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Biomedical subjects

K Matsuda

Publications and source records attributed to K Matsuda.

At least 541 records · Page 30Linked to original sources
PubMed1990

[Study on new quinolone-resistant strains isolated from urine--annual changes of its frequency and the relation to drug volume].

There is concerned that the new quinolone-resistant strains have increased along with its widespread usage. We analysed the annual changes in frequency of ofloxacin-resistant strains isolated from urine in the past four years at two different types of hospitals, department of urology in Sapporo Medical College and Muroran City Hospital, since the usage of these agents seem to be related to the annual changes of the frequencies. The results were summarised as follows: 1) In the two hospitals, drug volume of the new quinolones had been increased, in particular, the past six years from 1984. 2) The annual changes in frequency of ofloxacin-resistant Staphylococcus aureus have been increasing from 0 to 41.2 percent in Sapporo Medical College and 16.7 to 96.7 percent in Muroran City Hospital. The frequency of ofloxacin-resistant Pseudomonas aeruginosa also have been increasing from 24 to 66.7 percent in Sapporo Medical College and 37.5 to 81.8 percent in Muroran City Hospital. 3) The frequency of ofloxacin-resistant indole positive Proteus spp. and Serratia marcescens for four years at Sapporo Medical College (indole positive Proteus spp.: 0-1.8 percent, Serratia marcescens: 10-43 percent) was very different from that at Muroran City Hospital (indole positive Proteus spp.: 65-82 percent, Serratia marcescens: 71-100 percent). The difference seems to be caused by the hospital acquired infection.

4-Quinolones↗
PubMed1990

Fetal breathing, sleep state, and cardiovascular responses to adenosine in sheep.

The possibility that adenosine mediates hypoxic inhibition of fetal breathing and eye movements was tested in nine chronically catheterized fetal sheep (0.8 term). Intracarotid infusion of adenosine (0.25 +/- 0.03 mg.min-1.kg-1) for 1 h to the fetus increased heart rate and hemoglobin concentration but did not significantly affect mean arterial pressure or blood gases. As with hypoxia, adenosine decreased the incidence of rapid eye movements by 55% and the incidence of breathing by 77% without significantly affecting the incidence of low-voltage electrocortical activity. However, with longer (9 h) administration, the incidence of breathing and eye movements returned to normal during the adenosine infusion. Intravenous infusion of theophylline, an adenosine receptor antagonist, prevented most of the reduction in the incidence of breathing and eye movements normally seen during severe hypoxia (delta arterial PO2 = -10 Torr). It is concluded that 1) adenosine likely depresses fetal breathing and eye movements during hypoxia and 2) downregulation of adenosine receptors may contribute to the adaptation of breathing and eye movements during prolonged hypoxia.

Adenosine↗
PubMed1990

Fetal breathing and cardiovascular responses to graded methemoglobinemia in sheep.

Graded methemoglobinemia (MetHb) was produced in unanesthetized fetal sheep to determine the effects on brain oxygenation. MetHb was induced by infusing methemoglobin-containing erythrocytes in exchange for fetal blood. During the hour after MetHb was established, fetal methemoglobin concentrations averaged 1.23 +/- 0.12 (mild MetHb), 1.71 +/- 0.13 (moderate MetHb), and 2.27 +/- 0.17 g/dl (severe MetHb). MetHb reduced mean arterial O2 content by approximately 19 (mild MetHb), 29 (moderate MetHb), and 39% (severe MetHb). The average preductal arterial PO2 fell by 1.6 (-7%), 2.8 (-11%), and 4.0 Torr (-16%) for mild, moderate, and severe MetHb, respectively. Fetal heart rate increased significantly during mild and moderate MetHb, and mean arterial pressure fell slightly during moderate and severe MetHb. The incidences of fetal breathing and eye movements were reduced in a dose-dependent manner when the calculated brain end-capillary PO2 was less than 14 Torr. We conclude that: 1) the effective capillary PO2 in the fetal brain can be significantly reduced by increasing the distance between non-methemoglobin-laden erythrocytes in capillaries and 2) hypoxic inhibition of fetal breathing probably arises from discrete areas of the brain having a PO2 less than 3 Torr.

