Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Escherichia coli lipopolysaccharide B was instilled through the lactiferous duct of cows to induce acute mastitis. Hemolytic complement (C) activity and C3 concentrations were determined in blood serum and in renninprecipitated whey before, and at certain times after, mastitis was induced. Hemolytic complement activity was detected in the whey only during the first 36 hours after endotoxin was instilled, whereas activity was not seen before and 48 or more hours after the endotoxin was given. The maximum titer as measured with the guinea pig RBC/bovine natural antibody system was 1:64. The C3 concentrations in normal whey (before installation of endotoxin), measured by radial immunodiffusion, were between 1% and 4% of the base-line blood serum values (pool from healthy cows). The whey concentration of C3 increased (to 5% to 18%) during the first 8 hours of mastitis. However, at 72 hours, the whey values were back to preinstillation concentrations in all quarters.
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PMID:Hemolytic complement titers and complement C3 levels in endotoxin-induced mastitis. 635 13

A method has been developed to assay the relative penetrability to a solute of the papillary duct (streak canal) of the bovine teat. Escherichia coli lipopolysaccharide endotoxin (1.0 microgram in 2.5 microliter of sterile distilled water) was implanted at a depth of 3 mm from the distal end (papillary orifice) of the papillary duct. If penetration by the irritant occurred after any one of 5 successive daily implantations, the inflammatory response of the mammary gland was detected by a precipitous increase (by at least 15 mm) in the Wisconsin mastitis test score of quarter foremilk samples, and the test was scored as positive. Results of the penetrability assay were highly repeatable among quarters of certain cows. Cows differed as to the pattern of penetrability of their papillary ducts, with about half of 70 tested cows scoring 4 positive or 4 negative.
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PMID:Assay of penetrability of bovine papillary duct implanted with Escherichia coli endotoxin. 703 34

The role of interleukin 1 (IL-1) as an inflammatory mediator during mastitis and the therapeutic effect of recombinant human IL-1 receptor antagonist (IL-1ra) for bovine mastitis was studied. Cows were intramammarily infused with lipopolysaccharide (25 micrograms) in 1 mammary gland. Half the cows also received infusions of 5 mg of IL-1ra into the same mammary gland just prior to endotoxin infusion and 4, 8, and 12 hours later. After endotoxin infusion, tumor necrosis factor and high IL-1 bioactivity were detected in whey from infused glands. Vascular permeability changes and neutrophil accumulation in milk paralleled the appearance of cytokines. A systemic reaction, characterized by pyrexia and an increase in blood cortisol concentration, also were observed. Milk yield was inhibited and milk composition was altered in infused and noninfused glands. The increase in IL-1 bioactivity in milk after endotoxin infusion was almost completely prevented in glands receiving IL-1ra. However, IL-1ra had no effect on local inflammation, systemic reaction, or impairment in productive performance. These results indicate that IL-1 does not mediate its effect within the milk compartment, and suggest either that IL-1 is not critical to the mastitic response or that intramammary infusion of IL-1ra does not place the antagonist where IL-1 interacts with its receptor.
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PMID:Administration of recombinant human interleukin 1 receptor antagonist during endotoxin-induced mastitis in cows. 777 98

The family Pasteurellaceae Pohl contains Gram-negative, facultatively anaerobic and fermentative bacteria of the genera Pasteurella, Haemophilus, and Actinobacillus. Approximately 20 different species of the genus Pasteurella have been identified using phenotypic and genetic analyses. Of these species, P. multocida and P. haemolytica are the most prominent pathogens in domestic animals causing severe diseases and major economic losses in the cattle, swine, sheep, and poultry industries. Mechanisms of immunity to these bacteria have been difficult to determine, and efficacious vaccines have been a challenge to develop and evaluate. Pasteurella multocida of serogroups A and D are mainly responsible for disease in North American poultry and pigs and to a lesser extent in cattle. Fowl cholera in chickens and turkeys is caused by various serotypes of P. multocida serogroup A and characterized by acute septicemia and fibrinous pneumonia or chronic fibrinopurulent inflammation of various tissues. Current biologicals in use are live P. multocida vaccines and bacterins. Potency tests for avian P. multocida biologicals are a bacterial colony count for vaccines and vaccination and challenge of birds for bacterins. Somatic antigens, particularly lipopolysaccharide (LPS), appear to be of major importance in immunity. In North American cattle, P. multocida serogroup A is associated mainly with bronchopneumonia (enzootic pneumonia) in young calves; however, it is occasionally isolated from fibrinous pleuropneumonia of feedlot cattle (shipping fever). Biologicals currently available are modified-live vaccines and bacterins. The potency test for vaccines is bacterial colony counts. The test for bacterin potency is vaccination and challenge of mice. Important immunogens have not been well characterized for P. multocida infection in cattle. In swine, P. multocida infection is sometimes associated with pneumonia; however, its major importance is in atrophic rhinitis. A protein toxin (dermonecrotic toxin), produced by toxigenic strains of P. multocida types A and D, and concurrent infection with Bordetella bronchiseptica appear to be the major factors in development of atrophic rhinitis. Currently available biologicals are bacterins and inactivated toxins (toxoids). The toxin appears to be the major immunogen for preventing atrophic rhinitis. There are, however, no standardized requirements for potency testing of P. multocida type D toxoid. Various serotypes of P. haemolytica biotype A are responsible for severe fibrinous pleuropneumonia of cattle and sheep, occasionally septicemia of lambs, and mastitis in ewes. Several serotypes of P. haemolytica biotype T are isolated from acute septicemia of lambs. The currently available P. haemolytica biologicals are modified-live vaccines, bacterins, bacterial surface extracts, and culture supernates that contain an exotoxin (leukotoxin).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Immunogens of Pasteurella. 811 91

