PPARgamma agonists inhibit cell growth and suppress the expression of cyclin D1 and EGF-like growth factors in ras-transformed rat intestinal epithelial cells

Peroxisome proliferator-activated receptor gamma (PPARgamma) inhibits the growth of several types of cancer cells. However, the mechanisms by which this occurs are poorly understood. The goal of the present study was to investigate the effects of PPARgamma on mutated ras-induced cell growth, activation of transcription factors and expression of genes associated with cellular transformation in rat intestinal epithelial cells. A human PPARgamma cDNA was introduced to the activated H-ras-transfected IEC-6 cells (IECras) and 1 clone (IECrasPR82) that stably expresses both activated ras and PPARgamma was obtained. Thiazolidinedione derivatives such as troglitazone and rosiglitazone, selective ligands for PPARgamma, inhibited the cellular growth of IECrasPR82 cells in a time-dependent manner and induced G1 cell cycle arrest. Treatment with troglitazone (20 microM) decreased the expression of cyclin D1, heparin-binding epidermal growth factor-like growth factor (HB-EGF) and amphiregulin and suppressed the promoter activities of cyclin D1 and HB-EGF. Furthermore, a luciferase assay and an electrophoretic mobility shift assay showed that thiazolidinedione derivatives suppressed the transcriptional activities of AP-1 and Ets, both of which play crucial roles in the expression of cyclin D1 and HB-EGF. These findings suggest that reduction of EGF-like growth factors and cyclin D1 through the suppression of AP-1 and Ets may be 1 mechanism whereby PPARgamma inhibits their growth.

[Two pediatric cases of malignant hyperthermia caused by sevoflurane]

We experienced two cases of malignant hyperthermia (MH) triggered by sevoflurane. Case 1 was a six-year-old girl, 15.8 kg, undergoing strabismus repair. She had flat back, elevated diaphragm and high arched palate. Anesthesia was induced and maintained with sevoflurane and nitrous oxide in oxygen. Her trachea was intubated without the use of muscle relaxant. Thirty minutes after the induction of anesthesia, ETco2 was over 60 mmHg despite hyperventilation. Muscle rigidity of legs and the rise in temperature were noted. MH was diagnosed and dantrolene i.v. was administered. Her maximum esophageal temperature was 40.2 degrees C. ETco2 and temperature returned to baseline values after dantrolene administration. Creatine phosphokinase (CK) level was 252 U.l-1 preoperatively, and 1690 U.l-1 next day. Case 2 was a year-and-9-month-old boy undergoing accessory ear resection. Anesthesia was induced with sevoflurane and nitrous oxide in oxygen. His trachea was intubated with an aid of vecuronium. Forty minutes after administration of sevoflurane his temperature rose to 38.6 degrees C with heart rate 191 bpm and Spo2 93%, and muscle rigidity of legs. MH was diagnosed and dantrolene was administered. His highest temperature was 39.3 degrees C and was reduced promptly after dantrolene. Postoperatively he was noted to have downslanting palpebral fissures, micrognathia, low set ears, and a single crease of the fifth finger and diagnosed as King syndrome which is reported to have association with MH. Both patients had no history of anesthesia nor abnormal family history. Both of them were rescued with dantrolene and recovered without sequelae.

Enzymatic and non-enzymatic reduction of brucine N-oxide by aldehyde oxidase and catalase

1. Brucine N-oxide was reduced by aldehyde oxidase in rabbit liver cytosol in the presence of an electron donor, 2-hydroxypyrimidine, under anaerobic conditions. The flavoprotein purified from rabbit liver exhibited significant reductase activity in the presence of electron donors. 2. Brucine N-oxide was also reduced by rabbit liver cytosol and blood in the presence of both a reduced pyridine nucleotide and FAD under anaerobic conditions. The N-oxide reductase activities were inhibited by carbon monoxide and air. However, these activities were not abolished whe n liver cytosol and blood were boiled. Rabbit erythrocytes exhibited the reductase activity, but not plasma. 3. When liver cytosol or blood was separated by DEAE-cellulose column chromatography, the fractions with the reducing activity in the presence of both NADH and FAD also showed catalase activity. 4. Catalase catalysed the brucine N-oxide reduction in the presence of both NAD(P)H and FAD. Hematin also exhibited the reductase activity in the presence of both NAD(P)H and FAD. Photochemically reduced FAD was effective in the reduction instead of NAD(P)H and FAD. 5. Bricine N-oxide reduction proceeds via two routes in liver cytosol and blood. One is enzymatic reduction by aldehyde oxidase; the other is non-enzymatic reduction catalysed by the haem group of catalase in the presence of reduced flavin.

