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Influence of dissolved organic matter character on mercury incorporation by planktonic organisms: An experimental study using oligotrophic water from Patagonian lakes

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Journal of Environmental Sciences 2013年第10期25卷 1980-1991页

作者： María C.Diéguez Claudia P.Queimalios Sergio Ribeiro Guevara Mark Marvin-DiPasquale Carolina Soto Crdenas María A.Arribre laboratorio de Fotobiología INIBIOMA CONICET-UNComahue laboratorio de Fotobiolog INIBIOMA CONICET-UNComahue laboratorio de Anlisis por Activación Neutrónica Centro Atómico Bariloche CNEA United States Geological Survey laboratorio de Anlisis por Activacio Neutrónica Centro Atómico Bariloche CNEA

Ligands present in dissolved organic matter （DOM） form complexes with inorganic divalent mercury （Hg^2＋） affecting its bioavailability in pelagic food webs. This investigation addresses the influence of a natural gradient of DOM present in Patagonian lakes on the bioaccumulation of Hg^2＋（the prevailing mercury species in the water column of these lakes） by the algae Cryptomonas erosa and the zooplankters Brachionus calyciflorus and Boeckella antiqua. Hg^2＋ accumulation was studied through laboratory experiments using natural water of four oligotrophic Patagonian lakes amended with^197Hg^2＋. The bioavailability of Hg^2＋ was affected by the concentration and character of DOM. The entrance of Hg^2＋ into pelagic food webs occurs mostly through passive and active accumulation. The incorporation of Hg^2＋ by Cryptomonas, up to 27% of the Hg^2＋ amended, was found to be rapid and dominated by passive adsorption, and was greatest when low molecular weight compounds with protein-like or small phenolic signatures prevailed in the DOM. Conversely, high molecular weight compounds with a humic or fulvic signature kept Hg^2＋ in the dissolved phase, resulting in the lowest Hg^2＋ accumulation in this algae. In Brachionus and Boeckella the direct incorporation of Hg from the aqueous phase was up to 3% of the Hg^2＋ amended. The dietary incorporation of Hg^2＋ by Boeckella exceeded the direct absorption of this metal in natural water, and was remarkably similar to the Hg^2＋ adsorbed in their prey. Overall, DOM concentration and character affected the adsorption of Hg^2＋ by algae through competitive binding, while the incorporation of Hg^2＋ into the zooplankton was dominated by trophic or dietary transfer.

关键词： mercury dissolved organic matter plankton mercury incorporation Patagonian lakes Argentina

Transmission FTIR derivative spectroscopy for estimation of furosemide in raw material and tablet dosage form

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Acta Pharmaceutica Sinica B 2014年第5期4卷 376-383页

作者： Máximo Gallignani Rebeca A.Rondón JoséF.Ovalles María R.Brunetto laboratorio de Espectroscopia Molecular Departamento de QuímicaFacultad de CienciasUniversidad de Los AndesMérida 5101-AVenezuela departamento de Análisis y Control Facultad de Farmacia y BioanálisisUniversidad de Los AndesMérida 5101-AVenezuela

A Fourier transform infrared derivative spectroscopy(FTIR-DS)method has been developed for determining furosemide(FUR)in pharmaceutical solid dosage *** method involves the extraction of FUR from tablets with N,N-dimethylformamide by sonication and direct measurement in liquid phase mode using a reduced path length *** general,the spectra were measured in transmission mode and the equipment was configured to collect a spectrum at 4 cm^(-1) resolution and a 13 s collection time(10 scans co-added).The spectra were collected between 1400 cm^(-1) and 450 cm^(-1).derivative spectroscopy was used for data processing and quantitative measurement using the peak area of the second order spectrum of the major spectral band found at 1165 cm^(-1)(SO_(2) stretching of FUR)with baseline *** method fulfilled most validation requirements in the 2 mg/mL and 20 mg/mL range,with a 0.9998 coefficient of determination obtained by simple calibration model,and a general coefficient of variation y for the proposed assay method resulted within the(100±3)%over the 80%–120% range of the target *** results agree with a pharmacopoeial method and,therefore,could be considered interchangeable.

