Objective To establish a method to determine lead in air. Methods The filter film used to collect the lead in air was digested with acid followed by adding mixed solution of potassium ferricyanide,oxalic acid and hydrochloric acid, then double ways atomic flurescence spectrophotometry was employed to determine lead. Results The optimal concentration of hydrochloric acid, potassium ferricyanide and oxalic acid were 0.12 mol/L, 8 g/L and 0.4 g/L respectively. The detection limit of lead was 1 ?g/L, the relative standard deviation was 2.5%. The recovery rates ranged from 90% to 95%, the linar range was 10-80 ?g/L. Conclusion This method was simple, rapid, accurate and sensitive. It was suitable for determining lead in air.

α-Galactosidase A (α-Gal A ) activities in plasma and peripheral blood granulocytes of 100healthy subjects and one patient with Fabry disease was determined by means of fluorogenic substrate.The results showed that the enzymatic activities of peripheral blood granulocytes and plasma in 100 subjects were (51.97 ± 15.24)and(148.08±26.30) nmol · h-1 · ml-1 respectively.The α-Gal A activities in plasma and granulocytes were positively correlated( r=0.533,P＜0.01 ).The enzymatic activities in peripheral blood granulocytes and plasma of the patients with Fabry disease were 1.05 and 10.06 nmol · h-1 · ml-1 respectively,both much lower than those of 100healthy subjects.These results suggest that α-Gal A activity in plasma and peripheral blood granulocytes can be used for diagnosis and screening of Fabry disease.

Objective To study the preparation technique for Jiegeng Zaogan capsules (capsules of total saponins from the roots of Platycodon grandiflorum A.DC).Methods The optimal preparation technique for Jiegeng Zaogan capsules was investigated by L9(34) orthogonal test with the Platycodin D content as the observation index.Results The optimized extraction procedure was as follows:extracting for 3 hours each time and 3 times in total,adding 10-fold water,alcohol sedimentation concentration at 65 %,and alcohol sedimentation solution staying for 48 hours.Conclusion The preparation process of Jigeng Zaogan capsules is reliable with stable quality,which offers a feasible method for the industrialization production of the capsules.

AIM: To establish the method for determing four effective components in Qidan Capsules(total saponin of Radix et Rhizoma Notoginseng,total phenolic acids of Radix et Rhizoma Salviae Miltiorrhizae) by RPHPLC. METHODS: The contents of ginsenoside Rg1、ginsenoside Rb1,notoginsenoside R1 were simultaneously determined by an HPLC system with Lichrospher C18(150 mm ? 4. 6 mm,5 ?m). The mixture of acetonitrile and water was used as the mobile phase and the flow rate was 1. 0 mL/min. The detection wavelength was set at 203 nm. The content of salvianolic acid B was determined by an HPLC system with Lichrospher C18 (150 mm ? 4. 6 mm,5 ?m). The mobile phase was (formic acid-water)-(methanol-acetonitrile) = 62 ∶ 38. Formic acid-water (1 ∶ 59),Methanol-acetonitrile (30 ∶ 10),and the flow rate was 1. 0 mL/min and the detection wavelength was 286 nm. RESULTS: The linear ranges of notoginsenoside R1,ginsenoside Rg1,ginsenoside Rb1 and salvianolic acid B were 0. 472 1 - 2. 832 ?g(r = 0. 999 5),1. 734 - 10. 404 ?g (r = 0. 999 9),1. 732 - 10. 392 ?g (r = 0. 999 9),0. 4 - 4. 0 ?g (r = 0. 999 9) respectively. The average recoveries (n = 5) were 100. 32% ,99. 965% , 100. 285% and 101. 4% ,corresponding RSD were 1. 01% ,2. 53% ,2. 46% and 1. 88% respectively. CON-CLUSION: The results indicate that the HPLC method is simple,highly selective and reproducible; thus it can be used in the determination of the four components in Qidan Capsule.

Objective To investigate the possible causes of the different diagnostic sensitivity of voluntary single fiber electromyography (SFEMG) and repetitive nerve stimulation(RNS) in patients with myasthenia gravis (MG). Methods The voluntary SFEMG and RNS at low rates were recorded successively from the same extensor digitorum communis (EDC) muscle on the same day in 67 patients with MG. Results The diagnostic sensitivity of SFEMG and RNS was 92.5% and 50.7%, respectively, with the former statistically significantly higher than the later. The percentage of decrement of RNS was positively correlated with 3 SFEMG parameters, i.e. the mean jitter, percentage of abnormal pairs of potential and percentage of impulse blocking. Among the 34 cases with significant decrement on RNS, 2 had no impulse blocking and the maximum decrement reached 62%, while 33 cases with normal RNS had up to 58% of impulse blocking. Conclusion The voluntary SFEMG was more sensitive than RNS in diagnosing MG even in the same muscle. The blocking phenomenon observed in voluntary SFEMG was not completely corresponding to the decrement in RNS.The possible explanations were partly because that RNS recorded the total muscle fibers response in surface of the muscle and SFEMG examined the increasing or blocking at individual motor end-plates, and partly because that the voluntary SFEMG and RNS might explored endplates belonging to different motor units.

