Induction of glutathione peroxidase in response to inactivation by nitric oxide.

To determine effect of nitric oxide (NO) on cellular glutathione peroxidase (GPX) level in living cells, we measured the activity, protein and mRNA of GPX in rat kidney (KNRK) cells under a high NO condition. Combined treatment of lipopolysaccharide (LPS, 1 microgram/ml) and tumor necrosis factor-alpha (TNF-alpha, 50 ng/ml) synergistically enhanced (23-folds) nitrite production from KNRK cells. This was suppressed by an inducible NO synthase (iNOS) inhibitor (aminoguanidine, N-nitro-L-arginine methylester hydrochloride) and arginase. iNOS expression was detected by RT-PCR in the treated cells. GPX was inactivated irreversibly when the cells had been homogenized before exposure to a NO donor, S-nitroso-N-acetylpenicillamine (SNAP). In living KNRK cells, SNAP and LPS + TNF-alpha exerted a transient effect on the GPX activity. The treatment with SNAP (200 microM) or sodium nitroprusside (200 microM) enhanced GPX gene expression, which was blocked by a NO scavenger, 2-phenyl-4,4,5,5,-tetramethylimidazoline-1-oxyl-3-oxide. GPX mRNA was markedly increased by the treatment with LPS + TNF-alpha, and aminoguanidine blocked the effect. In cells metabolically labeled with 75Se, LPS + TNF-alpha accelerated the incorporation of radioactivity into GPX molecule by 2.1-fold. These results suggest that inactivation of GPX by NO triggers a signal for inducing GPX gene expression in KNRK cells, thereby restoring the intracellular level of this indispensable enzyme.

[Clinical experience in thoracoscopic left internal mammary artery harvesting with voice activated robotic assistance].

Between September 1998 to February 2000, 45 consecutive patients underwent robotic-assisted, video-enhanced coronary artery bypass grafting. All IMA's were harvested using the voice-activated robotic assistant (AESOP 3000, Computer Motion Inc, Santa Barbara, CA) and the Harmonic scalpel (Ethicon Endo-Surgery, Cincinnati, OH). Left IMA's were successfully harvested in all patients. Harvested IMA's were anastomosed to LAD's under direct vision through limited left anterior thoracotomy. The IMA harvest time was 57.8 +/- 23.2 min, intraoperative graft flow was 34.3 +/- 20.5 ml/min, postoperative hospital stay was 3.9 +/- 1.5 days. The early postoperative angiogram showed that all grafts were patent. There was no mortality, no significant morbidity. The robotic assisted, video enhanced CABG provides safe and complete LIMA dissection with minimal manipulation and assures sufficient LITA length for tension free anastomosis.

[Surgical results of canal wall reconstruction tympanoplasty in middle ear cholesteatoma].

Materials were 236 ears of 213 patients with middle ear cholesteatoma undergoing canal wall reconstruction during 1993-1998. Subjects were followed up for at least 1 year after final operation. Of 236 ears, 147 (62%) underwent 1-stage operation and 89 ears (38%) required 2-stage operation. Hearing results were successful in 157 ears (67%) based on criteria proposed by the Otological Society of Japan. The success in ears undergoing 1-stage operation was 74% and 54% in ears undergoing 2-stage operation. Postoperative hearing and air-bone gap in the 1-stage group were significantly better than in the 2-stage group. For tympanoplasty, success was 97% in type I, 64% in type III, and 53% in type IV. The likelihood of undergoing 2-stage operation increased with the type of tympanoplasty, from type I to IV. Postoperative hearing was significantly worse in older age groups. Of the 89 ears, 13 (15%) had recurrent cholesteatoma and 29 (33%) had residual cholesteatoma at 2-stage operation. In the 135 in the 1-stage group, recurrent cholesteatoma was observed at follow-up in 13 ears (9.6%). When we analyzed clinical risk factors for both recurrent and residual cholesteatoma in age, gender, otorrhea, types of cholesteatoma, and types of tympanoplasty, no significant factors were seen for recurrent or residual cholesteatoma. These results indicate that canal wall reconstruction tympanoplasty for middle ear cholesteatoma yields relatively good hearing results. However, more effort is needed to reduce the incidence of recurrent and residual cholesteatoma.

