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Teemu Karjalainen, Konsta Pamilo, Aleksi Reito
We describe 2 cases of articulation-related failures resulting in revision surgery after a Motec total wrist arthroplasty: one with an adverse reaction to metal debris and the other with an adverse reaction to polyether ether ketone. In the first patient, blood cobalt and chrome levels were elevated and magnetic resonance imaging showed clear signs of a pseudotumor. The other patient had an extensive release of polyether ether ketone particles into the surrounding synovia due to adverse wear conditions in the cup, leading to the formation of a fluid-filled cyst sac with a black lining and diffuse lymphocyte-dominated inflammation in the synovia...
April 21, 2018: Journal of Hand Surgery
Petra Králová, Michal Maloň, Hiroyuki Koshino, Miroslav Soural
The preparation of 5-methylene-thiohydantoins using solid-phase synthesis is reported in this paper. After sulfonylation of immobilized Ser ( t -Bu)-OH with 4-nitrobenzenesulfonyl chloride followed by alkylation with various bromoketones, the 4-Nos group was removed and the resulting polymer-supported α-acylamino ketones reacted with Fmoc-isothiocyanate. Cleavage of the Fmoc protecting group was followed by the spontaneous cyclative cleavage releasing the 5-methylene-thiohydantoin derivatives from the polymer support...
April 23, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Rolf Breinbauer, Kathrin Heckenbichler, Anna Katharina Schweiger, Lea Alexandra Brandner, Alexandra Binter, Marina Toplak, Peter Macheroux, Karl Gruber
Ene reductases from the Old Yellow Enzyme (OYE) family reduce the carbon-carbon double bond in alpha,beta-unsaturated compounds bearing an electron withdrawing group, e.g. a carbonyl group. This asymmetric reduction has been exploited for biocatalysis. Going beyond its canonical function, we could show that members of this enzyme family can also catalyze the formation of C-C bonds. alpha,beta-Unsaturated aldehydes and ketones containing an additional electrophilic group undergo a reductive cyclization. Mechanistically, the two-electron reduced enzyme cofactor FMN delivers a hydride generating an enolate intermediate, which reacts with the internal electrophile...
April 24, 2018: Angewandte Chemie
Denis Barry, Sarah Ellul, Lindsey Watters, David Lee, Robert Haluska, Robin White
The ketogenic diet, low in carbohydrates and high in fat, was initially designed to reduce seizure onset in epilepsy. More recent evidence has shown its effectiveness in the treatment of movement and psychological disorders, and in general health maintenance. The cellular significance of ketone body metabolism during development and in the adult central nervous system is being revealed; however, the effects of replacing glucose with ketone bodies as the brains primary energy source especially in pregnancy are not fully understood...
April 21, 2018: International Journal of Developmental Neuroscience
Aida I Vientós-Plotts, Ellen N Behrend, Elizabeth G Welles, Dennis J Chew, Philippe R Gaillard, Jessica N Busler, Hollie P Lee
OBJECTIVE To evaluate effects of blood contamination on dipstick results, specific gravity (SG), and urine protein-to-urine creatinine ratio (UPCR) for urine samples from dogs and cats. SAMPLE Urine samples collected from 279 dogs and 120 cats. PROCEDURES Urine pools were made for each species (dogs [n = 60] and cats [30]). Blood was added to an aliquot of a pool, and serial dilutions were prepared with the remaining urine. Color and dipstick variables were recorded, and SG and UPCR were measured. For cats, 1 set of pools was used; for dogs, 2 sets were used...
May 2018: American Journal of Veterinary Research
Rong Wang, Zilin Chen
A poly(vinylphenylboronic acid-ethylene glycol dimethacrylate) monolithic material incorporated with graphene oxide was synthesized inside a poly(ether ether ketone) tube. This tube with boronate affinity monolith was coupled with a high-performance liquid chromatography system through a six-port valve, and constructed an online solid-phase microextraction with high-performance liquid chromatography system. The performance of this solid phase microextraction with high-performance liquid chromatography system was demonstrated by standard glycoprotein in aqueous samples, namely, horseradish peroxidase...
April 23, 2018: Journal of Separation Science
Aman Bhakti Pulungan, Erlin Juwita, Antonius H Pudjiadi, Siti Rahmayanti, Ireska Tsaniya
BACKGROUND: diabetic ketoacidosis (DKA) is a potentially lethal complication of diabetes mellitus (DM). There is no study in Indonesia that compares the much-preferred capillary beta hydroxybutirate (β-OHB) measurement to urine acetoacetate in monitoring therapeutic response of DKA in adolescents. METHODS: a prospective study of 37 adolescents and children with DKA in Cipto Mangunkusumo Hospital was done between June 2006 and March 2011. The patients were followed until the time of DKA resolution...
