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https://www.readbyqxmd.com/read/29050399/diagnostic-criteria-for-chronic-lymphocytic-inflammation-with-pontine-perivascular-enhancement-responsive-to-steroids-clippers
#1
W Oliver Tobin, Yong Guo, Karl N Krecke, Joseph E Parisi, Claudia F Lucchinetti, Sean J Pittock, Jay Mandrekar, Divyanshu Dubey, Jan Debruyne, B Mark Keegan
Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a central nervous system inflammatory syndrome predominantly affecting the brainstem, cerebellum, and spinal cord. Following its initial description, the salient features of CLIPPERS have been confirmed and expanded upon, but the lack of formalized diagnostic criteria has led to reports of patients with dissimilar features purported to have CLIPPERS. We evaluated clinical, radiological and pathological features of patients referred for suspected CLIPPERS and propose diagnostic criteria to discriminate CLIPPERS from non-CLIPPERS aetiologies...
September 1, 2017: Brain: a Journal of Neurology
https://www.readbyqxmd.com/read/29049883/rotational-spectroscopy-of-p-toluic-acid-and-its-1-1-complex-with-water
#2
Elijah G Schnitzler, Nathan A Seifert, Ignes Kusuma, Wolfgang Jaeger
The structure and internal dynamics of p-toluic acid and its 1:1 complex with water were investigated in the gas phase using chirped-pulse and cavity-based Fourier transform microwave spectroscopy. One conformer and one isomer were identified for the monomer and monohydrate, respectively. In the monohydrate, water acts as both a hydrogen bond donor and acceptor, participating in a six-membered intermolecular ring with the carboxyl group. Both a- and b-type transitions were observed for the monomer; only a-type transitions were observed for the monohydrate...
October 19, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/29049882/plasmonic-nanochemistry-based-on-nanohole-array
#3
Bin Ai, Zengyao Wang, Helmuth Möhwald, Gang Zhang
We show that the growth of Ag nanoparticles (NPs) follows the areas of maximum plasmonic field in nanohole arrays (NAs). We thus obtain Ag NP rings not connected to the metallic rim of the nanoholes. The photocatalytic effect resulting from the enhanced E-field of NAs boosts the reaction and is responsible for the site-selectivity. The strategy, using plasmonics to control a chemical reaction, can be expanded to organic reactions, e.g., synthesis of polypyrrole. After removing the NA film, ordered ring-shaped Ag NPs are easily obtained, inspiring a facile micropatterning method...
October 19, 2017: ACS Nano
https://www.readbyqxmd.com/read/29049749/transvalvular-pressure-gradients-for-different-methods-of-mitral-valve-repair-only-neochordoplasty-achieves-native-valve-gradients
#4
Silje Ekroll Jahren, Samuel Hurni, Paul Philipp Heinisch, Bernhard Winkler, Dominik Obrist, Thierry Carrel, Alberto Weber
OBJECTIVES: Many surgical and interventional methods are available to restore patency for patients with degenerative severe mitral valve regurgitation. Leaflet resection and neochordoplasty, which both include ring annuloplasty, are the most frequently performed techniques for the repair of posterior mitral leaflet flail. It is unclear which technique results in the best haemodynamics. In this study, we investigated the effect of different mitral valve reconstruction techniques on mitral valve haemodynamics and diastolic transvalvular pressure gradient in an ex vivo porcine model...
October 3, 2017: Interactive Cardiovascular and Thoracic Surgery
https://www.readbyqxmd.com/read/29049712/easy-technique-for-emergency-fenestration-in-non-fenestrated-fontan-patients
#5
Qiang Fan, Yunfei Ling, Yabo Wang, Qi An
The Fontan procedure is a commonly used final pathway of palliation for single-ventricle physiology. Performing it without fenestration can avoid fenestration-related drawbacks, including subnormal oxygen saturation, decreased exercise tolerance, paradoxical embolization and subsequent need for closure by catheter intervention. If emergency fenestration is required, however, it is not always technically easy to perform, particularly when the atrium is posteriorly located and difficult to expose. We describe an easy technique for creating an anastomosis using a ring-supported polytetrafluoroethylene graft to the atrium for fenestration, performed in 2 patients who underwent extracardiac conduit Fontan procedures without fenestration...
