Anthropogenic microfibers are highly abundant at the Burdwood Bank seamount, a protected sub-Antarctic environment in the Southwestern Atlantic Ocean.

Microplastics debris in the marine environment have been widely studied across the globe. Within these particles, the most abundant and prevalent type in the oceans are anthropogenic microfibers (MFs), although they have been historically overlooked mostly due to methodological constraints. MFs are currently considered omnipresent in natural environments, however, contrary to the Northern Hemisphere, data on their abundance and distribution in Southern Oceans ecosystems are still scarce, in particular for sub-Antarctic regions. Using Niskin bottles we've explored microfibers abundance and distribution in the water column (3-2450 m depth) at the Burdwood Bank (BB), a seamount located at the southern extreme of the Patagonian shelf, in the Southwestern Atlantic Ocean. The MFs detected from filtered water samples were photographed and measured using ImageJ software, to estimate length, width, and the projected surface area of each particle. Our results indicate that small pieces of fibers are widespread in the water column at the BB (mean of 17.4 ± 12.6 MFs.L-1), from which, 10.6 ± 5.3 MFs.L-1 were at the surface (3-10 m depth), 20 ± 9 MFs.L-1 in intermediate waters (41-97 m), 24.6 ± 17.3 MFs.L-1 in deeper waters (102-164 m), and 9.2 ± 5.3 MFs.L-1 within the slope break of the seamount. Approximately 76.1% of the MFs were composed of Polyethylene terephthalate, and the abundance was dominated by the size fraction from 0.1 to 0.3 mm of length. Given the high relative abundance of small and aged MFs, and the oceanographic complexity of the study area, we postulate that MFs are most likely transported to the BB via the Antarctic Circumpolar Current. Our findings imply that this sub-Antarctic protected ecosystem is highly exposed to microplastic pollution, and this threat could be spreading towards the highly productive waters, north of the study area.

Microplastics pollution in the intertidal limpet, Nacella magellanica, from Beagle Channel (Argentina).

Microplastics (MPs) have been identified in diverse marine invertebrates; however, there are few studies on limpets. This study aimed to evaluate and compare the presence of MPs in Nacella magellanica among sites of the Beagle Channel with different degree of anthropogenic influence. Intertidal limpets were sampled in three sites: Ushuaia Bay (UB) (inside Ushuaia city), a site with high anthropogenic influence owing to population growth, and fisheries, industrial and port activities; Ensenada Zaratiegui (EZ) and Playa Larga (PL) (west and east of Ushuaia city, respectively), both sites with a certain degree of environmental protection and low anthropogenic influence. MPs were isolated from the whole soft tissue of individuals by oxidative digestions with H2O2 (30%; 1:10 w/v). MPs occurrence was 100% in organisms from UB and EZ, whereas 90% in PL. Limpets from UB showed 10 ± 6.69 MPs/ind and 2.22 ± 0.78 MPs/g ww, while in PL and EZ there were 2.90 ± 2.02 MPs/ind and 0.96 ± 0.94 MPs/g ww; and 5.60 ± 2.59 MPs/ind and 2.41 ± 1.47 MPs/g ww, respectively. Fibres were the most abundant MPs type, followed by fragments and films. Fibres and films were identified as semi-synthetic cellulose and, although the polymer matrix of fragments was masked by copper phthalocyanine, one of them could be identified as polystyrene. As expected, the highest abundance of MPs was found in UB. However, a lower abundance of particles was detected in PL (downstream of UB) than in EZ (upstream of UB). This could be due to the influence of both the main current of the Beagle Channel and fluvial discharges, reducing the buoyancy of MPs. More studies are needed to understand the contribution of regional and local features to the accumulation of MPs in these environments and their interaction with the biota.

First report of microplastics presence in the mussel Mytilus chilensis from Ushuaia Bay (Beagle Channel, Tierra del Fuego, Argentina).

