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Biomedical subjects

T Seki

Publications and source records attributed to T Seki.

At least 631 records · Page 35Linked to original sources
PubMed1984

Anaesthetic management with morphine in phaeochromocytoma.

Morphine was used as the principal anaesthetic agent for five patients undergoing resection of phaeochromocytoma, and changes in plasma catecholamines were monitored. Phenoxygenzamine (0.5 mg X kg-1 X day-1) was orally given one week before operation. After premedication with hyoscine (0.4 mg) and diazepam (20 mg) of meperidine (50 mg), anaesthesia was induced with an infusion of morphine (1 mg X kg-1) over 30 min and maintained with diazepam, nitrous oxide and oxygen. Pancuronium was used as the muscle relaxant. In three of the five patients, blood pressure transiently rose (ranging from 15 to 60 mg) following orotracheal intubation, but vasodilators were not required. In two of the three, plasma norepinephrine increases were 1.1 and 1.3 ng X ml-1. In the other two patients, whose blood pressure was stable, the change in plasma norepinephrine was 0.1 and 0.7 ng X ml-1. After reaching a peak at the time of ligation of drainage vein from the tumour, plasma catecholamines rapidly decreased to the preoperative levels, but the blood pressure was well maintained in all cases. Ventricular arrhythmias did not occur despite the increased levels of endogenous catecholamines. These findings suggest that morphine can be used as an alternative anaesthetic agent during operation for phaeochromocytoma and that exaggerated pressor responses to morphine (when given slowly) seem not to occur in phaeochromocytoma.

Adrenal Gland Neoplasms↗
PubMed1984

A fluorometric determination of urinary 17-hydroxycorticosteroids using benzamidine.

A fluorometric determination of urinary 17-hydroxycorticosteroids using a reaction of benzamidine with compounds carrying the dihydroxyacetone side chain is described. The fluorescent compounds have excitation and emission maxima at 370 and 480 nm, respectively. The method includes enzymatic hydrolysis with beta-glucuronidase (EC 3.2.1.31, from Escherichia coli) and extraction with methylene chloride and generation of fluorescence in alkaline solution (pH 13.4). The specificity of the reaction was examined and the results were compared with those of an accepted method based on the Porter-Silber reaction (C. C. Porter and R. H. Silber, 1950, J. Biol. Chem. 185, 201-207). The coefficient of correlation was 0.945 with regression line of y = 0.91x + 0.7 mg/day (y, present method; x, Porter-Silber reaction method). Sensitivity of the reaction was 0.5 microgram/ml of standard or sample, mean recovery of cortisol added to five urine samples (5-micrograms addition) was 95%, and the coefficient of variation of the method (five repeated assays of sample with a value of 5.2 mg/liter) was 6.2%.

17-Hydroxycorticosteroids↗
PubMed1984

Amosulalol, a combined alpha and beta adrenoceptor antagonist: kinetics after intravenous and oral doses.

Amosulalol kinetic studies were conducted in seven subjects who received 0.16 mg/kg iv and in 18 subjects who received 12.5, 25, 50, 100, or 150 mg by mouth. Plasma levels of amosulalol after intravenous dosing declined biphasically and fitted a two-compartment model. Kinetics were as follows: coefficients A = 0.85 +/- 0.09 microgram/ml and B = 0.22 +/- 0.01 microgram/ml; rate constants alpha = 2.78 +/- 0.24 hr-1 and beta = 0.25 +/- 0.01 hr-1; elimination rate constants, k12 = 1.36 +/- 0.17 hr-1, k21 = 0.78 +/- 0.06 hr-1, and kel = 0.88 +/- 0.06 hr-1; terminal phase volume of distribution = 0.75 +/- 0.06 l/kg; clearance = 8.09 +/- 0.54 l/hr; AUC = 1.22 +/- 0.09 microgram . hr/ml; and t1/2 alpha = 0.26 +/- 0.02 hr and t1/2 beta = 2.8 +/- 0.1 hr. After single oral doses, amosulalol peak plasma levels were generally reached within 2 to 4 hr. Maximum plasma concentrations and AUC increased in a dose-dependent manner, whereas t1/2 were about 5 hr (range 4.4 to 5.7 hr) at each dose. Systemic availability of amosulalol was about 100% as determined by the ratio of AUC after oral and intravenous dosing. These results suggest that amosulalol is well absorbed and is little affected by first-pass metabolism.

