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Biomedical subjects

H Katoh

Publications and source records attributed to H Katoh.

At least 487 records · Page 27Linked to original sources
PubMed1981

Regulation of allergic reactions by aerobic Corynebacterium equi extract, CEF. II. Inhibition of Heterologous PCA and antigen-induced histamine release in rats.

A water-soluble fraction (CEF) obtained from Corynebacterium equi was administered intradermally or intravenously into Sprague-Dawley rats. Passive cutaneous anaphylaxis (PCA) was elicited in these rats along with the controls by sensitization with mouse anti-DNP serum and challenge with the corresponding antigen. PCA reactions were markedly inhibited by the pretreatments of the rats with CEF. Similar treatments of the animals 2-4h after the sensitization did not inhibit PCA. Inhibitory activity of CEF in the pretreated animals was shown to be dose-dependent. Incubation of rat peritoneal mast cells with CEF effectively blocked the binding of murine IgE antibodies to the cells as evidenced by the failure of the treated cells to bind the antibodies. Furthermore, antigen-induced histamine release from rat mast cells, which were sensitized with murine IgE antibodies, was reduced significantly by CEF treatment of the cells prior to the sensitization. Results of this study indicated that CEF inhibits the PCA in rats, presumably by blocking the binding of heterocytotropic antibodies to Fc receptor of mast cells.

Aerobiosis↗
PubMed1981

[Clinical studies on 6059-S for acute peritonitis. Clinical effect and tissue concentration (author's transl)].

A new antibiotic drug of oxacephem, with marked resistance to beta-lactamase, 6059-S for parenteral use was tested in 10 patients with acute peritonitis. In 4 cases with appendicitis, 6059-S in a dose of 500 mg was given intramuscularly before operation. In 2 cases with perforate MECKEL'S diverticulitis and intestinal obstruction for right femoral hernia, 6059-S in a dose of 1 g was given by intravenous injection or intravenous drip infusion before or during operation. And in a case with peritonitis after gastrectomy for gastric cancer, 6059-S in a dose of 2 g was given by intravenous drip infusion. Tissue specimens of different sites or body fluids were taken during the operation and from the removed organs. The materials or purulent ascites were subsequently taken at intervals. Determination of 6059-S concentration was performed according to plate agar well bioassay method with Escherichia coli 7437 strain. The peak of 6059-S concentration in purulent ascites of patient with peritonitis for perforate MECKEL'S diverticulitis was 30.5 mcg/ml at 50 min. after 1 g intravenous administration. Concentration of 6059-S in drained pus was 8.38 mcg/ml soon after intravenous drip infusion (2 g, for 2 hrs.). In 10 patients with peritonitis, 6 patients were given 6059-S in a dose of 500 mg by intramuscular administration twice a day, and the serious 4 patients were given in a dose of 1 to 2 g by intravenous drip infusion 1 to 2 times a day. Clinical response was excellent in 6 cases, good in 3 cases, fair in 1 case and poor was none. Any clinical adverse effect was not recognized. On the 6059-S concentration in patients with peritonitis, the concentration in purulent ascites, drained pus and infected tissues were observed higher than the MIC of 6059-S against Escherichia coli and Klebsiella pneumoniae. Therefore 6059-S will be a very useful drug when used for chemotherapy of acute or subacute peritonitis.

Acute Disease↗
PubMed1981

[Clinical studies on 6059-S for biliary tract diseases. Clinical effect and tissue concentration (author's transl)].

A new antibiotic drug of oxacephem, with marked resistance to beta-lactamase, 6059-S for parenteral use was used in 12 patients with acute cholecystitis and cholangitis. 6059-S was given by intramuscular, intravenous or drip intravenous administration at a daily dose of 500 mg to 2 g. Clinical response was excellent in 1 case, good in 10 cases, fair in 1 case and poor in none. Any clinical adverse effect was not recognized. 6059-S is a dose of 500 mg was given by intramuscular administration before the operation to 9 patients. Tissue specimens of different sites were taken from removed organs. The materials of A-bile and B-bile were subsequently taken at intervals. 6059-S concentrations in the A-bile increased after injection and reached to peak from 2 hours to 2.5 hours, then declined very slowly. 6059-S concentration in the B-bile reached to high level of the concentration comparative quickly after intramuscular administration, and it was thought to be excreted through the wall of the gallbladder. 6059-S concentration in the gallbladder wall was directly proportional to the degree of pathological changes of inflammation. On the 6059-S concentration in patients with acute cholecystitis and cholangitis, the concentration in A-bile, B-bile and gallbladder wall were observed higher than the MIC of 6059-S for Escherichia coli and Klebsiella pneumoniae. Therefore 6059-S will be a very useful drug when used for chemotherapy of the infectious diseases of the biliary tract.

