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Biomedical subjects

A Yoshida

Publications and source records attributed to A Yoshida.

At least 1,027 records · Page 57Linked to original sources

Determination of aldehyde dehydrogenase phenotypes using hair roots: re-examination.

The method for determination of human aldehyde dehydrogenase (ALDH) phenotypes by isoelectric focusing of hair root extracts was re-examined. In order to cancel irregularities stemming from various factors which are not related to the ALDH abnormality and to obtain reproducible results, the sample size for isoelectric focusing should be adjusted using mitochondrial malate dehydrogenase or isocitrate dehydrogenase as an internal reference.

Aldehyde Dehydrogenase↗

Carcinoid tumor of the uterine cervix. A light and electron microscopic study.

A case of carcinoid tumor of the uterine cervix is reported. The patient was a 76-year-old Japanese woman with a complaint of vaginal bleeding. She was clinically diagnosed as stage IVb carcinoma of the uterine cervix. Light microscopically, the tumor was characterized by formation of solid cell nests and, in limited areas, glandular structures. The tumor cells in solid cells nests showed positive argyrophil reaction but were negative for argentaffin reaction. At the ultrastructural level, the cytoplasm of the tumor cells contain numerous neurosecretory granules, microfilaments and well-developed Golgi complexes. On the bases of histochemical and electron microscopic features of tumor cells, the tumor was diagnosed as carcinoid tumor of the uterine cervix.

Aged↗

Ventilatory and heart rate responses to hypoxia in well-trained judo athletes.

Twenty-four active judo athletes were examined by an isocapnic progressive hypoxia test. The results of ventilatory and heart rate responses to hypoxia were analyzed by the hyperbolic equations, VE = VO + AVE/(PETO2 - CVE) and HR = HRO + AHR/(PETO2 - CHR), respectively, where VE and HR are observed ventilation and heart rate, VO and HRO the horizontal asymptote in ventilation and heart rate for infinite end-tidal PO2 (PETO2), AVE and AHR the slope constant indicating the magnitude of hypoxic sensitivity, and CVE and CHR the vertical asymptote in PETO2 for infinite ventilation and heart rate. AVE was further re-calculated after VE was normalized for a 70 kg body mass, using an allometric coefficient, and was defined as AVEN. 1) AVE and AVEN significantly increased with increasing body weight (BW) as has been reported previously, but no such correlation was found between AHR and BW. 2) VO2 at rest was found to be positively correlated with AVE and AVEN but not with AHR. 3) The relationship between AVE and AHR was not significant. Thus, the characteristic feature seen in hypoxic ventilatory activity was not accompanied by a similar trend in heart rate response.

Adolescent↗

Ultrastructure of mammary carcinomas in male rats induced by 7,12-dimethylbenz(a)anthracene.

The morphology of mammary tumors induced by 7,12-dimethylbenz(a)anthracene in male rats was investigated by light and electron microscopy. All tumors induced in male rats were carcinomas with prominent epithelial growth which shows a medullary or cribriform appearance. Neither mammary dysplasias nor fibroadenomas were induced in male rats. Foci of adenoid cystic carcinoma were encountered in some parts of tumors. Papillary and/or tubular patterns, which have been observed frequently in mammary carcinomas in female rats, were not prominent histologic features in male rats. Secretory activity was not remarkable. The morphology of mammary carcinomas in male rats was unchanged in primary and transplanted tumors under various hormonal conditions. This finding supports our previously published results that the mammary carcinomas in male rats are hormone-independent, although our previous biochemical study revealed that the tumors contain both estrogen and estrogen-dependent progesterone receptors.

9,10-Dimethyl-1,2-benzanthracene↗

Sequence of the promoter region of the gene for human X-linked 3-phosphoglycerate kinase.

We have determined the sequence of an 812-bp BamHI-EcoRI restriction fragment containing the 5' region of the human gene for PGK (3-phosphoglycerate kinase or ATP:3-phospho-D-glycerate 1-phosphotransferase; EC 2.7.2.3). The fragment contains 450 bp 5' to three start points for transcription (located by primer extension and S1 nuclease mapping), a leader sequence 85-94 bp long, the first exon of gene (65 bp), and part of the first intron. The promoter region is extremely G + C-rich, lacks a TATA box, and has an 8-bp direct repeat. A comparison of the promoter region for PGK with other promoters on the X-chromosome reveals homology with the promoter for HPRT, but not with the operator for factor IX.

