Effect of Resistance Exercise on the Lipolysis Pathway in Obese Pre- and Postmenopausal Women.

Physical exercise may stimulate lipolytic activity within adipose tissue. Furthermore, resistance exercise may contribute to the more efficient reduction in adipose tissue mass and prevent the accumulation thereof in obese women. The purpose of this study was to examine the effects of regular resistance exercise for 12 weeks on the lipolysis pathway in women with obesity. Twenty-three pre- and postmenopausal women with body fat percentages of 30% or more were divided into the premenopausal group (n = 9) and the postmenopausal group (n = 14). All subjects participated in resistance exercise training for 12 weeks. Anthropometric and physical fitness tests were performed on all participants. Protein analyses were performed on extracted subcutaneous fatty tissue, and changes in the relevant protein levels in the samples were analyzed by Western blotting. All serum samples were submitted for enzyme-linked immunosorbent assay measurements of adipocyte factors. After 12 weeks, the adipose triglyceride lipase, monoacylglycerol lipase, and perilipin1 protein levels were significantly lower in the postmenopausal group than in the premenopausal group. The hormone-sensitive lipase protein levels were significantly higher in the postmenopausal group than in the premenopausal group. In addition, leptin concentrations were significantly decreased after resistance exercise in the postmenopausal group. Adiponectin concentrations were significantly increased after resistance exercise in both groups. These findings indicate that regular resistance exercise is effective in reducing the weight and body fat of obese premenopausal women, and in the secretion of adiponectin. On the other hand, postmenopausal women were found to have redeced weight and body fat, and were found to be positive for the secretion of adipokine factors. In addition, positive changes in lipolysis pathway factors in adipose tissue promote lipid degradation and reduce fat mass. Thus, regular resistance exercise shows positive changes in the lipolysis pathway more effectively in weight and body fat reduction in postmenopausal women than in premenopausal women.

Calcium Silicate-Based Biocompatible Light-Curable Dental Material for Dental Pulpal Complex.

Dental caries causes tooth defects and clinical treatment is essential. To prevent further damage and protect healthy teeth, appropriate dental material is a need. However, the biocompatibility of dental material is needed to secure the oral environment. For this purpose, biocompatible materials were investigated for incorporated with dental capping material. Among them, nanomaterials are applied to dental materials to enhance their chemical, mechanical, and biological properties. This research aimed to study the physicochemical and mechanical properties and biocompatibility of a recently introduced light-curable mineral trioxide aggregate (MTA)-like material without bisphenol A-glycidyl methacrylate (Bis-GMA). To overcome the compromised mechanical properties in the absence of Bis-GMA, silica nanoparticles were synthesized and blended with a dental polymer for the formation of a nano-network. This material was compared with a conventional light-curable MTA-like material that contains Bis-GMA. Investigation of the physiochemical properties followed ISO 4049. Hydroxyl and calcium ion release from the materials was measured over 21 days. The Vickers hardness test and three-point flexural strength test were used to assess the mechanical properties. Specimens were immersed in solutions that mimicked human body plasma for seven days, and surface characteristics were analyzed. Biological properties were assessed by cytotoxicity and biomineralization tests. There was no significant difference between the tested materials with respect to overall physicochemical properties and released calcium ions. The newly produced material released more calcium ions on the third day, but 14 days later, the other material containing Bis-GMA released higher levels of calcium ions. The microhardness was reduced in a low pH environment, and differences between the specimens were observed. The flexural strength of the newly developed material was significantly higher, and different surface morphologies were detected. The recently produced extract showed higher cell viability at an extract concentration of 100%, while mineralization was clear at the conventional concentration of 25%. No significant changes in the physical properties between Bis-GMA incorporate material and nanoparticle incorporate materials.

Effects of resistance exercise on adipokine factors and body composition in pre- and postmenopausal women.