Administration, Oral↗
PubMed1984

Expression of the Thy-1 glycoprotein gene by DNA-mediated gene transfer.

We isolated a gene encoding the Thy-1.2 glycoprotein from a recombinant library constructed from BALB/c mouse DNA. To evaluate the expression of this cloned gene in different genomic environments, we introduced it into cell lines derived from fibroblast, lymphoid, and neuronal tissues by DNA-mediated gene transfer. When integrated into the genome of mouse L cells, cell-surface Thy-1 can be detected with anti-Thy-1 monoclonal antibodies. These L-cell lines contain between two and four copies of the cloned Thy-1 gene stably integrated in the host genome. After subcloning into a plasmid vector containing the bacterial Eco-gpt gene as a selectable marker, the Thy-1 gene was introduced into the Thy-1-deficient mouse lymphoma AKR1 (Thy-1-d), and the rat neuronal cell line, B50. The resulting transformants also contain two to four copies of the cloned Thy-1 gene but express up to 50-fold more cell-surface Thy-1.2 than the L cell transformants. The expression of vastly differing amounts of cell-surface Thy-1 from similar numbers of genes suggests that the gene encoding this differentiation antigen is under tissue-specific regulation.

Animals↗
PubMed1984

Metaretinochrome in membranes as an effective donor of 11-cis retinal for the synthesis of squid rhodopsin.

Aporetinochrome, which is a protein moiety of retinochrome without chromophore retinal, is found in the membrane containing retinochrome. All of the prosthetic retinal of retinochrome in membranes, which is all-trans retinal, is bound to the chromophoric site on the protein moiety, with protonated Schiff bases showing an absorption band with the maximum at 495 nm. On exposure to light, retinochrome is converted to metaretinochrome at room temperature. The prosthetic retinals of metaretinochrome in membranes, which are 11-cis retinals, are in two states: retinals bound to the chromophoric site with protonated Schiff bases, and the free retinals, which are separated from the protein moiety. These states are suggested from the following observations. (a) The ratio of the absorbance at 470 nm of metaretinochrome to that at 495 nm of the parental retinochrome differs because of differences in samples and is higher in the purer preparations. (b) The difference spectrum of absorption of metaretinochrome caused by alkalinization shows two minimum peaks at approximately 420 and 470 nm. (c) The rate of bleaching of metaretinochrome in membranes with dilute NH2OH is much faster than that of retinochrome, and the absorption band in the near-UV region is more susceptible to NH2OH than the visible absorption band. The state of the prosthetic retinals in metaretinochrome was confirmed directly by the reaction of metaretinochrome in membranes with NaBH4. After treatment with NaBH4, the sodium dodecyl sulfate-polyacrylamide gel electrophoretic pattern shows two fluorescent bands: one at the position that corresponds to the retinochrome protein (mol wt 27,000 +/- 2,000), and another at the front of migration, where no band of protein is observed. Retinoids extracted from the NaBH4-treated metaretinochrome in membranes and analyzed with high-pressure liquid chromatography show a main peak of 11-cis retinol. The results of this and earlier (Seki et al., 1982) papers are summarized, and it is strongly suggested that metaretinochrome in the squid retina may play the role of 11-cis retinal donor for opsin and contribute to the synthesis of the squid rhodopsin.

Absorption↗
PubMed1984

Construction of a promoter-probe vector for a Bacillus subtilis host by using the trpD+ gene of Bacillus amyloliquefaciens.

The trp gene cluster of Bacillus amyloliquefaciens was found to be structurally similar to that of the Enterobacteriaceae. The translation termination codon of the putative trpE gene and the initiation codon for the putative trpD gene overlap at the trpE-trpD junction, and a promoter for the putative trpC gene is suggested to exist. A promoter-probe vector of Bacillus subtilis, pFTB281, was constructed with a DNA fragment of B. amyloliquefaciens, complementing the trpC and trpD mutations of B. subtilis, a 42-base-pair DNA fragment of M13mp7, and the larger EcoRI-PvuII fragment of pUB110, which confers an autonomous replication function and the kanamycin-resistance phenotype to the chimeric plasmid. pFTB281 has BamHI, EcoRI, and SalI cloning sites in the 5'-upstream portion of the protein-coding region of the putative trpD gene, and the insertion of a certain DNA fragment at any of these sites allowed the plasmid to transform a trpD mutant of B. subtilis to the TrpD+ phenotype. DNA fragments showing the promoter function for the trpD gene were obtained from B. amyloliquefaciens and Saccharomyces cerevisiae chromosomes and rho 11 and lambda phage DNAs, but rarely from the DNAs of Escherichia coli and pBR322.

