Pathogenesis and prevention tactics of aspirin resistance / 中西医结合学报

Aspirin (acetylsalicylic acid) is a nonsteroidal anti-inflammatory drug. Despite its wide uses for more than 100 years, knowledge about mechanism of action and therapeutic issues of aspirin are still under discussion. The use of aspirin has been changed from an analgesic, anti-pyretic and anti-inflammatory agent to an anti-thrombotic agent, especially in secondary prevention of cardiovascular events. Aspirin has reduced the risk of cardiovascular events by 25%. However, the phenomenon of "aspirin resistance" has been described that in 5%-60% of patients aspirin may not achieve adequate efficacy of suppressing platelet activity. The convinced causes of this phenomenon are still unknown. It is probably due to drugs interaction, inadequate dosage and so on. By far the existing studies of aspirin are insufficient to explain all phenomena of aspirin resistance. And the results are not always uniform about the same research. Therefore, the characteristics in different population with aspirin resistance may account for the complexity. It is unrealistic to elucidate all aspirin resistance by only one pathway. More studies are required to investigate the mechanisms in different population respectively. According to the theory of traditional Chinese medicine and the trait of cardiovascular disease, which often relapses and has a long history, aspirin resistance should be considered as collaterals disease. It can be treated with aspirin and traditional Chinese drugs which have the power to strengthen body resistance, reduce phlegm, remove blood stasis and toxic materials from meridians. The problem of aspirin resistance might be solved by this way, because the traditional Chinese medicine has the superiority of selecting appropriate therapeutic methods based on syndrome differentiation for different population and regulating the whole body's function. Subsequently, cardiovascular disease might be effectively prevented.

Comparative Proteomic Analysis of the Promastigotes and Amastigotes of Leishmania donovani / 中国寄生虫学与寄生虫病杂志

Objective To explore the protein profile and identify developmentally regulated proteins of the promastigotes and axenic amastigotes with comparative proteomics technique.Methods The total proteins of promas-tigotes and axenic amastigotes of Leishmania donovani SC6 strain were separated by two-dimensional electrophoresis(2-DE) in a broad pH range(3-10) , and the gel was stained with Coomassie blue.The images were analyzed by PDQuest 1.0 software, and the major developmentally regulated proteins were identified by electrospray mass spectrometry.Results Approximately 700 protein spots were revealed in equivalent proteins of the promastigotes and axenic amastigotes separated by 2-DE, among which more than 90% protein spots showed equivalent quantity and distribution, with 6 proteins up-regulated and 3 proteins down-regulated in axenic amastigotes compared with promastigotes.Five of the 6 up-regulated proteins were with known function, respectively ascribed as Reiske iron-sulfur protein precursor, ?-tubulin, peroxidoxin 1, dihydrolipoamide acetyltransferase precursor, and mannose-1-phosphate guanyltransferase.Two of the 3 down-regulated proteins were identified as heat shock protein 70 and ?-tubulin.The functions of the developmentally regulated proteins were related to the carbohydrate/energy metabolism, stress response, or formation of cell membrane/cytoskeleton.Conclusion The findings demonstrate the differences in protein expression profiles between promastigotes and amastigotes.

Virulence-associated Gene Profiling of Different Leishmania spp / 中国寄生虫学与寄生虫病杂志

Objective To investigate the expression level of virulence-associated genes in promastigotes and amastigotes of different Leishmania spp.. Methods Total RNA was extracted from the promastigotes and amastigotes of Leishmania donovani, L. infantum, L. tropica, L. major and L. mexicana, and relevant strains. According to the reported gene sequences in GenBank, primers were designed in relation to the virulence-associated genes [GDP-mannose pyrophosphorylase (GDPMP), 3′a2rel-related protein (A2rel), beta-galactofuranosyl transferase (LPG1), lipophosphoglycan biosynthetic protein (LPG2), kinetoplast membrane protein 11 (KMP-11), cpc gene for cysteine proteinase (CPC), hydrophilic acylated surface protein (HASPB1), cathepsin L-like cysteine protease (CPB2), cathepsin L-like cysteine proteinase lmcpb2.8 (CPB2.8), Mr 100 000 heat shock protein (CLP b)], and control genes (alpha tubulin gene and GAPDH). Semi-quantitative RT-PCR was performed to detect expression level of these genes in promastigotes and amastigotes of different Leishmania spp. Results There was a significant difference in the expression profiles of the genes among the promastigotes and amastigotes of different Leishmania spp. The HASPB1 was detected in the amastigotes of all strains and promastigotes of L. donovani, the GDPMP, LPG1, LPG2, CPB2.8, CPB2, CPC, A2rel and CLP b were expressed in the promastigotes and/or amastigotes of the specific Leishmania spp, respectively. None of the stains carried the KMP-11 gene, whereas the amastigotes of L. donovani SC10 strain and L. major 5ASKH strain possessed CPC. Conclusion The expression profile of the virulence-associated genes shows species-specific and stage-specific differences.