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https://www.readbyqxmd.com/read/28738610/a-novel-donor-%C3%AF-acceptor-type-fluorescence-probe-for-sensing-ph-mechanism-and-application-in-vivo
#1
Jianbin Chao, Huijuan Wang, Yongbin Zhang, Caixia Yin, Fangjun Huo, Kailun Song, Zhiqing Li, Ting Zhang, Yaqin Zhao
A novel pH fluorescent probe 1-(pyren-1-yl)-3-(6-methoxypridin-3-yl)-acrylketone, (PMPA), which had a pyrene structure attached to methoxypyridine, was synthesized for monitoring extremely acidic and alkaline pH. The pH titrations indicated that PMPA displayed a remarkable emission enhancement with a pKa of 2.70 and responded linearly to minor pH fluctuations within the extremely acidic range of 1.26-3.97. Interestingly, PMPA also exhibited strong pH-dependent characteristics with pKa 9.32 and linear response to extreme-alkalinity range of 8...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738574/a-highly-selective-and-sensitive-fluorescent-probe-for-hypochlorous-acid-and-its-lysosome-targetable-biological-applications
#2
Chang Liu, Xiaojie Jiao, Song He, Liancheng Zhao, Xianshun Zeng
A novel lysosome-targetable fluorescence probe PT-1 based on a photoinduced electron transfer (PET) mechanism has been designed and synthesized. For comparison, the probe PT-2 without morpholine moiety as a lysosome-directing group was also synthesized and investigated. Probes PT-1 and PT-2 exhibited high selectivity, high sensitivity (with the detection limits down to the 10(-10)M range) and response in real time (within 10s) toward HOCl over other reactive oxygen species (ROS). Both PT-1 and PT-2 were cell permeable and enabled them to be used for monitoring of HOCl in living cells...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738566/preparation-and-evaluation-of-a-novel-n-benzyl-phenethylamino-%C3%AE-cyclodextrin-bonded-chiral-stationary-phase-for-hplc
#3
Liang Li, Biaoping Cheng, Rendan Zhou, Zhigang Cao, Chun Zeng, Laisheng Li
A novel N-benzyl-phenethylamino-β-cyclodextrin-bonded ordered mesoporous SBA-15 chiral stationary phase (BZCDP) for high-performance liquid chromatography (HPLC) was prepared. The structure and morphology of the ligand and the stationary phase were characterized by mass spectrometry, elemental analysis, infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and thermogravimetric analysis. The enantiomers of chiral compounds including nine common β-adrenergic blocker drugs (β-blockers), eight dansyl amino acids (DNS-AA) and six flavanones were successfully separated by polar organic solvent and reversed-phase chromatography, respectively...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738383/hydralazine-is-a-suitable-mimetic-agent-of-hypoxia-to-study-the-impact-of-hypoxic-stress-on-in-vitro-blood-brain-barrier-model
#4
Morgane Chatard, Clémentine Puech, Nathalie Perek, Frédéric Roche
BACKGROUND/AIMS: Understanding cellular mechanisms induced by hypoxia is fundamental to reduce blood-brain barrier (BBB) disruption. Nevertheless, the investigation of hypoxia on cellular pathways is complex with true hypoxia because HIF-1α has a short lifetime and rapidly reverts back to a normoxic state. To overcome this difficulty, mimetic agents of the hypoxia pathway have been developed, including the gold standard CoCl2. In this study, we proposed to compare CoCl2 and hydralazine in order to determine a suitable mimetic agent of hypoxia for the study on the BBB...
July 24, 2017: Cellular Physiology and Biochemistry
https://www.readbyqxmd.com/read/28738246/crocin-modulates-il-4-il-13-signaling-and-ameliorates-experimentally-induced-allergic-airway-asthma-in-a-murine-model
#5
Haidy Yosri, Wagdi F Elkashef, Eman Said, Nariman M Gameil
Allergic asthma is a chronic respiratory disease with a prevalent T helper (Th2)-mediated immune reaction. Crocin, the major bioactive constituent of saffron, has been reported in multiple studies to have numerous pharmacological activities, including prominent anti-oxidant activities. In the current study, the anti-asthmatic potential of crocin was evaluated. Adult male Swiss Albino mice were administered 10mg of ovalbumin (OVA) mixed with 1mg of aluminum hydroxide intraperitoneally on days 0 and 7 and were administered crocin (25mg/kg) orally daily for 16days...
