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Antiprotozoal Activity of a <i>Thymus vulgaris</i>Methanol Extract and Its Fractions

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Health 2017年第7期9卷 1081-1094页

作者： Jesús Norberto Garza-gonzález Javier Vargas-Villarreal Ma Julia Verde-Star Catalina Rivas-Morales Azucena Oranday-Cárdenas Magda E. Hernandez-García laura De La Garza-Salinas Francisco gonzález-Salazar Department of Chemistry Phytochemistry and Analytical Chemistry Lab Faculty of Biological Sciences University Autonomous of Nuevo Leon San Nicolas de los Garza Mexico Department of Basic Sciences Division of Health Sciences University of Monterrey San Pedro Garza Garcia Mexico Laboratory of Biochemistry and Cell Physiology Division of Cellular and Molecular Biology Center for Biomedical Research of the Northeast Mexican Social Security Institute Monterrey Mexico Mexican Social Security Institute Nuevo Leon Delegation Monterrey Mexico

Introduction: Thymus vulgaris is used in traditional medicine to treat gastrointestinal diseases because of its antifungal, antibacterial, and antispasmodic activity. Objective: To verify whether Thymus vulgaris also has antiprotozoal activity against Trichomonas vaginalis, Giardia lamblia and Entamoeba histolytica trophozoites. Materials and methods: Conventional cultures of parasites were measured on the third day during the logarithmic growth phase. The antiprotozoal activity of the methanol extract and its fractions were evaluated comparing growth in cultures with and without extracts. Next, the extract was fractionated by polarity-based partitioning. Then, the purity of each fraction was determined by thin layer chromatography (TLC). The percentage of growth inhibition was calculated with respect to untreated controls. The 50% inhibitory concentration (IC50) of each extract was calculated by PROBIT analysis. Results: We found that a methanol extract of the aerial parts of Thymus vulgaris, at 300 μg/mL, inhibited the in vitro growth of G. lamblia and T. vaginalis, while E. histolytica growth was poorly inhibited. The methanol extract was further separated into mixtures of ursolic, oleanolic, and betulinic acids. The IC50 values of ursolic acid against G. lamblia and T. vaginalis were 8.12 μg/mL and 5.51 μg/mL, respectively. Conclusions: The methanol extract fraction containing ursolic acid obtained from Thymus vulgaris has antiprotozoal activity against G. lamblia and T. vaginalis trophozoites.

关键词： Thymus vulgaris Trichomonas vaginalis Giardia lamblia Entamoeba histolytica Antiprotozoal Agents

The Phenols of the Genus <i>Agave</i>(Agavaceae)

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Journal of Biomaterials and Nanobiotechnology 2013年第3期4卷 9-16页

作者： Norma Almaraz-Abarca Eli Amanda Delgado-Alvarado José Antonio ávila-Reyes José Natividad Uribe-Soto laura Silvia gonzález-Valdez Centro Interdisciplinario de Investigación para el Desarrollo Integral Regional Unidad Durango Instituto Politécnico Nacional Durango Dgo México

A review is presented about the studies that have been carried out on the phenolic composition of the species of the genus Agave in order to show which species of the genus has been analyzed, what is the potential of the species of Agave as source of phenolics with important biological activities, and what is the significance of the phenolic profiles as chemotaxonomic markers in the genus. The results of the analysis of a dozen of Agave species reveal an important richness of phenolic compounds, including flavonoids, homoisoflavonoids, and phenolic acids, and a broad diversity of biological activities associated to those compounds, as antioxidant, antibacterial, antifungal, antinematod, and immunomodulatory capabilities. The phenols of Agave also have a major potential as specific chemotaxonomic markers.

关键词： Genus Agave Phenol Profiles Homoisoflavanoids Biological Activity Chemotaxonomic Markers

Land-use change and windstorms legacies drove the recolonization dynamics of laurel forests in Tenerife, Canary islands

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Forest Ecosystems 2023年第1期10卷 113-124页

作者： Vicente Rozas Maria A.Garcia-Lopez Jose M.Olano Gabriel Sanguesa-Barreda Miguel Garcia-Hidalgo Susana Gomez-gonzalez Roberto Lopez-Rubio Jose M.Fernandez-Palacios Ignacio Garcia-gonzalez laura Lozano-Lopez Paula Garcia-gonzalez Ana I.Garcia-Cervigon EiFAB-iuFOR Universidad de ValladolidCampus Duques de Soria42004SoriaSpain Departamento de Biologia-IVAGRO Universidad de CadizCampus Rio San Pedro11510Puerto RealSpain Center for Climate and Resilience Research(CR)2 Blanco Encalada 20028370449SantiagoChile Area de Biodiversidad y Conservacion Universidad Rey Juan Carlosc/Tulipan s/n28933MostolesSpain Grupo de Ecologia y Biogeografia Insular Universidad de La Laguna38206La LagunaTenerifeSpain BIOAPLIC Departamento de BotanicaEscola Politecnica Superior de EnxenariaCampus TerraUniversidade de Santiago de CompostelaLugo27002Spain

