Read by QxMD icon Read

Pre-organized ligand

Michał Nowakowski, Joanna Czapla-Masztafiak, Igor Zhukov, Lilia Zhukova, Maciej Kozak, Wojciech M Kwiatek
Human prion protein is a subject of extensive study, related in particular to the molecular basis of neurodegenerative disease development and prevention. This protein has two main domains: the membrane C-terminal, structured domain as well as the unstructured N-terminal domain. While PrPC (23-231) has up to eight Cu(ii) binding sites in the N-terminal domain, it includes a characteristic, conservative octarepeat region PHGGGWGQ, which was studied by means of X-ray absorption near edge spectroscopy. The measurements were conducted at the SuperXAS beamline (SLS, PSI, Villigen)...
February 13, 2019: Metallomics: Integrated Biometal Science
Colm Healy, Friedrich W Steuber, Paul Wix, Lauren K Macreadie, Amal Cherian Kathalikkattil, Wolfgang Schmitt
Polyoxometalates (POMs) are commonly prepared using a "bottom-up" synthetic procedure. The alternative "top-down" approach of disassembling a pre-formed POM unit to generate new synthetic intermediates is promising, but relatively comparatively underused. In this paper, a rationale for the top-down method is provided, demonstrating that this approach can generate compounds that are fundamentally inaccessible from simple bottom-up assembly. We demonstrate this principle through the synthesis of a series of 10, new, mixed-metal, hybrid compounds with the general formula [TBA]2[MoVI10CoII6O30(RpPO3)6(RcCOO)2(L)x(H2O)6] (TBA = tetrabutylammonium, Rp = phosphonate moiety, Rc = carboxylate moiety, L = pyridyl ligand, and x = 2-4), including a one-dimensional polyoxometalate-based coordination polymer...
February 12, 2019: Dalton Transactions: An International Journal of Inorganic Chemistry
Francesca Ferrua, Stefania Galimberti, Virginie Courteille, Mary Anne Slatter, Claire Booth, Despina Moshous, Benedicte Neven, Stephane Blanche, Alexandra Laberko, Anna Shcherbina, Dmitry Balashov, Elena Soncini, Fulvio Porta, Hamoud Al-Mousa, Bandar Al-Saud, Hasan Al-Dhekri, Rand Arnaout, Renata Formankova, Yves Bertrand, Andrzej Lange, Joanne Smart, Beata Wolska-Kusnierz, Victor M Aquino, Christopher C Dvorak, Anders Fasth, Fanny Fouyssac, Carsten Heilmann, Manfred Hoenig, Catharina Schuetz, Jadranka Kelečić, Robbert G M Bredius, Arjan C Lankester, Caroline A Lindemans, Felipe Suarez, Kathleen E Sullivan, Michael H Albert, Krzysztof Kałwak, Vincent Barlogis, Monica Bhatia, Victoria Bordon, Wojciech Czogala, Laura Alonso, Figen Dogu, Jolanta Gozdzik, Aydan Ikinciogullari, Gergely Kriván, Per Ljungman, Isabelle Meyts, Peter Mustillo, Angela R Smith, Carsten Speckmann, Mikael Sundin, Steven John Keogh, Peter John Shaw, Jaap Jan Boelens, Ansgar S Schulz, Petr Sedlacek, Paul Veys, Nizar Mahlaoui, Ales Janda, E Graham Davies, Alain Fischer, Morton J Cowan, Andrew Richard Gennery
BACKGROUND: CD40 ligand (CD40L) deficiency, an X-linked primary immunodeficiency, causes recurrent sinopulmonary, Pneumocystis and Cryptosporidium infections. Long-term survival with supportive therapy is poor. Currently, the only curative treatment is hematopoietic stem cell transplantation (HSCT). OBJECTIVE: We performed an international collaborative study to improve patients' management, aiming to individualize risk factors and determine optimal HSCT characteristics...
January 17, 2019: Journal of Allergy and Clinical Immunology
Sandeep R Vemula, Michael R Chhoun, Gregory R Cook
Over the past few decades, transition metal catalysis has witnessed a rapid and extensive development. The discovery and development of cross-coupling reactions is considered to be one of the most important advancements in the field of organic synthesis. The design and synthesis of well-defined and bench-stable transition metal pre-catalysts provide a significant improvement over the current catalytic systems in cross-coupling reactions, avoiding excess use of expensive ligands and harsh conditions for the synthesis of pharmaceuticals, agrochemicals and materials...
