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Tailoring the partitioning of proteins using ionic liquids as adjuvants in polymer-polymer aqueous biphasic systems

Green Chemical Engineering 2022年第4期3卷 328-337页

作者： flavia f.magalhaes Matheus M.Pereira Rita de Cassia Superbi de Sousa Ana P.M.Tavares Joao A.P.Coutinho Mara G.freire CICECO-Aveiro Institute of Materials Department of ChemistryUniversity of AveiroAveiro3810-193Portugal Separation Process Laboratory(LPS) Department of Food TechnologyFederal University of Viçosa(UFV)P.H.Rolfs Av.s/n36570-000 ViçosaMGBrazil

Aqueous biphasic systems(ABS)are promising for proteins purification;however,when dealing with samples comprising several proteins,the selectivity towards a target protein is difficult to *** this work,the addition of ionic liquids(ILs)as adjuvants(5 wt%and 10 wt%)in ABS composed of polyethylene glycol(PEG)and dextran was investigated to tailor proteins partitioning between the coexisting *** liquid-liquid phase diagrams were determined at 298 K,followed by partition studies of three proteins(bovine serum albumin(BSA),immunoglobulin G(IgG),and cytochrome C(Cyt C)).Partition coefficients of IgG and BSA indicate the preference of both proteins to the dextran-rich phase,whereas Cyt C has no preferential partitioning between the *** addition of chloride-based ILs as adjuvants allows to increase or decrease the partition coefficients,thus tailoring the proteins partitioning between the *** partitioning essentially depends on the IL content in each phase,whereas Cyt C and IgG partitioning is ruled by the ILs chemical structure and established *** docking was carried out to address the ILs effect on the proteins partitioning,supporting experimental observations,while identifying the specific interactions *** partition of each protein in polymer-salt ABS with ILs as adjuvants was determined,demonstrating the higher tailoring ability of polymer-polymer ABS when adding ***,the partition of each protein in presence of the remaining ones was determined,as well as the selectivity of the studied systems to separate each pair of proteins,paving the way for their use in liquidliquid chromatography.

关键词： Aqueous biphasic systems Polymer-polymer systems Protein partition Ionic liquids Adjuvants

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Genetic diversity and population structure of Prochilodus costatus and Prochilodus argenteus preceding dam construction in the Paraopeba River,Sao francisco River Basin,Minas Gerais,Brazil

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Open Journal of Genetics 2012年第2期2卷 121-130页

作者： Tatiana M.Barroca fabio P.Arantes Barbara f.magalhaes flavia f.Siqueira Carolina C.R.Horta Isabella f.Pena Jorge A.Dergam Evanguedes Kalapothakis Departamento de Biologia Geral Instituto de Ciencias BiologicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil Programa de Pos-Graduacao em Zoologia de Vertebrados Pontificia Universidade Catolica de Minas GeraisBelo HorizonteBrazil Departamento de Biologia Animal Centro de Ciencias Biologicas e da SaudeUniversidade Federal de VicosaVicosaBrazil

Curimat?-pioa (Prochilodus costatus) and curimat?-pacu (Prochilodus argenteus) are migratory fish species endemic to the S?o francisco River Basin in Brazil. Both species play important roles in local fisheries and ecology in the Paraopeba River. A dam was recently constructed on this river and to help in the development and conservation programs, we characterized the genetic variation of both species before dam construction. Complex hypervariable repeats micro-satellite was used to asses genetic variation for both species within and between the five collection sites in order to detect population substructuring. Nucleotide substitutions and insertion/deletion polymorphisms (indels) resulted in 35 P. costatus haplotypes (sample size = 89) and 22 P. argenteus haplotypes (sample size = 32). Significant genetic diversity and population differentiation was detected between five sampling sites for both species. Therefore, each of the five sites should be regarded as a group comprising significant genetic differences in species conservation and maintenance plans. Comparing these results to genetic diversity measures after dam construction will be critical for future management in this region.

