodiales) in the Mexican Mountain Component 被引量:2
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作者 SANGINéS-FRANCO Celia LUNA-VEGA Isolda +3 位作者 CONTRERAS-MEDINA Raúl ESPINOSA David TEJERO-DíEZ José Daniel RIVAS Gerardo 《Journal of Mountain Science》 SCIE CSCD 2015年第4期891-904,共14页
We analyzed the distributional patterns of95 selected species of leptosporangiate ferns inhabiting the Mexican Mountain Component, using grid-cells of one geographical degree as unit areas,applying endemism indices an... We analyzed the distributional patterns of95 selected species of leptosporangiate ferns inhabiting the Mexican Mountain Component, using grid-cells of one geographical degree as unit areas,applying endemism indices and richness and beta diversity analyses.Distributional data were obtained from several herbaria and specialized literature.Five grid-cells appear to be important for fern species richness, as they contain 35 to 49 species.These gridcells are located in the Sierra Madre Oriental(SMO),Trans-Mexican Volcanic Belt(TMVB) and the Sierra Madre del Sur(SMS).Mean richness by latitudinal belts of one degree showed that the belts with highest values are related to the TMVB and SMS.A total of 13grid-cells were recognized as important from theperspective of endemism; most of them are located also in the SMO, TMVB and SMS.The richest gridcells coincided with one of the main centres of endemism for ferns obtained in this study, located in the convergence of the southern part of the SMO, the eastern portion of the TMVB and the northern part of the SMS, reflecting the high humidity existing on the mountain slopes facing the Gulf of Mexico.Some important grid-cells recognized from richness and endemism analyses coincide with Mexican Natural Protected Areas.The beta diversity analysis showed a low degree of similarity among grid-cells, implying a high species replacement, as the result of environmental heterogeneity occurring in the Mexican mountain systems.On the other hand, the spatial analysis suggested a pattern of phytogeographical regionalization comprising twomain areas: the Mexican Transition Zone and the Mexican Central Plateau.Ferns play an important role in the Mexican biodiversity and contributing to the beta diversity of Mexico. 展开更多
关键词 BIOGEOGRAPHY Distributional patterns Leptosporangiate ferns Mexico
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Hepatoprotective effect of Geranium schiedeanum against ethanol toxicity during liver regeneration 被引量:1
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作者 Eduardo Madrigal-Santillán Mirandeli Bautista +8 位作者 Juan A Gayosso-De-Lucio Yadira Reyes-Rosales Araceli Posadas-Mondragón ángel Morales-González Marvin A Soriano-Ursúa Jazmín García-Machorro Eduardo Madrigal-Bujaidar Iselaálvarez-González JoséA Morales-González 《World Journal of Gastroenterology》 SCIE CAS 2015年第25期7718-7729,共12页
AIM: To evaluate the effect of an extract of Geranium schiedeanum(Gs) as a hepatoprotective agent against ethanol(Et OH)-induced toxicity in rats. METHODS: Male Wistar rats weighing 200-230 g were subjected to a 70% p... AIM: To evaluate the effect of an extract of Geranium schiedeanum(Gs) as a hepatoprotective agent against ethanol(Et OH)-induced toxicity in rats. METHODS: Male Wistar rats weighing 200-230 g were subjected to a 70% partial hepatectomy(PH); they were then divided into three groups(groups 1-3). During the experiment, animals in group 1 drank only water. The other two groups(2-3) drank an aqueous solution of Et OH(40%, v/v). Additionally, rats in group 3 received a Gs extract daily at a dose of 300 mg/kg body weight intragastically. Subsequently, to identify markers of liver damage in serum, alanine aminotransferase, aspartate aminotransferase, albumin and bilirubin were measured by colorimetric methods. Glucose, triglyceride and cholesterol concentrations were also determined. In addition, oxidative damage was estimated by measuring lipid peroxidation [using thiobarbituric-acid reactive substances(TBARS)] in both plasma and the liver and by measuring the total concentration of antioxidants in serum and the total antioxidant capacity in the liver. In addition, a liver mass gain assessment, total DNA analysis and a morpho-histological analysis of the liver