1,8-Cineole Ameliorates Steatosis of Pten Liver Specific KO Mice via Akt Inactivation

Hepatocyte-specific Phosphatase and tensin homolog (Pten)-knockout (KO) mice exhibit hepatic lesions analogous to non-alcoholic steatohepatitis (NASH). 1,8-cineole is a monoterpene oxide and it has several biological effects including hepatoprotective effects. In this study we revealed that 1,8-cineole ameliorates NASH of Pten KO mice. Pten KO mice were assigned to a control group without any medication or to a 1,8-cineole group injected with 50 mg/kg i.p. twice per week for eight weeks. At eight weeks, livers from each group were processed to measure triglyceride (TG) content, gene expression analysis, western blot analysis, and histological examination including Oil red O staining. 1,8-cineole ameliorated hepatic steatosis in Pten KO mice, revealed by TG content and Oil red O staining. Moreover, 1,8-cineole downregulated collagen 1a1 expression and improved liver fibrosis. Thus, 1,8-cineole has potential as a candidate to treat NASH by inactivating the Akt/PI3-kinase pathway.     

Reaction Profiles of High Silica MOR Zeolite Catalyzed Friedel–Crafts Acylation of Anisole Using Acetic Anhydride in Acetic Acid

Friedel–Crafts reaction of anisole over high silica mordenite zeolite was investigated. Detailed reaction profiles were obtained using various reaction conditions. In particular, the behavior of acetic anhydride during the reaction and the effect on the hydrophilicity of the mordenite zeolite catalyst were investigated.

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Influence of carbon structure of the anode on the production of graphite in single-walled carbon nanotube soot synthesized by arc discharge using a Fe–Ni–S catalyst

We investigated the production of the graphite contained in the soot of single-walled carbon nanotubes (SWCNTs) synthesized using the arc discharge method with a poorly graphitized carbon (PGC) rod in comparison to a graphite rod. A PGC rod was produced using a mixture of coal tar and carbon black and was heat treated to 1000 °C. The rod was packed with a mixture of iron (Fe), nickel (Ni), sulfur (S), and PGC and used for the production of SWCNT soot using arc discharge. From the results of X-ray diffraction and electron microscopy, the amount of graphite in the SWCNT soot synthesized by PGC rod was lower than that by graphite rod. The production of graphite in the soot was found to be dependent on the carbon structure of the anode and the current density of arc discharge.     

Reductively Induced Catalytic DNA Cleavage of Water Soluble Rh<Superscript>III</Superscript>-Br<Subscript>8</Subscript>TMPyP

Abstract  

The Rh^III(Br₈TMPyP)⁵⁺ showed a catalytic DNA cleavage in the presence of ascorbic acid. The UV–visible, Cyclic Votlammetric (CV) and Electron Spin Resonance (ESR) data confirmed involvement of the reduced form of the Rh^III-Br₈TMPyP, Rh^III(Br₈TMPyP)^4+· radical, in the catalytic cycle. Gel-electrophoresis, results revealed that, Rh^III(Br₈TMPyP)⁵⁺ could cleave DNA at 0.01–0.1 μM levels which is significantly higher than that of other metalloporphyrins.     

Origin of enhanced cold crystallization rate for freeze‐dried poly(L‐lactide) from solutions

Poly(L ‐lactide) (PLLA) freeze‐dried from dilute 1,4‐dioxane solutions exhibited very porous structure composed of thin membranes of which the mean thickness was estimated to be 104–135 nm. Heating measurements of differential scanning calorimetry (DSC) showed that the freeze‐dried PLLA (FDPLLA) exhibits an exothermic peak of cold crystallization at 78–81°C, which is at least 20 K lower than that for a quenched amorphous bulk PLLA. In accord with this, the overall rate of isothermal cold crystallization was revealed to be greater for the FDPLLA than that for the bulk. The origin of such high crystallizability of FDPLLA is attributed to its large surface area where the chain mobility is greater than in the bulk PLLA. The exothermic peak in the DSC trace shifted to a further lower temperature when the FDPLLA is immersed in ligroin (nonsolvent), which also suggests a major role of the free surface in enhancing the cold crystallization rate. On the other hand, the density and the chain conformational feature of the FDPLLA were revealed to be identical to the bulk PLLA. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers.     

Preparation of liposomes modified with lipopeptides using a supercritical carbon dioxide reverse-phase evaporation method

Although liposomes are considered to be one of the most promising carriers for drug delivery systems (DDS), they have drawbacks such as insufficient drug-entrapment efficiency and long-term stability. The objectives of this study are to improve the trapping efficiency by addition of lipopeptides (LPs), and using a supercritical CO(2) reverse-phase evaporation (SCRPE) process, along with incorporation of PEG-modified phospholipids to improve long-term stability. In this study, bovine serum albumin (BSA) was used as a model drug substance for entrapment by liposomes. Improvements in the entrapment efficiency and stability of liposomes were achieved by modification with LPs and use of a SCRPE preparation process. The BSA-entrapment efficiency of liposomes modified with cationic LPs with arginine residues, as a result of their ionic interactions, was six times that of liposomes prepared by the Bangham method. Use of a SCRPE method along with LP modification further enhanced entrapment and enabled spontaneous formation of unilamellar liposomes with long-term stability. Liposomes consisting of DPPC/Chol/C(16)-Arg2/DSPE-PEG2000 (60/30/5/5), with up to 70% entrapment efficiency for BSA and a stability level of 90% for over 40 h, were obtained. DSC and SAXS analyses indicated that certain amounts of LP in the DPPC induced phase-transitional and structural changes in the lamellar membrane, and these changes improved the DDS carrier properties.The SCRPE method provides organic-solvent-free liposomes, and the LPs for the liposome modification are derivatives of amino acids and fatty acids, which are sustainable and biocompatible materials. This study therefore suggests that there are opportunities for the development of novel DDS carriers with excellent performance and which address environmental concerns.     

