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Sample records for bacterial endotoxins test

  1. Biochemical principle of Limulus test for detecting bacterial endotoxins

    OpenAIRE

    Iwanaga, Sadaaki

    2007-01-01

    A hemocyte lysate from horseshoe crab (Limulus) produced a gel, when exposed to Gram-negative bacterial endotoxins, lipopolysaccharides (LPS). This gelation reaction of the lysate, so-called Limulus test, has been widely employed as a simple and very sensitive assay method for endotoxins. Recent biochemical studies on the principle of Limulus test indicate that the hemocytes contain several serine protease zymogens, which constitute a coagulation cascade triggered by endotoxins, and that ther...

  2. [Application of a bacterial endotoxin test for parenteral drugs].

    Science.gov (United States)

    Ogawa, Y

    1994-01-01

    The Limulus test, which has been adopted as the Test for Bacterial Endotoxins in the JP XII, can detect or quantitate endotoxins of Gram-negative bacterial origin using blood corpuscle extracts (Limulus amebocyte lysate, LAL) of horseshoe crabs (Limulus polyphemus, Tachypleus tridentatus, etc.). It may be conducted by the gel-clot or spectrophotometric (turbidimetric and colorimetric) techniques, the former being based on gel formation due to the activation of LAL by endotoxins. The turbidimetric technique is based on the LAL turbidity change during the gel formation and the colorimetric technique on activation of peptide hydrolytic enzymes in LAL. The Limulus test has been unofficially utilized as a simple and highly sensitive method for the determination of endotoxins in parenteral drugs in lieu of the in vivo Pyrogen Test using rabbits. For the Bacterial Endotoxins Test of the JP XII, the gel-clot technique alone was adopted, the technique being only allowed for Injection. Although most parenteral drugs show inhibition or enhancement in practice, this test can be most easily conducted by eliminating interfering effects through dilution of specimens by a factor not exceeding the maximum valid dilution (MVD) with water. Since MVD is dependent on the sensitivity of applied methodology, the turbidimetric and colorimetric techniques, which are more sensitive than the gel-clot technique, have a distinct advantage. The JP, as the leading Pharmacopoeia for the international harmonization of Bacterial Endotoxins Testing, has presented a "Draft towards International Harmonization of Bacterial Endotoxins Test", whose main purpose is the introduction of supplementary turbidimetric and colorimetric techniques. Under these circumstances the following subjects are discussed: (1) the proposal that, with a view towards international harmonization of the technical requirements of Pharmacopoeias, both the turbidimetric and colorimetic techniques should be included together with

  3. Biochemical principle of Limulus test for detecting bacterial endotoxins.

    Science.gov (United States)

    Iwanaga, Sadaaki

    2007-05-01

    A hemocyte lysate from horseshoe crab (Limulus) produced a gel, when exposed to Gram-negative bacterial endotoxins, lipopolysaccharides (LPS). This gelation reaction of the lysate, so-called Limulus test, has been widely employed as a simple and very sensitive assay method for endotoxins. Recent biochemical studies on the principle of Limulus test indicate that the hemocytes contain several serine protease zymogens, which constitute a coagulation cascade triggered by endotoxins, and that there is a (1,3)-β-D-glucan-mediated coagulation pathway which also results in the formation of gel. Up to now, six protein components, designated coagulogen, proclotting enzyme, factor B, factor C, and factor G, all of which are closely associated with the endotoxin-mediated coagulation pathway, have been purified and biochemically characterized. The molecular structures of these proteins have also been elucidated. Moreover, the reconstitution experiments using the isolated clotting factors, factor C, factor B, proclotting enzyme and coagulogen in the presence of endotoxin, leads to the formation of coagulin gel. Here, I will focus on the biochemical principle of Limulus test for detecting bacterial endotoxins, and its activation and regulation mechanism on the LPS-mediated coagulation cascade.

  4. Short time bacterial endotoxins test for positron emission tomography by means of positively charged filters

    Energy Technology Data Exchange (ETDEWEB)

    Nakazawa, Nobuhiro; Wakita, Kazuo [Nishijin Hospital, Kyoto (Japan); Mineura, Katsuyoshi [Kyoto Prefectural Univ. of Medicine (Japan)] (and others)

    2002-11-01

    Positron emission tomography (PET) radiotracers have very short physical half-lives. It is hard to complete a bacterial endotoxins test prior to release from medical institutes. For endotoxin quantitative determination, limulus amebocyte lysate (LAL) reagent and kinetic-turbidimetry system were previously developed. We investigated the possibility of a short time test by means of positively charged filters. As a result of this study, the effects of positively charged filters on endotoxin removal were over 99.5% for [{sup 18}F]FDG and [{sup 18}F]NaF, which were contaminated with the indicated concentration of endotoxin. Combining this filter and the kinetic-turbidimetric method, it was possible to complete a bacterial endotoxins test in 5 min prior to the patient's administration. This test should be required prior to release for PET radiopharmaceutical quality control. It has been suggested that this combination is a good method for this purpose. (author)

  5. Tachypleus lysate test for endotoxin in patients with Gram negative bacterial infections.

    Science.gov (United States)

    Usawattanakul, W; Tharavanij, S; Limsuwan, A

    1979-03-01

    Amoebocyte lysate from the horseshoe crabs (Tachypleus gigas) which abounds in the Gulf of Thailand was used to detect endotoxin in patients with Gram-negative bacteremia, in patients with Gram-positive bacterial infections as well as in the control. The Tachypleus lysate test (TLT) was positive in 94.4% of 36 patients with Gram-negative bacteremia before initiation of antibiotic therapy. Only 4% of 50 healthy individuals were positive and all 7 patients with Gram-positive bacterial infections were negative. The threshold sensitivity of TLT was 0.625 micrograms endotoxin per ml of the plasma. In comparison with the commercial Limulus lysate test (LLT), the TLT was slightly more sensitive in exhibiting higher grade of reaction, eventhough the threshold sensitivity was the same.

  6. Quality-control analytical methods: endotoxins: essential testing for pyrogens in the compounding laboratory, part 3: a simplified endotoxin test method for compounded sterile preparations.

    Science.gov (United States)

    Cooper, James F

    2011-01-01

    The first two parts of the IJPC series on endotoxin testing explained the nature of pyrogenic contamination and described various Limulus amebocyte lysate methods for detecting and measuring endotoxin levels with the bacterial endotoxin test described in the United States Pharmacopeia. This third article in that series describes the endotoxin test that is simplest to permorm for pharmacists who prefer to conduct an endotoxin assa at the time of compounding in the pharmacy setting.

  7. Bacterial endotoxin adhesion to different types of orthodontic adhesives

    Directory of Open Access Journals (Sweden)

    Priscilla Coutinho ROMUALDO

    Full Text Available Abstract Bacterial endotoxin (LPS adhesion to orthodontic brackets is a known contributing factor to inflammation of the adjacent gingival tissues. Objective The aim of this study was to assess whether LPS adheres to orthodontic adhesive systems, comparing two commercial brands. Material and Methods Forty specimens were fabricated from Transbond XT and Light Bond composite and bonding agent components (n=10/component, then contaminated by immersion in a bacterial endotoxin solution. Contaminated and non-contaminated acrylic resin samples were used as positive and negative control groups, respectively. LPS quantification was performed by the Limulus Amebocyte Lysate QCL-1000™ test. Data obtained were scored and subjected to the Chi-square test using a significance level of 5%. Results There was endotoxin adhesion to all materials (p0.05. There was no significant difference (p>0.05 among commercial brands. Affinity of endotoxin was significantly greater for the bonding agents (p=0.0025. Conclusions LPS adhered to both orthodontic adhesive systems. Regardless of the brand, the endotoxin had higher affinity for the bonding agents than for the composites. There is no previous study assessing the affinity of LPS for orthodontic adhesive systems. This study revealed that LPS adheres to orthodontic adhesive systems. Therefore, additional care is recommended to orthodontic applications of these materials.

  8. Endotoxin, thrombin, and the Limulus amebocyte lysate test.

    Science.gov (United States)

    Yin, E T

    1975-09-01

    The Limulus amebocyte lysate, a proteinaceous composite isolated from the hemolymph cells of the horseshoe crab (Limulus polyphemus) is sensitive to picogram quantities of Gram-negative bacterial lipopolysaccharides. However, a controversy currently exists as to whether the Limulus amebocyte lysate is specifically sensitive to Gram-negative bacterial endotoxins as a result of a recent report that the blood coagulation protease, thrombin, can mimic endotoxins in the Limulus amebocyte lysate test. Experiments including those employing two highly purified fractions isolated from the Limulus lystae have provided us with evidence that thrombin per se is unable to mimic endotoxin.

  9. THE EFFECTS OF BACTERIAL ENDOTOXIN ON LIPIDE METABOLISM

    Science.gov (United States)

    LeQuire, V. S.; Hutcherson, J. D.; Hamilton, R. L.; Gray, M. E.

    1959-01-01

    Single intravenous injections of Shear's polysaccharide in varying dosages invariably produced an elevation in the levels of the total serum lipides 24 hours after injection of endotoxin. The total serum cholesterol and lipide phosphorus were also affected, although they did not change with smaller doses of endotoxin and were rarely elevated to the same degree as were the total serum lipides. The degree of elevation of the serum lipides was apparently related to the amount of endotoxin injected up to a certain point, beyond which there was no further increase. There were two types of response to endotoxin by the serum lipides, a moderate increase and an uncontrolled increase. Higher dosages of endotoxin and fasting apparently increased the incidence of the latter response. No direct correlation could be made between serum lipide responses and histologic evidence typical of the generalized Shwartzman reaction following this regimen of endotoxin injection. The Shwartzman reaction did occur with greater frequency and with lower dosages of endotoxin in fasted animals. Animals given repeated injections of endotoxin showed an initial increase in serum lipides followed by a progressive decrease to normal levels as tolerance to the febrile action of endotoxin appeared. The febrile tolerance as well as the unresponsiveness of the serum lipides to endotoxin was abolished by thorium dioxide (thorotrast) in these animals. In similar experiments a "breakthrough" of lipide unresponsiveness to endotoxin was obtained by increasing the amount of endotoxin injected. Some of the implications of these results for the metabolic alterations produced by bacterial endotoxins are discussed. PMID:13673140

  10. Effect of the dilution factor on 18FDG and Na18F samples for bacterial endotoxin test using PTS (portable test system)

    International Nuclear Information System (INIS)

    Silveira, Marina B.; Costa, Flavia M.; Ferreira, Soraya Z.

    2011-01-01

    18 FDG and Na 18 F are radiopharmaceuticals produced as sterile solutions suitable for intravenous administration, which must contain no more than 175 EV/V. The most commonly used approach to detect endotoxins is the gelclot technique that requires 60 minutes for results. For radiopharmaceuticals containing short-life radionuclides, such as 18 F, there is an increasing interest for faster quality control methods. FDA licensed the Endosafe, PTS, a kinetic chromogenic endotoxin detection system that takes about 15 minutes for results. As other techniques, PTS test is susceptible to interferences which can be solved by product dilution. The aim of this study was to establish the best dilution of 18 FDG and Na 18 F for PTS analysis. Two different dilution factors for 18 FDG and 1:10 for Na 18 F were essayed: 1:10 and 1:100. 18 FDG and Na 18 solutions were prepared by the addition of LAL reagent water. Considering the assay acceptance criteria, the best dilution factor was 1:100 for 18 FDG and 1:10 for Na 18 F. The recovery of the product positive control was 98-12% for 18 FDG 1:100 and 104-120% for Na 18 F 1:10, which were, in both cases, within the specification (50-200%) and very close to 100%. Results obtained with these dilution studies were important to establish the most appropriate and non-interfering dilution factor for 18 FDG and Na 18 F routine endotoxin test. (author)

  11. DMPD: Targeting bacterial endotoxin: two sides of a coin. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17405910 Targeting bacterial endotoxin: two sides of a coin. Bosshart H, Heinzelman...n M. Ann N Y Acad Sci. 2007 Jan;1096:1-17. (.png) (.svg) (.html) (.csml) Show Targeting bacterial endotoxin: two sides of a coin.... PubmedID 17405910 Title Targeting bacterial endotoxin: two sides of a coin. Authors Bo

  12. A selective sorbent for removing bacterial endotoxins from blood

    Science.gov (United States)

    Morozov, A. S.; Kopitsyna, M. N.; Bessonov, I. V.; Karelina, N. V.; Nuzhdina, A. V.; Sarkisov, I. Yu.; Pavlova, L. A.; Tsyurupa, M. P.; Blinnikova, Z. K.; Davankov, V. A.

    2016-12-01

    Synthetic ligands carrying a positive charge and capable of selective binding of bacterial endotoxins are covalently immobilized on surfaces of domestic hemosorbent Styrosorb-514 based on hypercrosslinked polystyrene. It is shown that the resulting sorbent aimed at treating sepsis exceeds imported specific hemosorbent in Toraymyxin™ columns in removing lipopolysaccharides, and can be used in domestically-produced Desepta columns.

  13. Determination of bacterial endotoxin (pyrogen) in radiopharmaceuticals by the gel clot method. Validation

    International Nuclear Information System (INIS)

    Fukumori, Neuza Taeko Okasaki

    2008-01-01

    Before the Limulus amebocyte lysate (LAL) test, the only available means of pirogenicity testing for parenteral drugs and medical devices was the United States Pharmacopoeia (USP) rabbit pyrogen test. Especially for radiopharmaceuticals, the LAL assay is the elective way to determine bacterial endotoxin. The aim of this work was to validate the gel clot method for some radiopharmaceuticals without measurable interference. The FDA's LALTest guideline defines interference as a condition that causes a significant difference between the endpoints of a positive water control and positive product control series using a standard endotoxin. Experiments were performed in accordance to the USP bacterial endotoxins test in the 131 I- m-iodobenzylguanidine; the radioisotopes Gallium-67 and Thallium-201; the lyophilized reagents DTPA, Phytate, GHA, HSA and Colloidal Tin. The Maximum Valid Dilution (MVD) was calculated for each product based upon the clinical dose of the material and a twofold serial dilution below the MVD was performed in duplicate to detect interferences. The labeled sensitivity of the used LAL reagent was 0.125 EU mL -1 (Endotoxin Units per milliliter). For validation, a dilution series was performed, a twofold dilution of control standard endotoxin (CSE) from 0.5 to 0.03 EU mL -1 , to confirm the labeled sensitivity of the LAL reagent being tested in sterile and non pyrogenic water, in quadruplicate. The same dilution series was performed with the CSE and the product in the 1:100 dilution factor, in three consecutive batches of each radiopharmaceutical. The products 131 I-m-iodobenzylguanidine, Gallium-67, Thallium-201, DTPA, HSA and Colloidal Tin were found compatible with the LAL test at a 1:100 dilution factor. Phytate and GHA showed some interference in the gel clot test. Other techniques to determine endotoxins as the chromogenic (color development) and the turbidimetric test (turbidity development), were also assessed to get valuable quantitative and

  14. Investigations on the specificity of the Limulus test for the detection of endotoxin.

    Science.gov (United States)

    Wildfeuer, A; Heymer, B; Schleifer, K H; Haferkamp, O

    1974-11-01

    Lysates obtained from amoebocytes of Limulus polyphemus, the horseshoe crab, showed gel formation after the addition of bacterial endotoxin. In contrast to living gram-negative bacteria, viable gram-positive microorganisms did not cause gelation of lysate. Nevertheless, peptidoglycan isolated from the cell walls of various gram-positive organisms did induce the reaction. However, the activity of peptidoglycan was 1,000 to 400,000 times less than that of Escherichia coli lipopolysaccharide. After exposure to lysozyme, peptidoglycan no longer gelled amoebocyte lysate, therefore apparently excluding endotoxin contamination. Gelation of amoebocyte lysate by endotoxin or peptidoglycan was inhibited by different concentrations of sodium polystyrolsulfonate. Whereas these studies confirm the specificity of the Limulus test for bacterial endotoxins, they also indicate that other substances of bacterial origin should be investigated for their ability to gel amoebocyte lysate.

  15. Application of Recombinant Factor C Reagent for the Detection of Bacterial Endotoxins in Pharmaceutical Products.

    Science.gov (United States)

    Bolden, Jay; Smith, Kelly

    2017-01-01

    Recombinant Factor C (rFC) is non-animal-derived reagent used to detect bacterial endotoxins in pharmaceutical products. Despite the fact that the reagent was first commercially available nearly 15 years ago, the broad use of rFC in pharmaceutical industry has long been lagging, presumably due to historical single-source supplier concerns and the lack of inclusion in worldwide pharmacopeias. Commercial rFC reagents are now available from multiple manufacturers, thus single sourcing is no longer an issue. We report here the successful validation of several pharmaceutical products by an end-point florescence-based endotoxin method using the rFC reagent. The method is equivalent or superior to the compendia bacterial endotoxins test method. Based on the comparability data and extenuating circumstances, the incorporation of the end point fluorescence technique and rFC reagent in global compendia bacterial endotoxins test chapters is desired and warranted. LAY ABSTRACT: Public health has been protected for over 30 years with the use of a purified blood product of the horseshoe crab, limulus amebocyte lysate. More recently, this blood product can be produced in biotech manufacturing processes, which reduces potential impacts to the horseshoe crab and related species dependent upon the crab, for example, migrating shorebirds. The pharmaceutical industry has been slow to adopt the use of this reagent, Recombinant Factor C (rFC), for various reasons. We evaluated the use of rFC across many pharmaceutical products, and in other feasibility demonstration experiments, and found rFC to be a suitable alternative to the animal-derived limulus amebocyte lysate. Incorporation of rFC and its analytical method into national testing standards would provide an equivalent or better test while continuing to maintain patient safety for those who depend on medicines and while securing pharmaceutical supply chains. In addition, widespread use of this method would benefit existing animal

  16. Tolerance of monocytes and macrophages in response to bacterial endotoxin

    Directory of Open Access Journals (Sweden)

    Ewelina Wiśnik

    2017-03-01

    Full Text Available Monocytes belong to myeloid effector cells, which constitute the first line of defense against pathogens, also called the nonspecific immune system and play an important role in the maintenance of tissue homeostasis. In response to stimulation, monocytes differentiate into macrophages capable of microorganism phagocytosis and secrete factors that play a key role in the regulation of immune responses. However excessive exposure of monocytes/macrophages to the lipopolysaccharide (LPS of Gram negative bacteria leads to the acquisition of immune tolerance by these cells. Such state results from disruption of different biological processes, for example intracellular signaling pathways and is accompanied by a number of disease states (immune, inflammatory or neoplastic conditions. Regulation of monocytes/macrophages activity is controlled by miRNAs, which are involved in the modulation of immune tolerance acquired by these cells. Moreover, the tolerance to endotoxin is conditioned by the posttranscriptional processes and posttranslational epigenetic modifications leading to the impairment of normal immune response for example by alterations in the expression of many genes encoding immune signaling mediators. The aim of this paper is to provide an overview existing knowledge on the modulation of activity of monocytes/macrophages in response to bacterial endotoxin and impaired immune responses.

  17. Detection of Endotoxin Contamination of Graphene Based Materials Using the TNF-α Expression Test and Guidelines for Endotoxin-Free Graphene Oxide Production.

    Directory of Open Access Journals (Sweden)

    Sourav P Mukherjee

    Full Text Available Nanomaterials may be contaminated with bacterial endotoxin during production and handling, which may confound toxicological testing of these materials, not least when assessing for immunotoxicity. In the present study, we evaluated the conventional Limulus amebocyte lysate (LAL assay for endotoxin detection in graphene based material (GBM samples, including graphene oxide (GO and few-layered graphene (FLG. Our results showed that some GO samples interfered with various formats of the LAL assay. To overcome this problem, we developed a TNF-α expression test (TET using primary human monocyte-derived macrophages incubated in the presence or absence of the endotoxin inhibitor, polymyxin B sulfate, and found that this assay, performed with non-cytotoxic doses of the GBM samples, enabled unequivocal detection of endotoxin with a sensitivity that is comparable to the LAL assay. FLG also triggered TNF-α production in the presence of the LPS inhibitor, pointing to an intrinsic pro-inflammatory effect. Finally, we present guidelines for the preparation of endotoxin-free GO, validated by using the TET.

  18. Chromogenic substrates for horseshoe crab clotting enzyme. Its application for the assay of bacterial endotoxins.

    Science.gov (United States)

    Iwanaga, S; Morita, T; Harada, T; Nakamura, S; Niwa, M; Takada, K; Kimura, T; Sakakibara, S

    1978-01-01

    An endotoxin-activated hemocyte lysate from the horseshoe crab (Tachypleus and Limulus) was found to hydrolyze Bz-Ile-Glu-(gamma-OR)-Gly-Arg-p-nitroanilide (PNA), Bz-Val-Gly-Arg-PNA, Boc-Val-Leu-Gly-Arg-PNA, and Boc-Leu-Gly-Arg-PNA, all of which have the COOH-terminal Gly-Arg sequence. This amidase activity was due to a clottting enzyme contained in the lysate. Furthermore, the amidase activity increased by increasing the concentration of bacterial endotoxin (E. coli, 0111-B4) added to the lysate. Therefore, the measurement of the endotoxin-induced amidase activity made it possible to determine the concentration of the endotoxin.

  19. Septic Participation in Cardiogenic Shock: Exposure to Bacterial Endotoxin.

    Science.gov (United States)

    Ramirez, Paula; Villarreal, Esther; Gordon, Monica; Gómez, María Dolores; de Hevia, Luis; Vacacela, Karla; Gisbert, Teresa; Quinzá, Adrian; Ruiz, Jesús; Alonso, Ricardo; Bonastre, Juan; Vila, Jordi

    2017-05-01

    In cardiogenic shock (CS), presence of fever, leukocytosis, relatively low systemic vascular resistances, and high serum procalcitonin levels are quite frequent and recurrently involve the search for an infectious complication. We hypothesized that endotoxin exposure in CS could explain this sepsis-like syndrome. Prospective observational study of consecutive CS patients admitted to our intensive care unit (ICU). Patients were followed during the first 3 days after CS onset. All clinical, hemodynamic, and microbiological data were collected. Inflammatory biomarkers and anti-endotoxin antibodies (IgM EndoCAb) were daily measured. We included 37 consecutive CS patients. Twenty-two patients (60%) had body temperature >38.3°C or 14,000/mm or <4,000/mm. Microbiological study was performed in 30 patients (81%). No infection was diagnosed in the studied patients. All the patients had serum inflammatory biomarkers levels above normal values including procalcitonin (19 patients [51%] had serum procalcitonin above 2 ng/mL). All the patients had IgM EndoCAb below the normal median value; 22 patients (59.5%) had IgM anti-endotoxin value below 10th percentile range for healthy people. Hemodynamic and respiratory stabilization was achieved in 23 patients (62%) and the ICU mortality rate was 38%, only procalcitonin and interleuquin-6 were associated with higher mortality rate. We have detected extremely low titers of IgM EndoCAb in CS suggesting endotoxin exposure. However, only inflammatory biomarkers were related to ICU mortality.

  20. Capacitive biosensor for detection of endotoxin.

    Science.gov (United States)

    Limbut, Warakorn; Hedström, Martin; Thavarungkul, Panote; Kanatharana, Proespichaya; Mattiasson, Bo

    2007-09-01

    A capacitive biosensor for the detection of bacterial endotoxin has been developed. Endotoxin-neutralizing protein derived from American horseshoe crab was immobilized to a self-assembled thiol layer on a biosensor transducer (Au). Upon injection of a sample containing endotoxin, a decrease in the observed capacitive signal was registered. Endotoxin could be determined under optimum conditions with a detection limit of 1.0 x 10(-13) M and linearity ranging from 1.0 x 10(-13) to 1.0 x 10(-10) M. Good agreement was achieved when applying endotoxin preparations purified from an Escherichia coli cultivation to the capacitive biosensor system, utilizing the conventional method for quantitative endotoxin determination, the Limulus amebocyte lysate test as a reference. The capacitive biosensor method was statistically tested with the Wilcoxon signed rank test, which proved the system is acceptable for the quantitative analysis of bacterial endotoxin (P<0.05).

  1. Limulus amebocyte lysate technique (LAL) for bacterial endotoxin control in radiodiagnosis agents (kits) and radioisotopes

    International Nuclear Information System (INIS)

    Morote, M.; Robles, A.; Ramos, B.; Otero, M.

    1997-01-01

    A procedure based on a fast technique of LAL individual kits has been devised to control bacterial endotoxins in radiodiagnosis agents (RDA): HEMTEC, DEIDA, PPI, AMD, GHCa, RENTEC, DMSA, MAA, TSC, HERTEC, DTPA, BRATEC and EDTMP as well as in radioisotopes I-131 and Tc99m. The procedures begins with the determination of the following values, injection volume (IV), endotoxin limits (EL), maximum valid dilution (MVD), total mass (TM), reconstitution volume (RV), concentration (mg/ml), and final dilution (FD). Subsequently, a procedure is carried out to conduct an 'in vitro' control of the radiodiagnosis agents and radioisotopes with LAL individual kits; the procedures includes: reconstitution of the sample to be controlled, dilution, inoculation of the diluted sample in LAL tubes and incubation at 37 o C for an hour. Finally, results are interpreted through the observation of gel formation or not in LAL tubes

  2. Endotoxin testing of proteins for parenteral administration using the Mono Mac 6 assay

    DEFF Research Database (Denmark)

    Moesby, Lise; Hansen, E W; Christensen, J D

    2000-01-01

    Pharmaceutical products containing proteins cause problems in testing for endotoxin and pyrogens. Many proteins interfere with the LAL test and the proteins are immunogenic in rabbits. The monocytic cell line Mono Mac 6 is an alternative assay for detection of endotoxin and other pyrogens....

  3. The effects of bacterial endotoxin on lipide metabolism. I. The responses of the serum lipides of rabbits to single and repeated injections of Shear's polysaccharide.

    Science.gov (United States)

    LEQUIRE, V S; HUTCHERSON, J D; HAMILTON, R L; GRAY, M E

    1959-08-01

    Single intravenous injections of Shear's polysaccharide in varying dosages invariably produced an elevation in the levels of the total serum lipides 24 hours after injection of endotoxin. The total serum cholesterol and lipide phosphorus were also affected, although they did not change with smaller doses of endotoxin and were rarely elevated to the same degree as were the total serum lipides. The degree of elevation of the serum lipides was apparently related to the amount of endotoxin injected up to a certain point, beyond which there was no further increase. There were two types of response to endotoxin by the serum lipides, a moderate increase and an uncontrolled increase. Higher dosages of endotoxin and fasting apparently increased the incidence of the latter response. No direct correlation could be made between serum lipide responses and histologic evidence typical of the generalized Shwartzman reaction following this regimen of endotoxin injection. The Shwartzman reaction did occur with greater frequency and with lower dosages of endotoxin in fasted animals. Animals given repeated injections of endotoxin showed an initial increase in serum lipides followed by a progressive decrease to normal levels as tolerance to the febrile action of endotoxin appeared. The febrile tolerance as well as the unresponsiveness of the serum lipides to endotoxin was abolished by thorium dioxide (thorotrast) in these animals. In similar experiments a "breakthrough" of lipide unresponsiveness to endotoxin was obtained by increasing the amount of endotoxin injected. Some of the implications of these results for the metabolic alterations produced by bacterial endotoxins are discussed.

  4. Determination of bacterial endotoxin (pyrogen) in radiopharmaceuticals by the gel clot method. Validation; Determinacao de endotoxina bacteriana (pirogenio) em radiofarmacos pelo metodo de formacao de gel. Validacao

    Energy Technology Data Exchange (ETDEWEB)

    Fukumori, Neuza Taeko Okasaki

    2008-07-01

    Before the Limulus amebocyte lysate (LAL) test, the only available means of pirogenicity testing for parenteral drugs and medical devices was the United States Pharmacopoeia (USP) rabbit pyrogen test. Especially for radiopharmaceuticals, the LAL assay is the elective way to determine bacterial endotoxin. The aim of this work was to validate the gel clot method for some radiopharmaceuticals without measurable interference. The FDA's LALTest guideline defines interference as a condition that causes a significant difference between the endpoints of a positive water control and positive product control series using a standard endotoxin. Experiments were performed in accordance to the USP bacterial endotoxins test in the {sup 131}I- m-iodobenzylguanidine; the radioisotopes Gallium-67 and Thallium-201; the lyophilized reagents DTPA, Phytate, GHA, HSA and Colloidal Tin. The Maximum Valid Dilution (MVD) was calculated for each product based upon the clinical dose of the material and a twofold serial dilution below the MVD was performed in duplicate to detect interferences. The labeled sensitivity of the used LAL reagent was 0.125 EU mL{sup -1} (Endotoxin Units per milliliter). For validation, a dilution series was performed, a twofold dilution of control standard endotoxin (CSE) from 0.5 to 0.03 EU mL{sup -1}, to confirm the labeled sensitivity of the LAL reagent being tested in sterile and non pyrogenic water, in quadruplicate. The same dilution series was performed with the CSE and the product in the 1:100 dilution factor, in three consecutive batches of each radiopharmaceutical. The products {sup 131}I-m-iodobenzylguanidine, Gallium-67, Thallium-201, DTPA, HSA and Colloidal Tin were found compatible with the LAL test at a 1:100 dilution factor. Phytate and GHA showed some interference in the gel clot test. Other techniques to determine endotoxins as the chromogenic (color development) and the turbidimetric test (turbidity development), were also assessed to get

  5. Innate immune defenses exhibit circadian rhythmicity and differential temporal sensitivity to a bacterial endotoxin in Nile tilapia (Oreochromis niloticus)

    DEFF Research Database (Denmark)

    Lazado, Carlo Cabacang; Skov, Peter Vilhelm; Pedersen, Per Bovbjerg

    2016-01-01

    The present study investigated the daily dynamics of humoral immune defenses and the temporal influence in the sensitivity of these responses to a bacterial endotoxin in Nile tilapia (Oreochromis niloticus). The first experiment subjected the fish to two photoperiod conditions, 12L:12D (LD) and 0L...... exposed at ZT15. Taken together, this study shows that several key components of humoral immunity in tilapia exhibit circadian rhythms and adapt to photoperiodic changes. Further, results of the bacterial endotoxin challenge suggest that responsiveness of serum humoral factors to a biological insult...

  6. Detection of bacterial endotoxin in food: New planar interdigital sensors based approach

    KAUST Repository

    Abdul Rahman, Mohd Syaifudin

    2013-02-01

    Food poisoning caused by endotoxins or Lipopolysaccharide (LPS) are associated with Gram-negative bacteria. Two major food-borne pathogens, Escherichia coli and Salmonella are examples of Gram-negative bacteria which cause a large number of outbreaks of food poisoning. New types of planar interdigital sensors have been fabricated with different coating materials to assess their response to endotoxins. A carboxyl-functional polymer, APTES (3-Aminopropyltriethoxysilane) and Thionine were chosen to be coated onto FR4 interdigital sensors. The chosen coating materials have carboxylic or amine functional groups, which were optimized to be stable in water. All coated sensors were immobilized with PmB (Polymyxin B) which has specific binding properties to LPS. The sensors were tested with different concentrations of LPS O111:B4, ranging from 0.1 to 1000 μg/ml. Analyses of sensors\\' performance were based on the impedance spectroscopy method. The impedance spectra were modeled using a constant phase-element (CPE) equivalent circuit, and a principal component analysis (PCA) was used for data classification. Sensor coated with APTES has shown better selectivity for LPS detection. The experiments were repeated by coating APTES and immobilizing PmB to a new improve designed of novel interdigital sensors (thin film silicon based sensors). These sensors were observed to have better sensitivity and selectivity to the target biomolecules of LPS. Further experiments were conducted to study the effect of different coating thickness on sensor sensitivity, selectivity and stability. Different food samples contaminated with endotoxin were also tested to verify that the interdigital sensing approach is able to be used for endotoxin detection. © 2012 Elsevier Ltd. All rights reserved.

  7. A rapid kinetic chromogenic method for quantification of bacterial endotoxins in lyophilized reagents for labeling with 99mTc radiopharmaceuticals

    International Nuclear Information System (INIS)

    Fukumori, Neuza T.O.; Campos, Domingos G.; Silva, Laercio; Fernandes, Adriana V.; Mengatti, Jair; Silva, Constancia P.G.; Matsuda, Margareth M.N.

    2009-01-01

    A rapid quantitative kinetic chromogenic test in an automated Portable Test System (PTS) has been developed for determination of bacterial endotoxins in water, in-process and end-products using the Limulus amebocyte lysate (LAL). The aim of this work was to validate the method for lyophilized reagents for labeling with 99m Tc radiopharmaceuticals with no interfering factors. Experiments were performed in three consecutive batches of the lyophilized reagents Methylenediphosphonic Acid (MDP) and Pyrophosphate (PYRO) produced at IPEN-CNEN/ SP using the PTS from Endosafe, Inc. TM , Charleston, SC. The Maximum Valid Dilution (MVD) was calculated to establish the extent of dilution to avoid interfering test conditions (MVD=500). Better results were obtained above 1:20 dilution factor for MDP and 1:100 for PYRO. The parameters of coefficient correlation (R) -0.980, RPPC between 50 - 200% and coefficient variation (CV) of the samples less than 25% were satisfied and the endotoxin concentration was lower than the lowest concentration of the standard curve (0.05 EU mL -1 ), therefore less than the established limit in pharmacopoeias. The PTS is a rapid, simple and accurate technique using the quantitative kinetic chromogenic method for bacterial endotoxin determination. For this reason, it is very practical in the radiopharmaceutical area and it trends to be the method of choice for the pyrogen test. For MDP and PYRO, the validation was successfully performed. (author)

  8. Valoración de endotoxinas bacterianas en el inyectable ácido zoledrónico mediante la prueba de lisado del amebocito de Limulus Assessment of bacterial endotoxins in Zoledronic acid injectable drug by using Limulus amebocyte lysate test

    Directory of Open Access Journals (Sweden)

    Nancy Burguet Lago

    2012-09-01

    Full Text Available Objetivo: valorar las endotoxinas bacterianas por la técnica del lisado del amebocito de Limulus para el producto inyectable ácido zoledrónico, por el método de gelificación. Métodos: el ensayo se realizó mediante dos pruebas: 1 confirmación de la sensibilidad del lisado etiquetado, para lo cual se preparó una curva estándar con diluciones seriadas dobles de endotoxina por cuadruplicado; y 2 el ensayo del producto de inhibición, en el que se prepararon diluciones seriadas dobles de endotoxina con agua apirogénica y con las muestras de los lotes a ensayar sin sobrepasar la máxima dilución válida. Se determinó el punto final y se calculó la media geométrica. Se definió la dilución de trabajo, la cual se validó por cuadruplicado en tres lotes consecutivos. Resultados: la sensibilidad del lisado resultó 0,03125 UE/mL. La máxima dilución válida fue de 112 UE/mL y la dilución de trabajo 1/100. La cantidad de endotoxinas bacterianas presentes en tres lotes del producto inyectable no sobrepasó el límite establecido, por lo que cumplió con las especificaciones de calidad establecidas para el ensayo. Conclusión: la estandarización de las condiciones del método por gelificación, hace que este resulte eficaz, confiable, rápido y de fácil ejecución, por lo que puede emplearse como ensayo de rutina en el control de la calidad del inyectable analizado.Objective: To asses the presence of bacterial endotoxins in Zoledronic Acid injectable drug by using the Limulus amebocyte lysate test, particularly by the gelling procedure. Methods: The assay was performed in two tests: the first was the confirmation of labeled lysate sensitivity by preparing a standard curve with serial double dilutions of endotoxins four times, and the second was the inhibition product test in which serial double dilutions of endotoxins were prepared with apyrogenic water and with samples from the batches to be tested, without exceeding the maximum valid

  9. Endotoxin dosage in sepsis

    Directory of Open Access Journals (Sweden)

    Vincenzo Rondinelli

    2012-03-01

    Full Text Available Introduction. Endotoxin, a component of the cell wall of Gram-negative bacteria is a major contributor to the pathogenesis of septic shock and multiple organ failure (MOF. Its entry into the bloodstream stimulates monocytes/macrophages which once activated produce and release cytokines, nitric oxide and other mediators that induce systemic inflammation, endothelial damage, organ dysfunction, hypotension (shock and MOF.The aim of this study is to evaluate the usefulness of a quantitative test for the dosage of endotoxin to determine the risk of severe Gram-negative sepsis. Materials and methods. In the period January 2009 - June 2011 we performed 897 tests for 765 patients, mostly coming from the emergency room and intensive care, of which 328 (43% women (mean age 53 and 437 (57% male (mean age 49. Fifty-nine patients, no statistically significant difference in sex, were monitored by an average of two determinations of EA.All patients had procalcitonin values significantly altered.The kit used was EAA (Endotoxin Activity Assay Estor Company, Milan, which has three ranges of endotoxin activity (EA: low risk of sepsis if <0.40 units, medium if between 0.40 and 0.59; high if 0.60. Results. 78 out of 765 patients (10% had a low risk, 447 (58% a medium risk and 240 (32% a high risk.The dosage of EA, combined with that of procalcitonin, has allowed a more targeted antibiotic therapy. Six patients in serious clinical conditions were treated by direct hemoperfusion with Toraymyxin, a device comprising a housing containing a fiber polypropylene and polystyrene with surface-bound polymyxin B, an antibiotic that removes bacterial endotoxins from the blood. Conclusions.The test is useful in risk stratification as well as Gram negative sepsis, to set and monitor targeted therapies, also based on the neutralization of endotoxin.

  10. Mediated effect of endotoxin and lead upon hepatic metabolism

    International Nuclear Information System (INIS)

    Kuttner, R.E.; Ebata, T.; Schumer, W.

    1984-01-01

    A test was made of the possibility that gram-negative bacterial cell wall lipopolysaccharides acted directly on key glucoregulatory enzymes in rat liver cytosol to cause the characteristic hypoglycemia of severe endotoxemia. Fasted male rats were sensitized to endotoxin by the simultaneous intravenous injection of lead acetate. The minimum systemic dosage of endotoxin necessary to perturb the normal pattern of hepatic glycolytic intermediates was determined by serial testing with diminishing dosages of endotoxin. The hepatocyte concentration of endotoxin was then calculated from this minimum dosage by use of literature data on the fraction of endotoxin delivered to liver cells after a systemic intravenous injection of radiochromium labeled lipopolysaccharides. Accepting a molecular weight of 118,000 daltons for the smallest endotoxin monomer capable of evoking a physiologic response, the molar amount of endotoxin present in 1 gram of hepatocytes was readily calculated. The concentration of glucoregulatory enzymes in parenchymal cells was then estimated from other literature sources. It was found that the amount of endotoxin in the hepatocytes was insufficient to combine directly with even 1 per cent of the quantity of a single key glucoregulatory enzyme in liver parenchyma. Since a one to one stoichiometric reaction between endotoxin and enzyme could not occur in the liver cytosol, a direct interaction mechanism between agonist and biocatalyst can be ruled out. It is concluded that bacterial endotoxin must act on hepatic glucoregulation by an indirect mechanism presumably based upon the release and operation of mediators

  11. Detection of endotoxin in the plasma of patients with gram-negative bacterial sepsis by the Limulus amoebocyte lysate assay.

    Science.gov (United States)

    Pearson, F C; Dubczak, J; Weary, M; Bruszer, G; Donohue, G

    1985-01-01

    A total of 120 Limulus amoebocyte lysate (LAL) determinations were made on plasma obtained from normal, healthy human blood donors. Results demonstrated a mean endotoxin level in blood of 0.02 to 1.57 pg/ml. The amount of Escherichia coli endotoxin added to human plasma samples can be quantitated by both nephelometry and turbidimetry. Endotoxin-spiked samples were shown to be significantly different from unspiked samples. When plasma samples were collected from 45 patients hospitalized at three centers, a strong association was demonstrated between a positive Limulus amoebocyte lysate assay and a septic condition. Sensitivity, specificity, and false-positive and false-negative rates for the Limulus amoebocyte lysate assay as a diagnostic test for gram-negative bacteremia were estimated. PMID:4008617

  12. Development of an in vitro Endotoxin Test for Monoolein–Water ...

    African Journals Online (AJOL)

    Purpose: Drugs that are administered by parenteral route must be apyrogenic. The aim of this study was to develop an in vitro endotoxin test for liquid crystalline gels for use as implants, using a monoolein–water liquid crystalline gel as a model. Methods: The gel-clot technique was used. The gel was dissolved first in ...

  13. Importance of bacterial endotoxin (LPS in endodontics A importância da endotoxina bacteriana (LPS na endodontia atual

    Directory of Open Access Journals (Sweden)

    Mario Roberto Leonardo

    2004-06-01

    Full Text Available New knowledge of the structure and biological activity of endotoxins (LPS has revolutionized concepts concerning their mechanisms of action and forms of inactivation. Since the 1980's, technological advances in microbiological culture and identification have shown that anaerobic microorganisms, especially Gram-negative, predominate in root canals of teeth with pulp necrosis and radiographically visible chronic periapical lesions. Gram-negative bacteria not only have different factors of virulence and generate sub-products that are toxic to apical and periapical tissues, as also contain endotoxin (LPS on their cell wall. This is especially important because endotoxin is released during multiplication or bacterial death, causing a series of biological effects that lead to an inflammatory reaction and resorption of mineralized tissues. Thus, due to the role of endotoxin in the pathogenesis of periapical lesions, we reviewed the literature concerning the biological activity of endotoxin and the relevance of its inactivation during treatment of teeth with pulp necrosis and chronic periapical lesion.O conhecimento mais aprofundado sobre a estrutura e atividade biológica das endotoxinas (LPS revolucionou os conceitos sobre seu mecanismo de ação e formas de inativação. A partir da década de 80, os avanços tecnológicos na cultura e identificação microbiológica demonstraram que, em canais radiculares de dentes portadores de necrose pulpar e lesão periapical crônica, visível radiograficamente, predominam microrganismos anaeróbios, particularmente os gram-negativos. Como se sabe, os microrganismos gram-negativos, além de possuírem diferentes fatores de virulência e gerarem produtos e sub-produtos tóxicos aos tecidos apicais e periapicais, contêm endotoxina em sua parede celular. Esse conhecimento é particularmente importante, uma vez que a endotoxina é liberada durante a multiplicação ou morte bacteriana, exercendo uma série de

  14. Plasma endotoxin activity in kangaroos with oral necrobacillosis (lumpy jaw disease) using an automated handheld testing system.

    Science.gov (United States)

    Sotohira, Yukari; Suzuki, Kazuyuki; Sasaki, Haruka; Sano, Tadashi; Tsuchiya, Masakazu; Suzuki, Yohko; Shimamori, Toshio; Tsukano, Kenji; Sato, Ayano; Yokota, Hiroshi; Asakawa, Mitsuhiko

    2016-07-01

    The aim of the present study was to evaluate the reliability and effectiveness of directly determining endotoxin activity in plasma samples from kangaroos with lumpy jaw disease (LJD, n=15) and healthy controls (n=12). Prior to the present study, the ability of the commercially available automated handheld portable test system (PTS(TM)) to detect endotoxin activity in kangaroo plasma was compared with that of the traditional LAL-kinetic turbidimetric (KT) assay. Plasma samples, which were obtained from endotoxin-challenged cattle, were diluted 1:20 in endotoxin-free water and heated to 80°C for 10 min. The performance of the PTS(TM) was not significantly different from that of the traditional LAL-based assay. The data obtained using PTS(TM) correlated with those using KT (r(2)=0.963, Pkangaroos with systemic inflammation caused by oral necrobacillosis and identified plasma endotoxin activity as a sensitive marker of systemic inflammation in kangaroos with LJD. Based on ROC curves, we proposed a diagnostic cut-off point for endotoxin activity of >0.22 EU/ml for the identification of LJD. Our results indicate that the assessment of plasma endotoxin activity is a promising diagnostic tool for determining the outcome of LJD in captive macropods.

  15. Role of Bacterial Endotoxins of Intestinal Origin in Rat Heat Stress Mortality

    Science.gov (United States)

    1982-01-19

    the effect of increased survival associated Received 19 January 1982; accepted in final form 15 July 1982. REFERENCES 1. ALTURA , B. M., AND S. G...Limulus assay for endotoxin. N. Engi. J. Med. 289: 484- 1414-1419, 1968. 485, 1973. 2. ALTURA , B. M., AND S. G. HERSHEY. Acute intestinal ischemia 9...and chronic lung injury. J. App. Physiol: Soc. 10: 361-371, 1971. Respirat. Environ. Exercise Physiol. 47: 577-581, 1979. 3. ALTURA , B. M., C. THAW

  16. Improved detection limits of bacterial endotoxins using new type of planar interdigital sensors

    KAUST Repository

    Syaifudin, A. R Mohd

    2012-10-01

    New types of planar interdigital sensors were fabricated by photolithography and etching techniques on a Silicon/Silicon Dioxide (Si/SiO2) wafer (single side polished). The sensors were then coated with APTES (3-aminopropyltrietoxysilane) a cross linker used to bind Polymyxin B (PmB) molecules on electrodes surface. PmB is an antimicrobial peptide produced by the Gram-positive bacterium-Bacillus which has specific binding properties to Lipopolysaccharide (LPS). This paper will discuss the fabrication process, coating and immobilization procedures and analysis of sensors\\' performance based on Impedance Spectroscopy method. The sensor sensitivity was compared to standard ToxinSensor Chromogenic LAL Endotoxin Assay Kit for verification. © 2012 IEEE.

  17. Measurement of endotoxin levels in blood of hemodialysis Patients by 'Lal' test and comparision of its efficacy with blood culture

    Directory of Open Access Journals (Sweden)

    Gh Vazirzadeh

    2006-01-01

    Full Text Available Introduction: Presently, bacteremia is the principal cause of morbidity in patients undergoing hemodialysis. Gram-negative bacteria account for approximately 50 percent of documented infections. Endotoxins released during lysis of gram negative bacteremia result in inflammatory and defense response by the body and if not treated promptly result in septic shock and ultimately death of the patient. This study describes the detection of endotoxins in blood of patients with bacteremia due to gram - negative bacteria by LAL test. Method: Blood samples of 278 hemodialysis patients were analyzed in this study and pathogens were isolated from blood culture samples. Then, their antibiotic sensitivity was determined. In patients with positive blood culture, endotoxin levels were measured by LAL-test. Results: Frequency of bacteremia in patients was 13.6% . The prevalence of gram – negative bacteremia was 44.7%. E coli were the major pathogens, while staphylococcus aureus was the most common gram positive bacterium. Endotoxin was detected in 15 patients (3.8 ± 1.08 EU/ml . The sensitivity and specificity of endotoxins for gram – negative bacteremia were 88% and 95%, respectively. Conclusion: The results indicate that the LAL method is a fast, sensitive and simple method. There was no significant difference between the results of blood culture and LAL – test ( P > 0.05 .

  18. Detection of irradiated chicken and fish meats by the determination of Gram negative bacterial count and bacterial endotoxins

    International Nuclear Information System (INIS)

    Badr, H.M.

    2010-01-01

    The aim of this investigation was to study the possibility of detecting irradiated chicken and fish meats by the determination of Gram negative bacteria combined with the determination of endotoxin concentrations. Samples of chicken breast with skin, skinless chicken breast and eviscerated Bolti fish (Tilabia nilotica) were irradiated at room temperature at doses of 0, 1.5 and 3 kGy followed by storage at refrigeration temperature (4 ± 1 degree C) for 12 days or frozen storage at -18 degree C for 60 days. Furthermore, other samples of chicken and Bolti fish were irradiated in the frozen sate at doses of 0, 3, and 7 kGy followed by frozen storage at - 18 degree C for 60 days. Then the enumeration of Gram negative bacteria in conjunction with the determination of endotoxin concentrations were carried out for both irradiated and non-irradiated samples post treatments and during storage in addition to the discovery of Pseudomonas spp. The obtained results showed that chicken and fish samples irradiated at dose of 1.5 kGy could be identified during refrigerated storage for 6 and 9 days, respectively, while all samples irradiated at dose of 3 kGy were identifiable during 12 days of refrigerated storage. Moreover, all irradiated and frozen stored samples were identifiable during their frozen storage (- 18 degree C). The absence of Pseudomonads in all irradiated samples may aid in the differentiation of irradiated and non-irradiated samples especially during refrigerated storage. This method can be applied as a general screening method to predict the possible treatment of chicken and fish meats by ionizing radiation

  19. Endotoxin Contamination in Nanomaterials Leads to the Misinterpretation of Immunosafety Results

    Directory of Open Access Journals (Sweden)

    Yang Li

    2017-05-01

    Full Text Available Given the presence of engineered nanomaterials in consumers’ products and their application in nanomedicine, nanosafety assessment is becoming increasingly important. In particular, immunosafety aspects are being actively investigated. In nanomaterial immunosafety testing strategies, it is important to consider that nanomaterials and nanoparticles are very easy to become contaminated with endotoxin, which is a widespread contaminant coming from the Gram-negative bacterial cell membrane. Because of the potent inflammatory activity of endotoxin, contaminated nanomaterials can show inflammatory/toxic effects due to endotoxin, which may mask or misidentify the real biological effects (or lack thereof of nanomaterials. Therefore, before running immunosafety assays, either in vitro or in vivo, the presence of endotoxin in nanomaterials must be evaluated. This calls for using appropriate assays with proper controls, because many nanomaterials interfere at various levels with the commercially available endotoxin detection methods. This also underlines the need to develop robust and bespoke strategies for endotoxin evaluation in nanomaterials.

  20. Possible mechanism for preterm labor associated with bacterial infection. I. Stimulation of phosphoinositide metabolism by endotoxin in endometrial fibroblasts

    International Nuclear Information System (INIS)

    Khan, A.A.; Imai, A.; Tamaya, T.

    1990-01-01

    Growing evidence suggests an association between intra-amniotic infection and premature initiation of parturition. We recently demonstrated that some factor(s) including endotoxin produced by the organism stimulates endogenous phospholipase A2 resulting in liberation of arachidonic acid and prostaglandin formation. The studies presented in this report were designated to evaluate the mechanism for endotoxin to stimulate phospholipase A2 using human endometrial fibroblasts. Exposure of the fibroblasts to endotoxin from Escherichia coli in the presence of [ 32 P] phosphate increased 32 P-labeling of phosphatidic acid (PA) and phosphatidyl-inositol (PI) in a dose-dependent and a time-dependent manners. The PA labeling occurred without a measurable lag time. These findings demonstrate that the endotoxin stimulates phosphoinositide metabolism in human endometrial fibroblasts by a receptor-mediated mechanism. Membrane phosphoinositide turnover stimulated by endotoxin results in cytosolic Ca 2+ increment, liberation of arachidonic acid, which may be involved in the initiation of parturition

  1. TRPA1 channels mediate acute neurogenic inflammation and pain produced by bacterial endotoxins

    Science.gov (United States)

    Meseguer, Victor; Alpizar, Yeranddy A.; Luis, Enoch; Tajada, Sendoa; Denlinger, Bristol; Fajardo, Otto; Manenschijn, Jan-Albert; Fernández-Peña, Carlos; Talavera, Arturo; Kichko, Tatiana; Navia, Belén; Sánchez, Alicia; Señarís, Rosa; Reeh, Peter; Pérez-García, María Teresa; López-López, José Ramón; Voets, Thomas; Belmonte, Carlos; Talavera, Karel; Viana, Félix

    2014-01-01

    Gram-negative bacterial infections are accompanied by inflammation and somatic or visceral pain. These symptoms are generally attributed to sensitization of nociceptors by inflammatory mediators released by immune cells. Nociceptor sensitization during inflammation occurs through activation of the Toll-like receptor 4 (TLR4) signalling pathway by lipopolysaccharide (LPS), a toxic by-product of bacterial lysis. Here we show that LPS exerts fast, membrane delimited, excitatory actions via TRPA1, a transient receptor potential cation channel that is critical for transducing environmental irritant stimuli into nociceptor activity. Moreover, we find that pain and acute vascular reactions, including neurogenic inflammation (CGRP release) caused by LPS are primarily dependent on TRPA1 channel activation in nociceptive sensory neurons, and develop independently of TLR4 activation. The identification of TRPA1 as a molecular determinant of direct LPS effects on nociceptors offers new insights into the pathogenesis of pain and neurovascular responses during bacterial infections and opens novel avenues for their treatment.

  2. A practical approach for the validation of sterility, endotoxin and potency testing of bone marrow mononucleated cells used in cardiac regeneration in compliance with good manufacturing practice

    Directory of Open Access Journals (Sweden)

    Gola Mauro

    2009-09-01

    Full Text Available Abstract Background Main scope of the EU and FDA regulations is to establish a classification criterion for advanced therapy medicinal products (ATMP. Regulations require that ATMPs must be prepared under good manufacturing practice (GMP. We have validated a commercial system for the determination of bacterial endotoxins in compliance with EU Pharmacopoeia 2.6.14, the sterility testing in compliance with EU Pharmacopoeia 2.6.1 and a potency assay in an ATMP constituted of mononucleated cells used in cardiac regeneration. Methods For the potency assay, cells were placed in the upper part of a modified Boyden chamber containing Endocult Basal Medium with supplements and transmigrated cells were scored. The invasion index was expressed as the ratio between the numbers of invading cells relative to cell migration through a control insert membrane. For endotoxins, we used a commercially available system based on the kinetic chromogenic LAL-test. Validation of sterility was performed by direct inoculation of TSB and FTM media with the cell product following Eu Ph 2.6.1 guideline. Results and discussion The calculated MVD and endotoxin limit were 780× and 39 EU/ml respectively. The 1:10 and 1:100 dilutions were selected for the validation. For sterility, all the FTM cultures were positive after 3 days. For TSB cultures, Mycetes and B. subtilis were positive after 5 and 3 days respectively. The detection limit was 1-10 colonies. A total of four invasion assay were performed: the calculated invasion index was 28.89 ± 16.82% (mean ± SD. Conclusion We have validated a strategy for endotoxin, sterility and potency testing in an ATMP used in cardiac regeneration. Unlike pharmaceutical products, many stem-cell-based products may originate in hospitals where personnel are unfamiliar with the applicable regulations. As new ATMPs are developed, the regulatory framework is likely to evolve. Meanwhile, existing regulations provide an appropriate structure for

  3. A practical approach for the validation of sterility, endotoxin and potency testing of bone marrow mononucleated cells used in cardiac regeneration in compliance with good manufacturing practice.

    Science.gov (United States)

    Soncin, Sabrina; Lo Cicero, Viviana; Astori, Giuseppe; Soldati, Gianni; Gola, Mauro; Sürder, Daniel; Moccetti, Tiziano

    2009-09-08

    Main scope of the EU and FDA regulations is to establish a classification criterion for advanced therapy medicinal products (ATMP). Regulations require that ATMPs must be prepared under good manufacturing practice (GMP). We have validated a commercial system for the determination of bacterial endotoxins in compliance with EU Pharmacopoeia 2.6.14, the sterility testing in compliance with EU Pharmacopoeia 2.6.1 and a potency assay in an ATMP constituted of mononucleated cells used in cardiac regeneration. For the potency assay, cells were placed in the upper part of a modified Boyden chamber containing Endocult Basal Medium with supplements and transmigrated cells were scored. The invasion index was expressed as the ratio between the numbers of invading cells relative to cell migration through a control insert membrane. For endotoxins, we used a commercially available system based on the kinetic chromogenic LAL-test. Validation of sterility was performed by direct inoculation of TSB and FTM media with the cell product following Eu Ph 2.6.1 guideline. The calculated MVD and endotoxin limit were 780x and 39 EU/ml respectively. The 1:10 and 1:100 dilutions were selected for the validation. For sterility, all the FTM cultures were positive after 3 days. For TSB cultures, Mycetes and B. subtilis were positive after 5 and 3 days respectively. The detection limit was 1-10 colonies. A total of four invasion assay were performed: the calculated invasion index was 28.89 +/- 16.82% (mean +/- SD). We have validated a strategy for endotoxin, sterility and potency testing in an ATMP used in cardiac regeneration. Unlike pharmaceutical products, many stem-cell-based products may originate in hospitals where personnel are unfamiliar with the applicable regulations. As new ATMPs are developed, the regulatory framework is likely to evolve. Meanwhile, existing regulations provide an appropriate structure for ensuring the safety and efficacy of the next generation of ATMPs. Personnel

  4. Variation in the ovine cortisol response to systemic bacterial endotoxin challenge is predominantly determined by signalling within the hypothalamic-pituitary-adrenal axis

    International Nuclear Information System (INIS)

    You Qiumei; Karrow, Niel A.; Cao Honghe; Rodriguez, Alexander; Mallard, Bonnie A.; Boermans, Herman J.

    2008-01-01

    Bi-directional communication between the neuroendocrine and immune systems is designed, in part, to maintain or restore homeostasis during physiological stress. Exposure to endotoxin during Gram-negative bacterial infection for example, elicits the release of pro-inflammatory cytokines that activate the hypothalamic-pituitary-adrenal axis (HPAA). The secretion of adrenal glucocorticoids subsequently down regulates the host inflammatory response, minimizing potential tissue damage. Sequence and epigenetic variants in genes involved in regulating the neuroendocrine and immune systems are likely to contribute to individual differences in the HPAA response, and this may influence the host anti-inflammatory response to toxin exposure and susceptibility to inflammatory disease. In this study, high (HCR) and low (LCR) cortisol responders were selected from a normal population of 110 female sheep challenged iv with Escherichia coli endotoxin (400 ng/kg) to identify potential determinants that contribute to variation in the cortisol response phenotype. This phenotype was stable over several years in the HCR and LCR animals, and did not appear to be attributed to differences in expression of hepatic immune-related genes or systemic pro-inflammatory cytokine concentrations. Mechanistic studies using corticotrophin-releasing factor (0.5 μg/kg body weight), arginine vasopressin (0.5 μg/kg), and adrenocorticotropic hormone (0.5 μg/kg) administered iv demonstrated that variation in this phenotype is largely determined by signalling within the HPAA. Future studies will use this ovine HCR/LCR model to investigate potential genetic and epigenetic variants that may contribute to variation in cortisol responsiveness to bacterial endotoxin

  5. Genetic engineering approach to develop next-generation reagents for endotoxin quantification

    OpenAIRE

    Mizumura, Hikaru; Ogura, Norihiko; Aketagawa, Jun; Aizawa, Maki; Kobayashi, Yuki; Kawabata, Shun-ichiro; Oda, Toshio

    2016-01-01

    The bacterial endotoxin test, which uses amebocyte lysate reagents of horseshoe crab origin, is a sensitive, reproducible and simple assay to measure endotoxin concentration. To develop sustainable raw materials for lysate reagents that do not require horseshoe crabs, three recombinant protease zymogens (factor C, derived from mammalian cells; factor B; and the proclotting enzyme derived from insect cells) were prepared using a genetic engineering technique. Recombinant cascade reagents (RCRs...

  6. Development of an in vitro Endotoxin Test for Monoolein–Water ...

    African Journals Online (AJOL)

    Erah

    Loaded Monoolein Gel Intended to Treat. Chronic Osteomyelitis. J. Pharmacol. Toxicol.,. 2008; 3(5): 386-393. 13 Magalahaes PO, Lopes AM, Mazolla PG, Rangel-. Yagui C, Penna TCV, Pessoa Jr A. Methods of. Endotoxins. Removal from. Biological. Preparations: a Review. J Pharm Pharmaceut. Sci. 2007; 10(3): 388-404.

  7. Endotoxin detection--from limulus amebocyte lysate to recombinant factor C.

    Science.gov (United States)

    Ding, Jeak Ling; Ho, Bow

    2010-01-01

    Gram negative bacterial endotoxin is a biological pyrogen that causes fever when introduced intravenously. The endotoxin, also known as lipopolysaccharide (LPS), is found in the outer membrane of Gram-negative bacteria. During Gram-negative sepsis, endotoxin stimulates host macrophages to release inflammatory cytokines. However, excessive inflammation causes multiple organ failure and death. Endotoxins, which are ubiquitous pathogenic molecules, are a bane to the pharmaceutical industry and healthcare community. Thus early and sensitive detection of endotoxin is crucial to prevent endotoxaemia. The limulus amebocyte lysate (LAL) has been widely used for ~30 years for the detection of endotoxin in the quality assurance of injectable drugs and medical devices. The LAL constitutes a cascade of serine proteases which are triggered by trace levels of endotoxin, culminating in a gel clot at the end of the reaction. The Factor C, which normally exists as a zymogen, is the primer of this coagulation cascade. In vivo, Factor C is the perfect biosensor, which alerts the horseshoe crab of the presence of a Gram-negative invader. The hemostatic end-point entraps the invader, killing it and limiting further infection. However, as an in vitro endotoxin detection tool, variations in the sensitivity and specificity of LAL to endotoxin, and the dwindling supply of horseshoe crabs are posing increasing challenges to the biotechnology industry. This has necessitated the innovation of an alternative test for endotoxin. Thus, Factor C became the obvious, albeit tricky target for the recombinant technology effort. This chapter documents the backwater of mining the natural blood lysate of the endangered species to the monumental effort of genetic engineering, to produce recombinant Factor C (rFC). The rFC is a 132 kDa molecule, which was produced as a proenzyme inducible by the presence of trace levels of endotoxin. The rFC forms the basis of the "PyroGene" kit, which is a novel micro

  8. Recent advances in biosensor based endotoxin detection.

    Science.gov (United States)

    Das, A P; Kumar, P S; Swain, S

    2014-01-15

    Endotoxins also referred to as pyrogens are chemically lipopolysaccharides habitually found in food, environment and clinical products of bacterial origin and are unavoidable ubiquitous microbiological contaminants. Pernicious issues of its contamination result in high mortality and severe morbidities. Standard traditional techniques are slow and cumbersome, highlighting the pressing need for evoking agile endotoxin detection system. The early and prompt detection of endotoxin assumes prime importance in health care, pharmacological and biomedical sectors. The unparalleled recognition abilities of LAL biosensors perched with remarkable sensitivity, high stability and reproducibility have bestowed it with persistent reliability and their possible fabrication for commercial applicability. This review paper entails an overview of various trends in current techniques available and other possible alternatives in biosensor based endotoxin detection together with its classification, epidemiological aspects, thrust areas demanding endotoxin control, commercially available detection sensors and a revolutionary unprecedented approach narrating the influence of omics for endotoxin detection. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Gender Difference in Bacteria Endotoxin-Induced Inflammatory and Anorexic Responses.

    Science.gov (United States)

    Kuo, Shiu-Ming

    2016-01-01

    Inflammation-related anorexic response has been observed in systemic diseases as well as in localized infection and is an important issue in patient care. We tested the hypothesis that upon the same endotoxin exposure, males have more severe inflammatory responses and thus suffer from more negative effect on appetite. Ten-week old male and female mice were compared in their plasma levels of pro-inflammatory cytokines after a body weight-based i.p. injection of bacterial endotoxin lipopolysaccharide. Male mice consistently showed significantly higher levels of IL6 and TNFα than female mice. The difference was observed starting at 3 hours after the systemic endotoxin exposure. It was independent of the level of endotoxin dosage and of the genotype of the anti-inflammatory cytokine, IL10. Interestingly, endotoxin-injected male mice also had significantly higher plasma IL10 levels compared to the female mice. Pre-puberty young mice showed no gender differences in the plasma levels of IL6, TNFα and IL10. Their cytokine levels were mostly between that of the adult males and females. Consistent with the higher inflammatory response in male mice, the endotoxin exposure also led to significantly more appetite loss in male mice at a range of doses in two strains of mice. Saline injection in the absence of endotoxin affected neither the cytokine levels nor the appetite. Although a direct mechanistic link between inflammation parameters and appetite was not addressed here, the results support that male gender could be a risk factor for higher pro-inflammatory cytokines and anorexic response after the endotoxin exposure.

  10. Estimativa da incerteza em ensaio de detecção de endotoxina bacteriana pelo método de gelificação Estimation of uncertainty in the detection of bacterial endotoxin by gel-clot method

    Directory of Open Access Journals (Sweden)

    Felipe Rebello Lourenço

    2005-12-01

    Full Text Available Desde a publicação da ISO 17025:1999, o interesse em métodos para estimativa da incerteza em ensaios qualitativos, do tipo "passa/não passa", têm ganho grande importância. Uma forma de estimar e informar a incerteza deste tipo de ensaio é o uso das probabilidades de respostas-falsas, particularmente falsos-positivos e falsos-negativos, determinados a partir do teorema de Bayes. O objetivo deste artigo é estabelecer um método para a estimativa de incerteza em ensaios de detecção de endotoxina bacteriana pelo método in vitro Limulus Amebocyte Lysate (LAL. Considerando a confirmação da sensibilidade do LAL e a validação do teste, a probabilidade de uma resposta falsa corresponde à soma da probabilidade dos resultados falso-negativos e falso-positivos. A partir dos resultados obtidos foi verificado que a etapa da confirmação da sensibilidade do LAL contribui para a incerteza de forma mais significativa (67,6% que a etapa de validação do teste (32,4%. Através de um procedimento simples, descrito neste artigo, e de dados obtidos a partir da confirmação da sensibilidade do LAL e validação do teste para um produto em questão é possível obter uma estimativa de incerteza razoável para o ensaio de detecção de endotoxinas bacterianas pelo método de gelificação.Since the publication of ISO 17025:1999, the interest in methods for estimation of the uncertainty in qualitative analysis, such as 'pass/fail', have became more important. The usual form of estimating and informing the uncertainty in this kind of analysis is the use of false-response rates, particularly false-positive and false-negative, determinated from Bayes theorem. The aim of this paper is establish a method for estimation of the uncertainty in the detection of bacterial endotoxins by in vitro Limulus Amebocyte Lysate (LAL test. Considering the confirmation of LAL sensitivity and the validation of the test, the probability of a false-response corresponds to the

  11. An investigation of the possibility to replace the rabbit pyrogen test by an in vitro test

    NARCIS (Netherlands)

    Gommer AM; Donders LAM; LGM

    1998-01-01

    The classical test for the detection of pyrogenic contaminations in pharmaceuticals is the rabbit pyrogen test. The most frequently occuring and most important pyrogenic contamination in biological and biotechnological pharmaceutical preparations are bacterial endotoxins, originating from the

  12. Elevated Endotoxin Levels in Human Intravenous Immunoglobulin Concentrates Caused by (1->3)-{beta}-D-Glucans.

    Science.gov (United States)

    Buchacher, Andrea; Krause, Dagmar; Wiry, Gerda; Weinberger, Josef

    2010-01-01

    Endotoxins have been measured routinely in the final product and during the production process to produce non-pyrogenic parenterals. Limulus-amoebocyte-lysate-reactive material was found in in-process samples and final product of one of Octapharma's intravenous immunoglobulin (IVIG) preparations. Limulus-amoebocyte-lysate (LAL) is activated by bacterial endotoxins and by (1→3)-β-D-glucans. The contribution of both compounds on the LAL-related signal was determined by three different approaches: (1) using a test specific for (1→3)-β-D-glucans, (2) by addition of β-glucan blocker, and (3) by the use of a recombinant endotoxin assay. It was shown that none of our IVIG concentrates contained elevated endotoxin contents but that the higher LAL reaction could be ascribed to (1→3)-β-D-glucans extracted from cellulose filter pads. The use of an endotoxin test kit highly sensitive for (1→3)-β-D-glucans might lead to false-positive results. (1→3)-β-D-glucans spike solutions did not evoke an increase of temperature in rabbits, suggesting that a pyrogenic reaction is not expected in patients. Endotoxins have been measured routinely in the final product and during the production process to produce non-pyrogenic parenterals. Limulus-amoebocyte-lysate-reactive material was found in in-process samples and final product of one of Octapharma's intravenous immunoglobulin (IVIG) preparations. Limulus-amoebocyte-lysate (LAL) is activated by bacterial endotoxins and by (1→3)-β-D-glucans. The contribution of both compounds on the LAL-related signal was determined by three different approaches: (1) using a test specific for (1→3)-β-D-glucans, (2) by addition of β-glucan blocker, and (3) by the use of a recombinant endotoxin assay. It has been shown that none of our IVIG concentrates contained elevated endotoxin contents but that the higher LAL reaction could be ascribed to (1→3)-β-D-glucans extracted from cellulose filter pads. The use of an endotoxin test kit

  13. Endotoxin removal by radio frequency gas plasma (glow discharge)

    Science.gov (United States)

    Poon, Angela

    2011-12-01

    -IR measurements were repeated after employing 3-minute RFGD treatments sequentially for more than 10 cycles to observe removal of deposited matter that correlated with diminished EU titers. The results showed that 5 cycles, for a total exposure time of 15 minutes to low-temperature gas plasma, was sufficient to reduce endotoxin titers to below 0.05 EU/ml, and correlated with concurrent reduction of major endotoxin reference standard absorption bands at 3391 cm-1, 2887 cm-1, 1646 cm -1 1342 cm-1, and 1103 cm-1 to less than 0.05 Absorbance Units. Band depletion varied from 15% to 40% per 3-minute cycle of RFGD exposure, based on peak-to-peak analyses. In some cases, 100% of all applied biomass was removed within 5 sequential 3-minute RFGD cycles. The lipid ester absorption band expected at 1725 cm-1 was not detectable until after the first RFGD cycle, suggesting an unmasking of the actual bacterial endotoxin membrane induced within the gas plasma environment. Future work must determine the applicability of this low-temperature, quick depyrogenation process to medical devices of more complicated geometry than the flat surfaces tested here.

  14. Network topologies and dynamics leading to endotoxin tolerance and priming in innate immune cells.

    Directory of Open Access Journals (Sweden)

    Yan Fu

    Full Text Available The innate immune system, acting as the first line of host defense, senses and adapts to foreign challenges through complex intracellular and intercellular signaling networks. Endotoxin tolerance and priming elicited by macrophages are classic examples of the complex adaptation of innate immune cells. Upon repetitive exposures to different doses of bacterial endotoxin (lipopolysaccharide or other stimulants, macrophages show either suppressed or augmented inflammatory responses compared to a single exposure to the stimulant. Endotoxin tolerance and priming are critically involved in both immune homeostasis and the pathogenesis of diverse inflammatory diseases. However, the underlying molecular mechanisms are not well understood. By means of a computational search through the parameter space of a coarse-grained three-node network with a two-stage Metropolis sampling approach, we enumerated all the network topologies that can generate priming or tolerance. We discovered three major mechanisms for priming (pathway synergy, suppressor deactivation, activator induction and one for tolerance (inhibitor persistence. These results not only explain existing experimental observations, but also reveal intriguing test scenarios for future experimental studies to clarify mechanisms of endotoxin priming and tolerance.

  15. Network Topologies and Dynamics Leading to Endotoxin Tolerance and Priming in Innate Immune Cells

    Science.gov (United States)

    Fu, Yan; Glaros, Trevor; Zhu, Meng; Wang, Ping; Wu, Zhanghan; Tyson, John; Li, Liwu; Xing, Jianhua

    2012-01-01

    The innate immune system, acting as the first line of host defense, senses and adapts to foreign challenges through complex intracellular and intercellular signaling networks. Endotoxin tolerance and priming elicited by macrophages are classic examples of the complex adaptation of innate immune cells. Upon repetitive exposures to different doses of bacterial endotoxin (lipopolysaccharide) or other stimulants, macrophages show either suppressed or augmented inflammatory responses compared to a single exposure to the stimulant. Endotoxin tolerance and priming are critically involved in both immune homeostasis and the pathogenesis of diverse inflammatory diseases. However, the underlying molecular mechanisms are not well understood. By means of a computational search through the parameter space of a coarse-grained three-node network with a two-stage Metropolis sampling approach, we enumerated all the network topologies that can generate priming or tolerance. We discovered three major mechanisms for priming (pathway synergy, suppressor deactivation, activator induction) and one for tolerance (inhibitor persistence). These results not only explain existing experimental observations, but also reveal intriguing test scenarios for future experimental studies to clarify mechanisms of endotoxin priming and tolerance.

  16. Cellular Effects of Endotoxin in Vitro: Mobility of Endotoxin in the Plasma Membrane of Hepatocytes and Neuroblastoma Cells

    Science.gov (United States)

    1985-01-01

    and detoxification of endotoxin. The liver is also the primary site for gluconeogenesis, ketogenesis and ureagenesis and serves a vital role in...supplying the body’s energy needs. While the effect of endotoxin on hepatic gluconeogenesis and ketogenesis has been studied in some detail (For reviews...Jr. Gluconeogenesis, ureagenesis and ketogenesis during sepsis. JPEN 4:277-285, 1980. 2. Berry, L.J. Bacterial toxins. CRC Crit. Rev. Toxicol. 5:239

  17. Endotoxins in surgical instruments of hip arthroplasty

    Directory of Open Access Journals (Sweden)

    Vania Regina Goveia

    2016-06-01

    Full Text Available Abstract OBJECTIVE To investigate endotoxins in sterilized surgical instruments used in hip arthroplasties. METHOD A descriptive exploratory study conducted in a public teaching hospital. Six types of surgical instruments were selected, namely: acetabulum rasp, femoral rasp, femoral head remover, chisel box, flexible bone reamer and femoral head test. The selection was based on the analysis of the difficulty in removing bone and blood residues during cleaning. The sample was made up of 60 surgical instruments, which were tested for endotoxins in three different stages. The EndosafeTM Gel-Clot LAL (Limulus Amebocyte Lysate method was used. RESULT There was consistent gel formation with positive analysis in eight instruments, corresponding to 13.3%, being four femoral rasps and four bone reamers. CONCLUSION Endotoxins in quantity ≥0.125 UE/mL were detected in 13.3% of the instruments tested.

  18. Use of limulus assay to compare the biological activity of peptidoglycan and endotoxin.

    Science.gov (United States)

    Wildfeuer, A; Heymer, B; Spilker, D; Schleifer, K H; Vanek, E; Haferkamp, O

    1975-07-01

    The gelation of a lysate prepared from the amebocytes of Limulus polyphemus, the horseshoe crab, has been used to detect endotoxin-like material in clinical studies and in "in vitro" experiments. The investigation of blood samples from 54 hospitalized patients suspected of having endotoxemia, revealed a positive limulus test in 14. Infections due to gram-positive organisms were not associated with positive assays. These results were in agreement with the observation that living gram-positive microorganisms - in contrast to gram-negative bacteria - did not initiate lysate gelation when studied "in vitro". Only very high concentrations of peptidoglycan, isolated from the cell walls of various gram-positive bacteria, induced the reaction. Therefore, these findings support the view, that the limulus test is relatively specific for the detection of gram-negative bacterial endotoxin and endotoxemia.

  19. Inactivation of Escherichia coli Endotoxin by Soft Hydrothermal Processing▿

    Science.gov (United States)

    Miyamoto, Toru; Okano, Shinya; Kasai, Noriyuki

    2009-01-01

    Bacterial endotoxins, also known as lipopolysaccharides, are a fever-producing by-product of gram-negative bacteria commonly known as pyrogens. It is essential to remove endotoxins from parenteral preparations since they have multiple injurious biological activities. Because of their strong heat resistance (e.g., requiring dry-heat sterilization at 250°C for 30 min) and the formation of various supramolecular aggregates, depyrogenation is more difficult than sterilization. We report here that soft hydrothermal processing, which has many advantages in safety and cost efficiency, is sufficient to assure complete depyrogenation by the inactivation of endotoxins. The endotoxin concentration in a sample was measured by using a chromogenic limulus method with an endotoxin-specific limulus reagent. The endotoxin concentration was calculated from a standard curve obtained using a serial dilution of a standard solution. We show that endotoxins were completely inactivated by soft hydrothermal processing at 130°C for 60 min or at 140°C for 30 min in the presence of a high steam saturation ratio or with a flow system. Moreover, it is easy to remove endotoxins from water by soft hydrothermal processing similarly at 130°C for 60 min or at 140°C for 30 min, without any requirement for ultrafiltration, nonselective adsorption with a hydrophobic adsorbent, or an anion exchanger. These findings indicate that soft hydrothermal processing, applied in the presence of a high steam saturation ratio or with a flow system, can inactivate endotoxins and may be useful for the depyrogenation of parenterals, including end products and medical devices that cannot be exposed to the high temperatures of dry heat treatments. PMID:19502435

  20. Modeling the LPS Neutralization Activity of Anti-Endotoxins

    Directory of Open Access Journals (Sweden)

    Virapong Prachayasittikul

    2009-05-01

    Full Text Available Bacterial lipopolysaccharides (LPS, also known as endotoxins, are major structural components of the outer membrane of Gram-negative bacteria that serve as a barrier and protective shield between them and their surrounding environment. LPS is considered to be a major virulence factor as it strongly stimulates the secretion of pro-inflammatory cytokines which mediate the host immune response and culminating in septic shock. Quantitative structure-activity relationship studies of the LPS neutralization activities of anti-endotoxins were performed using charge and quantum chemical descriptors. Artificial neural network implementing the back-propagation algorithm was selected for the multivariate analysis. The predicted activities from leave-one-out cross-validation were well correlated with the experimental values as observed from the correlation coefficient and root mean square error of 0.930 and 0.162, respectively. Similarly, the external testing set also yielded good predictivity with correlation coefficient and root mean square error of 0.983 and 0.130. The model holds great potential for the rational design of novel and robust compounds with enhanced neutralization activity.

  1. Relation of structure to function for the US reference standard endotoxin after exposure to 60Co radiation

    International Nuclear Information System (INIS)

    Csako, G.; Suba, E.A.; Ahlgren, A.; Tsai, C.M.; Elin, R.J.

