[Surgical treatment for aortic root dilatation and aortic regurgitation after arterial switch operation].

Aortic regurgitation (AR) and, aortic root dilatation are serious problems occurring after arterial switch operation (ASO). We have experienced a case of 12-year-old boy with aortic root dilatation and AR after ASO. Consistent progression of AR and aortic root dilatation were observed during the follow-up period. The latest Z-score of Valsalva sinus was about 9. We performed the Bentall procedure instead of aortic valve-sparing operation because of the degenerative aortic valve and the excessive aortic root dilatation. The postoperative course was uneventful. Histopathological findings of the aortic wall showed degeneration of elastic fibers on both sides of the anastmosis.

[Primary cardiac angiosarcoma in the left atrium with adrenal metastasis; report of a case].

We encountered a 61-year-old woman with primary cardiac angiosarcoma in the left atrium. On echocardiography, the tumor extended into the atrial septum and mitral valve, and mitral valve stenosis and regurgitation were significant. We resected the tumor protruding into left atrium, and affecting mitral valve. The surgical procedure was not radical, but on postoperative echocardiography, function of the mitral valve was improved. Three months later, elevation of her right diaphragma was observed on chest X-ray and a giant adrenal tumor was detected by magnetic resonance imaging. Tumor biopsy indicated that this tumor was adrenal metastasis from cardiac angiosarcoma. In addition, echocardiography showed the recurrence of angiosarcoma in the left atrium and the presence of mitral stenosis and regurgitation. She died of heart failure 185 days postoperatively.

Occurrence of ribitol-containing lipoteichoic acid in Staphylococcus aureus H and its glycosylation.

A ribitol-containing lipoteichoic acid was obtained from the 20,000 x g supernatant fraction of Staphylococcus aureus H by extraction with Triton X-100 followed by fractionation on Sepharose 6B and DEAE-cellulose columns. The purified lipoteichoic acid was composed of phosphate, glycerol, glucose, glucosamine, ribitol, and fatty acids in a molar ratio of 1 : 0.9 : 0.06 : 0.03 : 0.09 : 0.07. Based on the structural analysis of fragments from alkali and HF hydrolysis, the lipoteichoic acid appears to consist of three moieties, namely a ribitol phosphate oligomer, poly(glycerol phosphate) which has about 30 glycerol phosphate units, and beta-glucosyl-beta-glucosyl(1 leads to 1)diacylglycerol. N-Acetylglucosamine was linked to the ribitol residues. The lipoteichoic acid serves as an acceptor of glycosyl moieties from UDP-glucose and UDP-N-acetylglucosamine in the enzyme reaction catalyzed by the membrane preparation. The rate of enzymatic glycosylation was increased by prior treatment of the lipoteichoic acid with N-acetyl-beta-D-glucosaminidase. The glycosylation seems to occur at the ribitol residues of the lipoteichoic acid.

Biosynthesis of UDP-N-acetyl-D-glucosaminuronic acid and UDP-N-acetyl-D-mannosaminuronic acid in Micrococcus luteus.

The occurrence and formation of UDP-N-acetyl-D-glucosaminuronic acid (UDP-GlcNAcA) and UDP-N-acetyl-D-mannosaminuronic acid (UDP-ManNAcA) were studied in Micrococcus luteus ATCC 4698. UDP-N-acetylhexosaminuronic acid separated from D-cycloserine-inhibited cells was shown to be a mixture of UDP-GlcNAcA and UDP-ManNAcA in the ratio of 87:13, whereas that obtained from untreated cells was a 96:4 mixture of these two nucleotides. Crude enzyme preparations obtained from the supernatant fraction of cells catalyzed the NAD+-dependent conversion of UDP-GlcNAc into UDP-GlcNAcA and UDP-ManNAcA. Studies on the partial separation and properties of enzymes revealed that UDP-GlcNAcA is synthesized directly from UDP-GlcNAc by the action of UDP-GlcNAc dehydrogenase and that UDP-ManNAcA is synthesized from UDP-GlcNAc through the successive actions of UDP-GlcNAc 2-epimerase and UDP-ManNAc dehydrogenase. However, enzymatic conversion of UDP-GlcNAcA to UDP-ManNAcA was not detected. Ammonium sulfate protects both dehydrogenases from inactivation during storage and incubation. Partially purified UDP-GlcNAc dehydrogenase required dithiothreitol and the particulate fraction for its full activity. The apparent Km values of UDP-GlcNAc dehydrogenase for UDP-GlcNAc and NAD+ were 0.28 and 1.43 mM, respectively. The optimum pH of this enzyme was higher than 9 in Tris-HCl buffer. p-Chloromercuribenzoate at 27 microM as well as 10 mM ethanol almost completely inhibited the UDP-GlcNAc dehydrogenase reaction.

