1,426 research outputs found
IMPACTO DE LOS PROCESOS DE EVALUACIÓN Y ACREDITACIÓN EN EL ÁMBITO UNIVERSITARIO
La educación superior debe introducir la evaluación institucional en su quehacer habitual, ya sea mediante procesos de autorregulación, mediante evaluaciones externas o ambos. Durante los procesos de evaluación y acreditación, los miembros de la comunidad universitaria se tornan más sensibles de todo cuanto sucede en su entorno. Esto puede convertirse en una oportunidad que debe ser aprovechada por los responsables de la conducción para lograr cambios de hábitos positivos dentro de la comunidad, generar conductas que permitan mejorar tanto el aspecto académico como institucional y corregir aquellos aspectos que resulten perjudiciales para el buen funcionamiento institucional. Como miembros de la comunidad universitaria, masa crítica pensante y autónoma, tenemos la obligación de estar siempre alertos, investigar y debatir las causas y los efectos de las políticas que afectan a nuestra Institución. En este trabajo analizaremos los impactos más destacables de los procesos de evaluación y de acreditación sobre el cuerpo académico y sobre la institución universitaria. Se presenta también el resultado de un estudio cualitativo basado en entrevistas a docentes de la FRT-UTN, respecto a estos temas trascendentales
Hippocampal Memory Recovery After Acute Stress: A Behavioral, Morphological and Molecular Study
Indexación: Scopus.Laboratory of Neuroplasticity and Neurogenetics, Department of Biochemistry and Molecular Biology, Faculty of Chemistry and Pharmaceutical Sciences, Universidad de Chile, Santiago, Chile, 2Laboratorio Farmacología del Comportamiento, ICBM, Facultad de Medicina, Universidad de Chile, Santiago, Chile, 3Department of Kinesiology, Faculty of Health Sciences, Universidad Católica del Maule, Talca, Chile, 4Facultad de Psicología, Universidad de Talca, Talca, Chile, 5Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile, 6Escuela de Química y Farmacia, Facultad de Medicina, Universidad Andres Bello, Santiago, Chile.This study was supported by the following grants: Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT) 1120528 (JLF), Fondo Central de Investigación, Universidad de Chile ENL025/16 (JLF).Several studies have shown that a single exposure to stress may improve or impair learning and memory processes, depending on the timing in which the stress event occurs with relation to the acquisition phase. However, to date there is no information about the molecular changes that occur at the synapse during the stress-induced memory modification and after a recovery period. In particular, there are no studies that have evaluated—at the same time—the temporality of stress and stress recovery period in hippocampal short-term memory and the effects on dendritic spine morphology, along with variations in N-methyl-D-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunits. The aim of our study was to take a multidimensional approach to investigate concomitant behavioral, morphological and molecular changes induced by a single restraint stress exposure (2.5 h) and a recovery period of 6 and 24 h in rats. We found that acute stress elicited a reduced preference to explore an object placed in a novel position (a hippocampal-dependent task). These changes were accompanied by increased activity of LIM kinase I (LIMK; an actin-remodeling protein) and increased levels of NR2A subunits of NMDA receptors. After 6 h of recovery from stress, rats showed similar preference to explore an object placed in a novel or familiar position, but density of immature spines increased in secondary CA1 apical dendrites, along with a transient rise in GluA2 AMPA receptor subunits. After 24 h of recovery from stress, the animals showed a preference to explore an object placed in a novel position, which was accompanied by a normalization of NMDA and AMPA receptor subunits to control values. Our data suggest that acute stress produces reversible molecular and behavioral changes 24 h after stress, allowing a full reestablishment of hippocampal-related memory. Further studies need to be conducted to deepen our understanding of these changes and their reciprocal interactions.Adaptive stress responses are a promising avenue to develop interventions aiming at restoring hippocampal function impaired by repetitive stress exposure. © 2018 Aguayo, Tejos-Bravo, Díaz-Véliz, Pacheco, García-Rojo, Corrales, Olave, Aliaga, Ulloa, Avalos, Román-Albasini, Rojas and Fiedler.https://www.frontiersin.org/articles/10.3389/fnmol.2018.00283/ful