Hearing results of canal wall reconstruction tympanoplasty for middle ear cholesteatoma in children.

OBJECTIVE: To investigate post-operative hearing results in children with middle ear cholesteatoma, and to analyze the correlation between hearing results and clinical factors and findings before and during the operation. PATIENTS AND METHODS: One hundred and twenty-four ears of 123 children were operated on for middle ear cholesteatoma at the age of 10 years or younger by canal wall reconstruction tympanoplasty and were followed up more than 1 year after the final operation. We evaluated the average air and bone conduction hearing levels at the speech ranges before the first operation (pre-operative hearing) and after the final operation (post-operative hearing). RESULTS: The mean of the average air conduction hearing level of 124 ears was significantly improved from 34.7 to 27.1 dB after the final operation. Among them, 84 ears (67.8%) showed a hearing level of 30 dB or less post-operatively. Post-operative hearing was better in the one-stage group than in the staged group. However, more than one-half of the ears which underwent type IV tympanoplasty in the staged group showed post-operative air conduction hearing level of < or =30 dB. Significant improvement in post-operative hearing was noted in ears with normal middle ear mucosa or middle ear effusion at the final operation. No correlation between hearing improvement and clinical factors such as age, type of cholesteatoma or presence of otitis media with effusion at the first operation was found. CONCLUSIONS: Children with middle ear cholesteatoma at the age of 10 years or younger exhibited good hearing post-operatively. Satisfactory hearing improvement is expected even in ears without the superstructure of the stapes if staged tympanoplasty is conducted. Canal wall reconstruction tympanoplasty for pediatric cholesteatoma was successful in terms of hearing results and the success was unrelated to various clinical factors.

Effect of obesity and troglitazone on expression of two glutathione peroxidases: cellular and extracellular types in serum, kidney and adipose tissue.

To determine the effect of obesity on expression of cellular- (C-) and extracellular (EC-) glutathione peroxidase (GPX) in serum, kidney and adipose tissue, we measured GPX in serum, kidneys and adipose tissue of the obese Otsuka-Long-Evans-Tokushima Fatty (OLETF) rat and its lean counterpart (LETO). We also investigated the effect of troglitazone. Five each of OLETF and LETO rats were fed diet with or without 0.2% troglitazone for 10 days. Final body weight, kidney weight, blood glucose and serum tumor necrosis factor-alpha (TNF-alpha) level were higher in OLETF rats than in LETO rats. Serum and kidney GPX activities were higher, but adipose tissue GPX activity was lower, in OLETF rats than in LETO rats. Troglitazone treatment decreased adipose tissue GPX activity and abolished overproduction of TNF-alpha in OLETF rats. Immunoblot analysis, for the first time, revealed that both obesity and troglitazone suppressed the protein signals for C-GPX and EC-GPX in adipose tissue. Serum protein carbonyl groups were increased in OLETF rats and troglitazone completely blocked this increase. Increased serum GPX activity in obese rat was due to the increased secretion of EC-GPX from the kidney. Troglitazone protected against the enhanced oxidative stress induced by obesity independently of the serum GPX concentration.

Mitral insufficiency associated with primary antiphospholipid syndrome and chronic renal failure.

We report a case of 52-year-old woman with primary antiphospholipid syndrome who developed mitral insufficiency and chronic renal failure. Continuous ambulatory peritoneal dialysis was started preoperatively due to thrombocytopenia that was aggravated by hemodialysis. Mitral annuloplasty was performed since the mitral valve was not severely damaged. Her postoperative hemodynamics were stable, and anticoagulant therapy was controlled easily. She recovered from severe thrombocytopenia while on continuous ambulatory peritoneal dialysis. Valvular heart disease is a well known feature of primary antiphospholipid syndrome, and there have been several reports about valve replacement in patients who had antiphospholipid syndrome with or without systemic lupus erythematosus. However, valve repair has been reported in only a few such patients. We believe that valve repair is better than valve replacement in patients with antiphospholipid syndrome because of its hypercoagulable tendency. In addition, it seems that continuous ambulatory peritoneal dialysis is a suitable method for the perioperative management of patients with antiphospholipid syndrome who suffer from chronic renal failure as well as thrombocytopenia, and require cardiac surgery under cardiopulmonary bypass.

