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https://www.readbyqxmd.com/read/28918081/developmental-alcohol-exposure-impairs-synaptic-plasticity-without-overtly-altering-microglial-function-in-mouse-visual-cortex
#1
Elissa L Wong, Nina M Lutz, Victoria A Hogan, Cassandra E Lamantia, Helene R McMurray, Jason R Myers, John M Ashton, Ania K Majewska
Fetal alcohol spectrum disorder (FASD), caused by gestational ethanol (EtOH) exposure, is one of the most common causes of non-heritable and life-long mental disability worldwide, with no standard treatment or therapy available. While EtOH exposure can alter the function of both neurons and glia, it is still unclear how EtOH influences brain development to cause deficits in sensory and cognitive processing later in life. Microglia play an important role in shaping synaptic function and plasticity during neural circuit development and have been shown to mount an acute immunological response to EtOH exposure in certain brain regions...
September 13, 2017: Brain, Behavior, and Immunity
https://www.readbyqxmd.com/read/28916873/effects-of-methotrexate-on-the-quality-of-oocyte-maturation-in-vitro
#2
N Tian, J Yu, Sh Zhang, W Y Ma, T Wang, Y M Wang
Methotrexate (MTX), an antifolate drug, is widely used for clinical treatment of malignancies and ectopic pregnancy. Many studies have documented that MTX has strong side-effects on rapidly dividing somatic cells. However, its side-effects on female reproductive cells have not been widely reported. Combined with in vitro culture, two-photon fluorescence imaging and three-dimensional reconstruction, this study analyzed the effects of MTX on oocyte maturation time, chromosome arrangement, karyotype, spindle morphology, and the localization of microtubule organizing centers (MTOCs)...
September 15, 2017: European Biophysics Journal: EBJ
https://www.readbyqxmd.com/read/28916622/quantification-and-determination-of-normal-123-i-meta-iodobenzylguanidine-heart-to-mediastinum-ratio-hmr-from-cardiac-spect-ct-and-correlation-with-planar-hmr
#3
Raza Alvi, Edward J Miller, Taraneh Hashemi Zonouz, Veronica Sandoval, Noor Tariq, Rachel Lampert, Albert J Sinusas, Yi-Hwa Liu
Assessment of cardiac (123)I-mIBG uptake relies on the heart-to-mediastinal ratio (HMR) derived from planar images. We have developed novel semi-automated quantitative methodologies for assessing HMR from single photon emission computed tomography (SPECT) images using a dedicated cardiac multi-pinhole SPECT/computerized tomography (CT) system and determined the lower limit of normal (LLN) SPECT-derived HMR and the correlation to planar-derived HMR. Methods: Twenty-one healthy volunteers were injected with (123)I-meta Iodobenzylguanidine ((123)I-mIBG) and imaged using two different cameras...
September 15, 2017: Journal of Nuclear Medicine: Official Publication, Society of Nuclear Medicine
https://www.readbyqxmd.com/read/28915944/a-novel-substrate-inspired-fluorescent-probe-to-monitor-native-albumin-in-human-plasma-and-living-cells
#4
Guang-Bo Ge, Lei Feng, Qiang Jin, Yi-Ru Wang, Zhao-Ming Liu, Xin-Yue Zhu, Ping Wang, Jie Hou, Jing-Nan Cui, Ling Yang
Human albumin (HA) displays crucial roles in maintaining health and fighting diseases. Accurate determination of native HA in plasma or non-plasma samples are of immense significance in both basic research and clinical practice. Herein, a novel ratiometric two-photon fluorescent probe (N-butyl-4-(4-phenyl-benzoyloxy) 1,8-naphthalimide, BPBN) has been designed and developed for highly selective and sensitive sensing the enzymatic activities of HA, on the basis of its unique pseudo-esterase feature. BPBN exhibits excellent selectivity, high sensitivity and good reactivity under physiological conditions...
