115,785 research outputs found
Effect of Escherichia coli endotoxin on Archachatina marginata haemolymph coagulation system
The effect of _E. coli_ endotoxin on the heamolymph coagulation response of _Archachatina marginata_ was studied. Heamocyte Lysate(HL), Haemocyte Lysate Supernatant(HLS) and Haemocyte Lysate Debris (HLD) were exposed to _Escherichia coli_ endotoxin. Controls were prepared with endotoxin-free water(<0.025 EU/ml). The differential protein coagulation was estimated in each mixture. Fractions of the haemolymph exposed to endotoxin produced higher protein coagulates than endotoxin-free fractions when incubated at 37 °C for 1 h (p<0.05). The results showed significantly higher (p<0.05) concentrations of protein coagulated when HL/plasma mixture were used than when either fraction was used. At a ratio 1:1 of HL:Plasma, highest protein coagulation was recorded. This study revealed that maximum protein coagulation in response to endotoxin was elicited by a synergy between plasma and haemocyte lysate(HL). From this research haemolymph fractions of Archachatina marginata may provide an alternative test material for endotoxin in medical preparations in the future
Changes in endotoxin levels in T2DM subjects on anti-diabetic therapies
Introduction
Chronic low-grade inflammation is a significant factor in the development of obesity associated diabetes. This is supported by recent studies suggesting endotoxin, derived from gut flora, may be key to the development of inflammation by stimulating the secretion of an adverse cytokine profile from adipose tissue.
Aims
The study investigated the relationship between endotoxin and various metabolic parameters of diabetic patients to determine if anti-diabetic therapies exerted a significant effect on endotoxin levels and adipocytokine profiles.
Methods
Fasting blood samples were collected from consenting Saudi Arabian patients (BMI: 30.2 ± (SD)5.6 kg/m2, n = 413), consisting of non-diabetics (ND: n = 67) and T2DM subjects (n = 346). The diabetics were divided into 5 subgroups based on their 1 year treatment regimes: diet-controlled (n = 36), metformin (n = 141), rosiglitazone (RSG: n = 22), a combined fixed dose of metformin/rosiglitazone (met/RSG n = 100) and insulin (n = 47). Lipid profiles, fasting plasma glucose, insulin, adiponectin, resistin, TNF-α, leptin, C-reactive protein (CRP) and endotoxin concentrations were determined.
Results
Regression analyses revealed significant correlations between endotoxin levels and triglycerides (R2 = 0.42; p < 0.0001); total cholesterol (R2 = 0.10; p < 0.001), glucose (R2 = 0.076; p < 0.001) and insulin (R2 = 0.032; p < 0.001) in T2DM subjects. Endotoxin showed a strong inverse correlation with HDL-cholesterol (R2 = 0.055; p < 0.001). Further, endotoxin levels were elevated in all of the treated diabetic subgroups compared with ND, with the RSG treated diabetics showing significantly lower endotoxin levels than all of the other treatment groups (ND: 4.2 ± 1.7 EU/ml, RSG: 5.6 ± 2.2 EU/ml). Both the met/RSG and RSG treated groups had significantly higher adiponectin levels than all the other groups, with the RSG group expressing the highest levels overall.
Conclusion
We conclude that sub-clinical inflammation in T2DM may, in part, be mediated by circulating endotoxin. Furthermore, that whilst the endotoxin and adipocytokine profiles of diabetic patients treated with different therapies were comparable, the RSG group demonstrated significant differences in both adiponectin and endotoxin levels. We confirm an association between endotoxin and serum insulin and triglycerides and an inverse relationship with HDL. Lower endotoxin and higher adiponectin in the groups treated with RSG may be related and indicate another mechanism for the effect of RSG on insulin sensitivity
Testing the relationship between gut permeability, elevation of systemic lipopolysaccharides and chronic disease : A thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Massey University, Manawatu, New Zealand
The aim of my thesis was to test whether an increase in the permeability of the gut is
accompanied by an increase in the level of systemic lipopolysaccharides (LPS), also
referred to as endotoxin. These two parameters were firstly concurrently determined
in healthy women after the treatment with a single dose of aspirin which is thought to
temporarily increase the paracellular permeability of the intestine. Gut permeability
and the levels of systemic LPS in healthy women were then compared with those in
women with Crohn’s disease (CD) as the latter are thought to have chronically
elevated paracellular permeability of the gut. Both groups also ingested a high fat
drink which is reported to results in the elevation of systemic LPS. In addition, faecal
calprotectin, a biomarker of ongoing inflammation in the gut, and LPS-binding protein
(LBP), a proposed indirect biomarker for the exposure to LPS in the systemic
circulation, were determined both in healthy women and in those with CD.
