Comparison of methods for extraction of short RNA-DNA hybrids / 军事医学

Objective To compare the effects of three different methods for extracting short RNA-DNA hybrids, including the TRI reagent method , the phenol saturated with water method and the phenol saturated with Tris buffer method in order to facilitate studies on the biological function of RNA-DNA hybrids .Methods Short RNA fragments modifiedwith FAM at the 5′end and those modified with Cy 5 at the 5′end were synthesized .RNA and DNA fragments were annealed to form RNA-DNA hybrids.They were extracted with the above-mentioned 3 methods respectively .The extracted products were analyzed with electrophoresis .Results and Conclusion Short RNA-DNA hybrids can be extracted by the phenol saturated with water method and by the phenol saturated with Tris buffer method .The results can help study the function of short RNA-DNA hybrids .

Role of Abro1 in LPS-induced acute lung injury / 军事医学

Objective To investigate the effect of Abro1 on acute respiratory distress syndrome(ARDS)/acute lung injury(ALI)in mice.Methods Abro1 knock-out(KO)mice and wild type(WT)mice were both randomly divided into two groups for intratracheal instillation of lipopolysaccharide(LPS)or normal saline.At 6 or 24 hours after treatment, the pathological changes in lung tissue were observed by HE staining.At 6 hours after treatment,inflammatory immune cells and cytokines production(IL-6)in the bronchoalveolar lavage fluid were examined.Myeloperoxidase(MPO)and the mRNA level of IL-6 in the lung tissue were compared.Results At 24 hours after treatment, compared with WT mice treated with LPS,Abro1 KO mice showed a significantly lower lung injury score.At 6 hours after treatment,Abro1 depletion resulted in reduced levels of inflammatory immune cell infiltration and cytokines production(IL-6)in the bronchoalveolar lavage fluid(P<0.05).In addition,the MPO content and the mRNA level of IL-6 in the lung tissue were much lower than those in WT mice treated with LPS for 6 hours(P<0.05).Conclusion Abro1 deficiency can attenuate LPS-induced ARDS/ALI.

Protective effect of HS-6101 on rhesus monkeys with severe hematopoietic acute radiation sickness / 中国实验血液学杂志

This study was purposed to investigate the protective effects of lipoprotein HS-6101(6101) on rhesus monkey total body irradiated with 7.0 Gy ⁶⁰Coγ-ray. A total of 30 health adult rhesus monkeys were randomly divided into symptomatic therapy (ST), WR2721 and HS-6101 30, 90 and 270 mg/kg groups (n = 6), the rhesus monkeys of each groups were injected with physiological saline 0.3 ml/kg, WR-2721 30 mg/kg, or HS-6101 30, 90 and 270 µg/kg, respectively. All agents were once intramuscularly injected at 1 hr prior irradiation. General observation, peripheral blood cell counts, colony forming unite assay of bone marrow hemopoietic progenitor cells, and histopathological examination were performed. The results showed that animals in symptomatic therapy group begin to die on the 13(th) day and 4 animals died within 24 days, the average survival time was 18.2 ± 4.3 days; 2 animals in WR-2717 groups died on day 15.8 and day 18.5 post irradiation respectively. 1 animal in HS-6101 270 mg/kg group died on day 35.8, all other animals survived. Nadirs of peripheral blood white blood cells, neutrophils and platelets of animals in HS-6101 treatment groups were significantly higher than those in other 2 groups including ST and WR-2721 groups, and the hemopoietic recovery were also significantly speeding up(P < 0.05 and 0.01). In vitro results showed that HS-6101 obviously promoted 7.0 Gy ⁶⁰Coγ irradiated monkey's bone marrow mononuclear cells to form various hematopoietic progenitor cell colonies (P < 0.05 and 0.01) . Compared with symptomatic therapy and WR-2717 groups, bone marrow histopathological changes in HS-6101 treatment groups showed more active hemopoietic cell proliferation and higher density structure. It is concluded that HS-6101 90 µg/kg treatment can promote the bone marrow recovery of 7.0 Gy ⁶⁰Coγ irradiated monkey, alleviate their animal symptom, simplify the treatment measures and improve the animal survival rate. The HS-6101 shows remarkable radioprotective effects as compared with the currently internationally acknowledged radioprotectant of WR-2721.

Lentivirus packaging, concentration and infection of CD34~+ cells from umbilical blood / 军事医学科学院院刊

Objective:To methodologically establish the lentivirus granule packaging, concentration and infection against CD34~+ cells from umbilical blood. Methods:The lentivirus system of the 3~(rd) generation was used to produce the virus. Ultrafiltration and ultracentrifugation were employed to concentrate virus. Several treatments were used to improve virus infection including in vitro amplification culture, facilitation of rest cells into cell cycle, promotion of cell adhesion and immobilization during infection, and repeat infection methods. Results:CD34~+ cells were not obviously changed by checking the expression level of CD34 marker on the cell surface after 48 h culture. After two-step concentration, virus titer was increased up to 5.06×10~7/ml, and the infection rate against CD34~+ cells from umbilical blood was increased up to 37.7%.Conclusion:Lentivirus supernatant with over 10~7/ml titer can be obtained using the above methods. Efficient infection against CD34~+ cells from umbilical blood can be achieved.