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H Murayama

Publications and source records attributed to H Murayama.

At least 91 records · Page 5Linked to original sources
PubMed1995

On the mechanism of preferential incorporation of dAMP at abasic sites in translesional DNA synthesis. Role of proofreading activity of DNA polymerase and thermodynamic characterization of model template-primers containing an abasic site.

DNA polymerase preferentially incorporate dAMP opposite abasic sites (A-rule). The mechanism of the A-rule can be studied by analyzing three dissected stages of the reaction including (i) initial nucleotide insertion, (ii) proofreading excision of the inserted nucleotide and (iii) extension of the nascent primer terminus. To assess the role of the stage (ii) in the A-rule, kinetic parameters of the proofreading excision of primer terminus nucleotides opposite abasic sites were determined using E.coli DNA polymerase I Klenow fragment. The relative efficiency of the excision (Vmax/Km) revealed that removal of A was the least favored of the four nucleotides, but the differences in the efficiencies between excision of A and the other nucleotides was less than 2-fold. In addition, in an attempt to reconcile kinetic data associated with the stage (i) or (ii), the differences in free energy changes (delta delta G degrees) for the formation of model template-primer termini containing XN pairs (X = abasic site, N = A, G, C or T) were determined by temperature dependent UV-melting measurements. The order of delta delta G degrees was XG > XA = XC > or = XT, with delta delta G degrees being 0.5 kcal/mol for the most stable XG and the least stable XT. Based on these data, the role of the stage (ii) and energetic aspects of the A-rule are discussed.

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PubMed1995

Preoperative diagnosis of a small, depressed rectal cancer complicating ulcerative colitis. Report of a case.

PURPOSE: This study was designed to clarify the importance of detecting small, depressed colorectal cancer complicating ulcerative colitis. METHODS: A 39-year-old Japanese male, who had an 18-year history of left-sided ulcerative colitis, was admitted to Fukuoka University Hospital for further evaluation of his colitis. Colonoscopy with a dye spraying method clearly revealed a small, depressed lesion and flat plaque-like lesions in the rectum. Biopsies taken from a depressed lesion and plaque-like lesions revealed a signet-ring cell carcinoma and dysplasia, respectively. Total colectomy was performed. RESULTS: Sections from the depressed rectal lesion, measuring 7 x 8 mm in size, revealed a signet-ring cell carcinoma that diffusely invaded the muscularis propria. Lymph node metastasis was evident. Flat plaques and mucosa around the depressed lesion were positive for dysplasia. CONCLUSION: This is the first report of a case of small, depressed rectal cancer complicating ulcerative colitis diagnosed by preoperative colonoscopy. To improve outcome of colonoscopic surveillance in ulcerative colitis, detecting such small, depressed lesions are important, and colonoscopy with a dye spraying method would be useful in detecting them.

Adult↗
PubMed1995

[Long-term evaluation of the Carpentier-Edwards pericardial bioprosthesis].

Long-term follow up results of valve replacement with Carpentier-Edwards pericardial bioprosthesis were analysed. From April 1985 to March 1994, a total of 99 bioprostheses were implanted in 92 patients. Aortic valve replacement was performed in 27, mitral valve replacement in 43, combined aortic-mitral valve replacement in 7 and tricuspid valve replacement in 15 patients. The actuarial survival rates at 9 years were 84% (aortic), 59% (mitral), 69% (aortic-mitral) and 76% (tricuspid) respectively. One patient sustained a thromboembolic event after mitral valve replacement, however, none of that complication occurred after aortic or tricuspid valve replacement. Two patients with mitral valve replacement required reoperation because of structural deterioration after 8 years. Five cases of bioprosthetic infection encountered, and three died. Actuarial freedom from overall valve-related complications at 9 years was 97% for aortic, 72% for mitral and 100% for tricuspid valve replacement respectively. There was no structural deterioration of the aortic and tricuspid valve. Actuarial freedom from structural deterioration of the mitral valve was 84% at 9 years. We conclude that the Carpentier-Edwards pericardial bioprosthesis has low incidence of valve related complication within the 9 years time frame of this study.

Adult↗
PubMed1994

[Monitoring of electroencephalogram during the operation under the extracorporeal circulation].

Generally speaking, it is difficult to know the occurrence of brain complication until the patient becomes awake from anesthesia. But if we can detect the occurrence of of brain complication during the operation, we can start its therapy even during the operation. In order to detect the occurrence of brain complication during the operation under extracorporeal circulation (ECC), we monitored intraoperative electroencephalogram (EEG). Since June 1992, forty-two patients were operated on using ECC. Usual ECC was applied in 39 cases (Group-A), and circulatory arrest with retrograde cerebral perfusion was applied in remaining three cases (Group-B). We studied the amplitude of EEG using actual value (by Fujimori method), and compressed EEG acquired by slow-paper-feed recording. In terms of the frequency of EEG, we studied compressed spectral array (CSA). In Group-A, there was no brain complication identified after operation. Actual values of amplitude were 23 +/- 4.0 microV (before ECC), 19 +/- 4.0 microV (during ECC), 23 +/- 4.9 microV (after ECC). There was a significant decrease (p < 0.001) of amplitude during ECC compared with that before ECC. The ratio of amplitude during ECC to that before ECC (D/B ratio) was 0.82 +/- 0.16. The ratio of amplitude after ECC to that before ECC (A/B ratio) was 1.01 +/- 0.15. According to compressed EEG, it was observed that the amplitude changes following the up-down of esophageal temperature. In CSA, influence of esophageal temperature on the power spectrum of alpha and delta wave band was recognized. In Group-B, there was one brain complication identified after operation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Creatine kinase isoenzyme BB increased in serum and tumor tissue of patients with giant cell tumor of bone.

