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K Morisawa

Publications and source records attributed to K Morisawa.

16 recordsLinked to original sources
PubMed1995

Effect of poly(ADP-ribose) synthetase on the expression of major histocompatibility complex (MHC) class II genes.

We have studied the effect of poly(ADP-ribose) synthetase on the interferon-gamma (IFN-gamma)-inducible expression of major histocompatibility complex (MHC) class II molecules. We constructed an expression plasmid capable of expressing either a sense RNA (MT-ARS) or an antisense RNA (pAS-FL or pAS-5') for poly(ADP-ribose) synthetase. We transfected the plasmid into mouse or human macrophage tumor cells and examined the effect on the expression of MHC class II molecules. The IFN-gamma-inducible expression of MHC class II gene was considerably reduced in transformant clones (A-2, B-2), in which the synthetase was highly expressed, whereas the depletion of the synthetase due to the expression of antisense RNA for the synthetase amplified the expression of MHC class II molecules. The results indicate that the level of the synthetase critically regulates the IFN-gamma-inducible MHC class II molecules. Next, we analyzed DNase I hypersensitive sites (DHS) of mouse MHC class II, I-A beta gene and found two sites, one in the promoter region and the other one in the first intron. The DHS in first intron was less sensitive towards DNase I attack in transformant clones (A-2, B-2) in which the synthetase was synthesized in a large quantity. Thus we constructed two beta-galactosidase reporter genes, one (A beta 2.0kb-lac z) containing the promoter region to a part of the second exon of the class II gene, and the other (A beta pro-lac z) containing the promoter region of the class II gene alone. The expression of the reporter gene was analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) and found that the expression of A beta 2.0kb-lac z was suppressed in the transformant clones (A-2, B-2) relevant to control cells but the expression of A beta pro-lac z was the same level among those cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Factors contributing to cerebral hypomyelination in the growth hormone-deficient little mouse.

We attempted to delineate the events leading to hypomyelination in the brain of the little mouse, a promising murine model of isolated growth hormone deficiency. At 20 days of age, the mutant mouse brain weighed less than its normal counterpart, and this difference in brain weight persisted. Increase in CNPase activity was found to be suppressed in the cerebrum throughout the developmental stage, but not in the other parts of the brain. Differences in cerebral DNA content between the little and normal mice first became apparent on the 10th day of age. Thereafter, the rate of increase in the little brain consistently lagged behind the normal. [3H]Thymidine incorporation into the DNA fraction in vivo on the 7th day of age, when glial cell proliferation in the normal cerebrum is most active, was approximately half that of the controls in all parts of the little brain. These findings indicate that the hypomyelination of the mutant cerebrum might result from reduced oligodendroglial proliferation due to growth hormone deficiency.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗
PubMed1988

Decrease in the level of poly(ADP-ribose) synthetase during nerve growth factor-promoted neurite outgrowth in rat pheochromocytoma PC12 cells.

We have studied the changes in the levels of the enzyme molecule and mRNA for poly(ADP-ribose) synthetase during nerve growth factor-promoted neurite outgrowth in rat pheochromocytoma PC12 cells. When the PC12 cells were cultured in the presence of nerve growth factor, the content of enzyme molecules decreased along with neurite outgrowth to 50% of the original amounts in 2 days and the content of mRNA for the enzyme also decreased to approximately 50% in 2 days. These results suggest that the decrease of the enzyme molecule may be due to depression of expression of the gene for synthetase during the process. Taken together with previous observations, the decrease of the synthetase seems to be required for some cellular differentiation.

Adrenal Gland Neoplasms↗
PubMed1988

Persistent hemarthrosis of the shoulder joint with a rotator-cuff tear in the elderly.

Three elderly patients developed persistent hemarthrosis of the shoulder joint without having suffered injury. Complete tears of the rotator cuff, attrition of the undersurface of the acromion, and instability were noted in the affected shoulders. Synovial fluids examined from two patients contained many alizarin red S-positive microspheroids. The synovium obtained at surgery from two patients showed hypervascularity, vasodilatation, and severe degenerative changes of collagenous tissues. The tendon of the m. supraspinatus showed infiltrations of multinucleated giant cells around calcified deposits consisting of hydroxyapatite crystals. Anatomical and mechanical derangements, and possible biological reactions following phagocytosis of hydroxyapatite crystals, may have contributed to the persistent hemorrhage in the shoulder joints.

