18 research outputs found

    Búsqueda y selección de una proteasa fúngica con potencial aplicación en la restauración de documentos históricos en el archivo de bogotá

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    Título en ingles: Screening for a fungal protease with potential in the biorestoration of historical valuable documents in Bogota Archive Resumen: Se ha buscado y seleccionado sistemáticamente una proteasa que pudiese ser usada en la eliminación “limpia” de encolantes sobre soportes documentales con valor de patrimonio histórico de forma eficiente y económica, a partir de la colección de hongos filamentosos del Archivo de Bogotá. De 74 morfotipos viables evaluados sobre placas selectivas, 32 morfotipos presentaron formación de halos de hidrólisis evidentes sobre placas diferenciales. De ellos, se evaluó el perfil isoenzimático de 8 morfotipos provenientes de muestreos documentales directos y de 2 morfotipos proteolíticos promisorios provenientes de un trabajo previo. Los 10 morfotipos seleccionados fueron representativos de los géneros Penicillium, Stachybotrys, Chaetomium, y Eladia. Luego de inducir la producción de proteasas extracelulares en medios líquidos diferenciales bajo tres fases de fermentación, se realizaron isoelectroénfoques analíticos tendientes a la observación de isoformas en el gradiente de pH establecido (3.0-10.0). Solo los morfotipos 8D (Chaetomium sp.) y 21D (Eladia saccula) presentaron una isoforma alcalina extrema, de puntos isoeléctricos 8.5 y 8.8, respectivamente, susceptible de selección con miras a su purificación y caracterización parcial de forma económica y eficiente. Los demás morfotipos, representativos de los géneros Penicillium sp., y Stachybotrys sp., presentaron unicamente isoformas proteolíticas en el rango acido de pH con puntos isoeléctricos que oscilan entre 4.0 y 5.0. Palabras clave: biodeterioro; hongo filamentoso; proteasa; halo de hidrólisis; punto isoeléctrico. Abstract: Studies on a protease as an efficient, environmental friendly and relatively economical remover of residual proteins for historical valuable documents were performed and was selected for this work, from the filamentous fungi collection of the Bogota Archive. 32 morphotypes of 74 evaluated show hydrolytic activities over differential solid media. From them, 8 morphotypes obtained directly from documental samples and representative of the genera Penicillium and Stachybotrys were selected and their isoenzyme profile were tested. Also 2 previous morphotypes with promisorius proteolytic activities and representative of the genera Chaetomium and Eladia were analysed. Extracelullar proteases production was induced in differential liquid media on three fermentation steps and analitycal isoelectrofocusing were performed over pH 3.0-10.0 ranges. Only the morphotypes 8D (Chaetomium sp.), and 21D (Eladia sp.), showed an alkaline isoform with pIs 8.5 and 8.8, respectly, suceptible of selection for its purification and characterization through efficient and economical way. The others morphotypes only showed acid isoforms with pIs in the range of 4.0 and 5.0. Key words: biodeterioration; filamentous fungi; protease; hydrolytic halo; isoelectric poin

    SARS-CoV-2 neutralizing antibodies : longevity, breadth, and evasion by emerging viral variants

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    The Severe Acute Respiratory Syndrome Coronavirus 2 (SAU ARS-CoV-2) antibody neutralization response and its evasion by emerging viral variants and variant of concern (VOC) are unknown, but critical to understand reinfection risk and breakthrough infection following vaccination. Antibody immunoreactivity against SARS-CoV-2 antigens and Spike variants, inhibition of Spike-driven virus–cell fusion, and infectious SARS-CoV-2 neutralization were characterized in 807 serial samples from 233 reverse transcription polymerase chain reaction (RT-PCR)–confirmed Coronavirus Disease 2019 (COVID-19) individuals with detailed demographics and followed up to 7 months. A broad and sustained polyantigenic immunoreactivity against SARS-CoV-2 Spike, Membrane, and Nucleocapsid proteins, along with high viral neutralization, was associated with COVID-19 severity. A subgroup of “high responders” maintained high neutralizing responses over time, representing ideal convalescent plasma donors. Antibodies generated against SARS-CoV-2 during the first COVID-19 wave had reduced immunoreactivity and neutralization potency to emerging Spike variants and VOC. Accurate monitoring of SARS-CoV-2 antibody responses would be essential for selection of optimal responders and vaccine monitoring and design

