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Papers by veronica Nuñez

Research paper thumbnail of Adverse Effects in Patients with Intellectual and Developmental Disabilities Hospitalized at the University Clinical Hospital

Journal of Personalized Medicine

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Research paper thumbnail of Synthesis, biological and structural characterization of novel glycopeptide analogs of nociceptin

Research paper thumbnail of Incidence of Neonatal Abstinence Syndrome (NAS) in Castilla y Leon (Spain)

Children, 2021

Introduction: Neonatal Abstinence Syndrome (NAS) is considered a Public Health problem that is de... more Introduction: Neonatal Abstinence Syndrome (NAS) is considered a Public Health problem that is defined as a group of symptoms that appear in the newborn due to withdrawal from intrauterine drug exposure. Objective: The aim of this study was to analyze the incidence of NAS in Castilla y León from 2000 to 2019. Methodology: Data of NAS cases in Castilla y León from 2000 to 2019 were obtained. NAS incidence per 1000 births was calculated and the correlation among data from different provinces and years was analyzed. Results: The cumulative incidence of NAS in Castilla y León per 1000 births between 2000-2019 was 0.91‰, with great interprovincial variability. The provinces of Zamora and Palencia stand out, with high incidence rates of NAS despite their low birth rates. The temporal trend points towards a decrease in incidence from 2000 to 2019. Opioids such as methadone, cannabis, benzodiazepines and poly-drug use are the most prevalent drugs causing NAS, and it has also been observed t...

Research paper thumbnail of Cultural Appreciation or Cultural Appropriation

Bloomsbury Fashion Business Cases, 2018

Research paper thumbnail of Aportacion al estudio de los mecanismos de transduccion de la señal de los receptores opioides. (aplicacion a los problemas del dolor y de la tolerancia y dependencia a drogas opiaceas)

En este trabajo se han estudiado algunos de los mecanismos bioquimicos responsables de la activid... more En este trabajo se han estudiado algunos de los mecanismos bioquimicos responsables de la actividad de los agentes opiaceos, utilizando el pez cebra como modelo experimental. Primeramente hemos clonado y caracterizado la pronociceptina y prodinorfina de pez cebra, encontrando en estos precursores nuevas secuencias para peptidos opioides. Seguidamente hemos caracterizado farmacologicamente el peptido Met-encefalina-Gly-Tyr, demostrando que se une a receptores opioides de pez cebra y mamifero, pudiendo actuar como ligando endogeno de los receptores ZFOR1 y ZFOR4. Asimismo, la dinorfina A de pez cebra se une a todos los receptores opioides de pez cebra. El estudio de la internalizacion del receptor ZFOR4 ha demostrado que este receptor es internalizado por la etorfina y por peptidos endogenos, presentando diferencias en la dosis efectiva media, pero no en la cinetica. El receptor ZFOR3 solo es internalizado por la dinorfina A o por la dinorfina 1-13, con una cinetica y dosis efectiva m...

Research paper thumbnail of Checklist of the nematode parasites of wild birds of Argentina

Revue suisse de Zoologie, 2020

BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access t... more BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.

Research paper thumbnail of Revisión de dos especies de Physidae

Revista Mexicana de Biodiversidad, 2011

Resumen. A pesar de los numerosos trabajos que abordan desde diferentes ópticas la sistemática de... more Resumen. A pesar de los numerosos trabajos que abordan desde diferentes ópticas la sistemática de Physidae, la situación taxonómica de las entidades de esta familia presentes en la Argentina es aún confusa. Por lo tanto, se abordó el estudio de las 2 especies de hallazgo más frecuente en el país, realizando una actualización de la descripción de las mismas para confirmar su estatus taxonómico y facilitar su correcta identificación. Se analizaron ejemplares de 5 localidades diferentes de cada especie. Para la redescripción se analizaron fundamentalmente caracteres de la conchilla, morfología externa, rádula y reproductor. Las diferencias inter-específicas de las características de las conchillas y de las partes blandas fueron analizadas estadísticamente por separado, mediante análisis de los componentes principales y factorial discriminante. Los caracteres observados permitieron concluir que la correcta denominación de las especies aquí estudiadas es Stenophysa marmorata (Guilding, 1828) y Physa acuta Draparnaud, 1805. Si bien existen diferencias conquiológicas entre estas 2 especies, queda demostrado que es importante la observación de las partes blandas para una correcta determinación.