Microplastics contamination is reported for the first time on Mytilus chilensis from Ushuaia Bay, one of the most remote areas of South America. Our results demonstrate the occurrence of microplastics in all samples, with an average of 8.6 ±â€¯3.53 items per individual. Fibers and fragments were the most abundant, with a percentage of 77.91 and 17.44%, respectively. The average length of the fibers was 742.3 ±â€¯702.1 µm, while the average cross-sectional area of fragments was 1944.80 ±â€¯960.94 µm2. The polymers identified were polyamides, semi-synthetic cellulosic materials, and PVC copolymers. The number of microplastics per individual was greater than those reported in even more populated regions. Probably, the modifications included in the technique led to optimize the extraction of MPs, reflecting the detection of a greater number of particles. M. chilensis could play a role in an extensive evaluation of MPs in the Ushuaia Bay, providing information on the interaction of MPs and biota.

Presentaciones poco frecuentes de diabetes tipo MODY: el ejemplo de MODY tipo 5 y las formas de novo de MODY tipo 2 / Infrequent presentations of MODY diabetes: the example of MODY type 5 and de novo forms of MODY type 2

La diabetes tipo MODY se produce por alteraciones en genes relacionados con el metabolismo de la célula beta pancreática. El tipo 2 es uno de los más frecuentes y se produce por alteraciones en el gen GCK (glucoquinasa) y el tipo 5 es mucho menos frecuente y se produce por alteraciones en el gen HNF1B (factor nuclear hepático 1B). Se presentan con herencia autosómica dominante, aunque se ha descripto la presencia de mutaciones de novo. El objetivo del trabajo fue buscar mutaciones en el gen GCK en pacientes sin antecedentes familiares pero con características clínicas de MODY2 y mutaciones en el gen HNF1B en pacientes con características clínicas de MODY5 con y sin antecedentes familiares. Para ello a partir de ADN se realizó la secuenciación de cada gen por el método de Sanger o por secuenciación de nueva generación. Como resultado, se hallaron mutaciones en el gen GCK en cuatro pacientes sin antecedentes familiares y mutaciones en el gen del HNF1B en dos pacientes, uno de ellos sin antecedentes familiares. Como conclusión puede afirmarse que las mutaciones de novo en el gen de la GCK son más frecuentes de lo descripto, por lo cual se recomienda el estudio del gen en pacientes con características compatibles aún sin antecedentes familiares. También es importante el estudio del gen HNF1B en pacientes con características típicas ya que deben tratarse no sólo por sus alteraciones renales sino por la diabetes presente; de esta manera se logra un correcto diagnóstico para instaurar el tratamiento más adecuado

Human Papillomavirus Types Involved in External Genital Warts in a Group of Argentinian Women in Buenos Aires.

OBJECTIVES: The aim of the study was to understand which human papillomavirus (HPV) types are involved in external genital warts (GWs) in a group of Argentinian women in Buenos Aires. METHODS: One hundred sixty consecutive women 15 to 45 years old with GWs were enrolled. All patients underwent confirmatory biopsy. In 150 of 160 patients, the diagnosis of GWs was confirmed by histology, DNA-HPV was investigated using polymerase chain reaction, and sequence analysis with generic primers MY09/11 was performed. RESULTS: HPV 6 and/or 11 was detected in 93.3% patients (140/150). HPV 6 was by far the most common type (80%), followed by HPV 11 (12.7%). Coinfection with these 2 types occurred in 0.7%. HPV 16 was found in 2% and HPV 73 in 0.7%. CONCLUSION: HPV 6 and/or 11 are present in 93.3% (95% confidence interval, 0.9-1.0) of external genital warts in a group of Argentinian women in Buenos Aires and, therefore, could be prevented with HPV vaccine (NCT 015998779).

Analysis of mutations in the glucokinase gene in people clinically characterized as MODY2 without a family history of diabetes.

