(Table 1) Chemical composition of segregations and groundmass seperates of ODP Leg 135 samples

Concentrations of dark-colored, highly vesicular, quench-textured mesostasis occur commonly in volcanic rocks drilled in the Lau Basin during Leg 135. These segregations occur as veins, patches, and vesicle linings in rocks with 49%-54% SiO2. The segregations are depleted in Mg, Ca, Al, Sc, Ni, and Cr and enriched in Ti, Ba, Y, and Zr compared to the groundmass with which they occur. Many of the segregations are unusually enriched in copper. The elemental variations show that the segregations are residual liquids produced by 12%-55% crystallization of plagioclase and clinopyroxene, with minor olivine, opaques, or orthopyroxene from the groundmass melt. The liquids forming the segregations are mobilized and emplaced in earlier formed vesicles during the rapid crystallization of the groundmass. The dominant process in this mobilization and emplacement is volatile exsolution from crystallizing melts constrained by a rigid crystalline framework. This exsolution produces significant overpressures within the late-stage melts; the overpressure drives the residual melts through the walls of the older vesicles, along planes of weakness, and into voids. This mechanism is consistent with the occurrence of bimodal vesicle populations in many of the host lavas.

A monovalent chimpanzee adenovirus Ebola vaccine boosted with MVA

BACKGROUND The West African outbreak of Ebola virus disease that peaked in 2014 has caused more than 11,000 deaths. The development of an effective Ebola vaccine is a priority for control of a future outbreak. METHODS In this phase 1 study, we administered a single dose of the chimpanzee adenovirus 3 (ChAd3) vaccine encoding the surface glycoprotein of Zaire ebolavirus (ZEBOV) to 60 healthy adult volunteers in Oxford, United Kingdom. The vaccine was administered in three dose levels — 1×1010 viral particles, 2.5×1010 viral particles, and 5×1010 viral particles — with 20 participants in each group. We then assessed the effect of adding a booster dose of a modified vaccinia Ankara (MVA) strain, encoding the same Ebola virus glyco- protein, in 30 of the 60 participants and evaluated a reduced prime–boost interval in another 16 participants. We also compared antibody responses to inactivated whole Ebola virus virions and neutralizing antibody activity with those observed in phase 1 studies of a recombinant vesicular stomatitis virus–based vaccine expressing a ZEBOV glycoprotein (rVSV-ZEBOV) to determine relative potency and assess durability. RESULTS No safety concerns were identified at any of the dose levels studied. Four weeks after immunization with the ChAd3 vaccine, ZEBOV-specific antibody responses were similar to those induced by rVSV-ZEBOV vaccination, with a geometric mean titer of 752 and 921, respectively. ZEBOV neutralization activity was also similar with the two vaccines (geo- metric mean titer, 14.9 and 22.2, respectively). Boosting with the MVA vector increased virus-specific antibodies by a factor of 12 (geometric mean titer, 9007) and increased glycoprotein-specific CD8+ T cells by a factor of 5. Significant increases in neutralizing antibodies were seen after boosting in all 30 participants (geometric mean titer, 139; P<0.001). Virus-specific antibody responses in participants primed with ChAd3 remained positive 6 months after vaccination (geometric mean titer, 758) but were significantly higher in those who had received the MVA booster (geometric mean titer, 1750; P<0.001). CONCLUSIONS The ChAd3 vaccine boosted with MVA elicited B-cell and T-cell immune responses to ZEBOV that were superior to those induced by the ChAd3 vaccine alone. (Funded by the Wellcome Trust and others; ClinicalTrials.gov number, NCT02240875.)

