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Adult bone marrow cells (BMCs) include two populations:;mesenchymal stem cells (MSCs), which can differentiate into bone, cartilage, and fat; and hematopoietic stem cells (HSCs), which produce all mature blood lineage. To study the effect of aging, gender, and age-related disorders on lineage differentiation, we performed quantitative RT-PCR to examine mRNA expression of the major factors defining BMC lineage, cbfa1 for osteoblasts, ppar-gamma for adipocytes, sox9 for chondrocytes, and rankl for osteoclasts, in bone marrow from 80 healthy subjects and patients (14-79 years old) with two age-related disorders: osteoarthritis (OA) and rheumatoid arthritis (RA). Two apoptosis-related genes, bcl-2 and drak1, were studied. RANKL and PPAR-Gamma levels exhibited a clear positive correlation with age in female patients, but not in males, with a slight age-related decline in CBFa1 transcripts. DRAK1 expression showed an age-associated ascending trend with significantly greater transcripts of RANKL and DRAK1 in females (p < 0.01). Compared with age-matched controls, RA patients exhibited increased RANKL, PPAR-Gamma, and DRAK1 mRNA levels (p < 0.05), and OA showed the higher RANKL and PPAR-Gamma transcripts (p < 0.05). Furthermore, SOX9 and DRAK1 expressions in the RA group were higher than in the OA group (p < 0.05). Our data indicate that aging and age-related disorders affect gene expressions differently, suggesting that in aging, the lineage of bone marrow cells was modified with prominent changes in decreased bone marrow osteoblastogenesis, increased adipogenesis and osteoclastogenesis, while in age-related disorders, marrow adipogenesis and the activity or number of osteoclasts may play an important role in the pathogenesis of arthritic bone loss.

Our objective was to examine the technique of regenerating cartilage tissue from bone marrow-derived cells by three-dimensional (3D) culture using the rotating wall vessel (RWV) bioreactor. Three-dimensional and cylindrical aggregates of allogeneic cartilage with dimensions of 10 x 5 mm (height x diameter) formed by the RWV bioreactor were transplanted into osteochondral defects of Japanese white rabbits (Group T, n = 15). For the control, some osteochondral defects were left empty (Group C, n = 18). At 4, 8, and 12 weeks postimplantation, the reparative tissues were evaluated macroscopically, histologically, and biochemically. In Group T at as early as 4 weeks, histological observation, especially via safranin-O staining, suggested that the reparative tissues resembled hyaline cartilage. And we observed no fibrous tissues between reparative tissue and adjacent normal tissues. In the deeper portion of the bony compartment, the osseous tissues were well remodeled. At 4 and 8 weeks postimplantation, the mean histological score of Group T was significantly better than that of Group C (p < 0.05). The glycosaminoglycans (GAG)/DNA ratio in both groups increased gradually from 4 to 8 weeks and then decreased from 8 to 12 weeks. We herein report the first successful regeneration of cartilage in osteochondral defects in vivo using allogeneic cartilaginous aggregates derived from bone marrow-derived cells by 3D culture using the RWV bioreactor.

This is the first successful report of the rapid regeneration of three-dimensional large and homogeneous cartilaginous tissue from rabbit bone marrow cells without a scaffold using a rotating wall vessel (RWV) bioreactor, which simulates a microgravity environment for cells. Bone marrow cells cultured for 3 weeks in DMEM were resuspended and cultured for 4 weeks in the chondrogenic medium within the vessel. Large cylindrical cartilaginous tissue with dimensions of (1.25 +/- 0.06) x (0.60 +/- 0.08) cm (height x diameter) formed. Their cartilage marker expression was confirmed by mRNA expressions of aggrecan, collagen type I and II, and glycosaminoglycan (GAG)/DNA ratio. Their cartilaginous properties were demonstrated by toluidine blue, safranin-O staining, and polarization.

Polymeric systems for antibacterial wound dressings require chemical reactions or syntheses for attaching or incorporating antibacterial moieties into polymer backbones. However, these materials often fail to satisfy the basic requirements, such as easy and inexpensive synthesis. We speculated that a positively charged organic antibacterial agent would be attracted to the polar groups of poly(vinyl alcohol) (PVA) hydrogels and would show suppressed release. PVA hydrogels containing cetylpyridinium chloride (CPC) were prepared by γ irradiation. CPC was barely released from the hydrogels, probably because of electrostatic interactions, and was stable upon γ irradiation. The suppressed release of CPC conferred antibacterial activity against Escherichia coli to the surface of the hydrogels, whereas no inhibition zone was observed around the hydrogels. The CPC-containing PVA hydrogels were easy to prepare and contained known and safe materials. The simplicity and safety of this procedure for achieving the suppressed release of antibacterial agents were advantages of these CPC-containing PVA hydrogels. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40456.