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PubMed1998

Distribution of endotoxins in tissues and circulation and its effects following hemorrhagic shock.

OBJECTIVE: To systemically investigate 1) distribution of endogenous endotoxin (ET) in tissues and circulation; 2) its relationship with shock duration and organ damage; and 3) its possible mechanism after hemorrhagic shock. METHODS: To further elucidate the intrinsic relationship between endogenous endotoxin translocation and hemorrhagic shock, the present study systematically investigated the distribution of endogenous ET into the liver, lungs, kidneys and circulation, and the relationship between ET levels and the corresponding organ dysfunction with limulus amebocyte lysate (LAL) chromogenic assay following hemorrhagic shock in rats. RESULTS: It was found that ET levels in hepatic homogenate markedly increased (P = 0.09) 1.5 hours following shock compared with that in the sham group. After resuscitation, ET levels in hepatic, pulmonary and renal tissues were all significantly elevated. The levels kept increasing with the prolonged experimental time, and reached as high as 3.88 +/- 0.95 EU (endotoxin unit)/g in the livers, 2.53 +/- 1.46 EU/g in the lungs and 2.51 +/- 0.89 EU/g in the kidneys 12 hours after shock. ET levels in plasma reached a peak of 1.13 +/- 0.42 EU/ml at 1 hour following resuscitation, then rapidly decreased to the sham levels 3 hours following resuscitation. There was a close relationship between endotoxin translocation and shock duration. Correlation analysis further indicated that the changes in glutamic-pyruvic transaminase (GPT), blood urea nitrogen (BUN) in plasma and angiotensin I-converting exzyme (ACE) in pulmonary homogenate were significantly and positively correlated with the ET levels in the liver, kidneys and lungs after hemorrhagic shock. CONCLUSIONS: Hemorrhagic shock can induce obvious endogenous ET translocation, which is closely related to the shock duration. Although only transient endotoxemia occurs after hemorrhagic shock, ET can massively accumulate in tissues (liver, lungs and kidneys), and may play an important role in the development of shock.

Animals↗
PubMed1999

Importance of sampling, extraction and preservation for the quantitation of biologically active endoto.

The influence of filter media, extraction solution and preservation method on detection of biologically active endotoxin in the LAL assay was studied with air samples collected from wastewater treatment plants. The four most common types of filters were used as collection media. The extraction solutions compared were nonpyrogenic water, KH2PO4-triethylamine and Trizma buffers. The effect of preservation on endotoxin air samples was ascertained by storing both the filters without extraction, and samples extracted in the collection day for a few weeks at various temperatures. Samples collected on glass fibre filters showed the highest amounts of detectable endotoxin, while the concentrations of endotoxin were significantly lower when cellulose-mixed esters, polycarbonate or polyvinyl chloride membrane filters were used for air sampling. After collection, the best efficiency for glass fibre filters was attained by extraction with nonpyrogenic water within 8 hours after sampling and storage of the extracts at 4 degrees C until they were analysed. If the filters were stored without extraction, the reduction in endotoxin levels of the sample was about 30% after 1 week preservation and about 70% after 2 weeks. The study shows that the effect of the filter material and preservation practice was significant. These factors play critical roles in assessing exposure to bacterial endotoxins within wastewater aerosols.

Aerosols↗
PubMed1999

Dustiness of chopped straw as affected by lignosulfonate as a dust suppressant.

Many sources add to the concentration of bioaerosols in livestock buildings, and source control is the number one priority for keeping a low concentration. Straw is a common but dusty bedding material in livestock buildings and the present study is focused on the dustiness of chopped straw (barley) as affected by lignosulfonate (LS) as a dust suppressant. A LS-solution was aerosolized in a spray chamber fitted to an existing bedding chopper to allow the chopped straw to adsorb the LS-solution. The dustiness of straw treated with LS was compared to non-treated straw. As storage conditions may affect dustiness, the study included treated straw kept for 4 weeks in sealed plastic bags. Dustiness of the chopped straw was measured in terms of the potential of the straw to emit bioaerosols in a rotating drum. The LS-treated straw proved low in dustiness compared to the non-treated straw. The dustiness with respect to the mass of dust was reduced by at least a factor of 6, and for fungi and endotoxin the factors of reduction were 4 and 3, respectively. Dustiness of LS-treated straw kept in plastic bags was reduced by a factor of 2 for mass of dust and by a factor of 4 for endotoxin, but dustiness for fungi was increased by a factor of 3. It is concluded that lignosulfonate has potential as a dust suppressant for chopped straw.

