Effects of Resistance Exercise and Essential Amino Acid Intake on Muscle Quality, Myokine, and Inflammation Factors in Young Adult Males.

BACKGROUND: Recently, many studies have been devoted to discovering nutrients for exercise-like effects. Resistance exercise and the intake of essential amino acids (EAAs) are known to be factors that can affect muscle mass and strength improvement. The purpose of this study was to investigate changes in muscle quality, myokines, and inflammation in response to resistance exercise and EAA supplementation. METHODS: Thirty-four males volunteered to participate in this study. They were assigned to four groups: (1) placebo (CO), (2) resistance exercise (RE), (3) EAA supplementation, and (4) RE + EAA supplementation. Body composition, muscle quality, myokines, and inflammation were measured at baseline and four weeks after treatment. RESULTS: Lean body fat had decreased in both RE and RE + EAA groups. Lean body mass had increased in only the RE + EAA group. In all groups except for CO, irisin, myostatin A, and TNF-α levels had decreased. The grip strength of the right hand and trunk flexion peak torque increased in the RE group. The grip strength of the left hand, trunk flexion peak torque, and knee flexion peak torque of the left leg were increased in RE + EAA. CONCLUSIONS: RE, EAA, and RE + EAA could effectively improve the muscle quality, myokine, and inflammation factors of young adult males. This finding highlights the importance of resistance exercise and amino acid intake.

Reinforcing Synaptic Plasticity of Defect-Tolerant States in Alloyed 2D Artificial Transistors.

While two-dimensional (2D) materials possess the desirable future of neuromorphic computing platforms, unstable charging and de-trapping processes, which are inherited from uncontrollable states, such as the interface trap between nanocrystals and dielectric layers, can deteriorate the synaptic plasticity in field-effect transistors. Here, we report a facile and effective strategy to promote artificial synaptic devices by providing physical doping in 2D transition-metal dichalcogenide nanomaterials. Our experiments demonstrate that the introduction of niobium (Nb) into 2D WSe2 nanomaterials produces charge trap levels in the band gap and retards the decay of the trapped charges, thereby accelerating the artificial synaptic plasticity by encouraging improved short-/long-term plasticity, increased multilevel states, lower power consumption, and better symmetry and asymmetry ratios. Density functional theory calculations also proved that the addition of Nb to 2D WSe2 generates defect tolerance levels, thereby governing the charging and de-trapping mechanisms of the synaptic devices. Physically doped electronic synapses are expected to be a promising strategy for the development of bioinspired artificial electronic devices.

The role of EZH1 and EZH2 in development and cancer.

Polycomb Repressive Complex 2 (PRC2) exhibits key roles in mammalian development through its temporospatial repression of gene expression. EZH1 or EZH2 is the catalytic subunit of PRC2 that mediates the mono-, di- and tri-methylation of histone H3 lysine 27 (H3K27me1/2/3), H3K27me2/me3 being a hallmark of facultative heterochromatin. PRC2 is a chromatinmodifying enzyme that is recruited to a limited number of "nucleation sites", spreads H3K27 methylation and fosters chromatin compaction. EZH1 and EZH2 exhibit differences in their expression patterns, levels of histone methyltransferase activity (HMT) in the context of PRC2, and DNA/nucleosome binding activity. This suggests that their roles in heterochromatin formation are disparate. Dysregulation of PRC2 activity leads to aberrant gene expression and is implicated in cancer and developmental diseases. In this review, we discuss the distinct function of PRC2/EZH1 and PRC2/EZH2 in the early and late developmental stages. We then discuss the cancers associated with PRC2/EZH1 and PRC2/EZH2. [BMB Reports 2022; 55(12): 595-601].

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.

Validation of the Traumatic Antecedents Questionnaire using item response theory.

BACKGROUND: Traumatic Antecedents Questionnaire (TAQ) is a traumatic experience scale that measures exposure to traumatic events across four age periods. Although the TAQ has good convergent validity with other traumatic scales, the classification of the domains and the psychometric properties of the scale has not been verified. METHODS: A total of 290 young adults completed the TAQ, and 156 participated in the retest. The number of trauma domains was determined using principal component analysis. Rasch model was used for verifying the items that each domain might represent in one common measurement. RESULTS: When scores were transformed as binary a code 0 and 1 from the original 4 categories, 8 domains were established consisting of Domestic violence, Sexual/other rare trauma, Incompetence, Caring family, Accidents to close person, Unstable caring environment, Safe environment, and Lack of sexual/extreme trauma. Most domains had acceptable psychometric properties with a mean-square fit value within the range of 0.7-1.3. The Bland and Altman analysis suggest 98.7% of difference scores between test and retest were within ±2 standard deviations from the mean. TAQ severity showed a significant relationship with the multiplicity score of the Maltreatment and Abuse Chronology of Exposure scale (r = 0.677). CONCLUSIONS: The newly proposed scoring system and 8 domains for the TAQ demonstrated excellent internal consistency, test-retest reliability, and validity. Further studies are needed to develop new items in domains with less than 5 items to improve the psychometric properties of the scale and to create a maltreatment domain that includes bullying items.

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.