Brain-derived neurotrophic factor(BDNF) as a potential mechanism of the effects of acute exercise on cognitive performance

The literature shows that improvements in cognitive performance may be observed following an acute bout of exercise. However, evidence in support of the biological mechanisms of this effect is still limited. Findings from both rodent and human studies suggest brain-derived neu- rotrophic factor （BDNF） as a potential mechanism of the effect of acute exercise on memory. The molecular properties of BDNF allow this protein to be assessed in the periphery （pBDNF） （i.e., blood serum, blood plasma）, making measurements of acute exercise-induced changes in BDNF concentration relatively accessible. Studies exploring the acute exercise--pBDNF--cognitive performance relationship have had mixed findings, but this may be more reflective of methodological differences between studies than it is a statement about the role of BDNE For example, significant associations have been observed between acute exercise-induced changes in pBDNF concentration and cognitive performance in studies assessing memory, and non-significant associations have been found in studies assessing non-memory cognitive domains. Three suggestions are made for future research aimed at understanding the role of BDNF as a biological mechanism of this relationship： 1） Assessments of cognitive performance may benefit from a focus on various types of memory （e.g., relational, spatial, long-term）; 2） More finegrained measurements of pBDNF will allow for the assessment of concentrations of specific isoforms of the BDNF protein （i.e., immature, mature）; 3） Statistical techniques designed to test the mediating role of pBDNF in the acute exercise-cognitive performance relationship should be utilized in order to make causal inferences.

Correlation of serum leptin levels with anthropometric and metabolic parameters and biochemical liver function in Chinese patients with chronic hepatitis C virus infection

AIM: To determine serum leptin levels and investigate their correlations with anthropometric and metabolic parameters and biochemical liver function in patients with chronic hepatitis C virus (HCV) infection and their potential clinical implications.METHODS: Forty-two chronic HCV-infected patients without anti-viral treatment were enrolled in this study, 30 patients had chronic hepatitis C, 10 had cirrhosis, and 2 had hepatocellular carcinoma (HCC). Thirty age- and sex-matched healthy individuals served as controls. Serum leptin levels were determined by ELISA. The biochemical liver function and serum lipids were determined at the same time. The height and body weight of patients and controls were measured, and body mass index (BMI) and body fat were calculated simultaneously. The correlations of serum leptin levels with anthropometric and metabolic parameters and biochemical liver function were assessed statistically.RESULTS: The mean of serum leptin levels in patients with chronic hepatitis C, HCV-associated cirrhosis, HCVassociated HCC and control groups was (6.13±3.94),(5.25±4.21), (4.17±0.28), and (3.59±3.44) ng/mL, respectively. The serum leptin level in patients with chronic hepatitis C was significantly higher than that in controls. The serum leptin levels between cirrhotic patients and controls and between male and female cirrhotic patients had no significant difference. Serum leptin levels were positively-correlated with body fat, BMI, and apolipoprotein B (Apo B) in patients with chronic HCV infection. The serum alanine aminotransferase (ALT) levels were closelycorrelated with BMI in patients with chronic hepatitis C. CONCLUSION: HCV infection interferes with fat and lipid metabolism in patients with chronic HCV infection and leptin may play a role in hepatosteatosis.

Inocula selection in microbial fuel cells based on anodic biofilm abundance of Geobacter sulfurreducens

