Read by QxMD icon Read


Dillys van Vliet, Agnieszka Smolinska, Quirijn Jöbsis, Jean Muris, Philippe Rosias, Jan Dallinga, Edward Dompeling, Frederik van Schooten
Background Asthma control falls short of current goals of asthma management guidelines. Non-invasive monitoring of airway inflammation may help to improve the level of asthma control in children. Aim 1) To identify a set of exhaled volatile organic compounds (VOCs) that is most predictive for an asthma exacerbation in children. 2) To determine the chemical background of predictive VOCs. Methods In an one-year prospective observational study, 96 asthmatic children were studied . At clinical visits with an interval of 2 months, asthma control, fractional exhaled nitric oxide, lung function (FEV1, FEV1/VC) and VOCs in exhaled breath were determined by means of gas chromatography time-of-flight mass spectrometry...
January 19, 2017: Journal of Breath Research
Bo Song, Chang-Bin Yu, Yue Ji, Mu-Wang Chen, Yong-Gui Zhou
A novel palladium-catalyzed intramolecular reductive amination of ketones with weakly nucleophilic sulfonamides has been developed in the presence of a Brønsted acid, giving a wide range of chiral γ-, δ-, and ε-sultams in high yields and up to 99% of enantioselectivity.
January 19, 2017: Chemical Communications: Chem Comm
Kalliopi Sofou, Maria Dahlin, Tove Hallböök, Marie Lindefeldt, Gerd Viggedal, Niklas Darin
OBJECTIVES: Our aime was to study the short- and long-term effects of ketogenic diet on the disease course and disease-related outcomes in patients with pyruvate dehydrogenase complex deficiency, the metabolic factors implicated in treatment outcomes, and potential safety and compliance issues. METHODS: Pediatric patients diagnosed with pyruvate dehydrogenase complex deficiency in Sweden and treated with ketogenic diet were evaluated. Study assessments at specific time points included developmental and neurocognitive testing, patient log books, and investigator and parental questionnaires...
January 18, 2017: Journal of Inherited Metabolic Disease
Hai-Tao Qin, Shu-Wei Wu, Jia-Li Liu, Feng Liu
A redox-neutral, mild, and simple protocol is developed for the synthesis of α-trifluoromethylated ketones from vinyl azides under transition-metal-free conditions. In the presence of organic photoredox catalyst N-methyl-9-mesityl acridinium and sodium trifluoromethanesulfinate, a broad range of substituted vinyl azides were found to react smoothly upon visible-light irradiation, readily furnishing the corresponding products in satisfied yields.
January 19, 2017: Chemical Communications: Chem Comm
Rajaka Lingayya, Mari Vellakkaran, Kommu Nagaiah, Prabhakar Rao Tadikamalla, Jagadeesh Babu Nanubolu
An efficient Pd(ii)-catalyzed direct O-alkenylation of 2-arylquinazolinones with simple ketone-derived N-tosylhydrazones is reported. In this reaction, O-alkenylquinazolines were obtained in good yields, with excellent functional group tolerance. Pd-carbene migratory insertion is proposed as the key step in the reaction mechanism.
January 19, 2017: Chemical Communications: Chem Comm
Xiaomeng Wang, Qi Liu, Jian Zhou, Xiuhua Wu, Qingan Zhu
A high-fat, low-carbohydrate diet (KD) or calorie restriction in the form of every-other-day fasting (EODF) results in ketone body metabolism with an increasing β-hydroxybutyrate (βOHB) level. Previous studies have supported that a KD and EODF have a neuroprotective effect. However, the βOHB levels in the cerebrospinal fluid (CSF) resulting from a KD and EODF remain unknown. The aim of this study was to detect βOHB levels in rats fed a KD, EODF diet, and every-other-day ketogenic diet (EODKD) and to compare the serum βOHB level with the CSF βOHB level...
January 19, 2017: Experimental Animals
Kai-Min Yang, Ming-Ching Cheng, Chih-Wei Chen, Chin-Yin Tseng, Li-Yun Lin, Po-Yuan Chiang
Algae oil and fish oil are n-3 PUFA mainstream commercial products. The various sources for the stability of n-3 PUFA oxidation are influenced by the fatty acid composition, extraction and refined processing. In this study, the oil stability index (OSI) occurs within 2.3 to 7.6 hours with three different n-3 PUFA rich oil. To set the OSI in the Rancimat test as the oil stability limit and observed various degrees of oxidation (0, 25, 50, 75, 100 and 125%). The volatile oxidation compounds were analyzed via headspace-solid phase microextraction (HS-SPME) and GC/MS...
