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Biomedical subjects

K Seo

Publications and source records attributed to K Seo.

At least 55 records · Page 3Linked to original sources
PubMed1997

Ventricular hypertrophy as a risk factor in ventricular septation for double-inlet left ventricle.

BACKGROUND: Ventricular septation is an option for surgical correlation of double-inlet or common-inlet left ventricle. However, the surgical risk factors of ventricular septation remain unknown. METHODS: Twenty-three patients with double-inlet or common-inlet left ventricle underwent ventricular septation. Preoperative data were compared between the survivors (n = 18) and the nonsurvivors (n = 5) to assess surgical risk factors. RESULTS: There were two early deaths (9.5%) and three late deaths (14.3%). Nonsurvivors of ventricular septation were significantly older at the time of operation (14.0 +/- 6.0 versus 7.0 +/- 5.4 years; p < 0.05) and had greater left ventricular mass (383% +/- 100% versus 206% +/- 57% of normal predicted value; p < 0.005) and greater left ventricular mass to left ventricular end-diastolic volume ratio (1.84% +/- 1.18% versus 0.77% +/- 0.17%/% of normal predicted value; p < 0.005). Univariate logistic regression analysis also revealed age at operation (p < 0.05) and mass/end-diastolic volume ratio (p < 0.05) as significant risk factors for death after operation. Multivariate regression analysis revealed that age at operation positively influenced increased mass/end-diastolic volume ratio (p < 0.001). These findings indicated that ventricular hypertrophy was one of the risk factors for ventricular septation, which had a tendency to progress with age. CONCLUSIONS: Early operation before progression of ventricular hypertrophy is recommended in patients with double-inlet or common-inlet left ventricle who have suitable anatomy for the ventricular septation procedure.

Adolescent↗
PubMed1997

An automatic flow controller for a centrifugal blood pump.

To regulate the perfusion flow rate of a centrifugal blood pump, a microcomputer controller was developed. The computer monitored the flow rate of the pump with an electromagnetic flowmeter or an ultrasonic pulse Doppler flowmeter, rotational speed of the pump, aortic pressure, and the amount of blood in a reservoir. A discrete integral controller with a control interval of 1 s was adopted for the controller. For the safety of the control system, we added functions for detecting a clamp on the tubing, a dislocation of the flow sensor, or an inverse direction of the flow sensor. During a standby period, the computer calculated the rotational speed from aortic pressure to minimize the forward or the backward flow at the start of the pump perfusion. The automatic flow controller was used on 5 patients during cardiac operations and maintained the flow rate within +/-6% of the set point.

Algorithms↗
PubMed1997

[Assessment of myocardial perfusion hemodynamics using echo planar MR imaging].

It was possible to obtain images for individual heart beats using single-shot Echo Planar Imaging(EPI), and changes of myocardial signal intensity could be assessed visually after GD-DTPA administration. Measurement of the same site in the myocardium on myocardial perfusion images for individual heart beats was facilitated by imaging during breath-holding, and accurate evaluation was possible. In patients with coronary artery disease, the site of myocardial infarction tended to show less increase in signal intensity than the normal myocardium, and could easily be distinguished from normal myocardium according to the change in signal intensity. In patients with atrial fibrillation, the signal intensity of the myocardium varied with each heart beat, and it was difficult to assess perfusion hemodynamics. Myocardial perfusion studies using EPI still present problems with respect to spatial resolution, but the myocardial perfusion hemodynamics for individual heart beats can be determined by preparing time/intensity curves. It is also possible to obtain information on cardiac morphology, wall motion, and myocardial metabolism in addition to perfusion data by combining myocardial perfusion studies with methods such as high speed cine MRI, tagging, or myocardial MRS. It is possible that this method will also be useful in studying myocardial viability.

Coronary Circulation↗
PubMed1997

The effect of interleukin-1alpha on outflow facility in rat eyes.

