Biomedical subjects

H Tsuboi

Publications and source records attributed to H Tsuboi.

At least 109 records · Page 6Linked to original sources

PubMed1991

Evaluation of a new calcium containing cardioplegic solution in the isolated rabbit heart in comparison to a calcium-free, low sodium solution.

Isolated perfused rabbit hearts were studied to compare the effects of 3 hour ischemic arrest following either calcium-free or calcium-containing cardioplegia, on the recovery of isovolumic function of the left ventricle, coronary flow, release of creatine phosphokinase and myocardial water content. The hearts perfused with the calcium-containing solution (Ca 0.5 mmol/L) showed better recovery of the developed pressure in the left ventricle, and its first derivative and compliance. Coronary flow at a constant perfusion pressure was better restored during reperfusion in the hearts with calcium-containing solution. The release of less CPK and a lower water content were also observed in the hearts reperfused with calcium-containing solution. We concluded that calcium-containing cardioplegic solution with a high concentration of magnesium (10 mmol/L) was superior to calcium-free solution for myocardial protection.

Animals↗

PubMed1991

Peripheral vascular permeability following a thermal injury to the airway.

Effects of thermal injury to the airway on the vascular permeability in the region of head and neck, were studied in the canine models. The thermal airway injury was produced by an inhalation of a gas burner's flame through the metallic tracheostomy cannula. The changes in vascular permeability were evaluated by calculating the reflection coefficient, which was obtained by the protein washdown technique into lymph. The reflection coefficient after the flame inhalation did not show any increases, while it increased significantly after a histamine infusion into the carotic artery. We concluded, that the vascular permeability in the unburned area does not increase at least in the first 3 hr after a thermal injury to the airway.

Journal Article↗

PubMed1991

Quantitative estimation of infarct size by simultaneous dual radionuclide single photon emission computed tomography: comparison with peak serum creatine kinase activity.

To test the hypothesis that simultaneous dual energy single photon emission computed tomography (SPECT) with technetium-99m (99mTc) pyrophosphate and thallium-201 (201TI) can provide an accurate estimate of the size of myocardial infarction and to assess the correlation between infarct size and peak serum creatine kinase activity, 165 patients with acute myocardial infarction underwent SPECT 3.2 +/- 1.3 (SD) days after the onset of acute myocardial infarction. In the present study, the difference in the intensity of 99mTc-pyrophosphate accumulation was assumed to be attributable to difference in the volume of infarcted myocardium, and the infarct volume was corrected by the ratio of the myocardial activity to the osseous activity to quantify the intensity of 99mTc-pyrophosphate accumulation. The correlation of measured infarct volume with peak serum creatine kinase activity was significant (r = 0.60, p less than 0.01). There was also a significant linear correlation between the corrected infarct volume and peak serum creatine kinase activity (r = 0.71, p less than 0.01). Subgroup analysis showed a high correlation between corrected volume and peak creatine kinase activity in patients with anterior infarctions (r = 0.75, p less than 0.01) but a poor correlation in patients with inferior or posterior infarctions (r = 0.50, p less than 0.01). In both the early reperfusion and the no reperfusion groups, a good correlation was found between corrected infarct volume and peak serum creatine kinase activity (r = 0.76 and r = 0.76, respectively; p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical Enzyme Tests↗

PubMed1991

Growth of tracheal anastomoses: advantage of absorbable interrupted sutures.

Growth of the trachea after complete transection and anastomosis was studied in four groups of 1-month-old New Zealand white rabbits. The trachea was transected at the fifth cartilaginous ring and then anastomosed with continuous 6-0 polypropylene (Prolene) (group 1), interrupted 6-0 polypropylene (group 2), continuous 6-0 polydioxanone (PDS) (group 3), or interrupted 6-0 PDS (group 4). The animals were followed up for 90 to 103 days (mean follow-up, 95 days). At the time the animals were killed, body weight had increased 125% (1.2 to 2.7 +/- 0.18 kg). Growth of the trachea was assessed at the time of death. Results from this study suggest that growth of a tracheal anastomosis is retarded in a growing animal model. The degree of resultant stenosis was significantly less when an absorbable suture material (PDS) and an interrupted suturing technique were used.

