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Iron toxicity resistance strategies in tropical grasses:The role of apoplastic radicular barriers

Journal of Environmental Sciences 2019年第4期31卷 257-266页

作者： Advanio Inacio Siqueira-silva Camilla Oliveira Rios Eduardo Gusmao pereira Institute of Biological and Health Sciences Federal University of Vicosa (UFV)Campus Florestal Minas Gerais Brazil Federal University of Western Para (UFOPA) University Campus of JurutiPara Brazil Postgradute Program in Management and Conservation of Natural and Agrarian Ecosystems UFV Campus Florestal Florestal Minas Gerais Brazil

The revegetation of mined areas poses a great challenge to the iron ore mining *** initial recovery process in degraded areas might rely on the use of Fe-resistant *** grasses, such as Paspalum densum and Echinochloa crus-galli, show different resistance strategies to iron toxicity; however, these mechanisms are poorly *** Fe-resistance mechanisms and direct iron toxicity as a function of root apex removal were investigated. To achieve this purpose, both grass species were grown for up to 480 hr in a nutrient solution containing 0.019 or 7 mmol/L Fe-EDTA after the root apices had been removed or maintained. Cultivation in the presence of excess iron-induced leaf bronzing and the formation of iron plaque on the root surfaces of both grass species, but was more significant on those plants whose root apex had been removed. Iron accumulation was higher in the roots, but reached phytotoxic levels in the aerial parts as well. It did not hinder the biosynthesis of chloroplastidic pigments. No significant changes in gas exchange and chlorophyll a fluorescence occurred in either grass when their roots were kept intact; the contrary was true for plants with excised root apices. In both studied grasses, the root apoplastic barriers had an important function in the restriction of iron translocation from the root to the aerial plant parts, especially in E. crus-galli. Root apex removal negatively influenced the iron toxicity resistance mechanisms(tolerance in P. densum and avoidance in E. crus-galli).

关键词： Paspalum densum Echinochloa crus-galli Apoplastic barrier Iron toxicity

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Entropy model to assess sediment resuspension probability and trap efficiency of small dams

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International Journal of Sediment Research 2022年第5期37卷 675-686页

作者： Francisco Jairo Soares pereira Antonio Viana da silva Filho José Wellington Batista Lopes José Carlos de Araújo Department of Agricultural Engineering Federal University of Ceará Campus Do Pici Rural Federal University of Pernambuco Federal University of Piauí

In the Brazilian drylands, there are tens of thousands of small dams. Despite their paramount importance to the rural population, they are rarely monitored. Water demand increases with time while, simultaneously, siltation reduces reservoir water capacity and availability. Reservoir siltation models are, therefore, mandatory to manage the numerous ungauged small dams in these *** objective of the current study is to improve sediment trap efficiency(TE) modeling by including resuspension as a key probabilistic process. The Shannon entropy was used to estimate the sediment resuspension probability, which was merged with the Camp model and generated the RETSED entropy model. To validate the RETSED model, an experimental check dam(ECD, 300 m3), located in the Gilbu es desertification site, Brazil, was monitored hourly during one hydrological year(July 2018-July 2019). Measurements show that the annual volumetric decline of the check dam was 12%; and that the average trap efficiency equaled 86%. Only 9.5% of the hourly sediment concentration outflow exceeded the average plus one standard deviation, showing that the reservoir is well mixed; a fact which highlights the relevance of the resuspension process. Three empirical models failed to mimic the experimental results: Churchill(TE = 99%), Brune(TE = 75%), and Maryland(TE = 94%). According to the RETSED entropy model, the resuspension probability during the experiment was 10%and TE = 81%, a value only 6% below the measured one. The Camp model simulated TE = 89%, only 3%higher than the measured value, but confirmed the Camp model’s tendency to overestimate TE due to a disregard of resuspension. The deterministic model showed low sensitivity concerning the hydrodynamic effects, whereas the entropy formulation proved to be more consistent with physical behavior: the resuspension probability clearly increased and trap efficiency decreased with rising reservoir discharge.

