4,213 research outputs found

    Clinical, imaging and genetic analysis of double bilateral radix entomolaris

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    Background: Anatomy describes that first mandibular molars have two roots: 1 mesial, with 2 root canals, and 1 distal, with 1 root canal. The presence of three roots in these teeth is uncommon. Root anatomical variations have an impact, especially in endodontic, where the highest rates of nonsurgical treatment failures are due to the inability to identify and access roots and/or accessory canals. The aim of this research is to report a case of double three-rooted mandibular first molar through clinical, imaging and genetic analysis. Materials and methods: Using a panoramic radiography, the presence of three roots in teeth 36 and 46 was diagnosed in a female patient. Additionally, it was indicated a cone beam computed tomography. Moreover, leukocyte genomic DNA was obtained from a blood sample of the patient to determine her ethnicity through analysis of mitochondrial DNA haplogroups using polymerase chain reaction-length restriction fragment polymorphism (PCR-RFLP). Results: Both molars had three roots, 1 mesial (M), 1 distolingual (DL), also known as radix entomolaris (RE), and a distovestibular (DV). For both teeth, M root had 2 canals, and DV and DL roots presented just 1 canal. Mitochondrial DNA analysis determined presence of haplogroup C, corresponding to Amerindian ethnicity. Conclusions: The presence of RE is uncommon. This case report contributes to describe this rare anatomical variation. To our knowledge, this is the first molecular-genetic study applied to dental anatomy and gives basis to develop future research in the area

    Las redes inalámbricas de área local ("Wi-Fi") en la FCC y el CNAF

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    En los últimos años, las Redes Inalámbricas de Área Local (WLAN, Wireless Local Área Networks) basadas en el estándar IEEE (802.11 [1] y sus derivados ñan conseguido unos altos niveles de implantación y desbordar el ámbito de aplicaciones y servicios para los que fueron inicialmente concebidas. De hecho, que se ñan convertido en un fenómeno tecnológico

    Direct Hydroxylation of Phenol to Dihydroxybenzenes by H2O2 and Fe-based Metal-Organic Framework Catalyst at Room Temperature

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    A semi-crystalline iron-based metal-organic framework (MOF), in particular Fe-BTC, that contained 20 wt.% Fe, was sustainably synthesized at room temperature and extensively characterized. Fe-BTC nanopowders could be used as an efficient heterogeneous catalyst for the synthesis of dihydroxybenzenes (DHBZ), from phenol with hydrogen peroxide (H2O2), as oxidant under organic solvent-free conditions. The influence of the reaction temperature, H2O2 concentration and catalyst dose were studied in the hydroxylation performance of phenol and MOF stability. Fe-BTC was active and stable (with negligible Fe leaching) at room conditions. By using intermittent dosing of H2O2, the catalytic performance resulted in a high DHBZ selectivity (65%) and yield (35%), higher than those obtained for other Fe-based MOFs that typically require reaction temperatures above 70◦C. The long-term experiments in a fixed-bed flow reactor demonstrated good Fe-BTC durability at the above conditionsThe authors thank the financial support by Consejo Nacional de Ciencia y Tecnología (CONACYT) for the grant number 764635 and the project 256296; and to TNM for the supporting project 5627.19.P. Also, to the Spanish Ministerio de Ciencia, Innovación y Universidades (MICINN) and FEDER program (EU) through the projects: CTM2016-76454-R (MICINN) and RTI2018-095052-B-I00 ((MCIU/AEI/FEDER, UE

    Blood pressure reduction due to hemoglobin glycosylation in type 2 diabetic patients

