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Selective silencing of 2Cys and type-ⅡB Peroxiredoxins discloses their roles in cell redox state and stress signaling

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Journal of Integrative Plant Biology 2015年第6期57卷 591-601页

作者： Patrícia Vidigal ana Montserrat Martin-Hernandez Cèlia Guiu-Aragonés Sara amncio Luísa carvalho departamento de Recursos Naturais Ambiente e Território (DRAT)/Centro de Botanica Aplicada à Agricultura (CBAA)Institute of AgronomyUniversity of Lisbon Institut de Recercai Tecnologia Agroalimentàries (IRTA) Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB) Campus Universitat Autonoma de Barcelona (UAB)Edificio Center for Research in Agricultural Genomics (CRAG)

Peroxiredoxins （Prx） catalyse the reduction of hydrogen peroxide （H2O2） and, in association with catalases and other peroxidases, may participate in signal transduction by regulating intercel ular H2O2 concentration that in turn can control gene transcription and cel signaling. Using virus-induced-gene-silencing （VIGS）, 2-Cys Peroxiredoxin （2CysPrx） family and type-II Peroxiredoxin B （PrxI B） gene were silenced in Nicotiana benthamiana, to study the impact that the loss of function of each Prx would have in the antioxidant system under control （22℃） and severe heat stress conditions （48 ℃）. The results showed that both Prxs, although in different organel es, influence the regeneration of ascorbate to a significant extent, but with different purposes. 2CysPrx affects abscisic acid （ABA） biosynthesis through ascorbate, while PrxIIB does it probably;through the xanthophyl cycle. Moreover, 2CysPrx is key in H2O2 scavenging and in consequence in the regulation of ABA signal-ing downstream of reactive oxygen species and PrxIIB provides an important assistance for H2O2 peroxisome scavenges.

关键词： 2-Cys Peroxiredoxin abscisic acid ascorbate heat stress hydrogen peroxide peroxisome type-Ⅱ Peroxiredoxin B

Natural Mg silicates with different structures and morphologies: Reaction with K to produce K2MgSiO4 catalyst for biodiesel production

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International Journal of Minerals,Metallurgy and Materials 2020年第1期27卷 46-54页

作者： Fabiane carvalho Ballotin Mayra Nascimento Sara Silveira Vieira Alexandre carvalho Bertoli Ottávio Carmignano ana Paula de carvalho Teixeira Rochel Montero Lago departamento de Química Universidade Federal de Minas GeraisBelo HorizonteBrasil Doutorado Inovação/Mineradora Pedras Congonhas Universidade Federal de Minas Gerais31270-901 Belo Horizonte-MGBrazil

In this work, different magnesium silicate mineral samples based on antigorite, lizardite, chrysotile(which have the same general formula Mg3Si2O5(OH)4), and talc(Mg3Si4O10(OH)2) were reacted with KOH to prepare catalysts for biodiesel production. Simple impregnation with 20 wt% K and treatment at 700–900°C led to a solid-state reaction to mainly form the K2MgSiO4 phase in all samples. These results indicate that the K ion can diffuse into the different Mg silicate structures and textures, likely through intercalation in the interlayer space of the different mineral samples followed by dehydroxylation and K2MgSiO4 formation. All the materials showed catalytic activity for the transesterification of soybean oil(1:6 of oil : methanol molar ratio, 5 wt% of catalyst, 60°C). However, the best results were obtained for the antigorite and chrysotile precursors, which are discussed in terms of mineral structure and the more efficient formation of the active phase K2MgSiO4.

关键词： silicate serpentinite lizardite antigorite talc chrysotile biodiesel

Association of Helicobacter pylori infection and giardiasis: Results from a study of surrogate markers for fecal exposure among children

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World Journal of Gastroenterology 2005年第18期11卷 2759-2763页

作者： Edson Duarte Moreira Jr Victor Bastos Nassri Rafaela Sousa Santos Junísia Ferraz Matos Wilson Andrade de carvalho Célia Stolve Silvani Círia Santana e Sant'ana Núcleo de Apoio à Pesquisa Fundac■o Irm■ Dulce Salvador Bahia Brazil Centro de Pesquisas Goncalo Moniz Fundac■o Oswaldo Cruz Salvador Bahia Brazil Diretoria Científica e Laboratório do Hospital S■o Rafael Salvador Bahia Brazil Núcleo de Apoio à Pesquisa Fundac■o Irm■Dulce Salvador Bahia Brazil Centro de Pesquisas Goncalo Moniz Fundac■o Oswaldo Cruz Salvador Bahia Brazil Diretoria Científica e Laboratório do Hospital S■o Rafael Salvador Bahia Brazil Diretoria Científica e Laboratório do Hospital S■o Rafael Salvador Bahia Brazil Diretoria Científica e Laboratório do Hospital S(?)o Rafael Salvador Bahia Brazil Núcleo de Apoio à Pesquisa Fundac(?)o Irm(?) Dulce Salvador Bahia Brazil

