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In this work, a four-dimensional fractional order hyperchaotic system with coexisting attractors is excogitated. The stability analysis of the equilibrium point is investigated, and the chaotic and hyperchaotic behavior of the system is well demonstrated numerically by the Lyapunov exponents. By applying delayed feedback control technique, we obtain the existence condition of Hopf bifurcation for the such system. Some numerical simulations are exhibited to substantiate the obtained results in the end, which also displays some interesting dynamical phenomena, such as quasi-periodic, and hyperchaotic. The work reveals that the fractional order and delays have a great significance to controlling the hyperchaotic system. [ABSTRACT FROM AUTHOR]

Although structures of vitrified supramolecular complexes have been determined at near-atomic resolution, elucidating in situ molecular structure in living cells remains a challenge. Here, we report a straightforward liquid cell technique, originally developed for real-time visualization of dynamics at a liquid-gas interface using transmission electron microscopy, to image wet biological samples. Due to the scattering effects from the liquid phase, the micrographs display an amplitude contrast comparable to that observed in negatively stained samples. We succeed in resolving subunits within the protein complex GroEL imaged in a buffer solution at room temperature. Additionally, we capture various stages of virus cell entry, a process for which only sparse structural data exists due to their transient nature. To scrutinize the morphological details further, we used individual particle electron tomography for 3D reconstruction of each virus. These findings showcase this approach potential as an efficient, cost-effective complement to other microscopy technique in addressing biological questions at the molecular level. Electron microscopy of native hydrated biological samples close to physiological temperature is challenging. Here, authors encapsulate proteins and cells as an efficient, cost-effective complement to other microscopy technique in addressing biological questions at the molecular level. [ABSTRACT FROM AUTHOR]

In recent years, distributed energy has been gradually applied in residential electricity consumption, and smart devices have been rapidly developed among residential households. This paper establishes a model of optimal scheduling system for building load, taking into account the needs of grid side and customer side, and takes the total cost of electricity consumption and total deviation of electricity consumption of building residents as the optimization objectives. Then, a multi-objective equilibrium optimizer algorithm integrated competition mechanism (CMOEO) is proposed to solve the multi-objective optimization scheduling problem of building loads with multi-decision variables. The algorithm is improved from the equilibrium optimizer algorithm by introducing the competition mechanism, replacing the original exploration and exploitation constant coefficients with dynamic factors and integrating differential evolution. Through the comparison experiments of different algorithms and the different capacity of photovoltaic energy storage system (PESS), the results show that the CMOEO has fast convergence speed, strong merit-seeking ability and better population diversity. In addition, the configuration of PESS is conducive to reducing the cost of electricity for building residents and playing the role of peak-shaving and valley-filling. [ABSTRACT FROM AUTHOR]

Succinate dehydrogenase, which is known as mitochondrial complex II, has proven to be a fascinating machinery, attracting renewed and increased interest in its involvement in human diseases. Herein, we find that succinate dehydrogenase assembly factor 4 (SDHAF4) is downregulated in cardiac muscle in response to pathological stresses and in diseased hearts from human patients. Cardiac loss of Sdhaf4 suppresses complex II assembly and results in subunit degradation and complex II deficiency in fetal mice. These defects are exacerbated in young adults with globally impaired metabolic capacity and activation of dynamin-related protein 1, which induces excess mitochondrial fission and mitophagy, thereby causing progressive dilated cardiomyopathy and lethal heart failure in animals. Targeting mitochondria via supplementation with fumarate or inhibiting mitochondrial fission improves mitochondrial dynamics, partially restores cardiac function and prolongs the lifespan of mutant mice. Moreover, the addition of fumarate is found to dramatically improve cardiac function in myocardial infarction mice. These findings reveal a vital role for complex II assembly in the development of dilated cardiomyopathy and provide additional insights into therapeutic interventions for heart diseases. Functional succinate dehydrogenase (SDH) complex is vital to mitochondrial homeostasis. Here the authors show that disruption of SDH assembly in the heart causes dilated cardiomyopathy via impairing the mitochondrial integrity and metabolism and that mitochondrial interventions can be an effective approach to ameliorate the disease progression. [ABSTRACT FROM AUTHOR]