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    Pedro Cabrales1, Miguel A Salazar Vázquez2,3, Beatriz Y Salazar Vázquez3,4, Martha Rodríguez-Morán5, Marcos Intaglietta4, Fernando Guerrero-Romero51La Jolla Bioengineering Institute, La Jolla, California, USA; 2Hospital Regional No. 1, of the Mexican Social Security Institute, Victoria de Durango, Dgo. Mexico; 3Faculty of Medicine and Dept. of Physical Chemistry, Universidad Juárez del Estado de Durango, Victoria de Durango, Dgo. Mexico; 4Department of Bioengineering, University of California, San Diego, La Jolla, California, USA; 5Biomedical Research Unit, of the Mexican Social Security Institute, Victoria de Durango, Dgo. MexicoObjective: To test the hypothesis that glycosylation of hemoglobin constitutes a risk factor for hypertension.Methods: A total of 129 relative uniform diabetic subjects (86 women and 42 men) were enrolled in a cross-sectional study. Exclusion criteria included alcohol consumption, smoking, ischemic heart disease, stroke, neoplasia, renal, hepatic, and chronic inflammatory disease. Systolic and diastolic pressures were recorded in subsequent days and mean arterial blood pressure (MAP) was determined. Hemoglobin glycosylation was measured by determining the percentage glycosylated hemoglobin (HbA1c) by means of the automated microparticle enzyme immunoassay test.Results: MAP was found to be independent of the concentration of HbA1c; however, correcting MAP for the variability in hematocrit, to evidence the level of vasoconstriction (or vasodilatation) showed that MAP is negatively correlated with the concentration of HbA1c (p for trend <0.05), when patients treated for hypertension are excluded from the analysis. Patients treated for hypertension showed the opposite trend with increasing MAP as HbA1c increased (p for the difference in trends <0.05).Conclusions: Glycosylation per se appears to lead to blood pressure reduction in type 2 diabetic patients untreated for hypertension. Treatment for hypertension may be associated with a level of endothelial dysfunction that interferes with the antihypertensive effect of HbA1c.Keywords: diabetes, hemoglobin glycosylation, hypertension, hematocrit, nitric oxid

    Despliegue de redes inalámbricas (WI-FI): planificación radio

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    Desde hace apenas tres años, una tecnología, o quizás sería más exacto, un protocolo de comunicaciones empezó a despuntar con éxito y vistas de un tremendo futuro. Esta tecnología basada en el estándar IEEE 802.11b y conocida como Wi-Fi (“Wireless Fidelity”) ha conseguido unos altos niveles de implantación, desbordar el ámbito de aplicaciones y servicios para los que fue inicialmente concebida y ser un poderoso complemento a otras tecnologías que requieren importantes infraestructuras y altos niveles de inversión

    Periodismo especializado en política y economía en Colombia entre cruces digitales

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    En los últimos años el debate en torno al presente y futuro del periodismo ha estado en el centro de las reflexiones académicas, de las discusiones de pasillo y de las decisiones empresariales. La llegada de los entornos digitales ha incorporado una variable más que increpa al oficio desde su profesionalismo. El texto presenta un conjunto nutrido de reflexiones sobre los efectos de la Internet sobre el periodismo, efectos que según el autor aún no están suficientemente configurados. Lo mejor está aún por verse. La mediología fue la disciplina desde la cual se llevó a cabo la aproximación para este estudio. De origen francés, la mediología desea sacar a la luz los entrecruces entre tecnología y los amplios contextos sociales de cada momento histórico. Entrevistando a casi 50 periodistas de diferentes medios de comunicación del país, el texto logra encontrar las tendencias del periodismo político y económico en lo que el autor denomina su “estado digital”

    Role of antiseptics in the prevention and treatment of infections in nursing homes

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    Inadequate infection control, wound care, and oral hygiene protocols in nursing homes provide challenges to residents’ quality of life. Based on the outcomes from a focus group meeting and a literature search, this narrative review evaluates the current and potential roles of antiseptics within nursing home infection management procedures. We examine contemporary strategies and concerns within the management of meticillin-resistant Staphylococcus aureus (MRSA; including decolonization regimes), chronic wound care, and oral hygiene, and review the available data for the use of antiseptics, with a focus on povidone-iodine. Compared with chlorhexidine, polyhexanide, and silver, povidone-iodine has a broader spectrum of antimicrobial activity, with rapid and potent activity against MRSA and other microbes found in chronic wounds, including biofilms. As no reports of bacterial resistance or cross-resistance following exposure to povidone-iodine exist, it may be preferable for MRSA decolonization compared with mupirocin and chlorhexidine, which can cause resistant MRSA strains. Povidone-iodine oral products have greater efficacy against oral pathogens compared with other antiseptics such as chlorhexidine mouthwash, highlighting the clinical benefit of povidone-iodine in oral care. Additionally, povidone-iodine-based products, including mouthwash, have demonstrated rapid in vitro virucidal activity against SARS-CoV-2 and may help reduce its transmission if incorporated into nursing home coronavirus 2019 control protocols. Importantly, povidone-iodine activity is not adversely affected by organic material, such as that found in chronic wounds and the oral cavity. Povidone-iodine is a promising antiseptic agent for the management of infections in the nursing home setting, including MRSA decolonization procedures, chronic wound management, and oral care.N/