    1986-01-01

    The structure and function of the highly purified US reference standard endotoxin (RSE) were studied after exposure to ionizing radiation from a 60 Co source. With increasing doses of radiation, the trilaminar ribbon-like structure of untreated endotoxin exhibited focal swelling, after which only spherical particles were seen by electron microscopy. These morphological changes were paralleled by the respective loss of O-side chain repeating units and pieces of the R-core from the lipopolysaccharide molecules, as demonstrated by electrophoresis. The biologic function of the irradiated endotoxin was assessed with a variety of tests. At higher doses of radiation, a direct relation was observed between the degradation of the molecular and supramolecular structure and the loss of biologic function. At lower doses of radiation, however, there was variability among the functional assays in their rate of change with progressive irradiation of the RSE. The results suggest that the carbohydrate moiety plays an important role both in determining the supramolecular structure and in modulating certain biologic activities of bacterial endotoxins

  2. Membrane adsorber for endotoxin removal

    Directory of Open Access Journals (Sweden)

    Karina Moita de Almeida

    Full Text Available ABSTRACT The surface of flat-sheet nylon membranes was modified using bisoxirane as the spacer and polyvinyl alcohol as the coating polymer. The amino acid histidine was explored as a ligand for endotoxins, aiming at its application for endotoxin removal from aqueous solutions. Characterization of the membrane adsorber, analysis of the depyrogenation procedures and the evaluation of endotoxin removal efficiency in static mode are discussed. Ligand density of the membranes was around 7 mg/g dry membrane, allowing removal of up to 65% of the endotoxins. The performance of the membrane adsorber prepared using nylon coated with polyvinyl alcohol and containing histidine as the ligand proved superior to other membrane adsorbers reported in the literature. The lack of endotoxin adsorption on nylon membranes without histidine confirmed that endotoxin removal was due to the presence of the ligand at the membrane surface. Modified membranes were highly stable, exhibiting a lifespan of approximately thirty months.

  3. Intestinal Endotoxins as Co-Factors of Liver Injury in Obstructive Jaundice

    OpenAIRE

    Menteş, B. Bülent; Tatlicioğlu, Ertan; Akyol, Gülen; Uluoğlu, Ömer; Sultan, Nedim; Yilmaz, Erdal; Çelebi, Murat; Taneri, Ferit; Ferahköşe, Zafer

    1996-01-01

    The concept of endotoxin-mediated rather than direct liver injury in biliary obsruction was investigated using the experimental rat model of bile duct ligation (BDL) and small bowel bacterial overgrowth (SBBO). Small identical doses of intravenous endotoxin (bacterial LPS) caused a significantly more severe liver injury in rats with BDL, compared with sham-operated rats, suggesting the possible contribution of LPS in this type of liver damage. BDL was then combined with surgica...

  4. [The importance of endotoxin producing bacterias for practical purposes

    Science.gov (United States)

    Schimmel, Dietrich

    1994-01-01

    Lipopolysaccharides (endotoxin) cause according to resorption out of the intestinal tract or aerogenic inhalation or by a septic infection clinical signs. The clinical reactions are praeshock symptoms, acute forms of shock and death. The experimental intratracheally administration of lipopolysaccharides into calves caused pneumonic lesions without bacterial experimental infection.

  5. Immunostimulatory capacity of dental casting alloys on endotoxin responsiveness.

    Science.gov (United States)

    Rachmawati, Dessy; von Blomberg, B Mary E; Kleverlaan, Cornelis J; Scheper, Rik J; van Hoogstraten, Ingrid M W

    2017-05-01

    Oral metal exposure has been associated with systemic and local adverse reactions, probably due to elemental release from the alloys. Although supraphysiological concentrations of salts from dentally applied metals can activate innate cells through TLR4 (Ni, Co, Pd) and TLR3 (Au), whether direct exposure to solid alloys can also trigger innate immune reactivity is still unknown. The purpose of this in vitro study was to determine whether dental cast alloy specimens can activate innate cells and influence their responsiveness to bacterial endotoxin. Human monocyte-derived dendritic cells (MoDC) and THP-1 cells were cultured on top of different alloy specimens (Ni-Cr, Co-Cr, Pd-Cu, Pd-Ag, Ti-6Al-4V, amalgam, gold, and stainless steel) or in alloy-exposed culture medium with or without endotoxin (lipopolysaccharide [LPS]; Escherichia coli 055:B5). Interleukin-8 (IL-8) production was used as the parameter for innate stimulation and evaluated by enzyme-linked immunosorbent assay after 24 hours of culture. The statistical significance of the effects of various casting alloys on the secretion of IL-8 was analyzed by using the nonparametric Wilcoxon rank sum test (α=.05). Dental cast alloys induced IL-8 production in MoDC and THP-1 cells, with Au and Pd-Cu providing the strongest stimulation. The alloy-exposed culture media tested contained sufficient stimulatory metal ions to induce detectable IL-8 production in THP-1 cells, except for the Ni-Cr and stainless steel exposed media. Au and Pd-Cu alloys were also most effective in potentiating LPS responsiveness as measured by IL-8 production. Using an in vitro culture system to expose MoDC and THP-1 cells to different alloy specimens this study showed that contact with the solid alloys, in particular when they contain Pd or Au, can trigger innate immune responses and augment responsiveness to bacterial endotoxin. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All

  6. The effectiveness of various biofiltration substrates in removing bacteria, endotoxins, and dust from ventilation system exhaust from a chicken hatchery.

    Science.gov (United States)

    Tymczyna, L; Chmielowiec-Korzeniowska, A; Drabik, A

    2007-10-01

    The objective of this study was to evaluate the effectiveness of various organic and organic-mineral biofilter media in purifying ventilation exhaust from a chicken hatchery room. Three different substrates were tested. Efficiency levels for the removal of dust, gram-negative bacteria, and bacterial endotoxin were recorded. The microbiological properties of the substrates were also studied. All of the biofilter substrates were highly effective in removing gram-negative bacteria, moderately effective in reducing dust levels, and only slightly effective in removing endotoxin. The substrate that was most efficient in retaining bioaerosols was the organic-mineral medium containing 20% halloysite, 40% compost, and 40% peat, which generally had at least satisfactory efficiency values for removing all of the contaminants tested.

  7. Detoxifying Escherichia coli for endotoxin-free production of recombinant proteins.

    Science.gov (United States)

    Mamat, Uwe; Wilke, Kathleen; Bramhill, David; Schromm, Andra Beate; Lindner, Buko; Kohl, Thomas Andreas; Corchero, José Luis; Villaverde, Antonio; Schaffer, Lana; Head, Steven Robert; Souvignier, Chad; Meredith, Timothy Charles; Woodard, Ronald Wesley

    2015-04-16

    Lipopolysaccharide (LPS), also referred to as endotoxin, is the major constituent of the outer leaflet of the outer membrane of virtually all Gram-negative bacteria. The lipid A moiety, which anchors the LPS molecule to the outer membrane, acts as a potent agonist for Toll-like receptor 4/myeloid differentiation factor 2-mediated pro-inflammatory activity in mammals and, thus, represents the endotoxic principle of LPS. Recombinant proteins, commonly manufactured in Escherichia coli, are generally contaminated with endotoxin. Removal of bacterial endotoxin from recombinant therapeutic proteins is a challenging and expensive process that has been necessary to ensure the safety of the final product. As an alternative strategy for common endotoxin removal methods, we have developed a series of E. coli strains that are able to grow and express recombinant proteins with the endotoxin precursor lipid IVA as the only LPS-related molecule in their outer membranes. Lipid IVA does not trigger an endotoxic response in humans typical of bacterial LPS chemotypes. Hence the engineered cells themselves, and the purified proteins expressed within these cells display extremely low endotoxin levels. This paper describes the preparation and characterization of endotoxin-free E. coli strains, and demonstrates the direct production of recombinant proteins with negligible endotoxin contamination.

  8. Genetic engineering approach to develop next-generation reagents for endotoxin quantification

    Science.gov (United States)

    Ogura, Norihiko; Aketagawa, Jun; Aizawa, Maki; Kobayashi, Yuki; Kawabata, Shun-ichiro; Oda, Toshio

    2016-01-01

    The bacterial endotoxin test, which uses amebocyte lysate reagents of horseshoe crab origin, is a sensitive, reproducible and simple assay to measure endotoxin concentration. To develop sustainable raw materials for lysate reagents that do not require horseshoe crabs, three recombinant protease zymogens (factor C, derived from mammalian cells; factor B; and the proclotting enzyme derived from insect cells) were prepared using a genetic engineering technique. Recombinant cascade reagents (RCRs) were then prepared to reconstruct the reaction cascade in the amebocyte lysate reagent. The protease activity of the RCR containing recombinant factor C was much greater than that of recombinant factor C alone, indicating the efficiency of signal amplification in the cascade. Compared with the RCR containing the insect cell-derived factor C, those containing mammalian cell-derived factor C, which features different glycosylation patterns, were less susceptible to interference by the injectable drug components. The standard curve of the RCR containing mammalian cell-derived recombinant factor C had a steeper slope than the curves for those containing natural lysate reagents, suggesting a greater sensitivity to endotoxin. The present study supports the future production of recombinant reagents that do not require the use of natural resources. PMID:27913792

  9. Genetic engineering approach to develop next-generation reagents for endotoxin quantification.

    Science.gov (United States)

    Mizumura, Hikaru; Ogura, Norihiko; Aketagawa, Jun; Aizawa, Maki; Kobayashi, Yuki; Kawabata, Shun-Ichiro; Oda, Toshio

    2017-02-01

    The bacterial endotoxin test, which uses amebocyte lysate reagents of horseshoe crab origin, is a sensitive, reproducible and simple assay to measure endotoxin concentration. To develop sustainable raw materials for lysate reagents that do not require horseshoe crabs, three recombinant protease zymogens (factor C, derived from mammalian cells; factor B; and the proclotting enzyme derived from insect cells) were prepared using a genetic engineering technique. Recombinant cascade reagents (RCRs) were then prepared to reconstruct the reaction cascade in the amebocyte lysate reagent. The protease activity of the RCR containing recombinant factor C was much greater than that of recombinant factor C alone, indicating the efficiency of signal amplification in the cascade. Compared with the RCR containing the insect cell-derived factor C, those containing mammalian cell-derived factor C, which features different glycosylation patterns, were less susceptible to interference by the injectable drug components. The standard curve of the RCR containing mammalian cell-derived recombinant factor C had a steeper slope than the curves for those containing natural lysate reagents, suggesting a greater sensitivity to endotoxin. The present study supports the future production of recombinant reagents that do not require the use of natural resources.

  10. Determinants of house dust, endotoxin, and β-(1→3)-D-glucan in homes of Danish children

    NARCIS (Netherlands)

    Holst, G; Høst, A; Doekes, G; Meyer, H W; Madsen, A M; Sigsgaard, T

    Little is known about the geographic variation and determinants of bacterial endotoxin and β-(1,3)-D-glucan in Danish house dust. In a population of 317 children, we: (i) described loads and concentrations of floor dust, endotoxin, and β-(1→3)-D-glucan and (ii) their correlations and (iii) assessed

  11. Diet Matters: Endotoxin in the Diet Impacts the Level of Allergic Sensitization in Germ-Free Mice.

    Directory of Open Access Journals (Sweden)

    Martin Schwarzer

    Full Text Available Germ-free animals have been used to define the vital role of commensal bacteria on the maturation of the host immune system. However, the role of bacterial residues in diet in this setting is poorly understood. Here we investigated the effect of bacterial contamination in sterile diet on the level of allergic sensitization in germ-free mice. Sterile grain-based diets ST1 and R03 were tested for the level of bacterial contamination. ST1 contained higher amount of bacterial DNA, approximately ten times more endotoxin, and induced higher, TLR4-dependent, cytokine production in dendritic cells compared to R03. In a germ-free mouse model of sensitization to the major birch pollen allergen Bet v 1, feeding on ST1 for at least two generations was associated with decreased production of allergen-specific IgE and IgG1 antibodies in sera in comparison to R03. Furthermore, reduced levels of allergen-specific and ConA-induced cytokines IL-4, IL-5 and IL-13 accompanied by increased levels of IFN-γ were detected in splenocytes cultures of these mice. Our results show that contamination of experimental diet with bacterial residues, such as endotoxin, significantly affects the development of allergic sensitization in germ-free mice. Therefore, careful selection of sterile food is critical for the outcomes of germ-free or gnotobiotic experimental models of immune-deviated diseases.

  12. Endotoxins in surgical instruments of hip arthroplasty

    OpenAIRE

    Goveia, Vania Regina; Mendoza, Isabel Yovana Quispe; Guimarães, Gilberto Lima; Ercole, Flavia Falci; Couto, Bráulio Roberto Gonçalves Marinho; Leite, Edna Marilea Meireles; Stoianoff, Maria Aparecida Resende; Ferreira, José Antonio Guimarães

    2016-01-01

    Abstract OBJECTIVE To investigate endotoxins in sterilized surgical instruments used in hip arthroplasties. METHOD A descriptive exploratory study conducted in a public teaching hospital. Six types of surgical instruments were selected, namely: acetabulum rasp, femoral rasp, femoral head remover, chisel box, flexible bone reamer and femoral head test. The selection was based on the analysis of the difficulty in removing bone and blood residues during cleaning. The sample was made up of 60...

  13. Tissue protein nitration and peripheral blood endotoxin activity are indicative of the severity of systemic organ compromise in naturally-occurring clinical cases of bacterial mastitis in Holstein dairy cows

    Science.gov (United States)

    The objective of this survey study was to determine a relationship between the intensity of tissue protein tyrosine nitration measured in samples of mammary gland, liver, pancreas and lung compared to estimated blood endotoxin (LPS) activity. Blood was collected from nine multiparous Holstein cows...

  14. Microfiltration, Nano-filtration and Reverse Osmosis for the Removal of Toxins (LPS Endotoxins) from Wastewater

    OpenAIRE

    Mokhtar, Guizani; Naoyuki, Funamizu

    2012-01-01

    Lipopolysaccharide (LPS) endotoxin, a bacterial byproduct abundantly present in wastewater, is more and more representing a major concern in wastewater treatment sector for the potential health risk it represents. It is, therefore, more urgent than before to protect consumers from contaminating their fresh potable water reserves with LPS endotoxin through aquifer replenishment using reclaimed wastewater or by supplying reclaimed wastewater as potable water. Membrane treatment is an alternativ...

  15. Evaluation of the Limulus amoebocyte lysate test in conjunction with a gram negative bacterial plate count for detecting irradiation of chicken

    International Nuclear Information System (INIS)

    Scotter, S.L.; Wood, R.; McWeeny, D.J.

    1990-01-01

    A study to evaluate the potential of the Limulus amoebocyte lysate (LAL) test in conjunction with a Gram negative bacterial (GNB) plate count for detecting the irradiation of chicken is described. Preliminary studies demonstrated that chickens irradiated at an absorbed dose of 2.5 kGy could be differentiated from unirradiated birds by measuring levels of endotoxin and of numbers of GNB on chicken skin. Irradiated birds were found to have endotoxin levels similar to those found in unirradiated birds but significantly lower numbers of GNB. In a limited study the test was found to be applicable to birds from different processors. The effect of temperature abuse on the microbiological profile, and thus the efficacy of the test, was also investigated. After temperature abuse, the irradiated birds were identifiable at worst up to 3 days after irradiation treatment at the 2.5 kGy level and at best some 13 days after irradiation. Temperature abuse at 15 0 C resulted in rapid recovery of surviving micro-organisms which made differentiation of irradiated and unirradiated birds using this test unreliable. The microbiological quality of the bird prior to irradiation treatment also affected the test as large numbers of GNB present on the bird prior to irradiation treatment resulted in larger numbers of survivors. In addition, monitoring the developing flora after irradiation treatment amd during subsequent chilled storage also aided differentiation of irradiated and unirradiated birds. Large numbers of yeast and Gram positive cocci were isolated from irradiated carcasses whereas Gram negative oxidative rods were the predominant spoilage flora on unirradiated birds. (author)

  16. Evaluation of the Limulus amoebocyte lysate test in conjunction with a gram negative bacterial plate count for detecting irradiation of chicken

    Energy Technology Data Exchange (ETDEWEB)

    Scotter, S.L.; Wood, R.; McWeeny, D.J. (Ministry of Agriculture, Fisheries and Food, Norwich (UK). Food Science Lab.)

    1990-01-01

    A study to evaluate the potential of the Limulus amoebocyte lysate (LAL) test in conjunction with a Gram negative bacterial (GNB) plate count for detecting the irradiation of chicken is described. Preliminary studies demonstrated that chickens irradiated at an absorbed dose of 2.5 kGy could be differentiated from unirradiated birds by measuring levels of endotoxin and of numbers of GNB on chicken skin. Irradiated birds were found to have endotoxin levels similar to those found in unirradiated birds but significantly lower numbers of GNB. In a limited study the test was found to be applicable to birds from different processors. The effect of temperature abuse on the microbiological profile, and thus the efficacy of the test, was also investigated. After temperature abuse, the irradiated birds were identifiable at worst up to 3 days after irradiation treatment at the 2.5 kGy level and at best some 13 days after irradiation. Temperature abuse at 15{sup 0}C resulted in rapid recovery of surviving micro-organisms which made differentiation of irradiated and unirradiated birds using this test unreliable. The microbiological quality of the bird prior to irradiation treatment also affected the test as large numbers of GNB present on the bird prior to irradiation treatment resulted in larger numbers of survivors. In addition, monitoring the developing flora after irradiation treatment amd during subsequent chilled storage also aided differentiation of irradiated and unirradiated birds. Large numbers of yeast and Gram positive cocci were isolated from irradiated carcasses whereas Gram negative oxidative rods were the predominant spoilage flora on unirradiated birds. (author).

  17. Detection and quantitative evaluation of endotoxin contamination in nanoparticle formulations by LAL-based assays.

    Science.gov (United States)

    Neun, Barry W; Dobrovolskaia, Marina A

    2011-01-01

    Bacterial endotoxin or lipopolysaccharide (LPS) is a membrane component of all Gram-negative bacteria. The administration of products contaminated with bacterial endotoxin can cause fever, shock, and even death. Accordingly, the FDA sets limits on the number of endotoxin units (EU) that may be present in a drug or device product. Limulus amoebocyte lysate (LAL) is the extract from amoebocytes of the horseshoe crab Limulus polyphemus, which reacts with bacterial endotoxin. Detection of the products of this reaction is an effective means of quantifying the EU present in a drug formulation. However, nanoparticles frequently interfere with the reactivity of endotoxin, the LAL reaction, or the detection of the reaction products. This interference can be manifested as either an enhancement or an inhibition, causing a respective overestimation or underestimation of the EU in the sample. Here, we present two methods for the detection and quantification of endotoxin in nanoparticle preparations: one is based on an end-point chromogenic LAL assay, and the second approach is based on measuring the turbidity of the LAL extract.

  18. Bacterial and enzymatic bioassays for toxicity testing in the environment.

    Science.gov (United States)

    Bitton, G; Koopman, B

    1992-01-01

    Microbioassays using bacteria or enzymes are increasingly applied to measure chemical toxicity in the environment. Attractive features of these assays may include low cost, rapid response to toxicants, high sample throughput, modest laboratory equipment and space requirements, low sample volume, portability, and reproducible responses. Enzymatic tests rely on measurement of either enzyme activity or enzyme biosynthesis. Dehydrogenases are the enzymes most used in toxicity testing. Assay of dehydrogenase activity is conveniently carried out using oxidoreduction dyes such as tetrazolium salts. Other enzyme activity tests utilize ATPases, esterases, phosphatases, urease, luciferase, beta-galactosidase, protease, amylase, or beta-glucosidase. Recently, the inhibition of enzyme (beta-galactosidase, tryptophanase, alpha-glucosidase) biosynthesis has been explored as a basis for toxicity testing. Enzyme biosynthesis was found to be generally more sensitive to organic chemicals than enzyme activity. Bacterial toxicity tests are based on bioluminescence, motility, growth, viability, ATP, oxygen uptake, nitrification, or heat production. An important aspect of bacterial tests is the permeability of cells to environmental toxicants, particularly organic chemicals of hydrophobic nature. Physical, chemical, and genetic alterations of the outer membrane of E. coli have been found to affect test sensitivity to organic toxicants. Several microbioassays are now commercially available. The names of the assays and their basis are: Microtox (bioluminescence), Polytox (respiration), ECHA Biocide Monitor (dehydrogenase activity), Toxi-Chromotest (enzyme biosynthesis), and MetPAD (enzyme activity). An important feature common to these tests is the provision of standardized cultures of bacteria in freeze-dried form. Two of the more recent applications of microbioassays are in sediment toxicity testing and toxicity reduction evaluation. Sediment pore water may be assayed directly or

  19. Rapid microbiological testing: monitoring the development of bacterial stress.

    Directory of Open Access Journals (Sweden)

    Boris Zavizion

    2010-10-01

    Full Text Available The ability to respond to adverse environments effectively along with the ability to reproduce are sine qua non conditions for all sustainable cellular forms of life. Given the availability of an appropriate sensing modality, the ubiquity and immediacy of the stress response could form the basis for a new approach for rapid biological testing. We have found that measuring the dielectric permittivity of a cellular suspension, an easily measurable electronic property, is an effective way to monitor the response of bacterial cells to adverse conditions continuously. The dielectric permittivity of susceptible and resistant strains of Escherichia coli and Staphylococcus aureus, treated with gentamicin and vancomycin, were measured directly using differential impedance sensing methods and expressed as the Normalized Impedance Response (NIR. These same strains were also heat-shocked and chemically stressed with Triton X-100 or H(2O(2. The NIR profiles obtained for antibiotic-treated susceptible organisms showed a strong and continuous decrease in value. In addition, the intensity of the NIR value decrease for susceptible cells varied in proportion to the amount of antibiotic added. Qualitatively similar profiles were found for the chemically treated and heat-shocked bacteria. In contrast, antibiotic-resistant cells showed no change in the NIR values in the presence of the drug to which it is resistant. The data presented here show that changes in the dielectric permittivity of a cell suspension are directly correlated with the development of a stress response as well as bacterial recovery from stressful conditions. The availability of a practical sensing modality capable of monitoring changes in the dielectric properties of stressed cells could have wide applications in areas ranging from the detection of bacterial infections in clinical specimens to antibiotic susceptibility testing and drug discovery.

  20. Experiments on prevention of the endotoxin-abortifacient effect by radiodetoxified endotoxin pretreatment in rats

    Energy Technology Data Exchange (ETDEWEB)

    Csordas, T.; Bertok, L.; Csapo, Z.

    1978-01-01

    Endotoxemia has been induced in pregnant rats by intravenous injection of 1 mg Escherichia coli endotoxin which resulted in intrauterine death and abortion of fetuses in 24 h. The abortifacient effect of endotoxin, injected intravenously 24 h earlier. The authors suppose that the radiodetoxified endotoxin can be a good tool also in the prevention of human septic (endotoxin) shock in pregnancy.

  1. Test for bacterial resistance build-up against plasma treatment

    International Nuclear Information System (INIS)

    Zimmermann, J L; Shimizu, T; Li, Y-F; Morfill, G E; Schmidt, H-U; Isbary, G

    2012-01-01

    It is well known that the evolution of resistance of microorganisms to a range of different antibiotics presents a major problem in the control of infectious diseases. Accordingly, new bactericidal ‘agents’ are in great demand. Using a cold atmospheric pressure (CAP) plasma dispenser operated with ambient air, a more than five orders of magnitude inactivation or reduction of Methicillin-resistant Staphylococcus aureus (MRSA; resistant against a large number of the tested antibiotics) was obtained in less than 10 s. This makes CAP the most promising candidate for combating nosocomial (hospital-induced) infections. To test for the occurrence and development of bacterial resistance against such plasmas, experiments with Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Enterococcus mundtii) were performed. The aim was to determine quantitative limits for primary (naturally) or secondary (acquired) resistance against the plasma treatment. Our results show that E. coli and E. mundtii possess no primary resistance against the plasma treatment. By generating four generations of bacteria for every strain, where the survivors of the plasma treatment were used for the production of the next generation, a lower limit to secondary resistance was obtained. Our results indicate that CAP technology could contribute to the control of infections in hospitals, in outpatient care and in disaster situations, providing a new, fast and efficient broad-band disinfection technology that is not constrained by bacterial resistance mechanisms. (paper)

  2. Faecal Endotoxin in Human Volunteers: Normal Values

    OpenAIRE

    Van Saene, J. J. M.; Stoutenbeek, C. P.; Van Saene, H. K. F.

    2011-01-01

    This paper presents a study measuring endotoxin levels in faeces of healthy adults using the Limulus amoebocyte lysate (LAL) microassay. Data showed mean faecal endotoxin levels of 1 mg (range 0.01-100 mg) per gram of faeces. No correlation was found with the concentration of Enterobacteriaceae in faeces and free Faecal endotoxin levels.Keywords: Endotoxin; LAL micro-assay; LPS; Faeccs; Human volunteers: Enterobacteriaceae.

  3. Endotoxin: From database to measurement strategy

    NARCIS (Netherlands)

    Spaan, S.; Schinkel, J.M.; Wouters, I.M.; Preller, E.A.; Tjoe Nij, E.I.M.; Heederik, D.; Tielemans, E.L.J.P.; Preller, L.

    2007-01-01

    Endotoxin is a well-known toxin which has been associated with several health effects. Many factors influence airborne endotoxin exposure and can cause high variability in exposure between and within workers. Additionally, since the source of endotoxin exposure - gram-negative bacteria - grow and

  4. Assay of endotoxin by limulus amebocyte lysate.

    Science.gov (United States)

    Ketchum, P A; Novitsky, T J

    2000-01-01

    Horseshoe crabs fight off infectious agents with a complex array of proteins present in amebocytes, the major cell type in their hemolymph. These amebocytes contain both large and small granules (1). When exposed to bacteria or other infectious agents the amebocytes release proteins into their surroundings by exocytosis. The small granules of Limulus amebocytes contain antibacterial proteins, including polyphemusins and the big defensins (2). The large granules contain the Limulus anti-lipopolysaccharide factor (LALF) and the clot-forming group of serine protease zymogens. Exocytosis is initiated by the reaction of amebocytes with lipopolysaccharide (LPS) from Gram-negative bacteria or other microbial components. LPS is also called endotoxin because it is found in the outer membrane of the gram-negative bacterial cell wall. A solid clot forms in response to the lipid A portion of LPS, thereby walling off the infection site or preventing the loss of blood when the animal is damaged physically (3).

  5. Diagnostic and prognostic significance of plasma endotoxin determination in febrile patients with haematological malignancies.

    Science.gov (United States)

    Yoshida, M; Obayashi, T; Tamura, H; Tanaka, S; Kawai, T; Sakamoto, S; Miura, Y

    1994-01-01

    We evaluated the clinical utility of a new endotoxin-specific chromogenic limulus test in febrile patients with haematological malignancies. The specificity is assured by the removal of factor G, which is sensitive to (1-->3)-beta-D-glucan, from horseshoe crab amoebocyte lysate. The sensitivity and specificity of the test to systemic gram-negative bacterial infections were 69.7 and 96.3%, respectively. Meanwhile, gram-negative bacteria grew in only 39.7% of endotoxaemic samples. Thus, it seems appropriate to consider gram-negative bacteraemia and endotoxaemia as different entities. Endotoxaemia was significantly associated with septic shock and infectious death, especially in patients with neutropenia. The new test, the results of which are available within 3 h, should help physicians to recognise this ominous sign early and to initiate a prompt countermeasure to endotoxaemia.

  6. Quantification of cultivable bacteria and endotoxin in post-treatment apical periodontitis before and after chemo-mechanical preparation.

    Science.gov (United States)

    Endo, M S; Martinho, F C; Zaia, A A; Ferraz, C C R; Almeida, J F A; Gomes, B P F A

    2012-10-01

    This clinical study was conducted to quantify cultivable bacteria and endotoxin in root canals with post-treatment apical periodontitis by correlating their levels with clinical features and to evaluate the effect of chemo-mechanical preparation (CMP) with 2 % chlorhexidine gel + 17 % EDTA on bacterial and endotoxin removal/elimination. Moreover, target strict Gram-negative anaerobic bacteria were investigated by polymerase chain reaction (PCR). Fifteen teeth with post-treatment apical periodontitis were sampled before (s1) and after (s2) CMP. Culture techniques determined the number of colony-forming units (CFU). PCR (16S rDNA) and limulus amebocyte lysate (LAL) assay were used for bacterial and endotoxin detection, respectively. Prevotella nigrescens (4/15), Prevotella intermedia (2/15), and Tannerella forsythia (2/15) were the most frequently detected species. Endotoxin was recovered in 100 % of the samples. At s1, bacteria and endotoxin were detected at a median value of 5.14 × 10(3) CFU/mL and 3.96 EU/mL, respectively. Higher levels of endotoxin were related to a larger size of radiolucent area (>5 mm) (p area in the periapical region. Moreover, CMP was effective in reducing both bacterial and endotoxin contents in post-treatment apical periodontitis.

  7. Research on securing no bacteria and nonfeverish property for disposable medical appliances. Inactivation of endotoxin by Co-60 γ ray

    International Nuclear Information System (INIS)

    Hosobuchi, Kazunari; Tanamoto, Kenichi; Haijima, Yuji.

    1996-01-01

    The contamination by fever-causing endotoxin has become a large problem in medical treatment field. In the industry manufacturing disposable medical appliances, the method of manufacturing endotoxin-free products is an important subject, and the development of the methods of inactivating and eliminating efficiently endotoxin is desired. As a part of this development, the possibility of inactivating endotoxin with Co-60 γ ray was examined. The sample was the endotoxin originated from E.Coli R3 F653 strain. For the irradiation, the Co-60 γ ray irradiation apparatus of 185 T-Bq in National Institute of Hygienic Sciences was used. The measurement of the activity of endotoxin was carried out by limulus test synthetic substrate method. The activity value of the endotoxin in aqueous solution decreased logarithmically with the increasing irradiation dose, and this decreasing tendency was not affected by the initial concentration of the endotoxin. The experiment of recovering freezing-dried endotoxin from a vial is described. The results of inactivating the endotoxin in dry system by γ ray are reported. (K.I.)

  8. Single session of Nd:YAG laser intracanal irradiation neutralizes endotoxin in dental root dentin

    Science.gov (United States)

    Archilla, José R. F.; Moreira, Maria S. N. A.; Miyagi, Sueli P. H.; Bombana, Antônio C.; Gutknecht, Norbert; Marques, Márcia M.

    2012-11-01

    Endotoxins released in the dental root by Gram-negative microorganisms can be neutralized by calcium hydroxide, when this medication is applied inside the root canal for at least seven days. However, several clinical situations demand faster root canal decontamination. Thus, for faster endotoxin neutralization, endodontists are seeking additional treatments. The in vitro study tested whether or not intracanal Nd:YAG laser irradiation would be able to neutralize endotoxin within the human dental root canal in a single session. Twenty-four human teeth with one root were mounted between two chambers. After conventional endodontic treatment, root canals were contaminated with Escherichia coli endotoxin. Then they were irradiated or not (controls) in contact mode with an Nd:YAG laser (1.5 W, 15 Hz, 100 mJ and pulse fluency of 124 J/cm2). The endotoxin activity was measured using the limulus lysate technique and data were statistically compared (p≤0.05). The concentration of active endotoxin measured in the negative control group was significantly lower than that of the positive control group (p=0.04). The concentrations of endotoxin in both irradiated groups were significantly lower than that of the positive control group (p=0.027) and similar to that of negative control group (p=0.20). A single session of intracanal Nd:YAG laser irradiation is able to neutralize endotoxin in the dental root tissues.

  9. Single session of Nd:YAG laser intracanal irradiation neutralizes endotoxin in dental root dentin.

    Science.gov (United States)

    Archilla, José R F; Moreira, Maria S N A; Miyagi, Sueli P H; Bombana, Antônio C; Gutknecht, Norbert; Marques, Márcia M

    2012-11-01

    Endotoxins released in the dental root by Gram-negative microorganisms can be neutralized by calcium hydroxide, when this medication is applied inside the root canal for at least seven days. However, several clinical situations demand faster root canal decontamination. Thus, for faster endotoxin neutralization, endodontists are seeking additional treatments. The in vitro study tested whether or not intracanal Nd:YAG laser irradiation would be able to neutralize endotoxin within the human dental root canal in a single session. Twenty-four human teeth with one root were mounted between two chambers. After conventional endodontic treatment, root canals were contaminated with Escherichia coli endotoxin. Then they were irradiated or not (controls) in contact mode with an Nd:YAG laser (1.5 W, 15 Hz, 100 mJ and pulse fluency of 124  J/cm2). The endotoxin activity was measured using the limulus lysate technique and data were statistically compared (p≤0.05). The concentration of active endotoxin measured in the negative control group was significantly lower than that of the positive control group (p=0.04). The concentrations of endotoxin in both irradiated groups were significantly lower than that of the positive control group (p=0.027) and similar to that of negative control group (p=0.20). A single session of intracanal Nd:YAG laser irradiation is able to neutralize endotoxin in the dental root tissues.

  10. Biophysical Analysis of Lipopolysaccharide Formulations for an Understanding of the Low Endotoxin Recovery (LER Phenomenon

    Directory of Open Access Journals (Sweden)

    Wilmar Correa

    2017-12-01

    Full Text Available Lipopolysaccharides (LPS, endotoxin are complex and indispensable components of the outer membrane of most Gram-negative bacteria. They represent stimuli for many biological effects with pathophysiological character. Recombinant therapeutic proteins that are manufactured using biotechnological processes are prone to LPS contaminations due to their ubiquitous occurrence. The maximum endotoxin load of recombinant therapeutic proteins must be below the pyrogenic threshold. Certain matrices that are commonly used for recombinant therapeutic proteins show a phenomenon called “Low Endotoxin Recovery (LER”. LER is defined as the loss of detectable endotoxin activity over time using compendial Limulus amebocyte lysate (LAL assays when undiluted products are spiked with known amount of endotoxin standards. Because LER poses potential risks that endotoxin contaminations in products may be underestimated or undetected by the LAL assay, the United States (U.S. Food and Drug Administration’s (FDA’s Center for Drug Evaluation and Research (CDER has recently started requesting that companies conduct endotoxin spike/hold recovery studies to determine whether a given biological product causes LER. Here, we have performed an analysis of different LPS preparations with relevant detergents studying their acyl chain phase transition, their aggregate structures, their size distributions, and binding affinity with a particular anti-endotoxin peptide, and correlating it with the respective data in the macrophage activation test. In this way, we have worked out biophysical parameters that are important for an understanding of LER.

  11. Bacterial cellulose skin masks-Properties and sensory tests.

    Science.gov (United States)

    Pacheco, Guilherme; de Mello, Carolina Véspoli; Chiari-Andréo, Bruna Galdorfini; Isaac, Vera Lucia Borges; Ribeiro, Sidney José Lima; Pecoraro, Édison; Trovatti, Eliane

    2017-09-29

    Bacterial cellulose (BC) is a versatile material produced by microorganisms in the form of a membranous hydrogel, totally biocompatible, and endowed with high mechanical strength. Its high water-holding capacity based on its highly porous nanofibrillar structure allows BC to incorporate and to release substances very fast, thus being suitable for the preparation of skincare masks. The preparation and characterization of cosmetic masks based on BC membranes and active cosmetics. The masks were prepared by the simple incorporation of the cosmetic actives into BC membranes, used as a swelling matrix. The masks were characterized by Fourier transform infrared (FTIR), scanning electron microscopy (SEM), sensory tests, and skin moisture tests on volunteers. The results of sensory tests revealed the good performance of BC, being considered effective by the panel of volunteers, specially for adhesion to the skin (7.7 at the score scale), and improvement of the skin moisture (the hydration effect increased 76% in 75% of the volunteers that used vegetable extract mask formulation [VEM]), or a decrease in skin hydration (80% of the volunteers showed 32.6% decrease on skin hydration using propolis extract formulation [PEM] treatment), indicating the BC nanofiber membranes can be used to skincare applications. The results demonstrate the BC can be used as an alternative support for cosmetic actives for skin treatment. © 2017 Wiley Periodicals, Inc.

  12. Leakage of Microbial Endotoxin through the Implant-Abutment Interface in Oral Implants: An In Vitro Study.

    Science.gov (United States)

    Garrana, Rhoodie; Mohangi, Govindrau; Malo, Paulo; Nobre, Miguel

    2016-01-01

    Background . Endotoxin initiates osteoclastic activity resulting in bone loss. Endotoxin leakage through implant abutment connections negatively influences peri-implant bone levels. Objectives . (i) To determine if endotoxin can traverse different implant-abutment connection (IAC) designs; (ii) to quantify the amount of endotoxins traversing the IAC; (iii) to compare the in vitro comportments of different IACs. Materials and Methods . Twenty-seven IACs were inoculated with E. coli endotoxin. Six of the twenty-seven IACs were external connections from one system (Southern Implants) and the remaining twenty-one IACs were made up of seven internal IAC types from four different implant companies (Straumann, Ankylos, and Neodent, Southern Implants). Results . Of the 27 IACs tested, all 6 external IACs leaked measurable amounts of endotoxin. Of the remaining 21 internal IACs, 9 IACs did not show measurable leakage whilst the remaining 12 IACs leaked varying amounts. The mean log endotoxin level was significantly higher for the external compared to internal types ( p = 0.015). Conclusion . Within the parameters of this study, we can conclude that endotoxin leakage is dependent on the design of the IAC. Straumann Synocta, Straumann Cross-fit, and Ankylos displayed the best performances of all IACs tested with undetectable leakage after 7 days. Each of these IACs incorporated a morse-like component in their design. Speculation still exists over the impact of IAC endotoxin leakage on peri-implant tissues in vivo; hence, further investigations are required to further explore this.

  13. Leakage of Microbial Endotoxin through the Implant-Abutment Interface in Oral Implants: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    Rhoodie Garrana

    2016-01-01

    Full Text Available Background. Endotoxin initiates osteoclastic activity resulting in bone loss. Endotoxin leakage through implant abutment connections negatively influences peri-implant bone levels. Objectives. (i To determine if endotoxin can traverse different implant-abutment connection (IAC designs; (ii to quantify the amount of endotoxins traversing the IAC; (iii to compare the in vitro comportments of different IACs. Materials and Methods. Twenty-seven IACs were inoculated with E. coli endotoxin. Six of the twenty-seven IACs were external connections from one system (Southern Implants and the remaining twenty-one IACs were made up of seven internal IAC types from four different implant companies (Straumann, Ankylos, and Neodent, Southern Implants. Results. Of the 27 IACs tested, all 6 external IACs leaked measurable amounts of endotoxin. Of the remaining 21 internal IACs, 9 IACs did not show measurable leakage whilst the remaining 12 IACs leaked varying amounts. The mean log endotoxin level was significantly higher for the external compared to internal types (p=0.015. Conclusion. Within the parameters of this study, we can conclude that endotoxin leakage is dependent on the design of the IAC. Straumann Synocta, Straumann Cross-fit, and Ankylos displayed the best performances of all IACs tested with undetectable leakage after 7 days. Each of these IACs incorporated a morse-like component in their design. Speculation still exists over the impact of IAC endotoxin leakage on peri-implant tissues in vivo; hence, further investigations are required to further explore this.

  14. Mutagenicity of Flavonoids Assayed by Bacterial Reverse Mutation (Ames Test

    Directory of Open Access Journals (Sweden)

    Eliana Aparecida Varanda

    2012-05-01

    Full Text Available The mutagenicity of ten flavonoids was assayed by the Ames test, in Salmonella typhimurium strains TA98, TA100 and TA102, with the aim of establishing hydroxylation pattern-mutagenicity relationship profiles. The compounds assessed were: quercetin, kaempferol, luteolin, fisetin, chrysin, galangin, flavone, 3-hydroxyflavone, 5-hydroxyflavone and 7-hydroxyflavone. In the Ames assay, quercetin acted directly and its mutagenicity increased with metabolic activation. In the presence of S9 mix, kaempferol and galangin were mutagenic in the TA98 strain and kaempferol showed signs of mutagenicity in the other strains. The absence of hydroxyl groups, as in flavone, only signs of mutagenicity were shown in strain TA102, after metabolization and, among monohydroxylated flavones (3-hydroxyflavone, 5-hydroxyflavone and 7-hydroxyflavone, the presence of hydroxyl groups only resulted in minor changes. Luteolin and fisetin also showed signs of mutagenicity in strain TA102. Finally, chrysin, which has only two hydroxy groups, at the 5-OH and 7-OH positions, also did not induce mutagenic activity in any of the bacterial strains used, under either activation condition. All the flavonoids were tested at concentrations varying from 2.6 to 30.7 nmol/plate for galangin and 12.1 to 225.0 nmol/plate for other flavonoids. In light of the above, it is necessary to clarify the conditions and the mechanisms that mediate the biological effects of flavonoids before treating them as therapeutical agents, since some compounds can be biotransformed into more genotoxic products; as is the case for galangin, kaempferol and quercetin.

  15. Influence of the apical enlargement size on the endotoxin level reduction of dental root canals

    Directory of Open Access Journals (Sweden)

    Ariane Cassia Salustiano Marinho

    2012-12-01

    Full Text Available Gram-negative bacteria play an essential role in endodontic infections because they have virulence factors such as endotoxin. Due to its potential cytotoxic activity, special attention has been given to the removal/neutralization of this endotoxin in the root canal system. OBJECTIVE: The aim of this study was to evaluate the influence of the apical enlargement size (AES by using rotary instruments on the endotoxin level reduction of dental root canals. MATERIAL AND METHODS: Forty root canals of the mandibular premolar teeth were used. Escherichia coli endotoxin (055: B55 was inoculated into thirty root canals. Ten teeth served as the negative control group. After the incubation period, the first endotoxin samples were collected from the root canals with a sterile/apyrogenic paper point for the analysis of the endotoxin units (EU/mL present before instrumentation (S1. Specimen instrumentation was performed with the Mtwo® rotary system in the sequence 10/.04, 15/.05, 20/.06, 25/.06, 30/.05, 35/.04 and 40/.04. To monitor the effectiveness of increasing apical enlargement on endotoxin removal, the second endotoxin samples were collected from all the root canals after instrumentation with the following instruments: #25/.06- (S2; #30/.05- (S3; # 35/.04- (S4; and #40/.04- (S5. Limulus amebocyte lysate (LAL was used to quantify the levels of endotoxin. The results were statistically compared by using repeated measures of ANOVA with post hoc Tukey testing. RESULTS: Increasing levels of endotoxin removal was achieved by large sized apical enlargement: S2 (AES #25/.06- 89.2%, S3 (AES #30/.05- 95.9%, S4 (AES #35/.04- 97.8% and S5 (AES #40/.04- 98.2%. Substantial reduction of endotoxin content was obtained in S4 and S5 compared to S2 (p<0.05, however, the root canal preparation was not able to eliminate the endotoxin. CONCLUSIONS: Under the conditions of this study, it was concluded that the reduction of endotoxin levels of the dental root canals could be

  16. Pantoea agglomerans : a mysterious bacterium of evil and good. Part II. Deleterious effects: Dust-borne endotoxins and allergens – focus on grain dust, other agricultural dusts and wood dust

    Directory of Open Access Journals (Sweden)

    Jacek Dutkiewicz

    2015-12-01

    Full Text Available Pantoea agglomerans , a Gram-negative bacterium developing in a variety of plants as epiphyte or endophyte is particularly common in grain and grain dust, and has been identified by an interdisciplinary group from Lublin, eastern Poland, as a causative agent of work-related diseases associated with exposure to grain dust and other agricultural dusts. The concentration of [i]P. agglomerans[/i] in grain as well as in the settled grain and flour dust was found to be high, ranging from 10 4 –10 8 CFU/g, while in the air polluted with grain or flour dust it ranged from 10 3 –10 5 CFU/m 3 and formed 73.2–96% of the total airborne Gram-negative bacteria. The concentration of P. agglomerans was also relatively high in the air of the facilities processing herbs and other plant materials, while it was lower in animal farms and in wood processing facilities. Pantoea agglomerans produces a biologically-potent endotoxin (cell wall lipopolysaccharide, LPS. The significant part of this endotoxin occurs in dusts in the form of virus-sized globular nanoparticles measuring 10–50 nm that could be described as the ‘endotoxin super-macromolecules’. A highly significant relationship was found (R=0.804, P=0.000927 between the concentration of the viable P. agglomerans in the air of various agricultural and wood industry settings and the concentration of bacterial endotoxin in the air, as assessed by the Limulus test. Although this result may be interfered by the presence of endotoxin produced by other Gram-negative species, it unequivocally suggests the primary role of the P. agglomerans endotoxin as an adverse agent in the agricultural working environment, causing toxic pneumonitis (ODTS. Numerous experiments by the inhalation exposure of animals to various extracts of P. agglomerans strains isolated from grain dust, including endotoxin isolated with trichloroacetic acid (LPS-TCA, endotoxin nanoparticles isolated in sucrose gradient (VECN, and mixture of

  17. Pantoea agglomerans: a mysterious bacterium of evil and good. Part II--Deleterious effects: Dust-borne endotoxins and allergens--focus on grain dust, other agricultural dusts and wood dust.

    Science.gov (United States)

    Dutkiewicz, Jacek; Mackiewicz, Barbara; Lemieszek, Marta Kinga; Golec, Marcin; Skórska, Czesława; Góra-Florek, Anna; Milanowski, Janusz

    2016-01-01

    Pantoea agglomerans, a Gram-negative bacterium developing in a variety of plants as epiphyte or endophyte is particularly common in grain and grain dust, and has been identified by an interdisciplinary group from Lublin, eastern Poland, as a causative agent of work-related diseases associated with exposure to grain dust and other agricultural dusts. The concentration of P. agglomerans in grain as well as in the settled grain and flour dust was found to be high, ranging from 10(4)-10(8) CFU/g, while in the air polluted with grain or flour dust it ranged from 10(3)-10(5) CFU/m(3) and formed 73.2-96% of the total airborne Gram-negative bacteria. The concentration of P. agglomerans was also relatively high in the air of the facilities processing herbs and other plant materials, while it was lower in animal farms and in wood processing facilities. Pantoea agglomerans produces a biologically-potent endotoxin (cell wall lipopolysaccharide, LPS). The significant part of this endotoxin occurs in dusts in the form of virus-sized globular nanoparticles measuring 10-50 nm that could be described as the 'endotoxin super-macromolecules'. A highly significant relationship was found (R=0.804, P=0.000927) between the concentration of the viable P. agglomerans in the air of various agricultural and wood industry settings and the concentration of bacterial endotoxin in the air, as assessed by the Limulus test. Although this result may be interfered by the presence of endotoxin produced by other Gram-negative species, it unequivocally suggests the primary role of the P. agglomerans endotoxin as an adverse agent in the agricultural working environment, causing toxic pneumonitis (ODTS). Numerous experiments by the inhalation exposure of animals to various extracts of P. agglomerans strains isolated from grain dust, including endotoxin isolated with trichloroacetic acid (LPS-TCA), endotoxin nanoparticles isolated in sucrose gradient (VECN), and mixture of proteins and endotoxin obtained

  18. Proanthocyanidin-based Endotoxin Removal

    Science.gov (United States)

    2014-01-16

    synthesis or purification of a variety of compounds with LPS-binding activities [2–11]. Polymyxin B (PMB) is the most commonly employed agent for removal... polyphenolics are accessible to the reagents in a manner similar to those in free in solution. The analysis also assumes that all degrees of... Synthesis and Application of a Novel Ligand for Affinity Chromatography Based Removal of Endotoxin from Antibodies,” Bioconjugate Chemistry 18, 559

  19. Preclinical test: bacterial reverse mutation test for 18F-fluorocholine produced in CDTN

    International Nuclear Information System (INIS)

    Mendes, Bruno M.; Bispo, Ana Carolina A.; Campos, Danielle C.; Silva, Juliana B.

    2013-01-01

    The choline labeled with fluorine-18 (18FCH) is being considered as a great importance radiopharmaceutical due to its effective detection of many type of malignant neoplasm. The research related to 18 F-fluorocholine synthesis in CDTN was initiated in 2010. In order to obtain clinical research approval, as well as to register 18 FCH for marketing, safety and efficacy preclinical testing are required. The present work evaluated the 18 FCH genotoxic potential through the bacterial reverse mutation test (Ames test) using Salmonella typhimurium TA-98, TA-100, TA-1535 and TA-1537 strains and Escherichia coli WP2 uvrA strain. The reverse mutation test in bacteria for fluorcolina was conducted in two stages. Initially the method was applied to 'cold' fluorocholine molecule (19FCH). Subsequently, the decayed product of 18 FCH synthesis was evaluated. The first step was performed in order to examine the FCH molecule mutagenicity. The second was carried out to determine the mutagenic potential of final product. All strains were tested in triplicate for each exposure concentration, in the presence and absence of metabolic activation (S-9 mix - 10%). There were no statistically significant increases in revertant colonies rate for any strains tested after their exposure to decayed 18 FCH or 19 FCH. The number of revertant colonies in positive controls was significantly higher than that observed in significant increases in revertant colonies rate for any strains tested after their exposure to decayed 18 FCH or 19 FCH. The number of revertant colonies in positive controls was significantly higher than that observed in negative controls. Based on results of this assay, 18 FCH and 19 FCH, at tested doses, were found to be non-mutagenic in bacterial reverse mutation test. (author)

  20. Endotoxins in surgical instruments of hip arthroplasty.

    Science.gov (United States)

    Goveia, Vania Regina; Mendoza, Isabel Yovana Quispe; Guimarães, Gilberto Lima; Ercole, Flavia Falci; Couto, Bráulio Roberto Gonçalves Marinho; Leite, Edna Marilea Meireles; Stoianoff, Maria Aparecida Resende; Ferreira, José Antonio Guimarães

    2016-01-01

    To investigate endotoxins in sterilized surgical instruments used in hip arthroplasties. A descriptive exploratory study conducted in a public teaching hospital. Six types of surgical instruments were selected, namely: acetabulum rasp, femoral rasp, femoral head remover, chisel box, flexible bone reamer and femoral head test. The selection was based on the analysis of the difficulty in removing bone and blood residues during cleaning. The sample was made up of 60 surgical instruments, which were tested for endotoxins in three different stages. The EndosafeTM Gel-Clot LAL (Limulus Amebocyte Lysate method) was used. There was consistent gel formation with positive analysis in eight instruments, corresponding to 13.3%, being four femoral rasps and four bone reamers. Endotoxins in quantity ≥0.125 UE/mL were detected in 13.3% of the instruments tested. Investigar endotoxinas em instrumentais cirúrgicos esterilizados empregados em artroplastias do quadril. Estudo exploratório, descritivo, desenvolvido em um hospital público de ensino. Foram selecionados seis tipos de instrumentais, a saber: raspa acetabular, raspa femural, saca-cabeça de fêmur, formão box, fresa de fêmur e cabeça de prova de fêmur. A seleção foi feita a partir da análise da dificuldade para a remoção de resíduos de sangue e osso durante a limpeza. A amostra foi constituída por 60 instrumentais cirúrgicos, que foram testados para endotoxinas em três momentos distintos. Foi utilizado o método de gel-clot pelo Limulus Amebócito Lisado (LAL) Endosafe(tm). Houve formação de gel consistente com análise positiva em oito instrumentais, o que corresponde a 13,3%, sendo quatro raspas de fêmur e quatro fresas de fêmur. Foram detectadas endotoxinas em quantidade ≥0,125 UE/mL em 13,3% dos instrumentais testados.

  1. Ceftaroline activity tested against contemporary Latin American bacterial pathogens (2011

    Directory of Open Access Journals (Sweden)

    Robert K. Flamm

    2014-03-01

    Full Text Available A total of 2484 target bacterial pathogens were collected (one per patient episode from patients in 16 Latin American medical centers located in seven nations during 2011. Isolate identity was confirmed at a coordinating laboratory and susceptibility testing was performed for ceftaroline and comparator agents according to reference broth microdilution methods. A total of 30.0% of isolates were from respiratory tract, 29.4% from skin and skin structure, 21.4% from blood stream, 7.9% from urinary tract and 11.3% from other sites. Ceftaroline was active against Staphylococcus aureus (42.8% MRSA with 83.6% of the isolates at ≤1 mg/L and all isolates at ≤2 mg/L (MIC5090, 0.25/2 mg/L. National MRSA rates ranged from a low of 28.8% in Colombia to a high of 68.1% in Chile. All Streptococcus pyogenes and Streptococcus agalactiae were susceptible to ceftaroline (MIC50/90 values were at ≤0.015/≤0.015 mg/L for both. All Streptococcus pneumoniae were susceptible to ceftaroline, linezolid, tigecycline and vancomycin. Susceptibility to ceftriaxone was at 88.4% (CLSI non-meningitis interpretive criteria and 73.9% (CLSI meningitis interpretive criteria for all S. pneumoniae. Ceftriaxone susceptibility was only at 33.3% (CLSI non-meningitis interpretive criteria and 0.0% (CLSI meningitis interpretive criteria for penicillin-intermediate (penicillin MIC, 4 mg/L strains. All Haemophilus influenzae (29.4% β-lactamase-positive isolates were susceptible to ceftaroline, amoxicillin–clavulanate, ceftriaxone, and levofloxacin. For the Latin American region, the ESBL-phenotype rate was 37.6% for Escherichia coli and 53.3% for Klebsiella pneumoniae. Ceftaroline was not active against ESBL-phenotype strains but was active against >90.0% of the non-ESBL-phenotype. The spectrum of activity of ceftaroline against pathogens from Latin America indicates that it merits further study for its potential use in the Latin American region.

  2. Effect of Solcoseryl on the clinical course of experimental Escherichia coli-endotoxin mastitis.

    Science.gov (United States)

    Ziv, G; Jöchle, W

    1981-09-01

    Experimental Escherichia coli-endotoxin mastitis was induced in a single quarter in twenty-eight cows. The inflamed quarters of six of the cows were treated with 50 mg Solcoseryl infusion in an oil base starting 4-6 h after endotoxin infusion, and four additional infusions were given at 12-h intervals. The inflamed quarters of eight of the cows were similarly treated with 200 mg Solcoseryl whereas the remaining fourteen cows served as control. Solcoseryl treatment did not alter the systemic or local course of acute mastitis. Local reaction, as assessed by the California Mastitis Test (CMT), however, subsided considerably sooner in quarters treated with Solcoseryl, and the effect of Solcoseryl in hastening udder tissue repair processes appeared to be dose dependent. The 200 mg dose of Solcoseryl resulted in pre-endotoxin CMT scores as early as 6 days after endotoxin infusion.

  3. Actions of four organic acids in radix isatidis on endotoxin-neutralization investigated by kinetic turbidimetric assay.

    Science.gov (United States)

    Ma, Li; He, Ying-jun; Li, You; Gong, Mu-xin

    2012-06-01

    To investigate anti-endotoxin action of four OAs reacted with endotoxin by the LAL assay with KTA. Using a incubating kinetic tube reader and kinetic turbidimetric assay (KTA), the concentration-response time curve of endotoxin reacted with limulus amebocyte lysate (LAL) at 37 degrees C were obtained and the action of four organic acids (OAs) on it were investigated. The four OAs were benzoic acid, salicylic acid, syringic acid and 2-amino-benzoic acid from Radix isatidis. Meanwhile, the temperature variation caused by endotoxin with the four OAs was studied by the rabbit pyrogen test (RPT). It was showed that a low concentration (1 mg/mL) of the four OAs had a little effect of anti-endotoxin, and when the concentrations of the four OAs were 30 mg/mL, the endotoxin was neutralized completely. The relationships between the concentrations of endotoxin and the OAs were all linear with correlation coefficients of greater than 0.9995, indicating that the four OAs all had strong anti-endotoxin action, while syringic acid had the strongest action among the four OAs with IC50 of 12.84 mg/mL. The investigations of KTA agreed well with the results obtained by means of RPT.

  4. Endotoxin Preconditioning Reprograms S1 Tubules and Macrophages to Protect the Kidney.

    Science.gov (United States)

    Hato, Takashi; Zollman, Amy; Plotkin, Zoya; El-Achkar, Tarek M; Maier, Bernhard F; Pay, S Louise; Dube, Shataakshi; Cabral, Pablo; Yoshimoto, Momoko; McClintick, Jeanette; Dagher, Pierre C

    2018-01-01

    Preconditioning with a low dose of endotoxin confers unparalleled protection against otherwise lethal models of sepsis. The mechanisms of preconditioning have been investigated extensively in isolated immune cells such as macrophages. However, the role of tissue in mediating the protective response generated by preconditioning remains unknown. Here, using the kidney as a model organ, we investigated cell type-specific responses to preconditioning. Compared with preadministration of vehicle, endotoxin preconditioning in the cecal ligation and puncture mouse model of sepsis led to significantly enhanced survival and reduced bacterial load in several organs. Furthermore, endotoxin preconditioning reduced serum levels of proinflammatory cytokines, upregulated molecular pathways involved in phagocytosis, and prevented the renal function decline and injury induced in mice by a toxic dose of endotoxin. The protective phenotype involved the clustering of macrophages around S1 segments of proximal tubules, and full renal protection required both macrophages and renal tubular cells. Using unbiased S1 transcriptomic and tissue metabolomic approaches, we identified multiple protective molecules that were operative in preconditioned animals, including molecules involved in antibacterial defense, redox balance, and tissue healing. We conclude that preconditioning reprograms macrophages and tubules to generate a protective environment, in which tissue health is preserved and immunity is controlled yet effective. Endotoxin preconditioning can thus be used as a discovery platform, and understanding the role and participation of both tissue and macrophages will help refine targeted therapies for sepsis. Copyright © 2018 by the American Society of Nephrology.

  5. Effects of Endotoxin and Psychological Stress on Redox Physiology, Immunity and Feather Corticosterone in Greenfinches.

    Directory of Open Access Journals (Sweden)

    Richard Meitern

    Full Text Available Assessment of costs accompanying activation of immune system and related neuroendocrine pathways is essential for understanding the selective forces operating on these systems. Here we attempted to detect such costs in terms of disruption to redox balance and interference between different immune system components in captive wild-caught greenfinches (Carduelis chloris. Study birds were subjected to an endotoxin-induced inflammatory challenge and temporary exposure to a psychological stressor (an image of a predator in a 2*2 factorial experiment. Injection of bacterial endotoxin resulted in up-regulation of two markers of antioxidant protection - erythrocyte glutathione, and plasma oxygen radical absorbance (OXY. These findings suggest that inflammatory responses alter redox homeostasis. However, no effect on markers of oxidative damage to proteins or DNA in erythrocytes could be detected. We found no evidence that the endotoxin injection interfered with antibody production against Brucella abortus antigen or the intensity of chronic coccidiosis. The hypothesis of within-immune system trade-offs as a cost of immunity was thus not supported in our model system. We showed for the first time that administration of endotoxin can reduce the level of corticosterone deposited into feathers. This finding suggests a down-regulation of the corticosterone secretion cascade due to an endotoxin-induced immune response, a phenomenon that has not been reported previously. Exposure to the predator image did not affect any of the measured physiological parameters.

  6. Effects of Endotoxin and Psychological Stress on Redox Physiology, Immunity and Feather Corticosterone in Greenfinches

    Science.gov (United States)

    Meitern, Richard; Sild, Elin; Lind, Mari-Ann; Männiste, Marju; Sepp, Tuul; Karu, Ulvi; Hõrak, Peeter

    2013-01-01

    Assessment of costs accompanying activation of immune system and related neuroendocrine pathways is essential for understanding the selective forces operating on these systems. Here we attempted to detect such costs in terms of disruption to redox balance and interference between different immune system components in captive wild-caught greenfinches (Carduelis chloris). Study birds were subjected to an endotoxin-induced inflammatory challenge and temporary exposure to a psychological stressor (an image of a predator) in a 2*2 factorial experiment. Injection of bacterial endotoxin resulted in up-regulation of two markers of antioxidant protection – erythrocyte glutathione, and plasma oxygen radical absorbance (OXY). These findings suggest that inflammatory responses alter redox homeostasis. However, no effect on markers of oxidative damage to proteins or DNA in erythrocytes could be detected. We found no evidence that the endotoxin injection interfered with antibody production against Brucella abortus antigen or the intensity of chronic coccidiosis. The hypothesis of within-immune system trade-offs as a cost of immunity was thus not supported in our model system. We showed for the first time that administration of endotoxin can reduce the level of corticosterone deposited into feathers. This finding suggests a down-regulation of the corticosterone secretion cascade due to an endotoxin-induced immune response, a phenomenon that has not been reported previously. Exposure to the predator image did not affect any of the measured physiological parameters. PMID:23805316

  7. Effects of Endotoxin and Psychological Stress on Redox Physiology, Immunity and Feather Corticosterone in Greenfinches.

    Science.gov (United States)

    Meitern, Richard; Sild, Elin; Lind, Mari-Ann; Männiste, Marju; Sepp, Tuul; Karu, Ulvi; Hõrak, Peeter

    2013-01-01

    Assessment of costs accompanying activation of immune system and related neuroendocrine pathways is essential for understanding the selective forces operating on these systems. Here we attempted to detect such costs in terms of disruption to redox balance and interference between different immune system components in captive wild-caught greenfinches (Carduelis chloris). Study birds were subjected to an endotoxin-induced inflammatory challenge and temporary exposure to a psychological stressor (an image of a predator) in a 2*2 factorial experiment. Injection of bacterial endotoxin resulted in up-regulation of two markers of antioxidant protection - erythrocyte glutathione, and plasma oxygen radical absorbance (OXY). These findings suggest that inflammatory responses alter redox homeostasis. However, no effect on markers of oxidative damage to proteins or DNA in erythrocytes could be detected. We found no evidence that the endotoxin injection interfered with antibody production against Brucella abortus antigen or the intensity of chronic coccidiosis. The hypothesis of within-immune system trade-offs as a cost of immunity was thus not supported in our model system. We showed for the first time that administration of endotoxin can reduce the level of corticosterone deposited into feathers. This finding suggests a down-regulation of the corticosterone secretion cascade due to an endotoxin-induced immune response, a phenomenon that has not been reported previously. Exposure to the predator image did not affect any of the measured physiological parameters.

  8. Removal of endotoxins from bacteriophage preparations by extraction with organic solvents.

    Directory of Open Access Journals (Sweden)

    Bożena Szermer-Olearnik

    Full Text Available Lipopolysaccharide (LPS, endotoxin, pyrogen constitutes a very troubling contaminant of crude phage lysates produced in Gram-negative bacteria. Toxicity of LPS depends on the strong innate immunity response including the cytokines. Therefore, its removal is important for bacteriophage applications. In this paper, we present a procedure for extractive removal of endotoxin from bacteriophage preparations with water immiscible solvents (1-octanol or 1-butanol. During extraction most of the phage lytic activity is retained in the aqueous phase, while endotoxin accumulates in the organic solvent. The levels of endotoxin (expressed as endotoxin units, EU in the aqueous bacteriophage-containing fraction determined by limulus amebocyte lysate or EndoLISA assay were exceptionally low. While the initial endotoxin levels in the crude phage lysates ranged between 10(3 and 10(5 EU/ml the average level after organic extraction remaining in the aqueous fraction was 5.3 EU/ml. These values when related to phage titers decreased from 10(3-10(5 EU/10(9 PFU (plaque forming units down to an average of 2.8 EU/10(9 PFU. The purification procedure is scalable, efficient and applicable to all the bacteriophages tested: T4, HAP1 (E. coli and F8 (P. aeruginosa.

  9. Endotoxin concentration in treated water of all hemodialysis units in Greece and inquisition of influencing factors.

    Science.gov (United States)

    Arvanitidou, M; Spaia, S; Askepidis, N; Kanetidis, D; Pazarloglou, M; Katsouyannopoulos, V; Vayonas, G

    1999-01-01

    Mains and purified water samples from all hemodialysis centers in Greece were surveyed to assess hemodialysis water quality and the potential consequences on the dialysis population of any microbial and endotoxin contamination. Total heterotrophic bacteria counts were estimated employing the pour-plate method, the membrane filter technique, for total coliforms, fecal coliforms, enterococci and Pseudomonas spp., and the most probable number method for sulfite-reducing clostridia. Overall 170 paired samples were tested. Endotoxin concentrations were assayed in treated water samples, by the Limulus Amebocyte Lysate method, employing a chromogenic substrate. Endotoxin concentration varied from 0-30 EU/ml and exceeded 5 EU/ml in 30.6% of the centers. Endotoxin contaminated samples showed higher counts of total heterotrophic bacteria, fecal coliforms, enterococci and Pseudomonas spp. than the rest of the samples, though the difference was significant only for total heterotrophic bacteria and enterococci. Additionally, samples with endotoxin contamination derived from the mains water had significantly higher counts of fecal coliforms, enterococci and Pseudomonas spp. Endotoxin concentration was correlated with the presence of a deionization system, counts of fecal coliforms in supply water and counts of total coliforms, fecal coliforms and enterococci in treated water. These results demonstrate that hemodialysis centers in Greece need to monitor and preventively maintain the entire hemodialysis system, in order to ensure renal replacement therapy of good quality.

  10. Endotoxin levels and contribution factors of endotoxins in resident, school, and office environments - A review

    Science.gov (United States)

    Salonen, Heidi; Duchaine, Caroline; Létourneau, Valérie; Mazaheri, Mandana; Laitinen, Sirpa; Clifford, Sam; Mikkola, Raimo; Lappalainen, Sanna; Reijula, Kari; Morawska, Lidia

    2016-10-01

    As endotoxin exposure has known effects on human health, it is important to know the generally existing levels of endotoxins as well as their contributing factors. This work reviews current knowledge on the endotoxin loads in settled floor dust, concentrations of endotoxins in indoor air, and different environmental factors potentially affecting endotoxin levels. The literature review consists of peer-reviewed manuscripts located using Google and PubMed, with search terms based on individual words and combinations. References from relevant articles have also been searched. Analysis of the data showed that in residential, school, and office environments, the mean endotoxin loads in settled floor dust varied between 660 and 107,000 EU/m2, 2180 and 48,000 EU/m2, and 2700 and 12,890 EU/m2, respectively. Correspondingly, the mean endotoxin concentrations in indoor air varied between 0.04 and 1610 EU/m3 in residences, and 0.07 and 9.30 EU/m3 in schools and offices. There is strong scientific evidence indicating that age of houses (or housing unit year category), cleaning, farm or rural living, flooring materials (the presence of carpets), number of occupants, the presence of dogs or cats indoors, and relative humidity affect endotoxin loads in settled floor dust. The presence of pets (especially dogs) was extremely strongly associated with endotoxin concentrations in indoor air. However, as reviewed articles show inconsistency, additional studies on these and other possible predicting factors are needed.

  11. 40 CFR 799.9510 - TSCA bacterial reverse mutation test.

    Science.gov (United States)

    2010-07-01

    ... SUBSTANCES CONTROL ACT (CONTINUED) IDENTIFICATION OF SPECIFIC CHEMICAL SUBSTANCE AND MIXTURE TESTING... point mutations, which involve substitution, addition or deletion of one or a few DNA base pairs. The... amino acid required by the parent test strain. (2) Point mutations are the cause of many human genetic...

  12. Testing potential effects of maize expressing the Bacillus thuringiensis Cry1Ab endotoxin (Bt maize) on mycorrhizal fungal communities via DNA- and RNA-based pyrosequencing and molecular fingerprinting.

    Science.gov (United States)

    Verbruggen, Erik; Kuramae, Eiko E; Hillekens, Remy; de Hollander, Mattias; Kiers, E Toby; Röling, Wilfred F M; Kowalchuk, George A; van der Heijden, Marcel G A

    2012-10-01

    The cultivation of genetically modified (GM) crops has increased significantly over the last decades. However, concerns have been raised that some GM traits may negatively affect beneficial soil biota, such as arbuscular mycorrhizal fungi (AMF), potentially leading to alterations in soil functioning. Here, we test two maize varieties expressing the Bacillus thuringiensis Cry1Ab endotoxin (Bt maize) for their effects on soil AM fungal communities. We target both fungal DNA and RNA, which is new for AM fungi, and we use two strategies as an inclusive and robust way of detecting community differences: (i) 454 pyrosequencing using general fungal rRNA gene-directed primers and (ii) terminal restriction fragment length polymorphism (T-RFLP) profiling using AM fungus-specific markers. Potential GM-induced effects were compared to the normal natural variation of AM fungal communities across 15 different agricultural fields. AM fungi were found to be abundant in the experiment, accounting for 8% and 21% of total recovered DNA- and RNA-derived fungal sequences, respectively, after 104 days of plant growth. RNA- and DNA-based sequence analyses yielded most of the same AM fungal lineages. Our research yielded three major conclusions. First, no consistent differences were detected between AM fungal communities associated with GM plants and non-GM plants. Second, temporal variation in AMF community composition (between two measured time points) was bigger than GM trait-induced variation. Third, natural variation of AMF communities across 15 agricultural fields in The Netherlands, as well as within-field temporal variation, was much higher than GM-induced variation. In conclusion, we found no indication that Bt maize cultivation poses a risk for AMF.

  13. Endotoxin exposure in sewage treatment workers: investigation of exposure variability and comparison of analytical techniques.

    Science.gov (United States)

    Spaan, Suzanne; Smit, Lidwien A M; Eduard, Wijnand; Larsson, Lennart; Arts, Huib J J M; Wouters, Inge M; Heederik, Dick J J

    2008-01-01

    Objectives were to give an overview of endotoxin exposure and its determinants in sewage treatment workers, and to study exposure to culturable and non-culturable microorganisms and the applicability of the LAL assay in this work environment. In 43 Dutch sewage treatment plants 470 full-shift, 123 task-based personal and 54 stationary inhalable dust samples were collected. Endotoxin concentration was determined with the LAL-assay. Mixed effects models were used to investigate possible determinants of exposure. Simultaneous parallel filter samples, impinger samples and viable total bacteria and Gram-negative bacterial samples were taken to compare analytical techniques. Filter and impinger samples were analyzed with the LAL-assay, gas chromatography-mass spectrometry (GC-MS) and fluorescence microscopy. Endotoxin exposure levels were moderate to low (geometric mean personal exposure 27 EU/m(3), stationary 33 EU/m(3), task-based 64 EU/m(3)), yet differences between jobs and sources and some determinants of exposure were identified. Exposure varied more from day to day than between workers. Concentrations in filter samples were higher and more consistent than in impinger samples. Fungi and Gram-positive bacteria were found in higher levels than Gram-negative bacteria. The LAL assay and GC-MS showed comparable endotoxin levels. Endotoxin exposure in Dutch sewage treatment workers was relatively low. Comparison of sampling and analytical techniques suggests that the LAL-assay did not result in much exposure misclassification. It thus seems justified to perform filter measurements in combination with the LAL-assay to measure endotoxin exposure in sewage treatment plants.

  14. Molecular assessment of bacterial community dynamics and functional endpoints during sediment bioaccumulation test

    NARCIS (Netherlands)

    Diepens, N.J.; Dimitrov, M.R.; Koelmans, A.A.; Smidt, H.

    2015-01-01

    Whole sediment toxicity tests play an important role in environmental risk assessment of organic chemicals. It is not clear, however, to what extent changing microbial community composition and associated functions affect sediment test results. We assessed the development of bacterial communities in

  15. Endotoxin pretreatment modifies peristalsis and attenuates the antipropulsive action of adrenoceptor agonists in the guinea-pig small intestine.

    Science.gov (United States)

    Fruhwald, S; Herk, E; Schöll, G; Shahbazian, A; Hammer, H F; Metzler, H; Holzer, P

    2004-04-01

    The action of endotoxin to alter gastrointestinal motility in vivo may reflect a direct effect on the gut or result from vascular and other systemic manifestations of this sepsis model. Here we examined whether in vivo pretreatment of guinea-pigs with endotoxin modifies peristalsis in the isolated gut and influences the antipropulsive action of adrenoceptor agonists. Distension-induced peristalsis was recorded in fluid-perfused segments of the small intestine taken from animals pretreated intraperitoneally with endotoxin (1 mg kg(-1)Escherichia coli lipopolysaccharide) or vehicle 4 or 20 h before. Clonidine, adrenaline, noradrenaline, dopamine and dobutamine inhibited peristalsis with differential potency. Endotoxin pretreatment lowered the peristaltic pressure threshold and altered other parameters of baseline peristalsis in a time-related manner. The potency and efficacy of clonidine to inhibit peristalsis were markedly decreased after endotoxin administration, while the potency of the other test drugs was less attenuated. The antipropulsive action of clonidine in control segments was reduced by yohimbine and prazosin, whereas in segments from endotoxin-pretreated animals it was antagonized by yohimbine but not prazosin. We conclude that systemic endotoxin pretreatment of guinea-pigs modifies baseline peristalsis by an action on the gut and inhibits the antipropulsive action of adrenoceptor agonists through changes in adrenoceptor activity.

  16. Cytokine release from human peripheral blood leucocytes incubated with endotoxin with and without prior infection with influenza virus

    DEFF Research Database (Denmark)

    Banner, Jytte; Smith, H; Sweet, C

    1993-01-01

    Previous work with a neonatal ferret model for human SIDS had indicated that inflammation caused by a combination of influenza virus and bacterial endotoxin may be a cause of human SIDS. To determine whether cytokines may be involved in this inflammatory response, levels of interleukin (IL)-1 beta...

  17. Fourier Transform Infrared Spectroscopy as a Tool in Analysis of Proteus mirabilis Endotoxins.

    Science.gov (United States)

    Żarnowiec, Paulina; Czerwonka, Grzegorz; Kaca, Wiesław

    2017-01-01

    Fourier transform infrared spectroscopy (FT-IR) was used to scan whole bacterial cells as well as lipopolysaccharides (LPSs, endotoxins) isolated from them. Proteus mirabilis cells, with chemically defined LPSs, served as a model for the ATR FT-IR method. The paper focuses on three steps of infrared spectroscopy: (1) sample preparation, (2) IR scanning, and (3) multivariate analysis of IR data (principal component analysis, PCA).

  18. Latex particle agglutination test as an adjunct to the diagnosis of bacterial meningitis

    Directory of Open Access Journals (Sweden)

    Surinder K

    2007-01-01

    Full Text Available The present study aimed to review the results of microscopic examination, routine culture and antigen detection by latex particle agglutination test (LPAT, in order to evaluate the diagnostic value of the LPAT in establishing the aetiological diagnosis of bacterial meningitis. LPAT was done in 65 clinically suspected meningitis cases ranging from 5 days to 60 years of age and was compared with culture and Gram stain. Using LPAT, an aetiological diagnosis could be done in 10 out of 65 (15.4% cases of bacterial meningitis. In contrast, Gram stain and culture showed 16.9 and 23.1% positivity, respectively. LPAT correlated well with Gram stain and culture and can be recommended as an adjunct laboratory test for rapid aetiological diagnosis of bacterial meningitis for prompt institution of proper antibiotics.

  19. Time window for positive cerebrospinal fluid broad-range bacterial PCR and Streptococcus pneumoniae immunochromatographic test in acute bacterial meningitis.

    Science.gov (United States)

    Brink, Magnus; Welinder-Olsson, Christina; Hagberg, Lars

    2015-01-01

    Reliable microbiological tests are essential for the diagnosis of acute bacterial meningitis (ABM). In this study we investigated the time period after the start of antibiotic therapy during which culture, polymerase chain reaction (PCR) and the immunochromatographic test (ICT) are able to detect bacteria in cerebrospinal fluid (CSF). The study was performed on CSF samples from adults with ABM admitted to the Department of Infectious Diseases, Sahlgrenska University Hospital, Gothenburg, Sweden, from January 2007 to April 2014. In addition to the initial lumbar puncture (LP), the participants underwent one or two more LPs during 10 days following the start of antibiotics. The analyses performed on the CSF samples were culture, PCR and ICT. The study comprised 70 CSF samples from 25 patients with ABM. A bacterium could be identified by CSF culture in 44%, by blood culture in 58% and by PCR in 100% of the patients. There were no positive CSF cultures in samples taken later than the day of starting antibiotics. PCR was positive in 89% on days 1-3, 70% on days 4-6 and 33% on days 7-10. For cases of pneumococcal meningitis, the ICT was positive in 88% on days 1-3, 90% on days 4-6 and 75% on days 7-10. This study shows that PCR is highly sensitive for bacterial detection in CSF samples taken up to 1 week into antibiotic therapy. The ICT is highly sensitive for the detection of pneumococci in CSF samples taken during the first week of antibiotic treatment.

  20. Effectiveness of castor oil extract on Escherichia coli and its endotoxins in root canals.

    Science.gov (United States)

    Valera, Marcia Carneiro; Maekawa, Lilian Eiko; Chung, Adriana; de Oliveira, Luciane Dias; Carvalho, Claudio Antonio Talge; Koga-Ito, Cristiane Yumi; Jorge, Antonio Olavo Cardoso

    2012-01-01

    This in vitro study sought to evaluate the effectiveness of castor oil extract used as an irrigating solution on Escherichia coli and its endotoxins in root canals. Sixty single-rooted teeth were prepared (using castor oil extract as irrigating solution) and divided into five groups (n = 12): Group 1 samples were treated with calcium hydroxide (Ca(OH)2), Group 2 samples were treated with polymyxin B, Group 3 samples were treated with Ca(OH)2 and 2% chlorhexidine gel (CHX), and Group 4 samples were treated with castor oil extract. A control group used physiological saline solution as an irrigant. Canal content samples were collected at four different times: immediately after instrumentation, seven days after instrumentation, after 14 days of intracanal medication, and seven days after removal of intracanal medication. A plating method was used to assess antimicrobial activity and the quantification of endotoxins was evaluated by the chromogenic Limulus lysate assay. Data were submitted to ANOVA and a Dunn test (a = 5%). Irrigation with castor oil extract decreased E. coli counts but had no effect on the level of endotoxins. Samples taken seven days after removal of medication revealed a significant reduction in endotoxin levels in Groups 3 and 4. Compared to the saline solution irrigation, castor oil extract decreased microorganism counts in root canals immediately after canal preparation. None of the medications used completely eliminated endotoxins in the root canal.

  1. Effects of endotoxin on the lactating mouse

    International Nuclear Information System (INIS)

    Carr, J.K.

