Resumen Objetivo: La cancerificación es una complicación infrecuente pero grave de la enfermedad por sinus pilonidal. Intentaremos determinar los factores que influyen en el pronóstico de la enfermedad neoplásica basándonos en hallazgos clínicos e histopatológicos. Material y métodos: retrospectivamente se revisan pacientes diagnosticados de malignización de sinus pilonidal en nuestra institución del 2000 a 2019. Resultados: fueron recopilados los casos de siete varones con una media de edad al diagnóstico de 64.8 años. El promedio entre el inicio de los síntomas de sinus pilonidal y el diagnóstico del tumor fue de 33.7 años. Los pacientes con un patrón ulcerativo en el tumor primario presentaron todos invasión perineural, infiltración de estructuras profundas y diseminación a linfáticos regionales. Todos estos pacientes fallecieron en una media de 7 meses. Por el contrario, los pacientes que mostraban un patrón exofítico, no presentaron invasión local o afectación de los linfáticos regionales. Todos estos casos sobrevivieron, con una media de seguimiento de 70.5 meses. Conclusiones: tumores primarios ulcerativos claramente presentan un peor pronóstico que los casos de morfología exofítica. Factores como la infiltración perineural, la invasión local de estructuras profundas o la afectación de los ganglios linfáticos regionales van ligados a una disminución dramática en la supervivencia.

Abstract Introduction: Neoplastic degeneration is an uncommon but extremely serious complication of pilonidal sinus (PS) disease. We pretend to determine the factors that influence in the prognosis of the neoplastic disease assessing clinical features and histological findings. Materials and Methods: We retrospectively studied the patients diagnosed of malignization of PS in our institution from 2000 to 2019. Results: Seven male patients with a mean age at diagnosis of 64.8 years old were collected. Average time between the initial symptoms of PS disease and the tumor diagnosis was 33.7 years. The patients presenting an ulcerative pattern in the primary tumor showed in all the cases perineural invasion, local deep structures infiltration, and neoplastic dissemination to the regional lymph nodes. All these patients died in an average time of 7 months. On the other hand, patients with exophytic patterns in the primary tumor did not present local invasion or regional nodes affectation. All the cases survive with an average follow-up of 70.5 months. Conclusions: Ulcerated lesions clearly show a worse prognosis than tumors with exophytic morphology. Factors as perineural infiltration, local deep structures infiltration, or regional lymph node involvement dramatically decrease survival rates.

Resumen: El objetivo de este estudio fue evaluar el crecimiento y producción de biomasa de variedades de nopal en diferentes contenidos de humedad del suelo como alternativa de producción forrajera. Se usó un diseño experimental de bloques al azar en un arreglo de parcelas divididas con tres repeticiones. Las parcelas grandes fueron los contenidos de humedad edáfica: muy favorable (22 - 27%), favorable (16 - 21%) y desfavorable (10 - 15%); las parcelas chicas correspondieron a las variedades de nopal: Chapingo (Ch) Narro (N) y Escobar (E). La variedad Chapingo fue estadísticamente mayor (P ≤ 0.05) en ancho y grosor de cladodios en los contenidos de humedad del suelo favorable y muy favorable, con valores de 15.7 y 1.1 cm y 15.2 y 1.0 cm, respectivamente; las variedades Escobar y Narro fueron las que registraron mayor contenido relativo de agua (CRA) en los contenidos de humedad favorable y desfavorable, con valores de 78.1 y 63%, respectivamente. El índice de clorofila no varió por efecto de ninguno de los factores variación probados en este estudio. La variedad Narro fue la de mejor productividad en el contenido más favorable de humedad del suelo, con valores de 1.77 Kg y 173.5 g de biomasa fresca y seca por planta, equivalente a 11.8 y 1.15 t ha-1 de biomasa fresca y seca, respectivamente, en corte de cladodios después de ocho meses de realizado el trasplante.

