ABSTRACT
To describe a novel particles surface display system which is consisted of gram-positive enhancer matrix (GEM) particles and anchor proteins for bacteria-like particles vaccines, we treated Lactobacillus rhamnosus GG bacteria with 10% heated-TCA for preparing GEM particles, and then identified the harvested GEM particles by electron microscopy, RT-PCR and SDS-PAGE. Meanwhile, Escherichia coli was induced to express hybrid proteins PA3-EGFP and P60-EGFP, and GEM particles were incubated with them. Then binding of anchor proteins were determined by Western blotting, transmission electron microscopy, fluorescence microscopy and spectrofluorometry. GEM particles preserved original size and shape, and proteins and DNA contents of GEM particles were released substantially. The two anchor proteins both had efficiently immobilized on the surface of GEM. GEM particles that were bounded by anchor proteins were brushy. The fluorescence of GEM particles anchoring PA3 was slightly brighter than P60, but the difference was not significant (P>0.05). GEM particles prepared from L. rhamnosus GG have a good binding efficiency with anchor proteins PA3-EGFP and P60-EGFP. Therefore, this novel foreign protein surface display system could be used for bacteria-like particle vaccines.
ABSTRACT
Objective To detect quantitatively AKAP12 methylation and evaluate its clinical significance in peripheral blood in colorectal cancer. Methods MS-HRM technology was used to detect quantitatively AKAP12 methylation in peripheral blood from 80 colorectal cancer patients and 20 healthy volunteers. They also validated the reproducibility and compared with MSP. Results Thirty-eight of the 80 colorectal cancer samples (47. 5% ) were found to be methylated at the AKAP12 promoter region by MS-HRM (the methylation levels of 24 cancer samples ranged between 1 % and 20% , the methylation levels of 12 cancer samples ranged between 20% and 60% , the methylation levels of 2 cancer samples ranged between 60% and 100% ). The methylation levels of 2 health samples were less than 10% . They also compared the results generated by MS-HRM with a traditional MSP assay. The AKAP12 MS-HRM assay was able to reproducibly detect 1% AKAP12 methylated DNA, whereas the MSP method was unable to detect less than 10% methylation. No significant correlation was observed between the AKAP12 methylation levels and patients' age and gender. However, AKAP12 methylation was significantly higher in DNA from colorectal cancer patients with high Dukes stage and differentiation (x2 =5. 93 or 8. 41, P = 0.01). Conclusions The authors demonstrate here for the first time, the utility of quantitative AKAP12 MS-HRM analysis of promoter methylation in peripheral blood samples. AKAP12 MS-HRM quantitative methods have many promising applications in the detection of colorectal cancer.
ABSTRACT
Objective To explore the differences of clinical features and relationship between aplastic anemia paroxysmal nocturnal hemoglobinuria syndrome(AA PNH syndrome)and typical paroxysmal nocturnal hemoglobinuria(t PNH).Methods A case control study on the discrepancies of clinical and laboratory features between patients with AA PNH syndrome and t PNH was carried out.Results Compared with t PNH,AA PNH syndrome showed following features:①Lower frequencies of venous thrombosis,jaundice and enlarged liver or spleen.②Higher percentages of pancytopenia and bone marrow hypoplasia.③Lower percentages of positive hemolysis tests.The percentages of CD55 and CD59 of peripheral blood cells were not significantly different in most cases of both groups.④Immunoglobulins and subgroups of T lymphocytes were normal in cases of both groups.⑤Adrenocortical hormone was effective in cases of both groups.Conclusion AA PNH syndrome shares a same pathophysiology with t PNH;CD55 and CD59 tests can improve the diagnosis of AA PNH syndrome.