A novel function of enolase from rabbit muscle; an immunoglobulin production stimulating factor.

Rabbit muscle enolase stimulates immunoglobulin production by a human hybridoma line, HB4C5 cells under serum-free condition. IgM productivity of HB4C5 cells was enhanced more than 20-fold by this enzyme at 220 micro/ml. Human peripheral blood lymphocytes were also facilitated their IgM and IgG productivity in the serum-free medium. However, baker's yeast enolase was ineffective to accelerate immunoglobulin production by HB4C5 cells, in spite of the same specific enzymatic activity as rabbit muscle enolase. There were differences in sensitivities against heat treatment and trypsin digestion between IPSF and enzymatic activities of enolase. These results imply that the immunoglobulin production stimulating effect of rabbit muscle enolase is irrelevant to its enzymatic function and reaction products. This fact also means that this enzyme has another function other than enzymatic one in glycolysis. Rabbit muscle enolase enhanced IgM production of transcription-suppressed HB4C5 cells treated with actinomycin D. Cycloheximide treatment of HB4C5 cells was useless to inhibit the expression of immunoglobulin production stimulating activity. However, inhibition of post-transcriptional process by monensin invalidated the activity of enolase. These findings suggest that enolase from rabbit muscle accelerates the steps between translation and post-translational processes to enhance immunoglobulin productivity. In addition, laser confocal microscopic analysis revealed that enolase from rabbit muscle was subsequently incorporated by HB4C5 cells.

Bartter's syndrome with gouty arthritis.

A 45-year-old woman with Bartter's syndrome complicated with gouty arthritis is reported. Bartter's syndrome was diagnosed from hypokalemia, metabolic alkalosis, high plasma renin activity, normal blood pressure and attenuated pressor response to exogenous angiotensin II infusion. Serum uric acid was 11.8 mg/dl, the renal clearance of uric acid was low (3.0 ml/min) and fractional excretion of uric acid (FEUA) was 7.0%, being the lower limit of the normal range. Fractional excretion of phosphate was low (5.3%) and fractional free water clearance per fractional distal sodium delivery was 0.51. The mechanism of hyperuricemia in this case is discussed.

Giant noninflammatory and nonatherosclerotic coronary arterial aneurysm in the left main trunk assessed by intravascular ultrasound imaging--a case report.

A case of a giant noninflammatory and nonatherosclerotic coronary arterial aneurysm in the left main trunk of a 69-year-old female is reported. Preoperative intravascular ultrasound (IVUS) images were helpful for visualizing the morphologic and histologic features of the coronary aneurysm. They were also useful for determining the etiologic background and surgical procedure.

[Marked dilatation of the bilateral common carotid artery: a case report].

We reported a rare case of marked dilatation of the bilateral common carotid artery (CCA) associated with stenosis of the left middle cerebral artery (MCA). A 64-year-old female was admitted with right hemiparesis and dysarthria. She was hospitalized 2 years ago for cholecystitis. For 5 years, she has been under medical treatment for hypertension, diabetes mellitus, hyperlipidemia, cardiac failure associated with hypertrophic cardiomyopathy, and atrial fibrillation. Brain CT scan showed infarction of the left corona radiata. Angiography revealed marked dilatation of the bilateral CCA and the internal carotid artery (ICA), moderate dilatation of the innominate artery and the right subclavian artery, kinking of the right CCA, diverticular outpouching of the left ICA, and stenosis of the right external carotid artery and the left MCA. Breast CT scan revealed moderate dilatation and marked calcification of the ascending aorta and the aortic arch. Laboratory examination did not show any sign of inflammation, rheumatoid factor (RA), antistreptolysis-O (ASLO) and antinucleotic antibody. Based on the clinical course, radiological findings and laboratory data, possible diagnosis of the dilatation of the bilateral CCA was discussed with particular emphasis on arteriosclerotic aneurysm and aortitis syndrome.

A case of swallow syncope induced by vagovagal reflex.

A 65-year-old man experienced syncope associated with advanced atrioventricular (AV) block upon swallowing. Continuous electrocardiogram (ECG) monitoring revealed first and second degree AV block. ECG revealed advanced AV block (Max R-R 6.38 s) upon swallowing, a cold drink. Demand ventricular pacing alleviated his symptoms. In this patient, the advanced AV block might have been precipitated by a vagovagal reflex triggered by expansion of the esophagus, resulting in selective suppression of the atrioventricular node.