Objective To detect the mutant prevention concentration (MPC) of macrolide resistant Streptococcus pneumoniae, to amplify the resistance gene of Streptococcus pneumoniae mutants selected in the mutant selection window (MSW), and to investigate the mechanism in the resistance of Streptococcus pneumoniae to macrolides. Methods The Streptococcus pneumoniae strain ATCC49619 was enriched in broth, and the bacterial concentrations were adjusted to 1010 colony forming units per milliliter. The minimal inhibitory concentration (MIC), MIC for 99 % of input cells (MIC99), provisional MPC (MPCpr), and MPC of roxithromycin and azithromycin for Streptococcus pneumoniae were determined by agar plate dilution method. The ermB and mefA of Streptococcus pneumoniae mutants selected in the MSW were obtained by PCR method and sequencing. Results The MPCs of roxithromycin and azithromycin for ATCC49619 were 0.80 ?g/ml and 0.51 ?g/ml, and the MPC/MIC99 were 5.0 and 3.9. The ermB gene was detected in Streptococcus pneumoniae mutants selected in the MSW. Conclusion Adjustment of the drug dose may limit the enrichment of macrolide-resistant Streptococcus pneumoniae mutant. The mechanism in the resistance of Streptococcus pneumonia to macrolides may be associated with ermB genes carried.

Fed-batch culture is the predominant mode of the current animal cell culture process for many recombinant protein production. Fed-batch culture operation is mainly based on the nutrient continuous consumption and demand of cells to design continuous or semi-continuous concentration feed medium to maintain or support high-density cell growth and improve volumetric productivity of target protein in the reactor. The main methods to improve production efficiency of fed-batch cells culture include the optimization of medium design, selection and optimization of feed strategy and regulation of cell metabolism.

Objective To study the effects of vitamin A deficiency(VAD)and its supplementation on the skeletal growth in rats.Methods Eighteen female Wistar rats were randomly divided into VAD(Vit A 400 IU/kg diet,n=3),supplement(n=9)and control groups(normal diet Vit A 6 500 IU/kg,n=6).The supplement groups were randomly divided into 3 sub-groups,and their diet was changed to Vit A 6 500 IU/kg diet from 14 d after pregnancy,0 d and 4 weeks after birth respectively until they were 7 weeks age old.When they were 0 day,4 and 7 weeks old,their body weight,the length of the tibia,serum Vit A level were measured,and the histology of growth plate was also observed.Results At every measuring times,the serum Vit A level was significantly lower,and the tibial length was shorter in VAD group than in the control(P

AIM:To evaluate the effects of pilocarpine, brinzolamide and the preservatives of them on corneal epithelial cells and the histopathology of rabbit conjunctiva. METHODS: Fifteen New Zealand white rabbits weighing 1.5 kg to 2.5 kg were randomly divided into three groups. One group with three rabbits served as untreated controls. Pilocarpine 1% and brinzolamide 1% each were administered to the right eyes in one treated group, and the preservatives (chlorobutanol 0.01% in pilocarpine, benzalkonium chloride 0.01% in brinzolamide) to the left eyes. Corneal epithelial damage was evaluated by scanning electron microscopy, and conjunctival specimens were examined under light microscopy. RESULTS: Compared with normal controls, brinzolamide and BAC caused corneal epithelium damage and increased number of inflammatory cells in the conjunctiva, while pilocarpine and the preservative chlorobutanol mainly influenced the corneal epithelium. Brinzolamide produced significantly more damage than pilocarpine (P

OBJECTIVE: To investigate the possible role of Caspase 3 and Bcl - 2 in arsenic trioxide(As2 O3) - induced apoptosis of Namalwa cell line .METHODS: Cell apoptosis was assessed through agarose gel elecrophroresis and the double staining of Annexin V and propidium iodide(PI), of which fluorescent intensities were measured on flow cytometer.Namalwa cells were treated with As2 O3 and DEVD - CHO, a selective inhibitor of Caspase 3,and the changes of expression of Caspase 3 and Bcl - 2 were observed .RESULTS: As2 O3 up - regulated Caspase 3 protein and down - regulated Bcl - 2 protein. DEVD-CHO inhibited the apoptosis induced by As2O3. but it had no effect on down - regulation of Bcl - 2 protein induced by As2O3.CONCLUSION:The activation of Caspase 3 may play a role in mediating apoptosis induced by As2O3 in Namalwa cells.

