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Biomedical subjects

K Isono

Publications and source records attributed to K Isono.

At least 361 records · Page 20Linked to original sources

Epiderstatin, a new inhibitor of the mitogenic activity induced by epidermal growth factor. II. Structure elucidation.

The structure of a novel antibiotic, epiderstatin, was determined as 4-[3-((Z)-3,5-dimethyl-2-oxopiperidin-6-ylidene)-2-oxopropyl]-2, 6-piperidinedione by spectroscopic analyses of 1H NMR, 13C NMR, 1H-1H correlation spectroscopy (COSY), 13C-1H COSY, heteronuclear multiple bond correlation spectroscopy, UV and IR spectra. The antibiotic belongs to the glutarimide antibiotics, however, the characteristic feature of epiderstatin is that it has a piperidone ring instead of a cyclohexanone ring.

Antibiotics, Antineoplastic↗

Biosynthesis and 13C NMR assignment of cytovaricin, a neutral macrolide antibiotic.

13C NMR analysis of 13C-labeled cytovaricin which was obtained by feeding sodium [1-13C]-, [2-13C]-, and [1,2-13C]acetates, [1-13C]- and [3-13C]propionates, [1-13C]isobutyrate and [methyl-13C]methionine to cultures of Streptomyces diastatochromogenes showed that the aglycone of cytovaricin is derived from nine acetate units, six propionate units and one isobutyrate unit and the methoxy group at C-3' of cymarose moiety is derived from the methionine-S-methyl group. The 13C NMR spectra of 13C-labeled cytovaricins which were obtained from feeding experiments allowed the complete assignment of the 13C NMR spectrum of cytovaricin.

Anti-Bacterial Agents↗

[Lithotomy of bile duct stones by flash-lamp-pumped dye laser].

Laser therapy for bile duct stones, such as the non-contact beam treatment using continuous wave of Nd:YAG laser or contact beam treatment using ceramics rod, has been done in our institution from 1980. As a result, the ratio of complete lithotomy has been increased from 31/47 (66%) to 66/71 (93%). Recently, we had a opportunity to use the Lasertripter by Candera Corp., which was devised for urinary stones. It beams pulse wave to crush stones. The effectiveness of this new laser lithotripsy is different according to the kind of the stones, but it is better than that of conventional YAG laser. Furthermore, as this method can be used with thin fiberscope, this method is more effective to peripheral intrahepatic stones than YAG laser.

Aged↗

[Benefits and risks associated with dissection of three regional lymph nodes (bilateral cervical, thoracic and abdominal) in thoracic esophageal carcinoma].

To obtain curability safely, we have employed dissection of three regional lymph nodes (the bilateral cervical, thoracic and abdominal lymph nodes) since 1983. The subjects were 111 (three regional group) of 158 patients with thoracic esophageal carcinoma operated on our department till 1988. When compared to 207 patients treated during the period from 1973 to 1982 (control group), the background factors of the subjects revealed that the three regional group included more patients with advanced carcinoma and more elderly patients over 70 years of age. Operative results were more favourable in the three regional group (5.3% vs 2.7%), although mean operative time was longer (5 hrs and 2 min vs 8 hrs and 38 min) and mean blood loss was higher (1,098ml vs 1,407ml). Moreover, the incidence of recurrent nerve paralysis was higher. Overall 5-year survival was 20.4% vs 22.3%, showing no significant difference. However, when stage distribution is taken into consideration, results in the three regional group may be regarded as improved. After dissection of the three regional lymphnodes, the pattern of lymph node metastasis of thoracic esophageal carcinoma has been made clearer to give useful information on the site in which further dissection of lymph node is required.

Abdomen↗

[Detection of ras gene mutations of pancreatic tumors by polymerase chain reaction and direct sequencing method].

Ras genes (H-,K-,N-ras) are converted to active oncogenes by point mutations occurring in either codon 12, 13 or 61. We analyzed 19 pancreatic tumors (formalin fixed paraffin embedded tissue) of these codons by a method to directly sequence nucleotides around codons 12/13 and 61 of the three ras genes, using polymerase chain reaction and direct sequencing method. Of 19 pancreatic tumors, all 17 duct cell carcinomas involving 2 mucous producing pancreatic cancers had point mutations of the K-ras codon 12, but 2 islet cell tumors had ano point mutation around codons 12, 13, 61 of the three ras genes. Extremely high incidence of ras gene mutation may be relevant to certain pathogenesis of pancreatic cancers.

Base Sequence↗

[Perioperative water and electrolyte metabolism and its abnormalities in aged patients].

The number of aged surgical patients is increasing due to the increase of aged people in the general population. Aged surgical patients above 65 years of age constituted about 30% of all ICU patients in our institution. Perioperative care for aged patients has now become one of the most important clinical activities in the ICU. The perioperative management for those aged patients should be performed with great care because these patients have some abnormalities in water and electrolyte metabolism. Aged patients showed decreased blood levels of atrial natriuretic peptide (ANP) and decreased creatinine clearance even in the preoperative period. The ANP level and the creatinine clearance showed significant negative correlation, indicating that one of the reasons for impaired renal function among aged patients could be the decreased ANP level in blood. The intraoperative insults to the aged surgical patients undergoing radical operation for esophageal cancer tended to be smaller compared to that in the younger patients. Intraoperative infusion volume and urinary output were also smaller in the aged group compared to those in the younger group. The postoperative infusion therapy in the ICU mainly consisted of intravenous hyperalimentation with decreased Na content and the transfusion of fresh frozen plasma. This regimen should be more suitable for the aged patients. Even though the aged and the younger group received the same infusion therapy during their postoperative ICU stay up to the 7th day, the aged patients showed the tendency of Na and Cl retention and increase in anion gap. However, these abnormalities in water and electrolyte metabolism were not so severe as to cause clinical symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

[Evaluation of the effect of treatment in patients with liver tumors using 18F-fluorodeoxyglucose PET].

To evaluate the glucose metabolism in the liver tumor, 18FDG PET (Positron Emission Tomography) was performed in 9 patients with primary and metastatic liver tumors. And usefulness of 18FDG PET in clarifying the effect of treatment on liver tumor was examined. Glucose metabolism of tumor was showed in terms of the coefficient 'C' calculated by Patlak's plot. Each tumor's coefficient 'C' was 0.016-0.054 and it decreased after treatment. Compared with pathological findings, the coefficient 'C' of necrosis part of tumor was 0.004 and fibrous change after irradiation was 0.007. It suggested that coefficient 'C' reflected activity of tumor and it was a useful index to know viability of tumors in the treatment for patients with liver tumors.

Deoxy Sugars↗