Dermatitis por Paederus. Acerca de tres casos / Paederus dermatitis. About three cases

Resumen La "dermatitis por Paederus", es una dermatitis vesicante secundaria al contacto con coleópteros de este género. Se describen más de 600 especies de Paederus, con predominio en áreas tropicales y subtropicales, varias de ellas se asocian a dermatitis. Al ser apretado o aplastado contra la piel, la hemolinfa que contiene paederina, lesiona la epidermis, por medio del bloqueo de la mitosis de células epiteliales basales y células suprabasales. Se exponen tres casos clínicos dermatológicos con lesiones características compatibles con "dermatitis por Paederus". Se realiza además una revisión bibliográfica sobre el tema, a fin de exponer los puntos más importantes de esta patología de gran interés médico y que representa en muchas ocasiones desafíos diagnósticos.

Summary "Paederus dermatitis" is a vesicant dermatitis secondary to contact with this beetle. There are more than 600 species of Paederus described, with a predominance in tropical and subtropical areas, some of these are associated with dermatitis. When they are pressed or crushed against the skin, releases secretions with pederin, that causes an injury in the epidermis, by mitosis blocking of basal and suprabasal epithelial cells. This article describes three dermatological clinical cases with charac-teristic lesions compatible with "Paederus dermatitis". In addition a bibliographic review is presented in order to expose the most important points of this medical interest pathology, that frequently represents diagnostic challenges.

Intoxicación severa por Nicotiana glauca (Palán Palán) con miocardio atontado / Severe poisoning by Nicotiana glauca (Palán Palán) with stunned myocardium

Resumen Nicotiana glauca también llamada Palán Palán, es un arbusto con hojas verdes azuladas y despulidas y una flor amarilla tubular pendulante que presenta alcaloides piridínicos, como nicotina, nornicotina, anatabina y anabastina (análogo estructural de la Nicotina). Se presenta el caso clínico de una paciente de 50 años con cuadro agudo de debilidad muscular generalizada que evoluciona con paro respiratorio, tras la ingesta accidental de una cantidad desconocida de hojas de Nicotiana glauca, cultivadas en una huerta hogareña mediante técnica de hidroponía y confundidas por su conviviente con espinaca. Presentó aumento de lactato y Troponina Ultra Sensible e Hipoquinesia Global de Ventrículo Izquierdo en el ecocardiograma, compatible con Aton tamiento Miocárdico (AM), que evolucionó favorablemente. Si bien hay pocos reportes, se han informado muertes de animales y humanos, tras la ingesta accidental de Nicotiana glauca. El inicio del cuadro es rápido, con patrón bifásico, con vómitos y estímulo simpático, seguido por bloqueo ganglionar y neuromuscular, pudiendo presentar paro respiratorio, shock, convulsiones y coma. El AM es una disfunción miocárdica prolongada con retorno gradual de la actividad contráctil, posterior a un episodio breve de isquemia grave, puede ser asintomático, pudiendo presentar alteraciones en el electrocardiograma, enzimas cardíacas o ecocardiograma. Generalmente presenta pronóstico favorable, pudiendo presentar insuficiencia cardíaca ante patologías concurrentes o aumento de requerimientos de oxígeno.

Abstract Nicotiana glauca is a shrub with bluish green leaves and a pendulous tubular yellow flower. It has pyridine alkaloids, such as nicotine, nornicotine, anatabine and anabastine (structural analog of Nicotine). We present the case of a 50 years old pa- tient with acute generalized muscle weakness that evolves to respiratory arrest, after accidentally ingesting an unknown quantity of Nicotiana glauca leaves, grown in a home vegetable garden, using a hydroponic technique and confused by her cohabiting with spinach. She presented increased lactate and Ultra Sensitive Troponin and Left Ventricular Global Hypokinesia in the echo- cardiogram, compatible with Myocardial Stunned, that it evolved favorably. There are few reports, animal and human deaths have been reported following accidental ingestion of Nicotiana glauca. The onset of the symptoms is early, with a biphasic pattern, with vomiting and sympathetic stimulation, followed by ganglionic and neuromuscular blockage and may present respiratory arrest, shock, seizures and coma. Myocardial Stunned is a prolonged myocardial dysfunction with gradual return of contractile activity after a brief episode of severe ischemia, it can be asymptomatic, and it can present alterations in the electrocardiogram, cardiac enzymes or echocardiogram. Generally presents a benign prognosis, being able to present heart failure with concurrent patholo- gies or increased requirements.

Variaciones de caracteres morfológicos dentro de la especie Bothrops alternatus / Morphological characters variations within the Bothrops alternatus species

Resumen El género Bothrops (yarará) es responsable de más del 95% de los accidentes por ofidios venenosos en Argentina. La mayoría de éstos son notificados en provincias del Nordeste y Noroeste. Bothrops alternatus, es la especie más frecuentementehallada, siendo el vipérido de gran talla más meridional del mundo y una de las especies de mayor importancia sanitaria en Argentina, pudiendo hallarse en relación a núcleos urbanos. Presentan en el dorso figuras arriñonadas características, que remedan atubos de teléfono o porotos unidos, completos o incompletos, hasta la forma fusionada. Presenta foseta loreal, órgano termore-ceptor ubicado entre el ojo y la fosa nasal. Su dentición es solenoglifa, dientes inoculadores huecos, con conducto cerrado, fijosa un hueso maxilar móvil. Si bien se describen variaciones entre animales, se considera una especie monotípica. Su identificaciónes importante dada la abundancia de especímenes y de hallazgos en regiones periurbanas.

