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Al-Bahry SN Al-Mashani BM Al-Ansari AS Elshafie AE Mahmoud IY 《Asian Pacific journal of tropical medicine》2013,6(9):718-722
ObjectiveTo screen for Escherichia coli (E. coli) resistant to tetracycline, followed by identification of tet efflux genes by polymerase chain reaction (PCR). In addition, detection of tetracycline residues in chicken livers and kidneys were conducted using high performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS-MS).MethodsStrains of E. coli were isolated from samples of chicken colon and screened for tetracycline resistance. Tetracycline genes conferring resistance (Tcr) were detected by polymerase chain reaction (PCR). Most of the isolates were resistant to tetracycline (97.9%).ResultsPCR analysis indicated that Tcr E. coli R-plasmids contained tet(A), tet(B) and a combination of both efflux genes. None of the isolates contained other efflux tet genes tet (C, D, E and Y). High performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS-MS), a sensitive technique, was used to detect residues of chlortetracycline (CTC), oxytetracycline (OTC), doxycycline (DC) in chicken livers and kidneys. The samples containing tetracycline residues were at 0.13-0.65 pg/μL levels.ConclusionsTetracycline and other antibiotics are commonly used in the poultry and meat production industry for prevention of microbial infections. Multiple antibiotic resistant bacteria in Oman have increased to alarming levels, threatening public health, domestic and may have adverse effect on environment. 相似文献
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PEGylation is a modification commonly used to increase the half-life of therapeutic proteins. The strategy for immunogenicity testing of these compounds should include methods to detect both anti-protein and anti-PEG antibodies. We previously reported a method for the detection of anti-PEG antibodies using ProterixBio’s (formerly BioScale) acoustic membrane microparticle (AMMP) technology. Our initial method development work showed the assay was capable of detecting antibodies in human serum with a sensitivity of 1 μg/mL with good reproducibility (CV?<?7%). Since the publication of this initial paper, additional experimentation was performed in an effort to validate the assay for support of clinical sample analysis. This additional data indicate that the method has high variability (CV%?>?20) and is unsuitable to support clinical sample analysis. 相似文献
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Michael W. Panas Jaimie D. Sixsmith KeriAnn White Birgit Korioth-Schmitz Shana T. Shields Brian T. Moy Sunhee Lee Joern E. Schmitz William R. Jacobs Jr. Steven A. Porcelli Barton F. Haynes Norman L. Letvin Geoffrey O. Gillard 《Infection and immunity》2014,82(12):5317-5326
Mycobacteria, the etiological agents of tuberculosis and leprosy, have coevolved with mammals for millions of years and have numerous ways of suppressing their host''s immune response. It has been suggested that mycobacteria may contain genes that reduce the host''s ability to elicit CD8+ T cell responses. We screened 3,290 mutant Mycobacterium bovis bacillus Calmette Guerin (BCG) strains to identify genes that decrease major histocompatibility complex (MHC) class I presentation of mycobacterium-encoded epitope peptides. Through our analysis, we identified 16 mutant BCG strains that generated increased transgene product-specific CD8+ T cell responses. The genes disrupted in these mutant strains had disparate predicted functions. Reconstruction of strains via targeted deletion of genes identified in the screen recapitulated the enhanced immunogenicity phenotype of the original mutant strains. When we introduced the simian immunodeficiency virus (SIV) gag gene into several of these novel BCG strains, we observed enhanced SIV Gag-specific CD8+ T cell responses in vivo. This study demonstrates that mycobacteria carry numerous genes that act to dampen CD8+ T cell responses and suggests that genetic modification of these genes may generate a novel group of recombinant BCG strains capable of serving as more effective and immunogenic vaccine vectors. 相似文献
77.
C.M. ODonnell N. Black K.C. McCourt M.E. McBrien M. Clarke C.C. Patterson B. Blackwood D.F. McAuley M.O. Shields 《British journal of anaesthesia》2019,122(1):120-130
Background
Perioperative studies of patients following hip fracture have large heterogeneity within their reported outcomes. This study aimed to develop a core outcome set for use in perioperative studies comparing the types of anaesthesia for hip fracture surgery.Methods
The consensus process consisted of a systematic review of the literature, three rounds of a Delphi survey, two consensus webinars, and face-to-face patient meetings.Results
The Delphi participants represented nine stakeholder groups. The numbers of participants completing Rounds 1–3 were 242, 186, and 169, respectively. Seventeen outcomes that met the predefined consensus criteria were considered at two consensus meetings. A final set of 10 core outcomes was agreed: mortality, time from injury to surgery, acute coronary syndrome, hypotension, acute kidney injury, delirium, pneumonia, orthogeriatric input, being out of bed at day 1, and pain.Conclusions
We generated a consensus-based set of core outcomes recommended for use in all perioperative trials evaluating the effects of anaesthesia for hip fracture surgery. An important next step is developing consensus-based consistency on how they should be measured.78.
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Kelly L Conrad Adeola R Davis Yuval Silberman Douglas J Sheffler Angela D Shields Sam A Saleh Namita Sen Heinrich JG Matthies Jonathan A Javitch Craig W Lindsley Danny G Winder 《Neuropsychopharmacology》2012,37(10):2253-2266
The alpha2 adrenergic receptor (α2-AR) antagonist yohimbine is a widely used tool for the study of anxiogenesis and stress-induced drug-seeking behavior. We previously demonstrated that yohimbine paradoxically depresses excitatory transmission in the bed nucleus of the stria terminalis (BNST), a region critical to the integration of stress and reward pathways, and produces an impairment of extinction of cocaine-conditioned place preference (cocaine-CPP) independent of α2-AR signaling. Recent studies show yohimbine-induced drug-seeking behavior is attenuated by orexin receptor 1 (OX1R) antagonists. Moreover, yohimbine-induced cocaine-seeking behavior is BNST-dependent. Here, we investigated yohimbine-orexin interactions. Our results demonstrate yohimbine-induced depression of excitatory transmission in the BNST is unaffected by alpha1-AR and corticotropin-releasing factor receptor-1 (CRFR1) antagonists, but is (1) blocked by OxR antagonists and (2) absent in brain slices from orexin knockout mice. Although the actions of yohimbine were not mimicked by the norepinephrine transporter blocker reboxetine, they were by exogenously applied orexin A. We find that, as with yohimbine, orexin A depression of excitatory transmission in BNST is OX1R–dependent. Finally, we find these ex vivo effects are paralleled in vivo, as yohimbine-induced impairment of cocaine-CPP extinction is blocked by a systemically administered OX1R antagonist. These data highlight a new mechanism for orexin on excitatory anxiety circuits and demonstrate that some of the actions of yohimbine may be directly dependent upon orexin signaling and independent of norepinephrine and CRF in the BNST. 相似文献
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