from animals in all three groups were performed and compared. Finally, the number of deaths observed in the three groups was analyzed.RESULTS: Administration of the Geranium shiedeanum extract significantly reduced the unfavorable effect of ethanol on liver regeneration(restitution liver mass: PHEt OH group 60.68% vs PH-Gs-Et OH group 69.22%). This finding was congruent with the reduced levels of hepatic enzymes and the sustained or increased levels of albumin and decreased bilirubin in serum. The extract also modified the metabolic processes that regulate glucose and lipid levels, as observed from the serum measurements. Lower antioxidant levels and the liver damage induced by Et OH administration appeared to be mitigated by the extract, as observed from the TBARs(PH-Et OH group 200.14 mmol/mg vs PH-Gs-Et OH group 54.20 mmol/mg; P < 0.05), total status of antioxidants(PH-Et OH group 1.43 mmol/L vs PH-Gs-Et OH group 1.99 mmol/L; P < 0.05), total antioxidant capacity values, liver mass gain and total DNA determination(PH-Et OH group 4.80 mg/g vs PH-Gs-Et OH 9.10 mg/g; P < 0.05). Overall, these processes could be related to decreased mortality in these treated animals.CONCLUSION: The administered extract showed a hepatoprotective effect, limiting the Et OH-induced hepatotoxic effects. This effect can be related tomodulating oxido-reduction processes. 展开更多
关键词 GERANIUM schiedeanum Liver REGENERATION ETHANOL Free RADICALS NUCLEAR factor erythroid-2-relatedfactor 2
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Biocompatibility and electrochemical evaluation of ZrO_(2) thin films deposited by reactive magnetron sputtering on MgZnCa alloy 被引量:1
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作者 Benjamín Millán-Ramos Daniela Morquecho-Marín +8 位作者 Phaedra Silva-Bermudez David Ramírez-Ortega Osmary Depablos-Rivera Julieta García-López Mariana Fernández-Lizárraga JoséVictoria-Hernández Dietmar Letzig Argelia Almaguer-Flores Sandra E.Rodil 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2021年第6期2019-2038,共20页
Biodegradable magnesium alloys are promising candidates for temporary fracture fixation devices in orthopedics;nevertheless,its fast degradation rate at the initial stage after implantation remains as one of the main ... Biodegradable magnesium alloys are promising candidates for temporary fracture fixation devices in orthopedics;nevertheless,its fast degradation rate at the initial stage after implantation remains as one of the main challenges to be resolved.ZrO_(2)-based coatings to reduce the degradation rate of the Mg-implants are an attractive solution since they show high biocompatibility and stability.In this work,the degradation,cytotoxicity,and antibacterial performance of ZrO_(2)thin films deposited by magnetron sputtering on a Mg-Zn-Ca alloy was evaluated.Short-term degradation of ZrO_(2)-coated and uncoated samples was assessed considering electrochemical techniques and H_(2)evolution(gas chromatography).Additionally,long term degradation was assessed by mass-loss measurements.The results showed that a 380 nm ZrO_(2)coating reduces the degradation rate and H_(2)evolution of the alloy during the initial 3 days after immersion but allows the degradation of the bare alloy for the long-term.The ZrO_(2)coating does not compromise the biocompatibility of the alloy and permits better cell adhesion and proliferation of mesenchymal stem cells directly on its surface,in comparison to the bare alloy.Finally,the ZrO_(2)coating prevents the adhesion and biofilm formation of S.aureus. 展开更多
关键词 Zirconium dioxide Magnetron sputtering Short-term degradation H_(2)evolution
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Tree community composition,structure and diversity along an elevational gradient in an Andean forest of Northern Ecuador
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作者 JIMÉNEZ-PAZ Rosa WORTHY Samantha J +4 位作者 VALENCIA Renato PÉREZÁlvaro J REYNOLDS Alex BARONE John A BURGESS Kevin S 《Journal of Mountain Science》 SCIE CSCD 2021年第9期2315-2327,共13页
