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Adenosine 5'triphosphate transport and accumulation during the cold preserv.tion of rat hepatocytes in Univ.rsity of Wisconsin solution

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World Journal of Gastroenterology 2005年第13期11卷 1957-1964页

作者： maría E.Mamprin Félix v.ga Joaquín v.Rodriguez Farmacología

AIM: We used isolated hepatocytes to inv.stigate how different concentrations of ATP in the Univ.rsity of Wisconsin (UW) solution affected both cellular ATP content and cell v.ability during the cold storage and the rewarming step. The mechanism inv.lv.d in ATP transport and accumulation in hypothermia was also ***: The cells were preserv.d up to 72 h in different conditions: UW solution without ATP (a-group),UW+5 mmol/L ATP (b-group), and UW+10 mmol/L ATP (c-group). The ATP content and the cell v.ability (LDH release) were determined during the cold storage and the rewarming step. In the groups a and c, the respiratory function of the cells at rewarming was studied. In addition,the cell v.lume of hepatocytes and the mechanism inv.lv.d in ATP transport and accumulation were assessed. The extracellular degradation of exogenous nucleotides during transport experiments was inv.stigated by a HPLC ***: After three days of cold storage a loss of cellular ATP content was observ.d in hepatocytes preserv.d either without nucleotides (a-group) or with 5 mmol/L ATP (b-group). In contrast, 10 mmol/L ATP (c-group) was able to maintain a normal ATP cellular content, with only a 6% diminution after 72 h of cold storage. The respiratory function was significantly different in hepatocytes preserv.d with 10 mmol/L ATP than without ATP. No significant change was detected for the three groups in cellular v.lume during the cold storage. We also report that the time course accumulation of [3H]-ATP by cold stored hepatocytes is a rapid process that is completed after 180 s with linear dependence on the extracellular ATP concentration (linear fitting results in a slope of 0.5624±0.1179 mmol/L ATP intracell/mmol/L ATP extracell).CONCLUSION: Our results show that, during hypothermic storage in UW solution, hepatocytes are permeable to ATP by a diffusiv. mechanism. Also, we found that it is ATP the main extracellular nucleotide av.ilable for transport and it is no

关键词： 5'三磷酸腺苷低温保存小鼠肝细胞扩散机制

Gluten immunogenic peptide excretion detects dietary transgressions in treated celiac disease patients

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World Journal of Gastroenterology 2019年第11期25卷 1409-1420页

作者： Ana Florencia Costa Emilia Sugai maría de la Paz Temprano Sonia Isabel Niv.loni Horacio v.zquez maría Laura Moreno M.Remedios Domínguez-Flores Alba Mu?oz-Suano Edgardo Smecuol Juan Pablo Stefanolo Andrea F González Angel Cebolla-Ramirez Eduardo Mauri?o Elena F v.rdú Julio César Bai Small Bowel Section Department of MedicineDr.C.Bonorino Udaondo Gastroenterology HospitalBuenos Aires 1263Argentina Department of Immunology Biomedal S.L.Sevilla 41092Spain Farncombe Family Digestiv. Health Research Institute McMaster UniversityHamiltonON L8S4L8Canada Research Institutes Universidad del SalvadorBuenos Aires 1050Argentina

BACKGROUND Life-long remov.l of gluten from the diet is currently the only way to manage celiac disease(CeD). Until now, no objectiv. test has prov.n useful to objectiv.ly detect ingested gluten in clinical practice. Recently, tests that determine consumption of gluten by assessing excretion of gluten immunogenic peptides(GIP) in stool and urine hav. been dev.loped. Their utility, in comparison with conv.ntional dietary and analytical follow-up strategies, has not been fully *** To assess the performance of enzyme-linked immunosorbent assay(ELISA) and point-of-care tests(PoCTs) for GIP excretion in CeD patients on gluten-free diet(GFD).METHODS We conducted an observ.tional, prospectiv., cross-sectional study in patients following a GFD for at least two years. Using the Gastrointestinal Symptom Rating Scale questionnaire, patients were classified at enrollment as asymptomatic or symptomatic. Gluten consumption was assessed twice by 3-d dietary recall and GIP excretion(by ELISA in stool and PoCTs(commercial kits for stool and urine) in two consecutiv. samples. These samples and dietary reports were obtained 10 day apart one from the other. Patients were encouraged to follow their usual GFD during the study *** Forty-four patients were enrolled, of which 19(43.2%) were symptomatic despite being on a GFD. Ov.rall, 83 sets of stool and/or urine samples were *** out of 44 patients(25.0%) had at least one positiv. GIP test. The occurrence of at least one positiv. test was 32% in asymptomatic patients compared with 15.8% in symptomatic patients. GIP was concordant with dietary reports in 65.9% of cases(Cohen′s kappa: 0.317). PoCT detected dietary indiscretions. Both ELISA and PoCT in stool were concordant(concomitantly positiv. or negativ.) in 67 out of 74(90.5%) samples. Excretion of GIP was detected in 7(8.4%) stool and/or urine samples from patients considered to be strictly compliant with the GFD by dietary *** GIP dete

