keyword
MENU ▼
Read by QxMD icon Read
search

S-4

keyword
https://www.readbyqxmd.com/read/28527146/real-time-elastography-rte-a-valuable-sonography-based-non-invasive-method-for-the-assessment-of-liver-fibrosis-in-chronic-hepatitis-b
#1
Tianyi Wang, Cuiping Shao, Guosheng Zhang, Youqing Xu
PURPOSE: To investigate the diagnostic usefulness of real-time elastography (RTE) for liver fibrosis in chronic hepatitis B (CHB). METHODS: 89 CHB patients were enrolled in the cross-sectional study. Ultrasound-guided percutaneous liver biopsies, RTE, and blood testing were performed in all patients. Areas under receiver operating characteristic curves (AUROC) were used to examine the diagnostic performance of liver fibrosis index (LFI) for the assessment of liver fibrosis...
May 19, 2017: Abdominal Radiology
https://www.readbyqxmd.com/read/28501431/lipase-catalyzed-kinetic-resolution-as-key-step-in-the-synthesis-of-enantiomerically-pure-%C3%AF-ligands-with-2-benzopyran-structure
#2
Inga Knappmann, Kirstin Lehmkuhl, Jens Köhler, Dirk Schepmann, Martin Giera, Franz Bracher, Bernhard Wünsch
In order to obtain enantiomerically pure σ1 receptor ligands with a 2-benzopyran scaffold an Oxa-Pictet-Spengler reaction with the enantiomerically pure 2-phenylethanol derivatives (R)-4 and (S)-4 was envisaged. The kinetic resolution of racemic alcohol (±)-4 using Amano Lipase PS-C II and isopropenyl acetate in tert-butyl methyl ether led to the (R)-configured alcohol (R)-4 in 42% yield with an enantiomeric excess of 99.6%. The (S)-configured alcohol (S)-4 was obtained by Amano Lipase PS-C II catalyzed hydrolysis of enantiomerically enriched acetate (S)-5 (76...
April 30, 2017: Bioorganic & Medicinal Chemistry
https://www.readbyqxmd.com/read/28498623/interplay-of-electronic-cooperativity-and-exchange-coupling-in-regulating-the-reactivity-of-diiron-iv-oxo-complexes-towards-c-h-and-o-h-bond-activation
#3
Gopalan Rajaraman, Azaj Ansari, Asmita Singha, Mursaleem Ansari
Activation of inert C-H bonds such as those of methane are extremely challenging for chemists but in the nature, soluble methane monooxygenase enzyme readily oxidize methane to methanol using a diiron(IV) species. This has prompted chemists to look for similar model systems. Recently a (μ-oxo)bis(μ-carboxamido)diiron(IV) ([Fe(IV)2O(L)2]2+ L= N,N-bis-(3',5'-dimethyl-4'-methoxypyridyl-2'-methyl)-N'-acetyl- 1,2-diaminoethane) complex has been generated via bulk electrolysis and this species activates an inert C-H bond almost 1000 times faster compared to mononuclear Fe(IV)=O species and at the same time selectively activates O-H bonds of alcohols...
May 12, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28483535/a-battery-of-assays-as-an-integrated-approach-to-evaluate-fungal-and-mycotoxin-inhibition-properties-and-cytotoxic-genotoxic-side-effects-for-the-prioritization-in-the-screening-of-thiosemicarbazone-derivatives
#4
Claudia Zani, Franco Bisceglie, Francesco Maria Restivo, Donatella Feretti, Marianna Pioli, Francesca Degola, Serena Montalbano, Serena Galati, Giorgio Pelosi, Gaia V C Viola, Mauro Carcelli, Dominga Rogolino, Elisabetta Ceretti, Annamaria Buschini
Aflatoxins represent a serious problem for a food economy based on cereal cultivations used to fodder animal and for human nutrition. The aims of our work are two-fold: first, to perform an evaluation of the activity of newly synthesized thiosemicarbazone compounds as antifungal and anti-mycotoxin agents and, second, to conduct studies on the toxic and genotoxic hazard potentials with a battery of tests with different endpoints. In this paper we report an initial study on two molecules: S-4-isopropenylcyclohexen-1-carbaldehydethiosemicarbazone and its metal complex, bis(S-4-isopropenylcyclohexen-1-carbaldehydethiosemicarbazonato)nickel (II)...