The Andean forests of northern Ecuador are known for their high levels of plant diversity relative to the area they occupy.Typically,these forests grow on steep slopes that lead to dramatic habitat gradients across sh... The Andean forests of northern Ecuador are known for their high levels of plant diversity relative to the area they occupy.Typically,these forests grow on steep slopes that lead to dramatic habitat gradients across short distances.These extreme habitat gradients make the Andean forest ecosystem an excellent natural laboratory for understanding the effect of elevation on forest community diversity,structure and composition.We established 31 plots(50 m×5 m)which are divided between two elevational transects in the cloud forest of the Siempre Verde Reserve in the western foothills of the Andes Mountains of northern Ecuador.All trees and tree ferns with a diameter at breast height(dbh)≥5 cm were measured and identified.We examined changes in community composition,structure,and diversity along and between the elevational transects and three elevational zones:low(2437–2700 m),middle(2756–3052 m),and high(3163–3334 m).We found four main trends associated with the elevational gradients at this site:(1)community composition differed between the two transects and among the three elevational zones according to N-MDS,ANOSIM,and percentage of shared species,with some species having limited distributions,(2)metrics of community structure showed opposite relationships with elevation,depending on the transect,with the only significant relationship(negative)found between basal area and elevation in the open trail transect,(3)alpha diversity,in general,peaked at mid-elevations,and(4)beta diversity consistently increased with distance between plots along elevation.The complexity of changes in community composition,structure,and alpha diversity along elevation may be related to the heterogeneity of the environment on a local scale,such as topography,soil composition,and even human impact,or to dispersal limitation and should be investigated further.These changes in community composition and the relatively high beta diversity found at this site exemplify the biological complexity of montane forest,reinforcing arguments from other studies on the importance of their conservation. 展开更多
关键词 Elevational gradient Cloud forest ANDES STRUCTURE Composition DIVERSITY
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Cerebral dopamine neurotrophic factor transfection in dopamine neurons using neurotensin-polyplex nanoparticles reverses 6-hydroxydopamine-induced nigrostriatal neurodegeneration 被引量:1
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作者 Manuel A.Fernandez-Parrilla David Reyes-Corona +15 位作者 Yazmin M.Flores-Martinez Rasajna Nadella Michael J.Bannon Lourdes Escobedo Minerva Maldonado-Berny Jaime Santoyo-Salazar Luis O.Soto-Rojas Claudia Luna-Herrera Jose Ayala-Davila Juan A.Gonzalez-Barrios Gonzalo Flores Maria E.Gutierrez-Castillo Armando JEspadas-Alvarez Irma A.Martínez-Dávila Porfirio Nava Daniel Martinez-Fong 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第4期854-866,共13页
Overexpression of neurotrophic factors in nigral dopamine neurons is a promising approach to reverse neurodegeneration of the nigrostriatal dopamine system,a hallmark in Parkinson's disease.The human cerebral dopa... Overexpression of neurotrophic factors in nigral dopamine neurons is a promising approach to reverse neurodegeneration of the nigrostriatal dopamine system,a hallmark in Parkinson's disease.The human cerebral dopamine neurotrophic factor(h CDNF)has recently emerged as a strong candidate for Parkinson's disease therapy.This study shows that h CDNF expression in dopamine neurons using the neurotensinpolyplex nanoparticle system reverses 6-hydroxydopamine-induced morphological,biochemical,and behavioral alterations.Three independent electron microscopy techniques showed that the neurotensin-polyplex nanoparticles containing the h CDNF gene,ranging in size from 20 to 150 nm,enabled the expression of a secretable h CDNF in vitro.Their injection in the substantia nigra compacta on day 21 after the 6-hydroxydopamine lesion resulted in detectable h CDNF in dopamine neurons,whose levels remained constant throughout the study in the substantia nigra compacta and striatum.Compared with the lesioned group,tyrosine hydroxylase-positive(TH^(+))nigral cell population and TH+fiber density rose in the substantia nigra compacta and striatum after h CDNF transfection.An