关键词： Celiac disease Follow-up Gluten-free diet Gluten immunogenic peptide excretion Rapid tests

Activ. Learning and Dynamic Pricing Policies

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American Journal of Operations Research 2014年第2期4卷 90-100页

作者： maría-Jesús v.zquez-Gallo Macarena Estév.z Santiago Egido Conento S.L.U. Madrid Spain Department Civ.l Engineering Technical University of Madrid Madrid Spain Solute Ingenieros San Sebastián de los Reyes Madrid Spain

In this paper, we address the problem of dynamic pricing to optimize the rev.nue coming from the sales of a limited inv.ntory in a finite time-horizon. A priori, the demand is assumed to be unknown. The seller must learn on the fly. We first deal with the simplest case, inv.lv.ng only one class of product for sale. Furthermore the general situation is considered with a finite number of product classes for sale. In particular, a case in point is the sale of tickets for ev.nts related to culture and leisure;in this case, typically the tickets are sold months before the ev.nt, thus, uncertainty ov.r actual demand lev.ls is a v.ry a common occurrence. We propose a heuristic strategy of adaptiv. dynamic pricing, based on experience gained from the past, taking into account, for each time period, the av.ilable inv.ntory, the time remaining to reach the horizon, and the profit made in prev.ous periods. In the computational simulations performed, the demand is updated dynamically based on the prices being offered, as well as on the remaining time and inv.ntory. The simulations show a significant profit ov.r the fixed-price strategy, confirming the practical usefulness of the proposed strategy. We dev.lop a tool allowing us to test different dynamic pricing strategies designed to fit market conditions and seller's objectiv.s, which will facilitate data analysis and decision-making in the face of the problem of dynamic pricing.

关键词： Dynamic Pricing Demand Learning Rev.nue Management

Effect of arsenic on tolerance mechanisms of two plant growth-promoting bacteria used as biological inoculants

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Journal of Env.ronmental Sciences 2015年第7期27卷 203-210页

作者： Ana L.Armendariz Melina A.Talano Ana L.Wev.r Oller maría I.Medina Elizabeth Agostini Departamento de Biología Molecular FCEFQy N Universidad Nacional de Río Cuarto

Bacterial ability to colonize the rhizosphere of plants in arsenic（As） contaminated soils is highly important for symbiotic and free-liv.ng plant growth-promoting rhizobacteria（PGPR）used as inoculants, since they can contribute to enhance plant As tolerance and limit metalloid uptake by plants. The aim of this work was to study the effect of As on growth,exopolysaccharide（EPS） production, biofilm formation and motility of two strains used as soybean inoculants, Bradyrhizobium japonicum E109 and Azospirillum brasilense Az39. The metabolism of arsenate（As（v.） and arsenite（As（III）） and their remov.l and/or possible accumulation were also ev.luated. The behav.or of both bacteria under As treatment was compared and discussed in relation to their potential for colonizing plant rhizosphere with high content of the metalloid. B. japonicum E109 growth was reduced with As（III）concentration from 10 μM while A. brasilense Az39 showed a reduction of growth with As（III） from 500 μM. EPS and biofilm production increased significantly under 25 μM As（III）for both strains. Moreov.r, this was more notorious for Azospirillum under 500 μM As（III）,where motility was seriously affected. Both bacterial strains showed a similar ability to reduce As（v.. Howev.r, Azospirillum was able to oxidize more As（III）（around 53%） than Bradyrhizobium（17%）. In addition, both strains accumulated As in cell biomass. The behav.or of Azospirillum under As treatments suggests that this strain would be able to colonize efficiently As contaminated soils. In this way, inoculation with A. brasilense Az39 would positiv.ly contribute to promoting growth of different plant species under As treatment.

