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T Maseki

Publications and source records attributed to T Maseki.

50 records · Page 3Linked to original sources

[Clinical application of total body retrograde perfusion to aortic dissection operation].

Open distal anastomosis technique proposed by Cooley facilitates operative management of aortic dissection. Usually this procedure is performed under circulatory arrest, therefore, prolonged management is hazardous to cerebral and visceral organ systems. We have utilized profound hypothermia with total body retrograde perfusion: 1) myocardial protection through coronary sinus, 2) cerebral perfusion through superior vena cava with pretreatment of cerebral protective drugs, 3) abdominal visceral perfusion through inferior vena cava). We have obtained good results with this method in consecutive four patients with aortic dissection.

Adolescent↗

Pharmacological properties of contraction caused by sodium removal in muscle strips isolated from canine coronary artery.

Contractions produced by Na+ removal were studied in muscle strips isolated from canine coronary artery. In the presence of 20 mM K+ and 0.5 mM Ca2+, rapid contractions were observed repeatedly on complete replacement of NaCl with sucrose. This contraction in the absence of Na+ (0-Na) was not affected by phentolamine but was strongly inhibited by verapamil. Ouabain slowly potentiated the O-Na contraction and markedly reduced the inhibition due to verapamil. The O-Na contraction was dependent on external Ca2+ both with and without ouabain. Bepridil had effects very similar to those of verapamil. Amiloride and excess Mg2+ reduced the O-Na contraction and the degree of their inhibition was similar after ouabain treatment. The decrease in verapamil susceptibility could suggest that the O-Na contraction has verapamil-sensitive and -insensitive components. The former is probably due to Ca2+ influx through voltage-dependent channels and the latter to Ca2+ influx through an Na(+)-Ca2+ exchange process. Ouabain is considered to increase the contribution of Na(+)-Ca2+ exchange to the O-Na contraction. Mg2+ may inhibit both verapamil-sensitive and -insensitive pathways. Amiloride probably exerts its inhibitory effect on the contractile machinery.

Amiloride↗

[Tricuspid annuloplasty--modified technique].

A modification of the DeVega's tricuspid annuloplasty (TAP) in the treatment of tricuspid regurgitation (TR) is described. Using a double-ended 2-0 Ethibond suture buttered with a Teflon felt pledget, a double suture line is begun at the center of the annulus of the anterior tricuspid valve leaflet. The two suture lines 2 to 3 mm apart are run around the edge of the annular ring of the anterior and posterior tricuspid valve leaflets, going over the posteroseptal commissure by 1.5 cm. A tiny piece of Teflon felt is placed at the end of the sutures. The annulus is narrowed to sungly allow passage of a prove with a diameter of 28 or 30 mm. The tricuspid function is assessed by injecting saline into the right ventricle through the right atrium. Between March 1986 and July 1989, 28 patients with functional TR secondary to mitral valve diseases have been operated on by this technique. There are one early and one late deaths, none being related to tricuspid valve annuloplasty. All 26 survivors had a significant drop in right atrial pressure and an associated improvement in clinical status. Follow-up of the 27 patients who survived this TAP ranges from 2 to 38 months (mean 17 months). This annuloplasty is a safe, effective and readily teachable method for the surgical management of TR.

Adolescent↗

[Effects of cardioplegic solution and calcium entry blockers on coronary artery contraction].

We studied the effects of the electrolyte composition (K, Ca, Na) and calcium entry blockers of the extracellular fluid on the tension development of isolated canine coronary arterial strips. In 20 mEq/l K solution, 4.7 mEq/l calcium produced coronary artery contraction. This Ca-induced contraction was inhibited dose-dependently by calcium entry blockers-nifedipine, nicardipine, diltiazem and verapamil. In the presence of 20 mEq/l K, the reduction of sodium concentration to 12 mEq/l increased the tension of coronary artery. Calcium entry blockers did not affect this tension development. After 5 or 30 min perfusion of calcium entry blockers, Ca-induced contraction was inhibited. It is concluded that low calcium, high sodium cardioplegic solution or addition of calcium entry blockers may relax the canine coronary artery.

Animals↗

[Mitral valvuloplasty for mitral regurgitation due to torn chordae of the posterior leaflet].

