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protective effect of ascorbic acid in experimental gastric cancer: reduction of oxidative stress

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World Journal of Gastroenterology 2003年第3期9卷 446-448页

作者： Claudia p.M.S.Oliveira paulo Kassab Fabio p.Lopasso Heraldo p.souza Mariano Janiszewski Francisco R.M.Laurindo Kioshi Iriya Antonio A.Laudanna department of Gastroenterology of Medical School of University of So paulo (USp) So PauloBrazil department of Emergency Medicine of Mcdical School of University of So paulo (USp) So PauloBrazil Heart Institute of Medical School of University of So paulo (USp) So PauloBrazil depatment of pathology of Medical School of University of So paulo (USp) So PauloBrazil

AIM;Oxidative stress participates in the cell carcinogenesis by inducing DNA *** aim was to assess whether ascorbic acid,an antioxidant,could have a role in preventing ROS(Reactive Oxygen Species)generation in experimental gastric carcinoma in a rat model. METHODS:Experimental gastric cancer was induced in twelve Wistar male rats(weighting 250-350 g)by profound duodeno-gastric reflux throught split *** rats were allocated to the following groups:Group Ⅰ(n=6) was the control;Group Ⅱ(n=6)which was mantained with daily intake of tape water with Vitamin C(30 mg/Kg).After 6 or 12 months,samples of gastric tumor or non tumor mucosa were taken from the anastomosis of both groups. Oxidative stress was measured by superoxide quantification through lucigenin-amplified chemiluminescence base and by staining with *** histopathologic confirmation of adenocarcinoma was made by eosin- hemathoxilin method. RESULTS:The intestinal type of gastric adenocarcinoma was microscopically identified in all animals of group Ⅰ whereas only 3 rats of group Ⅱ showed an adenocarcinoma without macroscopic evidence of *** cancers were located in the anastomosis in all *** luminescence from tumor gastric tissue generated 38.4±6.8 count per minute/mg/×10~6(mean±SD)and 14.9±4.0 count per minute/mg/×10~6,respectively,in group Ⅰ and Ⅱ animals(p plasic mucosa. CONCLUSION:Experimental gastric tumors seem to produce more reactive oxygen species than non neoplasic gastric *** reduction of oxidative stress and gastric tumor incidence in rats were induced by the intake of ascorbic ***,it may have a role in the prevention of gastric carcinoma. Oliveira CpMS Kassab p Lopasso Fp souza Hp Janiszewski M Laurindo FRM Iriya K Laudanna *** effect of ascorbic acid in experimental gastric cancer:reduction of oxidative *** J G

关键词： Animals Antioxidants Ascorbic Acid Male Oxidative Stress Rats Rats, Wistar Stomach Neoplasms control

Biofilm analyses and exoproduct release by clinical and environmental isolates of Burkholderia pseudomallei from Brazil

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Asian pacific Journal of Tropical Medicine 2023年第7期16卷 321-328页

作者： Glaucia Morgana de Melo Guedes Crister JoséOcadaque Alyne Soares Freitas Rodrigo Machado pinheiro Giovanna barbosa Riello Silviane praciano Bandeira Rossana de Aguiar Cordeiro Marcos Fábio Gadelha Rocha JoséJúlio Costa Sidrim Débora de souza Collares Maia Castelo-Branco department of pathology and Legal Medicine Postgraduate Program in Medical MicrobiologyGroup of Applied Medical MicrobiologyFederal University of CearáFortalezaCEBrazil department of Clinical and Toxicological Analysis School of PharmacyFederal University of CearáFortalezaCEBrazil department of pathology and Legal Medicine Postgraduate Program in Medical MicrobiologyLaboratory of Emerging and Reemerging PathogensFederal University of CearáFortalezaCEBrazil School of Veterinary Medicine Postgraduate Program in Veterinary SciencesState University of CearáFortalezaCEBrazil

