Structural Alternation in Heat Shock Proteins of Activated Macrophages

The inflammatory response of macrophages is an orderly and complex process under strict regulation accompanied by drastic changes in morphology and functions. It is predicted that proteins will undergo structural changes during these finely regulated processes. However, changes in structural proteome in macrophages during the inflammatory response remain poorly characterized. In the present study, we applied limited proteolysis coupled mass spectrometry (LiP-MS) to identify proteome-wide structural changes in lipopolysaccharide (LPS)-activated macrophages. We identified 386 structure-specific proteolytic fingerprints from 230 proteins. Using the Gene Ontology (GO) biological process enrichment, we discovered that proteins with altered structures were enriched into protein folding-related terms, in which HSP60 was ranked as the most changed protein. We verified the structural changes in HSP60 by using cellular thermal shift assay (CETSA) and native CETSA. Our results showed that the thermal stability of HSP60 was enhanced in activated macrophages and formed an HSP10-less complex. In conclusion, we demonstrate that in situ structural systems biology is an effective method to characterize proteomic structural changes and reveal that the structures of chaperone proteins vary significantly during macrophage activation.

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Study of the structural degradation of steel 15Kh5M upon continuous duty

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2020-86-1-38-43 ◽

2020 ◽

Vol 86 (1) ◽

pp. 38-43

Author(s):

Vladimir A. Kim ◽

Valeriya V. Lysenko ◽

Anna A. Afanaseva ◽

Khasan I. Turkmenov

Keyword(s):

Grain Boundaries ◽

Structural Changes ◽

Structural Transformations ◽

Structural Degradation ◽

Structural Arrangement ◽

Dispersed Particles ◽

Complex Process ◽

Multifractal Spectra ◽

Steel 15Kh5m ◽

Complex Indicators

Structural degradation of the material upon long-term thermal and force impacts is a complex process which includes migration of the grain boundaries, diffusion of the active elements of the external and technological environment, hydrogen embrittlement, aging, grain boundary corrosion and other mechanisms. Application of the fractal and multifractal formalism to the description of microstructures opens up wide opportunities for quantitative assessment of the structural arrangement of the material, clarifies and reveals new aspects of the known mechanisms of structural transformations. Multifractal parameterization allows us to study the processes of structural degradation from the images of microstructures and identify structural changes that are hardly distinguishable visually. Any quantitative structural indicator can be used to calculate the multifractal spectra of the microstructure, but the most preferable is that provides the maximum range of variation in the numerical values of the multifractal components. The results of studying structural degradation of steel 15Kh5M upon continuous duty are presented. It is shown that structural degradation of steel during operation under high temperatures and stresses is accompanied by enlargement of the microstructural objects, broadening of the grain boundaries and allocation of the dispersed particles which are represented as point objects in the images. The processes of structural degradation lead to an increase in the range of changes in the components of the multifractal spectra. High values of complex indicators of structural arrangement indicate to an increase in heterogeneity and randomness at the micro-scale level, but at the same time, to manifestation of the ordered combinations of individual submicrostructures. Those structural transformations adapt the material to external impacts and provide the highest reliability and fracture resistance of the material.

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Roughened gold electrode for in situ SERS analysis of structural changes accompanying the doping process of polyaniline in acidic aqueous media

Journal of Electroanalytical Chemistry ◽

10.1016/j.jelechem.2021.115034 ◽

2021 ◽

Vol 882 ◽

pp. 115034

Author(s):

A. El Guerraf ◽

M. Bouabdallaoui ◽

Z. Aouzal ◽

S. Ben Jadi ◽

N.K. Bakirhan ◽

...

