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Biomedical subjects

K Mimatsu

Publications and source records attributed to K Mimatsu.

44 records · Page 3Linked to original sources
PubMed1990

[An evaluation of cervical spinal canal stenosis--a correlation with cerebrospinal fluid pressure using a semiconductor and its coefficients].

This study was conducted to determine whether the cerebrospinal fluid pressure (CSFP) obtained by the lumbar puncture technique is capable of evaluating the pathological state of the cervical spinal canal stenosis (CSCS). A method was developed in which the CSFP was measured with a small piezoelectric semiconductor in combination with the lumbar puncture technique. The data thus obtained were quantitatively analysed using a personal computer. Using this method, we studied patients with cervical myelopathy due to vertebral canal stenosis. The CSFP wave form obtained by compression of the cervical region was converted into a regression curve using the computer. In order to estimate the vertebral canal stenosis ratio (spinal cord/dural tube) of patients with CSCS by CSFP, multiple regression analysis was performed to obtain a multiple regression with respective parameters as expository variables. Descending curve coefficients (CND, CFD and CED) were found to be useful as parameters estimating the state of CSCS by means of CSFP analysis. On the basis of these parameters, CND, the coefficient of a descending curve obtained at the neutral cervical position, and CED, the coefficient of a descending curve obtained at the extended position, patients with CSCS were able to distinguish from normal subjects. The multiple regression equation (Y = 73.2-3890 CNA-4740 CND + 3620 CFD-10470 CEA-802 CED-0.119 NPP) was statistically significant at P = 0.01, therefore, useful in estimating the vertebral canal stenosis ratio. On the contrary, the values calculated from the multiple regression equation were not well correlated with either the JOA (Japanese Orthopedic Association) scores evaluated in accordance with the JOA Criteria or with the spinal compression ratio (anterior-to-posterior diameter/right-to-left diameter).

Aged↗
PubMed1990

Experimental chemonucleolysis with chondroitinase ABC.

Chemonucleolysis has recently become an established treatment for intervertebral disc protrusion. However, the exact mechanism of chemonucleolysis is still unknown. If mechanisms of chemonucleolysis include diminution of intradiscal pressure followed by subsequent regeneration of the nucleus pulposus, then a more selective enzyme for glycosaminoglycan, chondroitinase ABC, might be used for chemonucleolysis instead of chymopapain. Thus experimental chemonucleolysis with chondroitinase ABC compared with chymopapain was investigated. In rabbits, chondroitinase ABC is as effective for chemonucleolysis as chymopapain, but the chemonucleolysis process with chondroitinase ABC was milder than with chymopapain. At an early chemonucleolysis phase, chondroitinase ABC action was chiefly limited to digestion of the matrix, and a large number of cells in the nucleus pulposus remained. During long-term observations of chemonucleolysis with chondroitinase ABC, nuclear structure was restored to a nearly normal state. Although limited, this study indicates that chondroitinase ABC might be more suitable than chymopapain for chemonucleolysis.

Animals↗
PubMed1987

[Radiographic estimation of vertebral rotation].

Although there are various methods such as that of Nash and Moe, to measure the degree of vertebral rotation in patients with scoliosis, no decisive method has been established to date. In the present study, a formula for estimation of the pedicle rotation ratio (PRR) was obtained, based on the results of measurements of 5 dry cadaver vertebrae to establish a reasonably accurate quantitative determination of the degree of vertebral rotation on a routine antero-posterior roentgenogram of the spine. The formula could be written as: Y = AX - B(X: PRR, Y: a degree of vertebral rotation, A and B: variable according to the level of the vertebrae). The degree of vertebral rotation was obtained on antero-posterior roentgenograms of 150 vertebrae from 29 patients with idiopathic scoliosis, and was also measured on computerized tomograms of these patients for comparison. There was statistically significant relationship between the results of two methods. The present appears to be useful for clinical evaluation of scoliosis.

Adolescent↗
PubMed1982

Effects of electric current on chondrogenesis in vitro.

The effect of direct electric current (5 muamp) on mesenchymal cell differentiation into cartilage was investigated in explants of fetal rat muscle and bone matrix gelatin. In this system, chondrogenesis in vitro corresponds in developmental potential to osteogenesis in vivo. Application of electric current inhibited differentiation of muscle derived mesenchymal cells, but enhanced proliferation of differentiated chondrocytes and formation of cartilage at the cathode region, and had no effect on mature hypertrophic chondrocytes. Application of electric current may be contraindicated in fracture at the very early stage of fracture treatment and effective at the cathode region only for preexisting and proliferating cells. Electric current also may not be effective for mature cells having no potential for proliferation.

Animals↗
PubMed1979

[Quantitative measurement of the tendon reflexes. A study on Achilles tendon reflex (author's transl)].

Quantitative analyses of tendon reflexes were performed for the purpose of clinical application. Tendon tap was marked with a WNS-5D semiconductor load cell inserted in the hammer to measure tapping force. Achilles tendon reflex (ATR) was measured with a LAS-0.1 displacement transducer in kneeling position on the chair. In ATR, six factors, i.e. duration of reaction time, the height of the wave, the time from the hammer tap to the top of the wave, the maximum speed of contraction, the time from the hammer tap to the maximum speed and half relaxation time, were analyzed. Correlation between these six factors were discussed. From the analyses of these factors, half relaxation time may serve as the best indicator of clinical status among the factors obtained by analysis of ATR.

Achilles Tendon↗