Objective:To characterize biofilm production by clinical(n=21)and environmental(n=11)isolates of Burkholderia pseudomallei and evaluate the production of proteases,hemolysins and ***:Initially,the 32 strains were evaluated for biofilm production in Müller-Hinton broth-1%glucose(MH-1%glucose)and BHI broth-1%glucose,using the crystal violet staining ***,growing(48 h)and mature(72 h)biofilms were evaluated by confocal ***,the production of proteases,hemolysins and siderophores by planktonic aggregates,growing biofilms and mature biofilms was ***:All isolates produced biofilms,but clinical isolates had significantly higher biomass in both MH-1%glucose(pp=0.005).The structural analyses by confocal microscopy showed thick biofilms,composed of multiple layers of cells,homogeneously arranged,with mature biofilms of clinical isolates presenting higher biomass(p=0.019)and thickness of the entire area(p=0.029),and lower roughness coefficient(p=0.007)than those of environmental *** production by growing biofilms was significantly greater than that of planktonic(ppplanktonic aggregates was higher than that of biofilms(pderophores,mature biofilms presented higher production than growing biofilms(pplanktonic aggregates(pproduction of biofilms than their environmental counterparts;protease and siderophores seem important for growth and maintenance of Burkholderia pseudomallei biofilms.

关键词： Mangosteen Burkholderia pseudomallei Biofilms proteases Hemolysins Siderophores

Sex recognition does not modulate aggression toward nest intruders in a paper wasp

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Current Zoology 2023年第3期69卷 324-331页

作者： Andre Rodrigues de souza Wilson Franca Amanda prato Fabio Santos do Nascimento departamento de Biologia Faculdade de Filosofia Ciencias e Letras de Ribeirao PretoUniversidade de Sao PauloSao PauloBrazil

During social interactions,the behavior of an individual often depends on the sex of its social *** animal societies have males and females that play very different behavioral roles,although they coexist and interact *** specific phases of the colony cycle,social wasp females and males are contemporaries within a nest,they often interact,although mating occurs mostly off the nest,therefore providing an opportunity to test sex discrimination in contexts other than classical sexual *** performed a lure presentation experiment to test if Mischocyttarus metathoracicus discriminate between conspecifics of the 2 sexes during on-nest social *** wasps discriminated conspecific sex during experimentally simulated nest *** and chemical cues may account for this sex *** sex discrimination(evidenced by differential inspective behavior from the nest females toward the female and the male lures),female wasps were as aggressive toward lures of both *** the female-dominated hymenopteran societies,males are often subordinate and not aggressive on nest,resulting in females directing less aggression to them compared to other ***,*** males and females are both aggressive toward nestmates,so they might be perceived as similar threat during on-nest social interactions.

关键词： chemical cues Mischocyttarus sex discrimination social interactions social wasps visual cues

Metabolomics-assisted refinement of the pathways of steroidal glycoalkaloid biosynthesis in the tomato clade

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Journal of Integrative plant Biology 2014年第9期56卷 864-875页

作者： Kevin Schwahn Leonardo perez de souza Alisdair R.Fernie Takayuki Tohge University of potsdam AG BioinformaticsInstitute for Biochemistry and Biology Maxplanck-Institute of Molecular plant physiology

Steroidal glycoalkaloids（SGAs） are nitrogen-containing secondary metabolites of the Solanum species,which are known to have large chemical and bioactive diversity in *** recent effort and development on LC/MS techniques for SGA profiling have elucidated the main pathways of SGA metabolism in tomato,the problem of peak annotation still remains due to the vast diversity of chemical structure and similar on overlapping of chemical *** we provide a case study of peak classification and annotation approach by integration of species and tissue specificities of SGA accumulation for provision of comprehensive pathways of SGA *** order to elucidate natural diversity of SGA biosynthesis,a total of 169 putative SGAs found in eight tomato accessions（Soianum lycopersicum, ***, ***, ***, ***,***,***,***） and four tissue types were used for correlation *** results obtained in this study contribute annotation and classification of SGAs as well as detecting putative novel biosynthetic branch *** such this represents a novel strategy for peak annotation for plant secondary metabolites.