Data indicated that both temporary and chronic increase in the paracellular
permeability of the small intestine can be reliably determined by the 3-h excretion of
lactulose. Further the combination of levels of faecal calprotectin and 3-h excretion of
lactulose and mannitol is the most sensitive tool to distinguish between healthy
subjects and those with CD. Hence, it is evident that the combination of those three
parameters can be used to assess gut health. In contrast, the current available methods
for the direct assessment of the systemic level of LPS/endotoxin i.e. the Limulus
Amebocyte Lysate (LAL) assay for the quantification of endotoxin or ELISAs for the
quantification of LPS, are not reliable as the former is interfered by constituents of
serum and the latter failed to detect LPS from sources other than those provided from
the manufacturer of the kit. Hence, studies suggesting that the consumption of high fat
meals lead to elevations of systemic endotoxin and those suggesting that levels of systemic endotoxin is associated with the onset of metabolic syndrome are
questionable. It is therefore advisable to repeat those studies when accurate methods
for the quantification of LPS/endotoxin in the systemic circulation are available
ENDOTOXAEMIA, PULMONARY COMPLICATIONS, AND THROMBOCYTOPENIA IN LIVER TRANSPLANTATION
Plasma endotoxin was measured in 64 patients undergoing primary liver replacement. Endotoxin concentrations increased during the anhepatic phase of the operations, and remained high for several days. Although the severity of endotoxaemia did not correlate with duration of the anhepatic phase, there was a correlation between endotoxaemia and the need for perioperative platelet transfusions, ventilator dependency postoperatively, and one-month case-fatality
Flow and filtration imaging of single use sterile membrane filters
Sterile filters incorporating endotoxin adsorption function emerged recently
to pretreat dialysate liquids fed to a hemodialysis filtration process. Their
application significantly enhances the survival rate during dialysis treatment
as they function as sterile filters as well as an endotoxin adsorber. Little is
known about the fluid flow distribution in such single use membrane modules. We
report a detailed analysis of the local 3D flow field distribution in such
membrane modules using magnetic resonance flow imaging. Next to pure water
filtration representing the application case of endotoxin adsorption from an
already pure liquid, we also used the module as a filtration device rejecting
for instance colloidal silica. Such experiments performed in-situ allow the
quantification of cake layer development and its concomitant redistribution of
the flow field. Particularly novel is the quantification of the time evolution
of local permeate flux distribution. These detailed insights of this study
encourage the use of flow-MRI when designing and applying new membrane module
configurations
Within-Home versus Between-Home Variability of House Dust Endotoxin in a Birth Cohort
Endotoxin exposure has been proposed as an environmental determinant of allergen responses in children. To better understand the implications of using a single measurement of house dust endotoxin to characterize exposure in the first year of life, we evaluated room-specific within-home and between-home variability in dust endotoxin obtained from 470 households in Boston, Massachusetts. Homes were sampled up to two times over 5–11 months. We analyzed 1,287 dust samples from the kitchen, family room, and baby’s bedroom for endotoxin. We fit a mixed-effects model to estimate mean levels and the variation of endotoxin between homes, between rooms, and between sampling times. Endotoxin ranged from 2 to 1,945 units per milligram of dust. Levels were highest during summer and lowest in the winter. Mean endotoxin levels varied significantly from room to room. Cross-sectionally, endotoxin was moderately correlated between family room and bedroom floor (r = 0.30), between family room and kitchen (r = 0.32), and between kitchen and bedroom (r = 0.42). Adjusting for season, the correlation of endotoxin levels within homes over time was 0.65 for both the bedroom and kitchen and 0.54 for the family room. The temporal within-home variance of endotoxin was lowest for bedroom floor samples and highest for kitchen samples. Between-home variance was lowest in the family room and highest for kitchen samples. Adjusting for season, within-home variation was less than between-home variation for all three rooms. These results suggest that room-to-room and home-to-home differences in endotoxin influence the total variability more than factors affecting endotoxin levels within a room over time
Role of P-selectin in platelet sequestration in pulmonary capillaries during endotoxemia
Background: There is growing evidence that platelets accumulate in the lung and contribute to the pathogenesis of acute lung injury during endotoxemia. The aims of the present study were to localize platelet sequestration in the pulmonary microcirculation and to investigate the role of P-selectin as a molecular mechanism of platelet endothelial cell interaction. Methods: We used in vivo fluorescence microscopy to quantify the kinetics of fluorescently labeled erythrocytes and platelets in alveolar capillary networks in rabbit lungs. Results: Six hours after onset of endotoxin infusion we observed a massive rolling along and firm adherence of platelets to lung capillary endothelial cells whereas under control conditions no platelet sequestration was detected. P-selectin was expressed on the surface of separated platelets which were incubated with endotoxin and in lung tissue. Pretreatment of platelets with fucoidin, a P-selectin antagonist, significantly attenuated the endotoxin-induced platelet rolling and adherence. In contrast, intravenous infusion of fucoidin in endotoxin-treated rabbits did not inhibit platelet sequestration in pulmonary capillaries. Conclusion: We conclude that platelets accumulate in alveolar capillaries following endotoxemia. P-selectin expressed on the surface of platelets seems to play an important role in mediating this platelet-endothelial cell interaction. Copyright (c) 2006 S. Karger AG, Basel
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Sex Differences in the Effect of Inflammation on Subjective Social Status: A Randomized Controlled Trial of Endotoxin in Healthy Young Adults.