Redo operation for thoracoaortic aneurysm after entire aortic replacement

Resection of a saccular aneurysm that developed in a remnant of aorta in a patient with Marfan's syndrome, who previously underwent aortic aneurysmectomy, is described. The intercostal arteries were reconstructed end-to-end using small-caliber interposition grafts to the aortic prosthesis. Preoperative magnetic resonance angiography identified the artery of Adamkiewicz and facilitated its preservation.

Blood supply to the duodenal papilla and the communicating artery between the anterior and posterior pancreaticoduodenal arterial arcades

The communicating artery (ComA) between the anterior and posterior pancreaticoduodenal arterial arcades is little understood, although it has been described several times during the past 100 years. In 44 of 51 cadaveric specimens in the present study, the typical ComA was observed to pass between the major and accessory pancreatic ducts. In addition, a second ComA was sometimes found crossing inferior to the major pancreatic duct. The typical ComAs often (36 of the 44) issued papillary branch(es). Although direct papillary branches of the posterior arcade were often observed to either coexist with (9 specimens) or exist independently (4 specimens), the ComA-derived branch seemed to be critical for papillary blood supply, because of its shorter length, greater thickness, and higher frequency. Moreover, the typical ComA could be a good landmark during limited pancreatic resection, such as duodenum-preserving subtotal resection of the pancreatic head or pancreatic segment resection, because the artery is likely to be an indicator of the borders between the celiac and superior mesenteric arterial territories, as well as those between the ventral and dorsal segments of the pancreas.

A new hysteroscopic tubal embryo transfer catheter: development and clinical application

OBJECTIVE

Development and clinical application of a new hysteroscopic tubal embryo transfer catheter.

METHOD

Catheterization was performed in 60 patients at hysteroscopic insemination into tube, using 3 French catheters, in which the distal 3, 4, and 5 cm tapered to 2 French. Hysteroscopic tubal embryo transfer and conventional IVE-ET were performed in 30 patients with normal tubes, who failed to achieve pregnancy after 2 IVF-ET trials.

RESULT

The success rate of complete insertion with the catheter tapering at the distal 3 cm was significantly higher than that at the distal 5 cm. Since we obtained the highest success rate of insertion with the catheter tapering at the distal 3 cm, we selected this catheter for the h-TEST. The rate of pregnancy in h-TEST was significantly higher than that in conventional ET.

CONCLUSION

The h-TEST using our catheter was useful for establishing pregnancy in assisted reproduction.

Modification of bicaval anastomosis technique for orthotopic heart transplantation

A modified bicaval anastomosis technique was utilized for 4 consecutive patients undergoing heart transplantation. Instead of transecting the superior and inferior vena cavae, a strip of the posterior right atrial wall was left undivided as a bridge connecting the superior and inferior vena cavae. This minor modification perfectly prevented shrinkage and retraction of the caval tissue, thus providing easier anastomotic orientation and better estimation of the appropriate tissue length that fits well, particularly when a small donor heart was available.

[Endoscopic mucosal resection for early gastric carcinoma]

Endoscopic mucosal resection (EMR) has made it possible to perform radical resection of early gastric cancers in resectable cases. To extend the indications for EMR, we discuss the following. 1) Three hundred fifty-seven patients with 389 lesions of early gastric cancer who were treated either with whole-block resection or partial resection were analyzed to evaluate the recurrence rate by the method. The recurrence rate was 15.1% of 139 lesions treated with whole-block resection and 8.0% of 250 lesions treated with both methods. It is considered that partial resection with the marking procedure is very important to remove the cancer completely. 2) The management of recurrent cancer recognized at follow-up examination after EMR is very important for patients because these are operable cases. Of recurrent cancers, 80.5% were diagnosed within one year after EMR, and therefore during this period careful follow-up examinations should be done. The therapy used to treat these recurrent cancers was re-EMR in 26 cases and surgical operation in 15 cases. 3) Problems still remain concerning how to manage cancer invading the submucosa diagnosed after EMR.

