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https://www.readbyqxmd.com/read/29778902/perspectives-on-the-past-present-and-future-of-cancer-nanomedicine
#1
Yu Seok Youn, You Han Bae
The justification of cancer nanomedicine relies on enhanced permeation (EP) and retention (R) effect and the capability of intracellular targeting due primarily to size after internalization (endocytosis) into the individual target cells. The EPR effect implies improved efficacy. Affinity targeting for solid tumors only occur after delivery to individual cells, which help internalization and/or retention. The design principles have been supported by animal results in numerous publications, but hardly translated...
May 17, 2018: Advanced Drug Delivery Reviews
https://www.readbyqxmd.com/read/29777957/dual-ph-reduction-responsive-hybrid-polymeric-micelles-for-targeted-chemo-photothermal-combination-therapy
#2
Linhua Zhang, Yu Qin, Zhiming Zhang, Fan Fan, Chenlu Huang, Li Lu, Hai Wang, Xu Jin, Hanxue Zhao, Deling Kong, Chun Wang, Hongfan Sun, Xigang Leng, Dunwan Zhu
The combination of chemotherapy and photothermal therapy in multifunctional nanovesicles has emerged as a promising strategy to improve cancer therapeutic efficacy. Herein, we designed new pH/reduction dual-responsive and folate decorated polymeric micelles (FA Co-PMs) as theranostic nanocarrier to co-encapsulate doxorubicin (DOX) and indocyanine green (ICG) for targeted NIR imaging and chemo-photothermal combination therapy. The Co-PMs exhibited nano-sized structure (∼100 nm) with good monodispersity, high encapsulation efficiency of both ICG and DOX, triggered DOX release in response to acid pH and reduction environment, and excellent temperature conversion with laser irradiation...
May 16, 2018: Acta Biomaterialia
https://www.readbyqxmd.com/read/29775537/amplification-of-dynamic-nuclear-polarization-at-200-ghz-by-arbitrary-pulse-shaping-of-the-electron-spin-saturation-profile
#3
Ilia Kaminker, Songi Han
Dynamic nuclear polarization (DNP) takes center stage in nuclear magnetic resonance (NMR) as a tool to amplify its signal by orders of magnitude through the transfer of polarization from electron to nuclear spins. In contrast to modern NMR and electron paramagnetic resonance (EPR) that extensively rely on pulses for spin manipulation in the time domain, the current mainstream DNP technology exclusively relies on monochromatic continuous wave (CW) irradiation. This study introduces arbitrary phase shaped pulses that constitute a train of coherent chirp pulses in the time domain at 200 GHz (7 Tesla) to dramatically enhance the saturation bandwidth and DNP performance compared to CW DNP, yielding up to 500-fold in NMR signal enhancements...
May 18, 2018: Journal of Physical Chemistry Letters
https://www.readbyqxmd.com/read/29775071/strategy-for-overcoming-full-reversibility-of-intermolecular-radical-addition-to-aldehydes-tandem-c-h-and-c-o-bonds-cleaving-cyclization-of-phenoxymethyl-arenes-with-carbonyls-to-benzofurans
#4
Hong-Xing Zheng, Xiang-Huan Shan, Jian-Ping Qu, Yan-Biao Kang
An intermolecular addition of carbon radicals enabled by a cascade radical coupling strategy is developed. It includes an intermolecular alkyl radical addition to a carbonyl group followed by an intramolecular alkoxy radical addition to haloarenes and produces substituted benzofurans in high yields. The radical nature of this reaction is explored by radical trapping experiments and EPR analysis. The mechanism is investigated by KIE experiments and control experiments. This method could provide rapid and practical access to the key intermediate of TAM-16, a safe and potent antibacterial agent for treating tuberculosis, and, therefore, is of great importance for organic synthesis and the pharmaceutical industry...
May 18, 2018: Organic Letters
https://www.readbyqxmd.com/read/29775060/distinct-populations-in-spin-label-epr-spectra-from-nitroxides
#5
Derek Marsh
It is not possible to reproduce simulations of nitroxide spin-label EPR spectra published in J. Phys. Chem. 88, 3454-3465 (1984), when using the motional model and parameters given in that paper. Instead of the apparent two-component line shapes claimed, the spectra resemble single-component powder patterns expected from axially anisotropic, partial motional-averaging (a situation familiar for chain-labelled lipids in nonaligned fluid membranes). This is because: (i) the nitroxide z-axis is inclined at a fixed angle to the principal diffusion axis, and (ii) motion perpendicular to the principal diffusion axis is so slow as to approximate a powder distribution...