Ibuprofen treatment was compared with saline solution treatment in an endotoxin-induced experimental model of bovine mastitis. Acute mastitis was induced in healthy lactating Holstein cows (n = 12) by intramammary inoculation of 1 mg of Escherichia coli 026:B6 lipopolysaccharide in a single quarter per cow. Cows were assigned at random to ibuprofen (25 mg/kg of body weight, IV, n = 6) or 0.9% sodium chloride solution control (1.25 ml/kg, IV, n = 6) treatment groups. Ibuprofen or saline solution was administered once, 2 hours after endotoxin administration. The clinical course of endotoxin-induced mastitis and hematologic, clinical biochemical, and plasma mineral changes were monitored and compared between ibuprofen-treated and control cows. Clinical monitoring and blood sample collection were performed at 0, 2, 4, 6, 8, 12, 24, 48, 96, and 192 hours after endotoxin challenge. Rectal temperature and heart and respiratory rates were significantly (P < or = 0.05) increased in saline treated cows, compared with cows treated with ibuprofen. Blood eosinophil count and serum phosphorus, sodium, and total carbon dioxide concentrations were significantly (P < or = 0.05) decreased in saline-treated cows, compared with cows treated with ibuprofen. Ibuprofen treatment did not significantly change ruminations per minute, electrical conductivity of milk, quarter size, or quarter inflammation. The remaining hematologic, serum biochemical, plasma mineral, and coagulation values also were not changed significantly in response to ibuprofen treatment. Untoward effects attributed to ibuprofen administration were not observed. These results indicate that ibuprofen may provide empiric relief of clinical signs of coliform-induced mastitis.
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PMID:Ibuprofen treatment of endotoxin-induced mastitis in cows. 836 9

A description of new commercial and experimental vaccines for viral and bacterial diseases of cattle can be broadly divided into those used for both beef and dairy cows and those used predominantly in dairy cattle. For both types of cattle, newer and experimental vaccines are directed against several of the important viral (e.g., bovine herpesvirus 1, bovine viral diarrhea virus, bovine respiratory syncytial virus, parainfluenza type 3, and foot-and-mouth disease virus) and bacterial pathogens (e.g., Pasteurella spp., Haemophilus somnus). The viral vaccines include gene-deleted, modified live, subunit, and peptide antigens. Newer bacterial vaccines, particularly those for Pasteurella spp., are composed of either modified-live vaccines or bacterins supplemented with toxoid or surface antigens. Haemophilus somnus vaccine research has concentrated mainly on defining unique surface antigens. Novel dairy cow vaccines would include the lipopolysaccharide-core (J5) antigen approach, which has been used for successful immunization against coliform mastitis. Core antigen vaccines also have reduced calf mortality from Gram-negative pathogens. Staphylococcal mastitis vaccines that contain capsular antigens, toxoids, or the staphylococcal fibronectin receptor are of active research interest. Vaccines against mastitis induced by Streptococcus agalactiae and Streptococcus uberis also are areas of intensive research. Delivery of multiple subunit antigens with optimal immune response induction has led to the investigation of attenuated heterologous viral and bacterial expression vectors such as bovine herpesvirus 1, vaccinia, and Salmonella spp. This discussion also demonstrates that molecular biology is being used to advance bovine vaccine technology.
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PMID:Recent advances in bovine vaccine technology. 840 72

