Tourists perceptions of Caribbean islands facing environmental threats before the COVID-19 health crisis: Holbox Island and Archipelago of Bocas del Toro.

Knowledge gaps exist in the socio-ecological systems of small touristic islands in Latin America. Understanding tourists' perceptions of their environmental knowledge can help plan actions to prevent natural capital loss necessary for local economies. Tourists' perceptions of a touristic hotspot, Holbox Island, were documented. Surveys demonstrated that tourists are aware of their environmental impacts and are interested in minimizing these. Results were compared with results on Bocas del Toro, Panama. Tourists' perceptions had similarities among sites driven by similarities in tourists' populations with a common geographic origin. Tourists lack site-specific knowledge to steer them towards environmentally conscious decisions in both regions. Findings suggest the need to promote local actions to gain tourists' understanding about their destination and support education programs on island conservation. Addressing these needs can help build resilience to overcome the adverse socio-environmental effects of tourism, environmental disasters, and health crises as COVID-19 on small islands.

Condition-dependent female preference for male genitalia length is based on male reproductive tactics.

There is extensive morphological variation of male genitalia across animals with internal fertilization, even among closely related species. Most studies attempting to explain this extraordinary diversity have focused on processes that occur post-copula (e.g. sperm competition, cryptic female choice). Only a few studies have focused on the pre-copula process of female preference. In addition, the extent to which this variation could be associated with the use of different reproductive tactics has yet to be explored. Here, we show that female preference for male genitalia length in two livebearing fishes depends on the type of reproductive tactic of the males being evaluated as well as the body condition of the female. In a species where all males coax females to acquire matings (courters), females preferred males with short genitalia. In a species with genetically influenced alternative reproductive tactics (courter males that only court and produce courter sons, sneaker males that use the coercive tactic of sneak chase and produce sneaker sons), female preference depended on an interaction between male tactic and female condition: females in good condition preferred courter males with short genitalia, and sneaker males with long genitalia. Our results suggest that female preference for male traits favourable to their sons may be an important factor contributing to the diversification of male genitalia. Despite the contrasting selection for genitalia length that our female preference tests suggest, we found no significant differences in genitalia length between coaxing (courters) and coercive (sneakers) males. Our study represents a starting point to more clearly understand the role of alternative reproductive tactics and variation in female mate preference in the evolution of male genitalia.

Homoisoflavanones from Agave tequilana Weber.

Three homoisoflavanones were isolated from the "piña" and leaves of Agave tequilana Weber. The compounds were identified as: 5,7-dihydroxy-3-(4-methoxybenzyl)-chroman-4-one (1), 7-hydroxy-3-(4-hydroxybenzyl)-chroman-4-one (2) and 4'-demethyl-3,9-dihydro-punctatin (3). This is the first phytochemical study carried out to Agave tequilana Weber.

The participation of secondary clinical episodes in the epidemiology of vivax malaria during pre- and post-implementation of focal control in the state of Oaxaca, Mexico.

The participation of vivax malaria secondary clinical was researched in a retrospective cohort of 33,414 confirmed cases occurring between 1994 and 2005 in the state of Oaxaca, Mexico. Secondary episodes occurred in 23.4% of all primary cases. An increase in secondary episodes was associated with primary cases occurring during the dry seasons (risk ratio [RR] = 1.68, 95% CI: 1.45-1.96). The incidence of secondary episodes peaked at an older age, occurred similarly in men and women mostly during low mosquito abundance, and had a uniform distribution among localities. A reduction in secondary episodes was associated with the administration of an increased dose and early administration of primaquine (RR = 0.32, 95% CI: 0.26-0.38). However, limitations to distinguish relapses from re-infections impede assessment of the new treatment effect on relapses and its contribution to malaria control in the area. These findings highlight the need for new therapeutic schemes to radical cure of P. vivax infections and operational research aimed at parasite pool elimination.

[Application of chromoendoscopy to evaluate the severity and interobserver variation in chronic non-specific ulcerative colitis]. / Aplicación de la cromoendoscopia para evaluar la gravedad y variabilidad interobservador en la colitis ulcerativa crónica inespecífica (CUCI).

BACKGROUND: Ulcerative colitis (UC) is a disease of unknown etiology characterized by chronic and superficial inflammation of colorectum. Chromoendoscopy has been informed as a method to improve evaluation of extension of UC. No reports on this issue have been published in Mexico to date. OBJECTIVE: To investigate usefulness of chromoendoscopy in determination of extension and severity of UC, as well as inter-observer variability. PATIENTS AND METHODS: Twenty five patients with diagnosis of UC were selected from March 2001 to January 2002 to enter this prospective study. Baron scale was used to evaluate UC endoscopic severity and was followed by randomization of patients to receive methylene blue 0.2% (14 cases) or indigo carmine 0.1% (11 cases) for chromoendoscopic assessment. Each case was presented for evaluation to five endoscopists with > 5 years experience in colonoscopy. Histopathologic report was considered gold standard. STATISTICAL ANALYSIS: Weighed Kappa coefficient for endoscopic-pathologic agreement among evaluators was used. RESULTS AND DISCUSSION: There was fair agreement among endoscopic and pathologic diagnoses of each observer with the two tinctures, particularly when using indigo carmine. Chromoendoscopy increased detection of areas affected by UC with minimal or silent activity. CONCLUSIONS: Chromoendoscopy with indigo carmine or methylene blue may increase endoscopic-pathologic agreement for assessment of severity of UC, thus being a helpful complementary technique in these patients.

