Myelodysplastic syndrome progression to acute myeloid leukemia in a cat FeLV seroreactive

Background: Acute myeloid leukemia (AML) is a group of non-lymphoid hematological tumors characterized by aberrant proliferation and/or decreased apoptosis of a clone of non-mature cells, resulting in the accumulation of immature blast cells in the bone marrow and peripheral blood. It is considered rare, as it represents 10% of neoplasms of hematopoietic origin. However, it is known that felines seroreactive for FIV and FeLV are more predisposed and reports of this type of leukemia in cats in the literature are scarce. Thus, the objective of this study was to evaluate the blood and bone marrow of a cat seroreactive for FeLV that presented with myelodysplastic syndrome that progressed to acute myeloid leukemia. Case: A 6-year-old male mixed-breed cat, neutered, seroreactive for FeLV, showed apathy, weight loss, and pale mucous membranes. Initial peripheral blood smear evaluation revealed hypochromic normocytic anemia, leukopenia, neutropenia, lymphopenia, and thrombocytosis with many macropackets and giant platelets. Based on this blood picture, a long-spectrum antimicrobial therapy with amoxicillin and clavulanate [Clavulin® BD - 25 mg/kg, every 12 h] was started. Granulocyte colony stimulating factor used filgrastim (rHu G-CSF) [Fiprina® - 5 µg/kg, SC, every 48 h] and appetite stimulant mirtazapine [Mirtz® - 2 mg/cat, orally, every 48 h] were used to correct leukopenia and nutritional status, respectively. Follow-up blood smear evaluation on the 30th day showed persistence of the hematological changes noticed earlier. A bone marrow puncture was performed, and immunosuppressive therapy with prednisolone [Predsim® - 4 mg/kg, orally, every 24 h] was initiated. The aspirated material showed increased cellularity for age, decreased myeloid:erythroid ratio, and 39.8% of blasts of myeloid origin. An average of 17.7 megakaryocytes were observed per field (10x magnification). Bone marrow cytological evaluation suggested acute myeloid leukemia with dysmegakaryocytopoiesis. After the diagnosis, the examinations were repeated monthly, and there was still intense leukopenia. However, in view of the stable clinical status and leukopenia with neutropenia, treatment for leukemia was not instituted and only supportive treatment was administered when necessary. Eight months after the diagnosis, clinical status had worsened, and unlike the earlier hemograms, global leukocyte count had increased with predominant lymphocytosis (95% of the total leukocytes) with atypical lymphocytes. The cat died a few days later. Discussion: Bone marrow evaluation is indicated when peripheral blood cell abnormalities are present and cannot be explained in the context of the clinical history. In the present report, the bone marrow aspirate was hypercellular (cellularity above 75%); however, intense leukopenia was observed in the peripheral blood. In myelodysplastic syndromes, it is common for the bone marrow to be normal to hypercellular, which occurs when there is a greater production of myeloid or erythroid cell lines in response to the loss, destruction, or consumption of cells. Despite this, cytopenias may be present in the peripheral blood, since the defective cells undergo apoptosis and die before being released into the circulation, characterizing inefficient hematopoiesis. The diagnosis of acute leukemia comprises a variety of hematopoietic neoplasms that are complex and unique. Each acute leukemia subtype has defining characteristics that affect the prognosis and treatment of each animal.

Hepatic myelolipomas in Callimico goeldii (Thomas, 1904) kept in captivity

Myelolipoma is an unusual benign neoplasm in veterinary medicine. This work intended to report the occurrence of hepatic myelolipomas in Neotropical primates of the Callimico goeldii species kept in captivity. These cases were diagnosed during necropsy in a survey on liver neoplasms in the period of 2004 to 2008. Two cases were found in adult male, and two in adult female animals. The diagnoses were obtained through data analysis of necropsy records, pathological examination of the cases, and histological confirmation. Three (75%) of the animals showed clinical signs of progressive weight loss, and two (50%) of them exhibited regional abdominal bloating. The livers had protrusions of pale yellow color on the surface of all lobes. Histologically, the tumors were formed by mature myeloid tissue with high hematopoietic cellularity, represented by the megakaryocytes and meroblastic cells and immature erythroblasts. We conclude that non-human primates of the Callimico goeldii species might have predisposition for liver myelolipoma, which are neoplasms that can lead to the failure and destruction of this organ.