Extra-anatomic bypass graft for management of axillary artery occlusion in pitchers.

OBJECTIVE: Our goal was to evaluate the long-term results of vein bypass grafts for axillary artery occlusion, specifically those placed extra-anatomically to prevent arterial injury in pitchers. METHODS: With the greater saphenous veins used as the selected conduit, arterial bypass grafts were routed anterior to the pectoralis minor muscle in four baseball pitchers who had occlusion of the axillary artery. We performed a follow-up in excess of 10 years with evaluations of the bypass grafts by ultrasonic duplex scan and magnetic resonance angiography. RESULTS: All four pitchers treated in this manner returned to the game and played for several seasons without a recurrence of the arterial injury. Long-term evaluation of the bypass grafts did not reveal any structural or functional disorder. CONCLUSIONS: Axillary artery occlusion in an athlete can be effectively treated with a vein bypass graft placed extra-anatomically, anterior to the pectoralis minor muscle. The greater saphenous vein should be considered the conduit of choice.

Metastasis of cervical esophageal carcinoma to the temporal bone--a study of the temporal bone histology.

A 49-year-old male developed left abducens nerve palsy as a result of metastatic spread of carcinoma of the cervical esophagus to Rouviere's node and infiltration of the petrous portion of the left temporal bone. Postmortem temporal bone histology revealed that cancer cells had invaded the greater superficial petrosal nerve (GPN), lesser superficial petrosal nerve, tensor tympani muscle (TTM) and the skin covering the anterior wall of the left external auditory meatus. These findings suggest that the carcinoma metastasized from the cervical esophagus to Rouviere's node and directly invaded the middle cranial fossa and then the temporal bone, and further infiltrated the middle ear via perineural invasion.

An alternative arterial conduit for totally endoscopic multivessel coronary artery bypass.

BACKGROUND: The ultimate goal of coronary artery bypass grafting (CABG) is the performance of a totally endoscopic procedure using multiple arterial conduits. At our center we have been routinely performing endoscopic robotic harvesting of internal thoracic arteries (ITAs) for use in minimally invasive CABG. The right gastroepiploic artery (RGEA) has been shown to be a reliable and versatile arterial conduit for bypass to coronary vessels not easily accessible by an ITA. The RGEA has already been harvested less invasively through a small laparotomy. This procedure could be made even less invasive by harvesting the RGEA laparoscopically, but this procedure has not yet been reported. The purpose of this study was to develop an endoscopic technique for harvesting the RGEA and demonstrate the safety and efficacy of this less invasive approach. METHODS: Twenty Duroc X Hampshire swine were administered general anesthesia and intubated. Ten mm and 5 mm trocars were then inserted. A 10 mm, 30-degree endoscope was adapted to a voice-activated robotic arm (AESOP), and the RGEA was harvested totally endoscopically using 5 mm harmonic scalpel shears. Intraoperative events and RGEA harvest times were recorded, and RGEA flows were measured after harvest. RGEA was delivered into the pericardial sac endoscopically. RESULTS: All RGEAs were successfully harvested without injury. Harvest time averaged 29.9+/- 10.9 min. The harvested conduits averaged 24.7+/- 2.37 cm in length. Flows were excellent in all harvested conduits, averaging 81.1+/- 31.8 cc/min. The harmonic scalpel controlled all RGEA branches with excellent hemostasis. CONCLUSION: The RGEA can be harvested safely through port access with robotic assistance. This conduit is of sufficient length to be used as an alternative arterial conduit for totally endoscopic multivessel coronary artery bypass.

