No abstract

Although young mice homozygous for the osteopetrosis (op) mutation usually developed prominent osteopetrosis, its severity was markedly reduced in aged op/op mice. This age-associated reversal of osteopetrosis was accompanied by the expansion of bone marrow cavities and increased numbers of tartrate-resistant acid phosphatase (TRAP)-positive cells and of macrophages in the bone marrow. The TRAP-positive cells were mononuclear and developed ruffled borders and numerous vesicles, vacuoles, and granules. Enzyme-linked immunosorbent assay demonstrated a significant elevation of serum granulocyte/ macrophage colony-stimulating factor (GM-CSF) and interleukin (IL)-3 levels in the aged op/op mice. To examine whether GM-CSF and/or IL-3 could correct osteopetrosis in young op/op mice, 5 ng of recombinant murine (rm)GM-CSF and/or 100 ng of rmIL-3 were injected daily into young op/op mice. In these treated young op/op mice, the bone marrow cavities were expanded significantly at 2 weeks after administration, associated with significantly increased numbers of TRAP-positive cells and bone marrow macrophages. TRAP-positive cells increased in number with days after injection. These results suggest that GM-CSF and IL-3 induce the development of osteoclasts to correct osteopetrosis in the op/op mice with aging.

G12 rotaviruses are emerging rotavirus strains causing severe diarrhea in infants and young children worldwide. However, the whole genomes of only a few G12 strains have been fully sequenced and analyzed. In this study, we sequenced and characterized the complete genomes of six G12 strains (RVA/Human-tc/MMR/A14/2011/G12P[8], RVA/Human-tc/MMR/A23/2011/G12P[6], RVA/Human-tc/MMR/A25/2011/G12P[8], RVA/Human-tc/MMR/P02/2011/G12P[8], RVA/Human-tc/MMR/P39/2011/G12P[8], and RVA/Human-tc/MMR/P43/2011/G12P[8]) detected in six stool samples from children with acute gastroenteritis in Myanmar. On whole genomic analysis, all six Myanmarese G12 strains were found to have a Wa-like genetic backbone: G12-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1 for strains A14, A25, P02, P39, and P43, and G12-P[6]-I1-R1-C1-M1-A1-N1-T1-E1-H1 for strain A23. Phylogenetic analysis showed that most genes of the six strains examined in this study were genetically related to globally circulating human G1, G3, G9, and G12 strains. Of note is that the NSP4 gene of strain A23 exhibited the closest relationship with the cognate genes of human-like bovine strains as well as human strains, suggesting the occurrence of reassortment between human and bovine strains. Furthermore, strains A14, A25, P02, P39, and P43 were very closely related to one another in all the 11 gene segments, indicating derivation of the five strains from a common origin. On the other hand, strain A23 consistently formed distinct clusters as to all the 11 gene segments, indicating a distinct origin of strain A23 from that of strains A14, A25, P02, P39, and P43. To our knowledge, this is the first report on whole genome-based characterization of G12 strains that have emerged in Myanmar. Our observations will provide important insights into the evolutionary dynamics of spreading G12 rotaviruses in Asia.

In 2007 and 2008 in Myanmar, we detected influenza viruses A (H3N2) that exhibited reduced sensitivity to both zanamivir and amantadine. These rare and naturally occurring viruses harbored a novel Q136K mutation in neuraminidase and S31N mutation in M2.

Epidemiologic and molecular investigations of Hodgkin's disease (HD) suggest a strong infectious association. The Epstein-Barr virus (EBV), together with its viral proteins, is expressed in Hodgkin-Reed-Sternberg (HRS) cells in the lymph nodes involved by HD. EBV is more likely to be related to childhood and older adult cases of HD and is much less frequently expressed in young adult HD patients, the group most expected to be associated with an infectious agent. In addition, the "hit and run" theory of EBV infection remains speculative and no other lymphotropic viruses studied to date seem to satisfy the quest for a new candidate virus in young adults with HD. We have recently found preliminary evidence suggesting a possible association between the measles virus (MV) and HD. This evidence is the subject of the present review.