January 18, 2017: Journal of Oleo Science
Robert J Pawlosky, Martin F Kemper, Yoshihero Kashiwaya, M Todd King, Mark P Mattson, Richard L Veech
In patients with Alzheimer's disease (AD) and in a triple transgenic (3xTgAD) mouse model of AD low glucose metabolism in the brain precedes loss of memory and cognitive decline. The metabolism of ketones in the brain by-passes glycolysis and therefore may correct several deficiencies that are associated with glucose hypometabolism. A dietary supplement composed of an ester of D-β-hydroxybutyrate and R-1,3 butane diol referred to as ketone ester (KE) was incorporated into a rodent diet and fed to 3xTgAD mice for 8 months...
January 18, 2017: Journal of Neurochemistry
Hongyu Qiu, Aleksandra Novikov, Volker Vallon
Inhibitors of the sodium-glucose cotransporter SGLT2 are a new class of anti-hyperglycemic drugs that have been approved for the treatment of type 2 diabetes mellitus (T2DM). These drugs inhibit glucose reabsorption in the proximal tubules of the kidney thereby enhancing glucosuria and lowering blood glucose levels. Additional consequences and benefits include a reduction in body weight, uric acid levels, and blood pressure. Moreover, SGLT2 inhibition can have protective effects on the kidney and cardiovascular system in patients with T2DM and high cardiovascular risk...
January 18, 2017: Diabetes/metabolism Research and Reviews
Toshifumi Morioka, Akihiro Nishizawa, Takayuki Furukawa, Mamoru Tobisu, Naoto Chatani
Despite advances in methods for the decarbonylation of aldehydes, the decarbonylation of ketones has met with limited success be-cause this process requires the activation of two inert carbon-carbon bonds. All of the decarbonylation reactions of simple unstained ketones reported to date require the addition of a stoichiometric rhodium complex. We report herein the nickel/N-heterocyclic car-bene-mediated decarbonylation of simple diary ketones. This reac-tion shows unique acceleration effects based on the presence of both electron-donating and electron-withdrawing groups...
January 18, 2017: Journal of the American Chemical Society
Pedro Francisco Brandão, Rui Miguel Ramos, Paulo Joaquim Ferreira de Almeida, Jose António Rodrigues
A new approach is proposed for the extraction and determination of carbonyl compounds in solid samples, like wood or cork materials. Cork products are used as building materials due to its singular characteristics; however little is known about its aldehyde emission potential and content. Sample preparation was done by using a gas-diffusion microextraction (GDME) device, for the direct extraction of volatile aldehydes and derivatization with 2,4-dinitrophenylhydrazine. Analytical determination of the extracts was done by HPLC-UV, with detection at 360 nm...
January 18, 2017: Journal of Agricultural and Food Chemistry
Jing Liu, Nils Arneborg, Torben B Toldam-Andersen, Mikael A Petersen, Wender L P Bredie
BACKGROUND: There has been increasing interest in the use of selected non-Saccharomyces yeasts in co-culture with Saccharomyces cerevisiae. In this work, three non-Saccharomyces yeast strains (Metschnikowia viticola, Metschnikowia fructicola and Hanseniaspora uvarum) indigenously isolated in Denmark, were used in sequential fermentations with S. cerevisiae on three cool-climate grape cultivars Bolero, Rondo and Regent. During the fermentations, the yeast growth was determined as well as key oenological parameters, volatile compounds and sensory properties of finished rosé wines...
January 18, 2017: Journal of the Science of Food and Agriculture
Wei Shu, Cristina Nevado
A redox-neutral, light-mediated functionalization of unactivated C(sp(3) )-H bonds via iminyl radicals is presented here. A 1,5-H transfer followed by the functionalization of a C(sp(2) )-H bond takes place in aqueous media producing a variety of elaborated fused ketones. Mechanistic investigations have revealed 1,5-H transfer as the reversible, rate-determining step in this transformation. Divergent scaffolds are also accessible via C(sp(3) )-N bond formation upon a careful choice of the reaction additives...
January 18, 2017: Angewandte Chemie
Mehmet Fatih Aycan, Tolga Tolunay, Teyfik Demir, Mesut Emre Yaman, Yusuf Usta
Aim of this study is to assess the pullout performance of various pedicle screws in different test materials. Polyurethane foams (Grade 10 and Grade 40) produced in laboratory and bovine vertebrae were instrumented with normal, cannulated (cemented), novel expandable and normal (cemented) pedicle screws. Test samples were prepared according to the ASTM F543 standard testing protocols and surgical guidelines. To examine the screw placement and cement distribution, anteriosuperior and oblique radiographs were taken from each sample after insertion process was completed...