Anastomosis, Surgical↗

PubMed1991

Immunomodulator, LZ-8, prevents antibody production in mice.

LZ-8, a new and recently discovered immunomodulator from Ganoderma lucidum, has been shown to have immunosuppressive activity in vivo and to be a member of the immunoglobulin superfamily. In this paper we examined the in vivo effect of LZ-8 on antibody production using the hepatitis B surface antigen (HBs Ag) in mice. LZ-8 had mitogenic activity in vitro towards spleen cells of C57BL/10 (B10) and C57BL/10BR (B10BR) as previously shown towards those of DBA/2 mice. B10 and B10BR mice produced anti-HBs Ag antibody by the twice sensitization of the antigen while intraperitoneal administration of LZ-8 twice weekly into the mice (8 and 12 mg/kg) greatly prevented the production of antibody to HBs Ag (83.3-96.8% inhibition). We further examined the effect of LZ-8 administration on mitogen responsibility of spleen cells and on the T-cell subset population in both the spleen and lymph node but no significant differences were observed between the LZ-8 treated and untreated mice. These results suggest that the immunosuppressive activities of LZ-8, previously shown, such as the prevention of systemic anaphylaxis and the Arthus reactions, were caused by the blocking of antigen-specific antibody production.

Adjuvants, Immunologic↗

PubMed1991

Clinical study of the stunned myocardium.

Clinical features of 37 cases of stunned myocardium were studied. Mean duration of asynergy was 22.6 +/- 15.7 days. In all 11 cases of unstable angina without any significant serum creatine kinase leakage, the duration of asynergy was within 14 days. Related coronary lesions were reperfused (spontaneously or by interventional therapy) to TIMI grade II or higher. Transient Q waves were observed in 39% of all cases. Negative T waves tended to be prolonged, and persisted after disappearance of asynergy in 74% of all cases. 201Tl uptake in the stunned area varied widely between individual cases (ranging from "absent" to "normal"), although it became normal in all cases in the chronic stage. Mal-distribution of 99mTc-pyrophosphate (PYP) to the endocardial side of the stunned area was observed in 33%. In 186 cases of acute coronary syndrome, we studied whether or not reversibility of ischemia-disturbed myocardium could be predicted by simultaneous dual isotope SPECT, and found that 201Tl-uptake in the chronic stage significantly improved in the region showing absence of 99mTc-PYP accumulation or maldistribution of 99mTc-PYP to the endocardial side, while reversibility of the region showing transmural 99mTc-PYP accumulation and a dought pattern was poor. Ischemia-associated myocardial damage recovered to various degrees, and dual isotope SPECT was useful in evaluating the reversibility of such damage already at the acute stage.

Adult↗

PubMed1991

[Chylothorax developed after cardiac surgery in children: a report of three cases].

Two children developed chylothorax after median sternotomy and a third child developed chylothorax after a Blalock-Taussig operation under the left thoracotomy. The first patient had a closure of ASD and a pulmonary valvotomy and then later developed chylothorax. The thoracic duct was ligated 10 cm just above the diaphragm at 28 days after the first operation because of unsuccessful conservative treatment. The second patient had a Blalock-Taussig operation and the third patient had radical operation for ECD and both developed chylothorax. The latter two patients were cured with conservative treatments such as the administration of Medium Chain Triglyceride or total parenteral nutrition with thoracic drainage. Children who developed chylothorax after cardiac surgery should be treated conservatively for at least the early postoperative period when circulatory and/or respiratory conditions are still unstable.

Child, Preschool↗

PubMed1991

Concentration of Mn-superoxide dismutase in serum in acute myocardial infarction.