PURPOSE: The authors investigated whether regulation of the trabecular extracellular matrix turnover rate and remodeling plays an important role in decreasing outflow resistance by determining the effect of intracamerally given interleukin-1alpha, a known stimulator of the expression of trabecular matrix metalloproteinases, on outflow facility of albino rat eyes. MATERIALS AND METHODS: Forty normal albino rats (Sprague-Dawley), weighing 250 to 300 g, were studied. Rats were anesthetized by intraperitoneal pentobarbital sodium (30 mg/kg) injection. The rats were separated into four groups and given 5, 10, 25, or 50 units of interleukin-1alpha injected intracamerally in one eye. Bovine serum albumin in phosphate-buffered saline, which was used to dissolve the interleukin-1alpha, was injected in the fellow eye as a control. Outflow facility was measured by two-level constant pressure perfusion 1, 3, and 7 days after injection. RESULTS: The eyes treated with 50 units of interleukin-1alpha showed a statistically significant increase of outflow facility by 37% compared with the contralateral control eyes 3 days after injection, but returned to normal levels in 7 days. The eyes treated with 5, 10, 25, or 50 units of interleukin-1alpha showed outflow facility increases of 12%, 20%, 39%, and 37%, respectively, 3 days after injection. CONCLUSION: Interleukin-1alpha increased the outflow facility, supporting the hypothesis that regulation of trabecular meshwork extracellular matrix plays a role in trabecular outflow resistance.

Animals↗
PubMed1997

[Femoral to radial artery pressure gradient in the patients undergoing coronary artery bypass graft under normothermic cardiopulmonary bypass].

Femoral to radial artery pressure gradient was evaluated in 14 patients undergoing coronary artery bypass graft under normothermic cardiopulmonary bypass (CPB). CPB was instituted at a flow rate of 2.6 l.min-1.m-2, using non-pulsatile pump and blood temperature of pump arterial line was controlled to maintain bladder temperature between 36 and 37 degrees C. Pressure gradients occurred 30 min after commencement of CPB and the mean gradients of systolic, diastolic and mean artery pressure were maximum all at the end of CPB (38 +/- 7 mmHg, 4 +/- 1 mmHg and 10 +/- 2 mmHg). These pressure gradients remained until the end of the surgery. Throughout the operation, nasopharyngeal and blood temperature remained unchanged, while mean palm temperature increased from 31.8 degrees C (after induction) to 34.6 degrees C (30 min after commencement of CPB) and thereafter remained between 33.3 and 33.9 degrees C. This increase in peripheral temperature might indicate that normothermic CPB was accompanied by peripheral vasodilatation. These results indicate that the magnitude of femoral to radial pressure gradient during normothermic CPB is similar to that during mild hypothermic CPB.

Aged↗
PubMed1997

[Surgical relief of airway obstruction from a double aortic arch associated with corrected transposition of the great arteries, pulmonary atresia and bilateral patent ductus arteriosus in a neonate].

A rare 20-day-old male with double aortic arch, corrected transposition of the great arteries (cTGA), pulmonary atresia and bilateral patent ductus arteriosus (PDA) was transported to our institute because of severe respiratory dysfunction and cyanosis. The patient had been already intubated and ventilated on respirator. A echocardiography and cine-angiography demonstrated that the both sides aortic arch had almost identical sizes, originating common carotid arteries and subclavian arteries and PDAs respectively, and the descending aorta located on the left side of the mid-line. At the first surgery, the distal of the right aortic arch was divided just proximal to the descending aorta after complete tissue dissection around the arch. The divided right sided aortic arch was mobilized from posterior to anterior aspect of the bronchus. Then the right subclavian artery was divided and an original Blalock-Taussig shunt was employed. The right sided PDA was ligated. After the first surgery, respiratory dysfunction lasted for weeks mainly because of the PGE1 dependent left sided PDA. At the second surgery, left sided modified Blalock-Taussig shunt was constructed and the left sided PDA was divided. These procedures resulted in stable respiratory status and oxygen saturation. The patient was extubated three days later and now in satisfactory clinical condition.

Abnormalities, Multiple↗
PubMed1997

[Surgical treatment of double outlet left ventricle].

