scholarly journals A Bimodal Fluorescence-Raman Probe for Cellular Imaging

Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1699
Author(s):  
Jiarun Lin ◽  
Marcus E. Graziotto ◽  
Peter A. Lay ◽  
Elizabeth J. New

Biochemical changes in specific organelles underpin cellular function, and studying these changes is crucial to understand health and disease. Fluorescent probes have become important biosensing and imaging tools as they can be targeted to specific organelles and can detect changes in their chemical environment. However, the sensing capacity of fluorescent probes is highly specific and is often limited to a single analyte of interest. A novel approach to imaging organelles is to combine fluorescent sensors with vibrational spectroscopic imaging techniques; the latter provides a comprehensive map of the relative biochemical distributions throughout the cell to gain a more complete picture of the biochemistry of organelles. We have developed NpCN1, a bimodal fluorescence-Raman probe targeted to the lipid droplets, incorporating a nitrile as a Raman tag. NpCN1 was successfully used to image lipid droplets in 3T3-L1 cells in both fluorescence and Raman modalities, reporting on the chemical composition and distribution of the lipid droplets in the cells.

2021 ◽  
Vol 161 ◽  
pp. 113186
Author(s):  
Clíssia Barboza da Silva ◽  
Vitor de Jesus Martins Bianchini ◽  
André Dantas de Medeiros ◽  
Maria Heloisa Duarte de Moraes ◽  
Agide Gimenez Marassi ◽  
...  

2013 ◽  
Vol 13 (15) ◽  
pp. 7875-7894 ◽  
Author(s):  
I. El Haddad ◽  
B. D'Anna ◽  
B. Temime-Roussel ◽  
M. Nicolas ◽  
A. Boreave ◽  
...  

Abstract. As part of the FORMES summer 2008 experiment, an Aerodyne compact time-of-flight aerosol mass spectrometer (cToF-AMS) was deployed at an urban background site in Marseille to investigate the sources and aging of organic aerosols (OA). France's second largest city and the largest port in the Mediterranean, Marseille, provides a locale that is influenced by significant urban industrialized emissions and an active photochemistry with very high ozone concentrations. Particle mass spectra were analyzed by positive matrix factorization (PMF2) and the results were in very good agreement with previous apportionments obtained using a chemical mass balance (CMB) approach coupled to organic markers and metals (El Haddad et al., 2011a). AMS/PMF2 was able to identify for the first time, to the best of our knowledge, the organic aerosol emitted by industrial processes. Even with significant industries in the region, industrial OA was estimated to contribute only ~ 5% of the total OA mass. Both source apportionment techniques suggest that oxygenated OA (OOA) constitutes the major fraction, contributing ~ 80% of OA mass. A novel approach combining AMS/PMF2 data with 14C measurements was applied to identify and quantify the fossil and non-fossil precursors of this fraction and to explicitly assess the related uncertainties. Results show with high statistical confidence that, despite extensive urban and industrial emissions, OOA is overwhelmingly non-fossil, formed via the oxidation of biogenic precursors, including monoterpenes. AMS/PMF2 results strongly suggest that the variability observed in the OOA chemical composition is mainly driven in our case by the aerosol photochemical age. This paper presents the impact of photochemistry on the increase of OOA oxygenation levels, formation of humic-like substances (HULIS) and the evolution of α-pinene SOA (secondary OA) components.


1988 ◽  
Vol 91 (1) ◽  
pp. 5-11
Author(s):  
J.B. Rattner ◽  
D.P. Bazett-Jones

Specific antibody labelling indicates that phosphoproteins are present at microtubule-organizing centres, including the centrosome. We have employed electron spectroscopic imaging techniques that permit high-resolution elemental analysis of thin sections of intact cells to investigate the precise distribution of phosphorus and therefore phosphoproteins at the centrosome of Indian muntjac cells. We report that these proteins are localized to both the pericentriolar matrix and the centriole. The matrix contains an abundance of phosphorus and is associated with microtubule elements. Within the mature centriole, major structures including the nine triplet blades and linking elements that connect adjacent blades are composed of phosphorylated proteins. In addition, phosphoproteins are abundant at the ends of the centriole, at the interface between the centriole lumen and the pericentriolar environment. From these observations we suggest that phosphoproteins may play both a structural and a functional role within the centrosome region.


2021 ◽  
Author(s):  
Yao Lulu Xing ◽  
Bernard H.A. Chuang ◽  
Jasmine Poh ◽  
Kaveh Moradi ◽  
Stanislaw Mitew ◽  
...  

