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L J Berry

Publications and source records attributed to L J Berry.

At least 73 records · Page 4Linked to original sources
PubMed1971

Serum-mediated resistance induced with immunogenic preparations of Salmonella typhimurium.

Serum obtained from animals immunized with attenuated Salmonella typhimurium strain RIA, heat-killed bacterial suspensions, or immunogenic ribosomal preparations was capable of passively conferring protection on normal recipient mice to challenge infection with virulent S. typhimurium strain SR-11. Protection was measured by the ability of a recipient animal to reduce the total number of challenge organisms significantly below that found in challenged control mice. Intraperitoneal administration of 0.1 ml of pooled sera was more effective than 0.05 ml in transferring resistance. The transfer of equivalent amounts of immune serum subcutaneously did not result in demonstrable resistance. In all cases in which serum transfer was effective, resistance was maximal at 5 days, greatly diminished by 10 days, and gone by 15 days post-transfer. Pooled serum obtained from normal donor mice or 0.2 ml of serum from mice hyperimmunized with immunogenic ribonucleic acid preparations did not possess the capacity to confer demonstrable resistance on normal recipients.

Animals↗
PubMed1971

Cell-mediated resistance induced with immunogenic preparations of Salmonella typhimurium.

Peritoneal cells obtained from mice immunized 15 or 30 days previously with (i) 0.1 LD(50) of attenuated Salmonella typhimurium (RIA), (ii) 20 mug (dry weight) of heat-killed Salmonella (SR-11), (iii) 20 mug (dry weight) of immunogenic ribosomal subfractions, or (iv) 20 mug of ribonucleic acid (RNA) subfractions were passively transferred to normal unimmunized mice. The ability of the recipient animals to inhibit or retard the multiplication of virulent challenge S. typhimurium 5 days post-infection was determined by pathogen counts on the carcasses. Peritoneal cells from donors immunized with the RIA, ribosomal, or RNA preparations (i) conferred maximal resistance to challenge 10 to 15 days after cell transfer and demonstrable resistance throughout the 45-day assay period, (ii) conferred resistance to infection when 10(5), 10(3), or 10(2) peritoneal cells were injected subcutaneously but not with fewer than 10(5) cells administered intraperitoneally, and (iii) rendered recipients capable of acting as donors of peritoneal cells that conferred demonstrable resistance on normal recipients. Recipients of peritoneal cells obtained from donors immunized with heat-killed bacteria were unable to (i) significantly inhibit bacterial proliferation at 10 days post-transfer, (ii) resist infection by a challenge inoculum greater than 50 LD(50), and (iii) secondarily confer resistance on normal animals through the passive transfer of cells or serum.

Animals↗
PubMed1970

Immunogenicity of Ribonucleic Acid Preparations Obtained from Salmonella typhimurium.

Mice immunized with purified whole-cell ribonucleic acid (RNA), RNA from the bacterial "particulate" fraction, and ribosome-associated RNA obtained from Salmonella typhimurium were found to be resistant to subsequent challenge infection with virulent salmonellae. Chemically, the immunogenic nucleic acid fractions contained from 1 to 3% "contaminant" material defined (based on the mean of 19 different preparations) as protein (0.24%), deoxyribonucleic acid (0.43%), methyl pentose (0.64%), hexose (1.58%), and undefined carbohydrate (0.76%). Heptoses and lipoidal material were not detectable in any of the immunogenic preparations examined. Physically, the nucleic acid preparations, after analytical ultracentrifugation, exhibited three boundaries similar to those reported elsewhere in comparable systems: 4 to 5S, 16S, and 23S. An evaluation of the immunity induced by the ribosome-associated RNA established that the immune response was (i) comparable to that induced 15 days postimmunization with live salmonellae and by ribosomal vaccines, but greater at 30 days postimmunization than that in mice immunized with attenuated salmonellae; (ii) dependent on the quantity of immunogen administered; (iii) dependent on the size of the infective inocula; (iv) inhibited at 15 but not at 30 days postimmunization when the immunogenic nucleic acid preparations were incorporated into Freund's incomplete adjuvant, (v) reduced or lost by dialysis in relatively high or low immunizing doses, respectively; and (vi) unaffected by enzymatic treatment of the preparations with trypsin, deoxyribonuclease, Pronase plus pancreatic ribonuclease, or pancreatic ribonuclease alone. The possible mode of action of ribosome-associated RNA in inducing an immune response to subsequent challenge infection with the homologous organism is discussed.