Sound absorption mechanism, material modification and structural design of various synthetic fiber materials for industrial noise reduction are reviewed in this paper for the problems of low sound absorption coefficient (SAC) and narrow frequency band of porous materials. Delany-Bazley model and Johnson-Champoux-Allard (JCA) model are widely used to predict the SAC, but they are slightly different. The air viscous effect plays an important role in Delany-Bazley model and its modified forms, while JCA model and its modified forms consider the effect of thermal conduction in addition to air viscosity. In addition, synthetic fiber materials such as polymers, metal fibers and inorganic fibers are widely used in noise reduction fields of various industries due to their unique acoustic and mechanical performance. Acoustic properties of polymers are usually improved by adding fillers, using perforated structures, gradient porous structures, and multilayer composite structures. And improving preparation method, increasing thickness of back cavity, combining different pore sizes, developing new composite materials, and adopting perforation technology can greatly promote the engineering application of metal fibers in extreme environments. Common methods to improve the sound absorption performance of inorganic fibers are to modify preparation method, increase thickness of materials and research composite materials. [ABSTRACT FROM AUTHOR]

In present engineering applications, calculations of hydraulic properties in two-phase flow are still highly dependent on empirical or semi-empirical equations obtained from experiments. However, the empirical equations that can reproduce the experiment data on a certain fracture specimen may have errors on other specimens. Researchers have obtained results that show quite different evolution forms of hydraulic characteristics of two-phase flow, which is induced by the variety of the influencing factors in two-phase flow. This paper aims at expanding the experimental results on the hydraulic characteristics of two-phase flow in rock fractures. With a newly developed experiment system, visualized two-phase flow experiments were introduced. The difference in the surface morphology of the fractures leads to totally different flow structures, which indicates the role of capillary pressure differs due to different fracture surfaces. The relative permeability in the rough specimen approximately follows the Corey model, which confirmed that the pressure drop is in this rough fracture is dominated by the capillary pressure, but the relative permeability is not only the function of saturation, but also the function of water flow velocities. However, the relative permeability is not perfect for evaluating the difference of two-phase hydraulic characteristics induced by the fracture surface morphology. On the contrary, the Lockhart-Martinelli model is appropriate for evaluating the difference in the two-phase hydraulic characteristics between the smooth fracture and the rough fracture, which indicates that the two-phase flow turbulence is obviously increased by the fracture roughness. [ABSTRACT FROM AUTHOR]

Rock mass quality assessment has a vital influence on the excavation of tunnels and caverns in rock mass. For this purpose, extensive field studies, including records of measure-while-drilling data and rock mass quality scores (RQS) from the observation reports of tunnel faces, have been conducted. In order to predict RQS, three optimized artificial neural network (ANN) models based on genetic algorithm (GA), particle swarm optimization (PSO), and imperialist competition algorithm (ICA) were developed. Six parameters of measure-while-drilling (MWD) data and their corresponding RQS constituted 1270 datasets, which were set as input and output of ANN, respectively. The traditional multiple linear regression (MLR), multiple nonlinear regression (MNR) statistical model, and ANN model were developed as comparative models. Comparison results reveal that PSO-ANN and ICA-ANN models are capable of predicting RQS with higher reliability than the MLR, MNR, ANN, and GA-ANN models. Results indicate that PSO-ANN and ICA-ANN models can be used to predict RQS; however, the PSO-ANN model has better performance. [ABSTRACT FROM AUTHOR]

