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101.
Maria Grazia Tupone Gloria Panella Michele dAngelo Vanessa Castelli Giulia Caioni Mariano Catanesi Elisabetta Benedetti Annamaria Cimini 《International journal of molecular sciences》2021,22(23)
Thanks to their reduced size, great surface area, and capacity to interact with cells and tissues, nanomaterials present some attractive biological and chemical characteristics with potential uses in the field of biomedical applications. In this context, graphene and its chemical derivatives have been extensively used in many biomedical research areas from drug delivery to bioelectronics and tissue engineering. Graphene-based nanomaterials show excellent optical, mechanical, and biological properties. They can be used as a substrate in the field of tissue engineering due to their conductivity, allowing to study, and educate neural connections, and guide neural growth and differentiation; thus, graphene-based nanomaterials represent an emerging aspect in regenerative medicine. Moreover, there is now an urgent need to develop multifunctional and functionalized nanomaterials able to arrive at neuronal cells through the blood-brain barrier, to manage a specific drug delivery system. In this review, we will focus on the recent applications of graphene-based nanomaterials in vitro and in vivo, also combining graphene with other smart materials to achieve the best benefits in the fields of nervous tissue engineering and neural regenerative medicine. We will then highlight the potential use of these graphene-based materials to construct graphene 3D scaffolds able to stimulate neural growth and regeneration in vivo for clinical applications. 相似文献
102.
Marie Bisconti Jean-Franois Simon Sarah Grassi Baptiste Leroy Baptiste Martinet Vanessa Arcolia Vladimir Isachenko Elise Hennebert 《International journal of molecular sciences》2021,22(23)
Male infertility is a common health problem that can be influenced by a host of lifestyle risk factors such as environment, nutrition, smoking, stress, and endocrine disruptors. These effects have been largely demonstrated on sperm parameters (e.g., motility, numeration, vitality, DNA integrity). In addition, several studies showed the deregulation of sperm proteins in relation to some of these factors. This review inventories the literature related to the identification of sperm proteins showing abundance variations in response to the four risk factors for male infertility that are the most investigated in this context: obesity, diabetes, tobacco smoking, and exposure to bisphenol-A (BPA). First, we provide an overview of the techniques used to identify deregulated proteins. Then, we summarise the main results obtained in the different studies and provide a compiled list of deregulated proteins in relation to each risk factor. Gene ontology analysis of these deregulated proteins shows that oxidative stress and immune and inflammatory responses are common mechanisms involved in sperm alterations encountered in relation to the risk factors. 相似文献
103.
Dietary Mannan Oligosaccharides Modulate Gut Microbiota,Increase Fecal Bile Acid Excretion,and Decrease Plasma Cholesterol and Atherosclerosis Development
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Lisa R. Hoving Saeed Katiraei Marieke Heijink Amanda Pronk Lianne van der Wee‐Pals Trea Streefland Martin Giera Ko Willems van Dijk Vanessa van Harmelen 《Molecular nutrition & food research》2018,62(10)
1 Scope
Mannan oligosaccharides (MOS) have proven effective at improving growth performance, while also reducing hyperlipidemia and inflammation. As atherosclerosis is accelerated both by hyperlipidemia and inflammation, we aim to determine the effect of dietary MOS on atherosclerosis development in hyperlipidemic ApoE*3‐Leiden.CETP (E3L.CETP) mice, a well‐established model for human‐like lipoprotein metabolism.2 Methods and results
Female E3L.CETP mice were fed a high‐cholesterol diet, with or without 1% MOS for 14 weeks. MOS substantially decreased atherosclerotic lesions up to 54%, as assessed in the valve area of the aortic root. In blood, IL‐1RA, monocyte subtypes, lipids, and bile acids (BAs) were not affected by MOS. Gut microbiota composition was determined using 16S rRNA gene sequencing and MOS increased the abundance of cecal Bacteroides ovatus. MOS did not affect fecal excretion of cholesterol, but increased fecal BAs as well as butyrate in cecum as determined by gas chromatography mass spectrometry.3 Conclusion
MOS decreased the onset of atherosclerosis development via lowering of plasma cholesterol levels. These effects were accompanied by increased cecal butyrate and fecal excretion of BAs, presumably mediated via interactions of MOS with the gut microbiota. 相似文献104.