Research paper thumbnail of Desarrollo De Competencias Investigativas en Los Institutos Tecnológicos

Revista de Investigación , Formación y Desarrollo: generando productividad institucional., 2017

Las Instituciones de la Educación Superior son reconocidas cada vez más como un instrumento de de... more Las Instituciones de la Educación Superior son reconocidas cada vez más como un instrumento de desarrollo y están consideradas como factor clave para incrementar la competitividad y la calidad de vida de los ciudadanos, el desafío que se les presenta es considerable si se tiene en cuenta que se deben de enfrentar a una realidad en la cual los procesos de aprendizaje están en transformación constante exigiéndoles cada día más. Una de las principales transformaciones de las instituciones de educación superior se fundamenta en la generación de ciencia y tecnología suficiente revelando a través de ella el desarrollo que toda institución de educación superior tie - ne que obtener. Las competencias investigativas son un eje esencial en el desarrollo del aprendizaje organizacional de toda institución de educación superior transformándose en un aspecto esencial revelando que tan pertinente es la educación que se brinda tomando en consideración a la sociedad

Research paper thumbnail of Figure 28 from: Núñez V, Damborenea C, Darrigran G (2019) Illustrated catalogue of type specimens of Volutidae (Gastropoda) in the Malacological Collection of the Museo de La Plata, Argentina. Zoosystematics and Evolution 95(1): 65-93. https://doi.org/10.3897/zse.95.30541

The Malacology Collection of the Museo de La Plata contains more 13,000 lots from various regions... more The Malacology Collection of the Museo de La Plata contains more 13,000 lots from various regions of Argentina and other South American countries. The Collection also includes 511 type lots. Among the oldest type specimens are a large series of marine gastropod from Patagonia which were studied by Fernando Lahille in 1895. He was one of the first's naturalists of the Museo de La Plata, and there between 1893 and 1899, he made several studies in zoology. During that time, he described three species and forty varieties of Volutidae. Herein, we compare Lahille's type specimens, label data, number, and specimen information to the original descriptions and illustrations of these taxa. Each taxon has been photographed in multiple views. This historic type material is entirely composed of shells. This work is the first of a series of photographic catalogues of type material from the Malacology Collection of the Invertebrate Division of Museo de La Plata.

Research paper thumbnail of Nematode parasites of the Chilean Flamingo, Phoenicopterus chilensis (Phoenicopteridae) from Central Argentina, with a description of a new species of Tetrameres (Tetrameridae)

Acta parasitologica, 2017

During the summer of 2013, several specimens of Phoenicopterus chilensis (Phoenicopteridae) were ... more During the summer of 2013, several specimens of Phoenicopterus chilensis (Phoenicopteridae) were found dead from unknown causes, in lakes from the endorheic system "Encadenadas del Oeste", Buenos Aires Province, Argentina. Two species of Nematoda were recovered from the proventriculus, one of them new for science. The tetramerid Tetrameres (Tetrameres) salina n. sp. is mainly characterized by having reduced pseudolabia, lips absent, six bifid teeth, males with lateral alae, four rows of somatic spines and length ratio of spicules 1:12-32, and large females with eggs lacking polar filaments. The acuariid, Echinuria skrjabinensis is described and illustrated, this finding represent the second report of this nematode in Argentina and the first record in flamingos. This is the first record of helminths parasitizing wild Chilean Flamingos, but it is not possible to ensure that they accomplish their life cycle in this system of lakes, because the migratory movements of the popul...

Research paper thumbnail of Endogenous heptapeptide Met-enkephalin-Gly-Tyr binds differentially to duplicate delta opioid receptors from zebrafish

Peptides, 2007

Met-enkephalin-Gly-Tyr (MEGY) is an endogenous peptide that binds to opioid sites in zebrafish an... more Met-enkephalin-Gly-Tyr (MEGY) is an endogenous peptide that binds to opioid sites in zebrafish and in rat brain homogenates. The aim of this work is to characterize the binding profile of this opioid ligand on two duplicate delta receptors from zebrafish, ZFOR1 and ZFOR4. Our results show that, while ZFOR1 presents one single binding site for [(3)H]-MEGY (K(D)=4.0+/-0.4 nM), the experimental data from ZFOR4 fit better to the two-site binding model (K(D1)=0.8+/-0.2 nM and K(D2)=30.2+/-10.2 nM). Two other MEGY synthetic analogues, (D-Ala(2))-MEGY and (D-Ala(2), Val(5))-MEGY were also prepared and tested, together with the original peptide MEGY and other opioid ligands, in competition binding assays. While these peptides presented K(i) values on the nanomolar range when using [(3)H]-MEGY as radioligand, these parameters were two orders higher in competition binding assays with the antagonist [(3)H]-diprenorphine. Functional [(35)S]GTPgammaS stimulation analysis has revealed that these two receptors can be activated by several opioid agonists. Our results prove that although the MEGY peptide acts as an agonist on ZFOR1 and ZFOR4, there are subtle pharmacological differences between these two delta opioid receptors from zebrafish.