Keyword(s):

Gold Electrode ◽

Structural Changes ◽

Aqueous Media

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ER Stress, UPR Activation and the Inflammatory Response to Viral Infection

Viruses ◽

10.3390/v13050798 ◽

2021 ◽

Vol 13 (5) ◽

pp. 798

Author(s):

Mara Cirone

Keyword(s):

Inflammatory Response ◽

Viral Infection ◽

Viral Infections ◽

Protective Role ◽

Microbial Infection ◽

Unfolded Protein ◽

Cytokines And Chemokines ◽

Complex Process ◽

Protein Response ◽

Recognition Receptor

The response to invading pathogens such as viruses is orchestrated by pattern recognition receptor (PRR) and unfolded protein response (UPR) signaling, which intersects and converges in the activation of proinflammatory pathways and the release of cytokines and chemokines that harness the immune system in the attempt to clear microbial infection. Despite this protective intent, the inflammatory response, particularly during viral infection, may be too intense or last for too long, whereby it becomes the cause of organ or systemic diseases itself. This suggests that a better understanding of the mechanisms that regulate this complex process is needed in order to achieve better control of the side effects that inflammation may cause while potentiating its protective role. The use of specific inhibitors of the UPR sensors or PRRs or the downstream pathways activated by their signaling could offer the opportunity to reach this goal and improve the outcome of inflammation-based diseases associated with viral infections.

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High temperature structural study of decagonal Al-Cu-Rh quasicrystal.

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314099057 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C94-C94

Author(s):

Pawel Kuczera ◽

Walter Steurer

Keyword(s):

Structural Changes ◽

Configurational Entropy ◽

Lattice Vibrations ◽

X Ray Diffraction ◽

Stabilization Mechanism ◽

X Ray ◽

Comparative Structure ◽

The Stability

The structure of d(ecagonal)-Al-Cu-Rh has been studied as a function of temperature by in-situ single-crystal X-ray diffraction in order to contribute to the discussion on energy or entropy stabilization of quasicrystals (QC) [1]. The experiments were performed at 293 K, 1223 K, 1153 K, 1083 K, and 1013 K. A common subset of 1460 unique reflections was used for the comparative structure refinements at each temperature. The results obtained for the HT structure refinements of d-Al-Cu-Rh QC seem to contradict a pure phasonic-entropy-based stabilization mechanism [2] for this QC. The trends observed for the ln func(I(T1 )/I(T2 )) vs.|k⊥ |^2 plots indicate that the best on-average quasiperiodic order exists between 1083 K and 1153 K, however, what that actually means is unclear. It could indicate towards a small phasonic contribution to entropy, but such contribution is not seen in the structure refinements. A rough estimation of the hypothetic phason instability temperature shows that it would be kinetically inaccessible and thus the phase transition to a 12 Å low T structure (at ~800 K) is most likely not phason-driven. Except for the obvious increase in the amplitude of the thermal motion, no other significant structural changes, in particular no sources of additional phason-related configurational entropy, were found. All structures are refined to very similar R-values, which proves that the quality of the refinement at each temperature is the same. This suggests, that concerning the stability factors, some QCs could be similar to other HT complex intermetallic phases. The experimental results clearly show that at least the ~4 Å structure of d-Al-Cu-Rh is a HT phase therefore entropy plays an important role in its stabilisation mechanism lowering the free energy. However, the main source of this entropy is probably not related to phason flips, but rather to lattice vibrations, occupational disorder unrelated to phason flips like split positions along the periodic axis.

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A qualitative and quantitative method for in situ characterization of the inflammatory response in experimental myocarditis

Apmis ◽

10.1111/j.1699-0463.1990.tb01071.x ◽

1990 ◽

Vol 98 (1-6) ◽

pp. 559-567 ◽

Cited By ~ 12

Author(s):

J. Fohlman ◽

G. Friman ◽

N. G. IlbÄCk ◽

Å. ÅKesson ◽

S. Huber

Keyword(s):

Inflammatory Response ◽

Quantitative Method ◽

In Situ Characterization ◽

Qualitative And Quantitative ◽

Experimental Myocarditis

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In situ forming chitosan hydrogels: Preliminary evaluation of the in vivo inflammatory response

Materials Science and Engineering C ◽

10.1016/j.msec.2017.02.050 ◽

2017 ◽

Vol 75 ◽

pp. 279-285 ◽

Cited By ~ 9

Author(s):

Maria José Moura ◽

João Brochado ◽

Maria Helena Gil ◽

Maria Margarida Figueiredo

Keyword(s):

