Alterações hematológicas em cães e gatos sob estresse

The leukocyte count interpretation on the blood helps on understanding about the possible dysfunction showed by the animal. In general, an abnormal leukogram allows the identification of pathological process. A lot of events lead to an increase in the number of neutrophils, among then, inflammatory process, infection and stress. Dependent on the stress mediator that the animal is submited, the leukocyte alteration will be different. Is important to know how the stress acts on the animal organism, changing the hematological parameters, in order to avoid mistakes on diseases‟ diagnosis. It‟s known that after a stress situation, it‟s expected that stress leukogram appears on the hemogram of the animal. However there are different kinds of stress with different responses. It‟s believed that when the animal is under an acute stress situation, a clinical picture of physiologic leukocytosis occurs which is mediated by the epinephrine. This is characterized by neutrophilia, lymphocytosis, monocytosis and eosinofilia. The physiologic leukocytosis is a transient alteration in the leukogram that occurs within minutes of the stimulus and due to fleeting effect of catecolamines it resolves within 20 to 30 minutes. However, if the animal is under chronicle stress, as solitude, it „s expected to find the stress leukogram on the leukogram, that can be noted especially in dogs. The stress leukogram is characterized by leukocytosis, neutrophilia, lymphopenia, monocytosis and eosinopenia. This kind of stress is induced by the glucocorticoids. It´s important to understand that stress leukogram takes time to occur. The variation on time depends on the animal species, although, in general, the glucocorticoides have a peak effects among 4 to 8 hours, which can last from 24 hours to 2 or 3 days

Prostaglandina E2 em cães portadores de linfoma multicêntrico submetidos ao protocolo quimioterápico de Madison-Wisconsin associado ou não a um inibidor de COX-2

Pós-graduação em Medicina Veterinária - FCAV

Spleenic Lymphoma and Hemoperitoneum in Jersey Bull: Clinical and Pathological Aspects

Lymphoma is the most prevalent neoplasia in dairy cattle. The etiology can be viral in animals affected by bovine leukemia virus (BLV) or be classified as primary. Lymphoma can affect several organs and according to the system involved, the clinical signs could manifest themselves in different ways. These tumors can be classified through macroscopic characteristics, histology and immunostaining. This classification can be used to predict prognosis and response to therapy. The aim of this case report was to immunostain and classify the tumor, for which anti-CD4, anti-CD8, anti-CD79 and anti-CD3 markers were used in addition to histopathological findings, in order to classify the tumor. The tumor was positive only for anti-CD3 marker, indicating that it is a tumor of young cells and, in association with histopathology and hematological data, it can be concluded that spleen neoplasia is lymphocytic lymphoma originated from a lymphocytic leukemia.

Estudo do efeito modulador do macrolídeo tilosina na reação inflamatória aguda de tilápias do Nilo (Oreochromis niloticus), vacinadas e desafiadas com Streptococcus agalactiae

Pós-graduação em Medicina Veterinária - FCAV

Hematological alterations during experimental canine infection by Trypanosoma cruzi

To confirm that Beagle dogs are a good experimental model for Chagas disease, we evaluated hematological alterations during the acute and chronic phases in Beagle dogs infected with the Y, Berenice-78 (Be-78) and ABC strains of Trypanosoma cruzi, correlating clinical signs with the parasitemia curve. We demonstrate that the acute phase of infection was marked by lethargy and loss of appetite. Simultaneously, we observed anemia, leukocytosis and lymphocytosis. Also,we describe hematological alterations and clinical signs that were positively correlated with the parasitemia during the experimental infection with the three strains of T cruzi, and demonstrate that experimental infection of Beagle is a trustworthy model for Chagas disease.

Intracellular Reactive Oxygen Species Production by Polymorphonuclear Leukocytes in Bovine Leukemia Virus-Infected Dairy Cows

The present study assesses the oxidative burst activity from polymorphonuclear leukocytes (PMNLs) from bovine leukemia virus (BLV)-infected cows. Fifteen clinically healthy cows were divided into serologically positive cows without any hematological alteration, serologically positive animals with persistent lymphocytosis (PL) and healthy serologically negative cows. The oxidative burst activity from the PMNLs was evaluated by now cytometry using 2',7'-dichlorofluorescein diacetate as a probe. PMNLs from each cow were incubated with heat-killed Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) to stimulate oxidative burst activity. The results of the present work showed no significant difference in the oxidative burst activity without any stimulus and elicited by S. caucus. Conversely, a decrease in the oxidative burst index induced by E. coli in PMNLs was observed in BLV-infected cows.

