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Biomedical subjects

K Takeuchi

Publications and source records attributed to K Takeuchi.

At least 1,243 records · Page 69Linked to original sources
PubMed1983

Effects of an antiulcer drug, sucralfate (a basic aluminum salt of sulfated disaccharide), on experimental gastric lesions and gastric secretion in rats.

The effects of oral sucralfate, a basic aluminum salt of sulfated disaccharide, on various experimental gastric lesions and on gastric secretion were studied in rats. Sucralfate at 300 mg/kg potently inhibited the development of Shay ulcers and indomethacin- and aspirin-induced erosions. The drug at 1000 mg/kg also potently inhibited histamine-induced erosions. Water-immersion stress-induced erosions were inhibited with 1000 mg/kg of the drug, but the degree of inhibition was weaker than that seen in other types of erosion formation. Sucralfate at 1000 mg/kg given twice daily for 14 days significantly accelerated the spontaneous healing of acetic acid-induced ulcers. Sucralfate at over 300 mg/kg tended to increase the volume of gastric juice but had an insignificant effect on acid and pepsin output of pylorus-ligated rats. As a whole, the effects of sucralfate on experimental gastric lesions appear to be much more potent than Maalox, propantheline bromide, and cimetidine. The mechanism of action of sucralfate remains to be determined.

Acetates↗
PubMed1983

Nucleolus-like bodies in embryonal carcinoma cells of the embryoid bodies isolated from mouse teratocarcinoma.

Undifferentiated embryonal carcinoma cells (EC cells) in the embryoid bodies isolated from mouse teratocarcinoma contained nucleolus-like bodies (NLBs) of smaller sizes in their cytoplasm (their sectional area averaged about 0.036 micrometers2). At the onset of EC cell differentiation, the average sectional area of NLBs significantly increased (about 0.107 micrometers2). When EC cells had differentiated into mesenchymal cells and endothelial cells of primitive blood vessels, NLBs decreased dramatically both in size and number. The possible role of NLBs in the differentiation process of EC cells is discussed.

Animals↗
PubMed1983

Natural history of glioma.

The natural life history of gliomas is discussed from the viewpoint of early diagnosis of so-called "silent" gliomas and postoperative follow-up study of "inactive gliomas, both types easily detectable by CT scan. On the basis of their functional status, about 10% of 150 histologically proven intracranial gliomas were judged to be silent or inactive gliomas. They were inactive for an average of 8.5 years, and most were fibrillary or gemistocytic astrocytomas except for one grade 3 astrocytoma. cystic formation was seen in two thirds of the cases and calcification in one half. Also, among highly malignant gliomas, a significant difference in the period of survival was seen between the group with very long intervals of 2-3 years, from onset to operation and that with relatively short periods of 2-3 months. Accordingly, treatment policy regarding such silent or inactive gliomas should be carefully determined case by case. Monitoring during postoperative progression-freed intervals is especially useful.

Astrocytoma↗
PubMed1983

Role of primers in glucan synthesis by glucosyltransferases from Streptococcus mutans strain OMZ176.

The effects of isomaltosaccharides of various molecular weights (isomaltose to dextran T2000) on glucan synthesis by a water-soluble glucan-synthesizing glucosyltransferase enzyme (GTase-S) and a water-insoluble glucan-synthesizing enzyme (GTase-I), both from Streptococcus mutans OMZ176, were examined. The activity of GTase-S was not affected by the addition of the isomaltosaccharides, but GTase-I was stimulated increasingly by isomaltosaccharides with degrees of polymerization more than 10. The GTase-I activity first increased and thereafter decreased slightly with increasing amounts of a soluble dextran. Maximal stimulation occurred at concentrations in the range 0.1 to 0.2 mg ml-1, when dextran T10 was used as a primer. The rate of glucan synthesis was highly enhanced by the combined action of GTase-S and GTase-I. The profile of the net activity of GTase-I in the presence of various amounts of GTase-S was similar to that of GTase-I in the presence of increasing amounts of an exogenous dextran. These results collectively suggest that soluble glucan produced by GTase-S from sucrose acts as an intrinsic primer for the glucan synthesis by GTase-I, indicating the contribution of autopriming in glucan synthesis by crude GTase of S. mutans.