May 5, 2017: Food and Chemical Toxicology
https://www.readbyqxmd.com/read/28482368/validity-of-postexercise-measurements-to-estimate-peak-vo2-in-200-m-and-400-m-maximal-swims
#5
Ferran A Rodríguez, Diego Chaverri, Xavier Iglesias, Thorsten Schuller, Uwe Hoffmann
To assess the validity of postexercise measurements to estimate oxygen uptake (V˙O2) during swimming, we compared V˙O2 measured directly during an all-out 200-m swim with measurements estimated during 200-m and 400-m maximal tests using several methods, including a recent heart rate (HR)/V˙O2 modelling procedure. 25 elite swimmers performed a 200-m maximal swim where V˙O2 was measured using a swimming snorkel connected to a gas analyzer. The criterion variable was V˙O2 in the last 20 s of effort, which was compared with the following V˙O2peak estimates: 1) first 20-s average; 2) linear backward extrapolation (BE) of the first 20 and 30 s, 3×20-s, 4×20-s, and 3×20-s or 4×20-s averages; 3) semilogarithmic BE at the same intervals; and 4) predicted V˙O2peak using mathematical modelling of 0-20 s and 5-20 s during recovery...
May 8, 2017: International Journal of Sports Medicine
https://www.readbyqxmd.com/read/28479417/gait-speed-and-survival-in-patients-with-brain-metastases
#6
Caleb Dulaney, Andrew McDonald, Audrey S Wallace, John Fiveash
CONTEXT: Accurate estimation of life expectancy in patients with brain metastases is critical for counselling and choosing appropriate therapy. Performance status is the single greatest determinant of overall survival in this population. However, current measures of performance status are subjective and often based on brief clinical encounters. Gait speed is an objective, reliable predictor of overall health and survival. OBJECTIVE: The purpose of this study was to evaluate the relationship between gait speed and survival in patients with brain metastases...
May 4, 2017: Journal of Pain and Symptom Management
https://www.readbyqxmd.com/read/28457879/the-role-of-system-xc-in-methamphetamine-induced-dopaminergic-neurotoxicity-in-mice
#7
Duy-Khanh Dang, Eun-Joo Shin, Hai-Quyen Tran, Dae-Joong Kim, Ji Hoon Jeong, Choon-Gon Jang, Seung-Yeol Nah, Hideyo Sato, Toshitaka Nabeshima, Yukio Yoneda, Hyoung-Chun Kim
The cystine/glutamate antiporter (system Xc(-), Sxc) transports cystine into cell in exchange for glutamate. Since xCT is a specific subunit of Sxc, we employed xCT knockout mice and investigated whether this antiporter affected methamphetamine (MA)-induced dopaminergic neurotoxicity. MA treatment significantly increased striatal oxidative burdens in wild type mice. xCT inhibitor [i.e., S-4-carboxy-phenylglycine (CPG), sulfasalazine] or an xCT knockout significantly protected against these oxidative burdens...
April 27, 2017: Neurochemistry International
https://www.readbyqxmd.com/read/28453941/probing-molecular-interactions-between-human-carbonic-anhydrases-hcas-and-a-novel-class-of-benzenesulfonamides
#8
Elvira Bruno, Maria Rosa Buemi, Anna Di Fiore, Laura De Luca, Stefania Ferro, Andrea Angeli, Roberto Cirilli, Daniele Sadutto, Vincenzo Alterio, Simona Maria Monti, Claudiu T Supuran, Giuseppina De Simone, Rosaria Gitto
On the basis of X-ray crystallographic studies of the complex of hCA II with 4-(3,4-dihydro-1H-isoquinoline-2-carbonyl)benzenesulfonamide (3) (PDB code 4Z1J ), a novel series of 4-(1-aryl-3,4-dihydro-1H-isoquinolin-2-carbonyl)benzenesulfonamides (23-33) was designed. Specifically, our idea was to improve the selectivity toward druggable isoforms through the introduction of additional hydrophobic/hydrophilic functionalities. Among the synthesized and tested compounds, the (R,S)-4-(6,7-dihydroxy-1-phenyl-3,4-tetrahydroisoquinoline-1H-2-carbonyl)benzenesulfonamide (30) exhibited a remarkable inhibition for the brain-expressed hCA VII (Ki = 0...