BACKGROUND: Maturity-onset diabetes of the young 2 (MODY2) is a form of diabetes that is clinically characterized by early age at onset and mild hyperglycemia, and has a low risk of late complications. It is often underdiagnosed due to its mild symptoms. To date, over 600 different GCK/MODY2 mutations have been reported. Despite only a few de novo mutations having been described, recent studies have reported the detection of a higher frequency of this kind of mutation. Therefore, de novo mutations could be more frequent than previously described. Even though common recommendations regarding the diagnosis of monogenic diabetes include the existence of a strong family history of diabetes, here we describe the study of mutations in two families with a symptomatic individual with clear clinical features of MODY2 but without any family history of diabetes. METHODS: Genetic diagnosis in a group of participants with MODY2 characteristics was carried out by direct sequencing of coding regions of the GCK gene and analysis of mutations found using bioinformatics tools. RESULTS: We found two de novo mutations, one of them novel, constituting 14.29% of all the participants who were phenotyped as MODY2. CONCLUSIONS: The number of mutations in GCK/MODY2 or even other MODY-related genes is undoubtedly underestimated, as accepted criteria for performing genetic tests include family history of the pathology. These cases illustrate the value of analyzing the GCK gene in patients with clinical features of MODY2, even in the absence of family history of the condition as it is essential for establishing the correct treatment.

Genetic variability and phylogeny analysis of partial L1 gene of human papillomavirus variants in Buenos Aires, Argentina.

In the present study, the molecular characterization of HPV variants 16, 18, 31, 58, 6 and 11 within the MY06/MY11 L1 genomic region was performed in 128 sequences. For HPV 16, all of the sequences analyzed had a 3 nucleotide insertion resulting in the insertion of serine in the L1 protein sequence; and 4 sequences had at least one single nucleotide polymorphism (SNP). Twelve base substitutions were detected in HPV 58, 6 SNPs produced amino acid changes, and the other SNPs detected were found to be silent mutations. For HPV 31, 25 SNPs were detected as silent mutations. Of the 8 SNPs detected on HPV 18, three produced amino acid changes, the remaining SNPs detected were silent mutations. For HPV 6, 10 SNPs were detected and none of them produced amino acid changes. From the 16 sequences analyzed for HPV 11, two SNPs were detected and neither of them produced amino acid substitutions. Phylogenetic trees were constructed for HPV 16, HPV 18, HPV 31, HPV 58, HPV 6 and HPV 11. In the current study 8 new variants were identified based on sequencing of the L1 region. Changes in the L1 region of the HPV genome may be important for discriminating the infectious potential of different variants, as well as in defining epitopes relevant to vaccine design. The findings of this study indicate that there are new variants of HPV circulating in Argentina, which need to be confirmed by further analyses of the complete HPV genome.

Circulación de virus de influenza A y cepas resistentes a oseltamivir en el período invernal del año 2013 / Circulation of Influenza A Viruses and Oseltamivir-Resistant Strains during the 2013 Winter

Inicialmente el virus de influenza A(H1N1)pdm09 fue susceptible a los inhibidores de neuraminidasa oseltamivir y zanamivir. Las cepas virales resistentes presentan una sustitución que produce un cambio del aminoácido histidina (H) por una tirosina (Y) en el codón 274 del gen de la neuroaminidasa. El objetivo del trabajo fue realizar un análisis retrospectivo de los resultados obtenidos en muestras estudiadas para influenza A durante el periodo junio - agosto de 2013 y en las muestras positivas determinar la presencia de la mutación H274Y. Se estudiaron 1783 muestras de pacientes con diagnóstico presuntivo de influenza A(H1N1)pdm09, 171 (9.6%) resultaron positivas, a estas se les estudió la presencia de la mutación H274Y. Únicamente dos muestras presentaron la mutación de resistencia. Los métodos para detectar cepas de infuenza A(H1N1)pdm09 resistentes son necesarios para ayudar a los médicos en la selección de la terapia antiviral apropiada de la influenza.

