Preparation and characterization of gelatin sponge millispheres from air-in-water-in-oil-type emulsions

A novel method for the preparation of gelatin sponge millispheres (GSMs) for biomaterials such as embolic agents and cell scaffolds was developed using an air-in-water-in-oil-type emulsion. The droplets, consisting of a foamy gelatin suspension in caprylic triglyceride, were gelled and rinsed with isopropanol. Sonication and depressurization were used during the rinsing process to create interconnected pores. GSMs cross-links created over 4 h at 155°C without any agent were insoluble and had short and long diameters of 1.1 ± 0.2 mm and 1.3 ± 0.2 mm, respectively. The residual isopropanol and caprylic triglyceride were <0.05% (w/w) and <1% (w/w) respectively. The level of bacterial endotoxins in the extracts was below 0.025 EU/ml, and no bacterial or fungal growth was found during sterility testing. The GSMs produced using this method were considered to meet the basic requirements of embolic agents.     

A long-term degradation study of power generation characteristics of anode-supported solid oxide fuel cells using LaNi(Fe)O3 electrode

The long-term operation of an anode-supported solid oxide fuel cell was examined to study the degradation factor. The cell was constructed using LaNi_0.6Fe_0.4O₃ (LNF), alumina-doped scandia stabilized zirconia (SASZ), and NiO-SASZ as the cathode, electrolyte, and anode respectively. The cell had Pt current collectors and was operated for 6500 h. The test was carried out at 1073 K with a constant load of 0.4 A cm⁻² and included thermal cycling. The cell voltage degradation rate was below 0.86%/1000 h when the cell was operated for up to 5200 h. Changes in the resistance of the cells during the experiments were analyzed by impedance spectroscopy. The cathode polarization resistance and ohmic resistance increased with time. The elements (Si and B) contained in the water condensed from the cathode exhaust gas were identified using inductively coupled plasma (ICP).     

Occurrence of tetrodotoxin and paralytic shellfish poisons in a gastropod implicated in food poisoning in southern Taiwan

The toxicity of the gastropod Nassarius papillosus implicated in a food paralytic poisoning incident in Liuchiu Island, Taiwan, in October 2005 is reported. The symptoms of a victim (67 years old) were featured by general paresthesia, paralysis of phalanges and extremities, paralysis, coma, and aphasia. The remaining specimens of shell were assayed for toxicity. The range of specimen toxicity was found to be 63-474 mouse units (MU) per specimen for N. papillosus by a tetrodotoxin (TTX) bioassay. The mean (SD) toxicity of the digestive gland and other portions were 296 ± 120 and 382 ± 156 MU in N. papillosus. The toxin was partially purified from the acidic methanol extract of the gastropod by using a C18 solid-phase extraction column. The eluate was then filtered through a 3000 MW cut-off ultrafree microcentrifuge filter. It was shown that the toxin purified from gastropods analysed by high-performance liquid chromatography and liquid chromatography/mass spectrometry contained TTX 42-60 µg g^-1 (about 90%), whereas along with minor paralytic shellfish poisons (PSP) it was 3-6 µg g^-1 (about 10%).     

Rational choice of bioactive conformations through use of conformation analysis and 3-way partial least squares modeling

Comparative molecular field analysis (CoMFA) has become widely used in three-dimensional (3D) QSAR studies. Although CoMFA has been of general use, there are some critical problems in the proper application. A major problem of CoMFA, including most other 3D QSAR methodologies, is that the results are dependent on the chosen bioactive conformations and the corresponding alignment rules of molecules. Recently, we have proposed a novel method with a 3-way PLS formulation for solving the conformation/alignment problem in 3D QSAR studies [K. Hasegawa, M. Arakawa, K. Funatsu, Chemom. Intell. Lab. Syst., 47 (1999) 33–40]. The purpose of the present study is to demonstrate the general utility of our approach by applying to a real CoMFA data set. The data set of Protein-Tyrosine Kinase (PTK) inhibitors was used as a test sample. The possible 3D conformations of all molecules were generated by conformational analysis and they were characterized by field variables of CoMFA. To each unique conformation of the most active compound, one sample-variable sheet comprising of the most similar conformations was defined. The 3-way arrays for 3-way PLS analysis were created by collecting all sample-variable sheets. From the regression coefficient values of the 3-way PLS model, conformations largely contributing to inhibitory activity were selected and the resulting final CoMFA model could give the reasonable 3D coefficient contour maps.     

