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https://www.readbyqxmd.com/read/28738612/sorption-luminescence-method-for-determination-of-terbium-using-transcarpathian-clinoptilolite
#1
V O Vasylechko, G V Gryshchouk, V P Zakordonskiy, L O Vasylechko, M Schmidt, I M Leshchack, Ya M Kalychak, S R Bagday
Sorption-luminescent method for terbium determination based on natural Transcarpathian clinoptilolite without using of complex synthetic organic compounds and toxic solvents was proposed. Optimal luminophore preparation conditions are sorption of Tb(III) on zeolite in the borate buffer solution with pH 8.25 and further calcination of clinoptilolite-Tb(III) samples at 500°C. For luminescence excitation the rays with wavelength of λ = 220nm of were used. Luminescence intensity at λ = 545nm was selected as analytical parameter for a quantitative terbium determination...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738603/vortex-assisted-liquid-liquid-liquid-microextraction-followed-by-high-performance-liquid-chromatography-for-the-simultaneous-determination-of-fourteen-phenolic-acids-in-honey-iced-tea-and-canned-coffee-drinks
#2
Marwan Shalash, Ahmad Makahleh, Salizawati Muhamad Salhimi, Bahruddin Saad
A vortex-assisted liquid-liquid-liquid microextraction method followed by high performance liquid chromatography-diode array detection for the determination of fourteen phenolic acids (cinnamic, m-coumaric, chlorogenic, syringic, ferulic, o-coumaric, p-coumaric, vanillic, p-hydroxybenzoic, caffeic, 2, 4-dihydroxybenzoic, sinapic, gentisic and gallic acids) in honey, iced tea and canned coffee drink samples has been developed. The separation was achieved using a Poroshell 120-EC-C18 column under a gradient elution at a flow rate of 0...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738569/optoacoustic-determination-of-analytical-parameters-and-physicochemical-constants-in-highly-concentrated-solutions-of-chromophores
#3
Kristina V Lobko, Mikhail A Shishkin, Tatyana A Filimonova, Dmitry S Volkov, Ivan M Pelivanov, Mikhail A Proskurnin
Determination of chromophores of various classes-rosaniline (fuchsine), cyanidin-3-O-glucoside, tris(1,10-phenanthroline) iron(II), and phenol red - in their concentrated solutions near their solubility limits is performed with the optoacoustic technique for optically dense solutions; light-absorption coefficients of samples range from 0.5 to 500cm(-1). The assessment of these substances in organo-aqueous and organic solvents is possible up to ca. 0.1molL(-1). Characteristic stability and rate constants of the chelation of iron(II) with 1,10-phenanthroline are determined...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738552/nutrients-removal-and-bacterial-community-structure-for-low-c-n-municipal-wastewater-using-a-modified-anaerobic-anoxic-oxic-ma2-o-process-in-north-china
#4
Shihua Zhang, Zhijia Huang, Shujian Lu, Jun Zheng, Xinxi Zhang
A modified anaerobic/anoxic/oxic (mA2/O) process based on utilizing the internal carbon source and adding polypropylene carriers was operated for 90d to investigate the nutrients removal performance and bacterial community. This system exhibited a stable and efficient performance, particularly, in removing the NH4(+)-N and total phosphorus. The results of high-throughput sequencing showed that the 13 dominant genera containing Pseudomonas, Comamonas, Arcobacter, Nitrobacteria, Nitrosospira, Nitrosomonas, Bacteroides, Flavobacterium, Rhizobium, Acinetobacter, Zoogloea, Rhodocyclus and Moraxella were shared by five zones, inferring that they were the essential players in treating low C/N (below 5...
July 12, 2017: Bioresource Technology
https://www.readbyqxmd.com/read/28738549/chemical-and-structural-characterization-of-char-development-during-lignocellulosic-biomass-pyrolysis
#5
Lihle D Mafu, Hein W J P Neomagus, Raymond C Everson, Christien A Strydom, Marion Carrier, Gregory N Okolo, John R Bunt
The chemical and structural changes of three lignocellulosic biomass samples during pyrolysis were investigated using both conventional and advanced characterization techniques. The use of ATR-FTIR as a characterization tool is extended by the proposal of a method to determine aromaticity, the calculation of both CH2/CH3 ratio and the degree of aromatic ring condensation ((R/C)u). With increasing temperature, the H/C and O/C ratios, XA and CH2/CH3 ratio decreased, while (R/C)u and aromaticity increased. The micropore network developed with increasing temperature, until the coalescence of pores at 1100°C, which can be linked to increasing carbon densification, extent of aromatization and/or graphitization of the biomass chars...
