Search PubMed⌕ Search

Biomedical subjects

Y Kito

Publications and source records attributed to Y Kito.

At least 55 records · Page 3Linked to original sources
PubMed1994

Cox maze procedure for chronic atrial fibrillation associated with mitral valve disease.

Between April 1992 and October 1993, we combined a modified maze procedure with mitral valve repair (n = 26) or replacement (n = 36) in 62 patients with atrial fibrillation, including 16 patients undergoing reoperation. Associated procedures included aortic valve operation (n = 22), tricuspid annuloplasty (n = 28), atrial plication (n = 10), and others (n = 3). Duration of atrial fibrillation varied from 0.1 to 23 years (average 8.3 +/- 6.4 years), the f-wave voltage ranged from 0 to 0.45 mV (0.16 +/- 0.09 mV), and cardiothoracic ratio varied from 46% to 85% (64% +/- 9%). We modified the maze atriotomies to preserve the sinus node artery and used cryoablation to simplify procedures. Aortic crossclamp time was 142 +/- 25 minutes and cardiopulmonary bypass time 226 +/- 34 minutes. No early or late deaths occurred in a total of 783 patient-months of follow-up. In 52 patients (84%) who regained atrial rhythm, an atrial A-wave was detected in 84% for transtricuspid flow and in 71% for transmitral flow. One patient with sinus rhythm had an episode of transient neurologic ischemia 4 months after mechanical valve implantation. The 10 patients who remained in atrial fibrillation had preoperative fibrillation for a significantly longer time than the rest of the patients with atrial rhythm (14.8 versus 7.2 years p < 0.001) and a larger left atrial dimension (70 versus 58 mm, p < 0.01). Nonetheless, no variable alone could have predicted postoperative rhythm for individual patients. The results suggest that the maze procedure is safe and effective and therefore should be considered for patients with chronic atrial fibrillation undergoing mitral valve operations.

Adult↗
PubMed1994

Short-term outcome of a new modification of the Bentall operation: Carrel patch and inclusion technique.

Leakage around the coronary ostia continues to be the major complication of composite graft replacement of the ascending aorta and aortic valve. To reinforce coronary anastomosis and reduce the operating time, a new modification of the Bentall operation was developed. This procedure involves dissecting full-thickness coronary buttons while leaving the epicardium on the aortic wall and complete wrap of the composite graft by the tailored aortic wall (Carrel patch and inclusion technique). Since March 1983, this approach has been performed in 12 patients (group A) and other Bentall-type operations in 22 (group B). Time affected by haemostasis was 28 min less in group A than in B (P = 0.23). Blood loss and blood transfusion during surgery and hospitalization were significantly lower in group A than B. Significantly less leakage occurred in group A than in B. On the basis of these short-term results, the Carrel patch and inclusion technique is considered to be an accurate time- and blood-saving procedure.

Adult↗
PubMed1994

[Clinical analysis of second CABG].

We performed 1,560 coronary artery bypass grafting (CABG) at National Cardiovascular Center between November 1977 and August 1993. Of those, 41 patients received second CABG, 2 pts. received third CABG and 97 pts. received percutaneous transluminal coronary angioplasties (PTCA). We conducted a retrospective analysis of these patients to determine whether a previous CABG or CABGs affects the results. The hospital death rate was 10% (4/41) for re CABG, 50% (1/2) for third CABG and 0% for PTCA. In second CABG, 3-year cardiac event free rate was 58-68%, and early graft patent rate for new native lesion was high (97%, 28/29). However, the rate was low in graft to the site of the vessel which had occluded within 3 months after first CABG (59%, 7/12). Emergent or urgent operations performed in 14 cases (34%). In PTCA for SVG lesion (33 pts.), 14 (42%) patients received re PTCA and 6 (18%) had second CABG. These data indicated that the results of second CABG were affected by timing of the operation and the site of grafting. We believed that re operation to early occlusion site within 3 months should be performed carefully and further investigation is warranted.