increase inβIII-tubulin and growth-associated protein 43 phospho-S41(GAP43 p)followed TH^(+)cell recovery,as well as dopamine and its catabolite levels.Partial reversal(80%)of drugactivated circling behavior and full recovery of spontaneous motor and non-motor behavior were achieved.Brain-derived neurotrophic factor recovery in dopamine neurons that also occurred suggests its participation in the neurotrophic effects.These findings support the potential of nanoparticle-mediated h CDNF gene delivery to develop a disease-modifying treatment against Parkinson's disease.The Institutional Animal Care and Use Committee of Centro de Investigación y de Estudios Avanzados approved our experimental procedures for animal use(authorization No.162-15)on June 9,2019. 展开更多
关键词 axonal growth brain-derived neurotrophic factor gene delivery NANOPARTICLES NEURITOGENESIS neuronal cytoskeleton neuroregeneration neurorestoration neurotrophic therapy Parkinson's disease REINNERVATION substantia nigra
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Serum levels of chemokines in adolescents with major depression treated with fluoxetine 被引量:1
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作者 Francisco Rafael de la Peña Carlos Cruz-Fuentes +9 位作者 Lino Palacios Manuel Iván Girón-Pérez Emilio Medina-Rivero Maria Dolores Ponce-Regalado Samantha Alvarez-Herrera Gilberto Pérez-Sánchez Enrique Becerril-Villanueva JoséLuis Maldonado-García María C Jiménez-Martínez Lenin Pavón 《World Journal of Psychiatry》 SCIE 2020年第8期175-186,共12页
BACKGROUND Major depressive disorder(MDD)is a global health issue that affects 350 million people of all ages.Although between 2%and 5.6%of affected individuals are adolescents,research on young patients is limited.Th... BACKGROUND Major depressive disorder(MDD)is a global health issue that affects 350 million people of all ages.Although between 2%and 5.6%of affected individuals are adolescents,research on young patients is limited.The inflammatory response contributes to the onset of depression,and in adult MDD patients,symptom severity has been linked to chemokine levels.AIM To determine the differences in circulatory levels of chemokines in healthy volunteers(HVs)and adolescents with MDD,and assess the changes induced by fluoxetine consume.METHODS The 22 adolescents with MDD were monitored during the first 8 wk of clinical follow-up and clinical psychiatric evaluation was done using the Hamilton depresión rating scale(HDRS).The serum levels of monocyte chemoattractant protein-1(MCP-1),macrophage inflammatory protein(MIP)-1α,MIP-1β,interleukin(IL)-8,interferon gamma-induced protein(IP)-10,and eotaxin were measured in patients and HVs.RESULTS In all cases,significant differences were detected in circulating chemokine levels between patients before treatment and HVs(P<0.0001).All chemokines decreased at 4 wk,but only MCP-1 and IL-8 significantly differed(P<0.05)between 0 wk and 4 wk.In the patients,all chemokines rose to their initial concentrations by 8 wk vs 0 wk,but only IP-10 did so significantly(P<0.05).All patients experienced a significant decrease in HDRS scores at 4 wk(P<0.0001)and 8 wk(P<0.0001)compared with 0 wk.CONCLUSION Despite the consumption of fluoxetine,patients had significantly higher chemokine levels,even after considering the improvement in HDRS score.The high levels of eotaxin,IP-10,and IL-8 partially explain certain aspects that are affected in MDD such as cognition,memory,and learning. 展开更多
关键词 Adolescents Major depression CHEMOKINE FLUOXETINE Interferon gammainduced protein-10
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Wilt Disease of Tara (<i>Caesalpinia spinose</i>Molina Kuntz) in Nursery in the Inter Andean Valley of Cochabamba, Bolivia
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作者 Mario Coca Morante 《American Journal of Plant Sciences》 2018年第9期1963-1973,共11页
