Biomedical subjects

Y Otani

Publications and source records attributed to Y Otani.

At least 127 records · Page 7Linked to original sources

PubMed1996

Use of ultrasound-guided percutaneous needle biopsy in the diagnosis of mediastinal tumors.

We herein report the usefulness of ultrasound-guided percutaneous needle biopsy for histological diagnosis in 18 patients with mediastinal tumors. Computed tomography revealed these tumors to be in contact with the chest wall. The preoperative diagnosis was thymoma in 7 patients, germinoma in 5, neurogenic tumor in 3, and "other" in 3. The most commonly encountered indication for an ultrasound-guided percutaneous needle biopsy was an anterior mediastinal lesion (78%; 14 of 18 patients). In 16 (89%) of the 18 patients, the biopsy diagnosis corresponded to the postoperative diagnosis. No complications were encountered in any of the patients. This new technique of ultrasound-guided percutaneous needle biopsy is both relatively simple and highly accurate and may thus be useful for outpatients. Preoperative ultrasound-guided percutaneous needle biopsy is thus considered to be a safe and reliable method for the histological diagnosis of mediastinal tumors, and a good alternative to traditional biopsy techniques such as mediastinoscopy or thoracotomy.

Adolescent↗

PubMed1996

Successful treatment of Wolff-Parkinson-White syndrome with concomitant mitral stenosis by simultaneous surgery.

We report the case of a 61-year-old man with type B Wolff-Parkinson-White (WPW) syndrome associated with a right atrioventricular (AV) accessory pathway and concomitant mitral stenosis, who underwent successful operative treatment by simultaneous surgery. His preoperative course had been characterized by cardiac failure and repeated episodes of atrial tachyarrhythmia, in the form of fibrillation and flutter, which were difficult to control by conventional medication. Preoperative electrocardiograms (ECGs) had suggested that the accessory pathway was located in the right posterior to posteroseptal wall; however, at the time of surgery, epicardial electrophysiological mapping with sock electrodes revealed a preexcitation area in the AV groove at the lateral right margin of the heart. This discrepancy was thought to have been due to the presence of mitral stenosis or multiple accessory pathways. Thus, division and cryoablation of the accessory pathway by an endocardial approach, in addition to mitral valve replacement, were performed under cardiopulmonary bypass. His postoperative course was uneventful, and subsequent ECGs revealed that the delta waves had disappeared. The successful outcome of this patient demonstrates the effectiveness of simultaneous surgery for WPW syndrome associated with valvular disease.

Atrial Fibrillation↗

PubMed1996

Serial growth of human malignant fibrous histiocytoma xenografts in immunodeficient mice.

Malignant fibrous histiocytoma (MFH) is on of the most common soft tissue sarcomas of adulthood, the only treatment for which involves surgical resection of the extremities and retroperitoneum, while no standard postoperative adjuvant chemotherapy has been established. We report herein on the establishment of a serially transplantable MFH strain in immunodeficient mice. An intraperitoneal tumor was resected from a patient with multiple recurrent MFH, inoculated into the subcutaneous tissue of mice with severe combined immunodeficiency (SCID), and established as a serially transplantable MFH strain, MH-1. The chemosensitivity of MH-1 was similar to that of the original fresh surgical specimen, as confirmed by the 3-(4,5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) test. We believe that this serially transplantable strain will be useful for further studies on chemotherapy effective against MFH.

Abdominal Neoplasms↗

PubMed1996

A malignant Triton tumor in the anterior mediastinum requiring emergency surgery: report of a case.

We report herein the case of a 17-year-old woman with von Recklinghausen's disease who was diagnosed as having a giant malignant Triton tumor located in the anterior mediastinum, which had adhered to the heart and the great vessels. An emergency operation was performed to relieve the tracheobronchial stenosis and congestive heart failure caused by the pressure of the tumor. Extracorporeal circulation was not required and the tumor could be excised only piece by piece. To our knowledge, this is the first report of a malignant Triton tumor being located in the anterior mediastinum.

Adolescent↗

PubMed1996

Gastric plasmacytoma: report of a case.

A 54-year-old man with primary gastric plasma-cytoma is herein reported. After the patient had been diagnosed as having malignant lymphoma by gastrofiberscopy and a radiologic upper GI examination, a total gastrectomy was performed. Both histological and immunohistochemical studies showed plasmacytoma cells infiltrating the entire stomach wall, producing IgM-lambda, and indicating a final diagnosis of primary gastric plasmacytoma. Monoclonal immunoglobulin was not detected in the serum throughout the course. The case is discussed with reference to other reported cases of primary gastric plasmacytoma.

