Massive haemoptysis death and other morbidity associated with high dose rate intraluminal radiotherapy for carcinoma of the bronchus

Fluctuation analysis allows for the determination of mutation rates in cell cultures in vitro. As originally described by Luria and Delbruck and extended by Lea and Coulson and by Capizzi and Jameson, this analysis has been useful in estimating mutation rates in cultured cells where the frequency of mutational events is low. However. in cultures where high mutation rates and multiple independent mutation events occur, leading to the accumulation of many mutant cells, these standard methods may not apply. Here, we present a new method for the estimation of mutation rates based on the assumption that multiple events may contribute to the accumulation of mutant cells. We compared mutation rates determined by Lea and Coulson's and by Capizzi and Jameson's methods with those determined by our method using experimental and stimulated data from our studies of immunoglobulin gene mutation and isotype switching in B lymphocyte cultures. The three methods resulted in very different calculated rates when many mutants were present in the culture, such as when mutation rates were high, while only small differences in calculated rates were found when mutants were rare. Unlike previous fluctuation analysis calculations, our method is applicable for the estimation of both low and high rates.     

Forskolin stimulation of water and cation permeability in aquaporin 1 water channels

Aquaporin 1, a six-transmembrane domain protein, is a water channel present in many fluid-secreting and -absorbing cells. In Xenopus oocytes injected with aquaporin 1 complementary RNA, the application of forskolin or cyclic 8-bromo- adenosine 3',5'-monophosphate increased membrane permeability to water and triggered a cationic conductance. The cationic conductance was also induced by direct injection of protein kinase A (PKA) catalytic subunit, reduced by the kinase inhibitor H7, and blocked by HgCl2, an inhibitor of aquaporin 1. The cationic permeability of the aquaporin 1 channel is activated by a cyclic adenosine monophosphate-dependent mechanism that may involve direct or indirect phosphorylation by PKA.     

Binding properties of bovine colostral anti-dinitrophenyl (dnp) immunoglobulins g2 (igg2)

The number of combining sites per mole of bovine colostral anti-DNP IgG2 was found to be 2 and the total affinity constant was 0.81 X 10(4) M-1. Unlike bovine colostral IgG1, the nonspecific binding of H3-epsilon-DNP-1-lysine by IgG2 as a function of increased concentrations, did not show a negative, cooperative slope. Spectral measurements made with anti-DNP IgG2 in the reference cell vs. anti-DNP IgG2 plus hapten in the experimental cell revealed a hypochromic, red shift from 363 to 365 nm. If the reference cell contained hapten, a red shift from 280 to 283 nm and an enhancement in the extinction coefficient of IgG2 was observed. These spectral changes were not observed if nonspecific IgG2 was substituted for anti-DNP IgG2 in the experimental cell. The enhancement in the extinction coefficient was interpreted to be due to a possible exposure of previously buried tryosine and tryptophan residues.     

Caffeine-stimulated lipolysis in relation to pathologic pregnancy

In an acute experiment the effect of Coffeinum-Sodium-salicylicum (3 mg/kg body weight) on the parameter of lipolysis Free Fatty Acids (FFA) and free glycerin in early pregnancy is investigated. On the base of literature data the possibility of labour induction due to high blood-values of FFA and glycerin is explained and the importance of the coffeine-stimulated lipolysis in pregnancy is discussed. To prevent one possible cause of abortus or miscarriage it is recommended to restrict taking coffee during pregnancy.     

Cobalt-concanavalin A. An index of inactive and active conformational states

Studies on the circular dichroic spectrum of cobalt-substituted concanavalin A have been continued in particular with respect to calcium- and saccharide-induced spectral pertubations reported previously (Kalb, A.J. and Pecht, I. (1973) Biochim. Biophys. Acta 303, 264-268; Richardson, C.E. and Behnke, W.D. (1976) J. Mol. Biol. 102, 441-451). We find that the addition of calcium or cadmium to (CO2+)-concanavalin A induces slow time-dependent alterations in the extrinsic cotton effects. Moreover, one equivalent of calcium is sufficient to cause maximal changes in the cobalt spectrum provided sufficient time is allowed for the effect to be observed. The addition of mono, di-and trisaccharides, specific for concanavalin A, have no resolvable effect upon the cobalt spectrum of concanavalin A (Richardson, C.E. and Behnke, W.D. (1976) J. Mol. Biol. 102, 441-451). The data presented here suggest that these time-dependent processes are conformationally mediated and occur subsequent to S2 occupancy. Evidence is presented that a particular calcium-cobalt-concanavalin A conformer exists which is responsible for the generation of activity in a light-scattering assay system.     

Nonlactating-cow therapy with a formulation of penicillin and novobiocin: therapeutic and prophylactic effects

An experimental product incorporating 500,000 IU of procaine penicillin G and 600 mg of sodium novobiocin in 2% aluminum monostearate-peanut oil gel (10-ml dose) was infused after the final milk-out at end of lactation into all 4 mammary quarters of 56 cows that were infected in at least 1 quarter. The therapeutic and prophylactic efficacies were published in the companion report. Infusion of the product in all quarters of 5 lactating cows resulted in only slight irritation. Penicillin was eliminated by the 11th milking and novobiocin by the 5th. After infusion in the dry udder, the antibiotics were no longer detectable in serous secretion after 14 days and failed to appear in urine at the earliest (7-day) sampling after administration. Neither antibiotic was detectable in the 1st postpartum milking after nonlactating periods as short as 3 weeks.