Quiste epidermoide en conducto auditivo externo: reporte de caso / Epidermoid cysts of the external auditory canal: case report

Resumen El quiste epidérmico es una lesión benigna y común de la piel. Se desarrolla por un bloqueo de la unidad pilosebácea, con la consecuente proliferación de células epiteliales y secuestro de queratina. El 7% se desarrollan en cabeza y cuello, sin embargo, son infrecuentes en canal auditivo externo. Su patrón de crecimiento es lento y progresivo durante años, siendo asintomáticos. Al aumentar de tamaño causan sintomatología variable, acorde a su localización; en el canal auditivo tienen un comportamiento obstructivo que genera síntomas como otalgia e hipoacusia. Se presenta caso de una paciente de 69 años, con acúfeno e hipoacusia progresiva derecha. Durante la otoscopia se observó una neoformación obstructiva del 100% de la luz del conducto. Se realizaron estudios de imagen que reportaron tumoración de características quísticas de conducto auditivo derecho, bien circunscrita, sin erosión ósea. Para el diagnóstico definitivo, se realizó resección quirúrgica y biopsia reportando quiste epidérmico. Durante el seguimiento posoperatorio sin hallazgos de recidiva.

Abstract The epidermal cyst is a common and benign lesion of the skin. It develops due to a blockage of the pilosebaceous unit, with the consequent proliferation of epithelial cells and keratin sequestration. Seven percent develop in the head and neck; however, they are infrequent in the external auditory canal. Its growth pattern is slow and progressive over the years, being asymptomatic. As they increase in size, they cause variable symptoms, according to their location. In the ear canal they have an obstructive behavior that generates symptoms such as earache and hearing loss. A case of a 69-year-old female with tinnitus and progressive right hearing loss is presented. At otoscopy, a 100% obstructive neoformation of the canal lumen was observed. Imaging studies showed a well circumscribed, cystic tumor of the right ear canal, without bone erosion. For the definitive diagnosis, a resection and biopsy were performed, reporting an epidermal cyst. During follow up there was no recurrence of tumor.

Partial purification of tightly bound mitochondrial hexokinase from maize (Zea mays L) root membranes

In mammals, hexokinase (HK) is strategically located at the outer membrane of mitochondria bound to the porin protein. The mitochondrial HK is a crucial modulator of apoptosis and reactive oxygen species generation. In plants, these properties related to HK are unknown. In order to better understand the physiological role of non-cytosolic hexokinase (NC-HK) in plants, we developed a purification strategy here described. Crude extract of 400 g of maize roots (230 mg protein) contained a specific activity of 0.042 æmol G6P min-1 mg PTN-1. After solubilization with detergent two fractions were obtained by DEAE column chromatography, NC-HK 1 (specific activity = 3.6 æmol G6P min-1 mg PTN-1 and protein recovered = 0.7 mg) and NC-HK 2. A major purification (yield = 500-fold) was obtained after passage of NC-HK 1 through the hydrophobic phenyl-Sepharose column. The total amount of protein and activity recovered were 0.04 and 18 percent, respectively. The NC-HK 1 binds to the hydrophobic phenyl-Sepharose matrix, as observed for rat brain HK. Mild chymotrypsin digestion did not affect adsorption of NC-HK 1 to the hydrophobic column as it does for rat HK I. In contrast to mammal mitochondrial HK, glucose-6-phosphate, clotrimazole or thiopental did not dissociate NC-HK from maize (Zea mays) or rice (Oryza sativa) mitochondrial membranes. These data show that the interaction between maize or rice NC-HK to mitochondria differs from that reported in mammals, where the mitochondrial enzyme can be displaced by modulators or pharmacological agents known to interfere with the enzyme binding properties with the mitochondrial porin protein.

Tratamento das feridas anfractuosas e ou infectadas. / Treatment of anfractous and or infectious wounds

Foram estudados 31 pacientes com feridas anfractuosas e/ou contaminadas, bem como com ulceras por pressao, aos quais se aplicou um composto de enzimas proteoliticas, associado a um antimicrobiano em forma topica, na frequencia de uma a duas vezes ao dia. Foram adotadas medidas gerais de apoio como repouso relativo, asseio local e geral e, em alguns casos, procedimentos cirurgicos complementares. Os resultados foram tabulados quanto a idade, sexo, diagnostico e parametros clinicos evolutivos. Foram obtidos resultados favoraveis em todos os casos e na grande maioria dentro das duas primeiras semanas de tratamento