Physicochemical analysis of liposome membranes consisting of model lipids in the stratum corneum

Lamellar lipid layers in the stratum corneum (SC), the outermost layer of the skin, act as a primary permeability barrier to protect the body. The roles of SC lipid composition and membrane structure in skin barrier function have been extensively investigated using ex-vivo SC samples and reconstructed SC lipids in the form of multi-lamellar lipids or liposomes. The primary lipids, especially ceramide, have been found to be highly important. Atopic dermatitis (AD) is a well-known chronic inflammatory skin disease with immunologic and epidermal abnormalities of the permeability barrier; therefore, a comparison of SC lipids in AD skin with those in normal skin is a promising method to explore the mechanisms of skin barrier function. Here, we focused on the effect of sphingoids (ceramide metabolites and a minor component of the SC lipids) and their content/species on skin barrier function. A significant difference in the leakage ratio was observed between model SC lipid liposomes with a different sphingolipid ratio (sphingosine/sphinganine), with a value of 5.43 for normal skin vs. 14.3 for AD skin. This result shows a good concordance with AD mouse experiments. Therefore, an alteration in the composition of minor SC lipids resulting from a ceramide metabolic abnormality can affect the membrane integrity (i.e., skin barrier function). Small angle X-ray scattering (SAXS) measurements revealed no distinct differences in the SAXS pattern between the 3 models, with all models forming a rigid membrane (i.e., a nearly hydrated solid). According to increasing the temperature, the peaks indicated that the lamellar structures decreased in all models and that the lateral packing of lipids decreased, which suggested annealing or melting of the gel to a liquid crystal, although no distinct phase transition was observed through fluorescence anisotropy measurements. Hence, we assume that the altered sphingoid composition triggers local membrane structural changes (i.e., formation of domains or clusters).     

Catanionic mixtures forming gemini-like amphiphiles

The properties of aqueous mixtures of cationic species with alkyl dicarboxylic acid compounds have been studied. The cationic compounds used in this study were tertiary amine-type N-methyl-N-(2,3-dioxypropyl)hexadecylamine (C16amine) and quaternary ammonium-type N,N-dimethyl-N-(2,3-dioxypropyl)hexadecylammonium chloride (C16Q). The alkyl dicarboxylic acid compounds used were HOOC(CH(2))(10)COOH (C12H) and its sodium salt (C12Na). Three aqueous mixtures were examined in this study: (System I) C16amine + C12H, (System II) C16Q + C12Na, and (System III) C16Q + C12H. The solution pH was set at 12 for System III. The combination of (1)H-NMR and mass spectroscopy data has suggested that a stoichiometric complex is formed in the aqueous solutions at a mole fraction of C12H (or C12Na) = 0.33. Here, the C12H (or C12Na) molecule added to the system bridges two cationic molecules, like a spacer of gemini surfactants. In fact, the static surface tensiometry has demonstrated that the stoichiometric complex behaves as gemini-like amphiphiles in aqueous solutions. Our current study offers a possible way for easily preparing gemini surfactant systems.     

Generation of polyacetylene sulfoxide radicals through spin migration from the main-chain to the sulfoxide moiety in the side chain of poly[p-(n-butylsulfoxide)phenylacetylene] prepared with a [Rh(norbornadiene)Cl]2 catalyst

A phenylacetylene bearing an n-butylsulfoxide group, i.e., p-(n-butylsulfoxide)phenylacetylene (1) was prepared in high yields using the [Rh(norbornadiene)Cl]₂-NEt₃ catalyst in the presence of various solvents under mild conditions. The resulting polymer, poly[p-(n-butylsulfoxide)phenylacetylene] (poly(1)), was characterized in detail by ¹H NMR, ESR, laser Raman, and diffuse reflective UV-vis methods. The data clearly showed that cis-to-trans isomerization of the polymer can be induced when pressure is imposed to the polymer at room temperature, rotationally breaking the cis CC bonds to generate the cis and trans radicals. Further, the spin density in the cis radical was migrated from the main-chain to the sulfoxide moiety as the side chain of the phenyl ring to magnetically interact with the first two methylene protons in the n-butyl group giving a triplet line ESR spectrum with an extremely large g value, g = 2.0081.     

Antioxidant and anticancer properties of metalloporphyrins embedded in liposomes

Reactive oxygen species (ROS) are implicated in many disease such as inflammation, arteriosclerosis, cancer. Therefore, a water-soluble cationic metalloporphyrins with SOD activity are studied widely as antioxidant drugs. Further, liposomes are applied to drug delivery system (DDS) as drug carriers and investigated for example disposition and stability. We designed PEG modified liposomes for avoiding reticuloendothelial system (RES) and embedded cationic metalloporphyrins for DDS, evaluated antioxidant and anticancer property. Preservation of these particle size measured DLS in an in vitro system, in order to simulate in vivo conditions of flow. Result of this measurement, we found Pluronic F-68/ liposomes have a long circulation property, and avoid fusion with plasma protein. SOD activity was determined by the stopped-flow analysis and cytochrome c assay, which allowed the evaluation of k(cat) and IC(50) for the reaction with a superoxide anion radical (.O(2)(-)). Anti cancer property was measured by cell viability test. We found that F-68/ liposomes were the most effective catalyst as antioxidant and anticancer. These results revealed that porphyrin-embedded PEG-liposomes had the property of long circulation in blood and that this compound was effective as a SOD model compound with a drug carrier capacity.