Diferencias histológicas del tejido óseo alveolar mandibular asociados al envejecimiento / Histological differences of the mandibular alveolar bone tissue related to aging

OBJETIVO: se realizó un estudio descriptivo histológico con el que se buscaba observar los cambios histológicos del tejido óseo alveolar mandibular asociados al envejecimiento, como paso preliminar para estudios de tipo molecular, que permitan tener una mayor apropiación del conocimiento sobre el tema y así realizar pronóstico más congruentes con la capacidad de respuestas en tratamientos que involucren este tejido. METODOS: la población estuvo conformada por pacientes que asistieron a la clínica de cirugía de la facultad de odontología de Pontificia Universidad Javeriana. La muestra estuvo constituida por 30 pacientes de género masculino y femenino en un rango de 10 a 69 años. Fueron pacientes sanos sistemáticamente, sin lecciones óseas degenerativas de los maxilares, ni enfermedad periodontal, quienes se les realizaron procedimiento de exodoncia indicada en zona de premolares y molares inferiores. Se efectuó la toma de la muestra de hueso de 2-3 mm. Se realizaron coloraciones de hematoxilinaeosina y Von Kossa para su análisis en microscopio de luz, mediante el cual se observó, continuidad de la membrana, forma y tamaño de núcleo de osteoblastos, forma y tamaño de la células celularidad del hueso esponjoso y presencia do fosfato de calcio en el tejido.RESULTADOS: No se presentaron diferencias estadísticamente significativas en los grupos de edades estudiados (p=0.05).

Complicaciones nasofaríngeas de la conjutivitis folicular por chalmydia trachomatis. Una causa de la falta de respuesta al tratamiento / Nasopharingeal complications secundary to Clamydia trachomatis follicular conjunctivitis. A cause of therapeutic failure

Se realizó un estudio retrospectivo en 6 409 casos consecutivos en un lapso de enero de 1992 a febrero de 1997, se seleccionaron 183 frotis nasales y 271 faríngeos provenientes de 396 pacientes. Chlamydia trachomatis fue el agente etiológico en el 67.80 por ciento de los frotis nasales y 8.11 por ciento de las muestras faríngeas. La infección nasal es casi siempre secundaria a la infección ocular y a su vez es un factor de diseminación y de falta de respuesta adecuada al tratamiento, por lo que es indispensable identificar el problema y dar tratamiento simultáneo

Enfermo de 79 años de edad con disfagia alta, perdida de peso y lesiones cutaneas en miembros inferiores / 79-year old patient with upper dispplagia, weight loss aand and cutaneous lesions in the legs (clinical conference)

EES. masculino de 79 años de edad con antecedentes heredofamiliares irrelevantes y personales de tabaquismo leve y alcoholismo intenso durante su juventud. A los 59 años de edad presentó un episodio de hematemesis requiriendo hospitalización fuera de esta Institución, se ignora la causa pero se sabe que se le practica una biopsia hepática. Inicia su padecimiento 6 meses antes con edema en tobillos, cefalea y pérdida de peso. A lo que se agrega 3 meses después, disfalgia alta progresiva y lesiones eritematosas en tobillo izquierdo que en pocos días evoluciona a bula que al romperse deja una zona eritematosa con fondo necrótico. La lesión se "extiende" a pierna izquierda y posteriormente a la derecha. Dos semanas antes de su ingreso se agrega somnolencia y desorientación. En la exploración física se encontró un sujeto conciente pero desorientado en tiempo y espacio, muy adelgazado, mucosas secas e hipotrofica muscular generalizada. Se observó aumento de volumen en paladar blando el cual se "movía" poco al provocar el refejo nauseoso. Cuello sin patología aparente. En tórax los ruidos cardiaco se encontraron "arrítmicos" sin fenómenos agregados e hipoventilación pulmonar generalizada predominantemente en región subescapular izquierda. Abdomen sin visceromegalia o ascitis. En piernas (región pretibial) y 2§ 3§ y 4§ dedo de mano izquierda y 4§ dedo de mano derecha se aprecian bulas rodeadas de un halo eritematoso, algunas con esfacelo y cubiertas de secreción amarillenta fétida. Al tacto rectal se encontró una próstata crecida sin nodulaciones...