Tara (Caesalpinia spinose Molina Kuntz) is a native plant of the Bolivian Andes. A number of projects have promoted the cultivation of this species over the last 20 years, in efforts to make use of its medicinal, food... Tara (Caesalpinia spinose Molina Kuntz) is a native plant of the Bolivian Andes. A number of projects have promoted the cultivation of this species over the last 20 years, in efforts to make use of its medicinal, food and industrial properties. However, as tara plantations have grown, so too has the incidence of disease affecting the species, leading to economic losses. The aim of the present work was to identify the causal agent of wilting in tara, and to determine the incidence of the disease in nursery-grown plants. Three experimental plots (R1-R3) were established in plantlet production bedsat the ESFOR nursery in order to assess the incidence of wilting. Plant spacing was 1 × 1 m. At the two leaf stage, samples of diseased and apparently healthy plants were taken to the laboratory for the isolation of pathogens. Both the apparently healthy and diseased plants gave rise to the same kinds of fungal colony on PDA. Microscopic examination revealed microconidia, macroconidia, phialides and chlamydospores suggesting the causal agent to be Fusarium oxysporum. Over the (up to) 84-day period following thinning, the incidence of wilting for 2010 was R1 = 2.56%, R2 = 3.15% and R3 = 2.22% per 14 days, and for 2013 it was R1 = 1.24%, R2 = 2.45% and R3 = 2.13% per 14 days;the apparent infection rates for 2010 were rR1 = 0.0003/day, rR2 = 0.0003/day and rR3 = 0.0003/day, and for 2013 they were rR1 = 0.0003/day, rR2 = 0.0004/day and rR3 = 0.0003/day. These values are characteristic of monocyclic epiphytic fungi such as F. oxysporum. 展开更多
关键词 Soil Pathogens Monocyclic Epiphytic Fungi Disease Intensity FUSARIUM OXYSPORUM
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Morphological and biochemical effects of weekend alcohol consumption in rats: Role of concentration and gender
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作者 José A Morales-González María de Lourdes Sernas-Morales +8 位作者 ángel Morales-González Laura Ligía González-López Eduardo Osiris Madrigal-Santillán Nancy Vargas-Mendoza Tomás Alejandro Fregoso-Aguilar Liliana Anguiano-Robledo Eduardo Madrigal-Bujaidar Isela álvarez-González Germán Chamorro-Cevallos 《World Journal of Hepatology》 CAS 2018年第2期297-307,共11页
AIM To examine the association between weekend alcohol consumption and the biochemical and histological alterations at two different concentrations of alcohol in both genders in rats.METHODS Wistar rats weighing 170-2... AIM To examine the association between weekend alcohol consumption and the biochemical and histological alterations at two different concentrations of alcohol in both genders in rats.METHODS Wistar rats weighing 170-200 g were divided into groups as follows:(1) Control groups; and(2) weekend alcohol-consumption group: 2 d/weekly per 12 wk, at two different concentrations:(1) Group of males or females with a consumption of a solution of alcohol at 40%; and(2) group of males or females with a consumption of a solution of alcohol at 5%. At the end of the experiment, serum and liver samples were obtained. The following enzymes and metabolites were determined in serum: Alanine Aminotransferase(ALT), Aspartate Aminotransferase(AST), Lactate Dehydrogenase, and Gamma-Glutamyltransferase, and glucose, triglycerides, cholesterol, bilirubin, and albumin. Liver samples from each group were employed to analyze morphological abnormalities by light microscopy.RESULTS In all of the weekend alcohol-consumption groups, AST activity presented a significant, 10-fold rise. Regarding ALT activity, the groups with weekend alcohol consumption presented a significant increase that was six times greater. Bilirubin levels increased significantly in both groups of females. We observed a significant increase in the parameters of fatty change and inflammation due to weekend alcohol consumption. Only the group of females that consumed alcohol at 40% presented slight hepatocel ular disorganization CONCLUSION The results obtained herein provide solid evidence that weekend alcohol consumption gives rise to liver damage, demonstrated by biochemical and histological alterations, first manifested acutely, and prolonged weekend alcohol consumption can cause greater, irreversible damage. 展开更多
关键词 WEEKEND ALCOHOL CONSUMPTION Liver morphology TRANSAMINASES Damage
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Genome-wide comparison inferred the origin and evolution of B-cell epitopes on the proteins of human influenza A virus
