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One of the key challenges in the experimental and therapeutic use of gene delivery agents is the development of methods that can efficiently deliver nucleic acids into living systems. During the past decade, the development of effective and safe gene delivery systems has been intensively investigated. This review summarizes the current state of gene delivery methods based on viral and non-viral agents. [ABSTRACT FROM AUTHOR]

In this study, we determined the effect of TNF-α on hBMSCs proliferation as well as the role of IL-1 receptor-associated kinase 1 (IRAK1) on TNF-α signaling. Western blot analysis revealed that TNF-α treatment increased the phosphorylation of IRAK1 in hBMSCs. The downregulation of IRAK1 inhibited TNF-α-induced NF-κB activation and COX-2 expression. TNF-α treatment increased hBMSCs proliferation in a dose-dependent manner and increased ERK, JNK, and NF-κB activity. U0126, an ERK inhibitor, decreased hBMSCs proliferation and significantly blocked TNF-α -induced hBMSCs proliferation. In cells with IRAK1 or TRADD downregulation, the U0126 treatment inhibited hBMSCs proliferation and significantly suppressed TNF-α-induced hBMSCs proliferation. The downregulation of IRAK1 or TRADD inhibited TNF-α-induced ERK and JNK activation, and hBMSCs proliferation. Inhibition of NF-κB by decoy oligonucleotides reduced the TNF-α-induced hBMSCs proliferation. Immunoprecipitation analysis showed that IRAK1 does not physically interact with TNF receptor 1 (TNFR1) even in the presence of TNF-α. Suppression of IRAK1 binding protein (IRAK1BP1) inhibited TNF-α-induced increase of the proliferation and ERK1 phosphorylation of hBMSCs in the presence of TNF-α. Our data indicate that TNF-α modulates hBMSCs proliferation through ERK signaling pathways, and that IRAK1 plays an important role in TNF-α-induced NF-κB activation in hBMSCs. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Previous studies have shown that functionalized gold nanoparticles (AuNPs) can be used as a general platform for loading and delivering DNA oligonucleotides and short hairpin RNA to living systems. Here, we report the ability of functionalized AuNP to deliver RNA aptamers into the nuclei of human cells. An in vitro-synthesized RNA aptamer specific to the β-catenin protein was delivered into the HepG2 human cell line more efficiently via functionalized AuNP than liposome-based delivery, and resulted in nearly complete inhibition of β-catenin binding to the p50 subunit of NF-κB in the nucleus. This inhibition led to repression of NF-κB p50-dependent transcription of CRP. Also, the β-catenin aptamer in the nucleus led to down-regulation of β-catenin-mediated transcriptional activity through the TCF complex and resulted in decrease in the levels of cyclin D, and c-myc mRNA by ∼47% and ∼57%, respectively. In addition, we used functionalized AuNP to deliver another RNA aptamer targeted to the p50 subunit of NF-κB into the A549 human cell line, and this was sufficient to induce apoptosis of the cells. Our findings demonstrate that AuNP GDS can be used to deliver small, highly structured RNA aptamers into the nucleus of human cells where they modulate the activity of transactivators by interacting with target proteins. [Copyright &y& Elsevier]

Currently, studies of flux switching machines are actively underway owing to several advantages of these machines, including their sturdy rotor structure and high output capability. This paper deals with an outer-rotor hybrid-excited flux-switching machine (FSM). The proposed machine embraces a homopolar structure and utilizes permanent magnets (PMs) for field excitation and a high-temperature superconducting (HTS) coil for flux regulation. The stator houses the HTS field coil, PMs, and armature windings. The outer rotor consists solely of an iron core. Thus, the machines are cost effective and can serve as a solution to the design and fabrication complexities of field current supplying and cooling systems. In this paper, the machine performance outcomes are analyzed using the 3D finite element method (FEM), and the validity of the proposed machine is verified. [ABSTRACT FROM AUTHOR]

Abstract: A prerequisite for the therapeutic use of small RNAs is the development of a method that can deliver them into animals. Previous studies have shown the capability of functionalized gold nanoparticles to serve as a general platform for loading and delivering DNA oligonucleotides and short hairpin RNAs (shRNAs) into cultured human cells. Here, we report the ability of the gold nanoparticle-assisted gene delivery system (AuNP-GDS) to deliver shRNA to a xenograft tumor in a mouse model. AuNP-GDS delivery of in vitro synthesized shRNA targeted to the Mcl-1L gene knocked down levels of Mcl-1L mRNA and protein by ∼36% and ∼26%, respectively, which were sufficient to induce apoptosis of the xenograft tumor cells and consequently inhibited the development of the tumor. We demonstrated that our lego-like AuNP-GDS, which can easily load and deliver shRNAs targeted to any gene of interest into living systems, can deliver shRNAs into xenograft tumors, leading to antitumor activity in an animal model. [Copyright &y& Elsevier]

Abstract: Nano-scale interfacial details of ultrasonic AlSi1 wire wedge bonding to a Au/Ni/Cu pad were investigated using high resolution transmission electron microscopy (HRTEM). The intermetallic phase Au8Al3 formed locally due to diffusion and reaction activated by ultrasound at the Al/Au bond interface. Multilayer sub-interfaces roughly parallel to the wire/pad interface were observed among this phase, and interdiffusional features near the Au pad resembled interference patterns, alternately dark and bright bars. Solid-state diffusion theory cannot be used to explain why such a thick compound formed within milliseconds at room temperature. The major formation of metallurgical bonds was attributed to ultrasonic cyclic vibration. [Copyright &y& Elsevier]

