66 research outputs found

    Desmedros y su incidencia en el estado de resultado Integral de las empresas comercializadoras de equipo de protección personal del distrito de San Miguel, año 2020

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    La investigación titulada “Desmedros y su incidencia en el Estado de Resultado Integral de las empresas comercializadoras de equipos de protección personal del distrito de San Miguel, año 2020”, tuvo como objetivo general explicar cómo los desmedros inciden en el Estado de Resultado Integral de las empresas comercializadoras de equipos de protección personal. La investigación realizada es aplicada ya que necesita de un análisis y solución al problema social. Diseño de estudio no experimental, porque no presenta manipulación en las variables, asimismo con un desarrollo de investigación transversal-descriptivo. Por otro lado la muestra está conformada por 34 personas del área contable, el instrumento fue aplicado a las empresas que conforman el estudio. La validez de instrumento fue mediante el juicio de expertos y respaldado por el uso del Alfa de Cronbach al medir la confiabilidad por último la comprobación de la hipótesis que se realizó con la prueba de Rho Spearman confirma la relación entre las variables. Por ello la investigación se llegó a la conclusión que los desmedros inciden en el Estado de Resultado Integral del distrito de San Miguel, año 2020

    TrkB signaling is required for postnatal survival of CNS neurons and protects hippocampal and motor neurons from axotomy-induced cell death

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    Newborn mice carrying targeted mutations in genes encoding neurotrophins or their signaling Trk receptors display severe neuronal deficits in the peripheral nervous system but not in the CNS. In this study, we show that trkB (¿/¿) mice have a significant increase in apoptotic cell death in different regions of the brain during early postnatal life. The most affected region in the brain is the dentate gyrus of the hippocampus, although elevated levels of pyknotic nuclei were also detected in cortical layers II and III and V and VI, the striatum, and the thalamus. Furthermore, axotomized hippocampal and motor neurons of trkB (¿/¿) mice have significantly lower survival rates than those of wild-type littermates. These results suggest that neurotrophin signaling through TrkB receptors plays a role in the survival of CNS neurons during postnatal development. Moreover, they indicate that TrkB receptor signaling protects subpopulations of CNS neurons from injury- and axotomy-induced cell death

    Taller de tributación y su incidencia en la cultura tributaria de los micro y pequeños empresarios del centro comercial Zona Franca, Trujillo - 2018

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    Esta investigación tiene como objetivo determinar la incidencia de un taller de tributación en la cultura tributaria de los micro y pequeños empresarios del centro comercial Zona Franca del distrito de Trujillo. Es una investigación de diseño pre experimental; se aplicó una encuesta (pretest – postest) para determinar el nivel de cultura tributaria de los comerciantes objeto de estudio. La población estuvo conformada por 250 micro y pequeños empresarios del centro comercial Zona Franca del distrito de Trujillo, y una muestra de 75 comerciantes que integran un grupo único. Para la colecta de información se ha utilizado como instrumento un cuestionario de 30 preguntas, cuya validez la determinó el juicio de expertos. Los resultados obtenidos del pretest indica que el 67% de los comerciantes se encuentran en un nivel bajo de cultura tributaria y el 9% se ubica en el nivel alto. Al grupo se le aplicó un taller de tributación organizado en seis sesiones. Los resultados obtenidos del postest reflejan que el 6% se ubica en el nivel bajo de cultura tributaria y el 75% de empresarios se ubican en el nivel alto. Por lo tanto, se concluye que la aplicación de un taller de tributación incide positivamente, mejorando en 66% respecto a los resultados iniciales, el nivel de cultura tributaria de los micro y pequeños empresarios del centro comercial Zona Franca.This research aimed to determine the influence of a Taxation Workshop in the tax culture of the micro and small entrepreneurs at the Centro Comercial Zona Franca in the district of Trujillo. It is a pre - experimental deign research. Data were collected by the application of a survey with a pretest and a posttest in order to determine the level of tax culture of the focus group. The population consists of 250 entrepreneurs from the Centro Comercial Zona Franca with a sample of 75 business people that form a single group. A questionnaire of 30 questions was applied as an instrument for collecting data and its validity was determined by expert judgment. The results from the pretest indicate that 67% of the traders has low level of taxation and just 9% of them has a high level of tax culture. The Taxation Workshop was organized and applied to this group in six sessions and the results obtained in the posttest show that just the 6% of participants has a low level of tax culture while 75% of entrepreneurs has a high level. Therefore, it concludes that the application of a Taxation Workshop has a positive impact, improving by 66% the tax culture level of the micro and small entrepreneurs at the Centro Comercial Zona Franca in the district of Trujillo.Tesi

