617 research outputs found

    LEARNING AND TECHNOLOGY: AN EXPERIMENT

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    Regulatory polymorphisms in extracellular matrix protease genes and susceptibility to rheumatoid arthritis: a case-control study

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    Many extracellular matrix (ECM) proteases seem to be important in rheumatoid arthritis (RA) and regulation of their transcription levels is a critical mechanism for controlling their activity. We have investigated, therefore, whether the best-characterized single nucleotide polymorphisms (SNPs) affecting transcription of the ECM proteases that have been related with joint pathology are associated with RA susceptibility. Nine SNPs in eight genes were selected by bibliographic search, including SNPs in the genes encoding matrix metalloproteinase (MMP)1, MMP2, MMP3, MMP7, MMP9, MMP13, plasminogen activator, tissue type (PLAT) and PAI-1. They were studied in a case-control setting that included 550 RA patients and 652 controls of Spanish ancestry from a single center. Genotyping was performed by single-base extension. Only two of the nine SNPs showed significant association with RA susceptibility. RA patients showed increased frequencies of the -7351 T allele of the gene encoding PLAT (36.4% versus 32.1% in controls, p = 0.026) and the -1306 T allele of the gene encoding MMP2 (24.5% versus 20.3% in controls, p = 0.013). These two alleles seemed to cooperate according to an additive model with respect to increased RA susceptibility (p = 0.004), and they were the low-expression alleles of the respective SNPs in a PLAT enhancer and the MMP2 promoter. These findings are in agreement with previous data suggesting that these two ECM proteases have a protective role in RA pathology. Confirmation of these associations will be needed to support these hypotheses. The remaining SNPs did not show association, either individually or collectively. Therefore, although regulatory SNPs in ECM proteases did not show any major effect on RA susceptibility, it was possible to find modest associations that, if replicated, will have interesting implications in the understanding of RA pathology

    Lack of association of a variable number of aspartic acid residues in the asporin gene with osteoarthritis susceptibility: case-control studies in Spanish Caucasians

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    A recent genetic association study has identified a microsatellite in the coding sequence of the asporin gene as a susceptibility factor for osteoarthritis (OA). Alleles of this microsatellite determine the variable number of aspartic acid residues in the amino-terminal end of the asporin protein. Asporin binds directly to the growth factor transforming growth factor beta and inhibits its anabolic effects in cartilage, which include stimulation of collagen and aggrecan synthesis. The OA-associated allele, with 14 aspartic acid residues, inhibits the anabolic effects of transforming growth factor beta more strongly than other asporin alleles, leading to increased OA liability. We have explored whether the association found in several cohorts of Japanese hip OA and knee OA patients was also present in Spanish Caucasians. We studied patients that had undergone total joint replacement for primary OA in the hip (n = 303) or the knee (n = 188) and patients with hand OA (n = 233), and we compared their results with controls (n = 294) lacking overt OA clinical symptoms. No significant differences were observed in any of the multiple comparisons performed, which included global tests of allele frequency distributions and specific comparisons as well as stratification by affected joint and by sex. Our results, together with reports from the United Kingdom and Greece, indicate that the stretch of aspartic acid residues in asporin is not an important factor in OA susceptibility among European Caucasians. It remains possible that lifestyle, environmental or genetic differences allow for an important effect of asporin variants in other ethnic groups as has been reported in the Japanese, but this should be supported by additional studies

    La acupuntura urbana en el espacio público del Asentamiento Humano San Juan de la ciudad de Yurimaguas, 2023

