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Christiane Kiske, Svenja Noerenberg, Miriam Ecker, Xingyue Ma, Tohru Taniguchi, Kenji Monde, Wolfgang Eisenreich, Karl-Heinz Engel
The absolute configurations of chiral β-mercaptoalkanones had been previously assigned on the basis of the 1H NMR anisotropy method using (S)-2-methoxy-2-(1-naphthyl)propionic acid ((S)-MαNP) as chiral auxiliary. This study presents a reinvestigation of the configurations of 4-mercapto-2-pentanone, 1, 4-mercapto-2-heptanone, 2, and 2-mercapto-4-heptanone, 3. Enantiomers of 1, 2 and 3 were obtained by lipase-catalyzed hydrolyses of the respective acetylthioalkanones. Upon derivatization with (S)-MαNP, the configurations of the reaction products were deduced on the basis of the order of the HPLC-elution of the diastereoisomeric thioesters assuming that the sector rule previously developed for secondary alcohols is also valid for thiols...
October 25, 2016: Journal of Agricultural and Food Chemistry
Eun-Young Nam, Sun Ah Kim, Heejung Kim, Su-Hyun Kim, Jae-Hyun Han, Ju-Hee Lee, Dong-Il Kim
ETHNOPHARMACOLOGICAL RELEVANCE: Evodiae Fructus (EF) is the dried, unripe fruit of Evodia rutaecarpa Benth., and one of the main components of traditional herbal prescriptions issued for the treatment of sterility caused by irregular menstruation in Korea. However, scientific evidence regarding the efficacy and action mechanism of EF is lacking. AIM OF THE STUDY: In this study, the authors established an in vitro screening tool to identify promising new drug candidates in herbal medicines for the prevention and treatment of premature ovarian failure...
October 18, 2016: Journal of Ethnopharmacology
Julio C Pardo-Novoa, Héctor M Arreaga-González, Mario A Gómez-Hurtado, Gabriela Rodríguez-García, Carlos M Cerda-García-Rojas, Pedro Joseph-Nathan, Rosa E Del Río
The aerial parts of Ageratina glabrata afforded (-)-(3S,4R,5R,6S)-3,5,6-trihydroxy-1-menthene 3-O-β-d-glucopyranoside (1) and (-)-(3S,4S,6R)-3,6-dihydroxy-1-menthene 3-O-β-d-glucopyranoside (3). Acid hydrolysis of 1 yielded (+)-(1R,4S,5R,6R)-1,5,6-trihydroxy-2-menthene (5) and (+)-(1S,4S,5R,6R)-1,5,6-trihydroxy-2-menthene (6), while hydrolysis of 3 yielded (+)-(3S,4S,6R)-3,6-dihydroxy-1-menthene (10), (+)-(1R,4S,6R)-1,6-dihydroxy-2-menthene (11), and (+)-(1S,4S,6R)-1,6-dihydroxy-2-menthene (12). The structures of the new compounds 1, 2, 5-9, and 11 were defined by 1D and 2D NMR experiments, while the absolute configurations of the series of compounds were determined by comparison of the experimental vibrational circular dichroism (VCD) spectra of the 1,6-acetonide 5-acetate derived from 6 and of the 1,6-acetonide derived from 12 with their DFT-calculated spectra...
October 11, 2016: Journal of Natural Products
Cody L Covington, Fernando M S Junior, Jessica H S Silva, Ricardo M Kuster, Mauro B de Amorim, Prasad L Polavarapu
The first natural occurrence in optically active form of the dimeric flavonoid agathisflavone and definition of its axial chirality using chiroptical spectroscopic methods are described. The experimental electronic circular dichroism, electronic dissymmetry factor, optical rotatory dispersion, vibrational circular dichroism (VCD), and vibrational dissymmetry factor spectra of agathisflavone are presented and analyzed with their corresponding quantum chemical predictions to definitively assign the axial chirality of (-)-agathisflavone as (aS)...