July 21, 2017: International Immunopharmacology
https://www.readbyqxmd.com/read/28738091/the-second-window-icg-technique-demonstrates-a-broad-plateau-period-for-near-infrared-fluorescence-tumor-contrast-in-glioblastoma
#6
Ryan Zeh, Saad Sheikh, Leilei Xia, John Pierce, Andrew Newton, Jarrod Predina, Steve Cho, MacLean Nasrallah, Sunil Singhal, Jay Dorsey, John Y K Lee
INTRODUCTION: Fluorescence-guided surgery has emerged as a powerful tool to detect, localize and resect tumors in the operative setting. Our laboratory has pioneered a novel way to administer an FDA-approved near-infrared (NIR) contrast agent to help surgeons with this task. This technique, coined Second Window ICG, exploits the natural permeability of tumor vasculature and its poor clearance to deliver high doses of indocyanine green (ICG) to tumors. This technique differs substantially from established ICG video angiography techniques that visualize ICG within minutes of injection...
2017: PloS One
https://www.readbyqxmd.com/read/28737899/%C3%AE-amino-acid-derived-benzimidazole-linked-rhodamines-a-case-of-substitution-effect-at-the-amino-acid-site-toward-spiro-ring-opening-for-selective-sensing-of-al-3-ions
#7
Anupam Majumdar, Subhendu Mondal, Constantin G Daniliuc, Debashis Sahu, Bishwajit Ganguly, Sourav Ghosh, Utpal Ghosh, Kumaresh Ghosh
α-Amino acid derived benzimidazole-linked rhodamines have been synthesized, and their metal ion sensing properties have been evaluated. Experimentally, l-valine- and l-phenylglycine-derived benzimidazole-based rhodamines 1 and 2 selectively recognize Al(3+) ion in aqueous CH3CN (CH3CN/H2O 4/1 v/v, 10 mM tris HCl buffer, pH 7.0) over the other cations by exhibiting color and "turn-on" emission changes. In contrast, glycine-derived benzimidazole 3 remains silent in the recognition event and emphasizes the role of α-substitution of amino acid undertaken in the design...
July 24, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28737892/automated-in-situ-measurement-of-gas-solubility-in-liquids-with-a-simple-tube-in-tube-reactor
#8
Jiisong Zhang, Andrew R Teixeira, Haomiao Zhang, Klavs F Jensen
Gas solubility data in liquids are foundational for assessing a variety of multiphase separations and gas-liquid reactions. Taking advantage of the Tube-in-Tube reactor design built with the semi-permeable Teflon AF-2400 tubes, the liquids are rapidly saturated without direct contacting of gas and liquid. The gas solubility can be determined by performing a steady-state flux balance of both gas and liquid flowing into the reactor system. With this reactor, a fully automated strategy is developed for fast in situ measurement of gas solubility in liquids...
July 24, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28737888/discovery-of-novel-proline-based-neuropeptide-ff-receptor-antagonists
#9
Thuy Nguyen, Ann M Decker, Tiffany L Langston, Kelly M Mathews, Justin N Siemian, Jun-Xu Li, Danni L Harris, Scott P Runyon, Yanan Zhang
The neuropeptide FF (NPFF) system has been implicated in a number of physiological processes including modulating the pharmacological activity of opioid analgesics and several other classes of drugs of abuse. In this study, we report the discovery of a novel proline scaffold with antagonistic activity at the NPFF receptors through a high throughput screening campaign using a functional calcium mobilization assay. Focused structure-activity relationship studies on the initial hit 1 have resulted in several analogs with calcium mobilization potencies in the submicromolar range and modest selectivity for the NPFF1 receptor...
July 24, 2017: ACS Chemical Neuroscience
https://www.readbyqxmd.com/read/28737832/self-assembled-polyprodrug-amphiphile-for-subcutaneous-xenograft-tumor-inhibition-with-prolonged-acting-time-in-vivo
#10
Dong Chen, Yu Huang, Shuting Xu, Huangyong Jiang, Jieli Wu, Xin Jin, Xinyuan Zhu
Polymeric drug delivery system termed as "polyprodrug amphiphile" poly(2-methylacryloyloxyethyl phosphorylcholine)-b-poly(10-hydroxy-camptothecin methacrylate (pMPC-b-pHCPT) is developed for the prolonged-acting cancer therapy. It is obtained by two-step reversible addition-fragmentation chain transfer polymerization of zwitterionic monomer MPC and an esterase-responsive polymerizable prodrug methacrylic anhydride-CPT, respectively. This diblock polymer is composed of both antifouling (pMPC) and bioactive (pHCPT) segments and the drug is designed as a building block to construct the polymer skeleton directly...
