[Assessment of disease activity of rheumatoid arthritis by ultrasonography].

Rheumatoid arthritis (RA) is a typical autoimmune disease of connective tissue, with the synovial joints as the main site of the disease. Bone erosion occurs in the initial stage. A key factor in treating and understanding the prognosis of the disease is to determine which stage of the lesion is caused by rheumatoid arthritis. In order to assess bone erosion and determine the degree of synovial proliferation, ultrasonography has come into the spotlight as a method of visualizing the rheumatoid arthritis lesion, which cannot be distinguished superficially from the cutaneous condition. Joint ultrasonography is a relatively inexpensive procedure that can be used to examine patients repeatedly; therefore, we can compare serial data from such patients. The joint lesion, which we focused on, can be understood in real time and is superior in many respects. However, at present, there are problems with examiner bias and the lack of a standard assessment method, because joint ultrasonography alone does not provide objective imaging findings. Now, joint ultrasonography is also useful as a supportive method to clarify mobility around the articular region. Ultrasonography might be used as a supportive method for the early diagnosis, assessment of disease activity, evaluation of the drug efficacy, prognosis, and as part of the differential diagnosis.

Novel technique for suspension culture of autologous chondrocytes improves cell proliferation and tissue architecture.

We have developed a new and simple method of chondrocyte suspension culture using a spinner bottle with rotation of the matrices. We compared the characteristics of chondrocytes cultured by this method with those grown in standard monolayer cultures. We also determined the optimal nutritional medium for suspension cultures. Periosteum explants seeded with chondrocytes were grown in monolayer and suspension cultures under three conditions: in medium with no additive (control), with 10% fetal bovine serum (FBS), or with 10% autologous serum (AS). After culturing, the explants were harvested, processed for histology, and stained with hematoxylin-eosin or TUNEL, or immunostained for type I, II, and III collagen, and Ki-67 antigen. In monolayer cultures, the attachment of the chondrocytes to the periosteum was weak and the superficial layer consisted of fibrotic tissue and few nucleated cells. Collagen type II staining was strong, but types I and II were weak. Among the suspension cultures the AS group produced the thickest layer of chondrocytes with the fewest apoptotic cells. The superficial layer of cartilage in these cultures stained positive for type I and III collagen and Ki-67 antigen. Among the suspension cultures, total chondroitin and chondroitin-4 sulfate (C-4S) concentration was highest in the AS group, while prostaglandin E2 (PGE2) was highest in the FBS group. In summary, our new method of suspension culture of periosteal explants using rotational matrices combined with AS nutritional media was the most effective method for maintaining the bond between the chondrocyte layer and periosteum, as well as the production of type I and III collagen in the superficial layer.