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In a phase I safety and immunogenicity study, 112 healthy adult volunteers were randomly allocated to receive a new bivalent (A/Texas/36/91[H1N1-like], B/Harbin/7/94) split virion influenza vaccine propagated in Madin-Darby Canine Kidney cell culture or an identical vaccine manufactured using currently licensed egg propagated virus technology. Soreness at the injection site was common but generally mild (75% of the cell culture-derived vaccine group and 62.5% of the egg-derived vaccine group; p = not significant). General reactions were less common; headache was the most frequently reported adverse effect (26.8 and 30.4%, respectively; p = not significant). Geometric mean haemagglutination inhibition titres post-immunization against the A/Texas strain were 1012 reciprocal dilution in the cell culture-derived vaccine group and 790 in the egg-derived vaccine group; against the B/Harbin strain titres were 420 and 447, respectively (all comparisons, p = not significant). It is concluded that the cell culture-derived split virion influenza vaccine is safe and immunogenic in healthy adult volunteers.

Implantation of MtT-F4 tumor, a mammotropic tumor that secretes large quantities of ACTH, GH and prolactin, into male Fisher rats induced the development of hyperlipidemia. Free fatty acid, triglyceride and cholesterol levels in the plasma were significantly increased at 31 days after tumor implantation. Blood glucose and glycerol levels remained normal, while uric acid concentration in the blood was significantly decreased. The concentrations of the serum lipoproteins were significantly increased, while, only small changes in the distribution of the serum lipids and the composition of the lipoproteins were observed. Following stimulation of isolated adipose tissue cells with ACTH, the lipolytic response and the accumulation of cyclic AMP was higher in cells derived from the rats with the tumor, although the accumulation of cyclic GMP was not different from control adipocytes. Further, when the isolated adipose tissue cells were stimulated with dibutyryl cyclic AMP no difference was observed between the control and tumor bearing groups. Clofibrate administered in the diet resulted in a complete elimination of the tumor effect on serum triglycerides and to a great extent prevented the rise in serum cholesterol. The tumor-induced increase in the concentration of the high density lipoproteins was not affected, but the elevation of the d less than 1.063 lipoproteins was not affected, but the elevation of the d less than 1.063 lipoproteins was partially reversed. The increased lipolytic response and accumulation of cyclic AMP following stimulation by ACTH was not altered in adipocytes derived from tumor bearing rats. However, clofibrate treatment resulted in a significantly greater accumulation of cyclic GMP in fat cells stimulated with ACTH from both control and tumor bearing rats. Clofibrate in the diet did not alter the levels of GH or prolactin or serum lipids in the control rats nor were the elevated hormone levels of the tumor bearing rats changed.

The incorporation of [3H]leucine in vivo into very low density lipoproteins (VLDL) from the rat hepatic Golgi apparatus and serum was studied. A Golgi-rich fraction isolated on a discontinuous sucrose gradient between 0.5 and 1.1 M was found to contain VLDL having common antigenic determinants with serum VLDL. The incorporation of the [3H]leucine into the Golgi VLDL and serum VLDL suggested a precursor–product relationship. Analysis of the apoproteins of the Golgi VLDL by polyacrylamide gel electrophoresis revealed protein bands with similar mobility to those of serum VLDL, except that the former contained virtually no rapidly migrating peptides with the mobility of serum apo-C-II and apo-C-III. The pattern of incorporation of the [3H]leucine into the apoproteins was similar in VLDL from Golgi apparatus and serum, except for the absence of radioactivity in the area of the gel of Golgi apo-VLDL corresponding to apo-C-II and apo-C-III. The radioactive amino acid was incorporated predominantly into the Golgi apo-VLDL bands with similar mobility to apo-B and an apoprotein or group of apoproteins containing the arginine-rich peptide of serum VLDL. In vitro incubation of the Golgi VLDL with [3H]leucine-labeled HDL resulted in the acquisition of a number of proteins, including the rapidly migrating proteins. Administration of colchicine prior to the injection of [3H]leucine resulted in the appearance of gel bands and radioactivity in the apo-C-II and apo-C-III areas of Golgi apo-VLDL, suggesting that these can be acquired if secretion of VLDL is slowed or inhibited. The hepatic Golgi apparatus was then divided into fractions of predominantly forming face (GF3) or secretory granules (GF1). After polyacrylamide gel electrophoresis of the apo-VLDL from GF3, no visible bands or incorporation of [3H]leucine was found in the region of apo-C-II or apo-C-III. However VLDL from GF1 showed visible and radioactive bands in the apo-C-II and apo-C-III area although they represented a much smaller proportion of the total apoprotein than was found in the corresponding serum apo-VLDL. In the isolated perfused liver the percentage incorporation of [3H]leucine into the rapidly migrating apoproteins of Golgi VLDL was considerably less than that found in the corresponding apoproteins of perfusate VLDL, where circulating C lipoproteins are virtually absent.The data indicate that nascent VLDL begins to acquire the C-II and C-III apoproteins during its passage through the Golgi apparatus but that the main acquisition occurs during or after secretion into the space of Disse.

Isolated livers from fed rats were perfused for 1 h with a medium consisting of Krebs–Ringer bicarbonate buffer with added albumin and glucose. Rates of perfusate and bile flow, differences in [Formula: see text], [Formula: see text], and pH, and glucose and potassium efflux were measured. Rewarmed slices of liver taken before the surgical preparation and before the perfusion were found to be able to reverse a cation shift imposed by cold incubation. Slices of liver taken after one perfusion were not able to effect this expected cation transport. It is proposed that the perfusate used was not ideal as evidenced by the altered membrane function of slices after perfusion.

The ability of liver slices prepared from normal rats and from isolated perfused livers following a 1 h control perfusion to reverse a cold-imposed shift in cations when rewarmed was confirmed as a control parameter of rat liver tissue. Three hours after normal rats had received a standard dose of CCl4 via a gastric tube, a decreased ability for the membrane transport of sodium was found. The infusion of CCl4 directly into the perfusate line was shown to cause acute toxic damage in isolated livers. Further, at the end of the 1 h perfusion, the infusion of CCl4 was shown to result in an increased tissue sodium level and a decreased capacity for the membrane transport of sodium and potassium by slices. It is suggested that a generalized change in plasmalemma function, as evidenced in alterations in the membrane transport of cations and tissue cation level, may be an early manifestation of CCl4 hepatotoxicity.

Isolated livers from fed rats were perfused for 1 h with a basic Krebs–Ringer bicarbonate buffer solution containing albumin and glucose and added (1) α-ketoglutarate, (2) pyruvate, fumarate, and glutamate, or (3) washed red blood cells. Perfusate flow rate, [Formula: see text], [Formula: see text], and pH changes across the liver, and glucose efflux in the perfusate, were measured during perfusion. Rewarmed slices of liver taken at the beginning of perfusion were found to be able to reverse a cation shift imposed by cold incubation. Slices of liver taken after 1 h of perfusion were not able to effect this cation shift unless red blood cells were included in the perfusate. It is proposed that noncellular perfusates containing metabolic substrates are not ideal for isolated rat liver perfusion studies as evidenced in the altered membrane transport capacity of slices after perfusion.