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https://www.readbyqxmd.com/read/28634334/image-guided-transplantation-of-single-cells-in-the-bone-marrow-of-live-animals
#1
Raphaël Turcotte, Clemens Alt, Judith M Runnels, Kyoko Ito, Juwell W Wu, Walid Zaher, Luke J Mortensen, Lev Silberstein, Daniel C Côté, Andrew L Kung, Keisuke Ito, Charles P Lin
Transplantation of a single hematopoietic stem cell is an important method for its functional characterization, but the standard transplantation protocol relies on cell homing to the bone marrow after intravenous injection. Here, we present a method to transplant single cells directly into the bone marrow of live mice. We developed an optical platform that integrates a multiphoton microscope with a laser ablation unit for microsurgery and an optical tweezer for cell micromanipulation. These tools allow image-guided single cell transplantation with high spatial control...
June 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28630067/sipa-activation-of-caspase-3-is-a-decisive-mediator-of-host-cell-survival-at-early-stages-of-salmonella-typhimurium-infection
#2
Anne McIntosh, Lynsey M Meikle, Michael Ormsby, Beth A McCormick, John M Christie, James M Brewer, Mark Roberts, Daniel M Wall
Salmonella invasion protein A (SipA) is a dual function effector protein that plays roles in both actin polymerization and caspase-3 activation in intestinal epithelial cells. To date its function in other cell types has remained largely unknown despite its expression in multiple cell types and its extracellular secretion during infection. Here we show that in macrophages SipA induces increased caspase-3 activation early in infection. This activation required a threshold level of SipA linked to multiplicity of infection and may be a limiting factor controlling bacterial numbers in infected macrophages...
June 19, 2017: Infection and Immunity
https://www.readbyqxmd.com/read/28628128/adaptive-optics-improves-multiphoton-super-resolution-imaging
#3
Wei Zheng, Yicong Wu, Peter Winter, Robert Fischer, Damian Dalle Nogare, Amy Hong, Chad McCormick, Ryan Christensen, William P Dempsey, Don B Arnold, Joshua Zimmerberg, Ajay Chitnis, James Sellers, Clare Waterman, Hari Shroff
We improve multiphoton structured illumination microscopy using a nonlinear guide star to determine optical aberrations and a deformable mirror to correct them. We demonstrate our method on bead phantoms, cells in collagen gels, nematode larvae and embryos, Drosophila brain, and zebrafish embryos. Peak intensity is increased (up to 40-fold) and resolution recovered (up to 176 ± 10 nm laterally, 729 ± 39 nm axially) at depths ∼250 μm from the coverslip surface.
June 19, 2017: Nature Methods
https://www.readbyqxmd.com/read/28625344/confined-photonic-mode-propagation-observed-in-photoemission-electron-microscopy
#4
Theodore Stenmark, R C Word, R Könenkamp
Using photoemission electron microscopy (PEEM) we present a comparative analysis of the wavelength dependence of propagating fields in a simple optical slab waveguide and a thin film photonic crystal W1-type waveguide. We utilize an interferometric imaging approach for light in the near-ultraviolet regime where a 2-photon process is required to produce photoelectron emission. The typical spatial resolution in these experiments is < 30nm. Electromagnetic theory and finite element simulations are shown to be in good agreement with the experimental observations...
June 13, 2017: Ultramicroscopy
https://www.readbyqxmd.com/read/28624539/polarization-resolved-second-harmonic-microscopy
#5
REVIEW
Nirmal Mazumder, Gitanjal Deka, Wei-Wen Wu, Ankur Gogoi, Guan-Yu Zhuo, Fu-Jen Kao
Second harmonic (SH) microscopy has proven to be a powerful imaging modality over the past years due to its intrinsic advantages as a multiphoton process with endogenous contrast specificity, which allows pinhole-less optical sectioning, non-invasive observation, deep tissue penetration, and the possibility of easier signal detection at visible wavelengths. Depending on the relative orientation between the polarization of the incoming light and the second-order susceptibility of non-centrosymmetric structures, SH microscopy provides the unique capacity to probe the absolute molecular structure of a broad variety of biological tissues without the necessity for additional labeling...
June 14, 2017: Methods: a Companion to Methods in Enzymology
https://www.readbyqxmd.com/read/28598655/efficient-multiphoton-generation-in-waveguide-quantum-electrodynamics
#6
A González-Tudela, V Paulisch, H J Kimble, J I Cirac
Engineering quantum states of light is at the basis of many quantum technologies such as quantum cryptography, teleportation, or metrology among others. Though, single photons can be generated in many scenarios, the efficient and reliable generation of complex single-mode multiphoton states is still a long-standing goal in the field, as current methods either suffer from low fidelities or small probabilities. Here we discuss several protocols which harness the strong and long-range atomic interactions induced by waveguide QED to efficiently load excitations in a collection of atoms, which can then be triggered to produce the desired multiphoton state...