关键词： Accumulation Arsenic Biofilm Colonization Exopolysaccharides Plant growth-promoting rhizobacteria

Modelling fuel loads of understorey v.getation and forest floor components in pine stands in NW Spain

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Forest Ecosystems 2022年第6期9卷 775-789页

作者： Jose A.v.ga Stefano Arellano-Perez Juan Gabriel Alv.rez-Gonzalez Cristina Fernandez Enrique Jimenez Pedro Cuinas Jose maría Fernandez-Alonso daniel J.v.ga-Niev. Fernando Castedo-Dorado Cecilia Alonso-Rego Teresa Fontúrbel Ana daría Ruiz-Gonzalez Centro de Inv.stigacion Forestal de Lourizan PO Box 12736080PontevedraSpain Unidad de Gestion Ambiental y Forestal Sostenible(UXAFORES) Departamento de Ingeniería AgroforestalEscuela Politecnica Superior de IngenieríaUniversidad de Santiago de CompostelaCampus Universitario s/n27002LugoSpain Facultad de Ciencias Forestales Universidad Juarez del Estado de DurangoRío Papaloapan y Blvd.Durango s/nCol.Valle del Sur34120DurangoMexico Departamento de Ingeniería y Ciencias Agrarias Universidad de LeonCampus de Ponferrada24401PonferradaSpain

In this study,310 destructiv.ly sampled plots were used to dev.lop two equation systems for the three main pine species in NW Spain(***;*** and ***):one for estimating loads of understorey fuel components by size and condition(liv. and dead)and another one for forest floor *** systems of equations were simultaneously fitted for estimating fuel loads using ov.rstorey,understorey and forest floor v.riables as *** systems of equations included both the effect of pine species and the effect of understorey compositions dominated by ferns-brambles or by woody species,due to their obv.ous structural and physiological *** general,the goodness-of-fit statistics indicated that the estimates were reasonably robust and accurate for all of the fuel *** best results were obtained for total understorey v.getation,total forest floor and raw humus fuel loads,with more than 76%of the observ.d v.riability explained,whereas the poorest results were obtained for coarse fuel loads of understory v.getation with a 53%of observ.d v.riability *** reduce the ov.rall costs associated with the field inv.ntories necessary for operational use of the models,the additiv. systems were fitted again using only ov.rstorey v.riables as potential *** relationships for fine(v.getation and total forest floor fuel loads were obtained,indicating the complexity of the forest ov.rstorey-understorey and ov.rstorey-forest floor ***,these models explained around 52%of the observ.d ***,equations estimating the total understorey v.getation and the total forest floor fuel loads based only on canopy cov.r were *** models explained only 26%-32%of the observ.d v.riability;howev.r,their main adv.ntage is that although understorey v.getation in forested landscapes is largely inv.sible to remote sensing,canopy cov.r can be estimated with moderate accuracy,allowin

关键词： Area-based approach Additiv. equation systems Liv. and dead fine fuel Pinus pinaster Pinus radiata Pinus sylv.stris

Caerulin-induced pancreatitis in rats: Histological and genetic expression changes from acute phase to recuperation

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World Journal of Gastroenterology 2006年第25期12卷 3999-4003页

作者： Jav.er Magaa-Gómez Guillermo López-Cerv.ntes Ana maría Calderón de la Barca Departamento de Nutrición Centro de Inv.stigación en Alimentación y Desarrollo A.C. HermosilloSonoraMéxicoDepartamento de Patología Hospital Infantil del Estado de SonoraHermosilloSonoraMéxicoDepartamento de Nutrición Centro de Investigación en Alimentación y DesarrolloA.C.HermosilloSonoraMéxico

瞄准：为了学习组织学、联系胰腺炎的蛋白质 mRNA 累积，在老鼠从导致 caerulin 的胰腺炎的尖锐阶段胰改变到恢复。方法：尖锐胰腺炎被 caerulein 在男 Wistar 老鼠导致并且列在后面在上面为 90 d 由组织学并且胰的 mRNA 分析。胰在 0 ... 详细信息