October 10, 2016: Journal of Natural Products
Helena Dodziuk, Kenneth Ruud, Tatiana Korona, Taye B Demissie
Density-functional theory and symmetry-adapted perturbation theory calculations on complexes of the enantiomers of CHFClBr with the most stable isomer of C82-3 fullerene show that despite the guests being too large for the host cage, they are nevertheless stabilized by electrostatic interactions. The complexation leads to considerable strain on the cage and the guests accompanied by compression of the bonds of the guest molecule, resulting in considerable complexation-induced changes in the infrared (IR), vibrational circular dichroism (VCD), nuclear magnetic resonance (NMR), and UV-vis spectra...
September 21, 2016: Physical Chemistry Chemical Physics: PCCP
Tommaso Giovannini, Marta Olszowka, Chiara Cappelli
We propose a methodology, based on the combination of classical Molecular Dynamics (MD) simulations with a fully polarizable Quantum Mechanical (QM)/Molecular Mechanics (MM)/Polarizable Continuum Model (PCM) Hamiltonian to calculate Vibrational Circular Dichroism (VCD) spectra of chiral systems in aqueous solution. Polarization effects are included in the MM force field by exploiting an approach based on Fluctuating Charges (FQ). By performing the MD, the description of the solvating environment is enriched by taking into account the dynamical aspects of the solute-solvent interactions...
October 5, 2016: Journal of Chemical Theory and Computation
Lisa Kabelitz, Andrea Nonn, Kay W Nolte, Omid Nikoubashman, Ahmed Othman, Sarah Heringer, Martin Kramer, Martin Wiesmann, Marc A Brockmann
Minipigs are frequently used in (neuro-)interventional research. Longitudinal experiments may require repeated vessel access via the femoral artery. Anticoagulation and incompliance of the animals necessitates the use of a vascular closure device (VCD). The effects of the Angio-Seal VCD in minipigs were longitudinally assessed. Minipig (42±8.4 kg body weight) femoral arteries were sealed using the 8F (n = 6) or 6F (n = 7) Angio-Seal VCD. The pre-interventional femoral artery diameter was 5.1±0.4 mm (4.3-5...
2016: PloS One
Yong Cao, Yuan Zhou, Shuangfei Ni, Tianding Wu, Ping Li, Shenghui Liao, Hong-Bin Lu, Jianzhong Hu
A full understanding of the mechanisms behind spinal cord injury (SCI) processes requires reliable 3D imaging tools for a thorough analysis of changes in angio-spatial architecture. We aimed to employ synchrotron radiation μCT (SRμCT) to characterize 3D temperal-spatial changes in microvasculature post-SCI. Morphometric measurements revealed a significant decrease in vascular volume fraction (VVF), vascular bifurcation density (VBD), vascular segment density (VSD) and vascular connectivity density (VCD) 1 day post-injury, followed by a gradual increase at 3, 7, and 14 days...
September 27, 2016: Journal of Neurotrauma
Sara Gabrieli, Giuseppe Mazzeo, Giovanna Longhi, Sergio Abbate, Tiziana Benincori
Two diastereoisomeric pairs of bis-oxazolines, provided with a stereogenic center at carbon 4 and based on the 3,3'-bithiophene atropisomeric scaffold, were synthesized and structurally characterized. They differ in the substituents at positions 2 and 5 of the thiophene rings, which are functionalized with methyl (1) or phenyl (2) groups, respectively. In vibrational circular dichroism (VCD) spectra, recorded in CCl4 solutions, it is possible to distinctly recognize the characteristic features of axial and central stereogenic elements...
October 2016: Chirality
Kathy Low, Laurence Ruane, Nizam Uddin, Paul Finlay, Kenneth K Lau, Kais Hamza, Peter W Holmes, Garun Hamilton, Philip G Bardin
BACKGROUND: Abnormal vocal cord movements can cause laryngeal extrathoracic airway obstruction (often called vocal cord dysfunction - VCD) leading to asthma-like symptoms. These aberrant movements are characteristically present during inspiration and termed paradoxical vocal cord movement (PVCM). We have reported PVCM in up to 40% of severe asthmatics but it is not known if PVCM is detectable in all patients with asthma-like symptoms and if the condition is more often associated with abnormal lung function...
