1.Preparation of recombinant firefly luciferase by a simple and rapid expression and purification method and its application in bacterial detection
Qin XIAO ; Hui CHEN ; Jinming LIN
Journal of Pharmaceutical Analysis 2010;22(2):97-101
A simple and rapid expression and purification method of recombinant firefly luciferase was developed for bacteria detection. A modified luciferase gene from North American firefly Photinus pyralis was cloned into pET28a expression vector and the recombinant protein was produced in Escherichia coli BL21. The recombinant luciferase, equipped with a polyhistidine affinity tag, was purified by immobilized metal ion affinity chromatography (IMAC). The approach generated an abundant expression and an efficient purification of a recombinant luciferase with final yield 1.995mg/L of cell culture. Experiments on the recombinant luciferase also showed that the relative light units (RUL) of the enzyme were 5.8×108, and the specific activity was 2.9×1010 RLU/mg. By applying adenosine triphosphate (ATP) bioluminescence to detection of the coin bacteria using the recombinant protein, the ATP content of bacteria was 9.48×10-16mol/mL, and was identical to the bacteria counts (4500CFU/mL) in order of magnitude. Taken together, our results provided a simple and efficacious method of the preparation of recombinant luciferase, which could be applied in the determination of bacteria via ATP bioluminescence.
2.Current research progress of choroidal metastasis
Lin-Hui, YUAN ; Xiao-Long, CHEN
International Eye Science 2016;16(7):1216-1220
Choroidal metastasis is one of the most common malignant tumors inside the eyes. It causes pain, hypopsia and some other related symptoms. It reduces the quality of the patients' life. It's significant for the patients to be detected and treated early, therefore they will have better vision and longer life. The treatments of choroidal metastasis are developing quickly. Both the vitreous cavity injection of targeted drug and gene therapy are hot topics of research. This paper summarizes the etiology, development, diagnosis and treatment of choroidal metastasis nowadays.
3.Changes in gene-expression profiling in kidney of rats with sepsis
Xiongjian XIAO ; Jiandong LIN ; Yi CAI ; Beilei ZHANG ; Hui LIN
Chinese Journal of Emergency Medicine 2010;19(9):909-915
Objective To investigate the gene-expression profile in kidney of rats during late sepsis (24hours) by using microarray technology in order to offer some clue to revealing the pathogenetic mechanism of sepsis at gene level. Method A total of 30 Wistar rats were selected and divided into model group and control group randomly(random number). The rats of control group were sham operated and the rats of model group received cecal ligature and puncture (CLP) operation. The biomarkers of renal function were assayed and the histopathological changes of kidney in rats were observed under transmission electron microscope 24 hours after operation. Gene chips containing 22 107 rat-genes cDNA were used to exmine gene-expression in kidney of septic rats to sieve the genes with different expressions with software. Data were analyzed by using SPSS version 11.0 software package.Statistical analyses of two independent samples carried out by using t -test. Results Compared with the control group, the levels of blood urea nitrogen (BUN) and creatinine (Cr) of sepsis group were higher (P < 0.01 ). The histopathological changes in kidney of rats demonstrated the establishment of sepsis model successful 24 hours later.Compared with the control group, there were 325 genes with differential expression in model group. Among the known-functional genes, there were 100 up-regulated and 64 down-regulated. Sorted by biological function, the genes were mainly related to metabolism, immunoresponse, cellular signal transduction, apoptosis, ion channel,growth factor and so on. Conclusions A sequence of genes expressed differentially in kidney of rats with late sepsis. Microarray technology played an important role in the research into sepsis mechanisms.
