Pharmacological inhibition of mTORC1 reduces neural death and damage volume after MCAO by modulating microglial reactivity

Ischemic stroke is a sudden and acute disease characterized by neuronal death, increment of reactive gliosis (reactive microglia and astrocytes), and a severe inflammatory process. Neuroinflammation is an early event after cerebral ischemia, with microglia playing a leading role. Reactive microglia involve functional and morphological changes that drive a wide variety of phenotypes. In this context, deciphering the molecular mechanisms underlying such reactive microglial is essential to devise strategies to protect neurons and maintain certain brain functions affected by early neuroinflammation after ischemia. Here, we studied the role of mammalian target of rapamycin (mTOR) activity in the microglial response using a murine model of cerebral ischemia in the acute phase. We also determined the therapeutic relevance of the pharmacological administration of rapamycin, a mTOR inhibitor, before and after ischemic injury. Our data show that rapamycin, administered before or after brain ischemia induction, reduced the volume of brain damage and neuronal loss by attenuating the microglial response. Therefore, our findings indicate that the pharmacological inhibition of mTORC1 in the acute phase of ischemia may provide an alternative strategy to reduce neuronal damage through attenuation of the associated neuroinflammationThis work was supported by grants from the Spanish FEDER/Science and Innovation Ministry I\u2009+\u2009D\u2009+\u2009i-RETOS-PID2021-124801NB-I00, I\u2009+\u2009D\u2009+\u2009i-RETOS-PID2021-124801NB-I00, I\u2009+\u2009D\u2009+\u2009i-RETOS PID2020-115876GB-I00 and Centro de Investigaci\u00F3n Biom\u00E9dica en Red sobre Enfermedades Neurodegenerativas (CIBERNED; an initiative of the ISCIII) [PI2016/01]. Institutional grants from the Fundaci\u00F3n Ram\u00F3n Areces and Banco Santander to the CBMSO are also acknowledged by FW (CBMSO). M.V.G was supported by a EMBO short-term fellowship (8665). G.M.L was supported by a Tatiana P\u00E9rez de Guzm\u00E1n el Bueno fellowship 202

The structural assembly switch of cell division protein FtsZ probed with fluorescent allosteric inhibitors

FtsZ is a widely conserved tubulin-like GTPase that directs bacterial cell division and a new target for antibiotic discovery. This protein assembly machine cooperatively polymerizes forming single-stranded filaments, by means of self-switching between inactive and actively associating monomer conformations. The structural switch mechanism was proposed to involve a movement of the C-terminal and N-terminal FtsZ domains, opening a cleft between them, allosterically coupled to the formation of a tight association interface between consecutive subunits along the filament. The effective antibacterial benzamide PC190723 binds into the open interdomain cleft and stabilizes FtsZ filaments, thus impairing correct formation of the FtsZ ring for cell division. We have designed fluorescent analogs of PC190723 to probe the FtsZ structural assembly switch. Among them, nitrobenzoxadiazole probes specifically bind to assembled FtsZ rather than to monomers. Probes with several spacer lengths between the fluorophore and benzamide moieties suggest a binding site extension along the interdomain cleft. These probes label FtsZ rings of live Bacillus subtilis and Staphylococcus aureus, without apparently modifying normal cell morphology and growth, but at high concentrations they induce impaired bacterial division phenotypes typical of benzamide antibacterials. During the FtsZ assembly-disassembly process, the fluorescence anisotropy of the probes changes upon binding and dissociating from FtsZ, thus reporting open and closed FtsZ interdomain clefts. Our results demonstrate the structural mechanism of the FtsZ assembly switch, and suggest that the probes bind into the open clefts in cellular FtsZ polymers preferably to unassembled FtsZ in the bacterial cytosol

Synthetic inhibitors of bacterial cell division targeting the GTP-binding site of FtsZ

