Metabolic Changes during Defense Responses against Wound Stresses in Citrus Plants

Citrus plants are well known as a rich source of functional chemicals; however, metabolites involved in defense responses against environmental stresses are not yet well understood. Among environmental stresses, mechanical wounding is a continuous threat toward the growth and survival of plants. Recent advances in analytical technology and informatics enable comprehensive analysis of primary and secondary metabolites. In this chapter, metabolic profiling of leaf metabolites in seven Citrus species during responses against wound stress as well as defense-related phytohormone treatments was described. Moreover, we discussed current metabolomic techniques, application of these techniques to researches on Citrus defense responses and metabolic profiling-oriented identification of novel compounds

Void-induced cross slip of screw dislocations in fcc copper

Pinning interaction between a screw dislocation and a void in fcc copper is investigated by means of molecular dynamics simulation. A screw dislocation bows out to undergo depinning on the original glide plane at low temperatures, where the behavior of the depinning stress is consistent with that obtained by a continuum model. If the temperature is higher than 300 K, the motion of a screw dislocation is no longer restricted to a single glide plane due to cross slip on the void surface. Several depinning mechanisms that involve multiple glide planes are found. In particular, a depinning mechanism that produces an intrinsic prismatic loop is found. We show that these complex depinning mechanisms significantly increase the depinning stress

MicroRNA-125b regulates the expression of aggrecanase-1 (ADAMTS-4) in human osteoarthritic chondrocytes

INTRODUCTION: Increased expression of aggrecanase-1 (ADAMTS-4) has emerged as an important factor in osteoarthritis (OA) and other joint diseases. This study aimed to determine whether the expression of ADAMTS-4 in human chondrocytes is regulated by miRNA. METHODS: MiRNA targets were identified using bioinformatics. Chondrocytes were isolated from knee cartilage and treated with interleukin-1 beta (IL-1β). Gene expression was quantified using TaqMan assays and protein production was determined by immunoblotting. Luciferase reporter assay was used to verify interaction between miRNA and target messenger RNA (mRNA). RESULTS: In silico analysis predicted putative target sequence of miR-125b on ADAMTS-4. MiR-125b was expressed in both normal and OA chondrocytes, with significantly lower expression in OA chondrocytes than in normal chondrocytes. Furthermore, IL-1β-induced upregulation of ADAMTS-4 was suppressed by overexpression of miR-125b in human OA chondrocytes. In the luciferase reporter assay, mutation of the putative miR-125b binding site in the ADAMTS-4 3'UTR abrogated the suppressive effect of miR125. CONCLUSIONS: Our results indicate that miR-125b plays an important role in regulating the expression of ADAMTS-4 in human chondrocytes and this identifies miR-125b as a novel therapeutic target in OA

Spred-2 deficiency exacerbates acetaminophen-induced hepatotoxicity in mice

MAPKs are involved in acetaminophen (APAP)-hepatotoxicity, but the regulatory mechanism remains unknown. Here, we explored the role of Spred-2 that negatively regulates Ras/ERK pathway in APAP-hepatotoxicity. Spred-2 knockout (KO) mice demonstrated exacerbated liver injury, an event that was associated with increased numbers of CD4(+) T, CD8(+) T and NK cells in the liver compared to the control. Levels of CXCL9/CXCL10 that attract and activate these cells were increased in Spred-2 KO-liver. Kupffer cells isolated from Spred-2 KO mice after APAP challenge expressed higher levels of CXCL9/CXCL10 than those from the control. Upon stimulation with APAP or IFN gamma, naive Kupffer cells from Spred-2 KO mice expressed higher levels of CXCL9/CXCL10. NK cell-depletion attenuated APAP-hepatotoxicity with lowered hepatic IFN gamma and decreased numbers of not only NK cells but also CD4(+) T and CD8(+) T cells in the liver. These results suggest that Spred-2 negatively regulates APAP-hepatotoxicity under the control of Kupffer cells and NK cells

Measurements of Cosmic-ray Low-energy Antiproton and Proton Spectra in a Transient Period of the Solar Field Reversal