    Cortistain is expressed in a distinct subset of cortical interneurons

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    Cortistatin is a presumptive neuropeptide that shares 11 of its 14 amino acids with somatostatin. In contrast to somatostatin, administration of cortistatin into the rat brain ventricles specifically enhances slow wave sleep, apparently by antagonizing the effects of acetylcholine on cortical excitability. Here we show that preprocortistatin mRNA is expressed in a subset of GABAergic cells in the cortex and hippocampus that partially overlap with those containing somatostatin. A significant percentage of cortistatin-positive neurons is also positive for parvalbumin. In contrast, no colocalization was found between cortistatin and calretinin, cholecystokinin, or vasoactive intestinal peptide. During development there is a transient increase in cortistatin-expressing cells in the second postnatal week in all cortical areas and in the dentate gyrus. A transient expression of preprocortistatin mRNA in the hilar region at P16 is paralleled by electrophysiological changes in dentate granule cells. Together, these observations suggest mechanisms by which cortistatin may regulate cortical activity

    Dyrk1A haploinsufficiency affects viability and causes developmental delay and abnormal brain morphology in mice

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    DYRK1A is the human orthologue of the Drosophila minibrain (mnb) gene, which is involved in postembryonic neurogenesis in flies. Because of its mapping position on chromosome 21 and the neurobehavioral alterations shown by mice overexpressing this gene, involvement of DYRK1A in some of the neurological defects of Down syndrome patients has been suggested. To gain insight into its physiological role, we have generated mice deficient in Dyrk1A function by gene targeting. Dyrk1A(−/−) null mutants presented a general growth delay and died during midgestation. Mice heterozygous for the mutation (Dyrk1A(+/−)) showed decreased neonatal viability and a significant body size reduction from birth to adulthood. General neurobehavioral analysis revealed preweaning developmental delay of Dyrk1A(+/−) mice and specific alterations in adults. Brains of Dyrk1A(+/−) mice were decreased in size in a region-specific manner, although the cytoarchitecture and neuronal components in most areas were not altered. Cell counts showed increased neuronal densities in some brain regions and a specific decrease in the number of neurons in the superior colliculus, which exhibited a significant size reduction. These data provide evidence about the nonredundant, vital role of Dyrk1A and suggest a conserved mode of action that determines normal growth and brain size in both mice and flies

    Unraveling Molecular Pathways Altered in MeCP2-Related Syndromes, in the Search for New Potential Avenues for Therapy

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    Methyl-CpG-binding protein 2 (MeCP2) is an X-linked epigenetic modulator whose dosage is critical for neural development and function. Loss-of-function mutations in MECP2 cause Rett Syndrome (RTT, OMIM #312750) while duplications in the Xq28 locus containing MECP2 and Interleukin-1 receptor-associated kinase 1 (IRAK1) cause MECP2 duplication syndrome (MDS, OMIM #300260). Both are rare neurodevelopmental disorders that share clinical symptoms, including intellectual disability, loss of speech, hand stereotypies, vasomotor deficits and seizures. The main objective of this exploratory study is to identify novel signaling pathways and potential quantitative biomarkers that could aid early diagnosis and/or the monitoring of disease progression in clinical trials. We analyzed by RT-PCR gene expression in whole blood and microRNA (miRNA) expression in plasma, in a cohort of 20 females with Rett syndrome, 2 males with MECP2 duplication syndrome and 28 healthy controls, and correlated RNA expression with disease and clinical parameters. We have identified a set of potential biomarker panels for RTT diagnostic and disease stratification of patients with microcephaly and vasomotor deficits. Our study sets the basis for larger studies leading to the identification of specific miRNA signatures for early RTT detection, stratification, disease progression and segregation from other neurodevelopmental disorders. Nevertheless, these data will require verification and validation in further studies with larger sample size including a whole range of ages