Base Sequence↗

Severe proliferative vitreoretinopathy and retinal detachment. II. Surgical results with scleral buckling.

Prior to the era of vitrectomy, scleral buckling was used to treat 521 eyes with total retinal detachment and proliferative vitreoretinopathy (PVR) of various degrees of severity. The retina was reattached for at least six months in 46.9% of eyes; the anatomic success rate decreased with increasing severity of PVR. Within each grade of PVR, the reattachment rate was higher for eyes with smaller breaks than for eyes with larger breaks, and the prognosis was not worse when smaller breaks were found than when no breaks were found. The cumulative success rate rose with increasing number of reoperations. None of the anatomically successful cases had a final visual acuity of no light perception; 82.9% of them achieved a visual acuity of counting fingers or better. The prognosis for visual improvement after successful scleral buckling was unrelated to the preoperative severity of PVR. Severe intraoperative complications occurred in 5.0% of the eyes, all of which resulted in failure.

Eye Diseases↗

Severe proliferative vitreoretinopathy and retinal detachment. I. Initial clinical findings.

We studied 716 eyes of 697 patients with retinal detachment associated with the more advanced stages of proliferative vitreoretinopathy (PVR). The factors that influenced the severity of PVR and our criteria for surgical treatment were analyzed using statistical methods. The more severe cases of PVR showed a higher prevalence of cases with (1) retinal detachment exceeding 12 months' duration, (2) no retinal breaks observed, (3) the largest retinal break of a size equal to or exceeding one clock hour, and (4) poor initial visual acuity. Compared with the unoperated group, the eyes on which we subsequently operated were characterized by a greater prevalence of (1) patients with bilateral retinal detachment complicated by PVR, (2) cases with relatively recent onset of retinal detachment, (3) phakic eyes, (4) eyes without vitreous hemorrhage, (5) eyes with one or more visible retinal breaks and with smaller breaks, (6) relatively better initial visual acuity, and (7) less severe degrees of PVR.

Eye Diseases↗

Effects of diltiazem on plasma level and urinary excretion of digoxin in healthy subjects.

To evaluate a possible effect of diltiazem hydrochloride (DTZ) on digoxin (DX) kinetics, we performed a study in which a single oral dose of DX (0.5 or 0.75 mg) was given with and without DTZ (30 mg three times daily for 1 wk) to six healthy subjects. DTZ increased plasma DX concentrations at 3, 4, 6, and 12 hr and decreased renal clearance of DX from 3.05 +/- 0.126 to 2.31 +/- 0.234 ml/min/kg. There was no significant change in absorption t 1/2, peak concentration, peak concentration time, distribution t 1/2, biologic elimination t 1/2, or apparent volume of distribution with DTZ.

Absorption↗

Molecular abnormality of an inactive aldehyde dehydrogenase variant commonly found in Orientals.

Usual human livers contain two major aldehyde dehydrogenase [(ALDH) aldehyde:NAD+ oxidoreductase] isozymes--i.e., a cytosolic ALDH1 component and a mitochondrial ALDH2 component--whereas approximately equal to 50% of Orientals are "atypical" and have only the ALDH1 isozyme and are missing the ALDH2 isozyme. We previously demonstrated that atypical livers contain an enzymatically inactive but immunologically crossreactive material (CRM) corresponding to the ALDH2 component. The enzymatically active ALDH2 obtained from a usual liver and the CRM obtained from an atypical liver were reduced, S-carboxymethylated, and digested by trypsin. Separation of their digests by high-performance reverse-phase chromatography and by two-dimensional paper chromatography and electrophoresis revealed that ALDH2 contained a peptide sequence of -Glu-Leu-Gly-Glu-Ala-Gly-Leu-Gln-Ala-Asn-Val-Gln-Val-Lys- and that the glutamine adjacent to lysine was substituted by lysine in CRM. All other tryptic peptides, including eight peptides containing S-carboxymethylcysteine, were common in ALDH2 and CRM. It is concluded that a point mutation in the human ALDH2 locus produced the glutamine leads to lysine substitution and enzyme inactivation.

