Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Limulus Test”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,153 records · Page 64Linked to original sources
PubMed1988

Endotoxemia and cholestasis.

Endotoxemia has been incriminated as a major cause of morbidity and mortality in patients with obstructive jaundice. It has been postulated that absence of gastrointestinal bile salt flow in cholestasis enhances portal absorption of bacterial endotoxin from the intestine, thereby predisposing the host to endotoxemia and its complications. This study re-evaluates this pathologic mechanism, using new quantitative chromogenic and conventional qualitative limulus techniques for the detection of bacterial endotoxin. Female Sprague-Dawley rats underwent either ligation of bile duct or sham operation. Serum total bilirubin, serum bile acid and intestinal bile acid concentrations were determined seven, 14 and 21 days after operation. Chromogenic and conventional qualitative limulus lysate endotoxin determinations were simultaneously performed on post-operative days two, seven, 14 and 21. Serum total bilirubin and bile acid concentrations were elevated and intestinal bile acid levels depressed at days seven, 14 and 21 (p less than 0.05). Results of quantitative and qualitative limulus studies failed to demonstrated the coexisting development of portal or systemic endotoxemia in rats with the bile duct ligated after diminution of flow of gastrointestinal bile salt. These data refute the hypothesis that flow of gastrointestinal bile salt enhances portal absorption of intestinally derived endotoxin and suggest alternative mechanisms are involved in the pathogenesis of endotoxemia in obstructive jaundice.

Animals↗
PubMed1987

Effect of activated charcoal on endotoxin adsorption. Part I. An in vitro study.

An in vitro study by using cross-linked agarose coated activated charcoal (CAAC-II) as adsorbent was conducted. Endotoxin was quantitatively measured by chromogenic method of limulus lysate test. Results of the study demonstrated that endotoxin was fairly efficiently removed by CAAC-II. It may therefore be possible for effective adsorption of endotoxin in vivo studies and warrant further experimental study for CAAC-II hemoperfusion in clinical endotoxemia.

Adsorption↗
PubMed1987

Modulation of the biological activity of bacterial endotoxin by incorporation into liposomes.

In an attempt to define the mechanism by which endotoxin induces its biological activity, we studied the effect of the incorporation of lipopolysaccharide and lipid A into phospholipid vesicles (liposomes) on the stimulation of the macrophage cell-line RAW 264.7 and on the coagulation of Limulus amoebocyte lysate. The incorporation of Salmonella minnesota smooth-and rough (Re) lipopolysaccharide or primarily monophosphoryl lipid A into multilamellar and small unilamellar vesicles consisting of phosphatidylcholine, phosphatidylserine and cholesterol (molar ratio 4:1:4) reduced the interleukin 1 inducing potency of these substances about 1000-fold. When corrected for the actual uptake of radiolabeled free and liposome-incorporated lipopolysaccharide by the cells, this difference amounted to 100- to 1000-fold. In addition, liposome-associated Re-lipopolysaccharide was about 1000-fold less potent in stimulating the Fc-receptor mediated uptake of IgG-coated sheep erythrocytes by the cells. The ability of lipopolysaccharide and lipid A to coagulate the Limulus amoebocyte lysate appeared to be at least 100-fold decreased upon incorporation into phospholipid vesicles. Control experiments demonstrated that liposomes prepared without lipopolysaccharide did not reduce the studied activities of free lipopolysaccharide. In conclusion, the incorporation of lipopolysaccharide into the liposomal membrane probably prevents the interaction of the hydrophobic portion of the lipid A component of lipopolysaccharide with the plasma-membrane structures involved in the activation of macrophages and with the proteins of the Limulus amoebocyte lysate. This indicates that the direct interaction of the lipid A moiety of lipopolysaccharide with the macrophage plasma-membrane is required to optimally trigger the studied responses.

Animals↗
PubMed1987

The effects of purified recombinant murine interleukin-3 and/or purified natural murine CSF-1 in vivo on the proliferation of murine high- and low-proliferative potential colony-forming cells: demonstration of in vivo synergism.

Purified natural murine L cell (macrophage) colony-stimulating factor (nCSF-1) and purified recombinant murine interleukin-3 (rIL-3) were administered to normal or lactoferrin-pretreated mice 20 to 24 hours before sacrifice. rIL-3 and nCSF-1 administered separately increased the percentage of macrophage high-proliferative potential colony-forming cells (HPP-CFC) and low-proliferative potential colony-forming cells (LPP-CFC) in active cell cycle. Endotoxin was not detected in the samples of nCSF-1 or rIL-3 with the Limulus lysate test, and the in vitro and in vivo hematopoietic stimulatory effects of both molecules were abolished or markedly reduced by 30 minutes' treatment at 100 degrees C, which demonstrates that the effects noted in vivo were not due to endotoxin. Combinations of low concentrations of rIL-3 and nCSF-1, which by themselves were inactive, increased the percentage of HPP-CFC and LPP-CFC in active cell cycle in a synergistic fashion. No significant change in the number of HPP-CFC or LPP-CFC per femur or femoral nucleated cellularity was observed. Thus, rIL-3 and nCSF-1 can synergize to effect the proliferation of the same cell populations in vivo.

Animals↗
PubMed1986

[Detection of endotoxins in radiopharmaceutical preparations--II. Comparison of the sensitivity of methods using the rabbit and the Limulus amoebocyte lysate for the detection of endotoxins].

The rise of the rabbit internal temperature after i.v. injection of an endotoxin solution is proportional to concentration. Gelation of Limulus amoebocyte, when in presence of an endotoxin solution, is also related to concentration. We compared the sensitivity of these two methods. With our experimental procedure, the rabbit is sensitive to a 0.40 ng/mL solution and the Limulus amoebocyte lysate to a 0.14 ng/mL solution. The rabbit sensitivity increase is related to the per kilogramme injected volume, whereas sensitivity is not related to the volume to check in the case of the lysate.

Animals↗
PubMed1986

Acute inflammatory effects of intratracheally instilled Escherichia coli endotoxin and sonicated suspension of Haemophilus pleuropneumoniae in swine.

A single bolus of either Escherichia coli endotoxin, sonicated suspension of Haemophilus pleuropneumoniae, or pyrogen-free normal saline was intratracheally instilled in six week old specific-pathogen-free pigs. Pigs exposed to E. coli endotoxin developed fever, leukopenia followed by leukocytosis, and endotoxemia. Leukocytosis was the only clinical abnormality noted in pigs receiving the sonicated suspension of H. pleuropneumoniae. At one day postexposure, focal areas of atelectasis and consolidation were observed in the caudal lung lobes of animals receiving either E. coli endotoxin or the sonicated suspension of H. pleuropneumoniae. Lesions were characterized by a neutrophilic bronchitis and bronchiolitis with alveolitis in the surrounding tissue. Increased numbers of alveolar macrophages and evidence of phagocytosis were observed by light and electron microscopy. No clinical abnormalities or lesions were observed in animals receiving normal saline. Lesions typical of acute porcine Haemophilus pleuropneumonia were not produced by either E. coli endotoxin or sonicated suspension of H. pleuropneumoniae, indicating that multiple virulence factors are probably involved in lesion development.

Animals↗