Double outlet left ventricle (DOLV) is an uncommon congenital cardiac defect which was first reported by Sakakibara and associates. We studied anatomical aspects relevant to surgical repair in our 4 cases and additional 28 cases which had been reported on the literatures. The locations of ventricular septal defect (VSD) were subaortic in 20 cases, subpulmonary in 7, doubly-committed in 2 and unknown in 2. The positions of the aorta relative to the pulmonary artery were right or left anterior oblique in 11 cases, right or left side-by-side in 9, right or left posterior oblique in 10 and unknown in 3. The definitive surgery included Rastelli type operation in 18 cases, right ventricular outflow tract repair with closure of VSD in 6, intraventricular conduit repair in 4 and Fontan type operation in 4. In regard to the selection of the procedure, the size of right ventricle, the presence of pulmonary stenosis, the location of VSD and the relationship of the great arteries are very important. Although most of the patients underwent the Rastelli type operation, the right ventricular outflow tract reconstruction or intraventricular conduit repair could be adopted particularly in patients with posterior oblique position of the aorta relative to the pulmonary artery or subpulmonary VSD.

Adolescent↗
PubMed1996

Electromagnetic interference of an external temporary pacemaker during maxillofacial and neck surgery.

Indirect inhibition of an external temporary pacemaker by electrocautery is reported. Before induction of general anesthesia for a hemimaxillectomy and radical neck dissection, a temporary transvenous demand pacemaker was inserted into a patient with a first-degree atrioventricular block and complete left bundle-branch block. Although we provided common precautions to prevent electromagnetic interference by electrocautery, pacing failure still occurred. It was thought to be caused by current dispersing from the active electrocautery electrode. This case suggests that occipital placement of the electrocautery ground plate should be considered during neck surgery in a patient requiring a temporary pacemaker.

Aged↗
PubMed1996

[The effect of intraportal chemotherapy in terms of administered dose of 5-FU].

Forty-six patients with colorectal cancer were studied for the effects of intraportal chemotherapy in terms of the administered dose of 5-FU. No liver metastases occurred in patients with a total dose of more than 4 g of 5-FU. The five-year survival rate for patients with a total dose of more than 4 g of 5-FU was 98%, which was better than that for control (72%). In patients administered 500 approximately 600 mg/body/day of 5-FU, the concentration of 5-FU in the peripheral blood was 0.022 approximately 0.027 microgram/ml. Liver dysfunction occurred in 22%, 33%, and 80% of patients administered less than 4 g, 4 approximately 4.9 g, or more than 5 g of 5-FU, respectively, but almost all of them were grade 1. These results suggest that intraportal chemotherapy administered with a total of more than 4 g of 5-FU was effective for prevention of liver metastases after resection of colorectal cancer.

Colorectal Neoplasms↗
PubMed1996

[A case of recurrent squamous cell carcinoma of cervix successfully treated with BOMP].

Combination chemotherapy consisting of bleomycin, vincristine, mitomycin C and cisplatin (BOMP) was applied to a case (57 years old) with recurrence of squamous cell carcinoma of the cervix. The patient with FIGO stage IIIb cervical carcinoma had been treated with radiotherapy seven years ago. She was affected by malignant pericardial effusion, and was treated with direct intrapericardial administration of cisplatin (20 mg). After instillation, ultrasonography and computed tomography showed the wall thickening of colon and marked ascites. Barium enema showed the circumferential narrowing and serrations of colon, and it was diagnosed to be carcinomatous peritonitis. She was treated with BOMP consisting of BLM (5 mg, i.m., days 1 - 5), VCR (1 mg, i.v., day 5'), MMC (8 mg, i.v., day 5), and CDDP (70 mg, d.i.v., day 5). After three courses of BOMP therapy, she achieved a complete response with few toxic effects and did not require special care. She has been free of disease for six months and her performance status is 0. This encouraging result warrants the use of this combination chemotherapy regimen in other patients with recurrent squamous cell carcinoma of the cervix.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1995

[Reconstruction of pulmonary trunk in pulmonary atresia and tetralogy of Fallot utilizing autologous tissue].

