RESUMO
Antibacterial therapy is a global health issue. The antibiotic resistance is becoming an increasingly serious threat, which caused by misuse and overuse of antibacterial agents combined with the emergence of new resistance mechanism. The resulting infection treatment risk and incidence of the spread of disease, severe cases and deaths are increased in different degrees. With the extensive application of biomaterials and nanotechnology to biomedicine, extensive research has been conducted on antibacterial infection. With the specific physicochemical properties like optical, electric and magnetic and high penetration, inorganic nanomaterials can produce natural antibacterial effect. Nanomedicine can be designed to allow controlled drug release and targeting effect, thus demonstrated better antibacterial efficiency. In this review, the mechanism of antibacterial resistance is described, and the antibacterial infection research on inorganic nanomaterials, as well as nano-drug delivery system including liposomes, nanoparticles, dendrimers and biomimetic nanocarriers are summarized. Nanomaterials and nanotechnology offer promising strategies for the development of new agents that can improve efficacy on antibacterial infections and overcome antibiotic resistance potentially.
RESUMO
<p><b>OBJECTIVE</b>To investigate the expression of Oct4, Sox2, Nanog, SMO, beta-Catenin and Wnt5b mRNA in four hepatocellular carcinoma cell lines of SMMC-7721, Bel-7402, HepG2, MHCC-97 and normal hepatocellular cell line of L02, and to compare the response of these cell lines to all-trans retinoic acid.</p><p><b>METHODS</b>RT-PCR was used to detect expression of Oct4, Sox2, Nanog, SMO, beta-Catenin and Wnt5b mRNA in four hepatocellular carcinoma cell lines and normal hepatocellular cell line. Real time-PCR was used to quantify the expression of the genes.</p><p><b>RESULTS</b>There are different levels of expression of the stem cell-related gene in hepatocellular carcinoma cell lines and control cell line (P less than 0.05). There are significant differences in HepG2 and L-02 for the response to all-trans retinoic acid (P less than 0.05).</p><p><b>CONCLUSIONS</b>The stem cell-related genes are differentially expressed in different hepatocellular carcinoma cell lines.</p>