Gastrectomy↗

PubMed1996

Secundum atrial septal defect associated with mitral valve cleft: report of a case with chromosomal syndrome of trisomy 3p.

A 4-year-old boy was diagnosed as having a chromosomal abnormality with trisomy 3p associated with a secundum atrial septal defect and a cleft of the anterior mitral leaflet. His craniofacial features showed microcephaly, micrognathia, ocular hypertelorism associated with epicanthus, and low-set ears. Moderate mental retardation and hypoplasia of the penis were also noted. A left ventriculogram demonstrated grade 2 mitral regurgitation according to the Sellers' classification with a prolapsing of the mitral leaflets. A cleft of the anterior mitral leaflet was detected at the time of operation. The secundum atrial septal defect was directly closed and the mitral cleft was repaired. This is the first report of trisomy 3p associated with an atrial septal defect and a mitral valve cleft.

Child, Preschool↗

PubMed1996

Rapidly curable biological glue composed of gelatin and poly(L-glutamic acid).

The tissue adhesion property of a hydrogel cross-linked with water-soluble carbodiimide (WSC) was investigated and compared with that of the conventional fibrin glue. The biodegradable hydrogel was composed of gelatin and poly(L-glutamic acid) (PLGA). This study focused on the mouse skin bonding by the WSC-formed hydrogel prepared from a low-molecular-weight (Mw) gelatin whose aqueous solution did not spontaneously set to a gel at 25 degrees C, in contrast to the conventional gelatin with high Mw. At polymer concentrations lower than the incipient gelation concentration, the bonding strength of mouse skin by the WSC-cross-linked gelatin-PLGA hydrogel increased with an increase in the concentration of gelatin and PLGA, irrespective of Mw of gelatin. When compared at the highest gelatin concentration which did not cause gelation, the bonding strength of the hydrogel composed of lower Mw gelatin and PLGA was higher than that of higher Mw gelatin hydrogel with or without PLGA or the conventional fibrin glue. The mixed aqueous solution from the gelatin with Mw of 10,000 and PLGA was gelled by use of WSC as rapidly as the fibrin glue. It was concluded that the gelatin-PLGA hydrogel is a safe biological glue with the adhesion property superior to the fibrin glue.

Adhesives↗

PubMed1996

Aerosol transport and deposition in the rhythmically expanding pulmonary acinus.

Little is known about factors controlling the dynamics of aerosol dispersion and deposition in the lung periphery, though this knowledge becomes increasingly important in many fields such as environmental and occupational exposure, diagnostic applications, and therapeutic deliver of drugs via aerosols. For the last several years, we have been studying aerosol behavior in the pulmonary acinus, where the airway structure and the associated fluid mechanics are distinctly different from those in the conducting airways. Our major research efforts have been focused on the basic physics underlying acinar fluid mechanics and particle dynamics, which are likely to be conditioned by the two key geometric factors of acinar airways: structural alveolation and rhythmic expansion and contraction of the alveolar walls. A combination of computational and experimental analyses revealed that due to these unique geometric features acinar flow can be extremely complex despite the low Reynolds number, and can have substantial effects on particle dynamics. In particular, chaotic mixing can occur in the lung periphery. In the course of such a mixing process, the inhaled aerosol particles quickly mix with the residual alveolar gas in a manner that is radically different from the previously considered classical diffusion process. The objective of this paper is to briefly review our current understanding of these processes, to discuss existing deposition models, and to describe our ongoing research efforts toward a basic understanding of aerosol behavior in the pulmonary acinus.

Administration, Inhalation↗

PubMed1996

Preoperative intra-arterial infusion chemotherapy for invasive thymoma: a case report.

A 24-year-old man was diagnosed as having mixed-type thymoma by preoperative percutaneous needle biopsy. A chest computed tomogram showed a tumor measuring 12x9 cm. Selective intra-arterial infusion chemotherapy was first selected because invasion to the superior vena cava was suspected. Bolus injection of 50 mg/m2 cisplatin and 20 mg/m2 adriamycin was performed once into the right internal thoracic artery. The resulting decrease in tumor size was 81%. Neither complications due to the infusion procedure nor side effects due to the anticancer drugs were encountered. An extended thymectomy with partial resection of the mediastinal pleura was safely performed. The histological diagnosis of the resected tumor was thymic hyperplasia. The patient was transferred to a radiologist for additional radiotherapy. Selective intra-arterial infusion chemotherapy for invasive thymoma is an effective therapy, producing no significant side effects and allowing safe resection.

