RESUMO
Immunomagnetic separation (IMS) was coupled with fluorescent microspheres lateral flow assay (FM-LFA) for rapid detection of S.choleraesuis in this study.The target bacteria were firstly enriched from sample by immunomagnetic beads (IMBs),then eluted by heat treatment and detected by fluorescent microspheres lateral flow test strip.The IMBs was labeled with 30 μg/mg antibody,and the capture efficiency was greater than 90％ against 102-106 CFU/mL of S.choleraesuis with great specificity.The immunofluorescent microspheres were prepared by coupling 300 μg of 11 D8-D4 monoclonal antibody with 1 mg of fluorescent microspheres at pH 6.Monoclonal antibody 5F11-B11 (2.0 mg/mL) and donkey anti-mouse IgG (1.0 mg/mL) were sprayed on nitrocellulose membrane as test line and control line,respectively.The FM-LFA based on IMS was used to detect S.choleraesuis in PBS and milk.The limits of detection in PBS buffer and milk were 1.5×105 CFU/mL and 7.6×105 CFU/mL respectively,which were 10 and 200 times lower than that of traditional fluorescent microspheres lateral flow assay,respectively.The results showed that the method,which could enrich S.choleraesuis in milk effectively,could avoid matrix interference and improve the detection sensitivity,thus had a good application prospect.
RESUMO
Aim To establish the standards for evaluation of microcirculation in a rat hind limb ischemia model.Methods Rats were subjected to unilateral femoral artery ligation.After 4 weeks,the regional blood flow in skeletal muscles was measured by fluorescent microsphere assay.Formation of collateral vessels was determined by microangiography.Capillary density was examined by immunostaining for CD34.Results In ischemic limbs,regional blood flow decreased significantly,some collateral vessels formed with typical "corkscrew" appearance,and histological analysis showed lower capillary density.Conclusion Quantitative assessment of microcirculation in a hind limb ischemia model is established.