[An extremely low birth weight infant with pulmonary atresia complicated with necrotizing enterocolitis]

We experienced an extremely low birth weight (ELBW) infant complicated with pulmonary atresia and necrotizing enterocolitis. She was born at 25 weeks of gestation with a birth weight of 752 g. Five hours after birth, she manifested cyanosis and was diagnosed as having pulmonary atresia with intact ventricular septum (PAIVS). Infusion of lipo-prostaglandin E1 (PGE1) was started to keep the ductus open along with infusion of dopamine and dobutamine. At 8 days of life she developed hypotension and metabolic acidosis, and the diagnosis of intestinal perforation was made by free air in the abdomen. The excessive shunt flow to the pulmonary vasculature via the ductus was suspected to have caused an inadequate systemic flow leading to the intestinal ischemia and necrotizing enterocolitis. Lipo-PGE1 was discontinued to decrease the shunt flow through the ductus. Brock's operation (closed transventricular pulmonary valvotomy) was performed at the age of 8 and 11 days and the ligation of the ductus arteriosus was performed at the age of 13 days. Propranolol was administered to inhibit the pulmonary outflow tract constriction along with catecholamines to stabilize hemodynamics. She recovered slowly and her trachea was extubated at 58 days of life.

A morphologic study of Carpentier-Edwards pericardial xenografts in the mitral position exhibiting primary tissue failure in adults in comparison with Ionescu-Shiley pericardial xenografts

OBJECTIVE

We sought to investigate the durability and mechanism of the Carpentier-Edwards pericardial xenograft in the mitral position in comparison with that of the Ionescu-Shiley pericardial xenograft.

METHODS

A total of 284 patients who received the Ionescu-Shiley pericardial xenograft in the mitral position between 1980 and 1984 and 84 patients who received the Carpentier-Edwards pericardial xenograft in the mitral position between 1984 and 1999 were included in the study. The freedom from reoperation rates for both graft types were determined. For morphologic study, the pathologic findings of 23 valves of 123 explanted Ionescu-Shiley pericardial xenografts with structural valve deterioration, nonstructural valve deterioration, or both were determined and compared with those of 20 explanted Carpentier-Edwards pericardial xenografts with structural valve deterioration, nonstructural valve deterioration, or both. Each pathologic finding was graded and assigned a score. Both types were matched for age at reoperation (50-75 years) and duration of valve function (8-11 years).

RESULTS

Freedom from reoperation caused by structural valve deterioration, nonstructural valve deterioration, or both was significantly better for Carpentier-Edwards pericardial xenografts than for Ionescu-Shiley pericardial xenografts at 8 years after the operation (Carpentier-Edwards pericardial xenografts: 91.3% vs Ionescu-Shiley pericardial xenografts: 71.9%, P =.0061), but it was similar for both types at 12 years (Carpentier-Edwards pericardial xenografts: 43.6% vs Ionescu-Shiley pericardial xenografts: 43.6%, P =.2865). No severe leaflet tears were seen among Carpentier-Edwards pericardial xenografts. The mean area percentage of tissue overgrowth was 15.3% in Carpentier-Edwards pericardial xenografts and 3.4% in Ionescu-Shiley pericardial xenografts (P =.0001). The mean calcification area percentage was 13.6% in Carpentier-Edwards pericardial xenografts and 31.5% in Ionescu-Shiley pericardial xenografts (P =.0001).

CONCLUSIONS

Tissue overgrowth on the atrial surface, ventricular surface, or both was the cause of structural valve deterioration, nonstructural valve deterioration, or both of Carpentier-Edwards pericardial xenografts in adults. This was different from Ionescu-Shiley pericardial xenograft failure, which resulted from severe calcification and leaflet tears. Organized thrombi on cusps, in addition to valve design, may have contributed to such tissue overgrowth on Carpentier-Edwards pericardial xenografts.