May 9, 2017: Journal of Medicinal Chemistry
https://www.readbyqxmd.com/read/28446460/inhibition-of-cholinergic-neurotransmission-by-%C3%AE-3-adrenoceptors-depends-on-adenosine-release-and-a1-receptors-activation-in-human-and-rat-urinary-bladders
#9
Isabel Silva, Ana Filipa Costa, Sílvia Moreira, Fátima Ferreirinha, Maria Teresa Magalhães-Cardoso, Isabel Calejo, Miguel Silva-Ramos, Paulo Correia-de-Sá
The direct detrusor relaxant effect of β3-adrenoceptor agonists as a primary mechanism to improve overactive bladder symptoms has been questioned. Among other targets, activation of β3-adrenoceptors down-modulate nerve-evoked acetylcholine (ACh) release, but there is insufficient evidence for the presence of these receptors on bladder cholinergic nerve terminals. Our hypothesis is that adenosine formed from the catabolism of cyclic AMP in the detrusor may act as a retrograde messenger via prejunctional A1 receptors to explain inhibition of cholinergic activity by β3-adrenoceptors...
April 26, 2017: American Journal of Physiology. Renal Physiology
https://www.readbyqxmd.com/read/28435717/a-cinnamaldehyde-schiff-base-of-s-4-methyl-benz-yl-di-thio-carbazate-crystal-structure-hirshfeld-surface-analysis-and-computational-study
#10
Enis Nadia Md Yusof, Mohamed I M Tahir, Thahira B S A Ravoof, Sang Loon Tan, Edward R T Tiekink
The title di-thio-carbazate ester (I), C18H18N2S2 [systematic name: (E)-4-methyl-benzyl 2-[(E)-3-phenyl-allyl-idene]hydrazinecarbodi-thio-ate, comprises an almost planar central CN2S2 residue [r.m.s. deviation = 0.0131 Å]. The methyl-ene(tolyl-4) group forms a dihedral angle of 72.25 (4)° with the best plane through the remaining non-hydrogen atoms [r.m.s. deviation = 0.0586 Å] so the mol-ecule approximates mirror symmetry with the 4-tolyl group bis-ected by the plane. The configuration about both double bonds in the N-N=C-C=C chain is E; the chain has an all trans conformation...
April 1, 2017: Acta Crystallographica. Section E, Crystallographic Communications
https://www.readbyqxmd.com/read/28427921/enhancement-of-ethyl-s-4-chloro-3-hydroxybutanoate-production-at-high-substrate-concentration-by-in-situ-resin-adsorption
#11
Li-Feng Chen, Hai-Yang Fan, Yi-Ping Zhang, Wei Wei, Jin-Ping Lin, Dong-Zhi Wei, Hua-Lei Wang
Asymmetric reduction of ethyl 4-chloro-3-oxobutyrate (COBE) by carbonyl reductases presents an efficient way to produce Ethyl (S)-4-chloro-3-hydroxybutanoate ((S)-CHBE), an important chiral intermediate for the synthesis of hydroxymethylglutaryl-CoA reductase inhibitors such as Lipitor(®). In this study, an NADPH-dependent carbonyl reductase (SrCR) from Synechocystis sp. was characterized to demonstrate a broad substrate spectrum, and the highest activity (53.1U/mg protein) with COBE. To regenerate the cofactor NADPH, Bacillus subtilis glucose dehydrogenase was successfully coexpressed with SrCR...