July 24, 2017: Macromolecular Bioscience
https://www.readbyqxmd.com/read/28737767/sensitive-and-non-invasive-method-for-the-in-vivo-analysis-of-membrane-permeability-in-small-animals
#11
Andrea Fernandez-Carrera, Eva Vigo, Carla Regueiro-Rodríguez, África González-Fernández, David Olivieri, Luiz S Aroeira
Tissue membranes are boundaries that isolate organs or cavities in the body. These semi-permeable membranes are responsible for passive protection that acts through the regulation of nutrient absorption, secretion and filtration of small molecules. These functions could be altered as a consequence of inflammation or trauma, which in turn could lead to changes in permeability, allowing the entrance of toxins, antigens, proteins or facilitating the spread of tumors. Membrane permeability therefore plays an important role in numerous diseases...
July 24, 2017: Laboratory Investigation; a Journal of Technical Methods and Pathology
https://www.readbyqxmd.com/read/28737761/glutamate-receptor-like-channels-are-essential-for-chemotaxis-and-reproduction-in-mosses
#12
Carlos Ortiz-Ramírez, Erwan Michard, Alexander A Simon, Daniel S C Damineli, Marcela Hernández-Coronado, Jörg D Becker, José A Feijó
Glutamate receptors are well characterized channels that mediate cell-to-cell communication during neurotransmission in animals. Nevertheless, information regarding their functional role in organisms without nervous systems is still limited. In plants, Glutamate Receptor-like (GLR) genes have been implicated in defence against pathogens, reproduction, control of stomata aperture and light signal transduction(1-5). However, the numerous GLR genes present in angiosperm genomes (20 to 70)(6) has prevented the observation of strong phenotypes in loss-of-function mutants...
July 24, 2017: Nature
https://www.readbyqxmd.com/read/28737748/inflammation-free-gas-permeable-lightweight-stretchable-on-skin-electronics-with-nanomeshes
#13
Akihito Miyamoto, Sungwon Lee, Nawalage Florence Cooray, Sunghoon Lee, Mami Mori, Naoji Matsuhisa, Hanbit Jin, Leona Yoda, Tomoyuki Yokota, Akira Itoh, Masaki Sekino, Hiroshi Kawasaki, Tamotsu Ebihara, Masayuki Amagai, Takao Someya
Thin-film electronic devices can be integrated with skin for health monitoring and/or for interfacing with machines. Minimal invasiveness is highly desirable when applying wearable electronics directly onto human skin. However, manufacturing such on-skin electronics on planar substrates results in limited gas permeability. Therefore, it is necessary to systematically investigate their long-term physiological and psychological effects. As a demonstration of substrate-free electronics, here we show the successful fabrication of inflammation-free, highly gas-permeable, ultrathin, lightweight and stretchable sensors that can be directly laminated onto human skin for long periods of time, realized with a conductive nanomesh structure...
July 17, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28737672/mesoporous-silica-nanoparticles-as-drug-delivery-vehicles-in-cancer
#14
REVIEW
Anna Watermann, Juergen Brieger
Even though cancer treatment has improved over the recent decades, still more specific and effective treatment concepts are mandatory. Surgical removal is not always possible, metastases are challenging and chemo- and radiotherapy can not only have severe side-effects but also resistances may occur. To cope with these challenges more efficient therapies with fewer side-effects are required. One promising approach is the use of drug delivery vehicles. Here, mesoporous silica nanoparticles (MSN) are discussed as biodegradable drug carrier to improve efficacy and reduce side-effects...
July 22, 2017: Nanomaterials
https://www.readbyqxmd.com/read/28736757/malaria-parasite-proteins-involved-in-nutrient-channels-at-the-host-erythrocyte-membrane-advances-and-questions-for-future-research
#15
S Chalapareddy, S A Desai
Erythrocytes infected malaria parasites have increased permeability to nutrients and other solutes, as mediated by an unusual ion channel known as the plasmodial surface anion channel (PSAC). Although the increased permeability of infected erythrocytes was identified more than 70 years ago and subsequently characterized with tracer studies, its mechanism and role in parasite biology remained unclear until the introduction of patch-clamp methods and high-throughput screening technologies. These methods discovered and implicated PSAC as the primary mechanism, determined that this channel is essential for parasite development, led to identification of the channel's genes, and stimulated antimalarial drug discovery against this target...