    All-Round Manipulation of the Actin Cytoskeleton by HIV

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    While significant progress has been made in terms of human immunodeficiency virus (HIV) therapy, treatment does not represent a cure and remains inaccessible to many people living with HIV. Continued mechanistic research into the viral life cycle and its intersection with many aspects of cellular biology are not only fundamental in the continued fight against HIV, but also provide many key observations of the workings of our immune system. Decades of HIV research have testified to the integral role of the actin cytoskeleton in both establishing and spreading the infection. Here, we review how the virus uses different strategies to manipulate cellular actin networks and increase the efficiency of various stages of its life cycle. While some HIV proteins seem able to bind to actin filaments directly, subversion of the cytoskeleton occurs indirectly by exploiting the power of actin regulatory proteins, which are corrupted at multiple levels. Furthermore, this manipulation is not restricted to a discrete class of proteins, but rather extends throughout all layers of the cytoskeleton. We discuss prominent examples of actin regulators that are exploited, neutralized or hijacked by the virus, and address how their coordinated deregulation can lead to changes in cellular behavior that promote viral spreading

    All-Round Manipulation of the Actin Cytoskeleton by HIV

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    While significant progress has been made in terms of human immunodeficiency virus (HIV) therapy, treatment does not represent a cure and remains inaccessible to many people living with HIV. Continued mechanistic research into the viral life cycle and its intersection with many aspects of cellular biology are not only fundamental in the continued fight against HIV, but also provide many key observations of the workings of our immune system. Decades of HIV research have testified to the integral role of the actin cytoskeleton in both establishing and spreading the infection. Here, we review how the virus uses different strategies to manipulate cellular actin networks and increase the efficiency of various stages of its life cycle. While some HIV proteins seem able to bind to actin filaments directly, subversion of the cytoskeleton occurs indirectly by exploiting the power of actin regulatory proteins, which are corrupted at multiple levels. Furthermore, this manipulation is not restricted to a discrete class of proteins, but rather extends throughout all layers of the cytoskeleton. We discuss prominent examples of actin regulators that are exploited, neutralized or hijacked by the virus, and address how their coordinated deregulation can lead to changes in cellular behavior that promote viral spreading

    Resolving the intersection of HIV and F-actin in the context of cell-cell viral spread

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    HIV has evolved elaborate mechanisms to manipulate the host cell’s actin cytoskeleton. This supports specific steps of the viral life cycle but also leads to cell-type specific changes in leukocyte shape and behaviour that promote overall spread of the infection. In particular, actin manipulation is important for direct cell-cell transfer of HIV (CCTH), which is now recognized as a highly efficient mode of viral spread.This study aimed to further resolve the molecular players and mechanisms involved in this process.Through the use of CRISPR–Cas9-mediated gene editing, herein we systematically interrogated the loss-of-function phenotype of over 50 cytoskeletal regulators, in both HIV-donor and target cells during CCTH. This was then combined with a portfolio of complementary assays ranging from live cell microscopy through to the ultrastructural resolution of focused ion beam scanning electron microscopy. This approach identified several core actin regulators to be required on both sides of viral transfer, including the Rho-GTPases Cdc42/Rac1 (signalling), upstream of the Arp2/3 complex (actin nucleator), and Profilin (which indirectly supports F-actin elongation, e.g. via Formins). In infected myeloid cells, Cdc42-Arp2/3 and Formins collaborated to form distinct “HIV-Filopodia”, which were shown to be important for CCTH. The overall findings of this work support that, while HIV uses diverse strategies to influence numerous cytoskeletal targets, there is a high tolerance for the individual loss of many manipulated regulators in the context of CCTH. However, core regulators that secure the cellular ability to mediate F-actin polymerization remain essential to this process, in particular via their contribution to cortical F-actin membrane protrusions that facilitate intercellular contacts and later maturation of the virological synapse. To conclude, we have mapped a landscape of complex interactions between HIV and the actin cytoskeleton. This not only builds on our understanding of F-actin regulation in cells of our immune system but will also facilitate the continued development of host-directed therapeutics for lentiviral and/or other pathogenic infections

    Búsqueda y selección de una proteasa fúngica con potencial aplicación en la restauración de documentos históricos en el Archivo de Bogotá