Hepatic myelolipomas in Callimico goeldii (Thomas, 1904) kept in captivity

Myelolipoma is an unusual benign neoplasm in veterinary medicine. This work intended to report the occurrence of hepatic myelolipomas in Neotropical primates of the Callimico goeldii species kept in captivity. These cases were diagnosed during necropsy in a survey on liver neoplasms in the period of 2004 to 2008. Two cases were found in adult male, and two in adult female animals. The diagnoses were obtained through data analysis of necropsy records, pathological examination of the cases, and histological confirmation. Three (75%) of the animals showed clinical signs of progressive weight loss, and two (50%) of them exhibited regional abdominal bloating. The livers had protrusions of pale yellow color on the surface of all lobes. Histologically, the tumors were formed by mature myeloid tissue with high hematopoietic cellularity, represented by the megakaryocytes and meroblastic cells and immature erythroblasts. We conclude that non-human primates of the Callimico goeldii species might have predisposition for liver myelolipoma, which are neoplasms that can lead to the failure and destruction of this organ.(AU)

Quantitative analysis of bone marrow in pancytopenic dogs / Análise quantitativa de medula óssea em cães pancitopênicos

The pancytopenia can be associated with intra and extra medullary disorders. When the etiology is not obvious, the examination of bone marrow is necessary. The study aims to report and discuss quantitative amendments in bone marrow and their causes in dogs with pancytopenia. Bone marrow aspirate was obtained from 65 dogs with pancytopenia over a period of 13 consecutive months for preparation of smears stained by Giemsa and observed in light microscopy. Five hundred cells differential count was held; and assessed myeloid:erythroid ratio, cellularity, megakaryocytes and direct parasitological examination. The data were evaluated by the Chi-square statistical test. Blood tests of 3120 canines with several clinical changes were analyzed to identify pancytopenia, which accounted for 167 (5.4%) dogs. Interpretation of quantitative characteristics was carried out from the bone marrow smear in 65 pancytopenic dogs and the etiology was established in 40 (61.5%) of these, which included infection by E. canis and L. chagasi, idiopathic aplastic anemia, chronic renal failure and co-infections. In 17 (26.2%) animals were not observed medullary changes. The most bone marrow change was observed myeloid and erythroid hypoplasia in 17 (26.2%) dogs, followed by myeloid and erythroid hyperplasia (24.6%). The myelogram association to the blood cell count allowed the identification of medullary findings and its participation on the occurrence of pancytopenia cases. The number of cases resulting from infectious diseases was 38 (58.5%) in canine assessed: significant number due to its endemic characteristic of the study region.

A pancitopenia pode estar associada a distúrbios intra e extra medulares. Quando a etiologia não é óbvia, o exame da medula óssea é necessário. Este estudo tem como objetivo relatar e discutir alterações quantitativas na medula óssea e suas causas em cães com pancitopenia. De 65 cães pancitopêncicos atendidos durante um período de 13 meses consecutivos, foram realizados aspirados de medula óssea, corados com Giemsa, e observados em microscopia de luz. Quinhentas células foram observadas para contagem diferencial, razão mieloide: eritróide, celularidade, megacariócitos e exame parasitológico direto. Os dados foram avaliados pelo teste estatístico Qui-quadrado. Hemograma de 3120 caninos com diversas alterações clínicas foram analisadas para identificar a pancitopenia, encontrada em 167 (5,4%) cães. A interpretação das características quantitativas foi realizada a partir do esfregaço de medula óssea em 65 cães pancitotopênicos e a etiologia foi estabelecida em 40 (61,5%), incluindo infecção por E. canis e L. chagasi, anemia aplástica idiopática, insuficiência renal crônica e co-infecções. Em 17 (26,2%) cães não foram observadas alterações medulares. A alteração de medula óssea mais observada foi a hipoplasia mielóide e eritróide em 17 (26.2%) cães, seguido pela hiperplasia mielóide e eritróide (24.6%). A associação do mielograma ao hemograma permitiu a identificação de achados medulares e sua participação na ocorrência de casos de pancitopenia. O número de casos resultantes de doenças infecciosas foi de 38 (58,5%) em caninos avaliados: número significativo devido à característica endêmica da região do estudo.

Quantitative analysis of bone marrow in pancytopenic dogs / Análise quantitativa de medula óssea em cães pancitopênicos

