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Species of Trichoderma exert direct biocontrol activity against soil-borne plant pathogens due to their ability to compete for nutrients and to inhibit or kill their targets through the production of antibiotics and/or hydrolytic enzymes. In addition to these abilities, Trichoderma spp. have beneficial effects for plants, including the stimulation of defenses and the promotion of growth. Here we study the role in biocontrol of the T. parareesei Tparo7 gene, encoding a chorismate mutase (CM), a shikimate pathway branch point leading to the production of aromatic amino acids, which are not only essential components of protein synthesis but also the precursors of a wide range of secondary metabolites. We isolated T. parareesei transformants with the Tparo7 gene silenced. Compared with the wild-type, decreased levels of Tparo7 expression in the silenced transformants were accompanied by reduced CM activity, lower growth rates on different culture media, and reduced mycoparasitic behavior against the phytopathogenic fungi Rhizoctonia solani, Fusarium oxysporum and Botrytis cinerea in dual cultures. By contrast, higher amounts of the aromatic metabolites tyrosol, 2-phenylethanol and salicylic acid were detected in supernatants from the silenced transformants, which were able to inhibit the growth of F. oxysporum and B. cinerea. In in vitro plant assays, Tparo7-silenced transformants also showed a reduced capacity to colonize tomato roots. The effect of Tparo7-silencing on tomato plant responses was examined in greenhouse assays. The growth of plants colonized by the silenced transformants was reduced and the plants exhibited an increased susceptibility to B. cinerea in comparison with the responses observed for control plants. In addition, the plants turned yellowish and were defective in jasmonic acid- and ethylene-regulated signaling pathways which was seen by expression analysis of lipoxygenase 1 (LOX1), ethylene-insensitive protein 2 (EIN2) and pathogenesis-related protein 1 (PR-1) genes.

Objetivos:a. Estudiar el desarrollo de la comprensión lectora en alumnos de primer y segundo año de secundaria. b. Analizar el nivel de desarrollo de la comprensión de los alumnos de centros educativos estatales y no estatales en primer y segundo año de secundaria...

El objetivo del trabajo fue investigar en un puente ferroviario tipo cercha, metálico con 71m de longitud y 30 años de servicio, el avance del proceso corrosivo, sus causas y evaluar la posibilidad de rehabilitarlo. La metodología seguida fue la inspección, el estudio de la memoria descriptiva y con base a estos aspectos la realización de una serie de ensayos. También se evaluó el ambiente, esto es, temperatura, humedad, factor de humectación y velocidad del viento. En los elementos metálicos se observó una corrosión localizada en la parte inferior del puente y en la parte superior la estructura estaba en buen estado. Con respecto a los elementos de concreto armado se observó en los muros de apoyo ausencia de grietas y fisuras, sin embargo en los muros laterales se apreció un desplazamiento. El puente se puede rehabilitar, por tanto se refirieron los resultados a los ingenieros estructurales. Se recomienda sustituir todos los pernos de la zona inferior, reforzar las vigas inferiores y las dos vigas transversales extremas del puente; y se recomendó sustituir los apoyos por estar muy deteriorados.The object of the work was to investigate the damages by corrosion of a railroad bridge, to determine the advance of the corrosive process, its causes and to evaluate its possible rehabilitation. Its structure is type lauers, metalist with 71m of length and 30 years on service. The methodology was the inspection, the study of the descriptive memory of the bridge and with bases to these aspects the accomplishment of a series of tests. Also the atmosphere was evaluated, that is to say, temperature, humidity, factor of humectatión and wind speed. In the metallic elements a corrosion located in the inferior part of the bridge was observed, in the superior part the structure was observed in good state. With respect to the elements of reinforced concrete absence of cracks and fissures was observed in the support walls, nevertheless in the lateral walls was appraised a displacement. According to this evaluation the bridge can be rehabilitated. It was recommended to replace all bolt of the inferior zone, reinforcing the inferior beams of the segment and the two extreme cross-sectional beams of the bridge. The supports to be much deteriorated it were recommended to replace them.

The zebrafish is a model organism used to study organogenesis during vertebrate development; however epidermis development has been the focus of only a few studies. Thus, new methodologies to highlight and study epidermal cells could be valuable to deepen our understanding of skin development. Large-scale mutagenic screenings have already identified many zebrafish mutants, which are models for human developmental diseases, however only four epidermis mutants have been isolated. Novel screening techniques are needed to improve this collection. We designed and tested a novel freeze-crack technique to obtain, fix, and stain epidermal cells from 5 days postfertilization zebrafish larvae. Using commercially available fluorescent markers and differential interference contrast (DIC) microscopy, we were able to label and highlight subcellular structures such as microridges, cell boundaries, nuclei, and the Golgi complex from epidermis cells. Acquiring and processing epidermis samples from 15 to 75 larvae takes about 2–4 h, respectively. Therefore this method could be used as part of large-scale screenings. In addition, we present a more extensive protocol for antibody staining, which could be employed for more specific studies.

