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https://www.readbyqxmd.com/read/28938786/prediction-of-egg-freshness-during-storage-using-electronic-nose
#1
Samuel M Yimenu, J Y Kim, B S Kim
The aim of the present study was to investigate the potential of a fast gas chromatography (GC) e-nose for freshness discrimination and for prediction of storage time as well as sensory and internal quality changes during storage of hen eggs. All samples were obtained from the same egg production farm and stored at 20 °C for 20 d. Egg sampling was conducted every 0, 3, 6, 9, 12, 16, and 20 d. During each sampling time, 4 egg cartons (each containing 10 eggs) were randomly selected: one carton for Haugh units, one carton for sensory evaluation and 2 cartons for the e-nose experiment...
October 1, 2017: Poultry Science
https://www.readbyqxmd.com/read/28938495/polyphenol-enriched-fractions-of-cyclopia-intermedia-selectively-affect-lipogenesis-and-lipolysis-in-3t3-l1-adipocytes
#2
Babalwa U Jack, Christiaan J Malherbe, Elize L Willenburg, Dalene de Beer, Barbara Huisamen, Elizabeth Joubert, Christo J F Muller, Johan Louw, Carmen Pheiffer
Cyclopia species are increasingly investigated as sources of phenolic compounds with potential as therapeutic agents. Recently, we demonstrated that a crude polyphenol-enriched organic fraction (CPEF) of Cyclopia intermedia, currently forming the bulk of commercial production, decreased lipid content in 3T3-L1 adipocytes and inhibited body weight gain in obese db/db mice. The aim of the present study was to determine whether a more effective product and/or one with higher specificity could be obtained by fractionation of the CPEF by purposely increasing xanthone and benzophenone levels...
September 22, 2017: Planta Medica
https://www.readbyqxmd.com/read/28938494/supercritical-fluid-chromatography-in-natural-product-analysis-an-update
#3
Nora Gibitz Eisath, Sonja Sturm, Hermann Stuppner
The wide chemical diversity of natural products has challenged analysts all over the world and has been a driving force for the development of innovative technologies since decades. In the last years, supercritical fluid chromatography (SFC) has finally emerged from the shadow of liquid chromatography (LC) and gas chromatography (GC) and has become a powerful tool in modern natural product analysis. Whereas in the past the technique had mainly been restricted to a small group of nonpolar compounds, it has largely expanded its suitability in the last years and has demonstrated possibilities without boundaries...
September 22, 2017: Planta Medica
https://www.readbyqxmd.com/read/28938455/bile-acid-alterations-are-associated-with-insulin-resistance-but-not-with-nash-in-obese-subjects
#4
Vanessa Legry, Sven Francque, Joel T Haas, An Verrijken, Sandrine Caron, Oscar Chávez-Talavera, Emmanuelle Vallez, Luisa Vonghia, Eveline Dirinck, Ann Verhaegen, Mostafa Kouach, Sophie Lestavel, Philippe Lefebvre, Luc Van Gaal, Anne Tailleux, Réjane Paumelle, Bart Staels
Context: Bile acids (BA) are signalling molecules controlling energy homeostasis which can be both toxic and protective for the liver. BA alterations have been reported in obesity, insulin resistance (IR) and non-alcoholic steatohepatitis (NASH). However whether BA alterations contribute to NASH independently of the metabolic status is unclear. Objective: To assess BA alterations associated with NASH independently of BMI and IR. Design & Setting: Patients visiting the obesity clinic of the Antwerp University Hospital (a tertiary referral facility) were recruited from 2006 to 2014...
August 4, 2017: Journal of Clinical Endocrinology and Metabolism
https://www.readbyqxmd.com/read/28938132/development-and-validation-of-carbofuran-and-3-hydroxycarbofuran-analysis-by-high-pressure-liquid-chromatography-with-diode-array-detector-hplc-dad-for-forensic-veterinary-medicine
#5
Vagner Gonçalves, Nicolle Queiroz Hazarbassanov, Adriana de Siqueira, Jorge Camilo Florio, Claudia Helena Pastor Ciscato, Paulo Cesar Maiorka, Andre Fukushima, Helenice de Souza Spinosa
Agricultural pesticides used with the criminal intent to intoxicate domestic and wild animals are a serious concern in Veterinary Medicine. In order to identify the pesticide carbofuran and its metabolite 3- hydroxycarbofuran in animals suspected of exogenous intoxication a high pressure liquid chromatography with diode array detector (HPLC-DAD) method was developed and validated in stomach contents, liver, vitreous humor and blood. The method was evaluated using biological samples from seven different animal species...
