Objective:To establish an HPLC method for the determination of clindamycin phosphate in compound phenytoin sodi-um ge1s. Methods:The HPLC analysis was carried out on a ZORBAX SB-C18 column(250 × 46 mm,5 μm)with 0. 1 mol·L-1 KH2PO4 solution(adjusting pH to 2. 5 with H3PO4 solution)-acetonitrile(75:25)as the mobile phase at the flow rate of 0. 8 ml· min-1 . The detection wavelength was 210 nm,the column temperature was 25℃ and the injection volume was 10μl. Results:The lin-ear range of clindamycin phosphate was 3. 00-18. 00 μg(r=0. 999 5). The average recovery was 101. 11%(RSD=0. 34%,n=6). Conclusion:The method is simple,sensitive and reproducible,and can be used in the determination of clindamycin phosphate in com-pound phenytoin sodium gels.

Adult ; Corticotropin-Releasing Hormone ; blood ; urine ; Diving ; physiology ; Helium ; Humans ; Male ; Oxygen ; beta-Endorphin ; blood ; urine

Objective To investigate the effect of human lung cancer-associated fibroblasts (CAF) on the radiosensitivity of lung cancer cells when CAF is placed in direct contact co-culture with lung cancer cells.Methods Human lung CAF was obtained from fresh human lung adenocarcinoma tissue specimens by primary culture and subculture and was then identified by immunofluorescence staining.The CAF was placed in direct contact co-culture with lung cancer A549 and H1299 cells,and the effects of CAF on the radiosensitivity of A549 and H1299 cells were evaluated by colony-forming assay.Results The human lung CAF obtained by adherent culture could stably grow and proliferate,and it had specific expression of α-smooth muscle actin,vimentin,and fibroblast activation protein,but without expression of cytokeratin-18.The plating efficiency (PE,％) of A549 cells at 0 Gy irradiation was (20.0 ± 3.9) ％ when cultured alone versus (32.3 ± 5.5) ％ when co-cultured with CAF (t =3.16,P ＜ 0.05),and the PE of H1299 cells at 0 Gy irradiation was (20.6 ± 3.1) ％ when cultured alone versus (35.2 ± 2.3) ％ when co-cultured with CAF (t =6.55,P ＜0.05).The cell survival rate at 2 Gy irradiation (SF2) of A549 cells was 0.727 ±0.061 when cultured alone versus 0.782 ± 0.089 when co-cultured with CAF (t =0.88,P ＞ 0.05),and the SF2 of H1299 cells was 0.692 ±0.065 when cultured alone versus 0.782 ± 0.037 when co-cultured with CAF (t =2.08,P ＞0.05).The protection enhancement ratios of human lung CAF for A549 cells and H1299 cells were 1.29 and 1.25,respectively.Conclusions Human lung CAF reduces the radiosensitivity of lung cancer cells when placed in direct contact co-culture with them,and the radioprotective effect may be attributed to CAF promoting the proliferation of lung cancer cells.

Dihydrofolate reductase (DHFR) is a well-known key target in the treatment of tumors, bacterial infections, and parasitic infections; and it plays a critical role in the biosynthesis of cellular DNA. DHFR inhibitors interfere with one-carbon metabolism by inhibiting substrate binding to DHFR, thereby inhibiting cell proliferation. Research on DHFR inhibitors has continued since the 1940s. To date, a variety of DHFR inhibitors have come into the market, primarily used for anti-tumor, antibacterial, antiparasitic, and anti-inflammatory therapy. This review summarizes the research progress of DHFR inhibitors with antitumor or antibacterial effects in recent years based on the classification of single-target and dual-target and looks forward to the opportunities and challenges faced by the work in this field.

