Biomedical subjects
M Ishizawa
Publications and source records attributed to M Ishizawa.
Immunohistochemical analysis of spinal intradural xanthomatosis developed in a patient with phytosterolemia.
Multiple intradural xanthomatous tumors developed in 48-year-old female with familial phytosterolemia. These tumors were restricted to the spinal denticulate ligaments. Histological and immunohistochemical findings were fundamentally similar to those of tendinous xanthomas. The major cellular component of these tumors were identified as of mono-histiocytic origin because they possessed myeloid histiocytic antigen (Mac 387), CD11c and lysozyme but not CD15. Sitosterols, campesterols and cholestanols were recovered from the extract of the tumors and the lesions were confirmed to be phytosterolemic xanthomas. Schwann cells stained with anti-S100 protein were confined to the perivascular small nerve bundles and did not show xanthomatous change. Although immunohistochemical preparation of epithelial membrane antigen and desmoplakin I+II revealed the presence of non-neoplastic meningothelial cells in the superficial portion of the tumors, they were too few to play a significant role in the development of these xanthomas.
Structural similarity of the HLA-DQ region in DQ3 and DQ4 haplotypes and structural diversity of the HLA-DQ region in HLA-DR7 haplotypes.
Genomic DNA obtained from a B lymphoblastoid cell line was digested with appropriate restriction endonuclease and hybridized with several probes specific for genes encoding HLA-DQ. Southern hybridization with a DQA1 3'untranslated (UT) region probe showed DQ2-type hybridization pattern in DR7DQ3 haplotype. On the contrary, DQB1 3'UT probe showed DQ3-type pattern in the same haplotype. Gene cloning and DNA sequencing analysis revealed a repetitive sequence, (TG)19, between DQA1 and DQB1 gene in the DR7DQ3 haplotype. These results suggest that a recombination event has occurred near this potential Z-DNA structure in the haplotype, DR7DQ3. The 3'UT region probes of DQA1 and DQB1 genes failed to detect restriction fragment length polymorphism (RFLP) differences between DR4DQ3 and DR4DQ4 haplotypes in this experiment, suggesting that the gene structure between DQA1 and DQB1 is conserved in these haplotypes.
Leftward search in left unilateral spatial neglect.
The authors' previous study with an eye camera revealed that when asked to mark the centre of a line patients with left unilateral spatial neglect persist in fixating a point on its right part and place the subjective midpoint there without searching leftwards. The present study examined the patterns of leftward search of nine patients with left unilateral spatial neglect when they were required to search for the left endpoint of the line after the bisection. The patients could search leftwards beyond the subjective midpoint to place the mark at the subjective left endpoint. The initial fixation in this search always fell near the point located to the left of the subjective midpoint by the distance between the subjective midpoint and the right endpoint of the line. In patients with severe neglect the search further to the left of this point was laborious and fell short of the true left endpoint in about 80% of the trials. Our results suggest that when asked to bisect a line patients with left unilateral spatial neglect subjectively see the line as it extends equally to either side of the point where they are going to mark the subjective midpoint.
Resolution of possible paradoxical responses of gonadotropins to thyrotropin-releasing hormone with bromocriptine therapy in a patient with follicle-stimulating hormone-secreting pituitary adenoma.
We report the effectiveness of bromocriptine therapy in resolving the abnormal responses of plasma FSH and LH to TRH in a 70-year-old male with FSH-secreting pituitary macroadenoma who had unsuccessful transsphenoidal pituitary surgery. In the pre-treatment and post-operative periods, respectively, basal plasma levels of FSH were increased to 88.7 and 65.6 mIU/ml (normal range; 8.5-32.4) but those of plasma LH were normal being 7.0 and 4.1 mIU/ml; (normal range; 4.1 to 14.0). The responses of plasma FSH and LH to LHRH were exaggerated and their paradoxical responses to TRH were highly suggested. During the bromocriptine therapy, the basal level of plasma FSH was normalized and that of plasma LH remained normal. The magnitude of FSH and LH responses to LHRH decreased and their paradoxical responses to TRH were completely resolved.
[Coagulation and fibrinolysis in pregnancy].