The role of interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor alpha during endotoxin-induced mastitis in cows was characterized. Six cows had 10 micrograms of Escherichia coli lipopolysaccharide infused into 1 mammary gland. Three other cows served as nontreated controls. Within 1.5 to 2.5 hours after infusion, endotoxin caused obvious edema of the mammary gland and increased serum albumin concentration in milk of infused glands 6 times. Milk somatic cell count began to increase 3 to 5 hours after infusion in all treated glands. At 7 hours after infusion, somatic cell counts were increased > 10 times, compared with counts in milk from control cows. Pyrexia of > 1 C developed in only 1 cow, but all treated cows had serum cortisol concentrations > 50 ng/ml in response to endotoxin treatment. High concentrations of IL-1 (10 to 600 U/ml) and IL-6 (2 to 22 U/ml) were detected in milk of infused glands beginning 2.5 to 4 hours after infusion. Endotoxin did not induce detectable amounts of tumor necrosis factor activity in milk or serum. Swelling and mammary gland permeability changes preceded any detectable increase in IL-1 and IL-6 activity, indicating that these clinical signs of inflammation were not mediated by these cytokines. Systemic responses and the leukocytic influx into endotoxin-infused glands developed after or concurrently with initial increases in IL-1 and IL-6 activities in milk. These results suggested that IL-1 and IL-6 may have a role in mammary gland defenses and in the pathophysiologic changes during endotoxin-induced mastitis.
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PMID:Cytokine production during endotoxin-induced mastitis in lactating dairy cows. 842 76

We investigated a possible mechanism by which immunization against core and lipid A determinants of lipopolysaccharide reduced clinical cases of mastitis and symptoms commonly associated with heterologous Gram-negative IMI. The IgG fraction of sera from cows immunized with either Escherichia coli J5 bacterin, E. coli J5 lipopolysaccharide conjugate vaccine, or unimmunized controls was purified by precipitation with caprylic acid and ammonium sulfate. The degree of IgG crossreactivity with Gram-negative bacteria that were isolated from clinical quarters was greater than that with Gram-positive isolates of Staphylococcus aureus. The highest magnitude of crossreactivity was against smooth strain E. coli isolates, followed by heterologous species of Enterobacter, Serratia, and Klebsiella isolates. Serum IgG from cows immunized with conjugate was highly crossreactive to E. coli J5, E. coli O111:B4, Serratia marcescens, Klebsiella pneumoniae, and Salmonella typhimurium lipopolysaccharides. The magnitude of antibody crossreactivity with lipopolysaccharides coincided with the ability of IgG to suppress the mitogenic effect of lipopolysaccharides on bovine lymphocytes.
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PMID:Antigenic crossreactivity and lipopolysaccharide neutralization properties of bovine immunoglobulin G. 867 57

This study examined the production of tumor necrosis factor (TNF-alpha) by mononuclear cells isolated from peripheral blood and supramammary lymph nodes of periparturient and mid to late lactating dairy cows. Monocyte-enriched cell populations were stimulated with lipopolysaccharide (LPS) and analyzed for TNF-alpha concentrations. Flow cytometric analysis was performed to determine the frequencies of relevant cell populations. Isolated mononuclear cells from periparturient dairy cows produced significantly higher levels of TNF-alpha than mid to late lactating dairy cows regardless of tissue location. A corresponding increase in the frequency of monocytes also was observed in tissue samples obtained from periparturient animals. The higher proportion of monocytes capable of producing TNF-alpha in the periparturient dairy cow may account for the increased levels of this potent mediator. Within the periparturient period, peripheral blood mononuclear cells were found to produce significantly less TNF-alpha than cells isolated from mammary lymph nodes. However, flow cytometric analysis revealed similar monocyte concentrations in both the peripheral blood and mammary lymph node. This indicates that the differences in cytokine production may be due to variations in monocyte activation state with respect to tissue location. It is possible that greater potential to produce TNF-alpha during the periparturient period may contribute to the severe acute phase response of the mammary gland to coliform infections during this time. Limiting TNF-alpha production by monocytes, particularly within the mammary gland, may reduce the severity of clinical coliform mastitis in periparturient dairy cattle.
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PMID:Enhanced production of bovine tumor necrosis factor-alpha during the periparturient period. 874

A cross-sectional study was performed on the occurrence of IgG antibodies to lipid A of the Gram-negative bacterial lipopolysaccharide (LPS, endotoxin) on serum of 2272 cattle distributed on 19 Danish dairy herds. The relationship between the concentration of antibodies to lipid A (ALI) and age, herd, pregnancy rate and occurrence of mastitis, bovine virus diarrhoea (BVD), reproductive and digestive disorders, diarrhoea, pneumonia, foot disorders, various infections and traumatic udder lesions was investigated. ALI generally was low in calves and increased during their first 1.5 years of life to a steady state, which could be altered by the occurrence of disease. There were significant differences in the mean ALI among the herds (P < 0.001). High ALI was associated with a low herd pregnancy rate, to preceding occurrence of mastitis (P < 0.048), BVD (P < 0.01), reproduction diseases (P < 0.041) and digestion disorders (P < 0.064) in animals older than 2 years. The calf mortality rate was not associated to ALI and there was no correlation between the ALI in calves and their dams. The occurrence of high ALI levels on a herd basis may be an indication of increased challenge or enhanced immunological defense to Gram-negative bacteria or endotoxin.
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PMID:Prevalence of antibodies to lipid A in Danish cattle. 877 1


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