Browsing by Author "Dodoo, A.K."
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Item Cytokines and adhesion molecules expression in the brain in human cerebral malaria(International Journal of Environmental Research and Public Health, 2005) Armah, H.; Wired, E.K.; Dodoo, A.K.; Adjei, A.A.; Tettey, Y.; Gyasi, R.Although the role of systemic proinflammatory cytokines, IL-1beta and TNF-alpha, and their up-regulation of adhesion molecules, ICAM-1, VCAM-1 and E-Selectin, in the pathogenesis of cerebral malaria (CM) is well established, the role of local cytokine release remain unclear. Immunohistochemistry (IHC) was used to compare the expression of ICAM-1, VCAM-1, E-Selectin, IL-1beta, TNF-a and TGF-beta at light microscopic level in cerebral, cerebellar and brainstem postmortem cryostat sections from 10 CM, 5 severe malarial anemia (SMA), 1 purulent bacterial meningitis (PBM), 2 non-central nervous system infections (NCNSI) and 3 non-infections (NI) deaths in Ghanaian children. Fatal malaria and Salmonella sepsis showed significantly higher vascular expression of all 3 adhesion molecules, with highly significant co-localization with sequestration in the malaria cases. However, there was negligible difference between CM and SMA. TGF-beta showed intravascular and perivascular distribution in all cases, but expression was most intense in the PBM case and CM group. TNF-alpha and IL-1beta showed prominent brain parenchymal staining, in addition to intravascular and perivascular staining, in only the PBM case and CM group. The maximal expression of all 6 antigens studied was in the cerebellar sections of the malaria cases. Endothelial activation is a feature of fatal malaria and Salmonella sepsis, with adhesion molecule expression being highly correlated with sequestration. IL-1beta and TNF-alpha are upregulated in only cases with neurodegenerative lesions, whilst TGF-beta is present in all cases. Both cytokines and adhesion molecules were maximally upregulated in the cerebellar sections of the malaria cases.Item High-level cerebellar expression of cytokines and adhesion molecules in fatal, paediatric, cerebral malaria(Annals of Tropical Medicine and Parasitology, 2005) Armah, H.; Dodoo, A.K.; Wiredu, E.K.; Stiles, J.K.; Adjei, A.A.; Gyasi, R.K.; Tettey, Y.Although the roles played by systemic tumour necrosis factor (TNF) and interleukin 1beta (IL-1beta), and their upregulation of intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1) and E-selectin, in the pathogenesis of human cerebral malaria (CM) are well established, the role of local cytokine release, in the brain, remains unclear. Immunohistochemistry was therefore used to compare the expression of ICAM-1, VCAM-1, E-selectin, IL-1beta, TNF and transforming growth factor beta (TGF-beta) at light-microscope level, in cryostat sections of cerebral, cerebellar and brainstem tissues collected, post-mortem, from Ghanaian children. Among the 21 children investigated were 10 cases of CM, five of severe malarial anemia (SMA), one of purulent bacterial meningitis (PBM), two of non-central-nervous-system infection (NCNSI) and three children who had no infection (NI) when they died. Parasitised erythrocytes were detected in all of the sections from the cases of fatal malaria (CM and SMA), and sequestered leucocytes were present in most of the sections from the CM cases (but none of the sections from the SMA cases). Significantly elevated vascular expression of all three adhesion molecules investigated was detected in the brains of the 15 cases of fatal malaria and one of the cases of NCNSI (a child with Salmonella septicaemia), and in the malaria cases this showed highly significant co-localization with the areas of erythrocyte sequestration. In terms of the levels of expression of ICAM-1, VCAM-1 and E-selectin, there were, however, negligible differences between the CM and SMA cases. Although TGF-beta showed intravascular and perivascular distribution in all the subjects, its expression was most intense in the PBM case and the CM