    1985-01-01

    The regulation of endogenous mouse mammary tumor virus (MMTV) sequences in trans by a host gene, the Lps locus on mouse chromosome 4, was suspected from a genetic linkage analysis. The Lps locus mediates the mouse's response to the injection of lipopolysaccharide (LPS) in the responder mouse while mice with the deficient allele are incapable of responding. Others have found that endotoxin exposure reduces milk production in lactating animals. This observation was confirmed in mice and extended by examining 125 I-prolactin binding to liver membranes of lactating mice. Endotoxin treatment of responder mice increases liver prolactin binding within 15 minutes, followed by a decline over 6 hours. Scatchard analysis shows that the immediate increase comes from both increased affinity and abundance of the prolactin receptor. No such change in prolactin binding is seen in the non-responder following endotoxin treatment nor in 125 I-insulin binding in responders

  2. The effect of endotoxin on preirradiated mice

    Energy Technology Data Exchange (ETDEWEB)

    Oehlert, W.; Oehlert, M. (Freiburg Univ. (Germany). Inst. fuer Pathologie); Moenig, H.; Konermann, G. (Freiburg Univ. (Germany). Inst. fuer Biophysik und Strahlenbiologie)

    1992-12-01

    Adult male mice were given a whole body irradiation with non-lethal doses of 2.5 or 5 Gy. Unirradiated animals served as controls. The animals (including controls) received a single injection of endotoxin (LPS from Salmonella abortus equi) with doses of 100, 200 or 400 [mu]g one day up to one year after irradiation. Twelve, 24 or 48 hours after lipopolysaccharide (LPS) application the animals were killed and dissected. Animals which died spontaneously were also examined. Liver, lung, kidney, small intestine, and stomach were histologically investigated. The histological findings showed, that differences exist between irradiated and unirradiated mice and that the cause of death is also different for animals dying spontaneously. The investigations have shown that after irradiation phases of different degrees of sensitivity with regard to the endotoxin response exist. This behaviour can be observed by different lethality rates or in the light of the histological results. Moreover, the histological findings have shown, that distinct regenerative changes occur first of all in the liver, in the mucosa of small intestine, and the gastric mucosa, in which the number of differntiated cells compared with the mitotic active cells is reduced. It can be ascertained, that a whole body irradiation with 2.5 to 5 Gy enhances an additional injury by endotoxin weeks to months later. Contrary to this a preirradiation a few days before endotoxin application leads to a 'protection' against the efficacy of endotoxin. These findings can be explained by modes of action described in literature, according to which endotoxins induce the formation of highly active mediators especially the tumor necrosis factor. (orig.).

  3. Effect of different methods of sterilization on the inactivation of bacterial endotoxin (LPS in endodontic files Efeito de diferentes métodos de esterilização na inativação da endotoxina bacteriana (LPS presnete em limas endodônicas

    Directory of Open Access Journals (Sweden)

    Raquel Assed Bezerra da Silva

    2007-06-01

    Full Text Available This study evaluated the presence of lipopolysaccharide (LPS in endodontic files after in vitro contamination with E. coli LPS and sterilization in dry heat or wet heat, with or without previous immersion in a Ca(OH2 suspension. LPS was quantified using the Kinetic QCL TM test and data were analyzed statistically by the t-test. LPS was quantified only in the contaminated group, not submitted to any immersion or sterilization procedure (0.262±0.1296 endotoxin units/mL (p=0.0003. In conclusion, both wet heat and dry heat sterilization were effective in inactivating LPS without the need of previous immersion of the files in a Ca(OH2 suspension.Este estudo avaliou a presença de endotoxina (LPS em limas endodônticas após contaminação in vitro com LPS de E. coli e esterilização em autoclave ou forno de Pasteur, com ou sem imersão prévia em suspensão de hidróxido de cálcio. A quantificação do LPS foi efetuada pelo teste Kinetic QCL TM, e os resultados submetidos à análise estatística (teste t. LPS foi quantificado apenas no grupo contaminado e não submetido a nenhum procedimento de imersão ou esterilização (0,262±0,1296 unidades de endotoxina/mL (p=0,0003. Concluiu-se que a esterilização das limas em autoclave ou forno de Pasteur foi eficaz na inativação do LPS, não sendo necessária a sua imersão prévia em suspensão de hidróxido de cálcio.

  4. Growth and endotoxin production of Yersinia enterocolitica and Enterobacter agglomerans in packed erythrocytes.

    Science.gov (United States)

    Arduino, M J; Bland, L A; Tipple, M A; Aguero, S M; Favero, M S; Jarvis, W R

    1989-07-01

    Since 1987, the Centers for Disease Control investigated six cases of transfusion-associated sepsis. All six patients developed septic shock after receiving units of packed erythrocytes (PRBCs) contaminated with Yersinia enterocolitica (five patients) and Enterobacter agglomerans (one patient); three of the blood recipients died. We studied the growth and endotoxin production of Y. enterocolitica and E. agglomerans in units of PRBCs stored at 4 degrees C for 60 days. When PRBCs were inoculated with 0.1 to 1.0 CFU of these organisms per ml, both Y. enterocolitica and E. agglomerans entered log-phase growth 2 to 3 weeks after inoculation; generation times were 15 and 22 h, respectively. Endotoxin was first detected at 3 weeks following inoculation, and the concentration paralleled the log phase of growth of the strains tested. These data show that prolonged storage of PRBCs at 4 degrees C provides conditions that allow these two organisms to grow and subsequently produce high concentrations of endotoxin.

  5. Endotoxin Binding by Sevelamer: Potential Impact on Nutritional Status

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    Natsuki Kubotera

    2013-01-01

    Full Text Available Patients on hemodialysis (HD have a high burden of chronic inflammation induced associated with multiple comorbidities including poor nutritional status. Endotoxin (ET is a Gram-negative bacterial cell wall component and a potent stimulus for innate immune system activation leading to the transcription of proinflammatory cytokines (e.g., IL-1, IL-6, and TNFα that adversely affect protein metabolism and nutrition. Several cross-sectional observational studies have found that elevated serum ET concentrations in hemodialysis patients are associated with lower serum albumin, higher proinflammatory cytokine, and C-reactive protein concentrations. Possible sources of ET in the systemic circulation are bacterial translocation from the gastrointestinal tract and iron supplementation, potentially leading to intestinal bacterial overgrowth. Sevelamer is a nonabsorbable hydrogel approved for use as a phosphate binder in HD patients. Reductions in serum ET concentrations in hemodialysis patients have been observed with sevelamer therapy in observational studies and the few published interventional studies. Reduction of ET concentrations was associated with concomitant reductions in TNFα, IL-6, and CRP and improvement in serum albumin in the majority of these small studies. Additional studies are needed to evaluate the potential effects of sevelamer treatment on nutritional status in chronic kidney disease (CKD patients with elevated ET.

  6. Endotoxin as a determinant of asthma and wheeze among rural dwelling children and adolescents: A case–control study

    Directory of Open Access Journals (Sweden)

    Lawson Joshua A

    2012-09-01

    Full Text Available Abstract Background The association between endotoxin exposure and asthma is complex and has been associated with rural living. We examined the relationship between domestic endotoxin and asthma or wheeze among rural school-aged children (6–18 years and assessed the interaction between endotoxin and other characteristics with these outcomes. Methods Between 2005 and 2007 we conducted a case–control study of children 6–18 years in the rural region of Humboldt, Canada. Cases (n = 102 reported doctor-diagnosed asthma or wheeze in the past year. Controls (n = 208 were randomly selected from children without asthma or wheeze. Data were collected to ascertain symptoms, asthma history and indoor environmental exposures (questionnaire, endotoxin (dust collection from the play area floor and child’s mattress, and tobacco smoke exposure (saliva collection. Statistical testing was completed using multiple logistic regression to account for potential confounders and to assess interaction between risk factors. A stratified analysis was also completed to examine the effect of personal history of allergy. Results Among children aged 6–12 years, mattress endotoxin concentration (EU/mg and load (EU/m2 were inversely associated with being a case [odds ratio (OR = 0.44, 95% confidence interval (CI = 0.20-0.98; and OR = 0.38, 95% CI = 0.20-0.75, respectively]. These associations were not observed in older children or with play area endotoxin. Conclusions Our results suggest that endotoxin exposure might be protective for asthma or wheeze. The protective effect is found in younger school-aged, non-allergic children. These results may help explain the inconsistencies in previous studies and suggest that the protective effects of endotoxin in the prevention of atopy and asthma or wheeze are most effective earlier in life.

  7. Endotoxin exposure assessment - measurement and characterization

    NARCIS (Netherlands)

    Spaan, S.

    2008-01-01

    Endotoxin, one of the specific agents in organic dust that cause health effects, is part of the cell wall of Gram-negative bacteria. Gram-negative bacteria are present on for instance the surfaces of plants and in animal feces, and their occurrence, growth and amplification is influenced by many

  8. Evaluation of penicylinders used in disinfectant testing: bacterial attachment and surface texture.

    Science.gov (United States)

    Cole, E C; Rutala, W A; Carson, J L

    1987-01-01

    Two possible deficiencies in the AOAC use-dilution method for registration of chemical disinfectants by the Environmental Protection Agency are examined: (1) the physical disparities among brands of penicylinders and (2) the variability of bacterial numbers on penicylinders depending upon test strain and penicylinder surface texture. Textural differences of 2 brands of stainless steel penicylinders, one brand of porcelain, and one brand of glass were assessed by scanning electron microscopy. A considerable variation in smoothness of both inner and outer surfaces of stainless steel and porcelain penicylinders was observed. Glass penicylinders were very smooth. Numbers of bacteria attached to a penicylinder were assessed by vortexing the penicylinders 30 s at No. 4 after using the AOAC method of bacterial inoculation and drying 40 min at 37 degrees C. With this methodology, stainless steel carriers retained the 3 AOAC-recommended bacterial test strains differentially: ca 10(7) for Pseudomonas aeruginosa, 5 X 10(6) for Staphylococcus aureus, and 10(6) for Salmonella choleraesuis; glass retained 10(6)-10(7) organisms of all 3 test strains; porcelain retained about that amount of S. aureus but 10(5)-10(6) P. aeruginosa and 10(3)-10(4) S. choleraesuis. These data suggest that disinfectants are not similarly challenged with the AOAC-recommended test bacteria and that an alternative method should be considered to ensure comparable numbers of bacteria on penicylinders.

  9. House Dust Endotoxin and Peripheral Leukocyte Counts: Results from Two Large Epidemiologic Studies.

    Science.gov (United States)

    Fessler, Michael B; Carnes, Megan U; Salo, Päivi M; Wilkerson, Jesse; Cohn, Richard D; King, Debra; Hoppin, Jane A; Sandler, Dale P; Travlos, Greg; London, Stephanie; Thorne, Peter; Zeldin, Darryl

    2017-05-31

    The peripheral leukocyte count is a biomarker of inflammation and is associated with human all-cause mortality. Although causes of acute leukocytosis are well-described, chronic environmental determinants of leukocyte number are less well understood. We investigated the relationship between house dust endotoxin concentration and peripheral leukocyte counts in human subjects. The endotoxin–leukocyte relationship was evaluated by linear regression in the National Health and Nutrition Examination Survey (NHANES) 2005–2006 (n=6,254) and the Agricultural Lung Health Study (ALHS; n=1,708). In the ALHS, we tested for a gene [Toll-like Receptor 4 ( TLR4 ), encoding the endotoxin receptor]-by-environment interaction in the endotoxin–leukocyte relationship using regression models with an interaction term. There is a statistically significant, positive association between endotoxin concentration and total leukocyte number [estimated change, 0.186×10 3 /μL (95% CI: 0.070, 0.301×10 3 /μL) per 10-fold change in endotoxin; p=0.004) in the NHANES. Similar positive associations were found for monocytes, lymphocytes, and neutrophils. Stratified analyses revealed possible effect modification by asthma and chronic obstructive pulmonary disease. We observed similar associations in the ALHS. For total leukocytes, there was suggestive evidence in the ALHS of a gene-by-environment interaction for minor allele carrier status at the TLR4 haplotype defined by rs4986790 and rs4986791 (interaction p=0.15). This is, to our knowledge, the first report of an association between house dust endotoxin and leukocyte count in a national survey. The finding was replicated in a farming population. Peripheral leukocyte count may be influenced by residential endotoxin exposure in diverse settings. https://doi.org/10.1289/EHP661.

  10. Metal ions potentiate microglia responsiveness to endotoxin.

    Science.gov (United States)

    Rachmawati, Dessy; Peferoen, Laura A N; Vogel, Daphne Y S; Alsalem, Inás W A; Amor, Sandra; Bontkes, Hetty J; von Blomberg, B Mary E; Scheper, Rik J; van Hoogstraten, Ingrid M W

    2016-02-15

    Oral metal exposure has been associated with diverse adverse reactions, including neurotoxicity. We showed previously that dentally applied metals activate dendritic cells (MoDC) via TLR4 (Ni, Co, Pd) and TLR3 (Au). It is still unknown whether the low levels of dental metals reaching the brain can trigger local innate cells or prime them to become more responsive. Here we tested whether dentally applied metals (Cr, Fe, Co, Ni, Cu, Zn, Au, Hg) activate primary human microglia in vitro and, as a model, monocytic THP-1-cells, in high non-toxic as well as near-physiological concentrations. In addition the effects of 'near-physiological' metal exposure on endotoxin (LPS) responsiveness of these cells were evaluated. IL-8 and IL-6 production after 24h was used as read out. In high, non-toxic concentrations all transition metals except Cr induced IL-8 and IL-6 production in microglia, with Ni and Co providing the strongest stimulation. When using near-physiological doses (up to 10× the normal plasma concentration), only Zn and Cu induced significant IL-8 production. Of note, the latter metals also markedly potentiated LPS responsiveness of microglia and THP-1 cells. In conclusion, transition metals activate microglia similar to MoDCs. In near-physiological concentrations Zn and Cu are the most effective mediators of innate immune activation. A clear synergism between innate responses to Zn/Cu and LPS was observed, shedding new light on the possible relation between oral metal exposure and neurotoxicity. Copyright © 2015. Published by Elsevier B.V.

  11. Diagnostic value of latex agglutination test in diagnosis of acute bacterial meningitis

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    Syeda Fasiha Mohammadi

    2013-01-01

    Full Text Available Objectives: To know the incidence of bacterial meningitis in children below five years of age. To compare conventional culture and antigen detection methods ( Latex agglutination test. Materials and Methods: 100 CSF samples of clinically suspected meningitis cases in children below 5 years of age were included. The samples were subjected to cell count, Gram stain, culture and LAT. The organisms isolated in the study were characterized according to standard procedures. Results: Of the 100 cases studied, 31 cases were diagnosed as ABM by Gram stain, culture and latex agglutination test as per WHO criteria. The hospital frequency of ABM was 1.7%. 15 (48.38 cases were culture positive. Gram stain was positive in 22(70.96 cases and LAT in 17(54.83 cases. Haemophilus influenzae was the most common causative agent of acute bacterial meningitis followed by S.pneumoniae. Case fatality rate was 45.16%.The sensitivity and specificity of LAT was 66.66% and 87.91% respectively. Conclusion : Bacterial meningitis is a medical emergency and early diagnosis and treatment is life saving and reduces chronic morbidity. LAT was more sensitive compared to conventional Gram stain and Culture technique in identifying the fastidious organisms like H.influenzae, S.pneumoniae and Group B Streptococcus. However, the combination of Gram stain, Culture and LAT proved to be more productive than any of the single tests alone.

  12. Small intestinal bacterial overgrowth in nonalcoholic steatohepatitis: association with toll-like receptor 4 expression and plasma levels of interleukin 8.

    LENUS (Irish Health Repository)

    Shanab, Ahmed Abu

    2011-05-01

    Experimental and clinical studies suggest an association between small intestinal bacterial overgrowth (SIBO) and nonalcoholic steatohepatitis (NASH). Liver injury and fibrosis could be related to exposure to bacterial products of intestinal origin and, most notably, endotoxin, including lipopolysaccharide (LPS).

  13. Endotoxin-induced inflammation disturbs melatonin secretion in ewe.

    Science.gov (United States)

    Herman, Andrzej Przemysław; Wojtulewicz, Karolina; Bochenek, Joanna; Krawczyńska, Agata; Antushevich, Hanna; Pawlina, Bartosz; Zielińska-Górska, Marlena; Herman, Anna; Romanowicz, Katarzyna; Tomaszewska-Zaremba, Dorota

    2017-12-01

    The study examined the effect of intravenous administration of bacterial endotoxin-lipopolysaccharide (LPS) -on the nocturnal secretion of melatonin and on the expression of enzymes of the melatonin biosynthetic pathway in the pineal gland of ewes, taking into account two different photoperiodic conditions: short-night (SN; n = 12) and long-night (LN; n = 12). In both experiments, animals (n = 12) were randomly divided into two groups: control (n = 6) and LPS-treated (n = 6) one. Two hours after sunset, animals received an injection of LPS or saline. Blood samples were collected starting one hour after sunset and continuing for 3 hours after the treatment. The ewes were euthanized 3 hours after LPS/saline treatment. The concentration of hormones in plasma was assayed by radioimmunoassay. In the pineal gland, the content of serotonin and its metabolite was determined by HPLC; whereas the expression of examined genes and protein was assayed using real-time polymerase chain reaction and Western Blot, respectively. Endotoxin administration lowered (pewes from SN photoperiod only in the third hour after the injection. Inflammation more substantially suppressed biosynthesis of melatonin in ewes from SN photoperiod, which were also characterised by lower (pewes subjected to SN photoperiod, LPS reduced (p<0.05) serotonin content and the expression of melatonin biosynthetic pathway enzymes, such as tryptophan hydroxylase and arylalkylamine-N-acetyltransferase. Pineal activity may be disturbed by circulating LPS and proinflammatory cytokines because the expression of mRNAs encoding their corresponding receptors was determined in this gland. The present study showed that peripheral inflammation reduces the secretion of melatonin, but this effect may be influenced by the photoperiod.

  14. Sex differences in the pro-inflammatory cytokine response to endotoxin unfold in vivo but not ex vivo in healthy humans.

    Science.gov (United States)

    Wegner, Alexander; Benson, Sven; Rebernik, Laura; Spreitzer, Ingo; Jäger, Marcus; Schedlowski, Manfred; Elsenbruch, Sigrid; Engler, Harald

    2017-07-01

    Clinical data indicate that inflammatory responses differ across sexes, but the mechanisms remain elusive. Herein, we assessed in vivo and ex vivo cytokine responses to bacterial endotoxin in healthy men and women to elucidate the role of systemic and cellular factors underlying sex differences in inflammatory responses. Participants received an i.v. injection of low-dose endotoxin (0.4 ng/kg body mass), and plasma TNF-α and IL-6 responses were analyzed over a period of 6 h. In parallel, ex vivo cytokine production was measured in endotoxin-stimulated blood samples obtained immediately before in vivo endotoxin administration. As glucocorticoids (GCs) play an important role in the negative feedback regulation of the inflammatory response, we additionally analyzed plasma cortisol concentrations and ex vivo GC sensitivity of cytokine production. Results revealed greater in vivo pro-inflammatory responses in women compared with men, with significantly higher increases in plasma TNF-α and IL-6 concentrations. In addition, the endotoxin-induced rise in plasma cortisol was more pronounced in women. In contrast, no sex differences in ex vivo cytokine production and GC sensitivity were observed. Together, these findings demonstrate major differences in in vivo and ex vivo responses to endotoxin and underscore the importance of systemic factors underlying sex differences in the inflammatory response.

  15. Direct molecular testing to assess the incidence of meningococcal and other bacterial causes of meningitis among persons reported with unspecified bacterial meningitis.

    Science.gov (United States)

    Ramautar, Arianne E; Halse, Tanya A; Arakaki, Lola; Antwi, Mike; Del Rosso, Paula; Dorsinville, Marie; Nazarian, Elizabeth; Steiner-Sichel, Linda; Lee, Lillian; Dickinson, Michelle; Wroblewski, Danielle; Dumas, Nellie; Musser, Kimberlee; Isaac, Beth; Rakeman, Jennifer; Weiss, Don

    2015-11-01

    Confirmed and probable cases of invasive Neisseria meningitidis (Nm) infection are reportable in New York City. We conducted a study to identify Nm among culture-negative reports of bacterial and viral meningitis. During the study period, 262 reports of suspected meningitis were eligible. Cerebrospinal fluid (CSF) specimens from 138 patients were obtained for testing. No Nm cases were detected. Results from real-time polymerase chain reaction and 16S on CSF specimens were concordant with hospital microbiology findings in 80%; however, other pathogenic organisms were detected in 14 culture-negative specimens. New York City's surveillance system appears to be effective at capturing cases of Nm meningitis. Nucleic acid testing is useful for detecting the presence of bacterial DNA when antibiotic therapy precedes lumbar puncture or bacterial cultures are negative. It remains unanswered whether culture-negative cases of Nm bacteremia are being missed by reportable disease surveillance. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Bacterial Cytological Profiling (BCP as a Rapid and Accurate Antimicrobial Susceptibility Testing Method for Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    D.T. Quach

    2016-02-01

    Full Text Available Successful treatment of bacterial infections requires the timely administration of appropriate antimicrobial therapy. The failure to initiate the correct therapy in a timely fashion results in poor clinical outcomes, longer hospital stays, and higher medical costs. Current approaches to antibiotic susceptibility testing of cultured pathogens have key limitations ranging from long run times to dependence on prior knowledge of genetic mechanisms of resistance. We have developed a rapid antimicrobial susceptibility assay for Staphylococcus aureus based on bacterial cytological profiling (BCP, which uses quantitative fluorescence microscopy to measure antibiotic induced changes in cellular architecture. BCP discriminated between methicillin-susceptible (MSSA and -resistant (MRSA clinical isolates of S. aureus (n = 71 within 1–2 h with 100% accuracy. Similarly, BCP correctly distinguished daptomycin susceptible (DS from daptomycin non-susceptible (DNS S. aureus strains (n = 20 within 30 min. Among MRSA isolates, BCP further identified two classes of strains that differ in their susceptibility to specific combinations of beta-lactam antibiotics. BCP provides a rapid and flexible alternative to gene-based susceptibility testing methods for S. aureus, and should be readily adaptable to different antibiotics and bacterial species as new mechanisms of resistance or multidrug-resistant pathogens evolve and appear in mainstream clinical practice.

  17. Quantifying Dustiness, Specific Allergens, and Endotoxin in Bulk Soya Imports

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    Howard J. Mason

    2017-11-01

    Full Text Available Soya is an important bulk agricultural product often transported by sea as chipped beans and/or the bean husks after pelletisation. There are proven allergens in both forms. Bulk handling of soya imports can generate air pollution containing dust, allergens, and pyrogens, posing health risks to dockside workers and surrounding populations. Using an International Organization for Standardization (ISO standardised rotating drum dustiness test in seven imported soya bulks, we compared the generated levels of dust and two major soya allergens in three particle sizes related to respiratory health. Extractable levels of allergen and endotoxin from the bulks showed 30–60 fold differences, with levels of one allergen (hydrophobic seed protein and endotoxin higher in husk. The generated levels of dust and allergens in the three particle sizes also showed very wide variations between bulks, with aerolysed levels of allergen influenced by both the inherent dustiness and the extractable allergen in each bulk. Percentage allergen aerolysed from pelletized husk—often assumed to be of low dustiness—after transportation was not lower than that from chipped beans. Thus, not all soya bulks pose the same inhalation health risk and reinforces the importance of controlling dust generation from handling all soya bulk to as low as reasonably practicable.

  18. Geographical variation and the determinants of domestic endotoxin levels in mattress dust in Europe

    NARCIS (Netherlands)

    Chen, C.M.; Thiering, E.; Doekes, G.|info:eu-repo/dai/nl/070079803; Zock, J.P.|info:eu-repo/dai/nl/095184309; Bakolis, I.; Norbäck, D.; Sunyer, J.; Villani, S.; Verlato, G.; Täubel, M.; Jarvis, D.

    2012-01-01

    Endotoxin exposures have manifold effects on human health. The geographical variation and determinants of domestic endotoxin levels in Europe have not yet been extensively described. To investigate the geographical variation and determinants of domestic endotoxin concentrations in mattress dust in

  19. Effects of immune supplementation and immune challenge on bacterial assemblages in the avian cloaca

    NARCIS (Netherlands)

    Matson, Kevin D.; Versteegh, Maaike A.; van der Velde, Marco; Tieleman, B. Irene

    Relationships between avian physiology and bacterial assemblages in the cloaca are poorly understood. We used molecular techniques to analyze cloacal swabs from pigeons that were subjected to two immunological manipulations: lysozyme supplementation and endotoxin challenge. From the swabs, we

  20. Differential effects of air conditioning type on residential endotoxin levels in a semi-arid climate.

    Science.gov (United States)

    Johnston, J D; Kruman, B A; Nelson, M C; Merrill, R M; Graul, R J; Hoybjerg, T G; Tuttle, S C; Myers, S J; Cook, R B; Weber, K S

    2017-09-01

    Residential endotoxin exposure is associated with protective and pathogenic health outcomes. Evaporative coolers, an energy-efficient type of air conditioner used in dry climates, are a potential source of indoor endotoxins; however, this association is largely unstudied. We collected settled dust biannually from four locations in homes with evaporative coolers (n=18) and central air conditioners (n=22) in Utah County, Utah (USA), during winter (Jan-Apr) and summer (Aug-Sept), 2014. Dust samples (n=281) were analyzed by the Limulus amebocyte lysate test. Housing factors were measured by survey, and indoor temperature and relative humidity measures were collected during both seasons. Endotoxin concentrations (EU/mg) were significantly higher in homes with evaporative coolers from mattress and bedroom floor samples during both seasons. Endotoxin surface loads (EU/m 2 ) were significantly higher in homes with evaporative coolers from mattress and bedroom floor samples during both seasons and in upholstered furniture during winter. For the nine significant season-by-location comparisons, EU/mg and EU/m 2 were approximately three to six times greater in homes using evaporative coolers. A plausible explanation for these findings is that evaporative coolers serve as a reservoir and distribution system for Gram-negative bacteria or their cell wall components in homes. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Workplace Determinants of Endotoxin Exposure in Dental Healthcare Facilities in South Africa

    Science.gov (United States)

    Singh, Tanusha S.; Bello, Braimoh; Mabe, Onnicah D.; Renton, Kevin; Jeebhay, Mohamed F.

    2010-01-01

    Objectives: Aerosols generated during dental procedures have been reported to contain endotoxin as a result of bacterial contamination of dental unit water lines. This study investigated the determinants of airborne endotoxin exposure in dental healthcare settings. Methods: The study population included dental personnel (n = 454) from five academic dental institutions in South Africa. Personal air samples (n = 413) in various dental jobs and water samples (n = 403) from dental handpieces and basin taps were collected. The chromogenic-1000 limulus amebocyte lysate assay was used to determine endotoxin levels. Exposure metrics were developed on the basis of individually measured exposures and average levels within each job category. Analysis of variance and multivariate linear regression models were constructed to ascertain the determinants of exposure in the dental group. Results: There was a 2-fold variation in personal airborne endotoxin from the least exposed (administration) to the most exposed (laboratory) jobs (geometric mean levels: 2.38 versus 5.63 EU m−3). Three percent of personal samples were above DECOS recommended exposure limit (50 EU m−3). In the univariate linear models, the age of the dental units explained the most variability observed in the personal air samples (R2 = 0.20, P < 0.001), followed by the season of the year (R2 = 0.11, P < 0.001). Other variables such as institution and total number of dental units per institution also explained a modest degree of variability. A multivariate model explaining the greatest variability (adjusted R2 = 0.40, P < 0.001) included: the age of institution buildings, total number of dental units per institution, ambient temperature, ambient air velocity, endotoxin levels in water, job category (staff versus students), dental unit model type and age of dental unit. Conclusions: Apart from job type, dental unit characteristics are important predictors of airborne endotoxin

  2. Endotoxin-induced reduction of beta-adrenergic binding sites on splenic lymphocytes in vivo and in vitro : its modulation by anterior hypothalamic lesions

    NARCIS (Netherlands)

    Van Oosterhout, A J; Van Heuven-Nolsen, D; Thijssen, J H; Nijkamp, F P; de Boer, S.F.

    1989-01-01

    Bacterial endotoxin induced a 38% decrease in the number of beta-adrenergic binding sites (Bmax) on splenic lymphocytes, four days after intraperitoneal administration to guinea pigs. No change in the affinity (Kd) for [125-I]-cyanopindolol ([125-I]-CYP) binding was observed. Incubation of guinea

  3. Abnormal breath tests to lactose, fructose and sorbitol in irritable bowel syndrome may be explained by small intestinal bacterial overgrowth.

    Science.gov (United States)

    Nucera, G; Gabrielli, M; Lupascu, A; Lauritano, E C; Santoliquido, A; Cremonini, F; Cammarota, G; Tondi, P; Pola, P; Gasbarrini, G; Gasbarrini, A

    2005-06-01

    Small intestinal bacterial overgrowth and sugar malabsorption (lactose, fructose, sorbitol) may play a role in irritable bowel syndrome. The lactulose breath test is a reliable and non-invasive test for the diagnosis of small intestinal bacterial overgrowth. The lactose, fructose and sorbitol hydrogen breath tests are widely used to detect specific sugar malabsorption. To assess the extent to which small intestinal bacterial overgrowth may influence the results of hydrogen sugar breath tests in irritable bowel syndrome patients. We enrolled 98 consecutive irritable bowel syndrome patients. All subjects underwent hydrogen lactulose, lactose, fructose and sorbitol hydrogen breath tests. Small intestinal bacterial overgrowth patients were treated with 1-week course of antibiotics. All tests were repeated 1 month after the end of therapy. A positive lactulose breath test was found in 64 of 98 (65%) subjects; these small intestinal bacterial overgrowth patients showed a significantly higher prevalence of positivity to the lactose breath test (P fructose breath test (P fructose and sorbitol breath tests positivity (17% vs. 100%, 3% vs. 62%, and 10% vs. 71% respectively: P malabsorption misdiagnosis.

  4. Evaluation of leukocyte esterase and nitrite strip tests to detect spontaneous bacterial peritonitis in cirrhotic patients.

    Science.gov (United States)

    Torun, Serkan; Dolar, Enver; Yilmaz, Yusuf; Keskin, Murat; Kiyici, Murat; Sinirtas, Melda; Sarandol, Emre; Gurel, Selim; Nak, Selim-Giray; Gulten, Macit

    2007-12-07

    To investigate the diagnostic efficacy of leukocyte esterase and nitrite reagent strips for bedside diagnosis of spontaneous bacterial peritonitis (SBP). A total of 63 consecutive patients with cirrhotic ascites (38 male, 25 female) tested between April 2005 and July 2006 were included in the study. Bedside reagent strip testing was performed on ascitic fluid and the results compared to manual cell counting and ascitic fluid culture. SBP was defined as having a polymorphonuclear ascites count of >or= 250/mm(3). Fifteen samples showed SBP. The sensitivity, specificity, positive and negative predictive values of the leukocyte esterase reagent strips were; 93%, 100%, 100%, and 98%, respectively. The sensitivity, specificity, positive and negative predictive value of the nitrite reagent strips were 13%, 93%, 40%, and 77%, respectively. The combination of leukocyte esterase and nitrite reagents strips did not yield statistically significant effects on diagnostic accuracy. Leukocyte esterase reagent strips may provide a rapid, bedside diagnostic test for SBP.

  5. Effects of aging on endotoxin tolerance induced by lipopolysaccharides derived from Porphyromonas gingivalis and Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Ying Sun

    Full Text Available Periodontitis is a bacterially induced chronic inflammatory disease. Exposure of the host to periodontal pathogens and their virulence factors induces a state of hyporesponsiveness to subsequent stimulations, termed endotoxin tolerance. Aging has a profound effect on immune response to bacteria challenge. The aim of this study was to explore the effects of aging on endotoxin tolerance induced by Porphyromonas gingivalis (P. gingivalis lipopolysaccharide (LPS and Escherichia coli (E. coli LPS in murine peritoneal macrophages.We studied the cytokine production (TNF-α and IL-10 and Toll-like receptor 2, 4 (TLR2, 4 gene and protein expressions in peritoneal macrophages from young (2-month-old and middle-aged (12-month-old ICR mice following single or repeated P. gingivalis LPS or E. coli LPS stimulation. Pretreatment of peritoneal macrophages with P. gingivalis LPS or E. coli LPS resulted in a reduction in TNF-α production and an increase in IL-10 production upon secondary stimulation (p<0.05, and the markedly lower levels of TNF-α and higher levels of IL-10 were observed in macrophages from young mice compared with those from middle-aged mice (p<0.05. In addition, LPS restimulations also led to the significantly lower expression levels of TLR2, 4 mRNA and protein in macrophages from young mice (p<0.05.Repeated LPS stimulations triggered endotoxin tolerance in peritoneal macrophages and the ability to develop tolerance in young mice was more excellent. The impaired ability to develop endotoxin tolerance resulted from aging might be related to TLR2, 4 and might lead to the incontrollable periodontal inflammation in older adults.

  6. Novel endotoxin-sequestering compounds with terephthalaldehyde-bis-guanylhydrazone scaffolds.

    Science.gov (United States)

    Khownium, Kriangsak; Wood, Stewart J; Miller, Kelly A; Balakrishna, Rajalakshmi; Nguyen, Thuan B; Kimbrell, Matthew R; Georg, Gunda I; David, Sunil A

    2006-03-01

    We have shown that lipopolyamines bind to the lipid A moiety of lipopolysaccharide, a constituent of Gram-negative bacterial membranes, and neutralize its toxicity in animal models of endotoxic shock. In an effort to identify non-polyamine scaffolds with similar endotoxin-recognizing features, we had observed an unusually high frequency of hits containing guanylhydrazone scaffolds in high-throughput screens. We now describe the syntheses and preliminary structure-activity relationships in a homologous series of bis-guanylhydrazone compounds decorated with hydrophobic functionalities. These first-generation compounds bind and neutralize lipopolysaccharide with a potency comparable to that of polymyxin B, a peptide antibiotic known to sequester LPS.

  7. Multiple linear regression and artificial neural networks for delta-endotoxin and protease yields modelling of Bacillus thuringiensis.

    Science.gov (United States)

    Ennouri, Karim; Ben Ayed, Rayda; Triki, Mohamed Ali; Ottaviani, Ennio; Mazzarello, Maura; Hertelli, Fathi; Zouari, Nabil

    2017-07-01

    The aim of the present work was to develop a model that supplies accurate predictions of the yields of delta-endotoxins and proteases produced by B. thuringiensis var. kurstaki HD-1. Using available medium ingredients as variables, a mathematical method, based on Plackett-Burman design (PB), was employed to analyze and compare data generated by the Bootstrap method and processed by multiple linear regressions (MLR) and artificial neural networks (ANN) including multilayer perceptron (MLP) and radial basis function (RBF) models. The predictive ability of these models was evaluated by comparison of output data through the determination of coefficient (R 2 ) and mean square error (MSE) values. The results demonstrate that the prediction of the yields of delta-endotoxin and protease was more accurate by ANN technique (87 and 89% for delta-endotoxin and protease determination coefficients, respectively) when compared with MLR method (73.1 and 77.2% for delta-endotoxin and protease determination coefficients, respectively), suggesting that the proposed ANNs, especially MLP, is a suitable new approach for determining yields of bacterial products that allow us to make more appropriate predictions in a shorter time and with less engineering effort.

  8. Structural and functional features of self-assembling protein nanoparticles produced in endotoxin-free Escherichia coli.

    Science.gov (United States)

    Rueda, Fabián; Céspedes, María Virtudes; Sánchez-Chardi, Alejandro; Seras-Franzoso, Joaquin; Pesarrodona, Mireia; Ferrer-Miralles, Neus; Vázquez, Esther; Rinas, Ursula; Unzueta, Ugutz; Mamat, Uwe; Mangues, Ramón; García-Fruitós, Elena; Villaverde, Antonio

    2016-04-08

    Production of recombinant drugs in process-friendly endotoxin-free bacterial factories targets to a lessened complexity of the purification process combined with minimized biological hazards during product application. The development of nanostructured recombinant materials in innovative nanomedical activities expands such a need beyond plain functional polypeptides to complex protein assemblies. While Escherichia coli has been recently modified for the production of endotoxin-free proteins, no data has been so far recorded regarding how the system performs in the fabrication of smart nanostructured materials. We have here explored the nanoarchitecture and in vitro and in vivo functionalities of CXCR4-targeted, self-assembling protein nanoparticles intended for intracellular delivery of drugs and imaging agents in colorectal cancer. Interestingly, endotoxin-free materials exhibit a distinguishable architecture and altered size and target cell penetrability than counterparts produced in conventional E. coli strains. These variant nanoparticles show an eventual proper biodistribution and highly specific and exclusive accumulation in tumor upon administration in colorectal cancer mice models, indicating a convenient display and function of the tumor homing peptides and high particle stability under physiological conditions. The observations made here support the emerging endotoxin-free E. coli system as a robust protein material producer but are also indicative of a particular conformational status and organization of either building blocks or oligomers. This appears to be promoted by multifactorial stress-inducing conditions upon engineering of the E. coli cell envelope, which impacts on the protein quality control of the cell factory.

  9. Crystal structure of an endotoxin-neutralizing protein from the horseshoe crab, Limulus anti-LPS factor, at 1.5 A resolution.

    OpenAIRE

    Hoess, A; Watson, S; Siber, G R; Liddington, R

    1993-01-01

    Lipopolysaccharide (LPS), or endotoxin, is the major mediator of septic shock, a serious complication of Gram-negative bacterial infections in humans. Molecules that bind LPS and neutralize its biological effects or enhance its clearance could have important clinical applications. Limulus anti-LPS factor (LALF) binds LPS tightly, and, in animal models, reduces mortality when administered before or after LPS challenge or bacterial infection. Here we present the high resolution structure of a r...

  10. The redistribution of granulocytes following E. coli endotoxin induced sepsis

    DEFF Research Database (Denmark)

    Toft, P; Lillevang, S T; Tønnesen, Else Kirstine

    1994-01-01

    Infusion of endotoxin elicits granulocytopenia followed by increased numbers of granulocytes in peripheral blood. The purpose of this study was to investigate the redistribution and sequestration of granulocytes in the tissues following E. coli endotoxin induced sepsis. From 16 rabbits granulocytes...

  11. Analysis of interleukin-6 in endotoxin-induced uveitis

    NARCIS (Netherlands)

    Hoekzema, R.; Murray, P. I.; van Haren, M. A.; Helle, M.; Kijlstra, A.

    1991-01-01

    The mechanisms underlying the induction of intraocular inflammation in the rat model of endotoxin-induced uveitis (EIU) and the subsequent development of tolerance after repeated endotoxin injections are poorly understood. Interleukin-6 (IL-6) was measured in the aqueous humor and serum of Lewis

  12. Performance of BVBlue Rapid Test in Detecting Bacterial Vaginosis among Women in Mysore, India

    Directory of Open Access Journals (Sweden)

    Purnima Madhivanan

    2014-01-01

    Full Text Available Bacterial vaginosis (BV is the most common cause of abnormal vaginal discharge in reproductive age women. It is associated with increased susceptibility to HIV/STI and adverse birth outcomes. Diagnosis of BV in resource-poor settings like India is challenging. With little laboratory infrastructure there is a need for objective point-of-care diagnostic tests. Vaginal swabs were collected from women 18 years and older, with a vaginal pH > 4.5 attending a reproductive health clinic. BV was diagnosed with Amsel’s criteria, Nugent scores, and the OSOM BVBlue test. Study personnel were blinded to test results. There were 347 participants enrolled between August 2009 and January 2010. BV prevalence was 45.1% (95% confidence interval (CI: 41.5%–52.8% according to Nugent score. When compared with Nugent score, the sensitivity, specificity, positive predictive value, negative predictive value for Amsel’s criteria and BVBlue were 61.9%, 88.3%, 81.5%, 73.7% and 38.1%, 92.7%, 82.1%, 63.9%, respectively. Combined with a “whiff” test, the performance of BVBlue increased sensitivity to 64.4% and negative predictive value to 73.8%. Despite the good specificity, poor sensitivity limits the usefulness of the BVBlue as a screening test in this population. There is a need to examine the usefulness of this test in other Indian populations.

  13. The redistribution of granulocytes following E. coli endotoxin induced sepsis

    DEFF Research Database (Denmark)

    Toft, P; Lillevang, S T; Tønnesen, Else Kirstine

    1994-01-01

    Infusion of endotoxin elicits granulocytopenia followed by increased numbers of granulocytes in peripheral blood. The purpose of this study was to investigate the redistribution and sequestration of granulocytes in the tissues following E. coli endotoxin induced sepsis. From 16 rabbits granulocytes...... were isolated, labelled with Indium and reinjected intravenously. Eight rabbits received an infusion of E. coli endotoxin 2 micrograms kg-1 while eight received isotonic saline. The redistribution of granulocytes was imaged with a gamma camera and calculated with a connected computer before and 2 and 6...... hours after infusion of endotoxin or saline. Serum cortisol and interleukin-1 beta were measured. In another seven rabbits, respiratory burst activity and degranulation of granulocytes were measured prior to and from 5 min to 6 hours after infusion of E. coli endotoxin 2 micrograms kg-1 BW. Following...

  14. Endotoxin and CD14 in the progression of biliary atresia

    Directory of Open Access Journals (Sweden)

    Chen Ching-Mei

    2010-12-01

    Full Text Available Abstract Background Biliary atresia (BA is a typical cholestatic neonatal disease, characterized by obliteration of intra- and/or extra-hepatic bile ducts. However, the mechanisms contributing to the pathogenesis of BA remain uncertain. Because of decreased bile flow, infectious complications and damaging endotoxemia occur frequently in patients with BA. The aim of this study was to investigate endotoxin levels in patients with BA and the relation of these levels with the expression of the endotoxin receptor, CD14. Methods The plasma levels of endotoxin and soluble CD14 were measured with a pyrochrome Limulus amebocyte lysate assay and enzyme-linked immunosorbent assay in patients with early-stage BA when they received the Kasai procedure (KP, in patients who were jaundice-free post-KP and followed-up at the outpatient department, in patients with late-stage BA when they received liver transplantation, and in patients with choledochal cysts. The correlation of CD14 expression with endotoxin levels in rats following common bile duct ligation was investigated. Results The results demonstrated a significantly higher hepatic CD14 mRNA and soluble CD14 plasma levels in patients with early-stage BA relative to those with late-stage BA. However, plasma endotoxin levels were significantly higher in both the early and late stages of BA relative to controls. In rat model, the results demonstrated that both endotoxin and CD14 levels were significantly increased in liver tissues of rats following bile duct ligation. Conclusions The significant increase in plasma endotoxin and soluble CD14 levels during BA implies a possible involvement of endotoxin stimulated CD14 production by hepatocytes in the early stage of BA for removal of endotoxin; whereas, endotoxin signaling likely induced liver injury and impaired soluble CD14 synthesis in the late stages of BA.

  15. Molecular leakage at implant-abutment connection--in vitro investigation of tightness of internal conical implant-abutment connections against endotoxin penetration.

    Science.gov (United States)

    Harder, Sönke; Dimaczek, Birka; Açil, Yaha; Terheyden, Hendrik; Freitag-Wolf, Sandra; Kern, Matthias

    2010-08-01

    Microleakage has been discussed as a major contributing factor for inflammatory reactions at the implant-abutment connection. In previous studies, the tightness against corpuscular bodies (viable bacteria) has been successfully investigated under static and dynamic conditions. The aim of this study was to investigate the tightness against endotoxins of two implant systems (AstraTech and Ankylos) with conical internal connections under static conditions. The inner parts of eight implants of each system were inoculated with endotoxin. Implants were screwed together with the respective abutments and stored under isostatic conditions in a supernatant of pyrogen-free water for 168 h. Supernatant samples were taken after 5 min, 24 h, 72 h, and 168 h, and endotoxin contamination was determined by the amebocyte-lysate test. Only one implant in the AstraTech group showed no sign of endotoxin contamination after 168 h, while the other implants showed contamination after varying storage times, respectively. The implants in the Ankylos group showed endotoxin contamination after only 5 min of storage in the supernatant solution. The tested internal conical implant-abutment connections appear to be unable to prevent endotoxin leakage. In average, Astra implants showed a higher tightness than Ankylos implants.

  16. Intestinal Dysbiosis, Barrier Dysfunction, and Bacterial Translocation Account for CKD-Related Systemic Inflammation.

    Science.gov (United States)

    Andersen, Kirstin; Kesper, Marie Sophie; Marschner, Julian A; Konrad, Lukas; Ryu, Mi; Kumar Vr, Santhosh; Kulkarni, Onkar P; Mulay, Shrikant R; Romoli, Simone; Demleitner, Jana; Schiller, Patrick; Dietrich, Alexander; Müller, Susanna; Gross, Oliver; Ruscheweyh, Hans-Joachim; Huson, Daniel H; Stecher, Bärbel; Anders, Hans-Joachim

    2017-01-01

    CKD associates with systemic inflammation, but the underlying cause is unknown. Here, we investigated the involvement of intestinal microbiota. We report that collagen type 4 α3-deficient mice with Alport syndrome-related progressive CKD displayed systemic inflammation, including increased plasma levels of pentraxin-2 and activated antigen-presenting cells, CD4 and CD8 T cells, and Th17- or IFNγ-producing T cells in the spleen as well as regulatory T cell suppression. CKD-related systemic inflammation in these mice associated with intestinal dysbiosis of proteobacterial blooms, translocation of living bacteria across the intestinal barrier into the liver, and increased serum levels of bacterial endotoxin. Uremia did not affect secretory IgA release into the ileum lumen or mucosal leukocyte subsets. To test for causation between dysbiosis and systemic inflammation in CKD, we eradicated facultative anaerobic microbiota with antibiotics. This eradication prevented bacterial translocation, significantly reduced serum endotoxin levels, and fully reversed all markers of systemic inflammation to the level of nonuremic controls. Therefore, we conclude that uremia associates with intestinal dysbiosis, intestinal barrier dysfunction, and bacterial translocation, which trigger the state of persistent systemic inflammation in CKD. Uremic dysbiosis and intestinal barrier dysfunction may be novel therapeutic targets for intervention to suppress CKD-related systemic inflammation and its consequences. Copyright © 2016 by the American Society of Nephrology.

  17. Rapid bacterial antibiotic susceptibility test based on simple surface-enhanced Raman spectroscopic biomarkers

    Science.gov (United States)

    Liu, Chia-Ying; Han, Yin-Yi; Shih, Po-Han; Lian, Wei-Nan; Wang, Huai-Hsien; Lin, Chi-Hung; Hsueh, Po-Ren; Wang, Juen-Kai; Wang, Yuh-Lin

    2016-03-01

    Rapid bacterial antibiotic susceptibility test (AST) and minimum inhibitory concentration (MIC) measurement are important to help reduce the widespread misuse of antibiotics and alleviate the growing drug-resistance problem. We discovered that, when a susceptible strain of Staphylococcus aureus or Escherichia coli is exposed to an antibiotic, the intensity of specific biomarkers in its surface-enhanced Raman scattering (SERS) spectra drops evidently in two hours. The discovery has been exploited for rapid AST and MIC determination of methicillin-susceptible S. aureus and wild-type E. coli as well as clinical isolates. The results obtained by this SERS-AST method were consistent with that by the standard incubation-based method, indicating its high potential to supplement or replace existing time-consuming methods and help mitigate the challenge of drug resistance in clinical microbiology.

  18. EVALUATION OF LEUKOCYTE ESTERASE REAGENT STRIPS TEST IN THE DIAGNOSIS OF SPONTANEOUS BACTERIAL PERITONITIS IN CHILDREN WITH CIRRHOSIS

    Directory of Open Access Journals (Sweden)

    Naser HONAR

    2015-09-01

    Full Text Available BackgroundSpontaneous bacterial peritonitis is defined as an ascetic fluid infection without an evident intra-abdominal surgically treatable source. Spontaneous bacterial peritonitis is one of the severe complications in patients with cirrhosis and ascites. Without early antibiotic treatment, this complication is associated with high mortality rate; therefore, early diagnosis and treatment of spontaneous bacterial peritonitis is necessary for survival. Leukocyte esterase reagent can rapidly diagnose the spontaneous bacterial peritonitis.ObjectiveThis study aimed to find out the diagnostic accuracy of leukocyte esterase dipstick test for the diagnosis of spontaneous bacterial peritonitis.MethodsA single centered hospital-based cross-sectional study was conducted during July 2013 to August 2014 on children with cirrhotic liver disease and ascites who were admitted in the Department of Pediatric Gastroenterology in Nemazee Hospital affiliated to Shiraz University of Medical Sciences (Iran. All patients underwent abdominal paracentesis, and the ascitic fluid was processed for cell count, leukocyte esterase reagent strip test (Combiscreen SL10 and culture. Spontaneous bacterial peritonitis was defined as having a polymorphonuclear count (PMN ≥250/m3 in ascitic fluid. Sensitivity, specificity, positive predictive value and negative predictive value of leukocyte esterase test were calculated according to the formula.ResultsTotally, 150 ascitic fluid sample of cirrhotic male patients (53.2% and their mean age (4.33±1.88 years were analyzed. Biliary atresia (n=44, 29.4% and idiopathic neonatal hepatitis (n=29, 19.3% were the most frequent etiology of cirrhosis. Also, abdominal pain (68.6% and distension (64% were the most common presenting complaint. Of all cases, 41patients (27.35% were diagnosed to have spontaneous bacterial peritonitis (PMN ≥250/mm3. Sensitivity and specificity of leukocyte esterase reagent test according to PMNs ≥250mm3 were

  19. [The protective properties of the endotoxin protein].

    Science.gov (United States)

    Levenson, V I; Belkin, Z P; Egorova, T P

    1991-08-01

    The isolation and properties of endotoxin protein, or lipid A-associated protein (LAP), from Shigella sonnei were described earlier (Zh. mikrobiol. epidemiol. immunobiol., 1991, No. 4, pp. 11-17, and No. 7). In this report the data on its protective activity are presented. In experiments on mice one nanogram of LAP injected i. v. protected 50% of the animals against i. p. challenge with 40 LD50 of virulent S. sonnei. Guinea pigs injected s. c. with 10 micrograms of LAP were protected against local (keratoconjunctival) challenge with S. sonnei, the efficiency of immunization being 58%. LAP preparations containing no detectable amounts of O-antigen (less than 0.003%) were found to have a protective effect. Hyperimmune anti-LAP rabbit serum prevented local infection when incubated with S. sonnei challenge inoculum before injection into guinea pigs. Both active and passive protection induced by LAP was specific since no effect was observed in animals challenged with Shigella flexneri. In the homologous system the protective effect of anti-LAP serum was abolished by the addition of protein-free LPS. These results are compatible with the hypothesis that the protective activity of LAP depends on the presence of minute amounts of O-antigen whose immunogenic effect is greatly amplified by the protein component of the natural endotoxin complex.

  20. Intestinal radiation syndrome: sepsis and endotoxin

    International Nuclear Information System (INIS)

    Geraci, J.P.; Jackson, K.L.; Mariano, M.S.

    1985-01-01

    Rats were whole-body irradiated with 8-MeV cyclotron-produced neutrons and 137 Cs γ rays to study the role of enteric bacteria and endotoxin in the intestinal radiation syndrome. Decrease in intestinal weight was used as an index of radiation-induced breakdown of the mucosa. Neutron and γ-ray doses that were sublethal for intestinal death resulted in a dose-dependent decrease in intestinal weight, reaching minimal values 2 to 3 days after exposure, followed by recovery within 5 days after irradiation. Neutron and photon doses that caused intestinal death resulted in greater mucosal breakdown with little or no evidence of mucosal recovery. The presence of fluid in the intestine and diarrhea, but not bacteremia or endotoxemia, were related to mucosal breakdown and recovery. Neither sepsis nor endotoxin could be detected in liver samples taken at autopsy from animals which died a short time earlier from intestinal injury. These results suggest that overt sepsis and endotoxemia do not play a significant role in the intestinal radiation syndrome

  1. Assessing the removal potential of soil-aquifer treatment system (soil column) for endotoxin.

    Science.gov (United States)

    Guizani, Mokhtar; Kato, Hideaki; Funamizu, Naoyuki

    2011-06-01

    Soil-aquifer treatment (SAT) of wastewater is an increasingly valued practice for replenishing aquifers due to ease of operation and low maintenance needs and therefore low cost. In this study, we investigated the fate of endotoxins through laboratory-scale SAT soil columns over a four month period. The effluent of rapid sand filtration was run through the columns under gravity flow conditions. Four SAT columns were packed with four different filter materials (fine sand, medium sand, coarse sand and very coarse sand). The effluent of rapid sand filtration (average dissolved organic carbon (DOC) = 4 mg l(-1) and average endotoxin concentration = 4 EU ml(-1)) was collected from a domestic wastewater treatment plant in Sapporo, Japan. DOC removal ranged from 12.5% to greater than 22.5% during the study, with DOC levels averaging 3.1 and 3.5 mg l(-1) for the SAT columns packed with different soils. Endotoxin transformation exhibited different profiles, depending on the time and soil type. Reduction in endotoxin concentration averaged 64.3% and was as high as 86.7% across the soil columns 1, 2, 3 and 4, respectively. While DOC removal was gradual, the reductions in endotoxin levels were rather rapid and most of the removal was achieved in the top layers. Soil with a larger grain size had lower efficiency in removing endotoxin. Tests were performed to evaluate the transformation of organic matter showing endotoxicity and to determine the mechanisms responsible for changes in the structural and size properties of dissolved organic matter (OM) during SAT. Dissolved OM was fractionated using Sep-Pack C18 Cartridges into hydrophobic and hydrophilic fractions. Dialysis tubes with different molecular weight cut-offs were used to perform size fractions of OM showing endotoxicity. Evaluation of the transformation of organic matter showing endotoxicity during SAT indicated that both hydrophobic and large molecules were reduced. Moreover, experimental findings showed that

  2. Activity of Bacillus thuringiensis D(delta)-endotoxins against codling moth (Cydia pomonella L.) larvae

    NARCIS (Netherlands)

    Boncheva, R.; Dukiandjiev, S.; Minkov, I.; Maagd, de R.A.; Naimov, S.

    2006-01-01

    Solubilized protoxins of nine Cry1 and one hybrid Cry1 ¿-endotoxin from Bacillus thuringiensis were tested for their activity against larvae of the codling moth (Cydia pomonella L). Cry1Da was the most toxic, followed by Cry1Ab, Cry1Ba, and Cry1Ac, while Cry1Aa, Cry1Fa, Cry1Ia, and SN19 were still

  3. Immunization of cows with novel core glycolipid vaccine induces anti-endotoxin antibodies in bovine colostrum.

    Science.gov (United States)

    Cross, Alan S; Karreman, Hubert J; Zhang, Lei; Rosenberg, Zeil; Opal, Steven M; Lees, Andrew

    2014-10-21

    Translocation of gut-derived Gram-negative bacterial (GNB) lipopolysaccharide (LPS, or endotoxin) is a source of systemic inflammation that exacerbates HIV, cardiovascular and gastrointestinal diseases and malnutrition. The oral administration of bovine colostrum (BC) reduces endotoxemia in patients with impaired gut barrier function. Consequently, BC enriched in antibodies to LPS may ameliorate endotoxemia-related morbidities. We developed a detoxified J5 LPS/group B meningococcal outer membrane protein (J5dLPS/OMP) vaccine that induces antibodies against a highly conserved core region of LPS and protects against heterologous GNB infection. We now examine the ability of this vaccine to elicit anti-core endotoxin antibodies in BC. Two cohorts of pregnant cows were immunized with this vaccine in combination with FICA (Cohort 1) or Emulsigen-D (Cohort 2) adjuvants. Antibody responses to the J5 core LPS antigen were measured in both serum and colostrum and compared to antibody levels elicited by a commercially available veterinary vaccine (J5 Bacterin) comprised of heat-killed Escherichia coli O111, J5 mutant bacteria, from which the J5 LPS was purified. The J5dLPS/OMP vaccine induced high titers of serum IgG antibody to J5 LPS in all seven cows. Both IgG and to a lesser extent IgA anti-J5 LPS antibodies were generated in the colostrum. The J5dLPS/OMP vaccine was significantly more immunogenic in mice than was the J5 Bacterin. BC enriched in anti-J5 LPS antibody reduced circulating endotoxin levels in neutropenic rats, a model of "leaky gut". The J5dLPS/OMP vaccine elicits high titers of serum anti-endotoxin antibodies in cows that is passed to the colostrum. This BC enriched in anti-core LPS antibodies has the potential to reduce endotoxemia and ameliorate endotoxin-related systemic inflammation in patients with impaired gut barrier function. Since this vaccine is significantly more immunogenic than the J5 Bacterin vaccine, this J5dLPS/OMP vaccine might prove to be

  4. Effects of endotoxin on mammary secretion of lactating cows

    International Nuclear Information System (INIS)

    Lengemann, F.W.; Pitzrick, M.

    1986-01-01

    The objectives were to describe the magnitude and time course of changes in milk pH, Na, K, lactose, and somatic cells and to determine if paracellular pathways were altered after infusion of Escherichia coli endotoxin (serotype 0128:AB12) to produce inflammation in one-half of the udder of the goat. Intramammary infusion of endotoxin increased pH, number of somatic cells, and Na and decreased K and lactose in milk. Sodium and number of somatic cells were increased by as little as .1μg of endotoxin; .25 μg produced changes in most of the other parameters; maximal effect was elicited by 1μg of endotoxin. The gland response peaked from 5 to 7 h after infusion of endotoxin with an increase in milk cellularity as the only significant effect noted in the control gland. Infusion of [ 14 C]lactose into the gland and [/sup 99m/Tc]albumin into the blood demonstrated that large molecules were more able to cross into and out of udder halves after endotoxin treatment. It is suggested that ion interchange rather than bulk flow across paracellular paths is responsible for changes. In addition, endotoxin appeared to reduce lactose secretion and synthesis

  5. Intestinal endotoxins as co-factors of liver injury in obstructive jaundice.

    Science.gov (United States)

    Mentes, B B; Tatlicioglu, E; Akyol, G; Uluoglu, O; Sultan, N; Yilmaz, E; Celebi, M; Taneri, F; Ferahkose, Z

    1996-01-01

    The concept of endotoxin-mediated rather than direct liver injury in biliary obstruction was investigated using the experimental rat model of bile duct ligation (BDL) and small bowel bacterial overgrowth (SBBO). Small identical doses of intravenous endotoxin (bacterial LPS) caused a significantly more severe liver injury in rats with BDL, compared with sham-operated rats, suggesting the possible contribution of LPS in this type of liver damage. BDL was then combined with surgically created jejunal self-filling blind loops, which resulted in SBBO. Plasma LPS level increased significantly, and once again a more severe liver injury, determined by liver histology and serum gamma-glutamyl transpeptidase levels, was observed compared with the control group of rats with BDL+self-emptying blind loops. The data presented suggest that small amounts of exogenous LPS and/or the ordinarily innocous amounts of LPS constantly absorbed from the intestinal tract may be critical in the hepatic damage caused by obstruction of the biliary tract.

  6. Hypo-responsiveness of interleukin-8 production in human embryonic epithelial intestine 407 cells independent of NF-κB pathway: New lessons from endotoxin and ribotoxic deoxynivalenol

    International Nuclear Information System (INIS)

    Moon, Yuseok; Yang, Hyun; Park, Seung-Hwan

    2008-01-01

    Mucosal epithelium senses external toxic insults and transmits the danger signals into the epithelial cells in order to activate a broad range of inflammatory responses. However, pre-exposure to the commensal endotoxins can induce inflammatory tolerance and maintain the homeostasis without excessive immune responses. We recently reported that ribotoxin deoxynivalenol (DON) and its derivatives elicited the pro-inflammatory response as the mucosal insults in human epithelial cells. Taking the knowledge into consideration, we tested the hypothesis that endotoxin pre-exposure can attenuate ribotoxin-induced epithelial interleukin-8 (IL-8) production via a tolerance mechanism. Pre-exposure to endotoxin repressed IL-8 release and its gene expression. However, inflammatory tolerance was not mediated by the attenuated NF-κB activation which has been generally recognized as the major mediator of LPS-mediated toll-like receptor (TLR) signaling pathway. Instead, pre-exposure to endotoxin was observed to trigger the delayed induction of peroxisome proliferator-activated receptor gamma (PPAR-γ) which contributed to the diminished IL-8 production in the human epithelial cells. Moreover, endogenous PPAR-γ agonist suppressed toxicant-mediated interleukin-8 production and IL-8 mRNA stability. Taken together, endotoxin induced hypo-production of pro-inflammatory cytokine IL-8 in the human epithelial cells, which was associated with the delayed activation of PPAR-γ expression by pre-existing endotoxin

  7. Usefulness of blood and cerebrospinal fluid laboratory testing to predict bacterial meningitis in the emergency department.

    Science.gov (United States)

    Julián-Jiménez, A; Morales-Casado, M I

    2016-07-25

    The classic clinical presentation of bacterial meningitis (BM) is observed in less than half of the cases in adults, and symptoms are less specific in children, the elderly or immunocompromised, and other chronic patients. The usual signs and symptoms do not provide optimal sensitivity and specificity for distinguishing possible BM from viral meningitis (VM), which may lead to a delay in the appropriate antimicrobial therapy. Society therefore stands to benefit from the development of effective, objective, and rapid tools able to predict and identify patients with BM. These tools include laboratory tests for blood and cerebrospinal fluid (CSF). The aim of this review is to summarise recently published scientific evidence in order to clarify existing controversies and compare the usefulness and diagnostic ability of the different parameters used to predict BM. Systematic search of the main bibliographic databases and platforms to identify articles published between January 2000 and January 2016. We selected 59 articles that meet the objectives of this review. CSF lactate, proportion of polymorphonuclear leukocytes, and CSF glucose, as well as serum procalcitonin (PCT), are the independent factors most predictive of bacterial aetiology. The model that combines serum PCT and CSF lactate achieves the highest predictive power for BM, with a sensitivity and specificity exceeding 99%. We should consider BM when CSF lactate >33 md/dL and/or PCT>0.25ng/mL. Copyright © 2016 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  8. A synthetic cyclic peptide derived from Limulus anti-lipopolysaccharide factor neutralizes endotoxin in vitro and in vivo.

    Science.gov (United States)

    Ren, Jian-Dong; Gu, Jin-Song; Gao, Hong-Fu; Xia, Pei-Yuan; Xiao, Guang-Xia

    2008-06-01

    Endotoxin, also known as lipopolysaccharide (LPS), is the major mediator of septic shock due to Gram-negative bacterial infections. Recently, much attention has been focused on cationic peptides which possess the potential to detoxify LPS. Limulus anti-LPS factor (LALF), a protein found in the horseshoe crab (Limulus polyphemus), has been proved with striking anti-LPS effects. We synthesized a cyclic peptide (CLP-19), and then investigated its bioactivity both in vitro and in vivo. The ability of CLP-19 to neutralize LPS in vitro was tested using a Limulus amebocyte lysate (LAL) assay and the LPS-binding affinity was measured with an affinity biosensor method. The synthetic peptide LALF31-52 (residues 31 to 52 of LALF) was used as the positive control peptide in this study. It was found that CLP-19 exhibited the significant activity to antagonize LPS without observable cytotoxicity effect on mouse macrophages. CLP-19 directly bound to LPS, and neutralized it in a dose-dependent manner in the LAL assay. Moreover, CLP-19 also showed the remarkable ability to protect mice from lethal LPS attack and to inhibit the LPS-induced tumor necrosis factor alpha (TNF-alpha) release by decreasing serum LPS in vivo. Our work suggests that this peptide is worthy of further investigation as a potential anti-LPS agent in the treatment of septic shock.

  9. The immune response during the luteal phase of the ovarian cycle : increasing sensitivity of human monocytes to endotoxin

    NARCIS (Netherlands)

    Bouman, Annechien; Moes, H; Heineman, MJ; de Leij, LFMH; Faas, MM

    Objective: To test the hypothesis that during the luteal phase of the human ovarian cycle, as compared with the follicular phase, the percentage of cytokines producing peripheral monocytes after in vitro stimulation with endotoxin is increased. Design: Prospective study. Setting: Academic research

  10. Respiratory symptoms, fractional exhaled nitric oxide & endotoxin exposure among female flower farm workers in Ethiopia.

    Science.gov (United States)

    Nigatu, Amare W; Bråtveit, Magne; Deressa, Wakgari; Moen, Bente E

    2015-01-01

    Greenhouse workers are exposed to organic dusts, and they are thereby at risk of developing airway disorders. This study aims to measure personal endotoxin exposure, assess respiratory symptoms and measure fractional exhaled nitric oxide (FeNO) among female flower farm workers in Ethiopia. A cross-sectional study involving female workers (n = 248) from four flower farms was conducted. The workers were interviewed for respiratory symptoms using a standard questionnaire. Workers from two of these farms also participated in personal endotoxin sampling (46 workers, 75 measurements) on glass fiber filters (0.2 μm pore size) inside conductive 25 mm Millipore cassettes for sampling of the "total dust" fraction. They also participated in FeNO (n = 114) measurements with a portable electrochemistry-based sensor. Chi-square and independent t-tests were used to compare categorical and continuous variables respectively. A mixed-effects model was used to analyze exposure determinants. Endotoxin exposure had a geometric mean (GM) of 22.8 endotoxin units (EU)/m(3) with a maximum of 180 EU/m(3). Greenhouse workers had significantly higher endotoxin exposure than workers outside the greenhouses (GM = 26.7 vs. 19.3 EU/m(3) respectively; p farm was 21 months. Greenhouse workers had higher prevalence of self-reported respiratory symptoms than those outside greenhouses. However, after adjusting for education only blocked nose remained significant. The FeNO concentration ranged 5-166 ppb (GM = 14 ppb). Two workers had FeNO concentration above 50 ppb. FeNO levels differs significantly between the farms but there was no difference between workers inside and outside greenhouses. Greenhouse workers at flower farms had higher prevalence of blocked nose than workers outside, which may indicate the presence of rhinitis. Endotoxin exposure was low. There were few workers with objective signs of airway inflammation; this might be because the mean working time in the

  11. Diagnostic Test Accuracy of a 2-Transcript Host RNA Signature for Discriminating Bacterial vs Viral Infection in Febrile Children.

    Science.gov (United States)

    Herberg, Jethro A; Kaforou, Myrsini; Wright, Victoria J; Shailes, Hannah; Eleftherohorinou, Hariklia; Hoggart, Clive J; Cebey-López, Miriam; Carter, Michael J; Janes, Victoria A; Gormley, Stuart; Shimizu, Chisato; Tremoulet, Adriana H; Barendregt, Anouk M; Salas, Antonio; Kanegaye, John; Pollard, Andrew J; Faust, Saul N; Patel, Sanjay; Kuijpers, Taco; Martinón-Torres, Federico; Burns, Jane C; Coin, Lachlan J M; Levin, Michael

    signature was implemented as a disease risk score in the validation group (130 children, with 23 definite bacterial, 28 definite viral, and 79 indeterminate infections; median age, 17 months; 57% male), all 23 patients with microbiologically confirmed definite bacterial infection were classified as bacterial (sensitivity, 100% [95% CI, 100%-100%]) and 27 of 28 patients with definite viral infection were classified as viral (specificity, 96.4% [95% CI, 89.3%-100%]). When applied to additional validation datasets from patients with meningococcal and inflammatory diseases, bacterial infection was identified with a sensitivity of 91.7% (95% CI, 79.2%-100%) and 90.0% (95% CI, 70.0%-100%), respectively, and with specificity of 96.0% (95% CI, 88.0%-100%) and 95.8% (95% CI, 89.6%-100%). Of the children in the indeterminate groups, 46.3% (63/136) were classified as having bacterial infection, although 94.9% (129/136) received antibiotic treatment. This study provides preliminary data regarding test accuracy of a 2-transcript host RNA signature discriminating bacterial from viral infection in febrile children. Further studies are needed in diverse groups of patients to assess accuracy and clinical utility of this test in different clinical settings.

  12. Bacterial Motility As a Biosignature: Tests at Icy Moon Analogue Sites

    Science.gov (United States)

    Nadeau, J. L.; Lindensmith, C.; Deming, J. W.; Stocker, R.; Graff, E.; Serabyn, E.; Wallace, J. K.; Liewer, K.; Kuhn, J.

    2014-12-01

    Extraterrestrial life in our Solar System, if present, is almost certain to be microbial. Methods and technologies for unambiguous detection of living or extinct microorganisms are needed for life-detection missions to the Jovian and Saturnian moons, where liquid water is known to exist. Our research focuses specifically on microbial meaningful motion as a biosignature—"waving crowds" at the micron scale. Digital Holographic Microscopy (DHM) is an excellent tool for unambiguous identification of bacterial and protozoal swimming, even in the presence of turbidity, drift, and currents. The design of a holographic instrument with bacteria scale resolution was described in the previous talk. In this presentation, we will illustrate the design challenges for construction of a field instrument for extreme environments and space, and present plans for scientific investigations at analogue sites for the coming season. The challenges of creating a field instrument involve performance trade-offs, the ability to operate at extreme temperatures, and handling large volumes of data. A fully autonomous instrument without external cables or power is also desirable, and this is something that previous holographic instruments have not achieved. The primary issues for space exploration are identification of a laser and drive electronics that are qualified for the expected radiation environments of the moons around gas giant planets. Tests in Earth analogue environments will establish performance parameters as well as answer scientific questions that traditional microscopic techniques cannot. Specifically, we will visit a Greenland field site to determine whether or not microorganisms are motile within the brine-filled interior network of sea ice, and if they can be autonomously tracked using the instrument. Motility within the liquid phase of a frozen matrix has been hypothesized to explain how bacteria contribute to the biogeochemical signatures detected in ice, but observational

  13. Increased intestinal permeability correlates with sigmoid mucosa alpha-synuclein staining and endotoxin exposure markers in early Parkinson's disease.

    Directory of Open Access Journals (Sweden)

    Christopher B Forsyth

    Full Text Available Parkinson's disease (PD is the second most common neurodegenerative disorder of aging. The pathological hallmark of PD is neuronal inclusions termed Lewy bodies whose main component is alpha-synuclein protein. The finding of these Lewy bodies in the intestinal enteric nerves led to the hypothesis that the intestine might be an early site of PD disease in response to an environmental toxin or pathogen. One potential mechanism for environmental toxin(s and proinflammatory luminal products to gain access to mucosal neuronal tissue and promote oxidative stress is compromised intestinal barrier integrity. However, the role of intestinal permeability in PD has never been tested. We hypothesized that PD subjects might exhibit increased intestinal permeability to proinflammatory bacterial products in the intestine. To test our hypothesis we evaluated intestinal permeability in subjects newly diagnosed with PD and compared their values to healthy subjects. In addition, we obtained intestinal biopsies from both groups and used immunohistochemistry to assess bacterial translocation, nitrotyrosine (oxidative stress, and alpha-synuclein. We also evaluated serum markers of endotoxin exposure including LPS binding protein (LBP. Our data show that our PD subjects exhibit significantly greater intestinal permeability (gut leakiness than controls. In addition, this intestinal hyperpermeability significantly correlated with increased intestinal mucosa staining for E. coli bacteria, nitrotyrosine, and alpha-synuclein as well as serum LBP levels in PD subjects. These data represent not only the first demonstration of abnormal intestinal permeability in PD subjects but also the first correlation of increased intestinal permeability in PD with intestinal alpha-synuclein (the hallmark of PD, as well as staining for gram negative bacteria and tissue oxidative stress. Our study may thus shed new light on PD pathogenesis as well as provide a new method for earlier

  14. Fucoidan Extracted from Fucus evanescens Prevents Endotoxin-Induced Damage in a Mouse Model of Endotoxemia

    Directory of Open Access Journals (Sweden)

    Tatyana A. Kuznetsova

    2014-01-01

    Full Text Available An important problem of treating patients with endotoxemia is to find drugs to reduce the negative effects of endotoxin on the organism. We tested fucoidan (sulfated polysaccharide from the brown alga Fucus evanescens as a potential drug in a mouse model of endotoxemia inducted by lipopolysaccharide (LPS. The survival time of mice injected with LPS increased under fucoidan treatment compared with the group of mice injected with LPS only. The preventive administration of fucoidan to mice with endotoxemia resulted in inhibition of increased levels of proinflammatory cytokines (TNFα and IL-6, as well as decreasing of the processes of hypercoagulability. The parenteral or per os administration of fucoidan resulted in decreasing the degree of microcirculatory disorders and secondary dystrophic-destructive changes in parenchymal organs of mice with endotoxemia. Taken together, these results demonstrate that fucoidan prevents endotoxin-induced damage in a mouse model of endotoxemia and increases the mice’s resistance to LPS.

  15. A quantitative test of population genetics using spatiogenetic patterns in bacterial colonies.

    Science.gov (United States)

    Korolev, Kirill S; Xavier, João B; Nelson, David R; Foster, Kevin R

    2011-10-01

    It is widely accepted that population-genetics theory is the cornerstone of evolutionary analyses. Empirical tests of the theory, however, are challenging because of the complex relationships between space, dispersal, and evolution. Critically, we lack quantitative validation of the spatial models of population genetics. Here we combine analytics, on- and off-lattice simulations, and experiments with bacteria to perform quantitative tests of the theory. We study two bacterial species, the gut microbe Escherichia coli and the opportunistic pathogen Pseudomonas aeruginosa, and show that spatiogenetic patterns in colony biofilms of both species are accurately described by an extension of the one-dimensional stepping-stone model. We use one empirical measure, genetic diversity at the colony periphery, to parameterize our models and show that we can then accurately predict another key variable: the degree of short-range cell migration along an edge. Moreover, the model allows us to estimate other key parameters, including effective population size (density) at the expansion frontier. While our experimental system is a simplification of natural microbial community, we argue that it constitutes proof of principle that the spatial models of population genetics can quantitatively capture organismal evolution.

  16. Test of endothelial monolayer integrity in the presence or absence of ...

    African Journals Online (AJOL)

    Monolayer cultures of human umbilical vein endothelial cells were established and tested for the effects of endotoxin treatment and anti-TNF-a monoclonal antibodies following endotoxin treatment on albumin permeability and electrical conductance. Application of 40 -g(ml)-1 of endotoxin on human umbilical cord ...

  17. Effect of hyperbaric air on endotoxin from Bacteroides fragilis strains

    Czech Academy of Sciences Publication Activity Database

    Chmelař, D.; Kašíková, A.; Martineková, P.; Hájek, M.; Rozložník, M.; Brabec, Marek; Janečková, J.; Vobejdová, J.; Čižnár, I.

    2018-01-01

    Roč. 63, č. 3 (2018), s. 283-290 ISSN 0015-5632 Institutional support: RVO:67985807 Keywords : endotoxin * hyperbaric condition Subject RIV: EE - Microbiology, Virology Impact factor: 1.521, year: 2016

  18. Evaluation of small intestine bacterial overgrowth in patients with functional dyspepsia through H2 breath test

    Directory of Open Access Journals (Sweden)

    Michelle Bafutto Gomes Costa

    2012-12-01

    Full Text Available CONTEXT: Functional dyspepsia is a condition in which symptoms are not related to organic underlying disease; its pathogenesis is not well known. The small intestinal bacterial overgrowth (SIBO is characterized by the increase in the number and/or type of colonic bacteria in the upper gastrointestinal tract. The hypothesis of SIBO being associated to functional dyspepsia must be considered, since the impaired motility of the gastrointestinal tract is one of the main etiologic factors involved on both pathologies. OBJECTIVE: To determine if there is SIBO in patients with functional dyspepsia. METHODS: Case-control study, evaluating 34 patients: 23 functional dyspeptic and 11 non-dyspeptic (control group. Questionnaire applied based on Rome III criteria. The patients underwent H2-lactulose breath test, considered positive when: H2 peak exceeding 20 ppm, in relation to fasting, or two peaks exceeding 10 ppm sustained until 60 minutes. RESULTS: Of the 23 dyspeptic patients, 13 (56.5% obtained positive results for SIBO trough the H2-lactulose breath test. On control group, SIBO was not observed. The association between the dyspeptic group and the control group regarding SIBO was statistically significant, with P = 0.0052. In the group of dyspeptic patients, 12 (52.2% were using proton pump inhibitor; of these 9 (75% were positive for SIBO. In the control group, none of the 11 patients used proton pump inhibitors and SIBO was not observed. The association of the dyspeptic group using proton pump inhibitor that were positive for SIBO and the control group was statistically significant, with P = 0.0011. CONCLUSION: It was found that, patients with functional dyspepsia presented SIBO, when they underwent to H2-lactulose breath test, compared to the non-dyspeptic. In addition, it was observed a higher prevalence of SIBO in dyspeptic patients that were using proton pump inhibitors, compared to control group.

  19. Possibilities of avoidance and control of bacterial plant diseases when using pathogen-tested (certified) or - treated planting material

    NARCIS (Netherlands)

    Janse, J.; Wenneker, M.

    2002-01-01

    Testing of planting material for freedom from phytopathogenic bacteria is an important, although not exclusive, method for control of bacterial diseases of plants. Ideally, pathogen-free or pathogen-/disease-resistant planting material is desirable, but this situation is not always possible on a

  20. Usefulness of clinical data and rapid diagnostic tests to identify bacterial etiology in adult respiratory infections

    Directory of Open Access Journals (Sweden)

    Pilar Toledano-Sierra

    2015-01-01

    Full Text Available Respiratory tract infections are a common complaint and most of them, such as common cold and laryngitis, are viral in origin, so antibiotic use should be exceptional. However, there are other respiratory tract infections (sinusitis, pharyngitis, lower respiratory tract infections, and exacerbations of chronic obstructive pulmonary disease where a bacterial etiology is responsible for a non-negligible percentage, and antibiotics are often empirically indicated. The aim of the study is to identify the strength of the data obtained from the symptoms, physical examination and rapid diagnostic methods in respiratory infections in which antibiotic use is frequently proposed in order to improve diagnosis and influence the decision to prescribe these drugs. The review concludes that history, physical examination and rapid tests are useful to guide the need for antibiotic treatment in diseases such as acute sinusitis, acute pharyngitis, exacerbation of lower respiratory tract infection and chronic obstructive pulmonary disease. However, no isolated data is accurate enough by itself to confirm or rule out the need for antibiotics. Therefore, clinical prediction rules bring together history and physical examination, thereby improving the accuracy of the decision to indicate or not antibiotics.

