1,850 research outputs found

    Estudio de determinación de la intensidad de Islas de Calor Urbana en la provincia de Lima

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    La isla de calor urbana (ICU) es caracterizada por un aumento de la temperatura del aire en el entorno urbano en comparación con las áreas circundantes menos urbanizadas o rurales (Oke, 2017; Zhang et al., 2019). Este fenómeno es generado por una combinación de factores, entre naturales, como los factores meteorológicos; y artificiales, como el diseño urbano (Rajagopalan et al., 2014; Keppas et al., 2021). En la provincia de Lima se han realizado estudios que identifican las ICU enfocándose en el área espacial que abarcaría este fenómeno (Menacho & Teruya, 2019; Soberón, 2014), también se ha identificado las medidas para aminorar su impacto (IDOM, 2021). No obstante, dichos estudios cuentan con una limitación en el espacio temporal, desconociéndose el comportamiento de las ICU en un periodo continúo de tiempo, incluso medido a escala horaria. De esta forma, se permite identificar las horas del día, meses y estaciones del año en que se darían las ICU más intensas y, a su vez, si su intensidad puede estar asociada a la influencia de otros parámetros meteorológicos o a otros eventos extremos como las olas de calor. Por ello, la presente investigación tuvo como objetivo general analizar las características de las ICU en la provincia de Lima durante el periodo 2018-2020. Para dicho fin, se utilizaron datos de seis (6) estaciones meteorológicas en el espacio urbano y 2 estaciones meteorológicas en el espacio rural en la provincia de Lima. A partir de estos datos se calcularon las ICU, a través de la diferencia de las temperaturas del aire entre una estación en el espacio urbano y otra estación en el espacio rural, metodología definida por Oke (1973) y adoptado por Founda (2015)

    Plan de responsabilidad social empresarial López Giraldo Ricardo Troquelados y Afines Industriales S.A.S.

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    Plan de responsabilidad social empresarial López Giraldo Ricardo Troquelados y Afines Industriales S.A.S.La Gerencia Estratégica aplicada con Responsabilidad Social Empresarial permite que las empresas generen además de un valor económico, un valor social. La RSE mejora los modelos productivos, la eficiencia y la sostenibilidad, basados en los valores de la igualdad, oportunidad, respeto y tolerancia, considerando que sus acciones afectan en su entorno. En este trabajo se escoge la empresa López Giraldo Ricardo – Troquelados y Afines Industriales, teniendo un perfil de “mipyme”, dentro del sector secundario o industrial de la economía analizando bajo un modelo gerencial de gestión, las fases necesarias en la construcción del Código de Ética y elaboración del plan de responsabilidad social empresarial. El Código de Ética es establecido con el fin de indicar el derrotero que la empresa seguirá en su actuar integral; en el Plan de RSE, se identifica el mapa de los Stakeholders donde se evidencian los grupos de interés involucrados en la actividad económica de la empresa, siendo estos actores influenciado res en las decisiones que la empresa tome. De igual forma, la propuesta del Plan de RSE define en sus tres dimensiones económicas, sociales y ambientales, los objetivos, estrategias e indicadores para seguimiento y generar soluciones reduciendo el impacto causado en su entorno. La RSE involucra una forma de pensar, actuar y ser en las empresas actualmente, pues a través del tiempo se han concientizado sobre los beneficios que se obtiene por su aplicación, considerando no solo los económicos, sino los sociales, humanos, ambientales aportándoles par su sostenibilidad

    Patients with Cholangiocarcinoma Present Specific RNA Profiles in Serum and Urine Extracellular Vesicles Mirroring the Tumor Expression: Novel Liquid Biopsy Biomarkers for Disease Diagnosis

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    Cholangiocarcinoma (CCA) comprises a group of heterogeneous biliary cancers with dismal prognosis. The etiologies of most CCAs are unknown, but primary sclerosing cholangitis (PSC) is a risk factor. Non-invasive diagnosis of CCA is challenging and accurate biomarkers are lacking. We aimed to characterize the transcriptomic profile of serum and urine extracellular vesicles (EVs) from patients with CCA, PSC, ulcerative colitis (UC), and healthy individuals. Serum and urine EVs were isolated by serial ultracentrifugations and characterized by nanoparticle tracking analysis, transmission electron microscopy, and immunoblotting. EVs transcriptome was determined by Illumina gene expression array [messenger RNAs (mRNA) and non-coding RNAs (ncRNAs)]. Differential RNA profiles were found in serum and urine EVs from patients with CCA compared to control groups (disease and healthy), showing high diagnostic capacity. The comparison of the mRNA profiles of serum or urine EVs from patients with CCA with the transcriptome of tumor tissues from two cohorts of patients, CCA cells in vitro, and CCA cellsderived EVs, identified 105 and 39 commonly-altered transcripts, respectively. Gene ontology analysis indicated that most commonly-altered mRNAs participate in carcinogenic steps. Overall, patients with CCA present specific RNA profiles in EVs mirroring the tumor, and constituting novel promising liquid biopsy biomarkers

    Causes of hOCT1-dependent cholangiocarcinoma resistance to sorafenib and sensitization by tumor-selective gene therapy