This paper is concerned with a class of fractional neutral stochastic integro-differential equations with impulses driven by fractional Brownian motion (fBm). First, by means of the resolvent operator technique and contraction mapping principle, we can directly show the existence and uniqueness result of mild solution for the aforementioned system. Then we develop a new impulsive-integral inequality to obtain the global attracting set and pth moment exponential stability for this type of equation. Worthy of note is that this powerful inequality after little modification is applicable to the case with delayed impulses. Moreover, sufficient conditions which guarantee the pth moment exponential stability for some pertinent systems are stated without proof. In the end, an example is worked out to illustrate the theoretical results. [ABSTRACT FROM AUTHOR]

This paper proposes an opportunistic routing with data fusion (ORDF) protocol for the widely used multi-source wireless sensor networks in which the spatial-temporal correlation among sensory data is ubiquitous. In the ORDF protocol, a new routing metric, which considers the data fusion and expected any-path transmissions, is presented to select a next-hop forwarding node that could save the maximal amount of energy. A candidate set selection algorithm is proposed to find the optimal candidate set of each node. An ACK-based coordination method among candidates is also given for the design of the ORDF protocol. Simulation results show that the ORDF protocol can greatly improve the network lifetime and reduce the network delay compared to general opportunistic routing protocol, such as ExOR, EEOR and OAPF. With increase of the number of source nodes, the ORDF protocol has more significant advantages in prolonging the network lifetime and reducing the network delay. [ABSTRACT FROM AUTHOR]

The physical and mechanical change processes of rock are closely related to energy transformation, and its deformation and failure is an instability phenomena driven by energy exchange. This study investigated mechanism of shear deformation, failure and energy dissipation of joint using both physical and numerical direct shear tests under constant normal load (CNL) condition. Three kinds of joint surface were artificially prepared. An acoustic emission system was employed to monitor acoustic emission in physical test, and rupture frequency was recorded in numerical test to represent micro-crack development. By research of numerical micro-crack development accompanied with physical acoustic emission results, mechanism of shear deformation and failure of joints were illustrated schematically. By definition of dissipation energy, captured using the particle flow code (PFC2D), energy releasing and dissipation were discussed with microscopic damage evolution of joints. Results showed that joints under shearing present a dissipation trend of four stages including a slow rise stage, a rapid rise stage, a shock rise stage and a rapid decline stage. [ABSTRACT FROM AUTHOR]

Variations in mitochondrial DNA (mtDNA) have been fundamental for understanding human evolution and are causative for a plethora of inherited mitochondrial diseases, but the mutation signatures of germline mtDNA and their value in understanding mitochondrial pathogenicity remain unknown. Here, we carried out a systematic analysis of mutation patterns in germline mtDNA based on 97,566 mtDNA variants from 45,494 full-length sequences and revealed a highly non-stochastic and replication-coupled mutation signature characterized by nucleotide-specific mutation pressure (G > T>A > C) and position-specific selection pressure, suggesting the existence of an intensive mutation–selection interplay in germline mtDNA. We provide evidence that this mutation–selection interplay has strongly shaped the mtDNA sequence during evolution, which not only manifests as an oriented alteration of amino acid compositions of mitochondrial encoded proteins, but also explains the long-lasting mystery of CpG depletion in mitochondrial genome. Finally, we demonstrated that these insights may be integrated to better understand the pathogenicity of disease-implicated mitochondrial variants. [ABSTRACT FROM AUTHOR]

To study shear failure, acoustic emission counts and characteristics of bolted jointed rock-like specimens are evaluated under compressive shear loading. Model joint surfaces with different roughnesses are made of rock-like material (i.e. cement). The jointed rock masses are anchored with bolts with different elongation rates. The characteristics of the shear mechanical properties, the failure mechanism, and the acoustic emission parameters of the anchored joints are studied under different surface roughnesses and anchorage conditions. The shear strength and residual strength increase with the roughness of the anchored joint surface. With an increase in bolt elongation, the shear strength of the anchored joint surface gradually decreases. When the anchored structural plane is sheared, the ideal cumulative impact curve can be divided into four stages: initial emission, critical instability, cumulative energy, and failure. With an increase in the roughness of the anchored joint surface, the peak energy rate and the cumulative number of events will also increase during macro-scale shear failure. With an increase in the bolt elongation, the energy rate and the event number increase during the shearing process. Furthermore, the peak energy rate, peak number of events and cumulative energy will all increase with the bolt elongation. The results of this study can provide guidance for the use of the acoustic emission technique in monitoring and predicting the static shear failure of anchored rock masses. [ABSTRACT FROM AUTHOR]