May 18, 2018: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/29774906/reactivity-of-a-dearomatised-pincer-co-ii-br-complex-with-pnc-nhc-donors-alkylation-and-si-h-bond-activation-via-metal-ligand-cooperation
#6
Thomas Simler, Sylvie Choua, Andreas A Danopoulos, Pierre Braunstein
The double aminolysis reaction of [Co{N(SiMe3)2}2] by the salt 1-(6-((dicyclohexylphosphaneyl)methyl)pyridin-2-yl)-3-(2,6-diisopropylphenyl)-1H-imidazol-3-ium bromide, which contains one phosphane, one pyridine and one imidazolium groups, of formula [o-Cy2PCH2(C5H3N)(o-C3H3N2DiPP)]Br and abbreviated as (CyPNpyrCim)Br, was previously shown to afford the Co(ii) complex [Co(CyP*NaCNHC)Br] (1) containing a dearomatised picolyl moiety in the tridentate, anionic donor ligand CyP*NaCNHC (Na = anionic amido, P* = vinylic P donor)...
May 18, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/29774064/tumour-homing-chimeric-polypeptide-conjugated-polypyrrole-nanoparticles-for-imaging-guided-synergistic-photothermal-and-chemical-therapy-of-cancer
#7
Mengmeng Sun, Jianwen Guo, Hanjun Hao, Tong Tong, Kun Wang, Weiping Gao
Near-infrared (NIR)-absorbing conjugated polymer nanoparticles are interesting for imaging-guided combination therapy, especially for synergistic photothermal therapy and chemotherapy; however, most of them target tumours passively through the enhanced permeability and retention (EPR) effect, leading to low utilization efficiency. To address this problem, we report an active tumour-targeting strategy of tumour-homing chimeric polypeptide-conjugated NIR-absorbing conjugated-polymer nanoparticles as a new class of drug nanocarriers for imaging-guided combination therapy of cancer...
2018: Theranostics
https://www.readbyqxmd.com/read/29771534/nitroxyl-modified-tobacco-mosaic-virus-as-a-metal-free-high-relaxivity-mri-and-epr-active-superoxide-sensor
#8
Madushani Dharmarwardana, Andre F Martins, Zhuo Chen, Philip Palacios, Chance M Nowak, Raymond P Welch, Shaobo Li, Michael Andrew Luzuriaga, Leonidas Bleris, Brad S Pierce, A Dean Sherry, Jeremiah J Gassensmith
Superoxide overproduction is known to occur in multiple disease states requiring critical care yet non-invasive detection of superoxide in deep tissue remains a challenge. Herein, we report a metal-free magnetic resonance imaging (MRI) and electron paramagnetic resonance (EPR) active contrast agent prepared by "click conjugating" paramagnetic organic radical contrast agents (ORCAs) to the surface of tobacco mosaic virus (TMV). While ORCAs are known to be reduced in vivo to an MRI/EPR silent state, their oxidation is facilitated specifically by reactive oxygen species-in particular superoxide-and are largely unaffected by peroxides and molecular oxygen...
May 17, 2018: Molecular Pharmaceutics
https://www.readbyqxmd.com/read/29771008/dianionic-titanyl-and-vanadyl-cation-2-m-iv-o-pc-4-2-phthalocyanine-salts-containing-pc-4-macrocycles
#9
Dmitri V Konarev, Alexey V Kuzmin, Salavat S Khasanov, Alexey L Litvinov, Akihiro Otsuka, Hideki Yamochi, Hiroshi Kitagawa, Rimma N Lyubovskaya
In this study, the titanyl and vanadyl phthalocyanine (Pc) salts (Bu4 N+ )2 [MIV O(Pc4- )]2- (M=Ti, V) and (Bu3 MeP+ )2 [MIV O(Pc4- )]2- (M=Ti, V) with [MIV O(Pc4- )]2- dianions were synthesized and characterized. Reduction of MIV O(Pc2- ) carried out with an excess of sodium fluorenone ketyl in the presence of Bu4 N+ or Bu3 MeP+ is exclusive to the phthalocyanine centers, forming Pc4- species. During reduction, the metal +4 charge did not change, implying that Pc is an non-innocent ligand. The Pc negative charge increase caused the C-N(pyr) bonds to elongate and the C-N(imine) bonds to alternate, thus increasing the distortion of Pc...
May 17, 2018: Chemistry, An Asian Journal
https://www.readbyqxmd.com/read/29770935/insight-into-elemental-mercury-hg-0-removal-from-flue-gas-using-uv-h-2-o-2-advanced-oxidation-processes
#10
Changsong Zhou, Zijian Song, Hongmin Yang, Hao Wu, Ben Wang, Jie Yu, Lushi Sun
Elemental mercury (Hg0 ) emitted from coal-fired power plants and municipal solid waste (MSW) incinerators has caused great harm to the environment and human beings. The strong oxidized • OH radicals produced by UV/H2 O2 advanced oxidation processes were studied to investigate the performance of Hg0 removal from simulated flue gases. The results showed that when H2 O2 concentration was 1.0 mol/L and the solution pH value was 4.1, the UV/H2 O2 system had the highest Hg0 removal efficiency. The optimal reaction temperature was approximately 50 °C and Hg0 removal was inhibited when the temperature was higher or lower...
