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Tritrichomonas foetus:New structures by high-resolution scanning helium ion microscopy

BIOCELL 2021年第2期45卷 259-266页

作者： MARLENE BENCHIMOL ABIGAIL MIRANDA-MAGALHÃES antonio pereira-neves WANDERLEY DE SOUZA Universidade do Grande Rio Duque de Caxias25071-202Rio de Janeiro Departamento de Microbiologia Laboratório de Biologia Celular de PatógenosFiocruzInstituto Aggeu MagalhãesRecife52060-269Brazil Universidade Federal do Rio de Janeiro Instituto de Biofísica Carlos Chagas FilhoLaboratório de Ultraestrutura Celular Hertha Meyer Instituto Nacional de Ciência e Tecnologia(INBEB)and Centro Nacional de Biologia Estrutural e Bioimagens(CENABIO)Rio de Janeiro21941-902Brazil

Helium ion scanning microscopy(HIM)is a novel high-resolution scanning microscopy technique that uses helium ions instead of electrons to form images of the highest quality and resolution,providing a sub-nanometer resolution sputter uncoated biological ***,we took advantage of HIM to explore the cell surface of Tritrichomonas foetus,a protist parasite of cattle that provokes hard infection and abortion in *** describe thin protrusions,like nanotubes described in other cells,with different sizes(27 nm to 81 nm in thickness)and various lengths(from 73 nm to 2μm),as well bulbous structures either budding from the cell surface or present in the extremities of some *** flagella also presented these thin protrusions and different protein decoration,similar to those previously described using freeze-fracture *** between two cells were also seen,and their role in infection is *** cell surface was also examined and showed several pits indicative of endocytic activity and other types of arrays of *** observations were confirmed using Scanning Electron Microscopy(SEM),negative staining,and conventional thin sectioning for observation by transmission electron *** findings provide new and relevant information that may contribute to a better understanding of protozoan biology and its interaction with mammalian cells.

关键词： Nanotubes Microvesicles Surface specializations

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Therapeutic targeting of cellular prion protein: toward the development of dual mechanism anti-prion compounds

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Neural Regeneration Research 2025年第4期20卷 1009-1014页

作者： antonio Masone Chiara Zucchelli Enrico Caruso Giovanna Musco Roberto Chiesa Laboratory of Prion Neurobiology Department of NeuroscienceIstituto di Ricerche Farmacologiche Mario Negri IRCCSMilanItaly Biomolecular NMR Unit Division of Genetics and Cell BiologyIRCCS Ospedale San RaffaeleMilanItaly Department of Biotechnology and Life Sciences University of InsubriaVareseItaly

PrPSc,a misfolded,aggregation-prone isoform of the cellular prion protein(PrPC),is the infectious prion agent responsible for fatal neurodegenerative diseases of humans and other *** adopt different pathogenic conformations(prion strains),which can be resistant to potential drugs,or acquire drug resistance,posing challenges for the development of effective *** PrPCis the obligate precursor of any prion strain and serves as the mediator of prion neurotoxicity,it represents an attractive therapeutic target fo r prion *** this minireview,we briefly outline the approaches to target PrPCand discuss our recent identification of Zn(Ⅱ)-Bn PyP,a PrPC-targeting porphyrin with an unprecedented bimodal mechanism of *** argue that in-depth understanding of the molecular mechanism by which Zn(Ⅱ)-Bn PyP targets PrPCmay lead toward the development of a new class of dual mechanism anti-prion compounds.