We studied on coagulation and fibrinolysis systems during pregnancy by measuring plasma levels of thrombin-antithrombin III complex (TAT), plasmin-alpha 2 plasmin inhibitor complex (PIC), fibrinogen/fibrin degradation products (FDP), plasminogen (PLG) and antithrombin III (AT-III). Ninety seven pregnant, 5 post-delivery and 32 nonpregnant women aged from 20 to 52 years old were included in this study. Plasma concentrations of TAT and PIC in nonpregnant women were 3.38 +/- 1.02 micrograms/l and 0.65 +/- 0.24 micrograms/ml, respectively. TAT gradually increased with the progression of pregnancy and rapidly decreased after the delivery. Whereas PIC and AT-III concentrations did not change significantly during pregnancy. Fibrinogen, PLG and FDP concentrations changed similarly as TAT. Eight pregnants whose plasma PIC concentrations elevated more than 1.0 micrograms/l were further examined. In 6 women out of them (71.5%), FDP concentrations were elevated. In this particular group of subjects, however, they delivered normally without complications such as toxemia. These observations suggest that, at least, a hypercoagulative state progresses with pregnancy, being normalized after the delivery. Although we could not find the relationship between the hypercoagulation and clinical complications such as thrombosis and toxemia of pregnancy, present findings suggest that special caution should be paid on the pregnants whose TAT and FDP levels are elevated.
Diversity in mRNA encoding soluble form MHC class I-like molecules in human tissues.
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Mechanical effects of 16-methyl analogues of PGE2 on the circular and longitudinal muscles of the guinea-pig isolated colon.
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Simple procedure of DNA isolation from human serum.
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Contractile effects of 16-methyl analogues of PGE2 on the circular and longitudinal muscles of the guinea-pig isolated colon.
The mechanical effects of 16-methyl analogues of PGE2, mainly 16,16-dimethyl PGE2, on circular and longitudinal muscles of the guinea-pig isolated proximal colon were investigated. In circular muscle strips, PGE2 100 nM produced an initial contraction followed by relaxation, while 16(R)-methyl PGE2 and 16,16-dimethyl PGE2 (1 nM - 1 microM) produced sustained contractions. In longitudinal muscle strips, PGE2 and 16-methyl analogues of PGE2 produced only contractions. The contractile responses of both muscle strips to 16,16-dimethyl PGE2 were not influenced by atropine or tetrodotoxin, indicating that these analogues act directly on the muscles, but were eliminated by the omission of extracellular Ca ions or in the presence of 1 mM lanthanum ions. However, verapamil, a Ca channel blocker, did not block the contractile response to the methyl analogues in circular muscle strips, although it completely inhibited the contractile response of longitudinal muscle strips. These results suggest that the contractile effect of 16-methyl analogues of PGE2 on the circular muscle may be due to an increased influx of Ca ions mainly via receptor-sensitive and partly voltage-sensitive Ca channels, while the contractile effect of the analogues on the longitudinal muscle may be due to an increase in influx of Ca ions via voltage-sensitive Ca channels.
Stimulation of Mn-superoxide dismutase expression by tumor necrosis factor-alpha: quantitative determination of Mn-SOD protein levels in TNF-resistant and sensitive cells by ELISA.
Marked increase in protein levels of Mn-superoxide dismutase (Mn-SOD) was found in TNF-resistant cell lines after treatment with Tumor Necrosis Factor (TNF). No such increase was observed in Cu,Zn-superoxide dismutase (Cu, Zn-SOD) protein in either TNF-resistant or sensitive cells. These results support the data that the Mn-SOD is one of the rescue proteins required for resistance to TNF cytotoxicity in these cell lines (Wong et al., Cell 58, 923-931, 1990). Mn-SOD was also responsive to TNF stimulation in KURAMOCHI, a human ovarian adenocarcinoma cell line. This may explain our previous result that Mn-SOD protein is highly expressed in epithelial ovarian cancer (Ishikawa et al. Cancer Res. 50, 2538-2542, 1990).
Effect of 2-methyl-5-hydroxytryptamine on motility of the isolated guinea-pig colon.
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[Analysis of therapeutic efficacy of combined radio-chemotherapy, pre-radio-therapy in 61 cases of non-Hodgkin's lymphoma].
Treatment results were retrospectively analyzed in 61 cases of non-Hodgkin's lymphoma (stage I: 21 cases, stage II: 40 cases) that were diagnosed between July, 1977 and Oct., 1987. The actuarial five-year survival rates for stages I and II were 84.4% and 50.7% respectively, whereas those were 47.5% and 75.3% respectively for those treated by radiotherapy (XRT) alone and combined radio-chemotherapy including all cases of stage I and II. Also the results of combined radio-chemotherapy were significantly better than those of XRT alone. Particularly, the pre-radio-chemotherapy group had a 5-year survival rate of 85.7%. In conclusion, the results of combined radio-chemotherapy, particularly pre-radio-chemotherapy, was significant between those of XRT alone.
