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https://www.readbyqxmd.com/read/28651288/development-of-a-high-performance-liquid-chromatographic-method-for-asiaticoside-quantification-in-different-skin-layers-after-topical-application-of-a-centella-asiatica-extract
#1
Priscila Bianca Rodrigues da Rocha, Bruno Dos Santos Souza, Lígia Marquez Andrade, Ricardo Neves Marreto, Eliana Martins Lima, Stephânia Fleury Taveira
The topical application of Centella asiatica extract has been commonly used for many different purposes but especially for cosmetic use in the treatment of gynoid lipodystrophy. Asiaticoside, the most active component in this extract, is responsible for its therapeutic activities. However, little is known to date about asiaticoside skin penetration. Thus, an analytical method for asiaticoside quantification in different skin layers after the topical application of C. asiatica extract was developed and skin permeation studies were performed with the plant extract to apply the analytical method developed...
June 26, 2017: Planta Medica
https://www.readbyqxmd.com/read/28651210/associations-between-perfluorinated-alkyl-acids-in-blood-and-ovarian-follicular-fluid-and-ovarian-function-in-women-undergoing-assisted-reproductive-treatment
#2
Jessica A McCoy, Jacqueline T Bangma, Jessica L Reiner, John A Bowden, John Schnorr, Michael Slowey, Thomas O'Leary, Louis J Guillette, Benjamin B Parrott
Endocrine disrupting contaminants, in combination with other environmental variables, are associated with altered reproductive health. Assisted reproductive technology (ART) procedures offer valuable opportunities to explore the connections between environmental contaminants in the ovarian microenvironment and measures of fertility, including impaired responsiveness to gonadotropins. Here, we investigate an emerging class of environmental contaminants, the perfluorinated alkyl acids (PFAAs), to determine whether ovarian contaminant levels are associated with measures of ovarian responsiveness and fertility outcomes in a South Carolina population of women undergoing ART...
June 23, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28651190/temporal-dynamics-of-the-compositions-and-activities-of-soil-microbial-communities-post-application-of-the-insecticide-chlorantraniliprole-in-paddy-soils
#3
Meng Wu, Jia Liu, Weitao Li, Ming Liu, Chunyu Jiang, Zhongpei Li
Chlorantraniliprole (CAP) is a newly developed insecticide widely used in rice fields in China. There has been few studies evaluating the toxicological effects of CAP on soil-associated microbes. An 85-day microcosm experiment was performed to reveal the dissipation dynamics of CAP in three types of paddy soils in subtropical China. The effects of CAP on microbial activities (microbial biomass carbon-MBC, basal soil respiration-BSR, microbial metabolic quotient-qCO2, acid phosphatase and sucrose invertase activities) in the soils were periodically evaluated...
June 23, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/28651172/simultaneous-determination-of-cis-permethrin-and-trans-permethrin-in-rat-plasma-and-brain-tissue-using-gas-chromatography-negative-chemical-ionization-mass-spectrometry
#4
Shirin Hooshfar, Darren R Gullick, Michael R Linzey, Tanzir Mortuza, Mona Hamdy Abdel Rahman, Clinton A Rogers, James V Bruckner, Catherine A White, Michael G Bartlett
A sensitive method for the simultaneous determination of cis-permethrin (cis-PERM) and trans-permethrin (trans-PERM) in small volumes (100μL) of rat plasma and brain homogenate was developed, using a liquid-liquid extraction for sample preparation and gas chromatography-negative chemical ionization mass spectrometry (GCNCI-MS) for detection. Quantitation of trace levels of the insecticide in small volumes of biological samples is essential to support toxicokinetic studies in small animals. There are currently no validated methods in the literature for determining cis-PERM and trans- PERM in volumes as low as 100μL of rat plasma or brain homogenate...
June 13, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28651142/fast-pyrolysis-of-durian-durio-zibethinus-l-shell-in-a-drop-type-fixed-bed-reactor-pyrolysis-behavior-and-product-analyses
#5
Y L Tan, A Z Abdullah, B H Hameed
Durian shell (DS) was pyrolyzed in a drop-type fixed-bed reactor to study the physicochemical properties of the products. The experiment was carried out with different particle sizes (up to 5mm) and reaction temperatures (250-650°C). The highest bio-oil yield was obtained at 650°C (57.45wt%) with DS size of 1-2mm. The elemental composition and higher heating value of the feedstock, bio-oil (650°C), and bio-char (650°C) were determined and compared. The compositions of product gases were determined via gas chromatography with thermal conductivity detector...