The pancytopenia can be associated with intra and extra medullary disorders. When the etiology is not obvious, the examination of bone marrow is necessary. The study aims to report and discuss quantitative amendments in bone marrow and their causes in dogs with pancytopenia. Bone marrow aspirate was obtained from 65 dogs with pancytopenia over a period of 13 consecutive months for preparation of smears stained by Giemsa and observed in light microscopy. Five hundred cells differential count was held; and assessed myeloid:erythroid ratio, cellularity, megakaryocytes and direct parasitological examination. The data were evaluated by the Chi-square statistical test. Blood tests of 3120 canines with several clinical changes were analyzed to identify pancytopenia, which accounted for 167 (5.4%) dogs. Interpretation of quantitative characteristics was carried out from the bone marrow smear in 65 pancytopenic dogs and the etiology was established in 40 (61.5%) of these, which included infection by E. canis and L. chagasi, idiopathic aplastic anemia, chronic renal failure and co-infections. In 17 (26.2%) animals were not observed medullary changes. The most bone marrow change was observed myeloid and erythroid hypoplasia in 17 (26.2%) dogs, followed by myeloid and erythroid hyperplasia (24.6%). The myelogram association to the blood cell count allowed the identification of medullary findings and its participation on the occurrence of pancytopenia cases. The number of cases resulting from infectious diseases was 38 (58.5%) in canine assessed: significant number due to its endemic characteristic of the study region.(AU)

A pancitopenia pode estar associada a distúrbios intra e extra medulares. Quando a etiologia não é óbvia, o exame da medula óssea é necessário. Este estudo tem como objetivo relatar e discutir alterações quantitativas na medula óssea e suas causas em cães com pancitopenia. De 65 cães pancitopêncicos atendidos durante um período de 13 meses consecutivos, foram realizados aspirados de medula óssea, corados com Giemsa, e observados em microscopia de luz. Quinhentas células foram observadas para contagem diferencial, razão mieloide: eritróide, celularidade, megacariócitos e exame parasitológico direto. Os dados foram avaliados pelo teste estatístico Qui-quadrado. Hemograma de 3120 caninos com diversas alterações clínicas foram analisadas para identificar a pancitopenia, encontrada em 167 (5,4%) cães. A interpretação das características quantitativas foi realizada a partir do esfregaço de medula óssea em 65 cães pancitotopênicos e a etiologia foi estabelecida em 40 (61,5%), incluindo infecção por E. canis e L. chagasi, anemia aplástica idiopática, insuficiência renal crônica e co-infecções. Em 17 (26,2%) cães não foram observadas alterações medulares. A alteração de medula óssea mais observada foi a hipoplasia mielóide e eritróide em 17 (26.2%) cães, seguido pela hiperplasia mielóide e eritróide (24.6%). A associação do mielograma ao hemograma permitiu a identificação de achados medulares e sua participação na ocorrência de casos de pancitopenia. O número de casos resultantes de doenças infecciosas foi de 38 (58,5%) em caninos avaliados: número significativo devido à característica endêmica da região do estudo.(AU)

AVALIAÇÃO DO MIELOGRAMA E DA CARGA PARASITÁRIA EM CÃES NATURALMENTE INFECTADOS POR Leishmania infantum SUBMETIDOS A TRATAMENTO EXPERIMENTAL COM DOMPERIDONA ASSOCIADA A ALOPURINOL

A leishmaniose visceral canina (LVC) é uma doença sistêmica crônica, na qual os cães podem ser assintomáticos como também podem apresentar uma variedade de sinais clínicos inespecíficos. As alterações nos exames laboratoriais são uma manifestação importante na LVC e que, se não acompanhados, pode levar o animal a morte. Alguns estudos já vêm mostrando que essas alterações podem estar relacionadas as mudanças na produção e/ou diferenciação das diferentes linhagens celulares na medula óssea, em consequência da infecção por Leishmania sp. Dessa forma, o objetivo desse trabalho foi avaliar as alterações no mielograma e quantificar a carga parasitária na medula óssea de cães naturalmente infectados por Leishmania infantum e submetidos a tratamento experimental. Para isso, foram utilizados 10 cães, adultos, que foram tratados por 30 dias com a associação de alopurinol (10mg/kg/BID) e domperidona (1mg/kg/SID). As punções de medula óssea foram realizadas no dia zero e 30 dias após o início do tratamento, onde foram confeccionados esfregaços em lâminas de vidro, fixadas e coradas para avaliação citológica. Para a qPCR a medula óssea foi acondicionada em micrutubos com EDTA 3% para posterior extração de DNA e quantificação. O mielograma dos animais revelou, no dia zero, redução no número de metarrubrícitos, promielócito, mielócito neutrofílicos, metamielócito neutrofílicos, bastonete neutrofílicos e megacariócitos, e aumento no número de neutrófilos e macrófagos. No dia 30 foi observado redução no número de metarrubrícitos, prorrubrícitos, promielócito, mielócito neutrofílicos, metamielócito neutrofílicos, bastonete neutrofílicos, e megacariócitos. Observouse também aumento no número de neutrófilos, macrófagos e plasmócitos, além de aumento discreto na relação mieloide:eritróide. Com relação as alterações morfológicas, foi observado binucleação celular (2/10) e presença de mitoses atípicas (2/10). Leucofagocitose foi observada em 20% (2/10) dos animais. Em 70% dos animais, formas amastigotas de Leishmania sp. foram visualizadas após tratamento. A carga parasitária da medula óssea revelou que 54,5% dos animais apresentaram diminuição da carga parasitária, enquanto 45,4% apresentaram aumento na quantificação 30 dias após o tratamento. A quantificação média no dia zero e no dia 30 foi de 4.424,82 e 16.673,2 parasitas/ L, respectivamente, mas não houve diferença significativa entre os períodos estudados (p = 0,05). Com esses resultados sugere-se que o mielograma não seja a melhor ferramenta para o acompanhamento de cães com LVC quando se objetiva avaliar a resposta do paciente num curto período de tratamento e que 30 dias de tratamento não é suficiente para observar uma resposta parasitológica satisfatória, sendo necessário um estudo de longo prazo para entender os possíveis mecanismos associados a carga de parasitas da medula óssea durante o tratamento da leishmaniose visceral canina.