Aim. Our aim was (1) to determine the frequency of insulin resistance (IR) in patients with Duchenne/Becker muscular dystrophy (DMD/BMD), (2) to identify deleted exons of DMD gene associated with obesity and IR, and (3) to explore some likely molecular mechanisms leading to IR. Materials and Methods. In 66 patients with DMD/BMD without corticosteroids treatment, IR, obesity, and body fat mass were evaluated. Molecules involved in glucose metabolism were analyzed in muscle biopsies. Results show that 18.3%, 22.7%, and 68% were underweight, overweight, or obese, and with high adiposity, respectively; 48.5% and 36.4% presented hyperinsulinemia and IR, respectively. Underweight patients (27.3%) exhibited hyperinsulinemia and IR. Carriers of deletions in exons 45 (OR = 9.32; 95% CI = 1.16–74.69) and 50 (OR = 8.73; 95% CI = 1.17–65.10) from DMD gene presented higher risk for IR than noncarriers. We observed a greater staining of cytoplasmic aggregates for GLUT4 in muscle biopsies than healthy muscle tissue. Conclusion. Obesity, hyperinsulinemia, and IR were observed in DMD/BMD patients and are independent of corticosteroids treatment. Carriers of deletion in exons 45 or 50 from DMD gene are at risk for developing IR. It is suggested that alteration in GLUT4 in muscle fibers from DMD patients could be involved in IR.

We study the initial-boundary value problem for nonlinear pseudodifferential equations, on a half-line, $$displaylines{ u_{t}+mathcal{lambda}| u| ^{sigma}u+mathcal{L} u=0,quad(x,t)in{mathbb{R}^{+}}imes{mathbb{R}^{+}},cr u(x,0)=u_{0}(x),quad xin{mathbb{R}}^{+}, }$$ where $lambda>0$ and pseudodifferential operator $mathcal{L}$ is defined by the inverse Laplace transform. The aim of this paper is to prove the global existence of solutions and to find the main term of the asymptotic representation in the case of the large initial data.

In the title compound, C14H10ClNO2, obtained by the condensation of 4-chloroaniline and piperonal, the five-membered ring is almost planar (r.m.s. deviation = 0.023 Å) and the dihedral angle between the aromatic rings is 43.22 (14)°. In the crystal, a short O...Cl contact of 3.173 (2) Å is observed. The molecules are arranged into corrugated (010) layers.

Soft magnetic alloys at the nanoscale level have long generated a vivid interest as candidate materials for technological and biomedical purposes. Consequently, controlling the structure of bimetallic nanoparticles in order to optimize their magnetic properties, such as high magnetization and low coercivity, can significantly boost their potential for related applications. However, traditional synthesis methods stumble upon the long standing challenge of developing true nanoalloys with effective control over morphology and stability against oxidation. Herein, we report on a single-step approach to the gas phase synthesis of soft magnetic bimetallic iron aluminide nanoparticles, using a versatile co-sputter inert gas condensation technique. This method allowed for precise morphological control of the particles; they consisted of an alloy iron aluminide crystalline core (DO3 phase) and an alumina shell, which reduced inter-particle interactions and also prevented further oxidation and segregation of the bimetallic core. Remarkably, the as-deposited alloy nanoparticles show interesting soft magnetic properties, in that they combine a high saturation magnetization (170 emu/g) and low coercivity (less than 20 Oe) at room temperature. Additional functionality is tenable by modifying the surface of the particles with a polymer, to ensure their good colloidal dispersion in aqueous environments.

A partir de la preocupación por el aumento de la frecuencia de depresión y la disminución de la edad de las personas que padecen este tipo de problema, así como algunos indicadores que lo acompañan y que se encuentra dentro del concepto de desajuste psicosocial, surge la necesidad de estudiar dichos fenómenos en la población escolar. Objetivos: Demostrar la relación interdependiente de las variables ajuste psicosocial y depresión en escolares del nivel secundario de Lima Metropolitana, en función al tipo de colegio (estatal y particular) y género. Diseño: Es una investigación de tipo básica y de diseño descriptivo comparativo y correlacional. Material y método: La muestra estuvo constituida por 480 escolares de centros educativos estatales y particulares, cuyas edades oscilan entre los 12 y 17 años. Para la evaluación de la variable ajuste psicosocial, se utilizó el Inventario de Adaptación de Conducta de M. Victoria de la Cruz y Agustín Cordero, y para evaluar la variable depresión, se utilizó el Cuestionario de Depresión para niños y adolescentes de M. Lang y M. Tisher. El análisis estadístico derivó en primer lugar, en un análisis de validez y confiabilidad de las pruebas, y en segundo lugar, se realizó un análisis inferencial para la contrastación de las hipótesis planteadas. Resultados: Se ha encontrado que las dos pruebas utilizadas son altamente válidas y confiables.