  1. Analysis of different coating thickness on new type of planar interdigital sensors for endotoxin detection

    KAUST Repository

    Syaifudin, A. R Mohd

    2013-05-01

    New types of planar interdigital sensors have been fabricated on Silicon/Silicon Dioxide (Si/SiO2) wafers. The sensors were coated with pre-cursor silica functionalized with APTES (3-aminopropyltrietoxysilane) at different thicknesses. All sensors were then immobilized with Polymyxin, B (PmB). PmB is an antimicrobial peptide produced by the Gram-positive bacterium-Bacillus, has been immobilized on the coated sensors because of its specific binding properties to endotoxin. Studies were conducted to analyze the effect of different thicknesses of coatings on the sensitivity and selectivity of the sensors. It was observed sensors coated with 3 layers of coating has better sensitivity and selectivity to the target molecules (endotoxin) compared to sensors with 5 layers of coating. The repeatability and stability of the coated sensors were tested by multiple standard endotoxin measurement and it was observed that the sensors give a good reproducibility and stability up to six continuous measurements before the coating degrades. © 2013 IEEE.

  2. Treatment guided by rapid diagnostic tests for malaria in Tanzanian children: safety and alternative bacterial diagnoses

    Directory of Open Access Journals (Sweden)

    Sykes Alma

    2011-10-01

    Full Text Available Abstract Background WHO guidelines for the treatment of young children with suspected malaria have recently changed from presumptive treatment to anti-malarial treatment guided by a blood slide or malaria rapid diagnostic test (RDT. However, there is limited evidence of the safety of this policy in routine outpatient settings in Africa. Methods Children 3-59 months of age with a non-severe febrile illness and no obvious cause were enrolled over a period of one year in a malaria endemic area of Tanzania. Treatment was determined by the results of a clinical examination and RDT result, and blood culture and serum lactate were also collected. RDT-negative children were followed up over 14 days. Results Over the course of one year, 965 children were enrolled; 158 (16.4% were RDT-positive and treated with artemether-lumefantrine and 807 (83.4% were RDT-negative and treated with non-anti-malarial medicines. Compared with RDT-positives, RDT-negative children were on average younger with a lower axillary temperature and more likely to have a history of cough or difficulty in breathing. Six (0.6% children became RDT-positive after enrolment, all of whom were PCR-negative for Plasmodium falciparum DNA at enrolment. In addition, 12 (1.2% children were admitted to hospital, one with possible malaria, none of whom died. A bacterial pathogen was identified in 9/965 (0.9% children, eight of whom were RDT-negative and one was RDT-positive, but slide-negative. Excluding three children with Salmonella typhi, all of the children with bacteraemia were ≤12 months of age. Compared to double-read research slide results RDTs had a sensitivity of 97.8% (95%CI 96.9-98.7 and specificity of 96.3% (95%CI 96.3-98.4. Conclusions Use of RDTs to direct the use of anti-malarial drugs in young children did not result in any missed diagnoses of malaria although new infections soon after a consultation with a negative RDT result may undermine confidence in results. Invasive

  3. Concentration of airborne Staphylococcus aureus (MRSA and MSSA), total bacteria, and endotoxins in pig farms.

    Science.gov (United States)

    Masclaux, Frederic G; Sakwinska, Olga; Charrière, Nicole; Semaani, Eulalia; Oppliger, Anne

    2013-06-01

    Pigs are very often colonized by Staphylococcus aureus and transmission of such pig-associated S. aureus to humans can cause serious medical, hygiene, and economic problems. The transmission route of zoonotic pathogens colonizing farm animals to humans is not well established and bioaerosols could play an important role. The aim of this study was to assess the potential occupational risk of working with S. aureus-colonized pigs in Switzerland. We estimated the airborne contamination by S. aureus in 37 pig farms (20 nursery and 17 fattening units; 25 in summer, 12 in winter). Quantification of total airborne bacterial DNA, airborne Staphylococcus sp. DNA, fungi, and airborne endotoxins was also performed. In this experiment, the presence of cultivable airborne methicillin-resistant S. aureus (MRSA) CC398 in a pig farm in Switzerland was reported for the first time. Airborne methicillin-sensitive S. aureus (MSSA) was found in ~30% of farms. The average airborne concentration of DNA copy number of total bacteria and Staphylococcus sp. measured by quantitative polymerase chain reaction was very high, respectively reaching values of 75 (± 28) × 10(7) and 35 (± 9.8) × 10(5) copy numbers m(-3) in summer and 96 (± 19) × 10(8) and 40 (± 12) × 10(6) copy numbers m(-3) in winter. Total mean airborne concentrations of endotoxins (1298 units of endotoxin m(-3)) and fungi (5707 colony-forming units m(-3)) exceeded the Swiss recommended values and were higher in winter than in summer. In conclusion, Swiss pig farmers will have to tackle a new emerging occupational risk, which could also have a strong impact on public health. The need to inform pig farmers about biological occupational risks is therefore crucial.

  4. Endotoxin-induced inflammation disturbs melatonin secretion in ewe

    Directory of Open Access Journals (Sweden)

    Andrzej Przemysław Herman

    2017-12-01

    Full Text Available Objective The study examined the effect of intravenous administration of bacterial endotoxin—lipopolysaccharide (LPS —on the nocturnal secretion of melatonin and on the expression of enzymes of the melatonin biosynthetic pathway in the pineal gland of ewes, taking into account two different photoperiodic conditions: short-night (SN; n = 12 and long-night (LN; n = 12. Methods In both experiments, animals (n = 12 were randomly divided into two groups: control (n = 6 and LPS-treated (n = 6 one. Two hours after sunset, animals received an injection of LPS or saline. Blood samples were collected starting one hour after sunset and continuing for 3 hours after the treatment. The ewes were euthanized 3 hours after LPS/saline treatment. The concentration of hormones in plasma was assayed by radioimmunoassay. In the pineal gland, the content of serotonin and its metabolite was determined by HPLC; whereas the expression of examined genes and protein was assayed using real-time polymerase chain reaction and Western Blot, respectively. Results Endotoxin administration lowered (p<0.05 levels of circulating melatonin in animals from LN photoperiod only during the first hour after treatment, while in ewes from SN photoperiod only in the third hour after the injection. Inflammation more substantially suppressed biosynthesis of melatonin in ewes from SN photoperiod, which were also characterised by lower (p<0.05 cortisol concentrations after LPS treatment compared with animals from LN photoperiod. In the pineal gland of ewes subjected to SN photoperiod, LPS reduced (p<0.05 serotonin content and the expression of melatonin biosynthetic pathway enzymes, such as tryptophan hydroxylase and arylalkylamine-N-acetyltransferase. Pineal activity may be disturbed by circulating LPS and proinflammatory cytokines because the expression of mRNAs encoding their corresponding receptors was determined in this gland. Conclusion The present study showed that peripheral

  5. The bacterial contamination rate of glucose meter test strips in the hospital setting

    Science.gov (United States)

    Al-Rubeaan, Khalid A.; Saeb, Amr T. M.; AlNaqeb, Dhekra M.; AlQumaidi, Hamed M.; AlMogbel, Turki A.

    2016-01-01

    Objectives: To assess the rate of bacterial contamination of the multi-use vial and single-use packed glucose meter strips, and to identify the type and frequency of various bacterial contamination in different hospital wards. Methods: This prospective observational study was conducted by a team from the Strategic Center for Diabetes Research in 7 general hospitals in the Central region of Saudi Arabia during the period from August to September 2014 to assess the bacterial contamination rate of the unused strips. A total of 10,447 strips were cultured using proper agar media and incubated both aerobically and anaerobically. Results: The total bacterial contamination rate for the multi-use vials glucose strips was 31.7%, while single-use packed strips were not contaminated at all. Ministry of Health hospitals had the highest contamination rates compared with other hospitals. Critical, obstetric, and surgical wards had the highest bacterial isolates number, where most were in the risk group 3 according to the National Institute of Health guidelines. Staphylococcus species were the most common bacteria found. Conclusion: Glucose meter strips should be recognized as a source of bacterial contamination that could be behind serious hospital acquired infections. The hospital infection control team should adopt proper measures to implement protocols for glucose meter cleaning and glucose strips handling. PMID:27570855

  6. Oil composition of high-fat diet affects metabolic inflammation differently in connection with endotoxin receptors in mice.

    Science.gov (United States)

    Laugerette, Fabienne; Furet, Jean-Pierre; Debard, Cyrille; Daira, Patricia; Loizon, Emmanuelle; Géloën, Alain; Soulage, Christophe O; Simonet, Claire; Lefils-Lacourtablaise, Jennifer; Bernoud-Hubac, Nathalie; Bodennec, Jacques; Peretti, Noël; Vidal, Hubert; Michalski, Marie-Caroline

    2012-02-01

    Low-grade inflammation observed in obesity is a risk factor for cardiovascular disease. Recent studies revealed that this would be linked to gut-derived endotoxemia during fat digestion in high-fat diets, but nothing is known about the effect of lipid composition. The study was designed to test the impact of oil composition of high-fat diets on endotoxin metabolism and inflammation in mice. C57/Bl6 mice were fed for 8 wk with chow or isocaloric isolipidic diets enriched with oils differing in fatty acid composition: milk fat, palm oil, rapeseed oil, or sunflower oil. In vitro, adipocytes (3T3-L1) were stimulated or not with lipopolysaccharide (LPS; endotoxin) and incubated with different fatty acids. In mice, the palm group presented the highest level of IL-6 in plasma (P palm group was correlated with a greater ratio of LPS-binding protein (LBP)/sCD14 in plasma (P palm group, which was associated with lower inflammation in both plasma and adipose tissue despite higher plasma endotoxemia. Taken together, our results reveal that the palm oil-based diet resulted in the most active transport of LPS toward tissues via high LBP and low sCD14 and the greatest inflammatory outcomes. In contrast, a rapeseed oil-based diet seemed to result in an endotoxin metabolism driven toward less inflammatory pathways. This shows that dietary fat composition can contribute to modulate the onset of low-grade inflammation through the quality of endotoxin receptors.

  7. Frequent major errors in antimicrobial susceptibility testing of bacterial strains distributed under the Deutsches Krebsforschungszentrum Quality Assurance Program.

    Science.gov (United States)

    Boot, R

    2012-07-01

    The Quality Assurance Program (QAP) of the Deutsches Krebsforschungszentrum (DKFZ) was a proficiency testing system developed to service the laboratory animal discipline. The QAP comprised the distribution of bacterial strains from various species of animals for identification to species level and antibiotic susceptibility testing (AST). Identification capabilities were below acceptable standards. This study evaluated AST results using the DKFZ compilations of test results for all bacterial strains showing the number of participants reporting the strain as resistant (R), sensitive (S) or intermediate susceptible (I) to each antibiotic substance used. Due to lack of information about methods used, it was assumed that what the majority of the participants reported (R or S) was the correct test result and that an opposite result was a major error (ME). MEs occurred in 1375 of 14,258 (9.7%) of test results and ME% ranged from 0% to 23.2% per bacterial group-agent group combination. Considerable variation in MEs was found within groups of bacteria and within groups of agents. In addition to poor performance in proper species classification, the quality of AST in laboratory animal diagnostic laboratories seems far below standards considered acceptable in human diagnostic microbiology.

  8. Microencapsulated Bifidobacterium longum subsp. infantis ATCC 15697 Favorably Modulates Gut Microbiota and Reduces Circulating Endotoxins in F344 Rats

    Directory of Open Access Journals (Sweden)

    Laetitia Rodes

    2014-01-01

    Full Text Available The gut microbiota is a bacterial bioreactor whose composition is an asset for human health. However, circulating gut microbiota derived endotoxins cause metabolic endotoxemia, promoting metabolic and liver diseases. This study investigates the potential of orally delivered microencapsulated Bifidobacterium infantis ATCC 15697 to modulate the gut microbiota and reduce endotoxemia in F344 rats. The rats were gavaged daily with saline or microencapsulated B. infantis ATCC 15697. Following 38 days of supplementation, the treated rats showed a significant (P < 0.05 increase in fecal Bifidobacteria (4.34 ± 0.46 versus 2.45 ± 0.25% of total and B. infantis (0.28 ± 0.21 versus 0.52 ± 0.12 % of total and a significant (P < 0.05 decrease in fecal Enterobacteriaceae (0.80 ± 0.45 versus 2.83 ± 0.63% of total compared to the saline control. In addition, supplementation with the probiotic formulation reduced fecal (10.52 ± 0.18 versus 11.29 ± 0.16 EU/mg; P = 0.01 and serum (0.33 ± 0.015 versus 0.30 ± 0.015 EU/mL; P = 0.25 endotoxins. Thus, microencapsulated B. infantis ATCC 15697 modulates the gut microbiota and reduces colonic and serum endotoxins. Future preclinical studies should investigate the potential of the novel probiotic formulation in metabolic and liver diseases.

  9. Host defense peptides of thrombin modulate inflammation and coagulation in endotoxin-mediated shock and Pseudomonas aeruginosa sepsis.

    Directory of Open Access Journals (Sweden)

    Martina Kalle

    Full Text Available Gram-negative sepsis is accompanied by a disproportionate innate immune response and excessive coagulation mainly induced by endotoxins released from bacteria. Due to rising antibiotic resistance and current lack of other effective treatments there is an urgent need for new therapies. We here present a new treatment concept for sepsis and endotoxin-mediated shock, based on host defense peptides from the C-terminal part of human thrombin, found to have a broad and inhibitory effect on multiple sepsis pathologies. Thus, the peptides abrogate pro-inflammatory cytokine responses to endotoxin in vitro and in vivo. Furthermore, they interfere with coagulation by modulating contact activation and tissue factor-mediated clotting in vitro, leading to normalization of coagulation responses in vivo, a previously unknown function of host defense peptides. In a mouse model of Pseudomonas aeruginosa sepsis, the peptide GKY25, while mediating a modest antimicrobial effect, significantly inhibited the pro-inflammatory response, decreased fibrin deposition and leakage in the lungs, as well as reduced mortality. Taken together, the capacity of such thrombin-derived peptides to simultaneously modulate bacterial levels, pro-inflammatory responses, and coagulation, renders them attractive therapeutic candidates for the treatment of invasive infections and sepsis.

  10. Analusis by 252Cf plasma desorption mass spectrometry of Bordetella pertussis endotoxin after nitrous deamination

    Science.gov (United States)

    Deprun, C.; Karibian, D.; Caroff, M.

    1993-07-01

    Endotoxic lipopolysaccharides (LPSs) are the major components of Gram-negative bacterial outer membrane. Like many amphipathic molecules, they pose problems of heterogeneity, purity, solubility, and aggregation. Nevertheless, PDMS has recently have been applied to unmodified endotoxins composed of LPS having uip to five sugar units in their saccharide chain. The B. Pertussis LPSs, most of which have a dodecasaccharide domain, ahve been analysed by classical methods and the masses of the separate lipid and saccharide domains determined after rupture of the bond linking them. However, the acid treatment employed for these and most chemical analyses can also modify structures in the vicinity of the bond. In order to investigate this biologically-important region, the endotoxin was treated to nitrous deamination, which shortens the saccharide chain to five sugars, but preserves the acid-labile region of the LPS. The PDM spectrum of this derivative, which required new conditions for its desorption, confirmed the structure analysis and demonstrated the presence of at least four molecular species.

  11. Effects of aging on endotoxin tolerance induced by lipopolysaccharides derived from Porphyromonas gingivalis and Escherichia coli.

    Science.gov (United States)

    Sun, Ying; Li, Hui; Yang, Mi-Fang; Shu, Wei; Sun, Meng-Jun; Xu, Yan

    2012-01-01

    Periodontitis is a bacterially induced chronic inflammatory disease. Exposure of the host to periodontal pathogens and their virulence factors induces a state of hyporesponsiveness to subsequent stimulations, termed endotoxin tolerance. Aging has a profound effect on immune response to bacteria challenge. The aim of this study was to explore the effects of aging on endotoxin tolerance induced by Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide (LPS) and Escherichia coli (E. coli) LPS in murine peritoneal macrophages. We studied the cytokine production (TNF-α and IL-10) and Toll-like receptor 2, 4 (TLR2, 4) gene and protein expressions in peritoneal macrophages from young (2-month-old) and middle-aged (12-month-old) ICR mice following single or repeated P. gingivalis LPS or E. coli LPS stimulation. Pretreatment of peritoneal macrophages with P. gingivalis LPS or E. coli LPS resulted in a reduction in TNF-α production and an increase in IL-10 production upon secondary stimulation (plead to the incontrollable periodontal inflammation in older adults.

  12. Biophysical analysis of the interaction of granulysin-derived peptides with enterobacterial endotoxins.

    Science.gov (United States)

    Chen, Xi; Howe, Jörg; Andrä, Jörg; Rössle, Manfred; Richter, Walter; da Silva, Ana Paula Galvão; Krensky, Alan M; Clayberger, Carol; Brandenburg, Klaus

    2007-10-01

    To combat infections by Gram-negative bacteria, it is not only necessary to kill the bacteria but also to neutralize pathogenicity factors such as endotoxin (lipopolysaccharide, LPS). The development of antimicrobial peptides based on mammalian endotoxin-binding proteins is a promising tool in the fight against bacterial infections, and septic shock syndrome. Here, synthetic peptides derived from granulysin (Gra-pep) were investigated in microbiological and biophysical assays to understand their interaction with LPS. We analyzed the influence of the binding of Gra-pep on (1) the acyl chain melting of the hydrophobic moiety of LPS, lipid A, by Fourier-transform spectroscopy, (2) the aggregate structure of LPS by small-angle X-ray scattering and cryo-transmission electron microscopy, and 3) the enthalpy change by isothermal titration calorimetry. In addition, the influence of Gra-pep on the incorporation of LPS and LPS-LBP (lipopolysaccharide-binding protein) complexes into negatively charged liposomes was monitored. Our findings demonstrate a characteristic change in the aggregate structure of LPS into multilamellar stacks in the presence of Gra-pep, but little or no change of acyl chain fluidity. Neutralization of LPS by Gra-pep is not due to a scavenging effect in solution, but rather proceeds after incorporation into target membranes, suggesting a requisite membrane-bound step.

  13. Endotoxin increases pulmonary vascular protein permeability in the dog

    International Nuclear Information System (INIS)

    Welsh, C.H.; Dauber, I.M.; Weil, J.V.

    1986-01-01

    Endotoxin increases pulmonary vascular permeability consistently in some species but fails to reliably cause injury in the dog. We wondered whether this phenomenon depended on the method of injury assessment, as others have relied on edema measurement; we quantified injury by monitoring the rate of extravascular protein accumulation. /sup 113m/In-labeled protein and /sup 99m/Tc-labeled erythrocytes were injected into anesthetized dogs and monitored by an externally placed lung probe. A protein leak index, the rate of extravascular protein accumulation, was derived from the rate of increase in lung protein counts corrected for changes in intravascular protein activity. After administration of Salmonella enteriditis endotoxin (4 micrograms/kg), the protein leak index was elevated 2.5-fold (41.1 +/- 4.6 X 10(-4) min-1) compared with control (16.0 +/- 2.8 X 10(-4) min-1). In contrast, wet-to-dry weight ratios failed to increase after endotoxin (4.6 +/- 0.8 vs. control values of 4.2 +/- 0.5 g/g dry bloodless lung). However, we observed that endotoxin increased lung dry weight (per unit body weight), which may have attenuated the change in wet-to-dry weight ratios. To determine whether low microvascular pressures following endotoxin attenuated edema formation, we increased pulmonary arterial wedge pressures in five dogs by saline infusion, which caused an increase in wet-to-dry weight ratios following endotoxin but no change in the five controls. We conclude that low dose endotoxin causes pulmonary vascular protein leak in the dog while edema formation is minimal or absent

  14. Histological analysis of the association between formocresol and endotoxin in the subcutaneous tissue of mice.

    Science.gov (United States)

    Sant'anna, Ana Teresa; Spolidório, Luis Carlos; Ramalho, Lizeti Toledo Oliveira

    2008-01-01

    This study performed a histological analysis of the effect of formocresol associated to endotoxin (LPS) in the subcutaneous connective tissue of mice. Ninety mice were randomly assigned to 3 groups (n=30). Each animal received one plastic tube implant containing endotoxin solution (10 mg/mL), formocresol (original formula) or a mixture of endotoxin and formocresol. The endotoxin and formocresol groups served as controls. The periods of analysis were 7, 15 and 30 days. At each experimental period, tissue samples were collected and submitted to routine processing for histological analysis. Endotoxin and formocresol produced necrosis and chronic inflammation at 7 and 15 days. At 30 days, the endotoxin group showed no necrosis, while in the formocresol group necrosis persisted. The formocresol-endotoxin association produced necrosis and chronic inflammation in the same way as observed with formocresol at all experimental periods. In conclusion, formocresol seems not to be able to inactive the toxic effects of endotoxin in connective tissues.

  15. Histological analysis of the association between formocresol and endotoxin in the subcutaneous tissue of mice

    OpenAIRE

    Sant'anna, Ana Teresa; Spolidório, Luis Carlos; Ramalho, Lizeti Toledo Oliveira

    2008-01-01

    This study performed a histological analysis of the effect of formocresol associated to endotoxin (LPS) in the subcutaneous connective tissue of mice. Ninety mice were randomly assigned to 3 groups (n=30). Each animal received one plastic tube implant containing endotoxin solution (10 mg/mL), formocresol (original formula) or a mixture of endotoxin and formocresol. The endotoxin and formocresol groups served as controls. The periods of analysis were 7, 15 and 30 days. At each experimental per...

  16. Histopathological and ultrastructural effects of delta-endotoxins of Bacillus thuringiensis serovar israelensis in the midgut of Simulium pertinax larvae (Diptera, Simuliidae

    Directory of Open Access Journals (Sweden)

    CFG Cavados

    2004-08-01

    Full Text Available The bacterium Bacillus thuringiensis (Bt produces parasporal crystals containing delta-endotoxins responsible for selective insecticidal activity on larvae. Upon ingestion, these crystals are solubilized in the midgut lumen and converted into active toxins that bind to receptors present on the microvilli causing serious damage to the epithelial columnar cells. We investigated the effect of these endotoxins on larvae of the Simulium pertinax, a common black fly in Brazil, using several concentrations during 4 h of the serovar israelensis strain IPS-82 (LFB-FIOCRUZ 584, serotype H-14 type strain of the Institute Pasteur, Paris. Light and electron microscope observations revealed, by time and endotoxin concentration, increasing damages of the larvae midgut epithelium. The most characteristic effects were midgut columnar cell vacuolization, microvilli damages, epithelium cell contents passing into the midgut lumen and finally the cell death. This article is the first report of the histopathological effects of the Bti endotoxins in the midgut of S. pertinax larvae and the data obtained may contribute to a better understanding of the mode of action of this bacterial strain used as bioinsecticide against black fly larvae.

  17. Recombinant factor C (rFC) assay and gas chromatography/mass spectrometry (GC/MS) analysis of endotoxin variability in four agricultural dusts.

    Science.gov (United States)

    Saito, Rena; Cranmer, Brian K; Tessari, John D; Larsson, Lennart; Mehaffy, John M; Keefe, Thomas J; Reynolds, Stephen J

    2009-10-01

    Endotoxin exposure is a significant concern in agricultural environments due to relatively high exposure levels. The goals of this study were to determine patterns of 3-hydroxy fatty acid (3-OHFA) distribution in dusts from four types of agricultural environments (dairy, cattle feedlot, grain elevator, and corn farm) and to evaluate correlations between the results of gas chromatography/mass spectrometry (GC/MS) analysis (total endotoxin) and biological recombinant factor C (rFC) assay (free bioactive endotoxin). An existing GC/MS-MS method (for house dust) was modified to reduce sample handling and optimized for small amount (rFC assay and the modified GC/EI-MS results was feedlot (0.72) > dairy (0.53) > corn farm (0.33) > grain elevator (0.11). In livestock environments, both odd- and even-numbered carbon chain length 3-OHFAs correlated with rFC assay response. The GC/EI-MS method should be especially useful for identification of specific 3-OHFAs for endotoxins from various agricultural environments and may provide useful information for evaluating the relationship between bacterial exposure and respiratory disease among agricultural workers.

  18. Effect of using ultrapure dialysate for hemodialysis on the level of circulating bacterial fragment in renal failure patients.

    Science.gov (United States)

    Kwan, Bonnie Ching-Ha; Chow, Kai-Ming; Ma, Terry King-Wing; Cheng, Phyllis Mei-Shan; Leung, Chi-Bon; Li, Philip Kam-Tao; Szeto, Cheuk-Chun

    2013-01-01

    Cardiovascular disease is the major cause of mortality and morbidity in dialysis patients. Recently, circulating endotoxin is found to associate with the systemic inflammatory state and cardiovascular disease of dialysis patients. Previous studies showed that the use of ultrapure dialysate for hemodialysis could reduce the exposure to exogenous endotoxin. We studied the effect of using ultrapure dialysate for hemodialysis on circulating endotoxin and bacterial DNA fragment levels and vascular stiffness. This is an open-labeled prospective study of 25 patients (14 male). Circulating endotoxin and bacterial DNA level, vascular stiffness as represented by arterial pulse wave velocity (PWV), nutrition and hydration status were monitored before and repeatedly throughout 12 months after the use of ultrapure dialysate for hemodialysis. The average age was 58.9 ± 10.2 years; 21 patients completed the study. Within 4 weeks of conversion to ultrapure dialysate for hemodialysis, the plasma endotoxin level fell from 0.302 ± 0.083 to 0.209 ± 0.044 EU/ml (p hemodialysis patients, circulating endotoxin level is associated with vascular stiffness and systemic inflammation. Using ultrapure dialysate for hemodialysis effectively reduces circulating endotoxin level in hemodialysis patients. The long-term benefit of using ultrapure dialysate for hemodialysis requires further study. © 2013 S. Karger AG, Basel.

  19. Endotoxin-induced antitumor activity in the mouse is highly potentiated by muramyl dipeptide

    NARCIS (Netherlands)

    Hofhuis, F.M.A.; Bloksma, N.; Willers, J.M.N.

    1984-01-01

    The ability of aqueous solutions of various endotoxin preparations, muramyl dipeptide (MDP) and combinations of endotoxin and MDP, to induce necrosis and regression of subcutaneous Meth A transplants in mice and their toxicity were studied. While intravenously injected toxic endotoxins, in contrast

  20. Influence of different cleaning practices on endotoxin exposure at sewage treatment plants

    NARCIS (Netherlands)

    Visser, M. J. [=Maaike J.; Spaan, S.; Arts, H. J. J. M.; Smit, L. A. M.; Heederik, D. J. J.

    2006-01-01

    Exposure to endotoxin at sewage treatment plants is associated with an increased prevalence of work-related symptoms in sewage workers. Since cleaning activities are regarded as an important determinant of endotoxin exposure, workers' endotoxin exposure levels during different cleaning activities

  1. A matrix of cholesterol crystals, but not cholesterol alone, primes human monocytes/macrophages for excessive endotoxin-induced production of tumor necrosis factor-alpha. Role in atherosclerotic inflammation?

    DEFF Research Database (Denmark)

    Bendtzen, Klaus; Christensen, Ole; Nielsen, Claus Henrik

    2014-01-01

    When exposed to small amounts of bacterial endotoxin, matrices of cholesterol crystals, but not cholesterol itself, primed human monocytes/macrophages to a highly augmented (>10-fold) production of inflammatory tumor necrosis factor-α. Priming also sensitized the cells, as 10- to 100-fold lower...... suggest that cholesterol matrix formation may play a pathogenic role in atherosclerotic inflammation, and they indicate a mechanism by which bacteria and/or bacterial products may play a role in processes leading to arteriosclerosis....

  2. A matrix of cholesterol crystals, but not cholesterol alone, primes human monocytes/macrophages for excessive endotoxin-induced production of tumor necrosis factor-alpha. Role in atherosclerotic inflammation?

    DEFF Research Database (Denmark)

    Bendtzen, Klaus; Christensen, Ole; Nielsen, Claus Henrik

    2014-01-01

    When exposed to small amounts of bacterial endotoxin, matrices of cholesterol crystals, but not cholesterol itself, primed human monocytes/macrophages to a highly augmented (>10-fold) production of inflammatory tumor necrosis factor-α. Priming also sensitized the cells, as 10- to 100-fold lower l...... suggest that cholesterol matrix formation may play a pathogenic role in atherosclerotic inflammation, and they indicate a mechanism by which bacteria and/or bacterial products may play a role in processes leading to arteriosclerosis....

  3. The role and reliability of rapid bedside diagnostic test in early diagnosis and treatment of bacterial meningitis.

    Science.gov (United States)

    Kumar, Arun; Debata, Pradeep Kumar; Ranjan, Amitabh; Gaind, Rajani

    2015-04-01

    To evaluate the role and reliability of rapid bedside diagnostic test in early diagnosis and treatment of bacterial meningitis in children using reagent strips. This prospective, single blinded study was conducted in the Department of Pediatrics of VMMC & Safdarjung Hospital, New Delhi in collaboration with the Department of Microbiology of VMMC & Safdarjung Hospital, New Delhi, over a period of 15 mo (August 2009 to Nov 2010). Seventy-five children aged 3 mo to 12 y admitted in the pediatric ward with suspected diagnosis of acute meningitis were included. All enroled patients underwent lumbar puncture. CSF samples were taken and divided in 2 parts for laboratory evaluation and rapid strip analysis. The sensitivity, specificity, positive predictive value and the negative predictive values of the reagent strips for the diagnosis of bacterial meningitis were calculated. Accuracy of the reagent strips was established using kappa statistics. Latex agglutination for antigen detection and microbiological culture were also done. Highly significant association was observed between CSF examination in routine laboratory method and dipstick method. The number of laboratory values that correlated were- for cells 71(94.63%), for protein 68 (90.67%), for glucose 68(90.67%) out of total 75 cases. The sensitivity and specificity of reagent strip in diagnosing acute bacterial meningitis were 96.7% and 97.8% respectively. The positive predictive and negative predictive values of reagent strip in diagnosing acute bacterial meningitis were 96.7% and 97.8% respectively. Staphylococcus aureus was found to be the most common organism isolated (50%). Thus reagent strip analysis is a very rapid, reliable and effective method for diagnosis of acute bacterial meningitis in children. Staphylococcus aureus was the most common organism isolated.

  4. Transepithelial activation of human leukocytes by probiotics and commensal bacteria: Role of Enterobacteriaceae-type endotoxin

    DEFF Research Database (Denmark)

    Baeuerlein, Annette; Ackermann, Stefanie; Parlesak, Alexandr

    2009-01-01

    The goal of the current study was to clarify whether commercially available probiotics induce greater trans-epithelial activation of human leukocytes than do commensal, food-derived and pathogenic bacteria and to identify the compounds responsible for this activation. Eleven different bacterial...... strains, and some of their pathogen-associated molecular patterns, were incubated apically on a confluent layer of intestinal epithelial cells (Caco-2), which were basolaterally co-cultured with human mononuclear leukocytes. Only Gram-negative bacteria having Enterobacteriaceae-type endotoxin (commensal...... Escherichia coli K12, probiotic E. coli Nissle, EPEC) induced basolateral production of TNF-alpha, IFN-gamma, IL 6, 8, and 10. Gram-positive probiotics (Lactobacillus spp. and Bifidobacterium spp.) had virtually no effect. In addition, commensals (Enterococcus faecalis, Bacteroides vulgatus) and food...

  5. Transepithelial activation of human leukocytes by probiotics and commensal bacteria: role of Enterobacteriaceae-type endotoxin

    DEFF Research Database (Denmark)

    Bäuerlein, A.; Ackermann, S.; Parlesak, Alexandr

    2009-01-01

    The goal of the current study was to clarify whether commercially available probiotics induce greater trans-epithelial activation of human leukocytes than do commensal, food-derived and pathogenic bacteria and to identify the compounds responsible for this activation. Eleven different bacterial...... strains, and some of their pathogen-associated molecular patterns, were incubated apically on a confluent layer of intestinal epithelial cells (Caco-2), which were basolaterally co-cultured with human mononuclear leukocytes. Only Gram-negative bacteria having Enterobacteriaceae-type endotoxin (commensal...... Escherichia coli K12, probiotic E. coli Nissle, EPEC) induced basolateral production of TNF-alpha, IFN-gamma, IL 6, 8, and 10. Gram-positive probiotics (Lactobacillus spp. and Bifidobacterium spp.) had virtually no effect. In addition, commensals (Enterococcus faecalis, Bacteroides vulgatus) and food...

  6. Investigation of bacterial transport in the large-block test, a thermally perturbed block of Topopah Spring tuff

    International Nuclear Information System (INIS)

    Chen, C.I.; Meike, A.; Chuu, Y.J.; Sawvel, A.; Lin, W.

    1999-01-01

    Transport of bacteria is investigated as part of the Large-Block Test (LBT), a thermally perturbed block of Topopah Spring tuff. Two bacterial species, Bacillus subtilis and Arthrobacter oxydans, were isolated from the Yucca Mountain Tuff. Natural mutants that can grow under the simultaneous presence of the two antibiotics, streptomycin and rifampicin, were selected from these species by laboratory procedures, cultured, and injected into the five heater boreholes of the large block hours before heating was initiated. The temperature, as measured 5 cm above one of the heater boreholes, rose slowly over a matter of months to a maximum of 142 C and to 60 C at the top and bottom of the block. Samples were collected from boreholes located approximately 5 ft below the injection points. Double-drug-resistant microbes also appeared in the heater boreholes where the temperature had been sustainably high throughout the test. The number of double-drug-resistant bacteria that were identified in the collection boreholes increased with time until the heater was deactivated. Negative indications in the collection holes after the heater was deactivated support the supposition that these bacteria were the species that were injected. An apparent homogeneous distribution among the collection boreholes suggests no pattern to the migration of bacteria through the block. The relationship between bacterial migration and the movement of water is not yet understood. These observations indicate the possibility of rapid bacterial transport in a thermally perturbed geologic setting. The implications for colloid transport need to be reviewed

  7. Ozone killing action against bacterial and fungal species; microbiological testing of a domestic ozone generator.

    OpenAIRE

    Dyas, A; Boughton, B J; Das, B C

    1983-01-01

    The action of ozone generated from a small domestic device was examined with a view to using it in clinical isolation units accommodating immunosuppressed patients. Over a six-hour period in an average size room the device did not generate sufficient ozone to suppress bacterial and fungal growth. A useful bactericidal action, against a variety of human pathogens was achieved with ozone concentrations between 0.3 to 0.9 ppm. Bactericidal ozone concentrations are close to the limit permitted fo...

  8. Molecular viability testing of bacterial pathogens from a complex human sample matrix.

    Directory of Open Access Journals (Sweden)

    Kris M Weigel

    Full Text Available Assays for bacterial ribosomal RNA precursors (pre-rRNA have been shown to distinguish viable from inactivated bacterial cells in drinking water samples. Because the synthesis of pre-rRNA is rapidly induced by nutritional stimulation, viable bacteria can be distinguished from inactivated cells and free nucleic acids by measuring the production of species-specific pre-rRNA in samples that have been briefly stimulated with nutrients. Here, pre-rRNA analysis was applied to bacteria from serum, a human sample matrix. In contrast to drinking water, serum is rich in nutrients that might be expected to mask the effects of nutritional stimulation. Reverse transcriptase quantitative polymerase chain reaction (RT-qPCR assays were used to detect pre-rRNA of four bacterial species: Acinetobacter baumannii, Pseudomonas aeruginosa, Staphylococcus aureus, and the Mycobacterium tuberculosis complex. These species were chosen for their clinical significance and phylogenetic diversity (Proteobacteria, Firmicutes, and Actinobacteria. To maximize resolving power, pre-rRNA was normalized to genomic DNA of each pathogen. When viable cells were shifted from serum to bacteriological culture medium, rapid replenishment of pre-rRNA was always observed. Cells of P. aeruginosa that were inactivated in the presence of serum exhibited no pre-rRNA response to nutritional stimulation, despite strong genomic DNA signals in these samples. When semi-automated methods were used, pre-rRNA analysis detected viable A. baumannii cells in serum at densities of ≤100 CFU/mL in <5.5 hours. Originally developed for rapid microbiological analysis of drinking water, ratiometric pre-rRNA analysis can also assess the viability of bacterial cells derived from human specimens, without requiring bacteriological culture.

  9. Immunomodulatory effects of honey cannot be distinguished from endotoxin

    DEFF Research Database (Denmark)

    Timm, Michael; Bartelt, Stine; Hansen, Erik Wind

    2008-01-01

    observed in the cell based assays were similar to the responses induced by endotoxin alone. In addition, we determined that the immunomodulatory component present in the natural honeys was retained in the ultra filtrated fraction with a molecular weight greater than 20 kDa. The component was resistant...... to boiling and its immunomodulatory activity could be abrogated by the addition of polymyxin B. We speculate that the observed in vitro immunomodulatory effects of honey might solely be explained by the endotoxin content in the natural honeys....

  10. The strains recommended for use in the bacterial reverse mutation test (OECD guideline 471) can be certified as non-genetically modified organisms.

    Science.gov (United States)

    Sugiyama, Kei-Ichi; Yamada, Masami; Awogi, Takumi; Hakura, Atsushi

    2016-01-01

    The bacterial reverse mutation test, commonly called Ames test, is used worldwide. In Japan, the genetically modified organisms (GMOs) are regulated under the Cartagena Domestic Law, and organisms obtained by self-cloning and/or natural occurrence would be exempted from the law case by case. The strains of Salmonella typhimurium and Escherichia coli recommended for use in the bacterial reverse mutation test (OECD guideline 471), have been considered as non-GMOs because they can be constructed by self-cloning or naturally occurring bacterial strains, or do not disturb the biological diversity. The present article explains the reasons why these tester strains should be classified as non-GMOs.

  11. Exercise and IL-6 infusion inhibit endotoxin-induced TNF-alpha production in humans

    DEFF Research Database (Denmark)

    Starkie, Rebecca; Ostrowski, Sisse Rye; Jauffred, Sune

    2003-01-01

    and atherosclerosis. To test this hypothesis, we performed three experiments in which eight healthy males either rested (CON), rode a bicycle for 3 h (EX), or were infused with recombinant human IL-6 (rhIL-6) for 3 h while they rested. After 2.5 h, the volunteers received a bolus of Escherichia coli...... exercise and rhIL-6 infusion at physiological concentrations inhibit endotoxin-induced TNF-alpha production in humans. Hence, these data provide the first experimental evidence that physical activity mediates antiinflammatory activity and suggest that the mechanism include IL-6, which is produced...

  12. Size-fractionated PM10 monitoring in relation to the contribution of endotoxins in different polluted areas

    Science.gov (United States)

    Traversi, D.; Alessandria, L.; Schilirò, T.; Gilli, G.

    2011-07-01

    Particulate pollution is an environmental concern that is widespread and difficult to resolve. Recently various regulatory improvements around the world have been agreed upon to tackle this problem, especially as related to the fine fraction of particulates, which more closely correlates to human health effects than other fractions. The size-fractionation of inhalable particles and their organic composition represent a new area of research that has been poorly explored thus far. Endotoxins are a type of natural organic compound that can be found in particulate matter. They are correlated with Gram-negative bacterial contamination. Health outcomes associated with exposure to these toxins are not specific and often overlap with the health effects of PM (Particulate Matter) exposure, including asthma, bronchitis, acute respiratory distress syndrome and organic dust toxic syndrome. Very little information is available on the endotoxin distribution in different PM10 size fractions. This study examined PM10 size fractions and their endotoxin content. Sampling was conducted at five different locations: one urban, two rural and two rural sites that were highly influenced by large-scale farm animal production facilities. For each location, six different PM10 fractions were evaluated. PM10 sub-fractions were categorised as follows: PM 10-7.2 (1.15-31.30 μg m -3); PM 7.2-3.0 (1.86-30.73 μg m -3); PM 3.0-1.5 (1.74-13.90 μg m -3); PM 1.5-0.95 (0.24-10.57 μg m -3); PM 0.95-0.49 (1.22-14.33 μg m -3) and PM <0.49 (13.15-85.49 μg m -3). The ranges of endotoxin levels determined were: PM 10-7.2 (0.051-5.401 endotoxin units (EU) m -3); PM 7.2-3.0 (0.123-7.801 EU m -3); PM 3.0-1.5 (0.057-1.635 EU m -3); PM 1.5-0.95 (0.040-2.477 EU m -3); PM 0.95-0.49 (0.007-3.159 EU m -3) and PM <0.49 (0.039-3.975 EU m -3). Our results indicated consistency of the PM1 fraction at all of the sites and the predominant presence of endotoxins in the coarse fraction. The observed abatement of the PM

  13. The effect of endotoxin and anti-endotoxin serum on synovial fluid parameters in the horse

    Directory of Open Access Journals (Sweden)

    R.D. Gottschalk

    1998-07-01

    Full Text Available The effects of a commercially available equine hyperimmune anti-endotoxin serum on synovial fluid parameters were evaluated in an induced synovitis model in normal horses. Four groups of 3 horses each received lipopolysaccharide (LPS plus hyperimmune antiendotoxin (anti-LPS, LPS, anti-LPS, and Ringers lactate (control respectively injected into the left intercarpal joint. Synovial fluid parameters were measured at 4, 8, 24 and 72 h. It was found that anti-LPS had no attenuating effect on the LPS and that it induced a synovitis almost equivalent to that induced by LPS alone. The introduction of sterile Ringers lactate solution into the carpal joint together with repeated aseptic arthrocentesis induces a mild inflammatory response.

  14. Binding of /sup 125/I-labeled endotoxin to bovine, canine, and equine platelets and endotoxin-induced agglutination of canine platelets

    Energy Technology Data Exchange (ETDEWEB)

    Meyers, K.M.; Boehme, M.; Inbar, O.

    1982-10-01

    Endotoxin from Escherichia coli O127:B8, Salmonella abortus-equi and S minnesota induced clumping of some canine platelets (PLT) at a final endotoxin concentration of 1 microgram/ml. Endotoxin-induced clumping of canine PLT was independent of PLT energy-requiring processes, because clumping was observed with canine PLT incubated with 2-deoxy-D-glucose and antimycin A. The PLT responded to adenosine diphosphate before, but not after, incubation with the metabolic inhibitors. Endotoxin induced a slight and inconsistant clumping of bovine and equine PLT at high (mg/ml) endotoxin concentration. High-affinity binding sites could not be demonstrated on canine, bovine, and equine PLT, using /sup 125/I-labeled E coli O127:B8 endotoxin. Nonspecific binding was observed and appeared to be due primarily to an extraneous coat on the PLT surface that was removed by gel filtration. The endotoxin that was bound to PLT did not appear to modify PLT function. An attempt to identify plasma proteins that bound physiologically relevant amounts of endotoxin was not successful. The significance of the endotoxin-induced clumping or lack of it on the pathophysiology of endotoxemia is discussed.

  15. Role of sedimentary organic matter in bacterial sulfate reduction: the G model tested

    International Nuclear Information System (INIS)

    Westrich, J.T.; Berner, R.A.

    1984-01-01

    Laboratory study of the bacterial decomposition of Long Island Sound plankton in oxygenated seawater over a period of 2 years shows that the organic material undergoes decomposition via first-order kinetics and can be divided into two decomposable fractions, of considerably different reactivity, and a nonmetabolized fraction. This planktonic material, after undergoing varying degrees of oxic degradation, was added in the laboratory to anoxic sediment taken from a depth of 1 m at the NWC site of Long Island Sound and the rate of bacterial sulfate reduction in the sediment measured by the 35 S radiotracer technique. The stimulated rate of sulfate reduction was in direct proportion to the amount of planktonic carbon added. This provides direct confirmation of the first-order decomposition, or G model, for marine sediments and proves that the in situ rate of sulfate reduction is organic-matter limited. Slower sulfate reduction rates resulted when oxically degraded plankton rather than fresh plankton was added, and the results confirm the presence of the same two fractions of organic matter deduced from the oxic degradation studies. Near-surface Long Island Sound sediment, which already contains abundant readily decomposable organic matter, was also subjected to anoxic decomposition by bacterial sulfate reduction. The decrease in sulfate reduction rate with time parallels decreases in the amount of organic matter, and these results also indicate the presence of two fractions of organic carbon of distinctly different reactivity. From plots of the log of reduction rate vs. time two first-order rate constants were obtained that agree well with those derived from the plankton addition experiment. Together, the two experiments confirm the use of a simple multi-first-order rate law for organic matter decomposition in marine sediments

  16. Ozone killing action against bacterial and fungal species; microbiological testing of a domestic ozone generator.

    Science.gov (United States)

    Dyas, A; Boughton, B J; Das, B C

    1983-10-01

    The action of ozone generated from a small domestic device was examined with a view to using it in clinical isolation units accommodating immunosuppressed patients. Over a six-hour period in an average size room the device did not generate sufficient ozone to suppress bacterial and fungal growth. A useful bactericidal action, against a variety of human pathogens was achieved with ozone concentrations between 0.3 to 0.9 ppm. Bactericidal ozone concentrations are close to the limit permitted for human exposure however and further experiments are indicated.

  17. Leakage of Microbial Endotoxin through the Implant-Abutment Interface in Oral Implants: An In Vitro Study

    OpenAIRE

    Garrana, Rhoodie; Mohangi, Govindrau; Malo, Paulo; Nobre, Miguel

    2016-01-01

    Background. Endotoxin initiates osteoclastic activity resulting in bone loss. Endotoxin leakage through implant abutment connections negatively influences peri-implant bone levels. Objectives. (i) To determine if endotoxin can traverse different implant-abutment connection (IAC) designs; (ii) to quantify the amount of endotoxins traversing the IAC; (iii) to compare the in vitro comportments of different IACs. Materials and Methods. Twenty-seven IACs were inoculated with E. coli endotoxin. Six...

  18. Endotoxin exposure and atopic sensitization in adult pig farmers

    NARCIS (Netherlands)

    Portengen, L.; Preller, L.; Tielen, M.; Doekes, G.; Heederik, D.

    2005-01-01

    Background: Recent studies have reported a low prevalence of atopic sensitization and respiratory allergy in children growing up on farms. Objectives: We sought to evaluate the dose-response relationship between endotoxin and atopic sensitization in adult farmers and to assess the effect on

  19. Dephosphorylation of endotoxin by alkaline phosphatase in vivo

    NARCIS (Netherlands)

    Poelstra, Klaas; Bakker, W.W; Klok, P.A; Kamps, J.AAM; Hardonk, M.J; Meijer, D.K F

    1997-01-01

    Natural substrates for alkaline phosphatase (AP) are at present not identified despite extensive investigations. Difficulties in imagining a possible physiological function involve its extremely high pH optimum for the usual exogenous substrates and its localization as an ecto-enzyme. As endotoxin

  20. Immunological studies on albino rats against crude endotoxins of ...

    African Journals Online (AJOL)

    The genus Aeromonas comprises a group of organisms widely distributed in the environment, isolated from water, shallow tube wells, dug wells, piped water supply from sewage, children and adults with diarrhoea, and associated with disease in animals and man. The present work studied the effect of crude endotoxin ...

  1. Dust, endotoxin, fungi, and bacteria exposure as determined by work task, season, and type of plant in a flower greenhouse.

    Science.gov (United States)

    Thilsing, Trine; Madsen, Anne Mette; Basinas, Ioannis; Schlünssen, Vivi; Tendal, Kira; Bælum, Jesper

    2015-03-01

    Greenhouse workers are exposed to dust, endotoxin, fungi, and bacteria potentially causing airway inflammation as well as systemic symptoms. Knowledge about determinants of exposure is a prerequisite for efficient prevention through knowledge-based reduction in exposure. The objective of this study was to assess the occupational exposure in a flower greenhouse and to investigate the impact of work tasks on the intensity and variability in exposure. Seventy-six personal full-shift exposure measurements were performed on 38 employees in a Danish flower greenhouse producing Campanula, Lavandula, Rhipsalideae, and Helleborus. The samples were gravimetrically analysed for inhalable dust. Endotoxin was assessed by the Limulus Amoebocyte Lysate test and culture-based quantification of bacteria and fungi was performed. Information on the performed tasks during sampling was extracted from the greenhouse electronic task logging system. Associations between log-transformed exposure outcomes, season, and work tasks were examined in linear mixed-effects regression with worker identity as random effect. Measured concentrations ranged between 0.04 and 2.41mg m(-3) for inhalable dust and between 0.84 and 1097 EU m(-3) for endotoxin exposure, with the highest mean levels measured during Lavandula and Campanula handling, respectively. Personal exposure to fungi ranged between 1.8×10(2) and 3.4×10(6) colony-forming units (CFU) m(-3) and to bacteria between 1.6×10(1) and 4.2×10(5) CFU m(-3). Exposure to dust, endotoxin, fungi, and bacteria differed between seasons. Packing Lavandula, sticking, potting, and grading Rhipsalideae, and all examined tasks related to Campanula production except sticking increased dust exposure. Endotoxin exposure was increased during sticking Campanula and pinching or packing Rhipsalideae, and fungi exposure was elevated by subtasks performed in the research and development area for Campanula, and by potting, packing/dumping Campanula. Sticking and

  2. Molecular basis for endotoxin neutralization by amphipathic peptides derived from the alpha-helical cationic core-region of NK-lysin.

    Science.gov (United States)

    Brandenburg, Klaus; Garidel, Patrick; Fukuoka, Satoshi; Howe, Jörg; Koch, Michel H J; Gutsmann, Thomas; Andrä, Jörg

    2010-08-01

    An analysis of the interaction of the NK-lysin derived peptide NK-2 and of analogs thereof with bacterial lipopolysaccharide (LPS, endotoxin) was performed to determine the most important biophysical parameters for an effective LPS neutralization. We used microcalorimetry, FTIR spectroscopy, Zeta potential measurements, and small-angle X-ray scattering to analyze the peptide:LPS binding enthalpy, the accessible LPS surface charge, the fluidity of the LPS hydrocarbon chains, their phase transition enthalpy change, the aggregate structure of LPS, and how these parameters are modulated by the peptides. We conclude that (i) a high peptide:LPS binding affinity, which is facilitated by electrostatic and hydrophobic interactions and which leads to a positive Zeta potential, (ii) the formation of peptide-enriched domains, which destabilize the lipid packing, demonstrated by a drastic decrease of phase transition enthalpy change of LPS, and (iii) the multilamellarization of the LPS aggregate structure are crucial for an effective endotoxin neutralization by cationic peptides.

  3. Impact of certain household micropollutants on bacterial behavior. Toxicity tests/study of extracellular polymeric substances in sludge

    Energy Technology Data Exchange (ETDEWEB)

    Pasquini, Laure, E-mail: laure.pasquini@univ-lorraine.fr [Laboratoire Environnement et Minéralurgie-CNRS, Université de Lorraine, 15 Avenue du Charmois, 54501 Vandoeuvre-lès-Nancy Cedex (France); Merlin, Christophe [Laboratoire de Chimie, Physique et Microbiologie pour l' Environnement-CNRS, Université de Lorraine, 15 Avenue du Charmois, 54501 Vandoeuvre-lès-Nancy Cedex (France); Hassenboehler, Lucille [Laboratoire Environnement et Minéralurgie-CNRS, Université de Lorraine, 15 Avenue du Charmois, 54501 Vandoeuvre-lès-Nancy Cedex (France); Munoz, Jean-François [Laboratoire d' Hydrologie de Nancy, ANSES, 40 rue Lionnois, 54000 Nancy (France); Pons, Marie-Noëlle [Laboratoire Réactions et Génie des Procédés-CNRS, Université de Lorraine, 1 Rue Grandville, 54001 Nancy Cedex (France); Görner, Tatiana [Laboratoire Environnement et Minéralurgie-CNRS, Université de Lorraine, 15 Avenue du Charmois, 54501 Vandoeuvre-lès-Nancy Cedex (France)

    2013-10-01

    The impact of eight household micropollutants (erythromycin, ofloxacin, ibuprofen, 4-nonylphenol, triclosan, sucralose, PFOA and PFOS (PFAAs)) on the laboratory bacterial strain Escherichia coli MG1655 and on activated sludge from an urban wastewater treatment plant was studied. Growth-based toxicity tests on E. coli were performed for each micropollutants. The effect of micropollutants on activated sludge (at concentrations usually measured in wastewater up to concentrations disturbing the bacterial growth of E. coli) was examined in batch reactors and by comparison to a control reactor (without micropollutants). The bound extracellular polymeric substances (EPS) secreted by the sludge were measured by size exclusion chromatography and their overexpression was considered as an indicator of bacteria sensitivity to environmental changes. The chemical oxygen demand (COD) and the ammonium concentration were monitored to evaluate the biomass ability to remove the macropollution. Some micropollutants induced an increase of bound EPS in activated sludge flocs at concentrations depending on the micropollutant: erythromycin from 100 μg/L, ofloxacin from 10 μg/L, triclosan from 0.5 μg/L, 4-nonylphenol from 5000 μg/L and PFAAs from 0.1 μg/L. This suggests that the biomass had to cope with new conditions. Moreover, at high concentrations of erythromycin (10 mg/L) and ibuprofen (5 mg/L) bacterial populations were no longer able to carry out the removal of macropollution. Ibuprofen induced a decrease of bound EPS at all the studied concentrations, probably reflecting a decrease of general bacterial activity. The biomass was not sensitive to sucralose in terms of EPS production, however at very high concentration (1 g/L) it inhibited the COD decrease. Micropollution removal was also assessed. Ibuprofen, erythromycin, ofloxacin, 4-nonylphenol and triclosan were removed from wastewater, mainly by biodegradation. Sucralose and PFOA were not removed from wastewater at all, and

  4. Impact of certain household micropollutants on bacterial behavior. Toxicity tests/study of extracellular polymeric substances in sludge

    International Nuclear Information System (INIS)

    Pasquini, Laure; Merlin, Christophe; Hassenboehler, Lucille; Munoz, Jean-François; Pons, Marie-Noëlle; Görner, Tatiana

    2013-01-01

    The impact of eight household micropollutants (erythromycin, ofloxacin, ibuprofen, 4-nonylphenol, triclosan, sucralose, PFOA and PFOS (PFAAs)) on the laboratory bacterial strain Escherichia coli MG1655 and on activated sludge from an urban wastewater treatment plant was studied. Growth-based toxicity tests on E. coli were performed for each micropollutants. The effect of micropollutants on activated sludge (at concentrations usually measured in wastewater up to concentrations disturbing the bacterial growth of E. coli) was examined in batch reactors and by comparison to a control reactor (without micropollutants). The bound extracellular polymeric substances (EPS) secreted by the sludge were measured by size exclusion chromatography and their overexpression was considered as an indicator of bacteria sensitivity to environmental changes. The chemical oxygen demand (COD) and the ammonium concentration were monitored to evaluate the biomass ability to remove the macropollution. Some micropollutants induced an increase of bound EPS in activated sludge flocs at concentrations depending on the micropollutant: erythromycin from 100 μg/L, ofloxacin from 10 μg/L, triclosan from 0.5 μg/L, 4-nonylphenol from 5000 μg/L and PFAAs from 0.1 μg/L. This suggests that the biomass had to cope with new conditions. Moreover, at high concentrations of erythromycin (10 mg/L) and ibuprofen (5 mg/L) bacterial populations were no longer able to carry out the removal of macropollution. Ibuprofen induced a decrease of bound EPS at all the studied concentrations, probably reflecting a decrease of general bacterial activity. The biomass was not sensitive to sucralose in terms of EPS production, however at very high concentration (1 g/L) it inhibited the COD decrease. Micropollution removal was also assessed. Ibuprofen, erythromycin, ofloxacin, 4-nonylphenol and triclosan were removed from wastewater, mainly by biodegradation. Sucralose and PFOA were not removed from wastewater at all, and

  5. Preclinical testing of radiopharmaceuticals for novel applications in HIV, bacterial and fungal infectious diseases

    International Nuclear Information System (INIS)

    Shah, M.; Garg, G.; Dadachova, E.

    2015-01-01

    Antibiotics, antifungal and antiviral medications have traditionally been used in the management of infections. Due to widespread emergence of resistance to antimicrobial medications, and their side effects, there is a growing need for alternative approaches for management of such conditions. Antibiotic resistant bacterial pathogens are on the rise. A cure has not been achieved for viral infections like AIDS, while fungal and parasitic infections are constant threats to the health of general public. The incidence of opportunistic infections in immunocompromised individuals like HIV patients, patients receiving high dose steroids, chemotherapy patients, and organ transplant recipients is on the rise. Radioimmunotherapy (RIT) has the potential to be a suitable and viable therapeutic modality in the arena of infection management. Provided the target-associated antigen is expressed by the target cells and minimally or not expressed by other tissues, selective targeting of radiation to target sites can be theoretically accomplished with relative sparing normal tissues from radiation exposure. In our laboratory we successfully demonstrated the effectiveness of RIT for treating infectious diseases. We targeted murine cryptococcosis with a mAb to the Cryptococcus neoformans capsular glucuronoxylomannan labeled with Bismuth-213 (213Bi) or Rhenium-188 (188Re). We subsequently extended the applicability of RIT for treating bacterial and viral infections. One of the advantages of using RIT to treat infections as opposed to cancer is that, in contrast to tumor cells, cells expressing microbial antigens are antigenically very different from host tissues and thus provide the potential for exquisite specificity and low cross-reactivity. Ever increasing incidence of infectious pathologies, exhaustion of antimicrobial possibilities and rising drug resistance calls for use of alternative and novel therapeutic options and we believe RIT is the need of the hour to combat these

  6. Airborne endotoxin concentrations at a large open-lot dairy in southern idaho.

    Science.gov (United States)

    Dungan, Robert S; Leytem, April B

    2009-01-01

    Endotoxins are derived from gram-negative bacteria and are a potential respiratory health risk for animals and humans. To determine the potential for endotoxin transport from a large open-lot dairy, total airborne endotoxin concentrations were determined at an upwind location (background) and five downwind locations on three separate days. The downwind locations were situated at of the edge of the lot, 200 and 1390 m downwind from the lot, and downwind from a manure composting area and wastewater holding pond. When the wind was predominantly from the west, the average endotoxin concentration at the upwind location was 24 endotoxin units (EU) m(-3), whereas at the edge of the lot on the downwind side it was 259 EU m(-3). At 200 and 1390 m downwind from the edge of the lot, the average endotoxin concentrations were 168 and 49 EU m(-3), respectively. Average airborne endotoxin concentrations downwind from the composting site (36 EU m(-3)) and wastewater holding pond (89 EU m(-3)) and 1390 m from the edge of the lot were not significantly different from the upwind location. There were no significant correlations between ambient weather data collected and endotoxin concentrations over the experimental period. The downwind data show that the airborne endotoxin concentrations decreased exponentially with distance from the lot edge. Decreasing an individual's proximity to the dairy should lower their risk of airborne endotoxin exposure and associated health effects.

  7. Inhibiting TNF-α signaling does not attenuate induction of endotoxin tolerance

    Directory of Open Access Journals (Sweden)

    Loosbroock C

    2014-12-01

    Full Text Available Christopher Loosbroock, Kenneth W Hunter Department of Microbiology and Immunology, University of Nevada School of Medicine, Reno, NV, USA Abstract: Tumor necrosis factor-alpha (TNF-α is a central mediator of inflammatory responses elicited by Toll-like receptor agonists, such as the Gram-negative bacterial outer membrane antigen lipopolysaccharide (LPS. TNF-α is responsible for altering vascular permeability and activating infiltrating inflammatory cells, such as monocytes and neutrophils. Interestingly, TNF-α has also demonstrated the ability to induce tolerance to subsequent challenges with TNF-α or LPS in monocyte and macrophage cell populations. Tolerance is characterized by the inability to mount a typical inflammatory response during subsequent challenges following the initial exposure to an inflammatory mediator such as LPS. The ability of TNF-α to induce a tolerant-like state with regard to LPS is most likely a regulatory mechanism to prevent excessive inflammation. We hypothesized that the induction of tolerance or the degree of tolerance is dependent upon the production of TNF-α during the primary response to LPS. To investigate TNF-α-dependent tolerance, human monocytic THP-1 cells were treated with TNF-α-neutralizing antibodies or antagonistic TNF-α receptor antibodies before primary LPS stimulation and then monitored for the production of TNF-α during the primary and challenge stimulation. During the primary stimulation, anti-TNF-α treatment effectively attenuated the production of TNF-α and interleukin-1β; however, this reduced production did not impact the induction of endotoxin tolerance. These results demonstrate that interfering with TNF-α signaling attenuates production of inflammatory cytokines without affecting the induction of tolerance. Keywords: endotoxin tolerance, lipopolysaccharide, tumor necrosis factor-alpha, anti-tumor necrosis factor-alpha, THP-1 cells

  8. Synthetic anti-endotoxin peptides inhibit cytoplasmic LPS-mediated responses.

    Science.gov (United States)

    Pfalzgraff, Anja; Heinbockel, Lena; Su, Qi; Brandenburg, Klaus; Weindl, Günther

    2017-09-15

    Toll-like receptor (TLR) 4-independent recognition of lipopolysaccharide (LPS) in the cytosol by inflammatory caspases leads to non-canonical inflammasome activation and induction of IL-1 secretion and pyroptosis. The discovery of this novel mechanism has potential implications for the development of effective drugs to treat sepsis since LPS-mediated hyperactivation of caspases is critically involved in endotoxic shock. Previously, we demonstrated that Pep19-2.5, a synthetic anti-endotoxin peptide, efficiently neutralises pathogenicity factors of Gram-negative and Gram-positive bacteria and protects against sepsis in vivo. Here, we report that Pep19-2.5 inhibits the effects of cytoplasmic LPS in human myeloid cells and keratinocytes. In THP-1 monocytes and macrophages, the peptide strongly reduced secretion of IL-1β and LDH induced by intracellular LPS. In contrast, the TLR4 signaling inhibitor TAK-242 abrogates LPS-induced TNF and IL-1β secretion, but not pyroptotic cell death. Furthermore, Pep19-2.5 suppressed LPS-induced HMGB-1 production and caspase-1 activation in THP-1 monocytes. Consistent with this observation, we found impaired IL-1β and IL-1α release in LPS-stimulated primary monocytes in the presence of Pep19-2.5 and reduced LDH release and IL-1B and IL-1A expression in LPS-transfected HaCaT keratinocytes. Additionally, Pep19-2.5 completely abolished IL-1β release induced by LPS/ATP in macrophages via canonical inflammasome activation. In conclusion, we provide evidence that anti-endotoxin peptides inhibit the inflammasome/IL-1 axis induced by cytoplasmic LPS sensing in myeloid cells and keratinocytes and activation of the classical inflammasome by LPS/ATP which may contribute to the protection against bacterial sepsis and skin infections with intracellular Gram-negative bacteria. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Biophysical characterization of the interaction of Limulus polyphemus endotoxin neutralizing protein with lipopolysaccharide.

    Science.gov (United States)

    Andrä, Jörg; Garidel, Patrick; Majerle, Andreja; Jerala, Roman; Ridge, Richard; Paus, Erik; Novitsky, Tom; Koch, Michel H J; Brandenburg, Klaus

    2004-05-01

    Endotoxin-neutralizing protein (ENP) of the horseshoe crab is one of the most potent neutralizers of endotoxins [bacterial lipopolysaccharide (LPS)]. Here, we report on the interaction of LPS with recombinant ENP using a variety of physical and biological techniques. In biological assays (Limulus amebocyte lysate and tumour necrosis factor-alpha induction in human mononuclear cells), ENP causes a strong reduction of the immunostimulatory ability of LPS in a dose-dependent manner. Concomitantly, the accessible negative surface charges of LPS and lipid A (zeta potential) are neutralized and even converted into positive values. The gel to liquid crystalline phase transitions of LPS and lipid A shift to higher temperatures indicative of a rigidification of the acyl chains, however, the only slight enhancement of the transition enthalpy indicates that the hydrophobic moiety is not strongly disturbed. The aggregate structure of lipid A is converted from a cubic into a multilamellar phase upon ENP binding, whereas the secondary structure of ENP does not change due to the interaction with LPS. ENP contains a hydrophobic binding site to which the dye 1-anilino-8-sulfonic acid binds at a K(d) of 19 micro m, which is displaced by LPS. Because lipopolysaccharide-binding protein (LBP) is not able to bind to LPS when ENP and LPS are preincubated, tight binding of ENP to LPS can be deduced with a K(d) in the low nonomolar range. Importantly, ENP is able to incorporate by itself into target phospholipid liposomes, and is also able to mediate the intercalation of LPS into the liposomes thus acting as a transport protein in a manner similar to LBP. Thus, LPS-ENP complexes might enter target membranes of immunocompetent cells, but are not able to activate due to the ability of ENP to change LPS aggregates from an active into an inactive form.

  10. Dynamic and selective nucleosome repositioning during endotoxin tolerance.

    Science.gov (United States)

    El Gazzar, Mohamed; Liu, Tiefu; Yoza, Barbara K; McCall, Charles E

    2010-01-08

    Sepsis is encoded by a sequel of transcription activation and repression events that initiate, sustain, and resolve severe systemic inflammation. The repression/silencing phase occurs in blood leukocytes of animals and humans following the initiation of systemic inflammation due to developing endotoxin tolerance. We previously reported that NF-kappaB transcription factor RelB and histone H3 lysine methyltransferase G9a directly interact to induce facultative heterochromatin assembly and regulate epigenetic silencing during endotoxin tolerance, which is a major feature of sepsis. The general objective of this study was to assess whether dynamic temporal, structural, and positional changes of nucleosomes influence the sepsis phenotype. We used the THP-1 sepsis cell model to isolate mononucleosomes by rapid cell permeabilization and digestion of chromatin with micrococcal nuclease and then compared tumor necrosis factor alpha (TNFalpha) proximal promoter nucleosome alignment in endotoxin-responsive and -tolerant phenotypes. We found differential and dynamic repositioning of nucleosomes from permissive to repressive locations during the activation and silencing phases of transcription reprogramming and identified the following mechanisms that may participate in the process. 1) Two proximal nucleosomes repositioned to expose the primary NF-kappaB DNA binding site in endotoxin-responsive cells, and this "promoter opening" required the ATP-independent chaperone NAP1 to replace the core histone H2A with the H2A.Z variant. 2) During RelB-dependent endotoxin tolerance, the two nucleosomes repositioned and masked the primary NF-kappaB DNA binding site. 3) Small interfering RNA-mediated inhibition of RelB expression prevented repressive nucleosome repositioning and tolerance induction, but the "open" promoter required endotoxin-induced NF-kappaB p65 promoter binding to initiate transcription, supporting the known requirement of p65 posttranslational modifications for

  11. A study of the effect of Bacillus thuringiensis serotype H14 (subspecies israelensis) delta endotoxin on Musca larva.

    Science.gov (United States)

    Mehrabi, Mohammad Reza; Zoghimofrad, Laya; Mazinani, Mahboubeh; Akbarzadeh, Azim; Rahimi, Amirabbas

    2015-01-01

    House flies (Musca domestica) are of major public health concern in areas with poor sanitation and hygiene conditions. Biological control through the use of parasitoids and pathogens is one of the alternatives to the use of chemical pesticides for control of insects of public health importance. The effects of the delta endotoxin of Bacillus thuringiensis on house fly larval mortality were studied. Gel filtration and SDS-PAGE methods were used for separation and purification of proteins. Delta endotoxin was incubated with larvae in concentrations of 0.43 mg/mL and 0.27 mg/mL in bioassay tests. The results of this study indicated protein crystal toxicity against larvae of the house fly. A concentration of 0.43 mg/mL of this toxin caused 100% mortality in house fly larvae. The LD50 amount of these toxins was calculated as 125 µg/g. The results of this study suggest that the use of the protein crystal including delta endotoxin of Bacillus thuringiensis serotype H14 is an effective weapon in the biological fight against the house fly.

  12. A suite of recombinant luminescent bacterial strains for the quantification of bioavailable heavy metals and toxicity testing.

    Science.gov (United States)

    Ivask, Angela; Rõlova, Taisia; Kahru, Anne

    2009-05-08

    Recombinant whole-cell sensors have already proven useful in the assessment of the bioavailability of environmental pollutants like heavy metals and organic compounds. In this work 19 recombinant bacterial strains representing various Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Escherichia coli, Pseudomonas fluorescens) bacteria were constructed to express the luminescence encoding genes luxCDABE (from Photorhabdus luminescens) as a response to bioavailable heavy metals ("lights-on" metal sensors containing metal-response elements, 13 strains) or in a constitutive manner ("lights-off" constructs, 6 strains). The bioluminescence of all 13 "lights-on" metal sensor strains was expressed as a function of the sub-toxic metal concentrations enabling the quantitative determination of metals bioavailable for these strains. Five sensor strains, constructed for detecting copper and mercury, proved to be target metal specific, whereas eight other sensor strains were simultaneously induced by Cd2+, Hg2+, Zn2+and Pb2+. The lowest limits of determination of the "lights-on" sensor strains for the metals tested in this study were (microg l-1): 0.002 of CH3HgCl, 0.03 of HgCl2, 1.8 of CdCl2, 33 of Pb(NO3)2, 1626 of ZnSO4, 24 of CuSO4 and 340 of AgNO3. In general, the sensitivity of the "lights-on" sensor strains was mostly dependent on the metal-response element used while the selection of host bacterium played a relatively minor role. In contrast, toxicity of metals to the "lights-off" strains was only dependent on the bacterial host so that Gram-positive strains were remarkably more sensitive than Gram-negative ones. The constructed battery of 19 recombinant luminescent bacterial strains exhibits several novel aspects as it contains i) metal sensor strains with similar metal-response elements in different host bacteria; ii) metal sensor strains with metal-response elements in different copies and iii) a "lights-off" construct (control) for every

  13. A suite of recombinant luminescent bacterial strains for the quantification of bioavailable heavy metals and toxicity testing

    Directory of Open Access Journals (Sweden)

    Kahru Anne

    2009-05-01

    Full Text Available Abstract Background Recombinant whole-cell sensors have already proven useful in the assessment of the bioavailability of environmental pollutants like heavy metals and organic compounds. In this work 19 recombinant bacterial strains representing various Gram-positive (Staphylococcus aureus and Bacillus subtilis and Gram-negative (Escherichia coli, Pseudomonas fluorescens bacteria were constructed to express the luminescence encoding genes luxCDABE (from Photorhabdus luminescens as a response to bioavailable heavy metals ("lights-on" metal sensors containing metal-response elements, 13 strains or in a constitutive manner ("lights-off" constructs, 6 strains. Results The bioluminescence of all 13 "lights-on" metal sensor strains was expressed as a function of the sub-toxic metal concentrations enabling the quantitative determination of metals bioavailable for these strains. Five sensor strains, constructed for detecting copper and mercury, proved to be target metal specific, whereas eight other sensor strains were simultaneously induced by Cd2+, Hg2+, Zn2+and Pb2+. The lowest limits of determination of the "lights-on" sensor strains for the metals tested in this study were (μg l-1: 0.002 of CH3HgCl, 0.03 of HgCl2, 1.8 of CdCl2, 33 of Pb(NO32, 1626 of ZnSO4, 24 of CuSO4 and 340 of AgNO3. In general, the sensitivity of the "lights-on" sensor strains was mostly dependent on the metal-response element used while the selection of host bacterium played a relatively minor role. In contrast, toxicity of metals to the "lights-off" strains was only dependent on the bacterial host so that Gram-positive strains were remarkably more sensitive than Gram-negative ones. Conclusion The constructed battery of 19 recombinant luminescent bacterial strains exhibits several novel aspects as it contains i metal sensor strains with similar metal-response elements in different host bacteria; ii metal sensor strains with metal-response elements in different copies and iii

  14. Evaluation of a Fast Test to Identify the Presence of Proline Aminopeptidase in Women With Bacterial Vaginosis

    Science.gov (United States)

    Rivera, Roberto; Gordillo, Silvia; Conde-Glez, Carlos

    1997-01-01

    Objective: The purpose of this study was to evaluate the activity of proline aminopeptidase by a rapid paper strip test in women with bacterial vaginosis (BV). Methods: Vaginal secretions of 1,387 voluntary patients attending the Obstetrics and Gynecology Infectious Diseases Clinic at Juárez Hospital of Mexico City were collected and examined. Patients were assigned into 2 groups: 483 with BV according to clinical and laboratory criteria and 604 without BV as the control group. For the purposes of this study, 300 patients with trichomonas and/or yeast were excluded from the BV group. The strips were prepared by using L-proline β-naphthylamide and L-proline p-nitroanilide as the substrates to detect proline aminopeptidase activity in concentrated vaginal secretions. In parallel, all samples were also analyzed with the standard methods in microplates containing either sustrate as a control of the rapid strip test. The test was interpreted after 3–5 min of incubation. Results: The results in the strip and microplate assays were similar in 95% of the samples. Sensitivity was 91.7% and specificity was 94.2%; probability of BV if the test is positive was 92.6% and negative predictive value was 93.4%. Conclusions: These findings indicate that this aminopeptidase rapid strip assay provides a 3–5 min identification of activity of the enzyme in women with BV. The procedure is a rapid, non-expensive, sensitive, and useful test at the gynecologic clinic. PMID:18476142

  15. The application of loop-mediated isothermal amplification (LAMP) in food testing for bacterial pathogens and fungal contaminants.

    Science.gov (United States)

    Niessen, Ludwig; Luo, Jie; Denschlag, Carla; Vogel, Rudi F

    2013-12-01

    Bacterial pathogens and toxicants, parasites as well as mycotoxin producing fungi are the major biotic factors influencing the safety of food. Moreover, viral infections and prions may be present as quasi biotic challenging factors. A vast array of culture dependent analytical methods and protocols for food safety testing has been developed during the past decades. Presently, protocols involving molecular biological techniques such as PCR-based nucleic acid amplification and hybridization have become available for many of the known pathogens with their major advantages being rapidness, high sensitivity and specificity. However, this type of assays is still quite labor- and cost intensive and mostly cannot be operated directly in the field. Recently, loop-mediated isothermal amplification (LAMP) of DNA has emerged as an alternative to the use of PCR-based methods not only in food safety testing but also in a wide array of application. Its advantages over PCR-based techniques are even shorter reaction time, no need for specific equipment, high sensitivity and specificity as well as comparably low susceptibility to inhibitors present in sample materials which enables detection of the pathogens in sample materials even without time consuming sample preparation. The present article presents a critical review of the application of LAMP-based methods and their usefulness in detecting and identifying food borne bacterial pathogens and toxicants as well as mycotoxin producing food borne fungi as compared to other methods. Moreover does it elaborate on new developments in the design and automation of LAMP-based assays and their implications for the future developments of food testing. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Assessment of Bacterial Blight Tolerance of Persian Walnut Based on Immature Nut Test

    Directory of Open Access Journals (Sweden)

    Attila BANDI

    2015-06-01

    Full Text Available Bacterial blight is one of the most serious diseases affecting Persian walnut (Juglans regia L.. Susceptibility to this disease was evaluated by artificial inoculation in an in vitro experiment for cultivars developed in Hungary and for selections from Transylvania. Thirty pieces of immature fruit of 11 walnut cultivars and 10 selections were inoculated by punction using a suspension containing a mixture of Xaj-isolates of controlled virulence. As control, a moderate resistant (mR ‘Pedro’ and a highly susceptible (hS ‘Milotai intenzív’ cultivars were used. After ten days the diameter of the necrotic area around the inoculation points was measured and the disease rate (DR was noted. For the calculation of indexes it was taken the structure of the lesions (diffuse or defined margin into consideration. None of the 21 cultivars/selections analysed were found to be hardly resistant, although all of them showed a higher degree of resistance than the susceptible control (‘Milotai intenzív’. The majority of the analysed cultivars fit into the moderate susceptible (mS and moderate resistant (mR group. ‘Milotai kései’ and SZEN-10, had a notable reaction as considered to be moderate resistant (mR, showed a similar degree of resistance compared to the control cultivar ‘Pedro’. It was concluded that these cultivars, based on their resistance to Xanthomonas arboricola pv. juglandis, could be proposed as resistance gene sources, as well as for production purposes in the environmental conditions of the Carpathian Basin.

  17. Comparison of Endotoxin Exposure Assessment by Bioaerosol Impinger and Filter-Sampling Methods

    OpenAIRE

    Duchaine, Caroline; Thorne, Peter S.; Mériaux, Anne; Grimard, Yan; Whitten, Paul; Cormier, Yvon

    2001-01-01

    Environmental assessment data collected in two prior occupational hygiene studies of swine barns and sawmills allowed the comparison of concurrent, triplicate, side-by-side endotoxin measurements using air sampling filters and bioaerosol impingers. Endotoxin concentrations in impinger solutions and filter eluates were assayed using the Limulus amebocyte lysate assay. In sawmills, impinger sampling yielded significantly higher endotoxin concentration measurements and lower variances than filte...

  18. Endotoxins in indoor air and settled dust in primary schools in a subtropical climate.

    Science.gov (United States)

    Salonen, Heidi; Duchaine, Caroline; Létourneau, Valérie; Mazaheri, Mandana; Clifford, Sam; Morawska, Lidia

    2013-09-03

    Endotoxins can significantly affect the air quality in school environments. However, there is currently no reliable method for the measurement of endotoxins, and there is a lack of reference values for endotoxin concentrations to aid in the interpretation of measurement results in school settings. We benchmarked the "baseline" range of endotoxin concentration in indoor air, together with endotoxin load in floor dust, and evaluated the correlation between endotoxin levels in indoor air and settled dust, as well as the effects of temperature and humidity on these levels in subtropical school settings. Bayesian hierarchical modeling indicated that the concentration in indoor air and the load in floor dust were generally (school environment and the need for further investigation. Metaregression indicated no relationship between endotoxin concentration and load, which points to the necessity for measuring endotoxin levels in both the air and settled dust. Temperature increases were associated with lower concentrations in indoor air and higher loads in floor dust. Higher levels of humidity may be associated with lower airborne endotoxin concentrations.