Cell division protein FtsZ is the organizer of the cytokinetic Z-ring in most bacteria and a target for new antibiotics. FtsZ assembles with GTP into filaments that hydrolyze the nucleotide at the association interface between monomers and then disassemble. We have replaced FtsZ's GTP with non-nucleotide synthetic inhibitors of bacterial division. We searched for these small molecules among compounds from the literature, from virtual screening (VS), and from our in-house synthetic library (UCM), employing a fluorescence anisotropy primary assay. From these screens we have identified the polyhydroxy aromatic compound UCM05 and its simplified analogue UCM44 that specifically bind to Bacillus subtilis FtsZ monomers with micromolar affinities and perturb normal assembly, as examined with light scattering, polymer sedimentation, and negative stain electron microscopy. On the other hand, these ligands induce the cooperative assembly of nucleotide-devoid archaeal FtsZ into distinct well-ordered polymers, different from GTP-induced filaments. These FtsZ inhibitors impair localization of FtsZ into the Z-ring and inhibit bacterial cell division. The chlorinated analogue UCM53 inhibits the growth of clinical isolates of antibiotic-resistant Staphylococcus aureus and Enterococcus faecalis. We suggest that these interfacial inhibitors recapitulate binding and some assembly-inducing effects of GTP but impair the correct structural dynamics of FtsZ filaments and thus inhibit bacterial division, possibly by binding to a small fraction of the FtsZ molecules in a bacterial cell, which opens a new approach to FtsZ-based antibacterial drug discovery.This work was supported by grants from Plan Nacional de Investigación BFU 2011-23416 (J.M.A.), BFU2099-09552 (P.C.), and SAF2010-22198 (M.L.L.-R.), grant CM S2010/BMD-2353 (M.L.L.-R, P.C., J.M.A.), and fellowships FPI (L.B.R.-A.), FPU (M.A.) and CSIC-JAE (E.R.-A.)

Targeting bacterial cell division protein FtsZ with small molecules and fluorescent probes

Trabajo presentado en el 248th National Meeting of the American-Chemical-Society (ACS), celebrado en San Francisco, CA (Estados Unidos), del 10 al 14 de agosto de 201

Associated factors for mortality in a COVID-19 colombian cohort : is the third wave relevant when Mu variant was predominant epidemiologically?

Q1Q1Pacientes con COVID-19Objectives: To evaluate the association between Colombia's third wave when the Mu variant was predominant epidemiologically (until 75%) in Colombia and COVID-19 all-cause in-hospital mortality. Methods: In this retrospective cohort, we included hospitalized patients ≥18 years with SARS-CoV-2 infection between March 2020 to September 2021 in ten hospitals from three cities in Colombia. Description analysis, survival, and multivariate Cox regression analyses were performed to evaluate the association between the third epidemic wave and in-hospital mortality. Results: A total of 25,371 patients were included. The age-stratified time-to-mortality curves showed differences according to epidemic waves in patients ≥75 years (log-rank test p = 0.012). In the multivariate Cox analysis, the third wave was not associated with increased mortality relative to the first wave (aHR 0.95; 95%CI 0.84–1.08), but there was an interaction between age ≥75 years and the third wave finding a lower HR for mortality (aHR 0.56, 95%CI 0.36–0.86). Conclusions: We did not find an increase in in-hospital mortality during the third epidemic wave in which the Mu variant was predominant in Colombia. The reduced hazard in mortality in patients ≥75 years hospitalized in the third wave could be explained by the high coverage of SARS-CoV-2 vaccination in this population and patients with underlying conditions.https://orcid.org/0000-0003-1833-1599https://orcid.org/0000-0001-5363-5729https://orcid.org/0000-0001-6964-2229https://orcid.org/0000-0003-3975-2835https://orcid.org/0000-0001-9441-4375Revista Internacional - IndexadaA1N

Caracterización fisicoquímica de la zona de transición acuático terrestre de un humedal tropical (Ayapel-Colombia)

