keyword
MENU ▼
Read by QxMD icon Read
search

Hydrophobicity

keyword
https://www.readbyqxmd.com/read/28637351/tuning-surface-chemistry-of-polyetheretherketone-by-gold-coating-and-plasma-treatment
#1
Zdeňka Novotná, Silvie Rimpelová, Petr Juřík, Martin Veselý, Zdeňka Kolská, Tomáš Hubáček, Jakub Borovec, Václav Švorčík
Polyetheretherketone (PEEK) has good chemical and biomechanical properties that are excellent for biomedical applications. However, PEEK exhibits hydrophobic and other surface characteristics which cause limited cell adhesion. We have investigated the potential of Ar plasma treatment for the formation of a nanostructured PEEK surface in order to enhance cell adhesion. The specific aim of this study was to reveal the effect of the interface of plasma-treated and gold-coated PEEK matrices on adhesion and spreading of mouse embryonic fibroblasts...
December 2017: Nanoscale Research Letters
https://www.readbyqxmd.com/read/28637081/molecular-characterization-of-gluten-hydrolyzing-bacillus-spp-and-their-efficacy-and-biotherapeutic-potential-as-probiotics-using-caco-2-cell-line
#2
B S Rashmi, Gayathri Devaraja
AIM: To isolate and characterize indigenous gluten hydrolyzing bacteria from wheat sourdough and curd samples and further evaluation of their probiotic potentiality. METHODS AND RESULTS: Indigenous gluten hydrolyzing isolates GS 33, GS 143, GS 181 and GS 188 were identified as Bacillus spp. by molecular-typing methods and studied extensively for their functional and probiotic attributes. All the tested isolates could survive at pH 2 and toxicity of 0.3% bile and also exhibited cell-surface hydrophobicity and autoaggregation phenotype...
June 21, 2017: Journal of Applied Microbiology
https://www.readbyqxmd.com/read/28636916/structural-behavior-of-the-peptaibol-harzianin-hk-vi-in-a-dmpc-bilayer-insights-from-md-simulations
#3
Marina Putzu, Sezgin Kara, Sergii Afonin, Stephan L Grage, Andrea Bordessa, Grégory Chaume, Thierry Brigaud, Anne S Ulrich, Tomáš Kubař
Microsecond molecular dynamics simulations of harzianin HK VI (HZ) interacting with a dimyristoylphosphatidylcholine bilayer were performed at the condition of low peptide-to-lipid ratio. Two orientations of HZ molecule in the bilayer were found and characterized. In the orientation perpendicular to the bilayer surface, HZ induces a local thinning of the bilayer. When inserted into the bilayer parallel to its surface, HZ is located nearly completely within the hydrophobic region of the bilayer. A combination of solid-state NMR and circular dichroism experiments found the latter orientation to be dominant...
June 20, 2017: Biophysical Journal
https://www.readbyqxmd.com/read/28636910/prp40-homolog-a-is-a-novel-centrin-target
#4
Adalberto Díaz Casas, Walter J Chazin, Belinda Pastrana-Ríos
Pre-mRNA processing protein 40 (Prp40) is a nuclear protein that has a role in pre-mRNA splicing. Prp40 possesses two leucine-rich nuclear export signals, but little is known about the function of Prp40 in the export process. Another protein that has a role in protein export is centrin, a member of the EF-hand superfamily of Ca(2+)-binding proteins. Prp40 was found to be a centrin target by yeast-two-hybrid screening using both Homo sapiens centrin 2 (Hscen2) and Chlamydomonas reinhardtii centrin (Crcen). We identified a centrin-binding site within H...
June 20, 2017: Biophysical Journal
https://www.readbyqxmd.com/read/28636597/phase-separation-drives-heterochromatin-domain-formation
#5
Amy R Strom, Alexander V Emelyanov, Mustafa Mir, Dmitry V Fyodorov, Xavier Darzacq, Gary H Karpen
Constitutive heterochromatin is an important component of eukaryotic genomes that has essential roles in nuclear architecture, DNA repair and genome stability, and silencing of transposon and gene expression. Heterochromatin is highly enriched for repetitive sequences, and is defined epigenetically by methylation of histone H3 at lysine 9 and recruitment of its binding partner heterochromatin protein 1 (HP1). A prevalent view of heterochromatic silencing is that these and associated factors lead to chromatin compaction, resulting in steric exclusion of regulatory proteins such as RNA polymerase from the underlying DNA...