Animals↗
PubMed1990

Prostaglandin protects isolated guinea pig chief cells against ethanol injury via an increase in diacylglycerol.

We studied cellular processes activated by prostaglandins (PG) that are involved in the protection of gastric chief cell injury estimated in terms of dye exclusion test, release of lactate dehydrogenase (LDH), or 51Cr from prelabeled chief cells. Pretreatment of chief cells with 3 x 10(-6) M PGE2 or PGE1 at 37 degrees C and pH 7.4 for 15 min maximally reduced not only ethanol- but also taurocholic acid-caused LDH release from chief cells. PGs equipotently stimulated increases in the accumulation of diacylglycerol and cyclic AMP without elevating intracellular Ca2+ concentrations in gastric chief cells. The rank order of the potency was equal to that of PGs to reduce the injury. Pretreatment of chief cells with synthetic 1-oleoyl-2-acetyl-sn-glycerol (OAG) or 12-o-tetradecanoyl phorbol 13-acetate (TPA) reduced the injury of chief cells, while 4 alpha-phorbol 12,13-didecanoate, an inactive phorbol ester, failed to reduce the injury and 1-(5-isouinolinylsulfonyl)-2-methylpiperazine (H7) blocked the protective action of PGE2. On the other hand, forskolin and dbcAMP had no effect on ethanol-caused LDH release and diacylglycerol formation in chief cells. These results suggest that PGE2 and PGE1 possess the direct protective action against ethanol- or taurocholic acid-caused injury in chief cells, presumably through the activation of the diacylglycerol/protein kinase C signaling pathway.

Animals↗
PubMed1990

An enzymatic method for the kinetic measurement of L-asparaginase activity and L-asparagine with an ammonia gas-sensing electrode.

A simple kinetic method to assay L-asparaginase and L-asparagine with an ammonia gas-sensing electrode is described. The method is based upon the de-amination of L-asparagine by L-asparaginase from Escherichia coli, resulting in the production of ammonia. The initial rate (mV/min) of ammonia release is proportional to the activity of L-asparaginase and also to the concentration of L-asparagine in the presence of a large amount of the enzyme. Optimal temperature, buffer composition and pH for the assays are specified. L-Asparaginase was determined in the range of 0.4-1.6 U in a 0.1 ml sample; the recovery was 98.1-103.8% for 16 determinations and sigma n was 1.59. L-Asparagine was determined in the concentration range of 1 x 10(-4)--1 x 10(-3) M with sigma n-1 1.92. The method was applied to the determination of 1-5 x 10(-4) M asparagine added to human serum with sigma n-1 1.96 for 5 determinations.

Ammonia↗
PubMed1990

Effects of Z-100 on mice exposed to gamma-irradiation: a preliminary report.

Subcutaneous administration of Z-100 twice a week starting immediately after supralethal whole-body irradiation of mice produced a prolongation of survival time. The effect of Z-100 on the hematopoietic system was thought to have contributed to the prolongation and was thus investigated. A single subcutaneous dose of Z-100 immediately after irradiation inhibited reduction of the total number of nucleated cells in the femoral bone marrow of the treated mice, although the inhibition was not by promotion of the proliferation of specific cells but by promotion of the recovery of multiple cell lines. Treatment with Z-100 promoted colony formation in the spleen of the treated mice and CFU-S formation in the femoral bone marrow, indicating that the drug accelerated the recovery of hematopoietic stem cells. The recovery of CFU-C count was also promoted by Z-100, which suggested that the drug has a restoring effect on the recovery of granulocytic and macrophagic precursor cells. Furthermore, Z-100 produced a greater increase in the CSF activity in the serum of irradiated mice, leading to the presumption that CSF induced by Z-100 was greatly involved in promoting the recovery of the above-mentioned hematopoietic stem cells. We conclude that Z-100 prolonged survival time of irradiated mice by promoting recovery of hematopoiesis of the mice.

