Ni-dispersed fullerenes: Hydrogen storage and desorption properties

Our study shows that the H2 storage media using Ni-dispersed fullerenes could be viable alternatives to reversible hydrogen storage. It is demonstrated that a single Ni coated on the fullerene surface can store up to three H2 molecules. Consequently, at high Ni coverage, Ni-dispersed fullerenes are considered to be the novel hydrogen storage media capable of storing ~6.8 wt % H2, thus exceeding the Department of Energy target (6.5 wt %) for automobile applications. Moreover, the H2 desorption activation barrier of 11.8 kcal/mol H2 is ideal for many practical hydrogen storage applications

Thermoelectric properties of graphene incorporated thermoelectric materials

Thermoelectric materials, which can change the waste heat into the usable electricity, are interested in various field of applications such as vehicle, ship, power plane, and so on. To enhance the thermoelectric properties, high electrical conductivity, high Seebeck coefficient, and low thermal conductivity should be conducted, however, the trade-off relation between electronic property and thermal property in terms of carrier concentration could be the bottle-neck on the enhancement of thermoelectric properties of the materials. In this presentation, we discuss with the graphene incorporation in the conventional thermoelectric materials, which could lead to independently control electric and thermal properties

A carbon nanotubes-silicon nanoparticles network for high performance lithium rechargeable battery anodes

As an effort to address the chronic capacity fading of Si anodes and thus achieve their robust cycling performance, herein, we develop a unique electrode in which silicon nanoparticles are embedded in the carbon nanotubes network. Utilizing robust contacts between silicon nanoparticles and carbon nanotubes, the composite electrodes exhibit excellent electrochemical performance : 95.5% capacity retention after 140 cycles as well as rate capability such that at the C-rate increase from 0.1C to 1C to 10C, the specific capacities of 850, 698, and 312 mAh/g are obtained, respectively. The present investigation suggests a useful design principle for silicon as well as other high capacity alloying electrodes that undergo large volume expansions during battery operations.

Cyclic ADP Ribose-Dependent Ca2+ Release by Group I Metabotropic Glutamate Receptors in Acutely Dissociated Rat Hippocampal Neurons

Group I metabotropic glutamate receptors (group I mGluRs; mGluR1 and mGluR5) exert diverse effects on neuronal and synaptic functions, many of which are regulated by intracellular Ca2+. In this study, we characterized the cellular mechanisms underlying Ca2+ mobilization induced by (RS)-3,5-dihydroxyphenylglycine (DHPG; a specific group I mGluR agonist) in the somata of acutely dissociated rat hippocampal neurons using microfluorometry. We found that DHPG activates mGluR5 to mobilize intracellular Ca2+ from ryanodine-sensitive stores via cyclic adenosine diphosphate ribose (cADPR), while the PLC/IP3 signaling pathway was not involved in Ca2+ mobilization. The application of glutamate, which depolarized the membrane potential by 28.5±4.9 mV (n = 4), led to transient Ca2+ mobilization by mGluR5 and Ca2+ influx through L-type Ca2+ channels. We found no evidence that mGluR5-mediated Ca2+ release and Ca2+ influx through L-type Ca2+ channels interact to generate supralinear Ca2+ transients. Our study provides novel insights into the mechanisms of intracellular Ca2+ mobilization by mGluR5 in the somata of hippocampal neurons

Preparation and evaluation of polymeric microparticulates for improving cellular uptake of gemcitabine

Ji-Ho Lim1,*, Sung-Kyun You1,*, Jong-Suep Baek1, Chan-Ju Hwang1, Young-Guk Na1, Sang-Chul Shin2, Cheong-Weon Cho11College of Pharmacy and Institute of Drug Research and Development, Chungnam National University, Gungdong, Yuseonggu, Daejeon, South Korea, 2College of Pharmacy, Chonnam National University, Buggu, Gwangju, South Korea *These authors contributed equally to this workBackground: Gemcitabine must be administered at high doses to elicit the required therapeutic response because of its very short plasma half-life due to rapid metabolism. These high doses can have severe adverse effects.Methods: In this study, polymeric microparticulate systems of gemcitabine were prepared using chitosan as a mucoadhesive polymer and Eudragit L100-55 as an enteric copolymer. The physicochemical and biopharmaceutical properties of the resulting systems were then evaluated.Results: There was no endothermic peak for gemcitabine in any of the polymeric gemcitabine microparticulate systems, suggesting that gemcitabine was bound to chitosan and Eudragit L100-55 and its crystallinity was changed into an amorphous form. The polymeric gemcitabine microparticulate system showed more than 80% release of gemcitabine in 30 minutes in simulated intestinal fluid. When mucin particles were incubated with gemcitabine polymeric microparticulates, the zeta potential of the mucin particles was increased to 1.57 mV, indicating that the polymeric gemcitabine microparticulates were attached to the mucin particles. Furthermore, the F53 polymeric gemcitabine microparticulates having 150 mg of chitosan showed a 3.8-fold increased uptake of gemcitabine into Caco-2 cells over 72 hours compared with gemcitabine solution alone.Conclusion: Overall, these results suggest that polymeric gemcitabine microparticulate systems could be used as carriers to help oral absorption of gemcitabine.Keywords: gemcitabine, polymeric microparticulates, mucoadhesive, enteric coating, cellular uptake, oral absorptio

