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M Mochizuki

Publications and source records attributed to M Mochizuki.

At least 91 records · Page 5Linked to original sources
PubMed2000

Relationship between vanadate induced relaxation and vanadium content in guinea pig taenia coli.

Abstract: Vanadate has been known to induce a transient increase in high K+ induced contraction, and also gradually relax the high K+ contraction itself in guinea pig taenia coli. The relationship between the rate of relaxation and ion content of Na+, K+, and V ion at the cellular level was investigated when vanadate was applied to contracted muscle. Tissue Na+ and V ion content increased linearly, depending on the time after vanadate treatment, reaching maximum levels of approximately 50 mM x kg(-1) and 0.25 mM x kg(-1) wet weight, respectively. There was a positive correlation between the V ion and Na+ contents, while there was a negative correlation between both ions and the relaxed rate of the high K+ induced contraction. The uptake of V ion was affected by the external K+ concentration, and the maximum rate of V ion uptake decreased to 40% in the presence of 90 mM external K+. These results suggest that a small amount of V ion was enough to inhibit the Na+ pump activity and muscle contraction in the high K+ solution.

Animals↗
PubMed2000

[A case of multiple metastatic brain tumors with repeated intracerebral hemorrhages].

We report a case of multiple metastatic brain tumors with repeated intracerebral hemorrhages. A 73-year-old man suffered from a cerebellar hemorrhage. Subsequent hemorrhages repeatedly occurred in the right temporal lobe, the 4th ventricle, the midbrain, and the septum pellucidum. Three months after admission, CT revealed enhanced masses with surrounding edema in the cerebellar vermis and midbrain, suggesting brain tumors. We eventually diagnosed these masses in an autopsy as metastatic brain tumors of lung adenocarcinoma. Intravascular embolization with tumor cells was a probable cause of the multiple repeated intracerebral hemorrhages.

Adenocarcinoma↗
PubMed2000

Behçet's disease in Japan and in Great Britain: a comparative study.

Behçet's disease (BD) is an important cause of visual morbidity throughout the world, but shows striking differences in racial predilection. Despite important advances in the therapeutic management of acute intraocular inflammation, the long-term impact of these new strategies on visual outcome of BD and their efficacy in different ethnic groups is unknown. A comparative study of patient characteristics, clinical ocular features and inflammatory score, and current therapy was undertaken on all patients fulfilling the International Study Group criteria for Behçet's disease and the Behçet's Disease Research Committee of Japan, who attended the Uveitis Clinics of Moorfields Eye Hospital (n=19) and Kurume University School of Medicine (KUS) (n=35) during a continuous consecutive four-week period. Japanese patients were significantly older (43.2+/-11.8 years) than the patients seen in London (35.4+/-8. 9 years). There was a predominance of male patients in both groups. All patients seen in KUS were Japanese, while the patients in London included 12 Caucasians, five Middle Eastern, one African, and one Asian. No significant differences were seen between the two populations in the duration of systemic disease or systems affected by the disease, such as mouth ulcers, genital ulcers, skin lesions including erythema nodosum, or arthritis. The duration of ocular disease was similar in both centres: around seven years. There was, however, a significant difference in the number of eyes with active anterior uveitis (59.7% KUS vs 18.4% London (chi-square: 5.4; p=0.006)) and/or posterior uveitis (31.3% KUS vs 18.4% London (chi-square: 5.42; p<0.02)). No significant differences were found in the number of eyes with optic disc swelling or optic atrophy and in each centre the number of eyes with vision greater than 6/9 or worse than 6/60 were the same. The treatment schedules were very different between the two centres. More patients were treated with topical steroids in Japan (68.7% KUS vs 10.5% London (chi-square: 30.5; p=0.001), but a similar number used concomitant intraocular pressure-lowering agents. More patients received systemic steroids in London (84.2% London vs 17% KUS (chi-square: 20.25; p<0.001)). Three patients received systemic steroids alone, five had prednisolone and cyclosporin, four had prednisolone and azathioprine, and four had triple therapy with prednisolone, cyclosporin, and azathioprine. Only one patient used colchicine. Cyclosporin use was similar in London and KUS (47.4% and 42.8%, respectively). In Japan, three patients used prednisolone alone and three tacrolimus (FK506). In addition, two patients, who were on steroids alone, took colchicine as well. More patients in Japan had undergone surgery for cataract and glaucoma (chi-square: 4.0; p=0.045). In KUS, seven of 67 eyes had cataract surgery. A further three eyes had visually significant cataract and two eyes had undergone glaucoma surgery. In contrast, no patients in London had undergone any surgery up to and including this period.