Research paper thumbnail of New kappa opioid receptor from zebrafish Danio rerio

Neuroscience Letters, 2006

A cDNA that encodes a kappa opioid receptor like from zebrafish (ZFOR3) has been cloned and chara... more A cDNA that encodes a kappa opioid receptor like from zebrafish (ZFOR3) has been cloned and characterized. The encoded protein is 377 residues long and presents 70% identity with the mammalian kappa receptors, although less homology is found in the amino-and carboxyl-terminus as well as in the extracellular loops. In situ hybridization studies have revealed that ZFOR3 mRNA is highly expressed in particular brain areas that coincide with the expression of the kappa opioid receptor in other species. When ZFOR3 is stably expressed in HEK293 cells, [ 3 H]-diprenorphine binds with high affinity (K D = 1.05 ± 0.26 nM), being this value on the same range as those reported for mammalian kappa opioid receptors. On the other hand, the selective agonist for mammalian kappa receptors U69,593 does not bind to ZFOR3. [ 3 H]-diprenorphine binding is readily displaced by the peptidic ligand dynorphin A and by the non-endogenous compounds bremazocine, naloxone and morphine, although with different affinities. Our results demonstrate that ZFOR3 is a unique model to study the kappa opioid receptor functionality.

Research paper thumbnail of Sesquiterpene lactone from Wunderlichia crulsiana inhibits the respiratory burst of leukocytes triggered by distinct biochemical pathways

Life Sciences, 2003

The sesquiterpene lactone tubiferin was chemically purified from the brazilian native plant Wunde... more The sesquiterpene lactone tubiferin was chemically purified from the brazilian native plant Wunderlichia crulsiana and identified by NMR and GC/MS data. Its ability to inhibit the respiratory burst of peritoneal inflammatory polymorphonuclear leukocytes (PMN) stimulated upon addition of phorbol miristate acetate (PMA), opsonized zymosan (OZ), and N-formyl-methionyl-leucyl-phenylalanine (fMLP) was evaluated. The tubiferin inhibition was more pronounced when PMN were stimulated through the protein kinase C pathway (PMA) compared to the alternative complement pathway (OZ). The inhibition when PMN were triggered by a chemoatractant stimulus (fMLP) was similar to that achieved with OZ-stimulated phagocytes. Tubiferin showed dose-dependent effects on the PMN respiratory burst triggered by the three different substances, and also decreased substancially the carrageenan-induced mice paw edema.

Research paper thumbnail of Characterization of a new duplicate δ-opioid receptor from zebrafish

Journal of Molecular Endocrinology, 2006

A new full-length cDNA (ZFOR4) that encodes an opioid receptor has been isolated from the teleost... more A new full-length cDNA (ZFOR4) that encodes an opioid receptor has been isolated from the teleost zebrafish. The encoded polypeptide is 375 amino acids long and shows high sequence similarity to other δ-opioid receptors, including ZFOR1, the other δ-opioid receptor from zebrafish previously characterized by us. In situ hybridization studies have revealed that ZFOR4 mRNA is highly expressed in particular brain areas that coincide with the expression of the δ-opioid receptor in other species. Pharmacological analysis of ZFOR4 shows specific and saturable binding with [3H] diprenorphine, displaying one binding site with KD = 3.42 ± 0.38 nM and a receptor density of 6231 ± 335 fmol/mg protein. Competition-binding experiments were performed using [3H]diprenorphine and several unlabelled ligands (peptidic and non-peptidic). The order of affinity obtained is Met-enkephalin>Naloxone>Leu-enkephalin>Dynorphin A≫BW373U86>Morphine≫≫ [D-Pen2,D-Pen5]-Enkephalin, U69,593. [35S]GTPγS st...

Research paper thumbnail of Population dynamics of the freshwater gastropod Chilina fluminea (Chilinidae), of temperate area from Argentina

ABSTRACT The presence and density of gastropods, and the individual growth rate of Chilina flumin... more ABSTRACT The presence and density of gastropods, and the individual growth rate of Chilina fluminea snails at Río de la Plata beach, Berisso, Buenos Aires province, Argentina, were analyzed to obtain population data about hosts that could be useful for control of the free-swimming larval stages (cercariae). Chilina fluminea has a unique annual reproductive period during winter, whereas other gastropods inhabiting the same area reproduce one to three times a year, but never in winter. Thus, autumn, the season before reproduction and oviposition, is the most adequate season for taking actions to regulate the size of C. fluminea populations to reduce possible cases of human schistosomic dermatitis.