July 6, 2017: Bioresource Technology
https://www.readbyqxmd.com/read/28738538/diosmin-improved-cognitive-deficit-and-amplified-brain-electrical-activity-in-the-rat-model-of-traumatic-brain-injury
#6
Mohammad Ali Mirshekar, Hamed Fanaei, Fereshteh Keikhaei, Fatemeh Sargolzaee Javan
OBJECTIVE: Traumatic brain injury (TBI) is one of the main causes of intellectual and cognitive disabilities in humans. Clinically, it is essential to limit the progress of cognitive impairment after TBI. It is reported that diosmin has a neuroprotective effect that can limit the progress of the impairment. The aim of this study was to evaluate the effects of diosmin on neurological score, memory, tumor necrosis factor-α (TNF-α) level and long-term potentiation in hippocampal dentate gyrus after the injury...
July 20, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28738491/-establishment-of-a-model-of-hydrogen-peroxide-induced-injury-in-pulmonary-artery-endothelium-cells-and-relevant-mechanisms-of-oxidative-stress
#7
J Ye, Y Y He, Y Yan, J H Zhao, T Y Lian, X J Wang, Y Yan, S J Zhang, S H Yang, Z C Jing
Objective: To establish a hydrogen peroxide (H(2)O(2)) induced injury model of pulmonary artery endothelial cells (PAECs) and explore the molecular mechanisms of oxidative stress on the structure and function of PAECs in this model. Methods: Human PAECs were treated with H(2)O(2) at different concentrations (25, 50, 100, 200, 400, 800, 1 600, 3 200, 6 400 μmol/L) for 4 and 24 h, respectively. The PAECs survival curve was obtained according to the cell viability measured by CCK-8 assay. The cell apoptosis of PAECs was detected by flow cytometry...
July 24, 2017: Zhonghua Xin Xue Guan Bing za Zhi
https://www.readbyqxmd.com/read/28738440/issr-derived-species-specific-scar-marker-for-rapid-and-accurate-authentication-of-ocimum-tenuiflorum-l
#8
Amit Kumar, Vereena Rodrigues, Priyanka Mishra, Kuppusamy Baskaran, Ashutosh K Shukla, Ajit K Shasany, Velusamy Sundaresan
Ocimum tenuiflorum has been widely used in traditional medicine and has high medicinal value. High volume trade of this potential medicinal plant species led to unscrupulous adulteration of both crude drugs as well as formulations. Morphology-based authentication is difficult in cases of incomplete or damaged samples and in dried herbal materials. In such cases, PCR-based molecular methods may aid in accurate identification. The present study aimed at developing species-specific DNA marker(s) for the authentication of O...
July 24, 2017: Planta Medica
https://www.readbyqxmd.com/read/28738409/elements-of-eoarchean-life-trapped-in-mineral-inclusions
#9
T Hassenkam, M P Andersson, K N Dalby, D M A Mackenzie, M T Rosing
Metasedimentary rocks from Isua, West Greenland (over 3,700 million years old) contain (13)C-depleted carbonaceous compounds, with isotopic ratios that are compatible with a biogenic origin. Metamorphic garnet crystals in these rocks contain trails of carbonaceous inclusions that are contiguous with carbon-rich sedimentary beds in the host rock, where carbon is fully graphitized. Previous studies have not been able to document other elements of life (mainly hydrogen, oxygen, nitrogen and phosphorus) structurally bound to this carbonaceous material...
July 24, 2017: Nature
https://www.readbyqxmd.com/read/28738308/antiproliferative-and-pro-apoptotic-activities-of-2-and-4-aminochalcones-against-tumor-canine-cells
#10
Mariana B Santos, Vitor C Pinhanelli, Mayara A R Garcia, Gabriel Silva, Seung J Baek, Suzelei C França, Ana L Fachin, Mozart Marins, Luis O Regasini
In the present study, a series of 2'- and 4'-aminochalcones were synthesized and their antiproliferative activity against a canine malignant histiocytic cell line (DH82) was evaluated. Particularly aminochalcones with a hydrophobic substituent on ring B proved to be potent antiproliferative agents. Among these compounds, aminochalcones 3, 4 and 11 inhibited the growth of DH82 cells, with IC50 values of 34.4, 31.4 and 38.2 μM, respectively, and were three times more potent than etoposide (IC50 = 95.5 μM)...