  19. Respiratory health effects of exposure to low levels of airborne endotoxin - a systematic review.

    Science.gov (United States)

    Farokhi, Azadèh; Heederik, Dick; Smit, Lidwien A M

    2018-02-08

    Elevated endotoxin levels have been measured in ambient air around livestock farms, which is a cause of concern for neighbouring residents. There is clear evidence that occupational exposure to high concentrations of airborne endotoxin causes respiratory inflammation, respiratory symptoms and lung function decline. However, health effects of exposure to low levels of endotoxin are less well described. The aim of this systematic review is to summarize published associations between exposure to relatively low levels of airborne endotoxin and respiratory health endpoints. Studies investigating respiratory effects of measured or modelled exposure to low levels of airborne endotoxin (average respiratory symptoms and lung function. However, considerable heterogeneity existed in the outcomes of the included studies and no overall estimate could be provided by meta-analysis to quantify the possible relationship. Instead, a best evidence synthesis was performed among studies examining the exposure-response relationship between endotoxin and respiratory outcomes. Significant exposure-response relationships between endotoxin and symptoms and FEV 1 were shown in several studies, with no conflicting findings in the studies included in the best evidence synthesis. Significantly different effects of endotoxin exposure were also seen in vulnerable subgroups (atopics and patients with broncho-obstructive disease) and smokers. Respiratory health effects of exposure to low levels of airborne endotoxin (respiratory health effects, especially in vulnerable subgroups of the population.

  20. Endotoxin level measurement in hemodialysis biofilm using "the whole blood assay".

    Science.gov (United States)

    Marion-Ferey, Karine; Leid, Jeff G; Bouvier, Ghislaine; Pasmore, Mark; Husson, Gilles; Vilagines, Rolland

    2005-06-01

    Biofilms have been found on the inner surface of silicone tubing inside dialysis machines. Endotoxin releasing from those biofilms increases the bioincompatibility of dialysis liquids and leads to long-term inflammatory complications among dialysis patients. Endotoxin measurement is recommended for the control of dialysis liquids. This article describes the use of a new method, the Whole Blood Assay (WBA), for endotoxin quantification in dialysis biofilms. Biofilms were suspended in sterile water by scraping the tubing samples. Diluted blood samples from healthy donors were stimulated overnight with the contaminated suspension. Stimulated mononuclear cells released IL-1beta in response to endotoxins. IL-1beta level was then measured using an ultrasensitive ELISA method. We demonstrated a semilogarithmic model in which the optical densities measured after the ELISA assay increases linearly with the levels of endotoxin. This model allowed the determination of the amount of endotoxins in biofilm samples with a detection limit of 0.032 EU/mL. Most of the time, the amounts of endotoxin measured by the WBA were higher than those measured by the Limulus Amoebocyte Lysate (LAL) assay. This study suggested the presence of "endotoxin-like" compounds different from the lipopolysaccharides that are not detected by the LAL assay. We concluded that the LAL is necessary but insufficient to have a representative quantification of endotoxins that could be hazardous to patient health.

  1. Evaluation of effectiveness of bacterial product which can degrade pesticide-dimethoate on the scale of true practice test

    International Nuclear Information System (INIS)

    Pham Thi Le Ha; Tran Thi Thuy; Le Hai; Nguyen Duy Hang; Vo Thi Thu Ha; Nguyen Tuong Ly Lan; Le Tat Mua; Tran Kim Duyen; Mai Hoang Lam

    2004-01-01

    Dimethoate, an organophosphate pesticide has been widely used in Dalat, Lamdong. It is much toxic to birds, human being and other mammals. Its widespread use has caused environmental concern on the basic of frequent detection of dimethoate in soil and water. Microorganisms are key agents in the degradation of waste, oil and a vast array of organic pesticide in terrestrial and aquatic ecosystems. In previous study, bacteria products which can degrade. Dimethoate were produced. The present study was designed to evaluate the effectiveness of bacterial product which can degrade Pesticide-Dimethoate on the scale of true practice test. The results indicated that application bacteria product to soil grown with Cauliflower and Chinese Cabbage sprayed with organic phosphorus pesticides (Dimethoate and Chloropyrifos), the pesticide residues in soil, water and vegetables were as follow: The residues of Dimethoate and Chloropyrifos in soil grown with Cauliflower, Chinese cabbages are different. They concentrated mostly in the surface litter and top soil layers with the depth from 0 to 20 cm. From the depth of 20 cm to 100 cm, the pesticide residues were ignorable. Residue of Chloropyrifos in soil was small as well. Dimethoate residues in soil grown with Cauliflower were higher than that of Chinese cabbages. On the basis of the environmental criteria of Ministry for Science, Technology and Environment (6/95), Dimethoate residues in soil grown with cauliflowers were in excess of the maximum limit. In the case of using bacteria product to soil, pesticide residues in soil were decreased. The results also indicated that Chloropyrifos residues in water (water obtained at the depth of 75 cm and 100 cm by days) were small. Residue of Dimethoate in water small. Residue of Dimethoate in water obtained from the Cauliflower bed were higher than of Chinese cabbages one. Using bacteria product to soil, pesticide residues in water decreased. On the basis of the environmental criteria of

  2. Investigation of bacterial transport in the large-block test, a thermally perturbed block of Topopah Spring Tuff

    International Nuclear Information System (INIS)

    Chen, C. I.; Chuu, Y. J.; Lin, W.; Meike, A.; Sawvel, A.

    1998-01-01

    This study investigates the transport of bacteria in a large, thermally perturbed block of Topopah Spring tuff. The study was part of the Large-Block Test (LBT), thermochemical and physical studies conducted on a 10 ft x 10 ft x 14 ft block of volcanic tuff excavated on 5 of 6 sides out of Fran Ridge, Nevada. Two bacterial species, Bacillus subtilis and Arthrobacter oxydans, were isolated from the Yucca Mountain tuff. Natural mutants that can grow under the simultaneous presence of the two antibiotics, streptomycin and rifampicin, were selected from these species by laboratory procedures. The double-drug-resistant mutants, which could be thus distinguished from the indigenous species, were injected into the five heater boreholes of the large block hours before heating was initiated. The temperature, as measured 5 cm above one of the heater boreholes, rose slowly and steadily over a matter of months to a maximum of 142 C. Samples (cotton cloths inserted the length of the hole, glass fiber swabs, and filter papers) were collected from the boreholes that were approximately 5 ft below the injection points. Double-drug-resistant bacteria were found in the collection boreholes nine months after injection. Surprisingly, they also appeared in the heater boreholes where the temperature had been sustainably high throughout the test. These bacteria appear to be the species that were injected. The number of double-drug-resistant bacteria that were identified in the collection boreholes increased with time. An apparent homogeneous distribution among the observation boreholes and heater boreholes suggests that a random motion could be the pattern that the bacteria migrated in the block. These observations indicated the possibility of rapid bacterial transport in a thermally perturbed geologic setting

  3. Study on security of sterile and non-pyrogenic disposable wares for medical use. Inactivation of endotoxins by γ-ray radiation in the presence of various drugs

    International Nuclear Information System (INIS)

    Hosobuchi, Kazunari; Tanamoto, Kenichi; Haijima, Yuji

    1997-01-01

    To efficiently inactivate endotoxins, γ-ray radiation to disposable wares for medical use was conducted using 185TBq 60 Co-radiation system in a medium added with various drugs. Endotoxin derived from E. coli R3F653 was used as the subject. Hydrogen peroxide solution, ethyl alcohol, or sodium hydrochloride were added to the basal medium. The activity of endotoxin was determined by limulus test with toxicolor system. The activity was markedly decreased by standing in 0.03% sodium hydrochloride solution for several days, whereas it was little affected in solutions of other two drugs at any concentration. However, γ-ray radiation in the medium added with either of those drugs caused to reduce the endotoxin activity dose-dependently. Such reducing effects by γ-ray radiation were most marked in the medium containing Na-hydrochloride at 0.03 or 0.3%, suggesting that there might be interaction of γ-ray and Na-hydrochloride. (M.N.)

  4. Problem-Solving Test: Attenuation--A Mechanism to Regulate Bacterial Tryptophan Biosynthesis

    Science.gov (United States)

    Szeberenyi, Jozsef

    2010-01-01

    Terms to be familiar with before you start to solve the test: tryptophan, transcription unit, operon, "trp" repressor, corepressor, operator, promoter, palindrome, initiation, elongation, and termination of transcription, open reading frame, coupled transcription/translation, chromosome-polysome complex. (Contains 2 figures and 1 footnote.)

  5. The micro-Ames test: A direct comparison of the performance and sensitivities of the standard and 24-well plate versions of the bacterial mutation test.

    Science.gov (United States)

    Proudlock, Raymond; Evans, Kristie

    2016-12-01

    "Ames" bacterial mutation tests are widely performed for evaluation and registration of new materials including industrial chemicals, agrochemicals, medical devices, pharmaceuticals, pharmaceutical impurities and other materials. Tests are used to predict their potential long-term adverse health effects (including carcinogenicity). Given their importance, pre-screening 'miniaturized' versions have been developed which allow higher throughput and use less test material, including the widely-employed 24-well micro-Ames (µAmes) test which uses 20 times less material. However, little quantitative information has been published on the methodology or sensitivity of this system. We describe methods and results used in direct comparisons of the sensitivity of micro and standard systems using the same cultures, formulations, etc. Initial testing utilized the plate incorporation method and, later, the pre-incubation method. In a subsequent phase of testing, a four-way direct comparison was made between the pre-incubation and plate incorporation methods in both systems using some direct-acting mutagens. Tests used only those strain/S9/chemical combinations where a response was expected. Historical control results accumulated during testing are also presented. Spontaneous and induced revertant colony counts for the µAmes system were consistently proportionate and approximately 1/20th those for the standard Ames test. Sensitivities of the two systems were found to be nearly identical in almost all cases for a wide variety of weak and strong inorganic and organic mutagens. Standardized procedures and increased reliability of the estimate of the background revertant frequency in the µAmes system means that the two systems give equivalent results and are expected to be highly predictive of one another. Environ. Mol. Mutagen. 57:687-705, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  6. Cathelicidin peptide sheep myeloid antimicrobial peptide-29 prevents endotoxin-induced mortality in rat models of septic shock.

    Science.gov (United States)

    Giacometti, Andrea; Cirioni, Oscar; Ghiselli, Roberto; Mocchegiani, Federico; D'Amato, Giuseppina; Circo, Raffaella; Orlando, Fiorenza; Skerlavaj, Barbara; Silvestri, Carmela; Saba, Vittorio; Zanetti, Margherita; Scalise, Giorgio

    2004-01-15

    The present study was designed to investigate the antiendotoxin activity and therapeutic efficacy of sheep myeloid antimicrobial peptide (SMAP)-29, a cathelicidin-derived peptide. The in vitro ability of SMAP-29 to bind LPS from Escherichia coli 0111:B4 was determined using a sensitive limulus chromogenic assay. Two rat models of septic shock were performed: (1) rats were injected intraperitoneally with 1 mg E. coli 0111:B4 LPS and (2) intraabdominal sepsis was induced via cecal ligation and single puncture. All animals were randomized to receive parenterally isotonic sodium chloride solution, 1 mg/kg SMAP-29, 1 mg/kg polymyxin B or 20 mg/kg imipenem. The main outcome measures were: abdominal exudate and plasma bacterial growth, plasma endotoxin and tumor necrosis factor-alpha concentrations, and lethality. The in vitro study showed that SMAP-29 completely inhibited the LPS procoagulant activity at approximately 10 microM peptide concentration. The in vivo experiments showed that all compounds reduced the lethality when compared with control animals. SMAP-29 achieved a substantial decrease in endotoxin and tumor necrosis factor-alpha plasma concentrations when compared with imipenem and saline treatment and exhibited a slightly lower antimicrobial activity than imipenem. No statistically significant differences were noted between SMAP-29 and polymyxin B. SMAP-29, because of its double antiendotoxin and antimicrobial activities, could be an interesting compound for septic shock treatment.

  7. Analysis of endotoxin and endothelin-1 levels in patients with type 1 hepatorenal syndrome

    Directory of Open Access Journals (Sweden)

    GAO Baoxiu

    2014-01-01

    Full Text Available ObjectiveTo analyze the clinical data, laboratory parameters, infection rate, and serum procalcitonin (PCT and ET-1 levels of patients with cirrhotic ascites and type 1 hepatorenal syndrome (HRS and to investigate the roles of endotoxin and ET-1 in the development of HRS. MethodsBetween January 2009 and October 2012, 56 inpatients with cirrhotic ascites and type 1 HRS (HRS group and 60 inpatients with cirrhotic ascites who had normal renal function (non-HRS group were included in the study. Their general data, causes of liver cirrhosis, infection rates and types, Child-Pugh classification, systemic inflammatory response syndrome (SIRS score, and mean arterial pressure (MAP were recorded; blood samples were collected to evaluate liver and renal function and measure serum electrolyte, PCT, and ET-1 levels. The clinical data and laboratory parameters were compared between the two groups. Categorical data were analyzed by chi-square test; comparison of normally distributed continuous data between the two groups was made by independent-samples t test, and comparison of non-normally distributed continuous data between the two groups was made by Wilcoxon rank sum test. ResultsThe infection rate of HRS group (75.0% was significantly higher than that of non-HRS group (28.4% (χ2=11.91, P<0.05. The PCT and ET-1 levels and SIRS score of HRS group [8.72 (3.14, 31.68 ng/L, 13.04±2.82 pg/ml, and 2.1±1.1] were significantly higher than those of non-HRS group [0.11 (0.04, 0.45 ng/L, 5.76±1.68 pg/ml, and 0.6±0.6] (P<0.05. In addition, the HRS group had significantly higher serum urea, creatine, cystatin C, and K levels than the non-HRS group (P<0.05, while the HRS group had significantly lower Na and Cl levels than the non-HRS group (P<0.05. There were no significant differences in ALT and AST levels between the two groups (P>005. ConclusionEndotoxin causes elevated expression of ET-1, and ET-1 induces renal perfusion deficiency by

  8. Multicenter Testing of the Rapid Quantification of Radical Oxygen Species in Cerebrospinal Fluid to Diagnose Bacterial Meningitis

    Science.gov (United States)

    Lukaszewicz, Anne-Claire; Faivre, Valérie; Bout, Hélène; Gayat, Etienne; Lagergren, Tina; Damoisel, Charles; Bresson, Damien; Paugam, Catherine; Mantz, Jean; Payen, Didier

    2015-01-01

    Purpose Meningitis is a serious concern after traumatic brain injury (TBI) or neurosurgery. This study tested the level of reactive oxygen species (ROS) in cerebrospinal fluid (CSF) to diagnose meningitis in febrile patients several days after trauma or surgery. Methods Febrile patients (temperature > 38°C) after TBI or neurosurgery were included prospectively. ROS were measured in CSF within 4 hours after sampling using luminescence in the basal state and after cell stimulation with phorbol 12-myristate 13-acetate (PMA). The study was conducted in a single-center cohort 1 (n = 54, training cohort) and then in a multicenter cohort 2 (n = 136, testing cohort) in the Intensive Care and Neurosurgery departments of two teaching hospitals. The performance of the ROS test was compared with classical CSF criteria, and a diagnostic decision for meningitis was made by two blinded experts. Results The production of ROS was higher in the CSF of meningitis patients than in non-infected CSF, both in the basal state and after PMA stimulation. In cohort 1, ROS production was associated with a diagnosis of meningitis with an AUC of 0.814 (95% confidence interval (CI) [0.684–0.820]) for steady-state and 0.818 (95% CI [0.655–0.821]) for PMA-activated conditions. The best threshold value obtained in cohort 1 was tested in cohort 2 and showed high negative predictive values and low negative likelihood ratios of 0.94 and 0.36 in the basal state, respectively, and 0.96 and 0.24 after PMA stimulation, respectively. Conclusion The ROS test in CSF appeared suitable for eliminating a diagnosis of bacterial meningitis. PMID:26011286

  9. Endotoxin, Ergosterol, Fungal DNA and Allergens in Dust from Schools in Johor Bahru, Malaysia- Associations with Asthma and Respiratory Infections in Pupils

    Science.gov (United States)

    Norbäck, Dan; Markowicz, Pawel; Cai, Gui-Hong; Hashim, Zailina; Ali, Faridah; Zheng, Yi-Wu; Lai, Xu-Xin; Spangfort, Michael Dho; Larsson, Lennart; Hashim, Jamal Hisham

    2014-01-01

    There are few studies on associations between respiratory health and allergens, fungal and bacterial compounds in schools in tropical countries. The aim was to study associations between respiratory symptoms in pupils and ethnicity, chemical microbial markers, allergens and fungal DNA in settled dust in schools in Malaysia. Totally 462 pupils (96%) from 8 randomly selected secondary schools in Johor Bahru, Malaysia, participated. Dust was vacuumed from 32 classrooms and analysed for levels of different types of endotoxin as 3-hydroxy fatty acids (3-OH), muramic acid, ergosterol, allergens and five fungal DNA sequences. Multiple logistic regression was applied. Totally 13.1% pupils reported doctor’s diagnosed asthma, 10.3% wheeze and 21.1% pollen or pet allergy. Indian and Chinese children had less atopy and asthma than Malay. Carbon dioxide levels were low (380–690 ppm). No cat (Fel d1), dog (Can f 1) or horse allergens (Ecu cx) were detected. The levels of Bloomia tropicalis (Blo t), house dust mite allergens (Der p 1, Der f 1, Der m 1) and cockroach allergens (Per a 1 and Bla g 1) were low. There were positive associations between levels of Aspergillus versicolor DNA and daytime breathlessness, between C14 3-OH and respiratory infections and between ergosterol and doctors diagnosed asthma. There were negative (protective) associations between levels of C10 3-OH and wheeze, between C16 3-OH and day time and night time breathlessness, between cockroach allergens and doctors diagnosed asthma. Moreover there were negative associations between amount of fine dust, total endotoxin (LPS) and respiratory infections. In conclusion, endotoxin at school seems to be mainly protective for respiratory illness but different types of endotoxin could have different effects. Fungal contamination measured as ergosterol and Aspergillus versicolor DNA can be risk factors for respiratory illness. The ethnical differences for atopy and asthma deserve further attention. PMID

  10. Endotoxin, ergosterol, fungal DNA and allergens in dust from schools in Johor Bahru, Malaysia- associations with asthma and respiratory infections in pupils.

    Science.gov (United States)

    Norbäck, Dan; Markowicz, Pawel; Cai, Gui-Hong; Hashim, Zailina; Ali, Faridah; Zheng, Yi-Wu; Lai, Xu-Xin; Spangfort, Michael Dho; Larsson, Lennart; Hashim, Jamal Hisham

    2014-01-01

    There are few studies on associations between respiratory health and allergens, fungal and bacterial compounds in schools in tropical countries. The aim was to study associations between respiratory symptoms in pupils and ethnicity, chemical microbial markers, allergens and fungal DNA in settled dust in schools in Malaysia. Totally 462 pupils (96%) from 8 randomly selected secondary schools in Johor Bahru, Malaysia, participated. Dust was vacuumed from 32 classrooms and analysed for levels of different types of endotoxin as 3-hydroxy fatty acids (3-OH), muramic acid, ergosterol, allergens and five fungal DNA sequences. Multiple logistic regression was applied. Totally 13.1% pupils reported doctor's diagnosed asthma, 10.3% wheeze and 21.1% pollen or pet allergy. Indian and Chinese children had less atopy and asthma than Malay. Carbon dioxide levels were low (380-690 ppm). No cat (Fel d1), dog (Can f 1) or horse allergens (Ecu cx) were detected. The levels of Bloomia tropicalis (Blo t), house dust mite allergens (Der p 1, Der f 1, Der m 1) and cockroach allergens (Per a 1 and Bla g 1) were low. There were positive associations between levels of Aspergillus versicolor DNA and daytime breathlessness, between C14 3-OH and respiratory infections and between ergosterol and doctors diagnosed asthma. There were negative (protective) associations between levels of C10 3-OH and wheeze, between C16 3-OH and day time and night time breathlessness, between cockroach allergens and doctors diagnosed asthma. Moreover there were negative associations between amount of fine dust, total endotoxin (LPS) and respiratory infections. In conclusion, endotoxin at school seems to be mainly protective for respiratory illness but different types of endotoxin could have different effects. Fungal contamination measured as ergosterol and Aspergillus versicolor DNA can be risk factors for respiratory illness. The ethnical differences for atopy and asthma deserve further attention.

  11. Endotoxin, ergosterol, fungal DNA and allergens in dust from schools in Johor Bahru, Malaysia- associations with asthma and respiratory infections in pupils.

    Directory of Open Access Journals (Sweden)

    Dan Norbäck

    Full Text Available There are few studies on associations between respiratory health and allergens, fungal and bacterial compounds in schools in tropical countries. The aim was to study associations between respiratory symptoms in pupils and ethnicity, chemical microbial markers, allergens and fungal DNA in settled dust in schools in Malaysia. Totally 462 pupils (96% from 8 randomly selected secondary schools in Johor Bahru, Malaysia, participated. Dust was vacuumed from 32 classrooms and analysed for levels of different types of endotoxin as 3-hydroxy fatty acids (3-OH, muramic acid, ergosterol, allergens and five fungal DNA sequences. Multiple logistic regression was applied. Totally 13.1% pupils reported doctor's diagnosed asthma, 10.3% wheeze and 21.1% pollen or pet allergy. Indian and Chinese children had less atopy and asthma than Malay. Carbon dioxide levels were low (380-690 ppm. No cat (Fel d1, dog (Can f 1 or horse allergens (Ecu cx were detected. The levels of Bloomia tropicalis (Blo t, house dust mite allergens (Der p 1, Der f 1, Der m 1 and cockroach allergens (Per a 1 and Bla g 1 were low. There were positive associations between levels of Aspergillus versicolor DNA and daytime breathlessness, between C14 3-OH and respiratory infections and between ergosterol and doctors diagnosed asthma. There were negative (protective associations between levels of C10 3-OH and wheeze, between C16 3-OH and day time and night time breathlessness, between cockroach allergens and doctors diagnosed asthma. Moreover there were negative associations between amount of fine dust, total endotoxin (LPS and respiratory infections. In conclusion, endotoxin at school seems to be mainly protective for respiratory illness but different types of endotoxin could have different effects. Fungal contamination measured as ergosterol and Aspergillus versicolor DNA can be risk factors for respiratory illness. The ethnical differences for atopy and asthma deserve further attention.

  12. The value of acute phase reactants and LightCycler® SeptiFast test in the diagnosis of bacterial and viral infections in pediatric patients.

    Science.gov (United States)

    Bozlu, Gulcin; Tanriverdi, Huseyin; Aslan, Gonul; Kuyucu, Necdet

    2018-02-01

    This study was performed to investigate the value of acute phase reactants and LightCycler® SeptiFast test to differentiate bacterial and viral infections. Children with fever were enrolled to this prospective study. Peripheral white blood cell (WBC), C-reactive protein (CRP) and procalcitonin (PCT) were studied from all patients on day 1, 3 and 7. Blood culture and chest X-ray were also obtained on day 1. Blood samples for LightCycler® SeptiFast test were obtained in all patients to use them if there was uncertain diagnosis between bacterial or viral infection. The patients were divided into two groups as bacterial and viral infection. A total of 94 children with fever were enrolled. The mean value of fever was significantly higher in bacterial group than viral group (p acute phase reactants, especially PCT, and LightCycler® SeptiFast test may help to differentiate bacterial and viral infections. Sociedad Argentina de Pediatría

  13. The specificity of Sushi peptides for endotoxin and anionic phospholipids: potential application of POPG as an adjuvant for anti-LPS strategies.

    Science.gov (United States)

    Li, P; Sun, M; Ho, B; Ding, J L

    2006-04-01

    Sushi peptides [S1 (Sushi 1 peptide) and S3] are derived from the LPS (lipopolysaccharide; also known as endotoxin)-binding domains of an LPS-sensitive serine protease, Factor C, from the horseshoe crab (Carcinoscorpius rotundicauda). S1 and S3 interact at high affinity with LPS. The intermolecular disulphide bonding in the S3 dimer is indispensable for its LPS binding, disruption and consequent neutralization. Simultaneously, the specific interaction between the Sushi peptides and bacterial membrane phospholipids further explains the selective propensity of these peptides for the gram-negative bacteria. Our findings yield insights into a complex molecular paradigm in which the juxtaposition of LPS molecules and the anionic phospholipid POPG (1-palmitoyl-2-oleoyl phosphatidylglycerol) on the bacterial outer membrane confers such interfacial properties which create the optimal environment for the interaction between the peptides and bacterial membrane lipids.

  14. Comparative Study of Plasma Endotoxin with Procalcitonin Levels in Diagnosis of Bacteremia in Intensive Care Unit Patients

    Directory of Open Access Journals (Sweden)

    Tao Wang

    2016-01-01

    Conclusions: Plasma endotoxin was more related to GN than to Gram-positive bacteremia, and that endotoxin level was species dependent, but PCT level remained relatively more stable within the GN bacteria caused bacteremia. Both GN and positive bacteria caused bacteremia in the ICU patients in different regions of China. And PCT is a more valuable biomarker than endotoxin in the diagnosis of bacteremia.

  15. DMPD: Gram-negative endotoxin: an extraordinary lipid with profound effects oneukaryotic signal transduction. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 1916089 Gram-negative endotoxin: an extraordinary lipid with profound effects oneuk...ep;5(12):2652-60. (.png) (.svg) (.html) (.csml) Show Gram-negative endotoxin: an extraordinary lipid with pr...tive endotoxin: an extraordinary lipid with profound effects oneukaryotic signal transduction. Authors Raetz

  16. Origin of endotoxemia influences the metabolic response to endotoxin in dogs

    NARCIS (Netherlands)

    Moeniralam, H. S.; Bemelman, W. A.; Romijn, J. A.; Endert, E.; Ackermans, M. T.; van Lanschot, J. J.; Hermsen, R. C.; Sauerwein, H. P.

    1997-01-01

    Different routes of endotoxin administration have been used to mimic inflammatory and metabolic responses observed during sepsis. Because the origin of endotoxemia may affect the reactions to endotoxin, we compared the induction of tumor necrosis factor (TNF), interleukin-6 (IL-6), hormones, and

  17. A method for in Vivo radiolabeling Bacillus thuringiensis native δ-endotoxin crystals

    Science.gov (United States)

    C. Noah Koller; Leah S. Bauer; Robert M. Hollingworth

    1995-01-01

    The entomocidal CryIIIA δ-endotoxin protein of Bacillus thuringiensis var. tenebrionis is distinctive in chemistry and host range. In contrast to other δ-endotoxins, the CryIIIA parasporal crystals are toxic within the acidic midgut environment of several coleopteran species, particularly those in the family...

  18. Experimental design and Bayesian networks for enhancement of delta-endotoxin production by Bacillus thuringiensis.

    Science.gov (United States)

    Ennouri, Karim; Ayed, Rayda Ben; Hassen, Hanen Ben; Mazzarello, Maura; Ottaviani, Ennio

    2015-12-01

    Bacillus thuringiensis (Bt) is a Gram-positive bacterium. The entomopathogenic activity of Bt is related to the existence of the crystal consisting of protoxins, also called delta-endotoxins. In order to optimize and explain the production of delta-endotoxins of Bacillus thuringiensis kurstaki, we studied seven medium components: soybean meal, starch, KH₂PO₄, K₂HPO₄, FeSO₄, MnSO₄, and MgSO₄and their relationships with the concentration of delta-endotoxins using an experimental design (Plackett-Burman design) and Bayesian networks modelling. The effects of the ingredients of the culture medium on delta-endotoxins production were estimated. The developed model showed that different medium components are important for the Bacillus thuringiensis fermentation. The most important factors influenced the production of delta-endotoxins are FeSO₄, K2HPO₄, starch and soybean meal. Indeed, it was found that soybean meal, K₂HPO₄, KH₂PO₄and starch also showed positive effect on the delta-endotoxins production. However, FeSO4 and MnSO4 expressed opposite effect. The developed model, based on Bayesian techniques, can automatically learn emerging models in data to serve in the prediction of delta-endotoxins concentrations. The constructed model in the present study implies that experimental design (Plackett-Burman design) joined with Bayesian networks method could be used for identification of effect variables on delta-endotoxins variation.

  19. Growth inhibitory effects of endotoxins from Bacteroides gingivalis and intermedius on human gingival fibroblasts in vitro

    International Nuclear Information System (INIS)

    Layman, D.L.; Diedrich, D.L.

    1987-01-01

    Purified endotoxin or lipopolysaccharide from Bacteroides gingivalis and Bacteroides intermedius caused a similar dose-dependent inhibition of growth of cultured human gingival fibroblasts as determined by 3 H-thymidine incorporation and direct cell count. Approximately 200 micrograms/ml endotoxin caused a 50% reduction in 3 H-thymidine uptake of logarithmically growing cells. Inhibition of growth was similar in cultures of fibroblasts derived from either healthy or diseased human gingiva. When examining the change in cell number with time of exposure in culture, the rate of proliferation was significantly suppressed during the logarithmic phase of growth. However, the cells recovered so that the rate of proliferation, although reduced, was sufficient to produce a cell density similar to the control cells with prolonged culture. The endotoxins were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The profiles of the Bacteroides endotoxins were different. B. gingivalis endotoxin showed a wide range of distinct bands indicating a heterogeneous distribution of molecular species. Endotoxin from B. intermedius exhibited a few discrete low molecular weight bands, but the majority of the lipopolysaccharides electrophoresed as a diffuse band of high molecular weight material. The apparent heterogeneity of the two Bacteroides endotoxins and the similarity in growth inhibitory capacity suggest that growth inhibitory effects of these substances cannot be attributed to any polysaccharide species of endotoxin

  20. Personal exposure to dust and endotoxin in Robusta and Arabica coffee processing factories in Tanzania.

    Science.gov (United States)

    Sakwari, Gloria; Mamuya, Simon H D; Bråtveit, Magne; Larsson, Lennart; Pehrson, Christina; Moen, Bente E

    2013-03-01

    Endotoxin exposure associated with organic dust exposure has been studied in several industries. Coffee cherries that are dried directly after harvest may differ in dust and endotoxin emissions to those that are peeled and washed before drying. The aim of this study was to measure personal total dust and endotoxin levels and to evaluate their determinants of exposure in coffee processing factories. Using Sidekick Casella pumps at a flow rate of 2l/min, total dust levels were measured in the workers' breathing zone throughout the shift. Endotoxin was analyzed using the kinetic chromogenic Limulus amebocyte lysate assay. Separate linear mixed-effects models were used to evaluate exposure determinants for dust and endotoxin. Total dust and endotoxin exposure were significantly higher in Robusta than in Arabica coffee factories (geometric mean 3.41 mg/m(3) and 10 800 EU/m(3) versus 2.10 mg/m(3) and 1400 EU/m(3), respectively). Dry pre-processed coffee and differences in work tasks explained 30% of the total variance for total dust and 71% of the variance for endotoxin exposure. High exposure in Robusta processing is associated with the dry pre-processing method used after harvest. Dust and endotoxin exposure is high, in particular when processing dry pre-processed coffee. Minimization of dust emissions and use of efficient dust exhaust systems are important to prevent the development of respiratory system impairment in workers.

  1. Exhaled nitric oxide in endotoxin-exposed adults: effect modification by smoking and atopy.

    NARCIS (Netherlands)

    Smit, L.A.; Heederik, D.J.J.; Doekes, G.; Wouters, I.M.

    2009-01-01

    OBJECTIVES: Occupational exposure to endotoxin is associated with non-allergic asthma and other airway inflammatory reactions. Little is known about the role of mucosal nitric oxide (NO) production in endotoxin-induced airway inflammation. The objective was to explore exposure-response relationships

  2. Surperoxide-mediated glomerulopathy in the endotoxin-treated pregnant rat

    NARCIS (Netherlands)

    Faas, MM; Schuiling, GA; Valkhof, N; Baller, JWF; Bakker, WW

    1998-01-01

    In the present study the role of superoxide in the glomerular damage in the low-dose endotoxin-infused pregnant rats was investigated. On day 14 of pregnancy, 12 rats were infused for 1 h with 1.0 mu g/kg bw endotoxin via a permanent jugular vein cannula. Of these rats, 6 were treated with SOD both

  3. Bacterial Keratitis

    Science.gov (United States)

    ... Español Eye Health / Eye Health A-Z Bacterial Keratitis Sections What Is Bacterial Keratitis? Bacterial Keratitis Symptoms ... Lens Care Bacterial Keratitis Treatment What Is Bacterial Keratitis? Leer en Español: ¿Qué Es la Queratitis Bacteriana? ...

  4. Insoluble glycogen, a metabolizable internal adsorbent, decreases the lethality of endotoxin shock in rats

    Directory of Open Access Journals (Sweden)

    S. Sipka

    1997-01-01

    Full Text Available Insoluble glycogen is an enzymatically modified form of naturally occurring soluble glycogen with a great adsorbing capacity. It can be metabolized by phagocytes to glucose. In this study we used insoluble glycogen intravenously in the experimental endotoxin shock of rats. Wistar male rats were sensitized to endotoxin by Pb acetate. The survival of rats were compared in groups of animals endotoxin shock treated and non-treated with insoluble glycogen. Furthermore, we have determined in vitro the binding capacity of insoluble glycogen for endotoxin, tumour necrosis factor alpha, interleukin-1 and secretable phospholipase A2. Use of 10 mg/kg dose of insoluble glycogen could completely prevent the lethality of shock induced by LD50 quantity of endotoxin in rats. All animals treated survived. Insoluble glycogen is a form of ‘metabolizable internal adsorbents’. It can potentially be used for treatment of septic shock.

  5. [Experience of using endotoxin selective adsorption in patients with severe sepsis after open-heart surgery].

    Science.gov (United States)

    Iarustovskiĭ, M B; Abramian, M V; Krotenko, N P; Popov, D A; Pliushch, M G; Nazarova, E I; Gordeev, S L

    2014-01-01

    To evaluate the safety and effectiveness of selective lipopolysaccharide (LPS)-adsorption therapy using polymyxin B immobilised fibre cartridges in adult patients complicated with severe sepsis after cardiac surgery. 105 patients received extracorporeal LPS-adsorption procedures using Toraymyxin columns--PMX (Toray, Japan) in addition to the standard treatment according to the Surviving Sepsis Campaign guideline study group. For control group we selected 40 patients, comparable by PMX group in age, body weight, severity of illness, and the duration of cardiopulmonary bypass, received only standard therapy. All patients received significant doses of vasoactive drugs for hemodynamic support, mechanical ventilation and broad-spectrum antibiotics. Mean APACHE II and SOFA scores were comparable for both groups. Inclusion criteria were: clinical signs of severe sepsis, endotoxin activity assay (EAA) > or = 0.6, elevated blood plasma procalcitonin (PCT) > 2 ng ml(-1). The inclusion criteria were clinical signs of severe sepsis, endotoxin activity assay (EAA) > or = 0.6, and blood plasma procalcitonin (PCT) > 2 ng ml(-1). Extracorporeal treatment was administered within 24 h of a severe sepsis diagnosis. Each patient in PMX group received 2 LPS-adsorption procedures and each session of hemoperfusion lasted for 120 minutes. After the LPS-adsorption course, we noted any indices of haemodynamic improvements, including an increase in mean arterial pressure on 22% (p < 0.001), mean oxygenation index (on 24.5%, p < 0.001), normalisation of leukocytosis and a decrease in mean body temperature. After the procedures of LPS-adsorption we found the statistically significant decreasing of LPS concentrations according to LAL-test and EAA. In the control group, there were no significant changes in any of the studied parameters except body temperature. Moreover, the 28-day mortality was 42% in the study group and 65% in the control group (p = 0.032). The endotoxin adsorption procedures

  6. Changes in endotoxin levels in T2DM subjects on anti-diabetic therapies

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    Kumar Sudhesh

    2009-04-01

    Full Text Available Abstract 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 ± (SD5.6 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 2 = 0.10; p 2 = 0.076; p 2 = 0.032; p 2 = 0.055; p 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.

  7. Anthrapyrazolone analogues intercept inflammatory JNK signals to moderate endotoxin induced septic shock

    Science.gov (United States)

    Prasad, Karothu Durga; Trinath, Jamma; Biswas, Ansuman; Sekar, Kanagaraj; Balaji, Kithiganahalli N.; Guru Row, Tayur N.

    2014-11-01

    Severe sepsis or septic shock is one of the rising causes for mortality worldwide representing nearly 10% of intensive care unit admissions. Susceptibility to sepsis is identified to be mediated by innate pattern recognition receptors and responsive signaling pathways of the host. The c-Jun N-terminal Kinase (JNK)-mediated signaling events play critical role in bacterial infection triggered multi-organ failure, cardiac dysfunction and mortality. In the context of kinase specificities, an extensive library of anthrapyrazolone analogues has been investigated for the selective inhibition of c-JNK and thereby to gain control over the inflammation associated risks. In our comprehensive biochemical characterization, it is observed that alkyl and halogen substitution on the periphery of anthrapyrazolone increases the binding potency of the inhibitors specifically towards JNK. Further, it is demonstrated that hydrophobic and hydrophilic interactions generated by these small molecules effectively block endotoxin-induced inflammatory genes expression in in vitro and septic shock in vivo, in a mouse model, with remarkable efficacies. Altogether, the obtained results rationalize the significance of the diversity oriented synthesis of small molecules for selective inhibition of JNK and their potential in the treatment of severe sepsis.

  8. Does adaptive radiation of a host lineage promote ecological diversity of its bacterial communities? A test using gut microbiota of Anolis lizards.

    Science.gov (United States)

    Ren, Tiantian; Kahrl, Ariel F; Wu, Martin; Cox, Robert M

    2016-10-01

    Adaptive radiations provide unique opportunities to test whether and how recent ecological and evolutionary diversification of host species structures the composition of entire bacterial communities. We used 16S rRNA gene sequencing of faecal samples to test for differences in the gut microbiota of six species of Puerto Rican Anolis lizards characterized by the evolution of distinct 'ecomorphs' related to differences in habitat use. We found substantial variation in the composition of the microbiota within each species and ecomorph (trunk-crown, trunk-ground, grass-bush), but no differences in bacterial alpha diversity among species or ecomorphs. Beta diversity analyses revealed subtle but significant differences in bacterial composition related to host phylogeny and species, but these differences were not consistently associated with Anolis ecomorph. Comparison of a trunk-ground species from this clade (A. cristatellus) with a distantly related member of the same ecomorph class (A. sagrei) where the two species have been introduced and are now sympatric in Florida revealed pronounced differences in the alpha diversity and beta diversity of their microbiota despite their ecological similarity. Comparisons of these populations with allopatric conspecifics also revealed geographic differences in bacterial alpha diversity and beta diversity within each species. Finally, we observed high intraindividual variation over time and strong effects of a simplified laboratory diet on the microbiota of A. sagrei. Collectively, our results indicate that bacterial communities are only weakly shaped by the diversification of their lizard hosts due to the strikingly high levels of bacterial diversity and variation observed within Anolis species. © 2016 John Wiley & Sons Ltd.

  9. Oregon ESA 2010 BKD vertical transmission - Test of analyses for bacterial kidney disease as predictors of vertical transmission

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Although the pathogen causing bacterial kidney disease is known to be transmitted from broodstock female to offspring, there is large uncertainty around the...

  10. A Meningococcal Outer Membrane Vesicle Vaccine Incorporating Genetically Attenuated Endotoxin Dissociates Inflammation From Immunogenicity

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    David J. Dowling

    2016-12-01

    Full Text Available Background. Group B Neisseria meningitidis, an endotoxin-producing gram-negative bacterium, causes the highest incidence of group B meningococcus (MenB disease in the first year of life. The Bexsero vaccine is indicated in Europe from 8 weeks of age. Endotoxin components of outer membrane vesicles (OMVs or soluble lipopolysaccharide (LPS represent a potential source of inflammation and residual reactogenicity. The purpose of this study was to compare novel candidate MenB vaccine formulations with licensed vaccines, including Bexsero, using age-specific in vitro culture systems.Methods. OMVs from wild type and inactivated lpxL1 gene mutant N. meningitidis strains were characterized in human neonatal and adult in vitro whole blood assays and dendritic cell arrays. OMVs were benchmarked against licensed vaccines, including Bexsero and whole cell pertussis formulations, with respect to Th-polarizing cytokine and PGE2 production, as well as cell surface activation markers (HLA-DR, CD86, CCR7. OMV immunogenicity was assessed in mice.Results. ΔlpxLI native OMVs demonstrated significantly less cytokine induction in human blood and DCs than Bexsero and most of the other pediatric vaccines (e.g., PedvaxHib, EasyFive, Bacillus Calmette–Guérin (BCG tested. Despite a much lower inflammatory profile in vitro than Bexsero, ΔlpxLI native OMVs still had moderate DC maturing ability and induced robust anti-N. meningitidis antibody responses after murine immunization.Conclusions. A meningococcal vaccine comprised of attenuated LPS-based OMVs with a limited inflammatory profile in vitro induces robust antigen-specific immunogenicity in vivo.

  11. Peptide-assembled graphene oxide as fluorescent turn-on sensor for ultrasensitive Lipopolysaccharide (Endotoxin detection

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    Seng Koon Lim

    2014-06-01

    Full Text Available Introduction: Lipopolysaccharide (LPS, or endotoxin, a major component in the outer cell membrane of Gram-negative bacteria is a very powerful and toxic inflammatory stimulator, resulting in sepsis or septic shock, a significant medical problem affecting about 700 000 patients and causing 250 000 casualties annually in the United States itself. The detection of LPS is highly importance. However, the currently used enzymatic limulus amebocyte lysate assay is highly susceptible to changes in temperature and pH, interference factors, and requires cumbersome sample preparation. A more cost-effective, sensitive and robust detection method is needed. Objective: To design and develop biosensor for LPS detection by assembling a LPS-binding peptide (as LPS receptor with graphene oxide (GO, as fluorescence quencher. Methods: GO was synthesized using a modified Hummer’s method. A synthetic LPS-binding peptide was designed, fluorescent labelled, and assembled with GO in PBS buffer solution. The fluorescence recovery of the peptide-GO was measured upon addition of LPS from Gram negative bacteria: E. coli, K. pneumoniae, Samonella Thyphosa, P. aeruginosa, as well as living pathogenic bacteria. Specificity tests were conducted with various biological molecules to evaluate the sensing performance. Results & Discussion: Specific binding of LPS with peptide release the peptides from GO, resulting in fluorescence recovery, allowing ultrasensitive detection of LPS with the limit of detection of 130 pM, the most sensitive synthetic LPS sensors to-date. The LPS sensor is highly selective to LPS than other biological species. Conclusion: We developed a peptide-GO assembled fluorescence sensor for ultrasensitive and specific LPS/endotoxin detection. This is the most sensitive synthetic LPS sensor reported in the world.

  12. Nutritional Supplement of Hatchery Eggshell Membrane Improves Poultry Performance and Provides Resistance against Endotoxin Stress.

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    S K Makkar

    Full Text Available Eggshells are significant part of hatchery waste which consist of calcium carbonate crust, membranes, and proteins and peptides of embryonic origins along with other entrapped contaminants including microbes. We hypothesized that using this product as a nutritional additive in poultry diet may confer better immunity to the chickens in the paradigm of mammalian milk that enhances immunity. Therefore, we investigated the effect of hatchery eggshell membranes (HESM as a short term feed supplement on growth performance and immunity of chickens under bacterial lipopolysaccharide (LPS challenged condition. Three studies were conducted to find the effect of HESM supplement on post hatch chickens. In the first study, the chickens were fed either a control diet or diets containing 0.5% whey protein or HESM as supplement and evaluated at 5 weeks of age using growth, hematology, clinical chemistry, plasma immunoglobulins, and corticosterone as variables. The second and third studies were done to compare the effects of LPS on control and HESM fed birds at 5 weeks of age following at 4 and 24 h of treatment where the HESM was also sterilized with ethanol to deplete bacterial factors. HESM supplement caused weight gain in 2 experiments and decreased blood corticosterone concentrations. While LPS caused a significant loss in body weight at 24 h following its administration, the HESM supplemented birds showed significantly less body weight loss compared with the control fed birds. The WBC, heterophil/lymphocyte ratio, and the levels of IgG were low in chickens fed diets with HESM supplement compared with control diet group. LPS challenge increased the expression of pro-inflammatory cytokine gene IL-6 but the HESM fed birds showed its effect curtailed, also, which also, favored the up-regulation of anti-inflammatory genes compared with control diet fed chickens. Post hatch supplementation of HESM appears to improve performance, modulate immunity, and increase

  13. Bactericidal and endotoxin neutralizing activity of a peptide derived from Limulus antilipopolysaccharide factor.

    Science.gov (United States)

    Weiss, C A; Wasiluk, K R; Kellogg, T A; Dunn, D L

    2000-08-01

    Release of lipopolysaccharide (endotoxin, LPS) is a critical inciting event in the development of sepsis syndrome due to gram-negative bacteria, and mortality associated with this entity remains approximately 40%. Limulus anti-LPS factor (LALF) is a naturally occurring horseshoe crab derived protein that, unlike antibiotics, is both bactericidal for gram-negative bacteria and capable of neutralizing LPS. We hypothesized that a peptide derived from the active domain of LALF (LALF #28-54) would exhibit potent biologic activity similar to that of LALF itself and could potentially be useful as a therapeutic agent. The effects of LALF, synthetic peptide LALF #28-54, polymyxin B (PmB), and a biologically inactive synthetic peptide were examined in several models. In vitro bactericidal activity was determined against Pseudomonas aeruginosa, and LPS-neutralizing capacity was determined via inhibition of LPS-induced tumor necrosis factor-alpha (TNF-alpha) secretion by RAW 264.7 cells. In vivo biologic activity was determined via pretreatment following which P aeruginosa endotoxemia or bacteremia was induced; serum TNF-alpha levels, bacterial clearance, and survival were assessed. LALF and LALF #28-54 exhibited potent in vitro bactericidal and LPS-neutralizing activity comparable to PmB (P bacterial clearance similar to that observed for LALF (P .1). These data demonstrate that peptide LALF #28-54 retained the LPS-neutralizing and bactericidal biologic activity of LALF but failed to protect during overwhelming P aeruginosa bacteremia, perhaps due to short serum half-life.

  14. Nutritional Supplement of Hatchery Eggshell Membrane Improves Poultry Performance and Provides Resistance against Endotoxin Stress.

    Science.gov (United States)

    Makkar, S K; Rath, N C; Packialakshmi, B; Zhou, Z Y; Huff, G R; Donoghue, A M

    2016-01-01

    Eggshells are significant part of hatchery waste which consist of calcium carbonate crust, membranes, and proteins and peptides of embryonic origins along with other entrapped contaminants including microbes. We hypothesized that using this product as a nutritional additive in poultry diet may confer better immunity to the chickens in the paradigm of mammalian milk that enhances immunity. Therefore, we investigated the effect of hatchery eggshell membranes (HESM) as a short term feed supplement on growth performance and immunity of chickens under bacterial lipopolysaccharide (LPS) challenged condition. Three studies were conducted to find the effect of HESM supplement on post hatch chickens. In the first study, the chickens were fed either a control diet or diets containing 0.5% whey protein or HESM as supplement and evaluated at 5 weeks of age using growth, hematology, clinical chemistry, plasma immunoglobulins, and corticosterone as variables. The second and third studies were done to compare the effects of LPS on control and HESM fed birds at 5 weeks of age following at 4 and 24 h of treatment where the HESM was also sterilized with ethanol to deplete bacterial factors. HESM supplement caused weight gain in 2 experiments and decreased blood corticosterone concentrations. While LPS caused a significant loss in body weight at 24 h following its administration, the HESM supplemented birds showed significantly less body weight loss compared with the control fed birds. The WBC, heterophil/lymphocyte ratio, and the levels of IgG were low in chickens fed diets with HESM supplement compared with control diet group. LPS challenge increased the expression of pro-inflammatory cytokine gene IL-6 but the HESM fed birds showed its effect curtailed, also, which also, favored the up-regulation of anti-inflammatory genes compared with control diet fed chickens. Post hatch supplementation of HESM appears to improve performance, modulate immunity, and increase resistance of

  15. Escin attenuates acute lung injury induced by endotoxin in mice.

    Science.gov (United States)

    Xin, Wenyu; Zhang, Leiming; Fan, Huaying; Jiang, Na; Wang, Tian; Fu, Fenghua

    2011-01-18

    Endotoxin causes multiple organ dysfunctions, including acute lung injury (ALI). The current therapeutic strategies for endotoxemia are designed to neutralize one or more of the inflammatory mediators. Accumulating experimental evidence suggests that escin exerts anti-inflammatory and anti-edematous effects. The aim of this study was to evaluate the effect of escin on ALI induced by endotoxin in mice. ALI was induced by injection of lipopolysaccharide (LPS) intravenously. The mice were given dexamethasone or escin before injection of LPS. The mortality rate was recorded. Tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β) and nitric oxide (NO) were measured. Pulmonary superoxide dismutase (SOD), glutathione peroxidase (GPx) activity, glutathione (GSH), malondialdehyde (MDA) contents, and myeloperoxidase (MPO) activity were also determined. The expression of glucocorticoid receptor (GR) level was detected by Western blotting. Pretreatment with escin could decrease the mortality rate, attenuate lung injury resulted from LPS, down-regulate the level of the inflammation mediators, including NO, TNF-α, and IL-1β, enhance the endogenous antioxidant capacity, and up-regulating the GR expression in lung. The results suggest that escin may have potent protective effect on the LPS-induced ALI by inhibiting of the inflammatory response, and its mechanism involves in up-regulating the GR and enhancing the endogenous antioxidant capacity. Copyright © 2010 Elsevier B.V. All rights reserved.

  16. Detection of microorganisms, endotoxins and aluminum in mobile dialysis services

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    Priscila Rodrigues de Jesus

    2017-11-01

    Full Text Available Hemodialysis water and dialysates are fundamental in the treatment of kidney disease. During just one hemodialysis session, 120 liters of dialysate are consumed. Thus, it is essential that the parameters of chemical and microbiological quality of the fluids used in dialysis systems are carefully observed. In this study, water samples were collected at 12 hospitals in the state of Rio de Janeiro. The samples were obtained at three points of fluid reservoirs: pre-, post-osmosis and dialysis solution. After collection, colony forming units (CFU, total coliforms and Escherichia coli 100 mL-1 were quantified. Later, isolated colonies and endotoxin content were identified by biochemical assays. Data about total aluminum levels per sample (mg L-1 were also obtained. Samples of all mobile dialysis services and points of collection were contaminated above the levels set out by national laws, in particular by Pseudomonas aeruginosa. Endotoxin levels were also above the recommended by current legislation (> 0.25 EU mL-1. Only three samples contained detectable levels of aluminum, which were found to be above the recommended values for the corresponding resolution (0.01 mg L-1. Finally, there were no observable amounts of total coliforms and E. coli 100 mL-1 sample. The data from this study are an important step forward in the standardization and control of chemical/microbiological quality of mobile dialysis services.

  17. Comparison of bacterial culture and qPCR testing of rectal and pen floor samples as diagnostic approaches to detect enterotoxic Escherichia coli in nursery pigs

    DEFF Research Database (Denmark)

    Weber, N. R.; Nielsen, J. P.; Hjulsager, Charlotte Kristiane

    2017-01-01

    Enterotoxigenic E. coli (ETEC) are a major cause of diarrhoea in weaned pigs. The objective of this study was to evaluate the agreement at pen level among three different diagnostic approaches for the detection of ETEC in groups of nursery pigs with diarrhoea. The diagnostic approaches used were......: bacterial culturing of faecal samples from three pigs (per pen) with clinical diarrhoea and subsequent testing for virulence genes in E. coli isolates; bacterial culturing of pen floor samples and subsequent testing for virulence genes in E. coli isolates; qPCR testing of pen floor samples in order...... to determine the quantity of F18 and F4 genes. The study was carried out in three Danish pig herds and included 31 pens with a pen-level diarrhoea prevalence of > 25%, as well as samples from 93 diarrhoeic nursery pigs from these pens. All E. coli isolates were analysed by PCR and classified as ETEC when genes...

  18. Measurement of operative plasma endotoxin levels in jaundiced and non-jaundiced patients.

    Science.gov (United States)

    Pain, J A; Bailey, M E

    1987-01-01

    A study of portal plasma endotoxin levels was performed using a chromogenic limulus amoebocyte lysate (LAL) assay. The assay proved sensitive and reproducible. In only 1 of 25 healthy subjects was the systemic plasma endotoxin level above 100 pg/ml (equivalent Escherichia coli 0111B4). In 30 non-jaundiced patients undergoing surgery the mean (+SEM) portal plasma endotoxin level (60 + 9 pg/ml) was significantly higher (p less than 0.05) than the mean level in the systemic blood (46 + 6 pg/ml), supporting the concept of endotoxin absorption from the intestine into the portal blood. In 20 patients with obstructive jaundice undergoing surgery 42% of portal, 45% of inferior mesenteric and 35% of systemic venous plasma endotoxin levels were above 100 pg/ml. There were significantly higher levels in the portal (p less than 0.05) and inferior mesenteric (p less than 0.05) compared with the systemic blood. Neither the presence of malignancy nor the duration of surgery appeared to influence endotoxin absorption. The significance of raised plasma endotoxin levels in obstructive jaundice is discussed.

  19. Importance of the personal endotoxin cloud in school-age children with asthma.

    Science.gov (United States)

    Rabinovitch, Nathan; Liu, Andrew H; Zhang, Lening; Rodes, Charles E; Foarde, Karin; Dutton, Steven J; Murphy, James R; Gelfand, Erwin W

    2005-11-01

    A number of studies have observed associations between the amount of endotoxin in urban dust and chronic asthma severity, but a direct relationship between personal exposure to household endotoxin and acute asthma worsening has not yet been defined. We sought to investigate the relationship between day-to-day changes in personal endotoxin exposure and asthma severity. In the winter and spring of 1999 through 2000, endotoxin exposures were monitored in asthmatic schoolchildren by using portable, as opposed to stationary, monitors designed to measure inhalable and respirable particulate matter less than or equal to 2.5 and 10 microm in diameter. Children were followed with daily measurements of FEV(1) and asthma symptoms. Over a 24-hour period, median daily personal endotoxin exposures ranged from 0.08 EU/m(3) (measured at a particulate matter size range Personal exposures were significantly (P personal activities might be better correlated with disease severity. Increases in personal endotoxin exposures were associated with decreased FEV(1) values and increased symptoms. These findings demonstrate the importance of using personal monitoring to both measure and correlate endotoxin exposure with asthma severity.

  20. In vitro activity of tigecycline, a new glycylcycline, tested against 1,326 clinical bacterial strains isolated from Latin America

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    Ana C. Gales

    Full Text Available The in vitro activity of tigecycline (former GAR-936, a new semisynthetic tetracycline, was evaluated in comparison with tetracycline and other antimicrobial agents. MATERIAL AND METHODS: A total of 1,326 contemporary clinical isolates collected from the Latin American region were collected in 2000-2002 period and tested with microdilution broth according to the CLSI guidelines. The bacterial pathogens evaluated included Staphylococcus aureus (505, Streptococcus pneumoniae (269, coagulase-negative staphylococci (CoNS; 227, Haemophilus influenzae (129, Enterococcus spp. (80, Moraxella catarrhalis (54, beta-haemolytic streptococci (28, viridans group streptococci (26, and Neisseria meningitidis (8 RESULTS:Tigecycline demonstrated excellent activity against all Gram-positive cocci, with 90% of penicillin-resistant S. pneumoniae strains being inhibited at 0.12 µg/mL, while the same isolates had an MIC90 of > 16 µg/mL for tetracycline. All Enterococcus spp. were inhibited at 0.25 µg/mL of tigecycline. Tigecycline (MIC50, 0.25 µg/mL was eight-fold more potent than minocycline (MIC50, 2 µg/mL against oxacillin-resistant S. aureus (ORSA; all ORSA were inhibited at < 2 µg/mL of tigecycline. Tigecycline demonstrated excellent activity (MIC50, 0.5 µg/mL against CoNS with reduced susceptibility to teicoplanin (MIC, 16 µg/mL. Tigecycline also showed high potency against respiratory pathogens such as M. catarrhalis (MIC50, 0.12 µg/mL and H. influenzae (MIC50, 0.5 µg/mL. No tigecycline resistant isolates were detected when the proposed susceptible breakpoints (< 4 µg/mL was applied. CONCLUSIONS: This results indicate that tigecycline has potent in vitro activity against clinically important pathogenic bacteria, including Gram-positive isolates resistant to both tetracycline and minocycline.

  1. Dietary oil composition differentially modulates intestinal endotoxin transport and postprandial endotoxemia

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    Mani Venkatesh

    2013-01-01

    Full Text Available Abstract Background Intestinal derived endotoxin and the subsequent endotoxemia can be considered major predisposing factors for diseases such as atherosclerosis, sepsis, obesity and diabetes. Dietary fat has been shown to increase postprandial endotoxemia. Therefore, the aim of this study was to assess the effects of different dietary oils on intestinal endotoxin transport and postprandial endotoxemia using swine as a model. We hypothesized that oils rich in saturated fatty acids (SFA would augment, while oils rich in n-3 polyunsaturated fatty acids (PUFA would attenuate intestinal endotoxin transport and circulating concentrations. Methods Postprandial endotoxemia was measured in twenty four pigs following a porridge meal made with either water (Control, fish oil (FO, vegetable oil (VO or coconut oil (CO. Blood was collected at 0, 1, 2, 3 and 5 hours postprandial and measured for endotoxin. Furthermore, ex vivo ileum endotoxin transport was assessed using modified Ussing chambers and intestines were treated with either no oil or 12.5% (v/v VO, FO, cod liver oil (CLO, CO or olive oil (OO. Ex vivo mucosal to serosal endotoxin transport permeability (Papp was then measured by the addition of fluorescent labeled-lipopolysaccharide. Results Postprandial serum endotoxin concentrations were increased after a meal rich in saturated fatty acids and decreased with higher n-3 PUFA intake. Compared to the no oil control, fish oil and CLO which are rich in n-3 fatty acids reduced ex vivo endotoxin Papp by 50% (P  Conclusion Overall, these results indicate that saturated and n-3 PUFA differentially regulate intestinal epithelial endotoxin transport. This may be associated with fatty acid regulation of intestinal membrane lipid raft mediated permeability.

  2. The expression of endotoxic activity in the Limulus test as compared to cytokine production in immune cells.

    Science.gov (United States)

    Brandenburg, Klaus; Howe, Jörg; Gutsman, Thomas; Garidel, Patrick

    2009-01-01

    Lipopolysaccharides (LPS, endotoxins) belong to the strongest elicitors of the mammalian immune system due to the induction of a series of cytokines such as tumor-necrosis-factor-alpha (TNFalpha) in immunocompetent cells like mononuclear cells. Since the effects of LPS on human health may be pathologically at too high concentrations (e.g., septic shock syndrome), it is of uttermost importance to have a reliable assay for measuring the concentrations of endotoxins in vitro and in vivo (human body fluids). The activation of the clotting cascade from the horseshoe crab (Limulus polyphemus), the Limulus amoebocyte lysate test (LAL), has been the standard and most sensitive assay to detect bacterial endotoxins. However, there are restrictions with this test. It was found in some clinical trials that the results from the LAL test did not correlate with the presence of bacteremia due to Gram-negative organisms or with the mortality but correlated with the presence of fungal bloodstream infections. This resulted from the fact that the LAL assay does not only respond to bacterial endotoxins but is activated also by (1-->3)-beta-D-glucan. Furthermore, in extensive studies the structural requirements for activation of the LAL test were analyzed, and it was found that the LAL activity correlated with pyrogenicity but not with activation of the complement cascade. Furthermore, there was no correlation of the LAL activity with cytokine expression (for example tumor-necrosis-factor-alpha and interleulkins-1 and 6) in mononuclear cells when the 4/2 acyl chain pattern of enterobacterial lipid A was changed, or when the cytokine production induced by LPS from various different species in the whole blood assay was compared with the response from the LAL test. To clarify the questions raised by the different experimental findings, data from literature are summarized to get a more closer insight where the Limulus test confidentially monitors the endotoxicity of LPS and other compounds

  3. A low concentration of ethanol reduces the chemiluminescence of human granulocytes and monocytes but not the tumor necrosis factor alpha production by monocytes after endotoxin stimulation

    DEFF Research Database (Denmark)

    Parlesak, Alexandr; Diedrich, J. P.; Schäfer, Christian

    1998-01-01

    necrosis factor alpha (TNF-alpha) from Mphi. Further, the efficiency of ethanol to inactivate chemically generated ROS was tested. Significant stimulation of ROS release occurred at endotoxin concentrations of 1 ng/ml or higher in both PMNs and Mphi. Ethanol significantly suppressed the formation of ROS...... identical (6 to 8 ng/ml) in both PMNs and Mphi, independent of the presence of ethanol. In contrast to ROS formation, ethanol had no effect on the amount of TNF-alpha produced by endotoxin-stimulated Mphi. Ethanol was shown to be unable to decrease the levels of chemically generated ROS under physiological......The ability of polymorphonuclear neutrophils (PMNs) and monocytes (Mphi) to produce reactive oxygen species (ROS) has been related closely to their potential in the killing of microorganisms. Ethanol has been shown to impair the generation of ROS in these phagocytes after stimulation with some...

  4. Crystal structure of an endotoxin-neutralizing protein from the horseshoe crab, Limulus anti-LPS factor, at 1.5 A resolution.

    Science.gov (United States)

    Hoess, A; Watson, S; Siber, G R; Liddington, R

    1993-09-01

    Lipopolysaccharide (LPS), or endotoxin, is the major mediator of septic shock, a serious complication of Gram-negative bacterial infections in humans. Molecules that bind LPS and neutralize its biological effects or enhance its clearance could have important clinical applications. Limulus anti-LPS factor (LALF) binds LPS tightly, and, in animal models, reduces mortality when administered before or after LPS challenge or bacterial infection. Here we present the high resolution structure of a recombinant LALF. It has a single domain consisting of three alpha-helices packed against a four-stranded beta-sheet. The wedge-shaped molecule has a striking charge distribution and amphipathicity that suggest how it can insert into membranes. The binding site for LPS probably involves an extended amphipathic loop, and we propose that two mammalian LPS-binding proteins will have a similar loop. The amphipathic loop structure may be used in the design of molecules with therapeutic properties against septic shock.

  5. In vitro evaluation of the action of irrigating solutions associated with intracanal medications on Escherichia coli and its endotoxin in root canals

    Directory of Open Access Journals (Sweden)

    Lilian Eiko Maekawa

    2011-04-01

    Full Text Available OBJECTIVE: The purpose of this study was to evaluate the effcacy of auxiliary chemical substances and intracanal medications on Escherichia coli and its endotoxin in root canals. MATERIAL AND METHODS: Teeth were contaminated with a suspension of E. coli for 14 days and divided into 3 groups according to the auxiliary chemical substance used: G1 2.5% sodium hypochlorite (NaOCl; G2 2% chlorhexidine gel (CLX; G3 pyrogenfree solution. After, these groups were subdivided according to the intracanal medication (ICM: A Calcium hydroxide paste (Calen®, B polymyxin B, and C Calcium hydroxide paste+2% CLX gel. For the control group (G4, pyrogen-free saline solution was used without application of intracanal medication. Samples of the root canal content were collected immediately after biomechanical preparation (BMP, at 7 days after BMP, after 14 days of intracanal medication activity, and 7 days after removal of intracanal medication. The following aspects were evaluated for all collections: a antimicrobial activity; b quantifcation of endotoxin by the Limulus Amebocyte Lysate test (LAL. Results were analyzed by the Kruskal-Wallis and Dunn's tests at 5% signifcance level. RESULTS: The 2.5% NaOCl and CLX were able to eliminate E. coli from root canal lumen and reduced the amount of endotoxin compared to saline. CONCLUSIONS: It was concluded that 2.5% NaOCl and CLX were effective in eliminating E. coli. Only the studied intracanal medications were to reduce the amount of endotoxin present in the root canals, regardless of the irrigant used.

  6. Multilevel correlations in the biological phosphorus removal process: From bacterial enrichment to conductivity-based metabolic batch tests and polyphosphatase assays.

    Science.gov (United States)

    Weissbrodt, David G; Maillard, Julien; Brovelli, Alessandro; Chabrelie, Alexandre; May, Jonathan; Holliger, Christof

    2014-12-01

    Enhanced biological phosphorus removal (EBPR) from wastewater relies on the preferential selection of active polyphosphate-accumulating organisms (PAO) in the underlying bacterial community continuum. Efficient management of the bacterial resource requires understanding of population dynamics as well as availability of bioanalytical methods for rapid and regular assessment of relative abundances of active PAOs and their glycogen-accumulating competitors (GAO). A systems approach was adopted here toward the investigation of multilevel correlations from the EBPR bioprocess to the bacterial community, metabolic, and enzymatic levels. Two anaerobic-aerobic sequencing-batch reactors were operated to enrich activated sludge in PAOs and GAOs affiliating with "Candidati Accumulibacter and Competibacter phosphates", respectively. Bacterial selection was optimized by dynamic control of the organic loading rate and the anaerobic contact time. The distinct core bacteriomes mainly comprised populations related to the classes Betaproteobacteria, Cytophagia, and Chloroflexi in the PAO enrichment and of Gammaproteobacteria, Alphaproteobacteria, Acidobacteria, and Sphingobacteria in the GAO enrichment. An anaerobic metabolic batch test based on electrical conductivity evolution and a polyphosphatase enzymatic assay were developed for rapid and low-cost assessment of the active PAO fraction and dephosphatation potential of activated sludge. Linear correlations were obtained between the PAO fraction, biomass specific rate of conductivity increase under anaerobic conditions, and polyphosphate-hydrolyzing activity of PAO/GAO mixtures. The correlations between PAO/GAO ratios, metabolic activities, and conductivity profiles were confirmed by simulations with a mathematical model developed in the aqueous geochemistry software PHREEQC. © 2014 Wiley Periodicals, Inc.

  7. Exposure to household endotoxin and total and allergen-specific IgE in the US population

    International Nuclear Information System (INIS)

    Min, Kyoung-Bok; Min, Jin-Young

    2015-01-01

    Background: Although endotoxin has strong pro-inflammatory properties, endotoxin-allergy relationship in adults and children have been inconsistent. Objectives: We investigated the association between household endotoxin levels and total immunoglobulin E (IgE) or specific IgE in the US general population, classified into three age ranges: children/adolescent, adults, and older adults. Methods: We analyzed the 2005–2006 National Health and Nutrition Examination Surveys. A total of 5220 participants for whom serum IgE and household endotoxin data were available was included in the analyses. Results: Exposure to endotoxin reduced the risk for allergic sensitization, especially in specific IgE to plants (OR in Quartile 3 = 0.58; 95% CI = 0.44–0.76) and pets (OR in Quartile 3 = 0.62; 95% CI = 0.41–0.92), for children/adolescents. In contrast, the risk among adults and older adults increased with increasing endotoxin levels. Conclusions: Our findings suggest that the effect of endotoxin on allergic reaction is likely to depend on age. - Highlights: • Findings regarding the endotoxin-allergy relationship in adults and children are inconsistent. • We investigated the association of endotoxin with total and specific IgE in US population. • The association between endotoxin levels and allergic markers is likely to depend on age. • Exposure to endotoxin reduced the risk for allergic sensitization for children/adolescents. • The risk among adults and older adults increased with increasing endotoxin levels. - Exposure to endotoxin reduced the risk for allergic sensitization for children/adolescents, but decreased the risk among adults and older

  8. Inhalation toxicology models of endotoxin- and bioaerosol-induced inflammation.

    Science.gov (United States)

    Thorne, P S

    2000-11-02

    Inhalation toxicology studies in rodents have proven their usefulness for furthering our understanding of the causal agents, mechanisms, and pathology associated with exposures to environmental endotoxins and bioaerosols. Inhalation animal models are used to determine which components of a mixture are the most important toxicants for inducing the observed adverse outcome. They are used to obtain exposure-response relationships for allergens and pro-inflammatory agents to help elucidate disease mechanisms and contribute quantitative data to the risk assessment process. Inhalation models serve as important adjuncts to epidemiology studies and human exposure studies. They are also useful for establishing phenotype in studies of genetic polymorphisms and disease susceptibility and are widely applied for evaluation of safety and efficacy for potential therapeutic agents. In order to produce reliable data, rigorous exposure chamber design, aerosol generation systems, exposure quantitation and experimental protocols must be utilized.

  9. Glucose hydrogen breath test for small intestinal bacterial overgrowth in children with abdominal pain-related functional gastrointestinal disorders

    NARCIS (Netherlands)

    Korterink, Judith J.; Benninga, Marc A.; van Wering, Herbert M.; Deckers-Kocken, Judith M.

    2015-01-01

    A potential link between small intestinal bacterial overgrowth (SIBO) and abdominal pain-related functional gastrointestinal disorders (AP-FGID) has been suggested by symptom similarities and by the reported prevalence of SIBO in children with irritable bowel syndrome (IBS) and functional AP. The

  10. Determination of alkylation of bacterial DNA as a rapid test for toxicological evaluation of alkylating xenobiotic agents

    Energy Technology Data Exchange (ETDEWEB)

    Botzenhart, K.; Waldner-Sander, S.; Schweinsberg, F.

    1986-05-01

    Alkylated purine bases from hydrolized DNA can be separated by HPLC and quantified with a fluorescence detector. We applied this method to bacterial DNA. 7-methylguanine was detected after treatment of Serratia marcescens with iodoacetamide, dimethyl sulfate and with polluted air.

  11. High mortality rates occur in copper deficient rats exposed to a normally nonlethal endotoxin treatment

    Energy Technology Data Exchange (ETDEWEB)

    DiSilvestro, R.; Joseph, E.; Yang, F.L. (Ohio State Univ., Columbus (United States))

    1991-03-15

    Endotoxin hepatotoxicity is proposed to occur by processes which could be retarded by 3 copper enzymes: ceruloplasmin, Cu-Zn superoxide dismutase (SOD), and extracellular (EC) SOD. Weanling rats fed low copper for 40 days showed low activity levels of these enzymes, and a very high mortality rate 20 h after endotoxin injection. No rats fed adequate copper died from this treatment. In addition, serum transaminase activities, indicators of liver damage, were elevated by 3 h to a greater extent in the deficient rats than in the adequates. The high susceptibility to endotoxemia in the deficient rats was not associated with low hepatic glutathione, high liver malondialedhyde, nor restricted metallothionein induction 3 h after endotoxin injection. Endotoxin reduced serum EC SOD activities in adequate and deficient rats, but final values were lower in the latter. Studies on roles of specific copper enzymes in resistance to endotoxemia are currently underway.

  12. Allergen specific responses in cord and adult blood are differentially modulated in the presence of endotoxins

    DEFF Research Database (Denmark)

    Eiwegger, T.; Mayer, E.; Pedersen, Susanne Brix

    2008-01-01

    Background Endotoxins are common contaminants in allergen preparations and affect antigen-specific cellular responses. Distinct effects of endotoxin on cells in human umbilical cord and adult blood are poorly defined. Objectives To examine the effect of endotoxins in allergen preparations...... on cellular responses in human cord and peripheral blood (PB). Methods The endotoxin content in beta lactoglobulin (BLG), the peanut allergen Ara h 1 and the major birch pollen allergen Bet v 1 was assessed. Proliferation and cytokine response of mononuclear cells towards contaminated and lipopolysaccharide...... (LPS)-free allergens were evaluated at different time-points. Fractions of contaminated BLG were generated and assayed on their immuno-stimulatory capacity. The involvement of toll-like receptor (TLR) 2 and 4 was investigated by blocking antibodies and TLR-transfected human embryonic kidney cells...

  13. The role of endotoxin in the pathogenesis of acute bovine laminitis.

    Science.gov (United States)

    Boosman, R; Mutsaers, C W; Klarenbeek, A

    1991-07-01

    To study the possible role of endotoxin in the pathogenesis of bovine laminitis, local and systemic injections of endotoxin (E. coli 0111 B4) with different doses were given to three groups of four cows each. Clinical and haematologic parameters indicated an acute-phase response, including positive plasma ethanol gelation (soluble fibrin), the occurrence of fibrin degradation products and decreased thrombocyte counts. Local Shwartzman reactions were not evoked. Clinical examination of the claws and the gait of the animals revealed no signs of laminitis. However, on histopathological examination of the claw corium signs of laminitis such as vacuolisation of the Stratum basale, lymphocyte and leucocyte infiltration and thrombosis were found. These results indicate that endotoxin indeed may be involved in the pathogenesis of laminitis. For the development of a clinical acute laminitis model in cattle either another dosage, other toxins or factors in addition to the endotoxin used in this experiment are needed.

  14. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Science.gov (United States)

    2010-07-01

    ... thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens; exemption from the requirement... killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens is exempt from the...

  15. Effect of saccharides on growth, sporulation rate and δ-endotoxin ...

    African Journals Online (AJOL)

    sucrose, lactose and maltose) as carbon sources on growth and sporulation rate of Bacillus thuringiensis MPK13 as well as δ-endotoxin production was investigated using 400 ml shake flasks culture. Substantially high growth and sporulation ...

  16. Experimental study of 『PERSICAE SEMEN』 on the blood injected by Endotoxin in rats

    Directory of Open Access Journals (Sweden)

    Chang-Keun

    2005-06-01

    Full Text Available This study was performed to investigate the effects of 「Persicae Semen」(PS on the blood injected by Endotoxin in rats. The blood was induced by Endotoxin injection into the caudal vein of rats and PS group taken a measurement of RBC, Hb, Hct, Platelet, WBC, ESR, CRP. The results were obtained as follows: 1. RBC, Hb, Hct, Platelet, WBC were increased with statistical significance at PS group as compared with those of the control group. 2. ESR, CRP were decreased with statistical significance at PS group as compared with those of the control group. It is concluded that PS group has significant effects on the blood injected by Endotoxin in rats. Therefore, PS group seems to be applicable to the diseases related to Endotoxin in clinics.

  17. The emerging role of microRNA in regulation of endotoxin tolerance.

    LENUS (Irish Health Repository)

    Quinn, Edel M

    2012-05-01

    Endotoxin tolerance is a phenomenon where cells show reduced responsiveness toward repeated endotoxin stimulation. Regulation of tolerance occurs at multiple levels of the cell signaling cascade, and many of these levels are potentially regulated by miRNA, which are a class of small RNA that bind to mRNA to down-regulate gene expression at the post-transcriptional level. Roles have been identified for miR-146a, miR-221, miR-579, miR-125b, miR-155, let-7e, and miR-98 in regulating the TLR4 signaling pathway during the development of endotoxin tolerance at receptor, signaling pathway, and gene transcription and translational levels. miRNA represent exciting, new potential targets in attempts to exogenously modulate development of endotoxin tolerance.

  18. [Removal of oral Prevotella intermedia Endotoxin by octyl phenyl polyoxyethylene ether extraction method].

    Science.gov (United States)

    Wang, Ai-wu; Liu, Yan; Hu, Kong-xin; Cheng, Qian

    2012-12-01

    To investigate an effective purification method for removing endotoxin from Prevotella intermedia. The main protein ingredients of bacteria prepared from ammonium sulfate precipitation were further treated with octyl phenyl polyoxyethylene ether (Triton X-114), and then processed at 4°C, 37°C and 25°C. The obtained aqueous phase after at least two more cycle repeated operations was assayed for endotoxin by Western blotting, LAL-clotting method, in vitro cell stimulation and in vivo animal experiments. Western blotting and LAL-clotting method demonstrated that the reduction in endotoxin level was greater than 99.99% and recovery of the proteins after endotoxin removal was greater than 90% with Triton X-114 treatment for 3 cycles. The cytokines expression level was lower in both in vitro cell stimulation and in vivo animal experiments than in untreated group (P Prevotella intermedia.

  19. Altered hepatic vasopressin and alpha 1-adrenergic receptors after chronic endotoxin infusion

    International Nuclear Information System (INIS)

    Roth, B.L.; Spitzer, J.A.

    1987-01-01

    Sepsis and septic shock are complicated by a number of hemodynamic and metabolic aberrations. These include catecholamine refractoriness and altered glucose metabolism. Recently, a nonshock rat model of continuous endotoxin infusion via an implanted osmotic pump was developed that reproduces some of the metabolic and cardiovascular findings of human sepsis. By using this model, we have found a decreased number of hepatic plasma membrane alpha 1-adrenergic and [Arg8]vasopressin receptors in rats continuously infused with endotoxin. There was a significant decrease in [ 3 H]prazosin (35 +/- 7%) and [ 3 H] [Arg8]vasopressin (43 +/- 8%) receptors after 30 h of continuous endotoxin infusion with no change in affinity. The ability of norepinephrine to form the high-affinity complex with alpha 1-adrenergic receptors was not altered after chronic endotoxin infusion. The results are consistent with the concept that alterations in receptor number might underlie certain of the metabolic consequences of chronic sepsis

  20. Isolation and sequencing of the cryIC-like delta endotoxin gene from ...

    African Journals Online (AJOL)

    Isolation and sequencing of the cryIC-like delta endotoxin gene from Egyptian strains of Bacillus thuringiensis toxic against Lepidoptera. ME Elkashef, AM Heikal, MEDM Solliman, MI Kobeasy, HA El-Shemy ...