Abstract: The objective of this study was to evaluate the growth and biomass production of Opuntia varieties in different soil moisture content as an alternative for forage production. A randomized block experimental design was used in an arrangement of split plots with three replications. The large plots were the soil moisture content: very favorable (22 - 27%), favorable (16 - 21%) and unfavorable (10-15 %); the small plots corresponded to the varieties of nopal: Chapingo (Ch) Narro (N) and Escobar (E). Chapingo variety was statistically higher (P ≤ 0.05) in width and thickness of cladodes in the favorable and very favorable soil moisture content, with values of 15.7 and 1.1 cm and 15.2 and 1.0 cm, respectively; Escobar and Narro varieties were the ones that registered the highest relative water content (RWC) in the favorable and unfavorable moisture content, with values of 78.1 and 63%, respectively. The chlorophyll index did not change due to the effect of any of the variation factors of this study. Narro variety was the one with the best productivity in the soil moisture content more favorable, with values of 1.77 kg and 173.5 g of fresh and dry biomass per plant, equivalent to 11.8 and 1.15 t ha-1 of fresh and dry biomass, respectively, in cladode cut after eight months after the transplant.

Abstract Objective: To analyze the association of health risk behaviors in the framework of the Problem Behavior Theory. Methods: 524 adolescents (Mage= 16.7, SD = 1.6) completed an online questionnaire. Through Exploratory Factor Analysis, six behaviors were studied: drunkenness, tobacco and hashish use, sensation-seeking, unsafe sex andunsafe road behavior. Results: From middle adolescence (ages 16-17), behavioral grouping was consistent with “unconventionality” dimension identified by Jessor. Its prevalence increased at the end of compulsory education. Conclusion: This grouping suggests the simultaneous prevention of such behaviors. Since these behaviors help adolescents gain personal autonomy and relate to their friends, their prevention should not be limited to reporting the risks that cause. Promoting prosocial behaviors (eg, participating in school and community life) can help adolescents to live their development stage in a healthy way.

Objetivo principal: Analizar la asociación de conductas de riesgo para la salud en el marco de la Teoría de la Conducta Problema. Metodología: 524 adolescentes (Medad=16,7; DT = 1,6) cumplimentaron un cuestionario online. Mediante Análisis Factorial Exploratorio se estudiaron seis conductas: borracheras, consumos de tabaco y hachís, búsqueda de sensaciones, sexo sin protección y comportamiento vial inseguro. Resultados principales: En la adolescencia intermedia (edades 16-17) la agrupación resultó compatible con la dimensión “no convencionalidad” identificada por Jessor. Su prevalencia aumentó al finalizar la educación obligatoria. Conclusión: Esta agrupación aconseja la prevención simultánea de dichas conductas. Dado que estos comportamientos ayudan a los adolescentes a ganar autonomía personal y relacionarse con sus iguales, su prevención no debe limitarse a informar sobre los riesgos que ocasionan. Promover conductas prosociales (p.ej., participar en la vida escolar y comunitaria) puede ayudar a los adolescentes a vivir de manera saludable su transición evolutiva.

ABSTRACT Stock discrimination is essential for biomass population assessment and essential for the fisheries management. The analysis of shape differences in anatomical structures (e.g., body shape, otoliths, scales) has been relevant issue in the study of population structure. We evaluated the hypothesis on the existence of a stock-structured population of Pacific thread herring Opisthonema libertate in the northwestern coast of Mexico. Geometric morphometric methods were used to analyze body and otolith shape. Samples come from at three commercial fishery-landing sites: Magdalena Bay, Guaymas, and Mazatlan, Mexico. Results based on body and otolith shape support the existence of different morphotypes by location. Body shape allowed better discrimination than otolith shape. The differences observed between the phenotypic stocks suggest seasonal movements, which are linked to the marine current system in this region, particularly to the California Current and the North Equatorial Counter Current.

Resumen Lo que se presenta en este documento es una experimentación sobre el desarrollo y los resultados de las pruebas realizadas de una aplicación para computadora, enfocadas a personas con discapacidad visual. Los objetivos del sistema interactivo son: dar a conocer algunos lugares del estado de Aguascalientes, México; y fortalecer la memoria del usuario ciego. El propósito de este artículo es que mediante la construcción del sistema y las pruebas realizadas se da a conocer el grado de interactividad para personas ciegas. El construir aplicaciones con calidad enfocada a la interactividad es importante, ya que, para personas con discapacidad, puede mejorar el grado de uso de las tecnologías (dispositivos móviles). Para determinar la calidad es necesario conocer las características que debe de tener este tipo de aplicaciones, como lo son: pantalla grande, teclado adecuado, ergonomía, entre otras [1], dependiendo del tipo de discapacidad al que se esté refiriendo, es decir, se debe de caracterizar la aplicación para poder determinar cómo desarrollar la aplicación y la medición de la calidad mediante el grado de interacción obtenido. La principal aportación de este trabajo es mostrar los resultados obtenidos del grado de interactividad del sistema al ser utilizado por personas ciegas, así como mostrar parte del proceso de producción de software en el trabajo en equipos definido por Watts Humphrey utilizado para la construcción de la aplicación (TSP) [2].