Silicon@porous nitrogen-doped carbon spheres through a bottom-up approach are highly robust lithium-ion battery anodes

Due to its excellent capacity, around 4000 mA h g(-1), silicon has been recognized as one of the most promising lithium-ion battery anodes, especially for future large-scale applications including electrical vehicles and utility power grids. Nevertheless, Si suffers from a short cycle life as well as limitations for scalable electrode fabrication. Herein, we report a novel design for highly robust and scalable Si anodes: Si nanoparticles embedded in porous nitrogen-doped carbon spheres (NCSs). The porous nature of NCSs buffers the volume changes of Si nanoparticles and thus resolves critical issues of Si anode operations, such as pulverization, vulnerable contacts between Si and carbon conductors, and an unstable solid-electrolyte interphase. The unique electrode structure exhibits outstanding performance with a gravimetric capacity as high as 1579 mA h g(-1) at a C/10 rate based on the mass of both Si and C, a cycle life of 300 cycles with 94% capacity retention, as well as a discharge rate capability of 6 min while retaining a capacity of 702 mA h g(-1). Significantly, the coulombic efficiencies of this structure reach 99.99%. The assembled structure suggests a design principle for high capacity alloying electrodes that suffer from volume changes during battery operations.

Exosomes from Human Adipose Tissue-Derived Mesenchymal Stem Cells Promote Epidermal Barrier Repair by Inducing de Novo Synthesis of Ceramides in Atopic Dermatitis.

Atopic dermatitis (AD) is a multifactorial, heterogeneous disease associated with epidermal barrier disruption and intense systemic inflammation. Previously, we showed that exosomes derived from human adipose tissue-derived mesenchymal stem cells (ASC-exosomes) attenuate AD-like symptoms by reducing multiple inflammatory cytokine levels. Here, we investigated ASC-exosomes' effects on skin barrier restoration by analyzing protein and lipid contents. We found that subcutaneous injection of ASC-exosomes in an oxazolone-induced dermatitis model remarkably reduced trans-epidermal water loss, while enhancing stratum corneum (SC) hydration and markedly decreasing the levels of inflammatory cytokines such as IL-4, IL-5, IL-13, TNF-α, IFN-γ, IL-17, and TSLP, all in a dose-dependent manner. Interestingly, ASC-exosomes induced the production of ceramides and dihydroceramides. Electron microscopic analysis revealed enhanced epidermal lamellar bodies and formation of lamellar layer at the interface of the SC and stratum granulosum with ASC-exosomes treatment. Deep RNA sequencing analysis of skin lesions demonstrated that ASC-exosomes restores the expression of genes involved in skin barrier, lipid metabolism, cell cycle, and inflammatory response in the diseased area. Collectively, our results suggest that ASC-exosomes effectively restore epidermal barrier functions in AD by facilitating the de novo synthesis of ceramides, resulting in a promising cell-free therapeutic option for treating AD

Vaccination with a Human Papillomavirus (HPV)-16/18 AS04-Adjuvanted Cervical Cancer Vaccine in Korean Girls Aged 10-14 Years

The human papillomavirus (HPV)-16/18 AS04-adjuvanted cervical cancer vaccine has been demonstrated to be highly efficacious and immunogenic with a favorable safety profile. This study assessed the immunogenicity and safety of the HPV-16/18 AS04-adjuvanted vaccine in healthy Korean girls aged 10-14 yr. This multi-center, observer-blind trial randomly assigned 321 healthy girls to receive three doses (0, 1, 6-month schedule) of HPV-16/18 AS04-adjuvanted vaccine or hepatitis A vaccine. Immunogenicity against vaccine antigens was assessed one month post-Dose 3. Solicited and unsolicited adverse events (AEs) and serious AEs (SAEs) were recorded. In the according-to-protocol analysis, all initially seronegative subjects vaccinated with the HPV-16/18 AS04-adjuvanted vaccine had seroconverted at Month 7, with a peak geometric mean titer (GMT) that was 600-fold higher than the natural infection titer of 29.8 EU/mL for HPV-16 and a peak GMT that was 400-fold higher than the natural infection titer of 22.6 EU/mL for HPV-18. The vaccine was well tolerated with no increase in reactogenicity with subsequent doses and no reports of vaccine-related SAEs. In conclusion, the HPV-16/18 AS04-adjuvanted vaccine is shown to be highly immunogenic and generally well-tolerated in Korean girls aged 10-14 yr