关键词： freshwater fish Complex Hypervariable Repeats Microsatellite Genetic Diversity Population Structure

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Vitamin B12-induced spermatogenesis recovery in cimetidine-treated rats： effect on the spermatogonia number and sperm concentration

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Asian Journal of Andrology 2017年第5期19卷 567-572页

作者： flavia L Beltrame Estela Sasso-Cerri Department of Morphology and Genetics Federal University of Sao Paulo (UNIFESP/EPM) Sao Paulo Brazil Department of Morphology Laboratory f Histology and Embryology Dental School - Sao Paulo State University (UNESP/FOAr) Araraquara Sao Paulo Brazil

The H2-receptor antagonist cimetidine is an antiulcer drug also used for the treatment of cancer due to its antiangiogenic effect. However, this drug has caused structural changes in the seminiferous tubules. Vitamin B12 has been used as a therapeutic agent for the treatment of male infertility. The supplementation of rats with vitamin B12 during cimetidine treatment has recovered the damaged seminiferous tubules, but how this vitamin restores the seminiferous epithelium has not been clarified. In this study, we evaluated whether vitamin B12 improves the number of spermatogonia, spermatocytes, and sperm concentration in cimetidine-treated rats. Adult male rats were treated for 50 days as follows： cimetidine group received 100 mg kg^-1 b.w. of cimetidine, cimetidine-B12 group received cimetidine and 3 μg of vitamin B12-hydroxocobalamin, B12 group received only 3 μg of vitamin, and control group received saline. Sperm concentration was calculated and historesin-embedded testes sections were used for the quantitative analyses of spermatogonia （A; In/B） and spermatocytes. TUNEL method and PCNA immunofluorescence were performed. Cimetidine caused a significant reduction in sperm concentration. TUNEL-positive spermatogonia and spermatocytes were correlated to a significant reduction in the number of these cells. In cimetidine-B12 group, sperm concentration was higher than cimetidine group and a significant increase in the number of spermatogonia （stages Ⅱ-Ⅵ） was correlated to a high incidence of PCNA-immunolabeled spermatogonia and spermatocytes. The results show that the supplementation of rats with vitamin B12 during cimetidine treatment increases sperm concentration and exerts a potential effect in the recovery of spermatogonia and spermatocytes.

关键词： cimetidine fertility spermatogenesis testis vitamin B12

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Consequences of Helicobacter pylori infection in children

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World Journal of Gastroenterology 2010年第41期16卷 5181-5194页

作者： Lucia Pacifico Caterina Anania John f Osborn flavia ferraro Claudio Chiesa Department of Pediatrics Sapienza University of Rome 324 I-00161 Rome Italy Department of Public Health Sciences Sapienza University of Rome I-00185 Rome Italy Department of Molecular Medicine National Research Council I-00133 Rome Italy

Although evidence is emerging that the prevalence of Helicobacter pylori (H. pylori) is declining in all age groups, the understanding of its disease spectrum continues to evolve. If untreated, H. pylori infection is lifelong. Although H. pylori typically colonizes the hu-man stomach for many decades without adverse con-sequences, children infected with H. pylori can manifest gastrointestinal diseases. Controversy persists regarding testing (and treating) for H. pylori infection in children with recurrent abdominal pain, chronic idiopathic thrombocytopenia, and poor growth. There is evidence of the role of H. pylori in childhood iron deficiency anemia, but the results are not conclusive. The possibility of an inverse relationship between H. pylori and gastroesophageal reflux disease, as well as childhood asthma, remains a controversial question. A better understanding of the H. pylori disease spectrum in childhood should lead to clearer recommendations about testing for and treating H. pylori infection in children who are more likely to develop clinical sequelae.

关键词： Helicobacter pylori Children Gastrointestinal diseases Epigastric pain Anemia Growth retardation Chronic idiopathic thrombocytopenic pupura

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Relaxant effect and possible mechanism of 17-nor-subincanadine E in rabbit corpora cavernosa

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Asian Journal of Andrology 2011年第5期13卷 747-753页

作者： Otacilio D Benvindo Nilberto Rf Nascimento Claudia f Santos Manasses C fonteles Edilberto R Silveira Daniel E Uchoa Adriana R Campos Karina MA Cunha flavia A Santos Vietla S Rao Department of Physiology and Pharmacology Faculty of Medicine Federal University of Ceara PO Box 3157 60430-270 Fortaleza CE Brazil Superior Institute of Biomedicine Caara State University Fortaleza CE Brazil Detriment of Organic and Inorganic Chemistry Federal University of Ceara 60455-760 Fortaleza CE Brazil

