Pollutant runoff from non-point sources and its estimation by runoff models.

In order to attain a sound and sustainable water environment, it is important to carry out the environmental management of the watershed. For this purpose, knowledge on the pollutant runoff mechanism from non-point sources becomes very important especially under rainy conditions. At Isahaya, Nagasaki, Japan, a big project of construction of sea-dyke and reclamation is now going on, so reducing the pollutant runoff, especially from non-point sources, becomes more important. Some runoff models of rainwater are developed to predict the rate of pollutant loads from the non-point sources, and their results are compared with each other to investigate the accuracy of prediction. In this paper, runoff analysis of both rainwater and pollutants has been carried out using three models: the tank model, the kinematic wave (K-W) model, and a model using the digital elevation model (DEM). For precise estimation, it becomes necessary to identify the parameters included in these models. Here, total nitrogen has been considered as pollutants, and detachment rates are evaluated, correlated with a class of land use, soil type, and moisture content. Finally, it has been shown that pollutant runoff from non-point sources can be predicted fairly well, identifying the model parameter appropriately.

Micronucleus induction in mouse peripheral reticulocytes by 7,12-dimethylbenz[a]anthracene.

Micronucleus assays using mouse peripheral blood stained vitally on acridine orange (AO)-coated slides were evaluated at two laboratories with 7,12-dimethylbenz[a]anthracene (DMBA) and compared with the standard bone marrow assay. DMBA was administered by single intraperitoneal injection to CD-1 mice at doses ranging from 5 to 80 mg/kg, then 5 microliters of peripheral blood was sampled from a tail vein at 24, 48, 72, 96, and 120 h after treatment. Similar incidences of micronucleated young erythrocytes were observed in peripheral blood reticulocytes and bone marrow polychromatic erythrocytes. The dose response of micronucleated reticulocytes was delayed compared to that of micronucleated polychromatic erythrocytes. The dose-response curves after treatment with DMBA differed depending on the sampling times, which revealed the difficulty of obtaining accurate dose-response relations in the micronucleus assay. The present result demonstrated that the simple and rapid AO supravital staining method is a valuable and easier method for obtaining dose- and time-response data for quantification of micronucleus induction by chemicals.

[Clinical study on two cases of progressive systemic sclerosis with anti Wa antibody].

It is well known that patients with progressive systemic sclerosis (PSS), as well as other autoimmune disease, have various kinds of autoantibodies. We presented two PSS patients with anti Wa antibody, which had recently been reported as a new anti cytoplasmic antibody in only one case with PSS. Our first case, 49 years old female had clinical features of arthralgia, Raynaud's phenomenon, sclerodactyly, transient myalgia and sicca complex. Her laboratory findings showed hypergammaglobulinemia (1.9 g/dl), positive RAHA (1: 640) anti Wa antibody (1: 256), and anti SS-A antibody (1: 256). Second case, 64 years old female had also clinical features of Raynaud's phenomenon, sclerodactyly, dysphagia, dyspnea on exertion and dry mouth. Furthermore lung fibrosis and dysmobility of upper GI tract were observed. FANA (1: 20) was detected as nucleolar pattern, and the titer of anti Wa antibody was 1: 64. Clinical findings of myositis were not seen in both cases. This study suggested that anti Wa antibody might be one of the diagnostic marker on PSS.

Precipitating antimitochondrial antibodies in Japanese patients with primary biliary cirrhosis.

The prevalence of three precipitating antibodies to mitochondria A (M-A), mitochondria B (M-B), and mitochondria C (M-C), reacting with the antigens in the mitochondrial fraction of sonicated rat liver was studied in Japanese patients with primary biliary cirrhosis and other liver diseases. Antibodies to M-A and M-B were found in 12 of 22 (54%) and 11 of 22 (50%) patients, respectively. Antibodies to M-C were found in only one of 22 (4%) patients. The titers of antibodies to M-A and M-B correlated with the titers of mitochondrial immunofluorescence staining on unfixed mouse kidney section (r = 0.71 and 0.81, respectively). These antibodies were not present in liver cirrhosis (20 patients), chronic active hepatitis (20), acute viral hepatitis (10), and hepatoma (10). However, the titers of these antibodies did not correlate with amount of immunoglobulin, immune complexes, and the severity of disease. This work confirms that the antibodies to M-A and M-B are also marker antibodies for Japanese patients with primary biliary cirrhosis.