Behavior of hydroxyproline in the rat lung following exposure to surface dust and industrial ashes

There was analysed, by means of biochemical examinations, the behaviour of hydroxyproline level in the lungs of experimental animals exposed to the action of soil dusts and electroenergetic ashes. 44 female white rats of Wistar strain were used in the experiment. The animals were administered intratracheally 0.2 ml dusts and electroenergetic ashes suspension. After decapitation, prepared material was taken from the left lung. Hydroxyproline determinations were performed according to Prokop's und Undenfried's method modified by Tomaszewski and Hanzlik. 9 months after the administration of the dusts, the contents of hydroxyproline slightly differed from the levels observed in control group.     

Magnetic Alignment in Carps: Evidence from the Czech Christmas Fish Market

While magnetoreception in birds has been studied intensively, the literature on magnetoreception in bony fish, and particularly in non-migratory fish, is quite scarce. We examined alignment of common carps (Cyprinus carpio) at traditional Christmas sale in the Czech Republic. The sample comprised measurements of the directional bearings in 14,537 individual fish, distributed among 80 large circular plastic tubs, at 25 localities in the Czech Republic, during 817 sampling sessions, on seven subsequent days in December 2011. We found that carps displayed a statistically highly significant spontaneous preference to align their bodies along the North-South axis. In the absence of any other common orientation cues which could explain this directional preference, we attribute the alignment of the fish to the geomagnetic field lines. It is apparent that the display of magnetic alignment is a simple experimental paradigm of great heuristic potential.     

Sites of alkylation of poly(U) by agents of varying carcinogenicity and stability of products.

Several alkylating agents of widely varying reported carcinogenicity (dimethylsulfate, diethylsulfate, ethylmethanesulfonate, methylnitrosourea, ethylnitrosourea and ethylnitrosoguanidine) were reacted with poly(U) at pH values ranging from 4.5 to 7.5. All nucleophilic centers (internal phosphate groups, ribose hydroxyls, and O2, N-3 and O4 sites of the uracil base) were found reactive, though to different extents, at neutrality and in slightly acid solution. The distribution of products is a function of the alkylating agent and pH. The nitroso compounds are more reactive toward oxygens than are dialkylsulfates and alkylalkanesulfonates. The ratio of N : O alkyl products is strongly pH dependent, primarily due to the N-3 being most reactive at the higher pH values, while the diester is most reactive at the lower pH values. The extent of reaction of the O2, O4 or 2'-O or ribose is not greatly affected over the pH range tested. At pH 5.0 alkyl ribophosphotriesters mainly lose alchol to re-form a stable phosphodiester. With increasing OH- concentration, the favored reaction is chain scission at the 3'-O-P bond.