LtpD is a novel legionella pneumophila effector that binds phosphatidylinositol 3-phosphate and inositol monophosphatase IMPA1

The Dot/Icm type IV secretion system (T4SS) of Legionella pneumophila is crucial for the pathogen to survive in protozoa and cause human disease. Although more than 275 effector proteins are delivered into the host cell by the T4SS, the function of the majority is unknown. Here we have characterized the Dot/Icm effector LtpD. During infection, LtpD localized to the cytoplasmic face of the membrane of the Legionella-containing vacuole (LCV). In A549 lung epithelial cells, ectopically expressed LtpD localized to large vesicular structures that contained markers of endosomal compartments. Systematic analysis of LtpD fragments identified an internal 17-kDa fragment, LtpD_471-626, which was essential for targeting ectopically expressed LtpD to vesicular structures and for the association of translocated LtpD with the LCV. LtpD_471-626 bound directly to phosphatidylinositol 3-phosphate [PtdIns(3)P] in vitro and colocalized with the PtdIns(3)P markers FYVE and SetA in cotransfected cells. LtpD was also found to bind the host cell enzyme inositol (myo)-1 (or 4)-monophosphatase 1, an important phosphatase involved in phosphoinositide production. Analysis of the role of LtpD in infection showed that LtpD is involved in bacterial replication in THP-1 macrophages, the larvae of Galleria mellonella, and mouse lungs. Together, these data suggest that LtpD is a novel phosphoinositide- binding L. pneumophila effector that has a role in intracellular bacterial replication. © 2013, American Society for Microbiology.

Estudio experimental sobre la combinación temporal de resultados en el reconocimiento de caras con secuencias de video

[ES]Se ha comprobado que la combinación de los resultados de clasi cación de varias imágenes de una secuencia mejora la probabilidad de acierto en el problema del reconocimiento de caras. No obstante, queda por dilucidar qué método de agregación temporal de los resultados es el más apropiado para cada caso concreto. En sistemas prácticos el método de combinación debe además ser simple para no consumir mucho tiempo de cómputo, teniendo en cuenta que el sistema tendrá otras etapas de proceso con una latencia relativamente alta. En este trabajo se describe un estudio experimental de varios métodos de combinación...

Limiting glutamate transmission in a Vglut2-expressing subpopulation of the subthalamic nucleus is sufficient to cause hyperlocomotion

The subthalamic nucleus (STN) is a key area of the basal ganglia circuitry regulating movement. We identified a subpopulation of neurons within this structure that coexpresses Vglut2 and Pitx2, and by conditional targeting of this subpopulation we reduced Vglut2 expression levels in the STN by 40%, leaving Pitx2 expression intact. This reduction diminished, yet did not eliminate, glutamatergic transmission in the substantia nigra pars reticulata and entopeduncular nucleus, two major targets of the STN. The knock-out mice displayed hyperlocomotion and decreased latency in the initiation of movement while preserving normal gait and balance. Spatial cognition, social function, and level of impulsive choice also remained undisturbed. Furthermore, these mice showed reduced dopamine transporter binding and slower dopamine clearance in vivo, suggesting that Vglut2-expressing cells in the STN regulate dopaminergic transmission. Our results demonstrate that altering the contribution of a limited population within the STN is sufficient to achieve results similar to STN lesions and high-frequency stimulation, but with fewer side effects.

Increased hippocampal excitability and impaired spatial memory function in mice lacking VGLUT2 selectively in neurons defined by tyrosine hydroxylase promoter activity

Three populations of neurons expressing the vesicular glutamate transporter 2 (Vglut2) were recently described in the A10 area of the mouse midbrain, of which two populations were shown to express the gene encoding, the rate-limiting enzyme for catecholamine synthesis, tyrosine hydroxylase (TH).One of these populations (‘‘TH– Vglut2 Class1’’) also expressed the dopamine transporter (DAT) gene while one did not ("TH–Vglut2 Class2"), and the remaining population did not express TH at all ("TH-Vglut2-only"). TH is known to be expressed by a promoter which shows two phases of activation, a transient one early during embryonal development, and a later one which gives rise to stable endogenous expression of the TH gene. The transient phase is, however, not specific to catecholaminergic neurons, a feature taken to advantage here as it enabled Vglut2 gene targeting within all three A10 populations expressing this gene, thus creating a new conditional knockout. These knockout mice showed impairment in spatial memory function. Electrophysiological analyses revealed a profound alteration of oscillatory activity in the CA3 region of the hippocampus. In addition to identifying a novel role for Vglut2 in hippocampus function, this study points to the need for improved genetic tools for targeting of the diversity of subpopulations of the A10 area

Étude des projections axonales sérotoninergiques dans un modèle murin de la maladie de Parkinson et des dyskinésies induites par la lévodopa