Serum concentrations of manganese-containing superoxide dismutase (Mn-SOD; EC 1.15.1.1), a mitochondrial enzyme present in high concentrations in the heart, were measured successively by enzyme immunoassay in 18 patients with acute myocardial infarction (AMI) and in eight with angina pectoris. Results were compared with creatine kinase (EC 2.7.3.2) isoenzyme MB (CK-MB) concentrations in the same specimens. The mean (and SD) serum Mn-SOD concentration in 120 healthy adults was 77.5 (18) micrograms/L. Mn-SOD concentrations exceeding 150 micrograms/L (greater than mean + 4 SD) were considered above-normal. In patients with AMI, the Mn-SOD concentration was 80 (16.8) micrograms/L on admission and increased gradually after the first hospital day. The peak, 260 (109) microgram/L, occurred on the fourth hospital day, at which time the Mn-SOD concentrations in all AMI patients were above normal. Thereafter the Mn-SOD concentration decreased slowly, but still was above normal in 14 of 18 patients on the seventh hospital day. On the other hand, in patients with angina pectoris, the Mn-SOD concentration was 78 (11) micrograms/L on admission and did not increase significantly [peak value 97.5 (42) micrograms/L on the fourth hospital day]. The serum concentration of Mn-SOD is a potentially useful marker for estimating cardiac mitochondrial damage and for diagnosing AMI, especially in the late phase.

Adult↗

PubMed1991

[Centrifugal pump as right ventricular assist pump in the treatment of right ventricular failure following resection of left atrial myxoma].

A 31-year-old woman had a left atrial myxoma associated with severe pulmonary hypertension and respiratory failure because of incarceration of the tumor to the mitral valve. Emergency surgery was performed, but the patient could not be weaned from cardiopulmonary bypass because of right ventricular failure. A Biomedicus centrifugal pump was used as a right ventricular assist pump. The result was a successful termination of cardiopulmonary bypass. With the support of an intra-aortic balloon pump, the right ventricular assist pump was removed 38 hours after the operation, and the intra-aortic balloon pump was terminated 2 days later. The centrifugal pump is very useful at the majority of centers where the pneumatically activated bi-valved ventricular assist device is unavailable. The Biomedicus centrifugal pump can be easily applied for treatment of perioperative right ventricular failure and is very useful for short-term use without systemic anticoagulants.

Adult↗

PubMed1990

Clinical trial of nicardipine cardioplegia in pediatric cardiac surgery.

To clarify the effectiveness of nicardipine, one of the dihydropyridine calcium-channel blockers, for myocardial protection during cold potassium cardioplegic arrest in pediatric cardiac surgery, a clinical trial of nicardipine (0.25 mg/L) added to potassium cardioplegic solution was performed in children undergoing surgical repair of congenital heart diseases. Twenty patients were selected to receive nicardipine cardioplegia and 13 patients received a standard potassium cardioplegia, serving as a control group. Nicardipine cardioplegia provided better cardiac performance in the early postoperative period and reduced release of the MB isozyme of creatine kinase, as determined during a 48-hour postoperative period. These results suggest that nicardipine added to cold potassium cardioplegic solution offers additional protection for the myocardium during ischemia and postischemic reperfusion in pediatric cardiac surgery.

Blood Pressure↗

PubMed1990

[Characterization of the asynergic myocardium in acute coronary syndrome using simultaneous dual radionuclide emission computed tomography].