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    Sin duda la problemática del espacio público abandonado y obsoleto en asentamientos humanos informales requiere de imperativas soluciones. En la actualidad los asentamientos humanos informales son una problemática constante, según el informe de Habitad III (2016) alrededor de un cuarto de toda la población urbana está establecida dentro de algún asentamiento informal, especialmente en “barrios marginales”, padeciendo mayor exclusión económica y social en comparación con los beneficios y oportunidades de sectores ya urbanizados. En el Perú existe la “Ley de gestión y protección de los espacios públicos” (Ley N° 31199) donde se decreta que el Estado tiene que facilitar la creación y conservación de espacios públicos que promuevan el desarrollo del valor ambiental, cultural y recreacional en los ciudadanos, sin embargo, los espacios públicos no llegan a ser de calidad en todos los sectores de la población peruana. Al entender la relevancia del espacio público abandonados en asentamientos informales y como la acupuntura urbana los regeneraría, como problema de la investigación se plantea investigar en qué medida la acupuntura urbana mejora el espacio público de los asentamientos humanos en Yurimaguas, de tal manera el objetivo principal del trabajo es de definir la acupuntura urbana como estrategia de regeneración de los espacios públicos en el asentamiento humano San Juan de la ciudad de Yurimaguas.Sin duda la problemática del espacio público abandonado y obsoleto en asentamientos humanos informales requiere de imperativas soluciones. En la actualidad los asentamientos humanos informales son una problemática constante, según el informe de Habitad III (2016) alrededor de un cuarto de toda la población urbana está establecida dentro de algún asentamiento informal, especialmente en “barrios marginales”, padeciendo mayor exclusión económica y social en comparación con los beneficios y oportunidades de sectores ya urbanizados. En el Perú existe la “Ley de gestión y protección de los espacios públicos” (Ley N° 31199) donde se decreta que el Estado tiene que facilitar la creación y conservación de espacios públicos que promuevan el desarrollo del valor ambiental, cultural y recreacional en los ciudadanos, sin embargo, los espacios públicos no llegan a ser de calidad en todos los sectores de la población peruana. Al entender la relevancia del espacio público abandonados en asentamientos informales y como la acupuntura urbana los regeneraría, como problema de la investigación se plantea investigar en qué medida la acupuntura urbana mejora el espacio público de los asentamientos humanos en Yurimaguas, de tal manera el objetivo principal del trabajo es de definir la acupuntura urbana como estrategia de regeneración de los espacios públicos en el asentamiento humano San Juan de la ciudad de Yurimaguas

    Citoquinas y recuento de Linfocitos T en pacientes en fase aguda y crónica de infección por Bartonella bacilliformis, en una área endémica del Perú: estudio piloto

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    Human Bartonellosis has an acute phase characterized by fever and hemolytic anemia, and a chronic phase with bacillary angiomatosis-like lesions. This cross-sectional pilot study evaluated the immunology patterns using pre- and post-treatment samples in patients with Human Bartonellosis. Patients between five and 60 years of age, from endemic areas in Peru, in the acute or chronic phases were included. In patients in the acute phase of Bartonellosis a state of immune peripheral tolerance should be established for persistence of the infection. Our findings were that elevation of the anti-inflammatory cytokine IL-10 and numeric abnormalities of CD4+ and CD8+ T-Lymphocyte counts correlated significantly with an unfavorable immune state. During the chronic phase, the elevated levels of IFN-γ and IL-4 observed in our series correlated with previous findings of endothelial invasion of B. henselae in animal models.La Bartonelosis Humana, tiene una fase aguda caracterizada por fiebre y anemia hemolítica, así como una fase crónica con lesiones semejantes a angiomatosis bacilar. En un estudio transversal piloto los patrones inmunológicos en pacientes con Bartonelosis Humana fueron estudiados mediante muestras pre y post tratamiento. Pacientes entre 5 y 60 años en fase aguda y crónica fueron incluidos en área endémica del Perú. En aquellos pacientes con fase aguda, una fase de tolerancia inmunológica periférica es necesaria para la persistencia de la infección. Los hallazgos de significativa elevación de citoquina anti-inflamatoria (IL-10) y anormalidades numéricas en el recuentos de Linfocitos T CD4+ y CD8+ correlacionan con un estado inmune que favorece la infección. Durante la fase crónica, elevados niveles de INF-γ y IL-4 observados en la serie de pacientes correlacionan con previos hallazgos en modelos animales que favorecen la invasión del endotelio por B. henselae