OBJECTIFS: La libération de dopamine par les afférences à sérotonine (5-HT) du striatum constitue un déterminant pré-synaptique important des dyskinésies induites par la L-Dopa (DILs), un effet délétère du traitement pharmacologique de la maladie de Parkinson. En effet, les axones 5-HT seraient en mesure de libérer de façon non-physiologique de la dopamine lorsque la L-Dopa est administrée au patient, contribuant ainsi à l’expression des DILs. Certaines afférences striatales 5-HT contiennent un transporteur vésiculaire du glutamate (VGluT3) et nous croyons que sa présence puisse avoir un effet synergique sur la libération de dopamine. L’objectif général de ce mémoire est donc d’évaluer la quantité de VGluT3 présent au sein des axones 5-HT et de mesurer son implication dans l’expression des DILs. MÉTHODES : Dix-huit souris C57/Bl6 ont été séparées en trois groupes expérimentaux. Douze souris ont reçu une injection intracérébrale de 6- hydroxydopamine (6-OHDA) dans le faisceau prosencéphalique médian afin de léser les afférences dopaminergiques du striatum. Six souris lésées ont reçu des injections systémiques de L-Dopa (12 jours, 1 fois/jour). Six autres souris ont reçu une injection intracérébrale du véhicule afin de servir de contrôle. La sévérité des mouvements involontaires anormaux induits par la L-Dopa (équivalent des dyskinésies) a été quantifiée selon une échelle reconnue. Un double marquage en immunofluorescence pour le transporteur membranaire de la 5-HT (SERT) et le VGluT3 a permis d’évaluer la densité des varicosités SERT+ et SERT+/VGluT3+ dans le striatum dorsal et de comparer ces données entre les trois groupes expérimentaux. RÉSULTATS: Chez les trois groupes de souris, un faible pourcentage des varicosités axonales 5-HT sont également VGluT3+. Ces varicosités doublement marquées sont souvent retrouvées sur une même branche axonale. Aucune différence significative n’a été observée entre les trois groupes expérimentaux en ce qui a trait à la proportion de varicosités SERT+ qui contiennent le VGluT3+. CONCLUSION: Nos données expérimentales ne nous permettent pas de conclure que la densité des varicosités axonales SERT+ ou SERT+/VGluT3+ au sein du striatum dorsal varie en fonction de la sévérité des mouvements involontaires anormaux induits par l’administration de L-Dopa.

Características clínicas y epidemiológicas del neumotórax en personas de 18 años y más: Hospital Vicente Corral Moscoso y Teófilo Dávila de Machala, 2007-2011

Se realizó un estudio descriptivo- retrospectivo desde enero de 2007 a diciembre del 2011. El universo estuvo constituido por los pacientes de 18 años y más con diagnóstico de Neumotórax, internados en los departamentos de cirugía del Hospital Regional Vicente Corral Moscoso y Hospital Teófilo Dávila. Para el levantamiento de la información se utilizó un formulario previamente diseñado. Los datos se transcribieron de las historias clínicas a los formularios respectivos. Resultados: Se incluyeron 73 pacientes del HTD y 52 del HVCM, el neumotórax de mayor prevalencia fue el traumático con el 85.6% de los casos, izquierdo en el 54.4%; las características clínicas de mayor relevancia fueron: dolor moderado 40.8%; taquicardia 15.2%; desviación de la tráquea hacia la derecha 32.8%; distención de las venas del cuello 38.4%; hipersonoridad 76.8%; murmullo vesicular disminuido 80%; disnea 99.2%; cianosis 22.4%; los método diagnósticos presentaron la siguiente prevalencia: radiografía de tórax 100%; tomografía 27.2% y resonancia en el 0.8% de los casos; el tratamiento fue en el 16% toracocentesis con aspiración de aguja y en el 100% tubo de tórax. La media de días de hospitalización fue de 5 días y la mortalidad fue del 10.4%.- Conclusiones: Se registraron diferencias estadísticamente significativas entre ambas instituciones en las características clínicas en cuanto a la procedencia, intensidad del dolor, frecuencia cardiaca, murmullo vesicular disminuido y presentación de cianosis. Además se evidencia una alta mortalidad.au

