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Abstract The objective of this research is to present a comparative analysis using various lengths of time windows (TW) during emotion recognition, employing machine learning techniques and the portable wireless sensing device EPOC+. In this study, entropy will be utilized as a feature to evaluate the performance of different classifier models across various TW lengths, based on a dataset of EEG signals extracted from individuals during emotional stimulation. Two types of analyses were conducted: between-subjects and within-subjects. Performance measures such as accuracy, area under the curve, and Cohen's Kappa coefficient were compared among five supervised classifier models: K-Nearest Neighbors (KNN), Support Vector Machine (SVM), Logistic Regression (LR), Random Forest (RF), and Decision Trees (DT). The results indicate that, in both analyses, all five models exhibit higher performance in TW ranging from 2 to 15 seconds, with the 10 seconds TW particularly standing out for between-subjects analysis and the 5-second TW for within-subjects; furthermore, TW exceeding 20 seconds are not recommended. These findings provide valuable guidance for selecting TW in EEG signal analysis when studying emotions.

Resumen El objetivo de esta investigación es presentar un análisis comparativo empleando diversas longitudes de ventanas de tiempo (VT) durante el reconocimiento de emociones, utilizando técnicas de aprendizaje automático y el dispositivo de sensado inalámbrico portátil EPOC+. En este estudio, se utilizará la entropía como característica para evaluar el rendimiento de diferentes modelos clasificadores en diferentes longitudes de VT, basándose en un conjunto de datos de señales EEG extraídas de individuos durante la estimulación de emociones. Se llevaron a cabo dos tipos de análisis: entre sujetos e intra-sujetos. Se compararon las medidas de rendimiento, tales como la exactitud, el área bajo la curva y el coeficiente de Cohen's Kappa, de cinco modelos clasificadores supervisados: K-Nearest Neighbors (KNN), Support Vector Machine (SVM), Logistic Regression (LR), Random Forest (RF) y Decision Trees (DT). Los resultados indican que, en ambos análisis, los cinco modelos presentan un mayor rendimiento en VT de 2 a 15 segundos, destacándose especialmente la VT de 10 segundos para el análisis entre los sujetos y 5 segundos intrasujetos; además, no se recomienda utilizar VT superiores a 20 segundos. Estos hallazgos ofrecen una orientación valiosa para la elección de las VT en el análisis de señales EEG al estudiar las emociones.

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Infection with high-risk human papillomaviruses like HPV-16 and HPV-18 is highly associated with the development of cervical and other cancers. Malignant transformation requires viral oncoproteins E5, E6 and E7, which promote cell proliferation and increase DNA damage. Oxidative stress and hypoxia are also key factors in cervical malignant transformation. Increased levels of reactive species of oxygen (ROS) and nitrogen (RNS) are found in the hypoxic tumor microenvironment, promoting genetic instability and invasiveness. In this work, we studied the combined effect of E5, E6 and E7 and hypoxia in increasing oxidative stress and promoting DNA damage and nuclear architecture alterations. HaCaT cells containing HPV-18 viral oncogenes (HaCaT E5/E6/E7-18) showed higher ROS levels in normoxia and higher levels of RNS in hypoxia compared to HaCaT parental cells, as well as higher genetic damage in hypoxia as measured by γH2AX and comet assays. In hypoxia, HaCaT E5/E6/E7-18 increased its nuclear dry mass and both cell types displayed marked heterogeneity in nuclear dry mass distribution and increased nuclear foci. Our results show contributions of both viral oncogenes and hypoxia to oxidative stress, DNA damage and altered nuclear architecture, exemplifying how an altered microenvironment combines with oncogenic transformation to promote tumor progression.

