Mapping of class alpha glutathione S-transferase 2 (GST-2) genes to the vicinity of the d locus on mouse chromosome 9

Recombinant inbred strains of mice were used to localize the genes coding for the class alpha glutathione S-transferase 2 (Gst-2). The genes showed three distinct strain distribution patterns, indicating that they occur in at least three clusters separable by recombination. All three clusters are located in the vicinity of the d locus on mouse chromosome 9, but two of them are closer to d than the third. Linked to Gst-2 on mouse chromosome 9 are two enzyme-encoding loci, Pgm-3 and Mod-1. The human counterparts of Gst-2, Pgm-3, and Mod-1 map to 6p12, 6q12, and 6q12, respectively. Thus, the pericentric region of human chromosome 6 has its homolog in the segment spanning Gst-2, Pgm-3, and Mod-1 on mouse chromosome 9. The fact that the syntenic group extends across the centromere of human chromosome 6 can best be explained by a pericentric inversion postulated to have taken place in the primate lineage leading to Catarhini.     

Indoor environmental study and post occupancy evaluation in an office environment

1. 1. The objective of this paper is to investigate the indoor environment from the viewpoint of interaction between physical environment and the human responses. The field survey has been conducted over 1 year.

2. 2. A continuous measurement has been carried out for 1 week and distribution of variables have been measured for 1 day.

3. 3. The attitude of workers was investigated by a questionnaire.

4. 4. As the result, average luminance represented more than 1000 lx in the new building, in contrast with less tha 300 lx in the existing building.

5. 5. There was a significant difference of the occupants' response to the light environment between the two buildings.

6. 6. Measured thermal conditions are on the edge of the ASHRAE comfort envelope in summer, and in the neighborhood of the lower dry limit of the envelope in spring.

7. 7. The occupants' evaluations were remarkably changed before and after the moving. The office environment is better than that of the factory.

Low responsiveness of human neonatal lymphocytes to a B-cell mitogen, Staphylococcus aureus Cowan I (SpA CoI)

Responses of neonatal and adult lymphocytes to various mitogens were studied. Lymphocytes from umbilical cord blood (UCB) responded well to both phytohemagglutinin and concanavalin A, and also to pokeweed mitogen and Staphylococcus aureus Protein A. The responses of UCB lymphocytes to these mitogens were not significantly lower than those of adult peripheral blood lymphocytes (PBL). In contrast, UCB lymphocytes showed only a minimal response to killed Staphylococcus aureus Cowan I (SpA CoI), a potent B-cell mitogen for human PBL, although the proportion of B cells in UCB was not less than that in PBL. The low level of response of lymphocytes from UCB to SpA CoI was not ascribed to differences in dose response or kinetics. Purified B cells from UCB were not stimulated by SpA CoI either, suggesting tht the low responsiveness was not due to the suppressive effect of T cells or macrophages, but to some intrinsic defect in B cells in UCB. These results suggest that the B cells in neonates may be more immature than the T cells.     

Estimation of transport distance of fine particulate organic matter in relation to channel morphology in tailwaters of the Lake Biwa and reservoir dams

Knowledge on transport and deposition of fine particulate organic matter (FPOM) from reservoir dams is increasingly required for habitat management and restoration of dam tailwater ecosystems. Variations in the transport distance of FPOM, however, have never been studied well, particularly in relation to channel morphology, due to channel size restrictions of artificial tracers such as corn pollen when applied to larger river channels. This study aims to show the relations between FPOM retention efficiency and channel morphology in dam tailwaters using lentic plankters as tracers. We estimated the mean transport distance, S _p, by calculating downstream reduction ratios of lentic tracer plankters and calculated the deposition velocity, v _dep. Suspended FPOM samples were collected in tailwaters of two river channels below reservoir dams and two artificial canals below Lake Biwa in the Yodo River system. The longest S _p (19.2 km) and the shortest one (2.2 km) were recorded in the deep canal and shallow canal, respectively, showing a positive correlation with channel hydraulic radius. The values of v _dep were 4.7–6.4 times higher in river channels than in artificial canals. These results indicate that increasing complexity of bed morphology can minimize S _p, whereas bed degradation and armored bed materials may lead to increased S _p. Advantages of lentic plankters as tracers for estimating distance ranges of reservoir dam impact on river ecosystems are also discussed.     

Molecular Structure of Xanthocidin

In order to establish industrial production of 5′-inosinic acid (5′-IMP), a permeability mutant, KY13171, of Brevibacterium ammoniagenes, which accumulated 7 to 8 grams of 5′-IMP per liter and 4 to 6 grams of hypoxanthine (Hx) per liter (calculated as 5′-IMP), was improved by a genetical procedure. Further improved mutants were selected stepwise through repeating mutational work. The finally selected mutant. KY13369, accumulated 20 to 27 grams of 5′-IMP per liter, but not Hx.

Increased productivity of 5′-IMP and decreased productivity of Hx were not caused by the changes in 5′-IMP degrading activity, because these activities were not significantly different among the mutants. These results appear to indicate that the increased accumulation of 5′-IMP may be caused by the improvement in membrane permeability for 5′-IMP. However, the changes in phospholipid and fatty acid compositions were not enough to explain the increased permeability.     

Irradiation of titanium dioxide generates both singlet oxygen and superoxide anion.

Although photoexcited TiO2 has been known to initiate various chemical reactions, such as the generation of reactive oxygen species, precise mechanism and chemical nature of the generated species remain to be elucidated. The present work demonstrates the generation of singlet oxygen by irradiated TiO2 in ethanol as measured by ESR spectroscopy using 2,2,6,6-tetramethyl-4-piperidone (4-oxo-TMP) as a 1O2-sensitive trapping agent. Under identical conditions, the superoxide ion was also detected by spin trapping agent 5,5-dimethyl-pyrroline-N-oxide (DMPO). Kinetic analysis in the presence of both 4-oxo-TMP and DMPO revealed that singlet oxygen is produced directly at the irradiated TiO2 surface but not by a successive reaction involving superoxide anion. The basis for this view is the fact that DMPO added in the mixture increased the signals responsible for 4-oxo-2,2,6,6-tetramethyl-1-piperidinyloxy (4-oxo-TEMPO), a reaction product of 4-oxo-TMP and 1O2. The detailed mechanism for the generation of 1O2 and superoxide ion by irradiated TiO2 and reactions between these species and DMPO are discussed.