On-line correlative imaging of cryo-PALM and soft X-ray tomography for identification of subcellular structures.

Correlative imaging of fluorescence microscopy and soft X-ray microscopy plays a crucial role in exploring the relationship between structure and function in cellular biology. However, the current correlative imaging methods are limited either to off-line or low-resolution fluorescence imaging. In this study, we developed an integrated on-line cryogenic photoactivated localization microscopy (cryo-PALM) system at a soft X-ray microscopy station.

Dual-mode harvest solar energy for photothermal CuSe biomineralization and seawater desalination by biotic-abiotic hybrid.

Biotic-abiotic hybrid photocatalytic system is an innovative strategy to capture solar energy. Diversifying solar energy conversion products and balancing photoelectron generation and transduction are critical to unravel the potential of hybrid photocatalysis. Here, we harvest solar energy in a dual mode for CuSe nanoparticles biomineralization and seawater desalination by integrating the merits of Shewanella oneidensis MR-1 and biogenic nanoparticles.

Detection of early pulmonary emphysema by multi-contrast x-ray Talbot-Lau interferometer.

Background: Pulmonary emphysema is a part of chronic obstructive pulmonary disease, which is an irreversible chronic respiratory disease. In order to avoid further damage to lung tissue, early diagnosis and treatment of pulmonary emphysema is essential.

Purpose: Early pulmonary emphysema diagnosis is difficult with conventional radiographic imaging.

Near-Native Imaging of Label-Free Silver Nanoparticles-Triggered 3D Subcellular Ultrastructural Reorganization in Microalgae.

Understanding the spatial orientation of nanoparticles and the corresponding subcellular architecture events favors uncovering fundamental toxic mechanisms and predicting response pathways of organisms toward environmental stressors. Herein, we map the spatial location of label-free citrate-coated Ag nanoparticles (Cit-AgNPs) and the corresponding subcellular reorganization in microalgae by a noninvasive 3D imaging approach, cryo-soft X-ray tomography (cryo-SXT). Cryo-SXT near-natively displays the 3D maps of Cit-AgNPs presenting in rarely identified sites, namely, extracellular polymeric substances (EPS) and the cytoplasm.

High energy x-ray Talbot-Lau interferometer employing a microarray anode-structured target source to extend the field of view.

. High energy and large field of view (FOV) phase contrast imaging is crucial for biological and even medical applications. Although some works have devoted to achieving a large FOV at high energy through bending gratings and so on, which would be extremely challenging in medical high energy imaging.

On-Line Fluorescence Microscopy for Identification and Imaging of Apoptotic Cell with Synchrotron-Based Soft X-ray Tomography.

Synchrotron-based soft X-ray tomography (SXT), providing three-dimensional morphology and quantitative distribution of linear absorption coefficient (LAC) of the imaged objects, is widely used in many fields to obtain ultra-structure images, especially in cellular imaging. Off-line fluorescence microscopies (FMs) are combined to identify the type of organelles and status of cells. However, deformation and displacement usually occur during the transfer and loading process, which decreases the precision of two-modal images' registration.

AQDS Activates Extracellular Synergistic Biodetoxification of Copper and Selenite via Altering the Coordination Environment of Outer-Membrane Proteins.

The biotransformation of heavy metals in the environment is usually affected by co-existing pollutants like selenium (Se), which may lower the ecotoxicity of heavy metals, but the underlying mechanisms remain unclear. Here, we shed light on the pathways of copper (Cu) and selenite (SeO) synergistic biodetoxification by MR-1 and illustrate how such processes are affected by anthraquinone-2,6-disulfonate (AQDS), an analogue of humic substances. We observed the formation of copper selenide nanoparticles (CuSe) from synergistic detoxification of Cu and SeO in the periplasm.

Regulating the synthesis rate and yield of bio-assembled FeS nanoparticles for efficient cancer therapy.

Biosynthesis has gained growing interest due to its energy efficiency and environmentally benign nature. Recently, biogenic iron sulfide nanoparticles (FeS NPs) have exhibited excellent performance in environmental remediation and energy recovery applications. However, their biosynthesis regulation strategy and application prospects in the biomedical field remain to be explored.

