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https://www.readbyqxmd.com/read/29245122/reduction-of-cancer-cell-viability-by-synergistic-combination-of-photodynamic-treatment-with-the-inhibition-of-the-id-protein-family
#1
Cornelia Roschger, Thomas Verwanger, Barbara Krammer, Chiara Cabrele
The inhibitor of DNA binding and cell differentiation (Id) proteins are dominant negative regulators of the helix-loop-helix transcription factor family and play a key role during development as well as in vascular disorders and cancer. In fact, impairing the Id-protein activity in cancer cells reduces cell growth and even chemoresistance. Recently, we have shown that a synthetic Id-protein ligand (1Y) consisting of a cyclic nonapeptide can reduce the viability of the two breast cancer cell lines MCF-7 and T47D and of the bladder cancer cells T24 to about 50% at concentrations ≥100μM...
December 5, 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/29243919/zinc-ii-metalated-porphyrins-as-photothermogenic-photosensitizers-for-cancer-photodynamic-photothermal-synergistic-therapy
#2
Kaikai Ding, Ye-Wei Zhang, Weili Si, Xiangmin Zhong, Yu Cai, Jianhua Zou, Jinjun Shao, Zhou Yang, Xiaochen Dong
Porphyrin derivatives are the first-generation photosensitizers, and to design a strong NIR-absorbing porphyrin with good water solubility is highly desired for better therapeutic effect to treat tumors. Herein, three new porphyrin derivatives, 5,10,15,20-tetrakis(3,4- dimethoxyphenyl) porphyrin (P1), 5,10,15,20-tetrakis(3,4-dimethoxyphenyl) Zinc porphyrin (ZnP1), and 5,15-bis (3,4-dimethoxyphenyl)-10,20-bis ((4-methoxyphenyl)ethynyl) Zinc porphyrin (ZnP2) have been synthesized. Among them, ZnP2 shows the longest and most intensive Q-bands in the near-infrared (NIR) region, as endows it the strongest light-harvesting capability and deepest tumor tissue penetration...
December 15, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/29243759/an-insight-into-the-photodynamic-approach-versus-copper-formulations-in-the-control-of-pseudomonas-syringae-pv-actinidiae-in-kiwi-plants
#3
Vânia Jesus, Diana Martins, Tatiana Branco, Nádia Valério, Maria G P M S Neves, Maria A F Faustino, Luís Reis, Esther Barreal, Pedro P Gallego, Adelaide Almeida
In the last decade, the worldwide production of kiwi fruit has been highly affected by Pseudomonas syringae pv. actinidiae (Psa), a phytopathogenic bacterium; this has led to severe economic losses that are seriously affecting the kiwi fruit trade. The available treatments for this disease are still scarce, with the most common involving frequently spraying the orchards with copper derivatives, in particular cuprous oxide (Cu2O). However, these copper formulations should be avoided due to their high toxicity; therefore, it is essential to search for new approaches for controlling Psa...
December 15, 2017: Photochemical & Photobiological Sciences
https://www.readbyqxmd.com/read/29243345/deoxythymidine-pterin-fluorescent-adduct-formation-by-a-photosensitized-proccess
#4
Sandra Estébanez, Andrés H Thomas, Carolina Lorente
A new fluorescent compound was isolated from UV-A irradiated aqueous solutions containing pterin (Ptr) and 2´deoxythymidine (dT) in anaerobic conditions. Pterins are widespread in the living systems in small amounts, but they are accumulated in some pathological situations. Under UV-A radiation, pterins are photochemically active, fluorescent and photosensitize the generation of singlet oxygen (1O2(1Δg)). The isolated compound was structurally characterized, by liquid chromatography coupled to tandem mass spectrometry, and its photophysical properties were studied by time correlated single photon counting technique...
December 15, 2017: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
https://www.readbyqxmd.com/read/29242903/interface-bonding-with-corneal-crosslinking-cxl-after-lasik-ex-vivo
#5
Theo G Seiler, Marleen Engler, Eric Beck, Reginald Birngruber, Irene E Kochevar
Purpose: Interface bonding with corneal crosslinking (CXL) after LASIK using two different photosensitizers was studied ex vivo. Methods: A LASIK flap was created in enucleated rabbit eyes using a femtosecond laser. After the dissection, CXL was performed to seal the interface. In one group interface CXL was performed using rose bengal and green light, whereas in a second group riboflavin and UV-A light was used. In both groups irradiance, radiant exposure, dye concentration, and imbibition time was varied...
