Ultrasensitive Graphene-Based Nanobiosensor for Rapid Detection of Hemoglobin in Undiluted Biofluids.

Detection of hemoglobin (Hb), a critical part of the biological system that is responsible for oxygen transportation, is of great significance on clinical diagnosis of various diseases. Particularly, time-efficient Hb detection under nanomole levels has drawn much attention in recent years. Herein, we present a graphene field effect transistor (GFET)-based aptameric nanobiosensor for rapid detection of Hb in undiluted biofluids including serum and urine and for the first time use polyethylenimine (PEI), a kind of comparatively low-cost polymer consisting of numerous amino groups, which can be directly linked with the anchor molecule without any pretreatment as the graphene surface passivation agent. Experimental results indicate the PEI-modified graphene aptameric nanobiosensor can respond to the Hb concentration change in a few minutes (6-8 min) with estimated detection limits of 10.6 fM in 1× PBS, 14.2 fM in undiluted serum, and 11.9 fM in undiluted urine, respectively. Further, considering the potential use of our sensor for implantable and wearable applications, we also examine the sensing performance of the sensor fabricated on an ultrathin flexible polyethylene terephthalate (PET) substrate. The Hb detection results are almost invariable even after 100 cycles of cyclic extension by 120% or 100 cycles of bending with a radius of 1 mm. Hence, our sensor holds great potential for accurate monitoring of nanomole levels of Hb in clinical applications.

Effect of silencing FBXO2 expression on proliferation, invasion, migration, and EMT of gastric cancer cells / 中国肿瘤生物治疗杂志

@#［摘要］ 目的：探讨F 框蛋白2（F-box only protein 2，FBXO2）基因在人胃癌细胞系中表达及其对胃癌细胞增殖、迁移、侵袭和 EMT 的影响。方法：选择胃癌细胞系MGC-803、AGS、SGC-7901、MKN-28 以及正常胃黏膜上皮细胞株GES-1，qPCR 法检测细 胞中FBXO2 mRNA表达水平。设计靶向抑制FBXO2 表达的特异siRNA，并瞬时转染MGC-803 细胞，转染siRNA无义序列的为 阴性对照。qPCR法检测转染48 h 后MGC-803 细胞中FBXO2 mRNA表达水平；用MTT法、细胞划痕愈合法、Transwell 小室法检 测降低FBXO2 表达对细胞增殖、迁移和侵袭的影响，WB 法检测细胞中EMT 相关蛋白E-cadherin、N-cadherin、vimentin 的表达。 结果：4 种胃癌细胞中FBXO2 mRNA表达水平显著高于胃黏膜上皮细胞GES-1（P<0.05 或P<0.01）。与阴性对照组相比，siRNAFBXO2 组MGC-803 细胞中FBXO2 mRNA表达下调（P<0.01），该细胞的增殖、迁移和侵袭能力受到显著抑制（P<0.05 或P<0.01）， E-cadherin 蛋白表达明显升高（P<0.01），N-cadherin、vimentin 蛋白表达显著降低（均P<0.01）。结论：低表达的FBXO2 可抑制胃 癌细胞的增殖、迁移和侵袭能力，该抑制作用可能与EMT过程有关。

Gene Therapy of Adult Neuronal Ceroid Lipofuscinoses with CRISPR/Cas9 in Zebrafish.

Adult-onset neuronal ceroid lipofuscinosis (ANCL), one of the neuronal ceroid lipofuscinosis (NCLs), is an inherited neurodegenerative disorder with progressive neuronal dysfunction. Recently, mutations in the DNAJC5 gene that encodes cysteine-string protein alpha (CSPα) have been reported to be associated with familial autosomal-dominant ANCL (AD-ANCL). This study constructed an ANCL transgenic zebrafish model expressing the human mutant DNAJC5 (mDNAJC5) gene under the control of a zebrafish neuron-specific promoter. To investigate whether gene therapy based on genome-editing technology could treat ANCL, a panel of TALEN and Cas9 nucleases was designed to disrupt the mDNAJC5 gene in this transgenic animal model. By screening these nucleases, it was found that one nuclease that targeted the 5' coding region efficiently alleviated mDNAJC5 protein aggregates in the affected neurons. Therefore, this study provides a gene therapy strategy via the use of the CRISPR/Cas9 system to treat neural genetic diseases.