5.Preliminary application of voxel-based morphometry technique on brain changes in neuromyelitis optica
Hui XIAO ; Lin MA ; Ziqian CHEN ; Xin LOU ; Zhiye CHEN
Chinese Journal of Radiology 2011;45(4):336-340
Objective To investigate the changes of brain volumes in neuromyelitis optica (NMO)patients using voxel-based morphometry (VBM) method, and preliminarily explore the pattern of cerebral anatomical impairment. Methods Twenty-three clinically defined NMO patients and 15 gender and age matched healthy volunteers underwent 3-dimensional (3D) fast spoiled gradient echo (FSPGR) sequence scanning on 3.0 Tesla MR systen. Raw data was processed and analyzed using statistical parametric mapping (SPM) 5. Whole brain volumes included grey matter volume (GMV), white matter volume (WMV), total intracranial volume (TIV), grey matter fraction (GMF), white matter fraction (WMF),brain tissue fraction (BTF) and regional brain volumes between the two groups were compared by independent samples t-test and an Pearson were performed to compare the regional brain volumes and the ages. Results GMV of NMO group[(610. 2 ± 55.0) ml] was significantly decreased comparing to healthy control group[(657. 2 ± 36. 3) ml] (t = - 2. 915, P < 0. 05). The age of NMO patients [(40 ± 9) years old] showed negative correlation with GMF [(42. 5 ± 2. 6) %] (r = - 0. 673, P < 0. 05). Regional brain volume analysis showed decreased GMV in left insula and bilateral posterior cingutates in NMO patients,while decreased WMV was found in left frontal and left parietal white matter. Conclusion VBM could detect brain volume changes sensitively. Total grey matter volume in NMO patients was decreased comparing to HC group. Regional grey matter atrophy in NMO patients occurred in left insular and bilateral posterior cingutates, regional white matter atrophy occurred in left frontal and left parietal lobe.
7.Churg-Strauss syndrome in a child.
Yuan-yuan XIAO ; Lin MA ; Hui-min LI
Chinese Journal of Pediatrics 2010;48(7):545-546
Child
;
Churg-Strauss Syndrome
;
pathology
;
Female
;
Humans
9.Effects of chronic hypoxia on left and right ventricular function and the expression of cardiac TRPC channels in rats.
Hui-Qin CHEN ; Mo-Jun LIN ; Xiao-Ru LIU
Chinese Journal of Applied Physiology 2014;30(3):274-278
OBJECTIVETo explore the effects of chronic hypoxia on left and right ventricular function and the expression of cardiac transient receptor potential canonical (TRPC) channels in rats.
METHODSForty eight SD male rats were randomly divided into control group (CON) and chronic hypoxic pulmonary hypertension model group (CH) (n = 24). In CH group, rats were exposed in chronic hypoxia environment (10% +/- 0.2% O2) to induce myocardial hypertrophy. After 3 weeks, mean systemic arterial pressure (mSAP), right ventricular systolic pressure (RVSP), left ventricular systolic pressure (LVSP), left or right ventricular pressure maximum rate of rise (LV/RV + dp/dt(max)), left or right ventricular pressure maximum rate of descent (LV/RV-dp/dt(max)), right ventricular hypertrophy index (RVMI) and left ventricular hypertrophy index (LVMI) were measured. Left and right ventricular myocardium tissue sections were stained by HE and observed under light microscope. Real-time polymerase chain reaction (real-time-PCR) and Western blot were performed to detect the expression of TRPC subfamily.
RESULTSRVSP, RVMI, RV + dp/dt(max) and RV-dp/dt(max) were markedly elevated in CH group (P < 0.01) in comparison to CON group. LVMI was markedly reduced in CH group in comparison to CON group (P < 0.01). LVSP, LV + dp/dt(max) and LV- dp/dt(max) had no significant changes in CH group in comparison to CON group. Right ventricular myocardial cells of CH group became thick, the nuclei stained deeply, the shape of nuclei became not regularity. Left ventricular myocardial fibers did not change significantly. There was significant difference in the levels of mRNA and protein of TRPC1 between CON and CH groups.
CONCLUSIONFor three weeks exposed to chronic hypoxia induced right ventricular hypertrophy specifically, raised the mRNA and protein expression of TRPC1 on right ventricular myocardial cells . TRPC1 might be involved in the development of cardiac hypertrophy.
Animals ; Disease Models, Animal ; Hypertension, Pulmonary ; metabolism ; physiopathology ; Hypoxia ; metabolism ; physiopathology ; Male ; Rats ; Rats, Sprague-Dawley ; Transient Receptor Potential Channels ; metabolism ; Ventricular Function, Left ; physiology ; Ventricular Function, Right ; physiology