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K Takai

Publications and source records attributed to K Takai.

At least 253 records · Page 14Linked to original sources
PubMed1984

Enzymatic dehydrogenation of tryptophan residues of human globins by tryptophan side chain oxidase II.

Enzymatic dehydrogenation of tryptophan residues in human alpha- and beta-globins has been demonstrated with tryptophan side chain oxidase II, a hemoprotein from Pseudomonas. In 1 M ammonium acetate, pH 4, the enzyme catalyzed the conversion of Trp-14 of alpha-globin to alpha, beta-dehydro-Trp. Under identical conditions, Trp-15 of beta-globin was converted to alpha, beta-dehydro-Trp, whereas Trp-37 was unmodified. No modification was obtained in 0.4% sodium dodecyl sulfate or 8 M urea. The dehydrogenase component of tryptophan side chain oxidase II was also active toward globins in the presence of ferricyanide, whereas tryptophan side chain oxidase I was inert. Upon analyses of the tryptic fragments of the modified beta-globin, two forms of alpha, beta-dehydro-Trp-15 distinguishable by ultraviolet absorption and fluorescence were identified. Each of them rapidly equilibrated with another form on irradiation at 300-380 nm. We tentatively assigned them to two isomers of alpha, beta-dehydro-Trp distinguishable by the configuration around its beta-carbon atom. alpha, beta-Dehydro-Trp in globins and certain polypeptides used herein showed a blue fluorescence at 420 nm. In [alpha, beta-dehydro-Trp 15]beta-globin, the fluorescence was exceptionally intense, the fluorescence yield being comparable to that of NADH. From several lines of evidence, the result was ascribed to the excitation energy transfer from Trp-37 to alpha, beta-dehydro-Trp-15 in the modified beta-globin.

Globins↗
PubMed1984

Food constituents as a cause of variation of C-peptide excretion in the urine.

Since C-peptide immunoreactivity (CPR) is excreted at a much higher rate than insulin in the urine, the urinary CPR (U-CPR) level could be a good measure of pancreatic B-cell function. In 10 normal subjects and 17 patients with non insulin-dependent diabetes mellitus (NIDDM), the 24-hour U-CPR level was 49.6 +/- 4.5 (mean +/- SE) micrograms, and 59.1 +/- 7.9 micrograms, respectively. When measured repeatedly during 4-37 consecutive days, the mean levels of coefficient of variation (c.v.) of 24-hour U-CPRs in each individual in normal and diabetic patients were 23.4 +/- 3.2%, and 39.1 +/- 1.2%, respectively. Thus, the daily fluctuation of U-CPR was considerably large not only in NIDDM but also in normal healthy subjects. In order to investigate factors responsible for these U-CPR variations, we analyzed the effect of food constituents on U-CPR excretion in this paper. In 8 healthy subjects 5-hour U-CPR excretions were measured after ingesting 5 kinds of isocaloric 300 kcal test meals, i.e. glucose, starch, protein, fat, and mixed meal which consisted of equal kcal of starch, protein and fat. Five hour U-CPR excretion after glucose, starch and protein meal ingestion was 9.5 +/- 1.3 micrograms, 13.7 +/- 1.9 micrograms, and 7.4 +/- 0.9 micrograms, respectively. Fat meal induced no increase in U-CPR excretion. After the mixed meal ingestion, 5-hour U-CPR was 8.2 +/- 0.6 micrograms, which was approximately the mathematical average for the U-CPR after 3 meals. We conclude that the cause of variations in the U-CPR excretion may be ascribed not only to the ingested total calories, but also to the nutritional components of the diet. Therefore, care must be taken in reading a daily U-CPR measurement in assessing pancreatic B cell function.

Adult↗
PubMed1984

[Computed tomography for the diagnosis of a renal mass].

The accuracy of differential diagnosis of renal mass lesions by computed tomography (CT) was evaluated. A retrospective study was done on 23 patients with renal mass lesion suspected by conventional IVP. Cases studied included 6 renal cell carcinomas, 1 nephroblastoma, 2 transitional cell carcinomas of renal pelvis, 3 parapelvic cysts, 2 polycystic kidneys and 9 other benign renal lesions. CT, especially with enhancement, is advantageous for evaluation of the extent of the tumor and also for the differentiation between cystic and solid masses by their attenuation. However, angiography and venography could provide valuable information for surgery of malignancy; and, retrograde pyelography also would help in assessing the extent of tumor spread in the renal pelvis. Two of our cases of parapelvic cyst and a case of renal bleeding could not be distinguished accurately by CT. Sonography or other diagnostic procedures might be helpful in such cases.

Adenocarcinoma↗
PubMed1984

[Cytotoxic activity of large granular lymphocytes (LGL) infiltrated into metastatic tumors of lung cancer].

Large granular lymphocytes (LGL) showing Leu 7 and weak E rosettes were separated from two metastatic tumors of lung cancer. Weak cytotoxic activity of these cells was recognized against autochthonous tumors, but never against K-562 cells. After OK-432 therapy, this cytotoxicity was not enhanced, but antibody dependent cell-mediated cytotoxicity (ADCC) of peripheral blood mononuclear cells of the patient was induced against metastatic tumors. These signs may suggest that specific immunotherapy should be available for these cancers.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1984

[Squamous cell carcinoma of the bladder--report of two cases].