Applications of fluorescence microscopy to studies of dental hard tissue

In this review we describe applications of fluorescence microscopy to investigations of dental hard tissue. Many studies have shown that human teeth show autofluorescence and several applications of fluorescence microscopy have been reported, although the chemical nature of autofluorescence remains unknown. However, most applications are based on a static measurement mode, which has inherent limitations. These limitations can be overcome by the use of time-resolved fluorescence microscopy. Therefore, we attempted to combine ordinary and time-resolved fluorescence microscopy to study human dentine. Using stationary measurements, blue fluorescence with a peak of 440 +/- 10 nm and a width of approximately 100 nm was observed. Increases in fluorescence intensity were found to be dependent upon age and temperature, regardless of tooth type or gender. The results suggest that the aging mechanism for crown dentine differs from that for root dentine and that the observed increase in fluorescence intensity is partially due to a temperature-dependent physicochemical mechanism. We speculate that fluorescence microscopy will become a useful tool for analysis of dental hard tissue in several fields.

Activation of rho is involved in the mechanism of hydrogen-peroxide-induced lung edema in isolated perfused rabbit lung

Acute lung injury is attributed primarily to increased vascular permeability caused by reactive oxygen species derived from neutrophils, such as hydrogen peroxide (H2O2). Increased permeability is accompanied by the contraction and cytoskeleton reorganization of endothelial cells, resulting in intercellular gap formation. The Rho family of Ras-like GTPases is implicated in the regulation of the cytoskeleton and cell contraction. We examined the role of Rho in H2O2-induced pulmonary edema with the use of isolated perfused rabbit lungs. To our knowledge, this is the first study to examine the role of Rho in increased vascular permeability induced by H2O2 in perfused lungs. Vascular permeability was evaluated on the basis of the capillary filtration coefficient (Kfc, ml/min/cm H2O/100 g). We found that H2O2 (300 microM) increased lung weight, Kfc, and pulmonary capillary pressure. These effects of H2O2 were abolished by treatment with Y-27632 (50 microM), an inhibitor of the Rho effector p160 ROCK. In contrast, the muscular relaxant papaverine inhibited the H2O2-induced rise in pulmonary capillary pressure, but did not suppress the increases in lung weight and Kfc. These findings indicate that H2O2 causes pulmonary edema by elevating hydrostatic pressure and increasing vascular permeability. Y-27632 inhibited the formation of pulmonary edema by blocking both of these H2O2-induced effects. Our results suggest that Rho-related pathways have a part in the mechanism of H2O2-induced pulmonary edema.

Gastrin induces CXC chemokine expression in gastric epithelial cells through activation of NF-kappaB

Although hypergastrinemia is frequently observed in individuals with a chronic Helicobacter pylori infection, its pathophysiological significance in gastric mucosal inflammation is unclear. The present study was designed to determine if gastrin induces the expression of CXC chemokines in gastric epithelial cells. Human and rat gastric epithelial cells, transfected with gastrin receptor, were stimulated with gastrin. The expression of mRNAs for human interleukin-8 (IL-8) and rat cytokine-induced neutrophil chemoattractant-1 and release of human IL-8 protein were then determined by Northern blot analysis and ELISA, respectively. Gastrin not only induced the expression of mRNAs for these chemokines but also stimulated IL-8 protein release. A luciferase assay using IL-8 promoter genes showed that nuclear factor (NF)-kappaB is absolutely required and activator protein-1 (AP-1) is partly required for the maximum induction of IL-8 by gastrin. An electrophoretic mobility shift assay revealed that gastrin is capable of activating both NF-kappaB and AP-1. In addition, the inhibition of NF-kappaB abrogated gastrin-induced chemokine expression. These results suggest that gastrin is capable of upregulating CXC chemokines in gastric epithelial cells and therefore may contribute to the progression of the inflammatory process in the stomach.

Continuous systemic perfusion improves outcome in one stage repair of obstructed aortic arch and associated cardiac malformation

OBJECTIVE

To determine whether continuous systemic perfusion is of effective use when establishing primary repair of the aortic obstruction and associated cardiac malformations.

METHODS

Since 1991, 56 infants have undergone reconstruction of interrupted (in 28) or coarctated (in 28) aorta, concomitantly with closure of ventricular septal defects in 37, and repair of other malformations in the remaining 19. Of these, total circulatory arrest (30+/-11 min) was employed in 23. In another 21 patients, perfusion was maintained for the carotid arteries with the descending aorta cross-clamped (31+/-15 min). The bodily organs were perfused throughout the operative procedures by placing dual aortic cannulae in the remaining 12 patients.

