Immunization of animals with DNA leads to the production of anti-DNA antibodies (Abs) demonstrating both DNase and RNase activities. It is currently not known whether anti-RNA Abs can possess nuclease activities. In an attempt to address this question, we have shown that immunization of three rabbits with complex of RNA with methylated BSA (mBSA) stimulates production of IgGs with RNase and DNase activities belonging to IgGs, while polyclonal Abs from three non-immunized rabbits and three animals immunized with mBSA are catalytically inactive. Affinity chromatography of IgGs from the sera of autoimmune (AI) patients on DNA-cellulose usually demonstrates a number of fractions, all of which effectively hydrolyze both DNA and RNA, while rabbit catalytic IgGs were separated into Ab subfractions, some of which demonstrated only DNase activity, while others hydrolyzed RNA faster than DNA. The enzymic properties of the RNase and DNase IgGs from rabbits immunized with RNA distinguish them from all known canonical RNases and DNases and DNA- and RNA-hydrolyzing abzymes (Abzs) from patients with different AI diseases. In contrast to RNases and AI RNA-hydrolyzing Abs, rabbit RNase IgGs catalyze only the first step of the hydrolysis reaction but cannot hydrolyze the formed terminal 2',3'-cyclophosphate. The data indicate that Abzs of AI patients hydrolyzing nucleic acids in part may be Abs against RNA and its complexes with proteins.
Microcapsules of ibuprofen were prepared according to the solvent evaporation method, using two coating polymers, cellulose acetate butyrate and ethylcellulose. The influence of two emulsifying agents, polysorbat 80 and polyvinyl alcohol, on the properties of the microcapsules was investigated. The results show that type and concentration of emulsifying agent influences size distribution, drug loading and amount of free drug on the surface of the microcapsules.
Nonspecific nuclease has been isolated from the cells of cyanobacterium Plectonema boryanum and purified to homogenic state. It has been established that the method of centrifugation of cell-free culture extract in the sucrose density gradient is efficient for the separation of pigment proteins and enzyme concentration. Under the successive use of two ion-exchangers the nuclease activity was determined in the concentration range of NaCl 0.065-0.085 M after separation of the cell-free cyanobacterium extract on the column with phosphocellulose in the range of 0.2-0.25 M, on the column with DEAE--Toyopearl respectively. The molecular mass of nuclease which is 40 kDa, has been determined by electrophoresis in polyacrylamide gel under denaturating conditions and gel-filtration on Sephadex G-100. It has been also established that the given enzyme is monosubunitary as to its structure.
When smoking cigarettes under an intense regime with a combination of 100% ventilation blocking and high flow rates, as currently mandated by Health Canada, significant increases in filter temperatures and disproportionately high levels of mainstream smoke water and moisture accumulating in the spent filter were found when compared to other smoking regimes, especially for highly filter ventilated cigarettes. These effects have been reported to decrease cigarette firmness during the course of smoking, to alter filtration properties and efficiencies and to confound the measurement of particulate matter. The high filter temperatures generated also lead to significant amounts of vapour phase compounds desorbing from carbon filters and an over-estimation of the yields of these components. Less adsorption on or more desorption from carbon filters was found for compounds with the highest volatility. Therefore, yield data from the intense regime may not reflect the effectiveness of cigarette design features to reduce certain smoke components that occurs when products are smoked under conditions closer to those used by the majority of smokers in real world situations. In addition, a combination of these interacting factors may explain the worse level of between-laboratory reproducibility data for particulate matter measurement obtained during intense machine smoking. Among-laboratory data variability for vapour phase components, other than carbon monoxide, and for particulate phase components, other than nicotine, still needs to be evaluated in collaborative studies. Before proposing smoking regimes as tools to evaluate smoke emissions, it is essential to understand these various interacting factors and subsequent uncontrolled effects that such regimes can generate and the limitations of their use. These observations imply that higher tolerances may need to be set and taken into account when smoking under the intense regime before deciding that, for a given product, there are real differences between the yields determined in different laboratories.
Tablets containing 91% lactose monohydrate and 4% starch pregelatinized exhibited the best technical properties in comparison to tablets of similar composition with either povidone plus croscarmellose sodium or hydroxypropylcellulose low substituted as binders/disintegrants.
The article presents data on the design of sensitive, selective, useful in group analysis method to detect dimethylsulphide, dimethyldisulphide, acetic, propionic, butyric and valeric acids, methyl alcohol and phenol by means of gas chromatography in the air of cellulose sulphate production working zone. The methods were tested in examining the work conditions in Bratsk found-lavage shops.