Research paper thumbnail of The Giant African Snail,Achatina fulica(Gastropoda: Achatinidae): Using Bioclimatic Models to Identify South American Areas Susceptible to Invasion

American Malacological Bulletin, 2013

The best way to reduce problems related to invasive species is by preventing introductions into p... more The best way to reduce problems related to invasive species is by preventing introductions into potentially susceptible areas. The purpose of this study was to create distribution models for the invasive gastropod Achatina fulica Bowdich, 1822 in South America in order to evaluate its potential geographic distribution and identify areas at potential risk. This mollusc, considered one of the 100 world's worst invasive alien species, is the focus of intense concern due to its impact on agriculture, human health, and native fauna. We tested two commonly used ecological niche modeling methods: Genetic Algorithm for Rule-Set Prediction (GARP) and Maximum Entropy (MaxEnt). Models were run with occurrence points obtained from several sources, including the scientifi c literature, international databases, governmental reports and newspapers, WorldClim bioclimatic variables, and altitude. Models were evaluated with the threshold-independent Receiver Operating Characteristic (ROC) and Area Under the Curve (AUC). Both models had consistent performances with similar areas predicted as susceptible, including areas already affected and new potentially susceptible areas in both tropical and temperate regions of South America.

Research paper thumbnail of First Records of Four Exotic Slugs in Argentina

American Malacological Bulletin, 2013

This paper reports for the fi rst time the occurrence of four exotic terrestrial slug species in ... more This paper reports for the fi rst time the occurrence of four exotic terrestrial slug species in Argentina: Lehmannia valentiana (Férussac, 1823) (Limacidae), Deroceras invadens Reise et al. 2011 (Agriolimacidae), Arion intermedius Normand, 1852 (Arionidae) and Meghimatium pictum (Stolyczka, 1873) (Philomycidae). The study is based on specimens deposited in museums in Argentina. Both the morphologic characteristics and the mitochondrial cytochrome oxidase I gene sequences were used to identify the exotic species. Phylogenetic analyses were also carried out in order to explore the location of their origins. Lehmannia valentiana had the oldest records and has been widely distributed in Argentina. Deroceras invadens and A. intermedius were found to be restricted to the southern portion of the country. Meghimatium pictum was recorded in the northwest and northeast Argentina, and the DNA sequences analyzed from this species were more closely related to specimens from the west of the Strait of Taiwan. A determination of the origin of the other species was impossible because either the sequences analyzed grouped with samples from different geographical origins or only few sequences were available for comparison. In view of the invasive potential of these slug species, the present work provides new and potentially useful DNA sequence data obtained from morphologically-confi rmed specimens. Information provided from these analyses should assist in making a rapid identifi cation of these exotic slugs by nonspecialists and governmental authorities who are responsible for managing and controlling the presence of exotic species.

Research paper thumbnail of Improved high-performance liquid chromatography-DAD method for the simultaneous analysis of quercetin and kaempferol in the stems of <i>Cissus quadrangularis</i> Linn

Acta Chromatographica, 2009

ABSTRACT A simple, rapid, and specific reversed-phase HPLC method with DAD detection has been use... more ABSTRACT A simple, rapid, and specific reversed-phase HPLC method with DAD detection has been used for analysis of two flavonoids, quercetin and kaempferol, in Cissus quadrangularis Linn. The flavonoids were well resolved within 10 min, and quantification was achieved, on an endcapped C(18) column at 370 nm with acetonitrile-phosphate buffer (pH 3.4, adjusted with glacial acetic acid) 60:40 (v/v) as isocratic mobile phase at a flow rate of 1.0 mL min(-1). The method was validated for limit of detection, limit of quantification, linearity, precision, accuracy, and recovery. Linearity was demonstrated over the range 0.75 to 10 mu g mL(-1) for quercetin and 1.0 to 10 mu g mL(-1) for kaempferol with good correlation coefficients (r(2) &gt; 0.998). Detection limits were 0.075 and 0.10 mu g mL(-1) for quercetin and kaempferol respectively. Recovery was 98.0-105.3% for quercetin and 95.0-101.1% for kaempferol. The method was successfully applied to analysis of two flavonoids in four samples of Cissus quadrangularis Linn.

