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91.
92.
Wing-Sze Ho Han-Ming Gan Kien-Pong Yap Ganeswrie Balan Chew Chieng Yeo Kwai-Lin Thong 《Journal of bacteriology》2012,194(23):6691-6692
Escherichia coli is an important etiologic agent of lower respiratory tract infections (LRTI). Multidrug-resistant E. coli EC302/04 was isolated from a tracheal aspirate, and its genome sequence is expected to provide insights into antimicrobial resistance as well as adaptive and virulence mechanisms of E. coli involved in LRTI. 相似文献
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Histone and casein kinases of lactating bovine mammary gland 总被引:1,自引:0,他引:1
95.
Bethany M. Henrick Lucie Rodriguez Tadepally Lakshmikanth Christian Pou Ewa Henckel Aron Arzoomand Axel Olin Jun Wang Jaromir Mikes Ziyang Tan Yang Chen Amy M. Ehrlich Anna Karin Bernhardsson Constantin Habimana Mugabo Ylva Ambrosiani Anna Gustafsson Stephanie Chew Heather K. Brown Petter Brodin 《Cell》2021,184(15):3884-3898.e11
96.
Lei Li Ryan Z.L. Lim Lawrence S.U. Lee Nicholas S.Y. Chew 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(8):1790-1800
Background
HIV infection and/or the direct pathogenic effects of circulating HIV proteins impairs the physiological function of mesenchymal stem cells (MSCs), and contribute to the pathogenesis of age-related clinical comorbidities in people living with HIV. The SDF-1/CXCR4 pathway is vital for modulating MSC proliferation, migration and differentiation. HIV glycoprotein gp120 inhibits SDF-1 induced chemotaxis by downregulating the expression and function of CXCR4 in monocytes, B and T cells. The influence of gp120 on CXCR4 expression and migration in MSCs is unknown.Methods
We investigated CXCR4 expression and SDF-1/CXCR4-mediated MSC migration in response to gp120, and its effect on downstream signaling pathways: focal adhesion kinase (FAK)/Paxillin and extracellular signal-regulated kinase (ERK).Results
Gp120 upregulated MSC CXCR4 expression. This potentiated the effects of SDF-1 in inducing chemotaxis; FAK/Paxillin and ERK pathways were over-activated, thereby facilitating actin stress fiber reorganization. CXCR4 blockage or depletion abrogated the observed effects.Conclusion
Gp120 from both T- and M- tropic HIV strains upregulated CXCR4 expression in MSCs, resulting in enhanced MSC chemotaxis in response to SDF-1.General significance
HIV infection and its proteins are known to disrupt physiological differentiation of MSC; increased gp120-driven migration amplifies the total MSC population destined for ineffective and inappropriate differentiation, thus contributing to the pathogenesis of HIV-related comorbidities. Additionally, given that MSCs are permissive to HIV infection, initial cellular priming by gp120 results in increased expression of CXCR4 and could lead to co-receptor switching and cell tropism changes in chronic HIV infection and may have implications against CCR5-knockout based HIV cure strategies. 相似文献97.
OBJECTIVE: The Singapore Breast Screening Pilot Project (SBSPP) was embarked upon (1994-1997) to determine if mammography was useful in early breast cancer detection among Asian women. PATIENTS AND MEASUREMENTS: Of 28 231 women screened, fine needle aspiration cytology (FNAC) was performed in 232 individuals as part of the triple assessment. RESULTS: Absolute and complete sensitivities for the diagnosis of carcinoma were 46.7% and 82.2%, respectively, based on the results of FNAC. Specificity was 63.3%. The inadequate rate was 31%. Five women who were considered cancer-free on triple assessment and, in two cases open diagnostic biopsy during the SBSPP, subsequently developed breast cancer after a median follow-up of 6 years. CONCLUSION: Although our FNAC results compared relatively well with international standards, they reflect a small cohort, and may face additional difficulties in a larger programme. 相似文献
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To maintain protein homoeostasis, animals have developed stress response pathways such as the ubiquitin proteasome system (UPS). Joshi and colleagues have demonstrated that in Caenorhabditis elegans, dopamine release from neurons acts on receptors in the epithelia to modulate protein turnover, by controlling the expression of regulators of the xenobiotic stress response. Dopamine receptor mutants challenged with pathogenic bacteria were defective in protein turnover and were also more sensitive to infection thus highlighting a role for monoamine signalling in innate immunity and stress responses. 相似文献