[Exposure of primary school children and their mothers to nitrogen dioxide in Sapporo City: comparisons of groups clustered by maternal daily behavior and habits]

Exposure of primary school children and their mothers to NO2 was investigated in two schools in the city of Sapporo. One school was located in the city center and another in a suburb of the city. The school children and mothers were requested to put on NO2 filter badges for 24 hours and to record activity during that period. They were also requested to fill out ATS-DLD questionnaires. The surveys were repeated twice, in the summer of 1986 and in the winter 1987, due to possible seasonal variation. Average NO2 exposure levels of both school children and mothers were lower in the summer than the corresponding averages in the winter. The average of the children was lower than that of mothers in both summer and winter. Averages of the children of the city-center school were higher than those of children in the school in the suburb in both summer and winter. These differences were not observed in mothers' averages. To examine the relationship between NO2 exposure levels and maternal daily behavior and habits, the subjects were classified into three clusters by employment status, living area, smoking habits, type of heating appliance, and use of fans during cooking. While average NO2 exposure levels of children were similar among the three clusters, the average of the mothers of the third cluster was the highest among the clusters in either summer or winter. The third cluster was characterized by the highest rate of employment among the clusters, spending less time in their kitchens and not using fans regularly.(ABSTRACT TRUNCATED AT 250 WORDS)

[Extracellular purine catabolites and tissue nucleotides and purine catabolites during progression and recovery of ischemia]

During progression and recovery of ischemia, extracellular purine catabolites were measured and compared with purine catabolites and adenine nucleotide levels in the tissue. Ischemia was induced by bilateral occlusion of the common carotid arteries in gerbil. Extracellular purine catabolites were sampled by in vivo brain microdialysis technique, and tissue adenine nucleotides and purine catabolites were extracted from in situ frozen and lypholized brain tissue. These metabolites were measured with simple method of isoclatic condition by HPLC system. Ischemia depleted tissue ATP and ADP, whereas AMP and purine catabolites accumulated strikingly. In parallel, extracellular purine catabolites increased as consecutive degradation on the biochemical metabolic pathway in the same animal. Levels of tissue ATP and adenosine normalized in the recovery phase of ischemia immediately. However, extracellular purine catabolites during the recovery are much higher than those during the progression of ischemia. These data indicated extracellular high levels of purine catabolites during the ischemic insult, and especially adenosine as neuromodulator which may turn off spontaneous neuronal activity and exert antiepileptic effects during the recovery rather than the progression of ischemia.

Inhibition of infectivity of human immunodeficiency virus by a novel nucleoside, oxetanocin, and related compounds

Oxetanocin is a novel nucleoside containing a 4-membered sugar, oxetanosyl-N-glycoside, and adenine. The effects of oxetanocin and related compounds on the infectivity of human immunodeficiency virus (HIV) were examined. They inhibited HIV infectivity in vitro. Allopurinol and mycophenolic acid produced additive anti-HIV effects when added with these compounds.

[A case of pseudolymphoma of the lung with cough and fever]

This case report presents a 48-year-old woman who had been suffering from cough and fever for 5 years. A large mass in the right lung was pointed out. Even after various examinations, we couldn't resolve the difficult diagnostic problems involved, but it was clear that there were no signs of a malignant tumor. We suspected a large benign tumor or pulmonary sequestration. Right lower lobectomy was performed and histological examinations of the resected tumor revealed lymphoproliferative disorder. Microscopic examinations of the specimen disclosed monotonous lymphoid cells proliferation (small to medium size) without definite lymph follicles or germinal centers. Lymph follicles were clearly demonstrated with the immunoperoxidase method. These findings were interpreted to be consistent with what has been recently called pseudolymphoma of the lung and prompted discussions on the reasonableness of criteria for the diagnosis of various pseudolymphoma and effective immunological examinations for the clarification of the etiology.

[S-adenosyl-L-methionine concentration in cerebral interstitial fluid monitored by intracerebral microdialysis]

Ketamine-anesthetized gerbils were implanted with 0.5 mm diameter microdialysis tubing through the cortex, hippocampus and thalamus with a stereotaxic instrument. The cannula was perfused with artificial cerebrospinal fluid at a flow rate of 2 microliters/min. Samples of the perfusate representing the cerebral interstitial fluid were collected and subsequently analyzed for their content of S-adenosyl-L-methionine (SAM) with high performance liquid chromatography (HPLC). In vitro tests using the dialysis cannula gave SAM recovery which varied from 3.44 +/- 0.31% (n = 3) at a perfusion flow rate of 8 microliters/min to 43.8 +/- 3.81% (n = 3) at 0.5 microliters/min (mean +/- SEM). The in vivo SAM content of the perfusate was studied and the endogenous SAM level in cerebral interstitial fluid of gerbil was 3.49 +/- 1.52 nmol per ml (n = 3). Intraperitoneal injection of SAM (250 mg/kg) produced 10-fold increases in the perfusate SAM concentration. After the experiment the brains were checked by immunopathological study using anti-albumin antibody to examine the degree of damage to the blood-brain barrier permeability. These results show that intracerebral microdialysis offers several potential advantages for studies of extracellular neurochemistry.

Selective inhibition of human cytomegalovirus replication by a novel nucleoside, oxetanocin G

A novel nucleoside with an oxetanosyl-N-glycoside has been recently isolated from a culture filtrate from Bacillus megaterium and named oxetanocin A (N. Shimada, S. Hasegawa, T. Harada, T. Tomisawa, A. Fujii, and T. Takita, J. Antibiot. 39:1623-1625, 1986). In this study, we evaluated the antiherpesvirus activity of oxetanocin A and its derivatives and found that 9-(2-deoxy-2-hydroxymethyl-beta-D-erythro-oxetanosyl)guanine (OXT-G) was very potent and selective in inhibiting the replication of human cytomegalovirus (HCMV) in vitro. The median effective concentration for HCMV strain AD169 was 1.0 microgram/ml, and that for herpes simplex virus type 2 strain 186 was 3.5 micrograms/ml. The selectivity index, based on the ratio of the median inhibitory concentration for cell growth of human diploid fibroblasts to the median effective concentration for HCMV plaque formation, was more than 300. The synthesis of HCMV-induced late polypeptides such as the 150,000-molecular-weight capsid and the 68,000-molecular-weight major matrix proteins was strongly suppressed when OXT-G (5 micrograms/ml) was added to the cultures at the beginning of infection. At this concentration of OXT-G, the amount of HCMV DNA detected in the drug-treated infected cells was less than 1/10 of that detected in the infected control cells. The results suggest that the mode of action of OXT-G is inhibition of viral replication by impairing the viral DNA synthesis.

Mode of action of deoxypheganomycin D on Mycobacterium smegmatis ATCC 607

Deoxypheganomycin D, a specific inhibitor of mycobacteria, inhibits the growth in vitro of Mycobacterium smegmatis ATCC 607 (M. 607) bacteriostatically at concentrations as high as 7 X 10(-5) M. It shows no cross-resistance to paromomycin, capreomycin, viomycin, streptothricin, kanamycin and streptomycin. Deoxypheganomycin D at 2.8 X 10(-7) M where the cell growth of M. 607 is only partially inhibited does not significantly inhibit DNA, RNA or protein synthesis but leads to marked decrease (13% of control) in [14C]glycerol-derived radioactivity in cell-walls. In the presence of 7 X 10(-6) M deoxypheganomycin D, the influx of leucine but not thymidine is affected while the reverse is true with efflux. The data suggest that the effect of deoxypheganomycin D on M. 607 may be related to both the cell membrane and specific mycobacterial lipid like components of the cell-wall.