Research paper thumbnail of Adverse Effects in Patients with Intellectual and Developmental Disabilities Hospitalized at the University Clinical Hospital

Journal of Personalized Medicine

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Research paper thumbnail of Synthesis, biological and structural characterization of novel glycopeptide analogs of nociceptin

Research paper thumbnail of Incidence of Neonatal Abstinence Syndrome (NAS) in Castilla y Leon (Spain)

Children, 2021

Introduction: Neonatal Abstinence Syndrome (NAS) is considered a Public Health problem that is de... more Introduction: Neonatal Abstinence Syndrome (NAS) is considered a Public Health problem that is defined as a group of symptoms that appear in the newborn due to withdrawal from intrauterine drug exposure. Objective: The aim of this study was to analyze the incidence of NAS in Castilla y León from 2000 to 2019. Methodology: Data of NAS cases in Castilla y León from 2000 to 2019 were obtained. NAS incidence per 1000 births was calculated and the correlation among data from different provinces and years was analyzed. Results: The cumulative incidence of NAS in Castilla y León per 1000 births between 2000-2019 was 0.91‰, with great interprovincial variability. The provinces of Zamora and Palencia stand out, with high incidence rates of NAS despite their low birth rates. The temporal trend points towards a decrease in incidence from 2000 to 2019. Opioids such as methadone, cannabis, benzodiazepines and poly-drug use are the most prevalent drugs causing NAS, and it has also been observed t...

Research paper thumbnail of Cultural Appreciation or Cultural Appropriation

Bloomsbury Fashion Business Cases, 2018

Research paper thumbnail of Aportacion al estudio de los mecanismos de transduccion de la señal de los receptores opioides. (aplicacion a los problemas del dolor y de la tolerancia y dependencia a drogas opiaceas)

En este trabajo se han estudiado algunos de los mecanismos bioquimicos responsables de la activid... more En este trabajo se han estudiado algunos de los mecanismos bioquimicos responsables de la actividad de los agentes opiaceos, utilizando el pez cebra como modelo experimental. Primeramente hemos clonado y caracterizado la pronociceptina y prodinorfina de pez cebra, encontrando en estos precursores nuevas secuencias para peptidos opioides. Seguidamente hemos caracterizado farmacologicamente el peptido Met-encefalina-Gly-Tyr, demostrando que se une a receptores opioides de pez cebra y mamifero, pudiendo actuar como ligando endogeno de los receptores ZFOR1 y ZFOR4. Asimismo, la dinorfina A de pez cebra se une a todos los receptores opioides de pez cebra. El estudio de la internalizacion del receptor ZFOR4 ha demostrado que este receptor es internalizado por la etorfina y por peptidos endogenos, presentando diferencias en la dosis efectiva media, pero no en la cinetica. El receptor ZFOR3 solo es internalizado por la dinorfina A o por la dinorfina 1-13, con una cinetica y dosis efectiva m...

Research paper thumbnail of Checklist of the nematode parasites of wild birds of Argentina

Revue suisse de Zoologie, 2020

BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access t... more BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.

Research paper thumbnail of Revisión de dos especies de Physidae

Revista Mexicana de Biodiversidad, 2011

Resumen. A pesar de los numerosos trabajos que abordan desde diferentes ópticas la sistemática de... more Resumen. A pesar de los numerosos trabajos que abordan desde diferentes ópticas la sistemática de Physidae, la situación taxonómica de las entidades de esta familia presentes en la Argentina es aún confusa. Por lo tanto, se abordó el estudio de las 2 especies de hallazgo más frecuente en el país, realizando una actualización de la descripción de las mismas para confirmar su estatus taxonómico y facilitar su correcta identificación. Se analizaron ejemplares de 5 localidades diferentes de cada especie. Para la redescripción se analizaron fundamentalmente caracteres de la conchilla, morfología externa, rádula y reproductor. Las diferencias inter-específicas de las características de las conchillas y de las partes blandas fueron analizadas estadísticamente por separado, mediante análisis de los componentes principales y factorial discriminante. Los caracteres observados permitieron concluir que la correcta denominación de las especies aquí estudiadas es Stenophysa marmorata (Guilding, 1828) y Physa acuta Draparnaud, 1805. Si bien existen diferencias conquiológicas entre estas 2 especies, queda demostrado que es importante la observación de las partes blandas para una correcta determinación.