    An expeditious low-cost method for the acoustic characterization of seabeds in a Mediterranean coastal protected area

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    Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGPosidonia oceanica meadows are ecosystem engineers which, despite their ecological relevance, are experiencing habitat fragmentation and area decrease. Cartography and information on the ecological status of these habitats is key to an effective maritime spatial planning and management for habitat conservation. In this work we apply an acoustic methodology to map benthic habitats (substrate and vegetation) in an archipelago of the Natura 2000 Network close to the coast of Murcia (SE Spain) where dense and sparse areas of P. oceanica, and patches of Cymodocea nodosa appear over a sandy and had bottom. The methodology uses dual frequency information (200 kHz and 38 kHz) acquired with a single-beam echosounder to develop a bathymetry, and performs sea bottom and vegetation supervised classifications, using video and scuba diver observations as groundtruthing data. Sea bottom was classified from acoustic features of the first and second 200 kHz echoes into 5 substrate classes using a random forest classifier: sand, fine sand, coarse sand, hard bottoms and hard bottoms with sandy patches. The vegetation was classified from features extracted from the "above-bottom" part of the echo (height and backscattering intensity) in both frequencies, resulting also in a 5 class classification: C. nodosa meadows, dense P. oceanica meadows, dispersed P. oceanica meadows, dense P. oceanica with sand patches, and no-vegetation; according to the random-forest Gini index, 38 kHz features were the most informational variables for this classification. The validation accuracies of both classifications were 85% (substrates) and 70% (vegetation), close to accuracies reported in the literature when using a similar number of classes. The results of this article (including bathymetric, and substrate and vegetation thematic maps), together with the acoustic methodology described and used, are contributions that can improve the continuous monitoring of Mediterranean seagrasses

    El género Elaphrothrips buffa, 1909 (Insecta, Thysanoptera, Tubulifera) en América Central, discusión del concepto de especie y descripción de especies nuevas para Costa Rica

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    Se analiza el concepto de especie dentro del género Elaphrothrips, así como los problemas de criterios taxonómicos relacionados a este grupo. Además, se discuten las variaciones morfológicas del mismo y se presentan las características de los grupos de especies en el género. Se revisó el material de Elaphrothrips que ha sido recolectado y se describen tres especies nuevas procedentes de material recolectado en Costa Rica pero depositado en la colección del Senckenberg Museum en Alemania

    Alzheimer\u27s Disease: From Animal Models to the Human Syndrome

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    Some animal models, genetically modified (such as murine) and sporadic (as others species), enable the study of the origin of specific lesions observed in human neurodegenerative diseases. In particular, Alzheimer\u27s disease (AD) models have been designed to test the hypothesis that certain lesions are associated with functional and morphological changes beginning with memory loss and impairment in activities of daily life. This review compares and evaluates the phenotypes of different AD animal models, on the basis of the specific objectives of each study, with the purpose of encompassing their contributions to the comprehension of the AD signs and symptoms in humans. All these models contribute to the comprehension of the human AD mechanisms regarding the heterogeneity of AD phenotypes: the overlap between AD and age‐related changes, the variability of AD onset (early or late), the probable reactiveness of amyloid‐β and tau proteins, the scarcity of senile plaques and/or neurofibrillary tangles in some AD cases, the spatial correlation of the pathology and cerebral blood vessels, and the immunological responses (microglial aging) and synaptopathy. Altogether, these considerations may contribute to find therapies to treat and prevent this disease
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