    ANÃLISIS FODA Y PERSPECTIVAS DEL CULTIVO DEL NOGAL PECANERO EN CHIHUAHUA

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    Pecan production is one of the most important crops in our country. It not only has an economical capacity as a generator of foreign currency, but also for the social context in which it develops its production. Most of the pecan growers have small sized orchards, but at the same time, there are few pecan growers with large sized orchards that use modern technology. The objective of this study is to present a SWOT analysis of the pecan system and to describe the contexts in which it is produced and commercialized, as well as the main characteristics and problems that appear in pecan production, as well as the prediction of its future under current production and management conditions.WOTS-UP analysis, pecan system, production and commercialization., Agribusiness,

    RENTABILIDAD DEL NOGAL PECANERO BAJO SISTEMAS DE PRODUCCIÓN DE MEDIANA TECNOLOGÃA EN DELICIAS, CHIHUAHUA

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    Pecans (Carya Illinoinensis [Wangenh] K. Koch) are a native food of North America and represent a high economic crop value in the north of Mexico, mainly in the state of Chihuahua, the biggest pecan nut producer in this country. The goal of this study was to evaluate the profitability of pecan orchards in the municipality of Delicias, Chihuahua. Some microeconomic and market information from 2008 were collected from pecan growers and specialists through the technique of Experts' Panel. Standard financial analysis and a Monte Carlo simulation model were used to evaluate the probabilities of risk for net cash income (NCI) and return on capital employed (RCE). The NCI obtained was $277,000 and RC 111.7%, indicating that pecan orchards show high profitability when is produced under medium-technology conditions in the municipality of Delicias, Chihuahua.Carya Illinoinensis, production costs, Monte Carlo simulation., Agribusiness,

    Involvement of the subthalamic nucleus in impulse control disorders associated with Parkinson’s disease

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    Behavioural abnormalities such as impulse control disorders may develop when patients with Parkinson’s disease receive dopaminergic therapy, although they can be controlled by deep brain stimulation of the subthalamic nucleus. We have recorded local field potentials in the subthalamic nucleus of 28 patients with surgically implanted subthalamic electrodes. According to the predominant clinical features of each patient, their Parkinson’s disease was associated with impulse control disorders (n = 10), dyskinesias (n = 9) or no dopaminergic mediated motor or behavioural complications (n = 9). Recordings were obtained during the OFF and ON dopaminergic states and the power spectrum of the subthalamic activity as well as the subthalamocortical coherence were analysed using Fourier transform-based techniques. The position of each electrode contact was determined in the postoperative magnetic resonance image to define the topography of the oscillatory activity recorded in each patient. In the OFF state, the three groups of patients had similar oscillatory activity. By contrast, in the ON state, the patients with impulse control disorders displayed theta-alpha (4–10 Hz) activity (mean peak: 6.71 Hz) that was generated 2–8mm below the intercommissural line. Similarly, the patients with dyskinesia showed theta-alpha activity that peaked at a higher frequency (mean: 8.38 Hz) and was generated 0–2mm below the intercommissural line. No such activity was detected in patients that displayed no dopaminergic side effects. Cortico-subthalamic coherence was more frequent in the impulsive patients in the 4–7.5 Hz range in scalp electrodes placed on the frontal regions anterior to the primary motor cortex, while in patients with dyskinesia it was in the 7.5–10 Hz range in the leads overlying the primary motor and supplementary motor area. Thus, dopaminergic side effects in Parkinson’s disease are associated with oscillatory activity in the theta-alpha band, but at different frequencies and with different topography for the motor (dyskinesias) and behavioural (abnormal impulsivity) manifestations. These findings suggest that the activity recorded in parkinsonian patients with impulse control disorders stems from the associative-limbic area (ventral subthalamic area), which is coherent with premotor frontal cortical activity. Conversely, in patients with L-dopa-induced dyskinesias such activity is recorded in the motor area (dorsal subthalamic area) and it is coherent with cortical motor activity. Consequently, the subthalamic nucleus appears to be implicated in the motor and behavioural complications associated with dopaminergic drugs in Parkinson’s disease, specifically engaging different anatomo-functional territories

