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The quantification of apoptotic cells is an integral component of many cell-based assays in biological studies. However, current methods for quantifying apoptotic cells using conventional random cultures have shown great limitations, especially for the quantification of primary neurons. Randomly distributed neurons under primary culture conditions can lead to biased estimates, and vastly different estimates of cell numbers can be produced within the same experiment. In this study, we developed a simple, accurate, and reliable technique for quantifying apoptotic neurons by means of micropatterned cell cultures. A polydimethylsiloxane (PDMS) microstencil was used as a physical mask for micropatterning cell cultures, and primary granular neurons (GNs) were successfully cultured within the micropattern-confined regions and homogeneously distributed over the entire field of each pattern. As compared with the conventional method based on random cultures, the micropatterned culture method allowed for highly reproducible quantification of apoptotic cells. These results were also confirmed by using GNs derived from mice with neurodegeneration. We hope that this micropatterning method based on the use of a PDMS microstencil can overcome the technical obstacles existing in current biological studies and will serve as a powerful tool for facilitating the study of apoptosis-involved diseases.  相似文献   
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Seung‐Ho Kang 《Biometrics》2015,71(1):274-277
EDITOR: TAESUNG PARK Randomized Response‐Adaptive Designs in Clinical Trials
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We report the preparation of stable dispersion of multiwalled carbon nanotubes (MWCNTs) using carminic acid (CA) as a dispersing agent. The transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM) results confirmed that MWCNT is well dispersed in CA aqueous solution and CA has been well adsorbed at MWCNT walls. Fourier transform infrared (FTIR) and UV-vis absorption spectra results also confirmed the adsorption of CA at MWCNT. To develop a highly selective amperometric biosensor for H(2)O(2) and iodate, the model enzyme catalase (CAT) was immobilized at CACNT modified glassy carbon electrode surface. The immobilized CAT exhibits well defined quasi reversible redox peaks at a formal potential (E°') of -0.559V in 0.05M pH 7 phosphate buffer solution (PBS). The proposed CAT/CACNT biosensor exhibits excellent amperometric response towards H(2)O(2) and iodate in the linear concentration range between 10μM to 3.2mM and 0.01-2.16mM. The sensitivity values are 287.98μAmM(-1)cm(-2) and 0.253mAmM(-1)cm(-2), respectively. Moreover, the developed CAT biosensor exhibits high affinity for H(2)O(2) and iodate with good selectivity.  相似文献   
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