Multidimensional Characterization of the Physiological State of Hematococcuspluvialis Using Scanning Structured Illumination Super-Resolution Microscopy.

(HP) is a freshwater alga known for its ability to accumulate the potent antioxidant astaxanthin, which has extensive applications in aquaculture, pharmaceuticals, and cosmetics. Astaxanthin rapidly accumulates under unfavorable environmental conditions. However, the mechanisms of astaxanthin accumulation under various stress conditions remain unclear.

In Situ Structural Characterization of Cardiomyocyte Microenvironment by Multimodal STED Microscopy.

Within the myocardium, cardiomyocytes reside in a complex and dynamic extracellular matrix (ECM) consisting of a basement membrane (BM) and interstitial matrix. The interactions between cardiomyocytes and the myocardial ECM play a critical role in maintaining cardiac geometry and function throughout cardiac development and in adult hearts. Understanding how the structural changes of the myocardial ECM affect cardiomyocyte function requires knowledge of pericellular structures.

Quantification of cardiac capillarization in basement-membrane-immunostained myocardial slices using Segment Anything Model.

Decreased myocardial capillary density has been reported as an important histopathological feature associated with various heart disorders. Quantitative assessment of cardiac capillarization typically involves double immunostaining of cardiomyocytes (CMs) and capillaries in myocardial slices. In contrast, single immunostaining of basement membrane protein is a straightforward approach to simultaneously label CMs and capillaries, presenting fewer challenges in background staining.

CRISPR-powered optothermal nanotweezers: Diverse bio-nanoparticle manipulation and single nucleotide identification.

Optothermal nanotweezers have emerged as an innovative optical manipulation technique in the past decade, which revolutionized classical optical manipulation by efficiently capturing a broader range of nanoparticles. However, the optothermal temperature field was merely employed for in-situ manipulation of nanoparticles, its potential for identifying bio-nanoparticles remains largely untapped. Hence, based on the synergistic effect of optothermal manipulation and CRIPSR-based bio-detection, we developed CRISPR-powered optothermal nanotweezers (CRONT).

Highly-Adaptable Optothermal Nanotweezers for Trapping, Sorting, and Assembling across Diverse Nanoparticles.

Optical manipulation of various kinds of nanoparticles is vital in biomedical engineering. However, classical optical approaches demand higher laser power and are constrained by diffraction limits, necessitating tailored trapping schemes for specific nanoparticles. They lack a universal and biocompatible tool to manipulate nanoparticles of diverse sizes, charges, and materials.

Management of autofluorescence in formaldehyde-fixed myocardium: choosing the right treatment.

Autofluorescence (AF) poses challenges for detecting proteins of interest in situ when employing immunofluorescence (IF) microscopy. This interference is particularly pronounced in strongly autofluorescent tissues such as myocardium, where tissue AF can be comparable to IF. Although various histochemical methods have been developed to achieve effective AF suppression in different types of tissue, their applications on myocardial  samples have not been well validated.

Multi-color two-photon scanning structured illumination microscopy imaging of live cells.

Multi-color two-photon microscopy imaging of live cells is essential in biology. However, the limited diffraction resolution of conventional two-photon microscopy restricts its application to subcellular organelle imaging. Recently, we developed a laser scanning two-photon non-linear structured illumination microscope (2P-NLSIM), whose resolution improved three-fold.

Cooperation between myofibril growth and costamere maturation in human cardiomyocytes.

Costameres, as striated muscle-specific cell adhesions, anchor both M-lines and Z-lines of the sarcomeres to the extracellular matrix. Previous studies have demonstrated that costameres intimately participate in the initial assembly of myofibrils. However, how costamere maturation cooperates with myofibril growth is still underexplored.

Corrigendum: High-Sensitive Surface Plasmon Resonance Imaging Biosensor Based on Dual-Wavelength Differential Method.

[This corrects the article DOI: 10.3389/fchem.2021.

Optothermophoretic flipping method for biomolecule interaction enhancement.

The widely used surface-based biomolecule sensing scheme has greatly facilitated the investigation of protein-protein interactions in lab-on-a-chip microfluidic systems. However, in most biosensing schemes, the interactions are driven in a passive way: The overall sensing time and sensitivity are totally dependent on the Brownian diffusion process, which has greatly hindered their efficiency, especially at low concentration levels or single-molecule analysis. To break this limitation, we developed an all-optical active method termed optothermophoretic flipping (OTF).

Molecular mechanisms of cardiac actomyosin transforming from rigor state to post-rigor state.

Sudden cardiac death contributed to half of all deaths from cardiovascular diseases. The mechanism of the kinetic cycle of cardiac myosin is crucial for heart protection and drug development. The state change in the myosin kinetic cycle from the rigor state to the post-rigor state is fundamental to explain binding and dissociation.

High-efficiency 3D reconstruction with a uniaxial MEMS-based fringe projection profilometry.

Micro-Electro-Mechanical System (MEMS) scanning is increasingly popular in 3D surface measurement with the merits of the compact structure and high frame-rate. In this paper, we achieve real-time fringe structured 3D reconstruction by using a uniaxial MEMS-based projector. To overcome the limitations on uniaxial MEMS-based projector of lensless structure and unidirectional fringe projection, a novel isophase plane model is proposed, in which the laser line from MEMS-based projector is regarded as an isophase plane.