Amyloid-β (Aβ) is widely recognized as toxic to neuronal cells. Its deposition on plasma and intracellular membranes and aggregation into amyloid plaques can disturb the composition and physiological function of neurons. Whether a physical property of cells, such as stiffness, is altered by endogenously overexpressed Aβ has not yet been investigated. In this study, we used human neuroblastoma cells stably overexpressing amyloid precursor protein (APP) and its Swedish mutant form (APPswe) to measure the changes in cell stiffness. Our results showed that the stiffness of cells overexpressing APP or APPswe was higher than that of control SH-SY5Y cells. Either reducing levels of Aβ with the γ secretase inhibitor DAPT or blocking the membrane calcium channel formed by Aβ with tromethamine decreased cell stiffness to a level close to the control SH-SY5Y cells. Our results suggested that Aβ, not APP, contributed to increased cell stiffness and that closure of calcium channels formed by Aβ can alleviate the effects of Aβ on membrane stiffness. [ABSTRACT FROM AUTHOR]

The materials with different moduli in tension and compression are called bi-modulus materials. Graphene is such a kind of materials with the highest strength and the thinnest thickness. In this paper, the mechanical response of the bi-modulus beam subjected to the temperature effect and placed on the Winkler foundation is studied. The differential equations about the neutral axis position and undetermined parameters of the normal strain of the bi-modulus foundation beam are established. Then, the analytical expressions of the normal stress, bending moment, and displacement of the foundation beam are derived. Simultaneously, a calculation procedure based on the finite element method (FEM) is developed to obtain the temperature stress of the bi-modulus structures. It is shown that the obtained bi-modulus solutions can recover the classical modulus solution, and the results obtained by the analytical expressions, the present FEM procedure, and the traditional FEM software are consistent, which verifies the accuracy and reliability of the present analytical model and procedure. Finally, the difference between the bi-modulus results and the classical same modulus results is discussed, and several reasonable suggestions for calculating and optimizing the certain bi-modulus member in practical engineering are presented. [ABSTRACT FROM AUTHOR]

Aims/hypothesis: O-GlcNAcylation is implicated in modulating mitochondrial function, which is closely involved in regulating muscle metabolism. The presence of O-GlcNAcase (OGA), the enzyme involved in the removal of O-GlcNAc, in mitochondria was recently confirmed in rats. In the present study, we investigated the regulation of myogenesis and muscle insulin sensitivity to OGA in mice, with a focus on mitochondria. Methods: C57BL/6J mice fed a high-fat diet for 4 months were used to observe mitochondrial density, activity and O-GlcNAcylation in muscle. Small interfering RNA and overexpression vectors were used to modulate protein content in vitro. Results: High-fat feeding decreased the OGA level and largely increased mitochondrial O-GlcNAcylation in mouse skeletal muscle that was accompanied by decreased levels of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), decreased mitochondrial density and disrupted mitochondrial complex activities. Knockdown of OGA in C2C12 myoblasts promoted PGC-1α degradation, resulting in the suppression of mitochondrial biogenesis and myogenesis, whereas neither knockdown of O-GlcNAc transferase nor overexpression of OGA had significant effects on myogenesis. Mitochondrial dysfunction as evidenced by decreased ATP content and increased reactive oxygen species production, and increased lipid and protein oxidation was observed in both myoblasts and myotubes after OGA knockdown. Meanwhile, elevated O-GlcNAcylation through either OGA knockdown or treatment with the OGA inhibitor PUGNAc and the O-GlcNAc transferase substrate d-GlcNAc suppressed myotube insulin signalling transduction and glucose uptake. OGA overexpression had no significant effect on insulin sensitivity but sufficiently improved the insulin resistance induced by d-GlcNAc treatment. Conclusions/interpretation: These data suggest that OGA can modulate mitochondrial density via PGC-1α and mitochondrial function via protein O-GlcNAcylation. In this manner, OGA appears to play a key role in myogenesis and the development of muscle insulin resistance. [ABSTRACT FROM AUTHOR]

