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 ; Biotechnology ; DNA ; chemistry ; Endonucleases ; chemistry ; Tandem Repeat Sequences ; Trans-Activators ; chemistry

The article retrospectively analyzes the clinical characteristics and prevention measures of cytomegalovirus (CMV) infections after renal transplantation in 395 patients from Beijing Friendship Hospital Affiliated to Capital Medical University. All patients received preventive treatment of CMV infections and pneumocystis carinii infections in three months after renal transplantation. CMV infections occurred in 24 of 395 patients. The patients with viremia were treated with Ganciclovir or foscarnet sodium. The patients with severe infections (eg. severe pulmonary infections) should be treated with decrease dosage of immunosuppressive drugs, even stop administration. Then the immunosuppressive drugs were adopted again if the infections were controlled. Twenty-four patients obtained the satisfied efficacy. The results suggested that evaluation of the risk for CMV infections before transplantation, preventive treatment in early time after transplantation, measurement of clinical epidemiology, early diagnosis, and individual medication scheme of immunosuppressive drugs for patients should be effective to prevent and against CMV infections. And they also played an important role in preventing acute allograft rejection after renal transplantation and protecting the function of the graft.

Objective To analyze the clinical and immunological manifestations of antiphospholipid syndrome(APS)in a cohort of 100 patients.Methods The clinical and serologic features of APS(Sapporo preliminary criteria)in 100 patients were analyzed retrospectively.Results The cohort consisted of 79 female patients and 21 male patients witb a mean age of 36?13 years at diagnosis.Primary APS was presented in 37% of patients;APS was secondary to systemic lupus erythematosus(SLE)in 46%,lupus-like syndrome in 14%. Eighty percent of the patients had thrombosis,43(54%)patients had venous thrombosis,18(22%)had arterial thrombosis,15(19%)had both arterial and venous thrombosis.4(5%)had thrombosis of microcirculation. Forty-two(52%)patients presented thrombosis at a single site,26(32%)at two sites,12(15%)at three or more sites.Forty-five(56%)patients experienced one thrombotic episode,20(25%)patients had only one re- currence,and 15(19%)had more thrombosis.The most common manifestations of thrombosis were deep vein thrombosis(36%),pulmonary embolism(30%)and stroke(26%),with heart,kidney,gastrointestinal tract and other organs involvements.Thirty-four(51%)female patients had spontaneous fetal losses including intrauter- ine fetus death and recurrent spontaneous abortion.Seventy-one(71%)patients developed thromboeytopenia. The presence of antieardiolipin antibody(ACL)was detected in 84 patients(84%).Among 90 patients with APS,alone ACL was detected in 38 patients(42%),both ACL and lupus anticoagulant(LA)were detected in 36(40%),LA alone in 16(18%).Patients with APS associated with SLE or lupus-like syndrome had higher frequency of arthritis,leukopenia,antinuclear antibodies(ANA)and low complement levels.Female patients had a higher frequency of leukopenia,ANA and ACL.Male patients had a higher prevalence of deep venous thrombosis in the lower limbs and LA.Conclusion APS is an autoimmune disorder characterized by recurrent arterial and venous thrombosis,fetal loss,or thrombocytopenia with the presence of ACL and/or LA.In APS secondary to with SLE,the patient's sex can modify the disease expression and define specific subsets of APS.

Objective To study the clinical significance of MR imagings features in the diagnosis on central neurocytoma ( CNC ) . Methods From January 2010 to December 2012,9 patients with CNC were analyzed and examined by MRI before surgery,then received postoperative pathology examination. Results CNC were in the left lateral ventricle of 9 patients, closely linked with the Monro hole, of which 4 cases were in the first 2/3 of central ventricle of the left lateral ventricle,3 cases in the septum pellucidum and growth to bilateral ventricles,2 cases of infiltrating in the septum pellucidum and base side adhesion. For CNC,MRI signal was not uniform,solid part T1WI showed equal or slightly low signal,multiple cysts and signal cord like structure with the ventricular wall and septum pellucidum adhesion. By contrast-enhanced CT scan,there were the solid part heterogeneous obvious enhancement in 4 cases,moderate and slight uneven enhancement in 3 cases and 2 cases respectively. Uniform size,round or oval cells were showed by HE staining,and the synaptophysin was positive in 6 ca-ses by immunohistochemical staining,positive expression of glial fibrillary acidic protein in 3 cases. After operation,3 patients were lost to fol-low up,for 6 cases were followed up,survival of 2 cases in 3 years,4 cases in 2 years. Conclusion The results suggest that MRI display is located near the lateral ventricle central Monro hole before and lesions suggestive of CNC in young patients. For most CNC,synaptophysin has positive expression by immunohistochemical staining.

ObjectiveTo study the sirolimus (SRL)-associated interstitial pneumonitis,which is a severe side effect of sirolimus therapy. Methods In 7 renal grafts treated with SRL, interstitial pneumonitis (8 times) was diagnosed. One patient suffered a relapse after sirolimus treatment was given again. Two patients received de novo sirolimus treatment, and rest 5 patients were switched from a calcineurin inhibitor-containing regimen to a SRL-based protocol for various indications: chronic allograft nephropathy (n = 4) and cancer (n = 1 ). The patients presented with fever, dyspnea on exertion and the chest X-ray or computed topographic (CT) scan on admission showed bilateral mostly peripheral interstitial infiltrates. ResultsSRL was discontinued in 4 patients and the dose was reduced in the remaining 3 patients. Symptoms were improved within 3-14 days in all patients, the radiographic findings improved within 2-4 weeks, and the lesions were absorbed completely in 2-6 months.ConclusionThe frequency of interstitial pneumonitis appears to be increased in renal transplant patients receiving SRL. Discontinuation or reduced dose of SRL appears to be the safest treatment option for the patients with interstitial pneumonitis.

Objective To establish the HPLC fingerprint of Eupatorium chinense.Methods The ana-lysis was performed on a Kromasil C18 column(250 mm?4.6 mm,5 ?m) with acetonitrile-water as mobile phase in a gradient mode.The flow rate was 1.0 mL/min.The column temperature was 25 ℃ and the detection wavelength was 230 nm.Results The fingerprint of E.chinense with common 13 peaks was established.The relative retention time and the ranges of relative area of the common peaks were determined.Conclusion The established fingerprint could be used for the quality control of E.chinense.

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.

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.

Histocytochemistry ; methods ; Humans ; Pathology, Clinical ; methods ; Specimen Handling ; methods ; Staining and Labeling ; methods

Immunohistochemical technique was an essential tool of conventional diagnosis,therefore,the application of immunohisto- chemistry in reformation of pathology laboratory teaching would boost pathological experimental teaching standards to a higher level.