Inflammatory Response ◽

Preliminary Evaluation ◽

In Situ Forming ◽

Chitosan Hydrogels

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Alterations of band 3 transport protein by cellular aging and disease: erythrocyte band 3 and glucose transporter share a functional relationship

Biochemistry and Cell Biology ◽

10.1139/o90-205 ◽

1990 ◽

Vol 68 (12) ◽

pp. 1419-1427 ◽

Cited By ~ 15

Author(s):

Gieljan J. C. G. M. Bosman ◽

Marguerite M. B. Kay

Keyword(s):

Glucose Transport ◽

Structural Changes ◽

Glucose Transporter ◽

Functional Relationship ◽

Band 3 ◽

Anion Transport ◽

Cellular Aging ◽

Abnormal Band ◽

Membrane Spanning

Structural changes in human erythrocyte band 3 that affect anion transport are correlated with changes in glucose transport in situ. Breakdown of band 3, observed during normal erythrocyte aging in situ and in some diseases involving erythrocytes, is associated with an increase in Km and a decrease in Vmax of sulfate self-exchange, and with an increase in Km and Vmax of glucose efflux. Erythrocytes containing a high molecular weight form of band 3 exhibit an increase in Vmax of sulfate exchange and a decrease in Vmax of glucose efflux. Identical transport characteristics are observed in abnormal band-3-containing erythrocytes from individuals with familial amyotrophic chorea with acanthocytosis. A third band 3 alteration, fast-aging band 3, exhibits decreased Vmax of sulfate exchange and an increase in Km and decrease in Vmax of glucose efflux. Changes in band 3 structure that are the result of unstable hemoglobin or a deficiency in glucose-6-phosphate dehydrogenase and that do not affect anion transport have no effect on glucose transport characteristics. These data indicate the existence of a functional relationship between the membrane-spanning, anion-transport domain of band 3 and glucose transport in human erythrocytes. Antibodies to synthetic peptides reveal structural changes in membranes from the three inborn band 3 alterations and in band 3 itself in membranes from fast-aging band 3. Thus, immunological data suggests a structural relationship between anion and glucose transporters.Key words: red cell, anion transport, membrane proteins, aging, choreoacanthocytosis, anemia.

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The Effect of Bile Salts on the Permeability and Ultrastructure of the Perfused, Energy-Depleted, Rat Blood-Brain Barrier

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1991.116 ◽

1991 ◽

Vol 11 (4) ◽

pp. 644-654 ◽

Cited By ~ 41

Author(s):

J. Greenwood ◽

J. Adu ◽

A. J. Davey ◽

N. J. Abbott ◽

M. W. B. Bradbury

Keyword(s):

Blood Brain Barrier ◽

Bile Salts ◽

Structural Changes ◽

Sodium Deoxycholate ◽

Ringer Solution ◽

Brain Barrier ◽

Rat Blood ◽

Blood Brain ◽

Ultrastructural Damage

The action of bile salts upon the rat blood–brain barrier (BBB) was assessed in the absence of energy-yielding metabolism. Brains were perfused in situ with a Ringer solution for 5 min followed by a 1 min perfusion containing either sodium deoxycholate (DOC), taurochenodeoxycholate (TCDC), or Ringer/DNP. The integrity of the BBB was then determined by perfusing with the radiotracer [14C]mannitol for 2.5 min. Alternatively, the brains were perfusion fixed for ultrastructural assessment. At 0.2 m M DOC, the BBB remained intact and the cerebral ultrastructure was similar to the controls. At 1 m M and above, disruption of the BBB became evident. At 2 m M, the cerebral cortex became severely vacuolated, with damaged endothelium and collapsed capillaries. With TCDC, BBB disruption occurred at 0.2 m M without any apparent ultrastructural damage to the micro vasculature. Following 2 m M TCDC, similar, but less widespread, structural changes to the 2 m M DOC-perfused animals was apparent. Opening of the BBB occurred at a concentration lower than that required to cause lysis of either red blood cells or cultured cerebral endothelial cells. It is proposed that the effect of bile salts at concentrations of 1.5 m M and above is largely due to their lytic action as strong detergents on endothelial cell membranes, but that at lower concentrations a more subtle modification of the BBB occurs.

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