Search results for "Microscopy"
showing 10 items of 3390 documents
First multiphoton tomography of brain in man
2016
We report on the first two-photon in vivo brain tissue imaging study in man. High resolution in vivo histology by multiphoton tomography (MPT) including two-photon FLIM was performed in the operation theatre during neurosurgery to evaluate the feasibility to detect label-free tumor borders with subcellular resolution. This feasibility study demonstrates, that MPT has the potential to identify tumor borders on a cellular level in nearly real-time.
Carbon Nanodots as Functional Excipient to Develop Highly Stable and Smart PLGA Nanoparticles Useful in Cancer Theranostics
2020
Theranostic systems have attracted considerable attention for their multifunctional approach to cancer. Among these, carbon nanodots (CDs) emerged as luminescent nanomaterials due to their exceptional chemical properties, synthetic ease, biocompatibility, and for their photothermal and fluorescent properties useful in cancer photothermal therapy. However, premature renal excretion due to the small size of these particles limits their biomedical application. To overcome these limitations, here, hybrid poly(lactic-co-glycolic acid) (PLGA-CDs) nanoparticles with suitable size distribution and stability have been developed. CDs were decisive in the preparation of polymeric nanoparticles, not on…
Highly Homogeneous Biotinylated Carbon Nanodots: Red-Emitting Nanoheaters as Theranostic Agents toward Precision Cancer Medicine
2019
Very recent red-emissive carbon nanodots (CDs) have shown potential as near-infrared converting tools to produce local heat useful in cancer theranostics. Besides, CDs seem very appealing for clinical applications combining hyperthermia, imaging, and drug delivery in a single platform capable of selectively targeting cancer cells. However, CDs still suffer from dramatic dot-to-dot variability issues such that a rational design of their structural, optical, and chemical characteristics for medical applications has been impossible so far. Herein, we report for the first time a simple and highly controllable layer-by-layer synthesis of biotin-decorated CDs with monodisperse size distribution, …
Fluorescence and spin properties of defects in single digit nanodiamonds
2009
International audience; This article reports stable photoluminescence and high-contrast optically detected electron spin resonance (ODESR) from single nitrogen-vacancy (NV) defect centers created within ultrasmall, disperse nanodiamonds of radius less than 4 nm. Unexpectedly, the efficiency for the production of NV fluorescent defects by electron irradiation is found to be independent of the size of the nanocrystals. Fluorescence lifetime imaging shows lifetimes with a mean value of around 17 ns, only slightly longer than the bulk value of the defects. After proper surface cleaning, the dephasing times of the electron spin resonance in the nanocrystals approach values of some microseconds, …
Gold(I)-Coumarin-Caffeine-Based Complexes as New Potential Anti-Inflammatory and Anticancer Trackable Agents.
2018
Three new gold(I)-coumarin-based trackable therapeutic complexes and two non-trackable analogues have been synthesised and fully characterised. They all display anti-proliferative properties on several types of cancer cell lines, including those of colon, breast, and prostate. Two complexes displayed significant anti-inflammatory effects; one displayed pro-inflammatory behaviour; this highlights the impact of the position of the fluorophore on the caffeine scaffold. Additionally, the three coumarin derivatives could be visualised in vitro by two-photon microscopy.
WITHDRAWN: Measurement of beam focus quality in biomedical nuclear microscopy.
2009
This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.
The impact of dehydration rate on the production and cellular location of reactive oxygen species in an aquatic moss.
2012
† Background and Aims The aquatic moss Fontinalis antipyretica requires a slow rate of dehydration to survive a desiccation event. The present work examined whether differences in the dehydration rate resulted in corresponding differences in the production of reactive oxygen species (ROS) and therefore in the amount of cell damage. † Methods Intracellular ROS production by the aquatic moss was assessed with confocal laser microscopy and the ROS-specific chemical probe 2,7-dichlorodihydrofluorescein diacetate. The production of hydrogen peroxide was also quantified and its cellular location was assessed. † Key Results The rehydration of slowly dried cells was associated with lower ROS produc…
The coffee-machine bacteriome: biodiversity and colonisation of the wasted coffee tray leach
2015
AbstractMicrobial communities are ubiquitous in both natural and artificial environments. However, microbial diversity is usually reduced under strong selection pressures, such as those present in habitats rich in recalcitrant or toxic compounds displaying antimicrobial properties. Caffeine is a natural alkaloid present in coffee, tea and soft drinks with well-known antibacterial properties. Here we present the first systematic analysis of coffee machine-associated bacteria. We sampled the coffee waste reservoir of ten different Nespresso machines and conducted a dynamic monitoring of the colonization process in a new machine. Our results reveal the existence of a varied bacterial community…
Small-sized granules of biphasic bone substitutes support fast implant bed vascularization
2015
The present study investigated the influence of granule size of 2 biphasic bone substitutes (BoneCeramic® 400-700 μm and 500-1000 μm) on the induction of multinucleated giant cells (MNGCs) and implant bed vascularization in a subcutaneous implantation model in rats. Furthermore, degradation mechanisms and particle phagocytosis of both materials were examined by transmission electron microscopy (TEM). Both granule types induced tissue reactions involving primarily mononuclear cells and only small numbers of MNGCs. Higher numbers of MNGCs were detected in the group with small granules starting on day 30, while higher vascularization was observed only at day 10 in this group. TEM analysis reve…
Of Thiols and Disulfides: Methods for Chemoselective Formation of Asymmetric Disulfides in Synthetic Peptides and Polymers.
2018
In protein or peptide chemistry, thiols are frequently chosen as a chemical entity for chemoselective modification reactions. Although it is a well-established methodology to address cysteines and homocysteines in aqueous media to form S-C bonds, possibilities for the chemoselective formation of asymmetric disulfides have been less approached. Focusing on bioreversibility in conjugation chemistry, the formation of disulfide bonds is highly desirable for the attachment of thiol-containing bioactive agents to proteins or in cross-linking reactions, because disulfide bonds can combine stability in blood with degradability inside cells. In this Concept article, recent approaches in the field of…