RESUMEN
Regenerative medicine refers to research and treatments that restore damaged tissues. It consists of three factors: cells, chemical substances, and scaffolds. One of its purposes is rejuvenation, and from this point of view, it really resembles anti-aging medicine. Recently, studies concerning stem cells such as embryonic stem cells (ES) and induce pluripotent stem cells (iPS) have made remarkable progress and seem promising, but are still far from clinical use. In contrast, we introduce a few examples of anti-aging medicine using regenerative medicine methods that have been applied successfully in clinical use such as cultured fibroblast, adipose tissue derived stem cells and platelet rich plasma (PRP), and continue researching cultured dermal papilla cells.
Asunto(s)
Envejecimiento/fisiología , Medicina Regenerativa , Fibroblastos/trasplante , Humanos , Rejuvenecimiento/fisiología , Trasplante de Células MadreRESUMEN
A DNA fragment conferring drug resistance was cloned from the chromosomal DNA of Staphylococcus aureus N315 using a drug hypersensitive Escherichia coli KAM32 as the host. Although E. coli KAM32 cells were sensitive to many antimicrobial agents, transformed cells harboring a recombinant plasmid carrying the DNA region became resistant to several structurally unrelated antimicrobial agents, such as tetraphenylphosphonium chloride, Hoechst 33342 and norfloxacin. These results suggest that the cloned DNA fragment carries a gene(s) encoding a multidrug efflux pump. We partially determined the nucleotide sequence of the cloned DNA and found the mdeA gene within it. The E. coli cells transformed with the mdeA gene showed efflux activity of Hoechst 33342. On the other hand, S. aureus cells transformed with mdeA showed elevated resistance to doxorubicin, daunorubicin, tetraphenylphosphonium chloride, Hoechst 33342, ethidium bromide and rhodamine 6G. Elevated energy-dependent efflux of ethidium was observed with transformed S. aureus. We found that the mdeA gene was expressed under normal growth conditions in S. aureus N315.
Asunto(s)
Proteínas Bacterianas/genética , Proteínas de Transporte de Membrana/genética , Staphylococcus aureus/genética , Antibacterianos/farmacología , Bencimidazoles/metabolismo , Bencimidazoles/farmacología , Clonación Molecular , ADN Bacteriano/genética , ADN Bacteriano/metabolismo , Farmacorresistencia Bacteriana Múltiple , Escherichia coli/genética , Escherichia coli/metabolismo , Etidio/metabolismo , Colorantes Fluorescentes , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rodaminas , Staphylococcus aureus/metabolismoRESUMEN
There are more than 30 genes for putative multidrug efflux pumps in the chromosome of Staphylococcus aureus. Only a few of these have been analyzed so far. Here we cloned a new gene, SA1972, using a PCR method, from the chromosome of S. aureus N315. We found that the product SA1972 could lead to elevated resistance against several antimicrobial agents such as norfloxacin, acriflavine and ethidium bromide. We designated the gene as sdrM. We observed elevated energy-dependent efflux of acriflavine in S. aureus cells introduced with the sdrM gene. We conclude that SdrM is a multidrug efflux pump belonging to the major facilitator (MF) superfamily.
