Biomedical subjects

H Umeda

Publications and source records attributed to H Umeda.

11 recordsLinked to original sources

PubMed1992

An experimental study of the osteogenicity of free periosteal allografts with cyclosporine A administration.

Free tibial periosteum was grafted onto the dorsum (m. cutaneous trunci) of Sprague-Dawley rats to examine its osteogenic potential. The animals were divided into 3 groups based on type of: A. autogenous periosteum, B. allogeneic periosteum and C. allogeneic periosteum, and treated with cyclosporine A immunosuppression. The osteogenic response was evaluated radiologically and histologically. This study indicates that in this model periosteal allografts with immunosuppression of the recipient result in osteogenesis. Clinical application of the technique will only be possible if immunosuppressive methods with minimal morbidity are developed so that they can be used for prolonged periods.

Animals↗

PubMed1992

[Prophylactic effect of ulinastatin on cisplatin-induced renal disorders in lung cancer patients].

In order to determine whether ulinastatin (US) can prevent renal dysfunction due to cisplatin (CDDP) or not, we comparatively studied serum BUN, serum creatinine (Cr), creatinine clearance (Ccr), urine gamma-glutamyl transpeptidase (gamma-GTP) excretion, urine N-acetyl-beta-D-glucosaminidase (NAG) excretion, fractional excretion of Na (FENa) and urine beta 2-microglobulin excretion between one group of 10 patients receiving single treatment with CDDP and another group of 10 patients receiving combination treatment with CDDP+US, in 20 subjects with primary lung cancer. In the US combination treatment group, urine gamma-GTP excretion, urine NAG excretion, and FENa elevation were significantly inhibited. Urine beta 2-microglobulin excretion was inhibited. In summary, US was considered to have a preventive effect against renal toxicity due to CDDP.

Aged↗

PubMed1989

Mechanical properties of hydroxyapatite-reinforced gelatin as a model system of bone.

The elastic Young's modulus of hydroxyapatite-reinforced gelatin as a mechanical model system of bone was measured as a function of the volume fraction of hydroxyapatite, phi h. Initially, the Young's modulus gradually increased with an increase in phi h and then increased rapidly in the vicinity of phi h approximately 0.2. The phi h dependence of the Young's modulus was analysed by means of the theory of composite materials. It was found that with the increase in phi h the initial uniform stress deformation mode of the sample changed to the uniform strain deformation mode. The non-linear character in phi h dependence of the Young's modulus of this system was considered to reproduce well the novel behaviour of the mechanical properties of bone as a function of the mineral fraction. The situation was considered to be similar to a percolation problem. A preliminary analysis revealed that the critical exponent about the viscosity of the system accorded with the theoretically expected value. The result may present the evidence that the discontinuous point in mechanical properties of bone would be originated from an interaction such as a percolation of mineral particles on a matrix protein.

Biomechanical Phenomena↗

PubMed1979