Amino Acid Sequence↗
PubMed1984

Identification of source of excessive ACTH production by improved selective venous sampling: simultaneous assay of PRL as a pituitary marker.

To identify an obscure site of excessive ACTH production, selective venous sampling was performed by Seldinger's method in a 32-year-old man. Differential diagnosis between an ectopic ACTH producing tumor and Nelson's syndrome was quite inconclusive in this patient in spite of extensive clinical and laboratory evaluations, including pituitary surgery. In this study, PRL was measured in every sample as a reliable marker for pituitary drainage. Significantly higher rations (2.6 to 5.3) of catheter to peripheral (C/P) concentration of PRL at sites closer to the pituitary indicated successful samplings of pituitary drainage. C/P ratios of ACTH correlated very closely (correlation coefficient = 0.906, p less than 0.01) with those of PRL at every sampling site. Thus, it was concluded that the site of excessive ACTH production in this patient was in the pituitary gland. The methods applied in this study appear to be useful in differentiating ectopic from eutopic production of other pituitary hormones as well.

Adolescent↗
PubMed1984

Malignant potential of homozygous and heterozygous complete moles.

There are two main mechanisms of origin for complete hydatidiform mole: (a) fertilization of an empty egg by a haploid sperm followed by duplication (monospermic mole); and (b) fertilization of such an egg by two haploid spermatozoa (dispermic mole). The former is inevitably homozygous (homozygous mole), whereas the latter may be heterozygous for a given genetic marker (heterozygous mole). A recent cytogenetic study showed that three cases of choriocarcinoma were undoubtedly heterozygous, which prompted us to compare the incidence of postmolar sequelae between patients with homozygous moles and those with heterozygous moles. Making use of chromosomal heteromorphisms and human lymphocyte antigen and phosphoglucuromutase 1 polymorphisms, we established the androgenetic origin of a complete mole in 49 of 56 cases. Homozygosity was confirmed in 21 moles, and heterozygosity was confirmed in five. Three of five patients with heterozygous moles developed postmolar trophoblastic disease, whereas none of the 21 patients with homozygous moles suffered postmolar trophoblastic disease except one who showed signs of degenerating residual trophoblasts. Consistent with this observation is the fact that all of the four destructive moles studied here were of dispermic origin. Thus, heterozygous moles seem to have a higher malignant potential than do homozygous moles.

Chromosome Aberrations↗
PubMed1984

[Urinary excretion of N-acetyl-beta-D-glucosaminidase in patients with urological disease: with special reference to hydronephrosis].

Activity of urinary N-acetyl-beta-D-glucosaminidase (NAG) has been studied in patients with urological diseases. In most patients with benign prostatic hyperplasia, prostate cancer and bladder cancer, activity of urinary NAG was elevated (92.9%), especially in cases of indwelling catheterization or poor visualization of IVU. Urinary NAGs were also elevated for all patients with renal stones, ureter stones, uretero-cutaneous stomy or a single kidney. In hydronephrosis or hydronephrosis with hydroureter patients, urinary NAG level was low pre-operatively, but increased post-operatively. Urinary beta 2-microglobulin (BMG) showed a similar tendency in patients with hydronephrosis or hydronephrosis with hydroureter. Electronmicroscopic observations of the kidney in such patients revealed many primary and secondary lysosomes.

Acetylglucosaminidase↗
PubMed1983

Simple enzymatic detection method for urinary sulfated 7 alpha-hydroxy bile acids in normal subjects and in patients with acute hepatitis.