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There exist several methods aimed at human-robot physical interaction (HRpI) to provide physical therapy in patients. The use of haptics has become an option to display forces along a given path so as to it guides the physiotherapist protocol. Critical in this regard is the motion control for haptic guidance to convey the specifications of the clinical protocol. Given the inherent patient variability, a conclusive demand of these HRpI methods is the need to modify online its response with neither rejecting nor neglecting interaction forces but to process them as patient interaction. In this paper, considering the nonlinear dynamics of the robot interacting bilaterally with a patient, we propose a novel adaptive control to guarantee stable haptic guidance by processing the causality of patient interaction forces, despite unknown robot dynamics and uncertainties. The controller implements radial basis neural network with daughter RASP1 wavelets activation function to identify the coupled interaction dynamics. For an efficient online implementation, an output infinite impulse response filter prunes negligible signals and nodes to deal with overparametrization. This contributes to adapt online the feedback gains of a globally stable discrete PID regulator to yield stiffness control, so the user is guided within a perceptual force field. Effectiveness of the proposed method is verified in real-time bimanual human-in-the-loop experiments.

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Introducción: la trombosis venosa profunda (TVP) es una entidad común que afecta principalmente el sistema venoso profundo de los miembros inferiores, para el cual se han desarrollado múltiples escalas de predicción clínica, las cuales han sido construidas y validadas en pacientes ambulatorios y hospitalizados. Objetivos: validar cinco escalas de predicción clínica para TVP en pacientes atendidos en un centro de tercer nivel en la sabana de Bogotá, Colombia. Métodos: se llevó a cabo un estudio de corte transversal con análisis de prueba diagnóstica en sujetos con sospecha de TVP, incluyendo aquellos que contaran con la realización de ecografía Doppler venosa de miembros inferiores. Se calculó el rendimiento de cinco escalas de predicción clínica para TVP (Wells clásico y modificado, Oudega, CEBI y Constans) para pacientes ambulatorios u hospitalizados, individualizando la población en la que fueron validadas. Resultados: ingresaron al análisis 974 pacientes, de estos 485 (49,7 %) presentaron TVP. La escala de Constans tuvo un mejor rendimiento diagnóstico entre los pacientes hospitalizados y ambulatorios, con un área bajo la curva ROC de 0,73 (95 % 0,70-0,78) al compararla con Wells clásico, Wells modificado, Oudega y CEBI. Al comparar el rendimiento de Constans en ambos grupos de pacientes por separado, también se observó un mejor rendimiento con respecto a las demás escalas. Conclusión: la escala de Constans presenta un mejor rendimiento diagnóstico comparado con las demás escalas al ser aplicada en paciente hospitalizados y ambulatorios.

Summary Introduction: The deep vein thrombosis (DVT) is a common entity that mainly affects the deep venous system of the lower limbs, for which multiple clinical prediction scales have been developed, which have been constructed and validated in outpatients and inpatients. Objetives: We aimed to validated five clinical prediction scores for the diagnosis of lower limb DVT in patients from La Sabana de Bogota, Colombia. Methods: A cross-sectional study with analysis of a diagnostic test was carried out in patiens with suspected deep vein thrombosis, including those who had venous Doppler ultrasound of the lower limbs for suspected DVT. The performance of five clinical prediction scales for DVT (classic and modified Wells, Oudega, CEBI and Constans) for outpatients and inpatients was calculated in those scores who are validated in both populations and only in ambulatory or hospitalized patients for those that are specific scores. Results: Nine hundred seventy-four patients were entered into the analysis, of which 485 (49.7%) presented DVT. The Constans scale had a better diagnostic performance among inpatients and outpatients with an area under the ROC curve of 0.73 (95% 0.70-0.78) when compared with classic Wells, modified Wells, Oudega and CEBI. When we compared Constans performance in both groups of patients separately, we observed better performance with respect to the other scores. Conclusion: The Constans scale presents a better diagnostic performance compared to the other scales when applied to inpatients and outpatients.

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SIGNIFICANCE: Three-dimensional (3D) visualization of multicellular tumor spheroids (MCTS) in fluorescence microscopy can rapidly provide qualitative morphological information about the architecture of these cellular aggregates, which can recapitulate key aspects of their in vivo counterpart. AIM: The present work is aimed at overcoming the shallow depth-of-field (DoF) limitation in fluorescence microscopy while achieving 3D visualization of thick biological samples under study. APPROACH: A custom-built fluorescence microscope with an electrically focus-tunable lens was developed to optically sweep in-depth the structure of MCTS. Acquired multifocus stacks were combined by means of postprocessing algorithms performed in the Fourier domain. RESULTS: Images with relevant characteristics as extended DoF, stereoscopic pairs as well as reconstructed viewpoints of MCTS were obtained without segmentation of the focused regions or estimation of the depth map. The reconstructed images allowed us to observe the 3D morphology of cell aggregates. CONCLUSIONS: Computational multifocus fluorescence microscopy can provide 3D visualization in MCTS. This tool is a promising development in assessing the morphological structure of different cellular aggregates while preserving a robust yet simple optical setup.