关键词： Fruit ripening glycoalkaloids secondary metabolite Solanum lycopersicum tomato accessions

Litter decomposition and nutrient release for two tropical N-fixing species in Rio de Janeiro,Brazil

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Journal of Forestry Research 2022年第2期33卷 487-496页

作者： David pessanha Siqueira Giovanna Campos Mamede Weiss de Carvalho JoséGabriel de souza Silva Marcos Vinicius Winckler Caldeira deborah Guerra Barroso Laboratório de Fitotecnia Universidade Estadual do Norte Fluminense Darcy RibeiroAvenida Alberto Lamego2000Campos dos GoytacazesRio de JaneiroBrazil departamento de Ciências Florestais e da Madeira Universidade Federal do Espírito SantoAvenida Governador Lindenberg316Jerônimo MonteiroEspírito SantoBrazil department of Geosciences and Natural Resources Management University of CopenhagenRolighedsvej 23Frederisksberg CDenmark

Litter production and decomposition are critical to forest productivity,nutrient cycling,and carbon seques-tration in tropical woody ***,nutrient release and leaf litter stoichiometry in tropical legume tree plantations over the long term after outplanting are poorly understood or even *** improving our under-standing of the pattern of changes in the decomposition of N-fixing leaf litters and their possible impact on carbon stor-age,we measured litter production,mass loss and nutrient release for 240 d during litter decomposition for two tropical legume tree species(plathymenia reticulata and Hymenaea courbaril),in Rio de Janeiro,*** production for *** was 5.689 kg ha^(−1) a^(−1) and 3.231 kg ha^(−1) a^(−1) for *** patterns of mass loss rates were similar;however,nutrient release was greater for ***,while *** showed immobilization of nutrients,especially for N,which increased by almost 20%in the early phase of decomposition followed by gradual *** from the N-fixing species did differ in nutrient chemistries over time,which was not surprising given that initial nutrient concentrations varied broadly,except for C and *** of the nutrient concentrations increased as the remaining litter mass decreased in both species,except for C and *** C:N and N:p ratios differed between the species,but N:p did not correlate to mass *** species had N-rich leaves,but *** decomposition was very likely p-limited,while *** seemed to be co-limited by N and *** results showed different patterns in nutrient release and the stoichi-ometry involved in the decomposition dynamics of the two tropical N-fixing species,even though they have similar litter decay *** species,but especially ***,may help re-establish nutrient cycling in disturbed ecosystems.

关键词： Nutrient dynamics Legume species Litter chemistry Ecological stoichiometry Tropical forest

partition coefficient prediction of Baker's yeast invertase in aqueous two phase systems using hybrid group method data handling neural network

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Chinese Journal of Chemical Engineering 2017年第5期25卷 652-657页

作者： Carlos Eduardo de Araújo padilha Sérgio Dantas de Oliveira Júnior Domingos Fabiano de Santana souza Jackson Araújo de Oliveira Gorete Ribeiro de Macedo Everaldo Silvino dos Santos Laboratory of Biochemical Engineering Chemical Engineering DepartmentFederal University of Rio Grande do Norte (UFRN)

A hybrid GMDH neural network model has been developed in order to predict the partition coefficients of invertase from Baker's yeast. ATpS experiments were carried out changing the molar average mass of pEG(1500–6000 Da), p H(4.0–7.0), percentage of pEG(10.0–20.0 w/w), percentage of MgSO_4(8.0–16.0 w/w), percentage of the cell homogenate(10.0–20.0 w/w) and the percentage of MnSO_4(0–5.0 w/w) added as cosolute. The network evaluation was carried out comparing the partition coefficients obtained from the hybrid GMDH neural network with the experimental data using different statistical metrics. The hybrid GMDH neural network model showed better fitting(AARD = 32.752%) as well as good generalization capacity of the partition coefficients of the ATpS than the original GMDH network approach and a BpANN model. Therefore hybrid GMDH neural network model appears as a powerful tool for predicting partition coefficients during downstream processing of biomolecules.

