An Antisense Oligonucleotide against a Splicing Enhancer Sequence within Exon 1 of the MSTN Gene Inhibits Pre-mRNA Maturation to Act as a Novel Myostatin Inhibitor

Antisense oligonucleotides (ASOs) are agents that modulate gene function. ASO-mediated out-of-frame exon skipping has been employed to suppress gene function. Myostatin, encoded by the MSTN gene, is a potent negative regulator of skeletal muscle growth. ASOs that induce skipping of out-of-frame exon 2 of the MSTN gene have been studied for their use in increasing muscle mass. However, no ASOs are currently available for clinical use. We hypothesized that ASOs against the splicing enhancer sequence within exon 1 of the MSTN gene would inhibit maturation of pre-mRNA, thereby suppressing gene function. To explore this hypothesis, ASOs against sequences of exon 1 of the MSTN gene were screened for their ability to reduce mature MSTN mRNA levels. One screened ASO, named KMM001, decreased MSTN mRNA levels in a dose-dependent manner and reciprocally increased MSTN pre-mRNA levels. Accordingly, KMM001 decreased myostatin protein levels. KMM001 inhibited SMAD-mediated myostatin signaling in rhabdomyosarcoma cells. Remarkably, it did not decrease GDF11 mRNA levels, indicating myostatin-specific inhibition. As expected, KMM001 enhanced the proliferation of human myoblasts. We conclude that KMM001 is a novel myostatin inhibitor that inhibits pre-mRNA maturation. KMM001 has great promise for clinical applications and should be examined for its ability to treat various muscle-wasting conditions.     

Modification and development of the optical,structural, thermal and electrical characterization of Chitosan incorporated with Au/Bi2O3/Mo NPs fabricated by laser ablation

The molecular structures of pure polymer (chitosan) incorporated with ternary metal nanoparticles (Au/Bi₂O₃/Mo) synthesized by laser ablation have been performed ia FT-IR and XRD. The surface of the synthesized samples has been investigated ia SEM. Thermal, electrical, and dielectric haracterization have been performed to utilized in energy applications. XRD patterns display the amorphous nature of chitosan (Cs), characterized by two hump peaks at 2? =11.34^o and 2? =19.57^o, which disappeared by doped with Au/Bi₂O₃/Mo NPs. FT-IR spectra revealed that thereare complexation between Cs and Au/Bi₂O₃/Mo NPs took place in amorphous regions. SEM displays grains with rectangular shape after adding different filling nanoparticles, and rod-shaped formed on the surface of the samples.TGA curves obtained the enhancement in the thermal stability of samples . The AC conductivity of the samples increased by the addition of Au/Bi₂O₃/Mo NPs. The results confirm that nanocomposite of Cs/metal have excellent thermal and electronic haracterization, which may suggest the utilization of these nanocomposites in energy storage.

     

仿生设计在汽车造型设计中应用的内容分析

以汽车造型设计中的形态仿生设计为启示,分析了汽车造型设计中的美学规律和汽车造型设计中的色彩仿生设计,论述了汽车造型设计中的功能仿生设计特点和汽车造型设计中的结构仿生设计特点,提出了仿生设计的基本方法,并通过具体案例,分析我国汽车造型设计领域里导入仿生设计这一设计手段的可行性和意义。     

Isolation and Enhancement of a Homogenous in Vitro Human Hertwig’s Epithelial Root Sheath Cell Population

Hertwig’s epithelial root sheath (HERS) cells play a pivotal role during root formation of the tooth and are able to form cementum-like tissue. The aim of the present study was to establish a HERS cell line for molecular and biochemical studies using a selective digestion method. Selective digestion was performed by the application of trypsin-EDTA for 2 min, which led to the detachment of fibroblast-like-cells, with the rounded cells attached to the culture plate. The HERS cells displayed a typical cuboidal/squamous-shaped appearance. Characterization of the HERS cells using immunofluorescence staining and flow cytometry analysis showed that these cells expressed pan-cytokeratin, E-cadherin, and p63 as epithelial markers. Moreover, RT-PCR confirmed that these cells expressed epithelial-related genes, such as cytokeratin 14, E-cadherin, and ΔNp63. Additionally, HERS cells showed low expression of CD44 and CD105 with absence of CD34 and amelogenin expressions. In conclusion, HERS cells have been successfully isolated using a selective digestion method, thus enabling future studies on the roles of these cells in the formation of cementum-like tissue in vitro.