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Free fatty acid receptor 1 phosphorylation sites were studied using mutants, including a) a mutant with T215V in the third intracellular loop (3IL), b) another with changes in the carboxyl terminus (C-term): T287V, T293V, S298A, and c) a mutant with all of these changes (3IL/C-term). Agonist-induced increases in intracellular calcium were similar between cells expressing wild-type or mutant receptors. In contrast, agonist-induced FFA1 receptor phosphorylation was reduced in mutants compared to wild type. Phorbol ester-induced FFA1 receptor phosphorylation was rapid and robust in cells expressing the wild-type receptor and essentially abolished in the mutants. Agonist-induced ERK 1/2 phosphorylation and receptor internalization were decreased in cells expressing the mutant receptors compared to those expressing the wild-type receptor. Our data suggest that the identified sites might participate in receptor phosphorylation, signaling, and internalization.

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The lysophosphatidic acid 3 receptor (LPA3) participates in different physiological actions and in the pathogenesis of many diseases through the activation of different signal pathways. Knowledge of the regulation of the function of the LPA3 receptor is a crucial element for defining its roles in health and disease. This review describes what is known about the signaling pathways activated in terms of its various actions. Next, we review knowledge on the structure of the LPA3 receptor, the domains found, and the roles that the latter might play in ligand recognition, signaling, and cellular localization. Currently, there is some information on the action of LPA3 in different cells and whole organisms, but very little is known about the regulation of its function. Areas in which there is a gap in our knowledge are indicated in order to further stimulate experimental work on this receptor and on other members of the LPA receptor family. We are convinced that knowledge on how this receptor is activated, the signaling pathways employed and how the receptor internalization and desensitization are controlled will help design new therapeutic interventions for treating diseases in which the LPA3 receptor is implicated.

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FFA4 (Free Fatty Acid receptor 4, previously known as GPR120) is a G protein-coupled receptor that acts as a sensor of long-chain fatty acids, modulates metabolism, and whose dysfunction participates in endocrine disturbances. FFA4 is known to be phosphorylated and internalized in response to agonists and protein kinase C activation. In this paper report the modulation of this fatty acid receptor by activation of receptor tyrosine kinases. Cell-activation with growth factors (insulin, epidermal growth factor, insulin-like growth factor-I, and platelet-derived growth factor) increases FFA4 phosphorylation in a time- and concentration-dependent fashion. This effect was blocked by inhibitors of protein kinase C and phosphoinositide 3-kinase, suggesting the involvement of these kinases in it. FFA4 phosphorylation did not alter agonist-induced FFA4 calcium signaling, but was associated with decreased ERK 1/2 phosphorylation. In addition, insulin, insulin-like growth factor-I, epidermal growth factor, and to a lesser extent, platelet-derived growth factor, induce receptor internalization. This action of insulin, insulin-like growth factor I, and epidermal growth factor was blocked by inhibitors of protein kinase C and phosphoinositide 3-kinase. Additionally, cell treatment with these growth factors induced FFA4-ß-arrestin coimmunoprecipitation. Our results evidenced cross-talk between receptor tyrosine kinases and FFA4 and suggest roles of protein kinase C and phosphoinositide 3-kinase in such a functional interaction.

