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Confocal imaging has shown that CELLULOSE SYNTHASE (CESA) particles move through the plasma membrane as they synthesize cellulose. However, the resolution limit of confocal microscopy circumscribes what can be discovered about these tiny biosynthetic machines. Here, we applied Structured Illumination Microscopy (SIM), which improves resolution two-fold over confocal or widefield imaging, to explore the dynamic behaviors of CESA particles in living plant cells. SIM imaging reveals that Arabidopsis thaliana CESA particles are more than twice as dense in the plasma membrane as previously estimated, helping explain the dense arrangement of cellulose observed in new wall layers. CESA particles tracked by SIM display minimal variation in velocity, suggesting coordinated control of CESA catalytic activity within single complexes and that CESA complexes might move steadily in tandem to generate larger cellulose fibrils or bundles. SIM data also reveal that CESA particles vary in their overlaps with microtubule tracks and can complete U-turns without changing speed. CESA track patterns can vary widely between neighboring cells of similar shape, implying that cellulose patterning is not the sole determinant of cellular growth anisotropy. Together, these findings highlight SIM as a powerful tool to advance CESA imaging beyond the resolution limit of conventional light microscopy., (© American Society of Plant Biologists 2021. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Tight junctions (TJs) between blood-brain barrier (BBB) endothelial cells construct a robust physical barrier, whose damage underlies BBB dysfunctions related to several neurodegenerative diseases. What makes these highly specialized BBB-TJs extremely restrictive remains unknown. Here, we use super-resolution microscopy (dSTORM) to uncover new structural and functional properties of BBB TJs. Focusing on three major components, Nano-scale resolution revealed sparse (occludin) vs. clustered (ZO1/claudin-5) molecular architecture. In mouse development, permeable TJs become first restrictive to large molecules, and only later to small molecules, with claudin-5 proteins arrangement compacting during this maturation process. Mechanistically, we reveal that ZO1 clustering is independent of claudin-5 in vivo. In contrast to accepted knowledge, we found that in the developmental context, total levels of claudin-5 inversely correlate with TJ functionality. Our super-resolution studies provide a unique perspective of BBB TJs and open new directions for understanding TJ functionality in biological barriers, ultimately enabling restoration in disease or modulation for drug delivery., Competing Interests: ES, SA, BB, OY, MZ, UD, BE, ES, GV, RD, AB No competing interests declared, (© 2021, Sasson et al.)

We introduce a random-access parallel (RAP) imaging modality that uses a novel design inspired by a Newtonian telescope to image multiple spatially separated samples without moving parts or robotics. This scheme enables near-simultaneous image capture of multiple petri dishes and random-access imaging with sub-millisecond switching times at the full resolution of the camera. This enables the RAP system to capture long-duration records from different samples in parallel, which is not possible using conventional automated microscopes. The system is demonstrated by continuously imaging multiple cardiac monolayer and Caenorhabditis elegans preparations., Competing Interests: MA, SM, BS, AT, KR, DB, ST, AC, GB No competing interests declared, (© 2021, Ashraf et al.)

Severe Acute Respiratory Syndrome Coronaviruses (SARS-CoVs), causative of major outbreaks in the past two decades, has claimed many lives all over the world. The virus effectively spreads through saliva aerosols or nasal discharge from an infected person. Currently, no specific vaccines or treatments exist for coronavirus; however, several attempts are being made to develop possible treatments. Hence, it is important to study the viral structure and life cycle to understand its functionality, activity, and infectious nature. Further, such studies can aid in the development of vaccinations against this virus. Microscopy plays an important role in examining the structure and topology of the virus as well as pathogenesis in infected host cells. This review deals with different microscopy techniques including electron microscopy, atomic force microscopy, fluorescence microscopy as well as computational methods to elucidate various prospects of this life-threatening virus., (© 2020 Wiley Periodicals LLC.)

