Anti-allergic activity of Glycopeptide isolated from Perilla frutescens BRITTON

The anti-allergic activity of Perilla glycopeptide (Pe-GP) isolated from dried Perilla frutescens BRH-TON leaves was investigated. Pe-GP was found to be effective in inhibiting histamine release from IgE-sensitized rat peritoneal mast cells induced by a specific antigen. The histamine release induced by several substances such as concanavalin A, compound 48/80, mastoparan, and ionophore A23187, was also found to be inhibited by Pe-OP. These results suggest that Pe-GP mainly interrupts a pathway of histamine release after calcium influx. Anti-allergic activity of Pe-GP was investigated by ear-swelling response in mice that had been passively sensitized with IgE via intravenous injection. Pe-GP, injected intraperitoneally before exposure to the antigen, was found to inhibit the allergic response in a dosedependent manner (5-100 mg/kg). Pe-GP shows promise as an anti-allergic substance for medical use as well as in health foods. シソ(Perilla frutescens B_)葉熱水抽出液から分離精製されたシソ糖ペプチド(Pe-GP,6kDa)の抗アレルギー活性を検討した。Pe-GPは,ラット腹腔内より単離してIgEで感作したマスト細胞において,特異抗原で刺激したときに誘発されるヒスタミン遊離反応を抑制した。同様にPe-GPはconcanavalin A,compound48/80,mastoparan,ionophore A23187などの誘発するヒスタミン遊離反応も抑制した。これらの結果からPe-GPはヒスタミン遊離機構のうちカルシウム動員以降の経路を主として抑えると考えられる。Pe-GPの生体内における抗アレルギー活性は,IgEを静注して受動感作したマウスの耳介浮腫反応により検討した。抗原塗布前にあらかじめ腹腔内に投与しておくと,Pe-GPは5-100mg/mlの範囲で濃度依存的に浮腫を抑制し抗アレルギー活性を示した。Pe-GPの抗アレルギー活性を有する医薬品としての開発が,健康食品と同様,期待される

The Subaru Deep Field Project: Lymanα\alpha Emitters at Redshift of 6.6

We present new results of a deep optical imaging survey using a narrowband filter ($NB921$) centered at $\lambda =$ 9196 \AA ~ together with $B$, $V$, $R$, $i^\prime$, and $z^\prime$ broadband filters in the sky area of the Subaru Deep Field which has been promoted as one of legacy programs of the 8.2m Subaru Telescope. We obtained a photometric sample of 58 Ly$\alpha$ emitter candidates at $z \approx$ 6.5 -- 6.6 among $\sim 180$ strong $NB921$-excess ($z^\prime - NB921 > 1.0$) objects together with a color criterion of $i^\prime - z^\prime > 1.3$. We then obtained optical spectra of 20 objects in our $NB921$-excess sample and identified at least nine Ly$\alpha$ emitters at $z \sim 6.5$ -- 6.6 including the two emitters reported by Kodaira et al. (2003). Since our Ly$\alpha$ emitter candidates are free from strong amplification of gravitational lensing, we are able to discuss their observational properties from a statistical point of view. Based on these new results, we obtain a lower limit of the star formation rate density of $\rho_{\rm SFR} \simeq 5.5 \times 10^{-4}$ $h_{0.7}$ $M_\odot$ yr$^{-1}$ Mpc$^{-3}$ at $z \approx 6.6$, being consistent with our previous estimate. We discuss the nature of star-formation activity in galaxies beyond $z=6$.Comment: 49 pages, 16 figures, PASJ, Vol. 57, No. 1, in pres

Aseptic Meningoencephalitis Complicated by Retrobulbar Neuritis

A 25-year-old man was admitted to our hospital for testing and follow-up of aseptic meningoencephalitis. After admission to our hospital, the patient suddenly complained of visual field disorder and a decrease of visual acuity in the right eye. We diagnosed aseptic meningitis complicated by retrobulbar neuritis using MRI. We immediately initiated weekly steroid pulse therapy, and eventually, marked improvement in visual acuity and the visual field disorder was observed without any late effects