Compounds with dual action on cyclic adenosine monophosphate （cAMP） and cyclic guanosine monophosphate （cGMP） may be a treatment option for erectile dysfunction, as they not only promote penile erection but also prevent the upregulation of phosphodiesterase-5. In this study, we examined the possible relaxant effect and mechanism of 17-nor-subincanadine E （SEC, 0.2-200 pmol I^-1）, a plant-derived alkaloid, in rabbit corpus cavernosum （RbCC） strips that had been precontracted by exposure to phenylephrine （10 pmol I^- 1） or a high concentration of K＋（60 mmol I^- 1） in vitro. In addition to SEC＇s effect on cAMP and cGMP levels, electrical field stimulation （EfS） in phenylephrine-precontracted RbCC and calcium chloride （1-100 mmol I^-1） evoked responses in depolarized RbCC were analysed. SEC relaxed the phenylephrine-precontracted RbCCs in a concentration-dependent manner. Atropine, guanethidine and N-co-nitro-L-arginine methyl ester （L-NAME） did not have any effect on the relaxation of RBCCs. When 1H-1,2,4oxadiazole[4,3-a] quinoxalin-1-one （ODQ） was added, it effectively blocked the relaxant response of SEC. Although SEC enhanced the maximal relaxation produced by sodium nitroprusside （SNP） and forskolin in phenylephrine-precontracted cavernosal smooth muscle, it caused a decrease in the maximal contractile response induced by calcium chloride in depolarized RbCCs. The relaxant effect of SEC was paralleled by an increase in the tissue levels of the Cyclic nucleotides cAMP and cGMP. We conclude that SEC promotes the relaxation of RbCC, possibly favouring cAMP and cGMP accumulation and calcium blockade. This novel mechanism could be useful for patients who do not benefit from phosphodiesterase inhibitors and for those with endothelial and nitrergic dysfunction, such as patients with diabetes, hypertension and dyslipidaemias.

关键词： 17-nor-subincanadine E cyclic nucleotides electrical field stimulation nitric oxide rabbit corpus cavernosum smoothmuscle relaxation

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Total Knee Arthroplasty:Patellar Replacement’s Influence in Patient Quality of Life Postoperatively

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Open Journal of Orthopedics 2017年第8期7卷 228-234页

作者： Carlos Roberto Schwartsmann Gabriel Severo da Silva Ivan fadanelli Simionato flavia magalhaes Nunes Henrique Lammerhirt Joao Pedro farina Brunelli Leandro de freitas Spinelli federal University of Medical Sciences Porto AlegreBrazil Department of Orthopedics and Traumatology Irmandade Santa Casa de Misericordia de Porto AlegrePorto AlegreBrazil

Objective: To study the influence of patellar resurfacing on quality of life under a standardised score. The chosen score was the Knee Society Score (KSS), which considers range of motion, pain, contractors, alignment and stability. Methods: Retrospective review of 60 patients submitted to total knee arthroplasty (TKA) was divided into two groups: with patellar resurfacing (PR) and without patellar resurfacing (NPR). We reviewed data from these patients containing the KSS, which are routinely used in our service. Data were analysed from 2013 to 2014, with a minimal patient follow-up of 18 months. Results: There were no unsatisfactory scores in our study. Total scores (KSS) were similar between the groups (mean KSS: PR = 88.36 ± 9.64;NPR = 84.26 ± 9.44 [p = 0.1]). While stratifying into groups (poor, fair, good, excellent), we found excellent results in 84.8% of PR versus 59.3% NPR (p = 0.056). These data did not reach statistical significance and can therefore be considered a coincidental result. Conclusion: Although these results did not show statistical significance (p = 0.056), patellar resurfacing patients tend to get more “excellent” results after 18 months of follow-up in quality of life when evaluated by KSS. Perhaps a larger amount of patients would suffice to acquire statistical significance in a future study.

