Quercetin inhibited DNA synthesis and induced apoptosis associated with increase in c-fos mRNA level and the upregulation of p21WAF1CIP1 mRNA and protein expression during liver regeneration after partial hepatectomy

Quercetin, a widely distributed bioflavonoid, inhibited DNA synthesis in regenerating liver after partial hepatectomy. This inhibition was accompanied by apoptosis, evidenced by in situ end-labeling and gel electrophoresis of DNA fragmentation. Characteristic DNA fragmentation was detected as early as 2 h after injection. Northern blot analysis revealed that quercetin induced the increases in c-fos and p21WAF1CIP1 mRNA levels within 2 h. The expression of p21 protein was also enhanced, while p53 mRNA and protein levels were not affected by quercetin. These results suggest that quercetin-induced apoptosis is associated with the increase in c-fos mRNA level and the upregulation of p21 mRNA and protein expression, probably in a p53-independent pathway.     

Aspartate kinase-independent lysine synthesis in an extremely thermophilic bacterium, Thermus thermophilus: lysine is synthesized via alpha-aminoadipic acid not via diaminopimelic acid

An aspartate kinase-deficient mutant of Thermus thermophilus, AK001, was constructed. The mutant strain did not grow in a minimal medium, suggesting that T. thermophilus contains a single aspartate kinase. Growth of the mutant strain was restored by addition of both threonine and methionine, while addition of lysine had no detectable effect on growth. To further elucidate the lysine biosynthetic pathway in T. thermophilus, lysine auxotrophic mutants of T. thermophilus were obtained by chemical mutagenesis. For all lysine auxotrophic mutants, growth in a minimal medium was not restored by addition of diaminopimelic acid, whereas growth of two mutants was restored by addition of alpha-aminoadipic acid, a precursor of lysine in biosynthetic pathways of yeast and fungi. A BamHI fragment of 4.34 kb which complemented the lysine auxotrophy of a mutant was cloned. Determination of the nucleotide sequence suggested the presence of homoaconitate hydratase genes, termed hacA and hacB, which could encode large and small subunits of homoaconitate hydratase, in the cloned fragment. Disruption of the chromosomal copy of hacA yielded mutants showing lysine auxotrophy which was restored by addition of alpha-aminoadipic acid or alpha-ketoadipic acid. All of these results indicated that in T. thermophilus, lysine was not synthesized via the diaminopimelic acid pathway, believed to be common to all bacteria, but via a pathway using alpha-aminoadipic acid as a biosynthetic intermediate.     

Chloroplast phylogeny indicates that bryophytes are monophyletic

Opinions on the basal relationship of land plants vary considerably and no phylogenetic tree with significant statistical support has been obtained. Here, we report phylogenetic analyses using 51 genes from the entire chloroplast genome sequences of 20 representative green plant species. The analyses, using translated amino acid sequences, indicated that extant bryophytes (mosses, liverworts, and hornworts) form a monophyletic group with high statistical confidence and that extant bryophytes are likely sisters to extant vascular plants, although the support for monophyletic vascular plants was not strong. Analyses at the nucleotide level could not resolve the basal relationship with statistical confidence. Bryophyte monophyly inferred using amino acid sequences has a good statistical foundation and is not rejected statistically by other data sets. We propose bryophyte monophyly as the currently best hypothesis.     

Establishment and characterization of human uterine cervical epidermoid carcinoma cell line HHUS containing HPV 59 DNA

The cell line designated HHUS was established from human uterine cervical keratinizing squamous cell carcinoma. The HHUS cell line was subcultivated more than 70 times within 3 years. The cultured cells, polygonal or spindle, with neoplastic and pleomorphic features, appeared epithelial in shape, with a pavement-like arrangement and grew in multi-layers without contact inhibition. The chromosome number was varied from 40 to 88, and the modal number was stable in diploid range. The cultured cells produced keratinizing squamous cell carcinomas by heterotransplantation into the subcutis of nude mice. The HHUS cells were characterized as producing large amounts of SCC, in vitro and possessing HPV-59 DNA genomes.     

