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Biomedical subjects

M Miyata

Publications and source records attributed to M Miyata.

At least 325 records · Page 18Linked to original sources

[Ocular manifestations in mitochondrial DNA abnormalities].

We reviewed the ophthalmological and genetic aspects of mitochondrial diseases, a group of multisystem disorders that involve the function and morphology of mitochondria and affect multiple organs including skeletal muscle, central nervous system, heart, and ear. Disease-specific deletion or point mutation of mitochondrial DNA (mtDNA) has been clarified in many clinical entities of the group, and we confirmed that the ocular manifestations, including chronic progressive external ophthalmoplegia, blepharoptosis, retinochoroidal degeneration and optic nerve atrophy, develop in association with either deletion or point mutation of mtDNA. Together with a review of the literature, we describe a case of myoclonic epilepsy and ragged-red fibers with mutation at mtDNA 8344 and insidious bilateral optic atrophy. We also describe cases of myotonic dystrophy which had an abnormal expansion of CTG repeat of chromosome 19 protein kinase gene and showed retinochoroidal degeneration and mitochondrial morphological changes.

Adult↗

[A successful case of omentopexy for bronchopleural fistula and empyema after right pneumonectomy].

A 59-year-old male was performed right pneumonectomy with R 2 b lymph node dissection and intercostal muscle flap to the bronchial stump for squamous cell carcinoma of right upper lobe of the lung (cT 2 N 2 M 0-stage III A). But four weeks later bronchial stump was suddenly reopened and he developed empyema. Omentopexy for bronchopleural fistula (15 x 11 mm in size) and thoracoplasty for empyema was performed. Bronchoscopically the fistula is 2 mm in diameter and reepithelization is started around the fistula at 14 POD and the fistula is completely closed and covered with reepithelized mucosa without inflammation at 100 POD. We think omentopexy for bronchopleural fistula after pneumonectomy is very effective procedure, so we should be considered this method at first. But if the fistula is accompanying empyema as our case thoracoplasty should be added.

Bronchial Fistula↗

[Traumatic middle cerebral artery occlusion].

A 16-year-old boy developed motor aphasia and right hemiplegia after head trauma caused during Rugby football club activity. About 2 hours after trauma, these neurological deficits improved dramatically. CT scan on admission revealed no abnormal finding. But, on the next day, CT scan revealed an irregular low density area at the left basal ganglia. Cerebral angiography showed a slight narrowing at the left carotid siphon, severe stenosis at M1 portion of the left middle cerebral artery with vasospasm of its distal branches and occlusion of the left anterior temporal artery. The extracranial portion of the left internal carotid artery was intact. Clinically, the patient recovered from the right hemiparesis almost fully and was discharged after 1 month with mild dyscalculia. Three months later, follow-up angiography disclosed stenosis of the left M1 portion but the narrowing of the carotid siphon and vasospasm of the peripheral branches of the middle cerebral artery had been normalized, and the anterior temporal artery was recanalized. The pathogenesis of the occlusion is classified into 4 causes, 1) embolism from internal carotid artery, 2) vasospasm, 3) thrombus formation, 4) dissection. However, the demonstration of this by angiography is difficult. In our case, the injury of the intracranial portion of the internal carotid artery, which caused the intimal injury, spasm or thrombus formation, might have happened and resulted in embolisation and recanalization of the middle cerebral artery.

Adolescent↗

Comparison of the conserved region in the dnaA gene from three mollicute species.

Polymerase chain reaction was carried out to amplify the conserved region (789 bp in the case of Mycoplasma capricolum) of the dnaA gene (1350 bp in the case of M. capricolum) of 15 representatives of the class Mollicutes using degenerate oligonucleotide primers. The dnaA gene fragments were amplified from M. mycoides subsp. capri, Spiroplasma apis and S. citri. The amino acid sequences deduced from the nucleotide sequences of the amplified fragments showed very low similarities to those of the corresponding regions of four walled bacteria. The values of similarity between any two of the three mollicute species were lower than those between any two of the four walled bacteria.