Aerosols↗
PubMed1999

Endotoxin exposure among softwood lumber mill workers in the Canadian province of British Columbia.

An increased prevalence of respiratory problems among softwood lumber mill workers has been observed in a number of studies. These workers are potentially exposed to a variety of respiratory hazards including wood dust, abietic or other resin acids, monoterpenes, and fungi, as well as endotoxins. The objectives of this study were to determine if lumber mill workers were exposed to hazardous levels of airborne endotoxin and to identify the factors contributing to high exposures. Personal endotoxin samples (n = 216) were collected in four lumber mills in the Canadian province of British Columbia. The mean personal exposure concentration was 2.09 ng/m.(3) and 9% of the samples were above 5 ng/m.(3). Factors related to the personal endotoxin exposure were type of job, use of compressed air, the percentage of time spent in a booth or cab during a shift, and dust concentration. Log storage practices were also suspected of playing a role. The levels of exposure observed in this study were low compared to the levels reported for populations with respiratory problems attributed to endotoxins.

Air Microbiology↗
PubMed1999

[beta-D-glucan].

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Glucans↗
PubMed1975

Endotoxinemia in renal transplant recipients.

Endotoxinemia in renal transplant recipients. In immunosuppressed renal transplant recipients a high incidence of endotoxinemia was found during chest or urinary tract infections. Although the endotoxinemia was protracted, indicating inability to eradicate the infection, yet in general the effects were benign and adverse renal damage was not seen. The Limulus gelation test has a positive contribution to make in the diagnosis of illness in transplant recipients.

Acute Disease↗
PubMed1999

[Intrapulmonary expression of tumor necrosis factor alpha mRNA and its significance in rats with acute pancreatitis].

It is thought that tumor necrosis factor (TNF) plays an important role in pathogenesis of acute lung injury or ARDS. So we want to get insight into the relationship between intrapulmonary expression of TNF-alpha gene and lung injury during acute necrotizing pancreatitis (ANP). In our study, acute edematous pancreatitis (AEP) and ANP were induced in rats by caerulein and sodium taurocholate respectively. After acute pancreatitis was induced, serum TNF-alpha was assessed by ELISA assay while endotoxin was assessed by limulus lysate test. Intrapulmonary expression of TNF-alpha mRNA was detected by semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) technique. Moreover, content of pulmonary lesion was investigated and graded with microscope. It was found that TNF-alpha concentration in blood elevated markedly after acute pancreatitis was induced, especially in ANP group. Results of RT-PCR revealed that no TNF-alpha mRNA could be detected in lung tissue from those rats undergoing sham-operation, but marked expression appeared 1 hour after AEP or ANP was induced. Upregulation of expression of TNF-alpha gene in the early 3 hours was similar in the two groups with pancreatitis, and since then expression of TNF-alpha mRNA in ANP group was stronger than that in AEP group. Serum endotoxin increased significantly 6 hours after ANP was induced, with a higher level at 12 hour. However, there was no marked change of endotoxin level in AEP group and control group. It is noted that intrapulmonary expression of TNF-alpha gene in ANP group reached its peak as soon as serum endotoxin increased markedly. Lung damage in ANP group was more serious than that in AEP group significantly. Score of lung injury correlated well with TNF-alpha concentration in blood and expression of its gene in lung tissue in either AEP group or ANP group, as well as with serum endotoxin in ANP group. So overwhelm expression of some harmful cytokines like TNF-alpha in lung tissue may be the main cause of lung injury during acute necrotizing pancreatitis, and stimulation of endotoxiemia can at least partly explain the upregulation of expression of TNF-alpha gene.