June 23, 2017: Bioresource Technology
https://www.readbyqxmd.com/read/28651109/separation-of-furostanol-saponins-by-supercritical-fluid-chromatography
#6
Jie Yang, Lingling Zhu, Yang Zhao, Yongwei Xu, Qinglong Sun, Shuchen Liu, Chao Liu, Baiping Ma
Supercritical fluid chromatography (SFC) has good separation efficiency and is suitable for separating weakly polar compounds. Furostanol saponins, as an important kind of steroidal saponins, generally have two sugar chains, which are polar and hydrophilic. The hydroxyl group at the C-22 position of furostanol saponins is active and easily reacts with lower alcohols under appropriate conditions. The separation of hydrophilic furostanol saponins was tested by SFC in this study. The effects of chromatographic conditions on the separation of the mixed furostanol saponins and their hydroxyl derivatives at the C-22 position were studied...
June 19, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28651041/interaction-of-vivo-acac-2-with-human-serum-transferrin-and-albumin
#7
João Costa Pessoa, Isabel Correia, Ielyzaveta Chorna, Isabel Cavaco, Somnath Roy, Maxim L Kuznetsov, Nádia Ribeiro, Gonçalo Justino, Fernanda Marques, Teresa Santos Silva, Marino Santos, Hugo M Santos, José L Capelo, James Doutch
[VO(acac)2] is a remarkable vanadium compound and has potential as a therapeutic drug. It is important to clarify how it is transported in blood, but the reports addressing its binding to serum proteins have been contradictory. We use several spectroscopic and mass spectrometric techniques (ESI and MALDI-TOF), small-angle X-ray scattering and size exclusion chromatography (SEC) to characterize solutions containing [VO(acac)2] and either human serum apotransferrin (apoHTF) or albumin (HSA). DFT and modeling protein calculations are carried out to disclose the type of binding to apoHTF...
June 26, 2017: Chemistry, An Asian Journal
https://www.readbyqxmd.com/read/28651026/binding-of-human-plasminogen-and-high-molecular-mass-kininogen-by-cell-surface-exposed-proteins-of-candida-parapsilosis
#8
Justyna Karkowska-Kuleta, Dorota Zajac, Grazyna Bras, Oliwia Bochenska, Maria Rapala-Kozik, Andrzej Kozik
Pathogenic microbes can recruit to their cell surface human proteins that are components of important proteolytic cascades involved in coagulation, fibrinolysis and innate immune response. Once located at the bacterial or fungal surface, such deployed proteins might be utilized by pathogens to facilitate invasion and dissemination within the host organism by interfering with functionality of these systems or by exploiting specific activity of the bound enzymes. Aim of the study presented here was to characterize this phenomenon in Candida parapsilosis (Ashford) Langeron et Talice - an important causative agent of systemic fungal infections (candidiases and candidemias) in humans...
June 24, 2017: Acta Biochimica Polonica
https://www.readbyqxmd.com/read/28650900/a-high-throughput-hplc-ms-ms-assay-for-the-detection-quantification-and-simultaneous-structural-confirmation-of-136-drugs-and-metabolites-in-human-urine
#9
Jacek Klepacki, Baharak Davari, Marion Boulet, Ryan Lizarraga, Uwe Christians
BACKGROUND: Due to its superior sensitivity and specificity, multi-analyte high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) has become the gold standard in clinical toxicology. Although several qualitative and quantitative LC-MS/MS assays on various mass spectrometry platforms have been described in the literature, the majority of these methods either analyze only a limited number of compounds, and/or require tedious and time-consuming sample preparation...
June 22, 2017: Therapeutic Drug Monitoring
https://www.readbyqxmd.com/read/28650653/growth-and-metabolic-responses-of-rice-oryza-sativa-l-cultivated-in-phosphorus-deficient-soil-amended-with-tio2-nanoparticles
#10
Zahra Zahra, Naima Waseem, Rubab Zahra, Hwanhui Lee, Mohsin Ali Badshah, Arshad Mehmood, Hyung-Kyoon Choi, Muhammad Arshad
Plants have natural ability to withstand stress conditions through metabolic adjustments. The present study aimed at investigating effects of Titanium dioxide nanoparticles (TiO2 NPs) application (0, 25, 50, 150, 250, 500 and 750 mg kg-1) in phosphorus deficient soil in terms of growth responses, P contents and metabolic alterations in rice. TiO2 NPs application increased shoot length up to 14.5%. Phosphorus contents in rice roots, shoots, and grains were increased by 2.6-, 2.4-, and 1.3-fold, respectively at 750 mg kg-1 of TiO2 NPs...