May 16, 2018: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/29768805/an-isomorphously-substituted-fe-bea-zeolite-with-high-fe-content-facile-synthesis-and-characterization
#11
Yusuke Naraki, Ko Ariga, Hideyuki Oka, Hirokazu Kurashige, Tsuneji Sano
An isomorphously substituted Al-free Fe-BEA zeolite with extremely high Fe content (~7 wt.%) was synthesized by a facile and industrially friendly method using an excess amount of NaOH. The obtained Fe-BEA zeolite was highly crystalline and showed a well-facetted bipyramidal morphology, similarly to beta zeolites synthesized in a fluoride medium. The chemical states of Fe in the above zeolite were investigated by diffuse reflectance ultraviolet-visible (UV-Vis) absorption spectroscopy, electron paramagnetic resonance (EPR) spectroscopy, and X-ray absorption fine structure (XAFS) spectroscopy...
January 1, 2018: Journal of Nanoscience and Nanotechnology
https://www.readbyqxmd.com/read/29766795/carboxymethyl-hexanoyl-chitosan-nanodroplets-for-ultrasonic-imaging-and-drug-delivery-to-tumor
#12
Yu Jinsui, Situ Bing, Luo Muhua, Li Yue, Liao Jianyi, Du Meng, Cai Kuan, Yang Chaopin, Zhang Hui, Chen Zhiyi
INTRODUCTION: Although a great many strategies have been proposed for tumor-targeted chemotherapy, current delivery methods of anticancer drugs present limited success with inevitable systemic toxicity. The aim of this study was to develop a new kind of theranostic carrier for targeted tumor therapy. METHODS: Prior to prepare CHC-PFP-DOX, carboxymethyl-hexanoyl chitosan (CHC) was synthesized by acylation of carboxymethyl chitosan. To develop CHC-PFP, perfluoropentane (PFP), an ultrasound gas precursor, were simultaneously encapsulated into the hydrophobic inner cores of pre-formulated CHC micelle in aqueous phase via using the oil in water (O/W) emulsion method...
May 15, 2018: Current Pharmaceutical Design
https://www.readbyqxmd.com/read/29766577/mechanism-of-the-dehydrogenative-phenothiazination-of-phenols
#13
Monalisa Goswami, Alexander Konkel, Maryam Rahimi, Marie-Laure Louillat-Habermeyer, Harald Kelm, Rongwei Jin, Bas de Bruin, Frederic William Patureau
The straightforward capture of oxidized phenothiazines with phenols under aerobic conditions represents a unique case of cross-dehydrogenative C-N bond forming reaction in terms of operational simplicity. The mechanism of this cross dehydrogenative N-arylation of phenothiazines with phenols has been an object of debate, particularly regarding the order in which the substrates are oxidized, and their potentially radical or cationic nature. Understanding the selective reactivity of phenols for oxidized phenothiazines is one of the key objectives of this study...
May 16, 2018: Chemistry: a European Journal
https://www.readbyqxmd.com/read/29766365/iron-overload-prevents-oxidative-damage-to-rat-brain-after-chlorpromazine-administration
#14
Natacha E Piloni, Andres A Caro, Susana Puntarulo
The hypothesis tested is that Fe administration leads to a response in rat brain modulating the effects of later oxidative challenges such as chlorpromazine (CPZ) administration. Either a single dose (acute Fe overload) or 6 doses every second day (sub-chronic Fe overload) of 500 or 50 mg Fe-dextran/kg, respectively, were injected intraperitoneally (ip) to rats. A single dose of 10 mg CPZ/kg was injected ip 8 h after Fe treatment. DNA integrity was evaluated by quantitative PCR, lipid radical (LR· ) generation rate by electron paramagnetic resonance (EPR), and catalase (CAT) activity by UV spectrophotometry in isolated brains...
May 15, 2018: Biometals: An International Journal on the Role of Metal Ions in Biology, Biochemistry, and Medicine
https://www.readbyqxmd.com/read/29766156/copper-catalyzed-selective-radical-radical-cross-coupling-for-c-s-bond-formation-an-access-to-%C3%AE-alkylthionitriles
#15
Caihong Zheng, Fangling Lu, Hanwei Lu, Jie Xin, Yi Deng, Dali Yang, Shengchun Wang, Zhiliang Huang, Meng Gao, Aiwen Lei
A new protocol for C-S bond formation was developed by selective cross-coupling between a thiyl radical and an isobutyronitrile radical. Using this strategy, a series of valuable α-alkylthionitrile derivatives were synthesized from basic starting materials. Preliminary mechanistic investigation was performed by EPR and XAFS, revealing that the transient thiyl radical could be stabilized by a copper catalyst to a persistent one. Therefore, on the basis of the persistent radical effect, selective radical-radical cross-coupling between the thiyl radical and the isobutyronitrile radical was achieved successfully in this work...