Abstract The Bothrops genus is responsible for more than 95% of ophidian accidents in Argentina, most of these are reported in the Northeast and Northwest provinces. Bothrops alternatus, is the most frequent species of the genus Bothrops (yarará), themost southern large-scale viperid in the world and one of the most important species in Argentina, being able to be found in rela-tion to urban nucleus. Their characteristic features are kidney-like figures in the skin, that mimic phone tubes or beans, completeor incomplete, until the merged form. It presents a loreal pit, thermoreceptor organ located between the eye and the nostril. Itsdentition is solenoglyphous, hollow inoculating teeth, with closed duct, fixed to a mobile maxillary bone. Although variationsbetween animals are described, it is considered a monotypic species. The identification of this snake is important due their abun-dance in around urban regions and its frequency of finding.

Control y prevención de los accidentes causados por Tityus trivittatus (Scorpiones: Buthidae) / Control and prevention of accidents caused by Tityus trivittatus (Scorpiones: Buthidae)

Resumen Las picaduras por alacranes pueden producir cuadros de intoxicación aguda y conducir a la muerte por falla cardíaca y distrés respiratorio, siendo la población pediátrica la de mayor riesgo, tanto en Argentina como en el resto del mundo. Muchasde las especies de escorpiones en el mundo son sinantrópicas, y en Argentina, las que se han relacionado con muertes, comoTityus trivittatus y Tityus confluens, poseen esas características. La sinantropía, aumenta la posibilidad de contacto humano -escorpión y por lo tanto la ocurrencia de accidentes, por lo que las medidas de prevención en este caso, deben tomarse no soloconductualmente sino ambientalmente para evitar ese contacto. Las características biológicas de los escorpiones del géneroTityus dificultan las labores de prevención. Muchas son las herramientas para disminuir el contacto con los escorpiones y de esamanera prevenir los accidentes como los controles químicos, biológicos y ambientales, así como la búsqueda y eliminación deescorpiones. Sin embargo, no todas son efectivas si no son aplicadas racionalmente y si no son combinadas. En ocasiones lamala planificación o uso de las diferentes medidas para el combate de escorpiones pueden ser contraproducentes y no solo serinefectivas sino aumentar la probabilidad de ocurrencia de accidentes. En esta revisión se exponen los diferentes métodos deprevención del escorpionismo, con especial referencia a las especies de Tityus de Argentina.

Abstract Scorpion stings may produce acute envenoming and lead to death from heart failure and respiratory distress, being the pediatric population that with the highest risk of severe envenomation and death, in Argentina as in the rest of the world. Manyof the scorpion species in the world are synanthropic, including Tityus trivittatus and Tityus confluens, which are responsible forhuman deaths in Argentina. Synanthropy increases the possibility of human-scorpion contact and therefore the occurrence ofaccidents, so preventive measures to avoid the contact must be taken not only behaviorally but environmentally. The biologi-cal characteristics of scorpions of the genus Tityus make prevention of the contact with humans rather difficult. There are manychemical, biological and environmental tools to reduce the possibility of contact between humans and scorpions. However, notall these measures are effective if they are not rationally applied and if these are not combined. Sometimes the poor planningor use of different measures to control scorpions' population can be counterproductive and not only ineffective, increasing theprobability of accidents. In this review, we discuss the different methods of prevention and combat of scorpionism, with specialreference to the prevention of accidents with Tityus species from Argentina.

Excretion-secretion products and proteases from live Sporothrix schenckii yeast phase: immunological detection and cleavage of human IgG / Produtos da excreção-secreção e proteases da fase leveduriforme do Sporothrix schenckii: detecção imunológica e clivagem de IgG humana

Antigenic preparations from Sporothrix schenckii usually involve materials from mixed cultures of yeast and mycelia presenting cross-reactions with other deep mycoses. We have standardized pure yeast phase with high viability of the cells suitable to obtain specific excretion-secretion products without somatic contaminations. These excretion-secretion products were highly immunogenic and did not produce noticeable cross-reactions in either double immunodiffusion or Western blot. The antigenic preparation consists mainly of proteins with molecular weights between 40 and 70 kDa, some of them with proteolytic activity in mild acidic conditions. We also observed cathepsin-like activity at two days of culture and chymotrypsin-like activity at four days of culture consistent with the change in concentration of different secreted proteins. The proteases were able to cleave different subclasses of human IgG suggesting a sequential production of antigens and molecules that could interact and interfere with the immune response of the host.

As preparações antigênicas de Sporothrix schenckii provêm geralmente de cultivos mistos de leveduras e micélios e apresentam reações cruzadas com outras micoses profundas. Foi padronizada a obtenção da fase leveduriforme pura, com alto índice de células viáveis, o que permite, por sua vez, obter produtos específicos da excreção-secreção sem contaminantes somáticos. Estes produtos da excreção-secreção são altamente imunogênicos, e não apresentam reações cruzadas visíveis em dupla difusão e sem Western blot. O preparado antigênico consiste principalmente em proteínas com peso molecular entre 40 e 70 kDa, sendo que algumas apresentam atividade proteolítica em meios levemente ácidos. Foi observada atividade do tipo catepsina em produtos da excreção-secreção obtidos a partir de leveduras de dois dias de cultivo, e atividade do tipo quimiotripsina aos quatro dias de cultivo, consistente com a mudança de concentração de proteínas secretadas. As proteases puderam clivar diferentes subclasses de IgG humanas, o que sugere uma produção seqüencial de antígenos e moléculas que podem interagir com a resposta imune do hospedeiro.