Adhesives ; Anti-Bacterial Agents ; Dental Cements ; Dental Materials ; Humans

BACKGROUND:A variety of embryonic stem cells induction and differentiation systems have been established so far, while the research that promotes embryonic stem cells to differentiate into hematopoietic stem cells is stil at an initial stage, and the induction efficiency needs to be improved.
OBJECTIVE:To active the Wnt/β-catenin signal pathway in mouse embryonic stem cells with exogenous win3a as an inducer, and then to observe whether the activation of this pathway wil promote the directional differentiation of embryonic stem cells into hematopoietic progenitor cells.
METHODS:The ES-E14TG2a mouse stem cells were cultured with the exogenous wnt3a (100 μg/L) for 21 days, the content ofβ-catenin was tested by cellimmunofluorescence and western blot, and expression of Wnt downstream target gene was detected by quantitative reverse transcription PCR to determine the activation of Wnt/β-catenin signal pathway. Single-layer adherent culture method was used to induce the directional differentiate of above-mentioned cells into hematopoietic stem cells, and detection of hematopoietic development associated surface marker CD34+/Sca-1+was achieved by flow cytometry;meanwhile, the expression of hematopoietic associated gene was measured by quantitative reverse transcription PCR.
RESULTS AND CONCLUSION:We found thatβ-catenin accumulated in ES-E14TG2a mouse stem cells after cultured with wnt3a (100 μg/L) for 21 days;the expressions of Wnt downstream target genes such as Pitx2, Frizzled, Sox17 and Oct4 showed the different degrees in increase, meaning the activation of Wnt/β-catenin signal pathway. Furthermore, during the time that we used single-layer adherent culture method to induce hematopoietic stem cells, the CD34+/Sca-1+cells accounted for 20.2%of total cells at day 14, and control cells only accounted for 11.9%. Again, expression quantity of hematopoietic associated gene BMP4, FLK2 and CD34 increased while Smad5 was suppressed significantly. Our data suggest that sustaining action by wnt3a wil active Wnt/β-catenin signal pathway, and also promote the directional differentiation of ES-E14TG2a mouse stem cells into hematopoietic progenitor cells.

Objective To investigate the effect of bifidobacteria on dextran sulphate sodium(DSS)- induced acute ulcerative colitis in mice.Methods Thirty BALB/C mice were randomly divided into nor- mal control group (n=10),0501 strain group (n=10) and c122 strain group (n=10).Fifty BALB/ C mice received 5% dextran sulphate sodium(DSS) for 7 days to induce ulcerative colitis.The mice were then divided to model group,negative control group(perfused with 0.9 NaCl solution ),positive control group(perfused with SASP of 20 mg/ml),DSS + 0501 strain group(perfused with 1?10~9 CFU/ml bifidobacteria 0501 strain solution and DSS + c122 strain group (perfused with 1?10~9 CFU/ml bifidobacteria c122 strain solution).All mice were sacrificed 9 days later.The colon specimens were measure by histoehemical staining with H-E.The expressions of interleukin-10 (IL-10) and its protein were detected by RT-PCR and immunohistochemistry respectively.Results The degree of colon inflam- mation in mice both in DSS+ 0501 strain and DSS+ c122 strain groups were aggravated and expressions of IL-10 mRNA and protein were reduced compared to model group.No colon inflammation was found in 0501 strain and c122 strain groups.Conclusion Some strain of bifidobaeteria may aggravate colon in- flammation in mice when mucosal harrier is destroyed.

Fermentation conditions for the production of spores of Bacillus mucilaginosus mutant 021120 were optimized through the single factor and orthogonal experiments.The results showed that the biomass and formation of spores were obviously affected by carbonate,followed by nitrogen.Addition of CaCO3 and enhancing air flux notably promoted the formation of spores.The optimal culture medium was composed of 2% starch,0.4% Yeast,0.1% K2HPO4,0.1% MgSO4?7H20 and 0.5 %CaCO3,pH7.5.6% of the inoculum prepared with two-stage extensive culture was inoculated into a 70L fermentor.The fermentation was carried out with 2.0~2.5 vvm of air flux at 32℃ for 38~42h,and the spores of 9.80?108 cfu ml-1 was obtained.Under these optimal fermentation conditions,the capsule was successfully controled and the formation of the spores was effectively improved,thus the satisfying bacteial product was obtained.

Objective To investigate the feasibility of using ultrasound‐mediated destruction of microbubbles ( US+ MB) to enhance the transplantation of endothelial progenitor cells ( EPCs) to confer chronic allograft vasculopathy (CAV) .Methods Bone marrow derived mononuclear cells were isolated and induced in vitro . The abdominal aorta transplantation was performed . Four groups were divided:control group without treatment (group A) ,injection with saline (group B) ,injection with EPCs (group C) ,group D ( US+MB+EPCs) was injected with EPCs and US was applied to MB prior to the infusion . All rats were killed during 8 weeks after transplantation to enable histological examination;SDF‐1α expression was detected by immunohistochemistry ,the expression of SDF‐1αand TNF‐αin the grafted aortas were detected with RT‐PCR . Results When 8 weeks after EPCs transplantation ,there was a significant improvement in aortic intima of Group D compared with Group B and C ,respectively ( P <0 .05) . In addition ,treatment of Group D significantly increased the expression of SDF‐1αand reduced the expression of TNF‐αin the grafted aortas . Conclusions US‐mediated MB destruction prior to EPCs transplantation into the grafted aortas can improves the effectiveness of endothelial repair and delay the progress of CAV .

Introduced in this paper are the current situation of biobank in China in the context of precision medicine.As a vital platform of precision medicine,biobank constitutes a resource support for this plan.Establishing high quality biobank has important implications for the implement of precision medicine in China.This paper focused on the problems existing in biobank development in the context of precision medicine and put forward corresponding countermeasures as well as suggestions.