Laurel forests are quite relevant for biodiversity conservation and are among the island ecosystems most severely damaged by human *** the past,Canary laurel forests have been greatly altered by logging,livestock and *** remains of laurel forests are currently protected in the Canary Islands(Spain).However,we miss basic information needed for their restoration and adaptive management,such as tree longevity,growth potential and responsiveness to natural and anthropogenic *** dendrochronological methods,we studied how forest dynamic is related to land-use change and windstorms in two well-preserved laurel forests on Tenerife *** cores were collected from over 80 trees per stand at three stands per *** used ring-width series to estimate tree ages and calculate annual basal area increments(BAI),cumulative diameter increases,and changes indicative of released and suppressed *** tree species were found in all stands,with Laurus novocanariensis,Ilex canariensis and Morella faya being the most common *** some individuals were over 100 years old,61.8%-88.9% of the trees per stand established between 1940 and 1970,coinciding with a post-war period of land abandonment,rural exodus and the onset of a tourism *** trees have shown growth rates larger than 1 cm diameter per year and most species have had increasing BAI trends over the past *** growth releases occurred after windstorms at both sites,but the effects of windstorms were site-dependent,with the 1958 storm affecting mainly the eastern tip of the island(Anaga massif)and the 1991 storm the western tip(Teno massif).Given the great ability of laurel forest trees to establish after land use cessation and to increase growth after local disturbances such as windstorms,passive restoration may be sufficient to regenerate this habitat in currently degraded areas.

关键词： Canary islands Dendroecology Disturbance Forest structure Macaronesia Management cessation Tree rings

Novel Galectin-3 interactions involved in oligodendroglial differentiation make inroads into therapeutic strategies for demyelinating diseases

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Neural Regeneration Research 2021年第2期16卷 289-290页

作者： laura Andrea Pasquini Department of Biological Chemistry School of Pharmacy and BiochemistryInstitute of Biological Chemistry and Physicochemistry(IQUIFIB)University of Buenos Aires and National Research Council(CONICET)Buenos AiresArgentina

Galectins(Gals)constitute a 15-member class ofβ-galactoside-binding lectins which recognize *** lacking specific receptors,Gals form multivalent complexes with cell surface glycoconjugates containing suitable oligosaccharides and thus trigger intracellular signals to regulate cell survival and *** are classified into three groups on the basis of their structural architecture:proto,chimera and tandem types。

关键词： spite complexes strategies

Variability in the Light Absorption Coefficient by Phytoplankton,Non-Algal Particles and Colored Dissolved Organic Matter in the Northern Gulf of California

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Open Journal of Marine Science 2018年第1期8卷 20-37页

作者： Stella P.Betancur-Turizo Adriana G.gonzález-Silvera Eduardo Santamaría-Del-Angel Roberto Millán-Núnez Eduardo Millán-Núnez Héctor García-Nava Víctor M.Godínez laura Sánchez-velasco Facultad de Ciencias Marinas Universidad Autonoma de Baja CaliforniaEnsenadaMéxico Grupo de Investigacion en Oceanología Facultad de Oceanografía FísicaEscuela Naval de Cadetes“Almirante Padilla”Barrio BosqueSector ManzanilloCartagena de IndiasColombia Departamento de Ecología Marina CICESEEnsenadaMéxico Instituto de Investigaciones Oceanológicas Universidad Autónoma de Baja CaliforniaEnsenadaMéxico Departamento de Oceanografía Física CICESEEnsenadaMéxico Departamento de Plancton y Ecología Marina CICIMAR-IPN.Av.Instituto Politécnico Nacional s/nLa PazMéxico

Variability of the optical properties of the northern Gulf of California (México) were analyzed for the first time based on six cruises performed from spring to summer (March to September) between 2008 and 2013. The changes observed in the absorption by three seawater components (phytoplankton, detritus and chromophoric dissolved organic matter or CDOM) were analyzed in relation to changes in bio-optical regions and composition of the phytoplankton community (determined based on phytoplankton pigments). Two regions with unique bio-optical characteristics were identified separated by a narrow transition zone: the Upper Gulf of California (UGC) and Northern Gulf of California (NGC). Despite the temporal changes in their spatial distribution they maintained particular characteristic. UGC is characterized by an average Chla of 1.78 mg/m3, the dominance of microphytoplankton (diatoms and dinoflagellates) and a stronger contribution of detritus to total light absorption. NGC is characterized by an average Chla of 0.7 mg/m3 and the predominance of picophytoplankton, characterized by the dominance of zeaxanthin (marker pigment for cyanobacteria) and/or chlorophyll b (marker pigment for green algae), along with a co-dominium by CDOM and phytoplankton to light absorption. Results indicate that Case II waters can be very different when evaluating the individual contribution by phytoplankton, detritus and CDOM to total light absorption what has to be considered for the selection of bio-optical models for each specific region what can also help to a better definition of the related uncertainties.