June 26, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28650464/%C3%AE-catenin-downregulates-dicer-to-promote-ovarian-cancer-metastasis
#11
S K Y To, A S C Mak, Y M Eva Fung, C-M Che, S-S Li, W Deng, B Ru, J Zhang, A S T Wong
Ovarian cancer is a nearly uniform lethal disease and its highly aggressive metastatic phenotype portends a poor prognosis. Lack of a well-controlled, relevant experimental model has been a major obstacle to identifying key molecules causing metastasis. Here we describe the creation of a new isogenic model of spontaneous human ovarian cancer metastasis exhibiting opposite phenotypes-highly metastatic (HM) and non-metastatic (NM)-both in vitro and in vivo. HM was unique in its ability to metastasize consistently to the peritoneum, mimicking the major dissemination route of human ovarian cancer...
June 26, 2017: Oncogene
https://www.readbyqxmd.com/read/28650333/simultaneous-determination-of-ace-inhibitors-and-dexibuprofen-in-active-pharmaceutical-ingredient-formulations-and-human-serum-by-rp-hplc
#12
Aisha Sana, Safila Naveed, Fatima Qamar, Sadia Shakeel
The contemporary work describes a rapid and cost effective reversed phase High Performance Liquid Chromatography (RP-HPLC) method for the quantification of Captopril, Lisinopril and Dexibuprofen (DXP) simultaneously in dosage formulations, active pharmaceutical ingredients and human serum. The chromatographic system included LC-20A pump, Sil-20A auto sampler and SPD-20A UV/visible detector. The estimation was carried out by using a C18 (5μm, 250 ×4.6 mm) column with mobile phase methanol: water (80:20 v/v, pH 3...
March 2017: Pakistan Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/28650234/antinociceptive-and-respiratory-effects-following-application-of-transdermal-fentanyl-patches-and-assessment-of-brain-%C3%AE-opioid-receptor-mrna-expression-in-ball-pythons
#13
Rima J Kharbush, Allison Gutwillig, Kate E Hartzler, Rebecca S Kimyon, Alyssa N Gardner, Andrew D Abbott, Sherry K Cox, Jyoti J Watters, Kurt K Sladky, Stephen M Johnson
OBJECTIVE To quantify plasma fentanyl concentrations (PFCs) and evaluate antinociceptive and respiratory effects following application of transdermal fentanyl patches (TFPs) and assess cerebrospinal μ-opioid receptor mRNA expression in ball pythons (compared with findings in turtles). ANIMALS 44 ball pythons (Python regius) and 10 turtles (Trachemys scripta elegans). PROCEDURES To administer 3 or 12 μg of fentanyl/h, a quarter or whole TFP (TFP-3 and TFP-12, respectively) was used. At intervals after TFP-12 application in snakes, PFCs were measured by reverse-phase high-pressure liquid chromatography...
July 2017: American Journal of Veterinary Research
https://www.readbyqxmd.com/read/28650205/investigation-of-the-hepatoprotective-effect-of-prunus-mume-sieb-et-zucc-extract-in-a-mouse-model-of-alcoholic-liver-injury-through-high-resolution-metabolomics
#14
Adnan Khan, Jeong Hoon Pan, Seongha Cho, Sojung Lee, Young Jun Kim, Youngja H Park
This study aimed to identify the changes in the metabolomics profile of liver damage caused by alcohol consumption and verify beneficial effect of Prunus mume Sieb. et Zucc extract (PME) in protection of alcohol-induced injury by attenuating the level of identified metabolites. Mice were treated with PME and saline or untreated once daily for 5 days, followed by alcohol injection. The plasma samples were analyzed using liquid chromatography-mass spectrometry-based high-resolution metabolomics followed by a multivariate statistical analysis using MetaboAnalyst 3...
June 26, 2017: Journal of Medicinal Food
https://www.readbyqxmd.com/read/28650151/orthogonal-comparison-of-gc-ms-and-1-h-nmr-spectroscopy-for-short-chain-fatty-acid-quantitation
#15
Jingwei Cai, Jingtao Zhang, Yuan Tian, Limin Zhang, Emmanuel Hatzakis, Kristopher W Krausz, Philip B Smith, Frank J Gonzalez, Andrew D Patterson
Short chain fatty acids (SCFAs) are important regulators of host physiology and metabolism and may contribute to obesity and associated metabolic diseases. Interest in SCFAs has increased in part due to the recognized importance of how production of SCFAs by the microbiota may signal to the host. Therefore, reliable, reproducible, and affordable methods for SCFA profiling are required for accurate identification and quantitation. In the current study, four different methods for SCFA (acetic acid, propionic acid, and butyric acid) extraction and quantitation were compared using two independent platforms including gas chromatography coupled with mass spectrometry (GC-MS) and (1)H nuclear magnetic resonance (NMR) spectroscopy...
