X-ray diffraction and second harmonic imaging reveal new insights into structural alterations caused by pressure-overload in murine hearts

Abstract We demonstrate a label-free imaging approach to study cardiac remodeling of fibrotic and hypertrophic hearts, bridging scales from the whole organ down to the molecular level. To this end, we have used mice subjected to transverse aortic constriction and imaged adjacent cardiac tissue sections by microfocus X-ray diffraction and second harmonic generation (SHG) imaging. In this way, the acto-myosin structure was probed in a spatially resolved manner for entire heart sections. From the recorded diffraction data, spatial maps of diffraction intensity, anisotropy and orientation were obtained, and fully automated analysis depicted the acto-myosin filament spacing and direction. X-ray diffraction presented an overview of entire heart sections and revealed that in regions of severe cardiac remodeling the muscle mass is partly replaced by connective tissue and the acto-myosin lattice spacing is increased at these regions. SHG imaging revealed sub-cellular structure of cardiac tissue and complemented the findings from X-ray diffraction by revealing micro-level distortion of myofibrils, immune cell infiltration at regions of cardiac remodeling and the development of fibrosis down to the scale of a single collagen fibril. Overall, our results show that both X-ray diffraction and SHG imaging can be used for label-free and high-resolution visualization of cardiac remodeling and fibrosis progression at different stages in a cardiac pressure-overload mouse model that cannot be achieved by conventional histology.

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X-ray diffraction analysis of matter taking into account the second harmonic in the scattering of powerful ultrashort pulses of an electromagnetic field

Scientific Reports ◽

10.1038/s41598-021-83183-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

M. K. Eseev ◽

A. A. Goshev ◽

K. A. Makarova ◽

D. N. Makarov

Keyword(s):

Electromagnetic Field ◽

Diffraction Analysis ◽

Diffraction Pattern ◽

Second Harmonic ◽

Ultrashort Pulses ◽

X Ray Diffraction ◽

X Ray ◽

Scattering Spectra ◽

Technical Possibility ◽

2D And 3D

AbstractIt is well known that the scattering of ultrashort pulses (USPs) of an electromagnetic field in the X-ray frequency range can be used in diffraction analysis. When such USPs are scattered by various polyatomic objects, a diffraction pattern appears from which the structure of the object can be determined. Today, there is a technical possibility of creating powerful USP sources and the analysis of the scattering spectra of such pulses is a high-precision instrument for studying the structure of matter. As a rule, such scattering occurs at a frequency close to the carrier frequency of the incident USP. In this work, it is shown that for high-power USPs, where the magnetic component of USPs cannot be neglected, scattering at the second harmonic appears. The scattering of USPs by the second harmonic has a characteristic diffraction pattern which can be used to judge the structure of the scattering object; combining the scattering spectra at the first and second harmonics therefore greatly enhances the diffraction analysis of matter. Scattering spectra at the first and second harmonics are shown for various polyatomic objects: examples considered are 2D and 3D materials such as graphene, carbon nanotubes, and hybrid structures consisting of nanotubes. The theory developed in this work can be applied to various multivolume objects and is quite simple for X-ray structural analysis, because it is based on analytical expressions.

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A Label-Free Electrochemical Aptasensor for the Rapid Detection of Tetracycline Based on Ordered Mesoporous Carbon–Fe3O4

Australian Journal of Chemistry ◽

10.1071/ch17503 ◽

2018 ◽

Vol 71 (3) ◽

pp. 170 ◽

Cited By ~ 2

Author(s):

Xuejia Zhan ◽

Guangzhi Hu ◽

Thomas Wagberg ◽

Dongwei Zhang ◽

Pei Zhou

Keyword(s):

