Clustered regularly interspaced short palindromic repeats (CRISPR) is an acquired immune system existing in archaea and bacteria with the long-term process of evolutionary.CRISPR/Cas9 gene editing system is a new type of gene editing technology developed based on the system.CRISPR/Cas9 is a more efficient method for gene targeting than the previous methods.It has been successfully applied for gene-modified of eukaryotes since 2012,but the reports about pathogenic microorgaisms are rarely.Here,the research progress in the structure,mechanism of CRISPR/Cas9 system and its applications on pathogenic microorgaisms is reviewed.

OBJECTIVE:To compare the effects of prophylactic application of 3 different antibiotics on prognosis in patients underwent breast lesion resection. METHODS:1 066 patients with breast lasion resection from 12 hospitals of Shaanxi province were divided into trial group(360 cases),control group A(352 cases)and control group B(354 cases)according to random num-ber table. Trial group was given first generation cephalosporin cefazolin;control group A was given second generation cephalospo-rin cefuroxime;control group B was given third generation cephalosporin cefoperazone sodium and tazobactam sodium. The dosage regimens of 3 groups were as follows:relevant drug 2 g added into 0.9%Sodium chloride injection 100 ml,ivgtt,0.5 h before sur-gery,medication course≤24 h after surgery in trial group. Those indexes of 3 groups were observed,such as post-operative ADR, incision healing,infection,hospitalization duration,phamaceutical costs per capita. RESULTS:There was no statistical signifi-cance in the rate of incision healing and the rate of post-operative infection among 3 groups(P>0.05). The incidence of post-opera-tive ADR,hospitalization duration and phamaceutical costs per capita in observation group were significantly lower or shorter than in control group A and B,with statistical significance(P<0.05). CONCLUSIONS:Cefazolin is better than cefuroxime and cefo-perazone sodium and tazobactam sodium to reduce the postoperative adverse reaction,antibiotics cost per capita and hospital drug cost per capita,shorten the hospitalization duration.

OBJECTIVEThe aim of this study was to clarify whether the fusion of bone marrow mesenchymal stem cells (MSCs) with tumor cells can promote tumor angiogensis.

METHODSHuman glioma stem/progenitor cells (GSPCs) (SU3 cells) were transfected with red fluorescent protein (RFP) gene. Bone marrow mesenchymal stem cells (MSCs) were harvested from nude mice with whole-body green fluorescent protein (GFP) gene expression. Then the two kinds of cells were co-cultured in vitro. At the same time SU3-RFP was transplanted into the brain of GFP-expressing nude mice to establish xenograft tumors. The co-cultured cells, GFP/RFP double positive (yellow) cells and blood vessels obtained from the xenograft tumors were observed under fluorescent microscope and laser scanning confocal microscope.

RESULTSAfter five passages in vitro, MSCs maintained the proliferative activity and highly expressed CD105. CD105 was also expressed in the femurs of GFP-expressing nude mice, tumor cells, blood vessels of SU3 xenograft tumors, and clinical malignant gliomas. When MSCs were co-cultured with SU3-RFP, the ratio of yellow cells co-expressing RFP and GFP was significantly increased after extended time and continuous passages. According to the flow cytometry, yellow cells co-expressing RFP and GFP were 83.7% of the cultured cells. In tissue slices of the xenograft tumors, bundles of yellow vessel-like structure and cross-sectioned yellow vascular wall structures including vascular wall stroma cells were observed with RFP and GFP expression, and were identified as de novo formed vessels derived from fusion of MSCs with SU3-RFP cells.

CONCLUSIONCell fusion occurs between tumor cells and host MSCs and it promotes tumor angiogenesis.