June 27, 2017: European Journal of Medicinal Chemistry
https://www.readbyqxmd.com/read/28738267/gram-scale-synthesis-of-a-type-2-and-b-type-2-blood-group-tetrasaccharides-through-1-6-anhydro-n-acetyl-%C3%AE-d-glucosamine
#11
Tatiana V Tyrtysh, Elena Yu Korchagina, Ivan M Ryzhov, Nicolai V Bovin
Gram scale synthesis of A (type 2) and B (type 2) tetrasaccharides in the form of 3-aminopropyl glycosides is proposed starting from 3-O-benzoyl-1,6-anhydro-N-acetylglucosamine. Its galactosylation followed by re-protection gave lactosamine derivative with single free 2'-OH group in total yield 75%. Standard fucosylation and next run of re-protection in total yield 88% gave a trisaccharide Fuc-Gal-anhydroGlcNAc with single free 3'-OH group. Its standard α-galactosylation gave protected B (type 2) tetrasaccharide...
June 27, 2017: Carbohydrate Research
https://www.readbyqxmd.com/read/28738264/evidence-of-anomalous-behavior-of-intermolecular-interactions-at-low-concentration-of-methanol-in-ethanol-methanol-binary-system
#12
K Nilavarasi, Thejus R Kartha, V Madhurima
At low concentrations of methanol in a binary system of ethanol and methanol, uniquely complex molecular interactions are reported here. Previous studies indicate that ethanol molecules form aggregates held together by hydrogen bonding (O-H-O) and also dispersive forces. Addition of small amount of methanol tends to break the hydrogen bond network of ethanol due to the larger polarity of methanol. This leads to the ethanol molecules becoming somewhat isolated from each other within a scaffolding network of methanol molecules, as seen from the present molecular dynamics simulations...
July 15, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28738263/prenatal-exposure-to-pm2-5-and-birth-weight-a-pooled-analysis-from-three-north-american-longitudinal-pregnancy-cohort-studies
#13
Maria José Rosa, Ashley Pajak, Allan C Just, Perry E Sheffield, Itai Kloog, Joel Schwartz, Brent Coull, Michelle Bosquet Enlow, Andrea A Baccarelli, Kathi Huddleston, John E Niederhuber, Martha María Téllez Rojo, Robert O Wright, Chris Gennings, Rosalind J Wright
A common practice when analyzing multi-site epidemiological data is to include a term for 'site' to account for unmeasured effects at each location. This practice should be carefully considered when site can have complex relationships with important demographic and exposure variables. We leverage data from three longitudinal North American pregnancy cohorts to demonstrate a novel method to assess study heterogeneity and potential combinability of studies for pooled analyses in order to better understand how to consider site in analyses...
July 21, 2017: Environment International
https://www.readbyqxmd.com/read/28738206/a-preliminary-study-on-the-effects-of-lanthanum-iii-on-plant-vitronectin-like-protein-and-its-toxicological-basis
#14
Lihong Wang, Jingfang He, Qing Yang, Xiaodong Li, Haiyan Wei, David D Y Chen, Xiaohua Huang
Vitronectin-like protein (VN) is widely found outside plant plasma membranes. The VN molecular surface contains a large number of active groups that combine strongly with rare earth elements (REEs), which means that VN is a preferential binding target for REEs exhibiting their toxic effects, but the toxicological mechanism remains unknown. This study used transmission electron microscopy, circular dichroism, fluorescence spectrometry, ultraviolet-visible spectroscopy, X-ray photoelectron spectroscopy, and calculational chemistry (homology modeling, molecular dynamics simulation and quantum chemical calculation) to preliminarily investigate the effect of lanthanum [La(III)] as an REE, on the structure of VN and its toxicological mechanism...
July 21, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/28738126/comparing-plasma-phospho-tau-total-tau-and-phospho-tau-total-tau-ratio-as-acute-and-chronic-traumatic-brain-injury-biomarkers
#15
Richard Rubenstein, Binggong Chang, John K Yue, Allen Chiu, Ethan A Winkler, Ava M Puccio, Ramon Diaz-Arrastia, Esther L Yuh, Pratik Mukherjee, Alex B Valadka, Wayne A Gordon, David O Okonkwo, Peter Davies, Sanjeev Agarwal, Fan Lin, George Sarkis, Hamad Yadikar, Zhihui Yang, Geoffrey T Manley, Kevin K W Wang, Shelly R Cooper, Kristen Dams-O'Connor, Allison J Borrasso, Tomoo Inoue, Andrew I R Maas, David K Menon, David M Schnyer, Mary J Vassar
Importance: Annually in the United States, at least 3.5 million people seek medical attention for traumatic brain injury (TBI). The development of therapies for TBI is limited by the absence of diagnostic and prognostic biomarkers. Microtubule-associated protein tau is an axonal phosphoprotein. To date, the presence of the hypophosphorylated tau protein (P-tau) in plasma from patients with acute TBI and chronic TBI has not been investigated. Objective: To examine the associations between plasma P-tau and total-tau (T-tau) levels and injury presence, severity, type of pathoanatomic lesion (neuroimaging), and patient outcomes in acute and chronic TBI...
