keyword
MENU ▼
Read by QxMD icon Read
search

multiphoton

keyword
https://www.readbyqxmd.com/read/28911733/time-lapsed-large-volume-high-resolution-intravital-imaging-for-tissue-wide-analysis-of-single-cell-dynamics
#1
David Entenberg, Jessica M Pastoriza, Maja H Oktay, Sonia Voiculescu, Yarong Wang, Maria Soledad Sosa, Julio Aguirre-Ghiso, John Condeelis
Pathologists rely on microscopy to diagnose disease states in tissues and organs. They utilize both high-resolution, high-magnification images to interpret the staining and morphology of individual cells, as well as low-magnification overviews to give context and location to these cells. Intravital imaging is a powerful technique for studying cells and tissues in their native, live environment and can yield sub-cellular resolution images similar to those used by pathologists. However, technical limitations prevent the straightforward acquisition of low-magnification images during intravital imaging, and they are hence not typically captured...
September 1, 2017: Methods: a Companion to Methods in Enzymology
https://www.readbyqxmd.com/read/28902016/raman-microscopy-a-noninvasive-method-to-visualize-the-localizations-of-biomolecules-in-the-cornea
#2
Yuichi Kaji, Toshihiro Akiyama, Hiroki Segawa, Tetsuro Oshika, Hideaki Kano
PURPOSE: In vivo and in situ visualization of biomolecules without pretreatment will be important for diagnosis and treatment of ocular disorders in the future. Recently, multiphoton microscopy, based on the nonlinear interactions between molecules and photons, has been applied to reveal the localizations of various molecules in tissues. We aimed to use multimodal multiphoton microscopy to visualize the localizations of specific biomolecules in rat corneas. METHODS: Multiphoton images of the corneas were obtained from nonlinear signals of coherent anti-Stokes Raman scattering, third-order sum frequency generation, and second-harmonic generation...
September 7, 2017: Cornea
https://www.readbyqxmd.com/read/28894365/photothermal-ablation-of-inflammatory-breast-cancer-tumor-emboli-using-plasmonic-gold-nanostars
#3
Bridget M Crawford, Ronnie L Shammas, Andrew M Fales, David A Brown, Scott T Hollenbeck, Tuan Vo-Dinh, Gayathri R Devi
Inflammatory breast cancer (IBC) is rare, but it is the most aggressive subtype of breast cancer. IBC has a unique presentation of diffuse tumor cell clusters called tumor emboli in the dermis of the chest wall that block lymph vessels causing a painful, erythematous, and edematous breast. Lack of effective therapeutic treatments has caused mortality rates of this cancer to reach 20%-30% in case of women with stage III-IV disease. Plasmonic nanoparticles, via photothermal ablation, are emerging as lead candidates in next-generation cancer treatment for site-specific cell death...
2017: International Journal of Nanomedicine
https://www.readbyqxmd.com/read/28890492/a-quantitative-analysis-of-an-oil-component-in-an-emulsion-by-multiphoton-ionization-mass-spectrometry
#4
Hirofumi Fukaya, Tomohiro Uchimura
The first quantitative analysis of an oil component in an emulsion was achieved by multiphoton ionization time-of-flight mass spectrometry (MPI-TOFMS). An oil-in-water (O/W) emulsion was prepared. Styrene (0 - 5000 ng μL(-1)) and Triton X-100 were used as the oil phase and the disperser, respectively. Toluene was employed as an internal standard. We obtained a series of mass spectra, and then constructed the time profiles for styrene and toluene. As a result, we found several spikes from both time profiles when measuring emulsions with higher concentrations of styrene...
2017: Analytical Sciences: the International Journal of the Japan Society for Analytical Chemistry
https://www.readbyqxmd.com/read/28888430/vacuum-facilitated-infusion-of-bioactives-into-yeast-microcarriers-evaluation-of-a-novel-encapsulation-approach
#5
Stephen Young, Sharleen Dea, Nitin Nitin
Encapsulation into yeast microcarriers provides an appealing alternative to biomimetic systems by employing natural, pre-formed vehicles for the stabilization and delivery of bioactives compounds. However, current (diffusion-limited) methods of encapsulation using yeast require long time scales and heating which lead to poor encapsulation efficiencies and yields. This study evaluates the usage of vacuum infusion to encapsulate two model bioactives, curcumin and fisetin, into yeast and yeast cell wall particles and the physical parameters, e...