Animals ; Bone Marrow Cells ; physiology ; Cell Communication ; Cell Fusion ; Cells, Cultured ; Glioma ; Green Fluorescent Proteins ; Humans ; Luminescent Proteins ; Mesenchymal Stromal Cells ; Mice ; Mice, Nude ; Microscopy, Fluorescence ; Neoplasms ; Neovascularization, Pathologic ; Stem Cells ; Transfection ; Transplantation, Heterologous

Ionizing radiation can directly attack biological macromolecules including DNA, protein and lipids. Radiation can also damage cells indirectly by the formation of lots of free radicals through the radiolysis of surrounding water molecules. As the result, ion-izing radiation may make serious injury in human immune system, reproductive system and nervous system. Several synthetic radiopro-tectors have been used in clinic. However, most of them have some undesirable side effects. Hence, natural radioprotectors with high efficiency and low toxicity have been the focus of radioprotection field in recent years. In the paper, the recent research progress in the protection and repair effects of polysaccharides on radiation damage was reviewed.

Objective:To study the effects and mechanisms of acetyl-11-keto-β-boswellic acid ( AKBA) in myocardial ischemic model induced by isoproterenol hydrochloride ( ISO) in rats. Methods:The SD rats were randomly divided into the sham group, model group, AKBA low dose group and AKBA high dose group. Myocardial injury model was induced by subcutaneous injection of ISO (100 mg·kg-1 ) . The change of ST segment in ECG was observed. Creatine kinase ( CK-MB) , cardiac troponin I ( cTnI) , lactate dehydro-genase( LDH) , malondialdehyde( MDA) and superoxide dismutase( SOD) in the blood were detected by ELISA. The change of histo-logical tissue was determined by HE staining, and cell apoptosis was analyzed by TUNEL assay. Results: Serum CK-MB, cTnI and LDH were decreased significantly in AKBA high dose group when compared with those in the model group. Compared with that in the model group, MDA content was lowered and the SOD activity was increased in AKBA high dose group. Furthermore, AKBA high dose group improved the pathologic changes of myocardium. TUNEL assay revealed significant reduction of cardiomyocytes apoptosis in the hearts of the ischemic rats in AKBA high dose group. Conclusion:AKBA has excellent cardioprotective effect on myocardial ischemic induced by ISO and protection of myocardial cells from injury.

Objective To investigate the effect of acarbose on waist circumference (WC) in patients with IGR. Methods A total of 46 subjects with IGT (2 hPG>7.8 mmol/L) were selected in this study. All the subjects were given diet and exercise treatment for half a month and then treated with acarbose for 3 months in combination with life style modification. Self-paired method was adopted to compare islet βcell function and WC before and after the treatment. Results After acarbose treatment for 3 months ,islet βcell function were markedly improved. Insulin secretion of Fins and 2 hIns decreased ,early insulin secretion index (ΔI30/ΔG30 ) significantly increased ,and BMI and WC were reduced significantly (P<0.05) . Multiple regression analysis showed that there was correlation between WC and TG ,insulin resistance index (HOMA-IR) and islet β-cell function index (HOMA-β) (P< 0.05). Conclusion Acarbose in combination with life style modification can improve islet β-cell function in patients with IGR and reduce WC and abdominal fat accumulation as well.

Objective The aim of this study was to clarify whether the fusion of bone marrow mesenchymal stem cells ( MSCs) with tumor cells can promote tumor angiogensis.Methods Human glioma stem/progenitor cells (GSPCs) (SU3 cells) were transfected with red fluorescent protein (RFP) gene.Bone marrow mesenchymal stem cells ( MSCs) were harvested from nude mice with whole-body green fluorescent protein (GFP) gene expression.Then the two kinds of cells were co-cultured in vitro.At the same time SU3-RFP was transplanted into the brain of GFP-expressing nude mice to establish xenograft tumors.The co-cultured cells, GFP/RFP double positive ( yellow ) cells and blood vessels obtained from the xenograft tumors were observed under fluorescent microscope and laser scanning confocal microscope.Results After five passages in vitro, MSCs maintained the proliferative activity and highly expressed CD105.CD105 was also expressed in the femurs of GFP-expressing nude mice, tumor cells, blood vessels of SU3 xenograft tumors, and clinical malignant gliomas.When MSCs were co -cultured with SU3-RFP, the ratio of yellow cells co-expressing RFP and GFP was significantly increased after extended time and continuous passages. According to the flow cytometry, yellow cells co-expressing RFP and GFP were 83.7%of the cultured cells. In tissue slices of the xenograft tumors, bundles of yellow vessel-like structure and cross-sectioned yellow vascular wall structures including vascular wall stroma cells were observed with RFP and GFP expression, and were identified as de novo formed vessels derived from fusion of MSCs with SU3-RFP cells.Conclu sion Cell fusion occurs between tumor cells and host MSCs and it promotes tumor angiogenesis.

