Search results for "Biophysic"
showing 10 items of 3565 documents
Dissection of C1q Capability of Interacting with IgG
1997
Abstract C1q-bearing immune complexes have been observed in diseases such as rheumatoid arthritis and human immunodeficiency virus infection-associated neuropathy. For the purpose of understanding better the phenomenon of C1q-bearing immune complexes, we investigated the constancy of the C1q-IgG interaction. An enzyme-linked immunosorbent assay was developed in which wells were coated with IgG to mimic antigen-complexed IgG. Serial dilutions of C1q were applied for distinct time intervals, and bound C1q was detected either directly or after exposure to one of several elution buffers. Our results show that a part of C1q attached to IgG forms a tight association that is not reversible under t…
The vertical spectrum of H2CO revisited: (SC)2-CI and CC calculations
2003
The vertical electronic spectrum of formaldehyde has been studied by means of (SC)2-MR-SDCI and CCLR methods. Two basis sets of atomic natural orbitals (ANOs) complemented with a one-centre series of Rydberg orbitals were used. The first was taken from the CASPT2 study by Merchan, M., and Roos, B. O., 1995, Theoret. Chim. Acta, 92, 221, and may be described as C,O[4s3pld]/H[2slp] with a lslpld Rydberg series centred in the charge centroid of the 2B2 state of the cation. The second was a larger basis set that may be described as C,O[6s5p3d2f]/H[4s3p2d] + 3s3p3d in the same centre. The (SC)2 dressing may be applied efficiently to an MR-SDCI method and comparison with the dressed CAS-SDCI is s…
Isolation and characterization of a fish F-type lectin from gilt head bream (Sparus aurata) serum.
2007
A novel fucose-binding lectin, designated SauFBP32, was purified by affinity chromatography on fucose-agarose, from the serum of the gilt head bream Sparus aurata. Electrophoretic mobility of the subunit revealed apparent molecular weights of 35 and 30 kDa under reducing and non-reducing conditions, respectively. Size exclusion analysis suggests that the native lectin is a monomer under the selected experimental conditions. Agglutinating activity towards rabbit erythrocytes was not significantly modified by addition of calcium or EDTA; activity was optimal at 37 degrees C, retained partial activity by treatment at 70 degrees C, and was fully inactivated at 90 degrees C. On western blot anal…
Bioactive glass ions induce efficient osteogenic differentiation of human adipose stem cells encapsulated in gellan gum and collagen type I hydrogels
2019
Abstract Background Due to unmet need for bone augmentation, our aim was to promote osteogenic differentiation of human adipose stem cells (hASCs) encapsulated in gellan gum (GG) or collagen type I (COL) hydrogels with bioactive glass (experimental glass 2-06 of composition [wt-%]: Na2O 12.1, K2O 14.0, CaO 19.8, P2O5 2.5, B2O3 1.6, SiO2 50.0) extract based osteogenic medium (BaG OM) for bone construct development. GG hydrogels were crosslinked with spermidine (GG-SPD) or BaG extract (GG-BaG). Methods Mechanical properties of cell-free GG-SPD, GG-BaG, and COL hydrogels were tested in osteogenic medium (OM) or BaG OM at 0, 14, and 21 d. Hydrogel embedded hASCs were cultured in OM or BaG OM fo…
A serum fucolectin isolated and characterized from sea bass Dicentrarchus labrax
2001
A lectin specific for fucose and galactose was isolated by affinity chromatography on Sepharose CL-6B from the serum of Dicentrarchus labrax. The hemagglutinating activity against rabbit erythrocytes was calcium-independent, and reached its maximum at 37 degrees C. Two protein components were found in the hemagglutinating fractions eluted from the Sepharose column. Only the 34 kDa component (DLL2) eluted from the polyacrylamide gels (SDS-PAGE) showed agglutinating activity against rabbit erythrocytes. SDS-PAGE, in non-reducing conditions, revealed a single 66 kDa protein that reacted with antibodies to the 34 kDa component. Therefore, a dimeric structure stabilized by disulfide bonds can be…
Aggregation behavior of cationic nanohydrogel particles in human blood serum.
2014
For systemic siRNA delivery applications, well-defined drug carriers are required that guarantee stability for both carrier and cargo. Among various concepts progressing in market or final development, cationic nanohydrogel particles may serve as novel transport media especially designed for siRNA-in vivo experiments. In this work, the interaction of nanohydrogel particles with proteins and serum components was studied via dynamic light scattering in human blood serum as novel screening method prior to applications in vivo. The formation of larger aggregates mostly caused by charge interaction with albumin could be suppressed by nanogel loading with siRNA affording a neutral zeta potential …
A bioenergetics framework for integrating the effects of multiple stressors: Opening a 'black box' in climate change research
2015
Climate change is already impacting marine ecosystems across a range of scales, from individual physiology, to changes in species interactions and community structure, and ultimately to patterns in geographic distribution. Predicting how marine ecosystems will respond to environmental change is a signifi cant challenge because vulnerability to climatic and non-climatic stressors is highly variable, and depends on an organism’s functional traits, tolerance to stressors, and the environment in which it lives. We present a mechanistic approach based on biophysical and dynamic energy budget models that integrates the cumulative effects of multiple environmental stressors (temperature and food) …
The effect of time-of-day and sleep deprivation on postural control: A systematic review.
2022
Background: Postural control (PC) can be affected by circadian rhythm and sleep deprivation, whereby it has been reported the result of PC measurement in clinical and experimental situations can be influenced by both factors. It has been suggested sleepiness can result in deficiency in PC, which in turn can lead to occupational accidents and subsequent injuries. This is while no study critically reviews or summarizes findings surrounding this topic in the literature. Research question: Is there any significant effect of sleep deprivation and circadian rhythm on PC variables among healthy individuals? Methods: PubMed, Web of Science, Scopus, and Embase were used to detect relevant studies. O…
Techniques to evaluate erythrocyte deformability in diabetes mellitus
2005
Using several rheological techniques, we examined the erythrocyte deformability in different groups of diabetic subjects. The macrorheological techniques used for this evaluation were respectively whole-blood filtration, filtration of erythrocyte suspensions, polyviscosimetry and diffractometry. Whole-blood filterability, at a negative pressure of 20 cm water, was decreased in type 2 diabetics; no difference was evident at a negative pressure of 10 cm water. The filtration of erythrocyte suspensions at low haematocrit (5%) did not show differences between normal and diabetic subjects. The polyviscosimetry, which explores the filterability of erythrocyte suspensions at high haematocrit (80%)…
Electron transfer mechanism in Shewanella loihica PV-4 biofilms formed at graphite electrode
2012
Abstract Electron transfer mechanisms in Shewanella loihica PV-4 viable biofilms formed at graphite electrodes were investigated in potentiostat-controlled electrochemical cells poised at oxidative potentials (0.2 V vs. Ag/AgCl). Chronoamperometry (CA) showed a repeatable biofilm growth of S. loihica PV-4 on graphite electrode. CA, cyclic voltammetry (CV) and its first derivative shows that both direct electron transfer (DET) mediated electron transfer (MET) mechanism contributes to the overall anodic (oxidation) current. The maximum anodic current density recorded on graphite was 90 μA cm − 2 . Fluorescence emission spectra shows increased concentration of quinone derivatives and riboflavi…