Multi-shot flash lamp annealing method for electroless-plated Ni-P film on UV-surface-modified ABS

The multi-shot flash lamp annealing (FLA) method as a rapid annealing technique was developed for an electroless-plated Ni-P film on UV-surface-modified acrylonitrile–butadiene-styrene (ABS) in place of the conventional annealing method. The new multi-shot FLA method continuously irradiates a Xe flash discharge with low irradiance (<1?J?cm^–2) with a frequency of 3?Hz. An adhesion strength between the electroless Ni-P film and ABS of more than 1.2?kN?m^–1 was achieved in a short time of approximately 30?s; this adhesion strength was larger than that obtained in the conventional method of 1?h duration. The etching effect of the FLA method was assessed by a study of the surface morphologies of the Ni-P films. XRD spectra of the Ni-P films showed an improvement in the crystallinity of the films. Considering surface elemental analyses of the peeled Ni-P-film/ABS, a cohesive failure, which implies high adhesion, was observed in the ABS. The proposed FLA method is expected to efficiently improve the adhesion and significantly reduce the annealing time in the electroless plating process.     

Gas permeability of thin dense films from polymer blend of thermoplastic elastomer and polyolefin

Stretched thin films composed of a thermoplastic elastomer, a polystyrene‐block‐poly(ethylene butylene)‐block‐polystyrene triblock copolymer (SEBS), and polyolefins, poly(ethylene‐co‐ethylacrylate) and poly(ethylene‐co‐propylene), were obtained by blow‐molding, uniaxial stretching, and cooling to room temperature and the gas permeability of the stretched films was investigated. When the as‐blown annealed film was subjected to uniaxial stretching in the machine direction, P_O2 and P_N2 increased with an increase in the stretching ratio K and approached a constant value at high stretching ratios. In addition, P_O2/P_N2 decreased gradually with K and approached a value of 2.95–3.0. The reason for this unique gas permeation behavior is that the molecular mobility of poly(ethylene butylene) chains in a direction normal to the film increases and reaches an equilibrium state at around K = 4.5. The change in gas permeability of the stretched films can be explained using a deformation model for the SEBS matrix. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39386.     

Persulfate-induced photochemical decomposition of a fluorotelomer unsaturated carboxylic acid in water

The persulfate (S(2)O(8)(2-))-induced photochemical decomposition of C(3)F(7)CF=CHCOOH in water was investigated to develop a method to neutralize stationary sources of fluorotelomer unsaturated carboxylic acids (FTUCAs), which have recently been detected in the environment, and are considered to be more toxic than the environmentally persistent perfluorocarboxylic acids (PFCAs). Photolysis of S(2)O(8)(2-) produced highly oxidative sulfate radical anions (SO(4)(-)), which efficiently decomposed C(3)F(7)CF=CHCOOH to F(-) and CO(2) via C(3)F(7)COOH. With an initial S(2)O(8)(2-) concentration of 12.5mM and irradiation from a 200-W xenon-mercury lamp, C(3)F(7)CF=CHCOOH at a concentration of 680muM was completely decomposed within 5min. When 8.00mM S(2)O(8)(2-) was used, the initial rate of C(3)F(7)CF=CHCOOH decomposition induced by 254-nm light irradiation was 45 times as high as that with photolysis alone. The apparent quantum yield for the C(3)F(7)CF=CHCOOH decomposition with 6.25mM S(2)O(8)(2-) and 254-nm light was 2.4, indicating that virtually all SO(4)(-) anions produced by the photolysis of S(2)O(8)(2-) contribute to the decomposition of C(3)F(7)CF=CHCOOH.     

Characterization of a novel methyl-accepting chemotaxis gene, dmcB, from the oral spirochete Treponema denticola

Immediately downstream from the previously isolated Treponema denticola ATCC 35405 prtB gene coding for a chymotrypsinlike protease activity, an open reading frame, ORF3, was identified which shared significant homology with the highly conserved domains (HCDs) of bacterial methyl-accepting chemotaxis proteins (MCPs). Nucleotide sequencing of this ORF revealed that the gene would code for a protein with a size of approximately 41 kDa. In addition, this sequence contained a domain which was virtually identical to the HCD of a recently characterized MCP, DmcA, of strain 35405. Therefore, this ORF was named dmcB. Northern blot analysis suggested that dmcB was part of an operon structure containing prtB. Insertional inactivation of dmcB utilizing an ermF-ermAM cassette resulted in a mutant with decreased chemoattraction toward nutrient supplements. In addition, the mutant displayed an altered pattern of methylated proteins under conditions of chemotaxis. Inactivation of the dmcB gene also attenuated the methylation of the DmcA protein. These results suggest that the dmcB gene codes for an MCP in T. denticola which may interact with other MCPs in these organisms.