关键词： Erosion Check dam Sedimentation Ungauged basins Camp model

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Renin-angiotensin system in the pathogenesis of liver fibrosis

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World Journal of Gastroenterology 2009年第21期15卷 2579-2586页

作者： Regina Maria pereira Robson Augusto Souza dos Santos Filipi Leles da Costa Dias Mauro Martins Teixeira Ana Cristina Simoes e silva Department of Pediatrics Faculty of MedicineFederal University of Minas Gerais Laboratory of Hypertension Department of Physiology and BiophysicsInstitute of Biological SciencesFederal University of Minas Gerais Laboratory of Immunopharmacology Department of Biochemistry and ImmunologyInstitute of Biological SciencesFederal University of Minas Gerais

Hepatic fibrosis is considered a common response to many chronic hepatic injuries. It is a multifunctional process that involves several cell types, cytokines, chemokines and growth factors leading to a disruption of homeostatic mechanisms that maintain the liver ecosystem. In spite of many studies regarding the development of fibrosis, the understanding of the pathogenesis remains obscure. The hepatic tissue remodeling process is highly complex, resulting from the balance between collagen degradation and synthesis. Among the many mediators that take part in this process, the components of the Renin angiotensin system （RAS） have progressively assumed an important role. Angiotensin （Ang） II acts as a profibrotic mediator and Ang-（1-7）, the newly recognized RAS component, appears to exert a counter-regulatory role in liver tissue. We briefly review the liver fibrosis process and current aspects of the RAS. This review also aims to discuss some experimental evidence regarding the participation of RAS mediators in the pathogenesis of liver fibrosis, focusing on the putative role of the ACE2-Ang-（1-7）- Mas receptor axis.

关键词： Hepatic fibrosis Renin angiotensin system Angiotensin II Angiotensin-(1-7) Receptor Mas Angiotensin converting enzyme 2

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Toxicity assessment of polyethylene microplastics in combination with a mix of emerging pollutants on Physalaemus cuvieri tadpoles

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Journal of Environmental Sciences 2023年第5期127卷 465-482页

作者： Amanda pereira da Costa Araújo Thiarlen Marinho da Luz Mohamed Ahmed Ibrahim Ahmed Mir Mohammad Ali Md.Mostafizur Rahman Bojan Nataraj daniela de Melo e silva damiàBarceló Guilherme Malafaia Post-Graduation Program in Environmental Sciences Federal University of GoiásGoianiaGO 74690-970Brazil Laboratory of Toxicology Applied to the Environment Goiano Federal InstituteUrutaíGO 75790-000Brazil Plant Protection Department Faculty of AgricultureAssiut UniversityAssiut 71526Egypt Department of Aquaculture Faculty of FisheriesAquaculture&Marine ScienceSher-e-Bangla Agricultural UniversityDhaka 1207Bangladesh Department of Environmental Sciences Jahangirnagar UniversitySavar 1342Bangladesh Unit of Toxicology Department of ZoologySchool of Life SciencesBharathiar UniversityCoimbatore 641046India Laboratory of Environmental Mutagenesis Federal University of GoiásGoianiaGO 74690-970Brazil Catalan Institute for Water Research(ICRA-CERCA) H_(2)O BuildingScientific and Technological Park of the University of GironaEmili Grahit 101Girona 17003Spain Water and Soil Quality Research Group Department of Environmental ChemistryInstitute of Environmental Assessment and Water Research(IDAEA-CSIC)JordiGirona 1826Barcelona 08034Spain Post-Graduation Program in Conservation of Cerrado Natural Resources Goiano Federal InstituteUrutaíGO 75790-000Brazil Post-Graduation Program in Ecology Conservationand BiodiversityFederal University of UberlandiaUberlandiaMG 38400-902Brazil Post-Graduation Programa in Biotechnology and Biodiversity Federal University of GoiásGoianiaGO 74605-050Brazil

Studies in recent years have shown that aquatic pollution by microplastics(MPs)can be considered to pose additional stress to amphibian ***,our knowledge of how MPs affect amphibians is very rudimentary,and even more limited is our understanding of their effects in combination with other emerging ***,we aimed to evaluate the possible toxicity of polyethylene MPs(PE-MPs)(alone or in combination with a mix of pollutants)on the health of Physalaemus cuvieri *** 30 days of exposure,multiple biomarkers were measured,including morphological,biometric,and developmental indices,behavioral parameters,mutagenicity,cytotoxicity,antioxidant and cholinesterase responses,as well as the uptake and accumulation of PE-MPs in *** on the results,there was no significant change in any of the parameters measured in tadpoles exposed to treatments,but induced stress was observed in tadpoles exposed to PE-MPs combined with themixture of pollutants,reflecting significant changes in physiological and biochemical *** principal component analysis(PCA)and integrated biomarker response(IBR)assessment,effects induced by pollutants in each test group were distinguished,confirming that the exposure of *** tadpoles to the PE-MPs in combination with a mix of emerging pollutants induces an enhanced stress response,although the uptake and accumulation of PE-MPs in these animalswas ***,our study provides newinsight into the danger to amphibians of MPs coexisting with other pollutants in aquatic environments.

