We attempted to rescue supralethally irradiated (SLI) mice by transplantation of hematopoietic stem cells (HSCs) plus thymus from variously aged donors (fetus, newborn and adult). Although the transplantations of these kinds of HSCs alone showed a very short survival, newborn liver cells (NLCs) (as the source of HSCs) plus newborn thymus (NT) transplantation markedly improved the survival rate. The transplantation attenuated severe damage in the small intestine, which is one of the major causes of death by SLI. In addition, the donor-derived CD4 þ T cells significantly increased with additional NT transplantation. The production of interleukin (IL)-7 and keratinocyte growth factor, which plays a crucial role in protection against radiation injury in the intestine, was the highest in NT. Finally, SLI mice that had received NLC plus IL-7 À/À NT transplantation plus IL-7 injection showed improved survival, weight recovery and an elevated number of CD4 þ T cells compared with the mice that had received NLC plus IL-7 À/À NT or plus IL-7 injection alone. These findings suggest that NLCs plus NT transplantation can rescue SLI mice most effectively, and that high production of IL-7 in NT plays a crucial role with induction of CD4 þ T cells.

Summary MRL/lpr mice (H-2k ) with Fas gene mutation develop severe autoimmune diseases, and their haematolymphoid cells such as bone marrow and spleen cells showed a low apoptotic activity by irradiation. Therefore, conventional bone marrow transplantation (BMT) cannot be used to treat autoimmune diseases in these mice (chimeric resistance). In the present study, we examine the effects of additional adult thymus transplantation (

Spontaneous spinal epidural hematoma (SSEH) is rare. Its etiology remains controversial; however, spinal venous wall susceptibility to intravenous pressure change and the resultant venous rupture seem to be involved. The authors report a case of SSEH dorsal to the spine producing acute anterior spinal cord syndrome. A posterior SSEH between the C-3 and T-5 levels caused progressive tetraparesis and the disappearance of superficial body sensation below the level of C-8, although deep sensation remained completely intact. This neurological false localizing sign seems to have resulted from counterforce by preexisting asymptomatic cervical intervertebral disc herniation at the C6–7 levels inducing direct pressure on the anterior spinal cord. This case is the first reported instance of posterior cervical SSEH manifesting acute anterior spinal cord syndrome as its false localizing sign.

It has been reported that there is an inverse correlation between the immunohistochemical expression of Rb2/p130, a member of the retinoblastoma gene family, and the degree of malignancy in at least some histological types. In order to investigate the expression of this protein in gliomas, we evaluated 58 samples from patients with resected gliomas. We focused on the relationship between the degree of malignancy of the glioma and the immunohistochemical detection of Rb2/p130. Expression of Rb2/p130 was observed in 38 glioma specimens (65.5%), including a high expression level in low-grade glioma specimens (> 30% positive cells in 84% of tumors) and a low expression level in high-grade glioma specimens (> 30% positive cells in 12% of tumors). The most aggressive of the gliomas exhibited very low to undetectable levels of Rb2/p130. Moreover, we observed an inverse correlation between Rb2/p130 expression and the degree of malignancy. These findings suggest that the differentiation of gliomas might be partially mediated by the Rb2/p130 gene, and that Rb2/ p130 expression can additionally be an indicator of a better prognosis in patients with gliomas.

We report a rare case in which a myxoid chondrosarcoma originated from the petrous bone and invaded the cerebellar hemisphere with hemorrhage. Neuroimaging showed the characteristic feature of multiple small cysts along the solid tumor, and the cystic formation was confirmed as a mucoid secretion by Alcian blue staining and electron microscopic examination. This tumor recurred following partial removal and stereotaxic radiosurgery.