Quantification of B cells and T lymphocyte subsets in bovine leukemia virus infected dairy cows

The aim of the present trial was to determine the frequencies and absolute number of B and T lymphocytes subpopulations in bovine leukemia virus (BLV)-infected dairy cows with distinct lymphocyte profile known as non-leukemic (AL) and persistent lymphocytosis (PL). Thus, 15 animals were selected and divided uniformly in three groups (negative, AL, PL). The BLV infection was detected by agar gel immunodiffusion and enzyme-linked immunosorbent-assay. The lymphocytes subsets were evaluated using monoclonal antibodies by flow cytometry. The results of the present study pointed out to an increase in B lymphocytes, and also an augment in CD5(+) and CD11b(+) cells in animals showing PL. Consequently, it can be observed a decrease in the percentage of T cells subsets in these animals. Conversely, no significant alterations in the absolute number of the T lymphocytes, T CD4(+) cells and T CD8(+) lymphocytes were found in BLV-infected dairy cows with PL. Therefore, the correlation between the absolute numbers of B- and T cell subsets in the peripheral blood applied to each group showed a significant and positive strong correlation between numbers of B cells and T cells or T CD8(+) cells in the PL animals, although the same cannot be predicted for T CD4(+) lymphocytes. No such correlation was encountered for the AL and negative-control animals.

The Th17 pathway in cystic fibrosis lung disease

Cystic fibrosis (CF) is characterized by bronchoalveolar neutrophilia and submucosal lymphocytosis. We hypothesized that Th17 lymphocytes are part of this submucosal infiltrate.

Abnormal development of secondary lymphoid tissues in lymphotoxin β-deficient mice

The tumor necrosis factor (TNF) family cytokines lymphotoxin (LT) α and LTβ form heterotrimers that are expressed on the surface of activated lymphocytes and natural killer cells; LTα homotrimers can be secreted as well. Mice with a disrupted LTα gene lack lymph nodes (LN), Peyer’s patches (PP), and follicular dendritic cell (FDC) networks and reveal profound defects of the splenic architecture. However, it is unclear which of these abnormalities is the result of the absence in LTα homotrimers or LTαβ heterotrimers. To distinguish between these two possibilities, a mouse strain deficient in LTβ was created employing Cre/loxP-mediated gene targeting. Mice deficient in LTβ reveal severe defects in organogenesis of the lymphoid system similar to those of LTα−/− mice, except that mesenteric and cervical LN are present in most LTβ-deficient mice. Both LTβ- and LTα-deficient mice show significant lymphocytosis in the circulation and peritoneal cavity and lymphocytic infiltrations in lungs and liver. After immunization, PNA-positive B cell clusters were detected in the splenic white pulp of LTβ-deficient mice, but FDC networks were severely underdeveloped. Collectively, these results indicate that LTα can signal independently from LTβ in the formation of PNA-positive foci in the spleen, and especially in the development of mesenteric and cervical LN.

Enhanced and accelerated lymphoproliferation in Fas-null mice.

Fas is a 45-kDa membrane protein that transduces an apoptotic signal. The mouse lymphoproliferation (lpr) mutation is a leaky mutation of Fas. In this study, we examined lymphocyte development in Fas-null mice generated by gene targeting. The Fas-/- mice progressively accumulated abnormal T cells (Thy1+, B220+, CD4-, and CD8-) and developed lymphadenopathy and splenomegaly, which were much more accelerated and pronounced than those in lpr mice. In addition, the Fas-null mice showed lymphocytosis, accompanied by lymphocytic infiltration in the lungs and liver. The number of apparently normal B cells also increased, and large amounts of immunoglobulins, including anti-DNA antibodies, were produced. Thymic clonal deletion, assessed by deletion of T cells reactive to mouse endogenous superantigens, was apparently normal in the Fas-/- mice, whereas the peripheral clonal deletion of mature T cells against a bacterial superantigen was impaired. These results suggested that Fas plays a decisive role in peripheral clonal deletion but not in negative selection in the thymus.

Carcinoma e leucemia da glândula lacrimal: a raridade num caso clinico

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2014

Small clonal B-cell population in the bone marrow as a possible tool in the diagnosis of occult primary parotid lymphoma

Case Description: An 82-years old Hispanic woman with a past medical history significant for pulmonary thromboembolism on oral anticoagulation, rheumatoid arthritis, and hypertension developed a new onset thrombocytopenia. Clinical Findings: Small clonal B-cells populations (SCBP) also known as monoclonal B-cell lymphocytosis was found as part of the workup for an idiopathic thrombocytopenia and lead ultimately to the diagnosis of parotid primary follicular lymphoma coexisting with Warthin tumor involving the bone marrow in a small extent and oncocytic papilloma located in the maxillary sinus. Treatment and Outcome: Patient was treated with Rituximab monotherapy with improvement on her platelet count. Clinical relevance: Although it is unclear the role of this clonal cells, they may work as a possible diagnostic tool for occult lymphomas. Further prospective studies are needed to confirm this possible association.