关键词： Amphibians Environmental toxicology Micropollutants Emerging pollutants Aquatic pollution Biomarkers

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Engineering Improved Photosynthesis in the Era of Synthetic Biology

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Plant Communications 2020年第2期1卷 1-17页

作者： Willian Batista-silva Paula da Fonseca-pereira Auxiliadora Oliveira Martins Agustin Zsogon Adriano Nunes-Nesi Wagner L.Araujo Departamento de Biologia Vegetal Universidade Federal de Vic¸osaVic¸osaMinas Gerais 36570-900Brazil

Much attention has been given to the enhancement of photosynthesis as a strategy for the optimization of crop *** traditional plant breeding is most likely reaching a plateau,there is a timely need to accelerate improvements in photosynthetic efficiency by means of novel tools and biotechnological *** emerging field of synthetic biology offers the potential for building completely novel pathways in predictable directions and,thus,addresses the global requirements for higher yields expected to occur in the 21st ***,we discuss recent advances and current challenges of engineering improved photosynthesis in the era of synthetic biology toward optimized utilization of solar energy and carbon sources to optimize the production of food,fiber,and fuel.

关键词： photosynthesis synthetic biology genetic engineering yield improvement targeted manipulation

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Lactobacillus bulgaricus inhibits colitis-associated cancer via a negative regulation of intestinal inflammation in azoxymethane/dextran sodium sulfate model

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World Journal of Gastroenterology 2020年第43期26卷 6782-6794页

作者： Denise Sayuri Calheiros Silveira Luciana Chain Veronez Luis Carlos Lopes-Junior Elen Anatriello Mariangela Ottoboni Brunaldi Gabriela pereira-da-silva Department of Biochemistry and Immunology University of São Paulo at Ribeirão Preto Medical SchoolRibeirão Preto 14049-900SPBrazil Health Sciences Center Federal University of Espírito Santo-UFESVitória 29043-900ESBrazil Institute of Science and Technology Federal University of São PauloUNIFESPSão Josédos Campos 12231-280SPBrazil Department of Pathology and Forensic Medicine University of São PauloRibeirao Preto 14040-902SPBrazil Department of Maternal-Infant Nursing and Public Health University of São Paulo at Ribeirão Preto College of NursingRibeirão Preto 14040-902SPBrazil

BACKGROUND Colitis-associated cancer(CAC)accounts for 2%-3%of colorectal cancer(CRC)cases preceded by inflammatory bowel diseases(IBD)such as Crohn's disease and ulcerative *** microbiota has been reported to play a central role in the pathogenesis of IBD and ***,numerous prebiotics and probiotics have being investigated as antitumor agents due to their capacity to modulate inflammatory *** studies have indicated that lactic acid bacteria could be successfully used in managing sporadic CRC,however little is known about their role in *** To investigate the effect of the probiotic Lactobacillus bulgaricus(***)during the development of an experimental model of colitis associated colon cancer(CAC).METHODS C57BL/6 mice received an intraperitoneal injection of azoxymethane(10 mg/kg),followed by three cycles of sodium dextran sulphate diluted in water(5%w/v).Probiotic group received daily *** inflammation was determined by scoring clinical *** levels were determined from colon and/or tumor samples by ELISA BD OptEIATM *** level of significance was set at P<*** were generated and statistical analysis performed using the software GraphPad Prism *** *** treatment inhibited of total tumor volume and mean size of *** addition,the probiotic also attenuated the clinical signs of intestinal inflammation inducing a decrease in intestinal and tumor levels of IL-6,TNF-α,IL-17,IL-23 and IL-1β.CONCLUSION Our results suggest a potential chemopreventive effect of probiotic on *** regulates the inflammatory response and preventing CAC.

