艾灸对衰老模型大鼠线粒体DNA含量的影响

目的:探讨艾灸对衰老模型大鼠肝细胞线粒体DNA含量的影响。方法:将36只SD大鼠随机分为3组:青年对照组、衰老模型组、艾灸治疗组。采用25%D-半乳糖溶液125mg/kg·d-1皮下注射复制衰老大鼠模型,采用紫外分光光度法观察艾灸对衰老模型大鼠肝细胞线粒体DNA含量的影响。结果:与青年对照组比较,衰老模型组大鼠肝细胞线粒体DNA含量明显增加(P<0.05);与衰老模型组比较,艾灸治疗组大鼠肝细胞线粒体DNA含量明显减少(P<0.05)。结论:艾灸可以减少肝细胞线粒体DNA的含量,从而起到延缓衰老的作用。     

Catechin-7-O-α-L-rhamnopyranoside can reduce α-MSH-induced melanogenesis in B16F10 melanoma cells through competitive inhibition of tyrosinase

Although melanogenesis is a defense mechanism against ultraviolet (UV)-induced skin damage, abnormally excessive melanin production causes pigmentation disorders. Tyrosinase, as a key factor for melanin synthesis, plays an important role in inducing skin pigmentation. Therefore, the inhibition of tyrosinase is crucial in preventing skin pigmentation in the cosmetics and medicine fields. However, the majority of well-known tyrosinase inhibitors have been discontinued due to toxic effects on the skin or lack of selectivity and/or stability. In this study, we evaluated possible anti-melanogenic effects of catechin-7-O-α-L-rhamnopyranoside (C7R) isolated from the stem bark of Ulmus parvifolia, to discover a new tyrosinase inhibitor that has both safety and stability. When C7R was pretreated in B16F10 melanoma cells stimulated by α-melanocyte-stimulating hormone, this compound reduced melanin accumulation and murine tyrosinase activity. In line with these results, C7R inhibits tyrosinase purified from a mushroom in vitro like kojic acid and arbutin. Furthermore, C7R exhibited a competitive inhibition on a Lineweaver-Burk plot. Next, the underlying mechanisms of the C7R-mediated tyrosinase inhibitory effect were sought through docking simulation and pharmacophore analysis between tyrosinase residues and C7R. The results of these analyses showed that C7R had binding energy of -14.5kcal/mol, and indicated that C7R interacts with tyrosinase through an aromatic ring and various hydrophobic and hydrogen bonds. Together, our results suggest that C7R can be applied as a novel natural anti-melanogenic agent that inhibits tyrosinase.     

An Evaluation of the Hydrolytic Stability of Selected Experimental Dental Matrices and Composites

Materials with potential use as dental restoration should be evaluated in an aggressive environment. Such accelerated aging is widely used in other industries and allows the assessment of service life. In the presented study, three neat resins (UDMA/Bis-GMA/TEGDMA 70/10/20 wt.%, UDMA/Bis-GMA/TEGDMA 40/40/20 wt.% and UDMA/Bis-EMA/TEGDMA 40/40/20 wt.%) and three composites based on these matrices were tested before and after aging protocols (I-7500 cycles, 5 °C and 55 °C, water and 7 days, 60 °C, 0.1 M NaOH; II-5 days, 55 °C, water and 7 days, 60 °C, 0.1 M NaOH). Flexural strength (FS), diametral tensile strength (DTS) and hardness (HV) were determined. Applied aging protocols resulted in a decrease in the value of the FS, DTS and HV. Larger changes were noticed for the neat resins. Materials in which the content of bis-GMA was lower or substituted by bis-EMA showed better resistance to degradation. The choice of mixtures with monomers characterized by lower sorption values may favorably affect hydrolytic stability. It was shown that for composites there was a drastic decrease in hardness, which suggests a more superficial effect of the used protocols. However, degradation of the surface layer can result in a growing problem over time given that the mastication processes are an inherent element in the oral environment.     

Changes in Facial Morphology Using Poly-L-lactic Acid Application According to Vector Technique: A Case Series

BackgroundThe search for nonsurgical cosmetic procedures has increased considerably in recent years. A new injection technique, using vector direction, has shown good results in improving facial aesthetics but to date has only been performed with hyaluronic acid which can be associated with a risk of vascular complications. Therefore, in clinical practice, it would be interesting to assess this technique with a liquid product already widely used in the facial region, and at the same time bring the same aesthetic benefits, but with greater durability than hyaluronic acid.ObjectiveTo investigate the improvement of facial morphology in patients with facial flaccidity submitted to the vector technique using poly-L-lactic acid (PLLA) (Sculptra^®; Galderma, Lausanne, Switzerland).Case SeriesHere we report the outcomes of three cases of female patients, aged between 41 and 55 years, seeking improvement of facial flaccidity. In each patient, PLLA was applied in the posterior temporal region as a bolus, in three points, with a 2-mL injection in the upper region, 1.5mL in the midpoint, and 1.5mL at the bottom point. Each of the three patients showed an improvement in face morphology, with concomitant improvement in the support and stretching of the face and improvement in skin sagging in the upper, middle, and bottom regions.ConclusionThe vector technique with PLLA is a viable alternative for the treatment of patients with facial skin flaccidity, providing harmonious and progressive improvement in the face morphology.     