June 21, 2017: Nature
https://www.readbyqxmd.com/read/28636594/surface-tension-prevails-over-solute-effect-in-organic-influenced-cloud-droplet-activation
#6
Jurgita Ovadnevaite, Andreas Zuend, Ari Laaksonen, Kevin J Sanchez, Greg Roberts, Darius Ceburnis, Stefano Decesari, Matteo Rinaldi, Natasha Hodas, Maria Cristina Facchini, John H Seinfeld, Colin O' Dowd
The spontaneous growth of cloud condensation nuclei (CCN) into cloud droplets under supersaturated water vapour conditions is described by classic Köhler theory. This spontaneous activation of CCN depends on the interplay between the Raoult effect, whereby activation potential increases with decreasing water activity or increasing solute concentration, and the Kelvin effect, whereby activation potential decreases with decreasing droplet size or increases with decreasing surface tension, which is sensitive to surfactants...
June 21, 2017: Nature
https://www.readbyqxmd.com/read/28636400/click-biotinylation-of-plga-template-for-biotin-receptor-oriented-delivery-of-doxorubicin-hydrochloride-in-4t1-cell-induced-breast-cancer
#7
Yuvraj Singh, K K Durga Rao Viswanadham, Arun Kumar Jajoriya, Jayagopal Meher, Kavit Raval, Swati Jaiswal, Jayant Dewangan, H K Bora, Srikanta Kumar Rath, Jawahar Lal, Durga Prasad Mishra, Manish Kumar Chourasia
PLGA was functionalized with PEG and biotin using click chemistry to generate a biotin receptor targeted copolymer (Biotinylated-PEG-PLGA) which in turn was used to fabricate ultrafine nanoparticles (BPNP) of doxorubicin hydrochloride (DOX) for effective delivery in 4T1 cell induced breast cancer. However adequate entrapment of a hydrophilic bioactive like DOX in a hydrophobic polymer system made of PLGA is not usually possible. We therefore modified a conventional W/O/W emulsion method by utilizing ammonium chloride in the external phase to constrain DOX in dissolved polymer phase by supressing its inherent aqueous solubility as per common ion effect...
June 21, 2017: Molecular Pharmaceutics
https://www.readbyqxmd.com/read/28636369/dynamics-of-charged-species-in-ionic-neutral-block-copolymer-and-surfactant-complexes
#8
Jose M Borreguero, Philip A Pincus, Bobby G Sumpter, Monojoy Goswami
Structure-property relationships of ionic block copolymer (BCP) surfactant complexes are critical towards the progress of favorable engineering design of efficient charge transport materials. In this article, molecular dynamics simulations are used to understand the dynamics of charge-neutral BCP and surfactant complexes. The dynamics are examined for two different systems, charged-neutral double hydrophilic and hydrophobic-hydrophilic block copolymers with oppositely charged surfactant moieties. The dynamics of the surfactant head, tails and charges are studied for five different BCP volume fractions...
June 21, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28636349/water-dynamics-from-the-surface-to-the-interior-of-a-supramolecular-nanostructure
#9
Julia H Ortony, Baofu Qiao, Christina J Newcomb, Timothy J Keller, Liam C Palmer, Elad Deiss-Yehiely, Monica Olvera de la Cruz, Songi Han, Samuel I Stupp
Water within and surrounding the structure of a biological system adopts context-specific dynamics that mediate virtually all of the events involved in the inner workings of a cell. These events range from protein folding and molecular recognition to the formation of hierarchical structures. Water dynamics are mediated by the chemistry and geometry of interfaces where water and biomolecules meet. Here we investigate experimentally and computationally the translational dynamics of vicinal water molecules within the volume of a supramolecular peptide nanofiber measuring 6...
June 21, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28636344/ruthenium-complexes-are-ph-activated-metallo-prodrugs-phamps-with-light-triggered-selective-toxicity-toward-cancer-cells
#10
Fengrui Qu, Seungjo Park, Kristina Martinez, Jessica L Gray, Fathima Shazna Thowfeik, John A Lundeen, Ashley E Kuhn, David J Charboneau, Deidra L Gerlach, Molly M Lockart, James A Law, Katherine L Jernigan, Nicole Chambers, Matthias Zeller, Nicholas A Piro, W Scott Kassel, Russell H Schmehl, Jared J Paul, Edward J Merino, Yonghyun Kim, Elizabeth T Papish
Metallo prodrugs that take advantage of the inherent acidity surrounding cancer cells have yet to be developed. We report a new class of pH-activated metallo prodrugs (pHAMPs) that are activated by light- and pH-triggered ligand dissociation. These ruthenium complexes take advantage of a key characteristic of cancer cells and hypoxic solid tumors (acidity) that can be exploited to lessen the side effects of chemotherapy. Five ruthenium complexes of the type [(N,N)2Ru(PL)](2+) were synthesized, fully characterized, and tested for cytotoxicity in cell culture (1A: N,N = 2,2'-bipyridine (bipy) and PL, the photolabile ligand, = 6,6'-dihydroxybipyridine (6,6'-dhbp); 2A: N,N = 1,10-phenanthroline (phen) and PL = 6,6'-dhbp; 3A: N,N = 2,3-dihydro-[1,4]dioxino[2,3-f][1,10]phenanthroline (dop) and PL = 6,6'-dhbp; 4A: N,N = bipy and PL = 4,4'-dimethyl-6,6'-dihydroxybipyridine (dmdhbp); 5A: N,N = 1,10-phenanthroline (phen) and PL = 4,4'-dihydroxybipyridine (4,4'-dhbp)...