Abstract This document presents the experimentation, development and results of testing conducted on a computer application designed for visually impaired people. The interactive system aims to promote some places in the State of Aguascalientes, Mexico, and improve the memory of blind users. The purpose of this article is to describe the construction of the system and the testing conducted to measure the degree of interactivity with blind people. Creating interactivity-focused applications is important since it can improve the degree of technology usage (mobile devices) of people with disabilities. To assess the quality of this type of software, the specifications they should meet need to be established. They involve big screens, adapted keyboards and ergonomics [1] and depend on the type of disability being addressed. Therefore, they should be characterized to determine how to develop them and assess their quality with the degree of interaction obtained. The main contribution of this work is presenting the results of the degree of interactivity of the system when used by blind people and detailing part of the Team Software Process (TSP) defined by Watts Humphrey and adopted for developing the application [2].

Abstract The objective of this research work was to analyze the pertinence of a set of design patterns for mobile groupware applications. The pertinence of said contribution was supported by 11 participant members of an educational support group (USAER). The perception of expert users is commonly used in Human-Computer Interaction to improve and validate design strategies such as the proposed one. In this case the feedback provided by the participants helped to ensure that the knowledge offered by the set of patterns is adequate and accurate. A distilled feedback would lead to well-designed user interfaces for mobile groupware applications.

Staphylococcus aureus es un importante patógeno involucrado en una serie de infecciones cuyo impacto se incrementa por sus múltiples factores de virulencia y su resistencia a los antimicrobianos. La resistencia a clindamicina inducida por eritromicina constituye un problema creciente en diversas partes del mundo. Este estudio fue de tipo retrospectivo y se analizó el comportamiento frente a los antimicrobianos de 4307 cepas de Staphylococcus aureus aisladas en un hospital de la ciudad de Maracaibo entre enero 2006 y diciembre de 2013. Se determinó la frecuencia de resistencia a clindamicina inducida por eritromicina, su asociación con la resistencia a oxacilina y el origen biológico de las muestras a partir de las cuales se aisló el microorganismo. La susceptibilidad a oxacilina se comprobó mediante el método de difusión con discos en agar y la resistencia inducida a clindamicina usando la prueba D-test. Se detectaron 60 cepas D-Test positivo (1,39%), de las cuales 38(63,33%) fueron sensibles a meticilina y 22 cepas fueron resistentes (36,67%). La resistencia total a clindamicina (constitutiva e inducida) representó el 31,43% (1354) del total de cepas evaluadas. La frecuencia de resistencia inducida a clindamicina en cepas de Staphylococcus aureus en la localidad es aún baja tanto en cepas sensibles como resistentes a meticilina.

Staphylococcus aureus is an important pathogen involved in a series of infections whose impact is increased by its multiple factors of virulence and antimicrobial resistance. Erythromycin-induced clindamycin resistance is a growing problem in various parts of the world. This study was retrospective and analyzed the behavior in response to antimicrobials of 4307 strains of Staphylococcus aureus isolated in a hospital in the city of Maracaibo between January 2006 and December 2013. The frequency of erythromycin-induced clindamycin resistance, its association with resistance to oxacillin and the biological origin of the samples from which the microorganism was isolated were determined. Susceptibility to oxacillin was checked by diffusion method with disk agar and the induced clindamycin resistance was evaluated using the D-test. 60 D-Test positive strains were detected (1.39%), of which 38 (63.33%) were sensitive to methicillin and 22 strains were resistant (36.67%. The total resistance to clindamycin (constitutive and induced) represented 31.43% (1354) of the total number of strains tested. The frequency of induced resistance to clindamycin in Staphylococcus aureus strains in the locality is still low for both methicillin sensitive and resistant strains.