May 26, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28598160/a-double-decarboxylation-in-superfolder-green-fluorescent-protein-leads-to-high-contrast-photoactivation
#7
Joshua D Slocum, Lauren J Webb
A photoactivatable variant of superfolder GFP (GFP) was created by replacing the threonine at position 203 with aspartic acid. Photoactivation by exposure of this mutant to UV light resulted in conversion of the fluorophore from the neutral to the negatively charged form, accompanied by a ~95-fold increase in fluorescence under 488 nm excitation. Mass spectrometry before and after exposure to UV light revealed a change in mass of 88 Da, attributed to the double decarboxylation of Glu 222 and Asp 203. Kinetics studies and non-linear power-dependence of the initial rate of photoconversion indicated that the double decarboxylation occurred via a multiphoton absorption process at 254 nm...
June 9, 2017: Journal of Physical Chemistry Letters
https://www.readbyqxmd.com/read/28596141/delivery-of-cyclodextrin-polymers-to-bacterial-biofilms-an-exploratory-study-using-rhodamine-labelled-cyclodextrins-and-multiphoton-microscopy
#8
Hanna Thomsen, Gábor Benkovics, Éva Fenyvesi, Anne Farewell, Milo Malanga, Marica B Ericson
Cyclodextrin (CD) polymers are interesting nanoparticulate systems for pharmaceutical delivery; however, knowledge regarding their applications towards delivery into complex microbial biofilm structures is so far limited. The challenge is to demonstrate penetration and transport through the biofilm and its exopolysaccharide matrix. The ideal functionalization for penetration into mature biofilms is unexplored. In this paper, we present a novel set of rhodamine labelled βCD-polymers, with different charge moieties, i...
June 6, 2017: International Journal of Pharmaceutics
https://www.readbyqxmd.com/read/28594639/spin-valley-dynamics-of-electrically-driven-ambipolar-carbon-nanotube-quantum-dots
#9
E N Osika, A Chacón, M Lewenstein, B Szafran
An ambipolar n-p double quantum dot defined by potential variation along a semiconducting carbon-nanotube is considered. We focus on the (1e,1h) charge configuration with a single excess electron of the conduction band confined in the n-type dot and a single missing electron in the valence band state of the p-type dot for which lifting of the Pauli blockade of the current was observed in the electric-dipole spin resonance (Laird et al 2013 Nat. Nanotechnol. 8 565). The dynamics of the system driven by periodic electric field is studied with the Floquet theory and the time-dependent configuration interaction method with the single-electron spin-valley-orbitals determined for atomistic tight-binding Hamiltonian...
July 19, 2017: Journal of Physics. Condensed Matter: An Institute of Physics Journal
https://www.readbyqxmd.com/read/28589346/microanatomical-labeling-of-germinal-center-structures-for-flow-cytometry-using-photoactivation
#10
Johanne T Jacobsen, Gabriel D Victora
Germinal centers (GCs) are inducible microanatomical structures required for the generation of high-affinity antibodies. Migration of B and T cells within and into/out of GCs plays a key role in the evolutionary process that underlies affinity maturation, and thus microanatomical location of cells is an important variable when studying GC processes. We describe a protocol in which in situ photoactivation by multiphoton microscopy can be used to add microanatomical information to flow cytometry, allowing for identification and isolation of GC cells based on their location...
2017: Methods in Molecular Biology
https://www.readbyqxmd.com/read/28582908/the-collagen-microstructural-changes-of-rat-menisci-and-tibiofemoral-cartilages-under-the-influence-of-mechanical-loading-an-in-vitro-wear-test-of-whole-joints
#11
Haoliuyang Cai, Zhixiu Hao, Liying Xiao, Chao Wan, Lingying Tong
BACKGROUND: Knee osteoarthritis (OA) is suggested to be induced by multi-factors, and mechanical environment is regarded as a risky factor. OBJECTIVE: To investigate the effect of isolated mechanical factor on cartilage. METHODS: An active wear test system was designed to perform parameters-controlled in vitro wear tests on rat knee joints with specific load magnitude, flexion-extension angle, and movement frequency. Six hind limbs of 9-month-old male Sprague-Dawley rats, with an additional spring on the medial side, were worn by using the custom-designed apparatus...
