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Biomedical subjects

H Nishitani

Publications and source records attributed to H Nishitani.

At least 127 records · Page 7Linked to original sources
PubMed1991

Bone mineral loss in patients on maintenance hemodialysis with hyperphosphatemia treated with 1 alpha-hydroxycholecalciferol and calcium carbonate.

We investigated the relationship between bone mineral density loss and mean serum phosphate level for one year in 58 men on maintenance hemodialysis who were treated with 1 alpha-hydroxycholecalciferol and calcium bicarbonate. Bone mineral density of the femur head and neck was measured twice, 8 months apart, by dual energy X-ray absorptiometry (Hologic QDR 1000). Patients were divided into two groups according to their mean serum phosphate level during the year of the study. Group A had almost normal serum phosphate levels (mean, less than 6.0 mg/dl) and group B had hyperphosphatemia (mean, greater than or equal to 6.0 mg/dl). In group A, the mean bone mineral density was 0.825 +/- 0.122 g/cm2 at the beginning of the study and 0.828 +/- 0.118 g/cm2 8 months later. In group B, these values were 0.787 +/- 0.167 g/cm2 at the beginning and 0.762 +/- 0.171 g/cm2 8 months later. Bone mineral density did not decrease in group A, but it decreased significantly in group B (p less than 0.01). For all patients, the percent increase in the bone mineral density was inversely correlated with the mean serum phosphate value for the year of the study (r = -0.274, p less than 0.05). These results indicate the importance of serum phosphate control in patients on maintenance hemodialysis, even when they are being treated with 1 alpha-hydroxycholecalciferol and calcium carbonate.

Adult↗
PubMed1991

Immunological detection of the dystrophin molecule with antibody directed against the synthetic peptide.

We synthesized a peptide designated R8 (amino acid residues 1157-1201) based on the primary structure presumed from the nucleotide sequence of the cDNA clone from the gene for Duchenne muscular dystrophy. Antibody to the synthetic R8 generated by immunization of rabbits was tested on human and mouse skeletal muscle by Western blotting analysis. The antibody reacted with a component of the 400K dystrophin of normal human and mouse skeletal muscles, but not with components of the muscles of Duchenne muscular dystrophy patients and mdx mice. Thus we established that this peptide sequence is in fact missing in the protein product 'dystrophin' encoded by the DMD gene. The antibody may prove useful for the diagnosis of the Duchenne types of muscular dystrophy.

Amino Acid Sequence↗
PubMed1991

[In-vivo 19F-MRS study of 5-fluorouracil (5-FU) metabolism on tumors].

5-Fluorouracil (5-FU) metabolism on tumors was studied by in-vivo 19F-MRS (magnetic resonance spectroscopy). In this study, two kinds of tumors were used, i.e., Yoshida sarcoma implanted subcutaneously to the abdomen of rats and drug-induced tumors in the rats livers. Sequential 19F spectra were obtained just after 150 mg/kg 5-FU injected intravenously. In Yoshida sarcoma, the accumulation of 5-FU was observed and disappearance of 5-FU was slower compared to the normal tissue. However, synthesis of fluoronucleotides (Fnct) could not be detected. In drug-induced liver tumors, the peak of fluoro-beta-alanine (FBAL) was observed. Disappearance of 5-FU and catabolism to FBAL in the liver tumors group were slower compared to the normal liver. Synthesis of Fnct did not increase in the liver tumor group. The results in the liver tumor group are considered to be the confined result of the hepatocytes and tumors cells. It was considered that the delayed catabolism to FBAL in the liver tumor group showed metabolic dysfunction of the liver. Also the synthesis of Fnct in tumors could not be detected by in-vivo 19F-MRS. 19F-MRS method could not detect Fnct in tumors in-vivo. However, the accumulation of 5-FU could be assessed by this method. It is expected that the evaluation of 5-FU pooling in tumors could be used for the index of chemotherapeutic effect.

