Hiroshi Ohami

Evaluation of omental implantation for perforated gastric ulcer therapy: Findings in a rat model

Omental implantation, a surgical procedure in which a perforated gastric or duodenal ulcer is repaired by drawing and implanting a portion of the omentum into the digestive tract, accelerates ulcer healing and inhibits ulcer recurrence. However, the mechanisms underlying these beneficial effects are largely unknown. To clarify these mechanisms, we investigated ulcer healing in two groups of rats in which acetic acid-induced gastric ulcers were perforated. Omental implantation was used for repair in one group and simple suturing was employed in the other group. Greater antiinflammatory and angiogenic activity and accelerated collagen synthesis were seen in the omental implantation group. Basic fibroblast growth factor (bFGF)-mediated angiogenesis was noted in this group, as well as transforming growth factor-β1 (TGF-β1) activity within and around the omentum, resulting in abundant collagen production. It was confirmed that omental implantation accelerated ulcer healing and inhibited ulcer recurrence, and the presence of bFGF and TGF-β1 played a significant role in both these phenomena.

Early adrenal infection by herpes simplex virus type-1 (Miyama + GC strain): special reference to inoculation dose and spread from the adrenal to the central nervous system.

SummaryMale C3H/HeN mice, aged 5 weeks, were inoculated intraperitoneally (i.p.) with different doses (1 × 103, 1 × 105, 5 × 105, 1 × 106 pfu) of the herpes simplex virus type-1 (HSV-1) (Miyama+ GC strain). The LD50 of this virus was 102 pfu (i.p.) per mouse. All the mice in each group died 12 days after inoculation. Adrenal necrosis was found to be dose-dependent, the threshold dose being 5 × 105 pfu. In addition, encephalitis and inflammatory cell infiltration in abdominal ganglia appeared in 3–4 days after inoculation. By the plaque method, HSV-1 was detected first in the adrenal glands, then in neurons in the spinal cord and the brain. These findings suggest that in mice inoculated with doses of virus sufficient to infect the adrenal gland, HSV-1 spreads to the central nervous system through peripheral nerves after replication in the adrenal.

Establishment and characterization of a fibrous histiocytoma cell line (NMSG 10) derived from a malignant fibrous histiocytoma

A fibrous histiocytoma cell line, NMSG 10, was derived from a malignant fibrous histiocytoma (MFH), of human tibia, and its characteristics were examined. MFH was a pleomorphic subtype associated with myxoid and storiform areas. Primary culture revealed a mixture of histiocyte-like cells, fibroblast-like cells and giant cells, but fibroblast-like cells became the major population after several passages in vitro. In addition, NMSG 10 produced a large amount of viscous material which stained with alcian blue and was digested by hyaluronidase. Thus, this viscous material was a single component of glycosaminoglycans: hyaluronic acid (HA). The cells were spindle-shaped with well-developed cytoplasmic organelles and collagenous filaments, and a colloid iron-positive substance was observed in intercellular spaces. In scid mice, the mixed populations of neoplastic cells appeared similar in histology to that of the original tumor. These findings indicated that NMSG 10 expresses the unique properties of MFH, and should therefore be useful in studies on the biological behavior, and especially the presence of HA in MFH.

ULTRASTRUCTURAL LOCALIZATION OF THOROTRAST (THORIUM DIOXIDE) IN HUMAN LIVER BY ANALYTICAL SCANNING ELECTRON MICROSCOPE

The distribution of thorium dioxide (Thorotrast) in the liver from a Thorotrast‐administered autopsy case was examined stereographically by analytical scanning electron microscopy. Thorium particles were detected in the macrophages of the portal triad and hepatic sinusoid. These macrophages were irregularly shaped and tended to be aggregated. In the sinusoid, accumulation of the macrophages formed a thrombus‐like structure. Furthermore, observed in the sinusoid were free Thorotrast particles that appeared to have been released into the sinusoid as a result of breakdown of the macrophages (Kupffer cells).