May 19, 2017: Technology and Health Care: Official Journal of the European Society for Engineering and Medicine
https://www.readbyqxmd.com/read/28580960/rapid-visualization-of-grain-boundaries-in-monolayer-mos2-by-multiphoton-microscopy
#12
Lasse Karvonen, Antti Säynätjoki, Mikko J Huttunen, Anton Autere, Babak Amirsolaimani, Shisheng Li, Robert A Norwood, Nasser Peyghambarian, Harri Lipsanen, Goki Eda, Khanh Kieu, Zhipei Sun
Grain boundaries have a major effect on the physical properties of two-dimensional layered materials. Therefore, it is important to develop simple, fast and sensitive characterization methods to visualize grain boundaries. Conventional Raman and photoluminescence methods have been used for detecting grain boundaries; however, these techniques are better suited for detection of grain boundaries with a large crystal axis rotation between neighbouring grains. Here we show rapid visualization of grain boundaries in chemical vapour deposited monolayer MoS2 samples with multiphoton microscopy...
June 5, 2017: Nature Communications
https://www.readbyqxmd.com/read/28577300/application-of-higher-energy-collisional-dissociation-hcd-to-the-fragmentation-of-new-dota-based-labels-and-n-termini-dota-labeled-peptides
#13
A H El-Khatib, Y He, D Esteban-Fernández, M W Linscheid
DOTA derivatives are applied in quantitative proteomics owing to their ability to react with different functional groups, to harbor lanthanoides and hence their compatibility with molecular and elemental mass spectrometry. The new DOTA derivatives, namely Ln-MeCAT-Click and Ln-DOTA-Dimedone, allow efficient thiol labeling and targeting sulfenation as an important post-translational modification, respectively. Quantitative applications require the investigation of fragmentation behavior of these reagents. Therefore, the fragmentation behavior of Ln-MeCAT-Click and Ln-DOTA-Dimedone was studied using collision-induced dissociation (CID), infrared multiphoton dissociation (IRMPD) and higher-energy collision dissociation (HCD) using different energy levels and the efficiency of reporter ion production was estimated...
June 2, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/28569799/femtosecond-response-of-polyatomic-molecules-to-ultra-intense-hard-x-rays
#14
A Rudenko, L Inhester, K Hanasaki, X Li, S J Robatjazi, B Erk, R Boll, K Toyota, Y Hao, O Vendrell, C Bomme, E Savelyev, B Rudek, L Foucar, S H Southworth, C S Lehmann, B Kraessig, T Marchenko, M Simon, K Ueda, K R Ferguson, M Bucher, T Gorkhover, S Carron, R Alonso-Mori, J E Koglin, J Correa, G J Williams, S Boutet, L Young, C Bostedt, S-K Son, R Santra, D Rolles
X-ray free-electron lasers enable the investigation of the structure and dynamics of diverse systems, including atoms, molecules, nanocrystals and single bioparticles, under extreme conditions. Many imaging applications that target biological systems and complex materials use hard X-ray pulses with extremely high peak intensities (exceeding 10(20) watts per square centimetre). However, fundamental investigations have focused mainly on the individual response of atoms and small molecules using soft X-rays with much lower intensities...
June 1, 2017: Nature
https://www.readbyqxmd.com/read/28558136/multiphoton-direct-laser-writing-and-3d-imaging-of-polymeric-freestanding-architectures-for-cell-colonization
#15
Angelo Accardo, Marie-Charline Blatché, Rémi Courson, Isabelle Loubinoux, Christophe Thibault, Laurent Malaquin, Christophe Vieu
The realization of 3D architectures for the study of cell growth, proliferation, and differentiation is a task of fundamental importance for both technological and biological communities involved in the development of biomimetic cell culture environments. Here we report the fabrication of 3D freestanding scaffolds, realized by multiphoton direct laser writing and seeded with neuroblastoma cells, and their multitechnique characterization using advanced 3D fluorescence imaging approaches. The high accuracy of the fabrication process (≈200 nm) allows a much finer control of the micro- and nanoscale features compared to other 3D printing technologies based on fused deposition modeling, inkjet printing, selective laser sintering, or polyjet technology...
May 30, 2017: Small
https://www.readbyqxmd.com/read/28556967/teriparatide-treatment-improves-bone-defect-healing-via-anabolic-effects-on-new-bone-formation-and-non-anabolic-effects-on-inhibition-of-mast-cells-in-a-murine-cranial-window-model
#16
Longze Zhang, Tao Wang, Martin Chang, Claire Kaiser, Jason D Kim, Tianyu Wu, Xiaoyi Cao, Xinping Zhang, Edward M Schwarz
Investigations of teriparatide (rPTH) as a potential treatment for critical defects have demonstrated the predicted anabolic effects on bone formation, and significant non-anabolic effects on healing via undefined mechanisms. Specifically, studies in murine models of structural allograft healing demonstrated that rPTH treatment increased angiogenesis (vessels <30μm), and decreased arteriogenesis (>30 μm) and mast cell numbers, which lead to decreased fibrosis and accelerated healing. To better understand these non-anabolic effects, we interrogated osteogenesis, vasculogenesis and mast cell accumulation in mice randomized to placebo (saline), rPTH (20µg/kg/2days), or the mast cell inhibitor sodium cromolyn (SC) (24µg/kg/2days), via longitudinal micro-CT and multiphoton laser scanning microscopy (MPLSM), in a critical calvaria defect model...