Aldehyde Dehydrogenase↗

Biochemical evidence that secretor gene, Se, is a structural gene encoding a specific fucosyltransferase.

Nonsecretors have no ABH blood group substances in their saliva and milk, but their erythrocytes contain the blood group substances. It has been generally believed that the secretor gene, Se, is a regulatory gene, not a structural gene, controlling the expression of (alpha 1----2)fucosyltransferase, which synthesizes the blood group H substance from its precursor, in secretions. To account for the existence of the blood type of "para Bombay" phenotype--i.e., H-negative in erythrocytes but H-positive in secretory fluids, another regulatory gene, Z, which would regulate the expression of the enzyme in the hematopoietic tissues, has been proposed. Contrary to this, a more simple model, in which the H gene and Se gene are both structural genes, encoding two separate fucosyltransferases in different tissues, was recently proposed. To settle the controversy, (alpha 1----2)fucosyltransferases were partially purified from human plasma and milk. The two enzymes differed from each other in the following respects: (i) the milk enzyme adsorbed to SP-Sephadex at pH 6.0, while the plasma enzyme did not; (ii) pH-activity profiles, with phenyl beta-D-galactoside as an acceptor, differed between the two enzymes; (iii) the milk enzyme exhibited lower thermal stability than the plasma enzyme; and (iv) Km values for several oligosaccharides with Gal(beta 1----3)GlcNAc and Gal(beta 1----4)GlcNAc as acceptors differed between the two enzymes. These results support the model that the Se gene is a structural gene encoding a distinctive (alpha 1----2)fucosyltransferase, refuting the classical regulatory gene model for the Se locus. The anomeric configuration of the fucosylated galactose residue produced by the action of enzyme was identified, thus establishing the specificity of the enzyme.

Female↗

Malignant lymphoma of the parotid gland with monoclonal cytoplasmic immunoglobulin.

A 56-year-old Japanese man with a malignant lymphoma of the parotid gland was reported. The tumor was located in the superficial lobe of the parotid gland, and somewhat invaded the surrounding soft tissues, but the regional lymph nodes were not involved. Histologically, the tumor was composed of round cells with plasmacytoid configurations and small lymphocytes. The plasmacytoid cells showed eccentric nuclei with fairly marked irregularities and perinuclearr halos. In a large number of tumor cells, a monoclonal cytoplasmic immunoglobulin (CIg), IgG-Kappa type, was demonstrated by the PAP method. Ultrastructurally, some of the tumor cells showed well-developed endoplasmic reticulum. From these findings, this tumor was diagnosed as a diffuse B-cell lymphoma, mainly composed of lymphoplasmacytoid cells. And this tumor may bear a similar nature to an extramedullary plasmacytoma of the classical terminology. Malignant lymphoma of the parotid gland is rare but a case with the demonstration of monoclonal CIg is considered very rare.

Female↗

Augmentation of CO2 drives by chlormadinone acetate, a synthetic progesterone.

We studied 10 male subjects who were administered chlormadinone acetate (CMA), a potent synthetic progesterone, to clarify the physiological basis of its respiratory effects. Arterial blood gas tension, resting ventilation, and respiratory drive assessed by ventilatory and occlusion pressure response to CO2 with and without inspiratory flow-resistive loading were measured before and 4 wk after CMA administration. In all subjects, arterial PCO2 decreased significantly by 5.7 +/- 0.6 (SE) Torr with an increase in minute ventilation by 1.8 +/- 0.6 l X min-1, whereas no significant changes were seen in O2 uptake. During unloaded conditions, both slopes of occlusion pressure and ventilatory response to CO2 increased, being statistically significant in the former but showing nonsignificant trends in the latter. Furthermore, inspiratory flow-resistive loading (16 cmH2O X l(-1) X s) increased both slopes more markedly after CMA. The magnitudes of load compensation, assessed by the ratio of loaded to unloaded slope of the occlusion pressure response curve, were increased significantly. We concluded CMA is a potent respiratory stimulant that increases the CO2 chemosensitivity and neuromechanical drives in the load-compensation mechanism.

