PubMed Health⌕ Search

Biomedical subjects

T Obama

Publications and source records attributed to T Obama.

At least 19 recordsLinked to original sources
PubMed2006

[Thoracic surgery for the penetrating lung or tracheal trauma].

Seven cases suffered from a chest trauma (stab wound in 6 and impalement injury in 1) were emergently transferred to our hospital. Open thoracotomy was performed for the intolerable bleeding immediately after admission. Injured lung was treated by lobectomy in 1 patient, lingual segmentectomy in 2, lower basal segmentectomy in 2, partial resection in 4 and direct suture in 2. The penetrating trachea was carefully repaired by direct suture with additional midsternal thoracotomy. To accomplish appropriate partial resection of the injured lung, a metallic straight suction tube inserted into a pulmonary stab wound was retracted and a stapling instrument was applied underneath the suction tube. With the segmentectomy and the partial resection, the volume of the residual lung was maximally saved. As a result, all 7 patients were successfully alive.

Adult↗
PubMed2004

[Strategy for surgical treatment for small peripheral carcinoma of the lung especially on systemic nodal dissection].

The diagnosis of small-sized (< or = 2 cm) non-small cell lung cancer (NSCLC) has increased with the development of computed tomography (CT), whereas unexpected extensive mediastinal involvement has been occasionally detected in such a small-sized lung cancer. We retrospectively analyzed the clinicopathological features to determinate the predictors for lymph node involvement in patients with a small-sized adenocarcinoma. One hundred and eighty one patients who underwent pulmonary resection and systematic nodal dissection for a peripheral small-sized adeno-carcinoma were reviewed. Of these, 24 patients (13.3%) had lymph node involvement. These patients were divided into 2 groups according to the existence of lymph node involvement, and the predictors for lymph node involvement were determined using univariate analysis and multivariate regression analysis. Univariate analysis revealed GGOR (ground glass opacity area/tumor area at the level of the greatest dimension of the lesion on chest computer tomography) > or = 25% (p = 0.0137) and pleural lavage fluid involvement (p = 0.0467) as predictors for lymph node involvement. No patients had lymph node involvement if their GGOR was higher than 50%. Multivariate regression analysis revealed GGOR > or = 25% (p = 0.0274), pleural tags on the lesion on chest CT (p = 0.0138) and pleural lavage fluid involvement (p = 0.0415) as predictors. We recommend performing systemic nodal dissection even if small peripheral adeno-carcinoma's maximal diameter is 20 mm or less. Systemic nodal dissection is unnecessary if the patients' GGOR > or = 50% or they do not have pleural tags or pleural lavage fluid involvement.

Aged↗
PubMed2004

[Removal of a steel bar after Nuss procedure for pectus excavatum; report of a case].

Recently, an increasing number of patients have been treated with the Nuss procedure for pectus excavatum. One of the merits is that this surgical procedure is less invasive and leads to good cosmetic results compared with the former traditional procedures such as sternal turn over. We have repaired 60 cases of pectus excavatum using the Nuss procedure at our institute since July 1999. We have experienced the removal of a steel bar, which was the first case of Nuss procedure at our institute.

Child↗
PubMed2003

[Surgery for metastatic lung tumors at our department during the last ten years].

We report on 86 cases (112 operations) who underwent surgery for metastatic lung tumors at our department during the last 10 years. The study subjects comprised 53 men and 33 women, and the average age was 51 (+/- 19) years. Of the 112 metastatectomies performed, 53 were conducted by video-assisted thoracic surgery (VATS), and 59 were performed via thoracotomy. The procedures employed for metastatectomy were lobectomy (22 cases), segmentectomy (4 cases), and partial resection. wedge resection (86 cases). The primary origin of the metastatic tumors was colorectal carcinoma in 22 cases, osteosarcoma in 13 cases, renal carcinoma in 10 cases, and breast carcinoma in 6 cases. The 5-year survival rates in subjects undergoing first and second resection for pulmonary metastases were 46% and 44%. Metastatectomy was performed 1, 2, 3, 4, 5, and 7 times in 73, 7, 1, 2, 2, 1 cases, respectively. The average number and maximum diameter of the metastatic pulmonary lesions at first metastatectomy were 1.9 and 27.6 mm. Metastatectomy is performed, as a rule, by VATS at our department, because the more highly invasive thoracotomy procedure influences the activity of the cancer cells in a suspended phase in an unfavorable manner. Furthermore, we believe that to the maximum extent possible, re-metastatectomy should also be performed by VATS. The survival rates at our institution have been satisfactory, and we attribute this to our following strict indications for metastatectomy. Re-metastatectomy should always be considered, as the survival rates are as favorable as those following the first metastatectomy.

Adult↗
PubMed2002

[Multiple primary lung carcinoma].

