Investigation of pathophysiologic trends in Caucasian and Afro-American hypertensives by means of heart rate variability recording during upright tilt-table testing

The incidence of hypertension is more prevalent among the Afro-American population than the Caucasians and there is not a satisfactory explanation for this discrepancy. Heart Rate Variability (HRV) has been demonstrated to reflect the relative activities of the sympathetic (SMP) and parasympathetic (PSMP) divisions of the autonomic nervous system (ANS). This study consisted in comparing the HRV, as well as the blood pressure (BP) of four different groups during up-right tilt table testing. The subjects were grouped by age, gender, race and health condition. Analysis in time and frequency domain was applied to the data. In the frequency domain, the LF and HF bands were studied. In the time domain, a new parameter was proposed to analyze the data. As a result, the ratio of the FIF area, from the supine to the standing positions, was higher in the hypertensive group than the normotensive one, and the ratio of the LF area was higher in the normotensives than the others. On the other hand, Afro-Americans had a higher LF area ratio than Caucasians and a lower HF area ratio

Una propuesta metodológica para la evaluación del proceso de enseñanza-aprendizaje en un ambiente virtual (A methodologica proposal to evaluate teaching-learning process in a virtual environment)

Abstract. This article provides a methodological proposal oriented to optimize the assessment process of a student performance on an on line environment through the application of group communication techniques (advisor-student, student-advisor, studentstudent, student-chat and so on) and widespread use of the new technologies on information and telecommunication as basic tools, based one the process follow-up and statistical data collection from the student´s learning performance and behaviour to enable the construction of significant and reliable indexes thus allowing the advisor a diagnostic on the student´s attitude and performance, allowing him to take on time the adequate preventive/corrective decision measures based on a success/failure tests outputs from the student performance, on a day- to- day basis, on the line environment.Resumen. Este artículo ofrece una propuesta metodológica enfocada a optimizar el proceso de evaluación sobre el aprovechamiento del alumno en un entorno en línea mediante técnicas de comunicación grupal (tutor- alumno, alumno-tutor, alumno-alumno, alumno-chat, programa, etc.) y el uso profuso de las nuevas tecnologías de información y telecomunicación como herramientas básicas, mediante un seguimiento y registro estadístico del aprovechamiento y actitudinal del estudiante, posibilitando así la construcción de índices significativos, seguros y confiables, que permitan al instructor/facilitador disponer de un diagnóstico sobre el comportamiento y actitud del aplicar y aplicar en consecuencia las medidas preventivas/correctivas sobre la conducta continuamente observada del alumno en el entorno en línea

The SuperWASP catalogue of 4963 RR Lyr stars: identification of 983 Blazhko candidates

Aims. We set out to compile a catalogue of RRab pulsating variables in the SuperWASP archive and identify candidate Blazhko effect objects within this catalogue. We analysed their light curves and power spectra for correlations in their common characteristics to further our understanding of the phenomenon. Methods. Pulsation periods were found for each SWASP RRab object using PDM techniques. Low frequency periodic signals detected in the CLEAN power spectra of RRab stars were matched with modulation sidebands and combined with pairs of sidebands to produce a list of candidate Blazhko periods. A novel technique was used in an attempt to identify Blazhko effect stars by comparing scatter at different parts of the folded light curve. Pulsation amplitudes were calculated based on phase folded light curves.Results. The SuperWASP RRab catalogue consists of 4963 objects of which 3397 are previously unknown. We discovered 983 distinct candidates for Blazhko effect objects, 613 of these being previously unknown in the literature as RR Lyrae stars, and 894 are previously unknown to be Blazhko effect stars. Correlations were investigated between the scatter of points on the light curve, the periods and amplitudes of the objects’ pulsations, and those of the Blazhko effect.Conclusions. A statistical analysis has been performed on a large population of Blazhko effect stars from the wide-field SuperWASP survey. No correlations were found between the Blazhko period and other parameters including the Blazhko amplitude, although we confirmed a lower rate of occurrence of the Blazhko effect in long pulsation period objects