Objective The aim of this study was to clarify whether the fusion of bone marrow mesenchymal stem cells ( MSCs) with tumor cells can promote tumor angiogensis.Methods Human glioma stem/progenitor cells (GSPCs) (SU3 cells) were transfected with red fluorescent protein (RFP) gene.Bone marrow mesenchymal stem cells ( MSCs) were harvested from nude mice with whole-body green fluorescent protein (GFP) gene expression.Then the two kinds of cells were co-cultured in vitro.At the same time SU3-RFP was transplanted into the brain of GFP-expressing nude mice to establish xenograft tumors.The co-cultured cells, GFP/RFP double positive ( yellow ) cells and blood vessels obtained from the xenograft tumors were observed under fluorescent microscope and laser scanning confocal microscope.Results After five passages in vitro, MSCs maintained the proliferative activity and highly expressed CD105.CD105 was also expressed in the femurs of GFP-expressing nude mice, tumor cells, blood vessels of SU3 xenograft tumors, and clinical malignant gliomas.When MSCs were co -cultured with SU3-RFP, the ratio of yellow cells co-expressing RFP and GFP was significantly increased after extended time and continuous passages. According to the flow cytometry, yellow cells co-expressing RFP and GFP were 83.7%of the cultured cells. In tissue slices of the xenograft tumors, bundles of yellow vessel-like structure and cross-sectioned yellow vascular wall structures including vascular wall stroma cells were observed with RFP and GFP expression, and were identified as de novo formed vessels derived from fusion of MSCs with SU3-RFP cells.Conclu sion Cell fusion occurs between tumor cells and host MSCs and it promotes tumor angiogenesis.

Objective To investigate the effect of two different blood purification methods on serum parathyroid hormone(PTH) in chronic hemodialysis patients. Methods 101 patients were randomly divided into two groups:hemodialysis + hemoperfusion group( HD + HP group) and hemodiafiltration group( HDF group). Patients in HD + HP group were treated with resin absorptive devices combined hemodialysis, patients in HDF group treated with hemodiafiltration. Routine determination of serum phosphorus and radioimmunoassay of PTH level were carried out before and after treatment. Results HDF group and HP + HD group were effective for the removal of serum phosphorus,and the clearance rate was no significant difference(P ＞0. 05). HDF group and HP + HD group could all effectively eliminate the middle molecular substance PTH, but the clearance rate of HDF group was better than that of HP + HD group,the difference was statistically significant (P ＜ 0. 05 ). Conclusion HDF could safely and effectively clear PTH and had better effect than HD + HP.

Objective To investigate the safety and clinical outcome of total body irradiation (TBI) and the real-time in vivo dosimetry with semiconductor dosimeter in hematogenous stem cell transplantation (HSCT). Methods Fifty-seven patients requiring HSCT were treated with TBI. The TBI was given with the semi-sitting or standing position or lateralcumbent posture, using 6 MV X-ray beams and opposed parallel fields technique (two or four fields, AP/PA fields) in a single fraction or multiple fractions. The real-time in vivo dosimetry was performed with six diodes positioned on the surface of patients to adjust the dose homo-geneity of the midplane using the different thickness lead sheets. Results Mild to moderate nausea, vomi-ting and swollen parotid occurred in 41 patients after TBI, which were relieved after allopathy therapy. No radiation-induced interstitial pneumonia was observed. All patients fulfilled the HSCT. The homogeneity of relative dose (normalize to umbilicus dose) in the different positions accorded with the requirement of the prescription dose. Conclusions The opposed parallel radiation, with the semi-sitting or standing positions or lateralcumbent posture, combined with the real-time in vivo dosimetry with semiconductor dosimeter is an effective and safe technique for TBI.