Of 692 patients who underwent operations for primary lung carcinoma between January 1980 and August 2001, 21 (3.0%) were considered to have a second primary lung carcinoma, which was synchronous in 14 cases (2.0%) and metachronous in 7 cases (1.0%). Five-year survival rate for patients with synchronous and metachronous disease from initial treatment of carcinoma were 66.7% and 100%, respectively. Survival after the development of a metachronous lesion was 80.0% at 5 years. Eight of the synchronous second tumors (57%) were detected by preoperative radiography or bronchoscopy, and 3 (21%) were detected during the operation. Adenocarcinoma comprised 81% of all multiple primary lung carcinomas, 86% of synchronous carcinomas and 57% of metachronous carcinomas. It is important to carefully examine a synchronous lesion before and during the operation of a primary lung carcinoma and to perform close follow-up surveillance for early detection of a metachronous lesion. The outcomes of surgical treatment for either synchronous or metachronous multiple primary lung carcinomas are satisfactory. Precise staging is important for the treatment of multiple lung carcinomas, and an aggressive surgical approach should be considered for early-stage carcinomas.

Adult↗
PubMed2002

[Concomitant lobectomy by video-assisted thoracic surgery and coronary artery bypass grafting: report of a case].

Successful simultaneous operation for cardiac and lung disease was performed in a 71-year-old man with lung carcinoma and ischemic heart disease. Chest CT scan revealed a mass in the right lower lobe and absence of mediastinal lymphadenopathy. Coronary angiography revealed significant stenosis of the left anterior descending artery, circumflex artery and right coronary artery. We performed concomitant video-assisted right lower lobectomy with mediastinal lymph node dissection as a form of less invasive surgery and triple coronary artery bypass grafting under cardiopulmonary bypass. Curative surgery for lung carcinoma and complete revascularization for ischemic heart disease were completed. The postoperative course was uneventful.

Adenocarcinoma↗
PubMed2002

[Rupture of type III acute aortic dissection into the bilateral pleural space: report of a case].

Rupture of type III aortic dissection into the bilateral pleural space is very rare. A 62-year-old man was transferred to our department because of aortic dissection for emergency operation. computed tomography (CT) scan revealed rupture of type III aortic dissection into the bilateral pleural space. He underwent successful prosthetic graft replacement through left thoracotomy and removal of a massive amount of blood from the right pleural space by chest tube drainage. The postoperative course was uneventful after 2 days of respiratory support.

Aortic Dissection↗
PubMed2000

[Video-assisted minithoracotomy versus conventional posterolateral thoracotomy for performing lobectomy of lung carcinomas].

This study was performed to evaluate the advantages of video-assisted minithoracotomy over conventional posterolateral thoracotomy for performing lobectomy of lung carcinomas. Thirty-two patients with clinical T1N0M0 non-small cell lung carcinoma underwent lobectomy with R2a mediastinal lymphadenectomy. Of these, sixteen patients underwent posterolateral thoracotomy (between April 1994 and November 1995: T group), and sixteen patients underwent video-assisted thoracic surgery (between December 1997 and April 1999: V group). No significant differences were found in the two groups with respect to the total number of mediastinal lymph nodes dissected (T group: 16.9 +/- 8.7. V group: 14.3 +/- 7.2) or operative time (T group: 182.3 +/- 48.8 min, V group: 174.9 +/- 28.8 min). The intraoperative blood loss was significantly less in the V group (T group: 222.3 +/- 107.1 ml, V group: 143.3 +/- 92.6 ml, p < 0.05), and the postoperative max CPK was also less (T group: 1,484 +/- 496, V group: 785 +/- 327, p < 0.0001). Duration of chest tube drainage (T group: 11.3 +/- 3.6 days, V group: 7.9 +/- 2.7 days) and the requirement of epidural analgesia (T group: 6.7 +/- 2.2 days, V group: 5.0 +/- 0.8 days) were less in the V group (p < 0.01), and the length of postoperative hospitalization as also shorter in the V group (T group: 26.3 +/- 8.3 days, V group: 20.6 +/- 4.1 days, p < 0.05). In conclusion, video-assisted minithoracotomy is less invasive than posterolateral thoracotomy for performing lobectomy of lung carcinomas, and has an advantage in that it improves the postoperative quality of life.

Aged↗
PubMed1999

Extended survival of a porcine mitral bioprosthesis for 23 years: report of a case.

Limited durability is the major drawback of bioprosthetic valves, few of which survive for as long as 20 years. We report herein the case of a patient we recently encountered in whom a bioprothesis lasted for 23 years. To our knowledge, this is only the second case of such long survival. The patient was a 56-year-old man who was urgently admitted to our hospital with acute mitral regurgitation, 23 years after undergoing mitral valve replacement with a porcine bioprosthesis. Acute leaflet tears were found to be the cause of the mitral incompetence and the xenograft was successfully replaced with a mechanical valve. We believe that when reoperation is thought to carry a low risk, prophylactic surgery might be justified, even in patients without symptoms.

