1.IMPROVEMENT OF NIGERICIN PRODUCTION IN STREPTOMYCES HYGROSCOPICUS NND-52 BY COMBINATION MUTANT
Lin XIAO ; Wei-Yi HUANG ;
Microbiology 1992;0(04):-
Based on the lethal rate, positive and negative mutation rate, the optimal doses of UV, HNO2, UV + AO treating S. hygroscopicus NND-52-29 were determined. The mutant strain A19 that was obtained showed the derepres-sive property to glucose and the nigericin yield of A19 could be increased by 128%. When it was subcultured combined with natural screening, its stability was rather satisfied.
2.Genotype-specific functional differences of the hepatitis B virus X protein
Xu LIN ; Xiao XU ; Qingling HUANG
Chinese Journal of Infectious Diseases 1997;0(04):-
pcDNA3.1/Hygro(-)+pCMV?. Conclusions Transactivation competence of genotype B HBx was higher than that of genotype C HBx, while the antiproliferative and apoptosis effects of genotype B HBx was lower than of genotype C HBx. B and C genotype-specific functional differences of HBx may closely co-related with the pathogenicity of HBV.
3.Construction of suppression subtractive hybridization library of renal cell carcinoma
Junkui AI ; Lin CHEN ; Xiao HUANG
Chinese Journal of Urology 2001;0(09):-
Objective To construct a suppression subtractive hybridization (SSH) library of human renal cell carcinoma. Methods Poly A + RNA was isolated from human renal cell carcinoma (RCC) tissues and matched normal kidney tissues, respectively. Then double strand cDNA were synthesized and restricted by Rsa I.RCC cDNA were divided into two groups and ligated with either adaptor 1 or adaptor 2.After RCC cDNA hybridized with normal kidney cDNA twice and underwent nested PCR,the PCR products were cloned into pT Adv vector and transformed E.coli TOP10F′.Some positive clones randomly picked up were digested and sequenced. Results The SSH library contained 414 positive clones. Random analysis of 265 clones with enzyme restriction showed that 246 clones contained cDNA fragments which were distributed mainly between 300~900 bp. Among 40 arbitrary clones derived from the above 246 clones, No.170 clone is a previously unknown sequence and the other 39 clones were derived from 35 known genes. Conclusions The quality of the SSH library of human RCC is reliable and its construction would lay the foundation for further screening differentially expressed genes in RCC.
5.Expression of Notch1 protein in induction of embryonicstem cells into nerve cells
Ying XIAO ; Qi WANG ; Shibo TANG ; Bing HUANG ; Shaofen LIN
Chinese Journal of Tissue Engineering Research 2008;12(25):4967-4970
BACKGROUND: Embryonic stem cells (ESCs), the seed cells of all mature cells in vivo, are useful tools for nerve transplantation and developmental gene function research. Notch1 signaling pathway is the key pathway to control the ordered neural development and differentiation of many kinds of neural cells, however, there is no report on the dynamic expression of Notch1 signal during the ESC differentiation to date. OBJECTIVE: To investigate the expression of Notch1 protein, transmembrane signal transduction molecule, during directional differentiation of embryonic stem cells into neural cells. DESIGN, TIME AND SETTING: Cell research was carried out between October 2003 and October 2004 at Zhongshan Ophthalmic Center, SUN Yat-sen University, Guangzhou, Guangdong Province, China. MATERIALS: BALB/C mouse embryonic stem cell line Ⅵ (passage 11)was obtained from experimental animal center of SUN Yat-sen University, provided by professor Huang Bing. ESC culture medium was high-glucose DMEM medium with 20% bovine serum and 106 IU/L mouse leukemia inhibitory factor. Induced differentiation medium was high-glucose DMEM medium with 20% fetal bovine.serum and 5×107 mol/L retinoid acid(RA). METHODS: Passage 11 ESCs were resuscitated and incubated by ESC culture medium in incubator at 37℃ with 5% CO2. Passage 11 ESCs were subcultured after 2 or 3 days and RA was added into medium to induce differentiation. Three time points for observation were established: induced for 1, 5 and 9 days. MAIN OUTCOME MEASURES: Morphological changes were observed under inverted phase contrast microscope, MAP-2 antigen expressed in differentiated cells was detected by immunofluorescence method. Immunocytochemistry, Western Blot, flow cytometry assay were used to investigate the Notch1 protein expression. RESULTS: ESCs presented clone-like growth. After induced by RA for 9 days, single neural network was achieved around most of the cell clusters. With the prolongation of induction, MAP-2 positive neural cells increased gradually. Almost all ESC clones expressed Notch1 protein strongly or positively, but Notehl protein expression decreased gradually after induced differentiation (P < 0.01). CONCLUSION: Notch1 signal shuts off progressively during induction of ESCs into neural cells, which suggests Notch1 may play an important role in the differentiation of ESCs into neural cells.
7.Evaluation of non-invasive ventilation in the treatment of chronic obstructive pulmonary disease complicated with typeⅡ respiratory failure
Zhihua HUANG ; Xiao LIN ; Yongxu JIN ; Biying WANG
Clinical Medicine of China 2008;24(6):545-547
Objective To investigate the clinical significance of BiPAP mechanical ventilation in the treatment of chronic obstructive pulmonary disease(COPD)with type Ⅱ respiratory failure.Methods A total 56 patients suffering from respiratory failure due to exacerbation of COPD were randomly divided into treatment group (BiPAP plus routine therapy)and control group(routine comprehensive therapy).Blood gases,respiratory rates,heart rates,scores of the activity of accessory respiratory muscles,incubation rate,fatality rate were observed.Results In the treatment group,PO2 greatly increased,PCO2 greatly decreased,pH improved significantly,and respiratory rate,heart rate and scores of the activity of accessory respiratory muscles greatly decreased.The incubation rate and the fatality rate were significantly lower in the treatment group than those in the control group(P<0.05).Conclusion BiPAP mechanical ventilation plus routine therapy on COPD with type Ⅱ respiratory failure can improve the curative effects,lessen respiratory muscle fatigue,and decrease the need for incubation and fatality rate.