The objective of the present study was to examine effects of resistance exercise for 12 weeks on adipokine factors and body composition in postmenopausal (POM) women to provide basic data for preventing obesity or metabolic syndrome caused by menopause. Subjects of this study were 35 premenopausal (PRM) and POM women with body fat percentages of 30% or more. They were divided into PRM (n=15) and POM (n=20) groups. All subjects participated in resistance exercise training for 12 weeks. All serum samples were submitted for enzyme-linked immunosorbent assay measurements of adipokine factors. Body weight, muscle mass, body mass index, and waist-to-hip ration showed significant differences between the two groups after training. In contrast, body fat percentage did not differ between the groups, although it was significantly lower in the PRM group after exercise. Physical fitness was significant differences between the two groups after training, including grip strength (left and right), sit and reach, sit-ups, and standing long jump. In addition, grip strength (left), sit-up, and side step tests were significantly increased after exercise in the PRM group. There were the significant differences in interleukin-6 and leptin levels between the two groups after training. Interleukin-6, interleukin-15, and adiponectin levels were significantly higher in both groups after training compared to those before training, although leptin levels were significantly lower after exercise in the PRM group. Regular resistance exercise was found to be effective in decreasing body fat in PRM women, and decreased leptin and increased adiponectin were positively significant in both groups.

Moisture condensation behavior of hierarchically carbon nanotube-grafted carbon nanofibers.

Hierarchical micro/nanosurfaces with nanoscale roughness on microscale uneven substrates have been the subject of much recent research interest because of phenomena such as superhydrophobicity. However, an understanding of the effect of the difference in the scale of the hierarchical entities, i.e., nanoscale roughness on microscale uneven substrates as opposed to nanoscale roughness on (a larger) nanoscale uneven surface, is still lacking. In this study, we investigated the effect of the difference in scale between the nano- and microscale features. We fabricated carbon nanotube-grafted carbon nanofibers (CNFs) by dispersing a catalyst precursor in poly (acrylonitrile) (PAN) solution, electrospinning the PAN/catalyst precursor solution, carbonization of electrospun PAN nanofibers, and direct growth of carbon nanotubes (CNTs) on the CNFs. We investigated the relationships between the catalyst concentrations, the size of catalyst nanoparticles on CNFs, and the sizes of CNFs and CNTs. Interestingly, the hydrophobic behavior of micro/nano and nano/nano hierarchical surfaces with water droplets was similar; however a significant difference in the water condensation behavior was observed. Water condensed into smaller droplets on the nano/nano hierarchical surface, causing it to dry much faster.

Facile conductive bridges formed between silicon nanoparticles inside hollow carbon nanofibers.

This paper reports on a simple and effective method for improving the electrochemical performance of silicon nanoparticle-core/carbon-shell (Si-core/C-shell) nanofibers. Instead of increasing the encapsulation amount of Si nanoparticles, additional conductive paths between the Si nanoparticles were formed by incorporating a small percentage of multi-walled carbon nanotubes (MWNTs) (e.g., 5 wt% with respect to Si) into the Si nanoparticle core. The electrical conductivity of a single Si-core/C-shell nanofiber was measured by a four-point probe using four nano-manipulators, which showed a more than five times increase according to MWNT addition. A galvanostatic charge-discharge test demonstrated that a small amount of MWNTs greatly improved the electrochemical performance of the Si-core/C-shell nanofibers (e.g., a 25.1% increase in the Li-ion storage capability) due to the enhanced participation of Si through the additional conductive paths formed between the Si nanoparticles.

Effect of pores in hollow carbon nanofibers on their negative electrode properties for a lithium rechargeable battery.

The effect of pores in hollow carbon nanofibers (HCNFs) on their electrochemical performance is investigated because the carbon shell itself acts as a reservoir for accommodating Li-ions through intercalation and simultaneously becomes a transport medium through which Li-ions migrate into the core materials in HCNFs. Porous HCNFs (pHCNFs) are prepared by the coaxial electrospinning of a sacrificial core solution and an emulsified shell solution containing sacrificial islands for pore generation. After a thermal treatment, a systematic study is carried out to relate the resulting pore size in pHCNFs to the sacrificial islands in the emulsified shell. As the pores are introduced in pHCNFs, their initial capacity and reversible capacity rate are proved to increase significantly to 1003 mAhg(-1) and 61.8%, respectively, compared to those (653 mAhg(-1) and 53.9%) of nonporous HCNFs. The increased pore size and expanded graphene layers are believed to facilitate lithium insertion/extraction behavior.