    Comprehensive analysis of GABAA-A1R developmental alterations in Rett Syndrome: setting the focus for therapeutic targets in the time frame of the disease

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    Rett syndrome, a serious neurodevelopmental disorder, has been associated with an altered expression of different synaptic-related proteins and aberrant glutamatergic and γ-aminobutyric acid (GABA)ergic neurotransmission. Despite its severity, it lacks a therapeutic option. Through this work we aimed to define the relationship between MeCP2 and GABAA.-A1 receptor expression, emphasizing the time dependence of such relationship. For this, we analyzed the expression of the ionotropic receptor subunit in different MeCP2 gene-dosage and developmental conditions, in cells lines, and in primary cultured neurons, as well as in different developmental stages of a Rett mouse model. Further, RNAseq and systems biology analysis was performed from post-mortem brain biopsies of Rett patients. We observed that the modulation of the MeCP2 expression in cellular models (both Neuro2a (N2A) cells and primary neuronal cultures) revealed a MeCP2 positive effect on the GABAA.-A1 receptor subunit expression, which did not occur in other proteins such as KCC2 (Potassium-chloride channel, member 5). In the Mecp2+/- mouse brain, both the KCC2 and GABA subunits expression were developmentally regulated, with a decreased expression during the pre-symptomatic stage, while the expression was variable in the adult symptomatic mice. Finally, the expression of the gamma-aminobutyric acid (GABA) receptor-related synaptic proteins from the postmortem brain biopsies of two Rett patients was evaluated, specifically revealing the GABA A1R subunit overexpression. The identification of the molecular changes along with the Rett syndrome prodromic stages strongly endorses the importance of time frame when addressing this disease, supporting the need for a neurotransmission-targeted early therapeutic intervention

    Learning and memory disabilities in IUGR babies: Functional and molecular analysis in a rat model

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    Introduction: Intrauterine growth restriction (IUGR) is the failure of the fetus to achieve its inherent growth potential, and it has frequently been associated with neurodevelopmental problems in childhood. Neurological disorders are mostly associated with IUGR babies with an abnormally high cephalization index (CI) and a brain sparing effect. However, a similar correlation has never been demonstrated in an animal model. The aim of this study was to determine the correlations between CI, functional deficits in learning and memory and alterations in synaptic proteins in a rat model of IUGR. Methods: Utero-placental insufficiency was induced by meso-ovarian vessel cauterization (CMO) in pregnant rats at embryonic day 17 (E17). Learning performance in an aquatic learning test was evaluated 25 days after birth and during 10 days. Some synaptic proteins were analyzed (PSD95, Synaptophysin) by Western blot and immunohistochemistry. Results: Placental insufficiency in CMO pups was associated with spatial memory deficits, which are correlated with a CI above the normal range. CMO pups presented altered levels of synaptic proteins PSD95 and synaptophysin in the hippocampus. Conclusions: The results of this study suggest that learning disabilities may be associated with altered development of excitatory neurotransmission and synaptic plasticity. Although interspecific differences in fetal response to placental insufficiency should be taken into account, the translation of these data to humans suggest that both IUGR babies and babies with a normal birth weight but with intrauterine Doppler alterations and abnormal CI should be closely followed to detect neurodevelopmental alterations during the postnatal periodEuropean Regional Development Fund BFU2014-55373-RMinisterio de Economía y Competitividad MAT2011-29778-C02-02Generalitat de Catalunya 2014 SGR 117

    Neuroprotection with Hypothermia and Allopurinol in an animal model of hypoxic-ischemic injury: Is it a gender question?