关键词： FTIR derivative spectroscopy Furosemide Frusemide Pharmaceutical analysis

Home range variability,spatial aggregation,and excursions of Akodon azarae and Oligoryzomys flavescens in Pampean agroecosystems

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Integrative Zoology 2020年第5期15卷 401-415页

作者： Irene GOROSITO Ailén BENÍTEZ Maria BUSCH laboratorio de Ecología de PoblacionesFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos Airesand Instituto de EcologíaGenética y Evolución de Buenos AiresConsejo Nacional de Investigaciones Científicas y TécnicasBuenos AiresArgentina laboratorio de Ecología de Poblaciones Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresBuenos AiresArgentina laboratorio de Ecología de Poblaciones Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos Airesand Instituto de EcologíaGenética y Evolución de Buenos AiresConsejo Nacional de Investigaciones Científicas y TécnicasBuenos AiresArgentina

Rodents are reservoirs of various types of hantavirus,some of which are agents of hantavirus pulmonary syndrome in *** hantavirus is associated with a single rodent host species but successive spill-over events may eventually lead to host-switching and new species’becoming host of a given *** study aims to gain an understanding of the spatial ecology of two hantavirus-host species,Akodon azarae,and Oligoryzomys flavescens,by identifying factors modulating their home range sizes and stability,and by evaluating intra-and interspecific spatial aggregation for these species and a third one—Oxymycterus rufus—living in *** this,eleven capture-mark-recapture surveys were carried out,spanning 22 *** found that *** males have larger and more mobile home ranges than females,independently of the ***,males could likely have a more relevant role in the transmission of hantavirus because of their greater exposure both to a higher number of contacts between individuals and viral contamination of the ***,*** individuals showed negligible displacements of their home range through time,which could limit the range of hantavirus spread in host *** *** is host to Lechiguanas hantavirus(pathogenic to humans)this result encompasses epidemiological relevance,for it may imply the existence of local foci of ***,individuals of both species performed excursions outside their home *** events could enable hantavirus spread over distances beyond the normal range of movements and lead to new hantavirus outbreaks in formerly non-infected rodent populations,favoring the persistence of the virus in nature.

关键词： hantavirus home range intra-and interspecific contact rodent spatial ecology

Apomorphine effects on the hippocampus

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Neural Regeneration Research 2018年第12期13卷 2064-2066页

作者： Luis Enrique Arroyo-García Antonio Rodríguez-Moreno Gonzalo Flores laboratorio de Neuropsiquiatria Instituto de Fisiologia Benemerita Universidad Autenoma de Puebla Puebla Mexico laboratorio de Neurociencia Celular y Plasticidad Universidad Pablo de Olavide Sevilla Spain

Apomorphine is a non-specific dopamine receptor agonist that has been used in the treatment of some diseases and mental disorders. Its use has particularly well documented in Parkinson＇s disease（PD）. The dopaminergic agonists like apomorphine are related to oxidative processes that could induce cell damage and the functional impairment of some structures in the brain. However, most information about apomorphine in literature is focused on the improvement of the motor problems characteristic of PD, but little is known about the effects on cognitive behaviors and brain structures indirectly related to motor function. The presence of dopaminergic receptors in the hippocampus has recently been discovered, in connection with cognitive behaviors like learning and memory, these receptors are needed in neuronal plasticity. There has been a growing interest to know if this structure could be compromised by the effect of apomorphine and elucidate if part of the cognitive impairment present in the PD is due to the effect of apomorphine. In this mini-review, we summarized how apomorphine has been used since its creation, we discuss the latest information about its effect on the hippocampus and also the future perspectives to fully understand the effects of this compound.