El estudio de las Organizaciones No Gubernamentales estuvo dirigido a caracterizar la diversidad de grupos y asociaciones que bajo el termino genérico de ONGs existen en los municipios Maracaibo y San Francisco, los más poblados y relevantes en la vida política, económica, social y cultural del estado Zulia-Venezuela. Se planteó una investigación exploratoria y descriptiva. El resultado permitió reconocer a) Existe un crecimiento sostenido de las ONG en estos municipios: b) los sectores con mayor concentración son el de salud; educación; deporte y recreación; arte y cultura. c) Las instituciones que promueven más organizaciones son la iglesia y el Estado, lo que supone es este último caso una reducción de las funciones que le corresponden, además de la minimización de costos y conflictos laborales. d) Ambivalencia en la orientación de su funcionamiento: Algunas ONGs implementan prácticas próximas a la mercantilización de los servicios con lo cual legitiman estrategias del modelo económico neoliberal mientras otras contribuyen a fortalecer la democratización de los servicios públicos. Se concluye que el crecimiento y características de las ONGs en estos municipios estuvo vinculado en los noventa y comienzos de la década de 2000 por la aplicación de las políticas públicas neoliberales.

Seven species of aloricate planktonic ciliates were identified using protargol staining. Choreotrichida: Strombidinopsidae, Strombidinopsis elongata Song & Bradbury, 1998; Strobiliidae, Strobilidium epacrum Lynn & Montagnes, 1988 and Strombidiida: Strombidiidae, Strombidium capitatum (Leegaard, 1915) Kahl, 1932; S. emergens (Leegaard, 1915) Kahl, 1932; S. acutum Leegaard, 1915; S. dalum Lynn, Montagnes & Small, 1988 and Cyrtostrombidium longisomum Lynn & Gilron, 1993; they were collected from the inner zone of the Bahía Blanca estuary in the southern region of the Buenos Aires province, Argentina. These species represent new records to South America (Argentina).

The QT interval is a marker of ventricular repolarization. The increase of heterogeneity in the repolarization of the ventricles is associated with a higher risk for the appareance of malignant ventricular arrhytmias and it may be expressed by the dispersion of the QT interval. In practice, the dispersion of this interval may be defined as the difference between the maximum and the minimum QT in a standard EKG of 12 derivations, eventhough there are diverse methods to measure it. Areview of some fundamental aspects connected with the QT dispersion, its clinical expression, the cellular bases and the limitations of the method that may be useful to evaluate this important sign is made.

QT dispersion was evaluated among 31 patients: 10 carriers of unstable angina, 21 with acute myocardial infarction and a control group of sound individuals. All of them underwent electrocardiogram at 25 and 55 mm/s, with amplitudes of 1 and 2 mV on their arrival to the Emergency Department, and postthrombolysis (cases with infarction) at the 24 hours, 72 hours and 7 days. Those cases with angina had normal mean values. As regards infarction, the figures were signiificantly high in relation to the control group and to that with angina. There was a marked reduction of postthrombolysis figures in survivors and they were high in those who died. It is concluded that the mean figures of QT dispersion are normal in patients with angina and significantly higher among those with AMI. Thrombolysis reduces QT dispersion, excepting in the dead, where it is over 80 m/s.

For several years, DEAD box RNA helicase Vasa (DDX4) has been used as a bona fide germline marker in different organisms. C. elegans VBH-1 is a close homolog of the Vasa protein, which plays an important role in gametogenesis, germ cell survival and embryonic development. Here, we show that VBH-1 protects nematodes from heat shock and oxidative stress. Using the germline-defective mutant glp-4(bn2) we found that a potential somatic expression of vbh-1 might be important for stress survival. We also show that the VBH-1 paralog LAF-1 is important for stress survival, although this protein is not redundant with its counterpart. Furthermore, we observed that the mRNAs of the heat shock proteins hsp-1 and sip-1 are downregulated when vbh-1 or laf-1 are silenced. Previously, we reported that in C. elegans, VBH-1 was primarily expressed in P granules of germ cells and in the cytoplasm of all blastomeres. Here we show that during stress, VBH-1 co-localizes with CGH-1 in large aggregates in the gonad core and oocytes; however, VBH-1 aggregates do not overlap with CGH-1 foci in early embryos under the same conditions. These data demonstrate that, in addition to the previously described role for this protein in the germline, VBH-1 plays an important role during the stress response in C. elegans through the potential direct or indirect regulation of stress response mRNAs.