A Canine Visceral Leishmaniasis (CVL) is a chronic systemic disease, in which dogs can be asymptomatic but can also exhibit a variety of nonspecific clinical signs. Changes in laboratory tests are an important manifestation in CVL and, if not followed up, can lead to the death of an animal. Some studies already show that these changes may be related to changes in the production and/or differentiation of different cell lines in the bone marrow, as a result of infection by Leishmania sp. Thus, the objective of this study was to evaluate changes in the myelogram and quantify the parasitic load on the bone marrow of dogs naturally infected with Leishmania infantum and submitted to experimental treatment. For that, 10 adult dogs were used, which were treated for 30 days with the combination of allopurinol (10mg/kg/BID) and domperidone (1mg/ kg/SID). Bone marrow punctures were performed on day zero and 30 days after the start of treatment, where smears were made on glass slides, fixed and stained for cytological evaluation. For the qPCR, the bone marrow was packed in micrutubes with 3% EDTA for subsequent DNA extraction and quantification. The animals' myelogram revealed, on day zero, a reduction in the number of metarubricyte, promyelocytes, neutrophilic myelocytes, neutrophilic metamyelocytes, neutrophilic band and megakaryocytes, and an increase in the number of neutrophils and macrophages. On the 30th, a reduction in the number of metarubricytes, prorubrocytes, promyelocytes, neutrophilic myelocytes, neutrophilic metamyelocytes, neutrophilic band and megakaryocytes was observed. There was also an increase in the number of neutrophils, macrophages and plasma cells, in addition to a slight increase in the myeloid:erythroid ratio. Regarding morphological changes, cell binucleation (2/10) and atypical mitosis (2/10) were observed. Leukophagocytosis was observed in 20% (2/10) of the animals. In 70% of the animals, amastigote forms of Leishmania sp. were visualized after treatment. The bone marrow parasitic load revealed that 54.5% of the animals showed a decrease in the parasitic load, while 45.4% showed an increase in quantification 30 days after treatment. The mean quantification on day zero and day 30 was 4,424.82 and 16,673.2 parasites/ L, respectively, but there was no significant difference between the periods studied (p=0.05). With these results, it is suggested that the myelogram is not the best tool for monitoring dogs with CVL when the objective is to assess the patient's response in a short period of treatment and that 30 days of treatment is not enough to observe a satisfactory parasitological response, requiring a long-term study to understand the possible mechanisms associated with the load of bone marrow parasites during the treatment of canine visceral leishmaniasis.

