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Cerebral Cortex (New York, N.Y. : 1991) Oct 2021Recent advances in neuroimaging have augmented numerous findings in the human reasoning process but have yielded varying results. One possibility for this inconsistency... (Meta-Analysis)
Meta-Analysis
Recent advances in neuroimaging have augmented numerous findings in the human reasoning process but have yielded varying results. One possibility for this inconsistency is that reasoning is such an intricate cognitive process, involving attention, memory, executive functions, symbolic processing, and fluid intelligence, whereby various brain regions are inevitably implicated in orchestrating the process. Therefore, researchers have used meta-analyses for a better understanding of neural mechanisms of reasoning. However, previous meta-analysis techniques include weaknesses such as an inadequate representation of the cortical surface's highly folded geometry. Accordingly, we developed a new meta-analysis method called Bayesian meta-analysis of the cortical surface (BMACS). BMACS offers a fast, accurate, and accessible inference of the spatial patterns of cognitive processes from peak brain activations across studies by applying spatial point processes to the cortical surface. Using BMACS, we found that the common pattern of activations from inductive and deductive reasoning was colocalized with the multiple-demand system, indicating that reasoning is a high-level convergence of complex cognitive processes. We hope surface-based meta-analysis will be facilitated by BMACS, bringing more profound knowledge of various cognitive processes.
Topics: Bayes Theorem; Brain; Humans; Magnetic Resonance Imaging; Neuroimaging; Problem Solving
PubMed: 34180523
DOI: 10.1093/cercor/bhab174 -
International Journal of Molecular... Aug 2021Polyetheretherketone (PEEK), due to its excellent mechanical and physico-chemical parameters, is an attractive substitute for hard tissues in orthopedic applications....
Polyetheretherketone (PEEK), due to its excellent mechanical and physico-chemical parameters, is an attractive substitute for hard tissues in orthopedic applications. However, PEEK is hydrophobic and lacks surface-active functional groups promoting cell adhesion. Therefore, the PEEK surface must be modified in order to improve its cytocompatibility. In this work, extreme ultraviolet (EUV) radiation and two low-temperature, EUV induced, oxygen and nitrogen plasmas were used for surface modification of polyetheretherketone. Polymer samples were irradiated with 100, 150, and 200 pulses at a 10 Hz repetition rate. The physical and chemical properties of EUV and plasma modified PEEK surfaces, such as changes of the surface topography, chemical composition, and wettability, were examined using atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and goniometry. The human osteoblast-like MG63 cells were used for the analysis of cell viability and cell adhesion on all modified PEEK surfaces. EUV radiation and two types of plasma treatment led to significant changes in surface topography of PEEK, increasing surface roughness and formation of conical structures. Additionally, significant changes in the chemical composition were found and were manifested with the appearance of new functional groups, incorporation of nitrogen atoms up to ~12.3 at.% (when modified in the presence of nitrogen), and doubling the oxygen content up to ~25.7 at.% (when modified in the presence of oxygen), compared to non-modified PEEK. All chemically and physically changed surfaces demonstrated cyto-compatible and non-cytotoxic properties, an enhancement of MG63 cell adhesion was also observed.
Topics: Benzophenones; Biocompatible Materials; Cell Adhesion; Cell Line; Humans; Nitrogen; Osteoblasts; Oxygen; Plasma Gases; Polymers; Surface Properties; Ultraviolet Rays
PubMed: 34445159
DOI: 10.3390/ijms22168455 -
Science and Technology of Advanced... Oct 2015Due to their excellent biodegradability characteristics, Mg and Mg-based alloys have become an emerging material in biomedical implants, notably for repair of bone as... (Review)
Review
Due to their excellent biodegradability characteristics, Mg and Mg-based alloys have become an emerging material in biomedical implants, notably for repair of bone as well as coronary arterial stents. However, the main problem with Mg-based alloys is their rapid corrosion in aggressive environments such as human bodily fluids. Previously, many approaches such as control of alloying materials, composition and surface treatments, have been attempted to regulate the corrosion rate. This article presents a comprehensive review of recent research focusing on surface treatment techniques utilised to control the corrosion rate and surface integrity of Mg-based alloys in both and environments. Surface treatments generally involve the controlled deposition of thin film coatings using various coating processes, and mechanical surfacing such as machining, deep rolling or low plasticity burnishing. The aim is to either make a protective thin layer of a material or to change the micro-structure and mechanical properties at the surface and sub-surface levels, which will prevent rapid corrosion and thus delay the degradation of the alloys. We have organised the review of past works on coatings by categorising the coatings into two classes-conversion and deposition coatings-while works on mechanical treatments are reviewed based on the tool-based processes which affect the sub-surface microstructure and mechanical properties of the material. Various types of coatings and their processing techniques under two classes of coating and mechanical treatment approaches have been analysed and discussed to investigate their impact on the corrosion performance, biomechanical integrity, biocompatibility and cell viability. Potential challenges and future directions in designing and developing the improved biodegradable Mg/Mg-based alloy implants were addressed and discussed. The literature reveals that no solutions are yet complete and hence new and innovative approaches are required to leverage the benefit of Mg-based alloys. Hybrid treatments combining innovative biomimetic coating and mechanical processing would be regarded as a potentially promising way to tackle the corrosion problem. Synergetic cutting-burnishing integrated with cryogenic cooling may be another encouraging approach in this regard. More studies focusing on rigorous testing, evaluation and characterisation are needed to assess the efficacy of the methods.