Angina Pectoris↗
PubMed1994

[Effects of subcutaneous administration of erythropoietin on autologous blood predonation in open heart surgery: Japanese multicenter double-blinded dose-study].

The effects of subcutaneous administration of recombinant human erythropoietin (EPO) on harvesting autologous blood predonation (ABP) and decreasing homologous blood transfusion (HBT) in open-heart surgery were examined prospectively in 132 patients treated in a 32-institute multicenter study. Single doses of 6000, 12,000, 18,000 and 24,000 unit (IU) of EPO with intravenous iron (40 mg) were administered once a week for 3 weeks with ABP (400 ml/week) before surgery. ABP volume (ml), change of blood hemoglobin level (C-Hb), preoperative net blood hemoglobin increase (delta Hb [g/dl] including ABP, perioperative blood loss (ml), and HBT rate, were as follows; [table: see text] Preoperative reduction of Hb (C-Hb) was less in administration dose of 18,000 IU and 24,000 IU than 6000 IU (p < 0.05). The increase of delta Hb was highest in 18,000 IU and HBT rate was lowest in administration dose of 24,000 IU, however, there was no statistical difference. In conclusion, both 18,000 IU and 24,000 IU of EPO treatment is effective to minimize the progression of anemia according to ABP for open heart surgery.

Blood Transfusion, Autologous↗
PubMed1993

Isolation and nucleotide sequences of the genes encoding killer toxins from Hansenula mrakii and H. saturnus.

The HMK gene, encoding a killer toxin (HMK) of Hansenula mrakii strain IFO 0895, and the HSK gene, encoding a killer toxin (HSK) of H. saturnus strain IFO 0117, were cloned and sequenced. The HMK and HSK genes encode precursors to killer toxins of 125 amino acids (aa) and 124 aa, respectively. Both precursors have an N-terminal signal sequence of 37 aa which may be removed by a signal peptidase, and a propeptide which may be cleaved off by a KEX2-like protease. There is extensive homology between the aa sequences of HMK and HSK with the exception of the addition of one aa residue in HMK. The HMK and HSK genes were placed, separately, downstream from the yeast GAL10 promoter and introduced into a mutant of Saccharomyces cerevisiae that was resistant to the HMK. The transformants were capable of killing sensitive yeasts in medium that contained galactose with killing spectra similar to those of the donor strains of the toxins. These observations suggest that both killer toxins were synthesized and secreted from S. cerevisiae cells and killed sensitive yeasts, perhaps by the same mechanism as that associated with the donor strains and, moreover, that the difference in primary structure between the two toxins is responsible for the difference in their killing spectra.

Amino Acid Sequence↗
PubMed1993

Structural features of a polygalacturonase gene cloned from Aspergillus oryzae KBN616.

A genomic gene encoding a polygalacturonase from Aspergillus oryzae, used in soy sauce production, was cloned and sequenced. The structural gene comprises 1227 bp coding for 363 amino acids with a putative prepropeptide of 28 amino acids and the open reading frame is disrupted by two short introns of 57 bp and 81 bp. The deduced amino acid sequence of the mature protein showed 63, 63, 63 and 64% homology with those of Aspergillus niger polygalacturonase I, Aspergillus niger polygalacturonase II, Aspergillus tubingensis polygalacturonase II and Cochliobolus carbonum polygalacturonase, respectively. There is, however, little homology among fungal, plant and bacterial polygalacturonases.

Amino Acid Sequence↗
PubMed1993

Immunochemical detection of GTP-binding protein in cephalopod photoreceptors by anti-peptide antibodies.

