Extraction, separation, and in vitro dissolution of HgS micro & nano-particles from Mongolian medicine Menken Usu / 中草药

Objective To study the extraction, separation, and in vitro dissolution method of HgS micro & nano-particles from Mongolian medicine Menken Usu. Methods The Soxhlet extraction method was used to investigate the sulfur from Menken Usu effectively, and the optimum time of extraction was determined by investigating the influence of different extraction time on the extraction rate of sulfur in the Menken Usu. Then, the mercuric sulfide particles were separated by differential centrifugation. The mercuric sulfide micro & nano-particles with different particle sizes can be obtained by controlling the concentration of PVP, molar ratio, centrifuge speed, and other factors. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to analyze the morphology and composition of the particles. Using dithizone colorimetric method to determine and compare the dissolution of HgS particles with different sizes, Menken Usu original herbs, and Menken Usu-18 in simulated human gastric and small intestinal. Results The SEM results showed that the obtained six mercuric sulfide particle samples have a uniform size distribution: Uniform size were 2 000-4 000, 800-2 000, 200-800, 80-200, 50-80, and 20-50 nm. The main components in the extracted samples were α-HgS and β-HgS. As the particle size of HgS gradually became smaller, the dissolution of mercury was increased, which indicated that the size of HgS particle was inversely related to the dissolution of mercury. At the same time, the dissolution of mercury is also affected by sulfur, pH, and compounds. Conclusion This is a simple and efficient method for the separation of mercuric sulfide particles, and provides the basis for the pharmacokinetics and pharmacological study of mercuric sulfide nanoparticles with different particle size.

Trypanosoma evansi is alike to Trypanosoma brucei brucei in the subcellular localisation of glycolytic enzymes

Trypanosoma evansi, which causes surra, is descended from Trypanosoma brucei brucei, which causes nagana. Although both parasites are presumed to be metabolically similar, insufficient knowledge of T. evansi precludes a full comparison. Herein, we provide the first report on the subcellular localisation of the glycolytic enzymes in T. evansi, which is a alike to that of the bloodstream form (BSF) of T. b. brucei: (i) fructose-bisphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), hexokinase, phosphofructokinase, glucose-6-phosphate isomerase, phosphoglycerate kinase, triosephosphate isomerase (glycolytic enzymes) and glycerol-3-phosphate dehydrogenase (a glycolysis-auxiliary enzyme) in glycosomes, (ii) enolase, phosphoglycerate mutase, pyruvate kinase (glycolytic enzymes) and a GAPDH isoenzyme in the cytosol, (iii) malate dehydrogenase in cytosol and (iv) glucose-6-phosphate dehydrogenase in both glycosomes and the cytosol. Specific enzymatic activities also suggest that T. evansi is alike to the BSF of T. b. brucei in glycolytic flux, which is much faster than the pentose phosphate pathway flux, and in the involvement of cytosolic GAPDH in the NAD+/NADH balance. These similarities were expected based on the close phylogenetic relationship of both parasites.

Proteomic Characterization of Human Erythrocyte 20S Proteasome and Analysis of Species-dependent 20S Proteasome Heterogeneity / 分析化学

A method was developed for purification of 20S proteasome (20S core particle, CP) by combining differential centrifugations with nondenaturing polyacrylamide gel electrophoresis (native-PAGE), irrespective of species origins of CPs. CP purified from human erythrocytes was subjected to proteomic analysis by two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), revealing 33 spots of subunit isoforms with different molecular weights and isoelectric points, more than 14 constituent subunits. Furthermore, other four CPs were purified from yeast, mouse liver, two pancreatic cancer cell lines SW1990 and PANC-1 using this method mentioned above, and subjected to proteasome heterogeneity analysis by native/SDS-PAGE (native/sodium dodecyl sulphate polyacrylamide gel electrophoresis), together with CP from erythrocytes. The method described acts as a rapid and effective tool for CP isolations, and the results obtained may be served as a footstone for the investigations of species-dependent proteasome heterogeneity.