Amino Acid Sequence↗

Isolation and expression of a cDNA encoding a male-specific rat sulfotransferase that catalyzes activation of N-hydroxy-2-acetylaminofluorene.

A cDNA (ST1C1 cDNA) encoding a N-hydroxyarylamine sulfotransferase (HAST-I) was isolated from a liver cDNA library of a male adult rat and was expressed in COS-1 cells. ST1C1 cDNA (1363 base pairs) encoded a protein of 304 amino acids with a molecular mass of 35,768 daltons, which shared 50.7 and 46.1% sequence identity with rat aryl (ST1A1 (PST-1)) and estrogen (rOST) sulfotransferases, respectively. N-terminal amino acid sequences of three digested polypeptide fragments of HAST-I were completely identical with two portions of the ST1C1 amino acid sequence. The profile of age- and sex-related expression of ST1C1 mRNA was quite consistent with changes in the sulfating activity of N-hydroxyarylamine and HAST contents in rat livers. ST1C1 expressed in COS-1 cells catalyzed a sulfation of N-hydroxy-2-acetylaminofluorene (N-OH-AAF) at a rate of 4.98 nmol/mg of protein/min and mediated PAPS (3'-phosphoadenosine-5'-phosphosulfate)-dependent DNA binding of N-OH-AAF. Although ASTIV was believed to be responsible for the activation of N-OH-AAF, ST1A1 encoding an arylsulfotransferase ASTIV, showed only a marginal activity in a sulfation and covalent binding of N-OH-AAF. These data clearly indicate that ST1C1 cDNA codes a new form of a male-dominant sulfotransferase (HAST) responsible for the bioactivation of N-hydroxyarylamines in rat livers.

Amino Acid Sequence↗

Mapping of replication initiation site in Mycoplasma capricolum genome by two-dimensional gel-electrophoretic analysis.

The homolog of the dnaA gene, which has been reported to be present in the vicinity of the initiation site of replication in the genome of Mycoplasma capricolum (M.Miyata, L.Wang, and T.Fukumura, J. Bacteriol. 175: 655-660, 1993) was mapped precisely. A 9540-bp region containing the dnaA gene was cloned and the entire region was sequenced with the exception of a previously reported region of 2517 bp (Fujita, M.Q., Yoshikawa, H. and Ogasawara, N. Gene 93: 73-78, 1992). The organization of the 9540-bp region was compared with that of corresponding regions in other bacteria. The arrangement and directions of rnpA, rpmH, dnaA, dnaN were conserved, but no other open reading frames were found that were homologous to those that are commonly found around dnaA genes in other bacteria. The directions of movement of the replication fork around the dnaA gene were analyzed by neutral/alkaline two-dimensional gel electrophoresis. The forks developed in a 1569-bp region that consisted of the dnaA structural gene and its downstream non-coding region, and then they proceeded bidirectionally.

Amino Acid Sequence↗

Prognostic value of DNA ploidy in squamous cell carcinoma of esophagus. Analyzed with improved flow cytometric measurement.

BACKGROUND: The prognostic value of flow cytometric DNA analysis on paraffin-embedded tumor samples has been controversial in esophageal cancer. To clarify its true significance, the authors developed an improved method that excludes the possibility of contamination by lymphocytes in tumor sample. METHODS: Single nuclear suspension was prepared from paraffin-embedded samples on 103 patients with squamous cell carcinoma of the esophagus. Both DNA content and nuclear size were simultaneously measured by flow cytometry on 30,000 nuclei, and contaminated lymphocyte nuclei were eliminated from the data by optimal gating. Correlation between DNA ploidy and postoperative survival was examined. RESULTS: Analysis using a flow cytometric cell sorter showed that the frequency of tumor cells in the lymphocyte-reducing gating fraction (LGF) was significantly higher than that in the conventional nongating fraction (NGF). LGF analysis showed aneuploid peaks in 58 patients (56.3%), but NGF analysis showed aneuploid peaks in only 38 patients. LGF analysis revealed that the aneuploid tumors had higher histologic grading (P < 0.05) and worse survival rate (P < 0.01) compared with diploid tumors. However, conventional methods could not detect this difference. CONCLUSIONS: Flow cytometric analysis gating by nuclear size may be helpful to detect aneuploid peaks, and for predicting prognosis of patients with squamous cell carcinoma of esophagus.

