The Marquis reaction of morphine (author's transl)

The Marquis Reaction of Morphine From the violet solution of morphine and formaldehyde in 60proc. sulfuric acid the substance I was obtained which gives the characteristic colour with sulfuric acid. The structure of I was elucidated. It arises from 2 molecules morphine and 2 molecules formaldehyde. With sulfuric acid coloured oxonium carbonium ions are formed. In the Marquis reaction apomorphine does not arise.     

Demonstration of glucose-6-phosphatase and peroxisomal catalase activity by ultrastructural cytochemistry in oval cells from livers of carcinogen-treated rats.

Oval cells isolated from livers of carcinogen-treated rats have morphologic and biochemical features of immature hepatocytes but seem to lack glucose-6-phosphatase (G6Pase) activity. The authors reinvestigated this question using histochemical methods for visualization of G6Pase activity by light and electron microscopy and the polyene antibiotic filipin to facilitate the penetration of the substrate. Oval cells that proliferate in the liver of animals receiving a carcinogenic diet (choline-deficient, containing 0.05% ethionine) contained G6Pase activity; 50-60% of nonparenchymal epithelial cells isolated from these livers by centrifugal elutriation contained G6Pase activity; and oval cell cultures displayed intense G6Pase activity at confluence but did not have detectable enzyme activity during exponential growth. These results and the demonstration that clofibrate induces peroxisomal proliferation in cultured oval cells strengthen the view that oval cells (or some subpopulation of cells in this compartment) are part of the hepatocyte lineage.     

Clonal dominance of low-affinity antibodies in rabbit hyperimmune anti-streptococcal group A-variant polysaccharide antisera.

Intraveneous hyperimmunization of selectively bred rabbits with streptococcal group A-variant vaccines elicits antibody responses of restricted heterogeneity at high antibody levels. In these antisera, IgG with dissociation constants Kd = 10(-6) M constitutes 90% and IgG with Kp = 10(-9) M accounts for only 10% of the group A-variant polysaccharide-specific antibodies. The low affinity antibody fraction represents the dominant clonotypes. Preparative isoelectric focusing in granulated (Ultrodex G-75) gels was used to successfully purify single-band material belonging to dominant spectrotypes. Affinity studies with these antibody fractions with the highest reported degree of purity yielded Kd = 10(-6) M values, thus confirming that clonal dominance is exclusively associated with low-affinity antibodies. Since it is known from previous work (M. Cramer and D. G. Braun, Scand. J. Immunol. 1975. 4:63) and from the rabbit antisera used here that clonal dominance of this sort is long-lived, this work fails to support the argument of immune maturation. The data more logically relate to antibodies that emerge with different subspecificities -- recognized in the antigen as a function of time in immunization procedures -- rather than to an inherent property of the immune system.     

Determination of sotalol in human body fluids for pharmacokinetic and toxicokinetic studies using high-performance liquid chromatography

A sensitive, reliable and discriminating assay method is reported for the determination of sotalol (4-(1-hydroxy-2-isopropylaminoethyl)methanesulfonanilide) in human plasma and urine. The assay procedure has been successfully used during pharmacokinetic studies in healthy volunteers and patients as well as during toxicokinetic analysis. For sample preparation the internal standard atenolol was added to the specimen which was then extracted with n-pentanol-chloroform (1/3) at pH 9.0 followed by re-extraction into 0.05 mol/l sulfuric acid. Chromatography with fluorimetric detection was performed on Hypersil ODS 5 micron including the addition of heptanesulfonic acid and sodium dodecyl sulfate to the mobile phase of acetonitrile-water-acetic acid (20/79/1). Calibration was linear over the ranges of 0.1 to 5.0 micrograms/ml and 0.2 to 100 micrograms/ml for plasma and urine, respectively. Over these ranges coefficients of variation were below 10%. Recovery was between 82 and 98% from plasma and between 92 and 99% from urine.     

The glass transition temperatures of homogeneous blends of polystyrene,poly(methyl methacrylate), and copolymers of styrene and methyl methacrylate

The glass transition temperatures T_g of homogeneous binary blends of the homo- and the statistical copolymers of the system poly(styrene-co-methyl methacrylate) were studied. Some of the blends, which are in the equilibrium phase separated, were forced into homogeneity. T_g (?) of the homopolymer blends (PS/PMMA)? follows the Fox equation, while T_g (x) of the pure copolymers P(S_xMMA_{1 ? x}) exhibits a minimum. This minimum can be effectively removed by blending the copolymers with small fractions (? ≈ 0,2) of one of the two homopolymers or a differently composed copolymer P(S_yMMA_{1 ? y}).