A Key Major Guideline for Engineering Bioactive Multicomponent Nanofunctionalization for Biomedicine and Other Applications: Fundamental Models Confirmed by Both Direct and Indirect Evidence

This paper deals with the engineering multicomponent nanofunctionalization process considering fundamental physicochemical features of nanostructures such as surface energy, chemical bonds, and electrostatic interactions. It is pursued by modeling the surface nanopatterning and evaluating the proposed technique and the models. To this end, the effects of surface modifications of nanoclay on surface interactions, orientations, and final features of TiO2/Mt nanocolloidal textiles functionalization have been investigated. Various properties of cross-linkable polysiloxanes (XPs) treated samples as well as untreated samples with XPs have been compared to one another. The complete series of samples have been examined in terms of bioactivity and some physical properties, given to provide indirect evidence on the surface nanopatterning. The results disclosed a key role of the selected factors on the final features of treated surfaces. The effects have been thoroughly explained and modeled according to the fundamental physicochemical features. The developed models and associated hypotheses interestingly demonstrated a full agreement with all measured properties and were appreciably confirmed by FESEM evidence (direct evidence). Accordingly, a guideline has been developed to facilitate engineering and optimizing the pre-, main, and post-multicomponent nanofunctionalization procedures in terms of fundamental features of nanostructures and substrates for biomedical applications and other approaches.

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Structural Transformations and Their Precursors

Australian Journal of Physics ◽

10.1071/ph830553 ◽

1983 ◽

Vol 36 (4) ◽

pp. 553 ◽

Cited By ~ 9

Author(s):

TR Finlayson

Keyword(s):

Thermal Expansion ◽

Electron Diffraction ◽

Physical Properties ◽

Elastic Constants ◽

Direct Evidence ◽

Indirect Evidence ◽

Structural Transformations ◽

X Ray ◽

Kinetics Of

For a number of materials which exhibit a change of structure on being cooled below a certain temperature Tm, some physical properties display anomalous behaviour at temperatures above Tm. The particular structural transformations in mind have been broadly classified as 'martensitic' and the anomalous physical properties as 'precursive phenomena'. Some debate exists regarding the role of the precursive phenomenon in the kinetics of the structural transformation. The most direct evidence for 'martensite precursors' is obtained from electron diffraction, although various indirect evidence is contained in X-ray, neutron and y-ray diffraction and various physical properties, for example, elastic constants and thermal expansion. In this paper current understanding of 'martensite precursors' is reviewed and examples of data from the A15 structure compounds V 3Si and Nb3Sn,. In-TI and TiNi alloys are discussed.

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Direct Evidence for the Role of Inhibition in Resolving Interference

PsycEXTRA Dataset ◽

10.1037/e636632009-001 ◽

2009 ◽

Author(s):

M. Karl Healey ◽

Karen L. Campbell ◽

Lynn Hasher ◽

Lynn Ossher

Keyword(s):

Direct Evidence

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CHOP-Dependent Stress-Inducible Expression of a Novel Form of Carbonic Anhydrase VI

Molecular and Cellular Biology ◽

10.1128/mcb.19.1.495 ◽

1999 ◽

Vol 19 (1) ◽

pp. 495-504 ◽

Cited By ~ 102

Author(s):

John Sok ◽

Xiao-Zhong Wang ◽

Nikoleta Batchvarova ◽

Masahiko Kuroda ◽

Heather Harding ◽

...