Microbial fuel cells （MFCs） rely on microbial conversion of organic substrates to electricity. The optimal perfor- mance depends on the establishment of a microbial community rich in electrogenic bacteria. Usually this micro- bial community is established from inoculation of the MFC anode chamber with naturally occurring mixed inocula. In this study, the electrochemical performance of MFCs and microbial community evolution were eval- uated for three inocula including domestic wastewater （DW）, lake sediment （LS） and biogas sludge （BS） with varying substrate loading （Lsub） and external resistance （Rext） on the MFC. The electrogenic bacterium Geobacter sulfurreducens was identified in all inocula and its abundance during MFC operation was positively linked to the MFC performance. The IS inoculated MFCs showed highest abundance （18% ± 1%） of G. sulfurreducens, maximum current density [Imax = （690 ± 30） mA.m 2] and coulombic efficiency （CE = 29% ±1%） with acetate as the substrate./max and CE increased to （1780 ± 30） mA.m-2 and 58%± 1%, respectively, after decreasing the Rext from 1000 Ωto 200 Ω, which also correlated to a higher abundance ofG. sulfurreducens （21% ±0.7%） on the MFC anodic biofilm. The data obtained contribute to understanding the microbial community response to Lsub and Roy, for of timizing electricity eneration in MFCs.

A New Type Machine of Mixing-molding for Polyblends

This paper introduces a new type machine for polyblends with excellent mixing capabilities of internal mixer and continuous molding character of extruder.The machine includes two functions - mixing and extrusion molding that have been composed together by rational design,so a tandem production mode - "batch + continuous" are opened up.The mathematical model of continuous mixing molding was established and verified availably by experimental research.The main physical mechanical property of vulcanizate,which had met national waterproof material standard,verified the machine practicability.The essential difference from other similar type machines is that this machine is not only suitable in producing granular and powder rubbers but also lumpish rubbers.

Performance of Spread Spectrum Watermarking in Autoregressive Host Model Under Additive White Gaussian Noise Channel

A large class of multimedia and biomedical signals can be modeled as Autotegessive （AR） random processes. Pefformance of watermarking embedding algorithms utilizing this host model is still left unexplored. The authors investigate the decoding perform-nance of Spread Spectrum （SS） embedding algorithm in the standard Additive White Gaussian Noise （AWGN） channel with the host signal being modeled as AR process. The SS embedding algorithm also use linear interference cancelation in the subspace spanned by watermark pattern. They study the influence of design parameters on the decoding performance. The analytic result is verified by Monte Carlo simulation on synthesized AR process. The result may be helpful to design watermarking system for speech, biomedical and image signals.

Researches On The Robot Obstacle Avoidance Based On Fuzzy Control

With the continuous development of modem sensor technology, coupled with the integration of artificial intelligence and a variety of emerging computer technology, it makes robots more intelligent and diverse.So the ability of the robot to complete the task is also valued and widely used.In this paper, the whole covered area of the local path planning uses a fuzzy control algorithm,which uses the robustness and an action of perception based on the biological behavior of the fuzzy control algorithm combined with itself.For obstacle avoidance system of mobile robots,we put forward the avoidance strategy of fully contacting the obstacles.And we have conducted a deep study about the theory and implementation methods.

Aurora A orchestrates entosis by regulating a dynamic MCAK-TIP150 interaction

Entosis, a ceU-in-ceU process, has been implicated in the formation of aneuploidy associated with an aberrant cell division control. Microtubule plus-end-tracking protein TI P150 facilitates the loading of MCAK onto the microtubule plus ends and orchestrates micro- tubule plus-end dynamics during cell division. Here we show that TIP150 cooperates with MCAK to govern entosis via a regulatory cir- cuitry that involves Aurora A-mediated phosphorylation of MCAK. Our biochemical analyses show that MCAK forms an intra-molecular association, which is essential for TIP150 binding. Interestingly, Aurora A-mediated phosphorylation of MCAK modulates its intra-mo- lecular association, which perturbs the MCAK-TI P150 interaction in vitro and inhibits entosis in vivo. To probe if MCAK-TIP150 inter- action regulates microtubule plasticity to affect the mechanical properties of ceUs during entosis, we used an optical trap to measure the mechanical rigidity of live MCF7 ceils. We find that the MCAK cooperates with TIP150 to promote microtubule dynamics and modulate the mechanical rigidity of the cells during entosis. Our results show that a dynamic interaction of MCAK-TI P150 orchestrated by Aurora A-mediated phosphorylation governs entosis via regulating microtubule plus-end dynamics and cell rigidity. These data reveal a previously unknown mechanism of Aurora A regulation in the control of microtubule plasticity during ceU-in-ceU pro- cesses.