July 13, 2017: Interactive Cardiovascular and Thoracic Surgery
https://www.readbyqxmd.com/read/29049565/a-low-cost-bioprosthetic-semilunar-valve-for-research-disease-modelling-and-surgical-training-applications
#6
Benoit Rosa, Zurab Machaidze, Borami Shin, Sunil Manjila, David W Brown, Christopher W Baird, John E Mayer, Pierre E Dupont
OBJECTIVES: This paper provides detailed instructions for constructing low-cost bioprosthetic semilunar valves for animal research and clinical training. This work fills an important gap between existing simulator training valves and clinical valves by providing fully functioning designs that can be employed in ex vivo and in vivo experiments and can also be modified to model valvular disease. METHODS: Valves are constructed in 4 steps consisting of creating a metal frame, covering it with fabric and attaching a suture ring and leaflets...
August 2, 2017: Interactive Cardiovascular and Thoracic Surgery
https://www.readbyqxmd.com/read/29049549/transapical-cardioscopic-mitral-annuloplasty-a-short-term-survival-study-in-a-porcine-model
#7
Thang Duc Vu, Min Zin Oo, Duc-Viet Nguyen, Ervin Marquez Ocampo, Yilin Ong, Suganya Cheyyatraivendran-Arularasu, Lian-Kah Ti, Mark A Richards, Theo Kofidis
OBJECTIVES: The transapical approach provides concurrent surgical access to the mitral and the aortic valves, the root of the aorta and the left atrium. We previously showed the feasibility of transapical cardioscopic (TAC) surgery in a non-survival porcine model. However, reproducibility and feasibility of ring implantation using TAC have not been reported. Therefore, in this study, we hypothesized that implantation of a mitral annuloplasty ring can be feasibly and safely carried out endoscopically via the apex of the heart...
August 30, 2017: Interactive Cardiovascular and Thoracic Surgery
https://www.readbyqxmd.com/read/29049024/phase-transitions-and-thermal-entanglement-of-the-distorted-ising-heisenberg-spin-chain-topology-of-multiple-spin-exchange-interactions-in-spin-ladders
#8
Hamid Arian Zad, Nerses Ananikian
We consider a symmetric spin-1/2 Ising-XXZ double sawtooth spin ladder obtained from distorting a spin chain, with the XXZ interaction between the interstitial Heisenberg dimers (which are connected to the spins based on the legs via an Ising-type interaction), the Ising coupling between nearest-neighbor spins of the legs and rungs spins, respectively, and additional cyclic four-spin exchange (ring exchange) in the square plaquette of each block. The presented analysis supplemented by results of the exact solution of the model with infinite periodic boundary implies a rich ground state phase diagram...
October 19, 2017: Journal of Physics. Condensed Matter: An Institute of Physics Journal
https://www.readbyqxmd.com/read/29048979/comparison-of-single-port-percutaneous-extraperitoneal-repair-and-three-port-mini-laparoscopic-repair-for-pediatric-inguinal-hernia
#9
Mevlit Korkmaz, Haluk B Güvenç
AIM: Laparoscopy has been widely used in surgical practice in pediatric age, and many techniques for laparoscopic hernia repair have been described till now. In this study, we compared two laparoscopic techniques performed by two surgeons; each surgeon practicing only one of the two techniques. MATERIALS AND METHODS: A retrospective analysis was performed on the surgical charts, enrolling 71 patients with uncomplicated inguinal hernia. Patients were divided into two groups according to the type of surgery: (Group A, 24 patients aged 2 months-8 years) laparoscopic percutaneous internal ring suturing technique and (Group B, 47 patients aged 35 days-12 years) three-port mini-laparoscopic technique...
October 19, 2017: Journal of Laparoendoscopic & Advanced Surgical Techniques. Part A
https://www.readbyqxmd.com/read/29048906/gold-catalyzed-ring-expansion-of-enyne-lactone-generation-and-transformation-of-2-oxoninonium
#10
Kui Luo, Tongxiang Cao, Huanfeng Jiang, Lianfen Chen, Shifa Zhu
An efficient gold-catalyzed ring-expansion reaction of enyne-lactones to form 2-oxoninonium intermediates is reported. The 2-oxoninonium generated in this work could undergo further 6π electrocyclization and aromatization reaction to produce different aromatic compounds.
