On a Haemogregarine sp. [protozoa, apicomplexa, adeleina] naturally infecting the viper Bitis arientans in Saudi Arabia with reference to the host-parasite relationship

The study described the developmental stages of a haemogregarine species in the blood and tissues of the viper Bitis arientans. Two out of 9 [22.2%] snakes from the south western region of Saudi Arabia, and recorded for the first time in such locality. The erythrocytic parasites were differentiated into three forms: the youngest form [trophozoite] measuring 7.34 +/- 0.16 x 3.38 +/- 0.07 micro m; the intermediate form [developing gametocyte] measuring 13.36 +/- 0.20 x 5.11 +/- 0.11 micro m and the largest form [mature gametocyte] measuring 18.69 +/- 0.32 x 4.32 +/- 0.16 micro m. None of the leucocytes seemed to be parasitized. Also, two types of meronts were detected in lung endothelial cells of infected vipers. Small meronts [micromeronts] measured 21.86 +/- 0.28 x 16.13 +/- 0.25 micro m and yielded about 12 merozoites. The large meronts [macromeronts] measured 38.09 +/- 0.33 x 21.52 +/- 0.32 micro m and yielded 28-42 merozoites. Random distribution of nuclei was observed in early meronts of both sizes, meanwhile peripheral arrangement of nuclei characterizing the subsequent developing events of meronts [ectomerogony]. Histopatho-logical studies showed that the infected erythrocytes were hypertrophied, mechanically stretched and their cytoplasm was faintly stained due to dehaemoglobinization. The host cell nucleus was elongated and laterally displaced. Trabeculae of the infected lung exhibited marked thickening and alveoli were collapsed in various degrees. Haemorrhagic foci and spongy structures were detected in some infected lung tissues. Formation of fibrous tissues around the meronts was seen in some foci

Assessment of the mutagenic, antimutagenic and cytotoxic activities of ethanolic extract of araticum (Annona crassiflora Mart. 1841) by micronucleus test in mice

A typical Brazilian plant, araticum (Annona crassiflora Mart.), is widely used in humans as therapeutic medicine to treat several diseases such as diarrhea, rheumatism and syphilis. It contains acetogenins which present cytotoxic, antitumogenic, and antiparasitic properties. In this study, mutagenic, antimutagenic and cytotoxic effects of araticum leaves ethanolic extract were evaluated by micronucleus test in mice. To evaluate the mutagenic activity, animals were treated with ethanolic extract of araticum (EEA) using 10, 20, 50, 100 and 160 mg.kg-1. For all doses, micronucleated polychromatic erythrocytes (MNPCE) frequency was evaluated at 24, 48 and 72 hours after treatment. To evaluate the antimutagenic activity, animals were treated with 10, 20, 50 and 100 mg.kg-1 of EEA and 4 mg.kg-1 of MMC simultaneously. The frequency of MNPCE was evaluated 36 hours after exposure. Cytotoxicity was evaluated by the polychromatic and normochromatic erythrocytes ratio (PCE/NCE). In the mutagenicity assessment, all doses of EEA resulted in no significant increase of MNPCE (P > 0.05), compared to solvent- control group. Regarding administration time, no significant difference among three evaluation periods was observed (P > 0.05). Such results indicate that EEA did not exert mutagenic activity. Cytotoxicity was evident in doses of 50, 100 and 160 mg.kg-1 at 24 and 48 hours after exposure. Concerning antimutagenicity, except the 10 mg.kg-1 co-administered with 4 mg/kg of MMC, all doses reduced significantly the frequency of MNPCE compared to the positive control group (P < 0.05). These results, therefore, indicate an antimutagenic activity of the EEA. Cytotoxicity was significantly increased (P < 0.01) at 100 mg.kg-1 EEA doses co-administered with 4 mg.kg-1 of MMC.

O araticum (Annona crassiflora Mart.) é uma planta tipicamente brasileira, largamente utilizada em humanos como remédio para o tratamento de diversas doenças como diarréia, reumatismo e sífilis. Esta planta contém acetogeninas que apresentam propriedades citotóxica, antitumorigênica e antiparasitária. Neste estudo, foram avaliados os possíveis efeitos mutagênico, antimutagênico e citotóxico do extrato etanólico de folhas de araticum, pelo teste de micronúcleos em camundongos. Para a investigação da atividade mutagênica, os animais foram tratados com o extrato etanólico de araticum (EEA) utilizando 10, 20, 50, 100 e 160 mg.kg-1. Para todas as doses, as freqüências de eritrócidos policromáticos micronucleados (MNPCE) foram avaliadas em 24, 48 e 72 horas após o tratamento. Para a investigação da atividade antimutagênica, os animais foram tratados com 10, 20, 50 e 100 mg.kg-1 de EEA simultaneamente com 4 mg.kg-1 de MMC. A freqüência de MNPCE foi avaliada após 36 horas de exposição. A citotoxicidade foi avaliada pela razão de eritrócitos policromáticos e normocromáticos (PCE/NCE). Na avaliação da mutagenicidade, todas as doses de EEA não aumentaram significativamente o número de MNPCE (P > 0,05), comparativamente as do grupo solvente-controle. Em relação ao tempo de administração, não foi constatada diferença significativa entre os 3 períodos avaliados (P > 0,05). Esses resultados indicam que o EEA não exerceu atividade mutagênica.A citotoxicidade foi evidente nas doses de 50, 100 e 160 mg.kg-1 em 24 e 48 horas depois da exposição. Em relação à antimutagenicidade, exceto para a dose de 10 mg.kg-1 co-administrada com 4 mg.kg-1 de MMC, todas reduziram significativamente a freqüência de MNPCE, comparativamente as do grupo controle positivo (P < 0,05). Esses resultados, portanto, indicam uma atividade antimutagênica do EEA. A citotoxicidade foi significativamente aumentada (P < 0,01) na dose de 100 mg.kg-1 de EEA co-administrada com 4 mg.kg-1 de MMC.

Aluminium toxicity induced poikilocytosis in an air-breathing teleost, Clarias batrachus (Linn.).

The present study was undertaken to assess the toxicity of acid alone and two different sublethal concentrations of aluminium, (25% and 75% dose of 96 hr LC50 value in acidified soft water of pH 5) on red blood cells of a stenohaline catfish, C. batrachus for an acute exposure of 5 days. The scanning electron microscopic studies on all the three treated groups revealed several kinds of erythrocyte alterations and modifications with abnormal morphology. These included abnormal surface-wrinkling accompanied with excessive roughness on the membrane, erythrocytes with surface granulation in higher dose and finally the appearance of morphologically abnormal forms, the codocyte (target cell) and the stomatocyte. The results suggest that abnormality in the shape of erythrocytes could be linked to altered surface membrane area to volume ratio, decrease in cytoplasmic volume owing to reduced Hb content or increase in the amount of water content within the cell resulting from osmotic disequilibrium. In this context, the abnormal surface membrane morphology could be attributed to cytoskeleton fragility and defects in structural proteins. Further, the acid group exhibited a striking behavior of cellular adhesion and bonding to adjoining cell surfaces, culminating in several bunches which thereby reduces the surface area for gaseous exchange and could produce blocking effect while flowing through microcirculation.