Discovery and Insight into One-photon and Two-photon Excited ACQ-to-AIE Conversion via Positional Isomerization

A presence of bulky 2,6-di-iso-propylphenoxy groups in bis-tert-butylisocyano adduct of 2(3),9(10),16(17),23(24)-tetrachloro-3(2),10(9),17(16),24(23)-tetra(2,6-di-iso-propylphenoxy)-phthalocyaninato iron(II) complex allows separation of two individual positional isomers and a mixture of the remaining two isomers using conventional chromatography. X-ray structures of “[Formula: see text]” and “[Formula: see text]” isomers were confimed by X-ray crystallography. Density functional theory (DFT) and time-dependent DFT (TDDFT) calculations of each individual positional isomer allowed insight into their electronic structures and vertical excitation energies, which were correlated with the experimental UV-vis and MCD spectra.

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Spontaneous activations follow a common developmental course across primary sensory areas in mouse neocortex

Journal of Neurophysiology ◽

10.1152/jn.00172.2016 ◽

2016 ◽

Vol 116 (2) ◽

pp. 431-437 ◽

Cited By ~ 6

Author(s):

Charles G. Frye ◽

Jason N. MacLean

Keyword(s):

Calcium Imaging ◽

Sensory Input ◽

Primary Auditory Cortex ◽

Developmental Trajectory ◽

Two Photon ◽

Developmental Progression ◽

Sensory Modalities ◽

Spatially Distributed ◽

And Function ◽

Insight Into

Spontaneous propagation of spiking within the local neocortical circuits of mature primary sensory areas is highly nonrandom, engaging specific sets of interconnected and functionally related neurons. These spontaneous activations promise insight into neocortical structure and function, but their properties in the first 2 wk of perinatal development are incompletely characterized. Previously, we have found that there is a minimal numerical sample, on the order of 400 cells, necessary to fully capture mature neocortical circuit dynamics. Therefore we maximized our numerical sample by using two-photon calcium imaging to observe spontaneous activity in populations of up to 1,062 neurons spanning multiple columns and layers in 52 acute coronal slices of mouse neocortex at each day from postnatal day (PND) 3 to PND 15. Slices contained either primary auditory cortex (A1) or somatosensory barrel field (S1BF), which allowed us to compare sensory modalities with markedly different developmental timelines. Between PND 3 and PND 8, populations in both areas exhibited activations of anatomically compact subgroups on the order of dozens of cells. Between PND 9 and PND 13, the spatiotemporal structure of the activity diversified to include spatially distributed activations encompassing hundreds of cells. Sparse activations covering the entire field of view dominated in slices taken on or after PND 14. These and other findings demonstrate that the developmental progression of spontaneous activations from active local modules in the first postnatal week to sparse, intermingled groups of neurons at the beginning of the third postnatal week generalizes across primary sensory areas, consistent with an intrinsic developmental trajectory independent of sensory input.

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Saturation of Two-Photon Excitation Provides Insight into the Effects of a Quantum Dot Blinking Suppressant: A Fluorescence Correlation Spectroscopy Study

The Journal of Physical Chemistry C ◽

10.1021/jp709604j ◽

2007 ◽

Vol 111 (51) ◽

pp. 18942-18949 ◽

Cited By ~ 17

Author(s):

Romey F. Heuff ◽

Michele Marrocco ◽

David T. Cramb

Keyword(s):

Quantum Dot ◽

Fluorescence Correlation Spectroscopy ◽

Correlation Spectroscopy ◽

Spectroscopy Study ◽

Fluorescence Correlation ◽

Two Photon ◽

Photon Excitation ◽

Insight Into ◽

Two Photon Excitation

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The spectroscopy of jet-cooled porphyrins: an insight into the vibronic structure of the Q band

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424610002094 ◽

2010 ◽

Vol 14 (04) ◽

pp. 314-323 ◽

Cited By ~ 3

Author(s):

Joseph M. Beames ◽

Timothy D. Vaden ◽

Andrew J. Hudson

Keyword(s):

