1.Advances in transcription activator-like effectors--a review.
Chinese Journal of Biotechnology 2015;31(7):1024-1038
As a protein originally found in plant pathogenic bacteria, transcription activator-like effectors (TALEs) can be fused with the cleaving domain of restriction endonuclease (For example Fok I) to form artificial nucleases named TALENs. These proteins are dependent on variable numbers of tandem Repeats of TALEs to recognize and bind DNA sequences. Each of these repeats consists of a set of approximately 34 amino acids, composed of about 32 conserved amino acids and 2 highly variable amino acids called repeat variant di-residues (RVDs). RVDs distinguish one TALE from another and can make TALEs have a simple cipher for the one-to-one recognition for proteins and DNA bases. Based on this, in theory, artificially constructed TALENs could recognize and break DNA sites specifically and arbitrarily to perform gene knockout, insertion or modification. We reviewed the development of this technology in multi-level and multi species, and its advantages and disadvantages compared with ZFNs and CRISPR/Cas technology. We also address its special advantages in industrial microbe breeding, vector construction, targeting precision, high efficiency of editing and biological safety.
Amino Acid Motifs
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Biotechnology
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DNA
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chemistry
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Endonucleases
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chemistry
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Tandem Repeat Sequences
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Trans-Activators
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chemistry
3.Digital imaging fiber optic transillumination (DIFOTI) method for determining the depth of cavity
Jiangli YU ; Rentao TANG ; Lin FENG ; Yanmei DONG
Journal of Peking University(Health Sciences) 2017;49(1):81-85
Objective:To analyze the accuracy of the digital imaging fiber optic transillumination (DIFOTI) on diagnosis of caries lesions depth using DIAGNOcam system.Methods:This experiment adopted self-matching design.Seventy-four extracted teeth (molar:sixty-six,premolar:eight) with one caries lesions in proximity which were not damaged in surface marginal ridge were selected.Dental calculus and dental stains were removed from the extracted teeth for standby application.A sign was marked in the middle of the occlusal surface edge at the side of decay.Then the teeth were fixed in the standard model of dentition and cavities were adjacent with the sound tooth surface.Sticky wax was applied to seal the level of 2 mm beyond cemento-enamel junction (CEJ) in the direction of occlusion and interproximal space to imitate gingival margin and gingival papilla.The standard models of dentition was seated in imitation head mold.The lesions depth degree was looked into and checked with DIAGNOcam system.Besides,the pictures on the occlusal surfaces were recorded and saved.The sign above could be seen on the picture.The measuring tool in DIAGNOcam system was used to measure the depth of the caries from the sign (as starting point) to the deepest point of caries in the pictures and its length was recorded for a.The line a was lengthened to the contralateral edge of occlusal surface in the photo and the length was recorded for b.A line from the marked point on the occlusal surface edge of the extracted teeth was draw parallel to the line b on the corresponding photo and its length was recorded for c.The depth of the cavities on the projected images was recorded for d,and calculated d/a =c/b (digital optical fiber measured decay depth/caries damage depth of the image =actual tooth width/tooth width of the image),and d =c/b × a inferred.At last,the teeth were taken out from the standard model dentition.The decay of the tooth was removed completely.The actual depth of the cavity was recorded for D.The difference between d and D was recorded for Δd.The software of SPSS 20.0 was used to test the consistency of the results,and the MedCalc 14.8.1.0 software was used for Bland-Altman analysis.Results:The intraclass correlation coefficient (ICC) between d and D was 0.951 (ICC > 75 %),P =0.263.There was a function relationship y =0.23 ± 0.9 1x between d (x) and D (y).Bland-Altman analysis method showed that the mean of Δd (Δd) was 0.05 mm,the standard deviation of Δd (ΔdsD) =0.308,and the 95% confidence interval was (-0.55 to 0.65).The amplitude of difference was clinically acceptable.So the consistency of the two measurement modes was high.Conclusion:There was no significant difference between the depth of caries lesions checked with DIAGNOcam system and the depth of the actual cavity,and the consistency was very good.The vitro study suggests that the DIAGNOcam system may be used to assess the depth of caries cavity as a useful tool in diagnosis and treatment.