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Early stages in tumor development involve growth in confined spaces, where oxygen diffusion is limited and metabolic waste products accumulate. This hostile microenvironment imposes strong selective pressures on tumor cells, leading eventually to the survival and expansion of aggressive subclones that condition further tumor evolution. To model features of this microenvironment in vitro, a diffusional barrier can be introduced in the form of a coverslip placed on top of cells, a method termed coverslip hypoxia. Using a variant of this method, with larger volume between coverslip and cells and with oxygen diffusion occurring only through a small hole in the center of the coverslip, we have visualized alterations in LNCaP tumor cells as a function of their distance to the oxygen source at the center. We observed remarkable morphological changes in LNCaP cells as the distance from the center increases, with cells becoming highly spread, displaying dynamic membrane protrusions and occasionally adopting a migratory phenotype. Concomitantly, cells farther from the center displayed marked increases in the hypoxia marker hypoxyprobe, whereas extracellular pH decreased in the same direction. Cells with altered morphology displayed prominent increases in fibrillar actin, as well as swollen mitochondria with distorted cristae and accumulation of neutral lipid-containing intracellular vesicles. These results show that an in vitro microenvironment that models diffusional barriers encountered by tumors in situ can have profound effects on tumor cells. The coverslip hypoxia variant we describe can be used to characterize in vitro the response of tumor cells to environmental conditions that play crucial roles in early tumor development.

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An increase in intracellular Ca2+ concentration ([Ca2+]i) plays a key role in controlling endothelial functions; however, it is still unclear whether endothelial Ca2+ handling is altered by type 2 diabetes mellitus, which results in severe endothelial dysfunction. Herein, we analyzed for the first time the Ca2+ response to the physiological autacoid ATP in native aortic endothelium of obese Zucker diabetic fatty (OZDF) rats and their lean controls, which are termed LZDF rats. By loading the endothelial monolayer with the Ca2+-sensitive fluorophore, Fura-2/AM, we found that the endothelial Ca2+ response to 20 µM and 300 µM ATP exhibited a higher plateau, a larger area under the curve and prolonged duration in OZDF rats. The "Ca2+ add-back" protocol revealed no difference in the inositol-1,4,5-trisphosphate-releasable endoplasmic reticulum (ER) Ca2+ pool, while store-operated Ca2+ entry was surprisingly down-regulated in OZDF aortae. Pharmacological manipulation disclosed that sarco-endoplasmic reticulum Ca2+-ATPase (SERCA) activity was down-regulated by reactive oxygen species in native aortic endothelium of OZDF rats, thereby exaggerating the Ca2+ response to high agonist concentrations. These findings shed new light on the mechanisms by which type 2 diabetes mellitus may cause endothelial dysfunction by remodeling the intracellular Ca2+ toolkit.

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INTRODUCTION: Living with dogs leads one to consider the necessity of identifying canine infections found in the people with whom the dogs live. OBJECTIVE: Dogs which were clinically and serologically positive with the infections Ehirlichia canis, Anaplasma phagocytophilum, Borrelia burgdorferi, and Dirofilaria Immitis were sought. People with the same infections were also identified. MATERIAL AND METHODS: From a population of 80 dogs identified in the villages of San Bartolo Coyotepec and San Agustín Etla (suburbs peripheral to the city of Oaxaca, Mexico), 27 dogs were selected for study, all of which had adenomegaly, hepatomegaly, splenomegaly, and fevers of at least 43° C. Using enzyme immunoassay in this population of dogs and their closest human contacts, antibodies for Ehirlichia canis, Anaplasma phagocytophilum, Borrelia burgdorferi, and the antigen for Dirofilaria immitis were sought. Positive results in humans were confirmed by polymerase chain reaction (PCR). RESULTS: Ten dogs with the clinical signs mentioned above tested positive for antibodies to Ehrlichia canis; two cases tested positive for Anaplasma phagocytophilum; one case tested positive for Dirofilaria Immitis. From human contact, one person tested positive for Ehirlichia canis; this case was confirmed by DNA amplification by means of PCR. CONCLUSION: It is necessary to identify the population of sick dogs in order to reduce related infections in people.