Super-resolution microscopy can reveal the subtle biological processes hidden behind the optical diffraction barrier. Plasmonics is a key nanophotonic that combines electronics and photonics through the interaction of light with the metallic nanostructure. In this review, we survey the recent progresses on plasmonic-assisted super-resolution microscopy. The strong electromagnetic field enhancement trapped near metallic nanostructures offers a unique opportunity to manipulate the illumination scheme for overcoming the diffraction limit. Plasmonic nanoprobes, exploited as surface-enhanced Raman scattering (SERS) and plasmon-enhanced fluorescence nanoparticles, are a major category of contrast agent in super-resolution microscopy. The outstanding challenges, future developments, and potential biological applications are also discussed., (Copyright © 2020. Published by Elsevier Ltd.)

Photosynthetic membranes are typically densely packed with proteins, and this is crucial for their function in efficient trapping of light energy. Despite being crowded with protein, the membranes are fluid systems in which proteins and smaller molecules can diffuse. Fluidity is also crucial for photosynthetic function, as it is essential for biogenesis, electron transport, and protein redistribution for functional regulation. All photosynthetic membranes seem to maintain a delicate balance between crowding, order, and fluidity. How does this work in phototrophic bacteria? In this review, we focus on two types of intensively studied bacterial photosynthetic membranes: the chromatophore membranes of purple bacteria and the thylakoid membranes of cyanobacteria. Both systems are distinct from the plasma membrane, and both have a distinctive protein composition that reflects their specialized roles. Chromatophores are formed from plasma membrane invaginations, while thylakoid membranes appear to be an independent intracellular membrane system. We discuss the techniques that can be applied to study the organization and dynamics of these membrane systems, including electron microscopy techniques, atomic force microscopy, and many variants of fluorescence microscopy. We go on to discuss the insights that havebeen acquired from these techniques, and the role of membrane dynamics in the physiology of photosynthetic membranes. Membrane dynamics on multiple timescales are crucial for membrane function, from electron transport on timescales of microseconds to milliseconds to regulation and biogenesis on timescales of minutes to hours. We emphasize the open questions that remain in the field.

The Food and Drug Administration (FDA or we) is classifying the whole slide imaging system into class II (special controls). The special controls that apply to the device type are identified in this order and will be part of the codified language for the whole slide imaging system's classification. We are taking this action because we have determined that classifying the device into class II (special controls) will provide a reasonable assurance of safety and effectiveness of the device. We believe this action will also enhance patients' access to beneficial innovative devices, in part by reducing regulatory burdens.

The Food and Drug Administration (FDA or we) is classifying the automated indirect immunofluorescence microscope and software-assisted system into class II (special controls). The special controls that apply to the device type are identified in this order and will be part of the codified language for the automated indirect immunofluorescence microscope and software-assisted system's classification. We are taking this action because we have determined that classifying the device into class II (special controls) will provide a reasonable assurance of safety and effectiveness of the device. We believe this action will also enhance patients' access to beneficial innovative devices, in part by reducing regulatory burdens.

For centuries, light microscopy has been a key method in biological research, from the early work of Robert Hooke describing biological organisms as cells, to the latest in live-cell and single-molecule systems. Here, we introduce some of the key concepts related to the development and implementation of modern microscopy techniques. We briefly discuss the basics of optics in the microscope, super-resolution imaging, quantitative image analysis, live-cell imaging, and provide an outlook on active research areas pertaining to light microscopy.

The refractive index (RI) distribution can serve as a natural label for undyed cell imaging. However, the majority of images obtained through quantitative phase microscopy is integrated along the illumination angle and cannot reflect additional information about the refractive map on a certain plane. Herein, a light-field reconstruction method to image the RI map within a depth of 0.2 μm is proposed. It records quantitative phase-delay images using a four-step phase shifting method in different directions and then reconstructs a similar scattered light field for the refractive sample on the focus plane. It can image the RI of samples, transparent cell samples in particular, in a manner similar to the observation of scattering characteristics. The light-field reconstruction method is therefore a powerful tool for use in cytobiology studies., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The Food and Drug Administration (FDA) is classifying the Assisted Reproduction Embryo Image Assessment System into class II (special controls). The special controls that will apply to the device are identified in this order, and will be part of the codified language for the Assisted Reproduction Embryo Image Assessment System classification. The Agency is classifying the device into class II (special controls) in order to provide a reasonable assurance of safety and effectiveness of the device.