December 1, 2017: Investigative Ophthalmology & Visual Science
https://www.readbyqxmd.com/read/29242243/an-infrared-dye-conjugated-virus-like-particle-for-the-treatment-of-primary-uveal-melanoma
#6
Rhonda C Kines, Isabella Varsavsky, Sanghamitra Choudhary, Debaditya Bhattacharya, Sean Spring, Roger J McLaughlin, Shin J Kang, Hans E Grossniklaus, Demitrios G Vavvas, Stephen Monks, John R MacDougall, Elisabet de Los Pinos, John T Schiller
The work outlined herein describes AU-011, a novel recombinant papillomavirus-like particle (VLP) drug conjugate and its initial evaluation as a potential treatment for primary uveal melanoma. The VLP is conjugated with a phthalocyanine photosensitizer, IRDye 700DX, that exerts its cytotoxic effect through photo-activation with a near-infrared laser. We assessed the anti-cancer properties of AU-011 in vitro utilizing a panel of human cancer cell lines and in vivo using murine subcutaneous and rabbit orthotopic xenograft models of uveal melanoma...
December 14, 2017: Molecular Cancer Therapeutics
https://www.readbyqxmd.com/read/29241325/nanoscale-organic-inorganic-hybrid-photosensitizer-for-highly-effective-photodynamic-cancer-therapy
#7
Jia Chen, Yu Xu, Yu Gao, Dongliang Yang, Fei Wang, Lei Zhang, Biqing Bao, Lianhui Wang
Recently, photodynamic therapy (PDT) has attracted significant attention as a minimally invasive approach for cancer treatment. Clinical applications of current photosensitizers are often limited by their poor water solubility, low singlet oxygen (1O2) quantum yields, long-term toxicity, instability and complex nanostructures. Here we report a rational design of polyhedral oligomeric silsesquioxanes (POSS)-based porphyrin (PPP5000) used as intrinsically nanoscale photosensitizer. In this strategy, inorganic 3D rigid block POSS not only act as anti-aggregate units but also provide conjugating reactive sites for further chemical modification...
December 15, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/29240680/evaluation-on-the-photosensitivity-of-2-2-azobis-2-4-dimethyl-valeronitrile-with-uv
#8
Yi Yang, Yun-Ting Tsai
Azo compounds have high exothermic characteristics and low thermal stability, which have caused many serious thermal accidents around the world. In general, different locations (e.g., equatorial or polar regions) have different UV intensities. If the azo compound exists in an inappropriately stored or transported condition, the decrease in thermal stability may cause a thermal hazard or ageing. 2,2'-Azobis(2,4-dimethyl)valeronitrile (ADVN) is investigated with respect to the thermal stability affected by UV exposure at 0, 6, 12, and 24 h...
December 14, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29240671/microwave-enhanced-photolysis-of-norfloxacin-kinetics-matrix-effects-and-degradation-pathways
#9
Wenchao Liao, Virender K Sharma, Su Xu, Qingsong Li, Lei Wang
Degradation of norfloxacin (NOR) was studied using a combination of microwave and UV irradiation methods (MW/UV process). Remarkable synergistic effect was found between MW and UV light. The removal rate with the MW/UV process was much faster than that with UV light irradiation only. Degradation of NOR followed second-order kinetics and ~72% of NOR could be removed in the first 5 min of MW/UV reaction. Influence of inorganic ions (cations (K⁺, Mg2+, Ca2+, Cu2+) and anions (Cl-, SO₄2-, NO₃-, CO₃2-)), humic acid (HA) and surfactants (cation, anion, and non-ionic) on the degradation of NOR by the MW/UV process was investigated...
December 14, 2017: International Journal of Environmental Research and Public Health
https://www.readbyqxmd.com/read/29240269/reductive-amination-by-photoredox-catalysis-via-polarity-matched-hydrogen-atom-transfer
#10
Xingwei Guo, Oliver S Wenger
Excitation of a Ru(II) photosensitizer in presence of ascorbic acid leads to reduction of iminium ions to electron-rich alpha-aminoalkyl radical intermediates that are rapidly converted to reductive amination products via thiol-mediated hydrogen atom transfer (HAT). As a result, reductive amination of carbonyl compounds with amines via photoredox catalysis proceeds in good to excellent yields and with broad substrate scope, as illustrated by 16 different examples including detailed mechanistic studies. The three key novelties of this work are: (i) the rapid interception of electron-rich radical intermediates by polarity-matched HAT in a photoredox reaction, (ii) the method of reductive amination by photoredox catalysis itself, and (iii) the application of this new method for temporally and spatially controlled reactions on a solid support, as demonstrated by attachment of a fluorescent dye on an activated cellulose support via photoredox-catalyzed reductive amination...