group. Only in the sections from the PBM and CM cases did TNF and IL-1beta show prominent brain parenchymal staining, in addition to the intravascular and perivascular staining seen in all subjects. The highest observed expression of each of the six antigens studied was in the cerebellar sections of the malaria cases. Endothelial activation in the brain therefore appears to be a feature of fatal malaria and Salmonella sepsis, and in cases of fatal malaria is closely associated with leucocyte sequestration. In the present study, IL-1beta and TNF were only up-regulated in the brains of children with neurodegenerative lesions, whereas TGF-beta was present in all cases.Item Immunolocalization of the 29 kDa Schistosoma haematobium species-specific antigen: a potential diagnostic marker for urinary schistosomiasis(BioMed Central Ltd., 2015) Markakpo, U.S.; Armah, G.E.; Fobil, J.N.; Asmah, R.H.; Anim-Baidoo, I.; Dodoo, A.K.; Madjitey, P.; Essuman, E.E.; Kojima, S.; Bosompem, K.M.BACKGROUND: The 29 kDa Schistosoma haematobium species-specific antigen (ShSSA) is of remarkable interest in the diagnosis of urinary schistosomiasis although it had not been fully characterized.METHOD: To determine the biological importance of ShSSA in S. haematobium and pathogenesis of the disease, we immunolocalized ShSSA in schistosome eggshells, miracidia and adult worm sections using indirect fluorescent antibody test (IFAT).RESULTS: ShSSA was strongly immunolocalized in the schistosome eggshells, selective regions of the miracidia body and walls of internal organs such as oviduct, ovary, vitelline duct and gut of the adult worm.CONCLUSION: The strong immunolocalization of ShSSA in schistosome eggshells and adult worm internal organs suggests that the antigens involved in the pathogenesis of urinary schistosomiasis could have originated from the eggs and adult worms of the parasite. The findings also indicate that ShSSA may play a mechanical protective role in the survival of the parasite.Item Immunolocalization of the 29 kDa Schistosoma haematobium species-specific antigen: A potential diagnostic marker for urinary schistosomiasis(BioMed Central Ltd., 2015) Markakpo, U.S.; Armah, G.E.; Fobil, J.N.; Asmah, R.H.; Anim-Baidoo, I.; Dodoo, A.K.; Madjitey, P.; Essuman, E.E.; Kojima, S.; Bosompem, K.M.Background: The 29 kDa Schistosoma haematobium species-specific antigen (ShSSA) is of remarkable interest in the diagnosis of urinary schistosomiasis although it had not been fully characterized. Method: To determine the biological importance of ShSSA in S. haematobium and pathogenesis of the disease, we immunolocalized ShSSA in schistosome eggshells, miracidia and adult worm sections using indirect fluorescent antibody test (IFAT). Results: ShSSA was strongly immunolocalized in the schistosome eggshells, selective regions of the miracidia body and walls of internal organs such as oviduct, ovary, vitelline duct and gut of the adult worm. Conclusion: The strong immunolocalization of ShSSA in schistosome eggshells and adult worm internal organs suggests that the antigens involved in the pathogenesis of urinary schistosomiasis could have originated from the eggs and adult worms of the parasite.Item Seasonality of rotavirus infection in Ghana.(Annals of Tropical Paediatrics, 1994) Armah, G.E.; Mingle, J.A.A.; Dodoo, A.K.; Anyanful, A.; Antwi, R.; Commey, J.; Nkrumah, F.K.Human rotavirus (HRV) infection and its seasonal distribution was studied over a 12-month period in Ghana. A total of 561 stool samples, 447 diarrhoea stools and 114 non-diarrhoea stools (controls), were obtained from children attending three polyclinics in Accra. Rotavirus was detected during 10 of the 12 months and showed a seasonal trend. It was high during the relatively cool dry months and low during the wet season. Peaks of infection were in February (26.2%) and September (24.5%). HRV was detected in 67 of 447 of the diarrhoea stools (15.0%) and in eight of 114 controls (7.0%). The HRV isolation rate was highest (20.2%) in the under-18-months age group