lipid X

04/01/1988 - "Lipid X is a novel agent that enhances survival in an animal model of severe infection with gram-negative organisms."
07/01/1991 - "Furthermore, batch A was pyrogenic in rabbits at a dose of 0.05 mg/kg, whereas batch B was not pyrogenic at doses of up to greater than or equal to 2 mg/kg. However, both batches were equally tolerated by galactosamine-loaded mice at doses of up to 100 mg/kg. Surprisingly, while only batch A protected neutropenic mice against lethal infection with Pseudomonas aeruginosa (50% effective dose, 12.4 mg/kg), both batches were equally protective against infection with herpes simplex virus type 1 in mice and guinea pigs, even when lipid X was administered therapeutically. "
04/01/1988 - "To test the hypothesis that lipid X could be therapeutic against infections with gram-negative organisms, neutropenic ICR mice were infected by intramuscular inoculation of Escherichia coli and subsequently treated with lipid X alone or in combination with the antibiotic ticarcillin. "
01/01/1988 - "Lipid X (2,3-diacylglucosamine 1-phosphate) is a novel monosaccharide precursor of lipid A (the active moiety of gram-negative endotoxin) and has been found to be protective against endotoxin administered to mice and sheep and against life-threatening gram-negative infections in mice. "

01/01/1988 - "The pharmacokinetics described here should greatly aid in the design and interpretation of animal studies investigating the therapeutic applications of lipid X in gram-negative septicemia."
02/01/1993 - "These data do not support a therapeutic role for lipid X in the treatment of gram-negative sepsis."
01/01/1988 - "Because of the need to design optimal dosing regimens in experimental models of ovine and murine septicemia, the pharmacokinetic profile of lipid X was investigated in sheep and in two strains of mice by using 32P-labeled lipid X. In sheep, peak whole blood lipid X levels after a bolus injection of 100 micrograms of lipid X per kg were 900 ng/ml. An initial rapid distribution phase of 7.98 +/- 0.1 min was observed, followed by a prolonged elimination phase of 3.0 +/- 0.5 h; the area under the curve from time zero to infinity was 428 +/- 27 ng.h/ml. The serum half-lives of lipid X were slightly shorter than whole blood half-lives, suggesting that lipid X associates with cellular elements. "
09/01/1987 - "Lipid X appears to have a novel mechanism of inhibiting LPS effect and may have efficacy in the treatment of gram-negative sepsis."
10/01/1987 - "Lipid X is a potential prototype compound for a new type of chemotherapy directed at blocking the harmful effects of LPS during bacterial septicemia."

10/01/1987 - "A higher dose of lipid X, 200 micrograms/kg, produced pulmonary hypertension. "
10/01/1987 - "Lipid X ameliorates pulmonary hypertension and protects sheep from death due to endotoxin."
03/01/1987 - "Prior administration of indomethacin blocked the pulmonary pressor activity of lipid X, whereas prior administration of MAGP increased both the magnitude and the duration of the pulmonary pressure response of lipid X. We conclude that the initial pulmonary hypertension seen after lipid X injection may involve cyclooxygenase-dependent formation of prostaglandins and that the genesis of this pulmonary pressor activity is at least in part dependent on the ester-linked hydroxymyristoyl moiety at position 3 of the lipid X molecule.(ABSTRACT TRUNCATED AT 250 WORDS)"

06/01/1986 - "Dose-response studies revealed that lipid X induced the production of smaller amounts of the tumor-cytotoxic factor than LPS at low concentrations, but it induced that of considerable amounts at and over 1 microgram/ml. Elimination of 1-phosphate or 3-O-beta-hydroxymyristoyl group from lipid X completely prevented the induction of producing this factor by the macrophages. "
12/15/1987 - "Macrophage tumor cells also had the ability to inactivate lipid X by dephosphorylating it."
06/01/1986 - "Therefore, it is suggested that both 1-phosphate and 3-O-beta-hydroxymyristoyl groups are essential for the biologic activity of lipid X, as to the induction of the tumor-cytotoxic factor production in the macrophages."
11/18/1985 - "Lipid X is a diacylglucosamine 1-phosphate bearing beta-hydroxymyristoyl groups at positions 2 and 3. Lipid X, as well as lipopolysaccharide and lipid A, enhanced O2- generation in mouse peritoneal macrophages and a macrophage-like cell line, J774.1, and further induced the tumor-cytotoxic activity of peritoneal macrophages. "
12/15/1987 - "N2,O3-Diacylglucosamine 1-phosphate (lipid X), a monosaccharide precursor of Escherichia coli lipid A, was used to stimulate RAW 264.7 macrophage tumor cells, and the effects on macrophage phospholipid metabolism were examined. "

02/01/1993 - "Therapeutic trial of lipid X in a canine model of septic shock."
02/01/1993 - "Although lipid X has antiendotoxin effects, no benefit could be demonstrated in this antibiotic-treated, gram-negative bacillary-infected model of septic shock. "