December 14, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/29239123/seeing-the-light-to-change-colour-an-evolutionary-perspective-on-the-role-of-melanopsin-in-neuroendocrine-circuits-regulating-light-mediated-skin-pigmentation
#11
REVIEW
Gabriel E Bertolesi, Sarah McFarlane
Melanopsin photopigments, Opn4x and Opn4m, were evolutionary selected to "see the light" in systems that regulate skin colour change. In this review, we analyze the roles of melanopsins, and how critical evolutionary developments, including the requirement for thermoregulation and ultraviolet protection, the emergence of a background adaptation mechanism in land-dwelling amphibian ancestors, and the loss of a photosensitive pineal gland in mammals, may have helped sculpt the mechanisms that regulate light-controlled skin pigmentation...
December 14, 2017: Pigment Cell & Melanoma Research
https://www.readbyqxmd.com/read/29238991/distribution-and-diversity-of-intrinsically-photosensitive-retinal-ganglion-cells-in-tree-shrew
#12
Elizabeth N Johnson, Teleza Westbrook, Rod Shayesteh, Emily L Chen, Joseph W Schumacher, David Fitzpatrick, Greg D Field
Intrinsically photosensitive retinal ganglion cells (ipRGCs) mediate the pupillary light reflex, circadian entrainment, and may contribute to luminance and color perception. The diversity of ipRGCs varies from rodents to primates, suggesting differences in their contributions to retinal output. To further understand the variability in their organization and diversity across species, we used immunohistochemical methods to examine ipRGCs in tree shrew (Tupaia belangeri). Tree shrews share membership in the same clade, or evolutionary branch, as rodents and primates...
December 14, 2017: Journal of Comparative Neurology
https://www.readbyqxmd.com/read/29236487/the-connection-between-nhc-ligand-count-and-photophysical-properties-in-fe-ii-photosensitizers-an-experimental-study
#13
Peter Zimmer, Lukas Burkhardt, Aleksej Friedrich, Jakob Steube, Adam Neuba, Rahel Schepper, Patrick Müller, Ulrich Flörke, Marina Huber, Stefan Lochbrunner, Matthias Bauer
Four homo- and heteroleptic complexes bearing both polypyridyl units and N-heterocyclic carbene (NHC) donor functions are studied as potential noble metal-free photosensitizers. The complexes [FeII(L1)(terpy)][PF6]2, [FeII(L2)2][PF6]2, [FeII(L1)(L3)][PF6]2, and [FeII(L3)2][PF6]2 (terpy = 2,2':6',2″ terpyridine, L1 = 2,6-bis[3-(2,6-diisopropylphenyl)imidazol-2-ylidene]pyridine, L2 = 2,6-bis[3-isopropylimidazol-2-ylidene]pyridine, L3 = 1-(2,2'-bipyridyl)-3-methylimidazol-2-ylidene) contain tridentate ligands of the C^N^C and N^N^C type, respectively, resulting in a Fe-NHC number between two and four...
December 13, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/29235340/visible-light-promoted-synthesis-of-dibenzofuran-derivatives
#14
Ji Young Cho, Geum-Bee Roh, Eun Jin Cho
Dibenzofurans are naturally-occurring molecules that have received considerable attention for a variety of practical applications, such as in pharmaceuticals and electronic materials. Herein, an efficient and eco-friendly method for the synthesis of dibenzofuran derivatives via intramolecular C-O bond formation, which involves the in situ production of a diazonium salt, is described. The transformation requires a diazotizing agent and is promoted by the use of an organic photosensitizer under visible-light irradiation...
December 13, 2017: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/29235273/-current-status-and-challenging-of-direct-target-study-of-traditional-chinese-medicine-complex-system-based-on-solid-coupling-beads
#15
Ke-Wu Zeng, Peng-Fei Tu
Traditional Chinese medicine(TCM) is a complex system with multiple chemical compositions. The most significant character of TCM is that the chemical compositions interact with each other by multi-target synergism to treat diseases. Previous reports mainly focused on the investigation of single signaling pathway detection or the phenotypic analysis of proteomics difference; however, no studies have been conducted on the identification of direct targets of TCM. Therefore, it is difficult to analyze the molecular mechanism of traditional Chinese medicine from the target source, and it is difficult to explain its traditional efficacy scientifically, thus seriously affecting its clinical application and internationalization...