Photoelectron Spectroscopy ◽

Mesoporous Carbon ◽

Physical Adsorption ◽

Differential Pulse ◽

Ordered Mesoporous Carbon ◽

Label Free ◽

X Ray Diffraction ◽

X Ray ◽

Ordered Mesoporous ◽

Modification Procedure

A novel aptasensor based on a tetracycline (TET) aptamer immobilized by physical adsorption on an ordered mesoporous carbon–Fe3O4 (OMC-Fe3O4)-modified screen-printed electrode surface was successfully fabricated. OMC-Fe3O4 was characterized by scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The modification procedure of the aptasensor was characterized by cyclic voltammetry. Interaction between the TET aptamer and target was determined by differential pulse voltammetry. Under optimal conditions, the proposed aptasensor exhibited good electrochemical sensitivity to TET in a concentration range of 5 nM to 10 μM, with a detection limit of 0.8 nM (S/N = 3). This aptasensor exhibited satisfactory specificity, reproducibility, and stability.

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Myosin filament-based regulation of the dynamics of contraction in heart muscle

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1920632117 ◽

2020 ◽

Vol 117 (14) ◽

pp. 8177-8186 ◽

Cited By ~ 4

Author(s):

Elisabetta Brunello ◽

Luca Fusi ◽

Andrea Ghisleni ◽

So-Jin Park-Holohan ◽

Jesus G. Ovejero ◽

...

Keyword(s):

Heart Muscle ◽

Time Course ◽

Myosin Filament ◽

X Ray Diffraction ◽

X Ray ◽

Myosin Binding Protein ◽

Myosin Binding Protein C ◽

Myosin Binding ◽

Stress Sensing ◽

Myosin Motors

Myosin-based mechanisms are increasingly recognized as supplementing their better-known actin-based counterparts to control the strength and time course of contraction in both skeletal and heart muscle. Here we use synchrotron small-angle X-ray diffraction to determine the structural dynamics of local domains of the myosin filament during contraction of heart muscle. We show that, although myosin motors throughout the filament contribute to force development, only about 10% of the motors in each filament bear the peak force, and these are confined to the filament domain containing myosin binding protein-C, the “C-zone.” Myosin motors in domains further from the filament midpoint are likely to be activated and inactivated first in each contraction. Inactivated myosin motors are folded against the filament core, and a subset of folded motors lie on the helical tracks described previously. These helically ordered motors are also likely to be confined to the C-zone, and the associated motor conformation reforms only slowly during relaxation. Myosin filament stress-sensing determines the strength and time course of contraction in conjunction with actin-based regulation. These results establish the fundamental roles of myosin filament domains and the associated motor conformations in controlling the strength and dynamics of contraction in heart muscle, enabling those structures to be targeted to develop new therapies for heart disease.

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The Effect of Polyvinyl Alcohol Concentration on the Growth Kinetics of KTiOPO4 Nanoparticles Synthesized by the Co-precipitation Method

HighTech and Innovation Journal ◽

10.28991/hij-2020-01-04-06 ◽

2020 ◽

Vol 1 (4) ◽

pp. 187-193

Author(s):

Elaheh Gharibshahian

Keyword(s):

Polyvinyl Alcohol ◽

Shape Control ◽

Second Harmonic ◽

Precipitation Method ◽

Capping Agent ◽

X Ray Diffraction ◽

X Ray ◽

Size And Shape ◽

Diffraction Patterns ◽

Co Precipitation

KTiOPO4 nanoparticles are known as the best candidate to utilize for second-harmonic generation in multiphoton microscopes and bio labels. Size and shape are important and effective parameters to control the properties of nanoparticles. In this paper, we will investigate the role of capping agent concentration on the size and shape control of KTP nanoparticles. We synthesized KTP nanoparticles by the co-precipitation method. Polyvinyl alcohol with different mole ratios to titanium ion (1:3, 1:2, 1:1) was used as a capping agent. Products were examined by X-ray diffraction patterns and scanning electron microscopy analyses. X-ray diffraction patterns confirmed the formation of the KTP structure. The biggest (56.36nm) and smallest (39.42nm) grain size were obtained by 1:3 and 1:1 mole ratios of capping agent, respectively. Dumbly, spherical and polyhedral forms of KTP nanoparticles were observed by the change in capping agent mole ratio. The narrowest size distribution of KTiOPO4 nanoparticles was obtained at 1:1 mole ratio of capping agent. Doi: 10.28991/HIJ-2020-01-04-06 Full Text: PDF

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Tuning the Linear and Nonlinear Optical Properties of Pyrene-Pyridine Chromophores by Protonation and Complexation to d10 Metal Centers †

Inorganics ◽

10.3390/inorganics7030038 ◽

2019 ◽

Vol 7 (3) ◽

pp. 38 ◽

Cited By ~ 2

Author(s):

Elena Lucenti ◽

Alessandra Forni ◽

Daniele Marinotto ◽

Andrea Previtali ◽

Stefania Righetto ◽

...