Graphical abstract Highlights • Nitrate depletion, salt, and LED wavelengths of second-phase were used for stresses. • Green LED wavelength stress induced the production of microalgal lipid. • The three microalgae, P. tricornutum have high nitrate uptake for cell growth. • The synthesis of fatty acids in microalgae led to form UFAs by stresses. Abstract The effects of wavelengths of light-emitting diode (LED), nitrate concentration, and salt concentration were evaluated for the two-phase culture of the microalgal species Phaeodactylum tricornutum , Dunaliella tertiolecta , and Isochrysis galbana on cell growth and lipid production. Blue LEDs produced the highest biomass of P. tricornutum at a nitrate concentration of 8 mg/L, reaching 0.97 g dcw/L with a specific growth rate (μ) of 0.047 h−1, followed by I. galbana with 0.79 g dcw/L and μ = 0.040 h−1 and D. tertiolecta with 0.55 g dcw/L and μ = 0.028 h−1. Of the three microalgae, P. tricornutum had the highest specific growth rate of μ max = 0.070 h−1 and lowest saturation constant of K s = 4.18 mg/L, resulting in fast cell growth. The highest lipid production was obtained under green LED wavelength stress on day 14, reaching 60.6% (w/w) of the dry cell weight among the three microalgae. The main fatty acids produced by the three microalgae were myristic acid (C14:0), palmitic acid (C16:0), oleic acid (C18:1), and arachidic acid (C20:0), which comprised 72.68%–84.16% (w/w) of the total fatty acids content under three stresses. [ABSTRACT FROM AUTHOR]

Highlights • N. oceanica was cultured in 14-L photobioreactors using a three-phase culture system. • Maximum biomass was produced with 24 h blue LED light at an intensity of 250 µmol m−2 s−1. • Maximum lipid content was obtained with 24 h green LED light at an intensity of 250 µmol m−2 s−1. • SFAs were changed to MUFAs and PUFAs at low temperatures (15, 10, and 5 °C). • The highest PUFA content was obtained at a culture temperature of 5 °C. Abstract A three-phase culture system combining blue (465 nm) light-emitting diode (LED) wavelength as the first phase, green (550 nm) as the second phase, and temperature stress as the third phase was applied to a Nannochloropsis oceanica culture in 14-L photobioreactors. Microalgal growth promotion parameters were optimized in the first phase, followed by green LED stress for lipid production in the second phase. Maximum biomass and lipid production values of 0.75 gdcw L−1 and 57.6% (w/w) were obtained at an aeration rate of 0.50 vvm, with a light intensity of 250 µmol m−2 s−1 and 24:0 h light/dark cycle. Culture temperatures of 15, 10 and 5 °C were applied in the third phase, where temperature stress induced the production of monounsaturated and polyunsaturated fatty acid synthesis in N. oceanica. The production of α-linolenic acid, eicosapentaenoic acid and docosahexaenoic acid increased by 52% (w/w), 96% (w/w), and 77% (w/w), respectively, at 5 °C in the third phase. [ABSTRACT FROM AUTHOR]

This paper reports the feasibility of the impregnation of no-insulation (NI) high-temperature superconducting (HTS) coils using an electrically conductive epoxy resin. Recently, several studies of HTS coils without turn-to-turn insulation have been reported for field coils used in rotating machines such as motors and generators. The NI winding technique enhances the thermal stability of the HTS coil without requiring complicated protection techniques because the quench current is automatically bypassed through the turn-to-turn contacts within the HTS coil. Nevertheless, there is still a question as to whether the NI technique can be applied to rotating machines. To utilize an HTS coil under high mechanical loads such as field coils for rotating machines, the HTS tapes must be stabilized mechanically. For HTS field coils intended for use in rotating machines, epoxy impregnation is generally necessary to protect the HTS field coil from mechanical disturbances caused by the magnetic field and rotational vibration of the rotor to enhance the mechanical stability [1], [2] . However, the NI HTS coil cannot be fabricated by wet winding using epoxy resin because epoxy resins such as Stycast 2850 FT and CTD 521 are electrically insulating materials. This study examines the electrical stability of an NI HTS coil impregnated with an epoxy resin containing electrically conductive particles. The results are likely to present useful data for the application of electrically conductive epoxy impregnated NI HTS coils to rotating machines. [ABSTRACT FROM PUBLISHER]

Abstract: The passivating layer (also called the solid electrolyte interface, SEI) plays a key role in the performances of Li-ion batteries. In this work, we studied the surface reactions of Li[Ni0.31Co0.32Mn0.28Al0.09]O2 with the organic electrolyte in the overcharge state by means of FTIR, XPS, XAS, and 2D correlation analysis. The FTIR and XPS results revealed that several types of compounds are formed on the cathode surface. These results also suggest that the organic solvents are decomposed to a greater extent than the Li-salt during the overcharge state. Based on the 2D correlation analysis, we can deduce the following sequence of events: 287.0 (due to C−O)→290.0 (due to carbonate)→288.5 (due to C sp="0.25" />→291.5 (due to C−F x )→284.5eV (due to C:glyph name="sbnd" />H). [Copyright &y& Elsevier]