Animals↗
PubMed2001

Mistletoe lectin-1 increases tumor necrosis factor-alpha release in lipopolysaccharide-stimulated whole blood via inhibition of interleukin-10 production.

We examined the immunomodulatory properties of the mistletoe preparation Lektinol (standardized for mistletoe lectin-1) and recombinant mistletoe lectin-1 (rML-1) in vitro by assessing alterations in the cytokine response of human whole blood. Lektinol or rML-1 alone did not induce any cytokine release in unstimulated whole blood. However, the lipopolysaccharide (LPS)-induced release of tumor necrosis factor (TNF)-alpha was increased, and the secretion of interleukin (IL)-10 was reduced by Lektinol at a mistletoe lectin-1 (ML-1) concentration of 0.5 to 5 ng/ml, whereas the LPS-induced secretion of IL-1 beta, IL-6, IL-12, and interferon-gamma was not affected. Lektinol did not alter the initial phase of TNF-alpha production but sustained TNF-alpha levels longer than in the LPS controls. Recombinant ML-1, but not the recombinant B-chain alone, also increased TNF-alpha release and decreased IL-10 release. We propose that the increase in TNF-alpha release is due to a specific inhibition of IL-10 release by Lektinol. This conclusion is based on the observation that blocking of endogenously formed IL-10 by a neutralizing antibody results in a similar increase of TNF-alpha in the late production phase after LPS stimulation. This hypothesis was also corroborated by the finding that when endogenously formed IL-10 was blocked, Lektinol could no longer increase TNF-alpha release. These results indicate that Lektinol modulates the cytokine response of human whole blood to LPS in a proinflammatory fashion, which can be attributed to ML-1.

Adjuvants, Immunologic↗
PubMed2001

Chemical structure and biological activity of a lipid A component from Helicobacter pylori strain 206.

The chemical structure of a lipid A, which was obtained as a minor component from lipopolysaccharide of Helicobacter pylori strain 206-1, was determined to be a glucosamine beta-(1 -6) disaccharide 1-(2-aminoethyl)phosphate acylated by (R)-3-hydroxyoctadecanoic acid, (R)-3- hydroxyhexadecanoic acid, and (R)-3-(octadecanoyloxy)octadecanoic acid at the 2-, 3- and 2'-positions, respectively. Compared with the other major lipid A from the same strain, which was previously reported [Suda Y, Ogawa T, Kashihara W et al. Chemical structure of lipid A from Helicobacter pylori strain 206-1 lipopolysaccharide. J Biochem 1997; 121: 1129--1133], the structure was very similar with one exception. An (R)-3-hydroxyhexadecanoic acid was present at the 3-position of the novel lipid A component. The structure is apparently identical to one of the proposals by Moran et al. [Moran AP, Lindner B, Walsh EJ. Structural characterization of the lipid A component of Helicobacter pylori rough- and smooth-form lipopolysaccharides. J Bacteriol 1997; 179: 6453--6463], who concluded the same structure as the so-called major lipid A from the H. pylori strain NCTC 11637 but without isolating a homogeneous component. The endotoxic properties and pro-inflammatory cytokine-inducing activities of this novel tetra-acyl type lipid A were lower than those of previously reported major tri-acyl type lipid A.

Animals↗
PubMed2001

Evaluation of exposure to airborne bacterial endotoxins and peptidoglycans in selected work environments.

The aim of this study was to assess workers' exposure to endotoxins and peptidoglycans, as well as associations between workers' reported symptoms and the detected bacterial exposures. From the filter samples, biologically-active endotoxins were analysed with the Limulus amebocyte lysate (LAL) assay. The total amount of endotoxins was analysed as 3-hydroxy (OH) fatty acids with a gas chromatography-mass spectrometry (GC-MS) assay, which was also used to assess peptidoglycans as muramic acid. Biologically-active endotoxins related better to the self-reported symptoms than total endotoxins. Specific 3-OH-14:0 fatty acid in the total endotoxin samples associated better with the symptoms than other 3-OH fatty acids. Half of the surveyed 77 workers reported respiratory symptoms, 27% eye symptoms, and 10% fever or shivering. The proportion of workers with respiratory symptoms was greater when the concentration of endotoxins was over 25 ng/m3. These endotoxin levels were occasionally found in the air of most studied occupational environments. The muramic acid concentrations of peptidoglycans were highest (medians over 100 ng/m3) in the garbage-handling plant and in the grain/vegetable storage houses. The LAL assay for endotoxins, as well as the GC-MS assay analysing muramic acid for peptidoglycans or specific 3-OH fatty acids for endotoxins, seem to be suitable methods for evaluating workers' exposure to airborne bacteria.