Administration, Topical↗
PubMed1999

Quantitative reevaluation of the redox active sites of crystalline bovine heart cytochrome c oxidase.

Approximately 30% of the iron contained in a bovine heart cytochrome c oxidase preparation was removed by crystallization, giving a molecular extinction coefficient 1.25-1.4 times higher than those reported thus far. Six electron equivalents provided by dithionite were required for complete reduction of the crystalline cytochrome c oxidase preparation. The fully reduced enzyme was oxidized with 4 oxidation equivalents provided by molecular oxygen, giving an absorption spectrum slightly, but significantly, different from that of the original fully oxidized form. Four electron equivalents were required for complete reduction of the O(2)-oxidized enzyme. The O(2)-oxidized form, when exposed to excess amounts of O(2), was converted to the original oxidized form which required 6 electrons for complete reduction. A slow reduction of the O(2)-oxidized form without any external reductant added indicates the existence of internal electron donors for heme irons in the enzyme. These results suggest that the 2 extra oxidation equivalents in the original oxidized form, compared with the O(2)-oxidized form, are due to a bound peroxide produced by O(2) and electrons from the internal donors, consistently with a peroxide at the O(2) reduction site in the crystal structure of the enzyme (Yoshikawa, S., Shinzawa-Itoh, K. , Nakashima, R., Yaono, R., Yamashita, E., Inoue, N., Yao, M., Fei, M. J., Peters Libeu, C., Mizushima, T., Yamaguchi, H., Tomizaki, T., and Tsukihara, T. (1998) Science 280, 1723-1729).

Animals↗
PubMed1999

Carcinogenic effects of N-ethyl-N-hydroxyethylnitrosamine and its metabolites in rats and mice.

N-ethyl-N-hydroxyethylnitrosamine (EHEN), a member of the nitrosamine class of carcinogens induces renal cancer. However, since very little is known about the metabolic products of EHEN and their effects, these were investigated in rats and mice. EHEN, N-ethyl-N-formylmethylnitrosamine (EFMN) and N-ethyl-N-carboxymethyl-nitrosamine (ECMN) were administered in the drinking water for 2 weeks and the animals were then maintained until sacrifice at week 32. The urine of the rats was collected over the 2-week exposure period and analyzed by HPLC. The results showed that EHEN but not EFMN or ECMN induces tumors in the kidneys of rats. In mice the lungs were targeted not only by the parent compound but also by both metabolites. The findings suggest that the kidney is the most susceptible organ to EHEN effects in the rat while the lung is the most susceptible organ in mice. These results are consistent with inter-species variation in the metabolism of xenobiotics.

Animals↗
PubMed1999

Inhibition of E. coli growth by fullerene derivatives and inhibition mechanism.

Cationic ammonium fullerene derivatives (C60-bis(N, N-dimethylpyrrolidinium iodide) and C60-bis(N-methylpiperazinium iodide)) suppressed E. coli growth, whereas an anionic derivative (C60-dimalonic acid) did not. Both cationic derivatives inhibited E. coli dioxygen consumption. Inhibition of energy metabolism is concluded to be a mechanism of the growth inhibition effect of fullerene derivatives.

Anti-Bacterial Agents↗
PubMed1999

Effect of decompression enlargement laminoplasty for posterior shifting of the spinal cord.

STUDY DESIGN: A study to measure the shifts of the spinal cords and the effects of decompression laminoplasty in 65 patients with cervical lesions who underwent computed tomographic myelography before and after laminoplasty. OBJECTIVES: To investigate limitations of the spinal cord posterior shift after laminoplasty and to clarify the optimal decompression areas to obtain effective posterior shifting. SUMMARY OF BACKGROUND: Although several types of laminoplasty have been performed, all procedures share the common purpose of posterior decompression. No previous studies have examined the limitations of posterior decompression or the optimal decompression range. METHODS: The distance from the posterior edge of each vertebral body or disc level to the posterior edge of the spinal cord was measured by computed tomographic myelography. After the posterior shift was determined by calculating the difference between pre- and postsurgical distances, the relations between posterior shift and neck alignment, clinical results, and the areas of decompression were analyzed. RESULTS: The spinal cord shift ranged from a maximum of 6.6 mm to a minimum of 0 mm. Clinically, spinal cord shifts greater than 3 mm were associated with good clinical outcomes. Upward or downward advanced laminoplasty was related to larger spinal cord shifts at the upper or lower cervical spine. CONCLUSIONS: A mean spinal cord shift of > 3 mm was associated with good clinical outcomes after laminoplasty. In cases with compressive lesions at the upper or lower cervical spine, extension of decompression one level above or one level below likely results in a greater posterior spinal cord shift at these lesions.