April 17, 2017: Journal of Biotechnology
https://www.readbyqxmd.com/read/28419755/a-diagnostic-algorithm-for-assessment-of-liver-fibrosis-by-liver-stiffness-measurement-in-patients-with-chronic-hepatitis-b
#12
Yi-Jing Cai, Jia-Jia Dong, Xiao-Dong Wang, Si-Si Huang, Rui-Cong Chen, Yi Chen, Yu-Qun Wang, Mei Song, Yong-Ping Chen, Zhuo Li, Meng-Tao Zhou, Ke-Qing Shi
Steatosis could affect liver stiffness measurement in patients with nonalcoholic fatty liver disease and chronic hepatitis C. In the current study, we aimed to investigate the impact of steatosis on liver stiffness in chronic hepatitis B virus infected patients and develop a diagnostic algorithm for prediction of liver fibrosis by liver stiffness based on the controlled attenuation parameter. A total of 488 HBV infected patients who underwent clinical examination, FibroScan and liver biopsy were prospectively enrolled...
April 17, 2017: Journal of Viral Hepatitis
https://www.readbyqxmd.com/read/28412676/investigation-of-sub-health-status-of-neonates-in-heping-street-region-beijing-and-analysis-on-related-risk-factors
#13
Chen Jie, Shi Mai, Li Qiuju, Ye Fang, Liu Fang, Fan Qinying, Zhang Yong, Wang Lin
To investigate sub-health status of neonates in Heping Street Region and related risk factors. Then, 7436 maternal women admitted to hospital in Heping Street Region, Beijing were enrolled from October 2013 to September 2015, including 293 women, who gave birth to sub-health neonates. Questionnaire survey was conducted to collect maternal age, education degree, experiences and income, occupation, life habit, condition in pregnancy, condition in perinatal period, adverse reaction in pregnancy, etc. Finally, 281 effective questionnaires were regained with effective regain rate of 95...
November 2016: Pakistan Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/28407352/copper-catalyzed-aminothiolation-of-1-3-dienes-via-a-dihydrothiazine-intermediate
#14
Christopher E Sleet, Uttam K Tambar
Heteroatom-containing organic molecules are of particular interest to medicinal chemists and materials scientists. A strategy to reach these architectures via direct difunctionalization of abundant 1,3-dienes is especially attractive. Herein, we describe the development of a regio- and diastereoselective 1,4-aminothiolation of 1,3-dienes with a sulfur diimide reagent, a copper catalyst, and alkyl Grignard reagents. This unique protocol provides remote nitrogen and sulfur functionalities with high levels of stereocontrol...
May 8, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28395308/evaluation-of-a-training-program-to-reduce-stressful-trunk-postures-in-the-nursing-professions-a-pilot-study
#15
Agnessa Kozak, Sonja Freitag, Albert Nienhaus
Objectives: The aim of this pilot study was to evaluate metrologically the effectiveness of a training program on the reduction of stressful trunk postures in geriatric nursing professions. Methods: A training program, consisting of instruction on body postures in nursing, practical ergonomic work methods at the bedside or in the bathroom, reorganization of work equipment, and physical exercises, was conducted in 12 wards of 6 nursing homes in Germany. The Computer-Assisted Recording and Long-Term Analysis of Musculoskeletal Loads (CUELA) measurement system was used to evaluate all movements and trunk postures adopted during work before and 6 months after the training program...
January 1, 2017: Annals of Work Exposures and Health
https://www.readbyqxmd.com/read/28392421/phenylalanine-ammonia-lyase-from-arabidopsis-thaliana-atpal2-a-potent-enzyme-for-the-synthesis-of-non-canonical-aromatic-alpha-amino-acids-part-i-comparative-characterization-to-the-enzymes-from-petroselinum-crispum-pcpal1-and-rhodosporidium-toruloides-rtpal
#16
Alana Dreßen, Thomas Hilberath, Ursula Mackfeld, Arne Billmeier, Jens Rudat, Martina Pohl
Phenylalanine ammonia lyase (PAL) from Arabidopsis thaliana (AtPAL2) was comparatively characterized to the well-studied enzyme from parsley (PcPAL1) and Rhodosporidium toruloides (RtPAL) with respect to kinetic parameters for the deamination and the amination reaction, pH- and temperature optima and the substrate range of the amination reaction. Whereas both plant enzymes are specific for phenylalanine, the bifunctional enzyme from Rhodosporidium toruloides shows KM-values for L-Phe and L-Tyr in the same order of magnitude and, compared to both plant enzymes, a 10-15-fold higher activity...