October 19, 2017: Organic Letters
https://www.readbyqxmd.com/read/29048894/immunomodulatory-polyketides-from-a-phoma-like-fungus-isolated-from-a-soft-coral
#11
Yi-Zhe Sun, Tibor Kurtán, Attila Mándi, Hua Tang, Yalan Chou, Keryea Soong, Li Su, Peng Sun, Chun-Lin Zhuang, Wen Zhang
Fourteen new polyketides with a trans-fused decalin ring system, libertalides A-N (3-16), together with two known analogues, aspermytin A and its acetate (1, 2), were isolated from the fermentation extract of a coral-derived Libertasomyces sp. fungus. Their relative configurations were elucidated on the basis of detailed spectroscopic analysis, and the absolute configurations were determined by TDDFT-ECD and optical rotation (OR) calculations. The OR of 1 and 2 were found to have opposite signs in CH3CN and CHCl3, which was in agreement with the OR calculations producing alternating signs for the optical rotation depending on the applied conditions...
October 19, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/29048892/antiplasmodial-chromanes-and-chromenes-from-the-monotypic-plant-species-koeberlinia-spinosa
#12
Christopher Charles Presley, Ana Lisa Valenciano, Maria L Fernández-Murga, Yongle Du, Narasimhamurthy Shanaiah, Maria B Cassera, Michael Goetz, Jason A Clement, David G I Kingston
Nine new compounds containing either a chromane or chromene ring moiety were isolated from the monotypic plant Koeberlinia spinosa. Compounds 1-4 are chromanes with all possible E and Z isomers of the isoprenoid side chain, with compound 5 a methylated derivative of 1. Compounds 6 and 7 were assigned as diastereomeric cyclized derivatives of 2 and were probably artifacts formed during the extraction or the isolation processes. Compounds 8 and 9 were characterized as new chromenes. Structure elucidation of 1-9 was conducted via 1D and 2D NMR spectroscopic data interpretation, and absolute configurations were determined by ECD spectroscopic analysis...
October 19, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/29048833/-new-c2-symmetric-chiral-stationary-phases-based-on-l-proline-derivatives-as-chains
#13
Long Chen, Lingping Cheng, Shanshan He, Yunchao He, Yaling Wu, Yanxiong Ke, Xinmiao Liang
C2 symmetric chiral compounds overlap themselves when rotating with an axis of 180° with an axis and have important applications in chiral catalysis and chiral separation fields. A novel C2 symmetric stationary phase based on phenyl substituted L-proline derivatives was prepared and compared with the similar stationary phase based on mono-substituted brush-type stationary phase. The C2 symmetric stationary phase showed higher enantiodiscrimination capability than the mono-substituted stationary phase for 31 acidic, neutral and alkaline analytes...
July 8, 2017: Se Pu, Chinese Journal of Chromatography
https://www.readbyqxmd.com/read/29048580/the-impact-of-young-age-on-the-prognosis-for-colorectal-cancer-a-population-based-study-in-taiwan
#14
Chia-Lin Chou, Chien-Jen Tseng, Yow-Ling Shiue
Background: The impact of age as a prognostic factor for patients with colorectal cancer (CRC) remains controversial, possibly due to heterogeneity between studies in terms of patient numbers, percentage of patients undergoing curative resection, percentage of patients receiving neoadjuvant therapy, or failure to adjust for potential confounding factors. This study used colorectal cancer survival data from the Taiwan Cancer Registry database in order to comprehensively analyze age as a prognostic factor...
November 1, 2017: Japanese Journal of Clinical Oncology
https://www.readbyqxmd.com/read/29048398/glucopyranosylidene-spiro-thiazolinones-synthetic-studies-and-determination-of-absolute-configuration-by-tddft-ecd-calculations
#15
Katalin E Szabó, Sándor Kun, Attila Mándi, Tibor Kurtán, László Somsák
Reactions of O-peracylated C-(1-bromo-β-d-glucopyranosyl)formamides with thioamides furnished the corresponding glucopyranosylidene-spiro-thiazolin-4-one. While O-debenzoylations under a variety of conditions resulted in decomposition, during O-deacetylations the addition of MeOH to the thiazolinone moiety was observed, and with EtOH and water similar adducts were isolated or detected. The structure and stereochemistry of the new compounds were established by means of NMR and electronic circular dichroism (ECD) data supported by time-dependent density functional theory ECD (TDDFT-ECD) calculations...
October 19, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29048389/discovery-of-novel-n-substituted-prolinamido-indazoles-as-potent-rho-kinase-inhibitors-and-vasorelaxation-agents
#16
Yangyang Yao, Renze Li, Xiaoyu Liu, Feilong Yang, Ying Yang, Xiaoyu Li, Xiang Shi, Tianyi Yuan, Lianhua Fang, Guanhua Du, Xiaozhen Jiao, Ping Xie
Inhibitors of Rho kinase (ROCK) have potential therapeutic applicability in a wide range of diseases, such as hypertension, stroke, asthma and glaucoma. In a previous article, we described the lead discovery of DL0805, a new ROCK I inhibitor, showing potent inhibitory activity (IC50 6.7 μM). Herein, we present the lead optimization of compound DL0805, resulting in the discovery of 24- and 39-fold more-active analogues 4a (IC50 0.27 μM) and 4b (IC50 0.17 μM), among other active analogues. Moreover, ex-vivo studies demonstrated that 4a and 4b exhibited comparable vasorelaxant activity to the approved drug fasudil in rat aortic rings...
