The bactericidal activity of tea and coffee

Extracts of black tea, green tea, pu-erh tea or coffee inhibited the growth of various bacteria known to cause diarrhoeal diseases. Tea or coffee also showed bactericidal activity against Staphylococcus aureus and Vibrio parahaemolyticus.     

Effects of vegetation cutting on the invasive plant Coreopsis lanceolata vary with vegetation type

The invasive plant Coreopsis lanceolata has established itself among various native vegetation types in Japan, but comparative studies of control effects among multiple vegetation types invaded by this plant are few. In the present study, experiments involving vegetation cutting at different frequencies were carried out on three vegetation types: Zoysia japonica dominant type (Zj), C. lanceolata dominant type (Cl) and Miscanthus sinensis dominant type (Ms). Responses of C. lanceolata to changes in cutting frequency varied with vegetation type. In Zj, the abundance of C. lanceolata increased when cutting was performed once or not at all, but tended to decrease when it was performed twice or thrice. In Cl, cutting once increased C. lanceolata, but this species was reduced when other cutting frequencies were employed. In Ms, C. lanceolata increased linearly with cutting frequency. The number of inflorescences of C. lanceolata in the plots was negatively correlated with cutting frequency in Zj and Cl. In Ms, the flowering of C. lanceolata was sometimes observed when cutting was performed only once. The most effective way to suppress C. lanceolata was not necessarily the best way to recover the natives. In Zj, cutting once positively influenced the abundances of native herbs, while cutting thrice or not at all tended to decrease them. In Cl and Ms, cutting thrice reduced the abundances of native herbs, while other cutting frequencies tended to increase them. To control invasive plants and restore the invaded vegetation effectively, the management approach should be changed flexibly in response to vegetation type, and careful monitoring of both invasive and native plants is desirable.     

Purification of C-reactive protein

A concise method was designed for preparation of C-reactive protein (CRP) from pleural effusion. By addition of L-alpha-lecithin to the pleural effusion in the presence of calcium ions, a flocculence of the CRP-lecithin complex formed. Subsequent treatment of the CRP-lecithin complex with chloroform and sodium citrate buffer enabled extraction of the CRP in the buffer layer. This extracted CRP was further purified by sequential treatment on column chromatography of DEAE cellulose (DE52) and gel filtration using Sephacryl S-300. The isolated protein was proved to be native CRP with a high degree of purity, as determined by electrophoretical and immunological analysis. The yield was 41.8% recovery from the starting material. E1%(280) of the CRP preparation was estimated to be 18.75.     

Female-specific target sites for both oestrogen and androgen in the teleost brain

To dissect the molecular and cellular basis of sexual differentiation of the teleost brain, which maintains marked sexual plasticity throughout life, we examined sex differences in neural expression of all subtypes of nuclear oestrogen and androgen receptors (ER and AR) in medaka. All receptors were differentially expressed between the sexes in specific nuclei in the forebrain. The most pronounced sex differences were found in several nuclei in the ventral telencephalic and preoptic areas, where ER and AR expression were prominent in females but almost completely absent in males, indicating that these nuclei represent female-specific target sites for both oestrogen and androgen in the brain. Subsequent analyses revealed that the female-specific expression of ER and AR is not under the direct control of sex-linked genes but is instead regulated positively by oestrogen and negatively by androgen in a transient and reversible manner. Taken together, the present study demonstrates that sex-specific target sites for both oestrogen and androgen occur in the brain as a result of the activational effects of gonadal steroids. The consequent sex-specific but reversible steroid sensitivity of the adult brain probably contributes substantially to the process of sexual differentiation and the persistent sexual plasticity of the teleost brain.     

The NFLD antigen in Japan

The low-frequency red cell antigen NFLD was identified in 2 Japanese donors. A family study showed that the antigen is not part of the P1 blood group system. Anti-NFLD was found in serum of several donors (frequency of 0.044%).     

Synovial Mononuclear Cells Consist with T Cells Which Produce High Levels of Tumor Necrosis Factor α

To determine whether synovial mononuclear cells include a population of tumor necrosis factor α-produeing T cells, we measured tumor necrosis α levels in culture supernatants of synovial mononuclear cells by ELISA and analyzed tumor necrosis α mRNA-positive cell frequencies. There were no significant differences in the spontaneous levels of TNF α between synovial mononuclear cells and peripheral mononuclear cells. The frequency of tumor necrosis factor α mRNA-positive cells in synovial mononuclear cells was higher than that of peripheral mononuclear cells. When stimulated with a superantigen, mononuclear cells from the synovial fluid of rheumatoid arthritis patients showed higher levels of tumor necrosis factor α production (1,035 ± 817 pg/ml) than did mononuclear cells from their peripheral blood (236 ± 180 pg/ml). In addition, we observed that a few T cell clones were resistant to superantigenic restimulation in vitro. We conclude that when these types of T cells persist in the synovium, they play a role in the development of rheumatoid arthritis via a mechanism involving tumor necrosis factor α production.