Dextrans↗
PubMed1983

Effects of subchronic treatment of methamphetamine haloperidol on the rat brain levels of GABA, glutamate and aspartate.

Centrally active amino acids (GABA, glutamate, aspartate) were assayed enzyme-fluorometrically in five brain regions of the rat after a 16-day administration of methamphetamine (2.5 mg/kg, i.p.) and haloperidol (2.5 mg/kg, i.p.), or both agents together. Methamphetamine caused no statistically-significant changes in the GABA contents in any brain areas, a significant decrease in the glutamate content of the striatum, hippocampus and midbrain and an increase in the aspartate content of the hypothalamus. Haloperidol treatment resulted in no changes in the GABA content, a significant decrease in the glutamate content of the striatum and a significant increase in the aspartate content in the frontal cortex. The treatment with both agents caused a significant decrease in the GABA content of the hypothalamus. The combined administration normalized a lowering of the glutamate levels in the striatum caused by methamphetamine and haloperidol, respectively, and increased the level of aspartate in the hypothalamus caused by methamphetamine and in the frontal cortex caused by haloperidol.

Animals↗
PubMed1983

Purification and characterization of mucopolysaccharidase from an oral strain of Bacteroides sp.

A mucopolysaccharidase in the cell extract of an oral strain of Bacteroides sp. was purified to homogeneity by ammonium sulfate precipitation, DEAE-cellulose column chromatography, gel filtration on Sephadex G-200, and isoelectric focusing. Specific activity increased 110-fold and recovery was 2%. The molecular weight was determined to be 89,000 by gel filtration, and the isoelectric point was 7.0. The optimum pH for the activity was 6.5. The enzyme was inactivated by heating at 60 degrees C for 5 min. The purified mucopolysaccharidase degraded hyaluronic acid more rapidly than chondroitin and chondroitin sulfate A and C. However, it had no activity against chondroitin sulfate B, heparin, and heparan sulfate. Since unsaturated disaccharides were derived from the enzyme substrate, this enzyme was considered to be a mucopolysaccharide lyase.

Bacteroides↗
PubMed1983

Lactoferrin-deficient neutrophil polymorphonuclear leucocytes in leukaemias: a semiquantitative and ultrastructural cytochemical study.

Semiquantitative analysis of lactoferrin deficiency in neutrophil polymorphonuclear leucocytes in various haematological and non-haematological disease was carried out by scoring polymorphonuclear leucocytes stained for lactoferrin by the immunoperoxidase method. The staining patterns for lactoferrin were classified into four types (0-III) based on the intensity of reaction, and the sum of the ratings of 100 polymorphonuclear leucocytes was considered as "lactoferrin score" with a possible range of 0-300. As a result, significantly low lactoferrin-scores were frequently observed in acute leukaemias and the acute phase of chronic leukaemias. Of 35 cases with leukaemias, lactoferrin-negative polymorphonuclear leucocytes (type 0) were observed in the following cases: eight cases of acute myelogenous leukaemia (8/14), a case of chronic myelogenous leukaemia (1/10) in blast crisis, one of acute promyelocytic leukaemia (1/1), one of acute monocytic leukaemia (1/2), and a case of chronic myelomonocytic leukaemia (1/2) in a transitional phase to an acute myelomonocytic leukaemia. In two cases of acute myelogenous leukaemia, in which the majority of polymorphonuclear leucocytes were negative for lactoferrin, ultrastructural cytochemical study revealed total lack of specific granules in these polymorphonuclear leucocytes. This suggests that lactoferrin is localised in the specific granules of neutrophils as has been postulated previously by others.

