Biomedical subjects

H A Reddi

Publications and source records attributed to H A Reddi.

3 recordsLinked to original sources

PubMed1987

Tumor cells stimulate in vivo periosteal bone formation.

It was demonstrated that in mice a variety of tumor cells of both viral (XC, MSVC) and non-viral origin (rat ameloblasts, Ehrlich ascites carcinoma, KB, WAMIB, WISH cell lines) produce, on transplantation in the adjacent bones, periosteal osteogenesis, and in addition can stimulate osteoclastic and tumor-mediated bone resorption. The production by the tumor cells of an osteoblast-activating factor, besides the osteoclast-activating factor described earlier by others, is postulated.

Animals↗

PubMed1987

New bone formation and bone marrow differentiation induced in rats by extracellular bone matrix implantation: effect of local preirradiation on the process.

Subcutaneous implantation of demineralized diaphyseal rat bone matrix in ACI rats initiates a developmental cascade that results in the formation of new endochondral bone and an associated hematopoietic bone marrow differentiation. Irradiation (1500 rad, 60Co) of the implantation site 24 h prior to implantation suppresses the formation of endochondral bone and bone marrow. All phases of the developmental cascade, including chemotaxis, proliferation, and differentiation, are arrested by the irradiation. Simultaneous implantation with the extracellular matrix of bone marrow, bone, pieces of a four-day-old implant or of thoracic muscle--but not of brain, liver, or spleen tissue--results in the development of endochondral bone and bone marrow at the irradiated site. Concurrent implantation with the extracellular matrix of in vitro growing fibroblasts of marrow or ossicle origin does not restore the developmental cascade.

Alkaline Phosphatase↗

PubMed1986

Heterotopically induced bone does not develop functional periosteal membrane.

Heterotopic bone induced in mice by implantation of demineralized rat bone matrix does not respond to Moloney sarcoma. The biochemical and morphological parameters of osteogenesis (alkaline and acid phosphatase activity, 45Ca-uptake and total calcium content) are similar in the sites of Moloney sarcoma as in the contralateral, unexposed to the sarcoma, side. In contrast, periosteum of implants of syngeneic costal bone in response to Moloney sarcoma proliferates and produces new bone in the same manner, as orthotopic bones at the sites of Moloney sarcoma do. It is concluded that ectopically induced bones do not develop a true periosteum.

Animals↗