Purification and characterization of a 100 kDa DNA polymerase from cauliflower inflorescence.

A DNA polymerase from cauliflower (Brassica oleracea var. botrytis) inflorescence has been purified to near homogeneity through five successive column chromatographies, and temporally designated cauliflower polymerase 1. Cauliflower polymerase 1 is a monopolypeptide with a molecular mass of 100 kDa. The enzyme efficiently uses synthetic DNA homopolymers and moderately activated DNA and a synthetic RNA homopolymer as template-primers. The enzyme is strongly sensitive to dideoxythymidine triphosphate and N-ethylmaleimide, but it is insensitive to aphidicolin. It was stimulated with 250 mM KCl. Its mode of DNA synthesis is high-processive with or without proliferating-cell nuclear antigen. A 3'-->5' exonuclease activity is associated with cauliflower polymerase 1. The enzyme is clearly different from cauliflower mitochondrial polymerase and does not resemble the four different types of wheat DNA polymerase, designated wheat DNA polymerases A, B, CI and CII. In the present paper the role of the enzyme in plant DNA synthesis is discussed.

[A case of interstitial pneumonitis associated with polymyositis complicated by renal cell carcinoma].

A 55-year-old woman was referred to the department of urology in our hospital with left renal tumor, discovered during examinations at another hospital for fever and dyspnea on exertion. Because surgery was difficult due to severe hypoxemia, pulmonary function impairment (restrictive) and bilateral diffuse interstitial shadows on chest X-ray film, the patient was referred to our department. Interstitial pneumonitis was found on transbronchial lung biopsy, and serum GOT, LDH and CPK values were elevated. These symptoms and abnormalities of laboratory data were improved by administration of prednisolone 60 mg/day, and left nephrectomy was performed without any complications. Pathological examination of the surgical specimen showed clear cell carcinoma (Grawitz). Steroid therapy was tapered off and her clinical course was good. Six months after surgery, the patient developed a recurrence of fever, which was not responsive to antibiotics. Polymyositis was diagnosed on the basis of elevated serum GOT, LDH and CPK, electromyogram and muscle biopsy findings and positive anti-Jo-1 antibody. Polymyositis/dermatomyositis is sometimes associated with interstitial pneumonitis or malignant neoplasms, but rarely with both simultaneously. Moreover, renal cell carcinoma is very rare among the malignant neoplasms associated with polymyositis/dermatomyositis, and we therefore report this unusual case.

[A case of exogenous lipoid pneumonia showing a coin lesion with cavities].

A 26-year-old male was referred to our department because of an abnormal chest X-ray, obtained during a routine physical examination in the hospital admitted after a traffic accident. The P-A chest film revealed a coin lesion with cavities in the left S9. He complained of no symptoms except for expectoration of bloody sputum. Transbronchial lung biopsy specimens showed destruction of normal alveolar pattern and collections of lipid-laden macrophages enclosed by fibrous tissue. The lipid material of macrophages in sputum was stained with Sudan III. He had no difficulty in swallowing and no history of regular use of oily drugs. Fiberoptic bronchoscopy and chest CT showed no obstruction of bronchi. He had been working in a repair shop for motorcycles for years, therefore the lesion could be an occupational exogenous lipoid pneumonia. The diameter of the coin lesion has decreased without any therapy.