July 24, 2017: JAMA Neurology
https://www.readbyqxmd.com/read/28737949/effects-of-autogenous-bone-marrow-aspirate-concentrate-on-radiographic-integration-of-femoral-condylar-osteochondral-allografts
#16
Lasun O Oladeji, James P Stannard, Cristi R Cook, Mauricio Kfuri, Brett D Crist, Matthew J Smith, James L Cook
BACKGROUND: Transplantation of fresh osteochondral allografts (OCAs) is an attractive treatment option for symptomatic articular cartilage lesions in young, healthy patients. Because the lack of OCA bone integration can be a cause of treatment failure, methods for speeding and enhancing OCA bone integration to mitigate this potential complication are highly desirable. PURPOSE: To determine if autogenous bone marrow aspirate concentrate (BMC) treatment of large femoral condylar OCAs would be associated with superior radiographic OCA bone integration compared with nontreated allografts during the critical first 6 months after surgery...
July 1, 2017: American Journal of Sports Medicine
https://www.readbyqxmd.com/read/28737941/unveiling-the-catalytic-role-of-b-block-histidine-in-the-n-s-acyl-shift-step-of-protein-splicing
#17
Jon I Mujika, Xabier Lopez
Protein splicing is a post-translational modification that involves the excision of a segment denoted as intein and the joining of its two flanking segments. The process is auto-catalytic, making inteins appealing for many applications in biotechnology, bioengineering, or medicine. The canonical mechanism of protein splicing is composed of four sequential steps, and is initialized by an N-S or N-O acyl shift to form a linear ester. It is well established that a histidine, the most conserved amino acid in all inteins catalyzes this initial step, even though its role remains to be understood...
July 24, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28737924/linking-ph-temperature-and-k-concentration-for-dna-i-motif-formation
#18
Tra Nguyen, Claudette Fraire, Richard D Sheardy
The conformation a particular DNA segment assumes depends upon its sequence context and the environment under which it is prepared. To complement our findings with G-rich sequences related to the human telomere, we have been investigating the pH induced transition from single strand to i-motif for sequences related to the human telomere C-rich strand. We have carried out titrations of (CCCTAA)4 from pH 7.0 to pH 5.0 at temperatures ranging from 15 to 45 (o)C at 115 mM K(+) and at K(+) concentrations ranging from 15 to 315 mM at 25 (o)C...
July 24, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28737917/antagonistic-interplay-between-an-intermolecular-ch%C3%A2-%C3%A2-%C3%A2-o-and-an-intramolecular-oh%C3%A2-%C3%A2-%C3%A2-o-hydrogen-bond-in-a-1-1-complex-between-1-2-cyclohexanedione-and-chloroform-a-combined-matrix-isolation-infrared-and-quantum-chemistry-study
#19
Amit Kumar Samanta, Pujarini Banerjee, Biman Bandyopadhyay, Prasenjit Pandey, Tapas Chakraborty
Matrix isolation infrared spectra of a weak C-H•••O hydrogen bonded complex between the keto-enol form of 1,2-cyclohexanedione (HCHD) and chloroform have been measured. The spectra reveal that the intramolecular O-H•••O H-bond of HCHD is weakened as a result of complex formation, manifesting in prominent blue shift (~23 cm-1) of the νO-H band and red shifts (~7 cm-1) of νC=O bands of the acceptor (HCHD). The νC-H band of donor CHCl3 undergoes a large red shift of ~33 cm-1. Very similar spectral effects are also observed for formation of the complex in CCl4 solution at room temperature...
July 24, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28737861/effects-of-25-hydroxy-vitamin-d-levels-on-the-severity-and-asthma-control-in-school-age-asthma-patients
#20
Merve Havan, Cem H Razi, Ayse D Bulus, Ali O Köksal, Nesibe Andıran
BACKGROUND: The objective was to determine vitamin D levels in patients between the ages 6 and 18 years, followed for asthma, and the relation between vitamin D levels and asthma control and severity. MATERIALS AND METHODS: Patients with asthma and healthy volunteers between the ages 6 and 18 years were enrolled into the study as patient and control groups, respectively. Patient demographic information and clinical findings were recorded; a respiratory function test was performed...
August 1, 2017: Archivos Argentinos de Pediatría
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