Keyword(s):

Nonlinear Optical ◽

Second Harmonic ◽

Protonated Form ◽

Lewis Acidity ◽

X Ray Diffraction ◽

Metal Centers ◽

X Ray ◽

Nlo Response ◽

D10 Metal ◽

Simple Exposure

The linear and second-order nonlinear optical (NLO) properties of two pyrene-pyridine chromophores, namely, 4-(pyren-1-yl)pyridine (L1) and 4-(2-(pyren-1-yl)ethyl)pyridine (L2), were investigated and modulated by performing protonation/deprotonation cycles or by complexation to d10 metal centers such as Zn(II) and Cu(I) to form the monomeric [Zn(CH3CO2)2(L1)2] complex and the [CuI(L2)]n coordination polymer, respectively. The structures of L1, L2, [Zn(CH3CO2)2(L1)2] and [CuI(L2)]n were determined by means of single-crystal X-ray diffraction studies. The NLO response, measured by the electric-field-induced second harmonic generation (EFISH) technique, was positive for both chromophores and showed an inversion of the sign after exposure to HCl vapors. This process was completely reversible and the original values were restored by simple exposure to NH3 vapors. Coordination of L1 to Zn(II) also resulted in a negative NLO response, although smaller in magnitude compared to the protonated form, due to the weak Lewis acidity of the “Zn(CH3CO2)2” fragment. The results were also interpreted on the basis of DFT/TDDFT calculations.

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Synthesis, growth, structure and characterization of molybdenum zinc thiourea complex crystals

Acta Crystallographica Section B Structural Science Crystal Engineering and Materials ◽

10.1107/s2052520615005922 ◽

2015 ◽

Vol 71 (3) ◽

pp. 285-292 ◽

Cited By ~ 1

Author(s):

M. Rajasekar ◽

K. Muthu ◽

A. Aditya Prasad ◽

R. Agilandeshwari ◽

SP Meenakshisundaram

Keyword(s):

Single Crystal ◽

Diffraction Analysis ◽

Intermolecular Interactions ◽

Crystal Packing ◽

Second Harmonic ◽

Morphological Changes ◽

Strong Interactions ◽

X Ray Diffraction ◽

X Ray ◽

Cell Parameters

Single crystals of molybdenum-incorporated tris(thiourea)zinc(II) sulfate (MoZTS) are grown by the slow evaporation solution growth technique. Crystal composition as determined by single-crystal X-ray diffraction analysis reveals that it belongs to the orthorhombic system with space groupPca21and cell parametersa= 11.153 (2),b= 7.7691 (14),c= 15.408 (3) Å,V= 1335.14 (4) Å3andZ= 4. The surface morphological changes are studied by scanning electron microscopy. The vibrational patterns in FT–IR are used to identify the functional group and TGA/DTA (thermogravimetric analysis/differential thermal analysis) indicates the stability of the material. The structure and the crystallinity of the material were confirmed by powder X-ray diffraction analysis and the simulated X-ray diffraction (XRD) closely matches the experimental one with varied intensity patterns. The band gap energy is estimated using diffuse reflectance data by the application of the Kubelka–Munk algorithm. The relative second harmonic generation (SHG) efficiency measurements reveal that MoZTS has an efficiency comparable to that of tris(thiourea)zinc(II) sulfate (ZTS). Hirshfeld surfaces were derived using single-crystal X-ray diffraction data. Investigation of the intermolecular interactions and crystal packingviaHirshfeld surface analysis reveal that the close contacts are associated with strong interactions. Intermolecular interactions as revealed by the fingerprint plot and close packing could be the possible reasons for facile charge transfer leading to SHG activity.