Estudo da interação entre plaquetas e leptospiras

: A leptospirose é uma zoonose mundialmente disseminada e endêmica nas regiões tropicais e subtropicais do mundo. É causada por espiroquetas patogênicas do gênero Leptospira, que colonizam os túbulos renais proximais de animais domésticos ou silvestres e são eliminadas no ambiente externo pela urina. A transmissão ocorre por meio de contato direto com tecidos, fluidos corporais e urina de animais infectados, ou pela exposição à água ou solo contaminado. Esta doença apresenta grande impacto na saúde pública, além de ser responsável por prejuízos na economia pecuária, pois interfere na produção de leite e causa distúrbios reprodutivos nos animais de criação, como abortamentos e infertilidades. As plaquetas são pequenos fragmentos citoplasmáticos, abundantes no sangue e originados dos megacariócitos da medula óssea. Classicamente, são conhecidas por atuarem no processo de hemostasia, garantindo a manutenção do fluxo sanguíneo e da integridade vascular. No entanto, vários estudos têm demonstrado que as plaquetas, também, participam de processos inflamatórios, do reparo de tecidos, da angiogênese e de mecanismos de defesa do organismo a infecções. Na forma grave da leptospirose, a trombocitopenia tem sido relatada. Provavelmente, os baixos níveis de plaquetas no sangue ocorrem devido à lesão vascular e ao aumento no consumo de plaquetas nas hemorragias observadas durante a infecção por leptospiras. A trombocitopenia também pode ser causada pela ação direta das leptospiras sobre as plaquetas. Neste trabalho, foi investigado a existência de uma possível interação das leptospiras com as plaquetas. Os resultados obtidos, mostraram que os protocolos utilizados para a obtenção das amostras de sangue total, plasma rico em plaquetas e plaquetas lavadas são adequados para a avaliação da possível capacidade das leptospiras em ativar plaquetas. Entretanto, nenhuma das estirpes de leptospiras testadas foram capazes de ativar diretamente as plaquetas em um tempo máximo de 45 minutos, mesmo com diferentes proporções de bactéria:plaqueta. As leptospiras também foram avaliadas quanto a sua capacidade de alterar a agregação plaquetária provocada por agonistas conhecidos (colágeno, TRAP ou ADP). Apesar da agregação plaquetária na presença das leptospiras serem semelhantes ou maiores que o controle positivo, esses valores não foram estatisticamente significantes. Um lisado total da estirpe patogênica de leptospira, L1-130, foi avaliado quanto a capacidade de se ligar a lisados de diferentes frações plaquetárias, previamente ativadas ou não por ADP, através de ensaios de ELISA. O lisado da fração de plaquetas lavadas foi o único que apresentou valores significativos de interação com o lisado de L1-130. Por último, as plaquetas foram avaliadas quanto a sua capacidade de inibir o crescimento bacteriano, com o indicador de crescimento Resazurina. Estes ensaios não foram capazes de identificar uma ação microbicida por parte das plaquetas sobre a estirpe de leptospira utilizada. Os resultados obtidos, neste trabalho, mostraram que as leptospiras não foram capazes de ativar diretamente a agregação plaquetária, porém, a hipótese de interação entre as plaquetas e as leptospiras não deve ser totalmente descartada, uma vez que a fração de plaquetas lavadas foi capaz de aderir ao lisado da estirpe L1-130, por isso novos estudos devem ser realizados.

Leptospirosis is a widespread and endemic zoonosis in the tropical and subtropical regions of the world. It is caused by pathogenic spirochetes of the Leptospira genus, which colonize the proximal renal tubules of domestic or wild animals and are excreted in the environment by the urine. Transmission occurs through the direct contact with tissues, body fluids, and urine of infected animals, or through exposure to contaminated water or soil. This disease has great impact on public health, besides being responsible for losses in the livestock economy, because it interferes in the milk production and causes reproductive disorders in the livestock, such as abortion and infertility. Platelets are small cytoplasmic fragments, abundant in the blood and originated from the megakaryocytes of the bone marrow. Classically, they are known to act in the process of hemostasis, ensuring the maintenance of the blood flow and the vascular integrity. However, several studies have shown that platelets also participate in inflammatory processes, tissue repair, angiogenesis and mechanisms of defense of the body to infections. In the severe form of leptospirosis, thrombocytopenia has been reported. It is probable that the low platelet levels in the blood occur due to vascular injury and due to an increase in the consumption of blood, both observed during leptospiral infection. Thrombocytopenia can also be caused by the direct action of leptospires on platelets. In this work, the existence of a possible interaction between leptospires and human platelets was investigated. The results showed that the protocols used to obtain the samples of whole blood, platelet rich plasma and washed platelets are adequate for the evaluation of the possible ability of leptospires to activate platelets. However, none of the leptospira strains tested were able to directly activate the platelets in a maximum time of 45 minutes, even with different proportions of bacterium:platelet. Leptospires were also evaluated for their ability to alter platelet aggregation caused by known agonists (collagen, TRAP or ADP). Although platelet aggregation in the presence of leptospires was similar to or greater than the positive control, these values were not statistically significant. The total lysate of the pathogenic strain of leptospira, L1-130, was evaluated for the ability to bind to lysates of different platelet fractions, previously activated or not by ADP, by ELISA. The lysate of the washed platelets fraction was the only one that presented significant values of interaction with the L1-130 lysate. Finally, platelets were evaluated for their ability to inhibit bacterial growth, with the Resazurin growth indicator. These assays were not able to identify a microbicidal action by the platelets on the used leptospira strain. The results obtained in this work show that leptospires were not able to directly activate platelet aggregation, however, the hypothesis of interaction between platelets and leptospires should not be totally discarded, since some the washed platelet lysate was able to bind to the strain L1-130 lysate, so further studies should be carried out on this subject.