4.Low-dose ATRA supplementation abolishes PRM formation in rat liver and ameliorates ethanol-induced liver injury.
Zhihong, PAN ; Zili, DAN ; Yu, FU ; Wangxian, TANG ; Jusheng, LIN
Journal of Huazhong University of Science and Technology (Medical Sciences) 2006;26(5):508-12
The effects of all-trans-retinoic acid (ATRA) in low doses supplementation on concentrations of polar retinoid metabolites (PRM) and retinoids in the ethanol-fed rat liver, and on hepatocyte injury were investigated. The rat model of alcoholic liver disease (ALD) was induced by intragastric infusion of ethanol, and then the rats were administrated with ATRA in two different doses (150 microg/kg body weight and 1.5 mg/kg body weight) for 4 weeks. Concentrations of retinoids in rat liver and plasma were determined by using HPLC. Liver tissues pathologic changes were observed under the light microscopy and electron microscopy. The serum transaminases concentrations were measured. The results showed that the HPLC analysis of retinoids revealed that retinoids (vitamin A, RA, retinyl palmitate) concentrations in ethanol-fed rat liver and RA concentration in ethanol-fed rat plasma were markedly diminished (P<0.01) after ethanol feeding for 12 weeks. Furthermore, obvious peaks of PRM were formed in livers of ethanol-fed rats. ATRA 150 microg/kg supplementation in ethanol-fed rats for 4 weeks raised RA concentration in both liver and plasma, and also raised vitamin A concentration in liver to control levels, partially restored retinyl palmitate concentration (P<0.05) in liver. ATRA 1.5 mg/kg supplementation raised not only RA concentrations in liver and plasma but also retinyl palmitate concentrations in liver. However, the vitamin A concentration in liver of ATRA-supplemented rats (1.5 mg/kg) was higher than that of controls (P<0.05). The histologic observation of liver tissues indicated that ATRA treatment notably alleviated hepatocellular swelling, steatosis, the swelling of mitochondria and proliferation of smooth endoplasmic reticulum (SER). ATRA treatment greatly decreased levels of serum transaminases as compared with the only ethanol-fed group (P<0.05). It was concluded that low-dose ATRA treatment could restore retinoids concentrations and abolish the PRM formation in liver of ALD rats, and then ameliorate the injury of liver cells.
5.Biodistribution and Postmortem Redistribution of Emamectin Benzoate in Intoxicated Mice.
Wei-wei TANG ; Yu-cai LIN ; Yan-xu LU
Journal of Forensic Medicine 2016;32(1):26-30
OBJECTIVE:
To investigate the lethal blood level, the target organs and tissues, the toxicant storage depots and the postmortem redistribution in mice died of emamectin benzoate poisoning.
METHODS:
The mice model of emamectin benzoate poisoning was established via intragastric injection. The main poisoning symptoms and the clinical death times of mice were observed and recorded dynamically in the acute poisoning group as well as the sub-acute poisoning death group. The pathological and histomorphological changes of organs and tissues were observed after poisoning death. The biodistribution and postmortem redistribution of emamectin benzoate in the organs and tissues of mice were assayed by the enzyme-linked immunosorbent assay (ELISA) at 0h, 24h, 48h and 72h after death. The lethal blood concentrations and the concentrations of emamectin benzoate were detected by high performance liquid chromatography (HPLC) at different time points after death.
RESULTS:
The symptoms of nervous and respiratory system were observed within 15-30 min after intragastric injection. The average time of death was (45.8 ± 7.9) min in the acute poisoning group and (8.0 ± 1.4) d in the sub-acute poisoning group, respectively. The range of acute lethal blood level was 447.164 0-524.463 5 mg/L. The pathological changes of the organs and tissues were observed via light microscope and immunofluorescence microscope. The changes of emamectin benzoate content in the blood, heart, liver, spleen, lung, kidney and brain of poisoning mice showed regularity within 72 h after death (P < 0.05).