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BACKGROUND: The American Academy of Neurology (AAN) suggested eight quality measures to be observed at every patient visit. The aim of this work is to compare the percentage of documentation of each measure before and after the implementation of a new worksheet in a third-level center. METHODS: Quasi-experimental study including medical records filled by medical school seniors and junior residents supervised by an epileptologist. The authors surveyed 80 consecutive charts of people with epilepsy who were seen in the outpatient clinic before and after the intervention. McNemar change test was used to compare the percentages of documentation of each quality measure-i.e., seizure type and frequency, etiology, EEG, MRI/CT head scans, AED side effects, surgical therapy referral, safety counseling, preconception counseling-and physical exam. Each quality measure was considered to be fulfilled only if it was assessed and properly recorded. RESULTS: Mean age was 35(±13) years, 55% women, mean epilepsy onset at age 18(±15), 82% presented with partial-onset seizures. The reporting rate improved for all quality measures (previous vs new), reaching statistical significance for: seizure type 80vs94% (p < 0.05), AED side effects 8vs24%, etiology 66vs88% (p < 0.01), safety counseling 5vs64%, preconception counseling 4vs20%, and physical exam 63vs94% (p < 0.001). CONCLUSION: A quality-oriented epilepsy worksheet led to a better practice standardization and documentation of AAN standards for diagnostic and counseling purposes. Further evaluations should be undertaken to assess the impact on medical education and patient care.

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The role of Na(+)-Ca(2+) exchanger (NCX) in vascular endothelium is still matter of debate. Depending on both the endothelial cell (EC) type and the extracellular ligand, NCX has been shown to operate in either the forward (Ca(2+) out)- or the reverse (Ca(2+) in)-mode. In particular, acetylcholine (Ach) has been shown to promote Ca(2+) inflow in the intact endothelium of excised rat aorta. Herein, we assessed the involvement of NCX into the Ca(2+) signals elicited by ATP in such preparation. Removal of extracellular Na(+) (0Na(+)) causes the NCX to switch into the reverse-mode and induced an increase in intracellular Ca(2+) concentration ([Ca(2+)](i)), which disappeared in the absence of extracellular Ca(2+), and in the presence of benzamil, which blocks both modes of NCX, and KB-R 7943, a selective inhibitor of the reverse-mode. ATP induced a transient Ca(2+) signal, whose decay was significantly prolonged by 0Na(+), benzamil, DCB, and monensin while it was unaffected by KB-R 7943. Notably, lowering extracellular Na(+) concentration increased the sensibility to lower doses of ATP. These date suggest that, unlike Ach-stimulated ECs, NCX promotes Ca(2+) extrusion when the stimulus is provided by ATP in intact endothelium of rat aorta. These data show that, within the same preparation, NCX operates in both modes, depending on the chemical nature of the extracellular stimulus.

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BACKGROUND: The pharyngocutaneous fistulae is troublesome and the most common complication following total laryngectomy. Our objective was to determine the incidence of pharingocutaneous fistulae after the total laryngectomy in our serie and to make review of the medical literature. METHODS: We made a retrospective study of a serie of 81 consecutive cases of laryngeal carcinoma treated between 1995 and 2008 in our section. Total laryngectomy was performed in 29 cases and 52 patients treated with organ preservation approach, were excluded. In 14 cases, the procedure was combined with radical neck dissection, pharyngeal resection or myocutanenous flaps. Nasogastric tube for feeding in the postoperative period was used in all patients and surgical gastrostomy was performed in 5 cases. RESULTS: Our incidence of fistulas when total laryngectomy was the alone procedure is 20 % and 34.5 % when simultaneous surgical proceedings were associated. Spontaneous closure was noted in 80 % of the cases and the mean hospitalization time was 23 days. CONCLUSIONS: Most of the fistulas can be managed with conservative treatment. Pectoralis major myocutanenous flap is appropriate when conservative treatment has failed. In small fistulas, nasogastric or gastrostomy tube for feeding can be successfully managed in the ambulatory follow up. The cost-benefit relation must be better analyzed.

