1.Highly Sensitive and Label-free Fluorescence Detection of DNA Based on Structure Switch of Hairpin Probe DNA to G-Quadruplex-based DNAzyme
Luna SONG ; Yonghua ZHANG ; Hongyan BO ; Qiang GAO
Chinese Journal of Analytical Chemistry 2015;(9):1402-1407
A label-free fluorescent assay for highly sensitive detection of DNA was developed based on structure switch of hairpin DNA probe to a G-quadruplex-based DNAzyme triggered by target DNA. The hairpin DNA probe includes sequences that correspond to the base sequence of the G-quadruplex and to the sequence complementary to the target DNA, respectively. The hairpin structure of the probe DNA is
energetically favored over the G-quadruplex structure in the absence of target DNA, resulting in the protection of the G-quadruplex in an inactive hairpin configuration. The hybridization of target DNA to the loop domain opens the stem of the hairpin, resulting in the self-assembly of the uncaged G-quadruplex structure, which acts as a DNAzymatic label for the signal production and amplification in the presence of hemin. The peroxidase-like DNAzyme oxidizes non-fluoresecnt 10-acetyl-3,7-Dihydroxypenoxa-zin (ADHP) to the florescent product by H2 O2 , giving rise to fluorescence emission. This allowed the utilization of the H2 O2-ADHP fluorescent system for quantitative analysis of DNA. The experimental conditions were optimized as:pH 8. 0, 10 mmol/L K+, 0. 2 μmol/L Hemin, 50 μmol/L ADHP. The assay showed a linear relationship toward target DNA concentration in the range of 5. 0 pmol/L-1. 0 nmol/L, with a limit of detection of 3. 0 pmol/L (S/N=3). The assay exhibited good selectivity against single-base mismatched DNA.
2.Abnormal Toxicity Test and Study on the in vitro Hemolytic Reaction of Gluconate Enoxacin Injection
Luna WENG ; Jing SONG ; Ying HONG ; Ying ZHANG
China Pharmacy 2017;28(31):4398-4400
OBJECTIVE:To conduct the abnormal toxicity test and study on the in vitro hemolytic reaction of Gluconate enoxa-cin injection,and provide reference for its safe use. METHODS:According to"Test for Abnormal Toxicity"in Chinese Pharmaco-poeia(2015 edition,Vol.Ⅱ),half lethal dose(LD50)of Gluconate enoxacin injection and setting of abnormal toxicity limit were carried out in mice. According to"Test for Haemolysis and Agglomeration"in Chinese Pharmacopoeia (2015 edition,Vol.Ⅱ), study for the in vitro hemolytic and agglomeration reaction was carried out in rabbits. RESULTS:The LD50 of Gluconate enoxacin injection for mice was 248.9 mg/kg;the setting limit of abnormal toxicity test was 28.4 mg/kg,and the results derived from the test using this limit met requirements. The haemolysis and agglomeration results derived from the test using clinical maximum con-centration(0.2 g/100 mL)met requirements. CONCLUSIONS:In order to reduce the clinical ADR and feasibility of ensuring quali-ty standard,the abnormal toxicity limit of Gluconate enoxacin injection should be set as 28.4 mg/kg.
3.Effect of carotid artery stenting on CBF and CVR in patients with unilateral internal carotid artery symptomatic severe stenosis
Dawei CHEN ; Jin SHI ; Jin ZHENG ; Chen SONG ; Fen YANG ; Yanwei YI ; Luna MA ; Longsong PU
Chinese Journal of Geriatric Heart Brain and Vessel Diseases 2018;20(5):470-474
Objective To study the effect of carotid artery stenting (CAS) on rCBF and rCVR.Methods Seventeen patients with unilateral internal carotid artery symptomatic severe stenosis who underwent CAS in our hospital were included in this study.Their rCBF volume and rCVR were measured by single photon emission CT scanning combined with CO2 loading test 1 week be fore and 3 months after CAS.Their data were analyzed according to the ROI in ipsilateral middle cerebral artery blood supply territory.Results Sixty eight ROIs were detected in the 17 patients with impaired rCBF in 16 ROIs (23.5%) before CAS.The mean improved rate of rCBF was significantly higher in impaired rCBF and rCVR ROI before CAS than that of rCBF in normal and impaired rCVR ROI after CAS (P=0.001).The mean improved rate of rCVR was significantly higher in normal rCBF and impaired rCVR ROI after CAS than before CAS (P=0.014).The improved rate of rCBF was significantly higher in impaired rCBF and rCVR ROI after CAS than that of normal and impaired rCVR ROI before CAS (81.3% vs 50.0%,P=0.027).The improved rate of rCVR was significantly higher in normal rCBF ROI and impaired rCVR ROI before CAS than in impaired rCBF and rCVR ROI after CAS (59.6% vs 31.3%,P=0.047).Conclusion CAS can improve the ROI rCBF and rCVR in patients with unilateral ICA symptomatic severe stenosis.Its modified model is closely related with rCBF before CAS.
4.Chicken RNA-binding protein T-cell internal antigen-1 contributes to stress granule formation in chicken cells and tissues
Yingjie SUN ; Pin ZHANG ; Hang ZHENG ; Luna DONG ; Lei TAN ; Cuiping SONG ; Xusheng QIU ; Ying LIAO ; Chunchun MENG ; Shengqing YU ; Chan DING
Journal of Veterinary Science 2018;19(1):3-12
T-cell internal antigen-1 (TIA-1) has roles in regulating alternative pre-mRNA splicing, mRNA translation, and stress granule (SG) formation in human cells. As an evolutionarily conserved response to environmental stress, SGs have been reported in various species. However, SG formation in chicken cells and the role of chicken TIA-1 (cTIA-1) in SG assembly has not been elucidated. In the present study, we cloned cTIA-1 and showed that it facilitates the assembly of canonical SGs in both human and chicken cells. Overexpression of the chicken prion-related domain (cPRD) of cTIA-1 that bore an N-terminal green fluorescent protein (GFP) tag (pntGFP-cPRD) or Flag tag (pFlag-cPRD) induced the production of typical SGs. However, C-terminal GFP-tagged cPRD induced notably large cytoplasmic granules that were devoid of endogenous G3BP1 and remained stable when exposed to cycloheximide, indicating that these were not typical SGs, and that the pntGFP tag influences cPRD localization. Finally, endogenous cTIA-1 was recruited to SGs in chicken cells and tissues under environmental stress. Taken together, our study provide evidence that cTIA-1 has a role in canonical SG formation in chicken cells and tissues. Our results also indicate that cPRD is necessary for SG aggregation.
Chickens
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Clone Cells
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Cycloheximide
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Cytoplasmic Granules
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Humans
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Protein Biosynthesis
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RNA Precursors
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RNA-Binding Proteins
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T-Lymphocytes