  1. Identification of Sources of Endotoxin Exposure as Input for Effective Exposure Control Strategies.

    Science.gov (United States)

    van Duuren-Stuurman, Birgit; Gröllers-Mulderij, Mariska; van de Runstraat, Annemieke; Duisterwinkel, Anton; Terwoert, Jeroen; Spaan, Suzanne

    2018-02-13

    Aim of the present study is to investigate the levels of endotoxins on product samples from potatoes, onions, and seeds, representing a relevant part of the agro-food industry in the Netherlands, to gather valuable insights in possibilities for exposure control measures early in the process of industrial processing of these products. Endotoxin levels on 330 products samples from companies representing the potato, onion, and seed (processing) industry (four potato-packaging companies, five potato-processing companies, five onion-packaging companies, and four seed-processing companies) were assessed using the Limulus Amboecyte Lysate (LAL) assay. As variation in growth conditions (type of soil, growth type) and product characteristics (surface roughness, dustiness, size, species) are assumed to influence the level of endotoxin on products, different types, and growth conditions were considered when collecting the samples. Additionally, waste material, rotten products, felt material (used for drying), and process water were collected. A large variation in the endotoxin levels was found on samples of potatoes, onions, and seeds (overall geometric standard deviation 17), in the range between 0.7 EU g-1 to 16400000 EU g-1. The highest geometric mean endotoxin levels were found in plant material (319600 EU g-1), followed by soil material (49100 EU g-1) and the outer side of products (9300 EU g-1), indicating that removal of plant and soil material early in the process would be an effective exposure control strategy. The high levels of endotoxins found in the limited number of samples from rotten onions indicate that these rotten onions should also be removed early in the process. Mean endotoxin levels found in waste material (only available for seed processing) is similar to the level found in soil material, although the range is much larger. On uncleaned seeds, higher endotoxin levels were found than on cleaned seeds, indicating that cleaning processes are important

  2. Analysis of the Cellular and Molecular Mechanisms Which Underlie Sensitivity to Bacterial Endotoxin and Early Tolerance

    Science.gov (United States)

    1992-06-24

    tachycardia, tachypnea, hypertriglyceridemia, thrombocytopenia, metabolic acidosis, acute renal failure, hepatic failure, acute respiratory distress...The symptomatology associated with endotoxemia was first noted in modem times in 1928 by Schwartzman, who first described the systemic disseminated...bilirubin, lactate (which indicates an ameliorating effect on metabolic acidosis), and to bring about an increase in the mean arterial pressure in balxxms

  3. Enhancement of Cell Attachment to a Substrate Coated with Oral Bacterial Endotoxin by Plasma Fibronectin

    Science.gov (United States)

    1983-01-01

    Cefl cuL- ture dishes. and the assuallption that each Because there asa slgnifiealt dilterelice ill cell attachnctlit (romn the conitrol atl 12.5...coated Culture dishes "~ henl the\\ groups t reated ssit h 5ff to f100 ng ml of "erFe incubated with plasmia li bronccli n tor fi bronec tin were F not sig

  4. Comparison Between the Polymyxins and Gentamicin in Preventing Endotoxin-Induced Intravascular Coagulation and Leukopenia

    Science.gov (United States)

    Corrigan, James J.; Bell, Bobbie M.

    1971-01-01

    Three antimicrobial agents were evaluated as to their ability to neutralize the toxic effects of endotoxin in rabbits. These consisted of two cyclic polypeptides, polymyxin B sulfate and colymycin M (sodium colistimethate), and an aminoglycoside, gentamicin sulfate. Polymyxin B regularly prevented endotoxin-induced leukopenia, thrombocytopenia, and disseminated intravascular coagulation. Colymycin M had similar activity but was not as effective as polymyxin B. Gentamicin demonstrated no neutralizing ability in this study. PMID:4343409

  5. Endotoxin concentration in poultry houses for laying hens kept in cages or in alternative housing systems

    OpenAIRE

    2011-01-01

    Abstract 1. Endotoxins as components of organic dust may have adverse effects on the respiratory health of workers in poultry buildings. The move towards more welfare-friendly housing systems for layers may increase worker exposure to air contaminants due to the use of litter. 2. The endotoxin concentrations in the inhalable fraction of airborne dust (below 100 ?m) from cage and alternative system henhouses (on-floor, free range and aviaries) were compared under both experiment...

  6. Branchial challenge of normal subjects with the endotoxin of Enterobacter agglomerans isolated from cotton dust.

    Science.gov (United States)

    Jamison, J P; Lowry, R C

    1986-05-01

    Endotoxin produced by a culture of Enterobacter agglomerans isolated from cotton dust was inhaled by 12 normal subjects. No significant airway constriction was obtained in doses equivalent to those experienced in a workshift in a dusty mill. There was a statistically significant difference between this result and the bronchoconstriction that had occurred after flax dust inhalation in the same subjects. It is suggested that Enterobacter agglomerans endotoxin is not the causative agent of the acute bronchoconstriction that follows inhalation of textile dust.

  7. Branchial challenge of normal subjects with the endotoxin of Enterobacter agglomerans isolated from cotton dust.

    OpenAIRE

    Jamison, J P; Lowry, R C

    1986-01-01

    Endotoxin produced by a culture of Enterobacter agglomerans isolated from cotton dust was inhaled by 12 normal subjects. No significant airway constriction was obtained in doses equivalent to those experienced in a workshift in a dusty mill. There was a statistically significant difference between this result and the bronchoconstriction that had occurred after flax dust inhalation in the same subjects. It is suggested that Enterobacter agglomerans endotoxin is not the causative agent of the a...

  8. A non-chromatographic method for the removal of endotoxins from bacteriophages.

    Science.gov (United States)

    Branston, Steven D; Wright, Jason; Keshavarz-Moore, Eli

    2015-08-01

    The Ff filamentous bacteriophages show potential as a new class of therapeutics, displaying utility in materials science as well as pharmaceutical applications. These phages are produced by the infection of E. coli, a Gram-negative bacterium which unavoidably sheds endotoxins into the extracellular space during growth. Since endotoxin molecules are highly immunoreactive, separation from the phage product is of critical importance, particularly those developed for human therapeutic use. The properties of M13, one of the Ff group, present a purification challenge chiefly because the standard scalable method for endotoxin removal from proteins-anion exchange chromatography-is not applicable due to pI similarity between the particles. This article examines the potential of polyethylene glycol (PEG)-NaCl precipitation as a scalable method for the separation of endotoxins from phage M13. Precipitation of M13 by 2% (w/v) PEG 6 000, 500 mM NaCl reduced endotoxin contamination of the phage product by 88%, but additional precipitation rounds did not maintain this proportional decrease. Dynamic light scattering was subsequently used to determine the effectiveness of a detergent to disassociate endotoxin molecules from M13. As a result, PEG-NaCl precipitation was supplemented with up to 2% (v/v) Triton X-100 to improve separation. A 5.7 log10 reduction in endotoxin concentration was achieved over three rounds of precipitation whilst retaining over 97% of the phage. This method compares favorably with the well-known ATPS (Triton X-114) technique for endotoxin removal from protein solutions. © 2015 Wiley Periodicals, Inc.

  9. Bacterial meningitis

    NARCIS (Netherlands)

    Roos, Karen L.; van de Beek, Diederik

    2010-01-01

    Bacterial meningitis is a neurological emergency. Empiric antimicrobial and adjunctive therapy should be initiated as soon as a single set of blood cultures has been obtained. Clinical signs suggestive of bacterial meningitis include fever, headache, meningismus, vomiting, photophobia, and an

  10. [Acute bacterial meningitis with soluble antigen detected by latex particle agglutination tests at the Sourô-Sanou University Hospital of Bobo-Dioulasso (Burkina Faso)].

    Science.gov (United States)

    Ouédraogo, S M; Yaméogo, T M; Kyelem, C G; Poda, G E A; Ouédraogo, N F; Millogo, A; Ouédraogo, A; Ouédraogo-Traoré, A; Drabo, Y J

    2012-01-01

    Acute bacterial meningitis constitutes a major public health problem in Burkina Faso, in part because of its high lethality rate, estimated in 2004 at 17.5%. Failure to confirm suspected cases of meningitis results in overestimating reported cases and incorrectly treating false positives. The latex particle agglutination test is a diagnostic alternative that overcomes these limitations. Determine the bacteriological and therapeutic profile as well as the course of cases of acute meningitis confirmed by the latex agglutination test at Sourô-Sanou University Hospital. This prospective longitudinal study took place over a one-year period (2008 to 2009). Data were collected from clinical and laboratory records. The diagnosis of meningitis was confirmed by testing for specific soluble antigens in the spinal fluid. We used the Pastorex(™) Meningitis Kit for that purpose. The threshold of significance selected for our study was 0.05. In all, 457 samples of spinal fluid from patients with suspected acute bacterial meningitis were analyzed and the latex test was performed in 438 of these samples: 154 (35.2%) were positive. The average age of our cases confirmed by the latex test was 13.2 ± 4.2 years old. This test confirmed more cases than any other method of identification. The therapeutic strategy used from one to four treatment agents. Streptococcus pneumoniae was the most virulent and the most lethal pathogen, with a 64.7% lethality rate. The earliness of the consultation and the treatment of the bacterial meningitis seem to have a positive effect on the course of disease.

  11. Cloricromene, a coumarine derivative, protects against lethal endotoxin shock in rats.

    Science.gov (United States)

    Squadrito, F; Altavilla, D; Campo, G M; Calapai, G; Ioculano, M; Zingarelli, B; Saitta, A; Prosdocimi, M; Caputi, A P

    1992-01-14

    Endotoxin shock was induced in male rats by an intravenous (i.v.) injection of Salmonella enteriditis lipopolysaccharide (LPS; 20 mg/kg i.v.). Survival rate, macrophage and serum tumor necrosis factor (TNF-alpha), mean arterial blood pressure (MAP) and white blood cell count were then evaluated. Furthermore the in vitro effect of cloricromene on peritoneal macrophage phagocytosis and TNF-alpha release by primed peritoneal macrophages was investigated. LPS administration caused animal death (0% survival 24 h after endotoxin challenge), hypotension, marked leukopenia and increased the levels of TNF-alpha in both serum and macrophage supernatants. Cloricromene administration (0.5, 1 and 2 mg/kg i.v. 15 min after endotoxin) protected against LPS-induced lethality (100% survival rate 24 h after endotoxin challenge), reverted LPS-induced hypotension and leukopenia, and decreased TNF-alpha in both serum and macrophage supernatants. Finally, cloricromene, added in vitro to peritoneal macrophages collected from endotoxin-treated rats increased macrophage phagocytosis and reduced TNF-alpha formation by activated mononuclear phagocytes. Our data suggest that cloricromene increases survival rate in endotoxin shock through an inhibition of TNF-alpha production.

  12. Removal of endotoxin from deionized water using micromachined silicon nanopore membranes

    International Nuclear Information System (INIS)

    Smith, Ross A; Fissell, William H; Fleischman, Aaron J; Roy, Shuvo; Goldman, Ken; Zorman, Christian A

    2011-01-01

    Endotoxins are lipopolysaccharide components of the cell membrane of Gram-negative bacteria that trigger the body's innate immune system and can cause shock and death. Water for medical therapy, including parenteral and dialysate solutions, must be free of endotoxin. This purity is challenging to achieve as many Gram-negative bacteria are endemic in the environment, and can thrive in harsh, nutrient-poor conditions. Current methods for removing endotoxin include distillation and reverse osmosis, both of which are resource intensive processes. Membranes that present an absolute barrier to macromolecular passage may be capable of delivering pure water for biomedical applications. In this work, endotoxin has been filtered from aqueous solutions using silicon nanopore membranes (SNMs) with monodisperse pore size distributions. SNMs with critical pore sizes between 26 and 49 nm were challenged with solutions of deionized water spiked with endotoxin and with Pseudomonas cepacia. The filtrate produced by the SNM from Pseudomonas-contaminated water had <1.0 endotoxin unit (EU) ml −1 , which meets standards for dialysate purity. This approach suggests a technique for single-step cleanup of heavily contaminated water that may be suitable for field or clinical use

  13. Cytotoxicity Analysis of Three Bacillus thuringiensis Subsp. israelensis δ-Endotoxins towards Insect and Mammalian Cells

    Science.gov (United States)

    Teixeira Corrêa, Roberto Franco; Ardisson-Araújo, Daniel Mendes Pereira; Monnerat, Rose Gomes; Ribeiro, Bergmann Morais

    2012-01-01

    Three members of the δ-endotoxin group of toxins expressed by Bacillus thuringiensis subsp. israelensis, Cyt2Ba, Cry4Aa and Cry11A, were individually expressed in recombinant acrystalliferous B. thuringiensis strains for in vitro evaluation of their toxic activities against insect and mammalian cell lines. Both Cry4Aa and Cry11A toxins, activated with either trypsin or Spodoptera frugiperda gastric juice (GJ), resulted in different cleavage patterns for the activated toxins as seen by SDS-PAGE. The GJ-processed proteins were not cytotoxic to insect cell cultures. On the other hand, the combination of the trypsin-activated Cry4Aa and Cry11A toxins yielded the highest levels of cytotoxicity to all insect cells tested. The combination of activated Cyt2Ba and Cry11A also showed higher toxic activity than that of toxins activated individually. When activated Cry4Aa, Cry11A and Cyt2Ba were used simultaneously in the same assay a decrease in toxic activity was observed in all insect cells tested. No toxic effect was observed for the trypsin-activated Cry toxins in mammalian cells, but activated Cyt2Ba was toxic to human breast cancer cells (MCF-7) when tested at 20 µg/mL. PMID:23029407

  14. Cytotoxicity analysis of three Bacillus thuringiensis subsp. israelensis δ-endotoxins towards insect and mammalian cells.

    Directory of Open Access Journals (Sweden)

    Roberto Franco Teixeira Corrêa

    Full Text Available Three members of the δ-endotoxin group of toxins expressed by Bacillus thuringiensis subsp. israelensis, Cyt2Ba, Cry4Aa and Cry11A, were individually expressed in recombinant acrystalliferous B. thuringiensis strains for in vitro evaluation of their toxic activities against insect and mammalian cell lines. Both Cry4Aa and Cry11A toxins, activated with either trypsin or Spodoptera frugiperda gastric juice (GJ, resulted in different cleavage patterns for the activated toxins as seen by SDS-PAGE. The GJ-processed proteins were not cytotoxic to insect cell cultures. On the other hand, the combination of the trypsin-activated Cry4Aa and Cry11A toxins yielded the highest levels of cytotoxicity to all insect cells tested. The combination of activated Cyt2Ba and Cry11A also showed higher toxic activity than that of toxins activated individually. When activated Cry4Aa, Cry11A and Cyt2Ba were used simultaneously in the same assay a decrease in toxic activity was observed in all insect cells tested. No toxic effect was observed for the trypsin-activated Cry toxins in mammalian cells, but activated Cyt2Ba was toxic to human breast cancer cells (MCF-7 when tested at 20 µg/mL.

  15. Endotoxins potentiate COX-2 and RANKL expression in compressed PDL cells.

    Science.gov (United States)

    Römer, Piero; Köstler, Josef; Koretsi, Vasiliki; Proff, Peter

    2013-12-01

    This study aims to demonstrate in vitro the synergistic effect of orthodontic forces and periodontal pathogens on cyclooxygenase-2 regulation and the subsequent receptor activator of nuclear factor kappa-B ligand (RANKL) production from periodontal ligament (PDL) cells. In comparison to a control group, three experimental groups were formed from human primary PDL cells stressed with compressive forces, bacterial endotoxins, or a combination of both. Gene expression of cyclooxygenase-2 and RANKL was analysed with RT real-time PCR. The prostaglandin E2 production was determined with ELISA. A co-culture of PDL cells and an osteoclast-progenitor cell line was used in order to demonstrate the osteoclast formation effect caused by the simultaneous combined stress. The simultaneous combined stress resulted in a 56-fold up-regulation of cyclooxygenase-2 gene expression with a subsequent noticeable rise in the prostaglandin E2 in the culture medium. The RANKL/osteoprotegerin gene expression ratio was 50-fold up-regulated and the osteoclast formation assay revealed 153.5 ± 15.7 tartrate-resistant acid phosphatase (TRAP)-positive cells per well compared with 42.3 ± 3.8 TRAP-positive cells per well of the control group. The synergistic action of periodontal pathogens and orthodontic forces leads to an increased expression of cyclooxygenase-2 from PDL cells that intensify the RANKL production which in turn induces osteoclast differentiation and subsequent osteoclastogenesis. The present study puts an emphasis on the detrimental effect of orthodontic forces on patients with an active periodontal disease by underlining the significance of cyclooxygenase-2 activity and RANKL binding on the osteoclastogenesis process.

  16. A new improved protocol for in vitro intratubular dentinal bacterial contamination for antimicrobial endodontic tests: standardization and validation by confocal laser scanning microscopy

    Directory of Open Access Journals (Sweden)

    Flaviana Bombarda de ANDRADE

    2015-01-01

    Full Text Available Objectives To compare three methods of intratubular contamination that simulate endodontic infections using confocal laser scanning microscopy (CLSM. Material and Methods Two pre-existing models of dentinal contamination were used to induce intratubular infection (groups A and B. These methods were modified in an attempt to improve the model (group C. Among the modifications it may be included: specimen contamination for five days, ultrasonic bath with BHI broth after specimen sterilization, use of E. faecalis during the exponential growth phase, greater concentration of inoculum, and two cycles of centrifugation on alternate days with changes of culture media. All specimens were longitudinally sectioned and stained with of LIVE/DEAD® for 20 min. Specimens were assessed using CLSM, which provided images of the depth of viable bacterial proliferation inside the dentinal tubules. Additionally, three examiners used scores to classify the CLSM images according to the following parameters: homogeneity, density, and depth of the bacterial contamination inside the dentinal tubules. Kruskal-Wallis and Dunn’s tests were used to evaluate the live and dead cells rates, and the scores obtained. Results The contamination scores revealed higher contamination levels in group C when compared with groups A and B (p0.05. The volume of live cells in group C was higher than in groups A and B (p<0.05. Conclusion The new protocol for intratubular infection resulted in high and uniform patterns of bacterial contamination and higher cell viability in all specimens when compared with the current methods.

  17. A new improved protocol for in vitro intratubular dentinal bacterial contamination for antimicrobial endodontic tests: standardization and validation by confocal laser scanning microscopy.

    Science.gov (United States)

    Andrade, Flaviana Bombarda de; Arias, Marcela Paola Castro; Maliza, Amanda Garcia Alves; Duarte, Marco Antonio Hungaro; Graeff, Márcia Sirlene Zardin; Amoroso-Silva, Pablo Andrés; Midena, Raquel Zanin; Moraes, Ivaldo Gomes de

    2015-01-01

    To compare three methods of intratubular contamination that simulate endodontic infections using confocal laser scanning microscopy (CLSM). Two pre-existing models of dentinal contamination were used to induce intratubular infection (groups A and B). These methods were modified in an attempt to improve the model (group C). Among the modifications it may be included: specimen contamination for five days, ultrasonic bath with BHI broth after specimen sterilization, use of E. faecalisduring the exponential growth phase, greater concentration of inoculum, and two cycles of centrifugation on alternate days with changes of culture media. All specimens were longitudinally sectioned and stained with of LIVE/DEAD for 20 min. Specimens were assessed using CLSM, which provided images of the depth of viable bacterial proliferation inside the dentinal tubules. Additionally, three examiners used scores to classify the CLSM images according to the following parameters: homogeneity, density, and depth of the bacterial contamination inside the dentinal tubules. Kruskal-Wallis and Dunn's tests were used to evaluate the live and dead cells rates, and the scores obtained. The contamination scores revealed higher contamination levels in group C when compared with groups A and B (p0.05). The volume of live cells in group C was higher than in groups A and B (p<0.05). The new protocol for intratubular infection resulted in high and uniform patterns of bacterial contamination and higher cell viability in all specimens when compared with the current methods.

  18. Long-term interdisciplinary therapy reduces endotoxin level and insulin resistance in obese adolescents.

    Science.gov (United States)

    Lira, Fábio S; Rosa, Jose C; Pimentel, Gustavo D; Santos, Ronaldo V; Carnier, June; Sanches, Priscila L; de Piano, Aline; de Souza, Claudio T; Tock, Lian; Tufik, Sergio; de Mello, Marco T; Seelaender, Marília; Oller do Nascimento, Claudia M; Oyama, Lila M; Dâmaso, Ana R

    2012-09-18

    The purpose of the present study was to assess the dietary fat intake, glucose, insulin, Homeostasis model assessment for insulin resistance HOMA-IR, and endotoxin levels and correlate them with adipokine serum concentrations in obese adolescents who had been admitted to long-term interdisciplinary weight-loss therapy. The present study was a longitudinal clinical intervention of interdisciplinary therapy. Adolescents (n = 18, aged 15-19 y) with a body mass index > 95th percentile were admitted and evaluated at baseline and again after 1 year of interdisciplinary therapy. We collected blood samples, and IL-6, adiponectin, and endotoxin concentrations were measured by ELISA. Food intake was measured using 3-day diet records. In addition, we assessed glucose and insulin levels as well as the homeostasis model assessment for insulin resistance (HOMA-IR). The most important finding from the present investigation was that the long-term interdisciplinary lifestyle therapy decreased dietary fat intake and endotoxin levels and improved HOMA-IR. We observed positive correlations between dietary fat intake and endotoxin levels, insulin levels, and the HOMA-IR. In addition, endotoxin levels showed positive correlations with IL-6 levels, insulin levels and the HOMA-IR. Interestingly, we observed a negative correlation between serum adiponectin and both dietary fat intake and endotoxin levels. The present results indicate an association between dietary fat intake and endotoxin level, which was highly correlated with a decreased pro-inflammatory state and an improvement in HOMA-IR. In addition, this benefits effect may be associated with an increased adiponectin level, which suggests that the interdisciplinary therapy was effective in improving inflammatory pathways.

  19. Long-term interdisciplinary therapy reduces endotoxin level and insulin resistance in obese adolescents

    Directory of Open Access Journals (Sweden)

    Lira Fábio S

    2012-09-01

    Full Text Available Abstract Aim The purpose of the present study was to assess the dietary fat intake, glucose, insulin, Homeostasis model assessment for insulin resistance HOMA-IR, and endotoxin levels and correlate them with adipokine serum concentrations in obese adolescents who had been admitted to long-term interdisciplinary weight-loss therapy. Design The present study was a longitudinal clinical intervention of interdisciplinary therapy. Adolescents (n = 18, aged 15–19 y with a body mass index > 95th percentile were admitted and evaluated at baseline and again after 1 year of interdisciplinary therapy. We collected blood samples, and IL-6, adiponectin, and endotoxin concentrations were measured by ELISA. Food intake was measured using 3-day diet records. In addition, we assessed glucose and insulin levels as well as the homeostasis model assessment for insulin resistance (HOMA-IR. Results The most important finding from the present investigation was that the long-term interdisciplinary lifestyle therapy decreased dietary fat intake and endotoxin levels and improved HOMA-IR. We observed positive correlations between dietary fat intake and endotoxin levels, insulin levels, and the HOMA-IR. In addition, endotoxin levels showed positive correlations with IL-6 levels, insulin levels and the HOMA-IR. Interestingly, we observed a negative correlation between serum adiponectin and both dietary fat intake and endotoxin levels. Conclusions The present results indicate an association between dietary fat intake and endotoxin level, which was highly correlated with a decreased pro-inflammatory state and an improvement in HOMA-IR. In addition, this benefits effect may be associated with an increased adiponectin level, which suggests that the interdisciplinary therapy was effective in improving inflammatory pathways.

  20. Pantoea agglomerans: a marvelous bacterium of evil and good.Part I. Deleterious effects: Dust-borne endotoxins and allergens - focus on cotton dust.

    Science.gov (United States)

    Dutkiewicz, Jacek; Mackiewicz, Barbara; Lemieszek, Marta Kinga; Golec, Marcin; Milanowski, Janusz

    2015-01-01

    accumulation of platelets in pulmonary capillaries initiating an acute and chronic inflammation resulting in endothelial cell damage and extravasation of cells and fluids into the lung interstitium. These changes cause bronchoconstriction, the decrement of lung function expressed as reduction of forced expiratory volume in one second (FEV1) and/or diffusion capacity, increase in the airway hyperreactivity and subjective symptoms such as fever, airway irritation and chest tightness. The conclusions from these experiments, performed mostly 2-3 decades ago, did not loose their actuality until recently as so far no other cotton dust component was identified as a more important work-related hazard than bacterial endotoxin. Though also other microbial and plant constituents are considered as potential causative agents of byssinosis, the endotoxin produced by Pantoea agglomerans and other Gram-negative bacteria present in cotton dust is still regarded as a major cause of this mysterious disease.

  1. Pantoea agglomerans: a marvelous bacterium of evil and good.Part I. Deleterious effects: Dust-borne endotoxins and allergens – focus on cotton dust

    Directory of Open Access Journals (Sweden)

    Jacek Dutkiewicz

    2015-12-01

    that cause accumulation of platelets in pulmonary capillaries initiating an acute and chronic inflammation resulting in endothelial cell damage and extravasation of cells and fluids into the lung interstitium. These changes cause bronchoconstriction, the decrement of lung function expressed as reduction of forced expiratory volume in one second (FEV1 and/or diffusion capacity, increase in the airway hyperreactivity and subjective symptoms such as fever, airway irritation and chest tightness. The conclusions from these experiments, performed mostly 2-3 decades ago, did not loose their actuality until recently as so far no other cotton dust component was identified as a more important work-related hazard than bacterial endotoxin. Though also other microbial and plant constituents are considered as potential causative agents of byssinosis, the endotoxin produced by Pantoea agglomerans and other Gram-negative bacteria present in cotton dust is still regarded as a major cause of this mysterious disease.

  2. Pantoea agglomerans : a marvelous bacterium of evil and good. Part I. Deleterious effects: Dust-borne endotoxins and allergens – focus on cotton dust

    Directory of Open Access Journals (Sweden)

    Jacek Dutkiewicz

    2015-12-01

    that cause accumulation of platelets in pulmonary capillaries initiating an acute and chronic inflammation resulting in endothelial cell damage and extravasation of cells and fluids into the lung interstitium. These changes cause bronchoconstriction, the decrement of lung function expressed as reduction of forced expiratory volume in one second (FEV1 and/or diffusion capacity, increase in the airway hyperreactivity and subjective symptoms such as fever, airway irritation and chest tightness. The conclusions from these experiments, performed mostly 2-3 decades ago, did not loose their actuality until recently as so far no other cotton dust component was identified as a more important work-related hazard than bacterial endotoxin. Though also other microbial and plant constituents are considered as potential causative agents of byssinosis, the endotoxin produced by Pantoea agglomerans and other Gram-negative bacteria present in cotton dust is still regarded as a major cause of this mysterious disease.

  3. Point-Counterpoint: A Nucleic Acid Amplification Test for Streptococcus pyogenes Should Replace Antigen Detection and Culture for Detection of Bacterial Pharyngitis.

    Science.gov (United States)

    Pritt, Bobbi S; Patel, Robin; Kirn, Thomas J; Thomson, Richard B

    2016-10-01

    Nucleic acid amplification tests (NAATs) have frequently been the standard diagnostic approach when specific infectious agents are sought in a clinic specimen. They can be applied for specific agents such as S. pyogenes, or commercial multiplex NAATs for detection of a variety of pathogens in gastrointestinal, bloodstream, and respiratory infections may be used. NAATs are both rapid and sensitive. For many years, S. pyogenes testing algorithms used a rapid and specific group A streptococcal antigen test to screen throat specimens, followed, in some clinical settings, by a throat culture for S. pyogenes to increase the sensitivity of its detection. Now S. pyogenes NAATs are being used with increasing frequency. Given their accuracy, rapidity, and ease of use, should they replace antigen detection and culture for the detection of bacterial pharyngitis? Bobbi Pritt and Robin Patel of the Mayo Clinic, where S. pyogenes NAATs have been used for well over a decade with great success, will explain the advantages of this approach, while Richard (Tom) Thomson and Tom Kirn of the NorthShore University HealthSystem will discuss their concerns about this approach to diagnosing bacterial pharyngitis. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  4. Characteristics of Endotoxin-Altering Fractions Derived from Normal Serum III. Isolation and Properties of Horse Serum alpha(2)-Macroglobulin.

    Science.gov (United States)

    Yoshioka, M; Konno, S

    1970-05-01

    The endotoxin-altering activity of fractions isolated from normal horse serum was examined by incubation of Salmonella typhosa strain 0-901 endotoxin (Boivin) in a solution of the fraction, and subsequent quantitation of any diminution in the capacity of endotoxin to be precipitated by specific anti-endotoxin antiserum. The horse serum fraction isolated by precipitation with ammonium sulfate at a concentration between 1.6 and 2.7 m was incubated with Pronase PA and then with trypsin. When this partly digested fraction was passed twice through a Sephadex G-200 column and eluted with 0.2 m tris(hydroxymethyl)aminomethane buffer, most of the endotoxinaltering activity was found in the first protein peak designated F-1a. F-1a was found to be homogeneous and corresponded to an alpha(2)-macroglobulin by the techniques of electrophoresis, immunodiffusion, and ultracentrifugation. Approximately 100-fold more F-1a than endotoxin was needed to reduce the antigenicity of the endotoxin by one-half. Alteration was increased when F-1a was incubated with the endotoxin at acid pH or at 45 C rather than at 37 C and was lost after heating F-1a at 56 C for 30 min. N-ethylmaleimide increased the endotoxin-altering activity of horse serum, F-1a, and human plasma fraction III(0), whereas p-chloromercuribenzoate did not. On the other hand, diazonium-1-H-tetrazole, iodoacetic acid, and benzylchloride suppressed the activity of F-1a. When the interaction of endotoxin and F-1a was examined by immunodiffusion techniques, depolymerization of the endotoxin molecule was indicated. The endotoxin-altering factor of horse serum is discussed in relation to the mechanisms of other known reagents, such as deoxycholate and sodium lauryl sulfate.

  5. Characteristics of Endotoxin-Altering Fractions Derived from Normal Serum III. Isolation and Properties of Horse Serum α2-Macroglobulin

    Science.gov (United States)

    Yoshioka, Morimasa; Konno, Seishi

    1970-01-01

    The endotoxin-altering activity of fractions isolated from normal horse serum was examined by incubation of Salmonella typhosa strain 0-901 endotoxin (Boivin) in a solution of the fraction, and subsequent quantitation of any diminution in the capacity of endotoxin to be precipitated by specific anti-endotoxin antiserum. The horse serum fraction isolated by precipitation with ammonium sulfate at a concentration between 1.6 and 2.7 m was incubated with Pronase PA and then with trypsin. When this partly digested fraction was passed twice through a Sephadex G-200 column and eluted with 0.2 m tris(hydroxymethyl)aminomethane buffer, most of the endotoxinaltering activity was found in the first protein peak designated F-1a. F-1a was found to be homogeneous and corresponded to an α2-macroglobulin by the techniques of electrophoresis, immunodiffusion, and ultracentrifugation. Approximately 100-fold more F-1a than endotoxin was needed to reduce the antigenicity of the endotoxin by one-half. Alteration was increased when F-1a was incubated with the endotoxin at acid pH or at 45 C rather than at 37 C and was lost after heating F-1a at 56 C for 30 min. N-ethylmaleimide increased the endotoxin-altering activity of horse serum, F-1a, and human plasma fraction III0, whereas p-chloromercuribenzoate did not. On the other hand, diazonium-1-H-tetrazole, iodoacetic acid, and benzylchloride suppressed the activity of F-1a. When the interaction of endotoxin and F-1a was examined by immunodiffusion techniques, depolymerization of the endotoxin molecule was indicated. The endotoxin-altering factor of horse serum is discussed in relation to the mechanisms of other known reagents, such as deoxycholate and sodium lauryl sulfate. Images PMID:16557754

  6. Measurement of airborne bacteria and endotoxin generated during dental cleaning.

    Science.gov (United States)

    Dutil, Steve; Meriaux, Anne; de Latremoille, Marie-Chantale; Lazure, Louis; Barbeau, Jean; Duchaine, Caroline

    2009-02-01

    Dynamic dental instruments generate abundant aerosols in the work environment. Dental unit waterlines (DUWL) support a large microbial population and can be a significant source of bioaerosols generated during dental treatments. This study was conducted to characterize bioaerosol generation during dental treatments performed in standardized conditions. Culture-based method (R2A, and blood agar with and without O2) and fluorescence microscopy were used. Dental cleaning procedures were performed in an isolated treatment room with controlled ventilation rate. Andersen microbial samplers were used to collect culturable bioaerosols generated before (baseline), during, and after 2 hr of dental treatments. Inhalable dust samplers were used to measure total bioaerosols content in dental hygienist's and patients' breathing zones. AGI-30 were used for the collection of the endotoxin. The use of fluorescence microscopy in combination with culture demonstrated that dental staff and patients were exposed to up to 1.86 E+05 bacteria/m(3) generated during treatments. Fortunately, bioaerosols returned to baseline within 2 hr after the dental procedures. The small diameter of the aerosols generated (< 1 microm) suggests that the risk of contact between the aerosolized bacteria and the respiratory system of exposed individuals is likely to occur.

  7. Bacterial Proteasomes.

    Science.gov (United States)

    Jastrab, Jordan B; Darwin, K Heran

    2015-01-01

    Interest in bacterial proteasomes was sparked by the discovery that proteasomal degradation is required for the pathogenesis of Mycobacterium tuberculosis, one of the world's deadliest pathogens. Although bacterial proteasomes are structurally similar to their eukaryotic and archaeal homologs, there are key differences in their mechanisms of assembly, activation, and substrate targeting for degradation. In this article, we compare and contrast bacterial proteasomes with their archaeal and eukaryotic counterparts, and we discuss recent advances in our understanding of how bacterial proteasomes function to influence microbial physiology.

  8. Diagnosis of bacterial infection

    African Journals Online (AJOL)

    rapid and easy-to-use test for bacterial infections. Clearly, this is a very ... detect antigens or specific antibodies, e.g. group A streptococcal antigen testing can be employed to reduce antibiotic use. Culture-based tests are often ... White blood cell count 12 000 cells/mm³; or the presence of >10% ...

  9. Chlorogenic acid ameliorates endotoxin-induced liver injury by promoting mitochondrial oxidative phosphorylation

    International Nuclear Information System (INIS)

    Zhou, Yan; Ruan, Zheng; Zhou, Lili; Shu, Xugang; Sun, Xiaohong; Mi, Shumei; Yang, Yuhui; Yin, Yulong

    2016-01-01

    Acute or chronic hepatic injury is a common pathology worldwide. Mitochondrial dysfunction and the depletion of adenosine triphosphate (ATP) play important roles in liver injury. Chlorogenic acids (CGA) are some of the most abundant phenolic acids in human diet. This study was designed to test the hypothesis that CGA may protect against chronic lipopolysaccharide (LPS)-induced liver injury by modulating mitochondrial energy generation. CGA decreased the activities of serum alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase. The contents of ATP and adenosine monophosphate (AMP), as well as the ratio of AMP/ATP, were increased after CGA supplementation. The activities of enzymes that are involved in glycolysis were reduced, while those of enzymes involved in oxidative phosphorylation were increased. Moreover, phosphorylated AMP-activated protein kinase (AMPK), and mRNA levels of AMPK-α, peroxisome proliferator-activated receptor-gamma coactivator 1α (PGC-1α), nuclear respiratory factor 1, and mitochondrial DNA transcription factor A were increased after CGA supplementation. Collectively, these findings suggest that the hepatoprotective effect of CGA might be associated with enhanced ATP production, the stimulation of mitochondrial oxidative phosphorylation and the inhibition of glycolysis. - Highlights: • Dietary supplementation with chlorogenic acid (CGA) improved endotoxin-induced liver injury. • Chlorogenic acid enhances ATP increase and shifts energy metabolism, which is correlated with up-regulation AMPK and PGC-1α. • The possible mechanism of CGA on mitochondrial biogenesis was correlated with up-regulation AMPK and PGC-1α.

  10. Niacinamide abrogates the organ dysfunction and acute lung injury caused by endotoxin.

    Science.gov (United States)

    Kao, Shang-Jyh; Liu, Demeral David; Su, Chain-Fa; Chen, Hsing I

    2007-09-01

    Poly (ADP-ribose) synthabse (PARS) or polymerase (PARP) is a cytotoxic enzyme causing cellular damage. Niacinamide inhibits PARS or PARP. The present experiment tests the effects of niacinamide (NCA) on organ dysfunction and acute lung injury (ALI) following lipopolysaccharide (LPS). LPS was administered to anesthetized rats and to isolated rat lungs. In anesthetized rats, LPS caused systemic hypotension and increased biochemical factors, nitrate/nitrite (NOx), methyl guanidine (MG), tumor necrosis factoralpha (TNFalpha), and interleukin-1beta (IL-1beta). In isolated lungs, LPS increased lung weight (LW) to body weight ratio, LW gain, protein and dye tracer leakage, and capillary permeability. The insult also increased NOx, MG, TNFalpha, and IL-1beta in lung perfusate, while decreased adenosine triphosphate (ATP) content with an increase in PARP activity in lung tissue. Pathological examination revealed pulmonary edema with inflammatory cell infiltration. These changes were abrogated by posttreatment (30 min after LPS) with NCA. Following LPS, the inducible NO synthase (iNOS) mRNA expression was increased. NCA reduced the iNOS expression. Niacinamide exerts protective effects on the organ dysfunction and ALI caused by endotoxin. The mechanisms may be mediated through the inhibition on the PARP activity, iNOS expression and the subsequent suppression of NO, free radicals, and proinflammatory cytokines with restoration of ATP.

  11. Capture of lipopolysaccharide (endotoxin by the blood clot: a comparative study.

    Directory of Open Access Journals (Sweden)

    Margaret T Armstrong

    Full Text Available In vertebrates and arthropods, blood clotting involves the establishment of a plug of aggregated thrombocytes (the cellular clot and an extracellular fibrillar clot formed by the polymerization of the structural protein of the clot, which is fibrin in mammals, plasma lipoprotein in crustaceans, and coagulin in the horseshoe crab, Limulus polyphemus. Both elements of the clot function to staunch bleeding. Additionally, the extracellular clot functions as an agent of the innate immune system by providing a passive anti-microbial barrier and microbial entrapment device, which functions directly at the site of wounds to the integument. Here we show that, in addition to these passive functions in immunity, the plasma lipoprotein clot of lobster, the coagulin clot of Limulus, and both the platelet thrombus and the fibrin clot of mammals (human, mouse operate to capture lipopolysaccharide (LPS, endotoxin. The lipid A core of LPS is the principal agent of gram-negative septicemia, which is responsible for more than 100,000 human deaths annually in the United States and is similarly toxic to arthropods. Quantification using the Limulus Amebocyte Lysate (LAL test shows that clots capture significant quantities of LPS and fluorescent-labeled LPS can be seen by microscopy to decorate the clot fibrils. Thrombi generated in the living mouse accumulate LPS in vivo. It is suggested that capture of LPS released from gram-negative bacteria entrapped by the blood clot operates to protect against the disease that might be caused by its systemic dispersal.

  12. Chlorogenic acid ameliorates endotoxin-induced liver injury by promoting mitochondrial oxidative phosphorylation

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Yan [State Key Laboratory of Food Science and Technology and School of Food Science, Nanchang University, Nanchang 330047 (China); College of Food Safety, Guizhou Medical University, Guiyang 550025 (China); Ruan, Zheng, E-mail: ruanzheng@ncu.edu.cn [State Key Laboratory of Food Science and Technology and School of Food Science, Nanchang University, Nanchang 330047 (China); Zhou, Lili; Shu, Xugang [State Key Laboratory of Food Science and Technology and School of Food Science, Nanchang University, Nanchang 330047 (China); Sun, Xiaohong [College of Food Safety, Guizhou Medical University, Guiyang 550025 (China); Mi, Shumei; Yang, Yuhui [State Key Laboratory of Food Science and Technology and School of Food Science, Nanchang University, Nanchang 330047 (China); Yin, Yulong, E-mail: yinyulong@isa.ac.cn [State Key Laboratory of Food Science and Technology and School of Food Science, Nanchang University, Nanchang 330047 (China); Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125 (China)

    2016-01-22

    Acute or chronic hepatic injury is a common pathology worldwide. Mitochondrial dysfunction and the depletion of adenosine triphosphate (ATP) play important roles in liver injury. Chlorogenic acids (CGA) are some of the most abundant phenolic acids in human diet. This study was designed to test the hypothesis that CGA may protect against chronic lipopolysaccharide (LPS)-induced liver injury by modulating mitochondrial energy generation. CGA decreased the activities of serum alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase. The contents of ATP and adenosine monophosphate (AMP), as well as the ratio of AMP/ATP, were increased after CGA supplementation. The activities of enzymes that are involved in glycolysis were reduced, while those of enzymes involved in oxidative phosphorylation were increased. Moreover, phosphorylated AMP-activated protein kinase (AMPK), and mRNA levels of AMPK-α, peroxisome proliferator-activated receptor-gamma coactivator 1α (PGC-1α), nuclear respiratory factor 1, and mitochondrial DNA transcription factor A were increased after CGA supplementation. Collectively, these findings suggest that the hepatoprotective effect of CGA might be associated with enhanced ATP production, the stimulation of mitochondrial oxidative phosphorylation and the inhibition of glycolysis. - Highlights: • Dietary supplementation with chlorogenic acid (CGA) improved endotoxin-induced liver injury. • Chlorogenic acid enhances ATP increase and shifts energy metabolism, which is correlated with up-regulation AMPK and PGC-1α. • The possible mechanism of CGA on mitochondrial biogenesis was correlated with up-regulation AMPK and PGC-1α.

  13. Plasma endotoxin activity in Eastern grey kangaroos (Macropus giganteus) with lumpy jaw disease.

    Science.gov (United States)

    Sotohira, Yukari; Suzuki, Kazuyuki; Otsuka, Marina; Tsuchiya, Masakazu; Shimamori, Toshio; Nishi, Yasunobu; Tsukano, Kenji; Asakawa, Mitsuhiko

    2017-06-29

    Progressive pyogranulomatous osteomyelitis involving the mandible or maxilla of captive macropods, referred to as "Lumpy jaw disease (LJD)", is one of the most significant causes of illness and death in captive macropods. The aim of the present study was to evaluate the relationship between the severity of LJD and plasma endotoxin activity in kangaroos. Plasma samples obtained from moderate (n=24) and severe LJD (n=12), and healthy kangaroos (n=46), were diluted 1:20 in endotoxin-free water and heated to 80°C for 10 min. Plasma endotoxin activity was measured using the Limulus amebocyte lysate (LAL)-kinetic turbidimetric (KT) assay. Plasma endotoxin activity was higher in kangaroos with severe LJD (0.199 ± 0.157 EU/ml) than in those with moderate LJD (0.051 ± 0.012 EU/ml, P<0.001) and healthy controls (0.057 ± 0.028 EU/ml, P<0.001). Our results suggest that the severity of LJD in captive macropods may be related to the plasma endotoxin activity.

  14. The efficient removal of endotoxins from insulin using quaternized polyethyleneimine-coated porous zirconia.

    Science.gov (United States)

    McNeff, C; Zhao, Q; Almlöf, E; Flickinger, M; Carr, P W

    1999-10-15

    The synthesis and use of a zirconia-based, alkali-stable strong anion-exchange stationary phase are described for the removal of pyrogenic lipopolysaccharides (LPS) from insulin. The strong anion-exchange material is produced by deposition of polyethyleneimine (PEI) onto porous zirconia particles, followed by cross-linking with a novel reagent, 1,2-bis-(2-iodoethoxy) ethane, and quaternization with iodomethane. Physical characterization of the chromatographic support shows that it has an ion-exchange capacity of 0.6 mmol/g, and 82% of the amine sites on the surface are in quaternized form. Isocratic elution of small benzoic acid derivatives shows good column efficiency. The two primary virtues of this material are its chemical stability under alkali conditions (up to pH 13) and its lower hydrophobicity compared to previously described alkali-stable PEI-coated zirconia supports cross-linked with 1,10-diiododecane. Using this new zirconia-based phase, a purification protocol is developed for the efficient removal of Escherichia coli 0111:B4 LPS from bovine insulin samples. An endotoxin clearance rate of up to 1.3 x 10(8) was attained. Endotoxin levels were reduced to less than 5 endotoxin units/ml even at initial contamination levels as high as 5.0 x 10(6) endotoxin units/ml. Furthermore, endotoxin adsorbed to the porous zirconia column may be easily removed (depyrogenated) using alkali for repeated purification cycles. Copyright 1999 Academic Press.

  15. Fingolimod against endotoxin-induced fetal brain injury in a rat model.

    Science.gov (United States)

    Yavuz, And; Sezik, Mekin; Ozmen, Ozlem; Asci, Halil

    2017-11-01

    Fingolimod is a sphingosine-1-phosphate receptor modulator used for multiple sclerosis treatment and acts on cellular processes such as apoptosis, endothelial permeability, and inflammation. We hypothesized that fingolimod has a positive effect on alleviating preterm fetal brain injury. Sixteen pregnant rats were divided into four groups of four rats each. On gestational day 17, i.p. endotoxin was injected to induce fetal brain injury, followed by i.p. fingolimod (4 mg/kg maternal weight). Hysterotomy for preterm delivery was performed 6 h after fingolimod. The study groups included (i) vehicle controls (i.p. normal saline only); (ii) positive controls (endotoxin plus saline); (iii) saline plus fingolimod; and (iv) endotoxin plus fingolimod treatment. Brain tissues of the pups were dissected for evaluation of interleukin (IL)-6, caspase-3, and S100β on immunohistochemistry. Maternal fingolimod treatment attenuated endotoxin-related fetal brain injury and led to lower immunoreactions for IL-6, caspase-3, and S100β compared with endotoxin controls (P < 0.0001 for all comparisons). Antenatal maternal fingolimod therapy had fetal neuroprotective effects by alleviating preterm birth-related fetal brain injury with inhibitory effects on inflammation and apoptosis. © 2017 Japan Society of Obstetrics and Gynecology.

  16. Genotoxicity assessment of pulp and paper mill effluent before and after bacterial degradation using Allium cepa test.

    Science.gov (United States)

    Haq, Izharul; Kumar, Sharad; Raj, Abhay; Lohani, Mohtashim; Satyanarayana, G N V

    2017-02-01

    A lignin peroxidases-producing Serratia liquefaciens was used for bioremediation of pulp and paper (P&P) mill effluent. The treatment led to reduction of chemical oxygen demand (COD), colour, lignin and phenolic content by 84%, 72%, 61% and 95%, respectively. The effluent detoxification was studied by genotoxicity assays using Allium cepa L. (onion) root tip cells. Genotoxicity studies included measuring mitotic index (MI), chromosomal aberrations (CA) and nuclear abnormalities (NA) in root tip cells following treatment with 25, 50, 75 and 100% (v/v) of effluent. The root tip cells grown in untreated effluent showed a significant decrease in MI from 69% (control) to 32%, 27%, 22% and 11% at 25%, 50%, 75% and 100% effluent concentration, respectively. This indicated that the untreated effluent was highly cytotoxic in nature. Further, root tip cells, when treated with different concentrations of effluent showed various CA and NA including c-mitosis, stickiness, chromosome loss, chromosome break, anaphase bridge, multipolar anaphase, vagrant chromosomes, micronucleated and binucleated cells. The MI observed in root tip cells grown in bacterial treated effluents at similar concentrations (25, 50, 75 and 100% v/v) showed an increase of 33%, 36%, 42% and 66%. CA showed a substantial decrease and in some instances, complete absence of CA was also observed. The findings suggest that S. liquefaciens culture could be a potential bacterial culture for bioremediation of P&P mill effluent, as it is effective in substantial lowering of pollutants load as well as reduces the cytotoxic and genotoxic effects of effluent. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Evaluation of a bacterial bioluminescence bioassay as a predictive surrogate for mysid chronic estimator tests with produced water

    Energy Technology Data Exchange (ETDEWEB)

    Korenaga, G.L.; Stine, E.R.; Henry, L.R. [and others

    1995-12-01

    Toxicity limits are appearing more frequently in permits for produced water discharges. A bioluminescent bacteria bioassay has been proposed as a screening tool to predict toxicity in higher organisms, which are more expensive and require longer testing times. Before such a surrogate screen can be used, a correlation must be demonstrated between toxicity in the surrogate and the species of interest. This paper describes tests comparing produced water toxicity in the bioluminescent bacteria test and in the myoid shrimp chronic estimator test, which is frequently required in Gulf of Mexico discharge Under these test conditions, the bacteria test was not adequately predictive of produced water chronic toxicity to the myoid shrimp.

  18. Functional13C-urea and glucose hydrogen/methane breath tests reveal significant association of small intestinal bacterial overgrowth in individuals with active Helicobacter pylori infection.

    Science.gov (United States)

    Enko, Dietmar; Kriegshäuser, Gernot

    2017-01-01

    Helicobacter pylori infection is considered to alter the bacterial flora in the upper gastrointestinal tract. This study aimed at investigating the presence of small intestinal bacterial overgrowth (SIBO) in patients with active H. pylori infection assessed by functional breath testing. A total of 109 outpatients, who were referred for the H. pylori 13 C-urea breath test ( 13 C-UBT) by general practitioners and specialists, were also tested for the presence of SIBO by the glucose hydrogen (H 2 )/methane (CH 4 ) breath test (HMBT). A detailed anamnesis was carried out about the history of H. pylori infection, eradication therapies, proton pump inhibitor intake, and comorbidities. In total, 36/109 (33.0%) patients had a positive H. pylori 13 C-UBT, and 35/109 (32.1%) patients had a positive glucose HMBT, the latter being indicative of SIBO. Interestingly, individuals with a positive H. pylori 13 C-UBT were significantly more often associated with a positive glucose HMBT (p=0.002). Cohen's κ measuring agreement between the 13 C-UBT and the glucose HMBT was 0.31 (confidence intervals: 0.12-0.50) (p=0.001). Altogether, 19 of 54 (35.2%) patients, who had completed up to four eradication therapies, were diagnosed with SIBO by HMBT. H. pylori infection was found to be significantly associated with the presence of SIBO as determined by functional breath testing. In addition, SIBO rates appeared to have increased after completed eradication therapies. However, further longitudinal studies are warranted to fully elucidate the relationship and treatment modalities of coincident H. pylori infection and SIBO. Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  19. Clinical value of radionuclide small intestine transit time measurement combined with lactulose hydrogen breath test for the diagnosis of bacterial overgrowth in irritable bowel syndrome.

    Science.gov (United States)

    Ning, Yanli; Lou, Cen; Huang, Zhongke; Chen, Dongfang; Huang, Huacheng; Chen, Liang; Zhang, Bucheng; Dai, Ning; Zhao, Jianmin; Zhen, Xia

    2016-01-01

    Small intestine bacterial overgrowth (SIBO) may be a pathogenetic factor for irritable bowel syndrome (IBS). This syndrome cannot be explained by structural abnormalities and has no specific diagnostic laboratory tests or biomarkers. We studied quantitatively and semi-quantitatively, using lactulose hydrogen breath test (LHBT), small intestinal transit time (SITT) (99m)technetium-diethylene triamine pentaacetic acid ((99m)Tc-DTPA) in order to examine the mobility of small intestine as an indication of bacterial overgrowth in patients. Eighty nine consecutive patients who met Rome criteria for IBS were retrospectively studied. According to the diagnostic criteria, all patients were divided into two groups: the SIBO group and the non-SIBO group. The tracer was a mixture of 10g lactulose, 37MBq (99m)Tc-DTPA and 100mL water. The patient drank the whole mixture during 1min and the SITT study started immediately. The SITT and the LHBT followed every 15min for up to 3h after emptying the urine bladder. Spearman's rank correlation was applied to assess the correlation of oro-cecum transit time (OCTT) between imaging and LHBT. The semi-quantitative index between the SIBO group and the non-SIBO group was analyzed with Wilcoxon's rank sum test. If there was significant group difference, the receiver operating characteristic (ROC) curve was used. Pintestinal transit time study using a lactose hydrogen breath test and (99m)Tc-DTPA is a real-time test for small intestine bacteria overgrowth in IBS patients and can be used as an indicator of the disease.

  20. Cytokine release from human peripheral blood leucocytes incubated with endotoxin with and without prior infection with influenza virus

    DEFF Research Database (Denmark)

    Banner, Jytte; Smith, H; Sweet, C

    1993-01-01

    , IL-6 and tumour necrosis factor (TNF)-alpha were examined, using ELISA assays, in culture supernatants of human peripheral blood leucocytes infected with influenza virus and subsequently incubated with endotoxin. Levels of TNF-alpha were increased compared to cells incubated with virus or endotoxin...

  1. Optimization of airborne endotoxin exposure assessment: Effects of filter type, transport conditions, extraction solutions, and storage of samples and extracts

    NARCIS (Netherlands)

    Spaan, S.; Heederik, D.J.J.; Thorne, P.S.; Wouters, I.M.

    2007-01-01

    Endotoxin exposure occurs in homes and occupational environments and is known to cause adverse health effects. In order to compare results from different studies and establish standards, airborne endotoxin exposures should be assessed using standardized methods. Although the European Committee for

  2. A biological study establishing the endotoxin limit for in vitro proliferation of human mesenchymal stem cells

    Directory of Open Access Journals (Sweden)

    Yusuke Nomura

    2017-12-01

    Conclusions: Since endotoxins can affect various cellular functions, an endotoxin limit should be set for in vitro MSC cultures. The lowest observed adverse effect level was determined to be 0.1 ng/ml based on the effect on MSC proliferation.

  3. Targeting naproxen coupled to human serum albumin to nonparenchymal cells reduces endotoxin-induced mortality in rats with biliary cirrhosis

    NARCIS (Netherlands)

    Albrecht, C.; Meijer, D.K F; Lebbe, C; Sägesser, H; Melgert, B.N; Poelstra, Klaas; Reichen, J

    1997-01-01

    Endotoxin is thought to play a major role in cirrhotic liver disease, Cyclo-oxygenase inhibitors were shown to be partially protective against endotoxin but cannot be used in cirrhotic patients because of renal side-effects, We argued that administration of naproxen (NAP) linked to human serum

  4. Influence of endotoxin-induced sepsis on the requirements of propofol-fentanyl infusion rate in pigs

    DEFF Research Database (Denmark)

    Bollen, Peter; Nielsen, Bjørn J; Toft, Palle

    2007-01-01

    Endotoxin-induced sepsis in pigs is a recognized experimental model for the study of human septic shock. Generally, pigs are brought into general anaesthesia before sepsis is induced. It is our experience that drug dosages of propofol and fentanyl need to be reduced during endotoxin-induced sepsi...

  5. A NEW ANIMAL-MODEL FOR HUMAN PREECLAMPSIA - ULTRA-LOW-DOSE ENDOTOXIN INFUSION IN PREGNANT RATS

    NARCIS (Netherlands)

    FAAS, MM; SCHUILING, GA; BALLER, JFW; VISSCHER, CA; BAKKER, WW

    OBJECTIVE: An animal model for preeclampsia was developed by means of an ultra-low-dose endotoxin infusion protocol in conscious pregnant rats. STUDY DESIGN: Rats received a permanent jugular vein cannula on day 0 of pregnancy, through which endotoxin (1.0 mu/kg body weight) (n = 10) or saline

  6. Bacterial adhesion

    NARCIS (Netherlands)

    Loosdrecht, van M.C.M.

    1988-01-01

    As mentioned in the introduction of this thesis bacterial adhesion has been studied from a variety of (mostly practice oriented) starting points. This has resulted in a range of widely divergent approaches. In order to elucidate general principles in bacterial adhesion phenomena, we felt it

  7. Common studied polymorphisms do not affect plasma cytokine levels upon endotoxin exposure in humans

    DEFF Research Database (Denmark)

    Taudorf, Sarah; Krabbe, K.S.; Berg, R.M.

    2008-01-01

    The aim of this study was to investigate to what extent single nucleotide polymorphisms (SNPs) in promoter regions of genes of Toll-like receptor (TLR)-4, tumour necrosis factor (TNF)-alpha, interleukin (IL)-18, interferon (IFN)-gamma, IL-6 and IL-10 affect the cytokine response during a controlled......-607, IFN-gamma+874, IL-6-174, IL-10-592 and IL-10-1082) and endotoxin-induced changes in plasma levels of TNF-alpha, IL-6 and IL-10. IL-18 levels were unaffected by endotoxin. In conclusion, the investigated SNPs did not affect endotoxin-induced low-grade cytokine production of TNF-alpha, IL-6, IL-18 or IL......-10 in healthy young men. Previous reports of a major heritability factor in the inflammatory response may be due to other target genes or effects in older age groups or women Udgivelsesdato: 2008/4...

  8. Sensitisation to common allergens and respiratory symptoms in endotoxin exposed workers

    DEFF Research Database (Denmark)

    Basinas, Ioannis; Schlünssen, Vivi; Heederik, Dick

    2012-01-01

    E-mediated sensitisation to common allergens and self-reported health symptoms were assessed using logistic regression and generalised additive modelling. Adjustments were made for study, age, sex, atopic predisposition, smoking habit and farm childhood. Heterogeneity was assessed by analysis stratified by study. Results......, and levels above 100 EU/m3 significantly increased the risk of chronic bronchitis (peffect modification except for allergic sensitisation. Only among workers without a farm childhood, endotoxin exposure was inversely associated with allergic sensitisation....... Heterogeneity was primarily present for biofuel workers. Conclusions Occupational endotoxin exposure has a protective effect on allergic sensitisation and hay fever but increases the risk for organic dust toxic syndrome and chronic bronchitis. Endotoxin's protective effects are most clearly observed among...

  9. Panum's studies on "putrid poison" 1856. An early description of endotoxin

    DEFF Research Database (Denmark)

    Kolmos, Hans Jørn

    2006-01-01

    In 1855-1856 the Danish physiologist, Peter Ludvig Panum (1820-1885) performed a series of remarkable experiments on "putrid poison", a hypothetical substance claimed to be responsible for the symptoms and signs seen in patients with sepsis. Dogs were given intravenous infusions of putrefying......, but insoluble in alcohol, and with preserved activity after long-term boiling. "Putrid poison" has striking similarities with endotoxin, a cell wall product of Gram-negative bacteria and a powerful inducer of inflammation and septic shock. Thanks to Panum's carefully arranged experiments and meticulous...... recording of observations it is fair to conclude that "putrid poison" was endotoxin, and as such he deserves credit for being the first to have described endotoxin. Panum published his observations twice, in Danish in 1856, and in German in 1874. At first he rejected the possibility that bacteria could play...

  10. Seasonal variation in airborne endotoxin levels in indoor environments with different micro-environmental factors in Seoul, South Korea.

    Science.gov (United States)

    Hwang, Sung Ho; Park, Dong Jin; Park, Wha Me; Park, Dong Uk; Ahn, Jae Kyoung; Yoon, Chung Sik

    2016-02-01

    This study evaluated the variation over a year in airborne endotoxin levels in the indoor environment of five university laboratories in Seoul, South Korea, and examined the micro-environmental factors that influenced endotoxin levels. These included temperature, relative humidity, CO2, CO, illumination, and wind velocity. A total of 174 air samples were collected and analyzed using the kinetic limulus amebocyte lysate assay. Endotoxin levels ranged from analysis showed that the environmental factors affecting endotoxin levels were temperature (coefficient=-0.388, p<0.001) and illumination (coefficient=-0.370, p<0.001). Strategies aimed at reducing airborne endotoxin levels in the indoor environments may be most effective if they focus on illumination. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Quantification of bacterial species of the vaginal microbiome in different groups of women, using nucleic acid amplification tests

    Directory of Open Access Journals (Sweden)

    Jespers Vicky

    2012-05-01

    Full Text Available Abstract Background The vaginal microbiome plays an important role in urogenital health. Quantitative real time Polymerase Chain Reaction (qPCR assays for the most prevalent vaginal Lactobacillus species and bacterial vaginosis species G. vaginalis and A. vaginae exist, but qPCR information regarding variation over time is still very limited. We set up qPCR assays for a selection of seven species and defined the temporal variation over three menstrual cycles in a healthy Caucasian population with a normal Nugent score. We also explored differences in qPCR data between these healthy women and an ‘at risk’ clinic population of Caucasian, African and Asian women with and without bacterial vaginosis (BV, as defined by the Nugent score. Results Temporal stability of the Lactobacillus species counts was high with L. crispatus counts of 108 copies/mL and L. vaginalis counts of 106 copies/mL. We identified 2 types of ‘normal flora’ and one ‘BV type flora’ with latent class analysis on the combined data of all women. The first group was particularly common in women with a normal Nugent score and was characterized by a high frequency of L. crispatus, L. iners, L. jensenii, and L. vaginalis and a correspondingly low frequency of L. gasseri and A. vaginae. The second group was characterized by the predominance of L. gasseri and L. vaginalis and was found most commonly in healthy Caucasian women. The third group was commonest in women with a high Nugent score but was also seen in a subset of African and Asian women with a low Nugent score and was characterized by the absence of Lactobacillus species (except for L. iners but the presence of G. vaginalis and A. vaginae. Conclusions We have shown that the quantification of specific bacteria by qPCR contributes to a better description of the non-BV vaginal microbiome, but we also demonstrated that differences in populations such as risk and ethnicity also have to be taken into account. We believe

  12. Airborne endotoxin concentrations in various work areas within two cotton textile mills in the People's Republic of China.

    Science.gov (United States)

    Olenchock, S A; Christiani, D C; Mull, J C; Ye, T T; Lu, P L

    1990-12-01

    As part of a multidisciplinary longitudinal approach to assess the roles of airborne cotton dust and endotoxins in affecting the respiratory health of cotton textile workers, this study was designed to quantify the endotoxin contamination of airborne vertically elutriated and total dusts. Yarn preparation areas (opening through fine spinning) were studied at two cotton textile mills which had been studied 5 years previously in Shanghai. People's Republic of China, Filter, with vertically elutriated (VE) or total dusts were mailed to the United States and endotoxin analyses were performed for each filter in duplicate with the quantitative chromogenic modification of the Limulus amebocyte lysate assay. Dusts from all areas of the textile mills contained endotoxins. Endotoxin burdens in VE dusts from the carding area were similar in both milk while the endotoxin contamination of total dust from carding in Mill 1 was over threefold greater than that of total dust from carding in Mill 2. All other areas differed between milk in both VE and total dust endotoxin burdens. Mean endotoxin levels in VE dusts from all areas of both mills were well above the reported threshold of 90 EU/m3 for acute pulmonary function effects in humans. Comparison of selected areas of both mills from the present study with the same work areas from the previous study showed that, in general, the airborne endotoxin burden was higher than levels found 5 years ago in these two mills. The data suggest that even with reduced or unchanged gravimetric dust levels in these two cotton textile mills, airborne endotoxin levels were higher and provided an increased potential for adverse respiratory response in exposed workers.

  13. The lower genital tract microbiota in relation to cytokine-, SLPI- and endotoxin levels: application of checkerboard DNA-DNA hybridization (CDH).

    Science.gov (United States)

    Nikolaitchouk, Natalia; Andersch, Björn; Falsen, Enevold; Strömbeck, Louise; Mattsby-Baltzer, Inger

    2008-04-01

    In the present study the lower genital tract microbiota in asymptomatic fertile women (n=34) was identified and quantified by culturing vaginal secretions. Also, vaginal and cervical samples were analyzed by a semiquantitative checkerboard DNA-DNA hybridization technique (CDH) based on genomic probes prepared from 13 bacterial species (Bacteroides ureolyticus, Escherichia coli, Fusobacterium nucleatum, Gardnerella vaginalis, Mobiluncus curtisii ss curtisii, Prevotella bivia, Prevotella disiens, Prevotella melaninogenica, Atopobium vaginae, Lactobacillus iners, Staphylococcus aureus ss aureus, Streptococcus anginosus, and Streptococcus agalactiae). The bacterial species found by either culture or CDH were correlated with proinflammatory cytokines (IL-1 alpha, IL-1 beta, IL-6, IL-8), secretory leukocyte protease inhibitor (SLPI), and endotoxin in the cervicovaginal samples. Grading the women into healthy, intermediate, or bacterial vaginosis (BV) as based on Gram staining of vaginal smears, the viable counts of lactobacilli (L. gasseri) and of streptococci-staphylococci combined were highest in the intermediate group. In BV, particularly the high concentrations of Actinomyces urogenitalis, Atopobium vaginae, and Peptoniphilus harei were noted (>or=10(11) per ml). The total viable counts correlated with both cervical IL-1 alpha and IL-1 beta. A strong negative correlation was observed between L. iners and total viable counts, G. vaginalis, or cervical IL-1 alpha, while it correlated positively with SLPI. Analysis of vaginal and cervical samples from 26 out of the 34 women by CDH showed that anaerobic bacteria were more frequently detected by CDH compared to culture. By this method, A. vaginae correlated with G. vaginalis, and L. iners with S. aureus. With regard to cytokines, B. ureolyticus correlated with both cervical and vaginal IL-1 alpha as well as with cervical IL-8, while F. nucleatum, S. agalactiae, S. anginosus, or S. aureus correlated with vaginal IL-1 alpha

  14. Biomonitoring of the genotoxic potential of aqueous extracts of soils and bottom ash resulting from municipal solid waste incineration, using the comet and micronucleus tests on amphibian (Xenopus laevis) larvae and bacterial assays (Mutatox and Ames tests).

    Science.gov (United States)

    Mouchet, F; Gauthier, L; Mailhes, C; Jourdain, M J; Ferrier, V; Triffault, G; Devaux, A

    2006-02-15

    The management of contaminated soils and wastes is a matter of considerable human concern. The present study evaluates the genotoxic potential of aqueous extracts of two soils (leachates) and of bottom ash resulting from municipal solid waste incineration (MSWIBA percolate), using amphibian larvae (Xenopus laevis). Soil A was contaminated by residues of solvents and metals and Soil B by polycyclic aromatic hydrocarbons and metals. MSWIBA was predominantly contaminated by metals. Two genotoxic endpoints were analysed in circulating erythrocytes taken from larvae: clastogenic and/or aneugenic effects (micronucleus induction) after 12 days of exposure and DNA-strand-breaking potency (comet assay) after 1 and 12 days of exposure. In addition, in vitro bacterial assays (Mutatox and Ames tests) were carried out and the results were compared with those of the amphibian test. Physicochemical analyses were also taken into account. Results obtained with the amphibians established the genotoxicity of the aqueous extracts and the comet assay revealed that they were genotoxic from the first day of exposure. The latter test could thus be considered as a genotoxicity-screening tool. Although genotoxicity persisted after 12 days' exposure, DNA damage decreased overall between days 1 and 12 in the MSWIBA percolate, in contrast to the soil leachates. Bacterial tests detected genotoxicity only for the leachate of soil A (Mutatox). The results confirm the ecotoxicological relevance of the amphibian model and underscore the importance of bioassays, as a complement to physico-chemical data, for risk evaluation.

  15. A bacterial sensitivity test to determine the effectiveness of minocycline HCI (Minocin), erythromycin (Erythrocin) and ampicillin (Ampicin) on the predominant microorganisms present in a diseased periodontium.

    Science.gov (United States)

    Angeles, B L; Book, D R; Go, K G; Lim, D J; Uy, H G

    1994-01-01

    The purpose of this study was to determine the effectiveness of the three antimicrobials--Minocycline HCI, Erythromycin and Ampicillin based on the percentage reduction of bacteria present in subgingival microflora and in vitro assessment of antibiotic susceptibility of cultured strains of predominant microorganisms present in a diseased periodontium. Twelve volunteers 18 to 65 years of age, with moderate to severe periodontal disease, were randomly divided into Group A and Group B of 6 members each. Oral lavage procedure was performed to Group A and Group B received systemic administration of antibiotic for five days. Patients 1 & 2, 3 & 4 and 5 & 6 received minocycline HCI, Erythromycin and Ampicillin respectively. Microbiologic samples in the subgingival crevicular area in selected tooth exhibiting clinical periodontal breakdown were obtained from all the subjects prior to and after the oral lavage procedure and systemic drug administration. Streptococcus viridans is the most predominant aerobic microorganism obtained from 83% of samples. However no anaerobic microorganism has been isolated. Bacterial sensitivity testing showed 60% of samples with positive growth of microorganisms (S. viridans) were also equally sensitive to Minocycline HCI, Erythromycin and Ampicillin. Oral lavage proved to be ineffective in reducing the number of bacteria. However, systemic drug administration revealed that there was a reduction in bacterial count after taking such antibiotics for five days which is more favorable to Minocycline HCI.

  16. [Diagnosis of bacterial vaginosis].

    Science.gov (United States)

    Djukić, Slobodanka; Ćirković, Ivana; Arsić, Biljana; Garalejić, Eliana

    2013-01-01

    Bacterial vaginosis is a common, complex clinical syndrome characterized by alterations in the normal vaginal flora. When symptomatic, it is associated with a malodorous vaginal discharge and on occasion vaginal burning or itching. Under normal conditions, lactobacilli constitute 95% of the bacteria in the vagina. Bacterial vaginosis is associated with severe reduction or absence of the normal H2O2-producing lactobacilli and overgrowth of anaerobic bacteria and Gardnerella vaginalis, Atopobium vaginae, Mycoplasma hominis and Mobiluncus species. Most types of infectious disease are diagnosed by culture, by isolating an antigen or RNA/DNA from the microbe, or by serodiagnosis to determine the presence of antibodies to the microbe. Therefore, demonstration of the presence of an infectious agent is often a necessary criterion for the diagnosis of the disease. This is not the case for bacterial vaginosis, since the ultimate cause of the disease is not yet known. There are a variety of methods for the diagnosis of bacterial vaginosis but no method can at present be regarded as the best. Diagnosing bacterial vaginosis has long been based on the clinical criteria of Amsel, whereby three of four defined criteria must be satisfied. Nugent's scoring system has been further developed and includes validation of the categories of observable bacteria structures. Up-to-date molecular tests are introduced, and better understanding of vaginal microbiome, a clear definition for bacterial vaginosis, and short-term and long-term fluctuations in vaginal microflora will help to better define molecular tests within the broader clinical context.

  17. Bacterial Vaginosis

    Science.gov (United States)

    ... Archive STDs Home Page Bacterial Vaginosis (BV) Chlamydia Gonorrhea Genital Herpes Hepatitis HIV/AIDS & STDs Human Papillomavirus ( ... of getting other STDs, such as chlamydia and gonorrhea . These bacteria can sometimes cause pelvic inflammatory disease ( ...

  18. Optimization and evaluation of Flexicult® Vet for detection, identification and antimicrobial susceptibility testing of bacterial uropathogens in small animal veterinary practice.

    Science.gov (United States)

    Guardabassi, Luca; Hedberg, Sandra; Jessen, Lisbeth Rem; Damborg, Peter

    2015-10-26

    Urinary tract infection (UTI) is a common reason for antimicrobial prescription in dogs and cats. The objective of this study was to optimize and evaluate a culture-based point-of-care test for detection, identification and antimicrobial susceptibility testing of bacterial uro-pathogens in veterinary practice. Seventy-two urine samples from dogs and cats with suspected UTI presenting to seven veterinary facilities were used by clinical staff and an investigator to estimate sensitivity and specificity of Flexicult Vet A compared to laboratory reference standards for culture and susceptibility testing. Subsequently, the test was modified by inclusion of an oxacillin-containing compartment for detection of methicillin-resistant staphylococci. The performance of the modified product (Flexicult Vet B) for susceptibility testing was evaluated in vitro using a collection of 110 clinical isolates. Bacteriuria was reported by the laboratory in 25 (35 %) samples from the field study. The sensitivity and specificity of Flexicult Vet A for detection of bacteriuria were 83 and 100 %, respectively. Bacterial species were correctly identified in 53 and 100 % of the positive samples by clinical staff and the investigator, respectively. The susceptibility results were interpreted correctly by clinical staff for 70 % of the 94 drug-strain combinations. Higher percentages of correct interpretation were observed when the results were interpreted by the investigator in both the field (76 %) and the in vitro study (94 %). The most frequent errors were false resistance to β-lactams (ampicillin, amoxicillin-clavulanate and cephalotin) in Escherichia coli for Flexicult Vet A, and false amoxicillin-clavulanate resistance in E. coli and false ampicillin susceptibility in Staphylococcus pseudintermedius for Flexicult Vet B. The latter error can be prevented by categorizing staphylococcal strains growing in the oxacillin compartment as resistant to all β-lactams. Despite the

  19. Comparison of in vitro test systems using bacterial and mammalian cells for genotoxicity assessment within the "health-related indication value (HRIV) concept.

    Science.gov (United States)

    Prantl, Eva-Maria; Kramer, Meike; Schmidt, Carsten K; Knauer, Martina; Gartiser, Stefan; Shuliakevich, Aliaksandra; Milas, Julia; Glatt, Hansruedi; Meinl, Walter; Hollert, Henner

    2018-02-01

    information and may give a first indication of the mechanism of action. To check this hypothesis, various additional strains expressing specific human-relevant enzymes were investigated. It could be shown that the additional use of genetically modified tester strains can enhance the detectable substance spectrum with the bacterial genotoxicological standard procedures or increase the sensitivity. The additional use provides orienting information at this level as a lot of data can be obtained quite quickly and with little effort. These indications of the mechanism of action should be however verified with a test system that uses mammalian cells, better human cells, to check their actual relevance. The selection of appropriate additional tester strains has to be defined from case to case depending on the molecular structure and also still requires some major expertise.

  20. The opiate sufentanil alters the inflammatory, endocrine, and metabolic responses to endotoxin in dogs

    NARCIS (Netherlands)

    Moeniralam, H. S.; Endert, E.; Ackermans, M. T.; van Lanschot, J. J.; Sauerwein, H. P.; Romijn, J. A.

    1998-01-01

    Sufentanil is a synthetic mu-opioid receptor agonist frequently used in anesthesia and critically ill patients. To evaluate the effects of sufentanil on the inflammatory, neuroendocrine, and metabolic responses to endotoxin, we studied six dogs during saline infusion (control), during sufentanil

  1. Efficacy of an extracorporeal endotoxin adsorber system during hyperdynamic porcine endotoxemia.

    Science.gov (United States)

    Bracht, H; Hauser, B; Ivanyi, Z; Asfar, P; Ehrmann, U; Brueckner, U B; Georgieff, M; Radermacher, P; Buttenschon, K

    2009-01-01

    Endotoxemia is a crucial factor in the pathogenesis of sepsis. Elimination of endotoxin is aimed at the reduction of sepsis-related morbidity and lethality. The objective of this study was to examine the impact of an endotoxin adsorber on hemodynamics, O(2) exchange and metabolism during resuscitated porcine endotoxemia. Twenty pigs were randomized into 2 intervention groups (n = 7 each) and 1 control group (n = 6). Endotoxemia was induced by continuous intravenous application of lipopolysaccharide for 8 h. Adsorber therapy was started at the same time as the induction of endotoxemia or 2 h later. An extracorporeal hemoperfusion device using immobilized human serum albumin for endotoxin adsorption was used. Hemodynamic, metabolic and acid-base parameters, as well as the kinetics of interleukin (IL)-6, IL-8, IL-10 and tumor necrosis factor-alpha, were characteristic for endotoxic shock. Endotoxin plasma levels were low (arterial, hepatic and portal vein). None of the parameters were significantly influenced by the adsorber system. Despite typical clinical signs of endotoxemia, the adsorber system had no significant effect on hemodynamic, metabolic and acid-base parameters during endotoxic shock. The reasons for the absence of an effect are elusive; however, failure of the method per se or exceeded capacity of the adsorber cannot be excluded. Copyright (c) 2009 S. Karger AG, Basel.

  2. Pharmacological modulation of the endotoxin-induced increase in plasminogen activator inhibitor activity in rats

    NARCIS (Netherlands)

    Emeis, J.J.; Hoogen, C.M. van den

    1992-01-01

    Pharmacological modulation of the in vivo induction of plasminogen activator inhibitor type-1 (PAI-1) synthesis was studied in rats using the induction of PAI-1 by endotoxin as a model system. Both the cyclooxygenase inhibitors acetylsalicylic acid and indomethacin enhanced PAI-1 induction. The

  3. Determination of the plasmid size and location of d-endotoxin genes ...

    African Journals Online (AJOL)

    The genes encoding the d-endotoxins of Bacillus thuringiensis are located on plasmids ranging in size from 45 to 1000 kb. Plasmid size and variety are diagnostic features for characterizing subspecies of this aerobic spore-forming crystalliferous entomopathogen. Two of 25 B. thuringiensis isolates obtained from Middle ...

  4. Effect of enrofloxacin treatment on plasma endotoxin during bovine Escherichia coli mastitis

    NARCIS (Netherlands)

    Dosogne, H.; Meyer, E.; Sturk, A.; van Loon, J.; Massart-Leën, A. M.; Burvenich, C.

    2002-01-01

    OBJECTIVE AND DESIGN: To investigate the effect of enrofloxacin on endotoxin resorption during bovine Escherichia coli mastitis. ANIMALS: 12 healthy early post partum Holstein cows. TREATMENT: Mastitis was induced by intramammary infusion of 10(4) cfu E. coli P4:032. Six cows were treated twice

  5. NAD+-dependent SIRT1 deacetylase participates in epigenetic reprogramming during endotoxin tolerance.

    Science.gov (United States)

    Liu, Tie Fu; Yoza, Barbara K; El Gazzar, Mohamed; Vachharajani, Vidula T; McCall, Charles E

    2011-03-18

    Gene-selective epigenetic reprogramming and shifts in cellular bioenergetics develop when Toll-like receptors (TLR) recognize and respond to systemic life-threatening infections. Using a human monocyte cell model of endotoxin tolerance and human leukocytes from acute systemic inflammation with sepsis, we report that energy sensor sirtuin 1 (SIRT1) coordinates the epigenetic and bioenergy shifts. After TLR4 signaling, SIRT1 rapidly accumulated at the promoters of TNF-α and IL-1β, but not IκBα; SIRT1 promoter binding was dependent on its co-factor, NAD(+). During this initial process, SIRT1 deacetylated RelA/p65 lysine 310 and nucleosomal histone H4 lysine 16 to promote termination of NFκB-dependent transcription. SIRT1 then remained promoter bound and recruited de novo induced RelB, which directed assembly of the mature transcription repressor complex that generates endotoxin tolerance. SIRT1 also promoted de novo expression of RelB. During sustained endotoxin tolerance, nicotinamide phosphoribosyltransferase (Nampt), the rate-limiting enzyme for endogenous production of NAD(+), and SIRT1 expression increased. The elevation of SIRT1 required protein stabilization and enhanced translation. To support the coordination of bioenergetics in human sepsis, we observed elevated NAD(+) levels concomitant with SIRT1 and RelB accumulation at the TNF-α promoter of endotoxin tolerant sepsis blood leukocytes. We conclude that TLR4 stimulation and human sepsis activate pathways that couple NAD(+) and its sensor SIRT1 with epigenetic reprogramming.

  6. Endotoxin-induced liver damage in rats is minimized by beta 2-adrenoceptor stimulation.

    NARCIS (Netherlands)

    Izeboud, C.A.; Hoebe, K.H.; Grootendorst, A.F.; Nijmeijer, S.M.; Miert, A.S. van; Witkamp, R.R.; Rodenburg, R.J.T.