Adult↗

[Japanese translation of profile of mood states (POMS)--interpretation of the fifty-six items of mood factors and their application in a manufacturing automotive parts factory].

As in Europe and the USA, POMS is now going to be widely used in the area of occupational health in Japan. However, the Japanese translation of POMS is still not well established. Therefore, in this study, we translated the POMS into Japanese, and using 261 medical students in their last three years of study, we analyzed whether the fifty-six items of the mood factors of POMS are correctly or differently interpreted compared with the classified mood states in the original POMS. The number of the items, differently interpreted at a higher frequency than 20% among the students, was about 20 on the average of three years. Many of the items fell under the heading of "depression-dejection" and "tension-anxiety". The number of items, differently interpreted at a lower frequency than 5% among the students, was about 15 on the average of three years. Many of these items belonged to "vigor". The Japanese translation of POMS was applied to 106 workers engaged in manufacturing automotive parts. Among male and female workers exposed to organic solvents, a positive correlation (P < 0.05) was found between the urinary hippuric acid level and the score of "anger-hostility". Negative correlations (P < 0.05-0.001) were found between the age and each score of "tension-anxiety", "depression-dejection", "anger-hostility", "fatigue" and "confusion". However, no significant difference in the score of any mood factors of POMS was found between the group of sixty-one workers exposed to organic solvents and the group of forty-five workers unexposed.(ABSTRACT TRUNCATED AT 250 WORDS)

Affect↗

Prognostic significance of transforming growth factor-alpha in human esophageal carcinoma. Implication for the autocrine proliferation.

BACKGROUND: The authors recently used immunostaining to demonstrate that patients with epidermal growth factor receptor (EGFR) overexpression have poor survival after surgery. However, the clinical significance of transforming growth factor (TGF)-alpha, one of the ligands of EGFR, has not been demonstrated in esophageal carcinoma. METHODS: Immunohistochemical study for TGF-alpha and EGFR was performed on 57 esophageal squamous cell carcinomas using monoclonal antibodies. RESULTS: TGF-alpha expression was positive in 35% of the tumors, and EGFR overexpression, defined as stronger staining in cancer cells than in normal epithelium, was positive in 43% of the tumors, according to the authors' arbitrary criteria. The incidence of TGF-alpha positivity was relatively higher in patients with the EGFR overexpression (EGFR+) than in the patients with non-overexpression (EGFR-). The survival rate was significantly lower in patients with TGF-alpha(+) than in those with TGF-alpha(-) (P < 0.01) and in patients with EGFR(+) than in patients with EGFR(-) (P < 0.01), respectively. Considering TGF-alpha and EGFR expression simultaneously, the survival rate of the patients with TGF-alpha(+)/EGFR(+) tumors was the lowest of the four subgroups, with statistically significant differences noted. These relationships between the immunoreactivities and survival curves were observed in the analysis within patients with node-positive disease. In addition, a multivariate statistical analysis demonstrated that TGF-alpha was the only significant variable, whereas EGFR and nodal status provided no additional information regarding postoperative survival. CONCLUSION: The results presented suggest that TGF-alpha may act as an autocrine growth factor through hyperproducing EGFR and that its expression and EGFR overexpression may prove useful as a valuable prognostic indicator for patients with esophageal carcinoma.

Carcinoma, Squamous Cell↗

Pancreatic ductal cell carcinoma producing pancreatic elastase 1.

The elevation of plasma pancreatic elastase 1 in patients with pancreatic cancer is caused by concomitant pancreatitis. There is no report that pancreatic ductal cell carcinoma tissue itself produced elastase 1. A 54-year-old woman underwent total pancreatectomy for pancreatic ductal cell carcinoma. Her plasma elastase 1 level subsequently decreased from the preoperative value of 406 ng/dl to values ranging between 96 ng/dl and 119 ng/dl, until 6 months after the operation, when it began to increase gradually to a maximum of 300 ng/dl in association with local recurrence and hepatic metastasis. Immunohistochemical staining of elastase 1 was positive in the primary tumor resected at operation as well as in the locally recurrent and hepatic metastatic tumors obtained at autopsy. These findings suggested that elastase 1 was produced by the tumor cells in this patient. This is the first case in which pancreatic ductal cell carcinoma cells produced elastase 1.