关键词： anti-prion drug anti-PrPC antibody antisense oligonucleotide neurodegeneration pharmacological chaperone porphyrin prion disease PrPC degrader PrPC shedding zinc finger repressor

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Litter production and leaf nutrient concentration and remobilization in response to climate seasonality in the central Amazon

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Journal of Forestry Research 2024年第3期35卷 131-141页

作者： Ricardo antonio Marenco Saul Alfredo Antezana-Vera Daniela pereira Dias Luiz antonio Candido Instituto Nacional de Pesquisas da Amazonia Coordenagao de Uso da Terra e Mudanca ClimaticaAv.Andre Araujo 2936ManausAM69067-375Brazil Programa de pos-Graduagao em Agricultura no Tropico Umido Instituto Nacional de Pesquisas da Amazonia-INPAManausAMBrazil Unidade Academica de Ciencias Agrarias Universidade Federal de JataiBR 364km 195JataiGO 75801-615Brazil

Litterfall is the largest source of nutrients to for-est soils of tropical ***,variability in lit-terfall production,nutrient remobilization,and changes in leaf nutrient concentration with climate seasonality remain largely unknown for the central *** study meas-ured litterfall production,leaf nutrient remobilization,and leaf area index on a forest plateau in the central *** was measured at monthly intervals during 2014,while nitrogen,phosphorus,potassium,calcium and mag-nesium concentrations of leaf litter and canopy leaves were measured in the dry and rainy seasons,and remobilization rates *** area index was also recorded in the dry and rainy *** litterfall varied from 33.2(in the rainy season)to 87.6 g m^(-2) in the dry season,while leaf area index increased slightly in the rainy *** seasonality had no effect on concentrations of nitrogen,calcium,and magnesium,whereas phosphorous and potassium responded to rainfall seasonality *** phosphorous increased,potassium decreased during the dry *** seasons,nitrogen,potassium,and phosphorous decreased in leaf litter;calcium increased in leaf litter,while magnesium remained unaffected with leaf ***,the five nutrients had similar remobilization rates over the *** absence of climate seasonality on nutrient remobilization suggests that the current length of the dry season does not alter nutrient remobilization rates but this may change as dry periods become more prolonged in the future due to climate change.

关键词： Throughfall Nutrient cycling Climatic seasonality Leaf mass per area

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Endoscopic techniques for the diagnosis of pancreatic cystic lesions

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World Journal of Gastroenterology 2025年第1期31卷 1-7页

作者： Sahib Singh Saurabh Chandan Rakesh Vinayek Jahnvi Dhar Jayanta Samanta Gabriele Capurso Ivo Boskoski Cristiano Spada Jorge D Machicado Stefano Francesco Crinò antonio Facciorusso Department of Internal Medicine Sinai HospitalBaltimoreMD 21215United States Division of Gastroenterology and Hepatology Creighton University School of MedicineOmahaNE 68131United States Department of Gastroenterology Sinai Hospital of BaltimoreBaltimoreMD 21215United States Department of Gastroenterology Postgraduate Institute of Medical Education and ResearchChandigarh 160012India Division of Pancreato-Biliary Endoscopy and Endosonography Pancreas Translational and Clinical Research CenterIRCCS San Raffaele Scientific InstituteVita-Salute San Raffaele UniversityMilano 20132Italy Digestive Endoscopy Unit Fondazione Policlinico Universitario Agostino Gemelli IRCSSUniversitàCattolica del Sacro Cuore di RomaCenter for Endoscopic Research Therapeutics and TrainingRoma 00168Italy Department of Gastroenterology and Endoscopy Catholic UniversityRoma 00168Italy Department of Gastroenterology University of Michigan HealthAnn ArborMI 48107United States Department of Endoscopy University of VeronaVerona 37121VenetoItaly Gastroenterology Unit Department of Medical and Surgical SciencesUniversity of FoggiaFoggia 71122Italy

Pancreatic cysts are mostly incidental findings on computed tomography or magnetic resonance imaging scans,with few patients presenting with abdominal pain or other *** accurate diagnosis of cysts is important as management depends on the type(neoplastic or non-neoplastic).Cross-sectional imaging is fast being replaced with endoscopic ultrasound(EUS)and various techniques based on that such as EUS-guided fine needle aspiration,EUS-guided needle confocal laser endomicroscopy,EUS-through-the-needle biopsy,and contrast-enhanced *** studies have reported varying diagnostic and adverse event rates with these *** addition,American,European,and Kyoto guidelines for the diagnosis and management of pancreatic cysts have provided different *** this editorial,we elaborate on the clinical guidelines,recent studies,and comparison of different endoscopic methods for the diagnosis of pancreatic cysts.