关键词： dopamine receptor apomorphine hippocampus learning and memory plasticity dendritic length oxidative stress Parkinson's disease

Reagent-free determination of amikacin content in amikacin sulfate injections by FTIR derivative spectroscopy in a continuous flow system

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Journal of Pharmaceutical Analysis 2014年第2期4卷 125-131页

作者： José F.Ovalles Máximo Gallignani María R.Brunetto Rebeca A.Rondón Carlos Ayala departamento de Análisis y Control Facultad de Farmacia y BioanálisisUniversidad de Los AndesMérida 5101AVenezuela laboratorio de Espectroscopia Molecular Departamento de QuímicaFacultad de CienciasUniversidad de Los AndesMérida 5101AVenezuela

The quantitative estimation of amikacin （AMK） in AMK sulfate injection samples is reported using FTIR-derivative spectrometric method in a continuous flow system. Fourier transform of mid-IR spectra were recorded without any sample pretreatment. A good linear calibration （r40.999, %RSDo 2.0） in the range of 7.7-77.0 mg/mL was found. The results showed a good correlation with the manufacturer＇s and overall they all fell within acceptable limits of most pharmacopoeial monographs on AMK sulfate.

关键词： Amikacin FlrIR derivative spectro-metry Continuous flow system Pharmaceuticalpreparation Injection Sulfate

Contrasting levels of genotype by environment interaction for life history and morphological traits in invasive populations of Zaprionus indianus(Diptera:Drosophilidae)

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Insect Science 2020年第5期27卷 1090-1100页

作者： Nicolas J.Lavagnino Marcos Imberti Victoria E.Ortizj Nicolas Flaibani Juan Jose Fanara laboratorio de Evolucion Departamento de EcologiaGenetica y EvolucidnFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresArgentina IEGEBA-CONICET Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresArgentina

It has been demonstrated that phenotypic plasticity and genotype by envi-ronment interaction are important for coping with new and heterogeneous environments during *** indianus Gupta(Diptera:Drosophilidae)is an Afrotropical invasive fly species introduced to the South American continent in *** species is generalist and polyphagous,since it develops and feeds in several different fruit *** characteristics of *** suggest that phenotypic plasticity and genotype by environment interaction may be important in this species invasion *** this sense,our aim was to investigate the role of genetic variation for phenotypic plasticity(geno-type by environment interaction)in *** invasion of the South American ***,we quantified quantitative genetic variation and genotype by environment in-teractions of morphological and life history traits in different developmental environments,that is,host *** was done in different populations in the invasive range of ***-anus in *** showed that *** populations have considerable amounts of quantitative genetic ***,genotype by environment interactions was detected for the different traits analyzed in response to the different developmental ***,the amounts and patterns of these parameters differed between *** interpreled these results as the existence of diferences in evolutionary potential be-tween populations that have an important role in the short-and long-term success of the *** invasion process.

关键词： biological invasion genotype by env ironment interaction invaded range life history traits morphological traits Zaprionus indianus

The short form of the SUR1 and its functional implications in the damaged brain

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Neural Regeneration Research 2022年第3期17卷 488-496页

作者： Iván Alquisiras-Burgos Javier Franco-Pérez Moisés Rubio-Osornio Penélope Aguilera laboratorio de Patología Vascular Cerebral Instituto Nacional de Neurología y Neurocirugía“Manuel Velasco Suárez”CDMXMexico laboratorio de Formación Reticular Instituto Nacional de Neurología y Neurocirugía“Manuel Velasco Suárez”CDMXMexico laboratorio Experimental de Enfermedades Neurodegenerativas Instituto Nacional de Neurología y Neurocirugía“Manuel Velasco Suárez”CDMXMexico.