The energy spectra of cosmic-ray low-energy antiprotons and protons have been measured by BESS in 1999 and 2000, during a period covering the solar magnetic field reversal. Based on these measurements, a sudden increase of the antiproton to proton flux ratio following the solar magnetic field reversal was observed, and it generally agrees with a drift model of the solar modulation.Comment: 4 pages, 4 figures, revised version accepted for publication in Phys. Rev. Let

A New Laundering Method Using Aqueous Solution of High-polymer for Coating of Soiled Fabrics and Followed by Water Laundering

A new laundering method was presented by the author, which may be named provisionally as "Polymer-coated Laundering Method", and by this method, a higher detergency than ordinal laundering methods, i.e. immersion of soiled fabrics in a solution of detergent, was attained. And this method have projected many interesting problems to the physical chemistry of detergency, and have broken the common and fixed idea about laundery and washing. This laundering method was constructed from the following chief process ; soiled fabrics were coated with a solution of high-polymer or the mixture of high-polymer and surfactant, then dried, and laundered in merely water. There were also many variations, for instance, laundering in a solution of detergent and the omission of the drying. Fundamental conditions for this method, such as the amount of used high-polymer, laundering temperature, laundering time and the effect of surfactant were discussed with the soiled cotton fabrics. The effect of drying and its types was also discussed. Then the effect of this laundering method for hydrophobic fibers was compared with hydrophilic cell ulosic fibers. The obtained results of this method have driven off the fixed idea that soiled fabrics and garments must be laundered by the immersion of it in a solution of detergent or organic solvents, and it seems that there might be more variations of laundering method when high-polymers were effectively used

Studies on the Soiling of Fabrics Part 3 : Soiling Characteristics of Sized or Starched Fabrics

各種の糊料ポリマーにより糊付けした木綿布の,3種の方法の人工汚染液による汚染性を比較して,次の如き結果を得た。1)四塩化炭素分散汚染液によつては,部分鹸化ポリビニルアルコール(PVA-Ac)糊付布を除き,それぞれ若干の防汚性を示し,澱粉(S)やポリビニアルコール(PVA)は,ソジウムカルボキシメチルセルロース(SCMC)よりむしろ防汚性が高い。2)PVAの防汚性は重合度が増すとやや減少する傾向を示すが,PVA-Acは重合度が増すと逆に助汚性を減少する。ソジウムカルボキシメチル澱粉は,澱粉糊付布よりも防汚性を上昇するが,その効果はあまり大きくない。3)水分散汚染液によると,1)項とは異なつて,SCMC糊付布が明らかな防汚性を示すが澱粉・PVA・PVA-Ac等による糊付布は原布よりも汚染されやすい。この現象は次報(第4表)に述べる洗浄効果よりみた広義の防汚性とも関連することである。4)水分散汚染液に糊料ポリマーを溶解したもので未糊付布を汚染すると,いずれの糊料を添加した場合でも,無添加の汚染液よりは汚染しやすい。Soiling characteristics of fabrics, especially those of cotton and viscose rayon, were discussed in the previous papers using the artificial soiling mixtures which were dispersions of carbon-black and oily materials (mineral oil and hardened fat) in CCl_4 or in H_2O. The difference of dispersion medium for carbonblack was found as a big factor of soiling and de-soiling behaviour of fabrics. In this paper, soil preventive qualities of some useful sizing materials (starch, carboxymethylcellulose, polyvinylalcohol, alginic acid and several derivatives of those) are compared on the starched or sized cotton fabrics. Methods of artificial soiling and of determination of soiling degree are almost the same as those in the prepvious papers, except "soiling medium of sizing solution", which is the aqueous dispersion of carbon-black containing sizing materials. By the soiling mixture using CCl_4 as dispersion medium for carben-black, the starched cotton fabrics of starch or PVA show soil-preventing character, whereas that of PVA-Ac (partially saponified polyvinylalcohol) are more readily soiled than original fabrics. SCMC siz ed fabrics also prevent to be soiled, but this quality is more remarkable when water is used as dispersion medium than in CCl_4-medium. Fabrics starched by starch, PVA and PVA-Ac have no soil-preventive characteristics in aqueous soiling mixtures