Adult↗
PubMed1981

[Clinical studies on tobramycin for infectious diseases following intravenous drip infusion (author's transl)].

An antibiotic drug of aminoglycoside group, tobramycin (TOB) for parenteral use was used to 18 hospitalized patients: 5 with cholecystitis, 10 with acute appendicitis and 3 others. TOB in a dose of 60-90 mg were administered before the operation, 9 cases were administered by intravenous drip infusion for 1-2 hours, 7 cases by intramuscularly and 2 cases by intravenously. The materials of A-bile, B-bile, wall of the gallbladder, the appendix, ascites and serum samples were taken during the operation. TOB concentration was measured by bioassay method with Bacillus subtilis ATCC 6633 strain. TOB concentration in B-bile and gallbladder wall were higher than those in the A-bile. TOB concentration in gallbladder wall and appendix were directly proportional to degree of pathological changes of the inflammation. For the therapeutic purpose, TOB were given to the 15 patients of the above 18 cases. TOB in a dose of 60-90 mg were administered by intravenous drip infusion for 1-2 hours, twice or 3 times a day for 3-18 days. Clinical response was excellent in 2 cases, good in 11 cases, fair in 1 case and poor in 1 case. No adverse effect was observed. Therefore, it was supposed that TOB could be used safety by intravenous drip infusion.

Adult↗
PubMed1981

Calcium-based evaluation of dose-response curves of papaverine-like relaxants in guinea-pig taenia coli.

Using CaCl2 dose-contraction curves in 165.6 mM K(+)- depolarized guinea-pig taenia coli, the maximal contraction level induced by 30 mM CaCl2, and the maximal relaxation level induced by Ca-free solution were treated and 0% and 100% relaxation, respectively. Then four kinds of contraction level were compared: (1) the normal level, (2) 5.5 microns acetylcholine (ACh)-induced contraction, and (3) 1.65 mM ACh- or 3 mM BaCl2-induced contraction in normal solution; and (4) 2.2 and 30 mM CaCl2-induced contraction in K(+) depolarizing solution. The relaxing effects of papaverine, MnCl2, and isoproterenol at these different contraction levels were compared. Papaverine- and MnCl2-induced relaxation of the higher contraction levels [a part of (2), (3) and (4)] seem to reflect a mechanism of the intracellular calcium mobilization, being quite different from relaxation induced by papaverine-like relaxants and isoproterenol at the lower contraction levels [(1) and part of (2)]. The latter phenomenon seems to reflect mechanisms related to cyclic AMP. Papaverine inhibited competitively BaCl2-induced contraction only in K(+) depolarized tissues, suggesting a mechanism of direct reaction with the intracellular Ca store.

Acetylcholine↗
PubMed1978

[Studies on orthodontic polyurethane ringlets. (Part 1) Examination of its physical properties (author's transl)].

The purpose of this study was to develop orthodontic ringlets from polyurethane which have maximum flow resistance. The two types of polyurethane involved were thermoplastic and thermosetting polyurethane. The former included Paraprene 22, 25, 4805 + 4806, Biomer, Elastollan 585 (E-585) and improved Elastollan 590 (E-590). Thermosetting type incorporated Adiprene, Loyler 2170, Colonate 4080 and DC-4978. Using these materials as its base, a ring device was developed. Under two conditions, tests were conducted for tensile strength, aging effects on 50% and 100% modulus and permanent elongation. One group was stored in air at 20 degrees C and the other in water at 37 degrees C. The results were as follows; It was found that the thermoplastic polyurethane possessed high tensile strength. However, the modulus upon aging resulted in a lower reading with the exception of E-590 and Biomer. In the thermosetting polyurethane group, most of the rings except DC-4978 broke down during storage at 100% elongation in water at 37 degrees C. In the case of DC-4978, there was maximum flow resistance. Upon comparing it with E-590 and Biomer, it appeared that DC-4978 was the most effective for orthodontic purposes.