PubMed: 27877829
DOI: 10.1088/1468-6996/16/5/053501 -
Postepy Higieny I Medycyny... Apr 2013Lactobacillus, a genus of Gram-positive bacteria, includes many strains of probiotic microflora. Probiotics, by definition, are living microorganisms that exert... (Review)
Review
Lactobacillus, a genus of Gram-positive bacteria, includes many strains of probiotic microflora. Probiotics, by definition, are living microorganisms that exert beneficial effects on the host organism. The morphology and physiology of the Lactobacillus bacterial genus are described. The structure of the cell wall of Gram-positive bacteria is discussed. The surface S-layer of Lactobacillus composed of proteins (SLP) with low molecular mass is presented. Cell surface proteins participating in the regulation of growth and survival of the intestinal epithelium cells are characterized. The influence of stress factors such as increased temperature, pH, and enzymes of gastric and pancreatic juice on SLP expression is described. The ability of binding of heavy metal ions by S-layer proteins is discussed. The characteristics of these structures, including the ability to adhere to epithelial cells, and the inhibition of invasion of pathogenic microflora of type Shigella, Salmonella, Escherichia coli and Clostridium and their toxins, are presented.
Topics: Bacterial Adhesion; Bacterial Proteins; Cell Wall; Epithelial Cells; Intestinal Mucosa; Lactobacillus; Membrane Glycoproteins
PubMed: 23619222
DOI: 10.5604/17322693.1043393 -
PloS One 2022The wettability of a polymer surface plays a critical role in cell-cell interaction and behavior. The degree to which a surface is hydrophobic or hydrophilic affects the...
The wettability of a polymer surface plays a critical role in cell-cell interaction and behavior. The degree to which a surface is hydrophobic or hydrophilic affects the adhesion and behavior of cells. Two distinct techniques for patterning the surface wettability of a Cyclic Olefin Copolymer (COC) substrate were developed and investigated in this article for the purpose of patterning cell growth. These include oxygen plasma treatment and graphene oxide (GO) coating to alter the wettability of the COC substrate and create hydrophilic patterned regions on a hydrophobic surface. When the two techniques are compared, patterning the surface of COC using GO film results in a more stable wettability over time and increases the roughness of the patterned area. Interestingly, both developed techniques were effective at patterning the COC surface's wettability, which modulated cell adhesion and resulted in micropatterning of cell growth. The novel methods described herein can be used in the fields of cell and tissue culture as well as in the development of new biological assays.
Topics: Graphite; Hydrophobic and Hydrophilic Interactions; Polymers; Surface Properties; Wettability
PubMed: 35709175
DOI: 10.1371/journal.pone.0269914 -
Clinical and Experimental Immunology Jul 1994In this paper we review different aspects of B cell development on the path from the proB cell to the memory B cell and the plasmocyte. Emphasis is given to the positive... (Review)
Review
In this paper we review different aspects of B cell development on the path from the proB cell to the memory B cell and the plasmocyte. Emphasis is given to the positive and negative selection effects mediated by the changing forms of the surface immunoglobulin (Ig) receptor under successive microenvironments. Positive selection is linked to lambda chain expression at the pro- and preB cell stage in fetal liver and bone marrow. Negative selection takes place when surface (s)IgM is being cross-linked by autoantigens before the immature B cell can leave, or after it has left, the bone marrow. After somatic mutation, major expansion becomes possible for B cells with high-affinity sIg receptors. This takes place in the germinal centres of the secondary lymphoid organs in the context of major histocompatibility complex (MHC) restriction and provided the necessary T cell help is given. Kinetic data on B cell replenishment in the rodent models are used to draw a schematic view of an established B cell repertoire.
Topics: Animals; B-Lymphocytes; Bone Marrow; Bone Marrow Cells; Cell Differentiation; Cell Movement; Cellular Senescence; Fetus; Immunoglobulins; Immunologic Memory; Liver; Mice; Models, Biological; Plasma Cells
PubMed: 8033431
DOI: No ID Found -
Microorganisms Feb 2023, a nosocomial pathogen, is an emerging gut pathobiont causing antibiotic-associated diarrhea. infection involves gut colonization and disruption of the gut epithelial... (Review)
Review
, a nosocomial pathogen, is an emerging gut pathobiont causing antibiotic-associated diarrhea. infection involves gut colonization and disruption of the gut epithelial barrier, leading to the induction of inflammatory/immune responses. The expression of two major exotoxins, TcdA and TcdB is the major cause of pathogenicity. Attachment of bacterial abundant cell wall proteins or surface S-layer proteins (SLPs) such as SlpA with host epithelial cells is critical for virulence. In addition to being toxins, these surface components have been shown to be highly immunogenic. Recent studies indicate that SLPs play important roles in the adhesion of the bacteria to the intestinal epithelial cells, disruption of tight junctions, and modulation of the immune response of the host cells. These proteins might serve as new targets for vaccines and new therapeutic agents. This review summarizes our current understanding of the immunological role of SLPs in inducing host immunity and their use in the development of vaccines and novel therapeutics to combat infection.
