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T Sasho

Publications and source records attributed to T Sasho.

5 recordsLinked to original sources

Chondroprotective activity of N-acetylglucosamine in rabbits with experimental osteoarthritis.

OBJECTIVE: To examine the therapeutic efficacy of N-acetylglucosamine (GlcNAc) in rabbits with experimental osteoarthritis (OA). METHODS: Experimental OA was induced in rabbits by anterior cruciate ligament transection (ACLT). In the first study, rabbits (six in each group) received intramuscular injections of GlcNAc or normal saline three times a week starting 1 week postoperatively. In the second study, rabbits (eight in each group) were injected intra-articularly with GlcNAc (either once or twice a week) or normal saline. In the third study, rabbits (seven in each group) were injected intra-articularly twice a week with either GlcNAc, hyaluronan, or normal saline. Animals were killed 8 weeks after ACLT for macroscopic and histological assessment of the knee joints. RESULTS: Intramuscular administration of GlcNAc in rabbits with experimental knee OA did not show chondroprotective effects but showed mild anti-inflammatory activity. In contrast, intra-articular administration of GlcNAc twice a week reduced cartilage degradation. Additionally, intra-articular GlcNAc also suppressed synovitis. Once a week intra-articular injections of GlcNAc did not demonstrate therapeutic efficacy. The chondroprotective efficacy of GlcNAc was better than that of viscosupplementation treatment with hyaluronan. CONCLUSION: Intra-articular GlcNAc has chondroprotective and anti-inflammatory activity in experimental OA.

Acetylglucosamine↗

Extrathymic development of V alpha 11 T cells in placenta during pregnancy and their possible physiological role.

The molecular and cellular mechanisms of the feto-maternal immune responses in the placenta in connection with natural abortion remain unclear. In this report we provide evidence that V(alpha11) T cells developed in the placenta may be responsible for the induction of natural abortion. The majority of V(alpha11) TCRs detected during pregnancy showed a consensus motif in the CDR3 region, similar to that of anti-GM3 TCR clones, and were of maternal origin. V(alpha11) TCRs were found in the middle to late stages of gestation due to de novo generation in the placenta, not to migration from the maternal side, as evidenced by the significant increases in the out-of-frame V(alpha11) TCR mRNA and the copy number of circular DNA generated by V(alpha11) gene rearrangements. Furthermore, administration of anti-V(alpha11) Ab to pregnant mice resulted in a significant decrease in the incidence of fetal demise, suggesting that V(alpha11) T cells detected in the placenta develop extrathymically and are involved in natural abortion.

Animals↗

Extrathymic development of V alpha 14-positive T cells.

It is known that rearrangement of the T cell antigen receptor (TCR) gene occurs in the thymus during T cell development and consequently results both in the deletion of DNA between the variable (V) and diversity/joining segments and in the formation of a circular DNA with recombination signal sequences. Here, we provide evidence that V alpha 14+ TCR gene rearrangements take place in extrathymic sites, such as bone marrow, liver, and intestine, but not in spleen, because we were able to detect frequent productive and nonproductive V alpha 14+ coding and signal sequences as a result of TCR rearrangements in extrathymic sites. Similar findings were also detected in athymic mice. Quantitative analysis shows that the relative amounts of V alpha 14 gene-mediated signal sequences in extrathymic tissues are higher than those in thymus. On the contrary, TCR rearrangements of V alpha 1.1 T cells, which are known to develop in the thymus, were mainly detected in the thymus, Peyer's patch, and spleen, but not in other extrathymic tissues, showing patterns distinct from V alpha 14 TCR rearrangements. These findings are evidence of extrathymic development of V alpha 14+ T cells. Differential characteristic TCR rearrangement patterns also indicate that distinct TCR repertoires are generated in different lymphoid tissues.

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