We prepared polyclonal antibodies (Pab) against the following peptides: partial sequences of bovine transducin alpha subunit including the ADP-ribosylation sites sensitive to cholera toxin (CTX) and pertussis toxin (PTX) and the N-terminus of Drosophila GTP-binding protein q alpha (DGqN); Pab CTX, Pab PTX and Pab DGqN, respectively. These antibodies were specific to the peptides used as antigen and no crossreactivity was observed. Pab CTX and Pab PTX reacted with bovine transducin alpha subunit and the reactivity was lost by preincubation with the specific antigen peptide. Proteins of 41-42 kDa in octopus and squid photoreceptor membranes were recognized by Pab DGqN but not by Pab CTX or Pab PTX. Anti-alpha antibody (GA/1) reacted with the same bands as Pab DGqN recognized. These results suggest that the major GTP-binding protein in cephalopod photoreceptors is a Gq-type, similar to Drosophila Gq.

Amino Acid Sequence↗
PubMed1993

[The effect of LDL-apheresis on the long-term prognosis of hypercholesterolemic patients with coronary artery bypass grafts: a multicenter study].

Hypercholesterolemia is well known as a risk factor which had been shown to affect the long-term prognosis after coronary artery bypass grafting (CABG). The data were collected from multi-institutions documenting the long-term results of CABG in 61 hypercholesterolemic patients who received LDL-apheresis. Mean post-CABG period was 50 +/- 34 (+/- SD) months. Mean period of therapy by LDL-apheresis using Liposorber system after CABG was 25 +/- 17 months with a frequency of once per 2.6 +/- 1.3 weeks. Before initiating LDL-apheresis mean serum cholesterol (TC) and LDL-cholesterol (LDL-C) were 327 mg/dl and 261 mg/dl, respectively. With combined LDL-apheresis and lipid-lowering drug therapy mean TC and LDL-C were reduced to 247 mg/dl and 177 mg/dl immediately pre-apheresis and 106 mg/dl and 60 mg/dl immediately post-apheresis, respectively. Two of 61 patients had PTCA post CABG. Percent free from cardiac event during the long-term period post CABG as calculated by the life-table method was 97% at 3 years and 94% at 4 years and thereafter. While number of the patients is still small, the aggressive cholesterol-lowering therapy by LDL-apheresis is suggested to improve the prognosis of hypercholesterolemic patients with bypass grafts.

Adult↗
PubMed1992

Effects of intraaortic balloon pumping on mitral flow dynamics in patients with coronary artery bypass operations.

We evaluated the improvement in left ventricular function in 26 patients after coronary artery bypass grafting who were treated with intraaortic balloon pumping (IABP). Mitral flow velocity-time integral in the rapid filling phase (IntR) and that in the atrial contraction phase (IntA), the sum of IntR and IntA (IntR+IntA), and the ratio of IntA to IntR (IntA/IntR) were calculated with patients on and off balloon pumping (IABP ON-OFF test). IABP increased IntR and IntR+IntA, decreased IntA/IntR, and did not change IntA, suggesting that a decreased afterload or augmented coronary perfusion improves left ventricular relaxation. When the balloon inflated on every other beat (IABP 1:2 test), IntR and IntR+IntA increased without balloon assist, IntA/IntR decreased off IABP, and IntA did not change. The afterload reduction or augmented coronary perfusion on the previous beat with IABP might help ventricular filling on the next beat without balloon assist. A drastic decrease in IntR after IABP stopped indicated the need to continue IABP. Since the change in IntR during IABP ON-OFF test was significantly correlated with that in IntR during IABP 1:2 test, the change in IntR during IABP 1:2 test could help to predict the optimal time of weaning.

Aged↗
PubMed1992

The absorbance spectrum and photosensitivity of a new synthetic "visual pigment" based on 4-hydroxyretinal.

