Um eqüino de nove anos de idade apresentou ausência de ar expirado e secreção serossanguinolenta na narina direita, associado a ruído respiratório. Os exames endoscópico e radiológico mostraram uma formação de aproximadamente seis centímetros de diâmetro recoberta por mucosa amarelada, que obstruía a cavidade nasal direita e insinuava-se para a cavidade nasal esquerda. Tal massa foi ressecada por meio de sinusotomia frontal direita. O exame histológico e a cultura revelaram lesão granulomatosa causada por fungos. O tratamento pós-operatório compreendeu associação de antibiótico e antiinflamatório, assim como de lavagens com água destilada e chá de camomila.

A 9-year-old horse presented serosanguineous nasal discharge, absence of breath out through the right nostril, and respiratory noise. Endoscopic and radiographic exams revealed a six centimeter diameter mass, covered by yellowish mucosa, which was obstructing the entire right nasal cavity and part of the left one. The mass was excised through a right frontal sinusotomy. The microscopic exam and the culture revealed a fungic granulomatous rhinitis. Antibiotic and anti-inflammatory drugs were postoperatively administered; moreover, camomile tea and distilled water were flushed in a drain placed above the bone flap.

RESUMO Esta pesquisa visou estabelecer valores de referência para a interpretação da reação tuberculínica em ovinos experimentalmente inoculados com cepas padrões de Mycobacterium bovis AN5 e Mycobacterium avium D4, além de avaliar possíveis reações clínicas provocadas pela resposta imuno-alérgica intradérmica à tuberculina. Utilizou-se 30 ovinos, distribuídos por 3 grupos de 10 animais cada, a saber: A sensibilizados M. avium; B sensibilizados M. bovis e C – não sensibilizado (controle) – que receberam injeção de solução fisiológica. Após 45 dias da sensibilização, realizou-se o Teste Cervical Comparativo (TCC) com reação medida pela variação da espessura da pele com cutímetro de mola, nos seguintes momentos: antes da aplicação das tuberculinas (PPDs -derivado protéico purificado), 12h, 24h, 48h, 72h e 96h após a aplicação. Em relação à reação ao PPD bovino, no Teste Cervical Simples (TCS), lido às 72h (± 6 horas) pós-tuberculinização (p. t.), considerou-se uma reação positiva, quando o aumento da espessura da pele foi igual ou maior que 2,40 mm; como inconclusiva, com aumento entre 1,00 e 2,40 mm, e como reação negativa, aumentos da espessura da pele inferiores a 1 mm. A análise dos resultados da leitura do TCC, realizada às 72h p. t., permitiu concluir que o animal poderá ser considerado com resposta: positiva, quando a reação ao PPD bovino superar aquela ao aviário em pelo menos 2 mm; inconclusiva, quando a reação ao PPD bovino for maior que aquela ao aviário, com diferença entre 1 e 1,90 mm, e negativa quando a reação bovina for menor que a aviária ou maior em até 0,90 mm. Estes valores obtidos para o TCS e TCC são propostos como padrão de interpretação desses testes em ovinos.

ABSTRACT This study aimed to establish the reference values for the interpretation of the skin test in sheep experimentally inoculated with standard strains of Mycobacterium bovis AN5 and Mycobacterium avium D4, and evaluated the clinical manifestations induced by the intradermic immune-allergic response to tuberculin. Thirty healthy sheep were separated in three groups: A) sensitized with M. avium, n = 10; B) sensitized with M. bovis, n = 10; and C) control, n = 10, which were injected with saline solution. After 45 days of inoculation, the Comparative Cervical Test (CCT) was evaluated by the variation of dermal thickness measured by skinfold calipers carried out at the following moments: before the administration of tuberculin (PPD – purified protein derivative) and at 12, 48, 72 and 96 hours after PPD inoculation. In regard to the bovine PPD, the Single Cervical Test (SCT), observed at 72 hours (± 6 hours) post-tuberculinization (p.t.) the response was considered as: positive, when skinfold thickness was equal or greater than 2.40 mm; inconclusive, when skinfold thickness was between 1 and 2.40 mm; and negative, when skinfold thickness was lower than 1 mm. Analyses of the results of the CCT performed at 72 hr p.t.

Caracterizaram-se a linhagem e o grau de diferenciação das células neoplásicas no estudo histopatológico e ultraestrutural da leucose mielóide. Histologicamente as células neoplásicas apresentaram pleomorfismo, núcleos ovais, nucléolos proeminentes, cromatina distribuída de maneira irregular, figuras de mitose atípicas e moderada quantidade de citoplasma contendo granulações eosinofílicas esféricas. Essas características indicam a linhagem mielóide. Ultraestruturalmente evidenciaram-se células com núcleo oval, volumoso, eletrodenso, com predomínio de eucromatina e citoplasma com numerosos grânulos esféricos, eletrodensos e homogêneos, indicando mielócitos com diferenciação para eosinófilos. Constatou-se também a presença de partículas virais tipo-C no espaço intercelular dos túbulos renais, no interior de vesículas intracitoplasmáticas dos mielócitos imaturos presentes na medula óssea e ovário, e PCR positivo para ALV-J.

An ultrastructural and histological study was performed to determine the degree of differentiation of the neoplastic cells. The histological study revealed neoplastic cells with pleomorphism, oval nuclei, prominent nucleoli, irregularly distributed chromatin, atypical mitotic figures and moderate amount of cytoplasm containing spherical eosinophilic granulations, typical features of the myeloid lineage. Ultrastructurally, there were cells with an electron-dense, oval and voluminous nucleus, with predominant euchromatin and cytoplasm containing many spherical, electron-dense and homogeneous granules, indicative of myelocytes with differentiation to eosinophils. Type-C viral particles were also seen in the intercellular space of renal tubules and inside the intracytoplasmic vesicles of immature myelocytes in the bone marrow and ovary. PCR was positive to ALV-J.