Royal jelly inhibits the production of proinflammatory cytokines by activated macrophages

In this study, we have examined the anti-inflammatory actions of royal jelly (RJ) at a cytokine level. When supernatants of RJ suspensions were added to a culture of mouse peritoneal macrophages stimulated with lipopolysaccharide and IFN-gamma, the production of proinflammatory cytokines, such as TNF-alpha, IL-6, and IL-1, was efficiently inhibited in a dose-dependent manner without having cytotoxic effects on macrophages. This suggests that RJ contains factor(s) responsible for the suppression of proinflammatory cytokine secretion. We named the factor for honeybees RJ-derived anti-inflammatory factor (HBRJ-AIF), and further investigated the molecular aspects of it. Size fractionation study showed that HBRJ-AIF is composed of substances of low (< 5 kDa) and high (> 30 kDa) molecular weights, with the former being a major component. Chromatographic analysis showed that MRJP3 is one candidate for the HBRJ-AIF with high molecular weights. Thus, our results suggest that RJ has anti-inflammatory actions through inhibiting proinflammatory cytokine production by activated macrophages.     

Identification of a collagen production-promoting factor from an extract of royal jelly and its possible mechanism

We have previously shown that royal jelly (RJ) promoted collagen production by skin fibroblasts in the presence of ascorbic acid-2-O-alpha-glucoside (AA-2G). In this study, we purified the honeybee RJ-derived collagen production-promoting factor (HBRJ-CPF) from an alkali-solubilized fraction of RJ by C18 reverse-phase column chromatography. The elution profile by the C18 column chromatography and the molecular mass of the purified HBRJ-CPF material coincided with those of 10-hydroxy-2-decenoic acid (10H2DA). We then examined the collagen production-promoting activities of several commercially available fatty acids contained in RJ. We found that 10H2DA and 10-hydroxydecanoic acid increased the collagen production in a dose-dependent manner. Furthermore, 10H2DA induced the fibroblast cell line, NHDF, to produce transforming growth factor-beta 1 (TGF-beta 1) which is an important factor for collagen production. As expected, the collagen production-promoting activity of 10H2DA was neutralized by the anti-TGF-beta 1 antibody. These result suggest that HBRJ-CPF identified as 10H2DA promoted the collagen production of AA-2G-treated fibroblasts by inducing TGF-beta 1 production.     

Aroma sensing and indoor air monitoring by quartz crystal resonators with sensory films prepared by sputtering of biomaterials and sintered polymers

Thickness shear mode quartz-crystal resonator coated with plasma polymer films (PPFs) produced by radio-frequency sputtering of biomaterials and synthetic polymers were examined with respect to their abilities to continuously monitor indoor air. We confirmed the sensory capabilities of an array of PPF sensors to aromas emitted from essential oils at concentrations as low as the detection threshold of human olfaction. Changes in humidity induced a drift in the response curves of PPF sensors. On the contrary, volatile compounds exhibited pulse signals. The pulse signals of a D-phenylalanine sensor and a polyethylene sensor were synchronous, but the direction of the peaks was inverted in most cases. Compared with a photo-ionization detector sensor, the PPF sensors were able to detect subtle changes in the concentrations of volatile compounds in indoor air.     

Molecular cloning and characterization of a cDNA encoding ent-cassa-12,15-diene synthase, a putative diterpenoid phytoalexin biosynthetic enzyme, from suspension-cultured rice cells treated with a chitin elicitor

We have isolated and characterized a cDNA encoding a novel diterpene cyclase, OsDTC1, from suspension-cultured rice cells treated with a chitin elicitor. OsDTC1 functions as ent-cassa-12,15-diene synthase, which is considered to play a key role in the biosynthesis of (-)-phytocassanes recently isolated as rice diterpenoid phytoalexins. The expression of OsDTC1 mRNA was also confirmed in ultraviolet (UV)-irradiated rice leaves. In addition, we identified ent-cassa-12,15-diene, a putative diterpene hydrocarbon precursor of (-)-phytocassanes, as an endogenous compound in the chitin-elicited suspension-cultured rice cells and the UV-irradiated rice leaves. The OsDTC1 cDNA isolated here will be a useful tool to investigate the regulatory mechanisms of the biosynthesis of (-)-phytocassanes in rice.     

Plant-growth inhibitory activity of heliannuol derivatives

In addition to (+)-, (-)- and (+/-)-heliannuol E, growth-inhibitory activities of five synthetic chromans and four tetrahydrobenzo[b]oxepins were examined against oat and cress. All heliannuol E isomers exhibited similar biological activities against cress, whereas when tested against oat roots, the unnatural optical isomer (+) showed no inhibitory activity. Four brominated chromans and two tetrahydrobenzo[b]oxepin derivatives also showed apparent inhibition against both cress and oat.