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    Although the multi-tyrosine kinase inhibitor sorafenib is useful in the treatment of several cancers, cholangiocarcinoma (CCA) is refractory to this drug. Among other mechanisms of chemoresistance, impaired uptake through human organic cation transporter type 1 (hOCT1) (gene SLC22A1) has been suggested. Here we have investigated the events accounting for this phenotypic characteristic and have evaluated the interest of selective gene therapy strategies to overcome this limitation. Gene expression and DNA methylation of SLC22A1 were analyzed using intrahepatic (iCCA) and extrahepatic (eCCA) biopsies (Copenhagen and Salamanca cohorts; n = 132) and The Cancer Genome Atlas (TCGA)-CHOL (n = 36). Decreased hOCT1 mRNA correlated with hypermethylation status of the SLC22A1 promoter. Treatment of CCA cells with decitabine (demethylating agent) or butyrate (histone deacetylase inhibitor) restored hOCT1 expression and increased sorafenib uptake. MicroRNAs able to induce hOCT1 mRNA decay were analyzed in paired samples of TCGA-CHOL (n = 9) and Copenhagen (n = 57) cohorts. Consistent up-regulation in tumor tissue was found for miR-141 and miR-330. High proportion of aberrant hOCT1 mRNA splicing in CCA was also seen. Lentiviral-mediated transduction of eCCA (EGI-1 and TFK-1) and iCCA (HuCCT1) cells with hOCT1 enhanced sorafenib uptake and cytotoxic effects. In chemically induced CCA in rats, reduced rOct1 expression was accompanied by impaired sorafenib uptake. In xenograft models of eCCA cells implanted in mouse liver, poor response to sorafenib was observed. However, tumor growth was markedly reduced by cotreatment with sorafenib and adenoviral vectors encoding hOCT1 under the control of the BIRC5 promoter, a gene highly up-regulated in CCA. Conclusion: The reason for impaired hOCT1-mediated sorafenib uptake by CCA is multifactorial. Gene therapy capable of selectively inducing hOCT1 in tumor cells can be considered a potentially useful chemosensitization strategy to improve the response of CCA to sorafenib

    Criteria for preclinical models of cholangiocarcinoma:scientific and medical relevance

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    Cholangiocarcinoma (CCA) is a rare malignancy that develops at any point along the biliary tree. CCA has a poor prognosis, its clinical management remains challenging, and effective treatments are lacking. Therefore, preclinical research is of pivotal importance and necessary to acquire a deeper understanding of CCA and improve therapeutic outcomes. Preclinical research involves developing and managing complementary experimental models, from in vitro assays using primary cells or cell lines cultured in 2D or 3D to in vivo models with engrafted material, chemically induced CCA or genetically engineered models. All are valuable tools with well-defined advantages and limitations. The choice of a preclinical model is guided by the question(s) to be addressed; ideally, results should be recapitulated in independent approaches. In this Consensus Statement, a task force of 45 experts in CCA molecular and cellular biology and clinicians, including pathologists, from ten countries provides recommendations on the minimal criteria for preclinical models to provide a uniform approach. These recommendations are based on two rounds of questionnaires completed by 35 (first round) and 45 (second round) experts to reach a consensus with 13 statements. An agreement was defined when at least 90% of the participants voting anonymously agreed with a statement. The ultimate goal was to transfer basic laboratory research to the clinics through increased disease understanding and to develop clinical biomarkers and innovative therapies for patients with CCA

    What to consider when pseudohypoparathyroidism is ruled out: IPPSD and differential diagnosis

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    Background: Pseudohypoparathyroidism (PHP) is a rare disease whose phenotypic features are rather difficult to identify in some cases. Thus, although these patients may present with the Albright''s hereditary osteodystrophy (AHO) phenotype, which is characterized by small stature, obesity with a rounded face, subcutaneous ossifications, mental retardation and brachydactyly, its manifestations are somewhat variable. Indeed, some of them present with a complete phenotype, whereas others show only subtle manifestations. In addition, the features of the AHO phenotype are not specific to it and a similar phenotype is also commonly observed in other syndromes. Brachydactyly type E (BDE) is the most specific and objective feature of the AHO phenotype, and several genes have been associated with syndromic BDE in the past few years. Moreover, these syndromes have a skeletal and endocrinological phenotype that overlaps with AHO/PHP. In light of the above, we have developed an algorithm to aid in genetic testing of patients with clinical features of AHO but with no causative molecular defect at the GNAS locus. Starting with the feature of brachydactyly, this algorithm allows the differential diagnosis to be broadened and, with the addition of other clinical features, can guide genetic testing. Methods: We reviewed our series of patients (n = 23) with a clinical diagnosis of AHO and with brachydactyly type E or similar pattern, who were negative for GNAS anomalies, and classify them according to the diagnosis algorithm to finally propose and analyse the most probable gene(s) in each case. Results: A review of the clinical data for our series of patients, and subsequent analysis of the candidate gene(s), allowed detection of the underlying molecular defect in 12 out of 23 patients: five patients harboured a mutation in PRKAR1A, one in PDE4D, four in TRPS1 and two in PTHLH. Conclusions: This study confirmed that the screening of other genes implicated in syndromes with BDE and AHO or a similar phenotype is very helpful for establishing a correct genetic diagnosis for those patients who have been misdiagnosed with "AHO-like phenotype" with an unknown genetic cause, and also for better describing the characteristic and differential features of these less common syndromes

    Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

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    A measurement of the cosmic-ray spectrum for energies exceeding 4×10184{\times}10^{18} eV is presented, which is based on the analysis of showers with zenith angles greater than 6060^{\circ} detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above 5.3×10185.3{\times}10^{18} eV, the "ankle", the flux can be described by a power law EγE^{-\gamma} with index γ=2.70±0.02(stat)±0.1(sys)\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)} followed by a smooth suppression region. For the energy (EsE_\text{s}) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find Es=(5.12±0.25(stat)1.2+1.0(sys))×1019E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19} eV.Comment: Replaced with published version. Added journal reference and DO
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