October 9, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28915047/two-photon-absorption-in-pentacene-dimers-the-importance-of-the-tether-using-upconversion-as-an-indirect-route-to-singlet-fission
#5
Eleonora Garoni, Johannes Zirzlmeier, Bettina S Basel, Constantin Hetzer, Kenji Kamada, Dirk M Guldi, Rik R Tykwinski
In this proof of concept study, we show that intramolecular singlet fission (iSF) can be initiated from a singlet excited state accessed by two-photon absorption, rather than through a tradition route of direct one-photon excitation (OPE). Thus, iSF in pentacene dimers 2 and 3 is enabled through NIR irradiation at 775 nm, a wavelength where neither dimer exhibits linear absorption of light. The meta-phenylene and adamantyl tethers 2 and 3, respectively, are designed to feature superimposable geometry, which establishes that the electronic coupling between the two pentacenes is the significant structural feature that dictates iSF efficiency...
September 15, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28914912/quasiperiodic-one-dimensional-photonic-crystals-with-adjustable-multiple-photonic-bandgaps
#6
Andrey M Vyunishev, Pavel S Pankin, Sergey E Svyakhovskiy, Ivan V Timofeev, Stepan Ya Vetrov
We propose an elegant approach to produce photonic bandgap (PBG) structures with multiple photonic bandgaps by constructing quasiperiodic photonic crystals (QPPCs) composed of a superposition of photonic lattices with different periods. Generally, QPPC structures exhibit both aperiodicity and multiple PBGs due to their long-range order. They are described by a simple analytical expression, instead of quasiperiodic tiling approaches based on substitution rules. Here we describe the optical properties of QPPCs exhibiting two PBGs that can be tuned independently...
September 15, 2017: Optics Letters
https://www.readbyqxmd.com/read/28914908/phase-matched-nonlinear-optics-via-patterning-layered-materials
#7
Taylor K Fryett, Alan Zhan, Arka Majumdar
The ease of integration and a large second-order nonlinear coefficient of atomically thin layered two-dimensional (2D) materials presents a unique opportunity to realize second-order nonlinearity in a silicon compatible integrated photonic system. However, the phase-matching requirement for second-order nonlinear optical processes makes the nanophotonic design difficult. We show that by nano-patterning the 2D material, quasi-phase-matching can be achieved. Such patterning-based quasi-phase-matching could potentially compensate for inevitable fabrication errors and significantly simplify the design process of the nonlinear nanophotonic devices...
September 15, 2017: Optics Letters
https://www.readbyqxmd.com/read/28914897/dual-frequency-doppler-lidar-for-wind-detection-with-a-superconducting-nanowire-single-photon-detector
#8
Mingjia Shangguan, Haiyun Xia, Chong Wang, Jiawei Qiu, Shengfu Lin, Xiankang Dou, Qiang Zhang, Jian-Wei Pan
A dual-frequency direct detection Doppler lidar is demonstrated using a superconducting nanowire single-photon detector (SNSPD) at 1.5 μm. The so-called double-edge technique is implemented by using a dual-frequency laser pulse, rather than using a double-channel Fabry-Perot interferometer. Such a modification to the reported lidars enhances the frequency stability in the system level. Using the time-division multiplexing method, only one piece of SNSPD is used in the optical receiver, making the system simplified and robust...
September 15, 2017: Optics Letters
https://www.readbyqxmd.com/read/28914613/a-novel-system-for-commissioning-brachytherapy-applicators-example-of-a-ring-applicator
#9
Gabriel Paiva Fonseca, Michiel R van den Bosch, Robert Voncken, Mark Podesta, Frank Verhaegen
A novel system was developed to improve commissioning and quality assurance of brachytherapy applicators used in High Dose Rate (HDR). It employs an imaging panel to create reference images and to measure dwell times and dwell positions. As an example: two ring applicators of the same model were evaluated. An applicator was placed on the surface of an imaging panel and a HDR 192Ir source was positioned in an imaging channel above the panel to generate an image of the applicator, using the gamma photons of the brachytherapy source...
September 15, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28911321/q-a-the-brain-under-a-mesoscope-the-forest-and-the-trees
#10
Nicholas James Sofroniew
Neurons relevant to a particular behavior are often widely dispersed across the brain. To record activity in groups of individual neurons that might be distributed across large distances, neuroscientists and optical engineers have been developing a new type of microscope called a mesoscope. Mesoscopes have high spatial resolution and a large field of view. This Q&A will discuss this exciting new technology, highlighting a particular instrument, the two-photon random access mesoscope (2pRAM).