    2004-01-01

    OBJECTIVE AND DESIGN: To investigate the effects of beta(2)-adrenoceptor (beta(2)-AR) stimulation on endotoxin-induced liver damage and systemic cytokine levels in rats. SUBJECTS: Standard male Wistar rats. TREATMENT: A disease-model of lipopolysaccharide (LPS)-induced acute systemic inflammation

  7. Endotoxin-induced liver damage in rats is minimized by β2- adrenoceptor stimulation

    NARCIS (Netherlands)

    Izeboud, C.A.; Hoebe, K.H.N.; Grootendorst, A.F.; Nijmeijer, S.M.; Miert, A.S. van; Witkamp, R.F.; Rodenburg, R.J.T.

    2004-01-01

    Objective and Design: To investigate the effects of β2- adrenoceptor (β2-AR) stimulation on endotoxin-induced liver damage and systemic cytokine levels in rats. Subjects: Standard male Wistar rats. Treatment: A disease-model of lipolysaccharide (LPS)-induced acute systemic inflammation was used. The

  8. Modulation of reactive oxygen species production alters responses of lung inflammatory cells to endotoxin

    Czech Academy of Sciences Publication Activity Database

    Krejčová, Daniela; Konopka, Roman; Lojek, Antonín; Číž, Milan; Kubala, Lukáš

    2006-01-01

    Roč. 40, č. 1 (2006), S112-S112 ISSN 1071-5762 R&D Projects: GA ČR(CZ) GA524/06/1197 Institutional research plan: CEZ:AV0Z50040507 Keywords : myeloperoxidase * inflammation * endotoxin Subject RIV: BO - Biophysics

  9. REPRODUCTIVE CONDITION, GLOMERULAR ADENOSINE DIPHOSPHATASE ACTIVITY, AND PLATELET-AGGREGATION IN THE RAT - EFFECT OF ENDOTOXIN

    NARCIS (Netherlands)

    VISSCHER, CA; FAAS, MM; BAKKER, WW; SCHUILING, GA

    1993-01-01

    In experiment A, the activity of the glomerular antithrombotic enzyme adenosine diphosphatase (ADPase) and the sensitivity of this enzyme for endotoxin (1.0 mug/kg BW) in various reproductive conditions of female rats were studied through use of enzyme histochemical methods. In experiment B, the

  10. Endotoxin levels in settled airborne dust in European schools : The HITEA school study

    NARCIS (Netherlands)

    Jacobs, J. H.; Krop, E. J M; Borras-Santos, A.; Zock, J. P.; Taubel, M.; Hyvarinnen, A.; Pekkanen, J.; Doekes, G.; Heederik, D. J J

    2014-01-01

    Indoor exposure to microbial agents is known to influence respiratory health. Besides home exposure, exposure in schools can affect respiratory health. In this study, we measured endotoxin in settled dust in primary schools in three European countries from three different geographical regions with

  11. Effect of plasmapheresis on the immune system in endotoxin-induced sepsis

    DEFF Research Database (Denmark)

    Toft, P; Schmidt, R; Broechner, A C

    2008-01-01

    BACKGROUND: It has been proposed that plasmapheresis is most effective when applied early in Gram-negative sepsis. We therefore studied the effect of early plasmapheresis on immunity in experimental Escherichia coli endotoxin-induced sepsis. METHODS: 20 pigs received 30 microg/kg of E. coli...

  12. Effects of Bacillus thuringiensis CRY1A(c) δ-endotoxin on growth ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-01-04

    Jan 4, 2010 ... The recent introduction of Bt maize and Bt cotton transgenic crops into Africa has raised concerns on their potential short and long-term ecological effects on the environment. The effects of Bacillus thuringiensis (Bt) Cry1A(c) δ-endotoxin on the growth, nodulation and productivity of two leguminous.

  13. Effects of Bacillus thuringiensis CRY1A(c) d-endotoxin on growth ...

    African Journals Online (AJOL)

    The recent introduction of Bt maize and Bt cotton transgenic crops into Africa has raised concerns on their potential short and long-term ecological effects on the environment. The effects of Bacillus thuringiensis (Bt) Cry1A(c) d-endotoxin on the growth, nodulation and productivity of two leguminous plants grown in clay soil ...

  14. Endotoxin-induced uveitis in the rat. The significance of intraocular interleukin-6

    NARCIS (Netherlands)

    Hoekzema, R.; Verhagen, C.; van Haren, M.; Kijlstra, A.

    1992-01-01

    The potential role of interleukin-6 (IL-6) was studied as an inflammatory mediator of endotoxin (or lipopolysaccharide [LPS])-induced uveitis (EIU) in the rat. In young Lewis rats, levels of intraocular IL-6, but not serum IL-6, correlated with the severity of uveitis and with aqueous humor protein

  15. Endotoxin induces fibrosis in vascular endothelial cells through a mechanism dependent on transient receptor protein melastatin 7 activity.

    Directory of Open Access Journals (Sweden)

    Cesar Echeverría

    Full Text Available The pathogenesis of systemic inflammatory diseases, including endotoxemia-derived sepsis syndrome, is characterized by endothelial dysfunction. It has been demonstrated that the endotoxin lipopolysaccharide (LPS induces the conversion of endothelial cells (ECs into activated fibroblasts through endothelial-to-mesenchymal transition mechanism. Fibrogenesis is highly dependent on intracellular Ca2+ concentration increases through the participation of calcium channels. However, the specific molecular identity of the calcium channel that mediates the Ca2+ influx during endotoxin-induced endothelial fibrosis is still unknown. Transient receptor potential melastatin 7 (TRPM7 is a calcium channel that is expressed in many cell types, including ECs. TRPM7 is involved in a number of crucial processes such as the conversion of fibroblasts into activated fibroblasts, or myofibroblasts, being responsible for the development of several characteristics of them. However, the role of the TRPM7 ion channel in endotoxin-induced endothelial fibrosis is unknown. Thus, our aim was to study whether the TRPM7 calcium channel participates in endotoxin-induced endothelial fibrosis. Using primary cultures of ECs, we demonstrated that TRPM7 is a crucial protein involved in endotoxin-induced endothelial fibrosis. Suppression of TRPM7 expression protected ECs from the fibrogenic process stimulated by endotoxin. Downregulation of TRPM7 prevented the endotoxin-induced endothelial markers decrease and fibrotic genes increase in ECs. In addition, TRPM7 downregulation abolished the endotoxin-induced increase in ECM proteins in ECs. Furthermore, we showed that intracellular Ca2+ levels were greatly increased upon LPS challenge in a mechanism dependent on TRPM7 expression. These results demonstrate that TRPM7 is a key protein involved in the mechanism underlying endotoxin-induced endothelial fibrosis.

  16. Endotoxin induced chorioamnionitis prevents intestinal development during gestation in fetal sheep.

    Directory of Open Access Journals (Sweden)

    Tim G A M Wolfs

    Full Text Available Chorioamnionitis is the most significant source of prenatal inflammation and preterm delivery. Prematurity and prenatal inflammation are associated with compromised postnatal developmental outcomes, of the intestinal immune defence, gut barrier function and the vascular system. We developed a sheep model to study how the antenatal development of the gut was affected by gestation and/or by endotoxin induced chorioamnionitis.Chorioamnionitis was induced at different gestational ages (GA. Animals were sacrificed at low GA after 2d or 14d exposure to chorioamnionitis. Long term effects of 30d exposure to chorioamnionitis were studied in near term animals after induction of chorioamnionitis. The cellular distribution of tight junction protein ZO-1 was shown to be underdeveloped at low GA whereas endotoxin induced chorioamnionitis prevented the maturation of tight junctions during later gestation. Endotoxin induced chorioamnionitis did not induce an early (2d inflammatory response in the gut in preterm animals. However, 14d after endotoxin administration preterm animals had increased numbers of T-lymphocytes, myeloperoxidase-positive cells and gammadelta T-cells which lasted till 30d after induction of chorioamnionitis in then near term animals. At early GA, low intestinal TLR-4 and MD-2 mRNA levels were detected which were further down regulated during endotoxin-induced chorioamnionitis. Predisposition to organ injury by ischemia was assessed by the vascular function of third-generation mesenteric arteries. Endotoxin-exposed animals of low GA had increased contractile response to the thromboxane A2 mimetic U46619 and reduced endothelium-dependent relaxation in responses to acetylcholine. The administration of a nitric oxide (NO donor completely restored endothelial dysfunction suggesting reduced NO bioavailability which was not due to low expression of endothelial nitric oxide synthase.Our results indicate that the distribution of the tight

  17. Trajectory of inflammatory and microglial activation markers in the postnatal rabbit brain following intrauterine endotoxin exposure.

    Science.gov (United States)

    Zhang, Zhi; Jyoti, Amar; Balakrishnan, Bindu; Williams, Monica; Singh, Sarabdeep; Chugani, Diane C; Kannan, Sujatha

    2018-03-01

    Maternal infection is a risk factor for periventricular leukomalacia and cerebral palsy (CP) in neonates. We have previously demonstrated hypomyelination and motor deficits in newborn rabbits, as seen in patients with cerebral palsy, following maternal intrauterine endotoxin administration. This was associated with increased microglial activation, primarily involving the periventricular region (PVR). In this study we hypothesized that maternal intrauterine inflammation leads to a pro-inflammatory environment in the PVR that is associated with microglial activation in the first 2 postnatal weeks. Timed pregnant New Zealand white rabbits underwent laparotomy on gestational day 28 (G28). They were randomly divided to receive lipopolysaccharide (LPS; 20μg/kg in 1mL saline) (Endotoxin group) or saline (1mL) (control saline, CS group), administrated along the wall of the uterus. The PVR from the CS and Endotoxin kits were harvested at G29 (1day post-injury), postnatal day1 (PND1, 3day post-injury) and PND5 (7days post-injury) for real-time PCR, ELISA and immunohistochemistry. Kits from CS and Endotoxin groups underwent longitudinal MicroPET imaging, with [ 11 C]PK11195, a tracer for microglial activation. We found that intrauterine endotoxin exposure resulted in pro-inflammatory microglial activation in the PVR of rabbits in the first postnatal week. This was evidenced by increased TSPO (translocator protein) expression co-localized with microglia/macrophages in the PVR, and changes in the microglial morphology (ameboid soma and retracted processes). In addition, CD11b level significantly increased with a concomitant decline in the CD45 level in the PVR at G29 and PND1. There was a significant elevation of pro-inflammatory cytokines and iNOS, and decreased anti-inflammatory markers in the Endotoxin kits at G29, PND1 and PND5. Increased [ 11 C]PK11195 binding to the TSPO measured in vivo by PET imaging in the brain of Endotoxin kits was present up to PND14-17. Our

  18. Piroxicam Reverses Endotoxin-Induced Hypotension in Rats: Contribution of Vasoactive Eicosanoids and Nitric Oxide

    Science.gov (United States)

    Buharalioglu, C. Kemal; Korkmaz, Belma; Cuez, Tuba; Sahan-Firat, Seyhan; Sari, Ayşe Nihal; Malik, Kafait U.; Tunctan, Bahar

    2011-01-01

    Nitric oxide (NO) produced by inducible NO synthase (iNOS) is responsible for endotoxin-induced vascular hyporeactivity and hypotension resulting in multiple organ failure. Endotoxic shock is also characterized by decreased expression of constitutive cyclooxygenase (COX-1), cytochrome P450 (CYP) 4A and endothelial NOS (eNOS). Our previous studies demonstrated that dual inhibition of iNOS and COX with a selective COX-2 inhibitor, NS-398, or a non-selective COX inhibitor, indomethacin, restores blood pressure presumably due to increased production of 20-hydroxyeicosatetraenoic acid (20-HETE) derived from arachidonic acid (AA) by CYP4A in endotoxaemic rats. The aim of this study was to investigate the effects of piroxicam, a preferential COX-1 inhibitor, on the endotoxin-induced changes in blood pressure, expression of COX-1, inducible COX (COX-2), CYP4A1, eNOS, iNOS and heat shock protein 90 (hsp90), and production of PGI2, PGE2, 20-HETE and NO. Injection of endotoxin (10 mg/kg, i.p.) to male Wistar rats caused a fall in blood pressure and an increase in heart rate associated with elevated renal 6-keto-PGF1α and PGE2 levels as well as an increase in COX-2 protein expression. Endotoxin also caused an elevation in systemic and renal nitrite levels associated with increased renal iNOS protein expression. In contrast, systemic and renal 20-HETE levels and renal expression of eNOS, COX-1 and CYP4A1 were decreased in endotoxaemic rats. The effects of endotoxin, except for renal COX-1 and eNOS protein expression, were prevented by piroxicam (10 mg/kg, i.p.), given 1 hr after injection of endotoxin. Endotoxin did not change renal hsp90 protein expression. These data suggest that a decrease in the expression and activity of COX-2 and iNOS associated with an increase in CYP4A1 expression and 20-HETE synthesis contributes to the effect of piroxicam to prevent the hypotension during rat endotoxaemia. PMID:21463481

  19. Filter Efficiency and Leak Testing of Returned ISS Bacterial Filter Elements After 2.5 Years of Continuous Operation

    Science.gov (United States)

    Green, Robert D.; Agui, Juan H.; Berger, Gordon M.; Vijayakumar, R.; Perry, Jay L.

    2016-01-01

    The atmosphere revitalization equipment aboard the International Space Station (ISS) and future deep space exploration vehicles provides the vital functions of maintaining a habitable environment for the crew as well as protecting the hardware from fouling by suspended particulate matter. Providing these functions are challenging in pressurized spacecraft cabins because no outside air ventilation is possible and a larger particulate load is imposed on the filtration system due to lack of sedimentation in reduced gravity conditions. The ISS Environmental Control and Life Support (ECLS) system architecture in the U.S. Segment uses a distributed particulate filtration approach consisting of traditional High-Efficiency Particulate Adsorption (HEPA) filters deployed at multiple locations in each module. These filters are referred to as Bacteria Filter Elements (BFEs). As more experience has been gained with ISS operations, the BFE service life, which was initially one year, has been extended to two to five years, dependent on the location in the U.S. Segment. In previous work we developed a test facility and test protocol for leak testing the ISS BFEs. For this work, we present results of leak testing a sample set of returned BFEs with a service life of 2.5 years, along with particulate removal efficiency and pressure drop measurements. The results can potentially be utilized by the ISS Program to ascertain whether the present replacement interval can be maintained or extended to balance the on-ground filter inventory with extension of the lifetime of ISS to 2024. These results can also provide meaningful guidance for particulate filter designs under consideration for future deep space exploration missions.

  20. Lung responses to secondary endotoxin challenge in rats exposed to pig barn air

    Directory of Open Access Journals (Sweden)

    Townsend Hugh GG

    2008-10-01

    Full Text Available Abstract Background Swine barn air contains endotoxin and many other noxious agents. Single or multiple exposures to pig barn air induces lung inflammation and loss of lung function. However, we do not know the effect of exposure to pig barn air on inflammatory response in the lungs following a secondary infection. Therefore, we tested a hypothesis that single or multiple exposures to barn air will result in exaggerated lung inflammation in response to a secondary insult with Escherichia coli LPS (E. coli LPS. Methods We exposed Sprague-Dawley rats to ambient (N = 12 or swine barn air (N = 24 for one or five days and then half (N = 6/group of these rats received intravenous E. coli LPS challenge, observed for six hours and then euthanized to collect lung tissues for histology, immunohistochemistry and ELISA to assess lung inflammation. Results Compared to controls, histological signs of lung inflammation were evident in barn exposed rat lungs. Rats exposed to barn air for one or five days and challenged with E. coli LPS showed increased recruitment of granulocytes compared to those exposed only to the barn. Control, one and five day barn exposed rats that were challenged with E. coli LPS showed higher levels of IL-1β in the lungs compared to respective groups not challenged with E. coli LPS. The levels of TNF-α in the lungs did not differ among any of the groups. Control rats without E. coli LPS challenge showed higher levels of TGF-β2 compared to controls challenged with E. coli LPS. Conclusion These results show that lungs of rats exposed to pig barn air retain the ability to respond to E. coli LPS challenge.

  1. Small intestinal bacterial overgrowth as an uncommon cause of false positive lactose hydrogen breath test among patients with diarrhea-predominant irritable bowel syndrome in Asia.

    Science.gov (United States)

    Wang, Yilin; Xiong, Lishou; Gong, Xiaorong; Li, Weimin; Zhang, Xiangsong; Chen, Minhu

    2015-06-01

    It has been reported that small intestinal bacterial overgrowth (SIBO) may lead to false positive diagnoses of lactose malabsorption (LM) in irritable bowel syndrome patients. The aim of this study was to determine the influence of SIBO on lactose hydrogen breath test (HBT) results in these patients. Diarrhea-predominant irritable bowel syndrome patients with abnormal lactose HBTs ingested a test meal containing (99m) Tc and lactose. The location of the test meal and the breath levels of hydrogen were recorded simultaneously by scintigraphic scanning and lactose HBT, respectively. The increase in hydrogen concentration was not considered to be caused by SIBO if ≥ 10% of (99m) Tc accumulated in the cecal region at the time or before of abnormal lactose HBT. LM was present in 84% (31/37) of irritable bowel syndrome patients. Twenty of these patients agreed to measurement of oro-cecal transit time. Only three patients (15%) with abnormal lactose HBT might have had SIBO. The median oro-cecal transit time between LM and lactose intolerance patients were 75 min and 45 min, respectively (Z=2.545, P=0.011). Most of irritable bowel syndrome patients with an abnormal lactose HBT had LM. SIBO had little impact on the interpretation of lactose HBTs. The patients with lactose intolerance had faster small intestinal transit than LM patients. © 2014 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.

  2. Physicochemical characterization of the endotoxins from Coxiella burnetii strain Priscilla in relation to their bioactivities

    Directory of Open Access Journals (Sweden)

    Hussein Ahmed

    2004-01-01

    Full Text Available Abstract Background Coxiella burnetii is the etiological agent of Q fever found worldwide. The microorganism has like other Gram-negative bacteria a lipopolysaccharide (LPS, endotoxin in its outer membrane, which is important for the pathogenicity of the bacteria. In order to understand the biological activity of LPS, a detailed physico-chemical analysis of LPS is of utmost importace. Results The lipid A moiety of LPS is tetraacylated and has longer (C-16 acyl chains than most other lipid A from enterobacterial strains. The two ester-linked 3-OH fatty acids found in the latter are lacking. The acyl chains of the C. burnetii endotoxins exhibit a broad melting range between 5 and 25°C for LPS and 10 and 40°C for lipid A. The lipid A moiety has a cubic inverted aggregate structure, and the inclination angle of the D-glucosamine disaccharide backbone plane of the lipid A part with respect to the membrane normal is around 40°. Furthermore, the endotoxins readily intercalate into phospholipid liposomes mediated by the lipopolysaccharide-binding protein (LBP. The endotoxin-induced tumor necrosis factor α (TNFα production in human mononuclear cells is one order of magnitude lower than that found for endotoxins from enterobacterial strains, whereas the same activity as in the latter compounds is found in the clotting reaction of the Limulus amebocyte lysate assay. Conclusions Despite a considerably different chemical primary structure of the C. burnetii lipid A in comparison with enterobacterial lipid A, the data can be well understood by applying the previously presented conformational concept of endotoxicity, a conical shape of the lipid A moiety of LPS and a sufficiently high inclination of the sugar backbone plane with respect to the membrane plane. Importantly, the role of the acyl chain fluidity in modulating endotoxicity now becomes more evident.

  3. Advances in diagnostic tests for bacterial STDs Avances en las pruebas diagnósticas de ETS bacterianas

    Directory of Open Access Journals (Sweden)

    Stephen A Morse

    2003-01-01

    Full Text Available Because of their asymptomatic nature and nonspecific symptoms, laboratory tests are often required to diagnose a sexually transmitted infection. Over the past few years, there have been advances in technology, such as the development of nucleic acid amplification assays, which have improved our ability to diagnose infections caused by Chlamydia trachomatis. The finding that nucleic acid amplification tests can detect more infected individuals and are useful in screening low prevalence populations, has led to the development of strategies designed to reduce the cost of these assays without significantly impacting their sensitivity. The development of new tests for the diagnosis of syphilis has gained momentum from the report of a synthetic VDRL antigen, which will result in better nontreponemal antibody tests for syphilis. In spite of the completion of the genome sequence of Treponema pallidum and its annotation, we are still unable to cultivate this microorganism in vitro. However, the molecular revolution has resulted in the development of PCR assays for detecting Treponema pallidum in various types of clinical specimens, and to the production of recombinant antigens for use in tests that detect treponemal-specific antibodies. Further research will improve the availability of low cost, sensitive tests for the diagnosis of sexually transmitted infections.Las pruebas de laboratorio son necesarias a menudo para el diagnóstico de las infecciones transmitidas sexualmente, debido a la naturaleza asintomática o a la presencia de síntomas inespecíficos de esas infecciones. En este sentido, durante los años relativamente recientes se han registrado importantes avances tecnológicos, como por ejemplo los ensayos de amplificación de ácidos nucleicos que han permitido una mejora en la posibilidad de diagnosticar las infecciones causadas por Chlamydia trachomatis. El descubrimiento de que las pruebas de amplificación de ácidos nucleicos permiten

  4. Proficiency Testing for Bacterial Whole Genome Sequencing: An End-User Survey of Current Capabilities, Requirements and Priorities

    DEFF Research Database (Denmark)

    Moran-Gilad, Jacob; Sintchenko, Vitali; Karlsmose Pedersen, Susanne

    2015-01-01

    The advent of next-generation sequencing (NGS) has revolutionised public health microbiology. Given the potential impact of NGS, it is paramount to ensure standardisation of ‘wet’ laboratory and bioinformatic protocols and promote comparability of methods employed by different laboratories...... and their outputs. Therefore, one of the ambitious goals of the Global Microbial Identifier (GMI) initiative (http://​www.​globalmicrobiali​dentifier.​org/​) has been to establish a mechanism for inter-laboratory NGS proficiency testing (PT). This report presents findings from the survey recently conducted...

  5. Proficiency testing for bacterial whole genome sequencing: an end-user survey of current capabilities, requirements and priorities

    DEFF Research Database (Denmark)

    Moran-Gilad, Jacob; Sintchenko, Vitali; Karlsmose Pedersen, Susanne

    2015-01-01

    The advent of next-generation sequencing (NGS) has revolutionised public health microbiology. Given the potential impact of NGS, it is paramount to ensure standardisation of 'wet' laboratory and bioinformatic protocols and promote comparability of methods employed by different laboratories...... and their outputs. Therefore, one of the ambitious goals of the Global Microbial Identifier (GMI) initiative (http://www.globalmicrobialidentifier.org/) has been to establish a mechanism for inter-laboratory NGS proficiency testing (PT). This report presents findings from the survey recently conducted by Working...

  6. BACTERIAL CONSORTIUM

    Directory of Open Access Journals (Sweden)

    Payel Sarkar

    2013-01-01

    Full Text Available Petroleum aromatic hydrocarbons like benzen e, toluene, ethyl benzene and xylene, together known as BTEX, has almost the same chemical structure. These aromatic hydrocarbons are released as pollutants in th e environment. This work was taken up to develop a solvent tolerant bacterial cons ortium that could degrade BTEX compounds as they all share a common chemical structure. We have isolated almost 60 different types of bacterial strains from different petroleum contaminated sites. Of these 60 bacterial strains almost 20 microorganisms were screene d on the basis of capability to tolerate high concentration of BTEX. Ten differe nt consortia were prepared and the compatibility of the bacterial strains within the consortia was checked by gram staining and BTEX tolerance level. Four successful mi crobial consortia were selected in which all the bacterial strains concomitantly grew in presence of high concentration of BTEX (10% of toluene, 10% of benzene 5% ethyl benzene and 1% xylene. Consortium #2 showed the highest growth rate in pr esence of BTEX. Degradation of BTEX by consortium #2 was monitored for 5 days by gradual decrease in the volume of the solvents. The maximum reduction observed wa s 85% in 5 days. Gas chromatography results also reveal that could completely degrade benzene and ethyl benzene within 48 hours. Almost 90% degradation of toluene and xylene in 48 hours was exhibited by consortium #2. It could also tolerate and degrade many industrial solvents such as chloroform, DMSO, acetonitrile having a wide range of log P values (0.03–3.1. Degradation of aromatic hydrocarbon like BTEX by a solvent tolerant bacterial consortium is greatly significant as it could degrade high concentration of pollutants compared to a bacterium and also reduces the time span of degradation.

  7. Characterization of the bacterial and fungal microbiome in indoor dust and outdoor air samples: a pilot study���

    OpenAIRE

    Hanson, Blake; Zhou, Yanjiao; Bautista, Eddy J.; Urch, Bruce; Speck, Mary; Silverman, Frances; Muilenberg, Michael; Phipatanakul, Wanda; Weinstock, George; Sodergren, Erica; Gold, Diane R.; Sordillo, Joanne E.

    2016-01-01

    Environmental microbes have been associated with both protective and adverse health effects in children and adults. Epidemiological studies often rely on broad biomarkers of microbial exposure (i.e. endotoxin, 1���3, Beta-D glucan), but fail to identify the taxonomic composition of the microbial community. Our aim was to characterize the bacterial and fungal microbiome in different types of environmental samples collected in studies of human health effects. We determined the composition of mi...

  8. The effects of culture independent diagnostic testing on the diagnosis and reporting of enteric bacterial pathogens in Queensland, 2010 to 2014.

    Science.gov (United States)

    May, Fiona J; Stafford, Russell J; Carroll, Heidi; Robson, Jennifer Mb; Vohra, Renu; Nimmo, Graeme R; Bates, John; Kirk, Martyn D; Fearnley, Emily J; Polkinghorne, Benjamin G

    2017-09-01

    Changes in diagnostic laboratory testing procedures can impact on the number of cases notified and the public health surveillance of enteric pathogens. Culture independent diagnostic testing using a multiplex polymerase chain reaction (PCR) test was introduced for the rapid detection of bacterial enteric pathogens in pathology laboratories in Queensland, Australia, from late 2013 onwards. We conducted a retrospective descriptive study using laboratory data to assess the impact of the introduction of PCR testing on four common enteric pathogens, Salmonella, Campylobacter, Shigella and Yersinia, in Queensland between 2010 and 2014. The number of stool specimens tested and the proportion positive for each of the four pathogens increased in 2014 after the introduction of culture independent diagnostic testing. Among the specimens tested by both PCR and culture, 12% of Salmonella positive stools, 36% of Campylobacter positive stools, 74% of Shigella / enteroinvasive Escherichia coli positive stools and 65% of Yersinia positive stools were PCR positive only. Including those where culture was not performed, 19% of Salmonella positive stools, 44% of Campylobacter positive stools, 83% of Shigella positive stools and 79% of Yersinia positive stools had no cultured isolate available for further characterisation. The detection and tracking of foodborne and non-foodborne gastrointestinal outbreaks will become more difficult as culture independent diagnostic testing becomes more widespread. Until new techniques for characterisation of pathogens directly from clinical specimens have been developed, we recommend laboratories continue to culture specimens concurrently or reflexively with culture independent diagnostic tests. This work is copyright. You may download, display, print and reproduce the whole or part of this work in unaltered form for your own personal use or, if you are part of an organisation, for internal use within your organisation, but only if you or your

  9. Evaluation of the Effect of the Volume Throughput and Maximum Flux of Low-Surface-Tension Fluids on Bacterial Penetration of 0.2 Micron-Rated Filters during Process-Specific Filter Validation Testing.

    Science.gov (United States)

    Folmsbee, Martha

    2015-01-01

    Approximately 97% of filter validation tests result in the demonstration of absolute retention of the test bacteria, and thus sterile filter validation failure is rare. However, while Brevundimonas diminuta (B. diminuta) penetration of sterilizing-grade filters is rarely detected, the observation that some fluids (such as vaccines and liposomal fluids) may lead to an increased incidence of bacterial penetration of sterilizing-grade filters by B. diminuta has been reported. The goal of the following analysis was to identify important drivers of filter validation failure in these rare cases. The identification of these drivers will hopefully serve the purpose of assisting in the design of commercial sterile filtration processes with a low risk of filter validation failure for vaccine, liposomal, and related fluids. Filter validation data for low-surface-tension fluids was collected and evaluated with regard to the effect of bacterial load (CFU/cm(2)), bacterial load rate (CFU/min/cm(2)), volume throughput (mL/cm(2)), and maximum filter flux (mL/min/cm(2)) on bacterial penetration. The data set (∼1162 individual filtrations) included all instances of process-specific filter validation failures performed at Pall Corporation, including those using other filter media, but did not include all successful retentive filter validation bacterial challenges. It was neither practical nor necessary to include all filter validation successes worldwide (Pall Corporation) to achieve the goals of this analysis. The percentage of failed filtration events for the selected total master data set was 27% (310/1162). Because it is heavily weighted with penetration events, this percentage is considerably higher than the actual rate of failed filter validations, but, as such, facilitated a close examination of the conditions that lead to filter validation failure. In agreement with our previous reports, two of the significant drivers of bacterial penetration identified were the total

  10. Atmospheric pressure plasma jet for bacterial decontamination and property improvement of fruit and vegetable processing wastewater

    Science.gov (United States)

    Mohamed, Abdel-Aleam H.; Shariff, Samir M. Al; Ouf, Salama A.; Benghanem, Mohamed

    2016-05-01

    An atmospheric pressure plasma jet was tested for decontaminating and improving the characteristics of wastewater derived from blackberry, date palm, tomato and beetroot processing industries. The jet was generated by blowing argon gas through a cylindrical alumina tube while a high voltage was applied between two electrodes surrounding the tube. Oxygen gas was mixed with argon at the rate of 0.2% and the argon mass flow was fixed at 4.5 slm. Images show that the generated plasma jet penetrated the treated wastewater samples. Plasma emission spectra show the presence of O and OH radicals as well as excited molecular nitrogen and argon. Complete decontamination of wastewater derived from date palm and tomato processing was achieved after 120 and 150 s exposure to the plasma jet, respectively. The bacterial count of wastewater from blackberry and beetroot was reduced by 0.41 and 2.24 log10 colony-forming units (CFU) per ml, respectively, after 180 s. Escherichia coli was the most susceptible bacterial species to the cold plasma while Shigella boydii had the minimum susceptibility, recording 1.30 and 3.34 log10 CFU ml-1, respectively, as compared to the 7.00 log10 initial count. The chemical oxygen demands of wastewater were improved by 57.5-93.3% after 180 s exposure to the plasma jet being tested. The endotoxins in the wastewater were reduced by up to 90.22%. The variation in plasma effectiveness is probably related to the antioxidant concentration of the different investigated wastewaters.

  11. Bacterial Ecology

    DEFF Research Database (Denmark)

    Fenchel, Tom

    2011-01-01

    Bacterial ecology is concerned with the interactions between bacteria and their biological and nonbiological environments and with the role of bacteria in biogeochemical element cycling. Many fundamental properties of bacteria are consequences of their small size. Thus, they can efficiently exploit...

  12. Bacterial meningitis

    NARCIS (Netherlands)

    Heckenberg, Sebastiaan G. B.; Brouwer, Matthijs C.; van de Beek, Diederik

    2014-01-01

    Bacterial meningitis is a neurologic emergency. Vaccination against common pathogens has decreased the burden of disease. Early diagnosis and rapid initiation of empiric antimicrobial and adjunctive therapy are vital. Therapy should be initiated as soon as blood cultures have been obtained,

  13. Bacterial lipases

    NARCIS (Netherlands)

    Jaeger, Karl-Erich; Ransac, Stéphane; Dijkstra, Bauke W.; Colson, Charles; Heuvel, Margreet van; Misset, Onno

    Many different bacterial species produce lipases which hydrolyze esters of glycerol with preferably long-chain fatty acids. They act at the interface generated by a hydrophobic lipid substrate in a hydrophilic aqueous medium. A characteristic property of lipases is called interfacial activation,

  14. Bacterial Ecology

    DEFF Research Database (Denmark)

    Fenchel, Tom

    2011-01-01

    , the production and oxidation of methane, nitrate reduction and fixation of atmospheric nitrogen are exclusively carried out by different groups of bacteria. Some bacterial species – ‘extremophiles’ – thrive in extreme environments in which no eukaryotic organisms can survive with respect to temperature, salinity...

  15. Bacterial Vaginosis

    Science.gov (United States)

    ... that coats the walls of the vagina Vaginal discharge with an unpleasant or fishlike odor Vaginal pain or itching Burning during urination Doctors are unsure of the incubation period for bacterial vaginosis. How Is the Diagnosis Made? Your child’s pediatrician can make the diagnosis ...

  16. Bacterial stress

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. Bacterial stress. Physicochemical and chemical parameters: temperature, pressure, pH, salt concentration, oxygen, irradiation. Nutritional depravation: nutrient starvation, water shortage. Toxic compounds: Antibiotics, heavy metals, toxins, mutagens. Interactions with other cells: ...

  17. Well water quality in rural Nicaragua using a low-cost bacterial test and microbial source tracking.

    Science.gov (United States)

    Weiss, Patricia; Aw, Tiong Gim; Urquhart, Gerald R; Galeano, Miguel Ruiz; Rose, Joan B

    2016-04-01

    Water-related diseases, particularly diarrhea, are major contributors to morbidity and mortality in developing countries. Monitoring water quality on a global scale is crucial to making progress in terms of population health. Traditional analytical methods are difficult to use in many regions of the world in low-resource settings that face severe water quality issues due to the inaccessibility of laboratories. This study aimed to evaluate a new low-cost method (the compartment bag test (CBT)) in rural Nicaragua. The CBT was used to quantify the presence of Escherichia coli in drinking water wells and aimed to determine the source(s) of any microbial contamination. Results indicate that the CBT is a viable method for use in remote rural regions. The overall quality of well water in Pueblo Nuevo, Nicaragua was deemed unsafe, and results led to the conclusion that animal fecal wastes may be one of the leading causes of well contamination. Elevation and depth of wells were not found to impact overall water quality. However rope-pump wells had a 64.1% reduction in contamination when compared with simple wells.

  18. Construction and testing of a bacterial luciferase reporter gene system for in vivo measurement of nonsense suppression in Streptomyces.

    Science.gov (United States)

    Weiser, J; Buriánková, K; Kalachová, L; Branny, P; Pernodet, J L

    2006-01-01

    A reporter gene system, based on luciferase genes from Vibrio harvei, was constructed for measurement of translation nonsense suppression in Streptomyces. Using the site-directed mutagenesis the TCA codon in position 13 of the luxB gene was replaced by all of the three stop codons individually. By cloning of luxA and luxB genes under the control of strong constitutive Streptomyces promoter ermE* in plasmid pUWL201 we created Wluxl with the wild-type sequence and pWlux2, pWlux3 and pWlux4 plasmids containing TGA-, TAG- and TAA-stop codons, respectively. Streptomyces lividans TK 24 was transformed with the plasmids and the reporter system was tested by growth of the strain in the presence of streptomycin as a translation accuracy modulator. Streptomycin increased nonsense suppression on UAA nearly 10-fold and more than 20-fold on UAG. On the other hand, UGA, the most frequent stop signal in Streptomyces, the effect was negligible.

  19. Bacterial Adhesion & Blocking Bacterial Adhesion

    DEFF Research Database (Denmark)

    Vejborg, Rebecca Munk

    2008-01-01

    reduce or delay bacterial biofilm formation of a range of urinary tract infectious E.coli and Klebsiella isolates. Several other proteinaceous coatings were also found to display anti-adhesive properties, possibly providing a measure for controlling the colonization of implant materials. Several other...... components. These substances may both mediate and stabilize the bacterial biofilm. Finally, several adhesive structures were examined, and a novel physiological biofilm phenotype in E.coli biofilms was characterized, namely cell chain formation. The autotransporter protein, antigen 43, was implicated...

  20. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Science.gov (United States)

    2010-07-01

    ... thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens; exemption from the requirement... into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens is...

  1. Low dose endotoxin priming is accountable for coagulation abnormalities and organ damage observed in the Shwartzman reaction. A comparison between a single-dose endotoxemia model and a double-hit endotoxin-induced Shwartzman reaction

    Directory of Open Access Journals (Sweden)

    Cate Hugo

    2006-08-01

    Full Text Available Abstract The clinical response of sepsis to a systemic inflammatory infection may be complicated by disseminated intravascular coagulation or DIC. In order to experimentally study the syndrome of DIC, we aimed for a severe sepsis model complicated by disseminated coagulation. Most -simplified- experimental models describing coagulation abnormalities as a consequence of sepsis are based on single dose endotoxemia. The so called-Shwartzman reaction contrarily, is elicited by a low dose endotoxin priming followed by an LPS challenge and is characterized by pathological manifestations that represent the syndrome of DIC. In order to investigate whether the Shwartzman reaction is superior to a single endotoxin challenge as a model for sepsis-induced DIC and to determine what the pathological effect is of an encounter of low endotoxin prior to an LPS challenge, we undertook the present study. In this study we demonstrate that low-dose endotoxin priming prior to an LPS challenge in the Shwartzman reaction is accountable for micro-vascular thrombosis in lung and liver and subsequent (multi- organ failure, not observed after a single-dose endotoxin challenge, which indicates that the Shwartzman reaction is well suited-model to study sepsis-induced DIC adversities. Remarkably, only minor differences in the innate immune response were established between the single-dose endotoxin challenge and the Shwartzman reaction.

  2. Bacterial meningitis in infants.

    Science.gov (United States)

    Ku, Lawrence C; Boggess, Kim A; Cohen-Wolkowiez, Michael

    2015-03-01

    Neonatal bacterial meningitis is uncommon but devastating. Morbidity among survivors remains high. The types and distribution of pathogens are related to gestational age, postnatal age, and geographic region. Confirming the diagnosis is difficult. Clinical signs are often subtle, lumbar punctures are frequently deferred, and cerebrospinal fluid (CSF) cultures can be compromised by prior antibiotic exposure. Infants with bacterial meningitis can have negative blood cultures and normal CSF parameters. Promising tests such as the polymerase chain reaction require further study. Prompt treatment with antibiotics is essential. Clinical trials investigating a vaccine for preventing neonatal Group B Streptococcus infections are ongoing. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Is the association between pet ownership and indoor endotoxin levels confounded or modified by outdoor residential greenspace?

    Science.gov (United States)

    Fuertes, Elaine; Standl, Marie; Markevych, Iana; Bischof, Wolfgang; Heinrich, Joachim

    2018-06-01

    Pet ownership is consistently associated with higher indoor endotoxin concentrations, but may also be related to the amount of greenspace around the home. This study examined whether the association between pet ownership and higher indoor endotoxin concentrations is confounded or modified by residential greenspace. Information on pet ownership was collected at the time of recruitment of the German LISA birth cohort. Endotoxin levels were measured in settled house dust sampled from mothers' mattresses (N=1197) and living room floors (N=390). Greenspace around the home was assessed as the mean Normalized Difference Vegetation Index in 100m, 500m and 1000m buffers around the home, and as the distance to the nearest urban and natural green space. Linear regression models assessed cross-sectional associations between pet ownership and log-transformed endotoxin levels, adjusted for known predictors of endotoxin levels. Confounding by greenspace was assessed by additionally adjusting the models for each greenspace variable. Effect modification was assessed by including interaction terms between pet ownership and each greenspace variable, and by model stratification. Dog and cat ownership were associated with higher endotoxin levels in mothers' mattresses, whereas only dog ownership was associated with endotoxin levels in the floor samples. All associations were highly robust to further adjustment for greenspace, and there was little evidence to suggest any effect modification (interaction terms had p-values >0.05). Residential greenspace did not confound or modify the association between pet ownership and indoor endotoxin levels. Studies should continue investigating whether pets influence the indoor environment only by their presence, or also by acting as transmission vectors of the outdoors. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Longitudinal distribution of pulmonary vascular resistance after endotoxin administration in sheep.

    Science.gov (United States)

    Pearl, R G; Baer, E R; Siegel, L C; Benson, G V; Rice, S A

    1992-01-01

    Pulmonary hypertension may increase pulmonary capillary pressure and exacerbate pulmonary edema in acute respiratory failure. The effects of pulmonary hypertension on pulmonary capillary pressure depend on the longitudinal distribution of pulmonary vascular resistance. Since pulmonary hypertension occurs during acute respiratory failure, we hypothesized that acute respiratory failure may produce time-dependent changes in the longitudinal distribution of pulmonary vascular resistance. Therefore, we measured pulmonary capillary pressure and the longitudinal distribution of pulmonary vascular resistance in an animal model of acute respiratory failure. Escherichia coli endotoxin (2.5 to 5.0 micrograms/kg) was administered over a 1-hr period in eight anesthetized sheep. Pulmonary and systemic hemodynamics, including pulmonary artery occlusion pressure (PAOP), pulmonary capillary pressure, and the longitudinal distribution of pulmonary vascular resistance, were measured over the next 5 hrs. Pulmonary capillary pressure was estimated by analysis of the pressure decay following pulmonary artery balloon inflation. Endotoxin administration resulted in sustained pulmonary hypertension for the subsequent 5 hrs of the study. Pulmonary capillary pressure was increased 7 mm Hg above baseline at 0.5 and 0.75 hrs during the infusion of endotoxin but returned to baseline values at 1.5 hrs. Despite sustained pulmonary hypertension, pulmonary capillary pressure remained at baseline values for the duration of the study. Similar to pulmonary capillary pressure, pulmonary venous (or postcapillary) resistance was increased approximately four-fold over baseline at 0.5 and 0.75 hrs after initiating endotoxin administration, but returned to baseline values by the end of endotoxin administration and remained at baseline values throughout the remainder of the study. In contrast, pulmonary arterial (or precapillary) resistance remained at values approximately three times baseline during the

  5. Effects of grain, fructose, and histidine feeding on endotoxin and oxidative stress measures in dairy heifers.

    Science.gov (United States)

    Golder, H M; Lean, I J; Rabiee, A R; King, R; Celi, P

    2013-01-01

    Ruminal endotoxin and plasma oxidative stress biomarker concentrations were studied in dairy heifers challenged with grain, fructose, and histidine in a partial factorial study. Holstein-Friesian heifers [n=30; average body weight (BW) of 359.3±47.3 kg] were randomly allocated to 5 treatment groups: (1) control (no grain); (2) grain [crushed triticale at 1.2% of BW dry matter intake (DMI)]; (3) grain (0.8% of BW DMI) + fructose (0.4% of BW DMI); (4) grain (1.2% of BW DMI) + histidine (6g/head); and (5) grain (0.8% of BW DMI) + fructose (0.4% of BW DMI) + histidine (6 g/head). Rumen samples were collected by stomach tube 5, 65, 115, 165, and 215 min after diet consumption and blood samples at 5 and 215 min after consumption. Rumen fluid was analyzed for endotoxin concentrations. Plasma was analyzed for concentrations of the following oxidative stress biomarkers: reactive oxygen metabolites (dROM), biological antioxidant potential (BAP), advanced oxidation protein products, and ceruloplasmin, and activity of glutathione peroxidase. Dietary treatment had no effect on concentrations of endotoxin or oxidative stress biomarkers. We observed no interactions of treatment by time. Ruminal concentrations of endotoxin decreased during the sampling period from 1.12×10(5) ± 0.06 to 0.92×10(5) endotoxin units/mL ± 0.05 (5 and 215 min after diet consumption, respectively). Concentrations of dROM and the oxidative stress index (dROM/BAP × 100) increased over the sampling period, from 108.7 to 123.5 Carratelli units (Carr U), and from 4.1 to 4.8, respectively. Ceruloplasmin concentrations markedly declined 5 min after the consumption of diets, from 190 to 90 mg/L over the 215-min sampling period. Overall, a single feeding challenge for dairy cattle with grain, fructose, and histidine, and combinations thereof, may not be sufficient to induce marked changes in endotoxin or oxidative stress biomarker concentrations. Copyright © 2013 American Dairy Science Association

  6. Occupational exposure to endotoxins and lung cancer risk: results of the ICARE Study.

    Science.gov (United States)

    Ben Khedher, Soumaya; Neri, Monica; Guida, Florence; Matrat, Mireille; Cenée, Sylvie; Sanchez, Marie; Menvielle, Gwenn; Molinié, Florence; Luce, Danièle; Stücker, Isabelle

    2017-09-01

    To investigate the role of occupational exposure to endotoxins in lung cancer in a French population-based case-control study (ICARE (Investigation of occupational and environmental causes of respiratory cancers)). Detailed information was collected on the occupational history and smoking habits from 2926 patients with histologically confirmed lung cancer and 3555 matched controls. We evaluated each subject's endotoxin exposure after cross referencing International Standard Classification of Occupations (ISCO) codes (for job tasks) and Nomenclature d'Activités Françaises (NAF) codes (for activity sectors). Endotoxin exposure levels were attributed to each work environment based on literature reports. ORs and 95% CIs were estimated using unconditional logistic regression models and controlled for main confounding factors. An inverse association between exposure to endotoxins and lung cancer was found (OR=0.80, 95% CI 0.66 to 0.95). Negative trends were shown with duration and cumulative exposure, and the risk was decreased decades after exposure cessation (all statistically significant). Lung cancer risk was particularly reduced among workers highly exposed (eg, in dairy, cattle, poultry, pig farms), but also in those weakly exposed (eg, in waste treatment). Statistically significant interactions were shown with smoking, and never/light smokers were more sensitive to an endotoxin effect than heavy smokers (eg, OR=0.14, 95% CI 0.06 to 0.32 and OR=0.80, 95% CI 0.45 to 1.40, respectively, for the quartiles with the highest cumulative exposure, compared with those never exposed). Pronounced inverse associations were shown with adenocarcinoma histological subtype (OR=0.37, 95% CI 0.25 to 0.55 in the highly exposed). Our findings suggest that exposure to endotoxins, even at a low level, reduces the risk of lung cancer. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is

  7. Bacterial meningitis in children

    International Nuclear Information System (INIS)

    Marji, S.

    2007-01-01

    To demonstrate the epidemiology, clinical manifestations and bacteriological profile of bacterial meningitis in children beyond the neonatal period in our hospital. This was a retrospective descriptive study conducted at Prince Rashid Hospital in Irbid, Jordan. The medical records of 50 children with the diagnosis of bacterial meningitis during 4 years period, were reviewed. The main cause of infection was streptococcus pneumoniae, followed by Haemophilus influenza and Niesseria meningitides. Mortality was higher in infants and meningococcal infection, while complications were more encountered in cases of streptococcus pneumoniae. Cerebrospinal fluid culture was positive in 11 cases and Latex agglutination test in 39. There is a significant reduction of the numbers of bacterial meningitis caused by Haemophilus influenza type B species. (author)

  8. Antibacterial compounds of Canadian honeys target bacterial cell wall inducing phenotype changes, growth inhibition and cell lysis that resemble action of β-lactam antibiotics.

    Science.gov (United States)

    Brudzynski, Katrina; Sjaarda, Calvin

    2014-01-01

    Honeys show a desirable broad spectrum activity against Gram-positive and negative bacteria making antibacterial activity an intrinsic property of honey and a desirable source for new drug development. The cellular targets and underlying mechanism of action of honey antibacterial compounds remain largely unknown. To facilitate the target discovery, we employed a method of phenotypic profiling by directly comparing morphological changes in Escherichia coli induced by honeys to that of ampicillin, the cell wall-active β-lactam of known mechanism of action. Firstly, we demonstrated the purity of tested honeys from potential β-lactam contaminations using quantitative LC-ESI-MS. Exposure of log-phase E. coli to honey or ampicillin resulted in time- and concentration-dependent changes in bacterial cell shape with the appearance of filamentous phenotypes at sub-inhibitory concentrations and spheroplasts at the MBC. Cell wall destruction by both agents, clearly visible on microscopic micrographs, was accompanied by increased permeability of the lipopolysaccharide outer membrane as indicated by fluorescence-activated cell sorting (FACS). More than 90% E. coli exposed to honey or ampicillin became permeable to propidium iodide. Consistently with the FACS results, both honey-treated and ampicillin-treated E. coli cells released lipopolysaccharide endotoxins at comparable levels, which were significantly higher than controls (ptransformed with the ampicillin-resistance gene (β-lactamase) remained sensitive to honey, displayed the same level of cytotoxicity, cell shape changes and endotoxin release as ampicillin-sensitive cells. As expected, β-lactamase protected the host cell from antibacterial action of ampicillin. Thus, both honey and ampicillin induced similar structural changes to the cell wall and LPS and that this ability underlies antibacterial activities of both agents. Since the cell wall is critical for cell growth and survival, honey active compounds would be

  9. Effect of early enteral nutrition (EN) on endotoxin in serum and intestinal permeability in patients with severe acute pancreatitis.

    Science.gov (United States)

    Shen, Q-X; Xu, G-X; Shen, M-H

    2017-06-01

    This work aimed at studying the effect of early enteral nutrition (EN) on serum endotoxin and intestinal permeability in patients with severe acute pancreatitis. 70 cases of patients with severe acute pancreatitis were cured in our hospital from April 2015 to January 2016. Patients selected were randomly divided into two groups including a group of patients having parenteral nutrition (group PN) and that had enteral nutrition (group EN). The results were assessed by: 1) the differences of serum endotoxin level; 2) the differences of the lactulose/mannitol ratio of urine, before intervention and one and two weeks after the intervention. Before the intervention, both groups had similar levels of serum endotoxin and the same lactulose/mannitol excretion rate of urine (p>0.05). One and two weeks after the intervention, the serum endotoxin level and the lactulose/mannitol excretion rate of urine of the group PN were significantly higher than the group EN (pEN has a bigger effect on serum endotoxin and intestinal permeability in patients with severe acute pancreatitis. EN can better promote the elimination of serum endotoxin and reduce intestinal permeability. Therefore, EN deserves clinical expansion.

  10. Risk of lung cancer in relation to contiguous windows of endotoxin exposure among female textile workers in Shanghai

    Science.gov (United States)

    Costello, Sadie; Applebaum, Katie M.; Ray, Roberta M.; Astrakianakis, George; Gao, Dao Li; Thomas, David B.; Checkoway, Harvey; Eisen, Ellen A.

    2012-01-01

    Objective Exposure to endotoxin has been consistently associated with a reduced risk of lung cancer. However, there is a paucity of information regarding temporal aspects of this relationship. The objective of this study was to investigate the associations between contiguous windows of endotoxin exposure and risk of lung cancer. Methods Data were reanalyzed from a case-cohort study (602 cases, 3,038 subcohort) of female textile workers in Shanghai, China. Cumulative endotoxin exposure was partitioned into two windows: ≥20 and windows. Results There was an inverse trend of decreasing risk of lung cancer associated with increasing levels of endotoxin exposure ≥20 years before risk (p trend = 0.02). Women in the highest two categories of cumulative exposures had hazard ratios of 0.78 (95% CI 0.60–1.03) and 0.77 (95% CI 0.58–1.02) for lung cancer, respectively, in comparison with unexposed textile workers. There was, however, a weaker association and not statistically significant between lung cancer and endotoxin exposure accumulated in the more recent window (<20 years before risk). Conclusion Results provide further evidence that endotoxin exposure that occurred 20 years or more before risk confers the strongest protection against lung cancer, indicating a possible early anti-carcinogenic effect. Further studies are needed to better understand the underlying biological mechanisms for this effect. PMID:21732048

  11. Diagnosis of bacterial vaginosis

    Directory of Open Access Journals (Sweden)

    Đukić Slobodanka

    2013-01-01

    Full Text Available Bacterial vaginosis is a common, complex clinical syndrome characterized by alterations in the normal vaginal flora. When symptomatic, it is associated with a malodorous vaginal discharge and on occasion vaginal burning or itching. Under normal conditions, lactobacilli constitute 95% of the bacteria in the vagina. Bacterial vaginosis is associated with severe reduction or absence of the normal H2O2­producing lactobacilli and overgrowth of anaerobic bacteria and Gardnerella vaginalis, Atopobium vaginae, Mycoplasma hominis and Mobiluncus species. Most types of infectious disease are diagnosed by culture, by isolating an antigen or RNA/DNA from the microbe, or by serodiagnosis to determine the presence of antibodies to the microbe. Therefore, demonstration of the presence of an infectious agent is often a necessary criterion for the diagnosis of the disease. This is not the case for bacterial vaginosis, since the ultimate cause of the disease is not yet known. There are a variety of methods for the diagnosis of bacterial vaginosis but no method can at present be regarded as the best. Diagnosing bacterial vaginosis has long been based on the clinical criteria of Amsel, whereby three of four defined criteria must be satisfied. Nugent’s scoring system has been further developed and includes validation of the categories of observable bacteria structures. Up­to­date molecular tests are introduced, and better understanding of vaginal microbiome, a clear definition for bacterial vaginosis, and short­term and long­term fluctuations in vaginal microflora will help to better define molecular tests within the broader clinical context.

  12. IgA against gut-derived endotoxins: does it contribute to suppression of hepatic inflammation in alcohol-induced liver disease?

    DEFF Research Database (Denmark)

    Parlesak, Alexandr; Schäfer, C.; Bode, C.

    2002-01-01

    , endotoxin, and acute-phase proteins were measured in patients with different stages of alcoholic liver disease and in healthy controls. Antibodies of type IgA, but not IgG, against fecal endotoxins were significantly increased in patients with alcohol-induced liver disease. IgA antibodies against fecal......Endotoxins of intestinal origin are supposed to play an important role in the development of alcoholic hepatitis in man. To estimate the role of immunoglobulin response to gut-derived endotoxin in the development of alcohol-induced liver disease, serum levels of IgA and IgG against fecal endotoxin...... endotoxin were found to be closely correlated with the plasma concentrations of alanine aminotransferase, gamma-glutamyl transferase, and C-reactive protein in patients with alcoholic liver disease. In conclusion, as IgA located in body tissue was shown to suppress the inflammatory process, enhanced...

  13. Bacterial lipases

    OpenAIRE

    Jaeger, Karl-Erich; Ransac, Stéphane; Dijkstra, Bauke W.; Colson, Charles; Heuvel, Margreet van; Misset, Onno

    1994-01-01

    Many different bacterial species produce lipases which hydrolyze esters of glycerol with preferably long-chain fatty acids. They act at the interface generated by a hydrophobic lipid substrate in a hydrophilic aqueous medium. A characteristic property of lipases is called interfacial activation, meaning a sharp increase in lipase activity observed when the substrate starts to form an emulsion, thereby presenting to the enzyme an interfacial area. As a consequence, the kinetics of a lipase rea...

  14. Effect of Bacterial Lipopolysaccharide Contamination on Gutta Percha- versus Resilon-Induced Human Monocyte Cell Line Toxicity.

    Directory of Open Access Journals (Sweden)

    Jamshid Hadjati

    2015-04-01

    Full Text Available Cytotoxic effects of obturation materials were tested in presence and absence of endotoxin on human monocytes in vitro.Human monocytes from THP-1 cell line were cultured. Three millimeters from the tip of each Resilon and gutta percha points were cut and directly placed at the bottom of the culture wells. Cultured cells were exposed to gutta percha (groups G1 and G2 and Resilon (R1 and R2. Ten μg/ml bacterial lipopolysaccharide (LPS was added to the culture wells in groups G1 and R1. Positive control included the bacterial LPS without the root canal filling material and the negative control contained the cells in culture medium only. Viability of cells was tested in all groups after 24, 48, and 72 hours using the methylthiazolyldiphenyl-tetrazolium bromide (MTT assay for at least 3 times to obtain reproducible results. Optical density values were read and the data were analyzed using three-way ANOVA and post hoc statistical test.The results showed that cells in G2 had the lowest rate of viability at 24 hours, but the lowest rate of viable cells was recorded in G1 at 48 and 72 hours. The effect of LPS treatment was not statistically significant. Resilon groups showed cell viability values higher than those of gutta percha groups, although statistically non-significant (P=0.105. Cell viability values were lower in gutta percha than Resilon groups when LPS-treated and LPS-untreated groups were compared independently at each time point.It could be concluded that none of the tested root canal filling materials had toxic effects on cultured human monocyte cells whether in presence or absence of LPS contamination.

  15. Immunostimulatory Potential of β-Lactoglobulin Preparations: Effects Caused by Endotoxin Contamination

    DEFF Research Database (Denmark)

    Pedersen, Susanne Brix; Bovetto, L.; Fritsche, R.

    2003-01-01

    previously been shown to mediate cellular activation in both human and murine immune cells.Objective: We examined the response to different beta-lactoglobulin preparations in naive immune cells.Methods: Splenocytes and cells from mesenteric lymph nodes derived from BALB/c mice bred and maintained on a milk......-marrow-derived dendritic cells was examined.Results: We observed that some commercial beta-lactoglobulin preparations induced pronounced proliferation of both spleen cells and cells from mesenteric lymph nodes; production of TNF-alpha, IL-6, IL-1beta, and IL-10; and an increased level of intracellular glutathione...... the immunomodulatory activity. Eventually, the immunostimulatory effect was found to be caused by endotoxin contamination.Conclusion: These results identify endotoxin as the main immunostimulatory component present in some commercial beta-lactoglobulin preparations. Moreover, the present study makes it evident...

  16. Preparation of PVA/amino multi-walled carbon nanotubes nanocomposite microspheres for endotoxin adsorption.

    Science.gov (United States)

    Zong, Wenhui; Chen, Jian; Han, Wenyan; Cheng, Guanghui; Chen, Jie; Wang, Yue; Wang, Weichao; Ou, Lailiang; Yu, Yaoting; Shen, Jie

    2018-02-01

    A novel polyvinyl alcohol-amino multi-walled carbon nanotube (PVA-AMWCNT) nanocomposite microsphere was prepared successfully for the first time and used for endotoxin removal. The resulting AMWCNT modified PVA microsphere was characterized by SEM, Raman spectrum and fluorescence image, which indicated AMWCNT was dispersed into the macropores of PVA microsphere uniformly. The PVA-AMWCNT microspheres showed better adsorption capability and faster adsorption equilibrium for endotoxin in aqueous solution when compared to the PVA microsphere with polymyxin B (PMB) as ligand. More noteworthy, the PVA based microspheres had little nonspecific adsorption in simulated serum. Therefore, PVA-AMWCNT nanocomposite microsphere with an excellent haemocompatibility has a great potential application in clinical blood purification.

  17. Testing Water for Bacterial Pollution.

    Science.gov (United States)

    Dillner, Harry

    This autoinstructional lesson deals with the study of water pollution control. It is a learning activity directed toward high school students of biology and/or ecology. A general knowledge of microbiology techniques is regarded as a prerequisite for the lesson. Behavioral objectives are given. Emphasis is placed on use of techniques and materials…

  18. Structural studies of δ-endotoxin Cry 1 C from Bacillus thuringiensis

    International Nuclear Information System (INIS)

    Guimaraes, B.G.; Garratt, R.C.; Oliva, G.; Lemos, M.V.F.; Arantes, O.M.N.

    1996-01-01

    Full text. The δ-endotoxins are a family of crystal protein by a soil bacterium, Bacillus thuringiensis. The study of these proteins has been of great interest due to their highly specific activity against insects of the orders Lepidoptera, Diptera and Coleoptera. Thus, the δa-endotoxins have been used for more than two decades as biological insecticides to control agricultural pests and, more recently, insects vectors of some diseases. The knowledge of their three-dimensional structures is very important to understand their mechanism of action and their high specificity. To date, the structure of only three proteins of the δ-endotoxins family have been reported: Cry3A, a coleopteran-specific toxin (beetle toxin) 1 , Cry1Aa, a lepidopteran-specific toxin (butterfly toxin) 2 and CytB, a dipteran-specific toxin (mosquito toxin) 3 Our work is aimed at the determination of the crystallographic structure by X-ray diffraction of δ-endotoxin Cry1C, also toxic to insects of the Lepidoptera order but towards families other than those affected by Cry1Aa. A comparison between these structures may lead to important conclusions about the reasons for the specificity and would allow the planning of mutants with more efficient activity. The cry1C gene was cloned into an adequate vector and expressed in an acrystalliferous B. thuringiensis strain. After cell culture and sporulation the microcrystals of Cry1C were separated by ultra-centrifugation in sacharose. The protoxin inclusion bodies were activated by commercial trpsin and the protease-resistant core was purified by anion-exchange chromatography. Crystallization experiments are being conducted in order to obtain single crystals suitable for diffraction measurements. We intend to use the Protein Crystallograph Station of the LNLS to collect data as soon as it is available and we have suitable crystals. (author)

  19. Effect of vasopressors on organ blood flow during endotoxin shock in pigs

    International Nuclear Information System (INIS)

    Breslow, M.J.; Miller, C.F.; Parker, S.D.; Walman, A.T.; Traystman, R.J.

    1987-01-01

    A volume-resuscitated porcine endotoxin shock model was used to evaluate the effect on organ blood flow of increasing systemic arterial blood pressure with vasopressors. Administration of 0.05-0.2 mg/kg of Escherichia coli endotoxin (E) reduced mean arterial blood pressure (MAP) to 50 mmHg, decreased systemic vascular resistance to 50% of control, and did not change cardiac output or heart rate. Blood flow measured with radiolabeled microspheres to brain, kidney, spleen, and skeletal muscle was reduced during endotoxin shock, but blood flow to left ventricle, small and large intestine, and stomach remained at pre-endotoxin levels throughout the study period. Four groups of animals were used to evaluate the effect of vasopressor therapy. Vasopressors were administered starting 60 min after E exposure, and the dose of each was titrated to increase MAP to 75 mmHg. Despite the increase in MAP, brain blood flow did not increase in any group. Norepinephrine alone increased blood flow to the left ventricle. The dose of norepinephrine required to increase MAP by 20-25 mmHg during E shock was 30 times the does required for a similar increase in MAP in animals not receiving E. The authors conclude 1) that hypotension in the fluid resuscitated porcine E shock model is primarily the result of peripheral vasodilatation, 2) that the vascular response to vasoconstrictors in this model is markedly attenuated following E administration, 3) that blood pressure elevation with norepinephrine, dopamine, and phenylephrine neither decreases blood flow to any organs nor increases blood flow to organs with reduced flow, and 4) that norepinephrine, dopamine, and phenylephrine affect regional blood flow similarly in this model

  20. Alterations in hepatic gluconeogenic amino acid uptake and gluconeogenesis in the endotoxin treated conscious dog.

    Science.gov (United States)

    Meinz, H; Lacy, D B; Ejiofor, J; McGuinness, O P

    1998-04-01

    We examined the effect of a 240 min intraportal infusion of a nonlethal dose of Escherichia coli endotoxin (.21 g x kg(-1) x min[-1]) on hepatic amino acid and glucose metabolism in chronically catheterized 42 h fasted conscious dogs (n = 8). Hepatic metabolism was assessed using tracer (3-[3H]glucose [U-14C]alanine) and arteriovenous difference techniques. After endotoxin administration net hepatic glucose output increased twofold. Arterial plasma insulin levels decreased by 25%, whereas arterial plasma glucagon and cortisol levels increased 10- and 6-fold, respectively. Arterial lactate levels increased 6.4-fold, whereas net hepatic lactate uptake was not increased. Arterial alanine levels (1.6-fold) and net hepatic alanine uptake (1.3-fold) increased, whereas net hepatic alanine fractional extraction was unaltered. In contrast, the arterial levels of the other gluconeogenic amino acids (glutamine, glycine, serine, and threonine) decreased. Despite this decrease, net uptake of these amino acids by the liver did not decrease, because net hepatic amino acid fractional extraction increased. Total net hepatic gluconeogenic precursor uptake was unaltered (1.1 +/- .1 to 1.3 +/- .3 mg x kg(-1) x min(-1) expressed in glucose equivalents). In summary, gluconeogenesis does not increase after endotoxin administration. Thus, an increase in net hepatic glycogenolysis accounts for the majority of the increase in hepatic glucose production. The lack of an increase in alanine fractional extraction, despite hyperglucagonemia and a rise in the fractional extraction of other gluconeogenic amino acids, suggests that endotoxin specifically impairs hepatic alanine entry in vivo.

  1. Effects of the immunomodulator, VGX-1027, in endotoxin-induced uveitis in Lewis rats

    DEFF Research Database (Denmark)

    Mangano, K; Sardesai, N Y; Quattrocchi, C

    2008-01-01

    VGX-1027 is a novel, low molecular weight, immunomodulatory compound that has shown efficacy against a variety of immuno-inflammatory disease models in animals including autoimmune diabetes in NOD mice, collagen-induced arthritis and chemically induced inflammatory colitis. Here, we have studied ...... the effects of VGX-1027 on the development of endotoxin-induced uveitis (EIU) in male Lewis rats, as a model of inflammatory ocular diseases in humans....

  2. Expression Profile of Cationic Amino Acid Transporters in Rats with Endotoxin-Induced Uveitis

    OpenAIRE

    Yung-Ray Hsu; Shu-Wen Chang; Chang-Hao Yang; Yi-An Lee; Tzu-Yun Kao

    2016-01-01

    Purpose. The transcellular arginine transportation via cationic amino acid transporter (CAT) is the rate-limiting step in nitric oxide (NO) synthesis, which is crucial in intraocular inflammation. In this study, CAT isoforms and inducible nitric oxide synthase (iNOS) expression was investigated in endotoxin-induced uveitis (EIU). Methods. EIU was induced in Lewis rats by lipopolysaccharide (LPS) injection. In the treatment group, the rats were injected intraperitoneally with the proteasome in...

  3. Management of bacterial kidney disease in Chinook Salmon hatcheries based on broodstock testing by enzyme-linked immunosorbent assay: A multiyear study

    Science.gov (United States)

    Munson, A. Douglas; Elliott, Diane G.; Johnson, Keith

    2010-01-01

    From the mid-1980s through the early 1990s, outbreaks of bacterial kidney disease (BKD) caused by Renibacterium salmoninarum continued in Chinook salmon Oncorhynchus tshawytscha in Idaho Department of Fish and Game (IDFG) hatcheries despite the use of three control methods: (1) injection of returning adult fish with erythromycin to reduce prespawning BKD mortality and limit vertical transmission of R. salmoninarum, (2) topical disinfection of green eggs with iodophor, and (3) prophylactic treatments of juvenile fish with erythromycin-medicated feed. In addition, programs to manage BKD through measurement of R. salmoninarum antigen levels in kidney tissues from spawning female Chinook salmon by an enzyme-linked immunosorbent assay (ELISA) were tested over 13–15 brood years at three IDFG hatcheries. The ELISA results were used for either (1) segregated rearing of progeny from females with high ELISA optical density (OD) values (usually ≥0.25), which are indicative of high R. salmoninarum antigen levels, or (2) culling of eggs from females with high ELISA OD values. The ELISA-based culling program had the most profound positive effects on the study populations. Mortality of juvenile fish during rearing was significantly lower at each hatchery for brood years derived from culling compared with brood years for which culling was not practiced. The prevalence of R. salmoninarum in juvenile fish, as evidenced by detection of the bacterium in kidney smears by the direct fluorescent antibody test, also decreased significantly at each hatchery. In addition, the proportions of returning adult females with kidney ELISA OD values of 0.25 or more decreased 56–85% for fish reared in brood years during which culling was practiced, whereas the proportions of ELISA-negative adults increased 55–58%. This management strategy may allow IDFG Chinook salmon hatcheries to reduce or eliminate prophylactic erythromycin-medicated feed treatments. We recommend using ELISA

  4. The Role of Uncoupling Protein 2 During Myocardial Dysfunction in a Canine Model of Endotoxin Shock.

    Science.gov (United States)

    Wang, Xiaoting; Liu, Dawei; Chai, Wenzhao; Long, Yun; Su, Longxiang; Yang, Rongli

    2015-03-01

    To explore the role of uncoupling protein 2 (UCP2) during myocardial dysfunction in a canine model of endotoxin shock, 26 mongrel canines were randomly divided into the following four groups: A (control group; n = 6), B2 (shock after 2 h; n = 7), B4 (shock after 4 h; n = 7), and B6 (shock after 6 h; n = 6). Escherichia coli endotoxin was injected into the canines via the central vein, and hemodynamics were monitored. Energy metabolism, UCP2 mRNA and protein expression, and UCP2 localization were analyzed, and the correlation between energy metabolism changes, and UCP2 expression was determined. After the canine endotoxin shock model was successfully established, the expression of UCP2 mRNA and protein was found to increase, with later time points showing significant increases (P shock (P shock, and UCP2 may play an important role in this process. The negative correlation between UCP2 expression and energy metabolism requires further study, as the results might contribute to the treatment of sepsis with heart failure.

  5. Treatment of sepsis by extracorporeal elimination of endotoxin using polymyxin B-immobilized fiber.

    Science.gov (United States)

    Aoki, H; Kodama, M; Tani, T; Hanasawa, K

    1994-04-01

    Despite the use of potent antibiotics and intensive supportive care, mortality remains high among septic shock patients, especially those with endotoxemia. To remove endotoxin directly from the blood, a material consisting of polymyxin B that is immobilized on fibers (PMX-F) and that can selectively detoxify endotoxin was developed. In a preliminary clinical study, 16 patients with septic multiple organ failure were treated with direct hemoperfusion using a PMX-F column. This therapy significantly decreased the endotoxin level from 76 pg/mL to 21 pg/mL after 2 hours of direct hemoperfusion. The hyperdynamic state of the cardiac index, which is a characteristic of endotoxic shock, returned to normal levels after treatment. In septic shock patients with a systolic pressure of less than 100 mm Hg, the systolic arterial pressure increased significantly from the pretreatment level. The alleviation of fever caused by this therapy continued until the day after treatment. Of the 16 patients who underwent this therapy, 9 were alive 2 weeks after this therapy and 7 patients were discharged from the hospital alive. Hemoperfusion with PMX may be an effective treatment for sepsis and septic shock.

  6. Mitochondrial DAMPs induce endotoxin tolerance in human monocytes: an observation in patients with myocardial infarction.

    Directory of Open Access Journals (Sweden)

    Irene Fernández-Ruiz

    Full Text Available Monocyte exposure to mitochondrial Danger Associated Molecular Patterns (DAMPs, including mitochondrial DNA (mtDNA, induces a transient state in which these cells are refractory to further endotoxin stimulation. In this context, IRAK-M up-regulation and impaired p65 activity were observed. This phenomenon, termed endotoxin tolerance (ET, is characterized by decreased production of cytokines in response to the pro-inflammatory stimulus. We also show that monocytes isolated from patients with myocardial infarction (MI exhibited high levels of circulating mtDNA, which correlated with ET status. Moreover, a significant incidence of infection was observed in those patients with a strong tolerant phenotype. The present data extend our current understanding of the implications of endotoxin tolerance. Furthermore, our data suggest that the levels of mitochondrial antigens in plasma, such as plasma mtDNA, should be useful as a marker of increased risk of susceptibility to nosocomial infections in MI and in other pathologies involving tissue damage.

  7. Endotoxin levels correlate positively with a sedentary lifestyle and negatively with highly trained subjects

    Directory of Open Access Journals (Sweden)

    Oyama Lila M

    2010-08-01

    Full Text Available Abstract Introduction A sedentary lifestyle increases the risk of developing cardiovascular disease, obesity, and diabetes. This phenomenon is supported by recent studies suggesting a chronic, low-grade inflammation status. Endotoxin derived from gut flora may be key to the development of inflammation by stimulating the secretion of inflammatory factors. This study aimed to examine plasma inflammatory markers and endotoxin levels in individuals with a sedentary lifestyle and/or in highly trained subjects at rest. Methods: Fourteen male subjects (sedentary lifestyle n = 7; highly trained subjects n = 7 were recruited. Blood samples were collected after an overnight fast (~12 h. The plasmatic endotoxin, plasminogen activator inhibitor type-1 (PAI-1, monocyte chemotactic protein-1 (MCP1, ICAM/CD54, VCAM/CD106 and lipid profile levels were determined. Results Endotoxinemia was lower in the highly trained subject group relative to the sedentary subjects (p Conclusion These results indicate that a lifestyle associated with high-intensity and high-volume exercise induces favorable changes in chronic low-grade inflammation markers and may reduce the risk for diseases such as obesity, diabetes and cardiovascular diseases.

  8. Effect of inhaled endotoxin on mucociliary clearance and airway inflammation in mild smokers and nonsmokers.

    Science.gov (United States)

    Bennett, William D; Alexis, Neil E; Almond, Martha; Herbst, Margaret; Zeman, Kirby L; Peden, David B

    2014-12-01

    In healthy nonsmokers, inhaled endotoxin [lipopolysaccharide (LPS)] challenge induces airway neutrophilia and modifies innate immune responses, but the effect on mucociliary clearance (MCC), a key host defense response, is unknown. Although smokers are chronically exposed to LPS through inhaled tobacco smoke, the acute effect of inhaled LPS on both MCC and airway inflammation is also unknown. The purpose of this study was to determine the effect of inhaled LPS on MCC in nonsmokers and mild smokers with normal pulmonary function. We performed an open-label inhalational challenge with 20,000 endotoxin units in healthy adult nonsmokers (n=18) and young adult, mild smokers (n=12). At 4 hr post LPS challenge, we measured MCC over a period of 2 hr, followed by sputum induction to assess markers of airway inflammation. No significant changes in spirometry occurred in either group following LPS challenge. Following LPS, MCC was significantly (psmokers [MCC=10±9% (challenge) vs. 15±8% (baseline), MCC=14±9% (challenge) vs. 16±10% (baseline), respectively]. Both groups showed a significant (psmokers is unaffected by mild endotoxin challenge, likely due to preexisting effects of cigarette smoke on their airway epithelium.

  9. Ceftaroline activity tested against bacterial isolates from pediatric patients: results from the assessing worldwide antimicrobial resistance and evaluation program for the United States (2011-2012).

    Science.gov (United States)

    Sader, Helio S; Mendes, Rodrigo E; Farrell, David J; Flamm, Robert K; Jones, Ronald N

    2014-08-01

    Ceftaroline, the active form of ceftaroline fosamil, is a cephalosporin with broad-spectrum bactericidal activity against resistant Gram-positive organisms, including methicillin-resistant Staphylococcus aureus, ceftriaxone-resistant Streptococcus pneumoniae and many Enterobacteriaceae species. Ceftaroline fosamil is approved in the United States for treatment of acute bacterial skin and skin structure infections and community-acquired bacterial pneumonia in adults. A total of 5291 consecutive unique pediatric patient strains of clinical significance were collected from 157 US medical centers. The isolates were identified locally and forwarded to a central monitoring laboratory for reference antimicrobial susceptibility testing. S. pneumoniae isolates from the 2011 to 2012 respiratory season were serotyped. Susceptibility results were analyzed according to patient age as follows: ≤ 1 years old (yo; 1857 strains); 2-5 (1342); 6-12 (1281) and 13-17 (811). Methicillin-resistant Staphylococcus aureus rates were slightly lower in isolates from patients 13-17 yo (39.9%) compared with other age groups (48.2-51.5%), and ceftaroline was consistently active against S. aureus isolates from all 4 age groups [minimal inhibitory concentration (MIC50/90): 0.25-05/1 μg/mL; 99.8-100.0% susceptible]. Overall, 99.8% of methicillin-resistant Staphylococcus aureus were ceftaroline susceptible (MIC50/90: 0.5/1 μg/mL). All S. pneumoniae strains (1178) were ceftaroline susceptible (MIC50/90: ≤ 0.015/0.12 μg/mL), whereas ceftriaxone susceptibility varied from only 84.8 (≤ 1 yo) to 89.7% (13-17 yo). 19A was the most frequent serotype identified among S. pneumoniae and these isolates exhibited low susceptibility to ceftriaxone (42.4%) and most other antimicrobials tested. The highest ceftaroline MIC among Haemophilus influenzae (587 strains) was 0.12 μg/mL (100.0% susceptible), and β-lactamase production rates varied from 24.2 (13-17 yo) to 30.1% (6-12 yo); 27.9% overall

  10. Bacterial mitosis

    DEFF Research Database (Denmark)

    Møller-Jensen, Jakob; Borch, Jonas; Dam, Mette

    2003-01-01

    Bacterial DNA segregation takes place in an active and ordered fashion. In the case of Escherichia coli plasmid R1, the partitioning system (par) separates paired plasmid copies and moves them to opposite cell poles. Here we address the mechanism by which the three components of the R1 par system...... movement is powered by insertional polymerization of ParM. Consistently, we find that segregating plasmids are positioned at the ends of extending ParM filaments. Thus, the process of R1 plasmid segregation in E. coli appears to be mechanistically analogous to the actin-based motility operating...

