An approach for decontamination of beta-lactam antibiotic residues or contaminants in the pharmaceutical manufacturing environment

An effective procedure for decontamination of beta-lactam antibiotic residues or contaminants in the pharmaceutical manufacturing environment was investigated. Decontamination with solutions of hydrochloric acid, sodium hydroxide, hydrogen peroxide and hydroxylamine as agents for degradation was assessed. According to the results, the beta-lactam antibiotics were significantly degraded with sodium hydroxide and hydroxylamine. From the structural analysis of the degradation products of a cephem antibiotic, cefpodoxime proxetil, it was found that hydroxylamine degraded the beta-lactam structure under mild conditions, while sodium hydroxide did not. Therefore, hydroxylamine was considered an appropriate decontamination agent for beta-lactam antibiotics.     

Preparation of zinc oxide nanorods using pulsed laser ablation in water media at high temperature

ZnO columnar single crystals were formed by pulsed laser ablation in deionized water and surfactant aqueous solutions of lauryl dimethylaminoacetic acid (LDA) and cetyltrimethylammonium bromide (CTAB) at 80 degrees C. ZnO particles produced by laser ablation were dissolved at a higher temperature than 60 degrees C, and then crystalline growth to columnar structure proceeded. While large ZnO columnar crystals were obtained in deionized water, the crystals prepared in surfactant solution were smaller than those in deionized water due to inhibition of crystalline growth by surfactant adsorption on ZnO surfaces. The size of ZnO nanorods depended on how surfactant molecules adsorb on ZnO surface.     

Asymptotic expansions and higher order properties of semi-parametric estimators in a system of simultaneous equations

Asymptotic expansions are made for the distributions of the Maximum Empirical Likelihood (MEL) estimator and the Estimating Equation (EE) estimator (or the Generalized Method of Moments (GMM) in econometrics) for the coefficients of a single structural equation in a system of linear simultaneous equations, which corresponds to a reduced rank regression model. The expansions in terms of the sample size, when the non-centrality parameters increase proportionally, are carried out to O(n⁻¹). Comparisons of the distributions of the MEL and GMM estimators are made. Also, we relate the asymptotic expansions of the distributions of the MEL and GMM estimators to the corresponding expansions for the Limited Information Maximum Likelihood (LIML) and the Two-Stage Least Squares (TSLS) estimators. We give useful information on the higher order properties of alternative estimators including the semi-parametric inefficiency factor under the homoscedasticity assumption.     

Photochemical reaction intermediates of benzyl chloride in condensed phase

Reaction intermediates produced upon the photolysis of benzyl chloride have been studied in glassy matrix and in solution. In the steady-state photolysis both benzyl radicals and structural isomers of benzyl chloride were formed in ethanol, while in 3-methylpentane the structural isomers were predominantly formed. The nanosecond laser photolyses of benzyl chloride in ethanol and in cyclohexane also generated benzyl radicals and structural isomers at room temperature. In acetonitrile, in addition to these species, benzyl cations were observed in the early stage after the photolysis.     

Photoinduced electron transfer catalysis of titania particles modified with a Ru(2,2′-bipyridyl)3 2+-grafted polymer by visible light

 The preparation and photocatalysis of colloidal titania modified with Ru(2,2′-bipyridyl)₃ ²⁺-grafted polyacrylate were investigated. Visible light irradiation of the Ru(2,2′-bipyridyl)₃ ²⁺-tethered titania in pH 7.0 buffer solution gave electron transfer to methyl viologen to form the cation radical via electron migration from the Ru(II) complex to the titania surface. Received: 16 September 1999 Accepted: 24 November 1999     

Gas permeation properties of asymmetric carbon hollow fiber membranes prepared from asymmetric polyimide hollow fiber

Asymmetric carbon hollow fiber membranes were prepared by pyrolysis of an asymmetric polyimide hollow fiber membrane, and their mechanical and permeation properties were investigated. The carbon membrane had higher elastic modulus and lower breaking elongation than the polyimide membrane. Permeation experiments were performed for single gases such as H₂, CO₂, and CH₄, and for mixed gases such as H₂/CH₄ at high feed pressure ranging from 1 to 5 MPa with or without toluene vapor. The permeation properties of the carbon membranes and the polyimide membrane were compared. There was little change in the properties of the carbon membranes with a passage of time. The properties were hardly affected by the feed pressure, whether the feed was accompanied with the toluene vapor or not, because the carbon membranes were not affected by compaction and plasticization.     

Characterization of Protein Complexes Containing Nucleoside Diphosphate Kinase with Characteristics of Light Signal Transduction through Phytochrome in Etiolated Pea Seedlings

Abstract— At 5 days after sowing of pea seeds in darkness, intact seedlings were either irradiated with red light for 40 s at 50 μmol/m²/s at the third internode or with red light as above and then with far-red light for 180 s at 0.4 μmol/m²/s, and the stems were sectioned from below the hook (mainly the third internodes) and placed in liquid N₂ in a mortar. The samples were well ground, and after the addition of extraction buffer, homogenates were centrifuged to prepare the crude membrane and soluble fractions. Red-light irradiation increased the phosphorylation of an 18 kDa protein, while far-red-light irradiation decreased it. The 18 kDa protein (formerly 15 kDa protein) was identified as nucleoside diphosphate kinase (EC 2.4.6) (NDP kinase) by western blotting using an NDP kinase-specific antibody. The membrane and the soluble fractions of the red-light-irradiated samples were separated by native polyacrylamide gel electrophoresis. The protein complexes prepared from the membrane and soluble fractions differed in their mobilities, as determined by two-dimensional electrophoresis and nonequilibrium pH gradient electrophoresis. The major protein spots from both samples were cut out from the gel and tested for NDP kinase and protein kinase activity. Both protein preparations showed NDP kinase activity and changes from nucleoside diphosphates and deoxynucleoside diphosphates to nucleoside triphosphates and deoxynucleoside triphosphates in the presence of [γ-³²P]ATP. Both preparations showed protein kinase phosphorylation of myelin basic protein (MBP) rather than histone H1 as protein substrates, suggesting that NDP kinase possesses a function similar to that of MAP kinase.     

Association Between Social Network and Physical Function in Community-Dwelling Older Adults in Japan

Objective: A poor social network and the decline of physical function are known to be critical risk factors for functional decline in older adults. The aim of this study was to investigate the relationships between social network and physical function in Japanese community-dwelling older adults. Methods: Participants were 339 adults aged 65 years or older (mean age : 73.0 years, women :70.2%), living independently in their communities. A self-reported questionnaire was used to assess social network on two different scales―the 6-item Lubben Social Network Scale (6LSNS) and frequency of contact with other people. Handgrip strength, knee extension strength, gait speed, Timed Up and Go Test (TUG) results, and 5-repetition chair stand test (CST) scores were used to determine physical function. A multiple regression analysis that adjusted for confounding factors was used to analyze the relationship between the social network scales and each physical function test. Results: According to the results of a multiple regression analysis, a high 6LSNS score was significantly associated with greater handgrip strength (B = 0.63, p = 0.03), faster CST (B = −0.23, p = 0.01), and faster TUG (B = −0.12, p = 0.03), and high frequency of contact was significantly associated with greater handgrip strength (B = 1.08, p = 0.01). Conclusions: Social network was associated with muscle strength and physical performance. Consequently, older adults with poor social networks require an assessment of physical function, since their physical functions have possibly deteriorated.