Background Lowing intraocular pressure (IOP) is the only effective treating method in glaucoma.Making sure the change of optic disc parameters and retinal nerve fiber layer thickness(RNFLT) in primary open-angle glaucoma (POAG) patients after IOP reduced can provide objective evidence for evaluating the effect of lowing-IOP on the function of optic nerve.Objective The present study was to evaluate the change of optic disc parameters and RNFLT in POAG patients after trabeculectomy,and analyze the affecting factors of image parameters.Methods A serial case-observational study was adapted.Forty eyes of 39 patients with POAG underwent trabeculectomy were recruited in the study.IOP was examined and perimetry was performed before operation and 2 weeks,1 month,3 months,6 months and 1 year after surgery.Optical parameters and RNFLT were measured using Heidelberg retina tomography (HRT) and optical coherence tomography (OCT) in above-mentioned time points.The correlations between lowing-IOP range or disease severity and optical disc parameters or mean RNFLT (mRNFLT) were analyzed by Pearson linear correlation.Results Mean IOP of the 40 eyes was (32.77±8.64) mmHg before operation and (12.45 ±3.65) mmHg,(13.05±3.90) mmHg,(13.42± 3.33) mmHg,(14.22± 2.60) mmHg and (14.74±2.46)mmHg 2 weeks,1 month,3 months,6 months and 1 year after operation,with a significant difference among various time points (F=13.73,P =0.00).However,no significant difference was seen in the mean defect of perimetry among the different time points (F=1.02,P=0.41).The cup area (CA),cup/disc area ratio (C/DAR),cup volume (CV),mean cup depth (MCD),cup shape measurement (CSM),horizontal C/D,vertical C/D,rim area (RA),rim/disc area ratio (R/DAR),height variation contour (HVC),rim volume (RV),mRNFLT,RNFL cross sectional area (RNFLA) were gradually improved after operation in comparison with before operation.One year after operation,RV,CSM,mRNFLT,RNFLA were still increased,but vertical C/D was reduced after operation than that of before (P＜0.05).No significant differences were found in the whole mRNFLT and superior quadrant mRNFLT,inferior quadrant mRNFLT,nasal quadrant mRNFLT and temporal quadrant mRNFLT among before and after operation (F=1.63,P=0.16; F=0.51,P=0.77; F=1.44,P=0.20;F=1.02,P=0.32; F=1.31,P=0.30).Positive correlations were found between lowing-IOP range and the improvement of RV,CSM,vertical C/D (r =0.45,P =0.02; r=0.41,P=0.04; r=0.58,P=0.00),and negative correlations were seen between absolute value of MD and the improvement of RV,CSM 1 year after operation (r=-0.43,P=0.03; r=-0.62,P=0.00).Conclusions Reduction of IOP after trabeculectomy results in the reversal of optic disc parameters.The improvement of the optic disc parameters may be a protective factor for progression of glaucomatous optical nerve damage.

Objective 99Tcm-4,9-diaza-3,3,10,10-tetramethyldodecan-2,11-dione dioxime(HL91),a new type of hypoxic agents,accumulates in tumor hypoxic tissue specifically.The aim of this study was to evaluate the value of 99Tcm-HL91 imaging in the diagnosis of bone metastasis.Methods Nineteen cases with bone metastasis(without any treatment)and 8 cases with benign lesions underwent SPECT imaging at 4 h after injection of 740 MBq of 99Tcm-HL91 along with 99Tcm-methylene diphosphonic acid(MDP)imaging.Regions of interest(ROIs)were drawn in tumor tissue and contralateral normal tissue respectively,and the radioactivity ratios of tumor-to-normal(T/N)were calculated.The t-test was used for data analysis with SPSS 11.0.Results There were visible uptake of 99Tcm-HL91 in 79 out of 85 focuses in 19 patients of bone metastasis;however,there was no obvious uptake of 99Tcm-HL91 in 12 focuses of 8 patients of benign lesions.Significant difference existed between the T/N values of malignant(1.877±0.288)and benign lesions[(0.735±0.236);t=13.065,P＜0.05].However,the T/N value of bone metastasis from lung cancer did not differ with that from prostate cancer(1.915±0.344 and 1.825±0.175,respectively;t=1.378,P＞0.05).Conclusion The results indicated that 99Tcm-HL91 was useful in diagnosing the malignant and benign bone lesions.

