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Laura E.J. Peeters Siska Croubels Geertrui Rasschaert Hein Imberechts Els Daeseleire Jeroen Dewulf Marc Heyndrickx Patrick Butaye Freddy Haesebrouck Annemieke Smet 《International journal of antimicrobial agents》2018,51(1):123-127
Pig feed may contain various levels of antimicrobial residues due to cross-contamination. A previous study showed that a 3% carry-over level of doxycycline (DOX) in the feed results in porcine faecal concentrations of approximately 4?mg/L.The aim of this study was to determine the effect of residual DOX concentrations (1 and 4?mg/L) in vitro on selection of DOX–resistant porcine commensal Escherichia coli and transfer of their resistance plasmids.Three different DOX–resistant porcine commensal E. coli strains and their plasmids were characterised. These strains were each brought in competition with a susceptible strain in a medium containing 0, 1 and 4?mg/L DOX. Resistant bacteria, susceptible bacteria and transconjugants were enumerated after 24?h and 48?h.The tet(A)–carrying plasmids showed genetic backbones that are also present among human E. coli isolates. Ratios of resistant to susceptible bacteria were significantly higher at 1 and 4?mg/L DOX compared with the blank control, but there was no significant difference between 1 and 4?mg/L. Plasmid transfer frequencies were affected by 1 or 4?mg/L DOX in the medium for only one of the resistance plasmids.In conclusion, DOX concentrations of 1 and 4?mg/L can select for resistant E. coli in vitro. Further research is needed to determine the effect of these concentrations in the complex environment of the porcine intestinal microbiota. 相似文献
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Silvana B. Marchioro Rubén Del Pozo Sácristan Annelies Michiels Freddy Haesebrouck Fabricio R. Conceição Odir A. Dellagostin Dominiek Maes 《Vaccine》2014
A recombinant chimaeric protein containing three Mycoplasma hyopneumoniae antigens (C-terminal portion of P97, heat shock protein P42, and NrdF) fused to an adjuvant, the B subunit of heat-labile enterotoxin of Escherichia coli (LTB), was used to immunize pigs against enzootic pneumonia. The systemic and local immune responses, as well as the efficacy of the chimaeric protein in inducing protection against experimental M. hyopneumoniae infection were evaluated. In total, 60 male piglets, purchased from a M. hyopneumoniae-free herd, at 4 weeks of age were randomly allocated to six different experimental groups of 10 animals each: recombinant chimaeric protein by intramuscular (IM) (1) or intranasal (IN) (2) administration, commercial bacterin by IM administration (3), and the adjuvant LTB by IM (4, control group A) or IN (5, control group B) administration. All groups were immunized at 24 and 38 days of age and challenged at 52 days of age. The sixth group that was not challenged was used as the negative control (IN [n = 5] or IM [n = 5] administration of the LTB adjuvant). Compared with the non-challenged group, administration of the chimaeric protein induced significant (P < 0.05) IgG and IgA responses against all individual antigens present in the chimaera, but it could not confer a significant protection against M. hyopneumoniae infection in pigs. This lack of effectiveness points towards the need for further studies to improve the efficacy of this subunit-based vaccine approach. 相似文献
35.
Necrotic enteritis in broilers is caused by Clostridium perfringens type A strains that produce the NetB toxin. Necrotic enteritis is one of the gastrointestinal diseases in poultry that has gained worldwide importance during the last decade due to efforts to improve broiler performance. Prevention strategies include avoiding predisposing factors, such as coccidiosis, and in-feed supplementation with a variety of feed additives. However, vaccination with modified toxin or other secreted immunogenic proteins seems a logical preventive tool for protection against a toxin-producing bacterium. Formalin-inactivated crude supernatant has been used initially for vaccination. Several studies have been carried out recently to identify the most important immunogenic and protective proteins that can be used for vaccination. These include the NetB toxin, as well as a number of other proteins. There is evidence that immunization with single proteins is not protective against severe challenge and that combinations of different antigens are needed. Most published studies have used multiple dosage vaccination regimens that are not relevant for practical use in the broiler industry. Single vaccination regimens for 1-day-old chicks appear to be non-protective. This review describes the history of vaccination strategies against necrotic enteritis in broilers and gives an update on future vaccination strategies that are applicable in the field. These may include breeder hen vaccination, in ovo vaccination and live attenuated vectors to be used in feed or in drinking water. 相似文献
36.