The once-dominant shallow reef-building coral Acropora palmata has suffered drastic geographical declines in the wider Caribbean from a disease epidemic that began in the late 1970s. At present there is a lack of quantitative data to determine whether this species is recovering over large spatial scales. Here, we use quantitative surveys conducted in 107 shallow-water reef sites between 2010 and 2012 to investigate the current distribution and abundance of A. palmata along the Mesoamerican Reef System (MRS). Using historical data we also explored how the distribution and abundance of this species has changed in the northern portion of the MRS between 1985 and 2010-2012. A. palmata was recorded in only a fifth of the surveyed reef sites in 2010-2012. In the majority of these reef sites the presence of A. palmata was patchy and rare. Only one site (Limones reef), in the northernmost portion of the MRS, presented considerably high A. palmata cover (mean: 34.7%, SD: 24.5%). At this site, the size-frequency distribution of A. palmata colonies was skewed towards small colony sizes; 84% of the colonies were healthy, however disease prevalence increased with colony size. A comparison with historical data showed that in the northern portion of the MRS, in 1985, A. palmata occurred in 74% of the 31 surveyed sites and had a mean cover of 7.7% (SD = 9.0), whereas in 2010-2012 this species was recorded in 48% of the sites with a mean cover of 2.9% (SD = 7.5). A. palmata populations along the MRS are failing to recover the distribution and abundance they had prior to the 1980s. Investigating the biological (e.g., population genetics) and environmental conditions (e.g., sources of stress) of the few standing reefs with relatively high A. palmata cover is crucial for the development of informed restoration models for this species.

El Renacimiento y la Reforma protestante dan lugar a una orientación totalmente divergentes entre los pensamientos occidental y oriental, y por lo mismo a culturas diferentes ya que "En la base de todo se reconoce la voluntad de actuar, de emprender, de dominar, de someter -para utilizarlas- las fuerzas naturales y las fuerzas humanas..."

The application of gel electrophoresis and numerical analysis of yeast soluble proteins analysis to the investigation of 12 oral yeast strains belonging to five species is described. It involves one-dimensional electrophoresis of SDS-solubilized whole-cell proteins using different culture media for the cultivation of the cells, integration densitometries in the areas of the gels and percentages of the proteins extraction. These extracts were prepared from four isolates of Candida albicans, two of C. tropicalis, C. guilliermondii, C. parapsilosis and C. krusei. The extracts from whole-cells proteins using different culture media for the cultivation of the cells were fractionated by slab electrophoresis using a discontinuous buffer system. The corresponding patterns showed at least 36 polypeptides in the range of 14.4-200 kDa. Different isolates of each species were clearly different in each of the five species. The data obtained suggest that different nutritional compositions led to the expression of different proteins derived from alternatives metabolic pathways expressed by the electrophoretic profiles. The construction of a database of protein fingerprints and numerical analysis based on such data, may have some implications in the classification and identification of such species with epidemiological, ecological and taxonomic purposes. A well defined or synthetic culture media seems to be much properly.