Laser Desorption ◽

Electronic Transitions ◽

Quantum Mechanical ◽

Supersonic Expansion ◽

Two Photon ◽

Vibrational Levels ◽

Inert Carrier ◽

Mechanical Interpretation ◽

Photon Ionization ◽

Insight Into

We will present resonant two-photon ionization spectra for meso-tetraphenylporphyrin, H 2 TPP , measured under isolated conditions. The polycrystalline compound was vaporized, in vacuo, using both thermal and laser desorption, and seeded into a supersonic expansion of an inert-carrier gas. The molecules remain largely intact in the gaseous phase. However, the two techniques for vaporizing H 2 TPP give different internal temperatures for the isolated substrate, with greater vibrational cooling achieved using laser desorption. A comparison of the peak positions and intensities in the resonant two-photon ionization spectra of thermal- and laser-desorbed molecules provides an insight into the vibrational structure of the Q band. In particular, the greater contribution made by electronic transitions originating from higher vibrational levels in the ground state of H 2 TPP is emphasized. We conclude that vibronic coupling in the ground electronic state plays an important role in a quantum-mechanical interpretation of the Q band.

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Distinct functional classes of excitatory neurons in mouse V1 are differentially modulated by learning and task engagement

10.1101/533463 ◽

2019 ◽

Cited By ~ 3

Author(s):

Joseph B. Wekselblatt ◽

Cristopher M. Niell

Keyword(s):

Temporal Dynamics ◽

Task Engagement ◽

Neural Responses ◽

Two Photon ◽

Neural Representations ◽

Excitatory Neurons ◽

Before And After ◽

Functional Classes ◽

Insight Into ◽

And Task

AbstractLearning can cause significant changes in neural responses to relevant stimuli, in addition to modulation due to task engagement. However, it is not known how different functional types of excitatory neurons contribute to these changes. To address this gap, we performed two-photon calcium imaging of excitatory neurons in layer 2/3 of mouse primary visual cortex before and after learning of a visual discrimination. We found that excitatory neurons show striking diversity in the temporal dynamics of their response to visual stimuli during the behavior, and based on this we classified them into transient, sustained, and suppressed groups. Notably, these functionally defined cell classes exhibit different visual stimulus selectivity and modulation by locomotion, and were differentially affected by training condition. In particular, we observed a decrease in the number of transient neurons responsive during behavior after learning, while both transient and sustained cells showed an increase in modulation due to task engagement after learning. The identification of functional diversity within the excitatory population, with distinct changes during learning and task engagement, provides insight into the cortical pathways that allow context-dependent neural representations.

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A Detailed Microscopic Insight into the Aggregation Behaviors of Doxorubicin Hydrochloride in Different Microheterogeneous Media

Biophysical Journal ◽

10.1016/j.bpj.2018.11.486 ◽

2019 ◽

Vol 116 (3) ◽

pp. 82a

Author(s):

Arghajit Pyne ◽

Sangita Kundu ◽

Pavel Banerjee ◽

Nilmoni Sarkar

Keyword(s):

Doxorubicin Hydrochloride ◽

Aggregation Behaviors ◽

Insight Into ◽

Microheterogeneous Media

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Hexadecenoic Fatty Acid Positional Isomers and De Novo PUFA Synthesis in Colon Cancer Cells

International Journal of Molecular Sciences ◽

10.3390/ijms20040832 ◽

2019 ◽

Vol 20 (4) ◽

pp. 832 ◽

Cited By ~ 10

Author(s):

Roberta Scanferlato ◽

Massimo Bortolotti ◽

Anna Sansone ◽

Chryssostomos Chatgilialoglu ◽

Letizia Polito ◽

...