Adolescent↗
PubMed1983

Purification and characterization of exo-beta-1,3-glucanase from a hatching supernatant of Strongylocentrotus intermedius.

Exo-beta-1,3-glucanase from the sea urchin embryos was purified 114-fold from the initial hatching supernatant by the following procedures: (a) gel filtration on Sephadex G-100; (b) hydrophobic chromatography on 4-phenylbutylamine-Sepharose (PBA-Sepharose); (c) two ion-exchange chromatographic steps on DEAE-cellulose; (d) gel filtration on Ultrogel AcA 34; (e) gel filtration on Sephadex G-100. The purified enzyme contained 2.2% carbohydrate and gave a single protein band corresponding to a molecular weight of 136 000 following electrophoresis on sodium dodecyl sulfate (SDS) - urea - polyacrylamide gel. Gel filtration on Ultrogel AcA 34 with a nondenaturing solvent gave a molecular weight of 130 000 +/- 6000. The enzyme displayed an optimum pH at 5.0-5.5 and hydrolysed laminarin and PS(curdlan)-beads at the nonreducing ends, releasing glucose. Although activity of the purified enzyme was not affected by SDS, urea, some divalent ions, and 2-mercaptoethanol, both dithiothreitol and Hg2+ were markedly inhibitory.

Animals↗
PubMed1983

Acid back-diffusion and mucosal H+ handling in the rat stomach under normal and stress-induced conditions.

We determined acid back-diffusion and pepsin output simultaneously in vagotomized rats after instillation of HCl into the stomach under normal and stress-induced conditions. With exposure to 6 ml of 100 mM HCl, spontaneous acid back-diffusion increased with the duration of the experiment under both conditions, and the magnitude of the acid back-diffusion was decreased significantly by stress. There was no change in the output of pepsin. While disappearance of luminal acid caused by aspirin or taurocholic acid was not altered by stress, the pepsin output in response to H+ increased significantly in the stressed rats. With exposure to various concentrations of HCl for 3 hr, disappearance of the luminal acid increased linearly with the grade of HCl under both conditions. Except for the concentration of 300 mM, the magnitude of the acid back-diffusion was triple in the normal condition, and the ratio of pepsin output/net flux of H+ was significantly increased by stress. Thus, (1) spontaneous acid back-diffusion decreased with stress, while diffusion induced by chemical barrier breakers remained the same; (2) the action of H+ diffused back into the mucosa did not always parallel the amount of diffusion determined from the loss of H+ in the lumen; (3) intramucosal H+ may be largely dissipated in normal mucosa; and (4) the initiation or aggravation of drug-induced mucosal damages by stress may be related to insufficiency of the H+ dissipating mechanisms.

Animals↗
PubMed1983

Statistical studies on evaluation of mild disturbance of consciousness. Study of a simpler scale for clinical use.

In an effort to express the grades of mild disturbance of consciousness (MDOC), or clouding of consciousness, 25 items were selected for application in clinical examination. Factor analysis of the 25 items revealed that MDOC has a two-factor structure; namely, the performance factor (F1) and the verbal factor (F2). This structure was maintained in the sequential examinations. Guttman's scale analysis showed that the scale using the 25 items may be considered to approximate a unidimensional scale. By item selection according to communality, the 25 items could be reduced to 12 items without losing the two-factor structure or the usefulness and reliability of the examination. The principal component analysis (PCA) score, the F1 score, and the F2 score, calculated from the 12 items, were found to be good scales to describe an overall picture and characteristics of the F1 and the F2 of MDOC, respectively. Furthermore, by means of the characteristic curve (ogive) method, it was revealed that MDOC consisted of four clusters of items, the F2 factor (mild), F1 factor (mild), F2 factor (moderate), and F1 factor (moderate), according to the MDOC severity, so that a simpler scale composed of a representative item from each cluster could be constructed which exhibited a high correlation coefficient with the original PCA score.

Brain Diseases↗
PubMed1983

A new method for measuring cerebrospinal fluid flow in shunts.