关键词： Lactobacillus bulgaricus Colitis-associated cancer Colorectal cancer Carcinogenesis Probiotics Inflammation

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Structure and genetic diversity of natural populations of Guadua weberbaueri in the southwestern Amazon,Brazil

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Journal of Forestry Research 2021年第2期32卷 755-763页

作者： Glória da silva Almeida Leal Fabrício Assis Leal Hugo Teixeira Gomes Anderson Marcos de Souza Sabina Cerruto Ribeiro Jonny Everson Scherwinski-pereira Centro Multidisciplinar Universidade Federal do AcreCruzeiro do SulAcreBrazil Universidade de Brasília BrasíliaDistrito FederalBrazil Centro de Ciências Biológicas e da Natureza Universidade Federal do AcreRio BrancoAcreBrazil Centro de Pesquisa e Aplicação de Bambu e Fibras Naturais Universidade de Brasília–CPAB/UnBBrasíliaDistrito FederalBrazil Embrapa Recursos Genéticos e Biotecnologia Av.W5 Norte(final)PqEBBrasíliaDistrito Federal 70770-917Brazil

The Brazilian state of Acre has an extensive natural reserve of bamboo,making it one of the largest in loco gene *** aim of this study was to characterize the structure and genetic diversity of Guadua weberbaueri *** two populations,one native(FAPB)and the other anthropized(FAPBA),using ISSR *** results show that the FAPB population exhibited higher values for all estimates of population ***,the FAPBA population also showed high heterozygosity,corroborated by estimated gene flow(Nm=3.9)between the *** study of the association between Nei’s genetic distances and the geographic distances between the populations were significantly correlated(r=0.45,p=0.01),corroborated by the dendrogram revealing two distinct groups corresponding to the collection sites,without mixing classes between populations in the same *** for the coancestry coefficient,pairs of individuals in the first distance class were positive and significant,indicating that plants that are geographically closer share common alleles with a frequency greater than by chance,which means that there is a tendency that geographically closer individuals are *** presented similar genetic structure when the geographical distance between them was up to 56 m for FAPB and up to 156 m for *** was concluded that anthropized environments exhibit less genetic diversity than native environments,inferring risks for species conservation if appropriate and planned management techniques are not adopted.

关键词： Guadua Bamboo Genetic diversity Amazon rainforest Anthropized and native populations Underutilization plants

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Antioxidant and antitumor potential of wild and IMT-Acultivated Osmundea pinnatifida

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Journal of Oceanology and Limnology 2019年第3期37卷 825-835页

作者： silva J.Paulo ALVES Celso PINTEUS Susete silva Joana VALADO Ana PEDROSA Rui pereira Leonel UCIBIO-REQUIMTE Department of ChemistryFaculty of Sciences and TechnologyUniversidade NOVA de LisboaCaparica 2829-516Portugal MARE-Marine and Environmental Sciences Centre School of Tourism and Maritime TechnologyPolytechnic Institute of LeiriaPeniche 2520-641Portugal Instituto Politécnico de Coimbra ESTESC-Coimbra Health SchoolBiomedical Sciences LaboratoryR.5 de OutubroS.Martinho do BispoAp.7006Coimbra 3046-854Portugal Centre of Pharmacology and Chemical Biopathology Faculty of MedicineUniversity of PortoPorto 4200-319Portugal MARE-Marine and Environmental Sciences Centre Department of Life SciencesFaculty of Sciences and TechnologyUniversity of CoimbraCoimbra 3000-456Portugal

Osmundea pinnatifida is a red edible seaweed known as pepper *** was cultivated in the farm of ALGAplus(ílhavo,Portugal).This farm is integrated with a seabream and seabass commercial aquaculture and uses the nutrient-enriched water resultant from the fish production as its cultivation medium in the integrated multi-trophic aquaculture(IMTA)*** and IMTA-cultivated samples of *** da were screened for antioxidant and antitumor *** antioxidant capacity of solvent extracts from wild and IMTA cultivated samples was assessed in two methods(2,2-diphenyl-1-picrylhydrazyl(DPPH)and oxygen radical absorbance capacity(ORAC)),and their total phenolic contents(TPC)were *** activity was evaluated in three different tumor cell lines(HepG-2,MCF-7,and SH-SY5Y)through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)*** the solvents used for extraction,dichloromethane was the most eff ective to extract phenolic compounds and presented higher ORAC.A significant correlation was found between TPC and ORAC,which was also sustained by the principal components analysis(PCA).Dichloromethane extracts induced a cytostatic eff ect on MCF-7 cells and showed weak cytotoxicity to SH-SY5Y cells and weak impact on cell ***,there were no statistically signifi cant differences in the biological activities shown by the wild and IMTA-cultivated ***,*** can be obtained in an economical and environmentally sustainable way through IMTA,maintaining bioactive properties in a high potential for further nutraceutical purposes.

