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Biomedical subjects

T Kodama

Publications and source records attributed to T Kodama.

At least 775 records · Page 43Linked to original sources
PubMed1987

Major intrinsic polypeptide (MIP26K) of the lens membrane: covalent change in an internal sequence during human senile cataractogenesis.

Polyclonal antisera to three synthetic peptides of bovine MIP26K have been used in combination with Western blot analysis to probe for changes of the MIP26K molecule during human senile cataractogenesis. Anti-MIP26K229-237 binds well to the 26K component from cataractous lens membranes, but binds poorly to the same component from normal lens. In contrast, antisera to two other sequences of MIP26K (anti-MIP26K252-259 and anti-MIP26K256-263) bind approximately equally well to the 26K component from either cataractous or normal lens. Together, these results demonstrate that during cataract development there is a selective covalent change in a region of the MIP26K molecule that may have profound effects upon the ability of this molecule to facilitate intercellular communication between lens fiber cells.

Amino Acid Sequence↗
PubMed1987

Cloning and regulation of rat apolipoprotein B mRNA.

Recombinant cDNA clones that code for apolipoprotein B(apoB) were isolated from a rat liver cDNA library, using synthetic oligonucleotide probe derived from the sequence of human apoB cDNA. The nucleotide and deduced amino acid sequences of the rat apoB clone pRB5, 1.2 kb in length, showed 83% and 84% homology to those of human apoB. Northern blot analysis revealed that rat apoB cDNA probe cross-reacts with human and rabbit apoB mRNA sequences and the size of those mRNAs, approximately 15 kb long, were not discernibly different. In addition, apoB mRNA was abundant only in the liver and intestine. Finally, cholesterol feeding to rats for six weeks resulted in a several-fold increase in the level of apoB mRNA in the liver.

Animals↗
PubMed1987

Acoustic schwannoma presenting as subarachnoid hemorrhage due to ruptured contact aneurysm.

The authors report a rare combination of aneurysm and acoustic schwannoma in a 66-year-old housewife, who developed subarachnoid hemorrhage from a ruptured aneurysm arising from an arterial branch of the posterior inferior cerebellar artery on the tumor capsule. Association of aneurysm and cerebellopontine angle schwannoma is extremely rare, and there has been no report of subarachnoid hemorrhage due to ruptured contact aneurysm, although previous reports indicated a small number of acoustic schwannomas accompanying hematomas in and around tumors.

Aged↗
PubMed1987

Infection of feline lymphoid cells with feline leukemia virus in culture.

An in-vitro system for infection of cat T lymphocytes with feline leukemia virus (FeLV) was developed. For establishment of this system, FeLV was inoculated in vitro into concanavalin-A stimulated primary lymphoid cells and long-term cultured T cells grown with interleukin-2 (IL-2) from various feline lympho-hematopoietic organs. During serial cultivation with IL-2, FeLV group-specific antigen (GSA) was detected 5-6 weeks after infection in the primary cultures, and 1 week after infection in the long-term cultures of T cells. The percentage of FeLV-GSA-positive cells gradually increased with passages and reached more than 80% in several cultures of lymphoid cells, that became persistently infected and produced FeLV. These FeLV-infected lymphoid cells expressed T-cell markers, but showed no obvious differences in growth or cytological characteristics from FeLV-free feline lymphoid cells during the observation period of 60 weeks.

Animals↗
PubMed1987

Covalent changes at the N- and C-terminal regions of gamma crystallin during aging of the normal human lens.

Polyclonal antisera have been made to synthetic peptides corresponding to the N- and C-terminal regions of the putative gamma 1-2 gene from human lens. These antisera are specific for gamma crystallin, showing no cross-reactivity with any polypeptides of the alpha- and beta-crystallin fractions. Western blot analysis demonstrates a dramatic decrease in the binding of these antisera to gamma crystallin during aging of the normal human lens, while identical analysis with polyclonal antisera to the major cyanogen bromide fragment (19,000 MW) of human gamma crystallin shows little, if any, change during aging. Together, these demonstrate that antisera to synthetic peptides of the N- and C-terminal regions of the gamma 1-2 gene are very specific probes that can demonstrate extensive covalent modification from both ends of the gamma crystallin molecule during aging of the normal human lens.

Adolescent↗
PubMed1987

Serum bile acid profile in thyroid dysfunction and effect of medical treatment.