Establishment of right ventricular-pulmonary arterial continuity with autologous tissue, avoiding the use of prosthetic conduit, is presented. From February 1992 through March 1993, 22 patients with pulmonary atresia and tetralogy of Fallot underwent reparative operation at The Heart institute of Japan. In 20 patients out of the 22 patients, the right ventricular-pulmonary arterial continuity was successfully established with either direct anastomosis or insertion of tailored autologous pericardial tube. The morphology of the right ventricular-pulmonary arterial discontinuity comprised of valvular and infundibular atresia in seven, truncal atresia in nine, and failed extracardiac conduit in four. In patients with relatively short distance between right ventricle and pulmonary artery, the pulmonary artery was retracted and anastomosed directly to the cranial margin of the ventriculotomy incision to serve as a smooth floor made of autologous tissue. In patients with long distance, tailored autologous pericardial tube was interposed between right ventricle and pulmonary artery instead of using prosthetic conduit. Both techniques were completed by mono- or bicuspid anterior patch made of equine pericardial conduit. There were no early and late deaths. Postoperative catheterization data showed satisfactory reduction of right ventricular pressure with the right-to-left ventricular systolic pressure ratio ranging from 0.42 to 0.69 (average 0.52) in direct anastomosis group and 0.43 to 0.48 (average 0.45) in autologous pericardial tube group, and the pressure gradient across right ventricular outflow tract ranged from 1 to 15 (average 8) mmHg and 1 to 15 (average 5.8), respectively. The distributing frequency of late complication, mainly conduit obstruction, of prosthetic materials prompted us to use autologous tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

[Pharmacokinetic study in biochemical modulation therapy of UFT with leucovorin tablet].

Preoperative oral treatment with UFT and leucovorin tablet was performed. Pharmacokinetics, degree of degeneration in the tumor tissue and side effects were studied in 34 patients with colorectal cancer preoperatively given 400 mg/day of UFT with 20 mg/day of leucovorin tablet or 400 mg/day of UFT alone. Results were as follows; 1) there was no significant difference between UFTL group and UFT group regarding concentration of FdUMP in the tumor tissue. In UFTL group, concentration of FdUMP was higher in the tumor tissue of moderately differentiated adenocarcinoma than that of well differentiated adenocarcinoma. No significant differences regarding concentration of FdUMP were obtained between diploid and aneuploid groups. 2) TS inhibition rate in the tumor tissue was 66.8% in UFTL group and 53.2% in UFT group, and there was a significant difference between these two groups. TS inhibition rate in the tumor tissue was higher than that in the normal tissue either in UFTL group or UFT group. However, there were no significant differences of TS inhibition rates regarding differentiation of tumor tissue or DNA ploidy pattern. 3) Degree of degeneration of more than Grade 2 was not obtained in any patients of either UFTL or UFT group. 4) There was no change in blood laboratory data between before and after medication. Only one patient complained Grade 1 pruritus in UFTL group. These results suggest that oral biochemical modulation therapy of UFT with leucovorin tablet is effective because of pharmacokinetically high anti-tumor effect and minimal side effects.

Adenocarcinoma↗
PubMed1995

[Surgical treatment of transposition of the great arteries with intact ventricular septum associated with left ventricular outflow obstruction].

Thirteen patients have undergone surgical treatment for transposition of the great arteries (TGA) with intact ventricular septum (IVS) associated with left ventricular outflow obstruction (LVOTO) in our institute. Ages at operation ranged from three months to six years (mean 9.2 +/- 4.7 months). Of these patients, seven had dynamic type LVOTO (group I), and six had organic LVOTO (group II). Preoperative left ventricular end-diastolic volume was significantly smaller in group II (78 +/- 13% of normal) than control group (135 +/- 53% of normal). Preoperative pressure gradient between the pulmonary artery and left ventricle was significantly greater in group II (55.8 +/- 3.2 mmHg) than group I (35.2 +/- 3.9 mmHg). In group I, II patients underwent two-stage ASO, the other 5 patients underwent Senning operation. The reason for the Senning operation were era before introduction of ASO in our institute (1983) or unsuccessful training of the left ventricle. In group II, all but one patient underwent Senning operation, the other underwent a successful Fontan operation with Damus anastomosis because of too small left ventricle (LVEDV: 49% of normal). Techniques to correct LVOTO at the definitive operation included ventriculotomy (n = 4) and pulmonary valvotomy (n = 2). One patients in group II underwent a Fontan operation with Damus anastomosis due to an underdeveloped left ventricle (LVEDV: 49% of normal). There was no early or late death. The postoperative pressure gradients disappeared or reduced to trivial levels in all patients. At present no LVOTO has developed in any of the patients.

Cardiac Surgical Procedures↗
PubMed1995

[Three-dimensional longitudinal dissection view of hollow viscus].