关键词： edible seaweed bioactive compounds polyphenols cytotoxic activity antiproliferative activity

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高校图书馆信息共享空间利用率提升策略研究

教育教学研究前沿

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教育教学研究前沿 2024年第1期2卷 87-90页

作者：塔伊斯·达·席尔瓦·佩雷拉乔昂·维托尔·桑托斯·苏萨巴西伯南布哥大学孔子学院巴西累西腓50030

高校图书馆作为学术信息资源的重要承载机构,其信息共享空间的利用率对于提高学术资源的传播效率和服务质量具有重要意义。然而,在当前信息技术快速发展的背景下,图书馆信息共享空间的利用率仍存在影响其发展的一些因素亟待解决。如何... 详细信息

高校图书馆作为学术信息资源的重要承载机构,其信息共享空间的利用率对于提高学术资源的传播效率和服务质量具有重要意义。然而,在当前信息技术快速发展的背景下,图书馆信息共享空间的利用率仍存在影响其发展的一些因素亟待解决。如何提升高校图书馆信息共享空间利用率,帮助学生和教师更好地获取和利用学术资源,是值得高校管理人员深入探讨的重要课题。对此,本文首先阐述了影响高校图书馆信息共享空间利用率的因素,进而探究提升高校图书馆信息共享空间利用率的策略,以期为高校图书馆的发展提供有益的参考和借鉴。

关键词：高校图书馆共享空间

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Antibacterial enhancement of antibiotic activity by Enterolobium contortisiliquum(Vell.)Morong

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Asian Pacific Journal of Tropical Biomedicine 2017年第10期7卷 945-949页

作者： Zildene de Sousa Silveira Nair silva Macêdo Thiago Sampaio de Freitas Ana Raquel pereira da silva Joycy Francely Sampaio dos Santos Maria Flaviana Bezerra Morais-Braga José Galberto Martins da Costa Raimundo Nonato pereira Teixeira Jean Paul Kamdem Henrique Douglas Melo Coutinho Francisco Assis Bezerra da Cunha Laboratorio de Bioprospeccao do Semioarido Universidade Regional do CaririCratoBrazil Laboratorio de Microbiologia e Biologia Molecular Universidade Regional do CaririCratoBrazil Laboratorio de Pesquisas de Produtos Naturais Universidade Regional do CaririCratoBrazil Departamento de Ciencias biologicas Universidade Regional do Cariri-URCACratoCEP:63105-000Brazil Programa de Pos-graduacao em Bioprospeccao Molecular Universidade Regional do Cariri–URCACratoBrazil

Objective: To identify the main chemical classes of compounds from aqueous extract of Enterolobium contortisiliquum(E. contortisiliquum) seed bark and to evaluate its antibacterial activity, as well as its potential to increase the activity of antibiotics against strains of Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia ***: Different classes of compounds in the aqueous extract of E. contortisiliquum were evaluated based on the visual changes in the coloration and the formation of precipitate after the addition of specific reagents. The antibacterial activity of the extract and its potential to increase of antibiotic activity of antibiotics drugs, gentamicin and norfloxacin was determined by using the microdilution ***: Our results demonstrated that the following secondary metabolites were presented in E. contortisiliquum seed bark: flavones, flavonols, xanthones, flavononols,chalcones, aurones, flavones and catechins. The extract itself had very low antibacterial activity against all bacterial strains tested(MIC ≥ 1024 μg/m L), but there was an increase in the antibiotic activity of gentamicin and norfloxacin when combined in the subinhibitory concentration(i.e., MIC/8).Conclusions: Our data suggests that E. contortisiliquum seed bark may be an alternative source for new drugs with the potential to increase antibiotic activity against different strains of bacteria.

关键词： Antibiotic activity Enhancement Synergism Chemical compounds Bioactivity

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