Does hoechst 33342 stain only live cells?5 answersHoechst 33342 (H33342) is commonly used to stain DNA in living cells. While traditionally believed to be suitable only for endpoint analyses due to cytotoxicity concerns, recent studies challenge this notion. Optimized exposure parameters allow for Hoechst staining in live cells without significant cytotoxic effects at concentrations between 7 and 28 nM. Additionally, Hoechst 33342 can visualize neurites of dorsal root ganglion cells when fixed, providing a practical and cost-effective alternative for staining. Furthermore, Hoechst 33342, in combination with Pyronin Y, enables the distinction between quiescent and proliferating cells based on DNA and RNA content, showcasing its versatility in cell analysis. Therefore, Hoechst 33342 can be used to stain both live and fixed cells, expanding its utility beyond live cell staining.
Why cell viability over 100% in AlamarBlue® assay?5 answersCell viability over 100% in the AlamarBlue® assay can occur due to factors like the presence of certain drugs affecting the assay readings or plate-to-plate variability. In the study by Dinh et al., unexpected right shifts in dose response curves were observed when testing EGFR inhibitors on lung cancer cells, which led to falsely increased readings. However, modifying the assay by removing the drug-containing medium prior to adding AlamarBlue® eliminated this issue. Additionally, Lee highlighted the cost-effectiveness and ease of the AlamarBlue® assay for screening antimicrobial activity in plant extracts against various pathogens. Furthermore, Zachari et al. emphasized the importance of proper cell culture maintenance and initial cell plating numbers to ensure accurate viability measurements in radiation response experiments using the AlamarBlue® assay.
How does DLEU2 influence on cell viability?5 answersDLEU2 plays a crucial role in influencing cell viability through various mechanisms. In the context of idiopathic pulmonary fibrosis (IPF), DLEU2 upregulation was associated with increased cell proliferation and migration. Additionally, in breast cancer, DLEU2 acted as a coactivator for HIF-1α, promoting the transcription of CKAP2, which contributed to the malignancy of cancer cells. Moreover, in the context of metabolic disorders, DLEU2 knockdown led to decreased sirtuin expression, impacting mitochondrial function and oxidative stress, ultimately affecting cell viability. Furthermore, in renal cell cancer, DLEU7-AS1, a related lncRNA, promoted cell growth and metastasis by silencing the miR-26a-5p/coronin-3 axis. These findings collectively demonstrate that DLEU2 family lncRNAs play significant roles in regulating cell viability across different cellular contexts.
How does transfection affect on cell viability?5 answersTransfection can have a significant impact on cell viability. Various factors influence this relationship, such as the type of transfection method used, the duration and intensity of electric pulses, and the composition of the electroporation medium. Studies have shown that longer electric pulses optimize transfection efficiency but may reduce cell viability, while shorter pulses can maintain viability at the cost of slightly lower transfection rates. Additionally, the choice of buffer composition plays a crucial role in cell viability post-transfection, with Mg2+-based buffers enhancing viability possibly through ATPase activation, although they may hinder transfection efficiency compared to K+-based buffers. Overall, balancing transfection efficiency with cell viability requires careful consideration of these factors to design effective and safe transfection protocols.
What are the effects of nicotine on cell viability in different cell types?5 answersNicotine exhibits diverse effects on cell viability across various cell types. Studies have shown that nicotine significantly reduces cell viability in keratinocytes, cardiomyocytes, and hepatocytes, inducing apoptotic cell death and morphological changes. In lung cancer cell lines, nicotine inhibits viability in one type while inducing proliferation in another, with varying impacts on apoptosis. Moreover, nicotine has been found to modulate inflammatory cytokine expression and induce severe cellular damage in cells infected with SARS-CoV-2, resembling pyroptosis and necroptosis. Additionally, nicotine can enhance cell viability, inhibit apoptosis, and activate specific signaling pathways in Raw264.7 and El4 cells, potentially offering protective effects against toxicity. Furthermore, nicotine has been observed to increase the viability of polymorphonuclear leukocytes and macrophages, particularly in their activated states, potentially exacerbating their deleterious effects.
How to prepare MTS solution to measure cell viability?4 answersTo prepare MTS solution for measuring cell viability, follow the protocol described by Bartz. The protocol involves using a MTS cell proliferation assay kit. Unfortunately, the specific details of the protocol are not provided in the abstract.