The firefly squid, Watasenia scintillans, is the only animal known to possess a visual pigment in which the chromophore is 4-hydroxyretinal. This paper describes the absorbance spectrum and some properties of a synthetic "A4" visual pigment generated from bovine opsin and 4-hydroxyretinal. The absorbance spectrum of this pigment is compared with (a) bovine rhodopsin and (b) a rhodopsin template with the same lambda max as the synthetic visual pigment. The A4 pigment is shown to have an absorbance spectrum that is almost identical to that of a rhodopsin template. It is also shown that the photosensitivity and thermal stability of the A4 pigment, dispersed in detergent micelles, is essentially similar to that of rhodopsin.

Animals↗
PubMed1992

An orange-shaped aortic root aneurysm in aortitis syndrome with severe aortic regurgitation.

A 57-year-old man, who had undergone aorto-coronary bypass surgery 4 years before when the shape of the ascending aorta had been normal, had a unique orange-shaped aortic root aneurysm associated with severe aortic regurgitation and congestive heart failure. Replacement of the aneurysm and the aortic valve was successfully carried out, and histopathological examination revealed that the aneurysm was caused by aortitis syndrome.

Aorta, Thoracic↗
PubMed1992

[Surgical decisions for active infective endocarditis in patients with acute neurological complications].

The surgical management of 7 patients with active infective endocarditis and recent (within 16 days) neurological injury was presented. All patients had preoperative computed tomographic scans which revealed no evidence of intracranial hemorrhage and underwent successful corrective cardiac surgery. In the early postoperative period, 4 patients died of cerebral hemorrhage, subarachnoid hemorrhage, or progression of cerebral edema. Two of the 3 surviving patients showed no aggravation of cerebral infarcts postoperatively. In the remaining surviving patient, intracerebral mycotic aneurysms were resolved spontaneously after postoperative antibiotic therapy, although new cerebral hemorrhage, a complication of emboli, occurred after open heart surgery. The results of this study indicated that 1) cerebrovascular complications were the causes of the 4 deaths in this series, and 2) although heparinization during open heart surgery may result in intracerebral hemorrhage from mycotic aneurysm or infarction, early surgical intervention after recent cardiogenic embolic strokes may save patients with minor cerebral infarcts.

Adolescent↗
PubMed1992

[A case report of spinal epidural hematoma complicated after open heart surgery].

The authors reported the first case of acute spinal epidural hematoma (SEH) developed after open heart surgery. The patient was noticed that her legs felt weak and numb on the first postoperative day evening. On the next day morning, neurological examination revealed that flaccid paralysis of both legs and also loss of all sensory perception below the level of Th-6 spine bilaterally. The prolonged effect of anesthesia and painless onset made delayed recognition of the lesion. SEH (Th5-7) was diagnosed with MRI and decompressive surgery was immediately done, sixty hours after the beginning of cardiac operation. But in this case neurological deficits were not changed. We concluded that a routine diagnostic approach was very important procedure to find out this serious complication for all patients underwent open heart surgery in early period of its onset.

Cardiac Surgical Procedures↗
PubMed1992

[Mitral valve surgery for patients after undergoing percutaneous transvenous mitral commissurotomy (PTMC)--investigation on indication of PTMC based on the intraoperative findings].

Ten patients underwent open heart surgery for mitral valve after PTMC because of post PTMC MS (n = 4) and MR (n = 6) out of 150 patients undergoing PTMC in our hospital between June 1987 and October 1991. Intraoperative findings of 4 patients with residual mitral stenosis included severe thickening, stiffening and calcification on anterior and posterior leaflets, commissures and subvalvular apparatus. Mitral valve repair was possible in 2 and mitral valve replacement (MVR) was necessary in the other 2. In all 6 cases who massive mitral regurgitation after PTMC, in repairable tears in the mitral leaflets necessitated MVR. Since in these cases changes in the leaflets were less severe than those of the commissures or subvalvular apparatus, surgical repair could have been possible if open mitral commissurotomy (OMC) was done primarily. Patients selection for PTMC versus OMC based on precise morphological evaluation of mitral valve would reduce occurrence of massive MR resulting in surgical replacement.

Adult↗