AIM: To investigate whether Helicobacter pylori (H pylori) infection is associated with hepatitis A virus (HAV) infection, presence of enteroparasites, and other surrogates of fecal exposure. METHODS: We conducted a cross-sectional study in 121 children consecutively admitted at a pediatric hospital in Salvador, Brazil. H pyloriand HAV infection were identified by the presence of serum antibodies. Stool specimens were examined for the presence of ova and parasites. A structured questionnaire inquiring about sanitary conditions and life style was applied to each subject. RESULTS: Fifty-one of the 121 children (42.1%) were found to be seropositive for H pylori, and 45 (37.2%) for HAV. The seroprevalence of Hpyloriand HAV both increased significantly with age. Cross-tabulation of data showed that 26 (21.5%) were seropositive and 51 (42.1%) were negative for both H py/lriand HAV antibodies (x^2=7.18, OR=2.8, CI 1.30-5.97). The age adjusted OR for an HAV-infected child being H pylori positive was 2.3 (CI 1.02-5.03). The agreement between H pylori and HAV seropositivity was fair (k=0.24). After controlling for possible confounding, the variables remaining independently associated with seropositivity to H pylori were age, presence of Giardia lamblia in feces (OR=3.2, 95%CI, 1.1-9.5) and poor garbage disposal quality (OR=2.4, 95%CI, 1.1-5.1). CONCLUSION: Our data suggest that H pylori infection is associated with surrogate markers of fecal exposure. Thus, we conclude that the fecal-oral route is relevant in the transmission of HP among children in an urban setting of a developing country. The association observed between G. lamblia and H pylori infection may have several explanations. Further studies to investigate this relationship are warranted.

关键词： H pylori Hepatitis A virus Epidemiology Transmission Enteroparasites Brazil

Distal renal tubular acidosis:genetic causes and management

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World Journal of Pediatrics 2019年第5期15卷 422-431页

作者： Sílvia Bouissou Morais Soares Luiz Alberto Wanderley de Menezes Silva Flávia Cristina de carvalho Mrad ana Cristina Simoes e Silva Interdisciplinary Laboratory of Medical Investigation Faculty of MedicineFederal University of Minas Gerais(UFMG)Av.Prof.Alfredo Balena190Room#281Belo HorizonteMG 30130-100Brazil Pediatric Nephrology Unit Faculty of MedicineUFMGBelo HorizonteBrazil

Background Distal renal tubular acidosis(dRTA)is a kidney tubulopathy that causes a state of normal anion gap metabolic acidosis due to impairment of urine *** review aims to summarize the etiology,pathophysiology,clinical findings,diagnosis and therapeutic approach of dRTA,with emphasis on genetic causes of *** sources Literature reviews and original research articles from databases,including PubMed and Google *** searching was performed to identify additional studies about *** dRTA is characterized as the dysfunction of the distal urinary acidification,leading to metabolic *** pediatric patients,the most frequent etiology of dRTA is the genetic alteration of genes responsible for the codification of distal tubule channels,whereas,in adult patients,dRTA is more commonly secondary to autoimmune diseases,use of medications and *** with dRTA exhibit failure to thrive and important laboratory alterations,which are used to define the *** oral alkali and potassium supplementation can correct the biochemical defects,improve clinical manifestations and avoid nephrolithiasis and *** dRTA is a multifactorial disease leading to several clinical *** and laboratory alterations can be corrected by alkali replacement therapy.