Dermatitis herpetiforme como carta de presentación de la enfermedad celíaca

RESUMEN: La Dermatitis Herpetiforme (DH) es una enfermedad ampollar autoinmune (EAI) que corresponde a la manifestación cutánea de la Enfermedad Celíaca (EC), más precisamente de la intolerancia al gluten. Clínicamente se manifiesta como una erupción papulo-vesicular pruriginosa, topografiada fundamentalmente en superficies de extensión de extremidades. El diagnóstico se realiza mediante el estudio histopatológico de piel lesional e inmunofluorescencia directa (IFD) de piel perilesional, la cual muestra hallazgos característicos. En su patogenia intervienen factores genéticos, inmunológicos, y ambientales. El tratamiento de elección es la dieta libre de gluten (DLG) y la Dapsona. Se ha reportado una asociación cercana al 15% entre la afectación cutánea e intestinal, no existe hasta el momento ningún estudio prospectivo que muestre la frecuencia real de EC en pacientes con DH

Single-molecule fluorescence resonance energy transfer study of SNARE-mediated membrane fusion

This is a comprehensive study of protein-mediated membrane fusion through single-molecule fluorescence resonance energy transfer (smFRET). Membrane fusion is one of the important cellular processes by which two initially distinct lipid bilayers merge their hydrophobic cores, resulting in one interconnected structure. For example, exocytosis, fertilization of an egg by a sperm and communication between neurons are a few among many processes that rely on some form of fusion. Proteins called soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) play a central role in fusion processes which is also regulated by many accessory proteins, such as synaptotagmin, complexin and Munc18. By a new lipid mixing method at the single-vesicle level, we are able to accurately detect different stages of SNARE-mediated membrane fusion including docking, hemi and full fusion via FRET value of single donor/acceptor vesicle pair. Through this single-vesicle lipid mixing assay, we discovered the vesicle aggregation induced by C2AB/Ca2+, the dual function of complexin, and the fusion promotion role of Munc18/SNARE-core binding mode. While this new method provides the information regarding the extent of the ensemble lipid mixing, the fusion pore opening between two vesicular cavities and the interaction between proteins cannot be detected. In order to overcome these limitations, we then developed a single-vesicle content mixing method to reveal the key factor of pore expansion by detecting the FRET change of dual-labeled DNA probes encapsulated in vesicles. Through our single-vesicle content mixing assay, we found the fusion pore expansion role of yeast SNAREs as well as neuronal SNAREs plus synaptotagmin 1.

Caso imagiológico

Introdução: A tosse constitui um dos principais motivos de consulta médica e, apesar de na maioria dos casos ser de etiologia vírica ou alérgica, por vezes surgem diagnósticos inesperados. Caso Clínico: Criança do sexo feminino, 19 meses, sem antecedentes relevantes. Recorreu ao Serviço de Urgência por tosse produtiva há 3 semanas e rinorreia serosa, sem febre. Noção materna de dificuldade respiratória e recusa alimentar parcial. À admissão, polipneica, com tiragem subcostal e gemido expiratório. Auscultatoriamente, murmúrio vesicular globalmente diminuído, tempo expiratório aumentado e sibilos dispersos. Analiticamente sem alterações. A radiografia torácica evidenciou volumosa imagem quística no hemitórax direito. A TC to- rácica documentou estômago intratorácico. Foi submetida a laparoscopia que constatou hérnia do hiato paraesofágica. Após Fundoplicatura de Nissen ficou assintomática. Discussão: A hérnia do hiato é rara em idade Pediátrica, tendo sido um achado inesperado no caso clínico descrito. Consideramos assim que, apesar da sua raridade, as anomalias anatómicas devem ser consideradas no diagnóstico diferencial da tosse persistente.