Superparamagnetic iron oxide nanoparticles (IONPs) have been widely applied in numerous biomedical fields. The evaluation of the toxicity of IONPs to the environment and human beings is indispensable to guide their applications. IONPs are usually considered to have good biocompatibility; however, some literatures have reported the toxicity of IONPs in vitro and in vivo. The controversy surrounding the biocompatibility of IONPs prompted us to carefully consider the biological effects of IONPs, especially under stress conditions. However, the potential risks of IONPs under stress conditions have not yet been evaluated in depth. Acrolein is widespread in the environment and modulates stress-induced gene activation and cell death in many organs and tissues. In this study, we assessed the sensitivity of H9c2 cardiomyocyte cells embedded with IONPs to acrolein and investigated the possible molecular mechanisms involved in this sensitivity. IONPs, which alone exhibited no toxicity, sensitized the H9c2 cardiomyocytes to acrolein-induced dysfunction. The IONP/acrolein treatment induced a loss of viability, membrane disruption, reactive oxygen species (ROS) generation, Erk activation, mitochondrial and lysosomal dysfunction, and necrosis in H9c2 cells. Treatment with an ROS generation inhibitor (diphenyleneiodonium) or an iron chelator (deferoxamine) prevented the IONP/acrolein-induced loss of viability, suggesting that ROS and IONP degradation facilitated the toxicity of the IONP/acrolein treatment in H9c2 cells. Our data suggest that cells embedded in IONPs are more vulnerable to oxidative stress, which confirms the hypothesis that nanoparticles can sensitize cells to the adverse effects of external stimulation. The present work provides a new perspective from which to evaluate the interactions between nanoparticles and cells. [ABSTRACT FROM AUTHOR]

These authors contributed equally: Xueqiang Wang, Xing Zhang, Ke Cao, Mengqi Zeng, Xuyang Fu. Correction to: I Nature Communications i https://doi.org/10.1038/s41467-022-31548-1, published online 08 July 2022 The original version of this Article omitted from the author list the 17th author Feng Gao, who is from the Key Laboratory of Aerospace Medicine of the Ministry of Education, School of Aerospace Medicine, Fourth Military Medical University, Xi'an, 710032, China. [Extracted from the article]

Prostate carcinoma is one of the leading causes of cancer-related morbidity and mortality in males in western countries. Curcumin exhibits growth-suppressive activity against several cancers, including prostate cancer, but it has poor bioavailability. The purpose of this study was to evaluate the anticancer potency and mechanism of a curcumin analogue, 1,5-bis(3-hydroxyphenyl)-1,4-pentadiene-3-one (Ca 37), in human prostate cancer. Studies were performed in established human prostate cancer cell lines (PC-3 and DU145) as well as in a murine xenograft tumor (PC-3) model. Ca 37 presented a preferential suppression capacity against growth and migration toward prostate cancer cells compared with curcumin. Ca 37 impaired the bioenergetics system, promoted cell cycle arrest and apoptosis activation in PC-3 cells. In addition, 0.5 μmol (6.65 mg/kg body weight) of Ca 37 significantly inhibited the growth of the prostate xenografted tumors, whereas 6 μmol (110 mg/kg body weight) of curcumin had little effect. Furthermore, a combination of Ca 37 and curcumin resulted in enhanced antitumor activity in prostate cancer cells. N-Acetylcysteine abrogated both reactive oxygen species (ROS) production and viability loss induced by Ca 37 but partially prevented growth inhibition in PC-3 cells treated with curcumin alone, or a combination with Ca 37. The data indicate that induction of ROS plays a vital role in the growth inhibitory effect of Ca 37 in PC-3 cells. This study suggests that Ca 37, alone or in combination with curcumin, may be a promising anticancer agent for prostate cancer therapy. [ABSTRACT FROM AUTHOR]

