A novel ascorbic acid-resistant nitroxide in fat emulsion is an efficient brain imaging probe for in vivo EPR imaging of mouse

The loss of paramagnetism of nitroxide radicals due to reductant reactions in biological systems, places a fundamental time constraint on their application as an imaging probe in in vivo EPR imaging studies. However, in vitro studies of the newly synthesized tetraethyl-substituted piperidine nitroxide radical demonstrated high resistivity to paramagnetic reduction when exposed to ascorbic acid, a common reduction agent in biological systems. In this work we investigated the use of these nitroxides as an imaging probe in EPR imaging of small rodents. 2,2,6,6-Tetraethyl-piperidine nitroxide (TEEPONE) is not highly soluble in aqueous media, thus a lipid-based emulsion system of lecithin was used to solubilize TEEPONE. The obtained solution was homogenous and with low viscosity, allowing smooth intravenous injection into mice tail vein. Acquired three dimensional (3D) EPR images of mouse head clearly showed TEEPONE distributed in all tissues including brain tissues, with an average measurable signal half-life of more than 80 min, thus demonstrating high resistivity to reduction due to ascorbic acid in in vivo animal studies, and the potential for use of this compound in in vivo studies of animal model systems.     

Integumental reddish-violet coloration owing to novel dichromatic chromatophores in the teleost fish, Pseudochromis diadema

In the reddish-violet parts of the skin of the diadema pseudochromis Pseudochromis diadema, we found novel dichromatic chromatophores with a reddish pigment and reflecting platelets. We named these novel cells 'erythro-iridophores'. In standard physiological solution, erythro-iridophores displayed two hues, red and dark violet when viewed with an optical microscope under ordinary transmission light and epi-illumination optics, respectively. Under transmission electron microscopy, however, we observed no typical red chromatosomes, i.e., erythrosomes, in the cytoplasm. High-performance thin-layer chromatography (HPTLC) analysis of the pigment eluted from the erythro-iridophores indicated that carotenoid is the main pigment generating the reddish color. Furthermore, when the irrigating medium was a K(+)-rich saline solution, the color reflected from the erythro-iridophores changed from dark violet to sky blue, but the red coloration remained. The motile activities of the erythro-iridophores may participate in the changes in the reddish-violet shades of the pseudochromis fish.     

Chitin-Induced Gene Expression in Secondary Metabolic Pathways of Streptomyces coelicolor A3(2) Grown in Soil

Microarray analyses revealed that the expression of genes for secondary metabolism together with that of primary metabolic genes was induced by chitin in autoclaved soil cultures of Streptomyces coelicolor A3(2). The data also indicated that DasR was involved in the regulation of gene expression for chitin catabolism, secondary metabolism, and stress responses.     

Affinity purification and characterization of a biodegradable plastic-degrading enzyme from a yeast isolated from the larval midgut of a stag beetle, Aegus laevicollis

Two yeast strains, which have the ability to degrade biodegradable plastic films, were isolated from the larval midgut of a stag beetle, Aegus laevicollis. Both of them are most closely related to Cryptococcus magnus and could degrade biodegradable plastic (BP) films made of poly(butylene succinate) (PBS) and poly(butylene succinate-co-adipate) (PBSA) effectively. A BP-degrading enzyme was purified from the culture broth of one of the isolated strains employing a newly developed affinity purification method based on the binding action of the enzyme to the substrate (emulsified PBSA) and its subsequent degradative action toward the substrate. Partial amino acid sequences of this enzyme suggested that it belongs to the cutinase family, and thus, the enzyme was named CmCut1. It has a molecular mass of 21 kDa and a degradative activity for emulsified PBSA which was significantly enhanced by the simultaneous presence of Ca²⁺ or Mg²⁺ at a concentration of about 2.5 mM. Its optimal pH was 7.5, and the optimal temperature was 40 °C. It showed a broad substrate specificity for p-nitrophenyl (pNP)-fatty acid esters ranging from pNP-acetate (C2) to pNP-stearate (C18) and films of PBSA, PBS, poly(ε-caprolactone), and poly(lactic acid).     