RESULTS

The postoperative courses were less eventful in the non-circulatory arrest group than other groups of patients undergoing total or partial circulatory arrest, although these groups were operated in different time periods, and consequently, a general progress might be one reason for improvements in the surgical outcomes. All patients undergoing no circulatory arrest survived the primary repair, could have the sternum primarily closed, and had no episodes of cerebral bleeding. Prolonged tracheal intubation was needed just in one patient of this group. The amount of urine output during cardiopulmonary bypass was significantly greater in the non-circulatory arrest group than in the others. The maximal concentrations of urinary beta-microglobulin, serous creatinine, creatine phosphokinase, and glutamic oxaloacetic transaminase were lower in this setting.

CONCLUSIONS

Continuous systemic perfusion was considered less invasive when concomitantly repairing the obstructed aorta and intracardiac malformations.

Pericardiectomy for constrictive pericarditis using the harmonic scalpel

A 35-year-old man with constrictive pericarditis underwent pericardiectomy. The pericardium was dissected with a Harmonic Scalpel (Ethicon Endo-Surgery, Cincinnati, OH). This new device has many advantages including no muscular stimulation, low heat, a smokeless field, and easy hemostasis. The Harmonic Scalpel is beneficial for dissection of thickened pericardium.

Rat cardiac contractile dysfunction induced by Ca2+ overload: possible link to the proteolysis of alpha-fodrin

The aim of the present study was to examine the mechanisms of Ca2+ overload-induced contractile dysfunction in rat hearts independent of ischemia and acidosis. Experiments were performed on 30 excised cross-circulated rat heart preparations. After hearts were exposed to high Ca2+, there was a contractile failure associated with a parallel downward shift of the linear relation between myocardial O(2) consumption per beat and systolic pressure-volume area (index of a total mechanical energy per beat) in left ventricles from all seven hearts that underwent the protocol. This result suggested a decrease in O(2) consumption for total Ca2+ handling in excitation-contraction coupling. In the hearts that underwent the high Ca2+ protocol and had contractile failure, we found marked proteolysis of a cytoskeleton protein, alpha-fodrin, whereas other proteins were unaffected. A calpain inhibitor suppressed the contractile failure by high Ca2+, the decrease in O(2) consumption for total Ca2+ handling, and membrane alpha-fodrin degradation. We conclude that the exposure to high Ca2+ may induce contractile dysfunction possibly by suppressing total Ca2+ handling in excitation-contraction coupling and degradation of membrane alpha-fodrin via activation of calpain.

Potent dibasic GPIIb/IIIa antagonists with reduced prolongation of bleeding time: synthesis and pharmacological evaluation of 2-oxopiperazine derivatives

A series of 2-oxopiperazine derivatives, possessing basic moieties at the 3- and the 4-positions, were synthesized and evaluated for their abilities to inhibit platelet aggregation and for their effects on bleeding time. Among the compounds, 2-[(3S)-4-[2-[(4-guanidinobenzoyl)amino]acetyl]-3-[3-[(4-guanidinobenzoyl)amino]propyl]-2-oxopiperazinyl]acetic acid (12c) showed a potent inhibitory effect on platelet aggregation and good dissociation between the efficacy and the bleeding side effect. Intravenous infusion of compound 12c at 1.6 microg/mL/min completely prevented arterial thrombus formation induced by endothelial injury in guinea pigs. The dose of 12c that prolonged the bleeding time to three times the control value was 5.8 microg/mL/min. These results suggest that compound 12c might be useful in the clinical treatment of thrombotic diseases, and we selected 12c (TAK-024) as a candidate for the clinical trials.

Contribution of central amiloride-sensitive transport systems to the development of hypertension in spontaneously hypertensive rats

