ABSTRACT Purpose: To evaluate macro/microscopic viability of the upper pole (UP) in rats after 80 days of subtotal splenectomy preserving the upper pole (SSPUP). Methods: Twenty-five male Wistar rats were submitted to SSPUP. After 80 days, the rats were euthanized, and the remaining UP was evaluated macroscopically regarding appearance, color, consistency, length, width, thickness, and presence of fibrosis/necrosis; and microscopically regarding presence of red and white pulp, fibrosis/necrosis. Results: Two rats died during surgery and were removed from the statistical analysis. There was statistically significant increase in length and width between the pre and postoperative in the experimental group, with no significant difference in thickness. In the manipulation group, the macroscopic appearance of the spleen was normal in pre and postoperative, with viability preserved. In the experimental group, two UP of the spleen were not found during the second surgery. Macroscopically, it was observed absence of fibrosis and necrosis in all cases. Microscopically, the white and red pulp were intact in both groups. Two spleens of rats in the manipulation group presented areas with fibrosis and necrosis focus, which were not enough to be considered inviable. Conclusions: The UP of the spleen remained viable in 91.3% of the cases.

Abstract Purpose To evaluate the viability of the upper (UP) and lower pole (LP) of the spleen from a macro and microscopic point of view, after subtotal splenectomy with preservation (SSP) of the UP and the LP. Methods Seventeen male Wistar rats, two months old, were submitted to SSPUP and SSPLP and 5 to simulated operation (SG). After 80 days, the rats were euthanized, and the remaining LP and UP and intact spleens were evaluated macroscopically and microscopically. Results Two rats died during the operation. Macroscopic analysis showed that in 15 LP, one of them was not viable and in 15 UP and in 5 spleens in the SG, all were viable. In the statistical analysis, there was no difference in relation to viability. The LP and UP analyzed showed variation. As for the length, the UP increased significantly; however, in relation to the width, there was a significant increase in the LP in relation to the UP. In addition, the weight of the UP was significantly greater than that of the LP. Microscopic analysis attested viability of the splenic remnants. Conclusion There was no significant difference regarding the viability of UP and LP, in macroscopy and microscopy.

<p>Os schwannomas são tumores benignos, geralmente solitários, encapsulados e de crescimento lento, que têm sua origem nas células de Schwann neoplásicas diferenciadas, com desenvolvimento habitual extramedular intradural relacionado com as raízes nervosas. O schwannoma melanocítico é uma variante dessas neoplasias cuja localização em quase um terço dos casos está na raiz nervosa posterior, com apresentação clínica inespecífica. A ressonância magnética é o exame de imagem mais utilizado no diagnóstico, revelando imagens hiperintensas em T1 e hipointensas em T2. A confirmação diagnóstica é obtida através do estudo histológico e imuno-histoquímico, em que se observa intensa pigmentação citoplasmática. Existem dois tipos distintos de schwannomas melanocíticos: o esporádico e o psamomatoso, este último relacionado ao chamado complexo de Carney, uma forma de neoplasia endócrina múltipla de caráter familiar. Na literatura, encontramos poucos casos dessas neoplasias, sendo a maior série composta por cinco casos. Assim, o objetivo deste trabalho é relatar um raro caso de schwannoma melanocítico da coluna lombar do tipo esporádico de localização extramedular. Apresentamos ainda uma breve revisão de literatura contendo as principais características do tumor, incluindo suas diferentes formas, diagnósticos diferenciais, dados do estudo histológico e imuno-histoquímico, bem como a abordagem atualmente preconizada, a fim de colaborar para o melhor entendimento desta neoplasia.</p>

<p>Schwannomas are benign tumors, usually solitary, encapsulated, slow-growing, which have their origin in differentiated neoplastic Schwann cells with extramedullary intradural usual development related to nerve roots. The melanotic schwannoma is a variant of these tumors whose location in almost one third of cases is on the posterior spinal nerve root, with a nonspecific clinical presentation. Magnetic resonance imaging is the most widely used test for the diagnosis, revealing hyperintense T1-weighted sequences and hypointense T2-weighted sequences. Diagnostic confirmation is obtained by histological and immunohistochemical studies, in which there is intense cytoplasmatic pigmentation. There are two distinct types of melanotic schwannomas: sporadic and psammomatous, the latter related to the called Carney complex, a form of multiple endocrine neoplasm with familiar character. In literature we found few cases of these neoplasms, the largest series consisting of five cases. The objective of this study is to report a rare case of melanotic schwannoma of the lumbar spine of the sporadic type of extramedullary location. We also present a brief review of the literature containing the main characteristics of the tumor, including its different forms, differential diagnoses, data from histological and immunohistochemical studies as well as the currently recommended approach in order to contribute to a better understanding of this neoplasm.</p>