Cervical Vertebrae↗
PubMed1999

Human T-cell lymphotropic virus type 1 infection and ocular manifestations in São Paulo, Brazil.

OBJECTIVES: Although human T-cell lymphotropic virus type 1 (HTLV-1)-associated uveitis has been well recognized in Japan, related studies in Brazil are scarce. We performed a serologic survey for HTLV-1 infection among patients with uveitis and investigated the ocular findings in HTLV-1-asymptomatic carriers. METHODS: One hundred ninety serum samples from patients with uveitis of determined (n = 137) and undetermined origins (n = 53) being examined at the Uveitis Service, University of São Paulo, São Paulo, Brazil, underwent testing using HTLV enzyme-linked immunosorbent assay and discriminatory Western blots. One hundred five asymptomatic blood donors and/or their relatives who were seropositive for HTLV-1 (carrier group) and 105 age- and sex-paired blood donors who were seronegative for HTLV-1 (control group) underwent ocular evaluation. For the statistical analysis, chi2 test was used. RESULTS: Only 1 patient with uveitis was seropositive for HTLV- 1, and she belonged to the group with uveitis of undetermined origin. Results of tear films were evaluated in 52 carriers. The prevalence of a decreased tear break-up time was significantly higher in the carrier compared with the control group (P = .02). Two carriers had keratoconjunctivitis sicca. Three of the 105 carriers exhibited mild uveitis (cells in the vitreous, retinal and choroidal infiltrates, retinal vasculitis, and bilateral pars planitis). Retinal pigmentary changes were found in both groups (no statistical difference). CONCLUSIONS: Early tear abnormalities may be present in asymptomatic carriers, and mild uveitis may be found among them. The relatively low seroprevalence of HTLV-1 in the Brazilian population made it difficult to establish the real importance of HTLV-1-associated uveitis among our patients with uveitis.

Adolescent↗
PubMed1999

Effects of monoclonal antibodies directed at cell surface molecules on murine experimental autoimmune uveoretinitis.

BACKGROUND: To elucidate the immunopathogenic mechanism of endogenous uveitis, the effects of monoclonal antibodies to molecules involved in the immune response were studied in murine experimental autoimmune uveoretinitis (EAU). METHODS: Monoclonal antibodies to CD4, CD8, Ia(k), Ia(d), lymphocyte function-associated antigen-1 (LFA-1), and intercellular adhesion molecule-1 (ICAM-1) were used in this study. The monoclonal antibodies were added in the culture of lymph node cells from B10.BR mice(H-2(K)) immunized with interphotoreceptor retinoid-binding protein (IRBP) and the inhibition of proliferative response was measured. In vivo, IRBP-immunized mice were treated with a high dose of the antibody, and the EAU induction was examined both clinically and pathologically. RESULTS: Proliferative response of IRBP-sensitized lymph node cells was inhibited strongly by anti-CD4 or anti-LFA-1 monoclonal antibody and moderately by anti-Ia(k) or anti-ICAM-1 monoclonal antibody. In contrast, no inhibitory effect of anti-CD8 or anti-Ia(d) monoclonal antibody was observed. In vivo treatment with anti-CD4 monoclonal antibody inhibited development of EAU in a dose-dependent manner, while in vivo treatment with other monoclonal antibodies did not cause significant suppression of EAU. CONCLUSIONS: CD4, Ia, LFA-1, and ICAM-1 molecules play important roles in the antigen-specific immune response of lymphocytes. However, in in vivo treatment with monoclonal antibodies to these molecules, only anti-CD4 monoclonal antibody had a strong inhibitory effect on the development of EAU.

Animals↗
PubMed1999

Vanadium contamination and the relation between vanadium and other elements in wild birds.

There is little information on vanadium (V) contamination in wildlife. In the present study, the mean V contents in liver and kidney from 41 wild Japanese water birds were less than 3.69 and 8.11 microg/g dry wt, respectively. The V contents in the liver and kidney of the spotbill duck were more than two times higher than those of other species in Japan. Spotbill ducks obtained in a residential district had a strong correlation between the V contents in the kidneys and those in the livers (R=0.924), and also between V and Ti, Cd, and Li contents in the liver (R>0.8). These results suggest that V accumulation in wild birds reflects the degree of environmental contamination.

Journal Article↗
PubMed1999

Cooling effect on excimer laser photorefractive keratectomy.