关键词： Light Absorption Phytoplankton CDOM Detritus Ocean Color Gulf of California

Some Univalence Conditions for a General Integral Operator

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Chinese Annals of Mathematics,Series B 2012年第6期33卷 801-806页

作者： laura STANCIU Daniel BREAZ Department of Mathematics University of Pitesti Department of Mathematics University of Alba Iulia

The authors consider the classes of the univalent functions denoted by SH(β),SP and SP(α,β).On these classes,the univalence conditions for a general integral operator are studied.

关键词： Analytic function Integral operator Univalence condition GeneralSchwarz lemma

Hierarchical state-abstracted and socially augmented Q-Learning for reducing complexity in agent-based learning

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控制理论与应用（英文版） 2011年第3期9卷 440-450页

作者： laura RAY Thayer School of Engineering Dartmouth College

A primary challenge of agent-based policy learning in complex and uncertain environments is escalating computational complexity with the size of the task space(action choices and world states) and the number of ***,there is ample evidence in the natural world that high-functioning social mammals learn to solve complex problems with ease,both individually and *** ability to solve computationally intractable problems stems from both brain circuits for hierarchical representation of state and action spaces and learned policies as well as constraints imposed by social *** biologically derived mechanisms for state representation and mammalian social intelligence,we constrain state-action choices in reinforcement learning in order to improve learning *** results bound the reduction in computational complexity due to stateion,hierarchical representation,and socially constrained action selection in agent-based learning problems that can be described as variants of Markov decision *** of two task domains,single-robot herding and multirobot foraging,shows that theoretical bounds hold and that acceptable policies emerge,which reduce task completion time,computational cost,and/or memory resources compared to learning without hierarchical representations and with no social knowledge.

关键词： Decentralized Markov decision process Reinforcement learning Multiagent systems

Clinical Parameters in the First 5 Minutes after Birth Have a Predictive Value for Survival of Extremely Preterm Infants

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Maternal-Fetal Medicine 2023年第4期5卷 244-247页

作者： laura Torrejón-Rodríguez Álvaro Solaz-García Inmaculada Lara-Cantón Alejandro Pinilla-gonzález Marta Aguar Máximo Vento Division of Neonatology University and Polytechnic Hospital La Fe(HULAFE)Valencia 46026Spain Neonatal Research Group Instituto de Investigación Sanitaria La Fe(IISLAFE)Valencia 46026Spain

Extreme preterm infants(60%)and lower(<30%)initial FiO_(2).Recent evidence and meta-analyses have underscored the predictive value for survival and/or relevant clinical outcomes of the Apgar score and the achievement of arterial oxygen saturation measured by pulse oximetry≥85%at 5 minutes after *** clinical trials comparing higher versus lower initial FiO_(2)have been launched aiming to optimize postnatal stabilization of extreme preterm while avoiding adverse effects of hypoxemia or hyperoxemia.

关键词： Extreme preterm Postnatal stabilization Oxygen saturation Heart rate Inspired fraction of oxygen Apgar score

Genetic predisposition to colorectal cancer:Where we stand and future perspectives

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World Journal of Gastroenterology 2014年第29期20卷 9828-9849页

作者： laura Valle Hereditary Cancer Program Catalan Institute of OncologyIDIBELL08908 BarcelonaSpain

The development of colorectal cancer(CRC)can be influenced by genetic factors in both familial cases and sporadic *** CRC has been associated with genetic changes in high-,moderate-and low-penetrance susceptibility ***,despite the availability of current gene-identification techniques,the genetic causes of a considerable proportion of hereditary cases remain ***-wide association studies of CRC have identified a number of common lowpenetrance alleles associated with a slightly increased or decreased risk of *** accumulation of low-risk variants may partly explain the familial risk of CRC,and some of these variants may modify the risk of cancer in patients with mutations in high-penetrance *** the predisposition to develop CRC will require investigators to address the following challenges:the identification of genes that cause uncharacterized hereditary cases of CRC such as familial CRC type X and serrated polyposis;the classification of variants of unknown significance in known CRC-predisposing genes;and the identification of additional cancer risk modifiers that can be used to perform risk assessments for individual mutation *** performed a comprehensive review of the genetically characterized and uncharacterized hereditary CRC syndromes and of lowand moderate-penetrance loci and variants identified through genome-wide association studies and candidate-gene *** challenges and future perspectives in the field of CRC predisposition are also discussed.

关键词： Hereditary colorectal cancer Familial colorectal cancer High penetrance Low penetrance Cancer syndromes Cancer susceptibility Hereditary cancer genes Risk variants Heritability