Clinical and Genetic Analysis of Costa Rican Patients With Parkinson's Disease

Background: Most research in genomics of Parkinson’s disease (PD) has been done in subjects of European ancestry, leading to sampling bias and leaving Latin American populations underrepresented. We sought to clinically characterize PD patients of Costa Rican origin and to sequence familial PD and atypical parkinsonism-associated genes in cases and controls. Methods: We enrolled 118 PD patients with 97 unrelated controls. Collected information included demographics, exposure to risk and protective factors, and motor and cognitive assessments. We sequenced coding and untranslated regions in familial PD and atypical parkinsonism-associated genes including GBA, SNCA, VPS35, LRRK2, GCH1, PRKN, PINK1, DJ-1, VPS13C, and ATP13A2. Results: Mean age of PD probands was 62.12 ± 13.51 years; 57.6% were male. The frequency of risk and protective factors averaged ∼45%. Physical activity significantly correlated with better motor performance despite years of disease. Increased years of education were significantly associated with better cognitive function, whereas hallucinations, falls, mood disorders, and coffee consumption correlated with worse cognitive performance. We did not identify an association between tested genes and PD or any damaging homozygous or compound heterozygous variants. Rare variants in LRRK2 were nominally associated with PD; six were located between amino acids p.1620 and 1623 in the C-terminal-of-ROC (COR) domain of Lrrk2. Non-synonymous GBA variants (p.T369M, p.N370S, and p.L444P) were identified in three healthy individuals. One PD patient carried a pathogenic GCH1 variant, p.K224R. Discussion: This is the first study that describes sociodemographics, risk factors, clinical presentation, and genetics of Costa Rican patients with PD, adding information to genomics research in a Latino population.Antecedentes: la mayor parte de la investigación en genómica de la enfermedad de Parkinson (EP) se ha realizado en sujetos de ascendencia europea, lo que provoca un sesgo de muestreo y deja a las poblaciones latinoamericanas infrarrepresentadas. Buscamos caracterizar clínicamente a los pacientes con EP de origen costarricense y secuenciar la EP familiar y los genes asociados con el parkinsonismo atípico en casos y controles. Métodos: Inscribimos a 118 pacientes con EP con 97 controles no relacionados. La información recopilada incluyó datos demográficos, exposición a factores de riesgo y de protección, y evaluaciones motoras y cognitivas. Se secuenciaron las regiones codificantes y no traducidas en la EP familiar y los genes asociados con el parkinsonismo atípico, incluidos GBA, SNCA, VPS35, LRRK2, GCH1, PRKN, PINK1, DJ-1, VPS13C y ATP13A2. Resultados: La edad media de los probandos de EP fue de 62,12 ± 13,51 años; El 57,6% eran hombres. La frecuencia de los factores de riesgo y protección promedió ~ 45%. La actividad física se correlacionó significativamente con un mejor rendimiento motor a pesar de años de enfermedad. El aumento de años de educación se asoció significativamente con una mejor función cognitiva, mientras que las alucinaciones, las caídas, los trastornos del estado de ánimo y el consumo de café se correlacionaron con un peor rendimiento cognitivo. No identificamos una asociación entre los genes probados y la EP ni ninguna variante heterocigótica homocigótica o compuesta dañina. Las variantes raras en LRRK2 se asociaron nominalmente con la EP; seis estaban ubicados entre los aminoácidos p.1620 y 1623 en el dominio C-terminal-de-ROC (COR) de Lrrk2. Se identificaron variantes de GBA no sinónimas (p.T369M, p.N370S y p.L444P) en tres individuos sanos. Un paciente con EP portaba una variante patógena de GCH1, p.K224R.Universidad de Costa Rica/[837-B5-304]/UCR/Costa RicaCanadian Consortium on Neurodegeneration in Aging/[]/CCNA/CanadáCanada First Research Excellence Fund/[]/CFREF/CanadáHealthy Brains for Healthy Lives/[]/HBHL/CanadáUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Centro de Investigación en Neurociencias (CIN)UCR::Vicerrectoría de Docencia::Salud::Facultad de Medicina::Escuela de Medicin

Effect of aspirin on the diagnostic accuracy of the faecal immunochemical test for colorectal advanced neoplasia

Background: Aspirin (ASA) is a drug that can cause gastrointestinal lesions and symptoms. Colorectal cancer (CRC) is the most prevalent type of cancer in Western countries. We assessed the effect of aspirin on the diagnostic accuracy of the faecal immunochemical test (FIT) for CRC and/or advanced neoplasia (AN) in patients undergoing colonoscopy for gastrointestinal symptoms. Methods: We conducted a prospective multicentre observational study of diagnostic tests that included patients with gastrointestinal symptoms undergoing colonoscopy between March 2012 and 2014 (the COLONPREDICT study). Symptoms were assessed and a FIT and blood tests assessing haemoglobin and carcinoembryonic antigen (CEA) levels were performed. Results: The study included 3052 patients: A total of 2567 did not take aspirin (non-user group) and 485 (16%) took aspirin (user group). Continuous treatment with ASA did not change the AUC (0.88, 0.82; p = 0.06), sensitivity (92%, 88%; p = 0.5) or specificity (71%, 67%; p = 0.2) of the FIT for CRC detection. Similarly, we found no differences in the AUC (0.81, 0.79; p = 0.6), sensitivity (74%, 75.5%; p = 0.3) or specificity (76%, 73.6%; p = 0.3) for AN detection. Patients with an aspirin use of = 300 mg/day had a lower prevalence of AN and the sensitivity, specificity and AUC for AN for these patients were 54%, 68% and 0.66, significantly lower than for the non-user group (p = 0.03). Conclusions: Aspirin does not modify the diagnostic accuracy of FIT for CRC and/or AN in patients with gastrointestinal symptoms. Aspirin use of = 300 mg/day decreases the accuracy of the test