Hearing results after tympanoplasty in elderly patients with middle ear cholesteatoma.

Many reports about the effect of aging on hearing results after tympanoplasty have been published. However, they have not been evaluated comprehensively, i.e. by taking into consideration other aspects which also affect the outcome. In this study, the effect of aging on hearing results after canal wall reconstruction tympanoplasty was assessed in 236 consecutive ears of 213 patients > 20 years old with middle ear cholesteatoma. The elderly group (n = 34), defined as patients > or = 60 years old, was compared to the younger groups in terms of hearing results of postoperative hearing level, hearing gain, A-B gap and change in bone conduction hearing level at 4000 Hz after adjustment for age, gender, staged operation, preoperative hearing level and type of tympanoplasty, all of which affect hearing results, using the generalized linear regression method. Postoperative hearing level and hearing gain were found to be better amongst patients aged 20-29 and 30-39 years than in the elderly group, whilst A-B gap did not differ between all age categories. Within the elderly group, air conduction hearing level was shown to have improved after surgery. Changes in bone conduction hearing level at 4000 Hz were not significantly different between the age groups, suggesting that operative stress, i.e. mechanical stress or ossicular manipulation stress, does not aggravate sensorineural hearing loss in the elderly. We conclude that surgeons should be encouraged to perform tympanoplasty aimed not only at eradicating the lesion itself but also at improving hearing acuity in the elderly.

Troglitazone inhibits the expression of inducible nitric oxide synthase in adipocytes in vitro and in vivo study in 3T3-L1 cells and Otsuka Long-Evans Tokushima Fatty rats.

The aim of this study was to determine the mechanism of troglitazone action on nitric oxide (NO) production via inducible NO synthase (iNOS) in adipocytes in vitro and in vivo. The treatment of 3T3-L1 adipocytes with the combination of lipopolysaccharide (LPS), tumor necrosis factor-alpha and interferon-gamma synergistically induced de novo iNOS expression leading to enhanced NO production. The NO production was inhibited by co-treatment with aminoguanidine or N-nitro-L-arginine methylester hydrochloride. Troglitazone inhibited the NO production in a dose dependent manner by the suppression of iNOS expression. In the 24 week-old Otsuka Long-Evans Tokushima Fatty (OLETF) rats, the mean weight and the blood glucose were 21% and 30%, respectively, higher than in their lean counterparts. The serum nitrite concentration was increased after injection of LPS (4 mg/kg, i.p.), more markedly in OLETF rats than in the lean rats. The epididymal fats from LPS-injected groups, but not the ones from the non-injected groups, expressed mRNA and protein of iNOS. Troglitazone pre-treatment blocked the LPS-induced expression of iNOS in adipose tissue and the increase in serum nitrite concentration. These results suggest that troglitazone inhibits the cytokine-induced NO production in adipocytes by blocking iNOS expression both in vitro and in vivo.

Thromboembolism originated from the pulmonary artery stump after Fontan operation.

Cerebral thromboembolism is a rare but serious complication after Fontan operation. This is the report of a patient who underwent a successful intracardiac thrombectomy for cerebral thromboembolism after Fontan operation. A 2-year-old girl was referred to us with the diagnosis of tricuspid atresia without pulmonary stenosis, normally related great arteries, and a ventricular septal defect. Although she underwent a successful Fontan operation and division of the main pulmonary artery, she developed a cerebrovascular event at 3 weeks after the operation. Echocardiography demonstrated a large thrombus within the residue of the main pulmonary artery, and suggested that the thrombus had migrated into the systemic circulation by way of the ventricular septal defect. At 2 weeks after the cerebrovascular event, she underwent thrombectomy and excision of the pulmonary valve. Although she has developed slight left-sided hemiparesis, she is leading a normal life at 1 year after the operation.

Effect of a balanced biventricular bypass system on left ventricular energies.