January 1, 2017: Proceedings of the Institution of Mechanical Engineers. Part H, Journal of Engineering in Medicine
Isai Ramakrishna, Vinod Bhajammanavar, Sumitava Mallik, Mahiuddin Baidya
A practical and step-economical nitroso aldol reaction has been developed based on metal-free direct cross-coupling of ready-stock anilines with silyl enol ethers at room temperature affording α-amino ketones in high yields (up to 82%). The protocol features a one-pot cascade of nitroso compound generation, selective C-N bond formation, and N-O bond cleavage using solely inexpensive and user-friendly Oxone and displays remarkable functional group tolerance. The method was further extended to prepare densely functionalized indoles that are otherwise difficult to synthesize...
January 17, 2017: Organic Letters
Elisabetta Brenna, Michele Crotti, Francesco Gilberto Gatti, Ludovico Marinoni, Daniela Monti, Sara Quaiato
Enantiopure 2-methyl-3-substituted tetrahydrofurans are key precursors of several biologically active products (drugs, flavors and agrochemicals). Thus, a stereocontrolled and efficient methodology for the obtainment of these synthons is highly desirable. We exploited a two-steps multienzymatic stereoselective cascade reduction of α-bromo-α,β-unsaturated ketones to give the corresponding bromohydrins in good yields, with high ee and de values. The cascade process is catalyzed by an ene-reductase and an alcohol dehydrogenase...
January 17, 2017: Journal of Organic Chemistry
Jiang Meng, Min Wen, Shiwei Zhang, Peiwen Pan, Xingxin Yu, Wei-Ping Deng
A practical and efficient method for divergent synthesis of 3,6-disubstituted- and 3,5,6-trisubstituted-1,2,4-triazines via unexpected rhodium-catalyzed O-H insertion/rearrangement/conditions-controlled intramolecular cyclization and oxidation reaction under mild conditions has been developed. Notably, it is the first example for the synthesis of 1,2,4-triazines with different substituted-patterns via a common intermediate with excellent chemoselectivities by the reaction of N-acylhydrazones as aze-[3C] or [4C] synthons with N-sulfonyl-1,2,3-triazoles as aze-[2C] synthons...
January 17, 2017: Journal of Organic Chemistry
Matteo Vergati, Eriseld Krasniqi, Girolamo Del Monte, Silvia Riondino, Doriana Vallone, Fiorella Guadagni, Patrizia Ferroni, Mario Roselli
Pre-clinical and clinical studies have investigated the role of a dysregulated metabolism in the sustainability of tumor initiation and progression. One of the most familiar metabolic alterations encountered in several types of cancers is the upregulation of glycolysis, which is also maintained in conditions of normal oxygen tension (aerobic glycolysis, Warburg effect) while oxidative phosphorylation is apparently reduced. As a result, cancer cells convert most incoming glucose to lactate. Although more rapid, adenosine triphosphate (ATP) production by glycolysis is less efficient in terms of ATP generated per unit of glucose consumed than oxidative phosphorylation...
January 16, 2017: Current Medicinal Chemistry
Jianfei Yu, Jiao Long, Yuhong Yang, Weilong Wu, Peng Xue, Lung Wa Chung, Xiu-Qin Dong, Xumu Zhang
A series of tridentate ferrocene-based amino-phosphine acid (f-Ampha) ligands have been successfully developed. The f-Ampha ligands are extremely air stable and exhibited excellent performance in the Ir-catalyzed asymmetric hydrogenation of ketones (full conversions, up to >99% ee, and 500 000 TON). DFT calculations were performed to elucidate the reaction mechanism and the importance of the -COOH group. Control experiments also revealed that the -COOH group played a key role in this reaction.
January 17, 2017: Organic Letters
Javad Amani, Gary A Molander
Visible light photoredox/nickel dual catalysis has been employed in the cross-coupling of acyl chlorides with potassium alkyltrifluoroborates. This protocol, based on single-electron-mediated alkyl transfer, circumvents the restriction of using reactive alkylmetallic nucleophiles in transition-metal-catalyzed acylation and achieves a mild and efficient method for the synthesis of unsymmetrical alkyl ketones. In this approach, a variety of acyl chlorides have been successfully coupled with structurally diverse potassium alkyltrifluoroborates, generating the corresponding ketones with good yields...
January 17, 2017: Journal of Organic Chemistry
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"