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Polyadenylic-polyuridylic acid is a non-toxic double stranded complex of synthetic polyribonucleotides and a proved potent modulator of both humoral and cellular immune responses. The complex is also an inducer of interferon. Although results of direct determination of interferon in patients receiving the complex were negative,' in later studies we found an enhancement of interferon mediated protein kinase p67 K in mouse plasma and p72 K in human plasma in response to treatment with polyadenylic-polyuridylic acid.5 We have also reported that treatment of tumour bearing mice with the complex in association with cyclophosphamide results in a synergistic inhibition of tumour characterised by more retarded tumour growth, lower mortality, and a higher rate of tumour free survival than in mice treated with either agent alone. Furthermore, in these tumour bearing mice receiving such combined treatment there was a significant enhancement of natural killer (NK) cell activity.6 Recently we have studied in more detail the NK boosting effect of polyadenylic-polyuridylic acid in mice in parallel with an assay of an enzyme marker for the production and action of interferon-namely, 2-5 A synthetase. Enhanced NK cell activity accompanied increased activities of 2-5 A synthetase in mice treated with polyadenylic-polyuridylic acid.7 In patients an increase of NK cell activity as well as an increase of 2-5 A synthetase activity after one intravenous injection of 60 mg polyadenylic-polyuridylic acid was also observed (A G Hovanessian et al, paper in preparation). In view of these observations we hypothesise that interferon and NK cell activity probably play a part in the overall mechanism of action of polyadenylic-polyuridylic acid as an adjunct to surgery in breast cancer.Polyadenylic-polyuridylic acid appears to interact with many cell populations,8 so that its biological activity might therefore be exerted at different levels. Indeed, in patients 24 hours after a single intravenous injection of 30 mg of the complex we observed that the mean percentage of E rosette forming cells was significantly (p <0 001) higher than that found before the injection (60-8% v 51-0%), confirming our observation on T lymphocytes in mice.9The relevance of the biological effects to the therapeutic action so far observed remains to be determined. Reports suggest that the low incidence of ischaemic heart disease in Greenlandic Eskimos is related to the effect of a diet rich in eicosapentaenoic acid on platelet reactivity and plasma lipid concentrations. A double blind randomised investigation was therefore conducted of the effects on blood viscosity of dietary supplementation with an oil rich in this fatty acid (1-8 g/day, given as fish oil) and an eicosapentaenoic acid poor oil (as corn/olive oil)

The thermal decomposition of ozone in argon and nitrogen inert gases has been studied in a shock tube. The important reactions are R 1 and R3. R1, R2 R3 M + 0,j .% M -/ -0 2 + 0 0 + 0 3 --+ 0 2 + 0 2 I n the concentration and temperature range studied-argon 0.00334 to 0.0264 mole/l., 769 to 910°K.; nitrogen 0,00902 to 0.01286 mole/l., 689 to 863"K-Rl is a unimolecular reaction a t its low pressure second order limit with k l N t / k l A = kaNr/ kz.4 = 1.64 & 0.1'7. Combining the shock tube data for M = NZ with data in the range 303 t o 383'K.. due to Glissman and Schumacher and reinterpreted by Benson and Axworthy, gives k1y2 = (5.8 f 0.6) X 10" exp( -23,150 Z!C 300/RT)(mole/ L)-l sec.-l and k2x2 = (9.4 i 1 ) X lofi exp(f1700 =I= 300/RT) = 2.0 X lo7 (1000/T)1~66(mole/l.)-2 sec.-l. The kl d a t a are discussed in terms of the Slater and Hinshelwood-Rice-Ramsperger-Kassel ( H R R K ) theories. Interpretation of the data by the classical H R R K theory gives 2.83 =k 0.2 effective oscillators and a collision efficiency of 0.039. The values of k3 obtained are consistent with an extrapolation of previous low temperature data. Vibrationally excited oxygen molecules with from 10 t o 17 vibrational quanta, produced by the strongly exothermic R3 involving O( 3P) atoms, were detected by flash absorption spectra.Introduction Several investigations have been made of the thermal decomposition of ozone, from slightly above room temperature to 5GS'K. Without attempting a discussion of all this work3 and of the evolution of thought regarding the mechanism, we follow Benson and Axworthy4 in accepting reactions R1, R2 and R3 as providing a satisfactory explanation of the homogeneous thermal decomposition. Reaction R4 is included, although it is unimportant in all previous work and in the present work.

Background: Transcatheter aortic valve replacement (TAVR) has been approved in patients with high or prohibited surgical risk for surgery for treatment of severe symptomatic aortic stenosis. Prospective studies examining the benefits of TAVR in intermediate risk patients are ongoing. Other smaller studies including lower risk patients have been conducted, but further meta-analysis of these studies is required to draw more broad comparisons.Methods: A Medline search was conducted using standard methodology to search for clinical trials and observational studies including intermediate risk patients. We limited our meta-analysis to studies matching patient populations by propensity scores or randomization and examined clinical outcomes between TAVR and surgical aortic valve replacement (SAVR). Conclusions: We conclude that in intermediate risk patients undergoing aortic valve replacement, the risk of mortality, neurological outcomes, and MI do not appear to be significantly different between TAVR and SAVR. However, there appears to be a significant reduction in risk of acute renal failure at the expense of an increased risk of requiring a permanent pacemaker in low and intermediate risk patients undergoing TAVR compared to SAVR.

Heat capacity measurements have been made over the temperature range 15–300°K for uranium metal, uranium trioxide, and uranium dioxide. A maximum was observed at 28.7°K in the heat capacity curve of UO2 which is probably the result of the changing population of the magnetic quadrivalent uranium ions among their available energy states. The entropies of these substances at 298.16°K are 12.03, 23.57, and 18.63 cal deg−1 mole−1, respectively. The free energies of formation of UO3 and UO2 are −273.1±3 and −246.6±0.6 kcal mole−1, respectively.

Equilibrium total pressures over the named solid systems were obtained in a static system. Simultaneous establishment of equilibrium (4) by platinum black catalyst mixed with the solids allows the data to be represented in terms of the equilibria (1), (2), and (3). Bi2(SO4)3=β-Bi2O(SO4)2+SO3, (1) ΔH°=38.39,  ΔS°=43.9,  Tm=785, Bi2(SO4)3=α-Bi2O(SO4)2+SO3, (2) ΔH°=33.71,  ΔS°=38.1,  Tm=760, β-Bi2O(SO4)2=Bi2O2SO4+SO3, (3) ΔH°=41.93,  ΔS°=37.3,  Tm=950, SO3=SO2+1/2 O2. (4) The enthalpy (kcal mol−1) and entropy changes (cal K−1 mol−1) are assigned to the middle of the range of temperatures covered Tm (K). The unusually sluggish transformation between the low temperature α and a new high temperature β form of Bi2O(SO4)2 allowed equilibrium pressures for equilibrium (1) to be determined below the transformation temperature Tt, where the β form is metastable, as well as above Tt. Pressure data for equilibria (1) and (2) gave Tt=811±2 K. Annealing-x-ray diffraction methods gave Tt=808±3 K. The entropy change for the transformation is rather large (5.76±0.13 cal K−1 mol−1). The possible nature of the transformation is considered.

This ppper presents the results of a calorimetric investigation of carbonyl chloride covering the range from 15°K. to its boiling point. A comparison of the entropy calculated from molecular data with the entropy change obtained from the XT Cp din T leads to the conclusion that the planar phosgene molecule shows a nearly complete lack of discrimination between the positions of oxygen and chlorine in the crystal lattice.