May 16, 2018: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/29765372/is-iqg-607-a-potential-metallodrug-or-metallopro-drug-with-a-defined-molecular-target-in-mycobacterium-tuberculosis
#16
REVIEW
Bruno L Abbadi, Valnês da Silva Rodrigues-Junior, Adilio da Silva Dadda, Kenia Pissinate, Anne D Villela, Maria M Campos, Luiz G de França Lopes, Cristiano V Bizarro, Pablo Machado, Eduardo H S Sousa, Luiz A Basso
The emergence of strains of Mycobacterium tuberculosis resistant to isoniazid (INH) has underscored the need for the development of new anti-tuberculosis agents. INH is activated by the mycobacterial katG -encoded catalase-peroxidase, forming an acylpyridine fragment that is covalently attached to the C4 of NADH. This isonicotinyl-NAD adduct inhibits the activity of 2- trans -enoyl-ACP(CoA) reductase (InhA), which plays a role in mycolic acid biosynthesis. A metal-based INH analog, Na3 [FeII (CN)5 (INH)]·4H2 O, IQG-607, was designed to have an electronic redistribution on INH moiety that would lead to an intramolecular electron transfer to bypass KatG activation...
2018: Frontiers in Microbiology
https://www.readbyqxmd.com/read/29763519/generation-and-characterization-of-the-first-persistent-platinum-i-centered-radical
#17
Yosi Kratish, Arseni Kostenko, Alexander Kaushansky, Boris Tumanskii, Dmitry Bravo-Zhivotovskii, Yitzhak Apeloig
The first persistent platinum(I) centered radical was generated by homolytic cleavage of a Pt-HgSiR3 bond of a mercury substituted platinum(II) complex. The Pt(I) radical is characterized by EPR spectroscopy, chemical trapping experiments and density functional theory (DFT) calculations.
May 15, 2018: Angewandte Chemie
https://www.readbyqxmd.com/read/29761596/the-electronic-pharmaceutical-record-a-new-method-for-medication-reconciliation
#18
Camille Jurado, Violaine Calmels, Emilie Lobinet, Elodie Divol, Hélène Hanaire, David Metsu, Brigitte Sallerin
RATIONALE, AIM, AND OBJECTIVE: There are several ways to establish an accurate medication list in the hospital admission medication reconciliation (MedRec). The challenge for MedRec lies in the availability, reliability, and completeness of the data used. In France, the Electronic Pharmaceutical Record (ePR) was developed to register each medication taken by ambulatory patients, primarily to make dispensation in community pharmacies safe. We evaluated the suitability of this tool in the MedRec when patients were admitted to the hospital...
May 15, 2018: Journal of Evaluation in Clinical Practice
https://www.readbyqxmd.com/read/29758428/threats-to-coastal-communities-of-mahanadi-delta-due-to-imminent-consequences-of-erosion-present-and-near-future
#19
Anirban Mukhopadhyay, Pramit Ghosh, Abhra Chanda, Amit Ghosh, Subhajit Ghosh, Shouvik Das, Tuhin Ghosh, Sugata Hazra
Coastal erosion is a natural hazard which causes significant loss to properties as well as coastal habitats. Coastal districts of Mahanadi delta, one of the most populated deltas of the Indian subcontinent, are suffering from the ill effects of coastal erosion. An important amount of assets is being lost every year along with forced migration of huge portions of coastal communities due to erosion. An attempt has been made in this study to predict the future coastline of the Mahanadi Delta based on historical trends...
May 11, 2018: Science of the Total Environment
https://www.readbyqxmd.com/read/29756781/frequency-swept-integrated-and-stretched-solid-effect-dnp
#20
Thach Van Can, Johannes E McKay, Ralph T Weber, Chen Yang, Thierry Dubroca, Johan Van Tol, Stephen Hill, Robert G Griffin
We investigate a new time domain approach to dynamic nuclear polarization (DNP), the frequency-swept integrated solid effect (FS-ISE), utilizing a high power, broadband 94 GHz (3.35 T) pulse EPR spectrometer. The bandwidth of the spectrometer enabled measurement of the DNP Zeeman frequency/field profile that revealed two dominant polarization mechanisms, the expected ISE, and a new mechanism the stretched solid effect (S2E). At 94 GHz, despite the limitations in the microwave chirp pulse length (10 μs) and the repetition rate (2 kHz), we obtained signal enhancements up ~70 for the S2E and ~50 for the ISE...
May 14, 2018: Journal of Physical Chemistry Letters
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