Limiting glutamate transmission in a Vglut2-expressing subpopulation of the subthalamic nucleus is sufficient to cause hyperlocomotion

The subthalamic nucleus (STN) is a key area of the basal ganglia circuitry regulating movement. We identified a subpopulation of neurons within this structure that coexpresses Vglut2 and Pitx2, and by conditional targeting of this subpopulation we reduced Vglut2 expression levels in the STN by 40%, leaving Pitx2 expression intact. This reduction diminished, yet did not eliminate, glutamatergic transmission in the substantia nigra pars reticulata and entopeduncular nucleus, two major targets of the STN. The knock-out mice displayed hyperlocomotion and decreased latency in the initiation of movement while preserving normal gait and balance. Spatial cognition, social function, and level of impulsive choice also remained undisturbed. Furthermore, these mice showed reduced dopamine transporter binding and slower dopamine clearance in vivo, suggesting that Vglut2-expressing cells in the STN regulate dopaminergic transmission. Our results demonstrate that altering the contribution of a limited population within the STN is sufficient to achieve results similar to STN lesions and high-frequency stimulation, but with fewer side effects.

Increased hippocampal excitability and impaired spatial memory function in mice lacking VGLUT2 selectively in neurons defined by tyrosine hydroxylase promoter activity

Three populations of neurons expressing the vesicular glutamate transporter 2 (Vglut2) were recently described in the A10 area of the mouse midbrain, of which two populations were shown to express the gene encoding, the rate-limiting enzyme for catecholamine synthesis, tyrosine hydroxylase (TH).One of these populations (‘‘TH– Vglut2 Class1’’) also expressed the dopamine transporter (DAT) gene while one did not ("TH–Vglut2 Class2"), and the remaining population did not express TH at all ("TH-Vglut2-only"). TH is known to be expressed by a promoter which shows two phases of activation, a transient one early during embryonal development, and a later one which gives rise to stable endogenous expression of the TH gene. The transient phase is, however, not specific to catecholaminergic neurons, a feature taken to advantage here as it enabled Vglut2 gene targeting within all three A10 populations expressing this gene, thus creating a new conditional knockout. These knockout mice showed impairment in spatial memory function. Electrophysiological analyses revealed a profound alteration of oscillatory activity in the CA3 region of the hippocampus. In addition to identifying a novel role for Vglut2 in hippocampus function, this study points to the need for improved genetic tools for targeting of the diversity of subpopulations of the A10 area

Ciclo de los negocios en Colombia: el papel de la política de estabilización

Este documento mide la sincronización entre las políticas de estabilización y el ciclo de los negocios en Colombia en el periodo comprendido entre marzo de 1990 y junio de 2013. Para la construcción de los ciclos se utiliza la metodología clásica y se construye un ciclo de referencia a partir de ciclos individuales de tres índices de actividad económica real. Con el fin de medir la sincronización entre el ciclo de nego­cios y los ciclos de las políticas fiscal y monetaria se utiliza el estadístico de Harding y Pagan (2006). Se concluye que durante el periodo de estudio las políticas de estabilización tienden a ser procíclicas (por el lado fiscal) y acíclicas (por el lado monetario). En la literatura se conoce a este fenómeno como when it rains, it pours y es común que se presente en economías emergentes como la colombiana

Perfil epidemiológico de la colelitiasis aguda en pacientes de 0 a 18 años en el Hospital Nacional de Niños Benjamín Bloom durante el período de Enero 2010 a Diciembre 2014

La Colelitiasis biliar se define como la presencia de material sólido, cálculos o lodo, en el tracto biliar, generalmente en la vesícula biliar. El concepto de enfermedad vesicular indica cambios funcionales y/o morfológicos (inflamación o fibrosis) en la vía biliar, secundarios al desarrollo de bilis con capacidad para formar cálculos o asociados a la litiasis vesicular. En el caso de nuestro estudio, definimos como cuadro agudo, el cuadro que se acompaña de dolor de inicio súbito, vómito, diarrea, y / o síntomas dispépticos, así como ictericia, que obligan a consultar de forma inmediata en un centro asistencial. El interés del pediatra por determinar la causa específica del dolor abdominal en niños, ha obligado a ampliar los conocimientos teóricos, a mejorar la sospecha clínica, a la identificación temprana de factores de riesgo, y la mejora en los manejos para la mayor supervivencia de niños con patología que predisponen a la colelitiasis biliar. Con el avance en las exploraciones ultrasonográficas, se ha descrito con mayor frecuencia casos de colelitiasis biliar en la edad pediátrica, con una incidencia mayor a la esperada hasta hace algunos años, para los diferentes grupos poblacionales.