April 6, 2017: Journal of Biotechnology
https://www.readbyqxmd.com/read/28389544/engineering-streptomyces-coelicolor-carbonyl-reductase-for-efficient-synthesis-of-atorvastatin-precursor
#17
Min Li, Zhi-Jun Zhang, Xu-Dong Kong, Hui-Lei Yu, Jiahai Zhou, Jian-He Xu
ScCR1 has been shown to be a promising biocatalyst for the synthesis of an atorvastatin precursor, ethyl (S)-4-chloro-3-hydroxybutyrate. However, limitations of ScCR1 observed for practical application include the low activity and poor stability. In this work, protein engineering was employed to improve the catalytic efficiency and stability of ScCR1. At first, the crystal structure of ScCR1 complexed with NADH and co-substrate 2-propanol was solved, and the specific activity of ScCR1 was increased from 38...
April 7, 2017: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/28387663/quantitative-parameters-of-contrast-enhanced-ultrasound-in-breast-invasive-ductal-carcinoma-the-correlation-with-pathological-prognostic-factors
#18
Chen-Li Ji, Xiao-Long Li, Ya-Ping He, Dan-Dan Li, Xin-Gang Gu, Hui-Xiong Xu
PURPOSE: To investigate the correlation between quantitative parameters on contrast-enhanced ultrasound (CEUS) and pathological prognostic factors in patients with breast invasive ductal carcinomas (IDCs). MATERIALS AND METHODS: 102 patients with pathologically proven IDCs were retrospectively enrolled and all were preoperatively evaluated by CEUS. Quantitative analysis was conducted using the SonoLiver® software. On the parametric imaging, the data of rise time (RT), time to peak (TTP), mean transit time (mTT) and maximum intensity (IMAX) were recorded...
April 4, 2017: Clinical Hemorheology and Microcirculation
https://www.readbyqxmd.com/read/28375005/expanding-the-chemical-repertoire-of-the-endophyte-streptomyces-albospinus-rle7-reveals-amphotericin-b-as-an-inducer-of-a-fungal-phenotype
#19
Fernanda Oliveira Chagas, Andrés Mauricio Caraballo-Rodríguez, Pieter C Dorrestein, Mônica Tallarico Pupo
During an investigation of the chemistry of the endophytic actinobacterium Streptomyces albospinus RLe7, which was isolated from the roots of the Brazilian medicinal plant Lychnophora ericoides, three new natural products, (2R*,4S*)-2-((1'S*)-hydroxy-4'-methylpentyl)-4-(hydroxymethyl)butanolide (1), (3R*,4S*,5R*,6S*)-tetrahydro-4-hydroxy-3,5,6-trimethyl-2-pyranone (2), and 1-O-(phenylacetyl)glycerol (3), together with known secondary metabolites (S)-4-benzyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (4), (S)-4-isobutyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (5), and the diketopiperazines cyclo(l-Tyr-l-Pro) (6) and cyclo(l-Val-l-Pro) (7), were isolated...
April 4, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/28374860/640-gbit-s-fast-physical-random-number-generation-using-a-broadband-chaotic-semiconductor-laser
#20
Limeng Zhang, Biwei Pan, Guangcan Chen, Lu Guo, Dan Lu, Lingjuan Zhao, Wei Wang
An ultra-fast physical random number generator is demonstrated utilizing a photonic integrated device based broadband chaotic source with a simple post data processing method. The compact chaotic source is implemented by using a monolithic integrated dual-mode amplified feedback laser (AFL) with self-injection, where a robust chaotic signal with RF frequency coverage of above 50 GHz and flatness of ±3.6 dB is generated. By using 4-least significant bits (LSBs) retaining from the 8-bit digitization of the chaotic waveform, random sequences with a bit-rate up to 640 Gbit/s (160 GS/s × 4 bits) are realized...
April 4, 2017: Scientific Reports
keyword
keyword
81439
1
2
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"