Journal Article↗
PubMed1969

Effect of endotoxin and cortisone on synthesis of ribonucleic acid and protein in livers of mice.

The effect of cortisone and endotoxin, singly and in combination, on ribonucleic acid (RNA) synthesis in livers of adrenalectomized mice was determined. This was accomplished by measuring the incorporation either of inorganic (32)P or of (14)C-orotic acid into the RNA. Under similar conditions, the effect of these agents on the rate of protein synthesis was examined with the use of (14)C-leucine. Bacterial endotoxin was found to augment the uptake of isotope in the RNA and in the protein of the liver. These reactions did not appear to be mediated via the pancreatic hormone insulin, which was found to depress the incorporation of the radioactive compounds into RNA. Cortisone increased the uptake of isotope in liver RNA but depressed the incorporation of leucine into hepatic protein. These results indicate that the previously observed ability of endotoxin to prevent the hormone induction of hepatic enzymes, such as tryptophan oxygenase, is not associated with impaired synthesis of liver RNA or protein.

Adrenalectomy↗
PubMed1968

Effect of tryptophan and selected analogues on body temperatur of endotoxin-poisoned mice.

The effect of endotoxin on the body temperature of mice was studied in animals housed without bedding at an environmental temperature of 15 C. Rectal temperatures were measured during the initial 3 to 5 hr of exposure. Doses of endotoxin ranging from 0.01 to 1 ld(50), as determined for mice maintained at 25 C, produce a hypothermia in proportion to dose. Concurrent injection of tryptophan magnified this response in a dose-dependent manner. Cyproheptadine, an antiserotonin drug, antagonized both the hypothermia produced by serotonin alone, and the augmentation of hypothermia produced by tryptophan in endotoxin-poisoned mice. alpha-Methyltryptophan, an analogue of the amino acid that is known to induce tryptophan pyrrolase, also antagonized the increased hypothermia produced by tryptophan. These data support a previous suggestion that inhibition of tryptophan pyrrolase in endotoxin-poisoned mice has the effect of funneling injected tryptophan into the serotonin pathway.

Animals↗
PubMed1968

Role of tryptophan pyrrolase in endotoxin poisoning.

Using substrate induction as a tool, we attempted to determine the role of tryptophan pyrrolase in the response to endotoxin in mice. Previous results have shown that the administration of the ld(50) of endotoxin lowers tryptophan pyrrolase activity. alpha-Methyltryptophan was found to maintain tryptophan pyrrolase activity above control levels in endotoxin-poisoned mice without increasing survival. 5-Hydroxytryptophan, by contrast, lowered tryptophan pyrrolase activity but did not sensitize mice to endotoxin. These results suggest that tryptophan pyrrolase per se does not play a unique role in survival of mice poisoned with endotoxin. This enzyme, however, may reflect the fate of other liver enzymes inducible by adrenocorticoids. In mice given concurrent injections of tryptophan and endotoxin, tryptophan pyrrolase activity was elevated to a level intermediate between that of normal mice and that of mice given tryptophan alone. The mice injected with tryptophan and endotoxin also had about the same mortality as mice given endotoxin alone. Mice treated with tryptophan 4 hr after endotoxin, at a time when the substrate did not fully elevate tryptophan pyrrolase activity, died convulsively and in larger numbers than those given endotoxin alone. This effect was reversed by prior treatment with cyproheptadine, an antiserotonin drug. These results indicate that the depression of tryptophan pyrrolase activity previously observed in vitro after injection of endotoxin reflects an actual decrease in the in vivo activity of the enzyme.