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作者 Edgar E. Lara-Ramírez Aldo Segura-Cabrera +2 位作者 Ma. Isabel Salazar Mario A. Rodríguez-Pérez Xianwu Guo 《Health》 2012年第10期946-954,共9页
The novel strain H1N1 caused the outbreak of first pandemic influenza in 21 century. Now it is a common component of current seasonal influenza viruses. The recent transmission and plentiful genome sequences available... The novel strain H1N1 caused the outbreak of first pandemic influenza in 21 century. Now it is a common component of current seasonal influenza viruses. The recent transmission and plentiful genome sequences available provided a good opportunity to study the origin and evolution of epitopes on the proteins of human influenza virus. In the present study, the B-cell epitope compositions in the pandemic strains, circulating traditional seasonal strains, swine strains as well as highly virulent avian strain H5N1 were identified with the aid of the Immune Epitope DataBase (IEDB) and were compared at genomic level. A total of 14210 distinct sequences down-loaded from NCBI database were used for analysis. Some epitopes on proteins HA or NA, not conserved in recent seasonal strains, were found in 2009 pandemic strains but existed in the early human strains (1919-1935). The pandemic strain shared higher conserved epitopes with “bird flu” virus H5N1than classic human seasonal strains. The epitopes that could exist at common antigenic regions of HA protein are needed to further identify. The genetic exchanges between human and swine population by transmission was very active but the princepal side of the transmission could be from swine to human. These results provided valuable information on influenza A virus evolution and transmission by means of epitope analysis at genomic level. 展开更多
关键词 INFLUENZA A Virus H1N1 PANDEMIC EPITOPES Genome COMPARISON
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The effect of alpha asarone, olive oil, and dexamethasone on collagen-induced arthritis (CIA) in the mouse
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作者 Mayda Yanik Aquino-Vega Lorena Rodríguez-Páez +3 位作者 Patricia Arce-Paredes Víctor G. Hernández-Chávez Enrique Becerril-Villanueva Oscar Rojas-Espinosa 《Modern Research in Inflammation》 2013年第1期9-20,共12页
Aim of the Study: The primary aim of the study was to test the effect of 2,4,5-trimethoxy-1-propenylbenzene (alpha asarone), a hypocholes terolaemic drug, on the progression of collagen induced arthritis (CIA) in mice... Aim of the Study: The primary aim of the study was to test the effect of 2,4,5-trimethoxy-1-propenylbenzene (alpha asarone), a hypocholes terolaemic drug, on the progression of collagen induced arthritis (CIA) in mice. Olive oil,the vehicle of alpha-asarone, and dexamethasonewere used as control treatments. Set-Up: Four groups of DBA/1 mice were immunised with chicken type II collagen (CII) via the intradermal route and either left untreated or were treated with alpha asarone, olive oil, or dexamethasone. A non-immunised group was an additional control. Follow-Up: The thicknesses of the rear and front footpads were continuously monitored, and the levels of anti-collagen antibodies were measured at the end of the experiment. The animals were then sacrificed, and their rear and front limbs were removed and processed forhistological examination. Results: Alpha asarone had no anti-inflammatory effect on CIA, and in one third of the animals, it showed a proinflammatory effect that was characterised by a marked accumulation of neutrophils. Olive oil did not show any obvious antiinflammatory effect on CIA, but it lowered the level of CII antibodies by 50%, suggesting a potential long-term antiinflammatory effect. As expected, dexamethasone had a clear anti-inflammatory effect on CIA. Con- clusion: Alpha asarone did not show any antiinflammatory effect on CIA in the mice under the above conditions;however, the accumulation of neutrophils in the CIA lesions of mice treated with alpha asarone and the effect of olive oil in downregulating the levels of anti-CII antibodies in CIA are two findings that warrant further investigation. 展开更多
关键词 Collagen ARTHRITIS MOUSE ASARONE OLIVE Oil DEXAMETHASONE
