Mesenchymal stem cells (MSCs) are well known to possess multipotential differentiation and are becoming a good tool for clinical research. However, specific markers for their purification and the mechanism of their osteogenic differentiation remain to be elucidated. In the present study, we compared the expression of CD106, and osteogenic differentiation-related proteins and genes in human bone marrow (BM)-derived MSCs, before and after differentiation by FACS, histochemical staining, immunohistochemical staining, RT-PCR, and real-time PCR. It was found that MSCs were positive for CD13, CD29, CD44, CD73, CD90, CD105, and CD166, but negative for CD14, CD31, CD34, CD62E, CD45, and GlyA. Notably, CD106 was detected before osteogenic induction, but its expression was downregulated 10 fold after 2 weeks of osteogenic differentiation as determined by flow cytometry. The results of RT-PCR and real-time PCR revealed that the expression of CD106 mRNA in MSCs significantly decreased by 7.1-, 4.2-, and 5.1-fold, respectively after osteogenic, chondrogenic, and adipogenic differentiation. In contrast, other MSC-positive markers described above did not change significantly even after differentiation. Compared to levels in control cells, after 2 weeks of osteogenic differentiation, mRNA levels of alkaline phosphatase, bone sialoprotein, osteocalcin, and transcript factors RUNX2 and Osterix showed more than 2-fold, 5-fold, 1.5-fold, 2-fold, and 5-fold increase, respectively. Thus, we speculate that CD106 might be a useful surface marker for BMMSCs. Moreover, alkaline phosphatase, type I collagen, osteonectin, osteopontin, and biglycin were expressed in the early stages of osteogenic differentiation before bone sialoprotein and osteocalcin. The present study should help to provide a novel marker for isolating purified MSCs and characterizing osteogenic differentiation.

Preparation of human immune T cells containing iron-oxide nanoparticles was carried out for the development of magnetically mediated immunotherapy. Peripheral blood lymphocytes (PBLs) after the incubation with magnetite nanoparticles were found to contain measurable ferric ions, which suggested the incorporation of magnetite nanoparticles. Transmission electron microscopic (TEM) study indicated that the incorporation of magnetite nanoparticles was mediated by endocytosis of PBLs. Furthermore, the effects of dosages and diameter of magnetite nanoparticles on the magnetite incorporation were investigated, and it was demonstrated that the increase in dosage promoted the incorporation of nanoparticles and the uptake into PBLs was more effective for magnetite nanoparticles, which formed smaller aggregations in medium. Finally, the demonstration of magnetite incorporation into enriched T cells and tumor antigen-specific cytotoxic T lymphocyte (CTL) line promises the achievement of magnetically mediated immunotherapy with tumor-specific CTLs containing magnetic nanoparticles.

Several kinds of middle cerebral artery occlusion model in rats have been developed. Variable ischemic inductions are attributed to the different contributing factors in ischemic damage formation. In the present study, we examined the differences in ischemic induction attributed to chronic stage. Male Sprague-Dawley rats were subjected to two kinds of middle cerebral artery occlusion model, a thermocoagulation and a photothrombosis model. We compared the changes in body weight, neurological outcome, size of ischemic damage, brain edema and atrophy formation, and histological data for 84 days between a thermocoagulation and a photothrombosis model in rats. Although the time courses of infarction formation were no different, there were differences in the time courses of brain edema, atrophy formation, and neuronal deficits between the models. Microinfarction formation was observed as a characteristic of the photothrombosis model. The present study demonstrated that differences in ischemic induction did not affect maturation of infarct size, brain atrophy, or neuronal deficits 84 days after ischemia. However, the progress of maturation was different between the models. The possibility that reperfusion contributed to the time course of brain edema and atrophy was considered, and it was suggested that brain edema formation influenced neurological outcome.

We report two cases of a large-cell neuroendocrine carcinoma of the skin as a distinct histological category. The patients are a 63-year-old woman with a 7-mm reddish round nodule on her nose for 4 months, and a 95-year-old man with several hemorrhagic nodules on the external ear for 28 months. The first patient had two positive sentinel lymph nodes. The tumors from both patients consisted of islands of pleomorphic large cells within a lymphoid stroma.