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BACKGROUND: The overall situation in Guatemala, Central America, regarding programs caring for women's reproductive health has been lagging behind for some decades. Since the year 2000, 56% of Guatemalan families have lived below the poverty line. Guatemala has one of the highest fertility rates (lifetime births per woman) in Latin America and the Caribbean countries, comparable to those observed in less developed countries in Africa. Considering the lack of sex education, poor access to effective contraceptive methods and issues of unwanted pregnancy, Guatemalan women engage in illegal and unsafe abortions, which often causes harm and sometimes death. A key strategy designed to improve women's health is through free and informed access to contraceptive methods that are effective and accepted by Guatemalan women. STUDY DESIGN: From July 1, 2003, to December 31, 2006, specially hired trained facilitators visited 22 public hospitals for 1 week to train corresponding physician staff in postabortion counseling, enabling them to assist patients to select and use an effective contraceptive method. To monitor the progress achieved, the trained facilitators returned 4 weeks later. The main purpose of the training was to focus in strengthening the understanding and technical capacity of the hospital staff to implement postabortion contraceptive counseling and to enable women to obtain an effective contraceptive method prior to hospital discharge. RESULTS: Out of 22 hospitals, 21 managed to improve their record for counseling patients admitted for postabortion complications, from 31% to 96%. Furthermore, the percentage of women being discharged from the hospital with an effective contraceptive method rose from 20% to 64% from 2003 to 2006. CONCLUSION: The successful results obtained during this study to meet postabortion demands by Guatemalan women point out to the urgent need for the government to expand this initiative within the national health system, including health centers nationwide. This is one of the worldwide recommendations previously made by the World Health Organization.

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Introducción. Los restos óseos arcaicos son fuente privilegiada de información biológica y su caracterización genética permite confirmar o descartar filiaciones propuestas por otras aproximaciones científicas. La historia precolombina de los Andes orientales se divide en tres periodos principales: I) un poblamiento temprano por parte de grupos cazadores-recolectores; II) un periodo intermedio (Herrera) de pueblos con agricultura incipiente, y III) un periodo tardío de pueblos chibchas, agrícolas y alfareros (agroalfarero). Objetivo. Analizar el ADN mitocondrial de restos óseos del periodo Herrera. Materiales y métodos. Se analizaron 11 individuos pertenecientes al yacimiento arqueológico Madrid 2-41, con una edad aproximada de 2.000 años. Un fragmento (192 pb) del segmento hipervariable I fue amplificado y secuenciado, siguiendo criterios estrictos de autenticidad deADN arcaico. Las secuencias se compararon con las existentes en bases de datos de Norteamérica y Europa usando herramientas bioinformáticas. Resultados. Todas las secuencias resultaron idénticas y fueron clasificadas como haplogrupo B. Esto puede relacionarse con el tipo de entierro ritual practicado en Madrid 2-41, es decir, probablemente los individuos analizados hagan parte de una familia jerárquicamente importanteen la antigua sociedad Herrera. La búsqueda de secuencias homólogas en las bases de datos estadounidense y europea no arrojó coincidencias exactas, aunque existe el reporte de un individuo amazónico de ~4.000 años de antigüedad (Brasil) cuya secuencia coincide con la hallada en Madrid 2-41.Conclusión. Los individuos del yacimiento arqueológico Madrid 2-41 están estrechamente emparentados entre sí por línea materna y presentan una secuencia aparentemente ausente en poblaciones actuales.

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Diffuse uterine leiomyomatosis is a rare benign entity in gynecology, with only 30 worldwide reports. Its most frequent complications are dissemination into vena cava, cardiac obstruction (right cavities and valves), and diffuse pelvic invasion. We report a case of a 40 years old female with history of pelvic mass resection. During surgery it was found a large abdominal-pelvic mass diffusely invading uterine body, and round and infundibulum-pelvic ligaments. This mass extends itself out of pelvis until aorto-abdominal bifurcation, and has gummatous, elastic, and highly bleeding consistency. Histopathologic report was intravenous leiomyomatosis with benign smooth muscular fibers infiltrating adjacent structures. Its origin was uterine tissue, but it invades, adjacently, all reproductive annexes deforming them anatomy. Its infiltrative quality confers a technical difficulty to surgeon, so he or she will need a multidisciplinary team to establish its treatment.

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Guatemala tiene décadas de retraso en la implementación de adecuados programas que protejan la salud reproductiva de las mujeres. Enfrentadas a la terrible pobreza, el 56% de las familias guatemaltecas vivían por debajo de la línea de pobreza en el año 2000, situación que no ha cambiado y que posiblemente haya empeorado. Más aún, el 16% de las familias estaban en pobreza extrema, dicho en otras palabras, no podían ni adquirir una canasta básica de alimentos. Así también, la mujer guatemalteca, tiene una de las tasas más altas de fertilidad (número de hijos por mujer)...

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