Histology and histopathology Vol.20, nº 4 (2005)
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- PublicationOpen AccessThe effect of the flavonoid diosmin, grape seed extract and red wine on the pulmonary metastatic B16F10 melanoma(Murcia : F. Hernández, 2005) Martínez, C.; Vicente García, Vicente; Yáñez, J.; Alcaraz, M.; Castells Mora, María Teresa; Canteras, M.; Benavente-García García, Obdulio; Castillo, J.Objective: To study the effect of different phenolic compounds and red wine on pulmonary metastatic melanoma. Methods: Swiss mice were inoculated with 5x105 melanocytes B16F10 and given oral doses of diosmin, grape seed extract (GSE) and red wine. A macroscopic count was made of the metastatic nodules on the lung surface and a microscopic study by image analysis of five sections, calculating the implantation percentage and tumoral growth and invasion indices. Results: Macroscopically, the group treated with diosmin showed the greatest reduction (52%) in the number of metastatic nodules compared with the control group, which was treated with ethanol, while GSE and red wine caused decreases of 26.07 and 28.81%, respectively. Microscopically, there was a decrease in the implantation percentage after the administration of diosmin (79.4%) and red wine (20.19%), and an increase of 2.12% after the administration of GSE, all relative to the ethanol-treated control. As regards the growth index, diosmin produced a reduction of 67.44% and red wine a reduction of 20.62%, while GSE again produced an increase (25.33%). The reductions in the invasion index were 45.23, 31.65 and 17.57% with diosmin, GSE and red wine, respectively. Conclusions: Diosmin originated the greatest reduction in pulmonary metastases, both at the macroscopic and microscopic levels.
- PublicationOpen AccessIs mitotic chromatid segregation random?(Murcia : F. Hernández, 2005) Bell, C.D.The question of whether mitotic segregation of chromatids is random or programmed assumes great significance for cellular differentiation if one recognizes that sister chromatids may have epigenetic differences and carry them from one generation into the next. The literature was examined for evidence of nonrandom chromosomal and chromatid segregation. Many organisms were described as undergoing non-random homologue segregation in meiosis I. The explanations for these phenomena were attributed in some instances, to peculiarities of the meiotic spindle, though in some convincing experiments, the epigenetic heterochromatin of the kinetochores was implicated. The few existing descriptions of non-random mitotic segregation were also described. Existing literature on ultrastructural, immunohistochemical, and physiological features of the chromatid kinetochores during the mitotic process was searched for evidence of asymmetry or structural differences between sister chromatids, which is presented. Also reported are descriptions of how epigenetic changes and cell differentiation can influence centromeric function and ultimately, kinetochore function. Fundamental to the hypothesis of gene regulation presented here, is the assumption that genetic foci on different chromosomes interact, and must be proximate to each other and stereologically compatible for interactions to occur. Also described are spatial changes in chromosomal territories associated with function and differentiation. These territories can be in varying nuclear locations depending on gene function, and may show asymmetry between daughter cells. Despite evidence presented for the possibility of non-random chromatid segregation at mitosis, this question will remain unanswered until the matter is specifically addressed by experiment.
- PublicationOpen AccessAnagrelide does not exert a myelodysplastic effect on megakaryopoiesis: a comparative immunohistochemical and morphometric study with hydroxyurea(Murcia : F. Hernández, 2005) Thiele, J.; Kvasnicka, H.M.; Ollig, S.; Schmitt-Gräff, A.A comparative immunohistochemical and morphometric study was performed on megakaryocytes in 20 patients presenting with initial-early stage chronic idiopathic myelofibrosis and accompanying thrombocythemia to elucidate histological features developing after hydroxyurea (HU) versus anagrelide (ANA) therapy. Representative pre-and posttreatment bone marrow biopsies were involved including the monoclonal antibody CD61 for the identification of precursor and mature stages of megakaryopoiesis. An elaborate morphometric evaluation was in keeping with a left-shifting showing a more frequent occurrence of promegakaryoblasts and microforms in both therapy groups. However, contrasting ANA, HU generated defects of differentiation consistent with significant dysplastic changes. In conclusion, concern about a possible leukemogenic capacity following long-term HU therapy is supported by our findings.
- PublicationOpen AccessCox and mesothelioma: an overview(Murcia : F. Hernández, 2005) Cardillo, I.; Spugnini, E.P.; Verdina, A.; Galati, R.; Citro, G.; Baldi, A.Cyclooxygenases catalyze the rate limiting step in the production of prostanoids. Accumulating data demonstrate that overexpression of these enzymes, and in particular of cyclooxygenases-2, promotes multiple events involved in tumorigenesis; in addition, numerous studies show that inhibition of cyclooxygenases-2 can delay or prevent certain forms of cancer. Malignant mesothelioma is a lethal pleural, peritoneal and pericardial neoplasia that actually lacks valid therapies and in which cyclooxygenases-2 is recognized as an important adverse prognostic factor. Hence, there is an increasing interest in the development of new treatments based on cyclooxygenases-2 inhibitors, to prolong survival and even potentially cure this neoplasia.
- PublicationOpen AccessTime course variations of antioxidant enzyme activities and histopathology of gilthead seabream gills exposed to malathion(Murcia : F. Hernández, 2005) Rosety, M.A.; Rosety-Rodriguez, M.; Ordóñez Muñoz, F.J.; Rosety, I.In a widely distributed and commercially important fish, gilthead seabream Sparus aurata L., we have studied sublethal effects of malathion in order to identify early warning bioindicators of exposure before irreversible damage occurs. To achieve this goal, groups of 10 juvenile specimens were exposed for 24, 48, 72 and 96h to a sublethal concentration of malathion (0.4 mg/l). Another group was used as control. The activity of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) and histopathological features from exposed gills were assessed. It should also be mentioned that no mortality was observed during the whole experience. The activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) were altered significantly from 24 h onward (p<0.05). It is of interest to note that catalase activity was decreased after exposure instead of increasing as other antioxidant enzymes assessed. On the other hand, histopathological alterations of the gills were observed as early as at 48 hexposure, but the most severe damage occurred at 96 h exposure. The evidence presented here, together with other data from the literature, unequivocally established oxidative-stress-inducing effects of malathion in gilthead seabream Sparus aurata. It is also concluded antioxidants employed (SOD, CAT and GPX) changed significantly a long time before histopathological alterations of gills became evident. Consequently, these antioxidant enzymes may be highly recommended as early-warning bioindicators of environmental pollution by malathion in the areas where it is proposed to be used in pest control activities.