PURPOSE: To evaluate the effect of cooling on pain, corneal haze, and refractive outcome after excimer laser photorefractive keratectomy (PRK). SETTING: Tokyo Medical and Dental University Hospital, Tokyo, Japan. METHODS: The corneal surface was cooled before, during, and after laser ablation using a method called cooling PRK. Thirty-eighty highly myopic eyes of 38 patients whose spherical errors ranged from -8.00 to -18.75 diopters (D) were randomized into 2 groups: 16 eyes with conventional PRK and 22 eyes with cooling PRK. Postoperative pain was measured using the Visual Analogue Scale (VAS). Refraction, visual acuity, and complications were followed for up to 2 years. All data were analyzed and compared between groups to evaluate the cooling effect on PRK. RESULTS: One day postoperatively, patients in the cooling PRK group had significantly less pain (P < .01). At 3 months, the haze score in the cooling PRK group was significantly less than in the conventional PRK group (P < .01). The residual refractive error was not significantly different between the 2 groups until 2 years, when it was greater in the conventional PRK (mean -5.09 D +/- 2.11 [SD]) than the cooling PRK group (-4.64 +/- 2.27 D). Ten eyes (62.5%) in the conventional PRK group and 15 eyes (68.2%) in the cooling PRK group were within +/- 1.00 D of the intended refraction. There were no serious complications in the cooling PRK group. Two eyes in the conventional PRK group had severe corneal haze and lost 2 Snellen lines of best corrected visual acuity. CONCLUSION: Corneal cooling on PRK effectively reduced postoperative pain, corneal haze, and myopic regression.

Adult↗
PubMed1999

Isolation and characterization of a new human breast cancer cell line, KPL-4, expressing the Erb B family receptors and interleukin-6.

A new human breast cancer cell line, KPL-4, was recently isolated from the malignant pleural effusion of a breast cancer patient with an inflammatory skin metastasis. This cell line can be cultured under serum-free conditions and is tumorigenic in female athymic nude mice. Flow cytometric analysis revealed the expression of Erb B-1, -2 and -3. Dot blot hybridization showed a 15-fold amplification of the erb B-2. Reverse transcription-polymerase chain reaction analysis showed a detectable level of mRNA expression of all the Erb B family receptors. In addition, all the receptors were autophosphorylated under a serum-supplemented condition. Unexpectedly, transplanted KPL-4 tumours induced cachexia of recipient mice. A high concentration of interleukin-6 (IL-6) was detected in both the culture medium and the serum of mice. The weight of tumours significantly correlated with the serum IL-6 level. The antiproliferative effect of a humanized anti-Erb B-2 monoclonal antibody, rhuMAbHER2, was investigated. This antibody significantly inhibited the growth of KPL-4 cells in vitro but modestly in vivo. Loss of mouse body weight was partly reversed by rhuMAbHER2. These findings suggest that KPL-4 cells may be useful in the development of new strategies against breast cancer overexpressing the Erb B family receptors and against IL-6-induced cachexia.

Animals↗
PubMed1999

Comparison of sedative effects of medetomidine-midazolam, acepromazine-butorphanol and midazolam-butorphanol in dogs.

Sedative effects of medetomidine at 20 micrograms/kg and midazolam at 0.3 mg/kg (MM), acepromazine at 0.05 mg/kg and butorphanol at 0.2 mg/kg (AB), and midazolam at 0.1 mg/kg and butorphanol at 0.2 mg/kg (MB) were compared in dogs. All dogs given MM were laterally recumbent within 11 min of the administration of the drugs, and this combination also induced deep sedation accompanied by analgesia and muscle relaxation, and strongly depressed arousal reactions to external stimuli. However, undesirable effects such as bradycardia and decreased respiration were also observed in dogs given MM. Six of seven dogs given AB were laterally recumbent within 16 min of the administration of the drugs, and this combination induced relatively deep sedation but only a mild depression of arousal reactions to external stimuli. MB induced mild or moderate sedation with relatively large differences in effects among individuals. The recovery from sedation in each group was smooth and total recovery times were not significantly different.

Acepromazine↗
PubMed1999

Comparison of cardiopulmonary effects of medetomidine-midazolam, acepromazine-butorphanol and midazolam-butorphanol in dogs.

Cardiopulmonary effects of intramuscular administration of medetomidine-midazolam at 20 micrograms/kg and 0.3 mg/kg, respectively (MM), acepromazine-butorphanol at 0.05 and 0.2 mg/kg, respectively (AB), and midazolam-butorphanol at 0.1 and 0.2 mg/kg, respectively (MB), were compared in dogs. MM produced relatively large cardiovascular changes such as bradycardia, hypertension, a decrease in cardiac output and vasoconstriction. AB produced moderate cardiovascular changes. Hypotension was observed within 5 min after administration and the mean arterial blood pressure decreased by 30% at 20 min after administration. MB produced decreases in arterial blood pressure and cardiac output, but these changes were small and, of the combinations evaluated in this study, MB had the mildest cardiovascular effects.

Acepromazine↗