Adolescent↗
PubMed2001

Pathophysiological relevance of the CD14 receptor in surgical patients: biological activity of endotoxin is regulated by the CD14 receptor.

Endotoxins (lipopolysaccharides, LPSs) are potent bacterial poisons, and they are always present in the intestine in considerable numbers. Stress, such that as a resulting from multiple injuries, burns, hypovolemia, hypoxia, intestinal ischemia, and surgery can lead to a breakdown of the gut barrier, allowing endotoxins to enter the systemic circulation via translocation. However, estimating the biological activity of translocated circulating endotoxins and identification of the mechanisms regulating their biological activities remain complex problems. CD14 has been found to exist as a soluble protein in the serum and as a glycosylphosphatidylinositol (GPI)-anchored protein of myeloid lineage cells. It plays key roles in both LPS-induced activation and in LPS internalization by cells. In this article, we outline: (i) the biological activity of circulating endotoxin; and (ii) the role of membrane and/or soluble CD14 regulating the bioactivity of circulating endotoxin in a human model of postoperative endotoxemia.

Anti-Bacterial Agents↗
PubMed2000

[Effect and mechanism of garlic juice and hydrogen peroxide on the degradation of lipopolysaccharide].

OBJECTIVE: To elucidate the effect and mechanism of garlic juice and hydrogen peroxide on the degradation of lipopolysaccharide (LPS). METHODS: Hot phenol-water method, phenol-chloroform-petroleum ether procedure, limulus lysate test, lowry's ash spetrographical examination and gas-liquid chromatography etc. were used in this study. RESULTS: The sequence of degradation effect was 30% hydrogen peroxide (H), the most powerful, followed by garlic juice (G), 1:1 diluted G and 3% H, their effects were dose dependent and G group was time dependent. The mechanism of H on LPS degradation was fractionization of phosphoryl in position 1 from lipid A, while that of G was complex, it could bound LPS molecule and influenced its effect besides LPS hydrolysis. CONCLUSION: The study may imply that the degradation position and mechanism on LPS are different and remain to be elucidated.

Biodegradation, Environmental↗
PubMed2001

Investigation of infection risk and the value of urine endotoxin during extracorporeal shock wave lithotripsy.

OBJECTIVE: To clarify the infection risks and the value of endotoxin determination in urine during extracorporeal shock wave lithotripsy (ESWL). METHODS: According to the distribution and complications of upper urinary calculi, 164 patients were divided into five groups. Group A consisted of 48 patients with 1 to 4 renal calculi, which were or less than 2 cm in diameter. Group B was composed of 24 patients with renal calculus larger than 2 cm in diameter or one to multiple renal calculi. Group C was composed of 22 patients with 1 to 3 renal calculi accompanied by 1 to 2 ureteric calculi. Group D consisted of 51 patients with 1 to 3 ureteric calculi that were 0.5 to 1.2 cm in diameter, respectively. Group E included 19 patients with complicated renal calculus, such as casting and staghorn renal calculus. Urine and blood samples of these patients were obtained before and after ESWL, respectively. Their urine samples were proven sterile prior to treatment. All samples were cultured for bacteria and investigated for endotoxin concentration by the limulus lysate test. RESULTS: No significant difference in serum endotoxin was noted before and after ESWL. Blood bacterial cultures were all negative in all patients after ESWL, similar to those before ESWL. Significant increases in urine endotoxin after ESWL compared with that before ESWL in patients of Groups B, C and E were observed, respectively (P < 0.05). There was no significant difference in urine endotoxin after ESWL compared with that before ESWL in patients of Groups A and D. The positive incidences of urine bacterial culture were significantly increased (P < 0.05) in Groups B and C and very significantly increased (P < 0.01) in Group E compared with those in Groups A and D. CONCLUSIONS: Urinary infection risk following ESWL was lower in patients with one to several renal calculi, which were less than 2 cm in diameter and did not interfere obviously with the urine flow or in patients with 1 to 3 ureteric calculi that were 0.5 to 1.2 cm in diameter. The risk was higher in those with complicated calculi, such as casting, staghorn renal calculus, renal calculus larger than 2 cm in diameter or renal calculi accompanied by ureteric calculi. For patients with higher infection risk after ESWL, prophylactic antibiotics are necessary even if bacteriuria is not present before ESWL. Endotoxin determination in urine is a reliable, sensitive and simple method for the diagnosis of bacterial infection in patients undergoing ESWL.