Schwann cell disturbance followed by segmental demyelination in the peripheral nervous system occurs in diabetic patients. Since Schwann cell and oligodendrocyte remyelination in the central nervous system is a well-known event in the ethidium bromide (EB) demyelinating model, the aim of this investigation was to determine the behavior of both cell types after local EB injection into the brainstem of streptozotocin diabetic rats. Adult male Wistar rats received a single intravenous injection of streptozotocin (50 mg/kg) and were submitted 10 days later to a single injection of 10 µL 0.1% (w/v) EB or 0.9% saline solution into the cisterna pontis. Ten microliters of 0.1% EB was also injected into non-diabetic rats. The animals were anesthetized and perfused through the heart 7 to 31 days after EB or saline injection and brainstem sections were collected and processed for light and transmission electron microscopy. The final balance of myelin repair in diabetic and non-diabetic rats at 31 days was compared using a semi-quantitative method. Diabetic rats presented delayed macrophage activity and lesser remyelination compared to non-diabetic rats. Although oligodendrocytes were the major remyelinating cells in the brainstem, Schwann cells invaded EB-induced lesions, first appearing at 11 days in non-diabetic rats and by 15 days in diabetic rats. Results indicate that short-term streptozotocin-induced diabetes hindered both oligodendrocyte and Schwann cell remyelination (mean remyelination scores of 2.57 ± 0.77 for oligodendrocytes and 0.67 ± 0.5 for Schwann cells) compared to non-diabetic rats (3.27 ± 0.85 and 1.38 ± 0.81, respectively).

Complement-depleted and -non-depleted BALB/c mice were inoculated with Leishmania (Leishmania) amazonensis promastigotes into the hind footpad to study the role of the complement system in cutaneous leishmaniasis. Total serum complement activity was measured by hemolytic assay and C3 fragment deposit at the inoculation site was determined by direct immunofluorescence in the early period of infection, i.e., at 3, 24, 48 h and 7 days post-infection. The inflammatory reaction and the parasite burden were evaluated in the skin lesion at 7 and 30 days post-infection. Total serum complement activity decreased in the early phase of infection, from 3 to 24 h, in non-depleted mice compared to non-infected and non-depleted mice. C3 fragment deposit at the site of parasite inoculation was present throughout the period of infection in non-depleted mice. In contrast, no C3 fragment deposit was observed at the inoculation site in complement-depleted mice. Complement-depleted mice showed a significant decrease in the inflammatory response and a significant increase in the number of parasites (70.0 ± 5.3 vs 5.3 ± 1.5) at 7 days of infection (P < 0.05). A higher number of parasites were also present at 30 days of infection at the inoculation site of complement-depleted mice (78.5 ± 24.9 vs 6.3 ± 5.7). These experiments indicate that complement has an important role at the beginning of experimental cutaneous leishmaniasis caused by L. (L.) amazonensis by controlling the number of parasites in the lesion.

O presente estudo teve por objetivo investigar as alterações ultraestruturais da mucosa intestinal e do tecido linfóide associado na inoculação experimental de Cryptosporidium sp. Doze leitões foram inoculados experimentalmente por via oral com 1×10(6) oocistos e sacrificados 3, 6, 9 e 12 dias depois. Ao exame ultraestrutural de células intestinais observou-se espessamento e irregularidade de microvilosidades, citoplasma vacuolizado e com protrusões, edema mitocondrial, hipertrofia de organelas citoplasmáticas e do núcleo. Nas placas de Peyer observou-se ocasionalmente mitose de células linfóides, verificando-se maior número de células blásticas.

The aim of this work was to determine ultrastructural changes on the intestinal mucosa and associated lymphoid tissues after an experimental infection with Cryptosporidium sp. Twelve piglets dosed orally with 1×10(6) oocysts were slaughtered on days 3, 6, 9 and 12 after inoculation. The ultrastructural lesions in the intestinal cells were irregular with thickened microvilli, cytoplasmic protrusions and vacuolation, swollen mitochondria, hypertrophic organelles and nuclei. The lymphocytes of the Peyer’s patches occasionally were mitotic with a larger number of lymphoblasts in the inoculated animals.

In order to study the role of natural killer (NK) cells during the early period of Leishmania infection, BALB/c mice were selectively and permanently depleted of NK cells by injection with 90Sr and subsequently infected with Leishmania (Leishmania) amazonensis (HSJD-1 strain). 90Sr is known to selectively deplete NK cells, leaving an intact T- and B-cell compartment and preserving the ability to produce both interferon alpha and IL-2. This method of depletion has advantages when compared with depletion using anti-NK cell monoclonal antibodies because the effect is permanent and neither activates complement nor provokes massive cell death. In the present study, after one month of treatment with 90Sr, the depletion of NK cells was shown by a more than ten-fold reduction in the cytotoxic activity of these cells: 2 x 106 spleen cells from NK-depleted animals were required to reach the same specific lysis of target cells effected by 0.15 x 106 spleen cells from normal control animals. The histopathology of the skin lesion at 7 days after Leishmania infection showed more parasites in the NK cell-depleted group. This observation further strengthens a direct role of NK cells during the early period of Leishmania infection.