1. Serum non-esterified bile acid profile was examined in patients with thyroid dysfunction. Sixteen hyperthyroid patients, six hypothyroid patients, nine patients taking thyroid or antithyroid drugs and 26 healthy controls were studied. The medicated patients were euthyroid when serum samples were collected. Bile acid concentration was determined by the simplified microassay method involving mass fragmentation spectrometry. 2. The sum of the concentrations of the individual bile acids was not significantly different among the four groups. However, the composition of bile acid reflected the thyroid function. The most prominent bile acid was deoxycholic acid in the hypothyroid patients and chenodeoxycholic acid in the hyperthyroid patients. The serum bile acid profile of medically treated patients was similar to that of normal controls. The ratio of the sum of deoxycholic and cholic acid to that of lithocholic and chenodeoxycholic acid was found to be a good indicator of thyroid function, while the ratio of cholic acid to chenodeoxycholic acid correlated poorly with it. 3. The characteristic effect of thyroid hormone on the serum bile acid composition in man was the shift from the 'family' of cholic acid to that of chenodeoxycholic acid. This is in agreement with experimental results in the rat, and suggests a specific action of thyroid hormone on the hydroxylating enzymes involved in the conversion of cholesterol into bile acids.

Adolescent↗
PubMed1987

Hormonal status of gastric cancer. I. Effect of rice and salty rice diets on the constitution of urinary steroids in mice.

We investigated the effect of rice and salty rice diets on the physical growth and on the constitution of urinary steroids in Swiss/ICR mice. The following three kinds of diets were employed in the feeding experiment: 1) standard diet; 2) rice diet; and 3) salty rice diet. Long-term maintenance of mice on both rice and salty rice diets led to a relative increase of tetrahydrocortisol associated with a concomitant decrease of androgen, progestin, and cholesterol in urine. Evidence was presented to indicate that the activity of endogenous hydrocortisone in mice could be augmented by an increased intake of sodium chloride alone; there was also evidence that the glandular stomach of a young mouse drinking physiological saline is highly sensitive to a suppressive action of hydrocortisone. We concluded that the two experimental diets produced a state of catabolic glucocorticoid excess combined with a deficiency of anabolic androgen and progestin. Mineralocorticoid status was not examined. In the salty rice diet, a markedly lower weight gain was observed, whereas in the rice diet, in general, no significant weight changes were observed.

Animals↗
PubMed1987

Hormonal status of gastric cancer. II. Abnormal constitution of urinary steroids in gastric cancer patients.

We undertook a case-control study regarding the excretions of 14 urinary steroids in gastric cancer (GC) patients. The results are as follows: the levels of androgens, progestins, and two corticosteroids were, relative to tetrahydrocortisol, significantly depressed in GC patients of both sexes compared with the corresponding normal controls. The deviation profile of urinary steroids was not affected by radical gastrectomy. Evidence indicated that observed changes of GC urines were the steroidal expression of a decrease of endogenous testosterone combined with an increase of endogenous hydrocortisone; there was also evidence that the hormonal environment of our GC patients was endocrinologically homologous to that of rice-fed or salty rice-fed mice. Epidemiological inquiry revealed that GC patients having more access to rice-rich or salt-rich diets were taller and less obese than were rural healthy controls. In agreement with the anthropometric data of those cancer patients is the finding that the specific death rate of GC (as calculated for each of 15 prefectures of northern Japan) was positively correlated for each sex with the mean heights, but not with the mean weights, of 14-year-old youths of those areas. This paper discusses the possible relevancy of the hormonal and epidemiological aspects of GC patients to gastrocarcinogenesis in light of steroid physiology.

Adult↗
PubMed1987

Resistance of human bronchial epithelial cells to teleocidin in a two-stage carcinogenesis experiment.

The tumor-promoting activity of teleocidin in two-stage carcinogenesis was tested using human bronchi grafted into athymic nude mice. On treatment with 7,12-dimethylbenz(a) anthracene (DMBA) plus teleocidin, no bronchial carcinomas were produced in 44 grafted human bronchi, but 8 spindle cell sarcomas developed in mouse tissues. Application of DMBA to grafted human bronchi produced only 3 spindle cell sarcomas in the tissues of 30 mice. Application of teleocidin did not produce any tumors in 24 grafts of bronchi obtained from heavy smokers. Thus, teleocidin had an effect on mouse tissues, but seemed to have no effect on human bronchial cells, although it is uncertain whether the grafted human bronchi were initiated by DMBA.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1987

Effects of oxygen on glucose-limited growth of Streptococcus mutans.