January 2018: Acta Medica Indonesiana
L Y Wen, Y S Zhang, X Zhou, G Li, C Y Hu, Y Li, L J Jin
This study aimed to investigate the effect of branched chain amino acids (BCCAs) on perioperative temperature, glucose and fat metabolism in patients with gastrointestinal tumors. Fifty-six patients undergoing gastrointestinal tumor surgery were included in the study and randomly divided into two groups of 28 patients each: an experimental and a control group. During surgery, the experimental group received 5.64mL·Kg-1·h-1(4KJ·Kg-1·h-1) of BCCAs intravenously, through an infusion pump, and the control group received an equal volume of NaCl 0...
March 2018: Journal of Biological Regulators and Homeostatic Agents
Jinping Gu, Chenyang Ji, Siqing Yue, Dan Shu, Feng Su, Yinjun Zhang, Yuanyuan Xie, Yi Zhang, Weiping Liu, Meirong Zhao
More than 30% of the registered pesticides are chiral with one or more chiral centers and exist as two or more enantiomers. The frequency of chiral chemicals and their environmental safety has been considered in their risk assessment in recent decades. Despite the fact that metabolic disturbance is an important sensitive molecular initiating event of toxicology effects, the potential mechanisms of how chiral compounds affect metabolism phenotypes in organisms remain unclear. As a typical chiral pesticide, metalaxyl is an acylalanine fungicide with systemic function...
April 23, 2018: Environmental Science & Technology
Chao Che, Zhaosheng Qian, Mingchang Wu, Ying Zhao, Gangguo Zhu
A novel silver-catalyzed ring-opening acylation of cyclopropanols and cyclobutanols is described. The reaction proceeds under mild and neutral conditions and provides a facile access to nonsymmetric 1,4- and 1,5-diketones in promising yields with broad substrate scope. Mechanistic studies including DFT calculations suggest the involvement of an uncommon water-assisted 1,2-HAT process, which is strongly exothermic and thus promotes addition of carbon radicals to aldehydes. In contrast to traditional reductive radical addition protocols, this work represents the first example on the intermolecular oxidative radical addition to aldehydes, thus offering a novel strategy for the direct synthesis of acyclic ketones from readily accessible aldehydes...
April 23, 2018: Journal of Organic Chemistry
Mohd Waheed, Naseem Ahmed, Meshari A Alsharif, Mohammed Issa Alahmdi, Sayeed Mukhtar
A facile synthesis of 1,5-diketones from 3-acetyl-4-hydroxycoumarin, aldehydes and cyclic-ketones via a one-pot aldol condensation and subsequent Michael addition reaction in the presence of a single catalyst of l-proline under mild reaction conditions has been developed. Novel 1,5-diketones were further cyclized to unexpected 3,4-dihydropyridines rather than generally formed pyridine analogues with ammonium acetate in acetic acid. One pot, high yields (72-92%) for novel 1,5-diketones and (70-90%) for the 3,4-dihydropyridine adducts, easy work-up and purification of products are the key advantages of this method...
April 23, 2018: Organic & Biomolecular Chemistry
Timothy B Boit, Nicholas A Weires, Junyong Kim, Neil K Garg
We report the Ni-catalyzed Suzuki-Miyaura coupling of aliphatic amide derivatives. Prior studies have shown that aliphatic amide derivatives can undergo Ni-catalyzed carbon-heteroatom bond formation but that Ni-mediated C-C bond formation using aliphatic amide derivatives has remained difficult. The coupling disclosed herein is tolerant of considerable variation with respect to both the amide-based substrate and the boronate coupling partner and proceeds in the presence of heterocycles and epimerizable stereocenters...
February 2, 2018: ACS Catalysis
Mohammad Paknahad, Jannat Singh Bachhal, Mina Hoorfar
This paper presents a cost-effective and reliable diffusion-based humidity removal membrane for microfluidic-based gas analyzers. The developed humidity control device reduces the relative humidity of a gas chamber and also stabilizes the humidity using inexpensive inorganic salts. A 3D-printed microfluidic gas sensor is used to test four different volatile organic compounds (VOCs) including three alcohols and one ketone in different relative humidity levels ranging from 15% to 80%. To study the effects of humidity on different features of the transient response of the sensor, two different feature extraction methods are used...
August 27, 2018: Analytica Chimica Acta
Wei Zhou, Chenlu Wang, Xuemei Wang, Zilin Chen
Development of stir bar sorptive extraction (SBSE) device with high stability and extraction efficiency is critical and challenging by date. In this work, etched poly(ether ether ketone) (PEEK) tube with high mechanical strength and large specific surface area was used as jacket for SBSE device. By etching with concentrated sulfuric acid, the smooth outer surface of PEEK become porous with plenty of micro holes, which was beneficial for coating of sorbents and significantly improved the extraction performance...
