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T Iwasa

Publications and source records attributed to T Iwasa.

At least 55 records · Page 3Linked to original sources
PubMed1989

[Surgical management of pulmonary metastasis from carcinoma of the uterine cervix].

The present study was designed to evaluate the efficacy of surgical management of pulmonary metastasis from carcinoma of the uterine cervix. We saw 609 cases of carcinoma of the uterine cervix from 1979 to 1987, and during the same period also saw 110 cases of recurrent carcinoma of the uterine cervix. Fourteen of these 110 cases were identified as having pulmonary metastasis, and in 11 of 14 cases the recurrent tumors were limited to the lung. Seven of these 11 cases underwent pulmonary resection. Six of the 7 survived more than 2 years after pulmonary resection. Among them, 1 patient has survived more than 4 years, and 1 patient more than 8 years. The tumor cells were thought to metastasize to the lung through the vertebral venous plexus (Batson's plexus) which was suggested as a metastatic route by Thomford et al. in their report on recurrent colon cancer. As a result of this study, if the recurrent tumor is clinically limited to the lung in patients with recurrent carcinoma of the uterine cervix, they should be treated by surgical resection of the pulmonary tumor.

Adenocarcinoma↗
PubMed1989

[The usefulness of Chlamydia testpack for the diagnosis of Chlamydia trachomatis infection in genito-urinary tract].

A comparative study between Chlamydia Testpack and Chlamydiazyme for the detection of chlamydial antigen was performed. In 61 cases suspected of being chlamydial infection, Chlamydia Testpack had a specificity of 92% and a sensitivity of 88% when compared with Chlamydiazyme. On the result of study using Chlamydia trachomatis serotype B, the sensitivity of Chlamydia Testpack which had a lower limit of 6 x 10(4)/ml of EB was less than that of Chlamydiazyme which had a lower limit of 0.7 x 10(4). However, the large number of EB presented in almost all positive specimen, indicated that Chlamydia Testpack could be used to screen the clinical materials.

Adolescent↗
PubMed1988

The mechanism for the inhibitory action of N-(3',4'-dimethoxycinnamoyl)anthranilic acid (tranilast) on the release reaction in platelets.

The molecular basis for the inhibitory action of the antiatopic drug, N-(3',4'-dimethoxycinnamoyl)anthranilic acid (Tranilast), on the thrombin-induced release of a lysosomal enzyme, beta-N-acetylglucosaminidase, from washed rabbit platelets was investigated. Tranilast dose dependently increased cyclic AMP and cyclic GMP levels in thrombin-stimulated platelets, parallel with the inhibition of beta-N-acetylglucosaminidase release. There was no significant effect of Tranilast on adenylate or guanylate cyclase activity. Tranilast inhibited the activity of cyclic AMP and cyclic GMP phosphodiesterases in a cell-free system. The data suggest that the inhibitory action of Tranilast on the release reaction in platelets was due at least in part to inhibition of cyclic nucleotide phosphodiesterases followed by an elevation of cyclic AMP and cyclic GMP levels.

Acetylglucosaminidase↗
PubMed1988

Increment of calmodulin in proportion to enhancement of non-nicotinic responses after preganglionic stimulation of the dog cardiac sympathetic ganglia.

The possible involvement of calmodulin in ganglionic function was investigated. Drugs were given directly into the cardiac sympathetic ganglia through the right subclavian artery (i.a.), unless otherwise stated. Positive chronotropic responses to angiotensin II (0.1 and 0.2 micrograms) were enhanced after repetitive high frequency preganglionic stimulation to the right stellate ganglion. After the stimulation, positive chronotropic responses to bethanechol (2.5, 5 and 10 micrograms), but not those to dimethylphenylpiperazinium (2.5, 5 and 10 micrograms), also were enhanced. The enhancement of response to angiotensin II was not affected by i.v. pretreatment with hexamethonium (40 mg/kg) plus atropine (1 mg/kg) or nifedipine (1 mg/kg). Responses to angiotensin II were not enhanced by A23187 (0.3 mg). The enhanced response to angiotensin II after the stimulation was reduced by the calmodulin antagonists, trifluoperazine (0.1, 0.2 and 0.4 mg) and by N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (0.5, 1 and 2 mg), but not by promethazine (1 mg) and N-(6-aminohexyl)-1-naphthalenesulfonamide (0.5, 1 and 2 mg). The enhanced response to bethanechol after the stimulation also was inhibited by N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide. Pretreatment with N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide before the stimulation prevented development of the enhancement in responses to the peptide. The inhibition of endogenous protein synthesis by cycloheximide, 2.5 or 5 mg/kg i.v. 6 hr before surgical procedures, strongly inhibited development of the enhancement in responses to angiotensin II.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiotensin II↗
PubMed1987

Phosphorylation and inactivation of brain glycogen synthase by a multifunctional calmodulin-dependent protein kinase.