Differential Proteins of Liver Revealed with a Combined Technology of both Differential Centrifugation and Proteomics in Paralichthys Olivaceus Under Stress of Cadmium Salt / 分析化学

Both total proteome and differential proteins were effectively extracted, separated and selected by a combined approach of both differential centrifugation and 2D-PAGE in liver of Paralichtys olivaceus( POL) under the stress of cadmium chloride as an artificial pollution source. Approximately 800 spots for extraction of whole protein separated with 2D-PAGE were obtained by direct lysis in the POL. In addition, approximately 11 differential proteins in POL were also obtained under the stress of cadmium chloride. The differential centrifugal were used to prepare three sedimentation and a plasmolysis proteins, called POL component Ⅰ, POL component Ⅱ, POL component Ⅲ, and POL component Ⅳ(plasmolysis protein), respectively. Total protein spots for each gel were calculated to have 380, 550, 500, and 850, respectively, approximately 2280 spots in sum, while total spots are much higher than those by direct lysis approach. Using the comparison method, approximately 54 differential proteins in POL were obtained by a combined technology of both differential and two dimensional polyacylaminde gel electrophoresis(2D-PAGE) methods under the stress of cadmium chloride. In addition, these differential proteins can be further identified by peptide mass fingerprint(PMF). Here, these combined techniques can be effectively used to extract, separate and identify the whole proteins and the differential proteins including protein markers in the biological tissue.

ISOLATION OF ACIDOPHILIC AND ACIDODURIC STREPTOMYCETES USING DISPERSION AND DIFFERENTIAL CENTRIFUGATION APPROACH / 微生物学通报

Technological improvement for microorgnism isolation is important since isolation provides substantial materials for the exploitation of new microbial resources. In this study, a new approach, dispersion and differential cetrifugation (DDC), was applied in the isolation of acidophilic and acidoduric streptomycetes from 12 acid soil samples. Contrast with traditional method, the new approach yielded satisfying results with 2 - 20 times isolation efficiency and good selectivity. 45 representatives out of 249 streptomycetes isolates, which belonged to 12 color groups, showed morphology and cell wall type consistent with streptomycetes. The optimum pH range for their growth were between pH 4.5 - 5.5. It is proved that we succeeded in the rare-streptomycetes isolation using DDC approach.

Purification of treponema pallidum from rabbit testicular tissue / 대한피부과학회지

There are several different methods of purifying Treponema pallidum(TP) from rabbit testicular tissue. Among them, we compared the use of differential centrifugation, which has been most widely used, to Percoll density gradient centrifugatian, a newly applied method, in purifying TP from rabbit testicular tissue by checking the protein concentration of the TP suspension, hemagglutination assay using sheep erythrocytes sensitized by TP, IgM-TP-enzyme-linked immunosorhent, assay(IgM-TP-ELISA) and eJect,ron microscopic observation. The protein concent,ration af TP antigen suspension (2x10(8)TP/ml) purified by Percoll density gradient centrifugation (lower band) was the lowest (129.0pg/ml) when compared to those purified by differential centrifugation (324.0pg/ml) and Percoll density gradient centrifugatian (upper band) (560.2pg/ml). Sheep erythrocytes sensitized by TP purified by Percoll density gradient centrifugation(lower band) showed the same resiilts as those using a commercii1 TPHA kit when tested with positive and negative control sera. The sensitivity and specificity of the IgM-TP-ELISA were 88.5%(23/26') and 86.4%(19/2Z) respectively using TP as an antigen purified by differential centrifugation. The rates were 96.29% (25/26) and 95.5%(2l/22) using TP purified by Percoll density gradient centrifugation. As shown by the electron microscopy, T. pizllida purified by clifferential centritugation and Percoll density gradient centrifugatiori were structurally unaltered, and Percoll-purified TP contained much less tissue debris than TP prepared by differ ential centrifugation. Therefor e, Percoll density gradient centrifugation is considered to be a better method of purifying TP from rabbit testicular tissue when compared to differential centrifugatian, as a matter of fact, Perrol1 density gradient centrifugation has been applieci successfully in the study of the physiology, recombinant DNA techniques, and antigenic structure of TP and to the preparation of the antigen for the FTA-ARS and TP-ELISA