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Biomedical subjects

J Goto

Publications and source records attributed to J Goto.

At least 181 records · Page 10Linked to original sources
PubMed1988

Immunohistochemical studies of ameloblastoma with special emphasis on keratin.

Ten cases of ameloblastoma including a case of gingival origin and a case of atypical ameloblastoma were studied immunohistochemically, especially with monoclonal and polyclonal anti-keratin antibodies. Stellate reticulum cells reacted strongly with monoclonal and polyclonal anti-keratin antibodies but columnar cells were reacted weakly. The level of keratinization of columnar cells was similar to that of the basal cell layer of the gingival squamous epithelium. Our immunohistochemical studies suggested that the process of keratinization-ameloblastoma follows the sequence of 1) cuboidal cells 2) columnar cells 3) stellate reticulum cells and 4) metaplastic squamous cells. The findings also disclosed the epithelial nature of granular cells. The reactivity of the components of atypical ameloblastoma differed from that of other cases. Other positive "markers" in ameloblastomas included CEA and CA19-9, but no particular histologic differences were observed between positive and negative cases.

Adult↗
PubMed1988

A facile one-step synthesis of delta 1,4-3-keto bile acid esters by iodoxybenzene and benzeneselenic anhydride.

A facile one-step conversion of stereoisomeric methyl 3-hydroxycholanoates to 1,4-dien-3-one, by treatment in boiling toluene with iodoxybenzene catalyzed by benzeneselenic anhydride, is described. The direct oxidation-dehydrogenation at C-3 is applicable to other cholanoates (hyodeoxycholic, chenodeoxycholic, ursodeoxycholic, deoxycholic, and cholic) when the hydroxyl groups at C-6, C-7, or C-12 are protected. Without protection at C-6 and C-7, the products from hyodeoxycholic, chenodeoxycholic, ursodeoxycholic, and cholic esters are complex mixtures, whereas, methyl deoxycholate yields the 1,4-dien-3,12-dione cleanly.

Benzene Derivatives↗
PubMed1988

Potential bile acid metabolites. 13. Improved routes to 3 beta, 6 beta- and 3 beta, 6 alpha-dihydroxy-5 beta-cholanoic acids.

New synthetic routes to three possible stereoisomers of hyodeoxycholic (3 alpha, 6 alpha-dihydroxy-5 beta-cholanic) acid are described. The principal reactions involved were inversion at C-3 of 3 alpha-hydroxy-6-oxo derivatives with diethyl azodicarboxylate-triphenylphosphine-formic acid and with N,N-dimethylformamide, without allomerization to the more stable 5 alpha form. On the basis of physical and chromatographic data, previously reported 3 beta, 6 alpha-dihydroxy-5 beta-cholanic acid and its methyl ester are shown to be C-3 epimeric mixtures. The 13C nuclear magnetic resonance spectra were of key importance in characterizing the stereoisomers and estimating their purity.

Chemical Phenomena↗
PubMed1987

Studies on steroids. CCXXVII. Separation and determination of bile acid 7- and 12-sulphates in urine by high-performance liquid chromatography with fluorescence labelling.

A method for the characterization and determination of bile acid 7- and 12-sulphates in urine without prior deconjugation is described. The sulphate fraction was obtained from an urine specimen by passing it through a Sep-Pak C18 cartridge, followed by group separation by ion-exchange chromatography on a lipophilic gel, piperidinohydroxypropyl Sephadex LH-20. Bile acid 7- and 12-sulphates were derivatized quantitatively into the fluorescent compounds through the hydroxyl group at C-3 by treatment with 1-anthroyl nitrile in the presence of quinuclidine in acetonitrile. Subsequent resolution into individual 7- and 12-sulphates was attained by high-performance liquid chromatography (HPLC) on a Cosmosil 5C18 column using 0.3% potassium phosphate buffer (pH 4.0)-methanol (1:3) as a mobile phase. The 3-(1-anthroyl) derivatives of 7- and 12-sulphates were monitored by fluorescence detection. Taurochenodeoxycholate 7-sulphate in human urine was unequivocally identified on the basis of behaviour in HPLC using mobile phases of different pH values. The present method has proved to be applicable to the characterization and quantification of bile acid 7- and 12-sulphates in human urine.

