Isolation and characterization of mouse CD7 cDNA

The human CD7 antigen is a glycoprotein, M _r 40 000, expressed on the surface of peripheral blood T-lymphocytes and thymocytes, and is the earliest surface antigen to appear on T-cell lineage cells. In this study, putative mouse CD7 cDNA was identified based on its similarities with human CD7. Five independent clones originating from the same mRNA species were isolated (designated as mCD7) by screening a mouse thymocyte cDNA library with human CD7 cDNA, J61, under moderate stringency. The longest insert of a 995 base pair had an open reading frame of 210 amino acids. Northern blot analysis using the mouse CD7 cDNA probe demonstrated a single 1.2 kilobase mRNA ni the thymus, spleen, bone marrow, and small intestine. The protein deduced from mCD7 cDNA consisted of the leader, extracellular, transmembrane, and cytoplasmic domains of 24, 126, 21, and 39 amino acids, respectively, based on the hydrophobicity plot and the structure of human CD7. The extracellualr domain contained three potential N-glycosilation sites, while the cytoplasmic domain contained one potential protein kinase C phosphorylation site. The amino acid sequence had 45.5% similarity with human CD7, while the similarities for the individual domains ranged from 49.2% to 63.2%. The six highly conserved regions, which may possibly be involved with still unknown CD7-mediated functions, were located in the extracellular and cytoplasmic domains.The nucleotide sequence data reported in this paper have seen submitted to the GenBank, DDBJ, and EMBL nucleotide sequence database and have been assigned the accession number D10329.     

Serum γ-Glutamyl Transpeptidase Levels and Hypertension in Non-drinkers: A Possible Role of Fatty Liver in the Pathogenesis of Obesity Related Hypertension

The relationships between increases in body mass index (BMI) and increases in hypertension were compared between non-drinkers with elevated serum γ-glutamyl transpeptidase (γ-GTP) levels (≥50 U/I) and those with normal levels, who comprised 10,952 men and 22,107 women aged 40–59 years recruited from an occupational health clinic. Hypertension was found in 16.1% and 13.5% of the men and women, and elevated serum γ-GTP was found in 10.8% and 2.8% of the men and women, respectively. The prevalences of hypertension and elevated serum y-GTP levels were both increased with increased BMI. Hypertension was, however, shown to be 1.5 times more prevalent in the persons with elevated serum γ-GTP levels than in those with normal levels in both sexes, even after adjusting for BMI by a multiple logistic analysis. It can be concluded that elevations of serum γ-GTP, which are probably a reflection of fatty liver in the non-drinkers, are closely related to the development of hypertension associated with increased obesity.     

Improved regeneration response of creeping bentgrass and japonica rice by maltose and lactose

The effect of alternative carbohydrate sources to sucrose for plant regeneration from long-term cell cultures of creeping bentgrass (Agrostis palustris Huds.cv.Penncross) and japonica rice (Oryza sativa L.cv.Nipponbare) was studied. Both maltose and lactose supported a higher degree of regeneration compared to sucrose; in 8-and 19-month-old cultures of creeping bentgrass, the frequencies of regenerating calli remained at 76–93% and the numbers of plants regenerated were 8 to 36-fold higher. In 35-month-old cultures of japonica rice, 2–4% of the calli were capable of regeneration on maltose and lactose media. These results indicate that loss of plant regeneration in long-term cultures is caused, at least in part, by specific cultural conditions and not by genetic changes.     

Protein polymorphism in two populations of the wild quail Coturnix coturnix japonica

To evaluate genetic variability in two populations of the wild quail Cofurnix coturnix japonica , proteins and enzymes were examined by starch gel electrophoresis.
Rare variants so far not observed in domestic quail were found in the following five enzymes; aspartate aminotransferase, acid phosphatase, pancreatic esterase, isocitrate dehydrogenase and lactate dehydrogenase. The proportion of polymorphic loci ( P _poly) and the expected average heterozygosity ( H ) in one of the two populations were estimated to be 0.484 (15/31) and 0.085, respectively. Those in another population were 0.433 (13/30) and 0.086, respectively. The genetic distance (Nei, 1975) between the two wild quail populations was D = 0.0074. D values of 0.0321 and 0.0189 were estimated between the laboratory quail population previously examined (Kimura et al., 1982) and each of these two wild populations.     

Purification and properties of human pancreas dipeptidase

Dipeptidase [EC 3.4.13] was purified from human pancreas; the activity was followed with L-Leu-L-Leu as a substrate. Polyacrylamide gel electrophoresis showed that the final preparation was homogeneous. The molecular weight of the dipeptidase was estimated to be 135,000 by gel filtration. From the result of SDS-polyacrylamide gel electrophoresis, it was found that the enzyme consisted of two subunits with equal molecular weights of 68,000. By atomic absorption analysis, the dipeptidase was shown to be a zinc metalloenzyme containing one atom of zinc for each subunit. Cu2+ and Hg2+ (1 mM) inhibited the enzyme by 50%. o-Phenanthroline strongly inhibited the enzyme. The dipeptidase hydrolyzed dipeptides such as L-Ala-L-Ala, L-Met-L-Met, L-Ala-L-Leu, L-Leu-Gly, and L-Leu-L-Leu but did not hydrolyze tripeptides, Bz-amino acids, CBz-amino acids, or L-amino acid beta-naphthylamides. The dipeptidase from human pancreas was immunologically distinct from human liver dipeptidase.     

Seven new bibenzyls and a dihydrochalcone from Radula variabilis

Six new bibenzyls have been isolated from the liverwort, Radula variabilis and their structures have been established by chemical and spectral evidence. In addition, a new dihydrochalcone and a new bibenzy] have been isolated as their methyl ethers. Except for two of the bibenzyls, the present compounds have a unique seven-membered heterocyclic ring and they are the first members of a new group of natural product.     

Effect of nutritional factors on shikonin derivative formation in Lithospermum callus cultures

Some nutritional factors affecting the biosynthesis of shikonin derivatives in callus cultures of Lithospermum erythrorhizon were examined. High sucrose concentrations increased the content of shikonin derivatives, but neither glucose nor fructose was effective for shikonin derivative formation. High concentrations of nitrogen sources inhibited or retarded shikonin derivative formation and streptomycin sulphate stimulated their biosynthesis. Addition of ascorbic acid increased the content of shikonin derivatives. Among some precursors tested only l-phenylalanine had a positive effect. At high concentrations, Ca²⁺ and Fe²⁺ inhibited the biosynthesis of shikonin derivatives.