Nascentome Analysis Uncovers Futile Protein Synthesis in Escherichia coli

Although co-translational biological processes attract much attention, no general and easy method has been available to detect cellular nascent polypeptide chains, which we propose to call collectively a “nascentome.” We developed a method to selectively detect polypeptide portions of cellular polypeptidyl-tRNAs and used it to study the generality of the quality control reactions that rescue dead-end translation complexes. To detect nascent polypeptides, having their growing ends covalently attached to a tRNA, cellular extracts are separated by SDS-PAGE in two dimensions, first with the peptidyl-tRNA ester bonds preserved and subsequently after their in-gel cleavage. Pulse-labeled nascent polypeptides of Escherichia coli form a characteristic line below the main diagonal line, because each of them had contained a tRNA of nearly uniform size in the first-dimension electrophoresis but not in the second-dimension. The detection of nascent polypeptides, separately from any translation-completed polypeptides or degradation products thereof, allows us to follow their fates to gain deeper insights into protein biogenesis and quality control pathways. It was revealed that polypeptidyl-tRNAs were significantly stabilized in E. coli upon dysfunction of the tmRNA-ArfA ribosome-rescuing system, whose function had only been studied previously using model constructs. Our results suggest that E. coli cells are intrinsically producing aberrant translation products, which are normally eliminated by the ribosome-rescuing mechanisms

The Phosphodiesterase-5 Inhibitor Vardenafil Is a Potent Inhibitor of ABCB1/P-Glycoprotein Transporter

One of the major causes of chemotherapy failure in cancer treatment is multidrug resistance (MDR) which is mediated by the ABCB1/P-glycoprotein. Previously, through the use of an extensive screening process, we found that vardenafil, a phosphodiesterase 5 (PDE-5) inhibitor significantly reverses MDR in ABCB1 overexpressing cancer cells, and its efficacy was greater than that of tadalafil, another PDE-5 inhibitor. The present study was designed to determine the reversal mechanisms of vardenafil and tadalafil on ABC transporters-mediated MDR. Vardenafil or tadalafil alone, at concentrations up to 20 µM, had no significant toxic effects on any of the cell lines used in this study, regardless of their membrane transporter status. However, vardenafil when used in combination with anticancer substrates of ABCB1, significantly potentiated their cytotoxicity in ABCB1 overexpressing cells in a concentration-dependent manner, and this effect was greater than that of tadalafil. The sensitivity of the parenteral cell lines to cytotoxic anticancer drugs was not significantly altered by vardenafil. The differential effects of vardenafil and tadalafil appear to be specific for the ABCB1 transporter as both vardenafil and tadalafil had no significant effect on the reversal of drug resistance conferred by ABCC1 (MRP1) and ABCG2 (BCRP) transporters. Vardenafil significantly increased the intracellular accumulation of [3H]-paclitaxel in the ABCB1 overexpressing KB-C2 cells. In addition, vardenafil significantly stimulated the ATPase activity of ABCB1 and inhibited the photolabeling of ABCB1 with [125I]-IAAP. Furthermore, Western blot analysis indicated the incubation of cells with either vardenafil or tadalafil for 72 h did not alter ABCB1 protein expression. Overall, our results suggest that vardenafil reverses ABCB1-mediated MDR by directly blocking the drug efflux function of ABCB1

Observations on Variation in the Ornamental Flowers of Hydrangea macrophylla

Abstract Variation in the ornamental flowers of Hydrangea macrophylla (Thunb.) Ser. in wild populations at Jogasaki on the east coast of the Izu Peninsula, Honshu, Japan, is reported. Forma macrophylla, which was known only in cultivation, was found growing in the wild. Two forms with peculiar features are described as new forms, f. isobue and f. isonotaki

Membrane Protein Degradation by FtsH Can Be Initiated from Either End

FtsH, a membrane-bound metalloprotease, with cytoplasmic metalloprotease and AAA ATPase domains, degrades both soluble and integral membrane proteins in Escherichia coli. In this paper we investigated how membrane-embedded substrates are recognized by this enzyme. We showed previously that FtsH can initiate processive proteolysis at an N-terminal cytosolic tail of a membrane protein, by recognizing its length (more than 20 amino acid residues) but not exact sequence. Subsequent proteolysis should involve dislocation of the substrates into the cytosol. We now show that this enzyme can also initiate proteolysis at a C-terminal cytosolic tail and that the initiation efficiency depends on the length of the tail. This mode of degradation also appeared to be processive, which can be aborted by a tightly folded periplasmic domain. These results indicate that FtsH can exhibit processivity against membrane-embedded substrates in either the N-to-C or C-to-N direction. Our results also suggest that some membrane proteins receive bidirectional degradation simultaneously. These results raise intriguing questions about the molecular directionality of the dislocation and proteolysis catalyzed by FtsH