September 24, 2016: Clinical and Experimental Allergy: Journal of the British Society for Allergy and Clinical Immunology
Amos O Abolaji, Isaac A Adedara, Ayodeji O Abajingin, Ore J Fatunmibi, Emmanuel O Ladipo, Ebenezer O Farombi
4-Vinylcyclohexene diepoxide (VCD) is an occupational chemical widely reported to deplete ovarian follicles in rodents. Here, we investigated VCD-induced reproductive dysfunction in female Wistar rats. The rats were orally administered with VCD (100, 250 and 500mg/kg) for twenty-eight days. Thereafter, we evaluated selected biomarkers of oxidative damage, inflammation, endocrine disruption, and apoptosis. We observed that VCD increased ovarian and uterine malondialdehyde (MDA) level, and catalase, glutathione peroxidase (GPx) and glutathione S-transferase (GST) activities in rats (p<0...
September 16, 2016: Reproductive Toxicology
Stavros Spiliopoulos, Panagiotis Kitrou, Nikolaos Christeas, Dimitris Karnabatidis
PURPOSE: Direct superficial femoral artery (SFA) antegrade puncture is a valid alternative to common femoral artery (CFA) access for peripheral vascular interventions. Data investigating vascular closure device (VCD) hemostasis of distant SFA 6F access are limited. We aimed to investigate the safety and effectiveness of the Starclose SE® VCD for hemostasis, following direct 6F antegrade SFA access distal to the femoral head. METHODS: This prospective, single-center study included patients who were not suitable for CFA puncture and were scheduled to undergo peripheral endovascular interventions using direct antegrade SFA 6F access, at least 2 cm below the inferior edge of femoral head...
September 9, 2016: Diagnostic and Interventional Radiology: Official Journal of the Turkish Society of Radiology
Nils Winkelmann, Max Desole, Inken Hilgendorf, Thomas Ernst, Herbert G Sayer, Christa Kunert, Lars-Olof Mügge, Andreas Hochhaus, Sebastian Scholl
INTRODUCTION: Even in the era of proteasome inhibitors and immunomodulatory drugs, the autologous stem cell transplantation after high-dose melphalan continues to represent a standard approach for myeloma patients in first-line therapy. Different mobilization chemotherapies before stem cell apheresis have been published while cyclophosphamide at a dose level of up to 4 g/m(2) has been evaluated and is commonly applied. In contrast, lower dose levels of cyclophosphamide (e.g., 1.5 g/m(2)) did not result in a sufficient collection of stem cells...
September 17, 2016: Journal of Cancer Research and Clinical Oncology
Lennart van Gils, Joost Daemen, Greg Walters, Todd Sorzano, Todd Grintz, Sam Nardone, Mattie Lenzen, Peter P T De Jaegere, Gary Roubin, Nicolas M Van Mieghem
Catheter-based interventions have become a less invasive alternative to conventional surgical techniques for a wide array of cardiovascular diseases but often create large arteriotomies. A completely percutaneous technique is attractive as it may reduce the overall complication rate and procedure time. Currently, large bore arteriotomy closure relies on suture-based techniques. Access-site complications are not uncommon and often seem related to closure device failure. The MANTA VCD is a novel collagen-based closure device that specifically targets arteriotomies between 10 and 22 Fr...
September 18, 2016: EuroIntervention
Stefano Rigattieri, Alessandro Sciahbasi, Karim Ratib, Alessandro Alonzo, Nicholas Cox, Piotr Chodór, Andrea Berni, Silvio Fedele, Francesco R Pugliese, Christopher J Cooper, Yves Louvard, James Nolan, Sunil V Rao
OBJECTIVES: Periprocedural bleedings, often related to vascular access site, represent an important drawback of percutaneous coronary procedures and are associated with worse outcomes. Radial access (RA) and, potentially, femoral access (FA) with vascular closure device (VCD) are useful strategies in order to mitigate periprocedural bleedings; nevertheless, their relative efficacy is largely undetermined. We aimed to perform a systematic review and meta-analysis of available studies comparing the efficacy of RA and FA with hemostasis by VCD (FA + VCD) on the reduction of access-site complications and/or periprocedural bleedings...