Various specialized imaging modalities and guided microscopic methods developed in recent years, having proven value for the evaluation of tongue disorders. The list of which includes cineradiography, pulsed ultrasound, computer-assisted tomography, isotopic scanning, electromyography, magnetic resonance, video microscopy and stereo microscopy. The basic aim of the article is to review and throw light on the importance of complete examination of the tongue and application of advanced investigations for the proper diagnosis of the tongue lesions and its usefulness to the clinician.

Precisely imaging and tracking dynamic biological processes in live cells are crucial for both fundamental research in life sciences and biomedical applications. Nonfluorescent nanoparticles are emerging as important optical probes in live-cell imaging because of their excellent photostability, large optical cross sections, and low cytotoxicity. Here, we provide a review of recent development in optical imaging of nonfluorescent nanoparticle probes and their applications in dynamic tracking and biosensing in live cells. A brief discussion on cytotoxicity of nanoparticle probes is also provided., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: Visual findings summarized in the figures and tables of academic papers are invaluable sources for biomedical researchers. Captions associated with the visual findings are often neglected while retrieving biomedical images in published academic papers., Objectives: This study is to assess caption-based topical descriptors for microscopic images of breast neoplasms, as published in academic papers retrieved through the PubMed Central database., Method: Human indexers as well as an automatic keyword finder called TAPoR generated the topical descriptors from collected captions. The study then compared the human-generated descriptors to machine-generated descriptors. Finally, a set of core descriptors was developed from both sets and automatically mapped into the Unified Medical Language System's (UMLS) Metathesaurus through a MetaMap Transfer engine., Results: Major topical descriptors included histologic disease names, laboratory procedures, genetic functions and components. Human indexers provided more relevant descriptors than TAPoR. The UMLS Metathesaurus identified several semantic types including Indicator, Reagent, or Diagnostic Aid; Organic Chemical; Laboratory Procedure; Spatial Concept; Qualitative Concept; and Quantitative Concept., Discussion: The findings suggest that caption-based descriptors can complement title or abstract-based literature indexing for figure image retrieval in articles. With respect to forming a metadata framework for online microscopic image description, the semantic types can be used as a core metadata set. In this regard, this finding can be used for standardising a microscopic image description protocol to train medical students., Conclusions: It is incumbent upon libraries and other information agencies to promote and maintain an interest in the opportunities and challenges associated with biomedical imaging.

Setting: Designated microscopy centres (DMC) and additional microscopy centres (AMC) performing sputum acid-fast bacilli (AFB) microscopy, the District TB Centre (DTC) and a reference laboratory (RL)., Objectives: To ascertain the feasibility of adopting lot sampling of AFB smears and to assess the performance of MCs employing Senior Tuberculosis Laboratory Supervisors (STLS) with no knowledge about the principles of quality assurance of AFB microscopy and RL-based laboratory technicians with training on quality assurance for blinded checking of AFB smears., Methods: Slides from MCs were transported to the DTC and the RL; 20 smears per month per MC were selected systematically; 1547 slides from DMCs and 726 from AMCs were checked, respectively, by STLSs at the DTC and by RL laboratory technicians. Discrepancies were resolved by referee., Results: The discrepancy between MC laboratory technicians and STLSs at the DTC was 4.7%, compared to 1% at the RL. The STLSs and RL-based laboratory technicians had 70 and 2 errors, respectively., Conclusions: Lot sampling of AFB smears is feasible under field conditions. Assessment of MCs was more valid with RL-based technicians trained in principles of quality assurance of sputum AFB microscopy than with STLSs with no such training and working in the field.

Although CPT 1999 contains fewer changes than in past years, coders should take some time to learn them by: familiarizing themselves with the new symbols + and [symbol: see text] reviewing Appendix A for a complete list of modifiers as well as modifiers used in the ambulatory surgery center hospital outpatient setting; reviewing Appendix E for a complete list of add-on codes; reviewing Appendix F for a list of modifier-51-exempt codes; consulting the excludes note found above code 69,990 to identify procedures exempt from the use of the new operating microscope code; examining the specific codes used to identify bronchoscopic procedures; reviewing the parenthetical notes found after code 15,001, directing the coder to also assign the appropriate code for lesion excision; reviewing the changes associated with the coding of destruction of lesions understanding the changes in immunization code assignment; consulting payers for specific reimbursement guidelines.