Adult↗

PubMed1996

Health information system.

Outline of selected ones among a number of nationwide surveys related to health and welfare services (90 surveys as of 1995) conducted mainly by the Ministry of Health and Welfare periodically in Japan is described. That is, history, purpose, coverage, date, contents, data collection procedure, tabulation and publication were explained in regard to : (1) Population Census, (2) Vital Statistics, (3) Patient Survey, (4) Infectious Disease Surveillance System, (5) Comprehensive Survey of Living Conditions of People on Health and Welfare, (6) Census on Medical Care Institutions, (7) Hospital Report, (8) Survey on Physicians, Dentists and Pharmacists, (9) Statistical Report on Public Health Administration Services, (10) Survey on Social Welfare Institutions, and (11) National Nutrition Survey. On-line data service system of the Ministry of Health and Welfare is also briefly mentioned.

Demography↗

PubMed1996

[Modified surgery for early gastric cancer].

Based on the sufficiently accumulated results of early gastric cancer (EGC), particularly the diagnostic accuracy regarding the depth of cancerous involvement in the gastric wall, lymph node metastasis, pattern of recurrence etc., the modified surgery has been induced for the treatment of EGC since late 1970's. The modification is as follows depending on the depth and location of EGC: constriction of size of gastric resection; narrowing of the extent of lymphadenectomy; preserving omentum, pancreas, spleen, pylorus, vagal nerve, lower esophageal sphincter etc; sparing thoracotomy. This kind of surgery has resulted in remarkable reduction of blood loss during surgery, reduced operation time and hospital stay, which have brought improved QOL to the patients as well as satisfactory survival rate after surgery.

Aged↗

PubMed1996

[Laparoscopic surgery for early gastric cancer].

We have successfully treated 40 patients with early gastric cancer by using two different laparoscopic procedures since March 1992, which are laparoscopic wedge resection of the stomach using a lesion-lifting method (n = 25) and laparoscopic intragastric mucosal resection (n = 15). The indication is as follows; 1) mucosal cancer, 2) < 25 mm, if the lesion is protruded type, 3) < 15 mm and U1 (-), if the lesion is depressive type. All patients were discharged within 4-8 days uneventfully. The resected specimens were 66 +/- 16 mm and 48 +/- 8 mm in diameter respectively, and had a sufficient surgical margin horizontally (16 +/- 5 mm, 8 +/- 4 mm) and vertically. Histology revealed they were all curative surgeries except one case in whom an additional gastrectomy with lymph node dissection by laparotomy was required one month after surgery because lymphatic invasion had been revealed by pathology. In conclusion, these laparoscopic procedures are curative and minimally invasive treatment for early gastric cancer.

Adult↗

PubMed1996

[Laparoscopic curative surgery for early gastric cancer].

We have successfully treated 40 patients with early gastric cancer by using two different laparoscopic procedures since March 1992, which are laparoscopic wedge resection of the stomach using a lesion-lifting method (n = 25) and laparoscopic intragastric mucosal resection (n = 15). The indication is as follows; 1) mucosal cancer, 2) < 25 mm, if the lesion is protruded type, 3) < 15 mm and Ul(-), if the lesion is depressive type. All patients were discharged within 4-8 days uneventfully. The resected specimens were 66 +/- 16 mm and 48 +/- 8 mm in diameter respectively, and had a sufficient surgical margin horizontally (16 +/- 5 mm, 8 +/- 4 mm) and vertically. Histology revealed they were all curative surgeries except one case in whom an additional gastrectomy with lymph node dissection by lapalotomy was required one month after surgery because lymphatic invasion had been revealed by pathology. In conclusion, these laparoscopic procedures are curative and minimally invasive treatment for early gastric cancer.

Gastrectomy↗

PubMed1996

Immediate tonsillectomy for peritonsillar abscess.

The usual treatment for peritonsillar abscess (PTAs) in Japan is antibiotic therapy, drainage and incision followed by tonsillectomy several weeks later. This is a retrospective study of cases treated by immediate tonsillectomy (IT) for PTAs between January 1990 and February 1995 in our hospital. There were 119 cases, 94 male and 25 female, ranging in age from 14 to 76 years (average: 36.6). In all cases, we performed CT scan, which is the most reliable diagnostic method for PTAs. Five of the 119 cases were treated by IT under general anesthesia. All five were male and their ages ranged from 50 to 62 years (average: 56.2). Two patients had diabetes mellitus. Bacteriological study revealed alpha-Streptcoccus in 1 case, but the others showed no remarkable findings. Anaerobacteria were not found in any patient. IT under general anesthesia is preferable for advanced PTAs.