8.The correlation study of fibroblast growth factor 23 and chronic heart failure
Yun RUAN ; Xiufang LIN ; Xiaoliang WEI ; Hongkai XIAO ; Yin HUANG
Chinese Journal of Postgraduates of Medicine 2014;37(7):34-37
Objective Through the correlation study of fibroblast growth factor 23 (FGF-23) and chronic heart failure to investigate the pathogenesis of chronic heart failure and provide a new method for chronic heart failure diagnosis.Methods One hundred and twenty-eight chronic heart failure patients (chronic heart failure group) were involved in this study.According to the level of left ventricular ejection fraction (LVEF),they were divided into LVEF slightly lowing group (LVEF 40%-50%,50 patients),LVEF moderately lowing group (LVEF 30%-39%,35 patients),LVEF severely lowing group (LVEF <30%,43 patients).Fifty healthy people was as control group.The level of FGF-23,parathyroid hormone (PTH),creatinine (Cr),urea nitrogen (BUN),blood calcium,blood phosphorus,N-terminal pro-B-type natriuretic peptide (NT-proBNP) were detected.The patients in two groups were performed color Doppler ultrasonography.Results The level of FGF-23,blood phosphorus,PTH,left ventricular mass index (LVMI),NT-proBNP in chronic heart failure group were significantly higher than those in control group [68.44(55.85-94.73) ng/L,34.18(30.57-38.87) ng/L,(1.13 ± 0.13) mmol/L vs.(1.02± 0.12) mmol/L,(15.51 ± 3.99) ng/L vs.(9.97 ± 0.89) ng/L,(112.27 ± 52.02) g/m2 vs.(71.37 ± 12.95) g/m2,(6 265.3 ± 15 991.6) ng/L vs.(76.12 ± 51.80) ng/L](P < 0.01).The level of blood calcium,glomerular filtration rate (GFR) in chronic heart failure group were significantly lower than those in control group [(2.28 ±0.16) mmol/L vs.(2.48 ±0.13) mmol/L,(78.28 ± 14.20) ml/ (min ·1.73 m2) vs.(85.03 ± 14.44)ml/ (min·1.73 m2)] (P < 0.01).Spearman correlation analysis showed that FGF-23 had positive correlation with age (r =0.256,P <0.01),blood phosphorus (r =0.326,P <0.01),PTH (r =0.584,P <0.01),NT-proBNP (r =0.799,P < 0.01),LVMI (r =0.540,P < 0.01),and had negative correlation with blood calcium (r =-0.308,P < 0.01),GFR(r =-0.527,P < 0.01).The level of FGF-23 was increased when LVEF reduced.Conclusions It has significant correlation between the level of FGF-23 and the degree of chronic heart failure.It suggests that the level of FGF-23 can evaluate the myocardial systolic function and ventricular remodeling.
9.Exploration of Rational Ethylparaben Contents in Chloramphenicol Eye Drops
Huang XIAO ; Jiheng LIN ; Wansheng CHEN ; Shihong MA ; Changqin HU
China Pharmacist 2014;(5):785-788
Objective: To study whether domestic chloramphenicol eye drops with different ethylparabenin content meet the re-quirements in Chinese Pharmacopoeia. Methods:Antimicrobial effect test was used to examine the antimicrobial effect of the different eye drops. Results:The antimicrobial effect of the eye drops was in compliance with the requirements in the pharmacopoeia. Conclu-sion:The ethylparabenin concentration in the eye drops is higher than necessary. Boric acid and borax not only can adjust pH, but also show antimicrobial effect.
10.Neural network injury and motor functional parameters in subacute stroke patients using diffusion tensor imaging
Xiang XIAO ; Le LI ; Yanchun LV ; Qiang LIN ; Dongfeng HUANG
Chinese Journal of Tissue Engineering Research 2014;(15):2421-2426
BACKGROUND:The interaction of neural network and motor function in post-stroke brain tissue remains unclear.
OBJECTIVE:To observe neural network impairment fol owing subacute stroke by using diffusion tensor imaging, and to investigate the relationship with neurological defects and motor dysfunction.
METHODS:A total of 19 patients after subactue stroke and 20 healthy adults were examined with diffusion tensor imaging. The fol owing parameters were compared:fractional anisotropy, apparent diffusion coefficient, asymmetry indices of fractional anisotropy and apparent diffusion coefficient. The neurological defect and motor function were evaluated with the corresponding scales. The 10-meter walking speed was measured. The correlation of diffusion tensor imaging parameters with the scale scores and 10-meter walking speed was analyzed.
RESULTS AND CONCLUSION:The stroke group exhibited reduced fractional anisotropy value asymmetry and fractional anisotropy value in bilateral posterior limbs of the internal capsule. Apparent diffusion coefficient value asymmetry and apparent diffusion coefficient value in the posterior limb of the internal capsule were lower than control unaffected side (P<0.05). Apparent diffusion coefficient value and apparent diffusion coefficient value asymmetry in posterior limb of the internal capsule showed a strong negative correlation with Fugl-Meyer assessment scores of the lower extremities (P<0.05). Diffusion tensor imaging parameters is closely linked with motor dysfunction of the lower extremities in subacute stroke patients. Local stroke lesion-caused neurological defect is the leading cause of motor dysfunction of the lower extremities.