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Second-harmonic generation and x-ray diffraction studies of the pretransitional region and polar phase in relaxorK(1−x)LixTaO3

Physical Review B ◽

10.1103/physrevb.75.184113 ◽

2007 ◽

Vol 75 (18) ◽

Cited By ~ 35

Author(s):

Hiroko Yokota ◽

Yoshiaki Uesu ◽

Charlotte Malibert ◽

Jean-Michel Kiat

Keyword(s):

Second Harmonic Generation ◽

Harmonic Generation ◽

Second Harmonic ◽

Polar Phase ◽

X Ray Diffraction ◽

X Ray

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Guiding synchrotron X-ray diffraction by multimodal video-rate protein crystal imaging

Journal of Synchrotron Radiation ◽

10.1107/s1600577516005919 ◽

2016 ◽

Vol 23 (4) ◽

pp. 959-965 ◽

Cited By ~ 6

Author(s):

Justin A. Newman ◽

Shijie Zhang ◽

Shane Z. Sullivan ◽

Ximeng Y. Dow ◽

Michael Becker ◽

...

Keyword(s):

Second Harmonic ◽

Photon Counting ◽

Protein Crystal ◽

X Ray Diffraction ◽

Incident Wavelength ◽

X Ray ◽

Two Photon ◽

Simultaneous Imaging ◽

Order Of Magnitude ◽

Simple Change

Synchronous digitization, in which an optical sensor is probed synchronously with the firing of an ultrafast laser, was integrated into an optical imaging station for macromolecular crystal positioning prior to synchrotron X-ray diffraction. Using the synchronous digitization instrument, second-harmonic generation, two-photon-excited fluorescence and bright field by laser transmittance were all acquired simultaneously with perfect image registry at up to video-rate (15 frames s−1). A simple change in the incident wavelength enabled simultaneous imaging by two-photon-excited ultraviolet fluorescence, one-photon-excited visible fluorescence and laser transmittance. Development of an analytical model for the signal-to-noise enhancement afforded by synchronous digitization suggests a 15.6-fold improvement over previous photon-counting techniques. This improvement in turn allowed acquisition on nearly an order of magnitude more pixels than the preceding generation of instrumentation and reductions of well over an order of magnitude in image acquisition times. These improvements have allowed detection of protein crystals on the order of 1 µm in thickness under cryogenic conditions in the beamline. These capabilities are well suited to support serial crystallography of crystals approaching 1 µm or less in dimension.

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Structure and Properties of [(CH2OH)3CNH3]H2AsO4

Zeitschrift für Naturforschung A ◽

10.1515/zna-2003-1207 ◽

2003 ◽

Vol 58 (12) ◽

pp. 722-726 ◽

Cited By ~ 1

Author(s):

A. Waśkowska ◽

S. Dacko ◽

Z. Czapla

Keyword(s):

Phase Transition ◽

Second Harmonic ◽

Three Dimensional ◽

Structure And Properties ◽

X Ray Diffraction ◽

Temperature Dependent ◽

X Ray ◽

Dimensional Network ◽

Network Of Hydrogen Bonds ◽

Dependent Behaviour

Crystals of [(CH2OH)3CNH3]H2AsO4 have been grown, and X-ray diffraction analysis has shown them to be monoclinic, with space group P21. A three-dimensional network of hydrogen bonds of the type O-H. . . O and N-H. . . O forms strong cation-cation and cation-anion linkages. Stabilizing the structure, they create favourable conditions in the crystal to be polar. The temperature dependent behaviour of the dielectric permittivity, measured along three crystal axes in the range 100 - 300 K, did not show any evidence for a phase transition, while the pyroelectric properties of the crystal confirmed the lack of a centre of symmetry. These polar features locate [(CH2OH)3CNH3]H2AsO4 among the materials applicable to electrooptics and for the second harmonic generation.

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