Research paper thumbnail of Desarrollo De Competencias Investigativas en Los Institutos Tecnológicos

Revista de Investigación , Formación y Desarrollo: generando productividad institucional., 2017

Las Instituciones de la Educación Superior son reconocidas cada vez más como un instrumento de de... more Las Instituciones de la Educación Superior son reconocidas cada vez más como un instrumento de desarrollo y están consideradas como factor clave para incrementar la competitividad y la calidad de vida de los ciudadanos, el desafío que se les presenta es considerable si se tiene en cuenta que se deben de enfrentar a una realidad en la cual los procesos de aprendizaje están en transformación constante exigiéndoles cada día más. Una de las principales transformaciones de las instituciones de educación superior se fundamenta en la generación de ciencia y tecnología suficiente revelando a través de ella el desarrollo que toda institución de educación superior tie - ne que obtener. Las competencias investigativas son un eje esencial en el desarrollo del aprendizaje organizacional de toda institución de educación superior transformándose en un aspecto esencial revelando que tan pertinente es la educación que se brinda tomando en consideración a la sociedad

Research paper thumbnail of Figure 28 from: Núñez V, Damborenea C, Darrigran G (2019) Illustrated catalogue of type specimens of Volutidae (Gastropoda) in the Malacological Collection of the Museo de La Plata, Argentina. Zoosystematics and Evolution 95(1): 65-93. https://doi.org/10.3897/zse.95.30541

The Malacology Collection of the Museo de La Plata contains more 13,000 lots from various regions... more The Malacology Collection of the Museo de La Plata contains more 13,000 lots from various regions of Argentina and other South American countries. The Collection also includes 511 type lots. Among the oldest type specimens are a large series of marine gastropod from Patagonia which were studied by Fernando Lahille in 1895. He was one of the first's naturalists of the Museo de La Plata, and there between 1893 and 1899, he made several studies in zoology. During that time, he described three species and forty varieties of Volutidae. Herein, we compare Lahille's type specimens, label data, number, and specimen information to the original descriptions and illustrations of these taxa. Each taxon has been photographed in multiple views. This historic type material is entirely composed of shells. This work is the first of a series of photographic catalogues of type material from the Malacology Collection of the Invertebrate Division of Museo de La Plata.

Research paper thumbnail of Nematode parasites of the Chilean Flamingo, Phoenicopterus chilensis (Phoenicopteridae) from Central Argentina, with a description of a new species of Tetrameres (Tetrameridae)

Acta parasitologica, 2017

During the summer of 2013, several specimens of Phoenicopterus chilensis (Phoenicopteridae) were ... more During the summer of 2013, several specimens of Phoenicopterus chilensis (Phoenicopteridae) were found dead from unknown causes, in lakes from the endorheic system "Encadenadas del Oeste", Buenos Aires Province, Argentina. Two species of Nematoda were recovered from the proventriculus, one of them new for science. The tetramerid Tetrameres (Tetrameres) salina n. sp. is mainly characterized by having reduced pseudolabia, lips absent, six bifid teeth, males with lateral alae, four rows of somatic spines and length ratio of spicules 1:12-32, and large females with eggs lacking polar filaments. The acuariid, Echinuria skrjabinensis is described and illustrated, this finding represent the second report of this nematode in Argentina and the first record in flamingos. This is the first record of helminths parasitizing wild Chilean Flamingos, but it is not possible to ensure that they accomplish their life cycle in this system of lakes, because the migratory movements of the popul...

Research paper thumbnail of Endogenous heptapeptide Met-enkephalin-Gly-Tyr binds differentially to duplicate delta opioid receptors from zebrafish

Peptides, 2007

Met-enkephalin-Gly-Tyr (MEGY) is an endogenous peptide that binds to opioid sites in zebrafish an... more Met-enkephalin-Gly-Tyr (MEGY) is an endogenous peptide that binds to opioid sites in zebrafish and in rat brain homogenates. The aim of this work is to characterize the binding profile of this opioid ligand on two duplicate delta receptors from zebrafish, ZFOR1 and ZFOR4. Our results show that, while ZFOR1 presents one single binding site for [(3)H]-MEGY (K(D)=4.0+/-0.4 nM), the experimental data from ZFOR4 fit better to the two-site binding model (K(D1)=0.8+/-0.2 nM and K(D2)=30.2+/-10.2 nM). Two other MEGY synthetic analogues, (D-Ala(2))-MEGY and (D-Ala(2), Val(5))-MEGY were also prepared and tested, together with the original peptide MEGY and other opioid ligands, in competition binding assays. While these peptides presented K(i) values on the nanomolar range when using [(3)H]-MEGY as radioligand, these parameters were two orders higher in competition binding assays with the antagonist [(3)H]-diprenorphine. Functional [(35)S]GTPgammaS stimulation analysis has revealed that these two receptors can be activated by several opioid agonists. Our results prove that although the MEGY peptide acts as an agonist on ZFOR1 and ZFOR4, there are subtle pharmacological differences between these two delta opioid receptors from zebrafish.