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Protective Effect of Phenolic-Rich Extracts from Different Parts of <i>Opuntia joconostle</i>Fruit against Carbon Tetrachloride-Induced Oxidative Stress in Mice
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作者 Obed Osorio-Esquivel Alicia Ortiz-Moreno +1 位作者 Julieta Herrera-Martínez María Dolores Hernández-Navarro 《Journal of Biomaterials and Nanobiotechnology》 2013年第3期35-42,共8页
Opuntia joconostle fruit is a rich source of biocompounds such as polyphenols including gallic, vanilic, 4-hidroxybenzoic, cafeic, and syringic acids, catechin, epicatechin, rutin, and vanillin, besides betalains. The... Opuntia joconostle fruit is a rich source of biocompounds such as polyphenols including gallic, vanilic, 4-hidroxybenzoic, cafeic, and syringic acids, catechin, epicatechin, rutin, and vanillin, besides betalains. The objective of this research was to evaluate the effect of supplementation polyphenols-rich extracts from different parts of Opuntia joconostle against carbon tetrachloride-induced oxidative stress in a mouse model. The animals were treated orally with polyphenols-rich extracts at 50, 100 and 200 mg/kg BW for 30 consecutive days. On day 30th the mice received carbon tetrachloride (CCl4) as hepatoxic agent. Biochemical evaluations were carried out 24 h after induction of the oxidative stress. Data showed that methanolic extracts from different parts of Opuntia joconostle exerting protective effect against the CCl4-induced oxidative stress in mice. Histology examination revealed that the damage decreased in groups treated with polyphenols-rich extracts compared to the group that did not receive any treatment. Opuntia joconostle fruit contains many phenolic compounds, flavonoids and betalains. The protective effect of extracts may be related to the phenolic composition and also by a counteraction with other compounds, such as betalains and flavonoids that increase their antioxidant effect. 展开更多
关键词 OPUNTIA joconostle Oxidative Stress Carbon TETRACHLORIDE Phenolic Compounds
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Renin-angiotensin system blockade: Effect on renal mRNA expression in 5/6 nephrectomized rats
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作者 Erika Yadira Cruz-Laguna Ana Ma. Gámez-Méndez +3 位作者 Hilda Vargas-Robles Amelia Ríos Alfonso Méndez-Tenorio Bruno Escalante 《Health》 2013年第4期9-15,共7页
The aim of this study was to determinate the gene expression levels of angiotensinogen, angiotensin converting enzyme, renin, (pro)renin receptor, and the final rennin-angiotensin system (RAS) products Angiotensin (An... The aim of this study was to determinate the gene expression levels of angiotensinogen, angiotensin converting enzyme, renin, (pro)renin receptor, and the final rennin-angiotensin system (RAS) products Angiotensin (Ang) II and Ang 1-7 inthe remnant kidney of 5/6 nephrectomized rats and its response to RAS pharmacological blockade. Male Wistar rats were divided into five groups: sham operated (SO), 5/6 nephrectomized (NFX), NFX + captopril (50 mg/ kg/day), NFX + losartan (10 mg/kg/day), and NFX + aliskiren (10 mg/kg/day). Animals were followed up for 60 days and protein urine excretion was measured. Systolic blood pressure, renal tissue RAS mRNA expression levels, plasma Ang II, and plasma Ang 1-7 were evaluated at day 60 after nephrectomy. Blood pressure and urine protein were increased after 5/6 nephrectomy. Ang II levels were increased 9.4 fold, whereas Ang 1-7 decreased 72.9% in NFX animals compared with SO rats. 5/6 nephrectomy increased renal angiotensinogen and (pro)renin receptor mRNA expression but down-regulated renin mRNA expression. RAS blockade restored the systolic blood pressure to normal values and slowed down urinary protein excretion, and also prevented changes in Ang II and Ang 1-7. RAS blockade reduced (pro)renin receptor, ACE, and AGT mRNA expression in the remnant kidney. However, renin mRNA expression increased compared with NFX rats. In conclusion these results suggest that inhibition of Ang II synthesis by RAS blockade is associated with renal regulation of RAS mRNA expression and this may be through a mechanism related with the Ang II/Ang 1-7 balance. 展开更多
关键词 ANGIOTENSIN II ANGIOTENSIN 1-7 ACE RAS BLOCKADE
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