October 2017: Food Research International
https://www.readbyqxmd.com/read/28863653/sine-wave-gating-silicon-single-photon-detectors-for-multiphoton-entanglement-experiments
#6
Nan Zhou, Wen-Hao Jiang, Luo-Kan Chen, Yu-Qiang Fang, Zheng-Da Li, Hao Liang, Yu-Ao Chen, Jun Zhang, Jian-Wei Pan
Silicon single-photon detectors (SPDs) are the key devices for detecting single photons in the visible wavelength range. Here we present high detection efficiency silicon SPDs dedicated to the generation of multiphoton entanglement based on the technique of high-frequency sine wave gating. The silicon single-photon avalanche diode components are acquired by disassembling 6 commercial single-photon counting modules (SPCMs). Using the new quenching electronics, the average detection efficiency of SPDs is increased from 68...
August 2017: Review of Scientific Instruments
https://www.readbyqxmd.com/read/28862343/cellular-detection-of-g-quadruplexes-by-optical-imaging-methods
#7
Souheila Amor, Sunny Y Yang, Judy M Y Wong, David Monchaud
G-quadruplexes (G4s) are higher-order nucleic acid structures that fold from guanine (G)-rich DNA and RNA strands. This field of research gains traction as a major chemical biology area since it aims at uncovering many key cellular mechanisms in which quadruplexes are involved. The wealth of knowledge acquired over the past three decades strongly supports pivotal roles of G4 in the regulation of gene expression at both transcriptional (DNA quadruplexes) and translational levels (RNA quadruplexes). Recent biochemical discoveries uncovered myriad of additional G4 actions: from chromosomal stability to the firing of replication origins, from telomere homeostasis to functional dysregulations underlying genetic diseases (including cancers and neurodegeneration)...
September 1, 2017: Current Protocols in Cell Biology
https://www.readbyqxmd.com/read/28858435/in-vivo-multiphoton-microscopy-using-a-handheld-scanner-with-lateral-and-axial-motion-compensation
#8
Ben Sherlock, Sean C Warren, Yuriy Alexandrov, Fei Yu, James Stone, Jonathan Knight, Mark A A Neil, Carl Paterson, Paul M W French, Chris Dunsby
This paper reports a handheld multiphoton fluorescence microscope designed for clinical imaging that incorporates axial motion compensation and lateral image stabilization. Spectral domain optical coherence tomography is employed to track the axial position of the skin surface, and lateral motion compensation is realised by imaging the speckle pattern arising from the optical coherence tomography beam illuminating the sample. Our system is able to correct lateral sample velocities of up to ~65 μm s(-1) . Combined with the use of negative curvature microstructured optical fibre to deliver tunable ultrafast radiation to the handheld multiphoton scanner without the need of a dispersion compensation unit, this instrument has potential for a range of clinical applications...
August 31, 2017: Journal of Biophotonics
https://www.readbyqxmd.com/read/28856032/optimizing-pulse-compressibility-in-completely-all-fibered-ytterbium-chirped-pulse-amplifiers-for-in-vivo-two-photon-laser-scanning-microscopy
#9
A Fernández, L Grüner-Nielsen, M Andreana, M Stadler, S Kirchberger, C Sturtzel, M Distel, L Zhu, W Kautek, R Leitgeb, A Baltuska, K Jespersen, A Verhoef
A simple and completely all-fiber Yb chirped pulse amplifier that uses a dispersion matched fiber stretcher and a spliced-on hollow core photonic bandgap fiber compressor is applied in nonlinear optical microscopy. This stretching-compression approach improves compressibility and helps to maximize the fluorescence signal in two-photon laser scanning microscopy as compared with approaches that use standard single mode fibers as stretcher. We also show that in femtosecond all-fiber systems, compensation of higher order dispersion terms is relevant even for pulses with relatively narrow bandwidths for applications relying on nonlinear optical effects...