    Contaminación de agua superficial de la periferia urbana de Puerto Maldonado, al sureste de la amazonia peruana

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    The aim of this study was to evaluate the contamination of surface waters in the urban periphery of Puerto Maldonado (Peruvian Amazon), using biological, physicochemical, and microbiological analyses. The water samples were collected in six water bodies (two rivers, three streams and one lake). The physicochemical parameters of each study site did not exceed the limits of the Peruvian Environmental Quality Standard (ECA), except for dissolved oxygen in rivers near urban areas. Pollution of water resources is related to raw sewage and rainwater runoff. Thus, the highest points of faecal contamination were in rivers near urban areas, exceeding the threshold established by the ECA for the conservation of the aquatic environment (CFU ml-1 >2000). In the Madre de Dios River, the concentration of faecal coliforms exceeded the maximum allowed by the ECA by 75 fold, indicating that the Tambopata and Madre de Dios rivers of Puerto Maldonado are heavily contaminated.El objetivo del estudio fue evaluar la contaminación de aguas superficiales en la periferia urbana de Puerto Maldonado (amazonia peruana), utilizando análisis biológicos, fisicoquímicos y microbiológicos. Las muestras de agua se colectaron en seis cuerpos de agua (dos ríos, tres quebradas y un lago). Los parámetros fisicoquímicos de cada sitio de estudio no superaron los límites del Estándar de Calidad Ambiental peruano (ECA), excepto el oxígeno disuelto en ríos cercanos a zonas urbanas. La contaminación de los recursos hídricos está relacionada con los vertidos de aguas residuales y la escorrentía de aguas pluviales. Así, los mayores puntos de contaminación fecal fueron en los ríos cercanos a las zonas urbanas, superando el límite establecido por el ECA para la conservación del medio acuático (UFC ml-1 >2000). En el río Madre de Dios, la concentración de coliformes fecales superó en 75 veces al máximo permitido por el ECA, indicando que los ríos Tambopata y Madre de Dios de Puerto Maldonado están fuertemente contaminados

    Martian Atmospheric Aerosols Composition and Distribution Retrievals During the First Martian Year of NOMAD/TGO Solar Occultation Measurements: 2. Extended Results, End of MY 34 and First Half of MY 35

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    This is the second part of Stolzenbach et al. (2023, https://doi.org/10.1029/2022JE007276), named hereafter Paper I, extends the period to the end of MY 34 and the first half of MY 35. This encompasses the end phase of the MY 34 Global Dust Storm (GDS), the MY 34 C-Storm, the Aphelion Cloud Belt (ACB) season of MY 35, and an unusual early dust event of MY 35 from LS_S 30° to LS_S 55°. The end of MY 34 overall aerosol size distribution shows the same parameters for dust and water ice to what was seen during the MY 34 GDS. Interestingly, the layered water ice vertical structure of MY 34 GDS disappears. The MY 34 C-Storm maintains condition like the MY 34 GDS. A high latitude layer of bigger water ice particles, close to 1 μm, is seen from 50 to 60 km. This layered structure is linked to an enhanced meridional transport characteristic of high intensity dust event which put the MY 34 C-Storm as particularly intense compared to non-GDS years C-Storms as previously suggested by Holmes et al. (2021, https://doi.org/10.1016/j.epsl.2021.117109). Surprisingly, MY 35 began with an unusually large dust event (Kass et al., 2020, https://ui.adsabs.harvard.edu/abs/2020AGUFMP039…01K) found in the Northern hemisphere during LS_S 35° to LS_S 50°. During this dust event, the altitude of aerosol first detection is roughly equal to 20 km. This is close to the values encountered during the MY 34 GDS, its decay phase and the C-Storm of the same year. Nonetheless, no vertical layered structure was observed
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