Child, Preschool ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; Sturge-Weber Syndrome ; diagnosis ; Tomography, X-Ray Computed

Objective To investigate the role and mechanism of platelet in the development of salt-sensitive hypertension.Methods 25 Dahl salt-sensitive rats (Dahl SS) were divided into three groups: low-salt diet (0.12% NaCl, LS), high-salt diet (8%NaCl, HS) and high-salt diet + platelet inhibitor (8%NaCl+busulfan, HS+bus).Blood pressures were measured by tail-cuff method.After six weeks, animals were sacrificed.Platelet p-selectin expression, platelet cytosolic Ca2+ concentration, platelet-leukocyte aggregation (PLA) in peripheral blood, and immune cells infiltrated on aortic walls were assessed by flow cytometry, and serum IL-6 level was tested by ELISA in vivo.Platelets purified from SD rats were treated with normal salt (0.9%NaCl) and high salt (1.3%NaCl), then the cytosolic Ca2+ concentration and p-selectin expression of platelet were detected.Results We found that Dahl SS rats with high-salt diet, relative to low-salt diet, presented with high blood pressure and increased the ratio of platelet p-selectin expression, Ca2+ concentration.IL-6 level and PLA in peripheral blood, and the number of infiltrated immune cells on aortic walls were also significantly elevated in high-salt diet group.The whole events were ameliorated by the platelet inhibitor busulfan.Cytosolic Ca2+ concentration and p-selectin expression were also increased in purified platelets treated with high salt than those treated with low salt (P < 0.05).Conclusions Our findings suggest that high salt induced platelet activation with increased Ca2+ concentration may play an important role in the development of salt-sensitive hypertension via vascular inflammation.However, the detailed mechanisms of platelet activation and development of high blood pressure via inflammation induced by high salt intake remain to be determined.

Background Retinal retinoic acid (RA) plays an important role in the formation of the lensinduced myopia.However,it is not clear how RA transfer the myopic signal to choroid throughout the retinal pigment epithelium (RPE) barrier.Objective The aim of this study was to investigate the effect of all-trans retinoic acid (atRA) on the barrier of RPE in lens-induced myopic eye of guinea pig.Methods Thirty left eyes of 30 21-dayold clean guinea pigs were randomized into normal control group and the model group.The models of out of focus were induced by covering of-6.00 D concave lens on the left eyes for 15 days.Radius of corneal curvature was measured using corneal curvimeter,and diopeter of the guinea pig was examined by mydriatic optometry.The length of ocular axis was detected by A-sonography.The animals were sacrificed and the retinas of the left eyes were isolated for the culture and passage of RPE cells.The third generation of cells were incubated Millcell-PET microporous film,and atRA at the concentration of 1 × 10-6,1 × 10-7,1 × 10-8 and 1 × 10-9 mol/L was added to the micropore respectively for 12 hours,and the micropores with equal-solvent served as negative control group.Methyl thiazolyl tetrazolium (MTT)colorimetric method was used to detect the survival rate of the cells.Subsequently,the transepithelial electrical resistance (TER) of the monolayer cells was determined with CN10-EVOM2 resistance measuring meter.The vesicular transport change of RPE membrane in different groups was evaluated by FM1-43 fluorescence staining.Results The mean diopter was (-2.20±0.95) D in the models,and that in the controls was (+ 1.15 ±0.30) D,with a significant difference between them (t =14.57,P＜ 0.01).The axial length was (8.24 ± 0.09) mm in the models and it was significantly longer than (7.81±0.05) mm in the controls (t=17.20,P＜0.01).RPE cells grew well to form a monolayer in Millcell culture pool after one week.After 24 hours of the atRA treatment,the survival rate of RPE cells reduced gradually with the increase of atRA concentration with the highest rate in the 1 × 10-9 mol/L atRA group (93.3 ％) and followed by the 1 × 10-8 mol/L atRA group (88.2％).More than half of the cells dead in the 1 × 10-6mol/L and 1 × 10-7mol/L atRA groups (53.8％ and 47.1％).Significant differences in the TER value and fluorescence staining intensity of the cells were seen among the various groups (F =43.89,P =0.00 ; F =26.13,P =0.00),with the maximal values in the 1 × 10-8mol/L atRA group.The FM1-43 fluorescence located on the cellular membrane and cytoplasm.Conclusions AtRA can increase the functional state of tight junction and vesicular transport,which regulated the RPE cell barrier in the guinea pig.