关键词： Renal tubular acidosis Distal tubule physiology Metabolic acidosis Gene mutations Proton pump

Thermal and Mechanical Properties of Thermoplastic Starch and Poly(Vinyl Alcohol-Co-Ethylene)Blends

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Journal of Renewable Materials 2019年第3期7卷 245-252页

作者： ana Clara Lancarovici Alves Rafael Grande Antonio José Felix carvalho department of Materials Engineering Sao Carlos School of EngineeringUniversity of Sao PauloAv.Joao Dagnone110013563-120Sao Carlos-SP-Brazil

The interest in thermoplastic starch(TPS)as a substitute material to replace conventional thermoplastics continues especially due its biodegradability,availability,low cost and because it is obtained from renewable ***,its poor mechanical properties and its high sensitivity to humidity have limited its use in several ***,the copolymer poly(ethylene-co-vinyl alcohol)(EVOH),with two different ethylene contents,27 and 44 mol%were blended with TPS by extrusion in order to overcome these *** obtained blends were characterized by thermogravimetric analysis(TGA),differential scanning calorimetry(DSC),mechanical tensile testing,Scanning Electron Microscopy(SEM)and moisture absorption *** addition of EVOH copolymer did not significantly changed the thermal stability of TPS,however it increased the tensile strength in 65%when compared to *** morphology of the blends did not showed two distinct phases,an indication of miscibility or partial miscibility of the components.A decrease of moisture absorption was obtained by the addition of EVOH and is more pronounced for the EVOH with 44% of ethylene.

关键词： Thermoplastic starch EVOH polymer blends thermal properties of polymers mechanical properties of polymers

design multifunctional Mg–Zr coatings regulating Mg alloy bioabsorption

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Journal of Magnesium and Alloys 2024年第4期12卷 1461-1478页

作者： Zohra Benzarti Sandesh Itani JoséDavid Castro Sandra carvalho ana Sofia Ramos University of Coimbra CEMMPREARISEDepartment of Mechanical EngineeringRua Luís Reis Santos3030-788CoimbraPortugal Laboratory of Multifunctional Materials and Applications(LamMA) Department of PhysicsFaculty of Sciences of SfaxUniversity of SfaxSoukra Road km 3.5B.P.1171Sfax3000Tunisia

Magnesium(Mg)alloys are widely used for temporary bone implants due to their favorable biodegradability,cytocompatibility,hemocompatibility,and close mechanical properties to ***,rapid degradation and inadequate strength limit their *** overcome this,the direct current magnetron sputtering technique is employed for surface coating in Mg-based alloys using various zirconium(Zr)*** approach presents a promising strategy for simultaneously improving corrosion resistance,maintaining biocompatibility,and enhancing strength without compromising *** leveraging Mg’s inherent biodegradability,it has the potential to minimize the need for secondary surgeries,thereby reducing costs and *** paper is a systematic study aimed at understanding the corrosion mechanisms of Mg–Zr coatings,denoted Mg-xZr(x=0–5 at.%).Zr-doped coatings exhibited columnar growth leading to denser and refined structures with increasing Zr *** analysis confirmed the presence of the Mg(00.2)basal plane,shifting towards higher angles(1.15°)with 5 at.%Zr doping due to lattice parameter changes(i.e.,decrease and increase of“c”and“a”lattice parameters,respectively).Mg–Zr coatings exhibited“liquidphilic”behavior,while Young’s modulus retained a steady value around 80 GPa across all ***,the hardness has significantly improved across all samples’coating,reaching the highest value of(2.2±0.3)GPa for 5 at.%*** testing in simulated body fluid(SBF)at 37℃ revealed a significant enhancement in corrosion resistance for Mg–Zr coatings containing 1.0–3.4 at.%*** with the 5 at.%Zr coating which exhibited a corrosion rate of 32 mm/year,these coatings displayed lower corrosion rates,ranging from 1 to 12 mm/*** synergistic enhancement in mechanical properties and corrosion resistance,achieved with 2.0–3.4 at.%Zr,suggests potential ability for reducing stress shielding and controlled degradation performance,and consequentl

关键词： Mg-Zr coatings Magnetron sputtering Nanoindentation Corrosion resistance Bone implants

Bioaccessibility of phenolic compounds from Brazilian grape juices using a digestion model with intestinal barrier passage

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Food Bioscience 2023年第2期52卷 1343-1351页

作者： Maria da Conceicao Prudencio Dutra ana Beatriz Martins da Silva Ederlan de Souza Ferreira ana Julia de Brito Araujo carvalho Marcos dos Santos Lima Aline Camarao Telles Biasoto Graduate Program in Food Science Faculty of PharmacyFederal University of BahiaSalvadorBahiaBrazil Federal Institute of Education Science and Technology of Sertao PernambucanoLiquid Chromatography LaboratoryCampus IndustrialPetrolinaPernambucoBrazil Brazilian Agricultural Research Corporation Embrapa Semi-arid RegionPetrolinaPernambucoBrazil Brazilian Agricultural Research Corporation Embrapa EnvironmentJaguariunaSao PauloBrazil