Animals↗
PubMed1968

Inhibition of hepatic enzyme induction as a sensitive assay for endotoxin.

Bacterial endotoxins in mice reduced the induction by cortisone of two hepatic enzymes, tryptophan oxygenase, and phosphoenolpyruvate carboxykinase, they prevented the glyconeogenesis in liver induced by the same hormone, and they induced in intact animals the liver enzyme tyrosine-alpha-ketoglutarate transaminase, all in proportion to their ld(50). When cortisone was given in the least amount (100 mug), it resulted in near maximal induction of tryptophan oxygenase; a smaller amount of endotoxin reduced significantly the level of enzyme than that required when 5 mg of hormone was injected. The smallest amount of endotoxin that prevented tryptophan oxygenase induction was given intravenously to adrenalectomized mice in which 25 mug of cortisone was administered. The amount (0.01 mug) is 1/40,000th of the ld(50). The other metabolic processes subject to alteration by endotoxin required at least 100 to 400 times as much. This property of endotoxin can serve as a sensitive bioassay, although the dose-response curve is steep.

Adrenalectomy↗
PubMed1968

Effect of bacterial endotoxin and inhibitors on tryptophan oxygenase induction in mouse liver slices.

Tryptophan oxygenase activity in mouse liver slices maintained in cluture medium, in Krebs-Ringer bicarbonate solution, or in homologous whole blood declined within 3 hr to about one-half the original level. Actinomycin D and puromycin accelerated the rate of decline, but endotoxin did not. Direct addition of tryptophan to the medium resulted in a higher than normal tryptophan oxygenase activity within 1 hr, and this was maintained well above that of control liver slices up to 6 hr. Triamcinolone, at a dose that doubles tryptophan oxygenase activity in vivo, had no effect on the enzyme in liver slices. Actinomycin and endotoxin did not alter the substrate induction of tryptophan oxygenase; however, puromycin did, but to a limited extent. Liver slices prepared from mice 4 hr after an injection of cortisone had a greater tryptophan oxygenase activity than those of controls. Either endotoxin or actinomycin D resulted in a more rapid decline of the enzyme when added to the slices than was observed in the controls.

Animals↗
PubMed1967

Influence of carbon tetrachloride on inducible liver enzymes and response to endotoxin in mice.

Injection of mice with a sublethal dose of endotoxin 2 hr after administration of 0.1 ml of carbon tetrachloride (CCl(4)) killed 75% of the animals. CCl(4) alone killed no controls. Significant protection against this effect was afforded by 5 mg of cortisone and by 5 mg of nicotinamide adenine dinucleotide (NAD). With a larger dose of endotoxin, cortisone did not give protection. Liver tryptophan pyrrolase activity was lowered 2 hr after CCl(4) injection and reached a minimum after 17 hr. Induction of tryptophan pyrrolase by cortisone, followed by administration of CCl(4), resulted in rapid loss of activity. A significant induction of tyrosine-alpha-ketoglutarate transaminase was observed in CCl(4)-treated mice. The induction of this enzyme by cortisone was somewhat impaired when CCl(4) was administered concurrently with the hormone. CCl(4) did not lower tryptophan pyrrolase in endotoxin-tolerant mice after 4 hr, but at 17 hr the activity was decreased as much as in control mice. Oxidized pyridine nucleotides were decreased 17 hr after administration of CCl(4). This loss was prevented by administration of NAD (5 mg) or by cortisone (5 mg). Carbon clearance from blood was reduced after treatment with CCl(4). These results indicate a degree of similarity between the metabolic effects of endotoxin and CCl(4) in that both depress tryptophan pyrrolase and prevent its induction by cortisone, and both induce tyrosine transaminase in intact mice. Both substances appear to exert these effects through some type of mediated reaction.

Animals↗