During the Late Pleistocene, Mexico had a richer fauna than today with many different forms of megafauna that are now extinct. However, the ecosystems they inhabited and the particular ecological niches that they occupied are still poorly understood. Most of the findings of Pleistocene megafauna have been in alluvial deposits that present rich opportunities for paleoecological studies using paleopedological records. Floodplain paleosols commonly are poorly developed. However, micromorphological analysis provides information about the grade of development of the soil at a microscale, discriminating between genetic and sedimentary processes; thus helping in the identification of the environmental setting in which they formed. We analyzed the micromorphology of six pedogenetic units in the sequences of Santa Cruz Nuevo and Axamilpa, in the south of Puebla, and Huexoyucan, in the state of Tlaxcala. These pedosequences correspond to the second half of marine isotopic stage 3 (MIS3), MIS2 and the early Holocene. All studied units are characterized by strong pigmentation with dark humus. The micromorphological analysis of MIS3 paleosols reveals aquatic conditions with evidence of freshwater biota and microlamination as well as pedogenetic features of hydrogenic carbonate precipitation and redoximorphic processes. The dark paleosols of MIS2 and the early Holocene demonstrate signs of stronger coprogenic aggregation, weathering and fewer gleyic features. Comparison with modern soils shows that the latter were formed under better-drained, aerated conditions that exclude redoximorphic processes. We conclude that the dark colored Pleistocene paleosol units are indicative of different paleo-landscapes: wetlands in the MIS3 and moist meadows in MIS2 early Holocene. The swampy ecosystems could play an important role as a megafauna habitat.En el Pleistoceno Tardío, México tenía una diversidad faunística más rica que en la actualidad, con diferentes formas de megafauna, hoy extinta. Sin embargo, los ecosistemas que habitaron y determinados nichos ecológicos que ocupaban son poco conocidos. Los hallazgos más numerosos de la megafauna del Pleistoceno han sido en depósitos aluviales, los cuales son registros paleoecológicos importantes que representan una excelente oportunidad para ser estudiados. Los paleosuelos aluviales regularmente son poco desarrollados, sin embargo, el análisis micromorfológico proporciona información relevante sobre el grado de desarrollo del suelo a una microescala, permitiendo discriminar entre los procesos edafogenéticos y sedimentarios; ayudando con ello a la identificación de la configuración del medio ambiente en el que se formaron. Nosotros analizamos la micromofología de seis unidades edafogenéticas en las secuencias de Santa Cruz Nuevo y Axamilpa, en el sur de Puebla y Huexoyucan, en el estado de Tlaxcala. Estas edafosecuencias corresponden a la segunda mitad de la etapa isotópica marina 3 (MIS3), etapa isotópica marina 2 MIS2 y al Holoceno Temprano. Todas las unidades estudiadas se caracterizan por una fuerte pigmentación con humus oscuro. El análisis micromorfológico de los paleosuelos de MIS3 revela condiciones acuáticas con evidencias de biota de agua dulce, como también microlaminaciones de precipitación de carbonatos hidrogénicos y procesos redoximórficos. Los paleosuelos oscuros de MIS2 y el Holoceno Temprano muestran fuerte agregación coprogénica, intemperismo y pocos rasgos gleycos, presentando fuertes diferencias con los suelos modernos. Los suelos modernos se formaron en condiciones aireadas, con un mejor drenaje que excluyen los procesos redoximórficos. Llegamos a la conclusión de que las unidades de paleosuelos del Pleistoceno de color oscuro son indicativos de diferentes paleopaisajes: humedales pantanosos en la MIS3 y praderas húmedas desde MIS2 hasta el Holoceno Temprano. Los ecosistemas pantanosos podrían representar un importante hábitat para la megafauna del Pleistoceno.No Pleistocénico tardio, o México apresentava uma diversidade faunística mais rica que na actualidade, com diferentes formas de megafauna, hoje extinta. Sem dúvida, os ecossistemas que habitaram e determinados nichos ecológicos que ocupavam são pouco conhecidos. A maioria dos numerosos achados da megafauna do Pleistocénico foi em depósitos aluviais, que representam registos importantes paleoecológicos pelo que constituem uma excelente oportunidade para serem estudados. Os paleosolos aluviais são geralmente pouco desenvolvidos, pelo que a análise micromorfológica proporciona, sem dúvida, informação relevante sobre o grau de desenvolvimento do solo à microescala, permitindo distinguir entre os processos pedogenéticos e sedimentares, ajudando com isso à identificação da configuração do ambiente em que se formaram. No nosso estudo, procedeu-se à análise da micromofología de seis unidades pedogenéticas nas sequências de Santa Cruz Nuevo e Axamilpa, no Sul de Puebla e Huexoyucan, no estado de Tlaxcala. Estas pedosequências correspondem à segunda metade da etapa isotópica marinha 3 (MIS3), etapa isotópica marinha 2 MIS2 e ao Holocénico Inicial. Todas as unidades estudadas caracterizavam-se por uma forte pigmentação com húmus escuro. A análise micromorfológica dos paleosolos de MIS3 revelou condições aquáticas com evidências de biota de água doce, bem como microlaminações de precipitação de carbonatos hidrogenados e processos redoximórficos. Los paleosolos escuros de MIS2 e o Holocénico Inicial apresentavam forte agregação cuprogénica, intemperismo e poucas características gleycos, apresentando grandes diferenças para os solos modernos. Os solos modernos formaram-se em condições de arejamento, com uma melhor drenagem que excluem os processos redoximórficos. Deste estudo concluímos que as unidades de paleosolos do Pleistocénico de cor escura são indicativas de diferentes paleopaisagens: zonas húmidas pantanosas na MIS3 e prados húmidos desde MIS2 até ao Holocénico Inicial. Os ecossistemas pantanosos poderão representar um importante habitat para a megafauna do Pleistocénico.