January 9, 2019: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Susmita Roy, Scott P Hennelly, Heiko Lammert, José N Onuchic, Karissa Y Sanbonmatsu
Investigations of most riboswitches remain confined to the ligand-binding aptamer domain. However, during the riboswitch mediated transcription regulation process, the aptamer domain and the expression platform compete for a shared strand. If the expression platform dominates, an anti-terminator helix is formed, and the transcription process is active (ON state). When the aptamer dominates, transcription is terminated (OFF state). Here, we use an expression platform switching experimental assay and structure-based electrostatic simulations to investigate this ON-OFF transition of the full length SAM-I riboswitch and its magnesium concentration dependence...
January 3, 2019: Nucleic Acids Research
Emily Sempou, Osaamah Ali Lakhani, Sarah Amalraj, Mustafa K Khokha
Congenital heart disease (CHD) is the most common birth defect, yet its genetic causes continue to be obscure. Fibroblast growth factor receptor 4 ( FGFR4 ) recently emerged in a large patient exome sequencing study as a candidate disease gene for CHD and specifically heterotaxy. In heterotaxy, patterning of the left-right (LR) body axis is compromised, frequently leading to defects in the heart's LR architecture and severe CHD. FGF ligands like FGF8 and FGF4 have been previously implicated in LR development with roles ranging from formation of the laterality organ [LR organizer (LRO)] to the transfer of asymmetry from the embryonic midline to the lateral plate mesoderm (LPM)...
2018: Frontiers in Physiology
Tasneem Gul Kazi, Hassan Imran Afridi, Murk Bhatti, Asma Akhtar
An innovative ultrasonic assisted microextraction method using a deep eutectic solvent for entrapping the organ metallic complexes was developed to pre-concentrate the trace quantities of cadmium (Cd) and lead (Pb) in lipsticks and eye shadows of different brands prior to flame atomic absorption spectrometry analysis. A deep eutectic solvent (DES) was used in this study, prepared by mixing metal salt (ZnCl2 ) and hydrogen bond donors such as (acetamide) in different ratio. The different branded cosmetic items, lipstick and eye shadows, obtained from local market and subjected to acid digestion prior to application of proposed ultrasonic assisted microextraction method based on deep eutectic solvent (UAµE-DES) with the aid of mechanical and ultrasound energies...
March 2019: Ultrasonics Sonochemistry
Mark B Pepys
The phylogenetically ancient, pentraxin family of plasma proteins, comprises C-reactive protein (CRP) and serum amyloid P component (SAP) in humans and the homologous proteins in other species. They are composed of five, identical, non-covalently associated protomers arranged with cyclic pentameric symmetry in a disc-like configuration. Each protomer has a calcium dependent site that mediates the particular specific ligand binding responsible for all the rigorously established functional properties of these proteins...
2018: Frontiers in Immunology
Colt R Heathman, Travis S Grimes, Santa Jansone-Popova, Santanu Roy, Vyacheslav S Bryantsev, Peter Zalupski
Thermodynamic influence of a pre-organized N-donor group on the coordination of trivalent actinides and lanthanides by an aminopolycarboxylate aqueous complexant was investigated. The synthesized reagent N-2-methylpicolinate-ethylenediamine-N,N',N'-triacetic acid, EDTA-Mpic, resembles ethylenediamine-N,N,N',N'-tetraacetic acid, EDTA, with a single acetate pendant arm replaced for a 6-carboxypyridin-2-yl-methyl group. The rigidified N-donor picolinate functionality shows a profound impact on ligand protonation and trivalent f-element complexation equilibria as demonstrated using potentiometric, spectroscopic, liquid-liquid metal partitioning studies and molecular dynamics calculations...