Initially the circulating influenza virus A(H1N1)pdm09 was susceptible to neuraminidase inhibitors oseltamivir and zanamivir. Virtually all resistant viruses possess a substitution at codon 274 of the neuraminidase gene which produces a change of the amino acid histidine (H) to a tyrosine (Y). The aims of the study were to perform a retrospective analysis of samples studied in the Laboratory of Genomic Medicine - MANLAB for influenza A during the period June to August 2013 in Buenos Aires, and to determine the presence of the H274Y mutation. 1783 samples from patients with a presumptive diagnosis of influenza A(H1N1) pdm09 were studied, the virus was detected in 171 samples (9.6%). Then, we studied the presence of the mutation H274Y. Only two samples showed the characteristic resistance mutation. Methods for detecting oseltamivir-resistant A(H1N1)pdm09 influenza strains are needed to assist physicians in the selection of appropriate antiviral therapy for influenza treatment.

A new genus and species of Platyischnopidae (Amphipoda: Gammaridea) from the Argentine sea, South-West Atlantic ocean.

The family Platyischnopidae is herein reported for the first time in the Argentine Sea, South-West Atlantic Ocean. A new genus and species, Platyisao holodividum gen. et. sp. nov., collected off the coast of Buenos Aires and Río Negro provinces, is fully described and illustrated. Platyisao gen. nov. is distinguished from the eight other genera of Platyischnopidae by the gnathopods subchelate, and the telson elongate, completely cleft. In addition, the distribution of Tiburonella viscana (Barnard J.L., 1964), up to now known in the South-West Atlantic Ocean from Brazilian waters, is extended to the coast off Buenos Aires province, Argentina.

Distribución de genotipos del virus de hepatitis C en la población Argentina / Distribution of hepatitis C virus genotypes in an Argentine population / Distribuição dos genótipos do vírus da hepatite C na população Argentina

Mundialmente se han identificado 6 genotipos (1 al 6) del virus de la hepa­titis C (HCV). Dichos genotipos se subdividen en diferentes subtipos (a, b, c y otros). La respuesta al tratamiento instaurado depende del genotipo del virus infectante. El objetivo del trabajo fue determinar la frecuencia de los diferentes genotipos del HCV en la población de Argentina. Se estudiaron 510 pacientes infectados con HCV; la genotipificación del virus se realizó utilizando el equipo Versant HCV genotype assay 2.0 (LiPA). Los resultados obtenidos indican que el genotipo predominante del HCV en Argentina es el 1 (67,6%), con una prevalencia similar de subtipos 1a y 1b (33,3% y 34,5%, respectivamente). Se observó también una frecuencia similar de los genotipos 2 y 3 (14,5% cada uno). Con este estudio se actualizan los datos de las frecuencias de los diferentes genotipos de HCV que circulan en Argentina utilizando la nueva versión del reactivo para diagnóstico, el cual permitió una correcta subtipificación de las muestras.

Six hepatitis C virus genotypes have been identified worldwide so far. The­se genotypes have been subclassified into different subtypes (a, b, c and others). It is known that the response to treatment is highly dependent on the genotype involved. The aim of this work was to assess the frequency of occurrence of the different HCV genotypes in the population of Argentina. To this end, 510 infected patients were subjected to HCV genotyping using the commercial kit Versant HCV genotype assay 2.0. Results indicated that the genotype 1 was the most frequent (67.6%), and that subtypes 1a and 1b showed a similar prevalence (33.3% and 34.5%, respectively). Genotypes 2 and 3 also displayed a similar frequency (14.5% and 14.5% respectively). This study provides an update regarding the frequency of all HCV genotypes circulating in Argentina. The results were obtained by the novel version of the genotyping kit, which enabled a correct subtyping of samples.

Globalmente foram identificados 6 genótipos (1 ao 6) do vírus da hepatite C (HCV). Estes genótipos são subdivididos em vários subtipos (a, b, c, etc.). A resposta ao tratamento depende do genótipo do vírus infectante. O objetivo do estudo foi determinar a freqüência dos diferentes genótipos do HCV na população Argentina. Foram estudados 510 pacientes infectados com o HCV, a genotipagem do vírus foi realizada utilizando o kit Versant HCV genotype assay 2.0 (LiPA). Os resultados obtidos indicam que o genótipo predominante na Argentina é o tipo 1 (67,6%), observando-se uma prevalência dos subtipos 1a e 1b (33,3% e 34,5% respectivamente). Observou-se também uma freqüência semelhante do genótipos 2 e 3 (14,5% e 14,5% respectivamente). Este estudo atualiza os dados das freqüências dos diferentes genótipos do HCV em circulação na Argentina usando a nova versão do kit, o que permitiu uma correta subtipagem das amostras.