Bioprosthesis↗
PubMed1999

[Clinical study of six thymic carcinomas including long-term survivors].

Six cases of thymic carcinoma (mean age 48.5 years old, one male and 5 females) were treated in our hospital from September 1990 to September 1998. The histological subtypes of thymic carcinoma were squamous cell in 4, undifferentiated in one, and small cell in one. All cases underwent midsternal thoracotomy, 4 had total resection of the tumor and 2 had exploratory thoracotomy due to tumor invasion of the aorta and the main pulmonary artery. Within 2 years after operation, 2 cases without radiation therapy were died of the carcinoma and one case was died of asthma. However, two cases of squamous cell carcinoma have been alive and disease free for 3 and 5 years since the operation followed by mediastinal irradiation. We think that radiation therapy is very effective to control the disease because one of them underwent only exploratory operation prior to irradiation. Another one case who survives 5 years after total resection of the tumor following irradiation revealed swelling of numerous mediastinal lymph nodes, pathologically consisted of non-caseating epithelioid cell granulomas without metastasis of carcinoma, at the time of operation. These lymph nodes were diagnosed as "sarcoid-like reaction" because there was no clinical evidence of generalized sarcoidosis. The "sarcoid-like reaction" may contribute to the 5-year survival of the patient because it is thought to be a local immune response against the cancer cells. A remaining patient, alive 6 months after total resection of the thymic small cell carcinoma following irradiation, received preoperatively three cycles of the intra-arterial administration using CBDCA via bilateral internal mammary arteries. This induction chemotherapy had no response of the tumor size, but it was considered to have a possibility of reducing the size of thymic carcinoma by the use of other agents (CDDP, VDS etc.) because the tumor was fed mainly by the highly developed internal mammary arteries.

Adult↗
PubMed1999

[Complete disruption of thoracic descending aorta without widening of the pseudoaneurysm].

A 41-year-old male was transported to our emergency room 25 minutes after blunt chest trauma. The chest X-ray film and CT scanning demonstrated left pulmonary atelectasis, hemothorax, and widening of mediastinum possibly due to hematoma. Hundred and fifty minutes after arrival to the hospital, we were rush to bring him to the operation theater suspecting serious injury of the thoracic organs in association with bleeding from left thoracic drainage tube without detection of the aortic rupture. The left standard thoracotomy disclosed no injury of the left lung, good continuity and no dilatation of the thoracic descending aorta. But visual blood flow observed through the adventitia of the aortic isthmus led us to the final diagnosis of the aortic rupture. After aortic clamping, the intima of the injured aorta was found to be completely disrupted for a length of 6 cm and was repaired with a vascular prosthesis under the partial cardiopulmonary bypass using a centrifugal pump. His postoperative course was uneventful. We reported a case of complete circumferential aortic rupture without widening of the pseudoaneurysm in the acute stage of the disease.

Adult↗
PubMed1998

Minimally invasive cardiac surgery with surgical ablation of atrial fibrillation.

Surgical ablation for atrial fibrillation with mitral valve operations has been often performed in patients who have chronic atrial fibrillation associated with mitral valve disease. We describe a case of the combined operation through a small incision. A 49-year-old woman presented with a 1-month history of left hemiplegia. Echocardiography confirmed mitral stenosis and electrocardiogram revealed atrial fibrillation. The duration of the atrial fibrillation before admission was 12 years. Mitral commissurotomy, removal of clots, and surgical ablation for atrial fibrillation was performed through an 8-cm right parasternal incision. The right femoral artery and vein were used for cannulation. Another cannula was inserted into the superior vena cava. The extended use of cryoablation was carried out instead of atriotomy or reanastomosis. The patient was extubated for 5 hours after the operation. Atrial fibrillation was converted to a sinus rhythm. On the basis of our experience, this procedure seemed promising.

Atrial Fibrillation↗
PubMed1998

Right parasternal minithoracotomy for repair of atrial septal defect.

Various surgical approaches for repair of atrial septal defect (ASD) have recently been introduced for superior cosmetic and less invasive results. A technique for repair of isolated ASD through a small right parasternal minithoracotomy is described. In spite of the smaller incision, there is no need to use femoral cannulation or video-assisted endoscopy. This approach is simple, less invasive, and cosmetic. We believe that right parasternal minithoracotomy is a suitable alternative to a median sternotomy for ASD closure, especially in young male patients.

Adolescent↗
PubMed1993

Non-competitive antagonism by hirsuteine of nicotinic receptor-mediated dopamine release from rat pheochromocytoma cells.