105.
Vanessa Boritzki Harald Hübner Anni Allikalt Peter Gmeiner Birgitta M. Whrl 《International journal of molecular sciences》2021,22(16)
The human dopamine receptors D2S and D3 belong to the group of G protein-coupled receptors (GPCRs) and are important drug targets. Structural analyses and development of new receptor subtype specific drugs have been impeded by low expression yields or receptor instability. Fusing the T4 lysozyme into the intracellular loop 3 improves crystallization but complicates conformational studies. To circumvent these problems, we expressed the human D2S and D3 receptors in Escherichia coli using different N- and C-terminal fusion proteins and thermostabilizing mutations. We optimized expression times and used radioligand binding assays with whole cells and membrane homogenates to evaluate KD-values and the number of receptors in the cell membrane. We show that the presence but not the type of a C-terminal fusion protein is important. Bacteria expressing receptors capable of ligand binding can be selected using FACS analysis and a fluorescently labeled ligand. Improved receptor variants can thus be generated using error-prone PCR. Subsequent analysis of clones showed the distribution of mutations over the whole gene. Repeated cycles of PCR and FACS can be applied for selecting highly expressing receptor variants with high affinity ligand binding, which in the future can be used for analytical studies. 相似文献
106.
Karima Benaissi Virgil Hlaine Vanessa Prvot Claude Forano Laurence Hecquet 《Advanced Synthesis \u0026amp; Catalysis》2011,353(9):1497-1509
Transketolase (TK) from S. cerevisiae was successfully immobilized on layered double hydroxides (LDH) using simple, affordable and efficient adsorption and coprecipitation based immobilization procedures. Optimization of the preparation was performed using zinc aluminium nitrate (Zn2Al‐NO3) and magnesium aluminium nitrate (Mg2Al‐NO3) LDH as immobilization supports, and the protein‐to‐LDH weight ratio (Q) was varied. The highest immobilization yields (98–99%) and highest relative specific activities (4.2–4.4 U⋅mg−1 for the immobilized enzyme compared to 4.5 U⋅mg−1 for the free enzyme) were both achieved when using a protein‐to‐LDH weight ratio (Q) of 0.38. Efficient lyophilization of the LDH‐TK bionanocomposites thus synthesized was proven to allow easy use and storage of the supported TK with no significant loss of activity over a three‐month period. The kinetic parameters of the LDH‐TK enzyme were comparable to those of the free TK. The LDH‐TK enzyme was finally tested for the synthesis of L ‐erythrulose starting from hydroxypyruvate lithium salt (Li‐HPA) and glycolaldehyde (GA) as substrates. L ‐erythrulose was characterized and obtained with an isolated yield of 56% similar to that obtained with free TK. The reusability of the LDH‐TK biohybrid material was then investigated, and we found no loss of enzymatic activity over six cycles. 相似文献
107.
Tata A Fernandes AM Santos VG Alberici RM Araldi D Parada CA Braguini W Veronez L Silva Bisson G Reis FH Alberici LC Eberlin MN 《Analytical chemistry》2012,84(15):6341-6345
The ability of nanoassisted laser desorption-ionization mass spectrometry (NALDI-MS) imaging to provide selective chemical monitoring with proper spatial distribution of lipid profiles from tumor tissues after plate imprinting has been tested. NALDI-MS imaging identified and mapped several potential lipid biomarkers in a murine model of melanoma tumor (inoculation of B16/F10 cells). It also confirmed that the in vivo treatment of tumor bearing mice with synthetic supplement containing phosphoethanolamine (PHO-S) promoted an accentuated decrease in relative abundance of the tumor biomarkers. NALDI-MS imaging is a matrix-free LDI protocol based on the selective imprinting of lipids in the NALDI plate followed by the removal of the tissue. It therefore provides good quality and selective chemical images with preservation of spatial distribution and less interference from tissue material. The test case described herein illustrates the potential of chemically selective NALDI-MS imaging for biomarker discovery. 相似文献
108.