AVALIAÇÃO DO EFEITO PROTETOR DA MELATONINA EXÓGENA SOBRE OS NEONATOS DE MATRIZES SUBMETIDAS AO CONSUMO CRÔNICO DE ÁLCOOL DURANTE A PRENHEZ

(3 g/kg/dia) e melatonina (15 mg/kg/dia). Após o nascimento, as matrizes e 10 filhotes (cinco machos e cinco fêmeas) de cada grupo experimental foram anestesiados para coleta do sangue e fígado das mães e do sangue, fígado e cérebro dos neonatos para verificação da frequência de danos no DNA pelo ensaio cometa. O sangue ainda foi usado para o teste do micronúcleo. Análises sobre tamanho e peso ao nascer dos neonatos, assim como avaliações morfométricas, histoquímicas (quantificação de glicogênio e colágeno) e imunohistoquímicas (fator TNF- e IL-6) no fígado desses animais também foram realizadas. Os resultados demonstraram um aumento significativo de dano no DNA das células sanguíneas e hepáticas das matrizes e das proles do grupo álcool, bem como no cérebro desses neonatos. Os tratamentos com melatonina (10 e 15 mg/kg/dia) reduziram significativamente a genotoxicidade causada pelo etanol no sangue das mães e dos neonatos (machos e fêmeas), no fígado das matrizes e dos filhotes machos e no cérebro da prole de fêmeas. Mostrou-se ainda que apenas a prole de fêmeas exposta ao consumo materno de álcool apresentou frequência maior de micronúcleos em eritrócitos policromáticos. Além disso, a exposição intrauterina ao álcool provocou redução significativa no comprimento e peso ao nascer dos neonatos. Ademais, reduziu o número de hepatócitos e de sua área nuclear, aumentou a área citoplasmática dessas células, diminuiu o acúmulo de glicogênio hepático e elevou os níveis das citocinas pró-inflamatórias TNF- e IL-6. Contudo, o número de megacariócitos e a deposição de colágeno não foram alterados. Os tratamentos com melatonina a 10 e a 15 mg/kg durante a prenhez protegeram os neonatos contra as injúrias provocadas pelo consumo materno de álcool sobre o crescimento, peso ao nascer e morfofisiologia hepática. Assim, concluímos que o tratamento com melatonina exógena pode ser uma estratégia eficaz na proteção contra danos induzidos pela exposição pré-natal ao álcool.

Alcohol consumption during pregnancy is a serious public health problem because it increases the risk of spontaneous abortions, mental retardation and congenital anomalies, compromising healthy fetal development. Production of acetaldehyde and increase in the liberation of free radicals due to the metabolism of ethanol are the main factors that contribute to the damages induced by alcohol. These products react and injure proteins, lipids and DNA of the cells and thus impair organogenesis and fetal physiology. Melatonin is a powerful antioxidant capable of freely crossing the morphological and physiological barriers found in cells and cell compartments, including the nucleus and mitochondria, protecting cell membranes, proteins and nuclear and mitochondrial genomes. The objective of this study was to evaluate the protective effect of exogenous melatonin on the neonates of matrices submitted to chronic alcohol consumption during pregnancy. Twenty pregnant rats were used and divided into the groups: I - Rats receiving distilled water (control); II - Rats receiving absolute ethyl alcohol (3 g/kg/day); III - Rats receiving absolute ethyl alcohol (3 g/kg/day) and melatonin (10 mg/kg/day); IV - Rats receiving absolute ethyl alcohol (3 g/kg/day) and melatonin (15 mg/kg/day). After birth, dams and 10 neonates (five males and five females) of each experimental group were anesthetized to collect of the dams' blood and liver and of the neonates' blood, liver and brain to verify the frequency of DNA damage by the comet assay. Blood was also used for the micronucleus test. Analyzes of size and birth weight of newborns, as well as, morphometric, histochemical (quantification of glycogen and collagen) and immunohistochemical (tumor necrosis factor alpha - TNF- and interleukin 6 - IL-6) evaluations in the liver of these animals were also performed. Our results demonstrated a significant increase in DNA damage in the blood and liver cells of the dams and offspring of the alcohol group as well as in the brains of these neonates. Treatments with melatonin (10 and 15 mg/kg/day) significantly reduced the genotoxicity caused by ethanol in the blood of dams and neonates (males and females), liver of dams and male offspring, and in the brain of offspring of females. It was also shown that only the offspring of females exposed to maternal alcohol consumption showed a higher frequency of micronuclei in polychromatic erythrocytes. In addition, intrauterine exposure to alcohol resulted in a significant reduction in neonatal length and birth weight. Moreover, it reduced the number of hepatocytes and their nuclear area, increased the cytoplasmic area of these cells, decreased the accumulation of hepatic glycogen and raised the levels of the proinflammatory cytokines TNF- and IL-6. However, the number of megakaryocytes and collagen deposition were not altered. Treatments with melatonin at 10 and 15 mg/kg during pregnancy protected the neonates against injuries caused by maternal alcohol consumption on growth, birth weight and hepatic morphophysiology. Thus, we conclude that treatment with exogenous melatonin may be an effective strategy in protecting against damage induced by intrauterine exposure to alcohol.