关键词： Endoscopic ultrasound Fine needle aspiration Needle confocal laser endomicroscopy Through-the-needle biopsy Contrast-enhanced endoscopic ultrasound

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Methylation changes at the GNAS imprinted locus in pancreatic cystic neoplasms are important for the diagnosis of malignant cysts

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World Journal of Gastrointestinal Oncology 2020年第9期12卷 1056-1064页

作者： Sandra Faias Marlene Duarte Luísa pereira Paula Chaves Marília Cravo antonio Dias pereira Cristina Albuquerque Department of Gastroenterology Instituto Português de Oncologia de Lisboa Francisco GentilEPELisboa 1099-023Portugal Faculty of Health Sciences University of Beira InteriorCovilhã6200-506Portugal Unidade de Investigação em Patobiologia Molecular(UIPM) Instituto Português de Oncologia de Lisboa Francisco GentilEPELisboa 1099-023Portugal Centro de Matemática e Aplicações(CMA-UBI) Universidade da Beira InteriorCovilhã6200-506Portugal Department of Pathology Instituto Português de Oncologia de Lisboa Francisco GentilEPELisboa 1099-023Portugal Department of Gastroenterology Hospital BeatrizÂngeloLoures 2674-514Portugal

BACKGROUND Guanine nucleotide-binding protein,alpha stimulating(GNAS)mutations are characteristic of intraductal papillary mucinous neoplasms(IPMNs).Pancreatic ductal adenocarcinomas(PDACs)harboring GNAS mutations originate in *** is a complex imprinted locus that produces five transcripts regulated by differential methylated regions,NESP55,GNASAS,GNASXL,GNAS1A,and *** To evaluate if methylation changes in the differential methylated regions of GNAS locus contributed to malignant progression of pancreatic *** GNAS locus methylation was analyzed in archival pancreatic cyst fluid(PCF)obtained by endoscopic ultrasound with fine-needle aspiration by methylation specific–multiplex ligation dependent probe *** were normalized and analyzed using *** *** Fifty-two PCF samples obtained by endoscopic ultrasound with fine-needle aspiration and previously characterized for KRAS and GNAS mutations were *** final diagnoses were surgical(11)and clinicopathological(41),including 30 benign cysts,14 pre-malignant cyst,and eight malignant *** changes at NESP55,GNASAS,GNAS1A,and especially GNASXL were more frequent in malignant cysts,and NESP55 and GNASAS were useful for diagnosis.A combined variable defined as“GNAS locus methylation changes”was significantly associated with malignancy(6/8 malignant cysts and only 2/20 benign cysts)and improved *** in both maternally(NESP55)and paternally(GNASXL)derived promoters was found in 3/3 *** This is the first study to identify methylation changes in the GNAS locus,improving the diagnosis of malignant pancreatic cysts and suggesting a role in progression to PDAC.

关键词： Intraductal papillary mucinous neoplasms Pancreas cyst Methylation Biomarker GNAS locus Pancreatic neoplasm

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Pulp and Paper from Sugarcane:Properties of Rind and Core Fractions

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Journal of Renewable Materials 2018年第2期6卷 160-168页

作者： Lísias pereira Novo Julien Bras Mohamed Naceur Belgacem antonio Aprigio da Silva Curvelo Department of Materials Engineering Sao Carlos School of EngineeringUniversity of Sao PauloAv.Joao Dagnone 110013563-120Sao CarlosSao PauloBrazil Department of Physical Chemistry Sao Carlos Institute of ChemistryUniversity of Sao PauloAv.Trabalhador Sao Carlense 40013560-970Sao CarlosSao PauloBrazil Grenoble Alpes University LGP2F-38000 GrenobleFrance CNRS LGP2F-38000 GrenobleFrance