To visualize the pathologies of hollow viscus and their extension three-dimensionally, volume data of the larynx, trachea, stomach, rectum, and urinary bladder were obtained using helical CT with moderately thin slices. Longitudinal cut sections were made as in a simulated surgical cut, and the interior morphology was displayed along with the pathology. A cylindrical projection profile was made by making a longitudinal incision on one wall and pulling apart the flaps to reveal the interior, providing better visual perception. The detailed outline from the 3D profile and the cylindrical projection views constituted an added advantage over the existing procedures.

Humans↗
PubMed1994

Ectopic gastric mucosa in the upper esophagus: detection and radiographic findings.

PURPOSE: To detect and characterize the appearance of islands of ectopic gastric mucosa in the upper esophagus at routine examination of the upper gastrointestinal (GI) tract. MATERIALS AND METHODS: Well-distended upper esophagus was documented with spot radiographs obtained with routine double-contrast examination performed after administration of high-density barium in nine patients. Detected lesions were confirmed by means of endoscopy and biopsy. RESULTS: Twelve lesions were detected. Radiographic findings were characterized by either a discrete, shallow depression surrounded by a subtle, rimlike elevation on double-contrast images or by a pair of small indentations on the same wall on full-column, single-contrast images at the level of the thoracic inlet. Endoscopic examination revealed well-circumscribed areas of reddish mucosa located 15-26 cm from the incisors. CONCLUSION: Ectopic gastric mucosa in the upper esophagus is easily demonstrated at routine examination of the upper GI tract. Diagnosis can be based on location and characteristic radiographic appearance.

Adult↗
PubMed1994

[Pharmacokinetic and clinical evaluation of cefozopran in the pediatric field].

We conducted pharmacokinetic and clinical studies on cefozopran (CZOP, SCE-2787), an aminothiadiazolmethoxyiminoacetamido cephalosporin, and obtained the following results. 1. Concentrations in serum/excretion in urine We studied pharmacokinetic in children upon intravenous bolus injection and 30-minute intravenous drip infusion in single doses of 10 and 20 mg/kg. Upon intravenous bolus injection, mean serum concentrations 30 minutes after administration of 10 and 20 mg/kg were 27.8 and 52.3 micrograms/ml, respectively, and half-lives were 2.01 and 2.02 hours, respectively. Upon 30-minute intravenous drip infusion, mean serum concentrations on completion of the drip infusions of 10 and 20 mg/kg were 36.8 and 70.3 micrograms/ml, respectively, and half-lives were 1.74 and 4.11 hours, respectively. Their urinary recovery rates in the first 8 hours after administration were higher than 67.0% in the former regimen and between 23.2 to 98.0% in the latter. 2. Clinical results 54 patients were treated with CZOP for 32 cases of pneumonia, 11 cases of bronchitis, 3 cases of cervical lymphadenitis, 1 case of purulent tonsillitis, 2 cases of phlegmon, 2 cases of enterogastritis and 3 cases of urinary tract infections. CZOP gave "excellent" or "good" responses in 53 cases. 1 case of urinary tract infection showed fair response. Diarrhea was observed in 1 case. Abnormal laboratory test results were noted in 9 patients including elevations of eosinophils, GOT and GPT. In no cases the treatment had to be discontinued.

Adolescent↗
PubMed1994

[Pharmacokinetic studies on continuous intraportal 5-fluorouracil infusion].

Pharmacokinetics of 5-FU administered by continuous intraportal infusion were studied by infusing 5 mg/kg, 10 mg/kg, 20 mg/kg, and 40 mg/kg of 5-FU, respectively, into the ileocecal vein for an hour. Blood samples were collected from portal vein, femoral vein and liver, and small intestine specimens were obtained at proper intervals. The rabbits were sacrificed at 120 minutes from the start of 5-FU infusion. The results were as follows: Extremely high concentrations of 5-FU in the portal vein, femoral vein and liver tissue were observed in the 5-FU group infused with 40 mg/kg. This phenomenon was suggested to rely on the effect by which the 5-FU catabolic enzyme, dihydrouracil dehydrogenase, was saturated with a large inflow of 5-FU. FdUMP concentration of the liver was lower than that of the small intestine in all groups. These results suggest that a large dose of 5-FU infusion is effective to increase the FdUMP concentration in the liver with continuous intraportal 5-FU infusion.

Animals↗