关键词： Knee Arthroplasty Patella Joint Instability Quality of Life

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Modelling dynamic pantograph loads with combined numerical analysis

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Railway Engineering Science 2024年第1期32卷 81-94页

作者： f.f.Jackson R.Mishra J.M.Rebelo J.Santos P.Antunes J.Pombo H.magalhaes L.Wills M.Askill School of Computing and Engineering University of HuddersfieldHuddersfieldUK School of Computing and Engineering Institute of Railway ResearchUniversity of HuddersfieldHuddersfieldUK IDMEC Instituto Superior TecnicoUniversidade de LisboaLisbonPortugal ISEL Instituto Politecnico de LisboaLisbonPortugal Hitachi Rail Newton AycliffeUK Wabtec/Brecknell Willis ChardUK

Appropriate interaction between pantograph and catenary is imperative for smooth operation of electric *** heights of overhead lines to accommodate level crossings,overbridges,and tunnels pose significant challenges in maintaining consistent current collection performance as the pantograph aerodynamic profile,and thus aerodynamic load changes significantly with operational *** research aims to analyse the global flow characteristics and aerodynamic forces acting on individual components of an HSX pantograph operating in different configurations and orientations,such that the results can be combined with multibody simulations to obtain accurate dynamic insight into contact ***,computational fluid dynamics simulations are used to investigate the pantograph component loads in a representative setting,such as that of the recessed cavity on a Class 800 *** an aerodynamic perspective,this study indicates that the total drag force acting on non-fixed components of the pantograph is larger for the knuckle-leading orientation rather than the knuckle-trailing,although the difference between the two is found to reduce with increasing pantograph *** the aerodynamic loads acting on individual components with multibody tools allows for realistic dynamic insight into the pantograph *** results obtained show how considering aerodynamic forces enhance the realism of the models,leading to behaviour of the pantograph-catenary contact forces closely matching that seen in experimental tests.

关键词： Pantograph-catenary interaction Pantograph aerodynamics Computational fluid dynamics Pantograph loads Current collection performance

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Why Sustainable Porous Carbon Should be further Explored as Radar-Absorbing Material? A Comparative Study with Different Nanostructured Carbons

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Journal of Renewable Materials 2024年第10期12卷 1639-1659页

作者： Alan f.N.Boss Manuella G.C.Munhoz Gisele Amaral-Labat Rodrigo G.A.Lima Leonardo I.Medeiros Nila C.f.L.Medeiros Beatriz C.S.fonseca flavia L.Braghiroli Guilherme f.B.Lenz e Silva Department of Metallurgical and Materials Engineering University of de São PauloAvenida Mello MoraesCidade UniversitáriaSão PauloSP 05508-030Brazil Coordination of Applied Research and Technological Development National Institute for Space ResearchAvenida dos AstronautasJardim da GranjaSão Josédos CamposSP 12227-010Brazil Department of Exact and Technological Sciences Santa Cruz State UniversityRodovia Jorge Amadokm16IlhéusBA 45662900Brazil Institut de recherche sur les forêts Universitédu Québec en Abitibi-TémiscamingueRouyn-Noranda445 Bd de l’UniversitéRouyn-NorandaQC J9X 5E4Canada

Radar Absorbing Materials(RAM)are a class of composites that can attenuate incident electromagnetic waves to avoid radar *** carbon allotropes that have the potential to be used as RAM are either carbon nano-tubes(CNTs),graphene,carbon black(CB)and ultimately,sustainable porous carbon(SPC).Here,black wattle bark waste(following tannin extraction)was used as a sustainable source to produce SPC made from biomass *** was characterized and used as afiller for a silicone rubber matrix to produce aflexible *** elec-tromagnetic performance of this composite was compared with composites made with commercial CB and CNT through reflection loss(RL),where-10 dB is equivalent to 90%of *** composites were evaluated in single-layer,double-layer,and as radar absorbing structures(RAS)with the aim of improving their effective absorption bandwidth(EAB)performances and a reduction in *** CNT composite presented a RL of-26.85 dB at 10.89 GHz and an EAB of 2.6 GHz with a 1.9 mm thickness,while the double-layer structures using CNT and SPC provided a RL of-19.74 dB at 10.75 GHz and an EAB of 2.51 ***,the double-layer structures are~42%cheaper than the composite using only CNT since less material is ***,the largest EAB was achieved with a RAS using SPC,reaching~2.8 GHz and a RL of-49.09 dB at 10.4 ***,SPC made of black wattle bark waste can be a competitive,alternative material for use as RAM and RAS since it is cheaper,sustainable,and suitable for daily life uses such as absorbers for anechoic chambers,sensors,and elec-tromagnetic interference shields for electronics,wallets,vehicles,and others.

