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Cerebral ischaemia usually results in the rapid death of neurons within the immediate territory of the affected artery. Neuronal loss is accompanied by a sequence of events, including brain oedema, blood–brain barrier (BBB) breakdown, and neuroinflammation, all of which contribute to further neuronal death. Although the role of macrophages and mononuclear phagocytes in the expansion of ischaemic injury has been widely studied, the relative contribution of these cells, either of exogenous or intrinsic central nervous system (CNS) origin is still not entirely clear. The purpose of this study, therefore, was to use different durations of transient middle cerebral artery occlusion (tMCAo) in the mouse to investigate fully post-occlusion BBB permeability and cellular changes in the brain during the 72 h post-MCAo period. This was achieved using in vivo magnetic resonance imaging (MRI) and cell labelling techniques. Our results show that BBB breakdown and formation of the primary ischaemic damage after tMCAo is not associated with significant infiltration of neutrophils, although more are observed with longer periods of MCAo. In addition, we observe very few infiltrating exogenous macrophages over a 72 h period after 30 or 60 mins of occlusion, instead a profound increase in proliferating resident microglia cells was observed. Interestingly, the more severe injury associated with 60 mins of MCAo leads to a markedly reduced proliferation of resident microglial cells, suggesting that these cells may play a protective function, possibly through phagocytosis of infiltrating neutrophils. These data further support possible beneficial actions of microglial cells in the injured brain.Journal of Cerebral Blood Flow & Metabolism (2007) 27, 1941–1953; doi:10.1038/sj.jcbfm.9600495; published online 18 April 2007 [ABSTRACT FROM AUTHOR]

Abstract: Objective.: Typically, human ovarian cancer is widely disseminated at the time of diagnosis and shows extremely poor prognosis. Experimental animal models that mimic human ovarian cancer are often incomplete when compared to the full spectrum of the human disease with regard to its histological hallmarks such as the spread of carcinoma, its ability to seed the peritoneal cavity and formation of ascites. We have established and characterized a new animal model for human ovarian cancer in nude mouse. Methods.: A new cell line SKOV-3m was injected intraperitoneally in nude mice. Mice were divided in two groups A and B, which received 1×107 and 2×107 cells, respectively. Histology, immunohistochemistry, magnetic resonance imaging and ultrasound were used to analyze tumors. Results.: All mice had tumors within 18 days and histologically they resembled poorly differentiated human cystadenocarcinomas with bloody ascites. Mean survival of the mice was 42±14 and 21±2 days in groups A and B, respectively. Magnetic resonance imaging and ultrasound were used to confirm the presence of tumors and to monitor their growth without sacrificing the animals. Conclusion.: This new xenograft model accompanied by noninvasive imaging is highly reproducible and likely to be very useful in testing new treatment strategies for ovarian cancer. [Copyright &y& Elsevier]