It has been established that inflammation leads to a variety of changes in social experience, but one area of social experience that has been overlooked is subjective social status. Furthermore, given sex differences in the relationship between inflammation and social status, males may be more sensitive to inflammation-induced changes in social status. However, no previous studies in humans have examined this possibility. In the present study, healthy young participants (n = 115) were randomly assigned to receive either endotoxin, an experimental inflammatory challenge, or placebo. Participants reported their subjective social status at baseline (prior to injection), and approximately 2 h later (time of peak inflammatory response for the endotoxin group). Results, using ANCOVA analyses, indicated that males exposed to endotoxin, but not females, reported lower levels of subjective social status at the peak of inflammatory response (vs. placebo). These results suggest that males may be more sensitive to the effects of inflammation in certain social domains, such as perceived social status. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT01671150
Correlation of Lipopolysaccharide Endotoxin Level in Cotton Dust with the Increase of TNFα Level and the Decline of Lung Function in Cotton Spinning Factory Workers
Lipopolysaccharide (LPS) endotoxin contained in cotton dust may cause airway inflammation and decline of lung function when inhaled, which eventually leads to respiratory symptoms. The objective of this research is to analyze the correlation of the exposure of LPS endotoxin in cotton dust with the increase of TNFα level and the decline of lung function after one day’s work. This study applies analytical observation method and prospective cohort approach. Main participants of this study were the workers of a cotton spinning factory located in Tulangan District, Sidoarjo Regency, East Java Province. Sixteen samples from cotton factory were taken as study group, and twenty three samples from village administrators were taken as control group. Data collection involves several techniques: spirometry, laboratory test, and interview. Results showed that concentration of personal dust has a significant relationship with the decline of FVC, %FVC, FEV1, and %FEV1, with Pearson correlation test showing p<0.05. LPS endotoxin in personal dust samples has a significant relationship with the increase of blood serum TNFα and the decline of FEV1 and %FEV1, with Pearson correlation test showing p>0.05. The research concludes that the level of LPS endotoxin was strongly related to the increase of blood serum TNFα and the decline of lung function. Development of more effective preventive measures such as stronger enforcement of worker’s health maintenance regulations and use of personal protective equipment is needed to ensure the best protection of cotton workers’ health
Integrated dataset on acute phase protein response in chicken challenged with Escherichia coli lipopolysaccharide endotoxin
Data herein describe the quantitative changes in the plasma proteome in chickens challenged with lipopolysaccharide (LPS), a bacterial endotoxin known to stimulate the host innate immune system obtained by shotgun quantitative proteomic tandem mass tags approach using high-resolution Orbitrap technology. Statistical and bioinformatic analyses were performed to specify the effect of bacterial endotoxin. Plasma from chicken (N=6) challenged with Escherichia coli (LPS) (2 mg/kg body weight) was collected pre (0 h) and at 12, 24, 48, and 72 h post injection along with plasma from a control group (N=6) challenged with sterile saline. Protein identification and relative quantification were performed using Proteome Discoverer, and data were analysed using R. Gene Ontology terms were analysed by the Cytoscape application ClueGO based on Gallus gallus GO Biological Process database, and refined by REVIGO. Absolute quantification of several acute phase proteins, e.g. alpha-1-acid glycoprotein (AGP), serum amyloid A (SAA) and ovotrensferrin (OVT) was performed by immunoassays to validate the LC-MS results. The data contained within this article are directly related to our research article”Quantitative proteomics using tandem mass tags in relation to the acute phase protein response in chicken challenged with Escherichia coli lipopolysaccharide endotoxin” [1]. The raw mass spectrometric data generated in this study were deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier PXD009399 (http://proteomecentral.proteomexchange.org/cgi/GetDataset?ID=PXD009399)
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