This study was conducted to examine if central amiloride-sensitive transport systems are involved in the development and/or maintenance of hypertension in spontaneously hypertensive rats (SHR). Either amiloride (75 microg/60 microl/day) or artificial cerebrospinal fluid (aCSF, 60 microl/day) was infused centrally (i.c.v.) for 4 weeks to development (4-5-weeks-old) and maintenance (10-12-weeks-old) phases of hypertension in SHR. In development phase, amiloride i.c.v. (n=14) blunted the elevation of blood pressure (BP) compared to aCSF i.c.v. (n=9) (amiloride vs. aCSF; after 3 weeks of i.c.v., 146+/-3 vs. 166+/-5 mmHg, P<0.001). The difference of BP at 3 weeks of i.c.v. was canceled after ganglionic block with hexamethonium (115+/-4 vs. 117+/-5 mmHg). Further, pressor responsiveness to norepinephrine was augmented in amiloride i.c.v. rats (amiloride, n=11 vs. aCSF, n=6; %Delta BP at 800 ng/kg/min.: 16.9+/-1.3 vs. 10.8+/-1.4 mmHg, P<0.05) and this augmentation disappeared after ganglionic block. Pressor responsiveness to angiotensin II and cumulative sodium balance did not differ in the two groups. Intravenous administration of amiloride at the same dose did not attenuate the development of hypertension. On the other hand, in maintenance phase, amiloride i.c.v. by the same protocol as in development phase had no effect on BP in SHR. Also, amiloride i.c.v. did not affect BP in normotensive Wistar-Kyoto rats. These results suggest that central amiloride-sensitive transport systems are involved in the development, but not in the maintenance, of hypertension in SHR through the modulation of autonomic neural mechanisms.

Effects of photoperiod on pituitary gonadotropin levels in masu salmon

We examined the effects of photoperiod on pituitary levels of two types of gonadotropin (GTH), GTH I and GTH II, in masu salmon Oncorhynchus masou to study their mechanism of synthesis. In Experiment 1, the effects of long or short photoperiod combined with castration were examined using 8-month-old precocious males. Castration was carried out in early August and then the fish were reared under a short (8L16D) or long (16L8D) photoperiod for 60 days. In Experiment 2, the effects of photoperiod combined with testosterone treatment were examined using 12-month-old immature females. Silastic tubes containing testosterone (500 microg /fish) or vehicle were implanted intra-peritoneally in early October. Fish were reared under 16L8D for 60 days, and then half of the fish were transferred to 8L16D, while the remaining fish were kept under 16L8D until Day 90. In Experiment 1, GTH I contents were higher under 16L8D than under 8L16D in the castrated group on Day 30. Moreover, GTH I contents were higher in the castrated group than the control group under 16L8D on Day 30. GTH II contents increased with testicular maturation in the control groups, whereas they remained at low levels in the castrated groups regardless of photoperiodic treatment. In Experiment 2, GTH I contents did not change remarkably in all the groups, while GTH II contents were remarkably increased by testosterone treatment regardless of photoperiodic treatment. These results indicate that the synthesis of GTH I and GTH II are differently regulated by photoperiod and testosterone in masu salmon.

Prospective comparative study of brain protection in total aortic arch replacement: deep hypothermic circulatory arrest with retrograde cerebral perfusion or selective antegrade cerebral perfusion

BACKGROUND

The purpose of this study was to compare the results of total aortic arch replacement using two different methods of brain protection, particularly with respect to neurologic outcome.

METHODS

From June 1997, 60 consecutive patients who underwent total arch replacement through a midsternotomy were alternately allocated to one of two methods of brain protection: deep hypothermic circulatory arrest with retrograde cerebral perfusion (RCP: 30 patients) or with selective antegrade cerebral perfusion (SCP: 30 patients). Preoperative and postoperative (3 weeks) brain CT scan, neurological examination, and cognitive function tests were performed. Serum 100b protein was assayed before and after the cardiopulmonary bypass, as well as 24 hours and 48 hours after the operation.

RESULTS

Hospital mortality occurred in 2 patients in the RCP group (6.6%) and 2 in the SCP group (6.6%). New strokes occurred in 1 (3.3%) of the RCP group and in 2 (6.6%) of the SCP group (p = 0.6). The incidence of transient brain dysfunction was significantly higher in the RCP group than in the SCP group (10, 33.3% vs 4, 13.3%, p = 0.05). Except in patients with strokes, S-100b values showed no significant differences in the two groups (RCP: SCP, prebypass 0.01+/-0.04: 0.05+/-0.16, postbypass 2.17+/-0.94: 1.97+/-1.00, 24 hours 0.61+/-0.36: 0.60+/-0.37, 48 hours 0.36+/-0.45: 0.46+/-0.40 microg/L, p = 0.7). There were no intergroup differences in the scores of memory decline (RCP 0.74+/-0.99; SCP 0.55+/-1.19, p = 0.6), orientation (RCP 1.11+/-1.29; SCP 0.50+/-0.76, p = 0.08), or intellectual function (RCP 1.21+/-1.27; SCP 1.05+/-1.15, p = 0.7).