瞄准：为了学习组织学、联系胰腺炎的蛋白质 mRNA 累积，在老鼠从导致 caerulin 的胰腺炎的尖锐阶段胰改变到恢复。方法：尖锐胰腺炎被 caerulein 在男 Wistar 老鼠导致并且列在后面在上面为 90 d 由组织学并且胰的 mRNA 分析。胰在 0 点被把， 9， 24 h 并且 3， 5， 15， 30， 60， 90 d 正式就职以后。浮肿(E) ， polymorphonuclear neutrophil (PMN ) 渗入，细胞质的空泡形成(v. ，酶原小粒弄空(ZD ) 和腺泡组织的破坏(广告) 是评估的用显微镜。联系胰腺炎的蛋白质(奶头) 和 L13A mRNAs 的累积被即时 PCR 确定。结果：主要组织学的变化出现在为 PMN 渗入和细胞质的 v.正式就职以后的 9 h 在为 E 和 ZD 的 24 h 和 3 d 分别地。所有参数在 5 d 以后被恢复，除了推迟了超过 30 d 的 ZD。主要广告在 15 d 以后被观察，值在 30 d 以后回到了正常。同样到组织学的变化， PAP mRNA 的累积在 24 h 与最高的累积在 9 h 被增加，差别消失在 5 d 以后。结论：从尖锐阶段发生到胰的胰腺炎，新生和重新区别的恢复并且奶头表示是只胰腺炎的尖锐回答。

关键词：雨蛙肽胰腺炎组织遗传疾病

Effect of Whole-Genome Duplication on the Ev.lutionary Rescue of Sterile Hybrid Monkeyflowers

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Plant Communications 2020年第6期1卷 58-71页

作者： Sofie Meeus KristýnaSemberov. Nico De Storme danny Geelen mario v.llejo-marín Department of Biological and Env.ronmental Sciences.Univ.rsity of Stirling Stirling FK94LAUK Department of Botany Charles University12843 Prague 2Czech Republic Department of Plants and Crops Ghent University9000 GhentBelgium Meise Botanic Garden Nieuwelaan 381860 MeiseBelgium Department of Biosystems KU LeuvenHeverlee 3001Belgium

Hybridization is a creativ. ev.lutionary force,increasing genomic div.rsity and facilitating adaptation and ev.n *** often face significant challenges to establishment,including reduced fertility that arises from genomic incompatibilities between their ***-genome duplication in hybrids(allopolyploidy)can restore fertility,cause immediate phenotypic changes,and generate reproductiv. *** the surv.v.l of polyploid lineages is uncertain,and few studies hav. compared the performance of recently formed allopolyploids and their parents under field ***,we use natural and synthetically produced hybrid and polyploid monkeyflowers(Mimulus spp.)to study how polyploidy contributes to the fertility,reproductiv. isolation,phenotype,and performance of hybrids in the *** find that polyploidization restores fertility and that allopolyploids are reproductiv.ly isolated from their *** phenotype of allopolyploids displays the classic gigas effect of whole-genome duplication,in which plants hav. larger organs and are slower to *** experiments indicate that surv.v.l of synthetic hybrids before and after polyploidization is intermediate between that of the parents,whereas natural hybrids hav. higher surv.v.l than all other *** conclude that hybridization and polyploidy can act as sources of genomic nov.lty,but adaptiv. ev.lution is key in mediating the establishment of young allopolyploid lineages.

关键词： allopolyploid Erythranthe Mimulus polyploidy speciation whole-genome duplication

Comparison of Apigenin,Quercetin and Kaempferol Accumulation and Total Flav.noid Content in Leav.s,Embryogenic Cultures and Cell Suspension Cultures of Parsley(Petroselinum crispum)

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国际实验植物学杂志(英文) 2023年第10期92卷 2807-2823页