September 15, 2016: Journal of Invasive Cardiology
Sotaro Fukuhara, Hirofumi Tazawa, Hideharu Okanobu, Michiko Kida, Miki Kido, Toshiro Takafuta, Toshihiro Nishida, Hideki Ohdan, Hideto Sakimoto
INTRODUCTION: Extramedullary plasmacytoma (EMP) is a plasma cell neoplasm that presents as a solitary tumor. EMP in the gastrointestinal organs are extremely uncommon. PRESENTATION OF CASE: A 36-year-old man was admitted to our hospital with advanced anemia. He had no specific medical history. Gastroendoscopic findings showed an 8.0-cm submucosal tumor with ulcer on the greater curvature of the gastric body. Fine-needle aspiration was performed, and the pathologic diagnosis of the submucosal tumor was a plasmacytoma...
2016: International Journal of Surgery Case Reports
Nadja Berger, Fee Li, Bert Mallick, J Thomas Brüggemann, Wolfram Sander, Christian Merten
A set of cyclic tetrapeptides of the general form cyclo(Boc-Cys-Pro-X-Cys-OMe) with X being L-/D-Ala, L-/D-Val, and L-/D-Trp was synthesized. These peptides serve as model systems for structure elucidation in solution and feature a variety of structural motifs - namely a β-turn with intramolecular hydrogen bonding interactions, cis/trans isomerism, and a disulphide bond. In this work, we performed a comprehensive structural analysis focussing on their β-turn conformational preferences using NMR, VCD, and Raman spectroscopy...
September 8, 2016: Biopolymers
Roccaldo Sardella, Benedetto Natalini, Federica Ianni, Maura Marinozzi, Antonio Macchiarulo
In response to the outburst of research in the field of synthetic medicinal chemistry, enantioselective chromatography methods based on the use of chiral stationary phases (CSPs) found immediate acceptance as the elective choice for the analytical determinations of the enantiomeric purity of synthetic compounds. In contrast to an initial scepticism, also the preparative-scale applications are gaining increasing recognition as a powerful alternative to enantioselective synthesis for the supply of pure enantiomers of bioactive compounds...
September 7, 2016: Current Medicinal Chemistry
Rung-Chi Li, Umesh Singh, Hugh Porter Windom, Stephen Gorman, Jonathan A Bernstein
BACKGROUND: Diagnosis of VCD is complicated by its symptom similarities to asthma. Although clinical history, spirometry, and fiberoptic nasolaryngoscopy are used for VCD diagnosis, videostroboscopy is considered the gold standard. However, little is know about patient characteristics that might suggest a VCD diagnosis is more likely. OBJECTIVE: To identify clinical characteristics of patients suspected of having VCD that would increase the likelihood of an accurate diagnosis before videostroboscopy...
October 2016: Annals of Allergy, Asthma & Immunology
Yutaka Okazaki, Thierry Buffeteau, Elise Siurdyban, David Talaga, Naoya Ryu, Ryohei Yagi, Emilie Pouget, Makoto Takafuji, Hirotaka Ihara, Reiko Oda
Synthesis of chiral inorganic or hybrid nanomaterials through sol-gel transcription of chiral organic templates has attracted a great deal of interest for more than a decade. However, the chiral nature of these inorganic matrices has never been directly observed. For the first time, we report a direct evaluation of chirality on noncrystalline silica chiral nanoribbons by vibrational circular dichroism (VCD) measurements. Strong Cotton effect around 1150-1000 cm(-1) from Si-O-Si asymmetric stretching vibration was observed...
October 12, 2016: Nano Letters
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