May 30, 2017: Journal of Bone and Mineral Research: the Official Journal of the American Society for Bone and Mineral Research
https://www.readbyqxmd.com/read/28556893/a-component-by-component-characterisation-of-high-risk-atherosclerotic-plaques-by-multiphoton-microscopic-imaging
#17
M Jain, B Wu, D Pisapia, S Salvatore, S Mukherjee, N Narula
AIMS: Atherosclerotic plaques vulnerable to rupture are almost always inflamed, and carry a large lipid core covered by a thin fibrous cap. The other components may include neovascularisation, intraplaque haemorrhage and spotty calcification. In contrast, stable plaques are characterised by a predominance of smooth muscle cells and collagen, and lipid core is usually deep seated or absent. This study is a proof of principle experiment to evaluate the feasibility of multiphoton microscopy (MPM) to identify aforementioned plaque components...
May 30, 2017: Journal of Microscopy
https://www.readbyqxmd.com/read/28542327/efficient-up-conversion-in-yb-er-nat-xo4-2-thermal-nanoprobes-imaging-of-their-distribution-in-a-perfused-mouse
#18
Carlos Zaldo, María Dolores Serrano, Xiumei Han, Concepción Cascales, Marta Cantero, Lluís Montoliu, Elvira Arza, Valeria R Caiolfa, Moreno Zamai
Yb and Er codoped NaT(XO4)2 (T = Y, La, Gd, Lu and X = Mo, W) disordered oxides show a green (Er3+ related) up-conversion (UC) efficiency comparable to that of Yb:Er:β-NaYF4 compound and unless 3 times larger UC ratiometric thermal sensitivity. The similar UC efficiency of Yb:Er doped NaT(XO4)2 and β-NaYF4 compounds allowed testing equal subcutaneous depths of ex-vivo chicken tissue in both cases. This extraordinary behavior for NaT(XO4)2 oxides with large cutoff phonon energy (ħω≈ 920 cm-1) is ascribed to 4F9/2 electron population recycling to higher energy 4G11/2 level by a phonon assisted transition...
2017: PloS One
https://www.readbyqxmd.com/read/28536468/il-27r-signaling-controls-myeloid-cells-accumulation-and-antigen-presentation-in-atherosclerosis
#19
Iuliia O Peshkova, Aliia R Fatkhullina, Zbigniew Mikulski, Klaus Ley, Ekaterina K Koltsova
Myeloid cells, key players in atherosclerosis, take up and present antigens, leading to systemic and local T cell activation. The recruitment and activation of immune cells to the aorta in atherosclerosis is regulated by adhesion molecules, chemokines and cytokines. IL-27R is an immunoregulatory signaling nod in autoimmune and infectious pathologies. IL-27R was shown to suppress T cells activation in atherosclerosis, however it's possible role in myeloid cell accumulation and activation is not understood. Here we demonstrate that Apoe (-/-) Il27ra (-/-) mice fed with "Western Diet" for 7 or 18 weeks developed significantly more atherosclerosis compared to Apoe (-/-) Il27ra (+/-) controls...
May 23, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28529998/complement-c5a-receptor-is-the-key-initiator-of-neutrophil-adhesion-igniting-immune-complex-induced-arthritis
#20
Yoshishige Miyabe, Chie Miyabe, Thomas T Murooka, Edward Y Kim, Gail A Newton, Nancy D Kim, Bodduluri Haribabu, Francis W Luscinskas, Thorsten R Mempel, Andrew D Luster
The deposition of immune complexes (IC) in tissues induces a "type III hypersensitivity" that results in tissue damage and underlies the pathogenesis of many autoimmune diseases. The neutrophil is the first immune cell recruited into sites of IC deposition and plays a critical role in shaping the overall tissue response. However, the mechanism by which IC initiate and propagate neutrophil infiltration into tissue is not known. Here, using intravital multiphoton joint imaging of IC-induced arthritis in live mice, we found that the complement C5a receptor (C5aR) was the key initiator of neutrophil adhesion on joint endothelium...
January 2017: Science Immunology
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