The Nod-Like Receptor (NLR) Family: A Tale of Similarities and Differences
Innate immunity represents an important system with a variety of vital processes at the core of many diseases. In recent years, the central role of the Nod-like receptor (NLR) protein family became increasingly appreciated in innate immune responses. NLRs are classified as part of the signal transduction ATPases with numerous domains (STAND) clade within the AAA+ ATPase family. They typically feature an N-terminal effector domain, a central nucleotide-binding domain (NACHT) and a C-terminal ligand-binding region that is composed of several leucine-rich repeats (LRRs). NLRs are believed to initiate or regulate host defense pathways through formation of signaling platforms that subsequently trigger the activation of inflammatory caspases and NF-kB. Despite their fundamental role in orchestrating key pathways in innate immunity, their mode of action in molecular terms remains largely unknown. Here we present the first comprehensive sequence and structure modeling analysis of NLR proteins, revealing that NLRs posses a domain architecture similar to the apoptotic initiator protein Apaf-1. Apaf-1 performs its cellular function by the formation of a heptameric platform, dubbed apoptosome, ultimately triggering the controlled demise of the affected cell. The mechanism of apoptosome formation by Apaf-1 potentially offers insight into the activation mechanisms of NLR proteins. Multiple sequence alignment analysis and homology modeling revealed Apaf-1-like structural features in most members of the NLR family, suggesting a similar biochemical behaviour in catalytic activity and oligomerization. Evolutionary tree comparisons substantiate the conservation of characteristic functional regions within the NLR family and are in good agreement with domain distributions found in distinct NLRs. Importantly, the analysis of LRR domains reveals surprisingly low conservation levels among putative ligand-binding motifs. The same is true for the effector domains exhibiting distinct interfaces ensuring specific interactions with downstream target proteins. All together these factors suggest specific biological functions for individual NLRs
Overdiagnosis of Intestinal Amoebiasis Associated to Serial Microscopical Examination of Faeces:Some Precisions on a Problem
Characterization of the protease domain of Rice tungro bacilliform virus responsible for the processing of the capsid protein from the polyprotein
BACKGROUND: Rice tungro bacilliform virus (RTBV) is a pararetrovirus, and a member of the family Caulimoviridae in the genus Badnavirus. RTBV has a long open reading frame that encodes a large polyprotein (P3). Pararetroviruses show similarities with retroviruses in molecular organization and replication. P3 contains a putative movement protein (MP), the capsid protein (CP), the aspartate protease (PR) and the reverse transcriptase (RT) with a ribonuclease H activity. PR is a member of the cluster of retroviral proteases and serves to proteolytically process P3. Previous work established the N- and C-terminal amino acid sequences of CP and RT, processing of RT by PR, and estimated the molecular mass of PR by western blot assays. RESULTS: A molecular mass of a protein that was associated with virions was determined by in-line HPLC electrospray ionization mass spectral analysis. Comparison with retroviral proteases amino acid sequences allowed the characterization of a putative protease domain in this protein. Structural modelling revealed strong resemblance with retroviral proteases, with overall folds surrounding the active site being well conserved. Expression in E. coli of putative domain was affected by the presence or absence of the active site in the construct. Analysis of processing of CP by PR, using pulse chase labelling experiments, demonstrated that the 37 kDa capsid protein was dependent on the presence of the protease in the constructs. CONCLUSION: The findings suggest the characterization of the RTBV protease domain. Sequence analysis, structural modelling, in vitro expression studies are evidence to consider the putative domain as being the protease domain. Analysis of expression of different peptides corresponding to various domains of P3 suggests a processing of CP by PR. This work clarifies the organization of the RTBV polyprotein, and its processing by the RTBV protease
SPOC: A widely distributed domain associated with cancer, apoptosis and transcription