August 1, 2017: Biomedical Optics Express
https://www.readbyqxmd.com/read/28846081/microglia-turnover-with-aging-and-in-an-alzheimer-s-model-via-long-term-in-vivo-single-cell-imaging
#10
Petra Füger, Jasmin K Hefendehl, Karthik Veeraraghavalu, Ann-Christin Wendeln, Christine Schlosser, Ulrike Obermüller, Bettina M Wegenast-Braun, Jonas J Neher, Peter Martus, Shinichi Kohsaka, Martin Thunemann, Robert Feil, Sangram S Sisodia, Angelos Skodras, Mathias Jucker
To clarify the role of microglia in brain homeostasis and disease, an understanding of their maintenance, proliferation and turnover is essential. The lifespan of brain microglia, however, remains uncertain, and reflects confounding factors in earlier assessments that were largely indirect. We genetically labeled single resident microglia in living mice and then used multiphoton microscopy to monitor these cells over time. Under homeostatic conditions, we found that neocortical resident microglia were long-lived, with a median lifetime of well over 15 months; thus, approximately half of these cells survive the entire mouse lifespan...
August 28, 2017: Nature Neuroscience
https://www.readbyqxmd.com/read/28843556/a-new-technique-for-probing-chirality-via-photoelectron-circular-dichroism
#11
J Miles, D Fernandes, A Young, C M M Bond, S W Crane, O Ghafur, D Townsend, J Sá, J B Greenwood
We present a proof-of-principle approach for discriminating chiral enantiomers based on the phenomenon of multiphoton photoelectron circular dichroism. A novel stereo detection setup was used to measure the number of photoelectrons emitted from chiral molecules in directions parallel or anti-parallel to the propagation of the ionising femtosecond laser pulses. In this study, we show how these asymmetries in the ketones camphor and fenchone depend upon the ellipticity of the laser pulses and the enantiomeric excess of the sample...
September 1, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28839271/smartscope2-simultaneous-imaging-and-reconstruction-of-neuronal-morphology
#12
Brian Long, Zhi Zhou, Ali Cetin, Jonathan Ting, Ryder Gwinn, Bosiljka Tasic, Tanya Daigle, Ed Lein, Hongkui Zeng, Peter Saggau, Michael Hawrylycz, Hanchuan Peng
Quantitative analysis of neuronal morphology is critical in cell type classification and for deciphering how structure gives rise to function in the brain. Most current approaches to imaging and tracing neuronal 3D morphology are data intensive. We introduce SmartScope2, the first open source, automated neuron reconstruction machine integrating online image analysis with automated multiphoton imaging. SmartScope2 takes advantage of a neuron's sparse morphology to improve imaging speed and reduce image data stored, transferred and analyzed...
August 24, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28838859/transmural-variation-in-elastin-fiber-orientation-distribution-in-the-arterial-wall
#13
Xunjie Yu, Yunjie Wang, Yanhang Zhang
The complex three-dimensional elastin network is a major load-bearing extracellular matrix (ECM) component of an artery. Despite the reported anisotropic behavior of arterial elastin network, it is usually treated as an isotropic material in constitutive models. Our recent multiphoton microscopy study reported a relatively uniform elastin fiber orientation distribution in porcine thoracic aorta when imaging from the intima side (Chow et al., 2014). However it is questionable whether the fiber orientation distribution obtained from a small depth is representative of the elastin network structure in the arterial wall, especially when developing structure-based constitutive models...
August 5, 2017: Journal of the Mechanical Behavior of Biomedical Materials
https://www.readbyqxmd.com/read/28838234/structural-characterization-of-intact-glycoconjugates-by-tandem-mass-spectrometry-using-electron-induced-dissociation
#14
Y L Elaine Wong, Xiangfeng Chen, Ri Wu, Y L Winnie Hung, T-W Dominic Chan
Characterizing the structures of glycoconjungates is important because of glycan heterogeneity and structural complexity of aglycon. The presence of relatively weak glycosidic linkages leads to preferential cleavages that limit the acquisition of structural information under typical mass spectrometry dissociation conditions, such as collision-induced dissociation (CID) and infrared multiphoton dissociation. In this paper, we explored the dissociation behaviors of different members of glycoconjugates, including glycopeptides, glycoalkaloids, and glycolipids, under electron-induced dissociation (EID) conditions...
September 7, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28836304/impaired-microglia-process-dynamics-post-stroke-are-specific-to-sites-of-secondary-neurodegeneration
#15
Murielle G Kluge, Laura Kracht, Mahmoud Abdolhoseini, Lin Kooi Ong, Sarah J Johnson, Michael Nilsson, Frederick R Walker
Stroke induces tissue death both at the site of infarction and at secondary sites connected to the primary infarction. This latter process has been referred to as secondary neurodegeneration (SND). Using predominantly fixed tissue analyses, microglia have been implicated in regulating the initial response at both damage sites post-stroke. In this study, we used acute slice based multiphoton imaging, to investigate microglia dynamic process movement in mice 14 days after a photothrombotic stroke. We evaluated the baseline motility and process responses to locally induced laser damage in both the peri-infarct (PI) territory and the ipsilateral thalamus, a major site of post-stroke SND...