Four patients with mitral regurgitation due to torn chordae of the mitral posterior leaflet underwent mitral valvuloplasty. Standard operation was McGoon's procedure which was sometimes combined with Kay's annulorrhaphy. There were no sign of mitral insufficiency and/or stenosis in all patients revealed by the post-operative cardiac catheterization and all of them are on good health. Then, our plans of mitral posterior valvuloplasty for mitral regurgitation are as follows: A resected area is not beyond 33% of the posterior leaflet and the target mitral valve area after valvuloplasty is 2.8 cm2.

Adult↗

pH values of pulp-capping agents.

Calcium hydroxide has been used extensively in dentistry. Few investigators have reported the pH values of pulp-capping agents containing calcium hydroxide. The purpose of this study was to evaluate pH levels of eight pulp capping agents containing calcium hydroxide. The results indicate that the pH values of five capping agents tested are neutralized by the dentin wall, but that three of these capping agents are not neutralized.

Animals↗

[Transvenous permanent pacemaker implantation for Fabry's disease. 3 cases report].

Three men with Fabry's disease (angiokeratoma corporis diffusum universal ) are described. In the first patient, atrial fibrillation appeared, and a permanent cardiac pacemaker (VVI) was implanted. Sick sinus syndrome with complete atrioventricular block was occurred on the second patient. Transvenous pacemaker (DDD) implantation was performed for him. The last patient was younger brother of the second patient. He demonstrated complete atrio-ventricular block, so cardiac pace maker (VAT) was implanted. They showed a low value of granulocyte's alpha-galactosidase activity. During 1 to 4 year follow up period, they showed no trouble about pacemaking. Fabry's disease is an disorder of glycosphingolipid metabolism. This disorder is characterized by the accumulation of trihexosyl ceramide in many sites. Cardiac involvement and abnormal electrocardiographic manifestations are common in this disorder. Permanent cardiac pacemaker is necessary for severe bradycardia caused by this disorder.

Adult↗

[A case of successful surgery for atrial septal defect accompanied with angina pectoris].

A 59-year-old patient with atrial septal defect (ASD) and angina pectoris due to 99% stenosis of the anterior descending coronary artery (LAD) was successfully treated by closure of ASD and coronary artery bypass grafting (CABG) to the LAD #7 with a saphenous vein graft. Preoperatively, the right ventricle was overloaded with high pulmonary arterial pressure (52 mmHg) and anterior segmental wall motion of the left ventricle was reduced probably due to myocardial ischemia. Combined operation, ASD closure and CABG, made these impairments normal and resulted in disappearance of the chest pain and reinstatement to his former job.

Angina Pectoris↗

[Therapeutic evaluation of an ampicillin suppository (KS-R1) used against acute suppurative otitis media in children: a comparison with an oral preparation].

A comparative well-controlled study was performed to evaluate the efficacy and tolerability of KS-R1 (ampicillin rectal suppository, 125 mg X 4/day) administered to the rectum as compared with those of orally administered ampicillin (ABPC) with same dosage. The results obtained were as follows. The clinical effect of the drug was judged in 100 cases (suppository group in 45 cases, oral group in 55 cases) out of 111 cases. The overall efficacy rates evaluated on standard criteria were 93.3% for the suppository group and 89.1% for the oral group. There was no statistically significant difference between 2 groups. Evaluation by stratification according to the dose, disease type and age also revealed a slightly higher efficacy rate on each parameter in the suppository group, but no significant difference between 2 groups. The bacteriological effects evaluated in 84 cases (suppository group in 38 cases, oral group in 46 cases) were 94.7% and 93.5%, respectively. There was no statistically significant difference between 2 groups. Side effects were evaluated in 101 cases (suppository group in 46 cases, oral group in 55 cases), but the incidence rate showed no significant difference between the 2 groups; 3 cases (each 1 of abdominal pain, periproctal redness and periproctal erosion) were observed in suppository group and 2 cases (each 1 of stomach pain + soft stool and diarrhea) in oral group. The results indicate that KS-R1 is equally effective and tolerable against acute suppurative otitis media compared to oral administration of ABPC, and considered to be useful.

Administration, Oral↗