The purpose of the present study was to evaluate the tissue characterization of the ischemic myocardium by dual single photon emission computed tomography (SPECT) with thallium-201 (Tl-201) and technetium-99m pyrophosphate (Tc-99m PYP) using the simultaneous collection method. The subjects consisted of 84 patients with acute coronary syndrome followed by protracted left ventricular asynergy. For precise interpretation of clinical scintigraphy, we used phantom experiments and the results were as follows: 1. The residual myocardium in the infarcted area could be evaluated to some extent from the severity of the defect on Tl-201 SPECT with optimal and unified image processing standardized by maximal pixel counts in the myocardium. 2. The influence of cross talk between two radionuclides on each tomographic image was negligible under usual clinical conditions. 3. In a subendocardial infarction model where the Tc-99m layer was located within 50% inside the phantom wall and the other space was filled with 201TlCl solution, the Tc-99m layer was clearly visualized inwardly as compared with the Tl-201 layer on dual SPECT with optimal image processing. 4. Transmural infarction could be visualized as a total defect on Tl-201 SPECT only when its diameter was greater than 2 to 2.5 cm. Taking these results into account, we evaluated clinical cases. According to the peak CK value and Tl-201 SPECT in the chronic phase, the subjects were categorized as transmural infarction (TMI), nontransmural infarction (NTMI) and unstable angina pectoris (UAP), and the scintigraphic characteristics of each group were compared. Short-axis tomographic features of all lesions were classified in nine types from 1A to IIIC by the combination of Tl-201 uptake grades (total defect: I, reduced uptake: II, normal: III) and the condition of Tc-99m PYP accumulation (negative: A, transmural: B, subendocardial: C). The relationship between recovery from asynergy and the dual scintigraphic findings was also evaluated and 17 patients in whom asynergy had nearly resolved in the chronic phase was especially classified in a reversible ischemic myocardial damage (RIMD) group. The clinical results were as follows: 1. In cases without reinfarction, a Tl-201 uptake in ischemically-injured lesions was variably improved in the chronic phase. In 9% of all the lesions of NTMI, a Tl-201 uptake showed total defects in the acute phase. 2. Type IIC lesions were most frequently observed, accounting for 43% of all lesions of NTMI.(ABSTRACT TRUNCATED AT 400 WORDS)

Aged↗

PubMed1990

[Three operated cases of LMT-lesion with chief complaint of syncopal attack].

An urgent aorto-coronary bypass operation (AC-bypass) was made in three patients with unstable angina pectoris, suffering from stenosis of the left main trunk (LMT). All patients were admitted with chief complaints of chest discomfort and syncopal attack. Case 1 was a 71 year-old man who suffered with chest discomfort and syncopal attack. He was admitted to our emergency room by ambulance 40 minutes after the syncopal attack, on January 11, 1989. His blood pressure was 140/96; pulse 84 and regular. The electrocardiogram (ECG) showed right bundle branch block, ST elevation in aVR, aVL and ST depression in all other leads. Coronary arteriogram (CAG) was made urgently and showed 80% stenosis in LMT. The emergency AC-bypass operation was successfully carried out about 3 hours and 10 minutes after the onset of symptoms. Case 2 was a 51 year-old man who suffered from precordial oppression and syncopal attack. He was admitted to our emergency room by ambulance about 1 hour after the attack, on January 17, 1989. His blood pressure was 94/74; pulse 120 and irregular. Chest radiography showed a cardiothoracic ratio of 58% and the ECG disclosed atrial fibrillation, ST elevation in aVR and ST depression in I, II, III, aVF, V1-6. The echocardiogram revealed hypokinetic motion in the antero-lateral wall of the left ventricle. CAG was carried out without delay, and showed 70% stenosis with slit in LMT. An emergency AC-bypass operation was successfully carried out about 3 hours and 50 minutes after the onset of symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1990

[A surgical case of aortic regurgitation with Behçet disease].

A case of Behçet disease associated with aortic valve regurgitation treated with aortic valve replacement is reported. The patient was treated successfully with special surgical techniques for prevention of post operative paravalvular leakage and occurrence of pseudo aneurysm because the patient was under long-term steroid therapy for Behçet disease.

Aortic Valve↗

PubMed1990

[Legionellosis].