Animals↗
PubMed1991

Carbonic anhydrase III in serum in muscular dystrophy and other neurological disorders: relationship with creatine kinase.

We measured with a radioimmunoassay the concentrations of carbonic anhydrase III (CA-III, EC 4.2.1.1) in sera from 68 patients with muscular dystrophy, 10 carriers of Duchenne muscular dystrophy (DMD), and 63 patients with other neurological disorders. The values obtained were compared with those for creatine kinase (CK, EC 2.7.3.2). Serum CA-III was strikingly increased in patients with DMD (mean, 274.4 micrograms/L) and congenital (Fukuyama-type) (182.8 micrograms/L) and limb-girdle (203.7 micrograms/L) dystrophies and positively correlated with the activities of CK in patients with DMD. CA-III concentration decreased with the subjects' age and the severity of the disease, similar to the tendency observed between age or severity and the concentration of CK. We found moderately increased CA-III in patients with polymyositis, myotonic dystrophy, amyotrophic lateral sclerosis, spinal progressive muscular atrophy, or Kugelberg-Welander disease and in carriers of DMD.

Adolescent↗
PubMed1990

[Trial for improvement of image quality of chest tomography with computed radiography].

In conventional X-ray tomography, the presence of blurring which is caused by the object outside the focal plane reduces the image quality of the focal plane. With the application of computed radiography for the conventional chest tomography, two kinds of image processing techniques for the elimination of the blurring were examined. As a result, each image processing technique fairly succeeded in improving the image quality.

Humans↗
PubMed1990

[Index of tumor response by in-vivo 31P-MRS--T1 effect as a new predicting index of therapeutic effects].

We observed the metabolism of the Yoshida sarcoma by in-vivo 31P-MRS, using two varieties of repetition time (TR), i.e., TR2s and TR10s. It was measured before the injection of 5FU and 4, 24, 48 hours after the injection. In the each time, PME/ATP ratio, intracellular pH, and TR10/TR2 ratio of PME which reflects the T1 value of PME, were calculated. TR10/TR2 ratio of PME decreased 4 and 24 hours after the injection of 5FU and recovered 48 hours after the injection to the same level before the injection. However decrease of PME/ATP ratio was not observed until 48 hours after the injection of 5FU, when apparent tumor regression appeared. These results suggested that the T1 value of PME decreased prior to the PME changes and when the PME decreased, the intracellular environment of PME recovered to the same state before the therapy. It was considered that the TR10/TR2 ratio of PME offers significant information different from the PME/ATP ratio. It is possible to use the TR10/TR2 ratio as a predicting index for the therapeutic effects.

Animals↗
PubMed1990

Anti-skeletal muscle antibodies in the sera from myasthenic patients with thymoma: identification of anti-myosin, actomyosin, actin, and alpha-actinin antibodies by a solid-phase radioimmunoassay and a western blotting analysis.

We recently reported a strong association between the occurrence of anti-skeletal muscle (SM) antibodies and the presence of thymoma in patients with myasthenia gravis (MG). To further examine the immunoreactivity of MG sera against human muscle antigens, we developed a solid-phase radioimmunoassay (RIA) using purified muscle antigens and a Western blotting analysis in MG sera with high titers of anti-SM antibodies. Our results showed that MG patients with thymoma (thymoma group) had markedly high titers of anti-myosin and anti-actomyosin antibodies than those without thymoma (non-thymoma group). Furthermore, a close correlation was found between titers of anti-SM, anti-myosin and anti-actomyosin antibodies. The antibody titers against actin, alpha-actinin and tropomyosin were all low and did not correlate with titers of anti-SM antibodies. But, significant levels of these three antibodies were found in the thymoma group. By a Western blotting analysis, immunoreactivity of sera from the thymoma group appeared to be predominantly directed against myosin, actin and alpha-actinin.