Elasticity↗
PubMed1977

Dormancy and Impotency of Cocklebur Seeds: IV. Effects of Gibberellic Acid, Benzyladenine, Thiourea, and Potassium Nitrate on the Growth of Embryonic Axis and Cotyledon Segments.

Germination of nondormant but impotent small cocklebur seeds (Xanthium pennsylvanicum Wallr.) was promoted profoundly with thiourea or benzyladenine, and slightly with gibberellic acid. Gibberellic acid was ineffective in causing the germination of dormant cocklebur seeds, although thiourea and benzyladenine were effective. Experiments with excised seed pieces showed that the promotive effects of thiourea, benzyladenine, and gibberellic acid on cocklebur seed germination were associated with the enhancement of growth of seed parts; thiourea stimulated predominantly the axial growth, whereas benzyladenine stimulated predominantly the cotyledonary growth.Potassium nitrate or indoleacetic acid had little effect on the initial growth of either axes or cotyledons. Except for gibberellic acid, all of the compounds employed enhanced ethylene production, but in general, the ethylene production seemed more likely to be a consequence of growth rather than a cause of it. We concluded that the chemical regulation of seed germination may be a consequence of the alteration of growth capabilities in either the axes or cotyledons, or both.

Journal Article↗
PubMed1977

Dormancy and Impotency of Cocklebur Seeds: VII. Inability of Dormant Cotyledons to Form Chlorophyll.

Dormant seeds of cocklebur (Xanthium pennsylvanicum Wallr.) were characterized by the lack of ability to form chlorophyll. Such an inability of cotyledons of the dormant seeds was improved by the application of various factors and reagents which were capable of breaking the dormancy and of increasing cotyledon enlargement. Of these, ethylene, benzyladenine, and high temperature treatments were particularly effective, and, in turn, oxygen enrichment, gibberellic acid, thiourea, carbon doxide, and potassium nitrate were also promotive to the greening of the dormant cotyledons. The effects of benzyladenine, oxygen enrichment, and high temperature were reduced in the presence of absorbents for endogenously evolve carbon dioxide and ethylene. delta-Aminolevulinic acid could not restore their greening ability.

Journal Article↗
PubMedDate not supplied

Bleeding esophageal varices associated with pancreatic arteriovenous malformation.

Three cases of bleeding esophageal varices associated with arteriovenous malformation of the pancreas have been observed over the last 7 years. In 1 case, arteriovenous malformation (AVM) was the cause of the portal hypertension; thus, it was considered to be a "primary lesion." In the other cases, liver cirrhosis was the cause of the portal hypertension, and the AVM, which originally was a minor pathology, became significant as the portal hypertension progressed, thus making it a "secondary lesion." In the case of a "primary lesion," resection of the lesion is the preferred treatment for bleeding varices, but our case had multiple lesions, and excision was problematic. In the case of bleeding varices caused by liver cirrhosis, if liver function is normal, surgical treatment of both the varices and the AVM is recommended, while if the liver function is abnormal, repeated sclerotherapy is the best mode of therapy.

Adult↗
PubMedDate not supplied

A novel murine model of aging, Senescence-Accelerated Mouse (SAM).

Senescence-Accelerated Mouse (SAM) has been under development by our research team at Kyoto University since 1970, based on the AKR/J strain donated by the Jackson Laboratory in 1968. The SAM mouse has an accelerated senescence and age-associated pathologies such as senile amyloidosis, senile osteoporosis, degenerative joint disease, cataract, deficits in learning and memory, brain atrophy, hyperinflation of lungs, hearing impairment and so on. SAM research is advancing world-wide and attempts are being made to clarify fundamental mechanisms involved in primary aging processes, pathogenesis of age-associated pathologies and effective methods to modulate or ameliorate the advance of senescence and disease processes involved in age-associated pathologies.

Journal Article↗