    No full text
    Studies on a protease as an efficient, environmental friendly and relatively economical remover of residual proteins for historical valuable documents were performed and was selected for this work, from the filamentous fungi collection of the Bogota Archive. 32 morphotypes of 74 evaluated show hydrolytic activities over differential solid media. From them, 8 morphotypes obtained directly from documental samples and representative of the genera Penicillium and Stachybotrys were selected and their isoenzyme profile were tested. Also 2 previous morphotypes with promisorius proteolytic activities and representative of the genera Chaetomium and Eladia were analysed. Extracelullar proteases production was induced in differential liquid media on three fermentation steps and analitycal isoelectrofocusing were performed over pH 3.0-10.0 ranges. Only the morphotypes 8D (Chaetomium sp.), and 21D (Eladia sp.), showed an alkaline isoform with pIs 8.5 and 8.8, respectly, suceptible of selection for its purification and characterization through efficient and economical way. The others morphotypes only showed acid isoforms with pIs in the range of 4.0 and 5.0.Se ha buscado y seleccionado sistemáticamente una proteasa que pudiese ser usada en la eliminación limpia de encolantes sobre soportes documentales con valor de patrimonio histórico de forma eficiente y económica, a partir de la colección de hongos filamentosos del Archivo de Bogotá. De 74 morfotipos viables evaluados sobre placas selectivas, 32 morfotipos presentaron formación de halos de hidrólisis evidentes sobre placas diferenciales. De ellos, se evaluó el perfil isoenzimático de 8 morfotipos provenientes de muestreos documentales directos y de 2 morfotipos proteolíticos promisorios provenientes de un trabajo previo. Los 10 morfotipos seleccionados fueron representativos de los géneros Penicillium, Stachybotrys, Chaetomium, y Eladia. Luego de inducir la producción de proteasas extracelulares en medios líquidos diferenciales bajo tres fases de fermentación, se realizaron isoelectroénfoques analíticos tendientes a la observación de isoformas en el gradiente de pH establecido (3.0-10.0). Solo los morfotipos 8D (Chaetomium sp.) y 21D (Eladia saccula) presentaron una isoforma alcalina extrema, de puntos isoeléctricos 8.5 y 8.8, respectivamente, susceptible de selección con miras a su purificación y caracterización parcial de forma económica y eficiente. Los demás morfotipos, representativos de los géneros Penicillium sp., y Stachybotrys sp., presentaron unicamente isoformas proteolíticas en el rango acido de pH con puntos isoeléctricos que oscilan entre 4.0 y 5.0

    Tiempo para quedar en embarazo e infertilidad entre mujeres ocupacionalmente expuestas a plaguicidas en empresas floricultoras de la sabana de Bogotá

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    IP 1101-04-10162ANEXOS: Time to first pregnancy among women working in agricultural production; Concepcion retrasada en una poblacion de mujeres horticultoras; Desarrollo y validacion deuna metodologia analitica para la determinacion de etilentiourea en orina y parches dermicos empleando cromatografia liquida de alta eficiencia; Analisis de sobrevida para determinar la asociacion entre expocicion aplaguicidas enempresas floricultoras y tiempo para quedar en embarazo; Exposicion a plaguicidas y aborto espontaneoen el primer embarazo en una poblacion colombiana; Reporte parcial de actividades de internado especialjunio 4 de 2001 a diciembre 2 de 2001; Time to firts pregnancy among women working in intensive agriculturalproduction in columbia.ARTICULO(S) EN REVISTA: Implementacion y validacion de unametodologia analitica para la determinacion de;etilenourea en orina y parches dermicos / Angela Viviana BarretoCharry, Ana Lucia Castiblanco Rodriguez,;Stella Ospina de Nigrinis, Alvaro Javier Idrovo. -- En: Revistacolombianade ciencias quimico farmaceuticas.; Vol. 32, no. 1 (2003); p. 1-5. -- PONENCIA(S) EN CONGRESO:Tiempo paralograr el primer embarazo entre;mujeres horticultoras colombianas / Alvaro J., Idrovo, LuzHelena Sanin, Donald Cole, Jorge Chavarro, Heidy;Caceres, Javier Narvaez, Mauricio Restrepo. -- En: Congreso deinvestigacion en salud publica (10 : 2003 mar.;5-7 : Cuernavaca Moleros, Mexico)

    Garantías judiciales de la Constitución. Volumen IV, Control de constitucionalidad en la Jurisdicción de lo Contencioso Administrativo