Effects of 5-HT3 receptor antagonist on motility of the isolated guinea-pig colon.
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[Effect of vasoactive intestinal peptide on the motility of guinea-pig colon in vitro].
The effects of vasoactive intestinal peptide (VIP) on longitudinal and circular muscle strips of guinea-pig proximal and distal colons, and on propulsive activity of guinea-pig distal colon were investigated in vitro. VIP (10(-9)-10(-6) M) produced relaxations of longitudinal and circular muscle strips in proximal colon and of circular muscle strip in distal colon, but produced a contraction of longitudinal muscle strip in distal colon. VIP-induced responses of the muscle strips were not influenced by indomethacin (10(-6) M). Tetrodotoxin (10(-6) M) and atropine (10(-6) M) converted VIP-induced contraction into relaxation in longitudinal muscle strip of distal colon, although these nerve blockers did not influence VIP-induced relaxations of longitudinal and circular muscle strips in proximal colon and of circular muscle strip in distal colon. VIP (10(-6) M) inhibited spontaneous and carbachol (10(-8) M)-stimulated propulsive activities of the isolated segment in distal colon. These results suggest that VIP may directly relax colonic smooth muscle cells and may indirectly contract longitudinal muscle strip of distal colon, mainly via stimulation of cholinergic neurones in the myenteric plexus of the muscle strip. It is also suggested that VIP-induced watery diarrhea in WDHA syndrome may not due to a direct stimulation of colonic motility.
Ingestion of parsley inhibits the mutagenicity of male human urine following consumption of fried salmon.
The urinary mutagenicity of 3 nonsmoking, healthy men was investigated after strictly defined meals by means of the Ames Salmonella/microsome test. When the subjects ate 150 g of fried salmon at one meal, a potent mutagenicity of almost 5000 revertants of TA98 strain was present in all 6-h urine samples. On the other hand, less than 2500 revertants was present in the urine when the subjects simultaneously consumed 70 g of parsley and 150 g of fried salmon. Thus, the protection against mutagenicity affected by parsley warrants further attention.
Mutagenicity of human urine after the consumption of fried salted salmon.
Mutagenicity in the urine of four non-smoking individuals who had eaten salted salmon cooked at home for both lunch and supper was monitored by means of Salmonella/microsome mutagenicity tests. Extracts from fresh and salted salmon had the same level of mutagenicity after being cooked for 10 min at 200 degrees C, but no activity was detected before cooking. Salmonella strains TA98 and TA1538 were equally sensitive to the mutagens and required metabolic activation. No mutagenicity was shown with TA100 and TA1535. Urine samples were tested using a concentrate prepared by means of an XAD-2 resin column. Mutagenicity was detected mainly in urine excreted during 4-5 hr after the ingestion of cooked salmon, but only weak mutagenicity, or none at all, was detected in the urine after the ingestion of vegetables. The levels of urinary mutagenicity due to salmon consumption were not affected when cabbage was eaten simultaneously. The excretion of mutagenic substances was completed within about 20 hr, and there were almost no mutagens in the urine 24 hr after the ingestion of cooked salmon.
[Effects of GABA and homotaurine on the colonic motility of the guinea pig].
The effects of GABA (gamma-aminobutyric acid) and homotaurine (3-aminopropane sulfonic acid) on propulsive activity of the isolated segment, and on longitudinal and circular muscle strips were investigated in the guinea-pig distal colon. GABA (0.1 and 1 mM) inhibited spontaneous propulsive activity with a reduction of longitudinal tension of the segment. Homotaurine (1 mM) slightly inhibited spontaneous propulsive activity. GABA (0.01-1 mM) relaxed both longitudinal and circular muscle strips. Homotaurine (1 mM) slightly relaxed circular muscle strip. Desensitization to GABA and homotaurine was observed. The inhibitory effects of GABA on both muscle strips were abolished by tetrodotoxin or atropine, but not by bicuculline. Carbachol-induced contractions on both muscle strips were not influenced by GABA or homotaurine. These results suggest that GABA-induced inhibition of propulsive activity in the isolated colonic segment may result from activation of GABAB receptor on the cholinergic neurones in the wall, which in turn leads to reduction of release of transmitter acetylcholine.