An acetonitrile-salt stacking method was established for the assay of lipoic acid (LA) in biological samples. Samples were deproteinized with acetonitrile at a final concentration of 60 % (v/v) and then injected hydrodynamically at 3.45 × 10 Pa for 180.0 s. The optimum background electrolyte was found to be 90.0 mmol L pH 9.1 borate buffer. LA could be detected within 35 min at +7.0 kV with satisfactory repeatability (relative standard deviations, RSDs, of migration times and peak areas were both below 10 % for intraday and interday; n = 6/9) and a relatively low limit of detection of ca. 0.5 μmol L. [ABSTRACT FROM AUTHOR]

Cigarette smoking causes various diseases, including lung cancer and cardiovascular disease, and reduces life span, though the mechanisms are not well understood. We hypothesize that smoking may cause cellular mitochondrial dysfunction and oxidative stress, leading to aging acceleration. In the present study, we tested the effects of acrolein, a major representative smoking toxicant, on human lung fibroblast IMR-90 cells with regard to cellular senescence, oxidative stress, and mitochondrial function. The results showed that subacute treatment with low dose of acrolein induces the following events compared to the control cells: cell senescence demonstrated by increases in the activity of β-galactosidase, the higher expression of p53 and p21, decreases in DNA synthesis, Sirt1 expression, and telomere length; oxidative stress occurred as the increases in the production of reactive oxygen species, DNA damage, and protein oxidation; and mitochondrial dysfunction shown as decreases in the mitochondrial membrane potential, mitochondrial biogenesis regulator PGC-1 alpha and mitochondria complex I, II, III, and V. These results suggest that acrolein may accelerate aging through the mechanism of increasing oxidative stress and mitochondrial dysfunction. [ABSTRACT FROM AUTHOR]

We developed a complex dietary supplement designed to offset five key mechanisms of aging and tested its effectiveness in ameliorating age-related cognitive decline using a visually cued Morris water maze test. All younger mice (<1 year old) learned the task well. However, older untreated mice (>1 year) were unable to learn the maze even after 5 days, indicative of strong cognitive decline at older ages. In contrast, no cognitive decline was evident in older supplemented mice, even when ∼2 years old. Supplemented older mice were nearly 50% better at locating the platform than age-matched controls. Brain weights of supplemented mice were significantly greater than controls, even at younger ages. Reversal of cognitive decline in activity of complexes III and IV by supplementation was significantly associated with cognitive improvement, implicating energy supply as one possible mechanism. These results represent proof of principle that complex dietary supplements can provide powerful benefits for cognitive function and brain aging. [ABSTRACT FROM AUTHOR]

The ecosystem of the Three Gorges in the Yangtze River was changed into an artificial lake (reservoir) ecosystem after impoundment in June 2003. We surveyed the seasonal variation and spatial distribution of copepods from April 2004 to January 2005 in order to provide data for clarifying the successional pattern of the ecosystem. From Jiangjin to Maoping, eight copepod species were collected and classified into Calanoida (2), Harpacticoida (1), and Cyclopoida (5). Among them, Mesocyclops pehpeiensis, M. leuckarti and Sinocalanus dorrii had a relatively wide distribution. No distinct difference in species number was found among the sampling sites, but the species composition was different. Species composition, distribution and density of copepods showed significant seasonal variations. In addition, copepod density showed an obvious gradient with the distance from the reservoir dam: the nearer to the dam, the denser the copepods. [ABSTRACT FROM AUTHOR]