Effects of hirsuteine, an indole alkaloid extracted from Uncaria genus, on nicotine- and high K-induced responses were investigated in rat pheochromocytoma PC12 cells. Hirsuteine (300 nM-10 microM) inhibited dopamine release evoked by 100 microM nicotine in a concentration-dependent manner. Hirsuteine did not produce a parallel shift of the concentration-response relationship curve for nicotine, but reduced maximal dopamine release. Dopamine release evoked by 60 and 155 mM KCl was also inhibited by hirsuteine, but the concentration necessary for significant inhibition was higher (more than 10 microM). Under whole cell voltage-clamp, hirsuteine reversibly inhibited inward currents activated by 100 microM nicotine. The current inhibition was slightly accelerated by hyperpolarization. The results suggest that hirsuteine non-competitively antagonizes nicotine-evoked dopamine release by blocking ion permeation through nicotinic receptor channel complexes. The blockade of Ca channels, which are activated during nicotine-evoked depolarization, may not play a major role in the antagonism.

Adenosine Triphosphate↗
PubMed1991

Selective and competitive antagonism by suramin of ATP-stimulated catecholamine-secretion from PC12 phaeochromocytoma cells.

1. Suramin, a putative P2-antagonist, (10 to 300 microM) inhibited the adenosine 5'-triphosphate (ATP)-stimulated secretion of [3H]-noradrenaline or endogenous dopamine from phaeochromocytoma PC12 cells in a concentration-dependent manner. Suramin (300 microM) did not affect the dopamine-secretion stimulated by high K+ or nicotine. 2. Suramin shifted the concentration-response curve for ATP to the right. The antagonism was competitive with a pA2 value of 4.52. 3. ATP also stimulated an increase in intracellular Ca2+ concentration as determined by fura-2 methods. Suramin antagonized this effect over the same concentration range that antagonized the ATP-stimulated catecholamine secretion. 4. These results suggest that suramin can be used as a selective and competitive antagonist of ATP in experiments concerning mechanisms of catecholamine-secretion.

Adenosine Triphosphate↗
PubMed1991

Antagonism by reactive blue 2 but not by brilliant blue G of extracellular ATP-evoked responses in PC12 phaeochromocytoma cells.

1. The effects of reactive blue 2 and brilliant blue G, which have been shown to block extracellular ATP-evoked responses, were investigated to discover whether these compounds act as P2-purinoceptor antagonists in PC12 phaeochromocytoma cells. 2. Reactive blue 2 (10 to 100 microM) suppressed the ATP-stimulated dopamine secretion from PC12 cells in a dose-dependent manner. The concentration-response curve for ATP was shifted to the right and the maximal response was decreased by reactive blue (30 and 100 microM). Brilliant blue G (up to 100 microM) did not significantly affect the secretion. 3. Reactive blue 2 (10 to 100 microM) suppressed the ATP-activated inward current recorded from the voltage-clamped cells in a concentration-dependent manner. Brilliant blue G (up to 100 microM) did not affect the current. 4. The results suggest that reactive blue 2 but not brilliant blue G is a P2-purinoceptor antagonist in PC12 cells. The purinoceptors in these cells may be the same type as those involved in ATP-evoked smooth muscle relaxation, judging from the antagonism by reactive blue 2.

Adenosine Triphosphate↗
PubMed1991

Inhibitory action of peripheral-type benzodiazepines on dopamine release from PC12 pheochromocytoma cells.

Characteristics of the benzodiazepine inhibition of dopamine (DA) release in PC12 cells were investigated. Diazepam inhibited DA release evoked by high concentrations of extracellular K+ in a dose-dependent manner (IC50, 10 microM). Ro 5-4864 [7-chloro-1,3-dihydro-1-methyl-5-(p-chlorophenyl)-2H-1,4-benzodiazepine- 2-one], a peripheral-type benzodiazepine, also inhibited DA release effectively. PK 11195 [1-(2-chlorophenyl)-N-methyl-N-(1-methyl-propyl)-3-isoquinoline carboxamide], a benzodiazepine generally considered a peripheral-type benzodiazepine receptor antagonist, did not antagonize the inhibition induced by diazepam, but rather inhibited DA release itself. On the other hand, the central-type benzodiazepines, clonazepam and Ro 15-1788 (ethyl-8-fluoro-5,6-dihydro-5-methyl-6-oxo-4H-imidazo[1,5a] [1,4]benzodiazepine-3-carboxylate) did not affect the DA release. Diazepam, Ro 5-4864 and PK 11195 also inhibited a Ba(++)-current carried by voltage-gated Ca++ channels, and diazepam suppressed an increase in intracellular Ca++ evoked by 80 mM extracellular K+ as measured by the fura-2 method. These results suggest that the inhibitory action of diazepam and other benzodiazepines on DA release from PC12 cells may be mediated through one type of peripheral-type benzodiazepine receptors which are coupled to voltage-gated Ca++ channels and that these receptors may not necessarily be the same as those in other tissues.

Animals↗