CONCLUSION
The target organs of emamectin benzoate poisoning include heart, liver, kidney, lung, brain and contact position (stomach). The toxicant storage depots are kidney and liver. There is emamectin benzoate postmortem redistribution in mice.
Animals
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Autopsy
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Chromatography, High Pressure Liquid
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Dose-Response Relationship, Drug
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Enzyme-Linked Immunosorbent Assay
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Ivermectin/toxicity*
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Lethal Dose 50
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Mice
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Postmortem Changes
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Tissue Distribution
6.Primary testicular non-Hodgkin's lymphoma
Zhiyong CHEN ; Lin QI ; Jiansong WANG ; Yu LIU ; Zhengyan TANG
Chinese Journal of Urology 2009;30(5):351-353
Objective To summarize the clinical presentation, pathology features, and treat-ment principle for primary testicular non-Hodgkin's lymphoma. Methods Twelve patients were di-agnosed with primary testicular lymphoma. The mean age was 62 years (36-78). Of the patients, unilateral primary testicular tumors were found in 11 cases and bilateral tumors were found in 1 case. All cases had swollen testes, 3 cases had mild pain and 1 had low-grade fever. Ultrasonic examination detected solid mass in all 12 cases. CT scan revealed retroperitoneal enlarged lymph nodes in 3 cases. Nine patients were diagnosed with disease of stage Ⅰ E, 2 of stage Ⅱ E, and 1 of stage Ⅲ E. All of the patients underwent radical orchiectomies. Postoperative treatment included: CHOP chemotherapy for 10 cases, radiotherapy after chemotherapy for 5 cases, and surgery alone for 2 cases. Results Post-operative pathology results were non-Hodgkin's lymphoma in all cases. One patient lost in follow up, one died within 2 years because of other disease. The 1, 3 and 5 year actual survival rates were 82% (9/11) ,40%(4/10),20% (2/10), respectively. The relapsed organs included contralateral testis(3/ 11), central nervous system(3/11), liver(1/11)and retroperitoneal lymph node(1/11). Conclusions The prognosis of the primary testicular non-Hodgkin's lymphoma is very poor. Chemotherapy must be used after surgery for any stage. Stage Ⅰ E and Ⅱ E patient should be treated by surgery combined with radiotherapy and chemotherapy. Contralateral testis should be irradiated prophylactically. Pa-tients beyond stage Ⅱ E should accept chemotherapy after surgery and radiotherapy according to the patient's status.
7.Effect of Tanyu-Tongzhi recipe on Rho/Rho kinase signal transduction pathway of myocardial ischemia-reperfusion injury in rats
Danli TANG ; Lin TONG ; Haifeng CUI ; Yu SUI ; Huamin ZHANG
International Journal of Traditional Chinese Medicine 2013;35(12):1082-1085
Objective To investigate the influence of Tanyu-Tongzhi (TYTZ)recipe on Rho/Rho kinase signal transduction pathway of myocardial ischemia-reperfusion injury in high fat-fed rats.Methods 60 SD rats were divided into 5 groups randomly,a sham-operated group,a model group,a western medicine control group,a high-dose group and a low-dose group of TYTZ recipe.The model of ischemia reperfusion of the myocardium was reproduced by ligation of left descending artery for 30 min followed by releasing the ligation for 2 hours in rats.The downstream substrates of ROCK myosin light chain (MLC) phosphorylation expression of myocardial tissues in rats were detected by Western blotting method.The levels of RhoA,ROCK Ⅱ mRNA were determined with RT-PCR.Results Compared with the model group,the expression of p-MLC and RhoA,ROCK Ⅱ mRNA were lower in low-dose group of TYTZ,there were significant differences between the two groups(P=0.004、0.003、0.018、0.004,P<0.01).Conclusion The TYTZ Recipe can protect myocardium from MI/RI.The mechanism of action was related to its inhibiting the protein expression of RhoA,ROCK Ⅱ and p-MLC,restraining the activation of Rho/Rho kinase signal transduction pathway.