March 2017: Int J Curr Multidiscip Stud
https://www.readbyqxmd.com/read/28736617/an-investigation-of-desalination-by-nanofiltration-reverse-osmosis-and-integrated-hybrid-nf-ro-membranes-employed-in-brackish-water-treatment
#16
M Talaeipour, J Nouri, A H Hassani, A H Mahvi
BACKGROUND: As an appropriate tool, membrane process is used for desalination of brackish water, in the production of drinking water. The present study aims to investigate desalination processes of brackish water of Qom Province in Iran. METHODS: This study was carried out at the central laboratory of Water and Wastewater Company of the studied area. To this aim, membrane processes, including nanofiltration (NF) and reverse osmosis (RO), separately and also their hybrid process were applied...
2017: Journal of Environmental Health Science & Engineering
https://www.readbyqxmd.com/read/28736426/modulation-of-mitochondrial-membrane-potential-and-ros-generation-by-nicotinamide-in-a-manner-independent-of-sirt1-and-mitophagy
#17
Seon Beom Song, So-Young Jang, Hyun Tae Kang, Bie Wei, Un-Woo Jeoun, Gye Soon Yoon, Eun Seong Hwang
Nicotinamide (NAM) plays essential roles in physiology through facilitating NAD+ redox homeostasis. Importantly, at high doses, it protects cells under oxidative stresses, and has shown therapeutic effectiveness in a variety of disease conditions. In our previous studies, NAM lowered reactive oxygen species (ROS) levels and extended cellular life span in primary human cells. In the treated cells, levels of NAD+/NADH and SIRT1 activity increased, while mitochondrial content decreased through autophagy activation...
July 31, 2017: Molecules and Cells
https://www.readbyqxmd.com/read/28735883/permeability-modes-in-fluctuating-lipid-membranes-with-dna-translocating-pores
#18
REVIEW
L H Moleiro, M Mell, R Bocanegra, I López-Montero, P Fouquet, Th Hellweg, J L Carrascosa, F Monroy
Membrane pores can significantly alter not only the permeation dynamics of biological membranes but also their elasticity. Large membrane pores able to transport macromolecular contents represent an interesting model to test theoretical predictions that assign active-like (non-equilibrium) behavior to the permeability contributions to the enhanced membrane fluctuations existing in permeable membranes [Maneville et al. Phys. Rev. Lett. 82, 4356 (1999)]. Such high-amplitude active contributions arise from the forced transport of solvent and solutes through the open pores, which becomes even dominant at large permeability...
July 16, 2017: Advances in Colloid and Interface Science
https://www.readbyqxmd.com/read/28735341/the-effect-of-nanosecond-high-voltage-electric-pulses-on-the-shape-and-permeability-of-polymersome-guvs
#19
Tina Batista Napotnik, Gianluca Bello, Eva-Kathrin Sinner, Damijan Miklavčič
Polymersomes, vesicles composed of block copolymers, are promising candidates as membrane alternatives and functional containers, e.g., as potential carriers for functional molecules because of their stability and tunable membrane properties. In the scope of possible use for membrane protein delivery to cells by electrofusion, we investigated the cytotoxicity of such polymersomes as well as the effects of nanosecond electric pulses with variable repetition rate on the shape and permeability of polymersomes in buffers with different conductivities...
July 22, 2017: Journal of Membrane Biology
https://www.readbyqxmd.com/read/28734512/the-burden-of-enteropathy-and-subclinical-infections
#20
REVIEW
Elizabeth T Rogawski, Richard L Guerrant
Environmental enteropathy is a chronic condition of the small intestine associated with increased intestinal permeability, mucosal inflammation, malabsorption, and systemic inflammation. It is commonly accompanied by enteric infections and is misleadingly considered a subclinical disease. Potential effects of enteric infections and enteropathy on vaccine responses, child growth, cognitive development, and even later life obesity, diabetes, and metabolic syndrome are increasingly being recognized. Herein, we review the evolving challenges to defining environmental enteropathy and enteric infections, current evidence for the magnitude and determinants of its burden, new assessment tools, and relevant interventions...
August 2017: Pediatric Clinics of North America
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