PubMed: 36838345
DOI: 10.3390/microorganisms11020380 -
International Journal of Molecular... Dec 2014Many crop plants are exposed to heavy metals and other metals that may intoxicate the crop plants themselves or consumers of the plants. The rhizotoxicity of heavy... (Review)
Review
Many crop plants are exposed to heavy metals and other metals that may intoxicate the crop plants themselves or consumers of the plants. The rhizotoxicity of heavy metals is influenced strongly by the root cell plasma membrane (PM) surface's electrical potential (ψ). The usually negative ψ is created by negatively charged constituents of the PM. Cations in the rooting medium are attracted to the PM surface and anions are repelled. Addition of ameliorating cations (e.g., Ca2+ and Mg2+) to the rooting medium reduces the effectiveness of cationic toxicants (e.g., Cu2+ and Pb2+) and increases the effectiveness of anionic toxicants (e.g., SeO2- and HAsO-). Root growth responses to ions are better correlated with ion activities at PM surfaces ({IZ}) than with activities in the bulk-phase medium ({IZ}) (IZ denotes an ion with charge Z). Therefore, electrostatic effects play a role in heavy metal toxicity that may exceed the role of site-specific competition between toxicants and ameliorants. Furthermore, ψ controls the transport of ions across the PM by influencing both {IZ} and the electrical potential difference across the PM from the outer surface to the inner surface (E). E is a component of the driving force for ion fluxes across the PM and controls ion-channel voltage gating. Incorporation of {IZ} and E into quantitative models for root metal toxicity and uptake improves risk assessments of toxic metals in the environment. These risk assessments will improve further with future research on the application of electrostatic theory to heavy metal phytotoxicity in natural soils and aquatic environments.
PubMed: 25493475
DOI: 10.3390/ijms151222661 -
Developmental Cell Oct 2023Proper localization of receptors for synaptic organizing factors is crucial for synapse formation. Wnt proteins promote synapse assembly through Frizzled (Fz) receptors....
Proper localization of receptors for synaptic organizing factors is crucial for synapse formation. Wnt proteins promote synapse assembly through Frizzled (Fz) receptors. In hippocampal neurons, the surface and synaptic localization of Fz5 is regulated by neuronal activity, but the mechanisms involved remain poorly understood. Here, we report that all Fz receptors can be post-translationally modified by S-acylation and that Fz5 is S-acylated on three C-terminal cysteines by zDHHC5. S-acylation is essential for Fz5 localization to the cell surface, axons, and presynaptic sites. Notably, S-acylation-deficient Fz5 is internalized faster, affecting its association with signalosome components at the cell surface. S-acylation-deficient Fz5 also fails to activate canonical and divergent canonical Wnt pathways. Fz5 S-acylation levels are regulated by the pattern of neuronal activity. In vivo studies demonstrate that S-acylation-deficient Fz5 expression fails to induce presynaptic assembly. Our studies show that S-acylation of Frizzled receptors is a mechanism controlling their localization and function.
Topics: Animals; Rodentia; Frizzled Receptors; Wnt Signaling Pathway; Hippocampus; Acylation
PubMed: 37557176
DOI: 10.1016/j.devcel.2023.07.012 -
Surfaces: a software to quantify and visualize interactions within and between proteins and ligands.Bioinformatics (Oxford, England) Oct 2023Computational methods for the quantification and visualization of the relative contribution of molecular interactions to the stability of biomolecular structures and...
SUMMARY
Computational methods for the quantification and visualization of the relative contribution of molecular interactions to the stability of biomolecular structures and complexes are fundamental to understand, modulate and engineer biological processes. Here, we present Surfaces, an easy to use, fast and customizable software for quantification and visualization of molecular interactions based on the calculation of surface areas in contact. Surfaces calculations shows equivalent or better correlations with experimental data as computationally expensive methods based on molecular dynamics.
AVAILABILITY AND IMPLEMENTATION
All scripts are available at https://github.com/NRGLab/Surfaces. Surface's documentation is available at https://surfaces-tutorial.readthedocs.io/en/latest/index.html.
Topics: Software; Proteins; Molecular Dynamics Simulation; Documentation; Ligands
PubMed: 37788107
DOI: 10.1093/bioinformatics/btad608