Animals↗
PubMed1990

Immunochemical analysis of the glucomannan from Candida utilis.

A glucomannan isolated from a Candida utilis mutant having a new chemotype was further studied by inhibition of the homologous precipitin reaction with oligosaccharides obtained from the glucomannan by partial acid hydrolysis and controlled acetolysis. Oligosaccharides having at least two consecutive alpha-(1----2)-linked mannose residues at the non-reducing end and gluco-manno-pentasaccharide were effective inhibitors. Thus, it appears that the glucomannan had two groups of antigenic determinants, one corresponding to the side chains of two, three, and four mannose units connected by alpha-(1----2)-linkage, and the other corresponding to a side chain composed of an O-alpha-D-glucopyranosyl-(1----6)-O-alpha-D-mannopyranosyl- (1----2)-O-alpha-D-mannopyranosyl-(1----2)-D-mannose unit. These results support a probable structure of repeating units for the glucomannan presented previously. The relative susceptibility of intersaccharidic linkages to acid hydrolysis in the mannan is discussed.

Candida↗
PubMed1990

Reduction of infarct size and infiltration of polymorphonuclear leukocytes by a thromboxane synthetase inhibitor. Studies in a rabbit ischemic heart model.

The effect of sodium 6-(2-(1-(1H)-imidazolyl)methyl-4,5-dihydrobenzo(b) thiophene)carboxylate (RS-5186), a potent and long acting thromboxane synthetase inhibitor in vitro and in vivo, on infarct size and on the infiltration of polymorphonuclear leukocytes (PMNs), was studied in a rabbit coronary artery occlusion (1 h)--reperfusion (0.5 h or 3 h) model. The infarcted region was stained with triphenyltetrazolium, and the ratio of infarcted area/left ventricular area was calculated. The infiltration of PMNs into the infarcted region was determined by measuring the PMNs specific enzyme, myeloperoxidase (MPO) activity. In the vehicle treated group, infarct size and MPO activity were increased with increased reperfusion time from 0.5 h to 3 h (infarct size: 15.3 +/- 2.7 to 25.2 +/- 3.2%; MPO activity: 255 +/- 51 to 825.3 +/- 169.4 units/g wet weight). There was also a significant correlation (r = 0.90, p less than 0.01) between the infarct size and MPO activity. In contrast, in the RS-5186 treated group (2 mg/kg i.v.), both infarct size and MPO activity did not increase with prolongation of the reperfusion period (infarct size: 12.8 +/- 5.5 to 10.3 +/- 3.6%; MPO activity: 318.8 +/- 36.7 to 381.2 +/- 72.6 units/g wet weight). In 0.5 h reperfused samples, there was no significant difference in infarct size or in MPO activity between the vehicle treated group and RS-5186 treated group.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

[Effect of teprenone and H2-receptor antagonists on phosphatidylcholine synthesis in the isolated guinea pig gastric glands].

To better understand the mechanism of phosphatidylcholine synthesis in the stomach, [3H] choline incorporation into phosphatidylcholine in response to the drugs which have been commonly used for treating the patients with gastric ulcer was examined using isolated guinea pig gastric glands. Teprenone stimulated [3H] choline incorporation into phosphatidylcholine in gastric glands, up to 146 +/- 11% of control (n = 6, P less than 0.05). On the other hand famotidine, ranitidine and cimetidine significantly decreased the incorporation to 73 +/- 8%, 72 +/- 11%, 67 +/- 11% of control, respectively (n = 6, P less than 0.05, P less than 0.05, P less than 0.05). When the glands were pulsed with [3H] choline followed by incubation in the presence of teprenone or each H2RA for 180 min to see the effects of the agents on the limiting step of the phosphatidylcholine synthesis, teprenone also significantly stimulated [3H] choline incorporation into phosphatidylcholine, but each H2RA did not affect phosphatidylcholine biosynthesis any more. Teprenone stimulated CTP:phosphocholine cytidylyltransferase (CTF) from a basal value of 0.92 +/- 0.10 to 1.69 +/- 0.39 (nmol/min/mg protein) (n = 3, P less than 0.05). These results suggest that teprenone may stimulate phosphatidylcholine biosynthesis through the activation of CTF, a late-limiting enzyme of PC biosynthesis, and H2RA may affect phosphatidylcholine synthesis by inhibiting choline transport or choline kinase in gastric glands.