Grape juices are rich in bioactive compounds;however,for these compounds to exert their functionality,they must be ***,the present study evaluated a simulated digestion process on the main bioactive compounds of monovarietal grape juices of five Brazilian hybrid cultivars(*** x ***).Characterization of the chemical profiles in liquid chromatography(HPLC-DAD-RID),behaviour of phenolics in the stages of digestion and bioaccessibility through the INFOGEST protocol plus intestinal barrier passage were carried *** the 24 polyphenols identified in the grape juice samples,11 were bioaccessible,with emphasis on the class of *** B2(101-426%),(+)-catechin(169-370%)and gallic acid(61-230%)stood out in all juices,showing that these compounds are key to the functionality of these *** were observed to differ between juices,demonstrating that factors such as the cultivar should be explored more extensively in studies on functional *** study also suggests that quality components such as sugars and organic acids influence the bioaccessibility of beverages.

关键词： Grape cultivars Functional beverages Phytochemicals Digestion simulation Bioactivity

Review of small-bowel cleansing scales in capsule endoscopy: A panoply of choices

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World Journal of Gastrointestinal Endoscopy 2016年第17期8卷 600-609页

作者： ana Ponte Rolando Pinho Adélia Rodrigues Joao carvalho department of Gastroenterology Centro Hospitalar Vila Nova de Gaia/Espinho Vila Nova de Gaia 4434-502 Porto Portugal

Evaluation of the quality of small-bowel cleansing is required to assess the reliability of findings in capsule endoscopy(CE). Moreover, consensus regarding the need of intestinal preparation for CE remains to be achieved. The presence of multiple grading scales for smallbowel preparation in CE, which are time-consuming and complicated, adds difficulty to the comparison of different small-bowel cleansing regimens and their application in clinical practice. Nowadays, a validated scale universally accepted for grading small-bowel cleansing is lacking. In fact, there are numerous grading systems with very different technical characteristics, namely, the parameters and the portion of the CE video that are analyzed, the objectivity of the analysis, the lesser or greater dependency on the operator, and the validation of the score. The authors performed a review which aims to systematize and summarize currently available smallbowel grading scales in CE.

关键词： Capsule endoscopy Small-bowel Smallbowel Cleansing Scales Enteroscopy Grading

Haploidentical hematopoietic stem cell transplantation as promising therapy in the improved survival of pediatric patients with leukemias and myelodysplasias

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World Journal of Meta-analysis 2023年第5期11卷 181-195页

作者： ana Clara carvalho Cardoso Brito Everton Oliveira Carneiro Ribeiro Fabrício Freire de melo Instituto Multidisciplinar em Saúde Universidade Federal da BahiaVitória da Conquista 45029-094BahiaBrazil

BACKGROUND Haploidentical hematopoietic stem cell transplantation(Haplo-HSCT)is often performed in children with hematologic *** with the gap in the literature regarding the approach to experiences related to Haplo-HSCT with pediatric patients with leukemias and myelodysplasias aged up to 18 years,there was an interest in exploring the clinical outcomes of patients undergoing this *** To identify and summarize the scientific contributions available on Haplo-HSCT performed in the last 10 years in children and adolescents with myeloid and lymphoid leukemias and myelodysplasias,aged up to 18 *** This is a descriptive systematic *** extracted data including characteristics of participants,health condition,characteristics of the donation,conditioning regimen,recurrent clinical complications and clinical *** Virtual Health Library Brazil,PubMed,EMBASE,and SciELO platforms were used,finding a total of 1052 *** the eligibility criteria and complete reading of the texts,18 articles were included for *** The total sample of all study cohorts was 1825 patients,mostly male,the highest reported median age was 15.0 years and the lowest was 1.2 *** graftversus-host disease and chronic graft-versus-host disease were observed in almost all ***,graft rejection and delayed immune recovery were identified as major clinical ***-transplant minimal positive residual disease was identified in 288 *** are also among the main clinical complications,viral,bacterial and fungal infections being *** is observed that in the 5-year interval,the lowest rates of EFS and overall survival(OS)were 29.5%and 68.0%,***,the highest rates of EFS and OS,in the same interval,were 80.1%and 81.0%.CONCLUSION Haplo-HSCT represents a promising therapy,considering the potential number of possible donors and the conditioning and treatment platforms that can be *** res

关键词： Haploidentical Stem cell transplantation Children Cancer Treatment outcome Prognosis