  11. Cigarette Smoke Exposure Worsens Endotoxin-Induced Lung Injury and Pulmonary Edema in Mice.

    Science.gov (United States)

    Gotts, Jeffrey E; Abbott, Jason; Fang, Xiaohui; Yanagisawa, Haru; Takasaka, Naoki; Nishimura, Stephen L; Calfee, Carolyn S; Matthay, Michael A

    2017-09-01

    Cigarette smoking (CS) remains a major public health concern and has recently been associated with an increased risk of developing acute respiratory distress syndrome (ARDS). Bronchoalveolar lavage (BAL) experiments in human volunteers have demonstrated that active smokers develop increased alveolar-epithelial barrier permeability to protein after inhaling lipopolysaccharide (LPS). Here we tested the hypothesis that short-term whole-body CS exposure would increase LPS-induced lung edema in mice. Adult mice were exposed in a Teague TE-10 machine to CS from 3R4F cigarettes at 100 mg/m3 total suspended particulates for 12 days, then given LPS or saline intratracheally. Control mice were housed in the same room without CS exposure. Post-mortem measurements included gravimetric lung water and BAL protein, cell counts, and lung histology. Cytokines were measured in lung homogenate by ELISA and in plasma by Luminex and ELISA. In CS-exposed mice, intratracheal LPS caused greater increases in pulmonary edema by gravimetric measurement and histologic scoring. CS-exposed mice also had an increase in BAL neutrophilia, lung IL-6, and plasma CXCL9, a T-cell chemoattractant. Intratracheal LPS concentrated blood hemoglobin to a greater degree in CS-exposed mice, consistent with an increase in systemic vascular permeability. These results demonstrate that CS exposure in endotoxin injured mice increases the severity of acute lung injury. The increased lung IL-6 in CS-exposed LPS-injured mice indicates that this potent cytokine, previously shown to predict mortality in patients with ARDS, may play a role in exacerbating lung injury in smokers and may have utility as a biomarker of tobacco-related lung injury. Our results suggest that short-term CS exposure at levels that cause no overt lung injury may still prime the lung for acute inflammatory damage from a "second hit", a finding that mirrors the increased risk of developing ARDS in patients who smoke. This model may be useful for

  12. Endotoxin-induced and vaccine-induced systemic inflammation both impair endothelium-dependent vasodilation, but not pulse wave reflection

    Directory of Open Access Journals (Sweden)

    Lind L

    2012-07-01

    Full Text Available Lars Lind,1 Johannes Hulthe,2,3 Annika Johansson,3 Ewa Hedner31Department of Medicine, University Hospital, Uppsala, 2Sahlgrenska Hospital, Gothenburg, 3AstraZeneca Research and Development, Mölndal, SwedenBackground: Inflammation induced by either endotoxin or vaccination has previously been shown to impair endothelium-dependent vasodilation (EDV in healthy young individuals. However, the vascular effects of these two mechanisms of inducing inflammation have not been compared in the same individuals.Methods: Twelve young healthy males were studied at the same time of the day on three occasions in a random order; on one occasion 4 hours following an endotoxin injection (Escherichia coli endotoxin, 20 IU/kg, on another occasion 8 hours following vaccination against Salmonella typhi, and on a third occasion 4 hours following a saline control injection. EDV and endothelium-independent vasodilation (EIDV were evaluated by local infusions of acetylcholine and sodium nitroprusside in the brachial artery, and forearm blood flow was measured with venous occlusion plethysmography. The augmentation index was determined by pulse wave analysis as an index of pulse wave reflection.Results: Both endotoxin and vaccination impaired EDV to a similar degree compared with the saline control (P = 0.005 and P = 0.014, respectively. EIDV was not significantly affected by inflammation. Endotoxin, but not vaccination, increased body temperature and circulating levels of intracellular adhesion molecule-1 and interleukin-6. Augmentation index was not affected by the interventions.Conclusion: Despite the fact that endotoxin induced a more pronounced degree of inflammation than vaccination, both inflammatory challenges impaired EDV to a similar degree, supporting the view that different inflammatory stimuli could induce harmful effects on the vasculature.Keywords: endothelium, endotoxin, vaccination, vasodilation, inflammation

  13. Macrophage subset sensitivity to endotoxin tolerisation by Porphyromonas gingivalis.

    Directory of Open Access Journals (Sweden)

    Andrew D Foey

    Full Text Available Macrophages (MΦs determine oral mucosal responses; mediating tolerance to commensal microbes and food whilst maintaining the capacity to activate immune defences to pathogens. MΦ responses are determined by both differentiation and activation stimuli, giving rise to two distinct subsets; pro-inflammatory M1- and anti-inflammatory/regulatory M2- MΦs. M2-like subsets predominate tolerance induction whereas M1 MΦs predominate in inflammatory pathologies, mediating destructive inflammatory mechanisms, such as those in chronic P.gingivalis (PG periodontal infection. MΦ responses can be suppressed to benefit either the host or the pathogen. Chronic stimulation by bacterial pathogen associated molecular patterns (PAMPs, such as LPS, is well established to induce tolerance. The aim of this study was to investigate the susceptibility of MΦ subsets to suppression by P. gingivalis. CD14(hi and CD14(lo M1- and M2-like MΦs were generated in vitro from the THP-1 monocyte cell line by differentiation with PMA and vitamin D3, respectively. MΦ subsets were pre-treated with heat-killed PG (HKPG and PG-LPS prior to stimulation by bacterial PAMPs. Modulation of inflammation was measured by TNFα, IL-1β, IL-6, IL-10 ELISA and NFκB activation by reporter gene assay. HKPG and PG-LPS differentially suppress PAMP-induced TNFα, IL-6 and IL-10 but fail to suppress IL-1β expression in M1 and M2 MΦs. In addition, P.gingivalis suppressed NFκB activation in CD14(lo and CD14(hi M2 regulatory MΦs and CD14(lo M1 MΦs whereas CD14(hi M1 pro-inflammatory MΦs were refractory to suppression. In conclusion, P.gingivalis selectively tolerises regulatory M2 MΦs with little effect on pro-inflammatory CD14(hi M1 MΦs; differential suppression facilitating immunopathology at the expense of immunity.

  14. Encapsulated Bifidobacteria reduced bacterial translocation in rats following hemorrhagic shock and resuscitation.

    Science.gov (United States)

    Ruan, Xiangcai; Shi, Hanping; Xia, Gengfeng; Xiao, Ying; Dong, Jiaxi; Ming, Feiping; Wang, Shenming

    2007-10-01

    The aim of the present study was to determine the effects of peroral encapsulated Bifidobacteria on intestinal microflora, bacterial translocation (BT), plasma endotoxin, and ileal villi injury in a rat model of hemorrhagic shock. Sprague-Dawley rats were fed daily with three different diet supplements: phosphate buffered saline, Bifidobacteria (10(9) colon-forming units/day), or microencapsulated Bifidobacteria (10(9) colony-forming units/day). After 7 d of treatment, rats were anesthetized for hemorrhagic or sham shock. Then a laparotomy was performed to determine microbiological analysis of cecal content, BT to mesenteric lymph nodes, plasma endotoxin, and terminal ileal villous damage. In the hemorrhagic-shock model, rats pretreated with Bifidobacteria showed decreases in total aerobes in cecum, magnitude of total aerobes to BT, levels of plasma endotoxin, and percentage of ileal villous damage when compared with rats treated with phosphate buffered saline. Encapsulated Bifidobacteria induced greater decreases than intact Bifidobacteria in this model, except for no difference in percentage of ileal villous damage between the two groups. In addition, the incidence of BT was decreased in hemorrhagic rats pretreated with Bifidobacteria compared with control. However, the magnitude of total anaerobes and Bifidobacteria BT were similar among hemorrhagic-shocked rats receiving three different supplements. Bifidobacteria can be useful in preventing BT in hemorrhagic-shocked rats, and encapsulated Bifidobacteria can augment this effect further. Peroral administration of Bifidobacteria may be a favorable strategy to prevent sepsis and multiple organ dysfunction syndrome in hemorrhagic shock.

  15. Sensitive measurement of endotoxin by radio-rocket immunoelectrophoresis using [125I]Staphylococcus aureus protein A

    International Nuclear Information System (INIS)

    Stevens, P.; Alam, S.; Young, L.S.; Chesebro, K.

    1981-01-01

    Antibody directed against the core glycolipid antigen (CGL) of the mutant Salmonella minnesota Re 595 has been shown to cross-react with endotoxin from bacteria within the group Enterobacteriaceae. Using this cross-reactive CGL antibody the authors have developed a sensitive (250 pg) radio-rocket immunoelectrophoretic technique to measure endotoxin. They used the principles of rocket immunoelectrophoresis and increased the sensitivity by using 125 I-labelled staphylococcal protein A which serves as a sensitive probe to bind to the Fc portion of the IgG complexed with antigen. The rocket-shaped [ 125 I]protein A labelled immune complexes were detected by radioautography. The sensitivity is 100-fold greater than conventional Coomassie brilliant blue staining. Measurement of CGL was inhibited by normal human serum. However, the assay had the capacity to quantitate endotoxin in buffer extracts of clinically isolated Escherichia coli, Serratia marcescens, Klebsiella pneumoniae but not Pseudomonas aeruginosa. Analysis of various preparations of CGL obtained from different investigators demonstrated wide variation in their immunoreactivity. Because of the significant cross-reaction to detect various endotoxins this method has the potential to measure endotoxemia and assess the immunochemical quality of various endotoxin preparations. Additionally, the techniques of using [ 125 I]protein A has wide applicability for the sensitive measurement of other antigens. (Auth.)

  16. C-reactive protein and bacterial meningitis

    DEFF Research Database (Denmark)

    Gerdes, Lars Ulrik; Jørgensen, P E; Nexø, E

    1998-01-01

    The aim of the study was to review published articles on the diagnostic accuracy of C-reactive protein (CRP) tests with cerebrospinal fluid and serum in diagnosing bacterial meningitis. The literature from 1980 and onwards was searched using the electronic databases of MEDLINE, and we used summary...... measured in serum, and 4 in which it had been measured in both cerebrospinal fluid and serum. The odds ratio for bacterial meningitis versus aseptic meningitis for a positive CRP test with cerebrospinal fluid was estimated at 241 (95% confidence interval [CI]: 59-980), and the central tendencies.......06-0.08, respectively, the post-test probability of not having bacterial meningitis given a negative test is very high (> or = 97%), in the range of a pre-test probability (prevalence of bacterial meningitis) from 10 to 30%, whereas the post-test probability of bacterial meningitis given a positive test is considerably...

  17. [Bacterial biofilms on PVC tubing's inner surface of hemodialysis water treatment system].

    Science.gov (United States)

    Yang, Sha; Jia, Ke; Peng, Youming; Liu, Hong; Liu, Yinghong; Chen, Xing; Liu, Fuyou

    2009-10-01

    To determine the morphology, bacteria and endotoxin content of biofilms on the inner surface of PVC tubes in hemodialysis water treatment system. We dissolved biofilms of segments before and after reverse osmosis machine for bacterial count and identification. We studied biofilm structure of segments before and after reverse osmosis machine with eyes and scanning electron microscope. Biofilms of all 7 segments were dissolved for qualitative and quantitative assay of endotoxin. The inner surface of segment before reverse osmosis machine was homogeneously distributed with activated carbon powder deposition. The segment after reverse osmosis machine was normal. With scanning electron microscope, biofilm with successive surface and sandwich was found on the inner surface of segment before reverse osmosis machine, formed by clustering bacillus, activated carbon powder and some coccus. Bacteria of the same shape and length were found on segment after reverse osmosis machine, but fewer and looser. Bacterial culture and identification showed the former was mostly gram-negative bacillus, the latter was only a few micrococcus. Endotoxin of biofilm was between 2.0 EU/mL and 4.0 EU/mL. Quantitative assay showed: segment after softener (2.821+/-0.807) EU/mL; segment after active charcoal canister(3.635+/-0.427) EU/mL; segment before reverse osmosis machine (3.687+/-0.271) EU/mL; segment after reverse osmosis machine (2.041+/-0.295) EU/mL; exit of power pump (1.983+/-0.390)EU/mL;the 1st dead space (2.373+/-0.535) EU/mL; and the 2nd dead space (2.858+/-0.690)EU/mL. Biofilms are found on the inner surface of segment before and after reverse osmosis machine. Endotoxin level from high to low is as follows: segment before reverse osmosis machine, segment after active charcoal canister, the 2nd dead space, segment after softener, the 1st dead space, segment after reverse osmosis machine, exit of power pump. The character of the bacteria and endotoxin of the biofilm can help us find

  18. Seasonal Changes in Endotoxin Exposure and Its Relationship to Exhaled Nitric Oxide and Exhaled Breath Condensate pH Levels in Atopic and Healthy Children.

    Science.gov (United States)

    Wan, Gwo-Hwa; Yan, Dah-Chin; Tung, Tao-Hsin; Tang, Chin-Sheng; Liu, Chiu-Hsin

    2013-01-01

    Endotoxin, a component of the cell walls of gram-negative bacteria, is a contaminant in organic dusts (house dust) and aerosols. In humans, small amounts of endotoxin may cause a local inflammatory response. Exhaled nitric oxide (eNO) levels, an inflammation indicator, are associated with the pH values of exhaled breath condensate (EBC). This study evaluated seasonal changes on indoor endotoxin concentrations in homes and the relationships between endotoxin exposure and eNO/EBC pH levels for healthy children and children with allergy-related respiratory diseases. In total, 34 children with allergy-related respiratory diseases and 24 healthy children were enrolled. Indoor air quality measurements and dust sample analysis for endotoxin were conducted once each season inside 58 surveyed homes. The eNO, EBC pH levels, and pulmonary function of the children were also determined. The highest endotoxin concentrations were on kitchen floors of homes of children with allergy-related respiratory diseases and healthy children, and on bedroom floors of homes of asthmatic children and healthy children. Seasonal changes existed in endotoxin concentrations in dust samples from homes of children with allergic rhinitis, with or without asthma, and in EBC pH values among healthy children and those with allergy-related respiratory diseases. Strong relationships existed between endotoxin exposure and EBC pH values in children with allergic rhinitis.

  19. Nutrition, microbiota, and endotoxin-related diseases in dairy cows Nutrição, microbiota e doenças relacionadas à endotoxina em vacas leiteiras

    Directory of Open Access Journals (Sweden)

    Burim N. Ametaj

    2010-07-01

    Full Text Available In this review article we present an overall summary of the role that high-grain/low forage diets have on rumen composition of microbiota and how changes in the diet affect the release of bacterial cell wall components that are toxic to the host. One of these toxic compounds is lipopolysaccharide or endotoxin, a component of the outer membrane of all Gram-negative bacteria. Moreover, data are provided that support the concept that endotoxin translocates into the blood circulation and show that rumen endotoxin is associated with multiple perturbations of blood variables related to carbohydrate, lipid, and mineral metabolism. In addition, endotoxin induces a general, nonspecific immune response known as acute phase response. We also pinpoint the fact that high-grain diets are associated with distinct clusters of plasma metabolites and immune variables suggesting that changing cereal grain to forage ratio in the diet is very important for the health of dairy cattle. Furthermore, we provide information that support the concept that endotoxin is involved in multiple metabolic diseases such as fatty liver, milk fever, laminitis, retained placenta, displaced abomasum, and downer cow syndrome. More research is warranted to clarify the mechanisms by which nutrition, microbiota, and endotoxin contribute to development of metabolic diseases in dairy cattle. It is concluded that besides the aforementioned causal agents other compounds generated in the gastrointestinal tract such as lipoteichoic acid or methylated amines might be involved in the etiology of several metabolic diseases.Neste artigo de revisão é apresentado um resumo total do papel que a dieta de alto teor de grãos e baixo teor de forragem tem sobre a composição da microbiota do rúmen e como as mudanças na dieta afetam a liberação de componentes da parede celular bacteriana tóxicos ao hospedeiro. Um destes compostos tóxicos é um lipopolisacarídeo ou endotoxina, um componente da

  20. The unique role of dietary L-arginine in the acceleration of peritoneal macrophage sensitivity to bacterial endotoxin

    Czech Academy of Sciences Publication Activity Database

    Pekarová, Michaela; Kubala, Lukáš; Papežíková, Ivana; Králová, Stanislava; Baldus, S.; Klinke, A.; Kuchta, R.; Kadlec, J.; Kuchtová, Z.; Kolářová, Hana; Lojek, Antonín

    2013-01-01

    Roč. 56, č. 1 (2013), s. 73-84 ISSN 0257-277X R&D Projects: GA ČR(CZ) GA524/08/1753 Institutional research plan: CEZ:AV0Z50040702 Institutional support: RVO:68081707 Keywords : NITRIC-OXIDE-SYNTHASE * SUPEROXIDE ANION PRODUCTION * AMINO-ACID TRANSPORTERS Subject RIV: BO - Biophysics Impact factor: 3.525, year: 2013

  1. Evaluation of a nested PCR test and bacterial culture of swabs from the nasal passages and from abscesses in relation to diagnosis of Streptococcus equi infection (strangles)

    DEFF Research Database (Denmark)

    Grønbæk, L.M.; Angen, Øystein; Vigre, Håkan

    2006-01-01

    Reasons for performing study: Streptococcus equi is the cause of strangles in horses. To improve diagnostic sensitivity, development and evaluation of DNA-based methods are necessary. Objectives: To evaluate diagnostic methods and observe the pattern of bacterial shedding during natural outbreaks...... and specificity without the potential problems inherent in nested PCR....

  2. Effect of Endotoxin from Serratia marcescens on the Permeability of Vessels in Hepatomas and Carrageenin Granulomas of Rats

    Science.gov (United States)

    Oswald, N. T. A.; Cater, D. B.

    1969-01-01

    Serratia marcescens polysaccharide (endotoxin) was injected i.v. into rats bearing carrageenin-induced granulomas and transplanted hepatomas, and the vascular-permeability changes were studied by injecting Pelikan ink i.v. at various times after the endotoxin (or saline in the controls). When the ink was given at 0 or 1 hr. there was little difference between the treated rats and the controls. But when the ink was given 2 or more hr. after the endotoxin there was a marked increase of the carbon-lined capillaries and venules, compared with controls, in tumour, granuloma, glomeruli, adrenal cortex, lung, lymph-nodes and sometimes heart. The significance of these changes is discussed in relation to the Shwartzman phenomenon, Arthus reaction, and adrenaline-induced vascular spasm producing anoxia. ImagesFigs. 2-5Figs. 6-9 PMID:4304259

  3. Host defense peptides of thrombin modulate inflammation and coagulation in endotoxin-mediated shock and Pseudomonas aeruginosa sepsis

    DEFF Research Database (Denmark)

    Kalle, Martina; Papareddy, Praveen; Kasetty, Gopinath

    2012-01-01

    Gram-negative sepsis is accompanied by a disproportionate innate immune response and excessive coagulation mainly induced by endotoxins released from bacteria. Due to rising antibiotic resistance and current lack of other effective treatments there is an urgent need for new therapies. We here...... present a new treatment concept for sepsis and endotoxin-mediated shock, based on host defense peptides from the C-terminal part of human thrombin, found to have a broad and inhibitory effect on multiple sepsis pathologies. Thus, the peptides abrogate pro-inflammatory cytokine responses to endotoxin...... sepsis, the peptide GKY25, while mediating a modest antimicrobial effect, significantly inhibited the pro-inflammatory response, decreased fibrin deposition and leakage in the lungs, as well as reduced mortality. Taken together, the capacity of such thrombin-derived peptides to simultaneously modulate...

  4. Treatment of rat Walker-256 carcinosarcoma with photodynamic therapy and endotoxin irradiated with high-energy electrons

    Science.gov (United States)

    Dima, Vasile F.; Vasiliu, Virgil V.; Laky, Dezideriu; Ionescu, Mircea D.; Dima, Stefan V.

    1994-03-01

    Experiments were performed on five batches of Wistar inbred rats with Walker-256 carcinosarcoma receiving sole treatment photodynamic therapy (PDT), irradiated endotoxin (R-LPS), native-endotoxin (N-LPS), or associated therapy (PDT + R-LPS) and the control batch (saline) consisted of animals with untreated Walker-256 tumors. The results were as follows: the sole treatment (PDT, R-LPS, N-LPS) gave survival rates between 56.3 and 60.7% and cure rates ranging from 32.1 to 37.5%. The `combined' therapy in multiple doses increased significantly (88.6%) the survival rate of tumor bearing rats as well as the highest incidence of complete tumor regression (71.4%). This work demonstrates that `combined' photodynamic and immunotherapy with irradiated endotoxin stimulates cell-mediated antitumoral activity and induces changes in the tumoral incidence in Walker-256 carcinosarcoma in the rat model.

  5. The cardiocirculatory and metabolic effects of endotoxin challenge after canine resuscitated hemorrhagic shock.

    Science.gov (United States)

    Horton, J

    1989-02-01

    Although adequate volume resuscitation has decreased mortality from hemorrhagic shock, recovery in many patients is complicated by sepsis. To determine whether a subject debilitated by hemorrhagic shock would exhibit greater cardiocirculatory dysfunction when challenged with sepsis, ten dogs (Group I) were hemorrhaged to a mean arterial blood pressure of 30 mm Hg. After 2 hours of hypotension, shed blood and lactated Ringer's solution (50 ml/kg) were given, and the dogs were observed for 3 to 6 days. Ten dogs were sham hemorrhage and served as controls (Group II). On the experimental day, all cardiovascular and hemodynamic parameters were measured in both groups of animals before endotoxin challenge. There was no significant difference in cardiac output, stroke volume, stroke work, +dP/dt max, myocardial blood flow, myocardial oxygen metabolism, or acid-base balance in the two groups. Compared to sham-hemorrhaged dogs, resuscitated shock dogs had a significantly lower mean arterial blood pressure (127 +/- 7 vs. 110 +/- 6 mm Hg; p less than 0.05), and heart rate was significantly higher (86 +/- 6 vs. 109 +/- 7 beats/minute; p less than 0.05). Furthermore, maximal rate of left ventricular pressure fall (-dP/dT max) was significantly lower in the animals previously hemorrhaged, suggesting a persistent defect in left ventricular relaxation. Blood glucose and insulin levels were significantly elevated in the resuscitated shocked dogs, likely due to increased circulating catecholamine concentrations and enhanced glycogenolysis. Endotoxin shock caused significant hypotension, acidosis, and impaired regional perfusion in all dogs. In addition, cardiac output, stroke volume, dP/dT, and left ventricular end-diastolic pressure fell and hyperglycemia and hyperinsulinemia occurred in all dogs after endotoxin injection.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. BACTERIAL PLASMIDS

    Directory of Open Access Journals (Sweden)

    Marina Dinic

    2007-12-01

    Full Text Available Plasmids, extrachromosomal DNA, were identified in bacteria pertaining to family of Enterobacteriacae for the very first time. After that, they were discovered in almost every single observed strain. The structure of plasmids is made of circular double chain DNA molecules which are replicated autonomously in a host cell. Their length may vary from few up to several hundred kilobase (kb. Among the bacteria, plasmids are mostly transferred horizontally by conjugation process. Plasmid replication process can be divided into three stages: initiation, elongation, and termination. The process involves DNA helicase I, DNA gyrase, DNA polymerase III, endonuclease, and ligase.Plasmids contain genes essential for plasmid function and their preservation in a host cell (the beginning and the control of replication. Some of them possess genes whichcontrol plasmid stability. There is a common opinion that plasmids are unnecessary fora growth of bacterial population and their vital functions; thus, in many cases they can be taken up or kicked out with no lethal effects to a plasmid host cell. However,there are numerous biological functions of bacteria related to plasmids. Plasmids identification and classification are based upon their genetic features which are presented permanently in all of them, and these are: abilities to preserve themselves in a host cell and to control a replication process. In this way, plasmids classification among incompatibility groups is performed. The method of replicon typing, which is based on genotype and not on phenotype characteristics, has the same results as in compatibility grouping.

  7. Phosphatidylcholine Reverses Ethanol-Induced Increase in Transepithelial Endotoxin Permeability and Abolishes Transepithelial Leukocyte Activation

    DEFF Research Database (Denmark)

    Mitzscherling, Katja; Volynets, Valentina; Parlesak, Alexandr

    2009-01-01

    activation of human leukocytes. For this purpose, we used a model in which intestinal epithelial cells (Caco-2) were basolaterally cocultivated with mononuclear leukocytes. Cells were challenged apically with endotoxin from Escherichia coli K12 and were incubated with or without the addition of CPBS (1.5 m...... of leukocytes were nearly completely abolished after the apical supplementation of PC with CPBS, but not by CPBS alone. Ethanol up to 66 mM was not able to reverse this effect. A considerable part of the therapeutic and preventive effect of PC supplementation in ALD might result from a reduction of ethanol...

  8. Exposure to airborne microorganisms, dust and endotoxin during processing of peppermint and chamomile herbs on farms.

    Science.gov (United States)

    Skórska, Czesława; Sitkowska, Jolanta; Krysińska-Traczyk, Ewa; Cholewa, Grazyna; Dutkiewicz, Jacek

    2005-01-01

    The aim of this study was to determine the levels of microorganisms, dust and endotoxin in the air during processing of peppermint (Mentha piperita) and chamomile (Matricaria recutita) by herb farmers, and to examine the species composition of airborne microflora. Air samples were collected on glass fibre filters by use of personal samplers on 13 farms owned by herb cultivating farmers, located in Lublin province (eastern Poland). The concentrations of total viable microorganisms (bacteria + fungi) in the farm air during processing of peppermint herb were large, within a range from 895.1-6,015.8 x 10(3) cfu/m(3) (median 1,055.3 x 10(3) cfu/m(3)). During processing of chamomile herb they were much lower and varied within a range from 0.88-295.6 x 10(3) cfu/m(3) (median 27.3 x 10(3) cfu/m(3)). Gram-negative bacteria distinctly prevailed during processing of peppermint leaves, forming 46.4-88.5 % of the total airborne microflora. During processing of chamomile herb, Gram-negative bacteria were dominant at 3 out of 6 sampling sites forming 54.7-75.3 % of total microflora, whereas at the remaining 3 sites the most common were fungi forming 46.2-99.9 % of the total count. The species Pantoea agglomerans (synonyms: Erwinia herbicola, Enterobacter agglomerans ), having strong allergenic and endotoxic properties, distinctly prevailed among Gram-negative isolates. Among fungi, the most common species was Alternaria alternata. The concentrations of airborne dust and endotoxin determined on the examined herb farms were large. The concentrations of airborne dust during peppermint and chamomile processing ranged from 86.7-958.9 mg/m(3), and from 1.1-499.2 mg/m(3), respectively (medians 552.3 mg/m(3) and 12.3 mg/m(3)). The concentrations of airborne endotoxin determined during peppermint and chamomile processing were within a wide range 1.53-208.33 microg/m(3) and 0.005-2604.19 microg/m(3) respectively (medians 57.3 microg/m(3) and 0.96 microg/m(3)). In conclusion, farmers

  9. High exposure to endotoxin in farming is associated with less new-onset pollen sensitisation

    DEFF Research Database (Denmark)

    Elholm, Grethe; Schlünssen, Vivi; Doekes, Gert

    2018-01-01

    of 1113 young Danish farmers and rural controls, with a mean age of 19 years at baseline. Sensitisation to birch pollen, grass pollen, cat dander and house dust mite was measured by specific IgE levels in serum samples from baseline and at 15 years' follow-up. Changes in sensitisation were analysed...... was not associated with significant changes in cat dander and house dust mite sensitisation. CONCLUSIONS: High exposure to endotoxin during young adulthood appears to protect against new onset of pollen sensitisation, independent of childhood farm exposure....

  10. Directed evolution of an LBP/CD14 inhibitory peptide and its anti-endotoxin activity.

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    Li Fang

    Full Text Available BACKGROUND: LPS-binding protein (LBP and its ligand CD14 are located upstream of the signaling pathway for LPS-induced inflammation. Blocking LBP and CD14 binding might prevent LPS-induced inflammation. In previous studies, we obtained a peptide analog (MP12 for the LBP/CD14 binding site and showed that this peptide analog had anti-endotoxin activity. In this study, we used in vitro directed evolution for this peptide analog to improve its in vivo and in vitro anti-endotoxin activity. METHODS: We used error-prone PCR (ep-PCR and induced mutations in the C-terminus of LBP and attached the PCR products to T7 phages to establish a mutant phage display library. The positive clones that competed with LBP for CD14 binding was obtained by screening. We used both in vivo and in vitro experiments to compare the anti-endotoxin activities of a polypeptide designated P1 contained in a positive clone and MP12. RESULTS: 11 positive clones were obtained from among target phages. Sequencing showed that 9 positive clones had a threonine (T to methionine (M mutation in amino acid 287 of LBP. Compared to polypeptide MP12, polypeptide P1 significantly inhibited LPS-induced TNF-α expression and NF-κB activity in U937 cells (P<0.05. Compared to MP12, P1 significantly improved arterial oxygen pressure, an oxygenation index, and lung pathology scores in LPS-induced ARDS rats (P<0.05. CONCLUSION: By in vitro directed evolution of peptide analogs for the LBP/CD14 binding site, we established a new polypeptide (P1 with a threonine (T-to-methionine (M mutation in amino acid 287 of LBP. This polypeptide had high anti-endotoxin activity in vitro and in vivo, which suggested that amino acid 287 in the C-terminus of LBP may play an important role in LBP binding with CD14.

  11. Erythropoietin augments the cytokine response to acute endotoxin-induced inflammation in humans

    DEFF Research Database (Denmark)

    Hojman, Pernille; Taudorf, Sarah; Lundby, Carsten

    2009-01-01

    Recent studies have shown that erythropoietin (EPO) offers protection against ischemia, hemorrhagic shock and systemic inflammation in many tissues and it has been suggested that EPO has anti-inflammatory effects. With the aim of investigating the potential acute anti-inflammatory effects of EPO...... in a human in vivo model of acute systemic low-grade inflammation, we measured circulating inflammatory mediators after intravenous administration of Escherichia coli endotoxin (LPS) bolus injection (0.1 ng/kg of body weight) in young healthy male subjects. The subjects were divided into three groups...

  12. Comparison of acute effect of systemic versus intravitreal infliximab treatment in an experimental model of endotoxin-induced uveitis.

    Science.gov (United States)

    Yuksel, Erdem; Hasanreisoglu, Berati; Yuksel, Nilay; Yilmaz, Guldal; Ercin, Ugur; Bilgihan, Ayse

    2014-02-01

    In this study, we investigated the efficacy of systemic and intravitreal (IV) infliximab treatments and compared these 2 different treatment modalities in an experimental model of endotoxin-induced uveitis (EIU). Twenty-four white New Zealand rabbits were equally divided into 4 groups. Group 1 received IV injection of lipopolysaccharide (LPS), group 2 received IV injections of LPS and saline, group 3 received IV LPS and IV 2 mg/0.1 cc infliximab, and group 4 received IV LPS and 5 mg/kg intravenous infliximab. Inflammation was determined with objective and subjective tests. The subjective test was clinical determination of uveitis, the objective tests were determination of protein concentrations and tumor necrosis factor alpha (TNF-α) levels and histopathology. Clinical examination score was lower in group 3 and group 4 (4±0.6 and 3.5±1.6, respectively) when compared with group 1 (P=0.02; P=0.04, respectively) and group 2. In group 3 and 4, the aqueous and vitreous protein and TNF-α concentration measured significantly lower than group 1 and 2. In histopathologic examination, there was no statistically significant difference between group 1, 2, and 3 (3.5±0.5, 3.6±0.5, 3.6±0.5, respectively). However, the lowest histopathologic inflammation was determined in group 4 (2.5±0.5) (compared with group 1 and group 3, respectively; P=0.03; P=0.014). In a rabbit model of experimental EIU, intravenous administration of infliximab was more effective than IV route in an acute period.

  13. Enhancement of intrinsic antitumor activity in spore-endotoxin mixtures of Bacillus thuringiensis by exposure to ultraviolet radiation

    International Nuclear Information System (INIS)

    Zamola, B.; Karminski-Zamola, G.; Fuks, Z.; Kubovic, M.; Wrishcer, M.

    1985-01-01

    Irradiation of spore-endotoxin mixtures from Bacillus thuringiensis cultures at 254 nm (60 μW cm -2 ) enhances their intrinsic antitumor potency as well as that of either component. The extent of enhancement depends on the length of exposure (optimum: 35 min) and may thus be due to photochemical changes of the endotoxin protein or/and to photoproduction of additional compounds with antitumor activity. Antitumor effects, expressed as survival rates of C57BL/6 mice inoculated with Lewis' mouse lung carcinoma and subjected to treatments 24 h later, depended on the number of doses of preparations administered (mixture, separated components). (author)

  14. Dust, endotoxin, fungi, and bacteria exposure as determined by work task, season, and type of plant in a flower greenhouse

    DEFF Research Database (Denmark)

    Thilsing, T.; Madsen, A. M.; Basinas, I.

    2015-01-01

    ). Exposure to dust, endotoxin, fungi, and bacteria differed between seasons. Packing Lavandula, sticking, potting, and grading Rhipsalideae, and all examined tasks related to Campanula production except sticking increased dust exposure. Endotoxin exposure was increased during sticking Campanula and pinching...... exposure limit of 90 EU m(-3) was exceeded in 30% of the samples, which may have health implications for the employees. Exposure levels were found to vary depending on the tasks performed, and thereby results can be used to direct task-based initiatives to reduce workplace exposures....

  15. A comparison of the endotoxin biosynthesis and protein oxidation pathways in the biogenesis of the outer membrane of Escherichia coli and Neisseria meningitidis

    Directory of Open Access Journals (Sweden)

    Susannah ePiek

    2012-12-01

    Full Text Available The Gram-negative bacterial cell envelope consists of an inner membrane (IM that surrounds the cytoplasm, and an asymmetrical outer-membrane (OM that forms a protective barrier to the external environment. The OM consists of lipopolysaccahride (LPS, phospholipids, outer membrane proteins (OMPs and lipoproteins. Oxidative protein folding mediated by periplasmic oxidoreductases is required for the correct biogenesis of the protein components, mainly constituents of virulence determinants such as pili, flagella and toxins, of the Gram-negative OM. Recently, periplasmic oxidoreductases have been implicated in LPS biogenesis of Escherichia coli and Neisseria meningitidis. Differences in OM biogenesis, in particular the transport pathways for endotoxin to the OM, the composition and role of the protein oxidation and isomerisation pathways and the regulatory networks that control them have been found in these two Gram-negative species suggesting that although form and function of the OM is conserved, these conserved pathways have been modified to suit the lifestyle of each organism.

  16. TLR ligands, but not modulators of histone modifiers, can induce the complex immune response pattern of endotoxin tolerance in mammary epithelial cells

    Science.gov (United States)

    Günther, Juliane; Petzl, Wolfram; Zerbe, Holm; Schuberth, Hans-Joachim

    2016-01-01

    Excessive stimulation of the TLR4 axis through LPS reduces the expression of some cytokine genes in immune cells, while stimulating the expression of immune defense genes during a subsequent bacterial infection. This endotoxin tolerance (ET) is mediated via epigenetic mechanisms. Priming the udder of cows with LPS was shown to induce ET in mammary epithelial cells (MEC), thereby protecting the udder against reinfection for some time. Seeking alternatives to LPS priming we tried to elicit ET by priming MEC with either lipopeptide (Pam2CSK4) via the TLR2/6 axis or inhibitors of histone-modifying enzymes. Pre-incubation of MEC with Pam2CSK4 enhanced baseline and induced expression of bactericidal (β-defensin; SLPI) and membrane protecting factors (SAA3, TGM3), while reducing the expression of cytokine- and chemokine-encoding genes (TNF, IL1β) after a subsequent pathogen challenge, the latter, however, not as efficiently as after LPS priming. Pre-treating MEC with various inhibitors of histone H3 modifiers (for demethylation, acetylation or deacetylation) all failed to induce any of the protective factors and only resulted in some dampening of cytokine gene expression after the re-challenge. Hence, triggering immune functions via the TLR axis, but not through those histone modifiers, induced the beneficial phenomenon of ET in MEC. PMID:27913794

  17. Mechanisms of interleukin-2-induced hydrothoraxy in mice: protective effect of endotoxin tolerance and dexamethasone and possible role of reactive oxygen intermediates.

    Science.gov (United States)

    Faggioni, R; Allavena, P; Cantoni, L; Carelli, M; Demitri, M T; Delgado, R; Gatti, S; Gnocchi, P; Isetta, A M; Paganin, C

    1994-04-01

    Interleukin (IL)-2 is known to induce vascular leak syndrome (VLS), which was suggested to be mediated by immune system-derived cytokines, including tumor necrosis factor (TNF). To characterize the role of TNF in IL-2 toxicity in C3H/HeN mice, we used two approaches to downregulate TNF production in vivo: treatment with dexamethasone (DEX) and induction of endotoxin (lipopolysaccharide) (LPS) tolerance by a 4-day pretreatment with LPS (35 micrograms/mouse/day). Mice were then treated with IL-2 for 5 days (1.8 x 10(5) IU/mouse, twice daily). Both DEX and LPS tolerance blocked development of hydrothorax in IL-2-treated mice and inhibited TNF induction. DEX and LPS tolerance also ameliorated IL-2 toxicity in terms of decrease in food intake and inhibited the increase of the acute-phase protein, serum amyloid A (SAA). The IL-2 activation of splenic natural killer (NK) cell activity was also diminished by DEX and, to a lesser extent, by LPS-tolerance. Treatment with IL-2 also caused induction of the superoxide-generating enzyme xanthine oxidase (XO) in tissues and serum and induced bacterial translocation in the mesenteric lymph nodes (MLN). These data suggest that multiple mechanisms, including NK cell activity, cytokines, and reactive oxygen intermediates, might be important in the vascular toxicity of IL-2.

  18. 7 CFR 58.135 - Bacterial estimate.

    Science.gov (United States)

    2010-01-01

    ... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Milk § 58.135 Bacterial estimate. (a) Methods of Testing. Milk shall be tested for bacterial estimate... representative sample of each producer's milk at least once each month at irregular intervals. Samples shall be...

  19. Maternal endotoxin-induced fetal growth restriction in rats: Fetal responses in toll-like receptor

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    Banun Kusumawardani

    2012-09-01

    Full Text Available Background: Porphyromonas gingivalis as a major etiology of periodontal disease can produce virulence factor, lipopolysaccharide/LPS, which is expected to play a role in the intrauterine fetal growth. Trophoblast at the maternal-fetal interface actively participates in response to infection through the expression of a family of natural immune receptors, toll-like receptor (TLR. Purpose: the aims of study were to identify endotoxin concentration in maternal blood serum of Porphyromonas gingivalis-infected pregnant rats, to characterize the TLR-4 expression in trophoblast cells, and to determine its effect on fetal growth. Methods: Female rats were infected with live-Porphyromonas gingivalis at concentration of 2 x 109 cells/ml into subgingival sulcus area of the maxillary first molar before and/or during pregnancy. They were sacrified on 14th and 20th gestational day. Fetuses were evaluated for weight and length. Endotoxin was detected by limulus amebocyte lysate assay in the maternal blood serum. The TLR-4 expression in trophoblast cells was detected by immunohistochemistry. A System Dynamics Model to Predict the Human Monocyte Response to Endotoxins

    Directory of Open Access Journals (Sweden)

    Enrique Álvarez

    2017-08-01

    Full Text Available System dynamics is a powerful tool that allows modeling of complex and highly networked systems such as those found in the human immune system. We have developed a model that reproduces how the exposure of human monocytes to lipopolysaccharides (LPSs induces an inflammatory state characterized by high production of tumor necrosis factor alpha (TNFα, which is rapidly modulated to enter into a tolerant state, known as endotoxin tolerance (ET. The model contains two subsystems with a total of six states, seven flows, two auxiliary variables, and 14 parameters that interact through six differential and nine algebraic equations. The parameters were estimated and optimized to obtain a model that fits the experimental data obtained from human monocytes treated with various LPS doses. In contrast to publications on other animal models, stimulation of human monocytes with super-low-dose LPSs did not alter the response to a second LPSs challenge, neither inducing ET, nor enhancing the inflammatory response. Moreover, the model confirms the low production of TNFα and increased levels of C–C motif ligand 2 when monocytes exhibit a tolerant state similar to that of patients with sepsis. At present, the model can help us better understand the ET response and might offer new insights on sepsis diagnostics and prognosis by examining the monocyte response to endotoxins in patients with sepsis.

  1. Acute hemodynamic changes during lung recruitment in lavage and endotoxin-induced ALI.

    Science.gov (United States)

    Odenstedt, Helena; Aneman, Anders; Kárason, Sigurbergur; Stenqvist, Ola; Lundin, Stefan

    2005-01-01

    To assess acute cardiorespiratory effects of recruitment manoeuvres in experimental acute lung injury. Experimental study in animal models of acute lung injury. Experimental laboratory at a University Medical Centre. Ten pigs with bronchoalveolar lavage and eight pigs with endotoxin-induced ALI. Two kinds of recruitment manoeuvres during 1 min; a) vital capacity manoeuvres (ViCM) consisting in a sustained inflation at 30 cmH(2)O and 40 cmH(2)O; b) manoeuvres obtained during ongoing pressure-controlled ventilation (PCRM) with peak airway pressure 30 cmH(2)O, positive end-expiratory pressure (PEEP) 15 and peak airway pressure 40, PEEP 20. Recruitment manoeuvres were repeated after volume expansion (dextran 8 ml/kg). Oxygenation, mean arterial, and pulmonary artery pressures, aortic, mesenteric, and renal blood flow were monitored. Lower pressure recruitment manoeuvres (ViCM30 and PCRM30/15) did not significantly improve oxygenation. With ViCM and PCRM at peak airway pressure 40 cmH(2)O, PaO(2) increased to similar levels in both lavage and endotoxin groups. Aortic blood flow was reduced from baseline during PCRM40/20 and ViCM40 by 57+/-3% and 61+/-6% in the lavage group and by 57+/-8% and 82+/-7% (Pdepression may be attenuated using recruitment manoeuvres during ongoing pressure-controlled ventilation and by prior volume expansion.

  2. A System Dynamics Model to Predict the Human Monocyte Response to Endotoxins

    Science.gov (United States)

    Álvarez, Enrique; Toledano, Víctor; Morilla, Fernando; Hernández-Jiménez, Enrique; Cubillos-Zapata, Carolina; Varela-Serrano, Aníbal; Casas-Martín, José; Avendaño-Ortiz, José; Aguirre, Luis A.; Arnalich, Francisco; Maroun-Eid, Charbel; Martín-Quirós, Alejandro; Quintana Díaz, Manuel; López-Collazo, Eduardo

    2017-01-01

    System dynamics is a powerful tool that allows modeling of complex and highly networked systems such as those found in the human immune system. We have developed a model that reproduces how the exposure of human monocytes to lipopolysaccharides (LPSs) induces an inflammatory state characterized by high production of tumor necrosis factor alpha (TNFα), which is rapidly modulated to enter into a tolerant state, known as endotoxin tolerance (ET). The model contains two subsystems with a total of six states, seven flows, two auxiliary variables, and 14 parameters that interact through six differential and nine algebraic equations. The parameters were estimated and optimized to obtain a model that fits the experimental data obtained from human monocytes treated with various LPS doses. In contrast to publications on other animal models, stimulation of human monocytes with super-low-dose LPSs did not alter the response to a second LPSs challenge, neither inducing ET, nor enhancing the inflammatory response. Moreover, the model confirms the low production of TNFα and increased levels of C–C motif ligand 2 when monocytes exhibit a tolerant state similar to that of patients with sepsis. At present, the model can help us better understand the ET response and might offer new insights on sepsis diagnostics and prognosis by examining the monocyte response to endotoxins in patients with sepsis. PMID:28824640

  3. Interaction between resource identity and bacterial community composition regulates bacterial respiration in aquatic ecosystems

    Directory of Open Access Journals (Sweden)

    A. P. F. Pires

    Full Text Available Abstract Resource identity and composition structure bacterial community, which in turn determines the magnitude of bacterial processes and ecological services. However, the complex interaction between resource identity and bacterial community composition (BCC has been poorly understood so far. Using aquatic microcosms, we tested whether and how resource identity interacts with BCC in regulating bacterial respiration and bacterial functional diversity. Different aquatic macrophyte leachates were used as different carbon resources while BCC was manipulated through successional changes of bacterial populations in batch cultures. We observed that the same BCC treatment respired differently on each carbon resource; these resources also supported different amounts of bacterial functional diversity. There was no clear linear pattern of bacterial respiration in relation to time succession of bacterial communities in all leachates, i.e. differences on bacterial respiration between different BCC were rather idiosyncratic. Resource identity regulated the magnitude of respiration of each BCC, e.g. Ultricularia foliosa leachate sustained the greatest bacterial functional diversity and lowest rates of bacterial respiration in all BCC. We conclude that both resource identity and the BCC interact affecting the pattern and the magnitude of bacterial respiration in aquatic ecosystems.

  4. Structure and function of cerebral and mesenteric resistance arteries in low-dose endotoxin-infused pregnant rats

    NARCIS (Netherlands)

    Wiegman, Marjon J; Van der Graaf, Anne Marijn; Henning, Robert H.; Zeeman, Gerda G.; Buikema, Hendrik; Faas, Marijke M.

    Objective: Since the cerebrovasculature likely plays a prominent role in the pathophysiology of eclampsia, we assessed the effects of low-dose endotoxin-induced experimental preeclampsia on the function and structure of rat posterior cerebral arteries (PCA) and mesenteric arteries (MA). Methods:

  5. A hybrid Bacillus thuringiensis delta-endotoxin gene gives resistance against a coleopteran and a lepidopteran pest in transgenic potato

    NARCIS (Netherlands)

    Naimov, S.; Dukiandjiev, S.; Maagd, de R.A.

    2003-01-01

    Expression of Bacillus thuringiensis delta-endotoxins has proven to be a successful strategy for obtaining insect resistance in transgenic plants. Drawbacks of expression of a single resistance gene are the limited target spectrum and the potential for rapid adaptation of the pest. Hybrid toxins

  6. Characterization of the pH-Mediated solubility of Bacillus thuringiensis var. san diego native δ-endotoxin crystals

    Science.gov (United States)

    C. N. Koller; L. S. Bauer; R. M. Hollingworth

    1992-01-01

    Native crystals of Bacillus thuringiensis var. san diego, a coleopteran-specific δ-endotoxin, were metabolically labeled with [35S]methionine. Specific activity was 82,000 CPM/μg (2.44 Ci/mmol). Using a universal buffer formulated with the same ionic strength at every pH, we determined that...

  7. Endotoxin removal using 6,000 molecular weight cut-off polyacrylonitrile (PAN) and polysulfone (PS) hollow fiber ultrafilters.

    Science.gov (United States)

    Evans-Strickfaden, T T; Oshima, K H; Highsmith, A K; Ades, E W

    1996-01-01

    The removal of pyrogenic and microbial contaminants from high purity water and parental solutions during production is a concern to pharmaceutical manufacturers. In a previous study, 6000 molecular weight cut-off (MWCO) polyacrylonitrile (PAN) and polysulfone (PS) ultrafilters were shown to remove poliovirus (Titer reduction [Tr], > 6 logs) and phages T1 and PP7 (Tr, 7 logs) from ultrapure water, 0.85% saline with 1% trypicase soy broth, and Dulbecco's Eagle minimal essential medium with 10% fetal bovine serum (15). In this study, we evaluated the ability of the 6,000 MWCO PAN and PS ultrafilters to remove purified endotoxin (Escherichia coli lipopolysaccharide) which was added to commercial Water for Irrigation. An endotoxin concentration reduction of > 6 logs was achieved with both PAN and PS ultrafilters (detection sensitivity, 0.0031 EU/ml) when a minimum of 3.92 x 10(3) EU/ml of endotoxin was added to Water for Irrigation. These results indicate that the 6,000 MWCO PAN and PS ultrafilters are very effective in removing endotoxin from fluids such as Water for Irrigation.

  8. Bacillus thuringiensis delta-endotoxin Cry1 hybrid proteins with increased activity against the Colorado potato beetle

    NARCIS (Netherlands)

    Naimov, S.; Weemen-Hendriks, M.; Dukiandjiev, S.; Maagd, de R.A.

    2001-01-01

    Cry1 delta-endotoxins of Bacillus thuringiensis are generally active against lepidopteran insects, but Cry1Ba and Cry1Ia have additional, though low, levels of activity against coleopterans such as the Colorado potato beetle. Here we report the construction of Cry1Ba/Cry1Ia hybrid toxins which have

  9. GLOMERULAR INFLAMMATION IN PREGNANT RATS AFTER INFUSION OF LOW-DOSE ENDOTOXIN - AN IMMUNOHISTOLOGICAL STUDY IN EXPERIMENTAL PREECLAMPSIA

    NARCIS (Netherlands)

    FAAS, MM; SCHUILING, GA; BALLER, JFW; BAKKER, WW

    1995-01-01

    Increased endotoxin sensitivity during pregnancy occurs in many animals, including rats. The mechanism of this phenomenon is not understood. In the present study it was investigated whether this increased sensitivity is reflected by an altered inflammatory pattern. Inflammatory cell influx, the

  10. Single-use membrane adsorbers for endotoxin removal and purification of endogenous polysialic acid from Escherichia coli K1

    Directory of Open Access Journals (Sweden)

    Ingo de Vries

    2018-03-01

    After downstream processing the final product had neither detectable protein nor DNA contamination. Endotoxin content was below 3 EU mg−1. Investigation of the maximal chain length showed no effect of the harsh sodium hydroxide treatment during DSP on the stability of the polySia. Maximal chain length was ∼98 degree of polymerization.

  11. The Effects of the ND:YAG Laser on In vitro Fibroblast Attachment to Endotoxin Treated Root Surfaces

    Science.gov (United States)

    1991-05-01

    Preparation and Incubation .................................. 17 Scanning Electron Microscopic Observation 17 Data Collection and Analysis...fluorescence was seen regardless of the incubation time or endotoxin concentration. Brushing for one minute with a soft toothbrush removed most of the...However, the surface was brittle and fusion of enamel was not accomplished. Craters were produced at the point of laser impact . Peck and Peck (1967

  12. Spatial and temporal variation in endotoxin and PM10 concentrations in ambient air in a livestock dense area

    NARCIS (Netherlands)

    de Rooij, Myrna; Heederik, Dick|info:eu-repo/dai/nl/072910542; Borlée, Floor|info:eu-repo/dai/nl/315138661; Hoek, Gerard|info:eu-repo/dai/nl/069553475; Wouters, Inge|info:eu-repo/dai/nl/274156652

    Several studies have reported associations between farming and respiratory health in neighboring residents. Health effects are possibly linked to fine dust and endotoxin emissions from livestock farms. Little is known about levels of these air pollutants in ambient air in livestock dense areas. We

  13. Kinetics of intraocular tumor necrosis factor and interleukin-6 in endotoxin-induced uveitis in the rat

    NARCIS (Netherlands)

    de Vos, A. F.; van Haren, M. A.; Verhagen, C.; Hoekzema, R.; Kijlstra, A.

    1994-01-01

    To determine the kinetics of tumor necrosis factor (TNF) and interleukin-6 (IL-6) in serum and aqueous humor of rats with different susceptibilities to endotoxin-induced uveitis (EIU), after footpad injection of lipopolysaccharide (LPS). Samples were collected from EIU-susceptible Lewis rats and

  14. T-bet expression in the iris and spleen parallels disease expression during endotoxin-induced uveitis

    NARCIS (Netherlands)

    Li, B.; Yang, P.; Chu, L.; Zhou, H.; Huang, X.; Zhu, L.; Kijlstra, A.

    2007-01-01

    T lymphocytes have been implicated in the development of endotoxin-induced uveitis (EIU). T-bet is a Th1 cell-specific transcription factor that is involved in differentiation and effector functions. The aim of this study was to investigate kinetics of T-bet expression at the mRNA and protein levels

  15. Aplicabilidade do Teste de Ativação de Monócitos (MAT no Brasil: importância da sua utilização como teste para detecção de pirogênios no controle da qualidade de produtos injetáveis | Applicability of the Monocyte Activation Test (MAT in Brazil: the importance of its use as a test for the detection of pyrogens in the quality control of injectable products

    Directory of Open Access Journals (Sweden)

    Cristiane Caldeira da Silva

    2015-08-01

    kick-off study for future studies. Products’ monographs in pharmacopeias in the United States, Europe, and Brazil that are recommended for RPT or Bacterial Endotoxins Test (BET are as follows. RPT: 20 in American, 37 in European, and 28 in Brazilian pharmacopoeias. BET: 619 in American, 157 in European, and 41 in Brazilian pharmacopoeias. Four products require pyrogenicity testing in three pharmacopoeias. Both RPT and BET are recommended by six monographs in Brazilian pharmacopeias and 15 in European pharmacopoeias. In Brazilian pharmacopoeias most are biological. These products should be the first to be tested for their applicability to MAT because they are currently tested mainly by RPT.

  16. Evidence of bacterial biofilm in tubing from hydraulic pathway of hemodialysis system.

    Science.gov (United States)

    Man, N K; Degremont, A; Darbord, J C; Collet, M; Vaillant, P

    1998-07-01

    Biofilms consist of microorganisms immobilized at a substratum surface embedded in an organic polymer matrix of bacterial origin. Tubing drawn from the fluid pathways within dialysis machines of various models were investigated for biofilm. Scanning electron microscopy (SEM), performed on approximately 2 cm2 samples of the tubing inner surfaces revealed that the inner surfaces of the tubing were covered with biofilms consisting of numerous deposits and glycocalix at different stages of formation with components containing bacteria and algae. Evaluations of biomass were performed from tubing sections of various lengths and inner diameters put in tubes containing water for injection and immersed in an ultrasound washtub for 1 h to ensure sloughing of the biofilm. Living bacteria were identified by plating on nutrient agar media and incubation for 48 h at 37 degrees C. Epifluorescent stains were used for the total bacteria count. Lipopolysaccharide levels were determined by the endotoxin activity measurements. Polyoside contents were determined by the colometric method, and the chemical oxygen demand was measured to evaluate the amount of organic substance. Biofilms detached from tubing samples drawn from the water path, bicarbonate path, and fresh dialysate path within dialysis machines contained approximately 1.10(3)-1.10(6) total bacteria/cm2, yet only some living bacteria were found. Endotoxin levels ranged from 1 to 12 EU/cm2. In contrast in the dialysate fluid, no bacteria were found, and the endotoxin content was under the detection level of the method. The polyoside content and chemical oxygen demand of the biomass ranged from 11 to 83 microg/cm2 and from 53 to 234 mg/cm2, respectively. It is concluded that a germ- and endotoxin-free dialysate does not exclude the risks and hazards of bacteria and endotoxin discharge from biofilm developed on the fluid pathway tubing, acting as a reservoir for continuous contamination, and efforts in the optimization of

  17. Endotoxin and interferon-γ inhibit translation in skeletal muscle cells by stimulating nitric oxide synthase activity

    Science.gov (United States)

    Frost, Robert A.; Nystrom, Gerald J.; Lang, Charles H.

    2012-01-01

    The purpose of the present study was to test the hypothesis that endogenous nitric oxide (NO) negatively affects translation in skeletal muscle cells after exposure to a combination of endotoxin (LPS) and interferon (IFN)γ. Individually LPS and IFNγ did not alter protein synthesis but in combination they inhibited protein synthesis by 80% in C2C12 myotubes. The combination of LPS and IFNγ dramatically down regulated the auto-phosphorylation of the mammalian target of rapamycin (mTOR) and its substrates S6K1 and 4EBP-1. The phosphorylation of ribosomal protein S6 was decreased whereas phosphorylation of elongation factor-2 (eEF-2) and raptor was enhanced consistent with defects in both translation initiation and elongation. Reduced S6 phosphorylation occurred 8–18 h after LPS/IFNγ and coincided with a prolonged upregulation of NOS2 mRNA and protein. NOS2 protein expression and the LPS/IFNγ –induced fall in phosphorylated S6 were prevented by the proteasome inhibitor MG132. The general NOS inhibitor L-NAME and the specific NOS2 inhibitor 1400W also prevented the LPS/IFNγ-induced decrease in protein synthesis and restored translational signaling. LPS/IFNγ down regulated the phosphorylation of multiple Akt substrates including the proline rich Akt substrate-40 (PRAS40) while enhancing the phosphorylation of raptor on an AMPK regulated site. The negative effects of LPS/IFNγ were blunted by the AMPK inhibitor compound C. The data suggest that in combination LPS and IFNγ induce a prolonged expression of NOS2 and excessive production of NO that reciprocally alters Akt and AMPK activity and consequently down regulates translation via reduced mTOR signaling. PMID:19295495

  18. Macromolecular interactions of the bacterial division FtsZ protein: from quantitative biochemistry and crowding to reconstructing minimal divisomes in the test tube.

    Science.gov (United States)

    Rivas, Germán; Alfonso, Carlos; Jiménez, Mercedes; Monterroso, Begoña; Zorrilla, Silvia

    2013-06-01

    The division of Escherichia coli is an essential process strictly regulated in time and space. It requires the association of FtsZ with other proteins to assemble a dynamic ring during septation, forming part of the functionally active division machinery, the divisome. FtsZ reversibly interacts with FtsA and ZipA at the cytoplasmic membrane to form a proto-ring, the first molecular assembly of the divisome, which is ultimately joined by the rest of the division-specific proteins. In this review we summarize the quantitative approaches used to study the activity, interactions, and assembly properties of FtsZ under well-defined solution conditions, with the aim of furthering our understanding of how the behavior of FtsZ is controlled by nucleotides and physiological ligands. The modulation of the association and assembly properties of FtsZ by excluded-volume effects, reproducing in part the natural crowded environment in which this protein has evolved to function, will be described. The subsequent studies on the reactivity of FtsZ in membrane-like systems using biochemical, biophysical, and imaging technologies are reported. Finally, we discuss the experimental challenges to be met to achieve construction of the minimum protein set needed to initiate bacterial division, without cells, in a cell-like compartment. This integrated approach, combining quantitative and synthetic strategies, will help to support (or dismiss) conclusions already derived from cellular and molecular analysis and to complete our understanding on how bacterial division works.

  19. Endogenous bacterial toxins are required for the injurious action of platelet-activating factor in rats.

    Science.gov (United States)

    Sun, X M; MacKendrick, W; Tien, J; Huang, W; Caplan, M S; Hsueh, W

    1995-07-01

    Platelet-activating factor (PAF), an endogenous mediator for experimental sepsis, has been shown to induce shock and intestinal necrosis in vivo. However, it is unclear whether PAF exerts its injurious effects on the intestinal tissue directly or via synergism with other endogenous products. The aim of this study was to examine the role of endogenous bacterial products, such as endotoxin, in PAF-induced intestinal injury. PAF (3 micrograms/kg) was injected intravenously into normally colonized rats, germfree rats, and normal rats pretreated with a combination of antibiotics, and the systemic response and intestinal injury were assessed. PAF did not cause prolonged shock, leukopenia, hemoconcentration, and bowel necrosis in germfree rats. When germfree rats were primed with a low dose (0.5 mg/kg) of endotoxin, the protection was lost. Combined treatment of the normally colonized rats with neomycin, polymyxin B, and metronidazole for 7 days largely protected the animal from PAF-induced shock and intestinal necrosis. PAF does not directly induce prolonged hypotension, hemoconcentration, persistent leukopenia, and gross intestinal necrosis but causes these changes via a synergism with endogenous bacterial toxins, presumably from the gut flora.

  20. Susceptibility of Some Bacterial Contaminants Recovered from ...

    African Journals Online (AJOL)

    Purpose: To investigate the susceptibility of bacterial contaminants recovered from cosmetics to preservatives and antibiotics. Methods: Nine bacterial isolates recovered from various brands of commercially available cosmetics marketed in Jordan were tested for their susceptibility pattern against two paraben esters and two ...

  1. Susceptibility of Some Bacterial Contaminants Recovered from ...

    African Journals Online (AJOL)

    Purpose: To investigate the susceptibility of bacterial contaminants recovered from cosmetics to preservatives and antibiotics. Methods: Nine bacterial isolates recovered from various brands of commercially available cosmetics marketed in Jordan were tested for their susceptibility pattern against two paraben esters and two.

  2. Metagenomic Diagnosis of Bacterial Infections

    Science.gov (United States)

    Nakamura, Shota; Maeda, Norihiro; Miron, Ionut Mihai; Yoh, Myonsun; Izutsu, Kaori; Kataoka, Chidoh; Honda, Takeshi; Yasunaga, Teruo; Nakaya, Takaaki; Kawai, Jun; Hayashizaki, Yoshihide; Horii, Toshihiro

    2008-01-01

    To test the ability of high-throughput DNA sequencing to detect bacterial pathogens, we used it on DNA from a patient’s feces during and after diarrheal illness. Sequences showing best matches for Campylobacter jejuni were detected only in the illness sample. Various bacteria may be detectable with this metagenomic approach. PMID:18976571

  3. Adsorption of endotoxins on Ca2+ -iminodiacetic acid by metal ion affinity chromatography.

    Science.gov (United States)

    Lopes, André Moreni; Romeu, Jorge Sánchez; Meireles, Rolando Páez; Perera, Gabriel Marquez; Morales, Rolando Perdomo; Pessoa, Adalberto; Cárdenas, Lourdes Zumalacárregui

    2012-11-01

    Endotoxins (also known as lipopolysaccharides (LPS)) are undesirable by-products of recombinant proteins, purified from Escherichia coli. LPS can be considered stable under a wide range of temperature and pH, making their removal one of the most difficult tasks in downstream processes during protein purification. The inherent toxicity of LPS makes their removal an important step for the application of these proteins in several biological assays and for a safe parenteral administration. Immobilized metal affinity chromatography (IMAC) enables the affinity interactions between the metal ions (immobilized on the support through the chelating compound) and the target molecules, thus enabling high-efficiency separation of the target molecules from other components present in a mixture. Affinity chromatography is applied with Ca2+ -iminodiacetic acid (IDA) to remove most of the LPS contaminants from the end product (more than 90%). In this study, the adsorption of LPS on an IDA-Ca2+ was investigated. The adsorption Freundlich isotherm of LPS-IDA-Ca2+ provides a theoretical basis for LPS removal. It was found that LPS is bound mainly by interactions between the phosphate group in LPS and Ca2+ ligands on the beads. The factors such as pH (4.0 or 5.5) and ionic strength (1.0 mol/L) are essential to obtain effective removal of LPS for contaminant levels between endotoxin' concentration values less than 100 EU/mL and 100 000 EU/mL. This new protocol represents a substantial advantage in time, effort, and production costs.

  4. 40 CFR 180.1154 - CryIA(c) and CryIC derived delta-endotoxins of Bacillus thuringiensis var. kurstaki encapsulated...

    Science.gov (United States)

    2010-07-01

    ...-endotoxins of Bacillus thuringiensis var. kurstaki encapsulated in killed Pseudomonas fluorescens, and the... Bacillus thuringiensis var. kurstaki encapsulated in killed Pseudomonas fluorescens, and the expression... thuringiensis var. kurstaki encapsulated in killed Pseudomonas fluorescens and the expression plasmid and...

  5. OK-432 reduces mortality and bacterial translocation in irradiated and granulocyte-colony stimulating factor (G-CSF)-treated mice

    International Nuclear Information System (INIS)

    Nose, Masako; Uzawa, Akiko; Ogyu, Toshiaki; Suzuki, Gen

    2001-01-01

    Acute radiation induces bacterial translocation from the gut, followed by systemic infection and sepsis. In order to reduce the mortality after acute whole body irradiation, it is essential to control bacterial translocation. In this study, we established a bacterial translocation assay as a sensitive method to detect minor mucosal injury by radiation. By utilizing this assay, we evaluated the adverse effects, if any, of hematopoietic reagents on the mucosal integrity in the respiratory and gastro-intestinal tracts. Bacterial translocation to the liver and spleen occurred after whole-body irradiation if the dose exceeded 6 Gy. The administration of G-CSF unexpectedly increased the bacterial translocation in 8 Gy-irradiated mice. The pharmaceutical preparation of low-virulent Streptococcus pyogenes, OK-432, significantly reduced the endotoxin levels in peripheral blood without any reduction of bacterial translocation. A combined treatment with G-CSF and OK-432 decreased bacterial translocation and prevented death. This result indicates that the early administration of G-CSF has an adverse effect on bacterial translocation, and that a combined treatment of G-CSF and OK-432 attenuates the adverse effect of G-CSF and improves the survival rate after acute irradiation. (author)

  6. OK-432 reduces mortality and bacterial translocation in irradiated and granulocyte-colony stimulating factor (G-CSF)-treated mice

    Energy Technology Data Exchange (ETDEWEB)

    Nose, Masako; Uzawa, Akiko; Ogyu, Toshiaki [National Inst. of Radiological Sciences, Chiba (Japan); Suzuki, Gen

    2001-06-01

    Acute radiation induces bacterial translocation from the gut, followed by systemic infection and sepsis. In order to reduce the mortality after acute whole body irradiation, it is essential to control bacterial translocation. In this study, we established a bacterial translocation assay as a sensitive method to detect minor mucosal injury by radiation. By utilizing this assay, we evaluated the adverse effects, if any, of hematopoietic reagents on the mucosal integrity in the respiratory and gastro-intestinal tracts. Bacterial translocation to the liver and spleen occurred after whole-body irradiation if the dose exceeded 6 Gy. The administration of G-CSF unexpectedly increased the bacterial translocation in 8 Gy-irradiated mice. The pharmaceutical preparation of low-virulent Streptococcus pyogenes, OK-432, significantly reduced the endotoxin levels in peripheral blood without any reduction of bacterial translocation. A combined treatment with G-CSF and OK-432 decreased bacterial translocation and prevented death. This result indicates that the early administration of G-CSF has an adverse effect on bacterial translocation, and that a combined treatment of G-CSF and OK-432 attenuates the adverse effect of G-CSF and improves the survival rate after acute irradiation. (author)

  7. Bacterial contamination of blood products.

    Science.gov (United States)

    Palavecino, Elizabeth; Jacobs, Michael; Yomtovian, Roslyn

    2004-11-01

    The occurrence of a septic reaction resulting from bacterial contamination of blood products, particularly with room-temperature stored platelets, is the most common transfusion-associated infectious risk in the United States. Bacterial contamination of blood products was first identified more than 60 years ago; yet, strategies to resolve this problem have proved daunting despite ongoing awareness and increasing concern especially in the last few years. With the recent US Food and Drug Administration (FDA) approval of culture methods for quality control testing of platelet units and the promulgation of accreditation standards by the College of American Pathologists and American Association of Blood Banks to detect bacterially contaminated platelet units and to prevent transfusion of these units, blood banks and transfusion services have finally started to address this problem, in a more standardized manner. Furthermore, as new methods of interdicting, inactivating and detecting bacterially contaminated blood products emerge, it is hoped that the problem of bacterial contamination of blood products will be overcome.

  8. Community-acquired bacterial meningitis.

    Science.gov (United States)

    Costerus, Joost M; Brouwer, Matthijs C; Bijlsma, Merijn W; van de Beek, Diederik

    2017-02-01

    Bacterial meningitis is a medical emergency and is associated with a high disease burden. We reviewed recent progress in the management of patients with community-acquired bacterial meningitis. The worldwide burden of disease of bacterial meningitis remains high, despite the decreasing incidence following introduction of routine vaccination campaigns. Delay in diagnosis and treatment remain major concerns in the management of acute bacterial meningitis. European Society of Clinical Microbiology and Infectious Diseases guidelines strive for a door-to-antibiotic-time less than 1 h. Polymerase chain reaction (PCR) has emerged as an important diagnostic tool to identify the causative organism. Point-of-care tests using fast multiplex PCR have been developed, but additional value has not been proven. Although anecdotal observations advocate pressure-based management, a randomized controlled trial will need to be performed first to determine efficacy and safety of such an aggressive treatment approach. Adjunctive dexamethasone remains the only adjunctive therapy with proven efficacy. The incidence of bacterial meningitis has been decreasing after the implementation of effective vaccines. Treatment should be administered as soon as possible and time to treatment should not exceed 1 h.

  9. Estimation of test characteristics of real-time PCR and bacterial culture for diagnosis of subclinical intramammary infections with Streptococcus agalactiae in Danish dairy cattle in 2012 using latent class analysis

    DEFF Research Database (Denmark)

    Mahmmod, Yasser; Toft, Nils; Katholm, Jørgen

    2013-01-01

    definition of infection may reflect a more general condition of cows being positive for S. agalactiae. Our findings indicate that PCR Ct-value cut-offs should be chosen according to the underlying latent infection definition of interest. Latent class analysis proposes a useful alternative to classic test......The misdiagnosis of intramammary infections (IMI) with Streptococcus agalactiae (S. agalactiae) could lead farmers to treat or cull animals unnecessarily. The objective of this field study was to estimate the sensitivity (Se) and specificity (Sp) of real-time PCR at different cut-offs for cycle...... threshold (Ct) values against bacterial culture (BC) for diagnosis of S. agalactiae IMI using latent class analysis to avoid the assumption of a perfect reference test. A total of 614 dairy cows were randomly selected from 6 herds with bulk tank PCR Ct value ≤ 39 for S. agalactiae and S. aureus. At milk...

  10. Prevention of bacterial adhesion

    DEFF Research Database (Denmark)

    Klemm, Per; Vejborg, Rebecca Munk; Hancock, Viktoria

    2010-01-01

    Management of bacterial infections is becoming increasingly difficult due to the emergence and increasing prevalence of bacterial pathogens that are resistant to available antibiotics. Conventional antibiotics generally kill bacteria by interfering with vital cellular functions, an approach...... that imposes selection pressure for resistant bacteria. New approaches are urgently needed. Targeting bacterial virulence functions directly is an attractive alternative. An obvious target is bacterial adhesion. Bacterial adhesion to surfaces is the first step in colonization, invasion, and biofilm formation....... As such, adhesion represents the Achilles heel of crucial pathogenic functions. It follows that interference with adhesion can reduce bacterial virulence. Here, we illustrate this important topic with examples of techniques being developed that can inhibit bacterial adhesion. Some of these will become...

  11. Bacterial and fungal markers in tobacco smoke

    Energy Technology Data Exchange (ETDEWEB)

    Szponar, B., E-mail: szponar@iitd.pan.wroc.pl [Lund University, Dept. of Laboratory Medicine, Soelvegatan 23, 223 62 Lund (Sweden); Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Rudolfa Weigla 12, 53-114 Wroclaw (Poland); Pehrson, C.; Larsson, L. [Lund University, Dept. of Laboratory Medicine, Soelvegatan 23, 223 62 Lund (Sweden)

    2012-11-01

    Previous research has demonstrated that cigarette smoke contains bacterial and fungal components including lipopolysaccharide (LPS) and ergosterol. In the present study we used gas chromatography-mass spectrometry to analyze tobacco as well as mainstream and second hand smoke for 3-hydroxy fatty acids (3-OH FAs) of 10 to 18 carbon chain lengths, used as LPS markers, and ergosterol, used as a marker of fungal biomass. The air concentrations of LPS were 0.0017 nmol/m{sup 3} (N = 5) and 0.0007/m{sup 3} (N = 6) in the smoking vs. non-smoking rooms (p = 0.0559) of the studied private houses, and 0.0231 nmol/m{sup 3} (N = 5) vs. 0.0006 nmol/m{sup 3} (N = 5) (p = 0.0173), respectively, at the worksite. The air concentrations of ergosterol were also significantly higher in rooms with ongoing smoking than in rooms without smoking. A positive correlation was found between LPS and ergosterol in rooms with smoking but not in rooms without smoking. 3-OH C14:0 was the main 3-OH FA, followed by 3-OH C12:0, both in mainstream and second hand smoke and in phenol:water smoke extracts prepared in order to purify the LPS. The Limulus activity of the phenolic phase of tobacco was 3900 endotoxin units (EU)/cigarette; the corresponding amount of the smoke, collected on filters from 8 puffs, was 4 EU/cigarette. Tobacco smoking has been associated with a range of inflammatory airway conditions including COPD, asthma, bronchitis, alveolar hypersensitivity etc. Significant levels of LPS and ergosterol were identified in tobacco smoke and these observations support the hypothesis that microbial components of tobacco smoke contribute to inflammation and airway disease. -- Highlights: Black-Right-Pointing-Pointer Air concentration of bacterial and fungal markers is significantly higher in rooms with ongoing smoking than without smoking. Black-Right-Pointing-Pointer Bacterial LPS correlates with fungal marker in rooms with ongoing smoking but not without smoking. Black-Right-Pointing-Pointer LPS

  12. Antibacterial compounds of Canadian honeys target bacterial cell wall inducing phenotype changes, growth inhibition and cell lysis that resemble action of β-lactam antibiotics.

    Directory of Open Access Journals (Sweden)

    Katrina Brudzynski

    Full Text Available Honeys show a desirable broad spectrum activity against Gram-positive and negative bacteria making antibacterial activity an intrinsic property of honey and a desirable source for new drug development. The cellular targets and underlying mechanism of action of honey antibacterial compounds remain largely unknown. To facilitate the target discovery, we employed a method of phenotypic profiling by directly comparing morphological changes in Escherichia coli induced by honeys to that of ampicillin, the cell wall-active β-lactam of known mechanism of action. Firstly, we demonstrated the purity of tested honeys from potential β-lactam contaminations using quantitative LC-ESI-MS. Exposure of log-phase E. coli to honey or ampicillin resulted in time- and concentration-dependent changes in bacterial cell shape with the appearance of filamentous phenotypes at sub-inhibitory concentrations and spheroplasts at the MBC. Cell wall destruction by both agents, clearly visible on microscopic micrographs, was accompanied by increased permeability of the lipopolysaccharide outer membrane as indicated by fluorescence-activated cell sorting (FACS. More than 90% E. coli exposed to honey or ampicillin became permeable to propidium iodide. Consistently with the FACS results, both honey-treated and ampicillin-treated E. coli cells released lipopolysaccharide endotoxins at comparable levels, which were significantly higher than controls (p<0.0001. E. coli cells transformed with the ampicillin-resistance gene (β-lactamase remained sensitive to honey, displayed the same level of cytotoxicity, cell shape changes and endotoxin release as ampicillin-sensitive cells. As expected, β-lactamase protected the host cell from antibacterial action of ampicillin. Thus, both honey and ampicillin induced similar structural changes to the cell wall and LPS and that this ability underlies antibacterial activities of both agents. Since the cell wall is critical for cell growth and

  13. Disease Severity in Patients with Simultaneous Influenza and Bacterial Pneumonia

    OpenAIRE

    Seki, Masafumi; Kosai, Kosuke; Yanagihara, Katsunori; Higashiyama, Yasuhito; Kurihara, Shintaro; Izumikawa, Koichi; Miyazaki, Yoshitsugu; Hirakata, Yoichi; Tashiro, Takayoshi; Kohno, Shigeru

    2007-01-01

    Objective To determine the differences in the clinical features of bacterial pneumonia patients between patients co-infected with influenza virus or not co-infected. Methods Fifteen adult patients with bacterial pneumonia (7 men and 8 women) who also tested positive for influenza virus antigen were compared with those with bacterial pneumonia alone (n=28). Results Complications with chronic lung diseases were more frequently found in bacterial pneumonia patients with influenza virus infection...

  14. Chlorogenic acid from honeysuckle improves hepatic lipid dysregulation and modulates hepatic fatty acid composition in rats with chronic endotoxin infusion.

    Science.gov (United States)

    Zhou, Yan; Ruan, Zheng; Wen, Yanmei; Yang, Yuhui; Mi, Shumei; Zhou, Lili; Wu, Xin; Ding, Sheng; Deng, Zeyuan; Wu, Guoyao; Yin, Yulong

    2016-03-01

    Chlorogenic acid as a natural hydroxycinnamic acid has protective effect for liver. Endotoxin induced metabolic disorder, such as lipid dysregulation and hyperlipidemia. In this study, we investigated the effect of chlorogenic acid in rats with chronic endotoxin infusion. The Sprague-Dawley rats with lipid metabolic disorder (LD group) were intraperitoneally injected endotoxin. And the rats of chlorogenic acid-LD group were daily received chlorogenic acid by intragastric administration. In chlorogenic acid-LD group, the area of visceral adipocyte was decreased and liver injury was ameliorated, as compared to LD group. In chlorogenic acid-LD group, serum triglycerides, free fatty acids, hepatic triglycerides and cholesterol were decreased, the proportion of C20:1, C24:1 and C18:3n-6, Δ9-18 and Δ6-desaturase activity index in the liver were decreased, and the proportion of C18:3n-3 acid was increased, compared to the LD group. Moreover, levels of phosphorylated AMP-activated protein kinase, carnitine palmitoyltransferase-I, and fatty acid β-oxidation were increased in chlorogenic acid-LD group compared to LD rats, whereas levels of fatty acid synthase and acetyl-CoA carboxylase were decreased. These findings demonstrate that chlorogenic acid effectively improves hepatic lipid dysregulation in rats by regulating fatty acid metabolism enzymes, stimulating AMP-activated protein kinase activation, and modulating levels of hepatic fatty acids.

  15. The effect of taurine on the relationship between NO, ADMA and homocysteine in endotoxin-mediated inflammation in HUVEC cultures.

    Science.gov (United States)

    Pasaoglu, Ozge Tugce; Turkozkan, Nurten; Ark, Mustafa; Polat, Belgin; Agilli, Mehmet; Yaman, Halil

    2014-10-01

    The aim of our study was to investigate the effect of taurine on the relationship between nitric oxide (NO), asymmetric dimethylarginine (ADMA) and homocysteine (Hcy) in endotoxin-induced human umblical vein endothelial cell (HUVEC) cultures. For this reason, four groups were formed (n=12). Control group consists of HUVEC cultures without any treatment. Lipopolysaccharide (LPS) and LPS+taurine groups were treated with 10 μg/mL endotoxin, 5 μg/mL taurine and endotoxin+taurine (same doses), respectively. Nitrite/nitrate (NOx), ADMA and Hcy levels were measured. There was a significant increase of NOx, ADMA and Hcy in endotoxemia (pTaurine treatment elevated NOx levels significantly (ptaurine and LPS + taurine group compared to control group, while it reduced NOx levels compared to LPS group. In contrast, taurine decreased ADMA levels to the control level both in taurine and taurine+LPS group compared to LPS. Hcy levels increased significantly compared to taurine group (pTaurine was effective on ADMA-NO relationship whereas no beneficial effect was observed in Hcy levels (p<0.05).

  16. Optimization and evaluation of Flexicult(®) Vet for detection, identification and antimicrobial susceptibility testing of bacterial uropathogens in small animal veterinary practice

    DEFF Research Database (Denmark)

    Guardabassi, Luca; Hedberg, Sandra; Jessen, Lisbeth Rem

    2015-01-01

    -pathogens in veterinary practice. METHODS: Seventy-two urine samples from dogs and cats with suspected UTI presenting to seven veterinary facilities were used by clinical staff and an investigator to estimate sensitivity and specificity of Flexicult Vet A compared to laboratory reference standards for culture...... B (commercial name Flexicult(®) Vet) is a time- and cost-effective point-of-care test to guide antimicrobial choice and facilitate implementation of antimicrobial use guidelines for treatment of UTIs in small animals, provided that clinical staff is adequately trained to interpret the results...... and susceptibility testing. Subsequently, the test was modified by inclusion of an oxacillin-containing compartment for detection of methicillin-resistant staphylococci. The performance of the modified product (Flexicult Vet B) for susceptibility testing was evaluated in vitro using a collection of 110 clinical...

  17. Phorbol myristate acetate stimulated NBT test: a simple method suitable for antenatal diagnosis of chronic granulomatous disease.

    Science.gov (United States)

    Levinsky, R J; Harvey,