d-Galactose ( d-gal) -induced aging models in Drosophila, houseflies, mice and rats have been widely used; however, the underlying mechanisms are poorly understood. To investigate the involvement of mitochondrial dysfunction of d-gal, mitochondrial function was examined in the brain and liver of C57BL/6J mice, subjected to a treatment of d-gal with or without a concomitant treatment with a mitochondrial nutrient, R-alpha-lipoic acid (LA). d-Gal treatment induced a significant decrease in succinate-linked respiratory control ratio (RCR) and ADP/O ratio in the liver and brain, and also a significant increase in the maximum velocity (Vmax) and substrate binding affinity (Km) of complex II in the liver. LA treatment to d-gal-injected animals restored mitochondrial RCR in both brain and liver, ADP/O and Km of complex II in the liver. These results suggest LA is effective in delaying d-gal toxicity by ameliorating mitochondrial dysfunction. [ABSTRACT FROM AUTHOR]

Excess weight gain is a major cause of increased blood pressure in most patients with essential hypertension, and also greatly increases the risk for renal disease. Obesity raises blood pressure by increasing renal tubular reabsorption, impairing pressure natriuresis, causing volume expansion due to activation of the sympathetic nervous system and renin-angiotensin system, and by physical compression of the kidneys, especially when visceral obesity is present. The mechanisms of sympathetic nervous system activation in obesity may be due, in part, to hyperleptinemia that stimulates the hypothalamic pro-opiomelanocortin pathway. With prolonged obesity, there may be a gradual loss of nephron function that worsens with time and exacerbates hypertension. Weight reduction is an essential first step in the management of obesity hypertension and renal disease. Special considerations for the obese patient, in addition to adequately controlling the blood pressure, include correction of the metabolic abnormalities and protection of the kidneys from further injury. [ABSTRACT FROM AUTHOR]

Stress may contribute to aging acceleration and age-related degenerative diseases. Stress and adaptation to stress require numerous homeostatic adjustments including hormones, neurotransmitters, oxidants, and other mediators. The stress-induced hormones, neurotransmitters, and oxidants all have beneficial, but also harmful effects if out of balance. Therefore, the homeostasis of stress and adaptation should be governed by the hormone balance, neurotransmitter balance, and oxidant balance, as well as the interactions among these substances. The imbalance and the over-interaction of these balances may ultimately cause increased oxidant generation and oxidative damage to biomolecules. This increased oxidative damage may add to the oxidant burden associated with normal aerobic metabolism, which in itself, generates oxidants, causes accumulation of oxidative damage in mitochondria, and contributes to normal aging. Therefore, the stress-associated increase of oxidative damage may, in part, contribute to stress-associated aging acceleration and age-related neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

We studied the levels of free radicals, lipid peroxides and antioxidants, as well as superoxide dismutase (SOD) activity in the blood of six patients with myotonic dystrophy (MyD) (mean age 52.8, SD 5.0 years) and seven controls (mean age 48.8, SD 6.3 years). Electron spin resonance was used to assess the free radicals by the spin-trapping method using 5,5-dimethyl-l-pyrroline-l-oxide. The levels of C centre radical ( P < 0.05) and H radical ( P < 0.05) in blood from the six MyD patients were significantly higher than those in the seven controls. The SOD activities in red blood cells and serum from the six MyD patients showed no significant difference from those in the seven controls. The serum lipid peroxide concentration was increased in five of the MyD patients and tended to increase further as the disease progressed. The serum vitamin E level was low in two patients and in the low normal range in three. Serum coenzyme Q was decreased in four patients. The serum selenium level was decreased in two patients and that of serum albumin was decreased in three. Therefore we conclude that increased levels of free radicals and lipid peroxides and decreased antioxidant levels play an important role in the pathogenesis of MyD. [ABSTRACT FROM AUTHOR]