Urinary sulfated primary bile acids, 7 alpha-hydroxy bile acids, are detected by an enzymatic method using 7 alpha-hydroxysteroid dehydrogenase (EC 1.1.1.-, 7 alpha-HSD) after chromatographic fractionation on Sephadex G-25. Urinary sulfated or glucuronated bile acids are hydrolyzed by beta-glucuronidase/sulfatase (EC 3.2.1.31/EC 3.1.6.1) from Helix pomatia and then released 7 alpha-hydroxy bile acids are detected with 7 alpha-HSD in the presence of beta-ND+, diaphorase (EC 1.6.99.2, from Clostridium kluyveri) and 2-p-iodophenyl-3-p-nitrophenyl-5-phenyltetrazolium chloride. The absorbance of formazan formed during the enzymic reaction is measured at 500 nm. Excretion values of 7 alpha-hydroxy bile acids in normal subjects and in patients with acute hepatitis were compared. This enzymatic detection method for the excretion pattern of urinary 7 alpha-hydroxy bile acids may be useful for clinical diagnosis.

Bile Acids and Salts↗
PubMed1983

Distribution of immunoreactive thyrotropin-releasing hormone in the forebrain and hypophysis of the bullfrog, Rana catesbeiana.

The distribution of immunoreactive thyrotropin-releasing hormone (TRH) in the forebrain and hypophysis of Rana catesbeiana was studied by means of specific radioimmunoassay and immunohistochemistry based on peroxidase-antiperoxidase (PAP) techniques. A relatively high concentration of immunoassayable TRH is present in the hypothalamus. Immunoreactive TRH cell bodies are found in the anterior part of the preoptic nucleus, the dorsal infundibular nucleus, the nucleus of diagonal band of Broca, and the medial part of the amygdala. Immunoreactive nerve terminals are observed in the neurohypophysis and the external layer of the median eminence, where the terminals are in close contact with the capillary loops of the hypophyseal portal vessels. The possible role of TRH in the frog brain is discussed.

Animals↗
PubMed1983

Antigenic structure of adenylate kinase from porcine skeletal muscle--II. Immunochemical cross-reactivity of fragments from adenylate kinase.

Specific antibody to a fragment [CBb(2-56)] of porcine muscle adenylate kinase was purified from goat antiserum against adenylate kinase on an immunoadsorbent column. This anti-CBb antibody cross-reacted in solid phase radioimmunoassay with two other CNBr-fragments of adenylate kinase, CBfN(81-125) and CBfC(126-194). This cross-reactivity explained their high inhibition activities in quantitative precipitin reaction between adenylate kinase and goat antiserum shown in the previous work. Cysteinyl residues of the enzyme (positions 25 and 187) were S-cyanylated with 2-nitro-5-thiocyanobenzoic acid and the enzyme was cleaved at these residues. Fragment 1-24 thus obtained was purified. The fragment 1-24, composing the N-terminal half of CBb(2-56), accounted for full activity of CBb to anti-CBb in radioimmunoassay. Hence antigenic region(s) of CBb(2-56) exist in its N-terminal half, 2-24, and this determinant(s) may be closely related to the cross-reactivity among CB-fragments. CBfN also bound to the antibody fraction which had not been adsorbed to CBb-Sepharose (non-anti-CBb). CBfN carried additional antigenic regions. In conclusion, we propose that the antigenic reactive region(s) of adenylate kinase responsible for the cross-reactivity of the CB-fragments are as follows: -Glu-Glu-Lys-Leu-Lys-Lys- (2-7), -Glu-Glu-Phe-Lys-Arg-Lys- (103-108), -Glu-Glu-Thr-Ile-Lys-Lys- (143-148).

Adenylate Kinase↗
PubMed1983

Construction of a Bacillus subtilis cloning vehicle with heterologous DNA sequence.

A cloning vehicle, pFTB91, for the Bacillus subtilis host was constructed with DNA fragments heterologous to the host chromosome. It consists of three DNA fragments: (i) chromosomal DNA of Bacillus amyloliquefaciens which complements the leuA and ilvC mutations in B. subtilis; (ii) a B. amyloliquefaciens plasmid DNA that supplies an autonomously replicating function; and (iii) a HindIII fragment of Staphylococcus aureus plasmid pTP5 that carries gene tetr, conferring the TetR phenotype. It has sufficiently low DNA homology to prevent its integration into the host chromosome in recombination-competent cells of B. subtilis. It is 9.3 kb, and approx. 10 copies are present per chromosome. The SalI and KpnI sites in the ilvC+ and tetr genes, respectively, could be used for selection of recombinant plasmids by insertional inactivation. The plasmid has unique sites for EcoRI, PstI, and XbaI.

Bacillus↗