Aged↗

A glucose-6-phosphate dehydrogenase variant, Gd(-) Santamaria found in Costa Rica.

Red cell glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-chromosomal-linked abnormality often associated with hemolytic anemia. The G6PD variants obtained from 2 unrelated males, one associated with enzyme deficiency and history of hemolytic jaundice, and the other associated with enzyme deficiency but no hemolytic problems, were examined. Although the 2 subjects have no known consanguinity, the two enzymes could not be distinguished from each other in respect to their electrophoretic mobilities and kinetic properties, both exhibiting slower than normal anodal electrophoretic mobility, lower Km for G6P and NADP and higher rate of utilization of 2-deoxy-G6P and deamino-NADP. An unique double-banded pattern was observed in starch gel electrophoresis at pH 7.0 and pH 8.6. The variant is distinguished from all reported Gd variants, and it is designated Gd(-) Santamaria.

Adult↗

Effects of diltiazem on plasma and tissue digoxin levels in mice.

Effects of diltiazem hydrochloride (DTZ) on digoxin (DX) concentrations in plasma and tissues (brain, heart, liver, and kidney) were studied in mice, and the effects were compared with those of quinidine sulfate (QD). When DX (0.2 mg/kg) was coadministered with DTZ (60 mg/kg) orally for 5 d to mice, plasma DX concentrations were increased significantly as with QD (100 mg/kg). Tissue DX concentrations were also increased in brain, heart, and liver. However, the DX tissue/plasma concentration (T/P) ratios for brain, heart, and kidney were rather decreased with DTZ or QD. The increased plasma and tissue DX concentrations and the decreased T/P ratios with DTZ might be responsible for both the displacement of tissue DX binding and reduced DX elimination as with QD.

Animals↗

Meningioma of the parapharyngeal space: a unique extension of intracranial tumor.

A 45-year-old woman with a meningioma growing in the parapharyngeal space is reported. Her initial symptom was a stuffy feeling in the right ear and swelling of the right parapharynx. The parapharyngeal mass was biopsied, and a frozen section diagnosis suggested a paraganglioma. On electron microscopy, however, the tumor cells failed to show secretory granules, and represented a prominent interdigitation of the cytoplasm with occasional desmosomal attachments. Based on these features the tumor was diagnosed as a meningioma. Thereafter a mass lesion in the temporal lobe of the brain was detected by computerized tomography of the brain. The extracranial extension of the meningioma may occur in some occasions, but such cases in which the infiltrative portion in the parapharyngeal space was initially discovered have been rarely reported.

Diagnosis, Differential↗

Lipoprotein lipase-like activity in the liver of mice with Sarcoma 180.

The triglyceride lipase (TGL) activity of liver homogenates of mice with Sarcoma 180 was measured. The liver homogenate of normal or tumor-bearing mice was treated with 0.25% Triton X-100 and centrifuged at 100,000 g for 60 min, and the supernatant was applied to a heparin-Sepharose column. In normal mice, most of the TGL activities in the supernatant was eluted with 0.75 M NaCl from the column. In mice with Sarcoma 180, the TGL gave two peaks on heparin-Sepharose column chromatography, which were eluted with 0.75 M and 1.5 M NaCl, respectively. The activity in the first peak (0.75 M NaCl eluate) decreased; that in the second peak (1.5 M NaCl eluate) increased, and the ratio of the second peak to the first peak increased during tumor development. The livers of normal mice and mice on day 10 after tumor inoculation were perfused with heparin. The highest rate of the TGL release occurred within 1 min of heparin perfusion, and the bulk of heparin-releasable activity appeared within 2 min of perfusion in both normal and tumor-bearing mice. The TGL activity in liver perfusate of tumor-bearing mice, as well as that of liver homogenate, was resolved on a heparin-Sepharose column into two peaks, which were eluted with 0.75 M and 1.5 M NaCl, and most of the activity was eluted with 1.5 M NaCl. The nature of the TGL activity eluted from a heparin-Sepharose column was investigated. In both liver homogenates and liver perfusates, the first peak did not require serum for maximal activity and was relatively resistant to a high concentration of NaCl or protamine sulfate.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