The immunogenic reaction and bone defect repair function of ε-poly-L-lysine (EPL)-coated nanoscale PCL/HA scaffold in rabbit calvarial bone defect.

Tissue engineering is a promising strategy for bone tissue defect reconstruction. Immunogenic reaction, which was induced by scaffolds degradation or contaminating microorganism, influence cellular activity, compromise the efficiency of tissue engineering, or eventually lead to the failure of regeneration. Inhibiting excessive immune response through modulating scaffold is critical important to promote tissue regeneration.

Roles of cation efflux pump in biomineralization of cadmium into quantum dots in Escherichia coli.

Cadmium (Cd) is a typical and widely present toxic heavy metals in environments. Biomineralization of Cd ions could alleviate the toxicity and produce valuable products in certain waste streams containing selenite. However, the impact of the intrinsic Cd(II) efflux system on the biotransformation process remains unrevealed.

Intracellular Hybrid Biosystem in a Protozoan to Trigger Visible-Light-Driven Photocatalysis.

Incorporating artificial photosensitizers with microorganisms has recently been recognized as an effective way to convert light energy into chemical energy. However, the incorporated biosystem is usually constructed in an extracellular manner and is vulnerable to the external environment. Here, we develop an intracellular hybrid biosystem in a higher organism protozoa , in which the synthesized CdS nanoparticles trigger photoreduction of nitrobenzene into aniline under visible-light irradiation.

Phosphate-Suppressed Selenite Biotransformation by .

Biotransformation of selenite to valuable elemental selenium nanoparticles (Se) is a promising avenue to remediate seleniferous environments and simultaneously recover selenium (Se). However, the underlying oxyanion competition and selenite transformation mechanism in prokaryotes are poorly understood. In this work, the impacts of phosphate on selenite uptake and transformation were elucidated with and its mutant deficient in phosphate transport as model microbial strains.

Raman micro-spectroscopy monitoring of cytochrome c redox state in Candida utilis during cell death under low-temperature plasma-induced oxidative stress.

Oxidative stress may result in different modes of cell death, such as necrosis, apoptosis and necroptosis. Currently, researchers are still striving to develop efficient tools/methods to distinguish the cell death modes in direct and label-free ways. In this study, we attempted to employ Raman micro-spectroscopy to observe the molecular changes in Candida utilis cells under oxidative stress induced by low-temperature plasma (LTP) and explore the spectroscopic biomarkers for the modes of cell death under oxidative stress.

Fluorescence Sensor Based on Biosynthetic CdSe/CdS Quantum Dots and Liposome Carrier Signal Amplification for Mercury Detection.

Mercury (Hg), as a highly harmful environmental pollutant, poses severe ecological and health risks even at low concentrations. Accurate and sensitive methods for detecting Hg ions in aquatic environments are highly needed. In this work, we developed a highly sensitive fluorescence sensor for Hg detection with an integrated use of biosynthetic CdSe/CdS quantum dots (QDs) and liposome carrier signal amplification.

Study on antibacterial properties and cytocompatibility of EPL coated 3D printed PCL/HA composite scaffolds.

Biomaterial scaffolds play a critical role in bone tissue engineering. Moreover, 3D printing technology has enormous advantage in the manufacture of bioengineering scaffolds for patient-specific bone defect treatments. In order to provide an aseptic environment for bone regeneration, ε-poly-l-lysine (EPL), an antimicrobic cationic polypeptide, was used for surface modification of 3D printed polycaprolactone/hydroxyapatite (PCL/HA) scaffolds which were fabricated by fused deposition modeling (FDM) technology.

Biogenic Quantum Dots for Sensitive, Label-Free Detection of Mercury Ions.

Nanoparticle-based fluorescent probes, typically fabricated by a chemical synthesis route, have been widely used for monitoring trace heavy metals in environments. However, the high-cost and complicated, aggressive fabrication processes restrict their widespread application. In this work, we report the first use of biogenic quantum dots (Bio-QDs) as a highly sensitive, low-cost fluorescent probe for label-free detection of mercury ions (Hg), with comparable performance to conventional chemically synthesized counterparts.

