Kensuke Yonemura

Deposition of calcium pyrophosphate dihydrate crystals in the hand

A rare case with deposition of calcium pyrophosphate dihydrate crystals around the proximal portion of the first and second metacarpal bones is reported. The second metacarpal had a cystic lesion, and the cortex of the first metacarpal had irregular osteolytic change. There were degenerative changes in the first carpometacarpal joint, trapeziotrapezoid articulation, and second carpometacarpal joint. The patient had recurrent acute inflammatory attacks at the affected site. Initially the patient was thought to have tumoral calcinosis, or a calcifying soft-tissue tumor, with the possibility of a malignant tumor because of angiographic evidence of tumor stain and hypervascularity. Surgical biopsy with partial curettage of the calcified mass resulted in early recurrence of deposition of the crystals. Total excision would seem to be necessary to avoid recurrence.

Inhibitory Effect of 1‐β‐D‐Arabinofuranosylthymine on Synthesis of Epstein‐Barr Virus

The effect of 1‐β‐d‐arabinofuranosylthymine (ara‐T) on cell growth and synthesis of Epstein‐Barr virus (EBV) in human lymphoblastoid cell lines was determined. The growth of P3HR‐1 cells was not inhibited by 1 μg of the drug per ml; however, infectious virus production was strongly inhibited and was accompanied by decreased expression of early antigen (EA) and viral capsid antigen (VCA). The ability of 12‐O‐tetradecanoylphorbol‐13‐acetate or n‐butyric acid to induce synthesis of VCA, but not EA, in P3HR‐1 cells was inhibited by ara‐T. Similarly, VCA synthesis but not EA synthesis was inhibited by ara‐T in Jijoye cells superinfected with the P3HR‐1 strain of EBV. The results suggest that ara‐T has a specific inhibitory action against EBV replication.

Antitumor effects of adriamycin encapsulated in liposomes on chemically induced malignant fibrous histiocytoma in rats: Histological aspects*

We previously reported that, in an experimental animal model (rat), the in vivo growth of chemically induced malignant fibrous histiocytoma (MFH) was inhibited more effectively by adriamycin encapsulated in liposomes (LADM) than by free adriamycin (ADM). To elucidate the histological changes caused by LADM administration, we compared LADM-treated tumor tissues with free ADM-treated tissues. A suspension of chemically induced rat MFH cells was injected subcutaneously into syngeneic rats. After a tumor had developed, free ADM or LADM was administered intravenously. The tumor tissues were then examined histologically. Microscopic examination showed that the number of small round infiltrated cells was greater in the LADM group than in the ADM group. Additionally, an immunohistochemical study with anti-rat lymphocyte or anti-rat macrophage monoclonal antibodies demonstrated that the significant decrease in W3/25+ cells observed in the control and ADM groups was not apparent in the LADM group, and that the percent-ages of cells positive for OX-8, ED2, and ED3 were significantly higher than in the ADM group. These histological changes seem to correlate closely with the inhibition of tumor growth. Our results suggest that LADM possesses the drug-carrying characteristic of liposomes and may also augment certain host defenses against rat MFH, just as biological response modifers do.

Infiltrating lipoma - A clinical study of 10 cases.

Infiltrating lipoma is characteristic in its infiltrative growth pattern and its frequency of local recurrence in spite of the benignancy. It involves the intermuscular and intramuscular types.We evaluated 10 cases with infiltrating lipoma. Five cases were intermuscular and the other 5 were intramuscular type. The age of patients ranged from 1 to 69 years old (mean age: 47.7 years old). The majority of the tumor was sited in the extremities, especially in the upper extremities. No recurrence was seen in all cases. The utility in imaging techniques such as CT or MRI was remarkable for the clarification of localization and even diagnosis of this tumor.Wide resection must be recommended to prevent the local recurrence, especially in the intramuscular type.