November 15, 2018: Chemistry: a European Journal
Roser Vento-Tormo, Mirjana Efremova, Rachel A Botting, Margherita Y Turco, Miquel Vento-Tormo, Kerstin B Meyer, Jong-Eun Park, Emily Stephenson, Krzysztof Polański, Angela Goncalves, Lucy Gardner, Staffan Holmqvist, Johan Henriksson, Angela Zou, Andrew M Sharkey, Ben Millar, Barbara Innes, Laura Wood, Anna Wilbrey-Clark, Rebecca P Payne, Martin A Ivarsson, Steve Lisgo, Andrew Filby, David H Rowitch, Judith N Bulmer, Gavin J Wright, Michael J T Stubbington, Muzlifah Haniffa, Ashley Moffett, Sarah A Teichmann
During early human pregnancy the uterine mucosa transforms into the decidua, into which the fetal placenta implants and where placental trophoblast cells intermingle and communicate with maternal cells. Trophoblast-decidual interactions underlie common diseases of pregnancy, including pre-eclampsia and stillbirth. Here we profile the transcriptomes of about 70,000 single cells from first-trimester placentas with matched maternal blood and decidual cells. The cellular composition of human decidua reveals subsets of perivascular and stromal cells that are located in distinct decidual layers...
November 2018: Nature
M Lakshmi Kantam, Chandrakanth Gadipelly, Gunjan Deshmukh, K Rajender Reddy, Suresh Bhargava
Activation of C-H bonds and their application in cross coupling chemistry has received a wider interest in recent years. The conventional strategy in cross coupling reaction involves the pre-functionalization step of coupling reactants such as organic halides, pseudo-halides and organometallic reagents. The C-H activation facilitates a simple and straight forward approach devoid of pre-functionalization step. This approach also addresses the environmental and economical issues involved in several chemical reactions...
October 30, 2018: Chemical Record: An Official Publication of the Chemical Society of Japan ... [et Al.]
Diamantoula Maniaki, Evangelos Pilichos, Spyros P Perlepes
The area of 3d-metal coordination clusters that behave as Single-Molecule Magnets (SMMs) is now quite mature within the interdisciplinary field of Molecular Magnetism. This area has created a renaissance in Inorganic Chemistry. From the synthetic Inorganic Chemistry viewpoint, the early years of "try and see" exercises (1993-2000) have been followed by the development of strategies and strict approaches. Our review will first summarize the early synthetic efforts and routes for the preparation of polynuclear 3d-metal SMMs, and it will be then concentrated on the description of the existing strategies...
2018: Frontiers in Chemistry
Younghoon Kim, Jaehyoung Koo, In-Chul Hwang, Rahul Dev Mukhopadhyay, Soonsang Hong, Jejoong Yoo, Ajaz Ahmad Dar, Ikjin Kim, Dohyun Moon, Tae Joo Shin, Young Ho Ko, Kimoon Kim
We report a new approach to building hierarchical superstructures using a shape-persistent porous organic cage, which acts as a premade secondary building unit, and coordination chemistry. To illustrate the principle, a zinc-metalated porphyrin box (Zn-PB), a corner-truncated cubic porous cage, was connected by suitable dipyridyl terminated bridging ligands to construct PB-based hierarchical superstructures (PSSs). The PSSs were stabilized not only by the coordination bonds between Zn ions and bipyridyl-terminated ligands but also by π-π interactions between the corners of the Zn-PB units...
October 3, 2018: Journal of the American Chemical Society
Walhan Alshaer, Hervé Hillaireau, Elias Fattal
Aptamers are versatile nucleic acid-based macromolecules characterized by their high affinity and specificity to a specific target. Taking advantage of such binding properties, several aptamers have been selected to bind tumor biomarkers and have been used as targeting ligands for the functionalization of nanomedicines. Different functionalization methods have been used to link aptamers to the surface drug nanocarriers. The pre-clinical data of such nanomedicines overall show an enhanced and selective delivery of therapeutic payloads to cancer cells, thereby accelerating steps towards more effective therapeutic systems...
September 27, 2018: Advanced Drug Delivery Reviews
Andrew Oliphant, Jodi L Alexander, Martin T Swain, Simon G Webster, David C Wilcockson
BACKGROUND: Ecdysis is an innate behaviour programme by which all arthropods moult their exoskeletons. The complex suite of interacting neuropeptides that orchestrate ecdysis is well studied in insects, but details of the crustacean ecdysis cassette are fragmented and our understanding of this process is comparatively crude, preventing a meaningful evolutionary comparison. To begin to address this issue we identified transcripts coding for neuropeptides and their putative receptors in the central nervous system (CNS) and Y-organs (YO) within the crab, Carcinus maenas, and mapped their expression profiles across accurately defined stages of the moult cycle using RNA-sequencing...