October 2017: Zhongguo Zhong Yao za Zhi, Zhongguo Zhongyao Zazhi, China Journal of Chinese Materia Medica
https://www.readbyqxmd.com/read/29235031/the-persistence-and-photostabilizing-characteristics-of-benzotriazole-and-5-methyl-1h-benzotriazole-reduce-the-photochemical-behavior-of-common-photosensitizers-and-organic-compounds-in-aqueous-environments
#16
Kenneth Hsien-Yung Chung, Yen-Ching Lin, Angela Yu-Chen Lin
Benzotriazole (BT) and 5-methyl-1H-benzotriazole (5-MeBT) are broadly used in industrial applications, such as anti-icing fluids and dishwashing detergent, and act as the primary building blocks for UV absorbers and photostabilizers. This study examined the occurrence of these two compounds in the environment and their unique photochemical behavior affecting photosensitizers and other micro-organic pollutants in aqueous environments. BT and 5-MeBT were detected in all river water samples from the major rivers in Taipei City in the concentration ranges of 147 to 1560 ng/L and 22 to 235 ng/L, respectively, and both compounds persisted through a conventional wastewater treatment plant...
December 12, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/29232571/investigating-the-excited-state-optical-properties-and-origin-of-large-stokes-shift-in-benz-c-d-indole-n-heteroarene-bf2-dyes-with-ab-initio-tools
#17
Yogesh Gawale, Nagaiyan Sekar
Density Functional Theory and Time Dependent Density Functional Theory computations reveal experimental trends accurately and provide an insight into the origin of red shifted optical spectra, large Stokes shift, nonlinear optical responses and quantitative description of the singlet-triplet energy gap of recently synthesized highly fluorescent membrane permeable benz[c,d]indole N-heteroarene BF2 rigidified BBN and BBC dyes. Our results benchmark the importance of the DFT functionals and polarization functions using the accurate basis set for the calculations of excitation energies, band gaps, dipole moment, non-linear optical properties and geometrical parameters...
December 7, 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/29232113/hyperbranched-polyglycerol-loaded-with-zinc-porphyrins-photosensitizer-release-under-reductive-and-acidic-conditions-for-improved-photodynamic-therapy
#18
Michael H Staegemann, Susanna Gräfe, Burkhard Gitter, Katharina Achazi, Elisa Quaas, Rainer Haag, Arno Wiehe
An adaptable approach toward cleavable nanoparticle carrier systems for photodynamic therapy (PDT) is presented, comprising a biocompatible carrier loaded with multiple photosensitizer (PS) molecules related to the clinically employed PS Temoporfin, two linkers cleavable under different triggers and glyco-targeting with mannose. A synthetic pathway to stimuli responsive hyperbranched polyglycerol (hPG) porphyrin conjugates via the copper(I)-catalyzed 1,3-dipolar cycloaddition (CuAAC) or the strain-promoted alkyne-azide cycloaddition (SPAAC) has been developed...
December 12, 2017: Biomacromolecules
https://www.readbyqxmd.com/read/29232105/a-facile-supramolecular-approach-to-nucleic-acid-driven-activatable-nanotheranostics-that-overcome-drawbacks-of-photodynamic-therapy
#19
Xingshu Li, Sungsook Yu, Dayoung Lee, Gyoungmi Kim, Buhyun Lee, Yejin Cho, Bi-Yuan Zheng, Mei-Rong Ke, Jian-Dong Huang, Ki Taek Nam, Xiaoyuan Chen, Juyoung Yoon
Supramolecular chemistry provides a "bottom-up" method to fabricate nanostructures for biomedical applications. Herein, we report a facile strategy to directly assemble a phthalocyanine photosensitizer (PcS) with an anticancer drug mitoxantrone (MA) to form uniform nanostructures (PcS-MA), which not only display nanoscale optical properties but also have the capability of undergoing nucleic acid-responsive disassembly. These supramolecular assemblies possess activatable fluorescence emission and singlet oxygen generation associated with the formation of free PcS, mild photothermal heating, and a concomitant chemotherapeutic effect associated with the formation of free MA...
December 12, 2017: ACS Nano
https://www.readbyqxmd.com/read/29231936/nitrogen-doped-graphene-quantum-dots-coupled-with-photosensitizers-for-one-two-photon-activated-photodynamic-therapy-based-on-a-fret-mechanism
#20
Jiaheng Sun, Qi Xin, Yang Yang, Hameed Shah, Hongqian Cao, Yanfei Qi, Jian Ru Gong, Junbai Li
A novel material with a large two-photon absorption cross-section was conjugated with a typical photosensitizer for inducing a FRET process. The photosensitizer can be excited by a one-/two-photon laser and then induced photo-toxicity in vitro and in vivo. The system presents great potential for improving treatment depth and the precision of traditional photodynamic therapy.
December 12, 2017: Chemical Communications: Chem Comm
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