September 14, 2017: BMC Biology
https://www.readbyqxmd.com/read/28910617/whole-cell-recording-of-neuronal-membrane-potential-during-behavior
#11
REVIEW
Carl C H Petersen
Neuronal membrane potential is of fundamental importance for the mechanistic understanding of brain function. This review discusses progress in whole-cell patch-clamp recordings for low-noise measurement of neuronal membrane potential in awake behaving animals. Whole-cell recordings can be combined with two-photon microscopy to target fluorescently labeled neurons, revealing cell-type-specific membrane potential dynamics of retrogradely or genetically labeled neurons. Dual whole-cell recordings reveal behavioral modulation of membrane potential synchrony and properties of synaptic transmission in vivo...
September 13, 2017: Neuron
https://www.readbyqxmd.com/read/28910360/transgelin-2-is-upregulated-on-activated-b-cells-and-expressed-in-hyperplastic-follicles-in-lupus-erythematosus-patients
#12
Kaori Kiso, Hajime Yoshifuji, Takuma Oku, Masaki Hikida, Koji Kitagori, Yoshitaka Hirayama, Toshiki Nakajima, Hironori Haga, Tatsuaki Tsuruyama, Aya Miyagawa-Hayashino
Transgelin-2 (TAGLN2) is an actin-binding protein that controls actin stability and promotes T cell activation. TAGLN2 is also expressed on B-cells but its function in B-cells is unknown. We found that TAGLN2-expressing B-cells were localized in the germinal center (GC) of secondary lymphoid tissues and TAGLN2 mRNA was significantly upregulated after IgM+IgG stimulation in primary human B-cells, suggesting that TAGLN2 was upregulated upon B-cell activation. In support of this, lymph nodes (LNs) from patients with systemic lupus erythematosus (SLE), in which the intense GC activity have been recognized, showed increased TAGLN2 expression in B-cells compared to control LNs...
2017: PloS One
https://www.readbyqxmd.com/read/28910077/and-there-was-light-prospects-for-the-creation-of-micro-and-nanostructures-through-maskless-photolithography
#13
J Rühe
In photolithographic processes, the light inducing the photochemical reactions is confined to a small volume, which enables direct writing of micro- and nanoscale features onto solid surfaces without the need of a predefined photomask. The direct writing process can be used to generate topographic patterns through photopolymerization or photo-cross-linking or can be employed to use light to generate chemical patterns on the surface with high spatial control, which would make such processes attractive for bioapplications...
September 14, 2017: ACS Nano
https://www.readbyqxmd.com/read/28906462/time-resolved-diffuse-optical-spectroscopy-and-imaging-using-solid-state-detectors-characteristics-present-status-and-research-challenges
#14
REVIEW
Mrwan Alayed, M Jamal Deen
Diffuse optical spectroscopy (DOS) and diffuse optical imaging (DOI) are emerging non-invasive imaging modalities that have wide spread potential applications in many fields, particularly for structural and functional imaging in medicine. In this article, we review time-resolved diffuse optical imaging (TR-DOI) systems using solid-state detectors with a special focus on Single-Photon Avalanche Diodes (SPADs) and Silicon Photomultipliers (SiPMs). These TR-DOI systems can be categorized into two types based on the operation mode of the detector (free-running or time-gated)...
September 14, 2017: Sensors
https://www.readbyqxmd.com/read/28904390/quantum-interference-in-the-presence-of-a-resonant-medium
#15
Dmitry A Kalashnikov, Elizaveta V Melik-Gaykazyan, Alexey A Kalachev, Ye Feng Yu, Arseniy I Kuznetsov, Leonid A Krivitsky
Interaction of light with media often occurs with a femtosecond response time. Its measurement by conventional techniques requires the use of femtosecond lasers and sophisticated time-gated optical detection. Here we demonstrate that by exploiting quantum interference of entangled photons it is possible to measure the dephasing time of a resonant media on the femtosecond time scale (down to 100 fs) using accessible continuous wave laser and single-photon counting. We insert a sample in the Hong-Ou-Mandel interferometer and observe the modification of the two-photon interference pattern, which is driven by the coherent response of the medium, determined by the dephasing time...