June 21, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28636335/a2b-miktoarm-glycopolymer-fibers-and-their-interactions-with-tenocytes
#11
Renjie Liu, Dharmesh Patel, Hazel R C Screen, C Remzi Becer
Electrospun biodegradable membranes have attracted great attention for a range of tissue engineering applications. Among them, poly (ε-caprolactone) (PCL) is one of the most widely used polymers, owing to its well-controlled biocompatibility and biodegradability. However, PCL also has a number of limitations, such as its hydrophobic nature and the lack of functional groups on its side chain, limiting its ability to interact with cells. Herein, we have designed and prepared a series of well-defined A2B-miktoarm copolymers with PCL and glycopolymer segments to address these limitations...
June 21, 2017: Bioconjugate Chemistry
https://www.readbyqxmd.com/read/28636315/fabrication-of-hierarchical-macroporous-biocompatible-scaffolds-by-combining-pickering-high-internal-phase-emulsion-templates-with-three-dimensional-printing
#12
Ting Yang, Yang Hu, Chaoyang Wang, Bernard P Binks
Biocompatible and biodegradable porous scaffolds with adjustable pore structure have aroused increasing interest in bone tissue engineering. Here, we report a facile method to fabricate hierarchical macroporous biocompatible (HmPB) scaffolds by combining Pickering high internal phase emulsion (HIPE) templates with three-dimensional (3D) printing. HmPB scaffolds composed of a polymer matrix of poly(L-lactic acid), PLLA, and poly(ε-caprolactone), PCL, are readily fabricated by solvent evaporation of 3D printed Pickering HIPEs which are stabilized by hydrophobically modified silica nanoparticles (h-SiO2)...
June 21, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28636048/supramolecular-surface-functionalization-via-catechols-for-the-improvement-of-cell-material-interactions
#13
S Spaans, P P K H Fransen, B D Ippel, D F A de Bont, H M Keizer, N A M Bax, C V C Bouten, P Y W Dankers
Optimization of cell-material interactions is crucial for the success of synthetic biomaterials in guiding tissue regeneration. To do so, catechol chemistry is often used to introduce adhesiveness into biomaterials. Here, a supramolecular approach based on ureido-pyrimidinone (UPy) modified polymers is combined with catechol chemistry in order to achieve improved cellular adhesion onto supramolecular biomaterials. UPy-modified hydrophobic polymers with non-cell adhesive properties are developed that can be bioactivated via a modular approach using UPy-modified catechols...
June 21, 2017: Biomaterials Science
https://www.readbyqxmd.com/read/28636041/fluorescence-properties-of-aurone-derivatives-an-experimental-and-theoretical-study-with-some-preliminary-biological-applications
#14
Christian Espinosa-Bustos, Diego Cortés-Arriagada, Marco A Soto-Arriaza, José Robinson-Duggon, Nancy Pizarro, Alan R Cabrera, Denis Fuentealba, Cristian O Salas
In this paper, we explored the fluorescence properties of eight aurone derivatives bearing methoxy groups and bromine atoms as substituents in the benzene rings. All derivatives showed strong solvatochromic absorption and emission properties in solvents of different polarities. Some of them showed high fluorescence quantum yields, which make them potential compounds for sensing applications. The position of the methoxy groups in the benzofuranone moiety and the presence of bromine atoms in the benzene ring had a strong influence on the fluorescence behaviour of the aurones...
June 21, 2017: Photochemical & Photobiological Sciences
https://www.readbyqxmd.com/read/28635291/fractal-model-for-wettability-of-rough-surfaces
#15
Rahul Jain, Ranga Pitchumani
This paper presents a fractal model to describe wettability on multiscale randomly rough surfaces. Hydrophobic or superhydrophobic surfaces produced using processes such as electrodeposition and etching lead to the creation of random roughness at multiple length scales on the surface. This paper considers the description of such surfaces with a fractal asperity model based on the Weierstrass-Mandelbrot (W-M) function, where the fractal parameters are uniquely determined from a power spectrum of the surface...