Contextualization: The aquatic-terrestrial transition zone (ZTAT) in the floodplain (alluvial plain) Ramsar Ayapel (Colombia) remains flooded for more than half of the year, and its coastal strip generates a strong influence on the ecosystem. An approach to the spatial and temporal characterization of this zone is crucial for further functional analysis, especially when tropical floodplains are little explored except for some Amazonian ecosystems.  Knowledge gap: Floodplain dynamics are mainly regulated by flood pulses, directly influencing he physical and chemical conditions of water and sediment. Therefore, the biota is adapted to the flooding and waterlogging conditions of the ecosystem. However, research has addressed the terrestrial and aquatic phases as separate systems, making it necessary to resort to methodologies that demonstrate connectivity in the system and facilitate the interpretation of key factors in the ecological functioning of tropical wetlands.  Purpose: The research analyzed the structure and functioning of the ZTAT through physical and chemical variables at different times of the flood pulse.  Methodology: In two wetlands of the muddy complex, sensitive to the flood pulse, three samplings were carried out: rising water (July/2021), high water (September/2021), and declining water (March/2022). The ZTAT was monitored by delimiting it into four subzones: water, sediments, floodable soil, and soil. Results and conclusions: Significant changes in time associated with water level and nitrogen concentrations were revealed; while in space, assisted by the contrast of the ZTAT at the two sites, differences were reflected through in situ variables and soil characteristics. It was detected that depth, transparency, and a higher concentration of nitrogen forms, and some ions such as aluminum and magnesium generated differences on a time level. On the contrary, conductivity, calcium concentration, and variables associated with soil characteristics expressed it at the spatial level due to exploring the ZTAT. Therefore, the physicochemical dynamics of moments and sites in a wetland require a sampling design that, using the ZTAT, facilitates the scale of physicochemical analysis.Contextualización: la zona de transición acuático terrestre (ZTAT) en la planicie de inundación (llanura aluvial) Ramsar Ayapel (Colombia), permanece inundada más de la mitad de un año y su franja litoral genera una fuerte influencia en el ecosistema. Una aproximación a la caracterización espacial y temporal de esta zona es fundamental para un posterior análisis funcional, especialmente cuando, a excepción de algunos ecosistemas amazónicos, las planicies de inundación tropical son poco exploradas.  Vacío de conocimiento: la dinámica de las planicies de inundación está regulada principalmente por los pulsos de inundación, que influyen directamente en las condiciones físicas y químicas del agua y el sedimento; por lo anterior, la biota presenta adaptaciones a las condiciones de inundación y anegamiento del ecosistema. Sin embargo, las investigaciones han abordado la fase terrestre y acuática como sistemas separados, haciéndose necesario acudir a metodologías que evidencien la conectividad en el sistema y faciliten la interpretación de factores clave en el funcionamiento ecológico en los humedales tropicales.  Propósito: la investigación analizó la estructura y el funcionamiento de la ZTAT a través de variables físicas y químicas en diferentes momentos del pulso de inundación.  Metodología: en dos humedales del complejo cenagoso, sensibles al pulso de inundación, se realizaron tres muestreos: aguas en ascenso (julio de 2021); aguas altas (septiembre de 2021); y aguas en descenso (marzo de 2022). Se monitoreó la ZTAT delimitándola en cuatro subzonas: agua, sedimentos, suelo inundable y suelo.  Resultados y conclusiones: se revelaron cambios significativos en el tiempo asociados al nivel del agua y a las concentraciones de nitrógeno; mientras en el espacio, asistido por el contraste de la ZTAT en los dos sitios, se reflejaron diferenciaciones a través de las variables in situ y las características del suelo. Se detectó que la profundidad, transparencia y una mayor concentración de formas de nitrógeno y algunos iones como aluminio y magnesio generaron diferencias a nivel temporal; mientras la conductividad, concentración del calcio y variables asociadas a las características del suelo lo expresaron a nivel espacial gracias a la exploración de la ZTAT; por tanto, la dinámica fisicoquímica de momentos y sitios en un humedal requiere un diseño de muestreo que por medio de la ZTAT facilita la escala de análisis fisicoquímico