Se evaluó la dispersión del QT en 31 pacientes: 10 portadores de angina inestable, 21 de infarto miocárdico agudo y en un grupo control de sujetos sanos. A todos se les realizó un electrocardiograma a 25 y 50 mm/s, con amplitudes de 1 y 2 mV, a su llegada al Cuerpo de Guardia, postrombólisis (casos con infarto) y a las 24, 72 h y 7 días. Los casos con angina tuvieron valores medios normales. En el infarto, las cifras fueron significativamente altas con relación al grupo control y al de angina. Las cifras postrombólisis disminuyeron significativamente en los sobrevivientes y se mantuvieron elevadas en los fallecidos. Concluimos que las cifras medias de dispersión del QT son normales en los pacientes con angina y son significativamente mayores en los casos de IMA. La trombólisis reduce la dispersión del QT, excepto en los fallecidos donde excede los 80 ms. QT dispersion was evaluated among 31 patients: 10 carriers of unstable angina, 21 with acute myocardial infarction and a control group of sound individuals. All of them underwent electrocardiogram at 25 and 55 mm/s, with amplitudes of 1 and 2 mV on their arrival to the Emergency Department, and postthrombolysis (cases with infarction) at the 24 hours, 72 hours and 7 days. Those cases with angina had normal mean values. As regards infarction, the figures were signiificantly high in relation to the control group and to that with angina. There was a marked reduction of postthrombolysis figures in survivors and they were high in those who died. It is concluded that the mean figures of QT dispersion are normal in patients with angina and significantly higher among those with AMI. Thrombolysis reduces QT dispersion, excepting in the dead, where it is over 80 m/s.

El intervalo QT es un marcador del estado de la repolarización ventricular. El aumento de la heterogeneidad en la repolarización de los ventrículos, se asocia a un mayor riesgo para la aparición de arritmias ventriculares malignas y puede ser expresado a través de la dispersión del intervalo QT. En la práctica, la dispersión de este intervalo puede ser definida como la diferencia entre el QT máximo y mínimo en un ECG estándar de 12 derivaciones, aunque existen diversos métodos para realizar su medición. En este artículo se realiza una revisión de algunos aspectos fundamentales relacionados a la dispersión del QT, su expresión clínica, las bases celulares y las limitaciones del método; que pueden resultar de utilidad en la evaluación de este importante signo. The QT interval is a marker of ventricular repolarization. The increase of heterogeneity in the repolarization of the ventricles is associated with a higher risk for the appareance of malignant ventricular arrhytmias and it may be expressed by the dispersion of the QT interval. In practice, the dispersion of this interval may be defined as the difference between the maximum and the minimum QT in a standard EKG of 12 derivations, eventhough there are diverse methods to measure it. Areview of some fundamental aspects connected with the QT dispersion, its clinical expression, the cellular bases and the limitations of the method that may be useful to evaluate this important sign is made.

¿Que pensaron los hombres sobre las mujeres durante la segunda mitad del siglo XIX? ¿Cómo y por qué lo pensaron? La respuesta a estas cuestiones es el objetivo principal de Bram Dijkstra en su libro Ídolos de perversidad, objetivo que el autor explicita ya en el mismo prólogo de la obra.

The asymmetric unit of the title hydrated complex salt, (C18H14N5)2[Pt(CN)4]·4H2O, consists of one 2-[2,5-bis(pyridin-2-yl)-1H-imidazol-4-yl]pyridinium cation, half a tetracyanidoplatinate(II) dianion, which is located about a crystallographic inversion center, and two water molecules of crystallization. The PtII atom has a square-planar coordination environment, with Pt—CCN distances of 1.992 (4) and 2.000 (4) Å. In the cation, there is an N—H...N hydrogen bond linking adjacent pyridinium and pyridine rings in positions 4 and 5. Despite this, the organic component is non-planar, as shown by the dihedral angles of 10.3 (2), 6.60 (19) and 15.66 (18)° between the planes of the central imidazole ring and the pyridine/pyridinium substituents in the 2-, 4- and 5-positions. In the crystal, cations and anions are linked via O—H...O, O—H...N and N—H...O hydrogen bonds, forming a three-dimensional network. Additional π–π, C—H...O and C—H...N contacts provide stabilization to the crystal lattice.