Research paper thumbnail of New kappa opioid receptor from zebrafish Danio rerio

Neuroscience Letters, 2006

A cDNA that encodes a kappa opioid receptor like from zebrafish (ZFOR3) has been cloned and chara... more A cDNA that encodes a kappa opioid receptor like from zebrafish (ZFOR3) has been cloned and characterized. The encoded protein is 377 residues long and presents 70% identity with the mammalian kappa receptors, although less homology is found in the amino-and carboxyl-terminus as well as in the extracellular loops. In situ hybridization studies have revealed that ZFOR3 mRNA is highly expressed in particular brain areas that coincide with the expression of the kappa opioid receptor in other species. When ZFOR3 is stably expressed in HEK293 cells, [ 3 H]-diprenorphine binds with high affinity (K D = 1.05 ± 0.26 nM), being this value on the same range as those reported for mammalian kappa opioid receptors. On the other hand, the selective agonist for mammalian kappa receptors U69,593 does not bind to ZFOR3. [ 3 H]-diprenorphine binding is readily displaced by the peptidic ligand dynorphin A and by the non-endogenous compounds bremazocine, naloxone and morphine, although with different affinities. Our results demonstrate that ZFOR3 is a unique model to study the kappa opioid receptor functionality.

Research paper thumbnail of Sesquiterpene lactone from Wunderlichia crulsiana inhibits the respiratory burst of leukocytes triggered by distinct biochemical pathways

Life Sciences, 2003

The sesquiterpene lactone tubiferin was chemically purified from the brazilian native plant Wunde... more The sesquiterpene lactone tubiferin was chemically purified from the brazilian native plant Wunderlichia crulsiana and identified by NMR and GC/MS data. Its ability to inhibit the respiratory burst of peritoneal inflammatory polymorphonuclear leukocytes (PMN) stimulated upon addition of phorbol miristate acetate (PMA), opsonized zymosan (OZ), and N-formyl-methionyl-leucyl-phenylalanine (fMLP) was evaluated. The tubiferin inhibition was more pronounced when PMN were stimulated through the protein kinase C pathway (PMA) compared to the alternative complement pathway (OZ). The inhibition when PMN were triggered by a chemoatractant stimulus (fMLP) was similar to that achieved with OZ-stimulated phagocytes. Tubiferin showed dose-dependent effects on the PMN respiratory burst triggered by the three different substances, and also decreased substancially the carrageenan-induced mice paw edema.

Research paper thumbnail of Characterization of a new duplicate δ-opioid receptor from zebrafish

Journal of Molecular Endocrinology, 2006

A new full-length cDNA (ZFOR4) that encodes an opioid receptor has been isolated from the teleost... more A new full-length cDNA (ZFOR4) that encodes an opioid receptor has been isolated from the teleost zebrafish. The encoded polypeptide is 375 amino acids long and shows high sequence similarity to other δ-opioid receptors, including ZFOR1, the other δ-opioid receptor from zebrafish previously characterized by us. In situ hybridization studies have revealed that ZFOR4 mRNA is highly expressed in particular brain areas that coincide with the expression of the δ-opioid receptor in other species. Pharmacological analysis of ZFOR4 shows specific and saturable binding with [3H] diprenorphine, displaying one binding site with KD = 3.42 ± 0.38 nM and a receptor density of 6231 ± 335 fmol/mg protein. Competition-binding experiments were performed using [3H]diprenorphine and several unlabelled ligands (peptidic and non-peptidic). The order of affinity obtained is Met-enkephalin>Naloxone>Leu-enkephalin>Dynorphin A≫BW373U86>Morphine≫≫ [D-Pen2,D-Pen5]-Enkephalin, U69,593. [35S]GTPγS st...

Research paper thumbnail of Population dynamics of the freshwater gastropod Chilina fluminea (Chilinidae), of temperate area from Argentina

ABSTRACT The presence and density of gastropods, and the individual growth rate of Chilina flumin... more ABSTRACT The presence and density of gastropods, and the individual growth rate of Chilina fluminea snails at Río de la Plata beach, Berisso, Buenos Aires province, Argentina, were analyzed to obtain population data about hosts that could be useful for control of the free-swimming larval stages (cercariae). Chilina fluminea has a unique annual reproductive period during winter, whereas other gastropods inhabiting the same area reproduce one to three times a year, but never in winter. Thus, autumn, the season before reproduction and oviposition, is the most adequate season for taking actions to regulate the size of C. fluminea populations to reduce possible cases of human schistosomic dermatitis.