关键词： partitioning Invertase Aqueous Two phase System GMDH Neural network

Recycling process and proto-kimberlite melt metasomatism in the lithosphere-asthenosphere boundary beneath the Amazonian Craton recorded by garnet xenocrysts and mantle xenoliths from the Carolina kimberlite

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Geoscience Frontiers 2022年第5期13卷 89-105页

作者： Fernanda Gervasoni Tiago Jalowitzki Marcelo peres Rocha Ricardo Kalikowski Weska Eduardo Novais-Rodrigues Rodrigo Antonio de Freitas Rodrigues Yannick Bussweiler Elisa Soares Rocha barbosa Jasper Berndt Elton Luiz Dantas Valmir da Silva souza Stephan Klemme Centro de Engenharias Universidade Federal de Pelotas(UFPel)PelotasBrazil programa de pós-graduação em Geociências Universidade Federal do Rio Grande do SulPorto AlegreBrazil programa de pós-graduação em Geologia Instituto de GeociênciasUniversidade de Brasília(UnB)BrasíliaBrazil Faculdade de Geociências Universidade Federal do Mato Grosso(UFMT)CuiabáBrazil Institut für Geologie und Mineralogie Universität zu KölnGermany Faculdade de Ciências e Tecnologia Universidade Federal de Goiás(UFG)Aparecida de GoiâniaBrazil Institut für Mineralogie Universität MünsterMünsterGermany

Here we present new data on the major and trace element compositions of silicate and oxide minerals from mantle xenoliths brought to the surface by the Carolina kimberlite,pimenta Bueno Kimberlitic Field,which is located on the southwestern border of the Amazonian *** also present Sr-Nd isotopic data of garnet xenocrysts and whole-rocks from the Carolina *** xenoliths are mainly clinopyroxenites and *** of the clinopyroxenites were classified as Gpp–pp–pKp(garnet-phlogopite peridotite,phlogopite-peridotite,phlogopite-K-richterite peridotite)suites,and two clinopyroxenites(eclogites)and two garnetites are relicts of an ancient subducted *** and pressure estimates yield 855–1102℃ and 3.6–7.0 Gpa,*** are enriched in light rare earth elements(LREE)(La_(N)/Yb_(N)=5–62;Ce_(N)/Sm_(N)=1–3;where N=primitive mantle normalized values),they have high Ca/Al ratios(10–410),low to medium Ti/Eu ratios(742–2840),and low Zr/Hf ratios(13–26),which suggest they were formed by metasomatic reactions with CO_(2)-rich silicate *** with high TiO_(2)(>2.0 wt.%),Al_(2)O_(3)(>12.0 wt.%),and FeOt(5.0–13.0 wt.%)resemble those found in the groundmass of kimberlites,lamproites and ***,phlogopite with low TiO_(2)(present in Gpp-pp-pKp,and in MARID(mica-amphibole-rutile-ilmenite-diopside)and pIC(phlogopite-ilmenite-clinopyorxene)*** Gpp-pp-pKp suite of xenoliths,together with the clinopyroxene and phlogopite major and trace element signatures suggests that an intense proto-kimberlite melt metasomatism occurred in the deep cratonic lithosphere beneath the Amazonian *** Sr-Nd isotopic ratios of pyrope xenocrysts(G3,G9 and G11)from the Carolina kimberlite are characterized by high ^(143)Nd/^(144)Nd(0.51287–0.51371)and eNd(+4.55 to+20.85)accompanied with enriched ^(87)Sr/^(86)Sr(0.70405–0.71098).These results suggest intera

关键词： Carolina kimberlite K-rich mantle xenoliths Ancient subducted slab proto-kimberlite melt metasomatism

