A comparative bioavailability study of a generic capsule formulation containing carbocysteine.

The bioequivalence of two carbocysteine capsulae preparations was assessed in 18 healthy volunteers who received a single 750 mg dose of each carbocysteine formulation, and a new sensitive method for the quantification of carbocysteine in human plasma was developed. The study was conducted using an open, randomized, two-sequence, two-period crossover design with a week washout period between the succesive treatments. Plasma samples were obtained over a 12-hour period and analyzed by high performance liquid chromatography coupled to electrospray ionization-mass spectrometry. Either a multiplicative statistic model for concentration-dependent parameters or an additive approach for time-related parameters were used for the comparison of pharmacokinetic parameters describing both the early and total exposure to carbocysteine. The respective 90% confidence limits [CL] of the individual ratios of geometric means were 0.898 to 1.112 [point estimate 0.999] for Cmax and 0.923 to 1.210 [point estimate 1.057] for AUC(0-infinity), while the difference between times elapsed to reach Cmax was insignificant [p = 0.4497]. Since both 90% CL for the log-transformed AUC(0-infinity) and Cmax geometric mean ratios were included in the proposed 0.80-1.25 interval, test drug (Bronchobos capsules) was considered bioequivalent to the reference one (Mucopront capsules).

Defective protein synthesis of S-30 fraction of reticulocytes of anemic b/b rats.

The preincubated S-30 fraction from reticulocytes of anemic b/b rats is not able to promote the synthesis of proteins in the presence of hemoglobin RNA provided either from the reticulocytes of phenylhydrazine-treated rats or from the reticulocytes of anemic b/b rats. It was observed that poly(U)-directed polyphenylalanine synthesis is negligible in the same system, suggesting the existence of some alteration in regulatory machinery for protein synthesis in the reticulocytes of the anemic b/b rats.

[A computer program for toxico-chemical analysis using gas chromatography]. / Racunarski program za gasnohromatografsku identifikaciju u toksikolosko-hemijskoj analizi.

A high probability of identification of substances containing nitrogen or phosphorus in their molecules is obtained by the original gas chromatographic (GC) system. It enables the reliability of positive identification in 98.43% of cases compared with the modern GC where for the chromatographic library spectrum of 200 substances the probability of identification of unknown substances is only 28.13%. GC system is based on the parallel configuration of the two capillary columns of different polarities connected to the one-column injector and the one nitrogen-phosphorus detector as well as the original computer program developed on the qualitative-logistic approach to interpretation of chromatographic parameters using only one reference substance. The computer program can perform positive logistic identification also in the case when the unknown substance is in the closest chromatographic vicinity, with quite different reference substances on both capillary columns.

[Gas-mass spectrometry in the identification and determination of ethanol in blood]. / Primena gasno-masene spektrometrije u identifikaciji i odredivanju etanola u krvi.

A contemporary analytical method for positive identification and quantitative toxicological--chemical analysis of ethanol in blood samples using the methods of gas extraction, thermal adsorption/desorption and gas-mass spectrometry, was developed. Maximal sensitivity of ethanol detection was 0.27 mmol/l.

Rat b/b anemia: translation of normal and anemic globin mRNA in wheat-germ cell-free system.

Globin mRNAs were isolated from circulating reticulocytes both from rats carrying a homozygous, recessive mutation causing a severe thalassemia-like syndrome and from normal rats. After first identifying the rat globin chains as alpha or beta chains, the translational products primed by both polysomal and nonpolysomal mRNAs in wheat germ 30000 x g supernatant were analyzed: the ratio of alpha to beta globin mRNAs found in polysomes isolated from mutant rats is identical to the ratio of their products synthesized in vivo while the ratio of these mRNAs is quite different in the nonpolysomal fraction, the latter being enriched in alpha globin mRNA. No difference is found in the ratio of alpha and beta globin mRNAs in the polysomal and nonpolysomal RNA isolated from normal rats, both being identical to the ratio of their products synthesized in vivo. One third of the total amount of mRNA found in mutant cells is not in polysomes as compared to only 6 percent for the mRNA from normal lysates. These results suggest that a translational control mechanism is involved although the decreased globin synthesis in b/b anemia can not be fully accounted for by its operation.