Bile Acids and Salts↗
PubMed1987

Capillary gas chromatography of hydroxylated bile acid stereoisomers of the allo and normal series.

Relative retention times and methylene unit (MU) values were determined for 56 bile acids of the allo (5 alpha, A/B-trans) and normal (5 beta, A/B-cis) series, which differ from one another in the number, position and configuration of the hydroxyl groups at positions C-3, C-6, C-7 and/or C-12. The bile acids were derivatized to their methyl ester O-trimethylsilyl ethers (Me-TMS) and methyl ester O-dimethylethylsilyl ethers (Me-DMES), and chromatographed on fused-silica capillary columns, chemically bonded with non-selective OV-1 and selective PEG-20M liquid phases. Of the four possible combinations of derivatives and columns examined, Me-DMES on OV-1 and Me-TMS on PEG-20M were most suitable. The differences in the MU values between the 5 alpha- and 5 beta-series, and between the Me-DMES and Me-TMS ether derivatives, are also summarized. These retention data would be helpful in the identification of closely related bile acid stereoisomers or for estimation of their structures. photolysis.

Bile Acids and Salts↗
PubMed1987

Studies on steroids. CCXXVIII Trace analysis of bile acids by gas chromatography-mass spectrometry with negative ion chemical ionization detection.

A suitable derivatization method for the trace analysis of bile acids by gas chromatography (GC) in combination with negative ion chemical ionization (NICI) mass spectrometry is described. Of various derivatives for the carboxyl group, the pentafluorobenzyl (PFB) ester provided the highest value of the ratio of the negative to the positive ion current. A characteristic carboxylate anion [M - 181]- was produced as the most abundant ion by the loss of the PFB group in NICI. The PFB esters were further derivatized to the dimethylethylsilyl (DMES) ethers, whereby lithocholic acid, deoxycholic acid, chenodeoxycholic acid, ursodeoxycholic acid and cholic acid were distinctly separated by GC on a cross-linked methyl silicone fused-silica capillary column. The detection limit for the PFB-DMES derivatives of dihydroxylated bile acids was 2 fg when the fragment ion was monitored at m/z 563 in the NICI mode using isobutane as a reagent gas.

Bile Acids and Salts↗
PubMed1987

Marked enhancement in antithrombotic activity of isocarbacyclin following its incorporation into lipid microspheres.

Isocarbacyclin, (+)-9(O)-methano-delta 6 (9 alpha)-PGI1 (TEI 7165) and its methyl ester (TEI 9090) were incorporated in lipid microspheres (LM) with a diameter of 0.2 micron, in an attempt to increase their efficacy, possibly by way of targeting the drugs to the site of vascular damage. When the two LM-preparations were incubated in 2% bovine serum albumin solution, it was shown that TEI 7165 was released rapidly from LM, while the release of TEI 9090 was slow. Thus, TEI 9090 in LM, injected intravenously, may not be released largely in plasma before the distribution of LM to the target sites. The antithrombotic activity of the LM preparation of TEI 9090 was then compared with that of TEI 9090 as such in the hamster cheek pouch model. It was found that TEI 9090 incorporated in LM was more than 500 times more potent as an inhibitor of ADP-induced thrombus growth. These data suggest that prostacyclin analogues incorporated in LM may be used safely as potent antithrombotic agents in the clinical application.

Animals↗
PubMed1987

Non-linear pharmacokinetics of aprindine hydrochloride in oral administration.

The pharmacokinetics of oral aprindine hydrochloride (in the following briefly called aprindine; Aspenon) were studied in 38 patients with ventricular premature contractions following single or multiple administration. Oral administration of aprindine in a single dose of 100-150 mg resulted in a mean maximal plasma concentration of 0.77 microgram/ml and a mean elimination half-life of 26.5 h. With multiple oral administration in 10 mg and 20 mg doses at intervals of 8 h, plasma concentration reached a steady state in 1-2 weeks with either dosage rate. Stable plasma concentrations were maintained with little diurnal or day-to-day fluctuation. The mean steady-state minimal plasma concentration with a 10 mg dosage was 0.28 microgram/ml. With a 20 mg dosage, however, this was more than tripled to 0.89 microgram/ml. The elimination process after the final administration of the drug was slower than with single dosage, and deviated from the first-order kinetics to produce a convex curve on a semilogarithmic graph paper. From these results it was apparent that aprindine shows non-linear pharmacokinetic behavior within the therapeutic dosage range.

