Beta-carotene in tube feeding.

The supplementation of an enteral feeding formula on soya-basis specially designed for geriatric patients with 1,5 mg to 2 mg beta-carotene per day increases its corresponding plasmatic concentration from 20 mcg/L to normal to optimal levels near 500 mcg/L. This intake is much lower than the proposed safe intake of 6-20 mg beta-carotene per day. A close incorporation of beta-carotene in the lipid moiety of the ready-to-use formula might increase its bioavailability. The other anti-oxidative vitamins A and E remain to their respective normal levels at a supplemental daily intake of 2500 IU vitamin A and 12,5 mg vitamin E. The new enteral feeding formula for geriatric patients seems to cover their global nutritional needs.

Absence of complement fixing antibodies against lipopolysaccharides from Escherichia coli in a subgroup of patients with Crohn's disease.

Complement fixing antibodies against different Escherichia coli lipopolysaccharides were determined in patients with Crohn's disease and in healthy individuals and compared with antitetanus toxoid antibodies. All healthy individuals had antilipopolysaccharide antibodies, 10 of 27 patients with Crohn's disease had no antibodies and six had rapidly changing antibody titres. These abnormalities were found in patients with disease in the colon, with arthropathy and fistula. Antilipid A was found at lower titres in Crohn's disease. Neither antitetanus toxoid antibodies, nor immunoglobulin concentrations were different in patients with or without antilipopolysaccharide antibodies. There was no evidence for circulating immune complexes in patients lacking antilipopolysaccharide antibodies. Certain subgroups of patients with Crohn's disease have altered antibody levels to typical enteral antigens which most likely can be explained by local antibody binding to lipopolysaccharides at inflammatory sites, or by changes in immunoregulation in this disease.

Stimulated murine peritoneal macrophages in suspension and cell culture: enzyme determinations by biochemical and histochemical means.

Peritoneal exudate cells of mice were studied up to 4 days after i.p. injection of thioglycollate broth medium by means of conventional enzyme determinations and quantitative histochemical measurements of individual cells. Cells from the peritoneal cavity were either investigated immediately after harvesting or after culturing periods of up to six days for enzymic activities of aminopeptidase, esterase, lactate dehydrogenase and beta-galactosidase. A fairly good correlation exists between biochemical determinations of aminopeptidase and esterase activity and the mean of histochemical data. Following a sharp increase in the number of cells after stimulation, aminopeptidase, esterase and lactate dehydrogenase activities per cell were found to be increased. Moreover, the cells taken three or five days after simulation synthesized large amounts of aminopeptidase and esterase as shown by culturing experiments. This capacity of the cells was subsequently lost in cells harvested seven days after stimulation but beta-galactosidase increased and lactae dehydrogenase was more readily released into culture supernatants. The increase in aminopeptidase and esterase was dependent on protein synthesis since it was abolished by cycloheximide. Thioglycollate broth medium provokes immigration of cells into the peritoneal cavity where cells apparently differentiate by increasing their aminopeptidase and esterase concentrations, and by raising their intracellular catabolism rates, which leads eventually to the decay of the cells. The different enzymic phenotypes and the large heterogeneity at any time point after stimulation presumably also reflect different functional properties during the inflammatory process.

Toxin-specific ultrastructural alterations of the mouse liver after burn injuries and the possibility of a specific antitoxic therapy.

Electron-microscopic studies in mice revealed similar and comparable mitochondrial alterations of the liver cells 5-7 days after either a sublethal controlled burn injury or an i.p. injection of an equivalent dose of a burn toxin. Electron microscopy 5 days after i.p. application of different amounts of the burn toxin in rats showed that the extent of the liver alterations correlates directly to the applied dose (occurrence of: cristolysis--intramitochondrial vacuolization--total vacuolar changes of mitochondria(. Controls with the non-toxic/"native" compound isolated from normal skin or excision of a skin piece identical in size to the sublethal burn showed no ultrastructural changes in the liver of mice or rats. In a 2nd series of experiments the therapeutic effect of an antitoxic IgG raised in sheep was tested. The first 3 days after a standard burn or an i.p. injection of 15 mg burn toxin mice obtained 10 mg of the antitoxic IgG (2x/day). Controls injected with the "native" compound or excised as described were treated in the same way. The results showed a specific complete immunological protection from mitochondrial alterations by either the toxin or the burn injury. These results suggest the possibility of an antitoxic IgG-therapy in severe burns.