Keyword(s):

Carbonic Anhydrase ◽

Target Gene ◽

Target Genes ◽

Direct Evidence ◽

Nuclear Protein ◽

Intracellular Form ◽

Carbonic Anhydrase Vi ◽

Responsive Element

ABSTRACT CHOP (also called GADD153) is a stress-inducible nuclear protein that dimerizes with members of the C/EBP family of transcription factors and was initially identified as an inhibitor of C/EBP binding to classic C/EBP target genes. Subsequent experiments suggested a role for CHOP-C/EBP heterodimers in positively regulating gene expression; however, direct evidence that this is the case has so far not been uncovered. Here we describe the identification of a positively regulated direct CHOP-C/EBP target gene, that encoding murine carbonic anhydrase VI (CA-VI). The stress-inducible form of the gene is expressed from an internal promoter and encodes a novel intracellular form of what is normally a secreted protein. Stress-induced expression of CA-VI is both CHOP and C/EBPβ dependent in that it does not occur in cells deficient in either gene. A CHOP-responsive element was mapped to the inducibleCA-VI promoter, and in vitro footprinting revealed binding of CHOP-C/EBP heterodimers to that site. Rescue of CA-VIexpression in c/ebpβ−/− cells by exogenous C/EBPβ and a shorter, normally inhibitory isoform of the protein known as LIP suggests that the role of the C/EBP partner is limited to targeting the CHOP-containing heterodimer to the response element and points to a preeminent role for CHOP in CA-VI induction during stress.

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Electrostatic interactions in cytochrome c. The role of interactions between residues 13 and 90 and residues 79 and 47 in stabilizing the heme crevice structure.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)86087-8 ◽

1980 ◽

Vol 255 (4) ◽

pp. 1689-1697

Author(s):

N. Osheroff ◽

D. Borden ◽

W.H. Koppenol ◽

E. Margoliash

Keyword(s):

Cytochrome C ◽

Electrostatic Interactions

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Protein and Polysaccharide-Based Electroactive and Conductive Materials for Biomedical Applications

Molecules ◽

10.3390/molecules26154499 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4499

Author(s):

Xiao Hu ◽

Samuel Ricci ◽

Sebastian Naranjo ◽

Zachary Hill ◽

Peter Gawason

Keyword(s):

Cell Biology ◽

Biomedical Applications ◽

Human Life ◽

Electrically Conductive ◽

Conductive Materials ◽

Production Strategies ◽

Integral Role ◽

Material Sciences ◽

Novel Drug

Electrically responsive biomaterials are an important and emerging technology in the fields of biomedical and material sciences. A great deal of research explores the integral role of electrical conduction in normal and diseased cell biology, and material scientists are focusing an even greater amount of attention on natural and hybrid materials as sources of biomaterials which can mimic the properties of cells. This review establishes a summary of those efforts for the latter group, detailing the current materials, theories, methods, and applications of electrically conductive biomaterials fabricated from protein polymers and polysaccharides. These materials can be used to improve human life through novel drug delivery, tissue regeneration, and biosensing technologies. The immediate goal of this review is to establish fabrication methods for protein and polysaccharide-based materials that are biocompatible and feature modular electrical properties. Ideally, these materials will be inexpensive to make with salable production strategies, in addition to being both renewable and biocompatible.

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Effect of tungsten disulfide nanotubes on crystallization of polylactide under uniaxial deformation and annealing

Functional Composite Materials ◽

10.1186/s42252-021-00016-2 ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Fausta Loffredo ◽

Loredana Tammaro ◽

Tiziana Di Luccio ◽

Carmela Borriello ◽

Fulvia Villani ◽

...

Keyword(s):

Biomedical Applications ◽

Structural Evolution ◽

Tungsten Disulfide ◽

Fine Tuning ◽

Nanocomposite Films ◽

Uniaxial Deformation ◽

Scanning Calorimetry ◽

X Ray ◽

X Ray Scattering

AbstractTungsten disulfide (WS2) nanotubes (NTs) are examined here as a filler for polylactide (PLA) for their ability to accelerate PLA crystallization and for their promising biocompatibility in relevant to biomedical applications of PLA-WS2 nanocomposites. In this work, we have studied the structural and thermal properties of PLA-WS2 nanocomposite films varying the concentration of WS2 NTs from 0 (neat PLA) to 0.6 wt%. The films were uniaxially drawn at 90 °C and annealed at the same temperature for 3 and 10 min. Using wide angle x-ray scattering, Raman spectroscopy and differential scanning calorimetry, we probed the effects of WS2 NT addition on the structure of the PLA films at various stages of processing (unstretched, stretching, annealing). We found that 0.6 wt% of WS2 induces the same level of crystallinity in as stretched PLA-WS2 as annealing in neat PLA for 10 min. These data provide useful insights into the role of WS2 NTs on the structural evolution of PLA-WS2 composites under uniaxial deformation, and extend their applicability to situations where fine tuning of PLA crystallinity is desirable.