Hepatic damage in newborns from female rats exposed to the pesticide derivative ethylenethiourea / Lesões hepáticas em recém-nascidos de ratas expostas ao derivado de agrotóxico etilenotioureia

PURPOSE: To evaluate hepatic morphological-histological abnormalities in newborns from female rats exposed to ethylenethiourea. METHODS: A randomized study was conducted on fifty-five newborn Wistar rats were studied: 34 in the experimental group, whose mothers had been exposed to 1% ethylenethiourea; and 21 in the control group, whose mothers had received 0.9% physiological solution. The solution was administered via gavage on the 11th day of gestation. Cesarean section was performed on the 20th day of gestation. The newborns' livers were examined and any morphological-histological abnormalities were registered. The presence of megakaryocytes was quantified in 50 microscope fields, as the total number of these cells per mm². RESULTS: The entire experimental group presented abnormalities of embryonic formation, with musculoskeletal anomalies, digestive system anomalies, hepatic congestion and friability, hydrops and delayed intrauterine growth. The histopathological analysis showed that morphological-histological hepatic destructuring had occurred in all entire experimental with removal of the hepatic trabeculae and severe hepatic megakaryocytosis. The mean megakaryocyte density ranged from 107.9 to 114.2 per mm², and it was eight times greater than in the control group, thus characterizing a situation of extramedullary hematopoiesis. CONCLUSION: The fetal exposure to ethylenethiourea caused hepatic damage characterized by severe extramedullary hematopoiesis.(AU)

OBJETIVO: Avaliar alterações hepáticas morfohistológicas em recém-nascidos de ratas prenhes expostas à etilenotioureia. MÉTODOS: Realizado ensaio randomizado em animais de experimentação, onde foram estudados 55 recém-nascidos de ratas Wistar, 34 do Grupo Experimento, expostas a etilenotioureia 1% e 21 do Grupo Controle, em que a rata prenhe recebeu solução fisiológica 0,9%, ambos por gavagem no 11º dia de gestação. Realizada no 20º dia de gestação cesariana, analisados os fígados dos recém-nascidos e registradas as alterações morfohistológicas. Realizou-se a quantificação dos megacariócitos em 50 campos microscópicos, avaliando a quantidade total destas células por mm². RESULTADOS: Todos os recém-nascidos do Grupo Experimento apresentaram alterações na formação embrionária, com anomalias musculoesqueléticas, anormalidades do sistema digestório, congestão e friabilidade hepática, hidropisia e crescimento intrauterino retardado. A análise histopatológica mostrou desestruturação hepática morfohistológica em todos os recém-nascidos expostos à etilenotioureia, com destrabeculação dos hepatócitos e intensa megacariocitose hepática, apresentando média da densidade de megacariócitos de 107,9 até 114,2 por mm² sendo cerca de oito vezes maior que no Grupo Controle, caracterizando hematopoese extramedular. CONCLUSÃO: A exposição fetal a etilenotioureia provocou danos hepáticos caracterizados pela intensa hematopoese extramedular.(AU)

Plaquetas reticuladas na avaliação da trombopoiese medular em cães

O objetivo do presente estudo foi avaliar a importância das plaquetas reticuladas nas condições trombocitopênicas associadas a hipoplasia de megacariócitos e a outras etiologias sem alteração no número de megacariócitos. Para tanto foram utilizados 30 cães sadios adultos (Grupo controle); 15 cães com trombocitopenia (< 100.000 plaquetas/mL), por causas diversas que não sejam por hipoplasia megacariocítica (Grupo A) e 15 cães com trombocitopenia (< 100.000 plaquetas/mL) e com hipoplasia megariocítica (Grupo B), constatadas por meio de citologia aspirativa de medula óssea. Foi coletado sangue e extraído o plasma rico em plaquetas para a realização da quantificação das plaquetas reticuladas em citometria de fluxo e colheita de medula óssea para a análise do número de megacariócitos por duas técnicas distintas e correlação com as plaquetas reticuladas. Não foi observada diferença estatística (p>0,05) entre as duas técnicas de quantificação de megacariócitos. Foi observada diferença estatística (p<0,05) para as plaquetas reticuladas, sendo superior nos grupos A e B, em relação ao grupo controle. Não houve correlação entre plaqueta reticulada e megacariócitos medulares. A ausência de correlação observada não nos permite estabelecer relações de contagem de PR com o aumento do número de megacariócitos na medula óssea