关键词： Microwave absorption material tannin waste dielectric constant carbon composite reflectivity

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Prospects for sociogenomics in avian cooperative breeding and parental care

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Current Zoology 2020年第3期66卷 293-306页

作者： flavia TERMIGNONI-GARCIA Matthew I.M.LOUDER Christopher N.BALAKRISHNAN Lauren O’CONNELL Scott V.EDWARDS Department of Organismic and Evolutionary Biology Harvard UniversityCambridgeMA 02138USA Museum of Comparative Zoology Harvard UniversityCambridgeMA 02138USA International Research Center for Neurointelligence The University of TokyoHongoBunkyo-kuTokyo 113-0033Japan Department of Biology East Carolina UniversityGreenvilleNC 27858USA Department of Biology Stanford UniversityStanfordCA 94305USA

for the last 40 years,the study of cooperative breeding(CB)in birds has proceeded primarily in the context of discovering the ecological,geographical,and behavioral drivers of *** advent of molecular tools in the early 1990s assisted in clarifying the relatedness of helpers to those helped,in some cases,confirming predictions of kin selection *** for genome-wide analysis of sequence variation,gene expression,and epigenetics promise to add new dimensions to our understanding of avian CB,primarily in the area of molecular and developmental correlates of delayed breeding and dispersal,as well as the ontogeny of achieving parental status in ***,we outline key ways in which modern-omics approaches,in particular genome sequencing,transcriptomics,and epigenetic profiling such as ATAC-seq,can be used to add a new level of ana-lysis of avian *** on recent and ongoing studies of avian social behavior and sociogenom-ics,we review how high-throughput sequencing of a focal species or clade can provide a robust foundation for downstream,context-dependent destructive and non-destructive sampling of spe-cific tissues or physiological states in the field for analysis of gene expression and epigenetics.-Omics approaches have the potential to inform not only studies of the diversification of CB over evolutionary time,but real-time analyses of behavioral interactions in the field or *** of birds represents a new branch in the network of methods used to study CB,and can help clarify ways in which the different levels of analysis of CB ultimately interact in novel and unexpected ways.

关键词： ATAC-seq behavior convergent evolution epigenetics neurobiology phylogeny

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Morphology and Thermal Properties of Core-Shell PVA/PLA Ultrafine fibers Produced by Coaxial Electrospinning

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Materials Sciences and Applications 2015年第2期6卷 189-199页

作者： Raquel P.Goncalves flavia f.f.da Silva Paulo H.S.Picciani Marcos L.Dias Institute of Macromolecules Federal University of Rio de JaneiroRio de JaneiroBrazil

Coaxial electrospinning process was used to produce biodegradable membranes made of coreshell fibers of a poly(lactic acid) (PLA) shell and a poly(vinyl alcohol) (PVA) core. Scanning electron microscopy analyses of these structures showed that the PLA shell can present certain porosity depending on the process condition. fTIR-ATR and contact angle measurements also suggested imprisonment of the PVA core within the PLA shell. This type of structure was also confirmed by means of transmissions electron microscopy. The morphology of these fibers was dependent on the flow rate of both core and shell solutions, and homogeneous and smooth surface was only attained when the flow rate of the external PLA solution was 4 times the flow rate of the internal PVA solution. The increase in the PLA solution flow rate increases the diameter of the core-shell fiber which reaches up to 1.7 μm. Nevertheless, fibers with smaller average diameter could also be produced (200 nm). These core-shell fibers presented improved hydrophilicity as compared with monolithic PLA fibers.

关键词： Core-Shell fibers Electrospinning Poly(Lactic Acid) Poly(Vinyl Alcohol)

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