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    Abstract Background Hypoxic-ischemic encephalopathy (HIE) is one of the most important causes of neonatal brain injury. Therapeutic hypothermia (TH) is the standard treatment for term newborns after perinatal hypoxic ischemic injury (HI). Despite this, TH does not provide complete neuroprotection. Allopurinol seems to be a good neuroprotector in several animal studies, but it has never been tested in combination with hypothermia. Clinical findings show that male infants with (HI) fare more poorly than matched females in cognitive outcomes. However, there are few studies about neuroprotection taking gender into account in the results. The aim of the present study was to evaluate the potential additive neuroprotective effect of allopurinol when administrated in association with TH in a rodent model of moderate HI. Gender differences in neuroprotection were also evaluated Methods P10 male and female rat pups were subjected to HI (Vannucci model) and randomized into five groups: sham intervention (Control), no treatment (HI), hypothermia (HIH), allopurinol (HIA), and dual therapy (hypothermia and allopurinol) (HIHA). To evaluate a treatment's neuroprotective efficiency, 24 hours after the HI event caspase3 activation was measured. Damaged area and hippocampal volume were also measured 72 hours after the HI event. Negative geotaxis test was performed to evaluate early neurobehavioral reflexes. Learning and spatial memory were assessed via Morris Water Maze (MWM) test at 25 days of life. Results Damaged area and hippocampal volume were different among treatment groups (p = 0.001). The largest tissue lesion was observed in the HI group, followed by HIA. There were no differences between control, HIH, and HIHA. When learning process was analyzed, no differences were found. Females from the HIA group had similar results to the HIH and HIHA groups. Cleaved caspase 3 expression was increased in both HI and HIA. Despite this, in females cleaved caspase-3 was only differently increased in the HI group. All treated animals present an improvement in short-term (Negative geotaxis) and long-term (WMT) functional tests. Despite this, treated females present better long-term outcome. In short-term outcome no sex differences were observed. Conclusions Our results suggest that dual therapy confers great neuroprotection after an HI event. There were functional, histological, and molecular improvements in all treated groups. These differences were more important in females than in males. No statistically significant differences were found between HIHA and HIH; both of them present a great improvement. Our results support the idea of different regulation mechanisms and pathways of cell death, depending on gender

    Discovery of biomarker panels for neural dysfunction in inborn errors of amino acid metabolism.

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    Patients with inborn errors of amino acid metabolism frequently show neuropsychiatric symptoms despite accurate metabolic control. This study aimed to gain insight into the underlying mechanisms of neural dysfunction. Here we analyzed the expression of brain-derived neurotrophic factor (BDNF) and 10 genes required for correct brain functioning in plasma and blood of patients with Urea Cycle Disorders (UCD), Maple Syrup Urine Disease (MSUD) and controls. Receiver-operating characteristic (ROC) analysis was used to evaluate sensitivity and specificity of potential biomarkers. CACNA2D2 (α2δ2 subunit of voltage-gated calcium channels) and MECP2 (methyl-CpG binding protein 2) mRNA and protein showed an excellent neural function biomarker signature (AUC ≥ 0,925) for recognition of MSUD. THBS3 (thrombospondin 3) mRNA and AABA gave a very good biomarker signature (AUC 0,911) for executive-attention deficits. THBS3, LIN28A mRNA, and alanine showed a perfect biomarker signature (AUC 1) for behavioral and mood disorders. Finally, a panel of BDNF protein and at least two large neural AAs showed a perfect biomarker signature (AUC 1) for recognition of psychomotor delay, pointing to excessive protein restriction as central causative of psychomotor delay. To conclude, our study has identified promising biomarker panels for neural function evaluation, providing a base for future studies with larger samples
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