Autoantibodies↗
PubMed1990

Nationwide survey of HTLV-I-associated myelopathy in Japan: association with blood transfusion.

To study the epidemiology of human T-cell lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in Japan, we conducted two nationwide surveys between October 1986 and March 1989. A total of 710 patients with HAM (definite HAM, 589; probable HAM, 121) were reported. Of the 589 patients with definite HAM, 69% were residents of the areas with the highest prevalence HTLV-I in Japan. To determine the importance of blood transfusion in the pathogenesis of HAM/TSP, we performed a case-control study in the Kagoshima district in southern Japan. Significantly more patients with HAM reported a history of blood transfusion (26/129, or 20%) than did subjects in a health survey of the general population (41/1,290, or 3%; odds ratio = 7.7, p less than 0.001) or than did hospitalized neurological patients (6/119, or 5%; odds ratio = 4.8, p less than 0.001). Furthermore, the cumulative percentages of the intervals between blood transfusion and the onset of the symptoms of HAM fit a lognormal curve, suggesting that transfusion was an important common exposure. Blood transfusion probably transmitted HTLV-I to the patients with transfusion-associated HAM because there was a significant decrease in the number of patients with the transfusion-associated HAM who received blood after implementation of nationwide screening of blood donors in 1986 (p = 0.004). In the first 2 years, screening the blood supply in Japan appears to have decreased the number of reported patients with HAM by 16%.

Humans↗
PubMed1990

Okadaic acid, a potent inhibitor of type 1 and type 2A protein phosphatases, activates cdc2/H1 kinase and transiently induces a premature mitosis-like state in BHK21 cells.

When BHK21 cells synchronized in early S phase were exposed to okadaic acid (OA), an inhibitor of protein phosphatases 1 and 2A, mitosis specific events such as premature chromosome condensation, the production of MPM-2 antigens, dispersion of nuclear lamins and the appearance of mitotic asters were induced, and then disappeared upon further incubation. These mitosis specific events occurred even in the presence of cycloheximide. Within 1 h of exposure to OA, cdc2/histone H1 kinase activity rose 10-fold compared with untreated controls, but returned to the control level upon further incubation. Using antibodies against either p34cdc2 or cyclin B it was found that p34cdc2 complexed with cyclin B was dephosphorylated after OA treatment concomitant with the activation of cdc2 kinase, and that cyclin B was subsequently degraded concomitant with a decrease in cdc2 kinase activity, as in normal mitosis. In contrast, when cells in G1 phase were treated with OA no increase in cdc2 kinase activity was observed. Moreover when cells in pseudo-metaphase induced by nocodazole were treated with OA, cdc2 kinase was inactivated. These results suggest that OA sensitive protein phosphatases control both the activation and inactivation of the p34cdc2 kinase.

Animals↗
PubMed1990

Serum lipid levels in thyroid dysfunction with special reference to transient elevation during treatment in hyperthyroid Graves' disease.

Lipid metabolism was examined in patients with hyper- or hypothyroidism. Compared with corresponding age and sex matched controls, serum total cholesterol (T-chol), low density lipoprotein cholesterol (LDL-chol), phospholipid (PL) and LDL levels were significantly low and free fatty acid (FFA) levels were high with apparently normal triglyceride (TG), very low density lipoprotein (VLDL) and high density lipoprotein cholesterol (HDL-chol) levels in 61 hyperthyroid patients, while T-chol, LDL-chol, TG, PL, VLDL and LDL levels were high with normal FFA and HDL-chol levels in 31 hypothyroid patients. Serum lipid levels were then repeatedly measured in 7 men and 7 women with hyperthyroid Graves' disease before treatment (stage I), just after the patients became euthyroid with anti-thyroid drug (stage II) and more than 2 months after the patients remained euthyroid (stage III). Serum T-chol, LDL-chol, PL and LDL levels were low at stage I, significantly elevated at stage II and then normalized at stage III. Transient but significant elevation of serum TG, VLDL and HDL-chol levels at stage II were also observed in men. Accelerated catabolism and anabolism of lipid has been reported in hyperthyroidism. Transient elevation of serum lipid levels suggests a more rapid improvement in catabolism than in anabolism of lipid in an early stage of the medical treatment for hyperthyroidism.