This study describes, using electron spin resonance spectrometry/spin trapping technique, the increase superoxide dismutase (SOD) activity in the mitochondrial and cytosolic fraction of the cortex, midbrain, pons-medulla oblongata and cerebellum, and in thiobarbituric acid-reactive substances (TBARS) in the cortex, cerebellum and hippocampus of the aged rats. The results show that corresponding to the increased life span and improved physical conditions observed after peroral long-term treatment with Bio-catalyzer, a commercial natural fermented health food supplement marketed in Japan and in the Philippines and earlier reported to be a hydroxyl radical scavenger with weaker scavenging activity on superoxide radical (O), SOD which is involved in the metabolic degradation of O was further increased, whereas TBARS decreased. These findings suggest that the increased SOD activity in the brain as a defense mechanism against age-related accumulation of reactive oxygen species, in particular superoxide radicals, was enhanced with Biocatalyzer treatment while age-related peroxidation of neuronal membrane, as measured by TBARS, was decreased. [ABSTRACT FROM AUTHOR]

Density is the most important parameter of debris flow. This work looks into the typical debris flow and mountain torrent occurred in Longmen Mountains in the past 20 years and compares the calculation results of the density using various methods. It shows that the mean deviations of result are in the range of 20–30%, and the static model is only suitable to the occurred debris flow event but not the forecast. Based on the analysis of typical rainfall debris flow, the influence factors of density are revealed; it shows that the density is controlled by the form conditions and the soil-water coupling process of debris flow. A function is introduced to describe the activity of material source, which defined by volume and relative elevation of materials, and the watershed area. The forecast model is established by the relationship between the density and its influence factors. When the new method is applied to the Longmen mountain area and the upper basin of the Minjiang River, although there are still few discretization errors, the results still can explain nearly 95% of the evolution trend, which shows that the new method is not compromised by regional differences. [ABSTRACT FROM AUTHOR]

Psoriasis is a chronic inflammatory skin disease with high morbidity, poor treatment methods and high rates of relapse. Keratinocyte hyperproliferation and shortened cell cycles are important pathophysiological features of psoriasis. As a known oncogene, Yes-associated protein (YAP) plays a role in promoting cell proliferation and inhibiting cell apoptosis; however, whether YAP is involved in the pathogenesis of psoriasis remains to be determined. Amphiregulin (AREG), a transcriptional target of YAP, was found to be upregulated in psoriasis, and overexpression of AREG promoted keratinocyte proliferation. In the present study, immunohistochemistry showed that YAP expression was elevated in the skin of psoriasis patients and in the Imiquimod (IMQ) mouse model of psoriasis. Knockdown of YAP in HaCaT cells inhibited cell proliferation, caused cell cycle arrest in G0/G1 phase and promoted apoptosis. These changes in YAP-knockdown HaCaT cells were related to changes in AREG expression. We concluded that YAP may play an important role in the regulation of abnormal keratinocyte proliferation via an AREG-dependent pathway and that YAP could be a new target in the treatment of psoriasis. [ABSTRACT FROM AUTHOR]

Obesity is associated with an increasing prevalence of cardiovascular diseases and metabolic syndrome. It is of paramount importance to reduce obesity-associated cardiac dysfunction and impaired energy metabolism. In this study, the activation of the AMP-activated protein kinase (AMPK) pathway by punicalagin (PU), a major ellagitannin in pomegranate was investigated in the heart of a rat obesity model. In male SD rats, eight-week administration of 150 mg/kg pomegranate extract (PE) containing 40% punicalagin sufficiently prevented high-fat diet (HFD)-induced obesity associated accumulation of cardiac triglyceride and cholesterol as well as myocardial damage. Concomitantly, the AMPK pathway was activated, which may account for prevention of mitochondrial loss via upregulating mitochondrial biogenesis and amelioration of oxidative stress via enhancing phase II enzymes in the hearts of HFD rats. Together with the normalized expression of uncoupling proteins and mitochondrial dynamic regulators, PE significantly prevented HFD-induced cardiac ATP loss. Through in vitro cultures, we showed that punicalagin was the predominant component that activated AMPK by quickly decreasing the cellular ATP/ADP ratio specifically in cardiomyocytes. Our findings demonstrated that punicalagin, the major active component in PE, could modulate mitochondria and phase II enzymes through AMPK pathway to prevent HFD-induced cardiac metabolic disorders. [ABSTRACT FROM AUTHOR]