Animals↗
PubMed1990

[Effects of ethanol on pepsinogen release from isolated guinea pig gastric chief cells].

The effects of ethanol on pepsinogen release from isolated guinea pig gastric chief cells were investigated. Ethanol, at concentrations of 300 mM to 900 mM, dose-dependently stimulated increases in pepsinogen release, initial Ca influx rate and intracellular free Ca concentration ([Ca2+]i) without affecting chief cells' viability. The increases in all parameters were inhibited by La3+ or EGTA, but not by nifedipine or verapamil. COOH-terminal octapeptide of cholecystokinin (CCK8) also stimulated increases in pepsinogen release, initial Ca influx rate and [Ca2+]i. However, the increases were dependent on not only extracellular Ca2+ but also intracellular Ca2+ mobilization. These results suggest that ethanol stimulates Ca2+ influx via the mechanism different from that of CCK8 and thereby stimulates pepsinogen release from isolated guinea pig gastric chief cells.

Animals↗
PubMed1990

[Cholecystokinin receptors on guinea pig gastric chief cell membranes].

Cholecystokinin (CCK) binding to its receptors on guinea pig gastric chief cell membranes was characterized with 125I-COOH terminal octapeptide of CCK (125I-CCK8). Specific binding of 125I-CCK8 to chief cell membranes was maximal at pH 6.0 and 30 degrees C after 180 min of incubation and reversible upon the addition of 10(-7) M unlabeled CCK8. CCK analogs such as CCK8, gastrin-I, and COOH-terminal tetrapeptide of CCK (CCK4) competitively inhibited the labeled CCK8 binding with the half maximal inhibitory concentration of 10(-10) M, 3 X 10(-7) M and 10(-6) M, respectively. Furthermore, guanine nucleotide analogs such as GTP gamma S and Gpp(NH)p also inhibited the labeled CCK8 binding to chief cell membranes. Scatchard analysis of the binding data at pH 6.0 revealed two orders of the binding sites and GTP gamma S decreased the binding by converting two binding sites of the receptors to only one site of lower affinity. These results suggest that there are specific receptors for CCK, which are coupled to a guanine nucleotide regulatory protein on guiea pig gastric chief cell membranes.

Animals↗
PubMed1990

[Clinicopathological analysis of leiomyosarcomas of the small intestine and a review of the Japanese literature].

An analysis has been made of 9 cases of a leiomyosarcoma of the small intestine that were treated from 1974 through 1989. In two patients (22.2%), a perforation was seen, and a case report of a 59-year-old woman is presented. Further, case reports of leiomyosarcomas in the Japanese literature from 1980 through 1989 were clinico-pathologically analyzed. The frequency of a perforation was found to be 8.6%, and the distribution of the perforated leiomyosarcomas was the same as for the non-perforated cases. The five-year postoperative survival rate was 41.2%. Of note is that 3 out of 10 patients that had survived for 5 years subsequently died of sarcomatosis.

Adult↗
PubMed1990

Feasibility of subclassification of temporal lobe epilepsy (1989): an etiological overview.

Temporal lobe epilepsy with amygdalohippocampal seizures may have episodes of severe convulsions in childhood more frequently and the onset age is significantly lower compared to epilepsy with lateral temporal seizures. To the contrary, tumorous lesions are found more frequently in epilepsy with lateral temporal seizures. In view of the presumed known etiologies in relation to the localization of epileptogenic foci, the Classification of Epileptic Syndrome (1989), subdividing temporal lobe epilepsies into 2 groups, was found to be useful.