Adolescent↗
PubMedDate not supplied

[Intestinal microflora and concomitant gastrointestinal diseases in patients with chronic hepatitis B and C].

In chronic viral hepatitis B and C the development of intestinal dysbacteriosis and high occurrence of concomitant diseases of the gastrointestinal tract were observed. In cases of increased dysbacteriosis degree and in the presence of concomitant diseases the blood plasma of patients exhibited higher activity in reaction with the of amebocytes lysate obtained from crabs of the genus Limulus. A suggestion was made that the endotoxin of Gram negative intestinal microflora could probably play some role in the development of pathological processes in chronic viral hepatitis B and C.

Gastrointestinal Diseases↗
PubMed1999

[Research on cause of distinction in antiendotoxic activation of radix isatidis from different cultivated populations].

OBJECTIVE: To research into the cause of distinction in antiendotoxic activation of Radix Isatidis from different cultivated populations. METHOD: 19 samples of Radix Isatidis were gathered. 12 portions of seeds were cultivated in the same field in Shanghai, and the selected and artificially bred autotetraploid seeds were planted in 5 different locations. All the samples were compared through antiendotoxic experiment. RESULTS: There are some marked distinction among the 19 samples from different populations. The distinction of the 12 samples cultivated in the same field didn't disappear. The activation of autotetraploid from 5 different locations didn't vary on the whole. CONCLUSION: Germplasm is the main factor to cause activation distinctions of Radix Isatidis, while environment is less important.

Drugs, Chinese Herbal↗
PubMed1979

In vitro activation of neutrophils by suspensions of Mycobacterium leprae.

Activation, defined as an increase in the proportion of cells that reduce nitroblue-tetrazolium in vitro, is present in neutrophils from patients with reactional lepromatous leprosy but not in neutrophils from patients with non-reactional lepromatous leprosy. Neutrophils from patients with all forms of leprosy are equally well activated by endotoxin in vitro. We have now shown that in vitro activation induced by Mycobacterium leprae suspensions is of comparable magnitude in neutrophils from patients with all forms of leprosy (including lepromatous and reactional lepromatous leprosy). There is no intrinsic neutrophil anergy in patients with lepromatous leprosy vis-à-vis M. leprae as pertains to activation. Spontaneous activation in reactional lepromatous leprosy is likely due to an indirect mechanism, probably of immunologic nature, and not simply to the presence of circulating Mycobacterium leprae in the blood.

Adolescent↗
PubMed2000

[Evaluation on antiendotoxic action and antiviral action in vitro of tetraploid Isatis indigotica].

OBJECTIVE: To evaluate the pharmacological effect of tetraploid Isatis indigotica Fort. METHODS: Comparing these actions of tetraploid I. indigotica with those of the diploid parent. RESULTS: These actions of tetraploid I. indigotica were obviously stronger than those of the diploid parent. The pharmacological effect of leaves was greater than that of roots with identical ploidy. CONCLUSION: Tetraploid I. indigotica is a new line of better quality, deserving to be exploited and utilized on a large scale.

Animals↗