Quantification of antigen of Mycoplasma capricolum subsp. capripneumoniae by optical assay / 生物工程学报

Mycoplasma capricolum subsp. capripneumoniae (Mccp) is the cause of contagious caprine pleuropneumonia (CCPP) in goats. Inactivated vaccines and capsular polysaccharide (CPS) indirect hemagglutination reagents are available for prevention and serological detection, but high culture costs and complex antigen quantification have been plagued by production staff. In order to solve these problems in production practice, a sugar fermentation medium with an initial pH value of 7.8, which could improve the production of two antigens simultaneously, was screened out by changing the initial pH value based on previous Mccp metabolomics analysis. Since phenol red can be identified by UV absorption spectrum and cetyltrimethylammonium bromide (CTAB) can bind to anionic capsular polysaccharide, a UV spectrum measurement method for analyzing the culture stage reached by Mccp and a CTAB precipitation test for relative quantification of capsular polysaccharide antigen content in the fermentation broth were established. The UV spectrum observation method can guide the production of Mccp according to the growth curve of Mccp, which greatly reduces the monitoring time of the traditional CCU method and improves the accuracy of the original eye-observation method. The established CTAB precipitation test can complete the monitoring of CPS content within 5 hours, which greatly reduces the time required compared with the traditional differential technique, and its accuracy was verified by the phenol-sulfuric acid method. The optimized culture medium and the two correlation comparison methods established in this study can effectively reduce the production cost of Mccp and improve the production efficiency. The two assays have been used in the research at our laboratory, which provides experimental data for further improvement of the production process of CCPP inactivated vaccine and capsular polysaccharide as well as rapid quantification.

The application research of low-dose spectral CT imaging combined with ASIR reconstruction in different- ing peripheral lung cancer from inflammatory mass / 实用医学杂志

Objective To evaluate the value of low-dose spectral CT imaging combined with ASIR recon-struction in differenting peripheral lung cancer from inflammatory mass. Methods We retrospectively analyzed the imaging data of 147 cases with 165 pulmonary nodules or masses underwent enhanced CT scans with spectral imag-ing mode from June 2015 to May 2016. Spectral curves,normalized slope rates,iodine-water concentration were measured on the lesions in arteral phase images. The differences of the spectral characteristic parameters were eval-uated statistically by indepengdent samples t test. Results Among 165 pulmonary nodules or masses,including 68 inflammatory mass and 97 peripheral lung cancer. In the arterial phase,the iodine concentration,water concentra-tion and normalized spectral curves rates of peripheral lung cancer were 10.93 ± 5.12,1033.96 ± 9.74,0.998 ± 0.66,which was obviously higher than those in inflammatory mass in 5.29 ± 0.96,1028.85 ± 9.31,0.620 ± 0.16. There were significant difference between peripheral lung cancer and inflammatory mass(0.000 ,0.008 ,0.001 in P values). Conclusion The iodine concentration,water concentration and normalized spectral curves rates has high value for differential diagnosis of peripheral pung cancer and pneumonia mass in the arterial phase using low-dose spectral CT imaging combined with ASIR reconstruction.

Functional MRI observation of the aging selective degradation mode of large-scale brain functional networks / 中华老年医学杂志

Objective To investigate the degradation characteristics of the large-scale brain functional networks during aging by functional magnetic resonance imaging measurement and explore its intrinsic mechanism.Methods 40 healthy subjects including 20 elderly persons [mean aged(72.4 ±4.6)years] and 18 young persons [mean aged(23.9± 1.8) years] were enrolled in this study.All subjects underwent functional MRI scanning at blood oxygenation level-dependent contrast resting state.Four canonical resting-state networks,including the default mode network (DMN),dorsal attention network (DAN),executive control network (ECN),salience network,and visual network,were extracted by the seed zone and double regression methods.The functional connectivities in these canonical networks were compared between the young and elderly persons.Results Compared with young persons,the elderly showed the distinct and disruptive alterations in the large-scale aging-related resting brain networks.The impairment of ECN was the most serious,followed by the impairment of DAN.The salience networks and DMN showed relatively limited functional connectivity disruption.The networks associated to higher-order brain functions were impaired,while the visual network,which served as a network related to low-order brain functions,had no significant change.Conclusions The aged brain in healthy subjects is characterized by organized change in networks,and the selective impairments of large-scale brain networks were more significant in the networks associated to higher-order brain functions as compared with the networks related to low-order brain functions.

Magnetic resonance imaging and radiological findings of familial sacral agenesis: a report of 6 cases / 中华全科医师杂志

The clinical characteristics and radiological data of 6 cases of sacral agenesis in one single family were analyzed and a literature review was performed.On magnetic resonance imaging (MRI),all of them presented with a partial absence of sacral vertebra,including associations with lumbar abnormalities (n =2) and sacral agenesis (n =2).One case presented with fourth/fifth lumbar vertebra bone fusion and fifth lumbar/first sacral vertebra bone fusion.On radiology,4 cases had concurrent scoliosis.None of them had tethered cord,diastematomyelia or meningocele.The understanding of sacral agenesis may be improved after reviewing and summarizing clinical features and radiological findings.