Increased creatine kinase isoenzyme BB (CK-BB) has been observed in sera from patients with brain injuries and occasionally in sera from patients with malignancy. We report here that, in two patients with giant cell tumor of bone (GCT), preoperative serum CK-BB increased to approximately 20 and 90 U/L, but in postoperative serum the CK-BB decreased to normal values. That the tumors contained CK-BB was indicated by electrophoretic analysis and immunohistochemical staining. Furthermore, serum CK-BB was detectable in five additional cases of GCT and in cultured tumor cells from a patient with GCT by an electrophoretic method. These results suggest that CK-BB may be a marker for GCT.

Adult↗
PubMed1994

[Relationships between serum lipid peroxide level (serum TBA level) and smoking, alcohol drinking, food frequency, serum vitamin C and E in subjects with multiphasic screening].

Relationships between serum thiobarbituric acid (TBA) level and smoking, alcohol drinking, differences in food intake with alcohol drinking, serum vitamin C (VC) and E (VE) were studied in 283 non-treated men (aged 20-69 years) who visited a human dock conducted in an urban area of Hyogo prefecture in 1989-1991 (annually May-July). The results were as follows: 1. An effect of smoking on serum TBA level was not observed. 2. The subjects were divided into three groups according to weekly sake intake levels, i.e., non-drinkers including ex-drinkers (ND), mild drinkers (MD, weekly sake intake: < or = 1260 ml), and heavy drinkers (HD, > 1260 ml). The serum TBA level of HD, but not of MD, was significantly higher than that of ND. 3. Serum TBA level had significant positive correlations with age, GPT, gamma-GTP, TC (total cholesterol), TG (triglycerides), PL (phospholipids), total serum lipids (TLP, i.e., TC+TG+PL), VE, eicosapentaenoic acid (EPA, C20:5) and docosahexaenoic acid (DHA, C22:6), but had no significant correlations with VC and VE/TLP. 4. The subjects (N+M) D, which included ND and MD, and those of HD were divided respectively into three groups according to weekly food intake levels, i.e., non-intake group (NF), low frequent intake group (LF, 1-3 days/week), and high frequent intake group (HF, > or = 4 days/week). The fish intake level of HD was significantly higher than that of (N+M) D, while the intake levels of vegetables, fruits and soft drinks of HD were significantly lower than those of (N+M) D. 5. Serum TBA level, GOT, GPT, gamma-GTP, TG, PL, TLP, VE, EPA and DHA of HD were significantly higher than those of (N+M) D. On the other hand, VC of HD was significantly lower than that of (N+M) D. 6. When the subjects of (N+M) D were divided into three groups according to weekly fish intake levels as mentioned above, serum TBA level, EPA and DHA of HF in (N+M) D were significantly higher than those of NF in (N+M) D. 7. Serum TBA level of HD in non-fish intake group was significantly higher than that of (N+M) D in the same group. These results suggest that increased serum TBA level in HD is closely related to the increased intake frequency of fish in addition to the effect of alcohol drinking.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[A case report of successful management of intraoperative aortic dissection during aorta-coronary bypass and aortic valve replacement].

A 70-year-old woman underwent aortic valve replacement and coronary artery bypass surgery with a saphenous vein graft for aortic regurgitation and 99% stenosis in the right coronary artery. During the period of weaning from the cardiopulmonary bypass enlargement of the ascending aorta and bleeding from the suture line were observed. The intraoperative diagnosis of ascending aortic dissection (DeBakey type I) was made with transesophageal and transthoracic echocardiography. Cardiopulmonary bypass was reinstituted and the patients was cooled to 20 degrees C. Under circulatory arrest and continuous retrograde cerebral perfusion through the superior vena cava the intimal tear at the point of infusion cannula was removed and the ascending aorta was reconstructed by direct suture bolstered with Teflon felt strips. Following completion of the repair no further dissection was seen, and the patient was successfully weaned from cardiopulmonary bypass. There were no signs of neurologic complications. Although intraoperative aortic dissection is uncommon, it can be a fatal iatrogenic complication of cardiac operations. Prompt recognition and surgical repair of the injuries are essential to achieve a successful outcome. The combination of transesophageal echocardiography and transthoracic echocardiography permits the immediate diagnosis of aortic dissection. And it is suggested that continuous retrograde cerebral perfusion through the superior vena cava protects the brain for 52 minutes of cerebral circulatory arrest at the lowest nasopharyngeal temperature of 18.7 degrees C. This technique is simple, and required neither special preoperative preparation or special equipment, so that it is suitable especially for intraoperative aortic dissection such as this case.

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