<p>Los schwannomas son tumores benignos, generalmente solitarios, encapsulados y de crecimiento lento, que tienen su origen en las células de Schwann neoplásicas diferenciadas con desarrollo habitual intradural extramedular relacionado con las raíces nerviosas. El schwannoma melanótico es una variante de estos tumores cuya localización en casi un tercio de los casos se encuentra en la raíz nerviosa posterior, con presentación clínica no específica. La resonancia magnética es el examen más ampliamente utilizado en el diagnóstico, con hiperintensidad en secuencias T1 e hiposeñal en T2. La confirmación del diagnóstico se obtiene por el estudio histológico e inmunohistoquímico, en el que existe una intensa pigmentación citoplásmica. Hay dos tipos distintos de schwannoma melanótico: el esporádico y el psamomatoso, este último relacionado con el llamado complejo de Carney, una forma de neoplasia endocrina múltiple de carácter familiar. En la literatura encontramos pocos casos de estos tumores, la serie más grande consta de cinco casos. El objetivo de este trabajo es presentar un caso raro de schwannoma melanótico lumbar del tipo esporádico y de localización extramedular. También presentamos una breve revisión de la literatura que contiene las principales características del tumor, incluyendo sus diferentes formas, los diagnósticos diferenciales, los datos del estudio histológico e inmunohistoquímico, así como el tratamiento recomendado actualmente, a fin de contribuir a una mejor comprensión de esta neoplasia.</p>

PURPOSE: To analyze PCNA immunoexpression on the inferior pole of the spleen of splenectomized rats submitted to hyperbaric oxygenation (HBO). METHODS: Were analyzed fragments of the inferior pole of the spleen of 20 male Wistar rats submitted to splenectomy with preservation of the inferior pole. The rats were divided in two groups: group A (n=10) without HBO and group B (n=10) submitted to HBO at 2, 5 atmospheres per 120 minutes, twice a day for three days and once a day for seven days. The groups were then subdivided in four subgroups: A15 (n=5), with euthanasia on the 15th day; A45 (n=5), with euthanasia on the 45th day; B15 (n=5) with euthanasia on the 15th day and B45 with euthanasia on the 45th day. Respectively on these days, fragments of the inferior pole of the spleen of all animals were collected and analyzed with the immunohistochemistry technique in order to evaluate PCNA expression. RESULTS: There was an expressive increase in PCNA immunoreactivity in the group B. The 45 day postoperative period resulted in a higher level of positivity than the 15 day postoperative period (p<0.01). CONCLUSION: The quantitative analysis of proliferating cell nuclear antigen positive suggests that hyperbaric oxygenation increases cellular proliferation, contributing to splenic regeneration.

O Edema Agudo Hemorrágico da Infância é uma vasculite leucocitoclástica pouco frequente, que ocorre, quase exclusivamente, em crianças entre 4 meses e 2 anos de idade. Caracteriza-se, clinicamente, pela tríade febre, lesões purpúricas na face, pavilhões auriculares e extremidades e edema. Embora os achados cutâneos sejam dramáticos e de surgimento rápido, o prognóstico é favorável, com resolução espontânea dentro de 1 a 3 semanas. Descrevem-se três casos cujos achados clínicos e histopatológicos são característicos de edema agudo hemorrágico da infância.

Acute Hemorrhagic Edema of Infancy is an infrequent leukocytoclastic vasculitis which occurs almost exclusively in children between 4 months and 2 years of age. It is clinically characterized by the triad fever, purpuric lesions on the face, auricular pinna and extremities, and edema. Although the cutaneous findings are dramatic and of rapid onset, the prognosis is favorable, with spontaneous resolution within 1 to 3 weeks. Three cases are described in which clinical and histopathological findings are characteristic of acute hemorrhagic edema of infancy.

A histiocitose de células de Langerhans é proliferação clonal de células fenotipicamente semelhantes às células de Langerhans. Anteriormente denominada Letterer-Siwe, é a forma mais comum e mais grave dessa enfermidade, acometendo sobretudo crianças até os dois anos de idade. São apresentados dois casos dessa rara doença, diagnosticados após parecer dermatológico, destacando-se seus aspectos mais característicos.

Langerhans cell histiocytosis is defined as a clonal proliferation of Langerhans phenotypic-like cells. Letterer-Siwe disease is the most common and serious of these entities, affecting mainly infants up to two years of age. We present two cases of this rare disease, diagnosed after dermatological examination, highligthing its typical aspects.