Left dominant biventricular failure is a common type of heart failure after cardiac surgery. We developed a biventricular bypass (BVB) system for treatment of postcardiotomy ventricular failure, and we previously reported that the clinical results of the BVB system were superior to those obtained with venoarterial bypass (VAB). The purpose of this study was to evaluate the effect of the BVB system on left ventricular (LV) performance in comparison to that of VAB by means of the LV pressure-volume relationship (PVR). Eight adult mongrel dogs (14-21 kg) underwent VAB with right atrial and aortic cannulation. Left atrial cannulation was added for BVB, and both atrial drainage tubes were joined with a Y-shaped connector. The bypass flow was maintained at half of the baseline cardiac output (0.7-1.0 L/min), and the hemodynamic parameters were monitored. A high fidelity microtip catheter and a conductance catheter were used to evaluate LV function. The slope of the LV end-systolic pressure-volume relation (Emax), the slope of the LV end-systolic pressure-stroke-volume relation (Ea), the LV stroke work (SW), LV potential energy (PE), LV pressure-volume area (PVA), the slope of the SW end-diastolic volume relation (PRSW), and an index of the LV energizing charge (ratio of PE/PVA) were assessed during transient occlusion of the inferior vena cava. LV contractility (Emax) showed no significant change during each experiment. Standardized LV work (PRSW) was reduced by BVB in comparison to the baseline and in comparison to VAB. The rate of LV energy charge (PE/PVA) significantly increased only during BVB. These results suggested that the BVB system might be an effective circulatory support for reducing LV work and improving the LV energizing charge in patients with severe heart failure after cardiac operation.

[Stenosis of Carpentier-Edwards pericardial bioprosthesis in the tricuspid position caused by adhesion of native valve cusps to the bioprosthesis].

We experienced a case of dysfunction of Carpentier-Edwards pericardial bioprosthesis in the tricuspid position. Explanted bioprosthesis showed overgrowth of neointima from ring to cusps and adhesion to remnants of native cusps. This restricted the motion of the pericardial leaflets resulting in orifice stenosis. Care must be taken in such valve replacement by this prosthesis leaving native valve tissue.

[A case of anastomotic aneurysm-enteric fistula].

We successfully performed circulation reconstructive surgery and repair of a small intestine resection, primarily at an anatomical position, for perforation of a pseudoaneurysm in the small intestine, which occurred in an anastomosis site of the right leg of a Y graft of an artificial blood vessel and internal iliac artery graft on a patient, at the remote time of 18 years after she had received a Y-type artificial blood vessel. The patient's life was saved. The results suggest that it is important to make a definitive diagnosis quickly after the occurrence of symptoms and to select an appropriate surgical technique according to the findings of infection adjacent to the perforation site.

[A case report on graft replacement of ruptured aneurysm of the arch and the descending thoracic aorta associated with dense pulmonary adhesion].

A 73-year-old patient had been followed for aortic arch aneurysm of 54 mm in diameter. He was hospitalized complaining of chest and back pain. A chest CT scan showed ruptured aortic arch aneurysm extending to mid-descending thoracic aorta, and an emergent operation was decided. The trachea was intubated with a univent tube providing a movable blocker (System Corporation) which was directed to the left bronchus for differential lung ventilation. The descending thoracic aorta was exposed through the left 4th intercostal thoracotomy just at the site intending to anastomose a prosthetic graft because of dense pulmonary adhesion. The ascending and arch aorta was approached via median sternotomy. Under deep hypothermia and retrograde cerebral perfusion, total arch and descending aortic replacement was performed using an arch graft providing four branch grafts for neck vessels reconstruction and pump perfusion. The patient showed moderate pulmonary bleeding during and after cardiopulmonary bypass, but improved gradually. He was weaned from the respirator on the 13th post-operative day. During extensive thoracic aortic surgery using left thoracotomy combined with median sternotomy, left lung deflation using a univent tracheal tube with a blocker, and circulatory arrest during distal aortic anastomosis, are useful in preventing lethal pulmonary bleeding caused by lung injury under the fully heparinized condition. However, in cases associated with dense pulmonary adhesion, it is important to dissect carefully just a small area necessary to anastomose a graft, and to take elaborate assistant measures.

