[Prevalence of cervical and cerebral atherosclerosis and silent brain infarction in patients with multivessel coronary artery disease].

OBJECTIVES: This clinical study investigated the prevalence of cervical and cerebral atherosclerosis and silent brain infarction in patients with coronary artery disease. METHODS: Cervical and cerebral magnetic resonance angiography(MRA) was performed in 133 patients (98 males, 35 females, mean age 65.3 years) with suspected coronary artery disease, who were divided into a zero- and one-vessel disease group(n = 71) and a two- and three-vessel disease group(n = 62) depending on the number of major coronary branches with 75% or more stenosis. The MRA lesion was defined as more than 50% stenosis. Magnetic resonance imaging(MRI) of the brain was performed within 1 week of MRA in 78 patients without symptomatic stroke and atrial fibrillation. Silent brain infarction on MRI was defined as a focal high intensity area on T2-weighted images larger than 3 mm. RESULTS: The prevalence of MRA lesions was significantly greater in the two- and three-vessel group than in the zero- and one-vessel group(53% vs 14%, p < 0.01). The prevalence of MRI lesion was significantly higher in the two- and three-vessel group than in the zero- and one-vessel group(77% vs 36%, p < 0.01). The size and number of the MRI lesions were also significantly greater in the two- and three-vessel group than in the zero- and one-vessel group(p < 0.01). Neither age nor percentage of male gender was different between the groups. Diabetes mellitus was the common risk factor for coronary artery disease, MRA lesion and MRI lesion. CONCLUSIONS: Cervical and cerebral atherosclerosis and silent brain infarction are frequently observed in patients with multivessel coronary artery disease.

[Ki-1-positive anaplastic large-cell lymphoma with mediastinal involvement].

A 30-year-old woman was admitted to our hospital because of an abnormal mass shadow in the right side of the mediastinum on a a chest X-ray film. The chest X-ray film and computed tomogram revealed a mass approximately 4.8 cm in diameter in the right side of the mediastinum. The mass had invaded the right supraclavicular fossa. Lymph-node biopsy was done. Microscopical examination of an HE-stained specimen of a supraclavicular lymph nodes showed prediferation of large atypical lymphocytes. These atypical lymphocytes were stained immunohistochemically with anti-Ki-1 antibody. No T cell or B cell markers were found on these cells. No other tumors were detected by radiological examination. Therefore, our diagnosis was anaplastic large-cell lymphoma, which is identical to Ki-1 lymphoma of the mediastinum.

Cloning and expression of the Erwinia herbicola tyrosine phenol-lyase gene in Escherichia coli.

The tyrosine phenol-lyase (TPL) gene of Erwinia herbicola was cloned and expressed in Escherichia coli, and the complete nucleotide sequence of the gene determined. The TPL gene comprises 1368 bp, encoding 456 amino acids which have 90% amino acid identity with TPL from Citrobacter freundii. After replacing the 5'-flanking region of the TPL gene with the E. coli lac promoter, TPL protein could be hyperproduced constitutively in E. coli without induction by L-tyrosine.

Enzymatic production of L-tryptophan from DL-serine and indole by a coupled reaction of tryptophan synthase and amino acid racemase.

Enzymatic production of L-tryptophan from DL-serine and indole by a coupled reaction of tryptophan synthase and amino acid racemase was studied. The tryptophan synthase (EC 4.2.1.20) of Escherichia coli catalyzed beta-substitution reaction of L-serine into L-tryptophan and the amino acid racemase (EC 5.1.1.10) of Pseudomonas putida catalyzed the racemization of D-serine simultaneously in one reactor. Under optimal conditions established for L-tryptophan production, a large-scale production of L-tryptophan was carried out in a 200-liter reactor using intact cells of E. coli and P. putida. After 24 h of incubation with intermittent indole feeding, 110 g liter-1 of L-tryptophan was formed in molar yields of 91 and 100% for added DL-serine and indole, respectively. Continuous production of L-tryptophan was also carried out using immobilized cells of E. coli and P. putida. The maximum concentration of L-tryptophan formed was 5.2 g liter-1 (99% molar yield for indole), and the concentration decreased to 4.2 g liter-1 after continuous operation for 20 days.