Establishing a baseline phase behavior in magnetic resonance imaging to determine normal vs. abnormal iron content in the brain

PURPOSE: To establish a baseline of phase differences between tissues in a number of regions of the human brain as a means of detecting iron abnormalities using magnetic resonance imaging (MRI). MATERIALS AND METHODS: A fully flow-compensated, three-dimensional (3D), high-resolution, gradient-echo (GRE) susceptibility-weighted imaging (SWI) sequence was used to collect magnitude and phase data at 1.5 T. The phase images were high-pass-filtered and processed region by region with hand-drawn areas. The regions evaluated included the motor cortex (MC), putamen (PUT), globus pallidus (GP), caudate nucleus (CN), substantia nigra (SN), and red nucleus (RN). A total of 75 subjects, ranging in age from 55 to 89 years, were analyzed. RESULTS: The phase was found to have a Gaussian-like distribution with a standard deviation (SD) of 0.046 radians on a pixel-by-pixel basis. Most regions of interest (ROIs) contained at least 100 pixels, giving a standard error of the mean (SEM) of 0.0046 radians or less. In the MC, phase differences were found to be roughly 0.273 radians between CSF and gray matter (GM), and 0.083 radians between CSF and white matter (WM). The difference between CSF and the GP was 0.201 radians, and between CSF and the CN (head) it was 0.213 radians. For CSF and the PUT (the lower outer part) the difference was 0.449 radians, and between CSF and the RN (third slice vascularized region) it was 0.353 radians. Finally, the phase difference between CSF and SN was 0.345 radians. CONCLUSION: The Gaussian-like distributions in phase make it possible to predict deviations from normal phase behavior for tissues in the brain. Using phase as an iron marker may be useful for studying absorption of iron in diseases such as Parkinson's, Huntington's, neurodegeneration with brain iron accumulation (NBIA), Alzheimer's, and multiple sclerosis (MS), and other iron-related diseases. The phases quoted here will serve as a baseline for future studies that look for changes in iron content.     

Alterations in Bacterial Metabolism Contribute to the Lifespan Extension Exerted by Guarana in Caenorhabditis elegans

Guarana (Paullinia cupana) is a widely consumed nutraceutical with various health benefits supported by scientific evidence. However, its indirect health impacts through the gut microbiota have not been studied. Caenorhabditis elegans is a useful model to study both the direct and indirect effects of nutraceuticals, as the intimate association of the worm with the metabolites produced by Escherichia coli is a prototypic simplified model of our gut microbiota. We prepared an ethanoic extract of guarana seeds and assessed its antioxidant capacity in vitro, with a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, and in vivo, utilizing C. elegans. Additionally, we studied the impact of this extract on C. elegans lifespan, utilizing both viable and non-viable E. coli, and assessed the impact of guarana on E. coli folate production. The extract showed high antioxidant capacity, and it extended worm lifespan. However, the antioxidant and life-extending effects did not correlate in terms of the extract concentration. The extract-induced life extension was also less significant when utilizing dead E. coli, which may indicate that the effects of guarana on the worms work partly through modifications on E. coli metabolism. Following this observation, guarana was found to decrease E. coli folate production, revealing one possible route for its beneficial effects.     

Consumption of Vegetables Is Associated with Systemic Inflammation in Older Adults

It is hypothesized that healthy diets rich in fruits and vegetables (FV) can modulate the inflammatory status in older adults. However, to determine the actual impact of FV on inflammatory status, adiposity level and objectively assessed physical activity (PA) behaviors need to be considered. The aim of the present study was to explore associations between FV intake and biomarkers of systemic inflammation in older adults. Based on a sample of 233 older adults (65–70 years old), the following inflammatory biomarkers were assessed: C-reactive protein (CRP), fibrinogen, interleukin-6 (IL-6), IL-10, IL-18, and monocyte chemoattractant protein-1 (MCP-1). FV intake was assessed by self-report, and PA behaviors encompassing time spent sedentary and in moderate-to-vigorous PA (MVPA) were determined using accelerometers. Associations between FV intake and inflammatory biomarkers were analyzed using stepwise linear regression models while adjusting for several covariates, including health-related food groups, adherence to the MVPA guidelines, total sedentary time, and waist circumference. While no significant associations were observed for the total FV intake, the vegetable intake was inversely associated with levels of IL6 (β = −0.15; p < 0.05). In contrast, fruit intake was not associated with any inflammatory biomarker. In conclusion, our findings indicate beneficial associations between vegetable intake and levels of a pro-inflammatory biomarker in older adults, which strengthens public health efforts to promote vegetable-rich diets in older adults to mitigate age-related systemic inflammation.     