Plasma cells produce and secrete massive amounts of disulfide-containing antibodies. To accommodate this load on the secretory machinery, the differentiation of resting B cells into antibody-secreting plasma cells is accompanied by a preferential expansion of the secretory compartments of the cells and by an up-regulation of enzymes involved in redox regulation and protein folding. We have quantified the absolute levels of protein thiols, protein disulfides, and glutathionylated proteins in whole cells. The results show that while the global thiol-disulfide state is affected to some extent by the differentiation, steady-state levels of glutathionylated protein thiols are less than 0.3% of the total protein cysteines, even in fully differentiated cells, and the overall protein redox state is not affected until late in differentiation, when large-scale IgM production is ongoing. A general expansion of the ER does not affect global protein redox status until an extensive production of cargo proteins has started.

BACKGROUND: Influenza viruses display a high mutation rate and complex evolutionary patterns. Next-generation sequencing (NGS) has been widely used for qualitative and semi-quantitative assessment of genetic diversity in complex biological samples. The "deep sequencing" approach, enabled by the enormous throughput of current NGS platforms, allows the identification of rare genetic viral variants in targeted genetic regions, but is usually limited to a small number of samples. METHODOLOGY AND PRINCIPAL FINDINGS: We designed a proof-of-principle study to test whether redistributing sequencing throughput from a high depth-small sample number towards a low depth-large sample number approach is feasible and contributes to influenza epidemiological surveillance. Using 454-Roche sequencing, we sequenced at a rather low depth, a 307 bp amplicon of the neuraminidase gene of the Influenza A(H1N1) pandemic (A(H1N1)pdm) virus from cDNA amplicons pooled in 48 barcoded libraries obtained from nasal swab samples of infected patients (n = 299) taken from May to November, 2009 pandemic period in Mexico. This approach revealed that during the transition from the first (May-July) to second wave (September-November) of the pandemic, the initial genetic variants were replaced by the N248D mutation in the NA gene, and enabled the establishment of temporal and geographic associations with genetic diversity and the identification of mutations associated with oseltamivir resistance. CONCLUSIONS: NGS sequencing of a short amplicon from the NA gene at low sequencing depth allowed genetic screening of a large number of samples, providing insights to viral genetic diversity dynamics and the identification of genetic variants associated with oseltamivir resistance. Further research is needed to explain the observed replacement of the genetic variants seen during the second wave. As sequencing throughput rises and library multiplexing and automation improves, we foresee that the approach presented here can be scaled up for global genetic surveillance of influenza and other infectious diseases.

The synthesis of four amphiphilic organometallic complexes with the general formula RC = M(CO)5NH(CH2)15CH3, where R is a ferrocenyl 2(a-b) or a phenyl 4(a-b) group as a donor moiety and a Fischer carbene of chromium (0) or tungsten (0) as an acceptor group, are reported. These four push-pull systems formed Langmuir (L) monolayers at the air-water interface, which were characterized by isotherms of surface pressure versus molecular area and compression/expansion cycles (hysteresis curves); Brewster angle microscopic images were also obtained. By using the Langmuir–Blodgett (LB) method, molecular monolayers were transferred onto glass substrates forming Z-type multilayers. LB films were characterized through ultraviolet-visible spectroscopy, atomic force microscopy and X-ray diffraction techniques. Results indicated that films obtained from 2b complex [(Ferrocenyl)(hexadecylamine)methylidene] pentacarbonyl tungsten (0) are the most stable and homogeneous; due to their properties, these materials may be incorporated into organic electronic devices.

Sterols transport and distribution are essential processes in all multicellular organisms. Survival of the nematode Caenorhabditis elegans depends on dietary absorption of sterols present in the environment. However the general mechanisms associated to sterol uptake in nematodes are poorly understood. In the present work we provide evidence showing that a previously uncharacterized transmembrane protein, designated Cholesterol Uptake Protein-1 (ChUP-1), [corrected] is involved in dietary cholesterol uptake in C. elegans. Animals lacking ChUP-1 [corrected] showed hypersensitivity to cholesterol limitation and were unable to uptake cholesterol. A ChUP-1-GFP [corrected] fusion protein colocalized with cholesterol-rich vesicles, endosomes and lysosomes as well as the plasma membrane. Additionally, by FRET imaging, a direct interaction was found between the cholesterol analog DHE and the transmembrane "cholesterol recognition/interaction amino acid consensus" (CRAC) motif present in C. elegans ChUP-1. [corrected]. In-silico analysis identified two mammalian homologues of ChUP-1. [corrected]. Most interestingly, CRAC motifs are conserved in mammalian ChUP-1 [corrected] homologous. Our results suggest a role of ChUP-1 [corrected] in cholesterol uptake in C. elegans and open up the possibility for the existence of a new class of proteins involved in sterol absorption in mammals.