Introduction: Persea americana Mill. (avocado) and Musa x paradisiaca L. (banana) are medicinal plants with traditional uses in folk medicine. Reports refer to the beneficial effects of a decoction of fresh leaves of avocado in the treatment of urinary infection, coughing and bronchitis. Decoction of banana fresh leaves is used to treat the flu, coughing and inflammation. This has been documented by TRAMIL surveys. The preclinical information found in the databases SciELO, CUMED, LIS CUBA and MEDLINE was not sufficient to validate the uses listed above. Objectives: evaluate the preclinical peripheral and central analgesic activity of a 30 % decoction of fresh leaves of Persea americana Mill. (avocado) and Musa x paradisiaca L. (banana). Methods: fresh leaves of P. americana and M. paradisiaca were collected and 30 % decoctions were prepared. Peripheral analgesic activity was evaluated with the acetic acid induced writhing model (writhing test), whereas central analgesic activity was assessed with the tail flick model in mice by immersion in 55 ºC water. The doses used were 1, 5 and 10 grams of plant material / kg of body weight. Results: decoctions of fresh leaves of P. americana and M. paradisiaca at the study doses significantly inhibited the painful response induced by acetic acid with p=6.909e-08 and p=2.842e-03, respectively. In the tail flick evaluation the decoction of fresh leaves of P. americana had a significant non-dose dependent response at 5g/kg with p=7.018e-03. A significant response was not obtained from the other doses studied or from the M. paradisiaca decoction. Conclusions: results permit the preclinical validation of the peripheral analgesic activity of the decoction of fresh leaves of P. americana (avocado) and M. paradisiaca (banana), as well as the central analgesic activity of P. americana, validating the traditional use of both plants.

Introducción: Persea americana Mill. (aguacate) y Musa x paradisiaca L. (plátano), son dos plantas medicinales que entre sus usos tradicionales reportados, se cita, el efecto beneficioso de la decocción de las hojas frescas de aguacate para la infección urinaria, tos, bronquitis y las de plátano para la gripe, tos e inflamación. Documentado por las encuestas TRAMIL. No se encontró información preclínica suficiente en las bases de datos: SciELO, CUMED, LIS CUBA y MEDLINE para validar sus usos. Objetivos: evaluar la actividad analgésica periférica y central preclínicas de la decocción al 30 % de hojas frescas de Persea americana Mill. (aguacate) y Musa x paradisiaca L. (plátano). Métodos: se colectaron las hojas frescas de P. americana y M. paradisiaca y se realizaron las decocciones al 30 %. Se evaluó la actividad analgésica periférica mediante el modelo de contorsiones inducidas por ácido acético(writhing test), y la actividad analgésica central fue evaluada aplicando el modelo de retirada de la cola por inmersión en agua 55 ºC (tail flick) en ratones, con dosis de 1, 5, y 10 gramos de material vegetal/kg de peso corporal. Resultados: las decocciones de hojas frescas de P. americana y M. paradisiaca a las dosis estudiadas, inhibieron de forma significativa la respuesta dolorosa inducida por ácido acético con p=6,909e-08 y p=2,842e-03respectivamente. En la evaluación del tail flick, la decocción de hojas frescas de P. americana, tuvo una respuesta significativa no dosis dependiente a (5g/kg), con una p=7,018e-03; las otras dosis estudiadas y la decocción de M. paradisiaca no tuvieron respuesta significativa. Conclusiones: los resultados obtenidos permiten realizar la validación preclínica de la actividad analgésica periférica de la decocción de hojas frescas P. americana (aguacate) y M. paradisiaca (plátano), así como de la actividad analgésica central de P. americana, lo que avala su uso tradicional.

Analysis of wild phyllosoma of Panulirus inflatus (Bouvier, 1895) and P. gracilis Streets, 1871 determined the morphological structures having taxonomic value for differentiation of the two species, in addition to the structures described previously. Of 54 phyllosoma, species identity was confirmed by PCR-restriction fragment length polymorphism (RFLP) on 42 P. inflatus and 4 P. gracilis, for which morphology and morphometric measurements were taken. Morphological analysis found subexopodal spines, spines at the base of pereopods 1 and 2, and the mandibles are structures of taxonomic value for differentiating the two species. Morphometric data did not allow differentiation.

This paper presents numerical results of stress concentration factors for plates perforated by corrosion. Evidence from 25 plates with corrosion perforation considered show that typical shapes may be characterized as a deviation from an ellipse or from a circle. In order to model typical perforations created by this type of corrosion, holes with non-circular boundaries have been considered in the form of cosine shape and variations from it. Two load cases are investigated: uniaxial and shear stress fields in an elastic plane stress problem. The influence of the amplitude of deviation with respect to an ellipse or circle and the local curvature of the internal boundary of the hole are studied. A simplified model of an equivalent ellipse originally proposed by Nishida is shown to provide good estimates for stress concentration factors for a range of shapes induced by corrosion.