Phase interrogation surface plasmon resonance hyperspectral imaging sensor for multi-channel high-throughput detection.

Phase interrogation surface plasmon resonance (SPR) imaging is, in principle, suitable in multiple samples and high-throughput detection, but the refractive index difference of various samples can be largely varied, while the dynamic range of phase interrogation SPR is narrow. So it is difficult to perform multi-sample detection in phase interrogation mode. In this paper, we successfully designed a multi-channel phase interrogation detection SPR imaging sensing scheme based on a common optical interference path between p- and s-polarized light without using any mechanical moving components.

Hybrid method for representing ions in implicit solvation calculations.

Fast and accurate calculations of the electrostatic features of highly charged biomolecules such as DNA, RNA, and highly charged proteins are crucial and challenging tasks. Traditional implicit solvent methods calculate the electrostatic features quickly, but these methods are not able to balance the high net biomolecular charges effectively. Explicit solvent methods add unbalanced ions to neutralize the highly charged biomolecules in molecular dynamic simulations, which require more expensive computing resources.

Ultrafast Surface Plasmon Resonance Imaging Sensor via the High-Precision Four-Parameter-Based Spectral Curve Readjusting Method.

A variety of surface plasmon resonance (SPR) sensing devices have been extensively used in biochemical detection for their characteristics of label-free, highly sensitive, and faster detecting. Among them, the spectrum-based SPR sensing devices have offered us great advantages in high-throughput sensing due to their large dynamic range and the possibility of detection resolution similar to that offered by angle interrogation. This paper demonstrates a spectrum-based SPR imaging sensing system with fast wavelength scanning capability achieved by an acousto-optic tunable filter (AOTF) and a low-cost and speckle-free halogen lamp implemented as the SPR excitation source.

-Like Morphology of Intercalated Discs Achieved in a Neonatal Cardiomyocyte Culture Model.

cultures to be used in various analytical investigations of cardiomyocyte (CM) growth and function for enhancing insight into physiological and pathological mechanisms should closely express morphology. The aim of the studies is to explore how to use microfabrication and physical-cue-addition techniques to establish a neonatal rat CM culture model that expresses an end-to-end connected rod shape with -like intercalated discs (ICDs). Freshly isolated neonatal rat CMs were cultured on microgrooved polydimethylsiloxane substrate.

Phase interrogation SPR sensing based on white light polarized interference for wide dynamic detection range.

A phase surface plasmon resonance (SPR) sensing technology based on white light polarized interference in common-path geometry is reported. A halogen lamp is used as the excitation source of the SPR sensor. The fixed optical path difference (OPD) between p- and s-polarized light is introduced by a birefringence crystal to produce sinusoidal spectral interference fringes.

Changes in the crystallographic structures of cardiac myosin filaments detected by polarization-dependent second harmonic generation microscopy.

Detecting the structural changes caused by volume and pressure overload is critical to comprehending the mechanisms of physiologic and pathologic hypertrophy. This study explores the structural changes at the crystallographic level in myosin filaments in volume- and pressure-overloaded myocardia through polarization-dependent second harmonic generation microscopy. Here, for the first time, we report that the ratio of nonlinear susceptibility tensor components increased significantly in volume- and pressure-overloaded myocardial tissues compared with the ratio in normal mouse myocardial tissues.

Light-field-based absolute phase unwrapping.

Ambiguity caused by a wrapped phase is an intrinsic problem in fringe projection-based 3D shape measurement. Among traditional methods for avoiding phase ambiguity, spatial phase unwrapping is sensitive to sensor noise and depth discontinuity, and temporal phase unwrapping requires additional encoding information that leads to an increase of image sequence acquisition time or a reduction of fringe contrast. Here, to the best of our knowledge, we report a novel method of absolute phase unwrapping based on light field imaging.

Light field 3D measurement using unfocused plenoptic cameras.

This Letter reports a novel method to establish the metric relationship of depth value between object space and image space for unfocused plenoptic cameras. A three-dimensional (3D) measurement system was introduced to precisely construct benchmarks and matching features to compute the metric depths in the object space and the corresponding depth values in the image space for metric calibration. After metric calibration, precise measurement of the depth dimension was possible.

Ray calibration and phase mapping for structured-light-field 3D reconstruction.

In previous work, we presented a structured light field (SLF) method combining light field imaging with structured illumination to perform multi-view depth measurement. However, the previous work just accomplishes depth rather than 3D reconstruction. In this paper, we propose a novel active method involving ray calibration and phase mapping, to achieve SLF 3D reconstruction.

Universal phase-depth mapping in a structured light field.

Technologies and devices for light field imaging have recently been developed for both industrial applications and scientific research to achieve excellent imaging properties. In our previous work, we combined light field imaging with structured illumination to propose a structured light field method in which multidirectional depth estimation can be performed for high-quality 3D imaging. However, the projection axis was implicitly assumed to be perpendicular to the reference plane, which is hard to meet in practice.