Modificaomics:deciphering the functions of biomolecule modifications

The spatiotemporal expression of genes is sophisticatedly controlled through three main layers: transcriptional, translational and post-translational. Now increasing chemical modifications are discovered on genomic DNA, RNA and proteins. These modifications are recognized as additional layer of regulatory mechanisms in controlling gene expression that defines cell status. So far,more than 150 chemical modifications are identified in nucleic acids,and more than 400 discrete types of modifications are identified in proteins. How these modifications are interpreted are fundamental questions to our understanding of living organisms. The omics sciences of systems biology, including genomics, transcriptomics, proteomics, and metabolomics, have been in existence for decades. Due to the large numbers of modifications occurring in DNA, RNA and proteins with regulatory roles, we propose the modificaomics from the words of modification and omics. Modificaomics mainly refers to the comprehensive study of the modifications on DNA, RNA and proteins. In this review, we conceive modificaomics by introducing the discovered modifications in DNA, RNA and proteins as well as summarizing their biological functions. We hope the proposed modificaomics can provide a whole picture of modifications of these biopolymers and simulate the study of the functions of the modifications on DNA, RNA and proteins.

Mechanisms underlying the structural and functional characteristics of acupoints

Acupoints are particular areas on the surface of the body through which the Qi and blood of the Zang-fu organs and meridians flow.Acupoints can respond to stimuli and reflect syndromes.Research on the essential morphology of acupoints has two key focuses:anatomical structure and physiological function.The structure is the material and anatomical basis for the function,while the function is the manifestation of the structure.The two factors not only have profound significance for our understanding of the essence of acupoints,but also have great value for clinical acupuncture and moxibustion practice.Based on the structural and functional characteristics of meridians under different physiological and pathological conditions,this paper illustrates the essence of acupoints and explores the rules and biological basis of the acupoint functions induced by acupuncture and moxibustion.

Designing the mechanical properties of peptide-based supramolecular hydrogels for biomedical applications

Hydrogels are a class of special materials that contain a large amount of water and behave like rubber.These materials have found broad applications in tissue engineering,cell culturing,regenerative medicine etc.Recently,the exploration of peptide-based supramolecular hydrogels has greatly expanded the repertoire of hydrogels suitable for biomedical applications.However,the mechanical properties of peptide-based hydrogels are intrinsically weak.Therefore,it is crucial to develop methods that can improve the mechanical stability of such peptide-based hydrogels.In this review,we explore the factors that determine or influence the mechanical stability of peptide-based hydrogels and summarize several key elements that may guide scientists to achieve mechanically improved hydrogels.In addition,we exemplified several methods that have been successfully developed to prepare hydrogels with enhanced mechanical stability.These mechanically strong peptide-based hydrogels may find broad applications as novel biomaterials.It is still challenging to engineer hydrogels in order to mimic the mechanical properties of biological tissues.More hydrogel materials with optimal mechanical properties suitable for various types of biological applications will be available in the near future.

Total chemical and semisynthetic approaches for the preparation of ubiquitinated proteins and their applications

Protein ubiquitination is an important post-translational modification(PTM) in eukaryotic organisms that regulates a variety of cellular processes, such as protein degradation, signal transduction, apoptosis, and DNA damage tolerance. To decipher mechanistically the diverse biological functions of ubiquitination, homogeneous ubiquitinated proteins are greatly needed.Although direct isolation from cell source and in vitro enzymatic methods can be used to produce such proteins, these methods often suffer from problems of low yield or heterogeneous products. Comparably, total chemical and semisynthetic approaches offer good alternatives to produce the ubiquitinated proteins with high purity and selectivity. This review summarizes the recent developments of protein ubiquitination strategies and the use of the synthesized proteins to help garner structural and functional insight into the inner workings of the ubiquitin system.