Adult↗
PubMed1990

Cloning of Xenopus RCC1 cDNA, a homolog of the human RCC1 gene: complementation of tsBN2 mutation and identification of the product.

We isolated a cDNA clone from Xenopus cDNA libraries for the homolog of the human RCC1 gene, which is considered to be a regulator for the onset of chromosome condensation. The cloned Xenopus RCC1 cDNA encoded a protein of 424 amino acids which had the same seven homologous repeated domains of about 60 amino acids as found in human RCC1 cDNA. The overall identity of amino acid sequence between the human and Xenopus RCC1 protein was 76%. Specifically, in the repeated domain the amino acid sequence was highly conserved between both species. The identity of amino acids in this region was 82%. In the N-terminal region, albeit the overall identity was low (35%), some positively charged amino acids were conserved. The transcript for Xenopus RCC1 gene with the length of 2.2-kb was detected in both Xenopus oocytes and cultured somatic cells, A6. The antibody prepared against Xenopus RCC1 protein produced in E. coli recognized 45 and 46 kDa proteins not only in Xenopus oocytes and A6 cells, but also in human and hamster cells. Xenopus RCC1 cDNA complemented the tsBN2 mutation, depending on the amount of its product in transformants. Thus, the RCC1 protein was suggested to regulate the onset of chromosome condensation in the eukaryote from amphibian to mammalian cells.

Amino Acid Sequence↗
PubMed1990

Premature chromosome condensation is induced by a point mutation in the hamster RCC1 gene.

At the nonpermissive temperature, premature chromosome condensation (PCC) occurs in tsBN2 cells derived from the BHK cell line, which can be converted to the Ts+ phenotype by the human RCC1 gene. To prove that the RCC1 gene is the mutant gene in tsBN2 cells, which have RCC1 mRNA and protein of the same sizes as those of BHK cells, RCC1 cDNAs were isolated from BHK and tsBN2 cells and sequenced to search for mutations. The hamster (BHK) RCC1 cDNA encodes a protein of 421 amino acids homologous to the human RCC1 protein. In a comparison of the base sequences of BHK and BN2 RCC1 cDNAs, a single base change, cytosine to thymine (serine to phenylalanine), was found in the 256th codon of BN2 RCC1 cDNA. The same transition was verified in the RCC1 genomic DNA by the polymerase chain reaction method. BHK RCC1 cDNA, but not tsBN2 RCC1 cDNA, complemented the tsBN2 mutation, although both have the same amino acid sequence except for one amino acid at the 256th codon. This amino acid change, serine to phenylalanine, was estimated to cause a profound structural change in the RCC1 protein.

Amino Acid Sequence↗
PubMed1990

Third interim report of the nationwide collaborative study on the long-term effects of bromocriptine in the treatment of parkinsonian patients.

The interim results obtained up to the end of the 3rd year of the multicenter nationwide cooperative study on the long-term effects of bromocriptine in parkinsonian patients are reported. Bromocriptine monotherapy could be continued in approximately 33% of the patients at the mean maintenance dose of 11.4 mg/day. The combined use of bromocriptine (11.1 mg/day) in parkinsonian patients already treated with levodopa had a favorable influence on the long-term side effects of levodopa such as the on-off phenomenon and dyskinesia. The beneficial effects of bromocriptine, levodopa and an early combination on parkinsonian symptoms such as rigidity and tremor remained at the end of the 3rd year. However, the effects of each mode of therapy on another parkinsonian symptom, akinesia, ceased by the end of the 3rd year.