Administration, Oral↗
PubMed1987

Congenital adrenal hypoplasia, myopathy, and glycerol kinase deficiency: molecular genetic evidence for deletions.

Glycerol kinase deficiency (GKD) is an X-linked recessive trait that occurs in association with congenital adrenal hypoplasia (AH) and developmental delay with or without congenital dystrophic myopathy. Several such patients have recently been reported to have cytological deletions of chromosome region Xp21 and/or of DNA markers that map near the locus for Duchenne muscular dystrophy (DMD) in band Xp21. We have examined the initial family reported in the literature and, using prometaphase chromosome studies and Southern blot analysis with 13 different DNA probes derived from band Xp21, have found no deletions within this region of the X chromosome. When DNA samples from six other unrelated affected males were analyzed, four of them were found to have different-size deletions within Xp21. Thus, the form of GKD associated with AH and dystrophic myopathy exhibits significant genetic heterogeneity at the DNA level. No deletions were detected in two patients with isolated GK deficiency. Comparison of our molecular studies of unrelated patients with deletions of DNA segments allows us to define the region of Xp21 (between probes J-Bir and L1.4) that most likely contains the genes for GKD and AH. This location is distal to the DMD locus. The patients with progressive muscular dystrophy tended to have larger deletions that include markers known to derive from the DMD locus, while GKD/AH/dystrophic-myopathy patients without current evidence of deletion seemed to have a milder, nonprogressive form of congenital myopathy.

Abnormalities, Multiple↗
PubMed1986

[Myocardial imaging of patients with myocardial infarction--investigation of diastolic imaging by ECG-gated study].

ECG-gated thallium (201T1) myocardial diastolic imaging and non-gated imaging were performed in 22 patients with myocardial infarction. These patients were separated into 2 groups according to echocardiographic findings; Group A: the patients with left ventricular diastolic diameter of 5.5 cm and over and left ventricular ejection fraction of 50% and under; Group B: the others. In the patients of Group A, the low perfusion areas could be demonstrated qualitatively and quantitatively by nongated images as well as gated-diastolic images, while in some patients of Group B, low perfusion areas were shown only by gated-diastolic images, which seemed to be useful. The images gated in 100 ms after the peak of R wave in ECG were conformed as diastolic images by echocardiography, and could be obtained within a half or two thirds of the conventional imaging time.

Aged↗
PubMed1986

MY336-a, a novel beta-adrenergic receptor antagonist produced by Streptomyces gabonae.

Streptomyces gabonae KY2234 was found to produce a new compound, MY336-a, which bound to beta-adrenergic receptor. The compound was isolated from the fermentation broth of KY2234. MY336-a showed a high affinity for the beta-receptor, labeled with [3H]dihydroalprenolol in the membrane fractions of rat heart (beta 1-adrenergic receptor) or lung (beta 2-adrenergic receptor), whereas the compound bound very weakly to alpha-adrenergic receptor, labeled with [3H]dihydroergokryptine in rat brain. the inhibition constants (Ki) of the compound were 0.73 and 0.14 microM for the beta-receptors of heart and lung, respectively. 5'-Guanylylimidodiphosphate (Gpp(NH)p) did not alter the affinity of the beta-receptors for MY336-a. In isolated guinea-pig atria, MY336-a produced an inhibition of the positive chronotropic and inotropic effects of isoproterenol. MY336-a also antagonized the relaxation of tone induced by isoproterenol in isolated guinea-pig trachea. No partial agonistic activity was detected in MY336-a in the isolated atria and trachea. In anaesthetized dogs, MY336-a (1 mg/kg, iv) exerted negative inotropic action (left ventricular dp/dt max, -32.6%).

Adrenergic beta-Antagonists↗