Abscess↗

PubMed1996

Hepatic embolization through extrahepatic collateral pathways after hepatic arterial embolization for the hepatocellular carcinoma.

Extrahepatic collateral pathways developing after repeated transcatheter arterial embolization (TAE) for hepatocellular carcinoma (HCC) make therapeutic arterial embolization for recurrent lesions extremely difficult. TAE was performed through the collateral pathways using a sophisticated micro-catheter with good trackability and pushability and a coaxial system. Twenty-three TAEs were undertaken through the collateral pathways in 13 patients with recurrent HCC who had extrahepatic collateral pathways after the previous hepatic arterial TAE. There were 69 extrahepatic collateral pathways, with partially obstructed hepatic arteries. On the average, three feeding arteries were seen in the liver. The main extrahepatic collateral pathways were the inferior phrenic artery and epicholedocal artery, 18 vessels and 29 vessels, respectively, accounting for about 80% of the total collateral pathways. TAEs were successful in all cases and the number of embolized vessels was 2.1 on average. The average time of the first collateral TAE after the initial conventional hepatic arterial TAE was 2.3 years. Excellent prognosis was observed with a one-year survival rate of 77% and 3-year survival rate of 38% after the collateral TAE. We consider that collateral TAE for recurrent HCC with obstruction of the hepatic artery is the procedure of choice, is technically feasible, and provides better prognosis for the patients.

Adult↗

PubMed1995

Antitumor activity of cis-diamminedichloroplatinum (II) depends on its time x concentration product against human gastric cancer cell lines in vitro.

A pharmacodynamic study of cisplatin (DDP) was conducted using the gastric cancer cell lines MKN-45 and MKN-74 in vitro. Ten thousand tumor cells were incubated with 0.4-500 micrograms/ml DDP for 1-25 h, followed by recovery culture for a further 48 h. At the end of incubation, cell viability was detected by the MTT end-point, and the inhibition rate was compared in relation to the incubation time, DDP concentration, and the time X concentration product (area under the curve in vitro: AUC vitro). In both of the cell lines, the IC50 and IC90 values decreased as the exposure time increased, going a linear curve with a slope of almost -1, and showing a typical log-log AUC vitro-dependent curve. These results indicate that the antitumor activity of DDP is dependent on its AUC vitro, suggesting the clinical usefulness of this drug when administered daily in small divided doses.

Antineoplastic Agents↗

PubMed1995

Successful surgical management of emphysematous giant bullae accompanied by severe bronchial asthma: report of a case.

The surgical treatment of emphysematous lung bullae is usually contraindicated in patients with severe bronchial asthma. However, we recently encountered a patient who required surgery due to the development of respiratory distress despite treatment with bronchodilators and low-dose prednisolone (5 mg/day). During the first operation, bronchospasm occurred with anesthesia. After suppression of the asthmatic symptoms for 2 weeks with high-dose prednisolone (25 mg/day), the giant bullae could be resected safely. Thus, the preoperative resolution of asthma to decrease the probability of an attack is indispensable for such patients.

Adult↗

PubMed1995

Extracorporeal membrane oxygenation for respiratory failure.

We report herein our experience with extracorporeal membrane oxygenation (ECMO) for respiratory failure over a 3-year period. ECMO was employed in seven patients: in five for respiratory failure caused by adult respiratory distress syndrome (ARDS), Goodpasture's syndrome, hypoxia after ventricular septal defect closure, interstitial pneumonia, or lung metastasis from choriocarcinoma; and in two for tracheal obstruction. Nafamostat mesilate was used as the main anticoagulant with a small amount of heparin. The period of ECMO support for the five patients with respiratory failure ranged from 54 to 251 h, with an average time of 125 h. Five of the seven patients were able to be weaned from ECMO, and the two who had tracheal obstruction survived. The other three patients who were weaned from ECMO died of underlying diseases or complications 1-25 days after weaning. The complications which occurred during ECMO support were an abnormal electroencephalogram, multiple organ failure, and mediastinitis. Thus, we conclude that ECMO needs to be induced early to obtain a better outcome in patients with respiratory failure, and that it is particularly effective for transient airway obstruction.

Adult↗