Combination with a Defucosylated Anti-HM1.24 Monoclonal Antibody plus Lenalidomide Induces Marked ADCC against Myeloma Cells and Their Progenitors

The immunomodulatory drug lenalidomide (Len) has drawn attention to potentiate antibody-dependent cellular cytotoxicity (ADCC)-mediated immunotherapies. We developed the defucosylated version (YB-AHM) of humanized monoclonal antibody against HM1.24 (CD317) overexpressed in multiple myeloma (MM) cells. In this study, we evaluated ADCC by YB-AHM and Len in combination against MM cells and their progenitors. YB-AHM was able to selectively kill via ADCC MM cells in bone marrow samples from patients with MM with low effector/target ratios, which was further enhanced by treatment with Len. Interestingly, Len also up-regulated HM1.24 expression on MM cells in an effector-dependent manner. HM1.24 was found to be highly expressed in a drug-resistant clonogenic “side population” in MM cells; and this combinatory treatment successfully reduced SP fractions in RPMI 8226 and KMS-11 cells in the presence of effector cells, and suppressed a clonogenic potential of MM cells in colony-forming assays. Collectively, the present study suggests that YB-AHM and Len in combination may become an effective therapeutic strategy in MM, warranting further study to target drug-resistant MM clonogenic cells.     

The True Cost of Greenhouse Gas Emissions: Analysis of 1,000 Global Companies

This study elucidated the shadow price of greenhouse gas (GHG) emissions for 1,024 international companies worldwide that were surveyed from 15 industries in 37 major countries. Our results indicate that the shadow price of GHG at the firm level is much higher than indicated in previous studies. The higher shadow price was found in this study as a result of the use of Scope 3 GHG emissions data. The results of this research indicate that a firm would carry a high cost of GHG emissions if Scope 3 GHG emissions were the focus of the discussion of corporate social responsibility. In addition, such shadow prices were determined to differ substantially among countries, among sectors, and within sectors. Although a number of studies have calculated the shadow price of GHG emissions, these studies have employed country-level or industry-level data or a small sample of firm-level data in one country. This new data from a worldwide firm analysis of the shadow price of GHG emissions can play an important role in developing climate policy and promoting sustainable development.     

Isolation,Purification, and Properties of Lytic Enzyme from Polysphondylium pallidum Myxamoebae

Two lytic enzymes (enzyme I and enzyme II) that lysed Micrococcus lysodeikticus were isolated from the crude extract of Polysphondylium pallidum myxamoebae grown in the presence of Klebsiella aerogenes by precipitation with protamine sulfate and by chromatography on DEAE-Sepharose CL-6B. Enzyme I was further purified by gel filtration on a Superose12 column, and enzyme II by chromatography on a MonoQ HR 5/5 column and gel filtration on a Superose12 column. Enzyme I was a basic protein, while enzyme II was acidic. The molecular weights of enzyme I and II were about 14,000 and 22,000, respectively by SDS-polyacrylamide gel electrophoresis. Optimum pHs for the activity were 5.0 for enzyme I and between 3.5 and 4.0 for enzyme II. The maximum activity of enzyme I and II was obtained at 65°C and 45°C to 55°C and at ionic strength of 0.0075 to 0.03 and 0.06, respectively. Both enzymes cleaved the glycosidic bond of β(1,4)-N-acetylmuramyl-acetylglucosamine of the cell wall peptidoglycan of Micrococcus lysodeikticus. These results indicate that the two lytic enzymes of Polysphondylium pallidum myxamoebae are N-acetylmuramidases.     

The Oligosaccharides Produced from Sucrose by Dematium pullulans

A tetrasaccharide produced from sucrose by Dematium pullulans was obtained in a crystalline state, and its properties and physical constants were studied. By elementary analysis, molecular weight, tetrazolium test, the Raybin test, aldose value, paper chromatographic examination of partial acid hydrolyzate and enzymic hydrolyzate, periodate oxidation, and molar optical rotation, the crystalline compound was identified as β-fructofuranosyl-1-kestose trihydrate.     

Purification of Cathepsin B from Squid Liver

Cathepsin B [EC 3. 4. 22. 1] from the liver of squid, Dorytheuthis bleekri, was purified by the following steps : homogenization, ammonium sulfate fractionation, CM-cellulose column chromatography and rechromatography, Sephadex G–75 column chromatography and iso-electric focusing. The purified enzyme appears to be homogeneous by polyacrylamide gel electrophoresis at both pH 4.3 and pH 9.5 and has an isoelectric point of 6.8. The molecular weight of the enzyme was determined to be 13,600 by Sephadex G–75 column chromatography. The optimum pH for hydrolysis of α-N-benzoyl-l-argininamide (BAA), α-N-benzoyl-dl-arginine-2-naphthylamide (BANA) was 4.5, and it was 4.2~4.7 for N, N′-dimethyl hemoglobin. The value of Km for the hydrolysis of BANA was estimated to be 1.25 mm.