Aerotolerance in the growth of Streptococcus mutans and related streptococci was examined under glucose-limited conditions. The growth rate of all strains tested was more or less retarded when they were transferred from anaerobic to aerobic conditions. As for growth yield, however, some strains (group 1) showed reduced values for the increment of cellular dry weight change (in grams per mole of glucose), whereas others showed either unaltered (group 2) or increased (group 3) yields. The characteristic feature of strains in groups 2 and 3 was their high activity of both glucose- and pyruvate-dependent oxygen uptake when strains were grown under aerobic conditions. By contrast, the activity of pyruvate-dependent oxygen uptake by group 1 strains was negligibly low, whether grown under aerobic or anaerobic conditions. Some strains (group 1a) consumed oxygen in the presence of glucose at a much faster rate than others did (group 1b). There seems to be a good correspondence of these aerotolerance groupings to those based on serotypes of S. mutans. Thus, the groups 1a, 1b, 2, and 3 correspond to serotypes g, a+d, c+f, and b, respectively.

Aerobiosis↗
PubMed1987

2-Methylthio-1,4-naphthoquinone, a unique sulfur-containing quinone from a thermophilic hydrogen-oxidizing bacterium, Hydrogenobacter thermophilus.

A quinone was extracted and purified from the cells of an extremely thermophilic hydrogen bacterium, Hydrogenobacter thermophilus TK-6 (IAM 12695). Its chemical structure was determined as 2-methylthio-3-VI, VII-tetrahydromultiprenyl-1,4-naphthoquinone by elemental analysis, 1H nuclear magnetic resonance spectroscopy, mass spectroscopy, and infrared spectroscopy of the quinone and by gas-liquid chromatography and gas chromatography-mass spectroscopy analysis of the ozonolysis products of the quinone. It was shown that the other five strains of H. thermophilus have the same quinone system. We named the quinone with the 2-methylthio-1,4-naphthoquinone nucleus "methionaquinone." The abbreviation of MTK is recommended for this class of quinone.

Bacteria↗
PubMed1987

Purification and properties of haloalkane dehalogenase from Corynebacterium sp. strain m15-3.

A haloalkane dehalogenase was purified to electrophoretic homogeneity from cell extracts of a 1-chlorobutane-utilizing strain, m15-3, which was identified as a Corynebacterium sp. The enzyme hydrolyzed C2 to C12 mono- and dihalogenated alkanes, some haloalcohols, and haloacids. The Km value of the enzyme for 1-chlorobutane was 0.18 mM. Its molecular weight was estimated to be 36,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 33,000 by gel filtration. The isoelectric point was pH 4.5. The optimum pH for enzyme activity was found to be 9.4, and the optimum temperature was 30 to 35 degrees C. The enzyme was stable for 1 h at temperatures ranging from 4 to 30 degrees C but was progressively less stable at 40 and 50 degrees C.

Amino Acids↗
PubMed1987

Acute suppurative thyroiditis in appearance of unusual neck mass.

We report on three adult cases of acute suppurative thyroiditis due to infection through a piriform sinus fistula. In these cases, the lesion did not exhibit the clinical symptoms characteristic of acute suppuration, but appeared as an unusual neck mass. Repeated barium meal roentgenograms, however, demonstrated the internal fistula in two of the three cases. Acute suppurative thyroiditis may not be so rare even in adults. When acute suppurative thyroiditis occurs in adults with scanty symptoms of acute suppuration, the piriform sinus fistula could easily go undetected. Recognition of acute suppurative thyroiditis in adults per se seems to be important for correct diagnosis.

Acute Disease↗
PubMed1987

Eleven cases of nonfunctioning parathyroid cyst--significance of needle aspiration in diagnosis and management.

Eleven cases of nonfunctioning parathyroid cyst are reported. Ultrasonography revealed the cystic nature of the asymptomatic lump in the neck. Clear watery fluid obtained by needle aspiration and the increased parathyroid hormone concentration in the fluid established the diagnosis. Five patients, in four of whom the cysts reappeared after one (3 cases) or seven (1 case) needle aspirations, underwent surgical resection of the cysts. Six other patients were followed conservatively after the aspiration maneuver. In four patients with enough follow-up time for evaluation, the cyst fluid has not reaccumulated 5, 2 and 2 years after only one aspiration, and 1 year after two aspirations. In one patient, the cyst reappeared 9 months after the initial aspiration. Simple percutaneous aspiration may be curative in some cases of nonfunctioning parathyroid cysts.

Adult↗