Approaches to investigate adult oligodendrocyte progenitor cells (OPCs) by targeted cell ablation in the rodent central nervous system have been limited by methodological challenges resulting in only partial and transient OPC depletion. We have developed a novel pharmacogenetic model of conditional OPC ablation, resulting in the elimination of 99.7% of all OPCs throughout the brain. By combining recombinase-based transgenic and viral strategies for targeting of OPCs and ventricular-subventricular zone (V-SVZ)-derived neural precursor cells (NPCs), we found that new PDGFRα-expressing cells born in the V-SVZ repopulated the OPC-deficient brain starting 12 days after OPC ablation. Our data reveal that OPC depletion induces V-SVZ-derived NPCs to generate vast numbers of PDGFRα+/NG2+ cells with the capacity to migrate and proliferate extensively throughout the dorsal anterior forebrain. Further application of this novel approach to ablate OPCs will advance knowledge of the function of both OPCs and oligodendrogenic NPCs in health and disease.


2020 ◽  
Vol 180 ◽  
pp. 108502
Author(s):  
Kang-Nan Wang ◽  
Xiang-Jun Peng ◽  
Yi Li ◽  
Hai-Tao Tang ◽  
Ying-Ming Pan ◽  
...  

2020 ◽  
Vol 8 ◽  
Author(s):  
Ting Feng ◽  
Yejing Xie ◽  
Weiya Xie ◽  
Dean Ta ◽  
Qian Cheng

Photoacoustic (PA) signal analysis based on ultrasonic wave detection can provide both high-sensitivity optical contrast information and micro-architectural information which is highly related with the chemical composition of tissue. In this study, the feasibility assessment of bone composition assessment was investigated using the multi-wavelength PA analysis (MWPA) method which could reflect the molecular information. By illuminating a bone specimen using a laser light with wavelength over an optical spectrum ranging from 680 to 950 nm, the optical absorption spectrum of the bone was acquired. Then, with the optical absorption spectra of all optical absorption chemical components in the known bone, a spectral unmixing procedure was performed to quantitatively assess the relative content of each chemical component. The experimental results from rabbit bones show that MWPA method can be used to assess chemical components related to bone metabolism. Our study confirmed that PA technique can be used as a novel bone diagnostic technique by providing new information about the quantity of bone and identifying biomarkers of bone that can improve the current diagnostic imaging techniques.


2017 ◽  
Vol 14 (127) ◽  
pp. 20160992 ◽  
Author(s):  
B. Zeller-Plumhoff ◽  
T. Roose ◽  
G. F. Clough ◽  
P. Schneider

The supply of oxygen in sufficient quantity is vital for the correct functioning of all organs in the human body, in particular for skeletal muscle during exercise. Disease is often associated with both an inhibition of the microvascular supply capability and is thought to relate to changes in the structure of blood vessel networks. Different methods exist to investigate the influence of the microvascular structure on tissue oxygenation, varying over a range of application areas, i.e. biological in vivo and in vitro experiments, imaging and mathematical modelling. Ideally, all of these methods should be combined within the same framework in order to fully understand the processes involved. This review discusses the mathematical models of skeletal muscle oxygenation currently available that are based upon images taken of the muscle microvasculature in vivo and ex vivo . Imaging systems suitable for capturing the blood vessel networks are discussed and respective contrasting methods presented. The review further informs the association between anatomical characteristics in health and disease. With this review we give the reader a tool to understand and establish the workflow of developing an image-based model of skeletal muscle oxygenation. Finally, we give an outlook for improvements needed for measurements and imaging techniques to adequately investigate the microvascular capability for oxygen exchange.


2017 ◽  
Vol 1 (6) ◽  
pp. 407-416 ◽  
Author(s):  
Cesar Nombela-Arrieta ◽  
Markus G. Manz

Abstract Bone marrow (BM) constitutes one of the largest organs in mice and humans, continuously generating, in a highly regulated manner, red blood cells, platelets, and white blood cells that together form the majority of cells of the body. In this review, we provide a quantitative overview of BM cellular composition, we summarize emerging knowledge on its structural organization and cellular niches, and we argue for the need of multidimensional approaches such as recently developed imaging techniques to uncover the complex spatial logic that underlies BM function in health and disease.


Author(s):  
Moirangthem Kiran Singh ◽  
Linda J Kenney

ABSTRACT Recent advances in super-resolution imaging techniques, together with new fluorescent probes have enhanced our understanding of bacterial pathogenesis and their interplay within the host. In this review, we provide an overview of what these techniques have taught us about the bacterial lifestyle, the nucleoid organization, its complex protein secretion systems, as well as the secreted virulence factors.


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