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    El grupo de investigación en Justicia Constitucional del Departamento de Derecho Constitucional de la Universidad Externado de Colombia se complace en publicar el libro Control de constitucionalidad en la Jurisdicción de lo Contencioso Administrativo. Este texto forma parte de la serie Garantías judiciales de la Constitución. Con esta serie, la Universidad busca contribuir al estudio y examen crítico del régimen procesal de los distintos mecanismos judiciales de protección de derechos fundamentales y de control de constitucionalidad previstos por el ordenamiento jurídico colombiano. En este libro encontrarán un estudio procesal exhaustivo sobre el control de constitucionalidad en la Jurisdicción de lo Contencioso Administrativo. En concreto, esta obra contiene cinco artículos que examinan los antecedentes de esta competencia en la Jurisdicción de lo Contencioso Administrativo, los mecanismos mediante los cuales se ejerce actualmente, los requisitos de la acción de nulidad por inconstitucionalidad, las normas que pueden ser controladas por este medio y el alcance de la decisión que toma el juez de lo contencioso administrativo. De esta manera, se da cuenta, en profundidad, de las principales cuestiones sustanciales y vicisitudes procesales del control de constitucionalidad en el marco de la Jurisdicción de lo Contencioso Administrativo.Primera edición

    LRRC15 suppresses SARS-CoV-2 infection and controls collagen production

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    The coronavirus pandemic has given everyone in society an education on the harms of spread of respiratory illness. Young healthy athletes are far less likely to suffer severe adverse consequences of viral illnesses than the elderly and frail, but they are not completely immune. Chronic fatigue (overtraining) is an uncommon outcome and myocarditis a rare one, but they both warrant due consideration. It is, therefore, a sensible individual strategy to 'stay home when sick' if only for these risks. Traditionally though, athletes have tended to push through (train and play when ill) because of competing concerns, such as key events/matches and 'not wanting to let teammates down'. Data from both low COVID-19 and high COVID-19 countries show that the number of cardiovascular deaths in a society correlates with the number of respiratory deaths at the same time, further linking respiratory viruses to cardiovascular deaths. We are now more aware of public health obligations to prevent the spread of respiratory illnesses, in particular to protect the more vulnerable members the community. This hopefully will correspond with a change in the culture of sport to one where it is considered 'the right thing to do', to 'stay home when sick'

    Patients with treated indolent lymphomas immunized with BNT162b2 have reduced anti‐spike neutralizing IgG to SARS‐CoV‐2 variants, but preserved antigen‐specific T cell responses

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    Patients with indolent lymphoma undertaking recurrent or continuous B cell suppression are at risk of severe COVID-19. Patients and healthy controls (HC; N=13) received 2 doses of BNT162b2: Follicular Lymphoma (FL; N=35) who were treatment naïve (TN; N=11) or received immunochemotherapy (ICT; N=23) and Waldenström's Macroglobulinemia (WM; N=37) including TN (N=9), ICT (N=14), or treated with Bruton's Tyrosine Kinase inhibitors (BTKi; N=12). Anti-spike IgG was determined by a high-sensitivity flow-cytometric assay, in addition to live-virus neutralization. Antigen-specific T cells were identified by co-expression of CD69/CD137 and CD25/CD134 on T cells. A subgroup (N=29) were assessed for third mRNA vaccine response, including omicron neutralization. One month after second BNT162b2, median anti-spike IgG mean fluorescence intensity (MFI) in FL ICT patients (9977) was 25-fold lower than TN (245898) and HC (228255, p=0.0002 for both). Anti-spike IgG correlated with lymphocyte count (r=0.63; p=0.002), and time from treatment, (r=0.56; p=0.007) on univariate analysis, but only with lymphocyte count on multivariate analysis (p=0.03). In the WM cohort, median anti-spike IgG MFI in BTKi patients (39039) was reduced compared to TN (220645, p=0.0008) and HC (p<0.0001). Anti-spike IgG correlated with neutralization of the delta variant (r=0.62, p<0.0001). Median neutralization titer for WM BTKi (0) was lower than HC (40, p<0.0001) for early-clade and delta. All cohorts had functional T cell responses. Median anti-spike IgG decreased 4-fold from second to third dose (p=0.004). Only 5/29 poor initial responders assessed after third vaccination demonstrated seroconversion and improvement in neutralization activity, including to the omicron variant. This article is protected by copyright. All rights reserved
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