Biomedical subjects
Publications and source records attributed to F Yoneda.
Using CPG support linked with 5-deazaflavin, the 5-deazaflavin modified oligodeoxynucleotides at 3'-end(ODN-dF1) were synthesized. The thermal stability of the duplex of ODN-dF1 with its complement was higher than that of oligonucleotide linked to 5-deazaflavin at 5'-end internucleotide linkage.
6-Phenyl analogs of toxoflavin (1-methyl-6-phenylpyrimido[5,4-e]-1,2,4-triazine-5,7(1H,6H)-diones ) (7a--f) and their 4-oxides (8a-f) were synthesized by nitrosative or nitrative cyclization of the aldehyde hydrazones (6a-f) of 6-(1-methylhydrazino)-3-phenyluracil (5). Both sets of compounds, 7a-f and 8a-f, gave the corresponding 1-demethyl derivatives (10a-f) upon treatment with nucleophiles such as dimethylformamide (DMF) and acetic acid under heating. The activities of toxoflavins (1a-e), toxoflavin 4-oxides (3a-e) and their 6-phenyl analogs (7a-f and 8a-f) against a variety of bacterial and fungal strains were examined. Most of the compounds showed strong inhibitory activities against gram-positive bacteria. Among the compounds, 1c, 1d, 1e, and 3c exhibited the strongest inhibitions of Micrococcus lutea (0.5 micrograms/ml minimal growth-inhibitory concentration) and Staphylococcus aureus 4R (1 microgram/ml), as well as Bacillus subtilis and Staphylococcus aureus (1-2 micrograms/ml). Most of the compounds had strong antifungal activity (2-100 micrograms/ml minimal growth-inhibitory concentration) against Candida albicans and Saccharomyces cerevisiae.
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Bromohydrins (2, 3, 4, and 5), oxidatively damaged products of thymine bases, were repaired on exposure to sunlight, heat, and/or some reagents to regenerate the thymine bases. A radical mechanism is proposed for the repair reaction with sunlight and heat. A hypothesis concerning the biological significance of thymidine in deoxyribonucleic acid is presented.
Bromohydrins (12, 13, and 14), which were oxidatively damaged products of thymidine nucleotides, were repaired by the action of sunlight (2700 lux) or heat via a radical mechanism to regenerate the original nucleotides (8,9, and 10). A significant effect of 3',5'-phosphate linkage on the repair reactions to natural type of thymidine nucleotide was proposed.
Several viologen-tagged oligodeoxynucleotides in the form of covalent linkage at the specific site of the phosphorous backbone were synthesized and characterized. Incorporation of viologen molecules was confirmed by the 31P-NMR, 20% PAGE analysis, enzymatic degradation, and uv, ESR spectra of the derived cation radical. The Tm values and CD spectra of the modified strands with their complementary strands indicate that the introduction of the viologen molecule via linker arm causes no significant perturbation in duplex structure.
Oligonucleotides covalently linked to isoalloxazines via polymethylene linker were synthesized and characterized. The thymidine decamer having a primary aminoalkyl group at the 5'-end of internucleotide linkage was coupled with the activated ester of isoalloxazine in liquid-phase. The interaction of the flavin modified thymidine decamers with polydA was investigated by using spectrophotometric method.
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We report 42 patients with urothelial tumors in upper tract admitted to our hospital between August, 1969 and August, 1988. The patients consisted of 33 males and 9 females; their ages ranged from 42 to 85 years with a mean of 66.2 years. Total nephroureterectomy with bladder cuff resection was employed as the surgical method in 24 cases, total nephroureterectomy without bladder cuff resection in 11 cases, total nephroureterectomy with total cystectomy in 2 cases and partial ureterectomy only in 2 cases. Tumor lesions had a positive correlation with grade and stage. The survival rate for all the patients at 1, 3 and 5 years was 76.0, 58.8 and 54.6%, respectively, as measured by the Kaplan-Meier's method. The prognosis of the patients with renal pelvic tumor and ureter tumor was dependent upon grade, stage and intravascular tumor-emboli. Vesical recurrence was observed in 10 cases and found frequently in low grade tumor and/or low stage tumor cases. The frequency of vesical recurrence was not positively correlated with cuff resection The 5-year survival rate was not different between the patients with vesical recurrence and those without vesical recurrence.
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Bromohydrins, which were damaged products of thymidines (2, 3, and 4), were repaired with sunlight of heat via a radical mechanism to regenerate the thymidines. A hypothesis for the biological significance of thymidine in DNA is presented.
Bromohydrins, which were damaged products of thymidines (2, 3, and 4), were repaired with sunlight or heat via a radical mechanism to regenerate the thymidines. A hypothesis for the biological significance of thymidine in DNA is presented.
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The riboflavin analog 10-(4'-chlorophenyl)-3-methylflavin was found to have significant activity against Plasmodium vinckei vinckei when administered orally and parenterally; it was active against P. falciparum in culture. It inhibited mouse erythrocyte glutathione reductase in a dose-dependent manner. When administered orally, 5-deazariboflavin was not active in vivo although it has been shown to have activity against P. falciparum in vitro.
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The results of the operation were analyzed statistically in 68 patients who underwent suprapubic prostatectomy for benign prostatic hypertrophy from 1979 to 1985. The patients were between 59 and 86 years old with a mean age of 72.0 years. The average operation time was 63 minutes and average blood loss during the operation was 292 g. The average weight of enucleated prostate was 32.6 g. Acute epididymitis and urine leakage from the wound were the most frequent postoperative complications. There were no postoperative deaths. The average postoperative admission period was 25.6 days. Histological examination of the specimens revealed occult carcinoma in 2.9% of the patients.
Two cases of ureteral inverted papilloma are reported. Case 1: A 48-year-old male had asymptomatic gross hematuria and filling defect of left middle ureter on intravenous pyelography. Segmental resection of ureter was performed. The specimen was a 1 cm polypoid lesion with histologic features resembling "multifocal bud-like proliferation", which was reported as the initial stage of the inverted urothelial tumor by Kunze et al. Case 2: A 64-year-old female with asymptomatic gross hematuria and complete obstruction of left middle ureter on ante- and retrograde pyelograms. Total nephroureterectomy was performed. A 4 cm lobulated and pedunculated lesion with histologic features of typical inverted urothelial papilloma was resected. Twenty-one cases of ureteral inverted papilloma in the literature, including our cases, are analyzed.
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