CONCLUSIONS

Both methods of brain protection for patients undergoing total arch replacement resulted in acceptable levels of mortality and morbidity. However, the prevalence of transient brain dysfunction was significantly higher in patients with the RCP.

[Reconstruction of the right ventricular outflow tract in patients undergoing the Ross procedure]

Since 1992, 46 patients have undergone the Ross procedure. Of these, a pulmonary homograft was used for reconstruction of the RVOT in 16, and a tailored heterologous or autologous pericardial roll tube in 9. In the remaining 21, the autologous tissues were used as a posterior wall of the channel, placing another patch (bearing a monocusp in 14) anteriorly. All the patients survived the procedure. Reoperation has been needed thus far in one for infection of the prosthetic patch placed at the right ventricular outflow tract, and catheter intervention in 2 for mild obstruction across the channel. On the basis of postoperative catheterization, presence or absence of a valvar structure across the right ventricular outflow tract did not affect ejection fraction of the right ventricle and right atrial pressure. In contrast, right ventricular end diastolic volume was smaller, as well as diastolic pulmonary arterial pressure was higher, when a competent trifoliate valve was provided at the right ventricular outflow tract. An incision to the ventricular septum for subaortic stenosis, coronary arterial obstruction preoperatively present, and age at operation younger than 2 years old, were unfavourable factors affecting right ventricular performance. We conclude that, in the majority of our patients, right ventricular performance was unlikely impaired even without a competent pulmonary valve. Use of a homograft, however, could be preferred in a selected group of patients with deleterious circumstances on the postoperative circulation.

Extremely high drug-reductase activity based on aldehyde oxidase in monkey liver

Drug-reducing ability of monkey liver cytosol was examined in this study. Monkey liver cytosol exhibited significant reductase activities toward zonisamide, sulindac and imipramine N-oxide in the presence of 2-hydroxypyrimidine or benzaldehyde, an electron donor to aldehyde oxidase. These activities were abolished by inhibitors of aldehyde oxidase, such as menadione. These reductase activities in monkeys were extremely high compared to those in other animals. The zonisamide reductase activity of monkey liver cytosol was about 40-fold higher than that of the liver microsomes. It appears that the high levels of aldehyde oxidase exists in monkey liver, and zonisamide, sulindac and imipramine N-oxide are mainly reduced by this enzyme, not by cytochrome P450.

Congenital diverticulum of the left ventricle

We present a case of a congenital left ventricular diverticulum of fibrous type that was surgically repaired. Considering the potential risks such as rupture, systemic thromboembolism, and arrhythmia, an early surgical intervention should be employed for this rare abnormality even in a child without clinical symptoms.

The involvement of sex steroid hormones in downstream and upstream migratory behavior of masu salmon

From May through July when masu salmon, Oncorhynchus masou, commence downstream migration under natural conditions, yearling precocious male masu salmon (resident form) showed higher GSI and plasma levels of testosterone (T) and 11-ketotestosterone (11-KT) in contrast to immature smolts (migratory form). From March through September coinciding with the upstream migration period, 2-year-old male and female adults also showed higher GSI and plasma levels of T, estradiol-17beta (E(2)) 11-KT, 17alpha-hydroxyprogesterone and 17alpha,20beta-dihydroxy-4-pregnene-3-one (DHP). In order to test the effects of steroid hormones on migratory behaviors, silascone tube capsules containing 500 microg of T, E(2), 11-KT, DHP, or a vehicle was implanted into smolts, castrated precocious males, or immature parr, and downstream and upstream behavior were observed in artificial raceways in spring and autumn. Downstream behavior of smolts was inhibited significantly by T, E(2) and 11-KT. Upstream behavior was stimulated by T and 11-KT in castrated precocious males and stimulated by T, E(2) and 11-KT in immature parr. These results indicate that T, E(2) and 11-KT are the factors regulating downstream and upstream migratory behavior. In particular, because of its changing patterns in plasma and significant effects, T, the common precursor hormone of E(2) (female) and 11-KT (male), is considered to play central roles in both types of behavior.