Distribución de genotipos del virus de hepatitis C en la población Argentina / Distribution of hepatitis C virus genotypes in an Argentine population / DistribuiþÒo dos genótipos do vírus da hepatite C na populaþÒo Argentina

Mundialmente se han identificado 6 genotipos (1 al 6) del virus de la hepa¡titis C (HCV). Dichos genotipos se subdividen en diferentes subtipos (a, b, c y otros). La respuesta al tratamiento instaurado depende del genotipo del virus infectante. El objetivo del trabajo fue determinar la frecuencia de los diferentes genotipos del HCV en la población de Argentina. Se estudiaron 510 pacientes infectados con HCV; la genotipificación del virus se realizó utilizando el equipo Versant HCV genotype assay 2.0 (LiPA). Los resultados obtenidos indican que el genotipo predominante del HCV en Argentina es el 1 (67,6%), con una prevalencia similar de subtipos 1a y 1b (33,3% y 34,5%, respectivamente). Se observó también una frecuencia similar de los genotipos 2 y 3 (14,5% cada uno). Con este estudio se actualizan los datos de las frecuencias de los diferentes genotipos de HCV que circulan en Argentina utilizando la nueva versión del reactivo para diagnóstico, el cual permitió una correcta subtipificación de las muestras.(AU)

Six hepatitis C virus genotypes have been identified worldwide so far. The¡se genotypes have been subclassified into different subtypes (a, b, c and others). It is known that the response to treatment is highly dependent on the genotype involved. The aim of this work was to assess the frequency of occurrence of the different HCV genotypes in the population of Argentina. To this end, 510 infected patients were subjected to HCV genotyping using the commercial kit Versant HCV genotype assay 2.0. Results indicated that the genotype 1 was the most frequent (67.6%), and that subtypes 1a and 1b showed a similar prevalence (33.3% and 34.5%, respectively). Genotypes 2 and 3 also displayed a similar frequency (14.5% and 14.5% respectively). This study provides an update regarding the frequency of all HCV genotypes circulating in Argentina. The results were obtained by the novel version of the genotyping kit, which enabled a correct subtyping of samples.(AU)

Globalmente foram identificados 6 genótipos (1 ao 6) do vírus da hepatite C (HCV). Estes genótipos sÒo subdivididos em vários subtipos (a, b, c, etc.). A resposta ao tratamento depende do genótipo do vírus infectante. O objetivo do estudo foi determinar a freq³Ûncia dos diferentes genótipos do HCV na populaþÒo Argentina. Foram estudados 510 pacientes infectados com o HCV, a genotipagem do vírus foi realizada utilizando o kit Versant HCV genotype assay 2.0 (LiPA). Os resultados obtidos indicam que o genótipo predominante na Argentina é o tipo 1 (67,6%), observando-se uma prevalÛncia dos subtipos 1a e 1b (33,3% e 34,5% respectivamente). Observou-se também uma freq³Ûncia semelhante do genótipos 2 e 3 (14,5% e 14,5% respectivamente). Este estudo atualiza os dados das freq³Ûncias dos diferentes genótipos do HCV em circulaþÒo na Argentina usando a nova versÒo do kit, o que permitiu uma correta subtipagem das amostras.(AU)

Contribution of alpha2-adrenoceptors to the mitogenic effect of catecholestrogen in human breast cancer MCF-7 cells.