An implantable device for measurement of cerebrospinal fluid (CSF) flow in a ventriculoperitoneal shunt tube has been developed. The unit is energized by an extracorporeal high-frequency generator (200 KHz), and electrolysis creates bubbles in the shunt tube. Velocity of bubble flow is detected by a pair of ultrasonic Doppler probes placed a certain distance apart on the skin surface and in parallel with the implanted tube. The CSF flow rate is calculated taking into account velocity and tube diameter, and is expressed in ml/min. The unit consists of a coil with a capacitor, a silicon diode to rectify the high frequency, and a Zener diode to regulate maximum output voltage of 20 V. The output is fed to a pair of platinum electrodes placed inside the unit's tunnel through which the CSF flows. These components are molded in epoxy resin and coated with medical-grade silicone rubber. In animal experiments, CSF flow rates ranging from 0.033 to 1.0 ml/min could be measured by this flowmeter. Clinically, CSF flow has been measured to date in several cases. In two cases of communicating hydrocephalus occurring after the onset of cerebrovascular disease, and in which the CSF flow was continuously monitored for 24 hours, the flow rate ranged between 0.05 and 0.78 ml/min. The CSF flow rate fluctuates in a 24-hour period, increasing in the morning, especially between 12 midnight and 6 a.m., which suggests a circadian rhythm.

Aged↗
PubMed1983

Origin of adult T-cell leukemia virus. Implication for its zoonosis.

Adult T-cell leukemia virus (ATLV) is a retrovirus infecting man. The ATLV genome consists of long terminal repeat (LTR), gag, pol, env and pX sequences and does not carry a typical v-onc gene. The function of the pX sequence is unknown. To search for the origin of ATLV, segments of the ATLV genome were hybridized to DNAs of various species. The sequences homologous to the pX region of ATLV are represented in the genomes of mouse and rat but not in other species including primates and the human. Neither the pol nor U3 sequence of LTR is conserved in any cellular DNA examined. Sequences slightly homologous to the U3R sequence are found in rabbit, chicken and Xenopus. The results suggest that the pX sequence of ATLV might have derived from rodents. Since ATLV can infect primates, rabbit and rat, ATLV might have been prevalent among a wide variety of mammals and exchanged genetic segments (zoonotic) like influenza virus. If we assume that the original host of ATLV is a rodent rather than man, the pX sequence is homologous to host cellular sequences and reminiscent of the v-onc gene although the function of the pX sequence is not clear.

Animals↗
PubMed1983

[On the clinical effects of cefotiam on acute cystitis and changes in form of E. coli in the urine].

Cefotiam (CTM) was administered to female patients suffering from acute cystitis to examine its clinical efficacy and changes in form of the bacteria in urine. CTM was administered to 15 female patients with acute cystitis once a day for three consecutive days (1 g/time in 13 cases, and 0.5 g/time in 2 cases). The overall clinical efficacy was 100%. Bacteriological examination, revealed 13 cases of single infection by E. coli, and one case of E. coli and S. epidermidis (MIC: 0.78 micrograms/ml). MIC of E. coli ranged from 0.05 to 0.78 micrograms/ml. All of the strains were eradicated, the eradication efficacy being 100%. The forms of bacteria in the urine after the administration of CTM were examined in 8 cases (all due to E. coli). Bacteria in urine disappeared or formed a spherical form 5 minutes after the administration of CTM. Disappearance of E. coli was observed in 7 cases at 15 or 30 minutes after drug administration, and with the disappearance, improvements were also observed in the urinary findings. Of these cases, the urinary concentration of CTM was measured in 4 cases. It ranged from 296 to 6,893 micrograms/ml at 5 minutes after the administration. In one case of deficient excretion in urine, filamentation was observed, and with the rise in CTM concentration in urine, granular changes were observed in the shape of bacteria. CTM's excellent clinical efficacy was substantiated by the changes in the form of bacteria in urine.

Acute Disease↗