Adult↗
PubMed1990

Therapeutic plasmapheresis for post-operative hepatic failure.

It goes without saying that post-surgical hepatic failure must be treated. But today, the prognosis is very poor. The reasons for this are that HF is usually accompanied by hemostatic disorders and PHF, and the patients have fresh wounds and are under surgical stress. Moreover, there is no treatment, except PE, and this requires an anticoagulant. Nafamostat Mesilate (FUT-175) was invented as a serine protease inhibitor. It is short acting, and its degradation does not require the liver. FUT-175 was applied as an anticoagulant to 15 PHF patients with bleeding. There were no side effects and no aggravation of bleeding. Based on these results, FUT-175 is thought to be an ideal anticoagulant.

Anticoagulants↗
PubMed1990

[Surgical treatment of aortic arch aneurysm associated with the aberrant right subclavian artery].

A 64-year-old man, who had an aneurysm of aortic arch associated with the aberrant right subclavian artery, was treated successfully. He was pointed out to have an aneurysm of aortic arch three years ago. Three years later angiograms and computed tomography revealed that it became larger compared with the initial finding. He underwent a replacement of the aortic arch using a woven Dacron graft under open distal method. Aberrant subclavian artery was not involved in the aneurysm. But because the left subclavian artery was involved in it, a woven Dacron graft was interposed between the ascending aorta and left subclavian artery. Postoperative course was uneventful and there were no complications.

Aorta, Thoracic↗
PubMed1989

A fluorescence sandwich ELISA for detecting soluble and cell-associated human interleukin-2.

A fluorescence sandwich ELISA was developed for the quantitation of human interleukin-2 (IL-2) using a combination of two anti-human IL-2 antibodies, L61 and biotinylated anti-IL-2 rabbit IgG. The minimum level of IL-2 detectable by this ELISA was 0.3 pg/ml, indicating that this method is about 100 times more sensitive than the usual colorimetric human IL-2 ELISA. The ELISA specifically detected human IL-2 in cell culture supernatants and serum, and also in extracts from mitogen-stimulated peripheral blood mononuclear cells. All of the IL-2 species detected in the supernatants, sera and cell lysates were shown to have a molecular weight of 15,000, as estimated by size exclusion high performance liquid chromatography.

Animals↗
PubMed1989

Soluble IL-2 receptor in AIDS. Correlation of its serum level with the classification of HIV-induced diseases and its characterization.

By using a fluorescence sandwich ELISA, elevated IL-2R levels were detected in the sera from both HIV-infected hemophiliacs and other HIV-infected patients. The serum IL-2R levels were reflective of the classification of HIV-induced diseases by the Centers for Disease Control. Moreover, the IL-2R levels were negatively correlated most prominently with CD4 cell counts, with lymphocyte counts, and with a decrease in the CD4-CD8 ratio but not with either WBC counts or B cell counts. As striking elevations of serum IL-2R were noted in AIDS patients with group IVD infection, the serum IL-2R was purified sequentially by using size-exclusion HPLC, high-pressure chromatofocusing, and H48 affinity HPLC. The isoelectric point values of IL-2R were separated into 4.2 and 3.8, whereas the Mr was determined to be only 45 kDa by immunoprecipitation with H48 antibody followed by SDS-PAGE. However, production of cellular and supernatant IL-2R was not elevated in PBMC of patients with AIDS or in any of the 19 HIV-I- or HIV-II-infected cell line cells. In contrast, PBMC from patients with adult T cell leukemia and cell line cells that expressed human T cell lymphotropic virus -I or -II produced soluble IL-2R, constitutively. The mechanisms by which serum levels of IL-2R might be elevated in HIV-infected patients are discussed in comparison with that in adult T cell leukemia patients.

Acquired Immunodeficiency Syndrome↗