Sulfonylurea receptor(SUR) belongs to the adenosine 5′-triphosphate(ATP)-binding cassette(ABC) transporter family;however,SUR is associated with ion channels and acts as a regulatory subunit determining the opening or closing of the ***8 and Abcc9 genes code for the proteins SUR1 and SUR2,*** SUR1 transcript encodes a protein of 1582 amino acids with a mass around 140–177 k Da expressed in the pancreas,brain,heart,and other *** is well known that SUR1 assembles with Kir6.2 and TRPM4 to establish K_(ATP) channels and non-selective cation channels,***8 and 9 are alternatively spliced,and the resulting transcripts encode different isoforms of SUR1 and SUR2,which have been detected by different experimental ***,the use of binding assays to sulfonylureas and Western blotting has allowed the detection of shorter forms of SUR(-65 k Da).Identity of the SUR1 variants has not been clarified,and some authors have suggested that the shorter forms are ***,immunoprecipitation assays have shown that SUR2 short forms are part of a functional channel even coexisting with the typical forms of the receptor in the *** evidence confirms that the structure of the short forms of the SURs is fully functional and does not lose the ability to interact with the *** structural changes in short forms of SUR modify its affinity to ATP,regulation of its expression might represent an advantage in pathologies where ATP concentrations decrease and a therapeutic target to induce ***,the expression of SUR1 variants might be induced by conditions associated to the decrease of energetic substrates in the brain(*** stroke and epilepsy).In this review,we want to contribute to the knowledge of SUR1 complexity by analyzing evidence that shows the existence of short SUR1 variants and its possible implications in brain function.

关键词： brain edema epilepsy Parkinson's disease stroke sulfonylurea receptor 1 SUR1 traumatic brain injury TRPM4

Environmental drivers of long-term variations in the abundance of the red hocicudo mouse (Oxymycterus rufus) in Pampas agroecosystems

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Integrative Zoology 2024年第1期19卷 37-51页

作者： Laura Mariel CALFAyAN Regino CAVIA Jimena FRASCHINA Juan Santiago GUIDOBONO Irene Laura GOROSITO María BUSCH laboratorio de Ecología de Poblaciones Departamento de EcologíaGenética y EvoluciónFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos Aires and Instituto de EcologíaGenética y Evolución de Buenos Aires(IEGEBA)Buenos AiresArgentina

During the 20th century,there has been an ongoing agricultural expansion and global warming,two of the main determinants influencing biodiversity changes in *** red hocicudo mouse(Oxymycterus rufus)inhabits subtropical grasslands and riparian habitats and has increased its abundance in recent years in central Argentina *** paper describes the long-term temporal changes in *** abundance in Exaltación de la Cruz department,Buenos Aires province,Argentina,in relation to weatherfluctuations and landscape features,as well as analyzes the spatio-temporal structure of captures of *** used generalized liner models,semi-variograms,the Mantel test,and autocorrelation functions for the analysis of rodent data obtained from trappings conducted between 1984 and *** showed an increase in abundance across the years of study,with its distribution depending on landscape features,such as habitat types and the distance *** rates showed a spatio-temporal aggregation,suggesting expansion from previously occupied *** was more abundant at lower minimum temperatures in summer,higher precipitation in spring and summer,and lower precip-itations in *** conditions affected *** abundance,but there was local variation that differed from global patterns of climate change.

关键词： agroecosystems climate change linear habitats Oxymycterus rufus rodent

Progesterone for the treatment of central nervous system disorders: the many signaling roads for a single molecule

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Neural Regeneration Research 2020年第10期15卷 1846-1847页

作者： Susana Laura González Universidad de Buenos Aires Facultad de Medicina Departamento de Bioquímica Humana Buenos Aires laboratorio de Nocicepción y Dolor Neuropático Instituto de Biología y Medicina Experimental

Central nervous system(CNS)injuries and neurodegenerative diseases show a broad spectrum of common pathophysiological processes,including oxidative stress,neuroinflammation,excitotoxicity,demyelination and neurotransmission *** the past decades,valuable experimental investigations have helped to clarify the role and timing of these multiple molecular and cellular mechanisms in each of these particular disorders,which usually overlap and critically contribute to long-term ***,up to now,no definite cures or effective disease-modifying therapies are available for any of these *** has led to an active search of novel therapeutic approaches,including the repositioning of existing drugs for new indications,as a valid approach to promptly move candidate molecules to clinical trials.

关键词： injuries disorders drugs