Two distinct lignocellulosic fractions(rind and core)can be obtained through a physical separation of sugarcane *** presenting differences in morphology,both fractions can be employed to produce pulps and *** pulps and paper sheets produced from the core and rind fractions were characterized by their chemical composition,physical properties and mechanical *** pulps obtained from the core presented a higher amount of fines,lower drainage ability and rendered denser and stiffer *** pulps from the rind,which have a higher content of fibers and higher degree of polymerization,produced sheets with higher air permeability and water *** paper sheets presented mechanical and physical properties comparable to commercial papers and papers from different cellulosic *** different properties exhibited by the papers produced from each fraction allow their use for distinct purposes,and expands the opportunities in the context of sugarcane biorefinery.

关键词： Sugarcane core and rind fractions papermaking pulp and paper

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Therapeutic and prophylactic thalidomide in TNBS-induced colitis: Synergistic effects on TNF-α, IL-12 and VEGF production

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World Journal of Gastroenterology 2007年第15期13卷 2166-2173页

作者： Ana Teresa Carvalho Heitor Souza antonio Jose Carneiro Morgana Castelo-Branco Kalil Madi Alberto Schanaider Flavia Silva Fernando antonio pereira Júnior Márcia G pereira Cláudio Tortori Ilana Dines Jane Carvalho Eduardo Rocha Celeste Elia Departamento de Clínica Médica Hospital Universitário Clementino Fraga Filho Brazil Departamento de Histologia e Embriologia Laboratório de Imunologia Celular Instituto de Ci(e|^)ncias BiomédicasUniversidade Federal do Rio de Janeiro21941-590Brazil Laboratório Multidisciplinar de Pesquisa Anatomia Patológica Hospital Universitário Clementino Fraga FilhoBrazil e Cirurgia Experimental Hospital Universitário Clementino Fraga Filho Brazil

AIM： To evaluated the therapeutic and prophylactic effect of thalidomide on 2, 4, 6-trinitrobenzene sulfonic acid （TNBS）-induced colitis. Thalidomide has been reported to downregulate the expression of tumor necrosis factor α （TNF-α）, IL-12, and vascular endothelial growth factor （VEGF）, hallmarks of intestinal inflammation in Crohn＇s disease （CD）. METHODS： Male Wistar rats were divided in five groups of ten animals each. Four groups received a rectal infusion of TNBS in ethanol. The first group was sacrificed 7 d after colitis induction. The second and third groups received either thalidomide or placebo by gavage and were sacrificed at 14 d. The fourth group received thalidomide 6 h before TNBS administration, and was sacrificed 7 d after induction. The fifth group acted as the control group and colitis was not induced. Histological inflammatory scores of the colon were performed and lamina propria CD4＋ T cells, macrophages, and VEGF＋ cells were detected by immunohistochemistry. TNF-α and IL-12 were quantified in the supernatant of organ cultures by ELISA. RESULTS： Significant reduction in the inflammatory score and in the percentage of VEGF＋ cells was observed in the group treated with thalidomide compared with animals not treated with thalidomide. Both TNF-α and IL-12 levels were significantly reduced among TNBS induced colitis animals treated with thalidomide compared with animals that did not receive thalidomide. TNF-α levels were also significantly reduced among the animals receiving thalidomide prophylaxis compared with untreated animals with TNBS-induced colitis. Intestinal levels of TNF-α and IL-12 were significantly correlated with the inflammatory score and the number of VEGF＋ cells. CONCLUSION： Thalidomide significantly attenuates TNBS-induced colitis by inhibiting the intestinal production of TNF-α, IL-12, and VEGF. This effect may support the use of thalidomide as an alternate approach in selected patients with CD.