[Use of an expandable metallic stent in patients with superior vena cava syndrome--comparison of angiographic findings and autopsy findings].

To evaluate the usefulness of expandable metallic stens (EMS) in patients with superior vena cava (SVC) syndrome, we compared venographic findings obtained before EMS insertion with findings at autopsy. Stents were inserted into the SVC in 10 patients. An autopsy was done in 7 of the 10 patients. At autopsy, the lumen of the SVC was patent in 4 patients; in those 4 patients venography before EMS insertion showed that the SVC was obstructed by extramural compression. These results suggest that extramural compression without direct invasion of the tumor is the best indication for insertion of an EMS. At autopsy, the lumen of the SVC was obstructed by direct invasion of a tumor in 2 patients; in those 2 patients venography showed wall irregularity and lumen narrowing caused by tumor invasion. However, in those 1 patients SVC syndrome either did not recur or recurred in only a mild form after EMS insertion. The results in these 2 patients suggest that if collateral circulation does not develop, insertion of an EMS is indicated also in patients in whom the SVC is obstructed by direct invasion of a tumor. In the remaining patient, the lumen of the SVC was found at autopsy to be obstructed by a thrombus. SVC syndrome developed in this patient 430 days after EMS insertion. In 1 of the 7 patients, an EMS was inserted into the left innominate vein and also into the SVC. Venography before EMS insertion showed that the vein was obstructed by extramural compression without direct invasion of the tumor, but the EMS was found at autopsy to be completely obstructed by a thrombus. This suggests that insertion of an EMS into the left innominate vein is not indicated this vein is easily obstructed by thrombi because of its anatomical location.

[Repeat open heart surgery in a case associated with persistent left superior vena cava: a method of simple occlusion of L-SVC using an alternative extra-pericardial approach and retrograde cardioplegia].

Twelve years ago, we reported a method of extrapericardial approach to the L-SVC. Since then we have used this approach and performed simple occlusion of L-SVC during cardiopulmonary bypass without any cerebral complications. We have been expecting for a long time and have believed that this method will be very valuable especially in repeat open heart surgery. A case of 49-year-old man successfully underwent a redo operation for mitral and tricuspid valve replacement using extrapericardial occlusion of the L-SVC and retrograde cardioplegia. Although there was a pitfall for retrograde cardioplegia in the persistent L-SVC and a possibility of steal of cardioplegic fluid through a branch of the accessory hemiazygos vein during retrograde cardioplegia for a case with persistent L-SVC, sufficient cardiac protection was obtained in the case presented.

[A case of Von Recklinghausen's disease associated with a hemothorax due to a rapidly growing malignant schwannoma].

A 17-year-old man with Von Recklinghausen's disease was admitted to our hospital because of progressive dyspnea on exertion. A chest X-ray film showed a massive left pleural effusion. Thoracentesis revealed dark blood. Hemothorax was diagnosed, and digital subtraction angiography (DSA) was done. DSA revealed a large mass that was supplied with blood via the inferior phrenic artery, but revealed no active bleeding. An intercostal tube was inserted and 1700 ml of dark blood was drained. A chest X-ray film taken after drainage revealed a giant mass showing an extra-pleural sign in the left lung field. A thoracotomy was done to determine the source of bleeding. A giant tumor with hypervascular tissue was seen, and was diagnosed as a malignant schwannoma. No spontaneous hemorrhage from the artery was seen. The source of the hemothorax was believed to be hemorrhage from the tumor vessels. The tumor was treated conservatively, but it continued to grow rapidly and the patient died of respiratory failure. Five other patients have been reported to have hemothorax associated with Von Recklinghausen's disease. The sources of the hemothorax were reported to be hemorrhage from tumor vessels, or spontaneous rupture of the subclavian artery, an intercostal artery, or an intercostal vein.