BACKGROUND: The Split ends (Spen) family are large proteins characterised by N-terminal RNA recognition motifs (RRMs) and a conserved SPOC (Spen paralog and ortholog C-terminal) domain. The aim of this study is to characterize the family at the sequence level. RESULTS: We describe undetected members of the Spen family in other lineages (Plasmodium and Plants) and localise SPOC in a new domain context, in a family that is common to all eukaryotes using profile-based sequence searches and structural prediction methods. CONCLUSIONS: The widely distributed DIO (Death inducer-obliterator) family is related to cancer and apoptosis and offers new clues about SPOC domain functionality
Variables that influence HIV-1 cerebrospinal fluid viral load in cryptococcal meningitis: a linear regression analysis
Phase II study of the safety and efficacy of the anti-PD-1 antibody balstilimab in patients with recurrent and/or metastatic cervical cancer
Cervical cancer; Checkpoint inhibitor; ImmunotherapyCáncer de cuello uterino; Inhibidor de puntos de control; InmunoterapiaCàncer cervical; Inhibidor de punts de control; ImmunoteràpiaObjective
This phase II clinical trial evaluated the safety and antitumor activity of balstilimab, an anti-PD-1 antibody, in patients with previously-treated, recurrent/metastatic cervical cancer.
Methods
Eligible patients were 18 years or older with recurrent and/or metastatic cervical cancer and who had relapsed after a prior platinum-based treatment regimen for advanced disease. Balstilimab was administered intravenously at 3 mg/kg once every two weeks, for up to 24 months. The primary endpoint was objective response rate (ORR, RECIST v1.1) as assessed by an independent review committee.
Results
At data cutoff, 161 women (median age, 53 years [range 25–81]) were enrolled and treated with balstilimab. Of these, 140 had measurable disease at baseline and one prior line of platinum-based therapy in the metastatic, persistent, or recurrent setting; these patients were included in the efficacy analyses. The ORR was 15% (95% CI, 10.0%–21.8%) and included 5 patients with a complete response and 16 with a partial response. The median duration of response was 15.4 months. In patients with PD-L1-positive tumors the ORR was 20%, however patients with PD-L1-negative tumors also responded to balstilimab (ORR, 7.9%). Responses were not restricted to tumors of squamous cell histology, and an ORR of 12.5% was seen in the subset of patients with cervical adenocarcinoma. The disease control rate was 49.3% (95% CI, 41.1%–57.5%). Immune-mediated enterocolitis (3.1%) and diarrhea (1.9%) were the most common grade 3 or higher treatment-related adverse events.
Conclusion
Balstilimab demonstrated meaningful and durable clinical activity, with manageable safety, in patients with previously-treated, recurrent/metastatic cervical cancer.This study was funded by Agenus Inc
T cells loaded with magnetic nanoparticles are retained in peripheral lymph nodes by the application of a magnetic field
T lymphocytes are highly dynamic elements of the immune system with a tightly regulated migration. T cell-based transfer therapies are promising therapeutic approaches which in vivo efficacy is often limited by the small proportion of administered cells that reaches the region of interest. Manipulating T cell localisation to improve specific targeting will increase the effectiveness of these therapies. Nanotechnology has been successfully used for localized release of drugs and biomolecules. In particular, magnetic nanoparticles (MNPs) loaded with biomolecules can be specifically targeted to a location by an external magnetic field (EMF). The present work studies whether MNP-loaded T cells could be targeted and retained in vitro and in vivo at a site of interest with an EMF.Results: T cells were unable to internalize the different MNPs used in this study, which remained in close association with the cell membrane. T cells loaded with an appropriate MNP concentration were attracted to an EMF and retained in an in vitro capillary flow-system. MNP-loaded T cells were also magnetically retained in the lymph nodes after adoptive transfer in in vivo models. This enhanced in vivo retention was in part due to the EMF application and to a reduced circulating cell speed within the organ. This combined use of MNPs and EMFs did not alter T cell viability or function.Conclusions: These studies reveal a promising approach to favour cell retention that could be implemented to improve cell- based therapy
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