Newer generations of multi-target CAR and STAb-T immunotherapeutics: NEXT CART Consortium as a cooperative effort to overcome current limitations

Adoptive T cellular immunotherapies have emerged as relevant approaches for treating cancer patients who have relapsed or become refractory (R/R) to traditional cancer treatments. Chimeric antigen receptor (CAR) T-cell therapy has improved survival in various hematological malignancies. However, significant limitations still impede the widespread adoption of these therapies in most cancers. To advance in this field, six research groups have created the “NEXT Generation CART MAD Consortium” (NEXT CART) in Madrid’s Community, which aims to develop novel cell-based immunotherapies for R/R and poor prognosis cancers. At NEXT CART, various basic and translational research groups and hospitals in Madrid concur to share and synergize their basic expertise in immunotherapy, gene therapy, and immunological synapse, and clinical expertise in pediatric and adult oncology. NEXT CART goal is to develop new cell engineering approaches and treatments for R/R adult and pediatric neoplasms to evaluate in multicenter clinical trials. Here, we discuss the current limitations of T cell-based therapies and introduce our perspective on future developments. Advancement opportunities include developing allogeneic products, optimizing CAR signaling domains, combining cellular immunotherapies, multi-targeting strategies, and improving tumor-infiltrating lymphocytes (TILs)/T cell receptor (TCR) therapy. Furthermore, basic studies aim to identify novel tumor targets, tumor molecules in the tumor microenvironment that impact CAR efficacy, and strategies to enhance the efficiency of the immunological synapse between immune and tumor cells. Our perspective of current cellular immunotherapy underscores the potential of these treatments while acknowledging the existing hurdles that demand innovative solutions to develop their potential for cancer treatment fully

Memorias de investigación: Feria de Semilleros y Jornadas de Investigación de uniminuto, Seccional Antioquia - Chocó.

Feria de Semilleros y Jornadas de Investigación de uniminuto, Seccional Antioquia - Chocó.Esta publicación busca divulgar investigaciones y producción académica en diferentes disciplinas, realizadas por estudiantes y docentes de UNIMINUTO Seccional Antioquia – Chocó, así como dar a conocer los semilleros de investigación que participaron en la V Feria de Semilleros, con el fin de visibilizar el trabajo que realiza el Centro de Investigación para el Desarrollo de UNIMINUTO Bello —CIDUB—, con respecto a debates académicos y espacios de interlocución. Igualmente, permite que la comunidad educativa conozca los temas de investigación y las discusiones que se están dando entre los semilleros y grupos de investigación, para así buscar puntos de encuentro y sinergias entre los investigadores. Adicionalmente, el texto se convierte en una invitación para que se vinculen otros investigadores, docentes, estudiantes e incluso otras instituciones a los procesos investigativos coordinados desde el CIDUB

Memorias de investigación: Feria de Semilleros y Jornadas de Investigación de uniminuto, Seccional Antioquia - Chocó.

Feria de Semilleros y Jornadas de Investigación de uniminuto, Seccional Antioquia - Chocó.Esta publicación busca divulgar investigaciones y producción académica en diferentes disciplinas, realizadas por estudiantes y docentes de UNIMINUTO Seccional Antioquia – Chocó, así como dar a conocer los semilleros de investigación que participaron en la V Feria de Semilleros, con el fin de visibilizar el trabajo que realiza el Centro de Investigación para el Desarrollo de UNIMINUTO Bello —CIDUB—, con respecto a debates académicos y espacios de interlocución. Igualmente, permite que la comunidad educativa conozca los temas de investigación y las discusiones que se están dando entre los semilleros y grupos de investigación, para así buscar puntos de encuentro y sinergias entre los investigadores. Adicionalmente, el texto se convierte en una invitación para que se vinculen otros investigadores, docentes, estudiantes e incluso otras instituciones a los procesos investigativos coordinados desde el CIDUB