Substrate Metabolism-Driven Assembly of High-Quality CdS Se Quantum Dots in Escherichia coli: Molecular Mechanisms and Bioimaging Application.

Biosynthesis offers opportunities for cost-effective and sustainable production of semiconductor quantum dots (QDs), but is currently restricted by poor controllability on the synthesis process, resulting from limited knowledge on the assembly mechanisms and the lack of effective control strategies. In this work, we provide molecular-level insights into the formation mechanism of biogenic QDs (Bio-QDs) and its connection with the cellular substrate metabolism in Escherichia coli. Strengthening the substrate metabolism for producing more reducing power was found to stimulate the production of several reduced thiol-containing proteins (including glutaredoxin and thioredoxin) that play key roles in Bio-QDs assembly.

Selenium Stimulates Cadmium Detoxification in Caenorhabditis elegans through Thiols-Mediated Nanoparticles Formation and Secretion.

Antagonism between heavy metal and selenium (Se) could significantly affect their biotoxicity, but little is known about the mechanisms underlying such microbial-mediated antagonistic processes as well as the formed products. In this work, we examined the cadmium (Cd)-Se interactions and their fates in Caenorhabditis elegans through in vivo and in vitro analysis and elucidated the machinery of Se-stimulated Cd detoxification. Although the Se introduction induced up to 3-fold higher bioaccumulation of Cd in C.

Synthesis of CdSSe quantum dots in a protozoa Tetrahymena pyriformis.

Quantum dots (QDs) are recognized as the excellent fluorescence and photochemical materials to be applied in bioimaging, biomedical, and solar cell fields. Biosynthesized QDs (bio-QDs) have attracted attention due to their simple, eco-friendly, and excellent biocompatible traits. Moreover, bio-QDs could not be replaced by chemically fabricated QDs in many fields.

Continuous degradation of ciprofloxacin in a manganese redox cycling system driven by Pseudomonas putida MnB-1.

Ciprofloxacin (CIP), as an extensively used antibiotic, has been widely detected at a high level in the environment and has raised environmental pollution concerns. Thus, efficient and cost-effective methods for CIP degradation are highly desired. Biologically produced manganese oxides (BioMnO) offer a promising perspective for CIP degradation because of their catalytic reactivity and cost-effectiveness.

Directed Biofabrication of Nanoparticles through Regulating Extracellular Electron Transfer.

Biofabrication of nanomaterials is currently constrained by a low production efficiency and poor controllability on product quality compared to chemical synthetic routes. In this work, we show an attractive new biosynthesis system to break these limitations. A directed production of selenium-containing nanoparticles in Shewanella oneidensis MR-1 cells, with fine-tuned composition and subcellular synthetic location, was achieved by modifying the extracellular electron transfer chain.

Spectral insights into the transformation and distribution of CdSe quantum dots in microorganisms during food-chain transport.

The discharge of engineered nanomaterials (ENMs) into environment is raising widespread concern not only due to their direction bio-toxicity but also their bio-concentration and bio-magnification through food web. However, the transformation and distribution of ENMs during food-chain transport are poorly understood, due to lack of accurate, reliable analytical methods. In this study, by using a suite of advanced spectrum techniques, we successfully tracked the distribution and biotransformation dynamics of CdSe quantum dots (QDs) during their transport from Shewanella onedensis to Caenorchabditis elegans in predation.

Fluorescence dynamics of the biosynthesized CdSe quantum dots in Candida utilis.

Organisms served as factories of bio-assembly of nanoparticles attracted a lot of attentions due to the safe, economic and environmental-benignity traits, especially the fabrication of the super fluorescence properties quantum dots (QDs). However, information about the developmental dynamics of QDs in living organisms is still lacking. In this work, we synthesized cadmium-selenium (CdSe) QDs in Candida utilis WSH02-08, and then tracked and quantitatively characterized the developmental dynamics (photoactivation, photostable and photobleaching processes) of bio-QDs by translating fluorescence microscopy movies into visual quantitative curve.