Two cases of squamous cell carcinoma of the urinary bladder are presented. Initial pathologic diagnosis was based on biopsy findings; it was confirmed by findings on resected specimens. Since aggressive surgical therapy has been reported to be successful, we attempted radical surgery in both of our patients. A 76-year-old woman underwent total cystectomy with resection of segments of rectal and vaginal walls with ureterocutaneostomy and colostomy. The other patient, a 66-year-old woman was inoperable due to wide tumor invasion. She died two months later of cerebrovascular accident apparently unrelated to original disease. The ultrastructural findings, which typically show numerous tonofilaments, ribosomes and desmosomes, are presented and discussed.

Aged↗
PubMed1983

Picomole analyses of tryptophan by derivatization to 9-hydroxymethyl-beta-carboline.

A new method specific for the determination of subpicomole quantities of tryptophan has been developed by elaboration of the Pictet-Spengler reaction. It permitted reproducible quantitation of tryptophan in less than 1 microliter of plasma ultrafiltrate or 1 mg of brain tissue. Samples deproteinized by trichloroacetic acid were boiled for 15 min with formaldehyde and potassium ferricyanide at controlled acidity, where tryptophan was converted to a single new product identified as 9-hydroxymethyl-beta-carboline. It was quantitated by either direct spectrofluorometry or a reversed-phase HPLC system developed for beta-carbolines. Under our conditions, peptides containing N-terminal tryptophan such as Trp-Leu and delta sleep-inducing peptide gave N-(9-hydroxymethyl-beta-carboline-3-carbonyl) peptides which retained all amino acid residues except tryptophan.

Animals↗
PubMed1983

Prevalence of diabetic retinopathy and distribution of its severity among patients of a university clinic of diabetes in Osaka.

We have been following longitudinal changes of diabetic retinopathy by periodic fundoscopy in patients at our out-patient clinic for diabetes mellitus. In this study, we reviewed the prevalence of diabetic retinopathy and the distribution of its severities. Funduscopic examinations for retinopathy were performed on 242 patients. They ranged in age from 13 to 84 years (52.9 +/- 0.9, mean +/- s.e.). Duration of diabetes ranged from 1 to 31 years (10.7 +/- 0.4). Forty patients were treated with diet alone, 112 with oral hypoglycemic agents and 90 with insulin administration. No retinopathy was found in 83 patients (34%), background retinopathy in 113 (47%), preproliferative retinopathy in 24 (10%) and proliferative retinopathy in 17 (7%). Five patients (2%) were blind. Twenty-seven patients (60%) of 45 with a less than 5-year duration of diabetes were apparently without retinopathy, while the incidence of proliferative retinopathy increased in proportion to the duration. Fasting plasma glucose and glycosylated hemoglobin levels were higher in the patients with proliferative retinopathy than in any other group. All of the blind patients had a long history of untreated diabetes. Whether diabetic control assessed by glycosylated hemoglobin influences the progression of retinopathy could not be demonstrated by a 2-year observation. Further analysis based on a longer duration is needed in this respect.

Adolescent↗
PubMed1983

[Synchronous double cancer of the esophagus and the urinary bladder: report of two cases].

An 82-year-old man was seen with the complaints of gross hematuria and dysphagia in September 1979. An invasive bladder tumor was found and TUR-Bt (Transitional cell carcinoma, G2, pT3NXMO ) was performed. Fluoroscopic examination revealed a large esophageal cancer (Undifferentiated squamous cell carcinoma, T2NXMO ) and irradiation was performed (Linac 4,600 rads). The patient's condition aggravated rapidly and he died in February 1980. A 76-year-old man irradiated for an esophageal cancer (Linac 6,540 rads) (undifferentiated squamous cell carcinoma, T1NXMO ) in March 1981. Eleven months later, bladder cancer was found and treated with TUR-Bt (Transitional cell carcinoma, G2, PTlmNXMO ) followed by intravesical instillation of carboquone and adriamycin. The patient was alive 1 year and 9 months after the diagnosis of the esophageal cancer. Sixteen cases of double cancer of the esophagus and urinary bladder were found in the Japanese literature. Eighteen cases including the above 2 cases were males and their ages ranged from 51 to 82 years. Sixteen bladder cancers were transitional cell carcinoma and 15 esophagus cancers were squamous cell carcinoma. Of 9 cases whose clinical course were described in detail, 3 were synchronous and 6 were metachronous. Radical surgery was performed for one or both of the two cancers in 5 cases, 4 of which were metachronous. Indication of surgery for the metachronous second cancer does not differ significantly from sporadic cancer when the first cancer has been managed successfully. However, the treatment for the synchronous double cancer of this type of combination is often forced to be restricted, since the prognosis of esophageal cancer is poor and surgical risk may be increased by two radical surgeries in such elderly patients.

Aged↗
PubMed1982

[Substance P].

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Animals↗