Acromion↗
PubMed1988

[A study of an immunosuppressive acidic protein (IAP) in patients with a bone tumor].

We evaluated an immunosuppressive acidic protein (IAP) as a tumor marker in cases of a tumor of the bone (benign, 21; primary malignant, 26; metastatic carcinoma, 12). The IAP positive rate of a primary malignant tumor of the bone was 60%, and the mean was 591 + 59.4 micrograms/ml. This rate of a benign tumor of the bone was 10%, and the mean was 382 +/- 31.3 micrograms/ml. IAP may represent a tumor marker in malignant tumors of the bone.

Biomarkers, Tumor↗
PubMed1987

Management of thoracic outlet syndrome.

The experience with transaxillary first-rib resection and scalenotomy reported herein shows these to be safe and effective treatments for patients with thoracic outlet syndrome (TOS). The former operation usually offers the best possibility for complete resection of the first rib and all anomalous congenital bands, and is curative in most cases, regardless of the mechanism of the compression. Scalenotomy, or Powers' operation, is also helpful, in particular for cases of TOS with a vertebral arterial insufficiency. Accurate diagnosis of TOS and selection for surgery after a detailed history and proper physical examination will result in gratifying relief of symptoms in almost all patients with TOS.

Adult↗
PubMed1985

Enhancement of methyl mercury-induced lipid peroxidation by the addition of ascorbic acid.

Effects of mercuric chloride (HgCl2) and methylmercuric chloride (MMC) in the presence of ascorbic acid on lipid peroxidation in rabbit renal cortical mitochondria were studied. The addition of ascorbic acid showed no effect on HgCl2-induced lipid peroxidation, but ascorbic acid plus MMC were able to stimulate the lipid peroxidation markedly. This result suggests that in the presence of ascorbic acid MMC has a powerful stimulatory effect on the lipid peroxidation in mitochondria.

Animals↗
PubMed1983

A study of the acid phosphatase in the cells of bone and soft parts tumors, and of other tumorous conditions.

The acid phosphatase in the cells of bone and soft parts tumors, and of other tumorous conditions in our Department of Orthopedic Surgery in Kumamoto University Medical School from mid-1979 through mid-1983 were analysed by light microscopic and electron microscopic histochemical studies and their inhibition studies. The histochemical and their inhibiting studies of acid phosphatase by azo dye method in the cells of bone and soft parts tumors and of other tumorous conditions were undertaken in order to characterize them with a view to providing helpful diagnostic features. The acid phosphatase in some giant cells and tumor cells of several kinds of tumors, whose reaction against inhibitors was different from that of lysosomal acid phosphatase, was observed. In the giant cells of giant cell tumor of bone, acid-para-nitrophenyl phosphatase was demonstrated by the method of Miyayama , et al. using sodium-para-nitrophenyl phosphate as a substrate. In addition, the fine structural localization of acid phosphatase in giant cell tumor of bone was studied by Gomori's method and by the method of Miyayama , et al. By Gomori's method, acid phosphatase activity was demonstrated in lysosome, secondary lysosome-like organelles and the digestive vacuoles in the giant cells. In the stromal cells, that activity was demonstrated in lysosomes. By the method of Miyayama , et al., acid para-nitrophenyl phosphatase was demonstrated in the Golgi complex and the cisternae of the rough endoplasmic reticulum in the giant cell. Therefore, in the giant cells and the tumor cells of some kinds of tumors, non-lysosomal acid phosphatase besides lysosomal acid phosphatase was recognized. The demonstration of non-lysosomal acid phosphatase was a useful tool for the differential diagnosis of tumors and tumorous conditions in bone and soft parts.

Acid Phosphatase↗
PubMed1980

Comparative studies on absorption patterns of the drug after intrarectal administration of 5-FU emulsion and 5-FU solution.