October 19, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29048174/rare-earth-incorporated-tellurotungstate-hybrids-functionalized-by-2-picolinic-acid-ligands-syntheses-structures-and-properties
#17
Qing Han, Yue Wen, Jian-Cai Liu, Wu Zhang, Li-Juan Chen, Jun-Wei Zhao
A series of organic-inorganic rare-earth-incorporated tellurotungstate hybrids, Na4[RE2(H2O)4(pica)2W2O5][(RE(H2O)W2(Hpica)2O4)(B-β-TeW8O30H2)2]2·38H2O (RE = La(III) (1), Ce(III) (2), Nd(III) (3), Sm(III) (4), Eu(III) (5); Hpica = 2-picolinic acid), were prepared via a one-step assembly reaction of Na2WO4·2H2O, RE(NO3)3·6H2O, K2TeO3, Hpica, and triethylamine (tea). Notably, the solubilization of tea toward Hpica and the solubilization of Hpica toward RE cations in the reaction system play an important role in the formation of 1-5...
October 19, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/29048169/photoactivity-of-new-octacationic-magnesium-ii-and-zinc-ii-porphyrazines-in-a-water-solution-and-g-quadruplex-binding-ability-of-differently-sized-zinc-ii-porphyrazines
#18
Fabiola Sciscione, Francesco Manoli, Elisa Viola, Jitendra Wankar, Claudio Ercolani, Maria Pia Donzello, Ilse Manet
The new octacations [(2-Mepy)8PzM](8+) [M = Mg(II)(H2O), Zn(II)], isolated as iodide salts, were obtained from the corresponding neutral complexes [Py8PzM] (Py = 2-pyridyl; Pz = porphyrazinato dianion) upon quaternization with CH3I of the N atoms of the 2-pyridyl rings under mild experimental conditions. The absorption spectra registered in organic solvents as well as in water (H2O) confirm the presence of the complexes in their monomeric form in all cases. The two octacations behave as photosensitizers in a H2O/sodium dodecyl sulfate solution for the production of singlet oxygen, (1)O2, and exhibit quantum yield values (ΦΔ) 2...
October 19, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/29048164/development-of-a-modular-synthetic-route-to-pleuromutilin-12-epi-mutilins-and-related-structures
#19
Mingshuo Zeng, Stephen K Murphy, Seth B Herzon
We describe the development of an enantioselective synthetic route to (+)-pleuromutilin (1), (+)-12-epi-mutilin, and related derivatives. A key hydrindanone was prepared in three steps and 48% overall yield from cyclohex-2-en-1-one. 1,4-Hydrocyanation provided a nitrile (53%, or 85% based on recovered starting material) that was converted to the eneimide 57 in 80% yield by the 1,2-addition of methyllithium to the nitrile function, cyclization, and in situ acylation with di-tert-butyldicarbonate. The eneimide 57 was employed in a two-fold neopentylic coupling reaction with an organolithium reagent derived from the alkyl iodides (R)- or (S)-30, which contain the C11-C13 atoms of the target, to provide diastereomeric diketones in 60% or 48% yield (for coupling with (R)- or (S)-30, respectively)...
October 19, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/29048087/a-diversity-oriented-synthesis-of-natural-product-inspired-molecular-libraries
#20
Jyoti Chauhan, Tania Luthra, Rambabu Gundla, Antonio Ferraro, Ulrike Holzgrabe, Subhabrata Sen
Natural products are the source of innumerable pharmaceutical drug candidates and also form an important aspect of herbal remedies. They are also a source of various bioactive compounds. Herein we have leveraged the structural attributes of several natural products in building a library of architecturally diverse chiral molecules by harnessing R-tryptophan as the chiral auxiliary. It is converted to its corresponding methyl ester 1 which in turn provided a bevy of 1-aryl-tetrahydro-β-carbolines 2a-d, which were then converted to chiral compounds via a diversity oriented synthetic strategy (DOS)...
October 19, 2017: Organic & Biomolecular Chemistry
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