September 13, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28902766/future-cardiac-events-in-patients-with-ischemic-ecg-changes-during-adenosine-infusion-as-a-myocardial-stress-agent-and-normal-cardiac-scan
#16
Hamid Amer, Khalid Niaz, Jun Hatazawa, Ahmed Gasmelseed, Hussain Al Samiri, Maram Al Othman, Mai Al Hammad
BACKGROUND: We sought to determine the prognostic importance of adenosine-induced ischemic ECG changes in patients with normal single-photon emission computed tomography myocardial perfusion images (MPI). PATIENTS AND METHODS: We carried out a retrospective analysis of 765 patients undergoing adenosine MPI between January 2013 and January 2015. Patients with baseline ECG abnormalities and/or abnormal scan were excluded. RESULTS: Overall, 67 (8...
September 11, 2017: Nuclear Medicine Communications
https://www.readbyqxmd.com/read/28902254/condylectomy-and-surgery-first-approach-an-expedited-treatment-for-condylar-hyperplasia-in-a-patient-with-facial-asymmetry
#17
Diego Fernando López, Juan Fernando Aristizábal, Rosana Martínez-Smit
Condylar Hyperplasia (CH) is a self-limiting pathology condition that produces severe facial deformity at the expense of mandibular asymmetry. In this case report a 15-year-old female patient was diagnosed with Unilateral Condylar Hiperplasia (UCH) by mean of single-photon emission computed tomography (SPECT) and histological study. A high condylectomy in the right condyle was performed to stop the active status of the hyperplasia. A month after condylectomy, orthognathic jaw impaction and asymmetric mandibular setback surgery was performed with the Surgery First Approach (SFA)...
July 2017: Dental Press Journal of Orthodontics
https://www.readbyqxmd.com/read/28901619/nonuniqueness-in-dual-energy-ct
#18
Zachary H Levine
PURPOSE: The goal is to determine whether dual-energy computed tomography (CT) leads to a unique reconstruction using two basis materials. METHODS: The beam-hardening equation is simplified to the single-voxel case. The simplified equation is rewritten to show that the solution can be considered to be linear operations in a vector space followed by a measurement model which is the sum of the exponential of the coordinates. The case of finding the concentrations of two materials from measurements of two spectra with three photon energies is the simplest non-trivial case and is considered in detail...
September 2017: Medical Physics
https://www.readbyqxmd.com/read/28901616/regularization-of-nonlinear-decomposition-of-spectral-x-ray-projection-images
#19
Nicolas Ducros, Juan Felipe Perez-Juste Abascal, Bruno Sixou, Simon Rit, Françoise Peyrin
PURPOSE: Exploiting the x-ray measurements obtained in different energy bins, spectral computed tomography (CT) has the ability to recover the 3-D description of a patient in a material basis. This may be achieved solving two subproblems, namely the material decomposition and the tomographic reconstruction problems. In this work, we address the material decomposition of spectral x-ray projection images, which is a nonlinear ill-posed problem. METHODS: Our main contribution is to introduce a material-dependent spatial regularization in the projection domain...
September 2017: Medical Physics
https://www.readbyqxmd.com/read/28901579/formation-and-photodynamic-behavior-of-transition-metal-dichalcogenide-nanosheet-fullerene-inorganic-organic-nanohybrids-on-semiconducting-electrodes
#20
Jinseok Baek, Tomokazu Umeyama, Wookjin Choi, Yusuke Tsutsui, Hiroki Yamada, Shu Seki, Hiroshi Imahori
Composite films consisting of C60 and well-exfoliated nanosheets of transition metal dichalcogenides (TMDs), i.e., MoS2 or WS2, with a bulk heterojunction structure were facilely fabricated onto a semiconducting SnO2 electrode via a two-step methodology; self-assembly into their composite aggregates by injecting poor solvent into good solvent with the dispersion and subsequent electrophoretic deposition. Photoexcitation of the composites on SnO2 exhibited enhanced transient conductivities in comparison with single components of TMDs or C60, demonstrating that the bulk heterojunction nanostructure of TMD and C60 promoted the charge separation (CS)...
September 13, 2017: Chemistry: a European Journal
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