Intrarectal administration of 5-fluorouracil (5-FU) emulsion was compared experimentally with that of 5-FU solution as to the degree of absorption and tissue distribution. For the 5-FU levels in the rectal wall, the levels in the emulsion group remained at high levels during the 6 hour period after administration while the levels in the solution group decreased rapidly. For the 5-FU levels in the lymph nodes, those in the emulsion group were significantly higher (more than four times) and remained at relatively high levels for a longer period than those in the solution group. In the thoracic lymph, 5-FU levels in the emulsion group remained more than two times higher throughout the experimental period. The results suggest tha preoperative intrarectal administration of 5-FU emulsion may be effective as an adjunct to surgery for rectal cancer with lymph node metastasis, because of the long duration of high concentration resulting in the rectal lymphatics and rectal wall.

Animals↗
PubMed1980

Clinical studies of intrarectal administration of 5-FU emulsion as an adjunct to surgical treatment of rectal cancer.

Preoperative intrarectal administration of 5-FU emulsion was attempted as an adjuvant chemotherapy to surgery for rectal cancer. The drug concentrations of resected specimens were determined and histological examinations of them were carried out in order to evaluate the effect of anticancer drugs on the metastatic lymph nodes as well as on the primary tumors. 5-FU levels both in the regional lymph nodes and primary tumors of 18 patients with rectal cancer, who were given with the 5-FU emulsion (emulsion group) or 5-FU suppository (suppository group) intrarectally two hours before surgery, was found to be much higher in emulsion group than in suppository group. 46 patients with rectal cancer were treated preoperatively with intrarectal administration of 5-FU emulsion (25 cases) or 5-FU suppositories (21 cases) for a period of 10 days before surgery, and the histological effect of this regimen on the metastatic lesion in the lymph nodes, as well as in the primary tumor was examined. No detectable difference was found in the primary lesions between the emulsion group and the suppository group. In the metastatic lesions, however, the rate of effectiveness was higher in the emulsion group than in the suppository (68 percent versus 33 percent).

Emulsions↗
PubMed1978

Histological evaluation of the effect of 5-FU emulsion on lymph node metastasis of stomach cancer.

In order to evaluate the effect of anticancer drugs on the metastatic lesions of the regional lymph nodes from stomach cancers removed after oral administration of 5-FU emulsion, histological examinations of the specimens obtained from 107 surgical cases were carried out. In additional 13 cases with gastric cancer, the active 5-FU concentrations in the regional lymph nodes were determined. The effect of 5-FU emulsion in metastatic lesions as determined was histologically classified into Grades 0 to III according to the severity and extent of damaged cells and cell nests Grades II and III were judged to demonstrate the beneficial effect of the 5-FU emulsion. Such changes were identified in 62.0 per cent of the 242 metastatic lymph nodes, and the effectiveness increased as the total dose of the 5-FU emulsion administered increased (50.9 per cent for 5,000 mg or less, 70.9 per cent for 5,000 to 6,000 mg, and 72.7 per cent for 6,000 mg or more). The rate of effectiveness also varied with the histological type of the primary carcinoma, i.e. the differentiated type being more sensitive. The mean active 5-FU level in the regional lymph nodes was higher after the administration of 5-FU emulsion than of 5-FU solution supporting the earlier animal experiments.

Adenocarcinoma↗
PubMedDate not supplied

Brachial plexus stretching injuries: microcirculation of the brachial plexus.

This study was undertaken to investigate the pathogenesis of brachial plexus stretching injuries at an intensity level not severe enough to cause avulsion injury. While we performed traction on 64 forelegs of 32 rats, we evaluated changes in the blood flow in the extrinsic and intrinsic microvascular systems of the brachial plexus. While we laterally stretched the brachial plexus during 80 degree shoulder abduction, we measured the blood flow at the bifurcation of the brachial plexus and at the median nerve with the hydrogen washout technique. During weak traction the blood flow decreased markedly in the extrinsic system, causing an imbalance in the two systems. In the median nerve, however, no such imbalance occurred. On histologic examination the axon and myelin in the brachial plexus and the median nerve showed no morphologic change. However, in parts of the brachial plexus we noted hypertrophic connective tissue or granulomatous inflammation in tissue surrounding the extrinsic system. The extrinsic system's apparent susceptibility to injury by acute traction may be a factor in the pathogenesis of the brachial plexus stretching injuries.

Animals↗