August 24, 2017: Glia
https://www.readbyqxmd.com/read/28827843/the-passive-biomechanics-of-human-pelvic-collecting-lymphatic-vessels
#16
Dimitrios Athanasiou, Lowell T Edgar, Mohammad Jafarnejad, Katherine Nixon, Delfim Duarte, Edwin D Hawkins, Samira Jamalian, Paula Cunnea, Cristina Lo Celso, Shunichi Kobayashi, Christina Fotopoulou, James E Moore
The lymphatic system has a major significance in the metastatic pathways in women's cancers. Lymphatic pumping depends on both extrinsic and intrinsic mechanisms, and the mechanical behavior of lymphatic vessels regulates the function of the system. However, data on the mechanical properties and function of human lymphatics are lacking. Our aim is to characterize, for the first time, the passive biomechanical behavior of human collecting lymphatic vessels removed at pelvic lymph node dissection during primary debulking surgeries for epithelial ovarian cancer...
2017: PloS One
https://www.readbyqxmd.com/read/28815554/severe-disruption-and-disorganization-of-dermal-collagen-fibrils-in-early-striae-gravidarum
#17
F Wang, K Calderone, T T Do, N R Smith, Y R Helfrich, T R B Johnson, S Kang, J J Voorhees, G J Fisher
BACKGROUND: Striae gravidarum (SG), or stretch marks of pregnancy, begin as erythematous streaks, and mature into hypopigmented atrophic bands. OBJECTIVES: To investigate molecular alterations that may promote atrophy of SG, we investigated dermal type I collagen fibrils, which provide human skin with support. METHODS: We obtained skin samples of recently developed, erythematous abdominal SG from pregnant women. To examine the organization of collagen fibrils, second-harmonic generation imaging was performed using multiphoton microscopy...
August 17, 2017: British Journal of Dermatology
https://www.readbyqxmd.com/read/28810820/quantitative-label-free-evaluation-of-tissue-engineered-skeletal-muscle-through-multiphoton-microscopy
#18
Brian C Syverud, Mary-Ann Mycek, Lisa Marie Larkin
The lack of tools for assessing engineered tissue viability and function in a non-invasive manner is a major regulatory and translational challenge facing tissue engineers. Label-free, nonlinear optical molecular imaging (OMI) has utilized endogenous nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD) fluorescence to indicate metabolic activity. Similarly, second harmonic generation (SHG) signals from myosin and collagen can measure overall muscle structural integrity and function...
August 16, 2017: Tissue Engineering. Part C, Methods
https://www.readbyqxmd.com/read/28809529/multiphoton-fabrication-of-fibronectin-functionalized-protein-micropatterns-stiffness-induced-maturation-of-cell-matrix-adhesions-in-human-mesenchymal-stem-cells
#19
Jiaoni Ma, Chuenwai Li, Nan Huang, Xinna Wang, Minghui Tong, Alfonso H W Ngan, Barbara P Chan
Cell-matrix adhesions are important structures governing the interactions between cells and their microenvironment at the cell-matrix interface. The focal complex (FC) and focal adhesion (FA) have been substantially investigated in conventional planar culture systems using fibroblasts as an in vitro model. However, the formation of more mature types of cell-matrix adhesion in human mesenchymal stem cells (hMSCs), including fibrillar adhesion (FBA) and 3D matrix adhesion (3DMA), have not been fully elucidated...
August 24, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28805825/the-processing-and-heterostructuring-of-silk-with%C3%A2-light
#20
Mehra S Sidhu, Bhupesh Kumar, Kamal P Singh
Spider silk is a tough, elastic and lightweight biomaterial, although there is a lack of tools available for non-invasive processing of silk structures. Here we show that nonlinear multiphoton interactions of silk with few-cycle femtosecond pulses allow the processing and heterostructuring of the material in ambient air. Two qualitatively different responses, bulging by multiphoton absorption and plasma-assisted ablation, are observed for low- and high-peak intensities, respectively. Plasma ablation allows us to make localized nanocuts, microrods, nanotips and periodic patterns with minimal damage while preserving molecular structure...
September 2017: Nature Materials
keyword
keyword
15078
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"