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Cancer Cells ◽

De Novo ◽

Fluorescent Microscopy ◽

Positional Isomers ◽

Membrane Phospholipids ◽

Two Photon ◽

Palmitic Acids ◽

Delta 6 Desaturase

Palmitic acid metabolism involves delta-9 and delta-6 desaturase enzymes forming palmitoleic acid (9cis-16:1; n-7 series) and sapienic acid (6cis-16:1; n-10 series), respectively. The corresponding biological consequences and lipidomic research on these positional monounsaturated fatty acid (MUFA) isomers are under development. Furthermore, sapienic acid can bring to the de novo synthesis of the n-10 polyunsaturated fatty acid (PUFA) sebaleic acid (5cis,8cis-18:2), but such transformations in cancer cells are not known. The model of Caco-2 cell line was used to monitor sapienic acid supplementation (150 and 300 μM) and provide evidence of the formation of n-10 fatty acids as well as their incorporation at levels of membrane phospholipids and triglycerides. Comparison with palmitoleic and palmitic acids evidenced that lipid remodelling was influenced by the type of fatty acid and positional isomer, with an increase of 8cis-18:1, n-10 PUFA and a decrease of saturated fats in case of sapienic acid. Cholesteryl esters were formed only in cases with sapienic acid. Sapienic acid was the less toxic among the tested fatty acids, showing the highest EC50s and inducing death only in 75% of cells at the highest concentration tested. Two-photon fluorescent microscopy with Laurdan as a fluorescent dye provided information on membrane fluidity, highlighting that sapienic acid increases the distribution of fluid regions, probably connected with the formation of 8cis-18:1 and the n-10 PUFA in cell lipidome. Our results bring evidence for MUFA positional isomers and de novo PUFA synthesis for developing lipidomic analysis and cancer research.

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Theoretical insight into the photophysical properties of long-lifetime Ir(iii) and Rh(iii) complexes for two-photon photodynamic therapy

Physical Chemistry Chemical Physics ◽

10.1039/c9cp00512a ◽

2019 ◽

Vol 21 (16) ◽

pp. 8394-8401 ◽

Cited By ~ 2

Author(s):

Xue Yin ◽

Xiao-Yong Lai ◽

Xin Wang ◽

Ying-Tao Liu

Keyword(s):

Photodynamic Therapy ◽

Photophysical Properties ◽

Deep Penetration ◽

Two Photon ◽

Minimal Damage ◽

Long Lifetime ◽

Theoretical Insight ◽

Insight Into

Two-photon photodynamic therapy (TP-PDT) plays crucial roles in curing tumors because it involves deep penetration of drugs into the tissue and has minimal damage to the surrounding cells.

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A MD Simulation and Analysis for Aggregation Behaviors of Nanoscale Zero-Valent Iron Particles in Water via MS

The Scientific World JOURNAL ◽

10.1155/2014/768780 ◽

2014 ◽

Vol 2014 ◽

pp. 1-13 ◽

Cited By ~ 2

Author(s):

Ying Zhao ◽

Dongmei Liu ◽

Huan Tang ◽

Jing Lu ◽

Fuyi Cui

Keyword(s):

Particle Size ◽

Water Environment ◽

Simulation System ◽

Theoretical Research ◽

Initial Distance ◽

Aggregation Behaviors ◽

Dynamics Simulations ◽

Existing Form ◽

Materials Studio ◽

Insight Into

With the development of nanotechnology, more nanomaterials will enter into water environment system. Studying the existing form of nanomaterials in water environment will help people benefit from the correct use of them and to reduce the harm to human caused by them for some nanomaterials can bring polluting effect. Aggregation is a main behavior for nanoparticle in water environment. NZVI are used widely in many fields resulting in more NZVI in water environment. Molecular dynamics simulations and Materials Studio software are used to investigate the microaggregation behaviors of NZVI particles. Two scenes are involved: (1) particle size of NZVI in each simulation system is the same, but initial distance of two NZVI particles is different; (2) initial distance of two NZVI particles in each simulation system is the same, but particle size of NZVI is different. Atomistic trajectory, NP activity, total energy, and adsorption of H2O are analyzed with MS. The method provides new quantitative insight into the structure, energy, and dynamics of the aggregation behaviors of NZVI particles in water. It is necessary to understand microchange of NPs in water because it can provide theoretical research that is used to reduce polluting effect of NPs on water environment.

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