8.A survey on chronic heart failure management in community physicians in Chengdu
Xiuqiong YU ; Hui JIANG ; Mei DAI ; Jiong TANG ; Lin CAI
Chinese Journal of General Practitioners 2013;12(8):634-635
A questionnaire survey on chronic heart failure management was conducted in 110 physicians from Xindu,Supo,Jiajiang and Xinhua community hospital in Chengdu from January 2007 to June 2010.Results showed that 77.3% (85/110) of community physicians lacked knowledge about prevention,diagnosis and treatment of chronic heart failure,and the diagnostic accuracy rate was only 51.3% (40/78) in these community hospitals.There was lack of awareness of the guideline of chronic heart failure:the rate of β blockers use was 15.0% (6/40) and only 5.0% (2/40) used the target dose; the rate of angiotensin converting enzyme inhibitor use was 17.5% (7/40) and only 7.50% (3/40) used the target dose.In addition,90% (99/110) of community doctors lacked the education and management for patients with heart failure.The survey suggests that the current situation of chronic heart failure management in community physicians in Chengdu is unsatisfactory.It is necessary to strengthen the training of community physicians.
9.Isolation,Characterization and Identification of SD Rats′ Oligodendrocyte Precursor Lineage Cells in vitro
jun, TANG ; lin, ZHONG ; yu-jia, YAO ; juan, CHEN
Journal of Applied Clinical Pediatrics 2006;0(23):-
Objective To obtain highly purified oligodendrocyte precursor lineage cells in vitro and make identification.Methods The oligodendrocyte precursors were separated from astrocyte by orbital shaker and further purified by differential adhesion,and finally cultured in chemically defined serum-free medium,with appended neurotrophin 2(N2),platelet-derived growth factor(PDGF),basic fibroblast growth factor(bFGF).Immunofluorescence assay was applied to identify the separated cells with A2B5,O4,O1 and glial fibrillary acidic protein(GFAP) antibodies.Results Over 95% of cultured oligodendrocyte precursor cells were obtained.The oligodendrocyte progenitors were A2B5 and O4 positive,immature oligodendrocytes were O4 and O1 positive while GFAP were negative.Conclusions Separation and purification by shaking and differential adhesion and chemically defined medium are suitable and effective to obtain highly purified oligodendrocyte precursor cells.Cell output will increase notabily and rest in immature phase by appending both N2,PDGF and bFGF.
10.Transforming growth factor-? conjugated with cytotoxin saporin inhibits specifically proliferating vascular smooth muscle cells
Jun YANG ; Shuguang LIN ; Xiyong YU ; Qidong TANG ;
Chinese Pharmacological Bulletin 1987;0(02):-
AIM To testify the special cytotoxicity of TGF? SAP on proliferating vascular smooth muscle cells and endothelial cells. METHODS Conjugation of saporin to TGF? was accomplished after derivatization of saporin and TGF? with N succinimidyl 3 (2 pyridyldithio) proprionate. Cytotoxicity assays were measured by cell count. The studies of influence of TGF? SAP on values of thymidine and leucine incorporation into SMCs and ECs were measured by 3H thymidine uptake and 3H leucine uptake, respectively. RESULTS Cytotoxicity assays testified TGF? SAP conjugate could inhibit remarkably proliferation of SMCs in culture. The values of thymidine of TGF? SAP group (1?10 -9 mol?L -1 and 1?10 -7 mol?L -1 ) in comparison significantly decreased to 60 9% and 56 0% of the control group respectively, suggesting that cellular DNA synthesis obviously decreased as TGF? SAP was added. But saporin did not affect cellular DNA synthesis at higher level. The rate of 3H leucine incorporation of TGF? SAP group significantly decreased to 47 3% of the control group, suggesting that SMCs protein synthesis obviously decreased as TGF? SAP was added. But TGF? SAP at the same level did not affect DNA synthesis and protein synthesis of ECs compared with the control group. CONCLUSION TGF? SAP possesses the more effective cytotoxicity than saporin and the more specific citotoxicity on proliferating vascular smooth muscle cells than on proliferating endothelial cells.