The aim of this study was to evaluate the reticulated platelet importance in evaluation of platelet production in thrombocytopenic conditions associated with megakaryocytic hypoplasia and other conditions with adequate number of bone marrow megacaryocytes. These study were obtained from 30 healthy dogs (control group), 15 thrombocytopenic dogs (< 100,000 platelets/?L) without megakaryocytic hipoplasia (group A) and 15 thrombocytopenic dogs (< 100,000 platelets /?L) with megakaryocytic hipoplasia (group B). Blood samples were collected and the platelet rich plasma (PRP) was extracted for quantification of reticulated platelets in flow cytometry, megakaryocytes were quantified in marrow particles, collected from aspiration cytology and correlated to reticulated platelets counts. No statistical significance (p>0.05) was observed between two megakaryocytes quantification techniques. For reticulated platelets was observed statistical significance difference (p<0.05), values from groups A and B were higher than control group. No correlation was verified between reticulated platelets and marrow megakaryocytes. The absence of correlation do not allow us to establish relationship of reticulated platelets with increase production of bone marrow megakaryocytes

Morphometry of megakaryocytes in the liver of New Zealand White rabbits during intrauterine and postnatal development

The hepatic megakaryocytic cells of New Zealand White rabbit in the intrauterine phase and in the immediate postnatal period were studied. Statistical analysis of the data concerning the cytoplasm and nucleus of those cells, i.e., area, perimeter, maximum diameter, minimum diameter, volume and shape factor, presented significant differences (p 0.01) for F values concerning the life phases studied on15th, 22nd and 29th day of intrauterine life and 10th day of postnatal life, and for F values for animal within each phase. The Tukeys test showed that most of the parameters studied in the cytoplasm and nucleus of these megakaryocytic cells presented the lowest values on the 15th day of intrauterine life and the highest on the 22nd day of the same phase.

As células megacariocíticas hepáticas de coelhos da raça Nova Zelândia Branco foram estudadas na fase intra-uterina e no período pós-natal imediato. A análise estatística dos dados referentes ao citoplasma e núcleo dessas células, isto é, área, perímetro, diâmetro máximo, diâmetro mínimo, volume e fator de forma apresentaram diferenças significativas (p 0,01) para os valores de F relativos às fases estudadas no 15º, 22º e 29º dia de vida intra-uterina e 10º dia de vida pós-natal, e para os valores de F para animal dentro de cada fase. O teste de Tukey mostrou que a maioria dos parâmetros estudados no citoplasma e núcleo dessas células apresentou os menores valores no 15º dia de vida intra-uterina e os maiores no 22º dia da mesma fase.

Morphometry of megakaryocytes in the liver of New Zealand White rabbits during intrauterine and postnatal development

The hepatic megakaryocytic cells of New Zealand White rabbit in the intrauterine phase and in the immediate postnatal period were studied. Statistical analysis of the data concerning the cytoplasm and nucleus of those cells, i.e., area, perimeter, maximum diameter, minimum diameter, volume and shape factor, presented significant differences (p 0.01) for F values concerning the life phases studied on15th, 22nd and 29th day of intrauterine life and 10th day of postnatal life, and for F values for animal within each phase. The Tukey’s test showed that most of the parameters studied in the cytoplasm and nucleus of these megakaryocytic cells presented the lowest values on the 15th day of intrauterine life and the highest on the 22nd day of the same phase.

As células megacariocíticas hepáticas de coelhos da raça Nova Zelândia Branco foram estudadas na fase intra-uterina e no período pós-natal imediato. A análise estatística dos dados referentes ao citoplasma e núcleo dessas células, isto é, área, perímetro, diâmetro máximo, diâmetro mínimo, volume e fator de forma apresentaram diferenças significativas (p 0,01) para os valores de F relativos às fases estudadas no 15º, 22º e 29º dia de vida intra-uterina e 10º dia de vida pós-natal, e para os valores de F para animal dentro de cada fase. O teste de Tukey mostrou que a maioria dos parâmetros estudados no citoplasma e núcleo dessas células apresentou os menores valores no 15º dia de vida intra-uterina e os maiores no 22º dia da mesma fase.