Growth and nutrient accumulation of Brazil nut trees(Bertholletia excelsa) in agroforestry at different fertilizer levels

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Journal of Forestry Research 2015年第2期26卷 347-353页

作者： Gotz Schroth Maria do Socorro souza da Mota Maria Elizabeth de Assis Elias C.p. 513 Santarem PA 68109-971 Brazil Centro de Estudos Avanqados de promoqao Social e Ambiental Av. Mendonqa Furtado 3979 Santarem PA 68040-050 Brazil Universidade Federal do Amazonas Manaus AM 69077-000Brazil

The Brazil nut tree（Bertholletia excelsa） is a frequent component of agroforestry systems in the Amazon because of its adaptation to nutrient-poor upland soils and multiple *** investigated the aboveground biomass production（kg dry weight）,nutrient uptake and requirements（N,p,Ca,Mg,K） of Brazil nut trees of different sizes grown under agroforestry conditions and fertilized at different *** of 70 experimental trees with different size were harvested and stem,branches and leaves were *** contents were determined for three trees of varying *** tree growth was fast,but variability was high,suggesting considerable potential for the improvement of this economically important *** trees responded to increased levels of fertilizer and lime with significantly increased foliar nutrient contents and growth,probably because of the improved availability of Mg and Ca for which the species seems to have a relatively high *** contrast to Brazil nut trees grown in forest or dense plantations,the agroforestry trees invested a substantial part of their biomass and nutrients in large branches and developed spreading *** improve stem form,reduce competition with associated crops for light and recycle nutrients,regular pruning of lower branches or planting arrangements that favor self-pruning are *** measures would also increase the recycling of Ca and Mg,large quantities of which are contained in the branches.

关键词： Allometric equation Amazon Nutrient competition Nutrient recycling plant mineral nutrition Soil fertility Silviculture

Metabolizable energy,nitrogen balance,and ileal digestibility of amino acids in quality protein maize for pigs

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Journal of Animal Science and Biotechnology 2014年第4期5卷 461-470页

作者： Gerardo Mariscal-Landin Tercia Cesaria Reis de souza Ericka Ramirez Rodriguez CENID Fisiologia Instituto Nacional de Investigaciones Forestales Agricolas y Pecuariaskm 1 Carretera a Ajuchitlan76280 QueretaroMexico Facultad de Ciencias Naturales Universidad Autonoma de QueretaroMexicoAv.de las Ciencias s/n76230 QueretaroMexico

Background：To compare the nutritional value and digestibility of five quality protein maize（QpM） hybrids to that of white and yellow maize,two experiments were carried out in growing *** experiment 1,the energy metabolizability and the nitrogen balance of growing pigs fed one of five QpM hybrid diets were compared against those of pigs fed white or yellow *** experiment 2,the apparent and standardized ileal digestibility（AID and SID,respectively） of proteins and amino acids from the five QpM hybrids were compared against those obtained from pigs fed white and yellow *** both experiments,the comparisons were conducted using ***：The dry matter and nitrogen intakes were higher in the pigs fed the QpM hybrids（p 〈 0.05） than in the pigs fed white or yellow *** digestibility（p 〈 0.001） and metabolizability（p 〈 0.01） were higher in the pigs fed the white and yellow maize diets than in those fed the QpM *** AID of lysine was higher（p〈 0.01） in the QpM diets than in the white and yellow *** AIDs of leucine,isoleucine,valine,phenylalanine,and methionine were lower in the QpM diets than those of maize（white and yellow）（all p 〈 0.05）.Maize（white and yellow） had greater SIDs of leucine,isoleucine,valine,phenylalanine,glutamic acid,serine,alanine,tyrosine,and proline（p 〈 0.05）.Conclusions：Based on these results,it was concluded that QpM had a lower metabolizable energy content and a higher amount of digestible lysine than normal maize.

关键词： Amino acids Energy balance Maize Nitrogen balance pigs