September 26, 2018: BMC Genomics
Kerstin B Ksionzek, Jing Zhang, Kai-Uwe Ludwichowski, Dorothee Wilhelms-Dick, Scarlett Trimborn, Thomas Jendrossek, Gerhard Kattner, Boris P Koch
Dissolved organic matter (DOM) is ubiquitous in natural waters and plays a central role in the biogeochemistry in riverine, estuarine and marine environments. This study quantifies and characterizes solid-phase extractable DOM and trace element complexation at different salinities in the Weser and Elbe River, northern Germany, and the North Sea. Dissolved organic carbon (DOC), total dissolved nitrogen (TDN), Co and Cu concentrations were analyzed in original water samples. Solid-phase extracted (SPE) water samples were analyzed for DOC (DOCSPE), dissolved organic nitrogen (DONSPE), sulfur (DOSSPE) and trace metal (51V, 52Cr, 59Co, 60Ni, 63Cu, 75As) concentrations...
2018: PloS One
Pradeep Manuneedhi Cholan, Siân P Cartland, Lei Dang, Benjamin S Rayner, Sanjay Patel, Shane R Thomas, Mary M Kavurma
The vascular endothelium is critical for maintenance of cardiovascular homeostasis. Endothelial dysfunction is a key event of atherosclerosis, with oxidative stress mediated by reactive oxygen species (ROS) playing a major role. Tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is increasingly recognised to play a protective role in atherosclerosis, however the molecular mechanisms by which it exerts its beneficial effects are unclear. Here we examined if TRAIL could attenuate vascular oxidative stress and improve endothelial cell (EC) function...
October 2018: Free Radical Biology & Medicine
Halis Kaan Akturk, Aimon Alkanani, Zhiyuan Zhao, Liping Yu, Aaron W Michels
Context: Immune checkpoint inhibitors, including monoclonal antibodies directed against programmed cell death protein 1 (PD-1) and its ligand, have emerged as beneficial cancer immunotherapies. These therapies are known to cause immune-related side effects; however, their role in patients with a preexisting autoimmune disease is not clear. Case Description: We describe two cases of anti-PD-1 immune-related adverse events. A 52-year-old male with longstanding type 1 diabetes (T1D), long-term stable kidney transplant, and hypothyroidism received two separate anti-PD-1 monoclonal antibodies for metastatic melanoma...
October 1, 2018: Journal of Clinical Endocrinology and Metabolism
Zhongwei Liu, Yuan Wang, Haitao Zhu, Chuan Qiu, Gongchang Guan, Junkui Wang, Yan Guo
Vascular smooth muscle cells (VSMCs) contractile- synthetic phenotypic conversion takes responsibility in the atherosclerotic plaque formation by abnormal synthesis, secretion and deposition of extracellular matrix (ECM). Matrine exerts therapeutic effects on both cardiovascular diseases and organ fibrosis. In this study, we investigated matrine's inhibitory effect and mechanisms on AGEs- induced VSMC contractile- synthetic phenotypic conversion. Cultured human coronary smooth muscle cells (HCSMCs) were exposed to AGEs...
September 15, 2018: European Journal of Pharmacology
Zhenbo Mo, Arseni Kostenko, Yu-Peng Zhou, Shenglai Yao, Matthias Driess
The first N-heterocyclic silylene (NHSi)-silane scaffold LSi-R-Si(H)Mes2 (1) (L=PhC(NtBu)2 ; R=1,12-xanthendiyl spacer; Mes=2,4,6-Me3 C6 H2 ) was synthesized and used to form the unique rhodium(III) complex (LSi-R-SiMes2 )Rh(H)Cl 2 through its reaction with 0.5 molar equivalents of [Rh(coe)2 Cl]2 (coe=cyclooctene). An X-ray diffraction analysis revealed that 2 has a (SiII SiIV )Rh(H)Cl core with three short Rh⋅⋅⋅H-C contacts with Me groups of the ligand 1, which cause a distorted pentagonal bipyramidal coordination of the Rh center...
October 1, 2018: Chemistry: a European Journal
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"