April 12, 2018: Journal of Chromatography. A
Jin Qian, Kun Li, Peifang Wang, Chao Wang, Jingjing Liu, Xin Tian, Bianhe Lu, Wenyi Guan
Engineered nano-TiO2 (Enano-TiO2 ) have inevitably discharged into aquatic sediments that resulted from their widespread use. The physicochemical characteristics of sediments might be changed because of remarkable properties of Enano-TiO2 and affected by the aging of sediments, thereby altering the environmental behavior and bioavailability of other pollutants such as perfluorooctane sulfonate (PFOS) in sediments. Here, adsorption behavior and mechanism of PFOS on aging aquatic sediments spiked with Enano-TiO2 at a weight ratio of 5...
April 20, 2018: Environmental Science and Pollution Research International
Kaitlyn Dahlgren, Kelly J Gibas
Alzheimer's disease (AD) deaths have increased by 89% since 2000. This alarming trajectory of neurological disease highlights the failure of current best practice. Deteriorating brain fuel supply is the nemesis of intact neurological health. Cerebral hypo-metabolism associated with AD occurs years before onset. Both the ketogenic diet and calorie restriction (fasting) lead to a compensatory rise in ketones to improve energy deficits in the brain derived from cerebral insulin resistance. Two forms of ketone bodies, β-hydroxybutyrate and acetoacetate, fuel the brain during starvation, fasting and strenuous exercise...
April 11, 2018: Diabetes & Metabolic Syndrome
Byeol-Nim Lee, Tae Yang Son, Chi Hoon Park, Tae Hyun Kim, Sang Yong Nam
In this study, various poly(ether ether ketone) were synthesized using three different monomers and the imidazolium group was introduced into synthesized poly(ether ether ketone)s by using substitution reaction. Synthesized polymers were used to prepare anion exchange membranes and to evaluate its properties. Thermal, chemical and structural properties were carried out using thermogravimetric analysis, nuclear magnetic resonance. The anion exchange membranes with different imidazolium moieties were characterized by several different analytical techniques such as water up take, ion exchange capacity, hydroxide conductivity for checking the possibility to apply the anion exchange membrane fuel cell...
September 1, 2018: Journal of Nanoscience and Nanotechnology
Young-Min Kim, Gwang Hoon Rhee, Chang Hyun Ko, Ki Hoon Kim, Kyeong Youl Jung, Ji Man Kim, Young-Kwon Park
The thermal and catalytic pyrolysis of Pinus densiflora (P. densiflora) were performed to test the catalytic cracking efficiency of two mesoporous Al2O3 catalysts with different surface areas. Thermogravimetric analysis (TGA) of P. densiflora showed that the differential TG (DTG) peak heights obtained from catalytic pyrolysis were smaller than those of non-catalytic pyrolysis due to the conversion of the reaction intermediates to coke. Pyrolyzer-gas chromatography/mass spectrometry analysis/flame ionization detection (Py-GC/MS/FID) suggested that using the Al2O3 catalysts, the yields of phenols and levoglucosan decreased with a concomitant increase in the yields of aldehydes, alcohol, ketones, and furans...
September 1, 2018: Journal of Nanoscience and Nanotechnology
Mabrouk Attia Abd Eldaim, Fatma Mohamed Ibrahim, Sahar H Orabi, Azza Hassan Morsi, Hesham Saad ElSabbagh
In this study the possible mechanisms through which L-carnitine ameliorates the adverse effects of high fat diet (HFD) induced obesity on rats was evaluated. 56 Wister albino rats were randomly assigned into seven groups. Control rats fed basal diet. 2nd group fed basal diet and injected with L-carnitine 200 mg/kg i.p. 3rd group fed HFD. 4th group fed HFD and injected with L-Carnitine 200 mg/kg i.p for 8 weeks. 5th group fed HFD for 10 weeks. 6th group fed HFD for 10 weeks and injected with L-Carnitine 200 mg/kg i...
April 20, 2018: Biochemistry and Cell Biology, Biochimie et Biologie Cellulaire
Xinxin Zheng, Rui Guo, Guozhu Zhang, Dayong Zhang
We report a rhodium-catalyzed asymmetric formal intermolecular [4 + 2] cycloaddition reaction of 2-alkylenecyclobutanols with α,β-unsaturated cyclic ketones leading to synthetically useful trans -bicyclic molecules. Three consecutive stereogenic centers are formed in a highly enantio- and diastereoselective manner. Stepwise C-C bond cleavage and annulation are likely involved in the reaction pathway. Here, iPr-Duphos is the viable chiral ligand that promotes excellent enantio-control.
February 21, 2018: Chemical Science
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