Jason Stafford Ed Walsh Vanessa Egan 《International Journal of Heat and Mass Transfer》2012,55(7-8):1970-1985
Centrifugal fans are often integrated into thermal management solutions for a range of applications. Consequently, centrifugal fan designs can be subjected to varying environmental conditions, many of which can alter fan performance characteristics and ultimately influence the heat transfer performance of the cooling solution. Global cross flows are a commonly encountered practical operating condition, particularly in the cooling of electronics. Air-cooled electronic enclosures often incorporate miniature centrifugal fans to maintain reliable component operating temperatures at a local level, while larger system level fans are used to simultaneously control the ambient temperature within the enclosure. This type of operating condition has been investigated by introducing a uniform crossing air flow above a centrifugal fan inlet. Two scaled miniature centrifugal fan designs were selected to fundamentally assess the influence on local velocity field and heat transfer performance. This was achieved experimentally using Particle Image Velocimetry, and a combined infrared and heated-thin-foil technique developed for the accurate measurement of local heat transfer coefficients. the introduction of a crossing air flow above the fan inlet indirectly reduced both the local and global thermal performance of the centrifugal fan, and the resultant distorted inflow shifted the surface heat transfer distribution at the fan outlet from an axisymmetric to asymmetric profile. However, strategic positioning of components relative to a centrifugal fan can maintain the average component heat transfer coefficient at a similar level to a case without any cross flow. Results also indicate issues associated with the implementation of miniature centrifugal fan designs into crossing air flow environments, with reductions in thermal performance of over 30% observed. 相似文献
109.
Tatiane Vanessa da Silva SantosAuthor Vitae Renata Roland TeixeiraAuthor Vitae Diego Leoni FrancoAuthor Vitae 《Materials science & engineering. C, Materials for biological applications》2012,32(3):530-535
The aim of this study is the development of a novel bioelectrode based on the immobilization of a specific antibody for salivary amylase onto a graphite electrode modified with poly(3-hydroxyphenylacetic) acid. For this purpose, human salivary alpha-amylase was applied to an immunoaffinity-purified anti-alpha-amylase polyclonal antibody. The bioelectrode was incubated with salivary amylase or lysozyme (interfering salivary), and the interaction between the antibody and the enzymes was analyzed through electrochemical impedance spectroscopy. The results indicated the specificity of the bioelectrode to salivary alpha-amylase. Therefore, the combination of the graphite electrode with poly(3-hydroxyphenylacetic acid) appears to be a promising strategy for antigen immobilization and other biological recognition elements, thus presenting the potential for the production of a label-free biochip. 相似文献
110.
Ultrasmall fluorescent silver nanoclusters: Protein adsorption and its effects on cellular responses
Li Shang René M. Dörlich Vanessa Trouillet Michael Bruns G. Ulrich Nienhaus 《Nano Research》2012,5(8):531-542
Ultrasmall silver nanoclusters (AgNCs) are a novel type of fluorescent nanoprobes that have aroused a great deal of interest in recent years. In view of many promising applications in biological research, it is of great importance to explore their behavior in the complex biological environment. In this study, interactions of AgNCs with a model protein, human serum albumin (HSA), have been systematically investigated by using a variety of techniques including absorption spectroscopy, steady-state and time-resolved fluorescence, as well as circular dichroism spectroscopy. The results show that the physicochemical properties of both proteins and AgNCs undergo changes upon their interactions; however, it appears that the overall conformation of HSA remains essentially unaffected in the complex. Binding of HSA to AgNCs was assessed by measuring tryptophan fluorescence quenching of HSA by AgNCs. Furthermore, biological implications of protein adsorption were quantitatively explored by evaluating responses of HeLa cells to AgNC exposure through live-cell fluorescence microscopy and a cytotoxicity test, revealing that protein adsorption has a significant effect on the biological response to AgNC exposure. 相似文献