Adenocarcinoma↗

Protocol for the technique of orthotopic liver transplantation in the rat.

Orthotopic rat liver transplantation (OLT) has been generally accepted as an excellent model for the analysis of pathological, physiological, and immunological aspects related to organ transplantation. However, many researchers require a long training period to achieve a high success rate using this major surgical procedure on small animals. We therefore developed a protocol for learning rat OLT. It is recommended, initially, that the heterotopic heart transplantation (HHT) model be used to master the cuff technique, since this technique is similar to that in OLT and leads to an understanding of another organ transplantation technique. For beginners who advance beyond the HHT step to OLT but cannot finish the anhepatic phase within 30 min, we recommend the use of portosystemic-shunted rats as recipients. These animals have had their spleens transposed subcutaneously more than 3 weeks before use. The use of these modifications and this training program makes it possible to master the techniques and to achieve a high success rate with a short training period.

Animals↗

Gastric inhibitory polypeptide secretion after gastrectomy in patients with diabetes mellitus.

Gastric inhibitory polypeptide (GIP) secretion after distal gastrectomy was compared between patients with diabetes mellitus (DM-group) and patients with normal glucose tolerance (N-group). GIP secretion in the DM-group was significantly greater in the early postcibal response period, but less in the late postcibal response period after gastrectomy, the total secretion of GIP being less after gastrectomy than before in this group. In the N-group, both the early and total postcibal responses of GIP were greater after gastrectomy than before. Moreover, the early and total postcibal secretions of GIP after gastrectomy were less in the DM-group than in the N-group. These findings suggest that GIP secretion in diabetics becomes insufficient after gastrectomy.

Adult↗

Radical resection of primary malignant melanoma of the gallbladder with multiple metastases: report of a case.

We present herein an usual case of primary malignant melanoma of the gallbladder in a 51-year-old man in whom an exploratory laparotomy for melena revealed six malignant melanoma lesions located in the gallbladder, main pancreatic duct, stomach, duodenum, jejunum, and a mesenteric lymph node. Total pancreatectomy was performed and histologically, junctional activity was seen only in the gallbladder, suggesting that this was the primary site. No melanotic lesions were found on the skin or eyes. The metastases to the main pancreatic duct and gastrointestinal tract appeared likely to have occurred as a consequence of the mucosal dissemination of the tumor cells shed into the bile. The post-operative course was uneventful and combined chemotherapy was administered for 16 months. No new metastatic lesions were found until 21 months postoperatively, when metastases were detected in the brain and thoracic spinal cord. These metastatic tumors were removed surgically, but the patient died from cerebral disturbance 26 months after the initial operation. Thus, we consider that aggressive surgical therapy was effective for extending the survival time and improving the quality of life of this patient.

Adult↗

Lidocaine metabolite formation as a measure of perioperative liver function.

In order to determine whether lidocaine metabolism, as the formation of monoethylglycinexylidide (MEGX), could be used as a quantitative index of perioperative liver function, serum levels of MEGX in 31 surgical patients were measured and compared with the results of conventional liver function tests. A significant correlation was found between the values of MEGX and ICGR15 in 20 of the 31 patients. The values of ICGR15 were lower than 20% in patients whose MEGX values were above 60 ng/ml and 20% or higher in those with MEGX values of lower than 60 ng/ml. There was also a significant correlation between MEGX values and antithrombin III values, and between MEGX values and the postoperative maximum levels of aspartate aminotransferase. However, no correlation was found between MEGX values and other preoperative conventional liver function tests in any of the 31 patients. We suggest that a cut-off MEGX value of 60 ng/ml be used as an indicator for satisfactory preoperative liver function. MEGX formation could be a useful prognostic index for patients who have undergone surgical procedures for liver disease, and employed as a quantitative assessment of perioperative liver function.

Adult↗