Catecholestrogens are estrogen metabolites formed by hydroxylation of 17beta-estradiol and estrone at either the C-2 or C-4 position, rivaling the parent estrogens in concentration. The objective of the present work was to assess if their catechol group could make them induce proliferation of human breast cancer cells via alpha(2)-adrenoceptors. In competition studies in human breast cancer MCF-7 cells, high concentrations of 2-hydroxy-estradiol (2-OH-E(2)), 2-hydroxy-estrone (2-OH-E(1)) and 4-hydroxy-estrone (4-OH-E(1)) competed for [(3)H]-rauwolscine binding, whereas 4-hydroxy-estradiol (4-OH-E(2)) did not. The contribution of alpha(2)-adrenoceptors and estrogen receptors (ERs) in proliferation enhancement was analyzed with specific antagonists. The specific alpha(2)-adrenergic antagonist yohimbine partially reversed the effect of catecholestrogens except 4-OH-E(2). The selective ER downregulator ICI-182780 or fulvestrant partially or totally reversed the effect of all hydroxylated catecholestrogens. When analyzing the effect of the combination of both antagonists in MCF-7, the contribution of the alpha(2)-adrenoceptors and ERs for 2-OH-E(2), 2-OH-E(1) and 4-OH-E(1) was mixed, whereas for 4-OH-E(2), the only receptor implied was an ER. In MDA-MB-231 cells (ER-alpha negative) the proliferation stimulation by these three catecholestrogens and reversal by the adrenergic antagonist was also observed. It can be concluded that alpha(2)-adrenoceptors contribute at least in part to the mitogenic effect of 2-OH-E(2), 2-OH-E(1) and 4-OH-E(1).

Biodiversity of the Gammaridea and Corophiidea (Crustacea: Amphipoda) from the Beagle Channel and the Straits of Magellan: a preliminary comparison between their faunas

Gammaridea and Corophiidea amphipod species from the Beagle Channel and the Straits of Magellan were listed for the first time; their faunas were compared on the basis of bibliographic information and material collected in one locality at Beagle Channel (Isla Becasses). The species Schraderia serraticauda and Heterophoxus trichosus (collected at Isla Becasses) were cited for the first time for the Magellan region; Schraderia is the first generic record for this region. A total of 127 species were reported for the Beagle Channel and the Straits of Magellan. Sixty-two species were shared between both passages (71.3 % similarity). The amphipod species represented 34 families and 83 genera. The similarity at genus level was 86.4 %, whereas 23 of the 34 families were present in both areas. For all species, 86 had bathymetric ranges above 100 m and only 12 species ranged below 200 m depth. In the Beagle Channel, only one species had a depth record greater than 150 m, whereas in the Straits of Magellan, 15 had such a record. The Beagle Channel and the Straits of Magellan contain 57.5 % of the species, 71 % of the genera and 77.3 % of the families of Gammaridea and Corophiidea from the entire Magellan region.

Se confeccionó el primer listado de anfípodos Gammaridea y Corophiidea del Canal Beagle y del Estrecho de Magallanes, y se compararon, en forma preliminar, sus faunas con base en información bibliográfica y material recolectado en una localidad del Canal Beagle (Isla Becasses). Las especies Heterophoxus trichosus y Schraderia serraticauda (recolectadas en Isla Becasses) son citadas por primera vez para la región magallánica; Schraderia representa el primer registro genérico para dicha región. Un total de 127 especies fueron registradas para el Canal Beagle y el Estrecho de Magallanes, compartiendo entre ambos 62 especies, lo que representa una similitud del 71.3 %. El total de las especies pertenece a 34 familias y 83 géneros. La similitud a nivel genérico fue del 86.4 %, mientras que 23 familias estuvieron presentes en ambos pasajes. Del total de especies, 86 presentaron rangos de profundidad menores a los 100 m y sólo 12 especies superaron los 200 m. Sólo una especie tuvo un registro superior a los 150 m de profundidad en el Canal Beagle, mientras que 15 superaron dicha profundidad en el Estrecho de Magallanes. En el Canal Beagle y el Estrecho de Magallanes se registró el 57.5 % de las especies, 71 % de los géneros y 77.3 % de las familias conocidas para la región magallánica.