Although increasing attention is being given to Legionella pneumonia in Japan, reports of solitary onset of this disease are scant in Japan. The patient, from whom L. dumoffii was isolated, was a 59-year-old male with no underlying disease. He visited our hospital because of fever and cough, and was admitted to our department for X-ray findings consistent with pneumonia. After admission, pulmonary lesions spread rapidly, and based on the suspicion of Legionella pneumonia, drugs such as EM, RFP and MINO were used. However, the patient died on the 26th hospital day. L. dumoffii was isolated from specimens obtained by airway aspiration before death and specimens of lung abscess and airway discharge obtained during autopsy (7 specimens in total). In addition, the L. dumoffii antibody titer in the serum became elevated. This is the first case of L. dumoffii pneumonia reported in Japan. The other case was in an 81-year-old male with underlying disease. He was admitted urgently with suspected pneumonia but died on the following day. L. pneumophila serogroup 5 was isolated from autopsied lung tissue. Fatality is high for this disease, making early diagnosis and treatment with appropriate antibiotics essential. Physicians should bear in mind the possibility of this disease and request the necessary laboratory tests in suspected cases without delay.

Aged↗

PubMed1990

[A successful removal of a left atrial massive ball thrombus caused by mitral stenosis].

A 66-year-old female with a mitral stenosis and a left atrial massive ball thrombus is presented. She was admitted due to a transient right hemiplegia and a speech disturbance. This thrombus had been detected preoperatively by an echocardiogram and a left atriography. A mitral valve replacement using a Björk-Shiley valve 27 mm, accompanied with the removal of the thrombus was performed. The ball thrombus was dark red, 55 x 35 x 32 mm in size and 15 g in weight. After the surgery, the patient progressed well. Because of the high frequency of peripheral embolism and of sudden death, a left atrial ball thrombus should be removed immediately.

Female↗

PubMed1990

[Noonan syndrome associated with atrial septal defect, ventricular septal defect and pulmonary stenosis--a case report].

A 10 year old girl with diagnosis of Noonan syndrome was admitted to our hospital because of easy fatiguability and cardiac murmur. She had a peculiar face with hypertelorism, saddle nose, webbed neck and kyphosis. Chromosomal analysis demonstrated normal 46 XX pattern. Associated cardiac anomalies in this case were atrial septal defect, ventricular septal defect and pulmonary stenosis caused by pulmonary valvular dysplasia. The cardiac anomalies were corrected successfully and postoperative clinical course was uneventful.

Child↗

PubMed1990

[Significance of measuring Cu, Zn-superoxide dismutase (SOD) levels in open heart surgery].

Cu, Zn-SOD levels, free hemoglobin (Hb) and CPK-MB were measured in 18 patients undergoing open heart surgery. In order to evaluate the serum level of Cu, Zn-SOD, the ratio of Cu, Zn-SOD/free Hb was used to eliminate an influx of Cu, Zn-SOD released from erythrocytes during cardiopulmonary bypass. The value of Cu, Zn-SOD/free Hb was decreased significantly 30 minutes after aortic declamping and the minimal value was indicated 1 hour after the termination of cardiopulmonary bypass compared with the preoperative status. We thought that the decrease was due to the consumption of SOD competing against free radical generation. The correlation between the minimal value of Cu, Zn-SOD/free Hb and the ischemic time was apparent but the correlation between the minimal value of Cu, Zn-SOD/free Hb and the value of peak CPK-MB was not determined. It was suggested that the serum free radicals were not only derived from the heart but also from the lung or other parts of the body during open heart surgery.

Adult↗

PubMed1990

[Valvuloplasty for acute mitral insufficiency caused by torn chordae (Carpentier method): report of a case].

A 66-year-old female was admitted to our hospital with acute heart failure (NYHA III), and diagnosed as an MR + Tr. The cause of MR was torn chordae of the posterior leaflet of the mitral valve. A prolapse part of the posterior leaflet was resected and sutured by McGoon's method. Valvuloplasty was performed by using a Carpentier ring. Postoperative course was uneventful. She recovered well after the operation. Histological examination of the valve showed myxomatous degeneration.

Aged↗