Efforts on directed evolution of sortase A to optimize its catalytic properties have been undertaken and shown the promise. To facilitate screening of sortase A mutants with expected catalytic properties, a novel ligation efficiency monitoring system, including reporter substrates GFP-LPETG and GGGYK-Biotin, was developed. GFP-LPETG, wild type sortase A, and a recently reported high activity sortase A mutant were prepared recombinantly from Escherichia coli BL21 (DE3). Taking advantage of the newly designed reporter system, the ligation efficiency catalyzed by wild type and mutant form of sortase A could be sensitively monitored via SDS-PAGE directly. Consistent with previous report, the mutant sortase A displayed much higher catalytic activity compared to wild type enzyme, indicating the new reporter system is easily and fast handled and sensitive. The application of this reporter system into systemic screening will facilitate future directed optimization of sortase A.
Aminoacyltransferases ; genetics ; metabolism ; Bacterial Proteins ; genetics ; metabolism ; Biocatalysis ; Biotin ; Cysteine Endopeptidases ; genetics ; metabolism ; Electrophoresis, Polyacrylamide Gel ; Escherichia coli ; Genes, Reporter ; Ligation ; Mutant Proteins ; genetics ; metabolism

BACKGROUND:Related studies have showed that poly D,L-lactide-co-glycolide can effectively package antisense oligonucleotides, smal interfering RNA, microRNA. Poly D,L-lactide-co-glycolide can better protect them against the destruction of the enzymes in vivo and have slow the drug release. Therefore, the number of drug administration can be reduced to achieve a long-term and effective therapeutic effect. ＜br> OBJECTIVE:To prepare poly D,L-lactide-co-glycolide-CXCR4-miRNA-nano-particles and to research the characteristics of the prepared nanoparticles. ＜br> METHODS:Poly D,L-lactide-co-glycolide-CXCR4-miRNA nanoparticles were prepared by double emulsion-evaporation process. Ultraviolet spectrophotometry was utilized for measurement of encapsulation efficiency and drug-loading rate, observing the shape of nanoparticles by transmission electron microscope, and measuring the size and distribution of nanoparticles by laser particle size analyzer. Sustained-release characteristics of nanoparticle suspension were observed in phosphate buffer. ＜br> RESULTS AND CONCLUSION:The prepared nanoparticles were spherical-shaped, smooth, evently distributed and inadhesive. The particle size was mainly distributed within 143-502 nm, with an average diameter of 280 nm. The average drug loading was (0.515±0.023)%, the average encapsulation ratio was 50.2%and difference between batches was smal . The nanoparticles could slowly release in vitro and the process initial y experienced the fast-release stage, and then reached a basical y stable platform stage at day 14. These finding indicate that the process to prepare poly D,L-lactide-co-glycolide CXCR4-miRNA-nanoparticles by double emulsion-evaporation is simple. The prepared nanoparticles are wel targeted and exhibit sustained-release effects.

AIM To investigate the effects of D galactose on bone contents of hydroxyproline(HOP), calcium, microelements and activities of antioxidation in mice. METHODS Twenty female kunming mice at three months of age were used in this study. D galactose at dose of 1 g?kg -1 ?d -1 was given subcutaneous injection daily to the mice for 42 days. The right femurs were collected to determine the bone dry weight, bone hydroxyproline content, bone calcium, and bone microelements. The activities of catalase (CAT), glutathione peroxidase (GSH Px) and superozide dismutases (SOD) in blood, and contents of methylenedioxyamphetamine (MDA) in serum, lipofuscin in liver were determined. RESULTS The bone dry weight, hydroxyproline, calcium of bone decreased significantly in D galactose treaded group(compared with control group, P

Objective To analyze the MRI characteristics of cavernous angioma of the epidural space in spine.Methods MR imaging features of cavernous angioma of epidural space in 3 cases confirmed by surgery-pathology were analysed with literature review . Results Among the three cases,the tumors located in the lumbar spine in one and in the thoracic spine in 2.The tumors were all at posterior to the spinal cord and shuttle-shaped,the major axis was consistent with the spinal ordinate axis,the corresponding plane spinal cords were compressed and resulting in distortion and shift.The tumors were high signal intensity on T_2WI,and obviously homogeneous enhanced after Gd-DTPA administration. Conclusion MRI examination is the best method to diagnose this kind of disease.

Background and purpose:Arsenic trioxide(As_(2)O_(3)) injection actually has an effect on solid tumors such as hepatoma in the clinic.In order to find out its mechanism of action,we studied the action of arsenic trioxide injection on angiogenesis of chick embryo chrioallantoic membrane(CAM).Methods:The effect of arsenic trioxide injection on angiogenesis was investigated by CAM model and computer image analysis.Results:Administered at three different concentrations of arsenic trioxide injection at 10,20 and 40,3 days later,the vessel area were 25.66%?4.17%,24.74%?2.54% and 21.51%?6.70%,respectively.Compared to the NS control group(vessel area was 30.68%?(4.64%)),there was an obvious difference(P0.05 among the three different concentration groups).Conclusions:arsenic trioxide injection has a strong inhibitory effect on angiogenesis,which may be used in suppressing cancer angiogenesis.