June 21, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28635267/cytochrome-c-provides-an-electron-funneling-antenna-for-efficient-photocurrent-generation-in-a-reaction-center-biophotocathode
#16
Vincent Morris Friebe, Diego Millo, David Swainsbury, Michael R Jones, Raoul N Frese
The high quantum efficiency of photosynthetic reaction centers make them attractive for bioelectronic and biophoto-voltaic applications. However, much of the native reaction center efficiency is lost in communication between surface bound reaction centers and electrode materials. State of the art biophotoelectrodes utilizing cytochrome c (cyt c) as a biological wiring agent have at best approached 32% retained RC quantum efficiency. However, bottlenecks in cyt c -mediated electron transfer have not been fully elucidated...
June 21, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28635258/mucin-inspired-lubrication-on-hydrophobic-surfaces
#17
Benjamin Tillmann Käsdorf, Florian Weber, Georgia Petrou, Vaibhav Srivastava, Thomas Crouzier, Oliver Lieleg
In the human body, high molecular weight glycoproteins called mucins play a key role in protecting epithelial surfaces against pathogenic attack, controlling the passage of molecules towards the tissue and enabling boundary lubrication with very low friction coefficients. However, neither the molecular mechanisms nor the chemical motifs of those biomacromolecules involved in these fundamental processes are fully understood. Thus, identifying the key features that render biomacromolecules such as mucins outstanding boundary lubricants could set the stage for creating versatile artificial superlubricants...
June 21, 2017: Biomacromolecules
https://www.readbyqxmd.com/read/28635154/chiral-responsive-liquid-quantum-dots
#18
Jin Zhang, Junkai Ma, Fangdan Shi, Demei Tian, Haibing Li
How to convert the weak chiral-interaction into the macroscopic properties of materials remains a huge challenge. Here, this study develops highly fluorescent, selectively chiral-responsive liquid quantum dots (liquid QDs) based on the hydrophobic interaction between the chiral chains and the oleic acid-stabilized QDs, which have been designated as (S)-1810-QDs. The fluorescence spectrum and liquidity of thermal control demonstrate the fluorescence properties and the fluidic behavior of (S)-1810-QDs in the solvent-free state...
June 21, 2017: Advanced Materials
https://www.readbyqxmd.com/read/28634812/semi-industrial-scale-production-of-a-new-yeast-with-probiotic-traits-cryptococcus-sp-ymhs-isolated-from-the-red-sea
#19
Ashraf F El-Baz, Hesham A El-Enshasy, Yousseria M Shetaia, Hoda Mahrous, Nor Zalina Othman, Ahmed E Yousef
A new yeast strain with promising probiotic traits was isolated from the Red Sea water samples. The isolate (YMHS) was subjected to genetic characterization and identified as Cryptococcus sp. Nucleotide sequence analysis of the rRNA gene internal transcribed spacer regions showed 95% sequence similarity between the isolate and Cryptococcus albidus. Cryptococcus sp. YMHS exhibited desirable characteristics of probiotic microorganisms; it has tolerance to low pH in simulated gastric juice, resistance to bile salts, hydrophobic characteristics, broad antimicrobial activity, and in vitro ability to degrade cholesterol...
June 20, 2017: Probiotics and Antimicrobial Proteins
https://www.readbyqxmd.com/read/28634762/rapid-preconcentration-of-viable-bacteria-using-magnetic-ionic-liquids-for-pcr-amplification-and-culture-based-diagnostics
#20
Kevin D Clark, Jeffrey A Purslow, Stephen A Pierson, Omprakash Nacham, Jared L Anderson
In this study, a series of magnetic ionic liquids (MILs) were investigated for the extraction and preconcentration of bacteria from aqueous samples. By dispersing small volumes (e.g., 15 μL) of MIL within an aqueous cell suspension, bacteria were rapidly extracted and isolated using a magnetic field. Of the seven hydrophobic MILs examined, the trihexyl(tetradecyl)phosphonium Ni(II) hexafluoroacetylacetonate ([P66614(+)][Ni(hfacac)3(-)]) MIL exhibited the greatest enrichment of viable Escherichia coli K12 when coupled with microbiological culture as the detection method...
June 20, 2017: Analytical and Bioanalytical Chemistry
keyword
keyword
106804
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"