Nuclear ultrastructure in low and high grade Non-Hodgkin's Lymphomas

Transmission electron microscopy was used to study the ultrastructure of nucleoli in 3 high and 3 low grade non-Hodgkin's lymphomas. Nucleoli with a single large fibrillar center were predominantly seen in the low grade group. While, the majority of nucleoli in high grade lesions contained several small fibrillar centers of approximately equal size. A third type of nucleolus appearance was identified with a large central fibrillar center surrounded by numerous small "satellite" fibrillar center. This nucleolus configuration was the least common but was more often seen in low grade than in high grade lymphomas. These results showed that fibrillar center size and morphology correlates with grade of non-Hodgkin's lymphoma and may reflect differences in ribosomal deoxyribonucleic acid transcription

Immunophenotyping of T-lymphocyte subsets in hepatic schistosomiasis with or without hepatitis B virus infection

Chronic human infection with Schistosoma mansoni trematodes is associated with impaired cell immunity. Granuloma formation and its modulation represent a delicate balance between T lymphocyte subsets, T helper and T suppressor cells. The lymphocytes identified were of pan T cell type CDT3 and showed marked CDT4 cells [helper/inducer] than CDT8 cells in granuloma formation and its modulation. The study showed a significant correlation between the degree of fibrosis and T helper cell levels which implies the role of the T helper pathogenesis of hepatic fibrosis. There was no significant difference between pure schistosomal group and the mixed one as regard T-lymphocyte subsets. It seems that the immunological events in both diseases were different