Adult↗
PubMed1990

The diagnosis of mild emphysema. Correlation of computed tomography and pathology scores.

Early and accurate diagnosis of emphysema is said to be invaluable for identification of clinically silent and mild emphysema. Recently, computed tomography (CT) has been much advocated for its efficacy in detailed diagnosis of emphysema, and the results have been compared with the pathology grade of emphysema in resected lung specimens. To assess the ability of high resolution CT scan in detecting and grading mild emphysema, we correlated the high resolution CT scan with the pathology grade of emphysema and the destructive index (DI) of lung specimens from 42 patients undergoing thoracotomy for a solitary pulmonary nodule. The high resolution CT scan and the cut surface of the lung, corresponding exactly to the same plane of the CT scan image, were assessed using the picture-grading system of Thurlbeck and coworkers on a scale of zero to 100. The CT scores for all patients ranged from 12 to 57, with a mean +/- SD of 22.1 +/- 9.6 using 1-mm collimation (n = 35), and from 7 to 46 with a mean +/- SD of 16.5 +/- 8.3 using 5-mm collimation (n = 33). The pathology scores ranged from 10 to 57, with a mean +/- SD of 23.2 +/- 9.8 (n = 42). The DI ranged from 15.4 to 67.1, with a mean +/- SD of 31.4 +/- 10.8 (n = 42). The CT scores using 1-mm and 5-mm collimation correlated significantly with the pathology scores (r = 0.68 and 0.76, respectively, p less than 0.001), and with the DI (r = 0.62 and 0.74, respectively, p less than 0.001). The pathology scores correlated significantly with the DI (r = 0.72, p less than 0.001). We therefore concluded that high resolution CT can help to identify the presence and grading of mild emphysema.

Adult↗
PubMed1990

Antibodies to synthetic peptide (125-148) of the alpha-subunit of human nicotinic acetylcholine receptor in sera from patients with myasthenia gravis.

We measured the amount of antibodies to a synthetic peptide that corresponds to the alpha-subunit residues Lys125-Thr148 of human acetylcholine receptor (AChR) in myasthenic sera. We detected anti-peptide antibodies in 52% (89/171) of the patients with myasthenia gravis (MG), but none in any of the healthy controls. Anti-peptide antibodies should provide a valuable immunologic parameter for the clinical evaluation of MG, but no apparent correlation was observed between the titers of anti-peptide and anti-AChR antibodies.

Autoantibodies↗
PubMed1990

[Database for patients with Duchenne muscular dystrophy].

We had a plan to arrange database for patients with Duchenne muscular dystrophy in Japan. The purpose of this projects will make it possible to design accurate and serial evaluation of patients and conduct therapeutic trial. The items of input are composed of two cards. One card is basic card which fills out mainly patients' basic and genetic informations, the other is course card which records symptoms, muscle strength, joint range of motion, laboratory studies including pulmonary function testing and therapeutic trials. These cards are written by physicians of dystrophic wards in national hospital twice a year and are sent to the statistical coordinating center of database. On the other hand outputs include annual report and optional output which are requested by each investigator. Now 519 basic cards and 1026 course cards have completed. In this paper we tried to output about some results of the data obtained. These outputs include the age of initial gait and difficulty in walking, mean muscle strength by functional grade and the change of muscle strength during the administration of some drugs.

Adolescent↗
PubMed1990

[Eight cases of intracranial arteriovenous malformations treated by conventional radiation therapy].

We conducted radiotherapy in 8 cases of intracranial arteriovenous malformation that had difficult embolectomy and other surgery from 1983 to October, 1988. The results in 6 cases of dural arteriovenous malformation at the cavernous sinus were "marked effect" in 4 cases, "relapse" in 1 case, and "no effect" in 1 case. One case of dural arteriovenous malformation at the sigmoid venous sinus demonstrated only slight irradiation effect. No irradiation effect was observed in 1 case of cerebral arteriovenous malformation.

Adult↗