On Growth and Morphology of TiO2 Nanotubes on CP-Ti by Anodic Oxidation in Ethylene Glycol Electrolyte: Influence of Electrolyte Aging and Anodization Parameters

Anodic oxidation of CP-Ti, for production of TiO₂ nanotubes, has been extensively described in terms of the electrochemical mechanism of tubular growth or the effect of the parameters on the final tube morphology. Recently, a kinetic growth model was proposed to describe the distinct morphologies of the anodic oxide layer as phases of the nanotubular development process, offering a new perspective for the tuning of nanotube production. In this work, the anodizing behavior of a CP-Ti alloy in an ethylene glycol electrolyte was investigated in light of this new model. The final morphology of the nanotubes was characterized by SEM, considering the effects of electrolyte aging, the microstructure, the applied potential difference and time on the morphological development of nanotubes. Electrolyte aging was shown to lead to a decreased dissolution effect on the oxide. The applied potential difference was shown to lead to an increased dissolution effect and more rapid nanotube growth kinetics, while time resulted in extended dissolution. Moreover, the obtained results were analyzed considering a previous study focused on the anodizing behavior of the α- and β-phases of Ti6Al4V alloy. Overall, the tube morphology resembled that obtained for the Al-containing α-phase of the Ti6Al4V alloy, but the growth kinetics were considerably slower on CP-Ti.     

Material Extrusion of Structural Polymer–Aluminum Joints—Examining Shear Strength,Wetting, Polymer Melt Rheology and Aging

Generating polymer–metal structures by means of additive manufacturing offers huge potential for customized, sustainable and lightweight solutions. However, challenges exist, primarily with regard to reliability and reproducibility of the additively generated joints. In this study, the polymers ABS, PETG and PLA, which are common in material extrusion, were joined to grit-blasted aluminum substrates. Temperature dependence of polymer melt rheology, wetting and tensile single-lap-shear strength were examined in order to obtain appropriate thermal processing conditions. Joints with high adhesive strength in the fresh state were aged for up to 100 days in two different moderate environments. For the given conditions, PETG was most suitable for generating structural joints. Contrary to PETG, ABS–aluminum joints in the fresh state as well as PLA–aluminum joints in the aged state did not meet the demands of a structural joint. For the considered polymers and processing conditions, this study implies that the suitability of a polymer and a thermal processing condition to form a polymer–aluminum joint by material extrusion can be evaluated based on the polymer’s rheological properties. Moreover, wetting experiments improved estimation of the resulting tensile single-lap-shear strength.     

Walnut Oil Reduces Aβ Levels and Increases Neurite Length in a Cellular Model of Early Alzheimer Disease

(1) Background: Mitochondria are the cells’ main source of energy. Mitochondrial dysfunction represents a key hallmark of aging and is linked to the development of Alzheimer’s disease (AD). Maintaining mitochondrial function might contribute to healthy aging and the prevention of AD. The Mediterranean diet, including walnuts, seems to prevent age-related neurodegeneration. Walnuts are a rich source of α-linolenic acid (ALA), an essential n3-fatty acid and the precursor for n3-long-chain polyunsaturated fatty acids (n3-PUFA), which might potentially improve mitochondrial function. (2) Methods: We tested whether a lipophilic walnut extract (WE) affects mitochondrial function and other parameters in human SH-SY5Y cells transfected with the neuronal amyloid precursor protein (APP695). Walnut lipids were extracted using a Soxhlet Extraction System and analyzed using GC/MS and HPLC/FD. Adenosine triphosphate (ATP) concentrations were quantified under basal conditions in cell culture, as well as after rotenone-induced stress. Neurite outgrowth was investigated, as well as membrane integrity, cellular reactive oxygen species, cellular peroxidase activity, and citrate synthase activity. Beta-amyloid (Aβ) was quantified using homogenous time-resolved fluorescence. (3) Results: The main constituents of WE are linoleic acid, oleic acid, α-linolenic acid, and γ- and δ-tocopherol. Basal ATP levels following rotenone treatment, as well as citrate synthase activity, were increased after WE treatment. WE significantly increased cellular reactive oxygen species but lowered peroxidase activity. Membrane integrity was not affected. Furthermore, WE treatment reduced Aβ_1–40 and stimulated neurite growth. (4) Conclusions: WE might increase ATP production after induction of mitochondrial biogenesis. Decreased Aβ_1–40 formation and enhanced ATP levels might enhance neurite growth, making WE a potential agent to enhance neuronal function and to prevent the development of AD. In this sense, WE could be a promising agent for the prevention of AD.