Mory Keita Mahamoud Sama Cherif Billy Sivahera Samuel T. Boland Freddy Banza-Mutoka Mamadou Kourouma Alseny Modet Camara Youssouf Sidibe Jean Paul Kimenyi Lamine Diassy Angelo Loua Ibrahima Sory Fofana Youba Kandako Dobo Onivogui Enogo Koivogui Tamba Jacques Millimono Fode Diakite Mamadou Balde Bienvenu Houndjo Ngoy Nsenga Ambrose Talisuna Alexandre Delamou Olivia Keiser Georges Alfred Ki-Zerbo Abdou Salam Gueye 《The American journal of tropical medicine and hygiene》2022,106(4):1094
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Mendizábal-Cabrera Renata Pérez Isabel Montekio Víctor Becerril Pérez Freddy Durán Erick Trueba Mei L. 《贫困所致传染病(英文)》2021,10(3):14-25
Background::Cutaneous leishmaniasis (CL), endemic in Guatemala, mostly affects poor people living in the northern region. A national control program that includ... 相似文献
38.
Luis Carlos Álvarez-Perdomo Paola Andrea Pedraza-Atahualpa Álvaro Eduardo Mondragón-Cardona Freddy Escobar-Montealegre Carlos Eduardo Jiménez-Canizales 《The Egyptian Rheumatologist》2018,40(3):213-216
Introduction
Systemic lupus erythematosus (SLE) is an autoimmune disease with multiple systemic manifestations. The disease itself typically causes only 2–30% of SLE-associated gastrointestinal conditions.Case report
We present the case of a 16-year-old male with history of SLE diagnosed 5 months prior to admission. Patient was non-compliant to medical treatment. He presented with 20?days of cough, mucopurulent and blood-tinged sputum, progressive shortness-of-breath and abdominal bloating. Patient was found to have multiple organ dysfunction due to an active lupus flare that developed during hospitalization, and required treatment with high doses of corticosteroids and close observation in an intensive care unit. Despite initial improvement of symptoms, he continued with abdominal pain, bloating, abolished bowel sounds and poor food intake. An abdominal X-ray showed signs of intestinal obstruction, establishing the diagnosis of intestinal pseudo-obstruction (IpsO). Patient then displayed a marked improvement of his gastrointestinal condition following treatment with 400?mg/kg/day of intravenous immunoglobulin (IVIgG) for 5?days.Conclusion
Intestinal pseudo-obstruction is an unusual clinical manifestation of SLE and may represent a diagnostic challenge. We underscore the importance of a prompt and precise recognition of this condition, which is likely to have a positive impact on clinical outcomes. IpsO is caused by a non-mechanical obstructive bowel injury. Evidence points towards to the use of IgG and steroid for five days as the mainstay of therapy for patients with IpsO. 相似文献39.
Ian De Silva Mervyn G. Thomas Amy-lee Shirodkar Helen J. Kuht Jae Yee Ku Ritu Chaturvedi Freddy Beer Radhika Patel Romeela Rana-Rahman Sarah Anderson Polly Dickerson Francine Walsh Ben While Lucy Clarke Dilani Siriwardena Felipe Dhawahir-Scala BEECS Study Group John Buchan Seema Verma 《Eye (London, England)》2022,36(12):2304
Background/ObjectivesTo characterise the patterns of presentation and diagnostic frequencies in Hospital Emergency Eye Care Services (HEECS) across 13 hospitals in England.MethodsRetrospective, cross-sectional, observational multi-centre (n = 13) study to assess HEECS attendances over a 28-day study period. Data derived included: number of consecutive attendances, patient demographics and diagnoses. Age and gender variations, the impact of day of the week on attendance patterns, diagnostic frequencies and estimates of the annual incidence and attendance rates were evaluated.ResultsA total of 17,667 patient (mean ± standard deviation age = 49.6 ± 21.8 years) attendances were identified with an estimated HEECS annual new attendance rate of 31.0 per 1,000 population. Significantly more females (53%) than males (47%) attended HEECS (p < 0.001). Female attendances were 13% higher in those ≥50 years of age. Weekends were associated with a significant reduction in attendances compared to weekdays (χ2 = 6.94, p < 0.001). Among weekdays, Mondays and Fridays were associated with significantly higher attendances compared with midweek (χ2 = 2.20, p = 0.032). Presenting pathologies involving the external eye, cornea and conjunctiva accounted for 28.6% of the caseload.ConclusionThis is the largest multicentre study assessing attendance patterns in HEECS in England. We have, for the first time, observed a “weekend effect” in relation to attendance to HEECS. Differences in health-seeking behaviour and lack of awareness of HEECS weekend services may be partly attributed to the differences observed. Our findings, along with the type of presentations, have the potential to guide commissioners with future planning of HEECS.Subject terms: Epidemiology, Epidemiology 相似文献
40.