Glycogen synthase was partially purified from canine brain to about 70% purity. The purified enzyme showed differences from the properties of the skeletal muscle enzyme with respect to molecular weights of the holoenzyme and subunit and phosphopeptide mapping. The multifunctional calmodulin-dependent protein kinase from the brain phosphorylated brain glycogen synthase with concomitant inactivation of the enzyme. Although about 1.3 mol of phosphate/mol subunit was maximally incorporated into glycogen synthase, 0.4 mol of phosphate/mol subunit was sufficient for the maximal inactivation of the enzyme. The results indicate that brain glycogen synthase is regulated in a calmodulin-dependent manner similarly to the skeletal muscle enzyme, but that the brain enzyme is different from the skeletal muscle enzyme.

Animals↗
PubMed1987

[Experience of cefuzoname in pediatric patients. Fundamental and clinical investigations].

Cefuzoname (CZON) was administered to 50 pediatric patients with infections, and the efficacy was investigated in 49 patients. The efficacy rate was 83.7% and the drug was evaluated to be highly effective for diseases in the pediatric field. The activity of CZON was especially good against Staphylococcus aureus, and the efficacy rate for 13 clinical isolates was 69.2%, which was comparable to that of cefotiam or cefazolin. CZON appeared to be useable alone in Gram-positive infections. It might be very powerful in the control of infections in secondary immunodeficiency.

Adolescent↗
PubMed1986

Anti-platelet action of an anti-allergic agent, N-(3',4'-dimethoxycinnamoyl)anthranilic acid (tranilast).

The effects of N-(3',4'-dimethoxycinnamoyl)anthranilic acid (Tranilast), a blocker for histamine release from mast cells, on rabbit blood platelet functions were investigated. Tranilast inhibited dose dependently both the release of a lysozomal enzyme, beta-N-acetylglucosaminidase, and aggregation of washed rabbit platelets stimulated by thrombin and collagen. The IC50 was suspected to be 164 +/- 50 microM. The data suggest that Tranilast may be used as an anti-platelet agent in addition to an anti-allergic one.

Acetylglucosaminidase↗
PubMed1986

Purification and characterization of a multifunctional calmodulin-dependent protein kinase from canine myocardial cytosol.

A calmodulin-dependent protein kinase from canine myocardial cytosol was purified 1150-fold to apparent homogeneity with a 1.5% yield. The purified enzyme had a Mr of 550,000 with a sedimentation coefficient of 16.6 S, and showed a single protein band with a Mr of 55,000 (55K protein), determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The purified enzyme had a specific activity of 1.6 mumol/mg protein/min, and Ka values of 67 nM and 1.1 microM for calmodulin and Ca2+, respectively, using chicken gizzard myosin light chain as substrate. Calmodulin bound to the 55K protein. The purified enzyme had a broad substrate specificity. Endogenous proteins including glycogen synthase, phospholamban, and troponin I from the canine heart were phosphorylated by the enzyme. These results suggest that the purified enzyme works as a multifunctional protein kinase in the Ca2+, calmodulin-dependent cellular functions of the canine myocardium, and that the enzyme resembles enzymes detected in the brain, liver, and skeletal muscle.

Animals↗
PubMed1986

Regulation of the actin-activated Mg-ATPase of brain myosin via phosphorylation by the brain Ca2+, calmodulin-dependent protein kinases.

We have previously isolated two Ca2+, calmodulin-dependent protein kinases with molecular weights of 120,000 (120K enzyme) and 640,000 (640K enzyme), respectively, by gel filtration analysis from rat brain. Chicken gizzard myosin light-chain kinase and the 120K enzyme phosphorylated two light chains of brain myosin, whereas the 640K enzyme phosphorylated both the two light chains and the heavy chain. The phosphopeptides of the light chains digested by Staphylococcus aureus V8 protease were similar among chicken gizzard myosin light-chain kinase, the 120K enzyme, and the 640K enzyme. Only the seryl residue in the light chains and the heavy chain was phosphorylated by the enzymes. The phosphorylation of brain myosin by any of these enzymes led to an increase in actin-activated Mg-ATPase activity. The results suggest that brain myosin is regulated by brain Ca2+, calmodulin-dependent protein kinases in a similar but distinct mechanism in comparison with that of smooth muscle myosin.

Actins↗
PubMed1985

Interaction of tyrosine residues with the chromophore in bacteriorhodopsin.

We previously reported that the absorption spectrum at low temperatures of iodinated bacteriorhodopsin can be separated into four components with maxima at shorter wavelengths than in native bacteriorhodopsin. In this study, the time course of the formation of each spectral component after iodination was analyzed, revealing that these four components correspond to four different iodinated states of tyrosine residues interacting with the retinal chromophore of bacteriorhodopsin. Therefore at least two tyrosine residues interact with the chromophore of bacteriorhodopsin.

Bacteriorhodopsins↗
PubMed1985

Identification of a calmodulin-dependent protein kinase in the cardiac cytosol, which phosphorylates phospholamban in the sarcoplasmic reticulum.

A multifunctional calmodulin-dependent protein kinase in the canine cardiac cytosol was purified to near homogeneity. The purified enzyme inactivated glycogen synthase by means of phosphorylation. The enzyme also phosphorylated phospholamban and several other proteins. In view of its physicochemical properties and substrate specificity, the enzyme differed from myosin light chain kinase and phosphorylase kinase, and was considered to belong to a class of similar calmodulin-dependent protein kinases from brain, liver, and skeletal muscle. The results suggest that the enzyme mediates multiple Ca2+-dependent functions in the heart.

Animals↗