To study the impacts of selective logging behaviors on a forest landscape, we developed an intermediate-scale spatial model to link cross-scale interactions of timber harvesting, a fine-scale human activity, with coarse-scale landscape impacts. We used the Lotka-Volterra predator-prey model with Holling’s functional response II to simulate selective logging, coupled with a cellular automaton model to simulate logger mobility and forest fragmentation. Three logging scenarios were simulated, each varying in timber harvesting preference and logger mobility. We quantified forest resilience by evaluating (1) the spatial patterns of forest fragmentation, (2) the time until the system crossed a threshold into a deforested state, and (3) recovery time. Our simulations showed that logging behaviors involving decisions made about harvesting timber and mobility can lead to different spatial patterns of forest fragmentation. They can, together with forest management practices, significantly delay or accelerate the transition of a forest landscape to a deforested state and its return to a recovered state. Intermediate-scale models emerge as useful tools for understanding cross-scale interactions between human activities and the spatial patterns that are created by anthropogenic land use.

Se realizó un trabajo descriptivo retrospectivo en el Policlínico I de Caibarién con las embarazadas que tuvieron hijos con un peso inferior a 3000 g en el período comprendido entre enero y diciembre de 2001, con el fin de conocer las causas del bajo peso al nacer. Para realizar este estudio se confeccionaron dos encuestas, con el objetivo de determinar los factores maternos biológicos y sociales, la edad gestacional en el momento del parto, las características del nacimiento y si se produjeron complicaciones o fallecimientos; se valoró la incorporación a los comedores obreros y los ingresos en el hogar materno. Con estos datos, se concluyó que entre los factores de riesgo maternos biológicos predominaron: la anemia, la ganancia de peso menor de 8 kg y la sepsis vaginal; los factores sociales más frecuentes fueron: madre fumadora, ama de casa y no estar incorporada a las actividades educativas. No hubo una adecuada utilización del hogar materno ni de los comedores obreros en el riesgo nutricional.

Septate junctions (SJs) display a unique ultrastructural morphology with ladder-like electron densities that are conserved through evolution. Genetic and molecular analyses have identified a highly conserved core complex of SJ proteins consisting of three cell adhesion molecules Neurexin IV, Contactin, and Neuroglian, which interact with the cytoskeletal FERM domain protein Coracle. How these individual proteins interact to form the septal arrays that create the paracellular barrier is poorly understood. Here, we show that point mutations that map to specific domains of neurexin IV lead to formation of fewer septae and disorganization of SJs. Consistent with these observations, our in vivo domain deletion analyses identified the first Laminin G-EGF-Laminin G module in the extracellular region of Neurexin IV as necessary for the localization of and association with Contactin. Neurexin IV protein that is devoid of its cytoplasmic region is able to create septae, but fails to form a full complement of SJs. These data provide the first in vivo evidence that specific domains in Neurexin IV are required for protein-protein interactions and organization of SJs. Given the molecular conservation of SJ proteins across species, our studies may provide insights into how vertebrate axo-glial SJs are organized in myelinated axons.

Coral-grounds are reef communities that colonize rocky substratum but do not form framework or three-dimensional reef structures. To investigate why, we used video transects and underwater photography to determine the composition, structure and status of a coral-ground community located on the edge of a rocky terrace in front of a tourist park, Xcaret, in the northern Mesoamerican Reef tract, Mexico. The community has a relatively low coral, gorgonian and sponge cover (40%). We recorded 23 species of Scleractinia, 14 species of Gorgonacea and 30 species of Porifera. The coral community is diverse but lacks large coral colonies, being dominated instead by small, sediment-tolerant, and brooding species. In these small colonies, the abundance of potentially lethal interactions and partial mortality is high but decreases when colonies are larger than 40 cm. Such characteristics are consistent with an environment control whereby storm waves periodically remove larger colonies and elevate sediment flux. The community only survives these storm conditions due to its slope-break location, which ensures lack of burial and continued local recruitment. A comparison with similar coral-ground communities in adjacent areas suggests that the narrow width of the rock terrace hinders sediment stabilization, thereby ensuring that communities cannot escape bottom effects and develop into three-dimensional reef structures on geological time scales.

Countries could use the monitoring of drug resistance in malaria parasites as an effective early warning system to develop the timely response mechanisms that are required to avert the further spread of malaria. Drug resistance surveillance is essential in areas where no drug resistance has been reported, especially if neighbouring countries have previously reported resistance. Here, we present the results of a four-year surveillance program based on the sequencing of the pfcrt gene of Plasmodium falciparum populations from endemic areas of Honduras. All isolates were susceptible to chloroquine, as revealed by the pfcrt “CVMNK” genotype in codons 72-76.