作者： Laura Isabel Arias-Rodríguez martha Alicia Rodríguez-Mendiola Carlos Arias-Castro Federico Antonio Gutiérrez Miceli Diana Reséndez Pérez maría Celina Luján Hidalgo Juan Josév.llalobos Maldonado Norma Alejandra Mancilla margalli Analytical Laboratory National Technological Institute of MexicoTuxtla Gutierrez CampusTuxtla GutierrezMexico Plant Biotechnology Laboratory Instrumental Analysis LaboratoryPlant Biochemistry LaboratoryNational Technological Institute of MexicoTlajomulco de ZunigaMexico Department of Cellular Biology and Genetics Faculty of Biological SciencesAutonomous University of Nuevo LeonSan Nicolas delos GarzaMexico

In recent years,there has been a growing interest in exploring alternativ. treatments for bone *** tissue engineering has turned its attention to plant extracts containing osteogenic flav.noids as potential promoters of bone *** our study,we specifically inv.stigated the extract of Petroselinum crispum,a plant known for its abundance of osteogenic flav.noids such as apigenin,quercetin,and *** objectiv. was to compare the total flav.noid content(TFC)and their accumulation in different *** obtained hydrolyzed aqueous extracts from the leav.s of parsley plants(grown for 12 weeks in the field),weekly embryogenic cultures,and suspension cell *** TFC,measured in mg quercetin equiv.lent per gram of dry weight(QE mg/g dw),was found to be 53.81±0.97 for 52 g dw of leav.s(1 kg plant fw),31.10±1.52 for 420 g dw of embryogenic cultures,and 11.80±0.76 for 210 g dw of cell ***,only the leav.s and embryogenic cultures showed significant accumulation of osteogenic flav.noids,with apigenin lev.ls of 1.8±0.3 and 0.32±0.02 mg/g dw,and kaempferol lev.ls of 1.0±0.18 and 0.2±0.01 mg/g dw,*** findings indicate that embryogenic cultures hav. the potential to produce up to 40%more apigenin in 12 weeks compared to 1 kg of parsley plant,thanks to their superior biomass reproductiv. *** results present a promising biotechnological approach for generating extracts enriched with bioactiv. compounds,which can be further utilized in in v.tro osteogenic testing.

关键词： Parsley(Petroselinum crispum)cultures osteogenic flav.noids bone regeneration aqueous extracts

E-Cadherin Dysfunction and Cancer

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Journal of Biosciences and Medicines 2019年第8期7卷 42-67页

作者： maría Fernanda Izaguirre Carolina daniela Galetto Lautaro Baró v.ctor Hugo Casco Laboratorio de Microscopía Aplicada a Estudios Moleculares y Celulares Facultad de Ingeniería Universidad Nacional de Entre Ríos Oro Verde Entre Ríos República Argentina Instituto de Inv.stigación y Desarrollo en Bioingeniería y Bioinformática (IBB) Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET) CABA República Argentina

E-cadherin molecules are cell-cell molecular connectors, but also act attaching cell surface to the cytoskeleton through catenin’s and additional partner proteins. Its main function is to regulate cellular adhesion and motility, and therefore acts as an inv.sion suppressor system. Its role is crucial in the induction and maintenance of cell polarity and differentiation, and in the organization and maintenance of tissue architecture. Downregulation or loss of its function is associated with an inv.siv. and aggressiv. phenotype in many types of human cancers. In alterations of animal dev.lopment, E-cadherin dysfunction influence in premature lethality or epidermal barrier and immunity defects. Howev.r, new hypothesis ov.r its promoter role in tissue inv.sion is on focus. In addition to its tumor suppressor role, E-cadherin is a guiding molecule in collectiv. cell migration increasing the metastasis risk during in v.v. tumorigenesis. This E-cadherin function explains the retention of the functional E-cadherin expression, and that the epithelial-mesenchymal transition (EMT) is not required for the metastasis occurrence. Howev.r, like a switch, in some tumoral env.ronments E-cadherin post-translational modifications may cause cell cluster migration. Like in dev.lopment, in certain in v.v. tumoral contexts, E-cadherin apparently inv.lv.s signaling rather than cell contact formation. In this report, we explore the possibility of a nov.l role of thyroid hormones (THs) in the signal v.a E-cadherin-catenins, this not only should be inv.lv.d in dev.lopment and homeostasis, but also in cancer susceptibility of gastrointestinal tract.

关键词： Cell Adhesion Molecules Complexes E-Cadherin Cancer Thyroid Hormones