关键词： Thalidomide Experimental colitis Inflammatory bowel disease Tumor necrosis factor α IL-12 Vascular endothelial growth factor

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New beverage based on grapes and purple-fleshed sweet potatoes:Use of non-standard tubers

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Food Bioscience 2022年第3期47卷 279-288页

作者： Letícia Silva pereira Basílio Cristine Vanz Borges Igor Otavio Minatel Pablo Forlan Vargas Marco antonio Tecchio Fabio Vianello Giuseppina Pace pereira Lima Department of Chemical and Biological Sciences Institute of BiosciencesSão Paulo State University18.618-000 BotucatuSão PauloBrazil Tropical Root and Starches Center São Paulo State University18610-034 BotucatuSão PauloBrazil Department of Crop Production School of AgricultureSão Paulo State University18.610-034 BotucatuSão PauloBrazil Department of Comparative Biomedicine and Food Science University of Padova35020LegnaroItaly

Grapes and sweet potatoes are two different plant species that have distinct bioactive composition and the use of both in a non-alcoholic mixed beverage may be an interesting source of *** and sensory characteristics,profile of phenolic compounds and biogenic amines of mixed juices of grapes (‘BRS Violeta’,‘BRS Cora’ and ‘Bordô’) and purple-fleshed sweet potato (‘JNRX12’) (0,10 and 30%) were *** beverage with sweet potato had high antioxidant activity attributed to the phytochemical compounds (***,gallic acid,catechin,tryptophan,melatonin,serotonin and dopamine).Low levels of unwanted amines (histamine,tyramine,putrescine and cadaverine) were detected,showing that their consumption is ***-fleshed sweet potato had high levels of desirable amines,mainly melatonin,making the addition of sweet potato attractive for enriching *** color,texture and sensory aspects were similar in whole grape juice and in mixed *** from ‘BRS Violeta’,with or without sweet potato showed high levels of bioactive compounds but were the least *** overall appearance and aroma of juices elaborated from ‘BRS Cora’ or ‘Bordô' grapes had similar acceptance,regardless of the addition of sweet *** from ‘BRS Cora’ and 30% purple-fleshed sweet potato are the most interesting mixture due to tryptophan and melatonin *** juices of grapes and sweet potatoes (10% and 30%) are viable options for the use of tubers outside the commercial standard,as they add interesting bioactive compounds to beverages and please the consumer.

关键词： Functional beverages Phenolic compounds Biogenic amines Quality index

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Mechanisms of neuroplasticity and brain degeneration: strategies for protection during the aging process

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Neural Regeneration Research 2021年第1期16卷 58-67页

作者： Mariana Toricelli Arthur antonio Ruiz pereira Guilherme Souza Abrao Helena Nascimento Malerba Julia Maia Hudson Sousa Buck Tania Araujo Viel Department of Physiological Sciences Santa Casa de Sao Paulo School of Medical SciencesSao PauloBrazil Laboratory of Neurobiology of Aging School of ArtsSciences and HumanitiesUniversidade de São PauloSao PauloBrazil

Aging is a dynamic and progressive process that begins at conception and continues until *** process leads to a decrease in homeostasis and morphological,biochemical and psychological changes,increasing the individual’s vulnerability to various *** growth in the number of aging populations has increased the prevalence of chronic degenerative diseases,impairment of the central nervous system and dementias,such as Alzheimer’s disease,whose main risk factor is age,leading to an increase of the number of individuals who need daily support for life *** theories about aging suggest it is caused by an increase of cellular senescence and reactive oxygen species,which leads to inflammation,oxidation,cell membrane damage and consequently neuronal ***,mitochondrial mutations,which are generated throughout the aging process,can lead to changes in energy production,deficiencies in electron transport and apoptosis induction that can result in decreased ***,increasing cellular senescence and the release of proinflammatory cytokines can cause irreversible damage to neuronal *** reports point to the importance of changing lifestyle by increasing physical exercise,improving nutrition and environmental enrichment to activate neuroprotective defense ***,this review aims to address the latest information about the different mechanisms related to neuroplasticity and neuronal death and to provide strategies that can improve neuroprotection and decrease the neurodegeneration caused by aging and environmental stressors.

关键词： cell senescence cell signaling cholinergic enriched environment long-term potentiation neurodegeneration neurogenesis neuroinflammatory neuronal death neuroprotection neurotophin

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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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