Research paper thumbnail of The Giant African Snail,Achatina fulica(Gastropoda: Achatinidae): Using Bioclimatic Models to Identify South American Areas Susceptible to Invasion

American Malacological Bulletin, 2013

The best way to reduce problems related to invasive species is by preventing introductions into p... more The best way to reduce problems related to invasive species is by preventing introductions into potentially susceptible areas. The purpose of this study was to create distribution models for the invasive gastropod Achatina fulica Bowdich, 1822 in South America in order to evaluate its potential geographic distribution and identify areas at potential risk. This mollusc, considered one of the 100 world's worst invasive alien species, is the focus of intense concern due to its impact on agriculture, human health, and native fauna. We tested two commonly used ecological niche modeling methods: Genetic Algorithm for Rule-Set Prediction (GARP) and Maximum Entropy (MaxEnt). Models were run with occurrence points obtained from several sources, including the scientifi c literature, international databases, governmental reports and newspapers, WorldClim bioclimatic variables, and altitude. Models were evaluated with the threshold-independent Receiver Operating Characteristic (ROC) and Area Under the Curve (AUC). Both models had consistent performances with similar areas predicted as susceptible, including areas already affected and new potentially susceptible areas in both tropical and temperate regions of South America.

Research paper thumbnail of First Records of Four Exotic Slugs in Argentina

American Malacological Bulletin, 2013

This paper reports for the fi rst time the occurrence of four exotic terrestrial slug species in ... more This paper reports for the fi rst time the occurrence of four exotic terrestrial slug species in Argentina: Lehmannia valentiana (Férussac, 1823) (Limacidae), Deroceras invadens Reise et al. 2011 (Agriolimacidae), Arion intermedius Normand, 1852 (Arionidae) and Meghimatium pictum (Stolyczka, 1873) (Philomycidae). The study is based on specimens deposited in museums in Argentina. Both the morphologic characteristics and the mitochondrial cytochrome oxidase I gene sequences were used to identify the exotic species. Phylogenetic analyses were also carried out in order to explore the location of their origins. Lehmannia valentiana had the oldest records and has been widely distributed in Argentina. Deroceras invadens and A. intermedius were found to be restricted to the southern portion of the country. Meghimatium pictum was recorded in the northwest and northeast Argentina, and the DNA sequences analyzed from this species were more closely related to specimens from the west of the Strait of Taiwan. A determination of the origin of the other species was impossible because either the sequences analyzed grouped with samples from different geographical origins or only few sequences were available for comparison. In view of the invasive potential of these slug species, the present work provides new and potentially useful DNA sequence data obtained from morphologically-confi rmed specimens. Information provided from these analyses should assist in making a rapid identifi cation of these exotic slugs by nonspecialists and governmental authorities who are responsible for managing and controlling the presence of exotic species.

Research paper thumbnail of Improved high-performance liquid chromatography-DAD method for the simultaneous analysis of quercetin and kaempferol in the stems of <i>Cissus quadrangularis</i> Linn

Acta Chromatographica, 2009

ABSTRACT A simple, rapid, and specific reversed-phase HPLC method with DAD detection has been use... more ABSTRACT A simple, rapid, and specific reversed-phase HPLC method with DAD detection has been used for analysis of two flavonoids, quercetin and kaempferol, in Cissus quadrangularis Linn. The flavonoids were well resolved within 10 min, and quantification was achieved, on an endcapped C(18) column at 370 nm with acetonitrile-phosphate buffer (pH 3.4, adjusted with glacial acetic acid) 60:40 (v/v) as isocratic mobile phase at a flow rate of 1.0 mL min(-1). The method was validated for limit of detection, limit of quantification, linearity, precision, accuracy, and recovery. Linearity was demonstrated over the range 0.75 to 10 mu g mL(-1) for quercetin and 1.0 to 10 mu g mL(-1) for kaempferol with good correlation coefficients (r(2) &gt; 0.998). Detection limits were 0.075 and 0.10 mu g mL(-1) for quercetin and kaempferol respectively. Recovery was 98.0-105.3% for quercetin and 95.0-101.1% for kaempferol. The method was successfully applied to analysis of two flavonoids in four samples of Cissus quadrangularis Linn.