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Stoichiometric Analysis of Shifting in Subcellular Compartmentalization of HSP70 within Ischemic Penumbra

Molecules ◽

10.3390/molecules26123578 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3578

Author(s):

Federica Mastroiacovo ◽

Francesca Biagioni ◽

Paola Lenzi ◽

Larisa Ryskalin ◽

Stefano Puglisi-Allegra ◽

...

Keyword(s):

Direct Evidence ◽

Neuronal Survival ◽

Hsp 70 ◽

Preclinical Models ◽

Brain Areas ◽

Cell Compartments ◽

Control Brain ◽

Disease Modifier ◽

Subcellular Compartmentalization

The heat shock protein (HSP) 70 is considered the main hallmark in preclinical studies to stain the peri-infarct region defined area penumbra in preclinical models of brain ischemia. This protein is also considered as a potential disease modifier, which may improve the outcome of ischemic damage. In fact, the molecule HSP70 acts as a chaperonine being able to impact at several level the homeostasis of neurons. Despite being used routinely to stain area penumbra in light microscopy, the subcellular placement of this protein within area penumbra neurons, to our knowledge, remains undefined. This is key mostly when considering studies aimed at deciphering the functional role of this protein as a determinant of neuronal survival. The general subcellular placement of HSP70 was grossly reported in studies using confocal microscopy, although no direct visualization of this molecule at electron microscopy was carried out. The present study aims to provide a direct evidence of HSP70 within various subcellular compartments. In detail, by using ultrastructural morphometry to quantify HSP70 stoichiometrically detected by immuno-gold within specific organelles we could compare the compartmentalization of the molecule within area penumbra compared with control brain areas. The study indicates that two cell compartments in control conditions own a high density of HSP70, cytosolic vacuoles and mitochondria. In these organelles, HSP70 is present in amount exceeding several-fold the presence in the cytosol. Remarkably, within area penumbra a loss of such a specific polarization is documented. This leads to the depletion of HSP70 from mitochondria and mostly cell vacuoles. Such an effect is expected to lead to significant variations in the ability of HSP70 to exert its physiological roles. The present findings, beyond defining the neuronal compartmentalization of HSP70 within area penumbra may lead to a better comprehension of its beneficial/detrimental role in promoting neuronal survival.

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Current Research on Polyelectrolyte Nanostructures: From Molecular Interactions to Biomedical Applications

Macromol ◽

10.3390/macromol1020012 ◽

2021 ◽

Vol 1 (2) ◽

pp. 155-172

Author(s):

Aristeidis Papagiannopoulos

Keyword(s):

Physical Properties ◽

Molecular Interactions ◽

Interdisciplinary Research ◽

Biomedical Applications ◽

Electrostatic Interactions ◽

Soft Matter ◽

Extracellular Polysaccharides ◽

Polymer Science ◽

Biological Matter ◽

Biomedical Field

Polyelectrolytes have been at the center of interdisciplinary research for many decades. In the field of polymer science and soft matter, they have provided the dimensions of electrostatic interactions, which opens a vast variety of opportunities for new physical properties and applications. In biological matter, polyelectrolytes are present in many forms, from extracellular polysaccharides to complex DNA molecules and proteins. This review discusses the recent research on polyelectrolytes covering the fundamental level of their conformations and nanostructures, their molecular interactions with materials that have close relevance to bioapplications and their applications in the biomedical field. This approach is motivated by the fact that the polyelectrolyte research is constantly active in all the aforementioned levels and continually affects many critical scientific areas.

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