June 26, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28650149/rplc-hilic-and-sfc-with-mass-spectrometry-polarity-extended-organic-molecule-screening-in-environmental-water-samples
#16
Stefan Bieber, Giorgia Greco, Sylvia Grosse, Thomas Letzel
Trace organic compounds are important in environmental analysis, because they impact water quality and introduce potential (eco)toxicological effects. Current analytical methods mostly rely on gas chromatography (GC) or reversed-phase liquid chromatography (RPLC) coupled with (tandem) mass spectrometry. However, neither method can easily separate very polar molecules. This study presents, two chromatographic separation strategies, a serial RPLC- hydrophilic interaction liquid chromatography (RPLC-HILIC) coupling and an analytical scale supercritical fluid chromatography (SFC) system, and validates their separation effectiveness as polarity-extended chromatographic methods for 274 environmentally relevant compounds...
June 26, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28649963/the-effect-of-growth-medium-on-i-escherichia-coli-i-pathway-mirrored-into-gc-ms-profiles
#17
Ileana Andreea Ratiu, Tomasz Ligor, Victor Bocos-Bintintan, Hossam Al-Suod, Tomasz Kowalkowski, Katarzyna Rafińska, Boguslaw Buszewski
Escherichia coli (E. coli) is a gram-negative coliform bacterium that is commonly found in the lower intestine of warm-blooded organisms. Most of the strains are harmless, but some serotypes are pathogenic, meaning they can cause illness, either diarrhea or illness outside of the intestinal tract. The aim of this work was to assess which components are generated in case of E. coli target analysis needed. In this purpose our study intends to emphasize the importance of the cultivability and to prove the crucial role of growth media used in bacteria growing...
June 26, 2017: Journal of Breath Research
https://www.readbyqxmd.com/read/28649931/a-novel-approach-for-application-of-white-rot-fungi-in-wastewater-treatment-under-non-sterile-conditions-immobilization-of-fungi-on-sorghum
#18
Mostafa Zahmatkesh, Henri Spanjers, Jules B van Lier
In this study we tested a new approach to facilitate the application of white rot fungi (WRF) under non-sterile conditions, by introducing grain sorghum as carrier and sole carbon and nutrient source for WRF. To this end, Trametes versicolor was immobilized on sorghum, and its ability to remove humic acid (HA) from synthetic and real industrial wastewater was studied. HA removal was measured as colour reduction and also analysed via size exclusion chromatography (SEC). Under sterile conditions, 80% colour removal was achieved for both synthetic and real wastewater using immobilized WRF on sorghum, without adding any additional carbon or nutrient sources...
June 26, 2017: Environmental Technology
https://www.readbyqxmd.com/read/28649773/synthesis-and-pka-determination-of-new-enantiopure-dimethyl-substituted-acridino-crown-ethers-containing-a-carboxyl-group-useful-candidates-for-enantiomeric-recognition-studies
#19
Tamás Németh, Gergő Dargó, József Levente Petró, Zsófia Petrik, Sándor Lévai, Balázs Krámos, Zoltán Béni, József Nagy, György Tibor Balogh, Péter Huszthy, Tünde Tóth
New enantiopure dimethyl-substituted acridino-18-crown-6 and acridino-21-crown-7 ethers containing a carboxyl group at position 9 of the acridine ring [(S,S)-8, (S,S)-9, (R,R)-10] were synthesized. The pKa values of the new crown ethers [(S,S)-8, (S,S)-9, (R,R)-10] and of an earlier reported macrocycle [(R,R)-2] were determined by UV-pH titrations. Crown ether (S,S)-8 was attached to silica gel by covalent bonds and the enantiomeric separation ability of the newly prepared chiral stationary phase [(S,S)-CSP-12] was studied by high-performance liquid chromatography (HPLC)...
June 26, 2017: Chirality
https://www.readbyqxmd.com/read/28649754/characterization-and-differentiation-of-geometric-isomers-of-3-methylfentanyl-analogs-by-gas-chromatography-mass-spectrometry-liquid-chromatography-mass-spectrometry-and-nuclear-magnetic-resonance-spectroscopy
#20
Tatsuyuki Kanamori, Yuko T Iwata, Hiroki Segawa, Tadashi Yamamuro, Kenji Kuwayama, Kenji Tsujikawa, Hiroyuki Inoue
The cis and trans isomers of 3-methylfentanyl and its three analogs were chemically synthesized, and these compounds were characterized and differentiated by gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS), and nuclear magnetic resonance (NMR) spectroscopy. The cis and trans isomers of the 3-methylfentanyl analogs were completely separated by GC/MS. Although the high temperature of the GC injection port caused thermal degradation of β-hydroxy-3-methylfentanyl, the degradation was completely suppressed by trimethylsilyl derivatization...
June 26, 2017: Journal of Forensic Sciences
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