A 23-year-old patient with neurofibromatosis associated with acute myocardial infarction, vasospasm and a coronary artery ectasis.

We treated a 23-year-old male with neurofibromatosis with acute myocardial infarction. Cardiac catheterization revealed severe organic stenosis in the left anterior descending artery, an ectasic left circumflex artery and a small right coronary artery. Percutaneous transluminal coronary angioplasty (PTCA) was performed on the stenosis. In follow-up catheterizations, intracoronary administration of ergometrine induced vasospasm of the left coronary artery including at the PTCA site. An I 123 metaiodobenzylguanidine (MIBG) scintigram showed defects in the septum, inferior wall and apex. These findings suggest abnormality of the cardiac sympathetic nerve in neurofibromatosis.

[A case of teratoma in both the mediastinum and the intrapulmonary system].

A rare case of mature teratoma in both the mediastinum and the intrapulmonary system is presented. A 30-year-old male was admitted to our hospital due to tumor masses in the mediastinum and the left lung. We performed mediastinal tumor resection and left upper partial lobectomy. Neither tumor communicated with each other. Pathological findings revealed teratoma in the mediastinal lymph node and the intrapulmonary system including no malignant cells in either tumor. In this case, because metastasis and perforation were negative, we proposed that both tumors occurred at the same time in the early embryo.

Signal-averaged P-wave abnormalities and atrial size in patients with and without idiopathic paroxysmal atrial fibrillation.

BACKGROUND: The relation between abnormalities in the signal-averaged P wave and atrial size has not been determined in patients with paroxysmal atrial fibrillation (PAF) without structural heart disease. METHODS: Signal-averaged electrocardiograms of P waves were recorded in 38 patients with idiopathic PAF and 34 control subjects. Filtered P-wave duration (FPD) and root-mean-square voltages for the last 20 ms of the vector magnitude were measured. Atrial volume was calculated by cine magnetic resonance imaging. RESULTS: FPD was longer (131.7 +/- 10.9 ms vs 120.8 +/- 8.6 ms, P <.0001) and root-mean-square voltage was lower (2.89 +/- 1.29 microV vs 3.62 +/- 1.48 microV, P <.05) in the PAF group than in control subjects. However, the various atrial volumes were similar in the 2 groups. In controls, FPD was significantly correlated with left (r = 0.593, P <.0001) and total (r = 0.492, P <.005) atrial volume but not with right atrial volume. In patients with PAF, no significant correlations were found between FPD and any of the atrial volumes. Elderly patients with PAF (age > or =60 years) showed longer FPD than younger patients with PAF (139.2 +/- 9.4 ms vs 125.6 +/- 8.0 ms, P <.0001). CONCLUSIONS: FPD is influenced by the left and total atrial volumes in the normal heart without PAF. Prolonged FPD seems to be a useful predictor of idiopathic PAF among patients without atrial enlargement, especially in the elderly.

Plasma brain natriuretic peptide as a biochemical marker for atrioventricular sequence in patients with pacemakers.

We hypothesized that plasma brain natriuretic peptide, like plasma atrial natriuretic peptide, may reflect hemodynamic changes elicited by different cardiac pacing modes. The aim of this study was to investigate whether plasma brain natriuretic peptide could be influenced by different pacing modes or electrical stimulation. The subjects consisted of 164 patients with permanent pacemakers (52 VVI, 30 AAI, 82 DDD pacemakers) and unimpaired heart function. Patients with atrial fibrillation or spontaneous beats were excluded. Plasma atrial natriuretic peptide and brain natriuretic peptide levels were measured at a rate of 70 beats/min after 45 minutes in the supine position. Under ECG monitoring, the pacing mode was switched from DDD to VVI in 12 patients and from DDD to AAI in 4 patients with a dual chamber pacemaker. Plasma atrial natriuretic peptide and brain natriuretic peptide levels were also measured 30 minutes, 60 minutes, and 1 week after mode switching. Plasma atrial natriuretic peptide and brain natriuretic peptide levels were significantly higher in the nonphysiological pacing group than in the physiological pacing group, whereas these values were similar in the DDD and AAI pacing groups. One week after switching from DDD to VVI, plasma atrial natriuretic peptide and brain natriuretic peptide levels were significantly increased, however no significant changes were observed after switching to AAI. Based on a multivariate regression analysis of noninvasive clinical parameters, only a low plasma brain natriuretic peptide was significantly correlated with physiological pacing. We conclude that: (1) plasma brain natriuretic peptide, like atrial natriuretic peptide, is influenced by the pacing mode, but is not influenced by electrical stimulation; and (2) low plasma brain natriuretic peptide is important in relation to physiological pacing.