September 14, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28938131/characterization-of-the-changes-in-eicosanoid-profiles-of-activated-macrophages-treated-with-20-s-ginsenoside-rg3
#6
Jae Won Lee, Yu Ri Choi, Hyuck Jun Mok, Hyun-A Seong, Dae Young Lee, Geum-Soog Kim, Ji Hye Yoon, Kwang Pyo Kim, Hyung Don Kim
In this study, we used ultra-performance liquid chromatography coupled with tandem mass spectrometry to assess the levels of eicosanoids from RAW264.7 macrophages treated with lipopolysaccharides (LPS) and 20(S)-ginsenoside Rg3 (Rg3). The production of nitric oxide (NO) and the secretion of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were increased in inflammatory macrophages treated with LPS. Rg3 treatment, however, decreased the levels of NO, TNF-α, and IL-6 in activated macrophages. Eicosanoids, known as major metabolites correlated with inflammation, have pro- or anti-inflammatory activities...
September 5, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28938049/detection-of-mutations-in-gyrb-using-denaturing-high-performance-liquid-chromatography-dhplc-among-salmonella-enterica-serovar-typhi-and-paratyphi-a
#7
Ruchi Gupta, Rajni Gaind, Laishram Chandreshwor Singh, Bianca Paglietti, Monorama Deb, Salvatore Rubino, John Wain, Seemi Farhat Basir
Background: Fluoroquinolone resistance is mediated by mutations in the quinolone-resistance determining region (QRDR) of the topoisomerase genes. Denaturing high performance liquid chromatography (DHPLC) was evaluated for detection of clinically important mutations in gyrB among Salmonella. Methods: Salmonella Typhi and S. Paratyphi A characterised for mutation in QRDR of gyrA, parC and parE were studied for mutation in gyrB by DHPLC and validated by sequencing...
December 1, 2016: Transactions of the Royal Society of Tropical Medicine and Hygiene
https://www.readbyqxmd.com/read/28937988/differential-effects-of-rice-bran-cultivars-to-limit-salmonella-typhimurium-in-chicken-cecal-in-vitro-incubations-and-impact-on-the-cecal-microbiome-and-metabolome
#8
Peter M Rubinelli, Sun Ae Kim, Si Hong Park, Stephanie M Roto, Nora Jean Nealon, Elizabeth P Ryan, Steven C Ricke
In this study, rice brans from different cultivars (Calrose, Jasmine, and Red Wells) were assessed for their ability to inhibit Salmonella enterica serovar Typhimurium using an in vitro mixed anaerobic culture system containing cecal microbiota obtained from broilers of different ages. Salmonella Typhimurium was added to controls (feed only, cecal only, and feed + cecal material) and treatments (feed + cecal + different rice brans) and S. Typhimurium populations were enumerated at 0, 24, and 48 h. Two experimental conditions were applied 1) unadapted condition in which S...
2017: PloS One
https://www.readbyqxmd.com/read/28937880/detection-of-free-microcystins-in-the-liver-and-muscle-of-freshwater-fish-by-liquid-chromatography-tandem-mass-spectrometry
#9
Xiaobin Hu, Jinyun Ye, Rongfei Zhang, Xiang Wu, Yixiang Zhang, Chenglong Wu
MC analysis of biological tissue is considered to be very difficult due to the lack of validated methods. This is the primary limiting factor for monitoring potential risks in both the flesh of aquatic organisms and the aquatic ecosystem. In this study, an effective method to determine free MCs (MC-LR and MC-RR) in the muscle and liver tissues of freshwater cultured fish was developed using solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC/MS-MS). The extraction solvent, time of extraction, eluent and purification of the extract were optimized...
September 22, 2017: Journal of Environmental Science and Health. Part. B, Pesticides, Food Contaminants, and Agricultural Wastes
https://www.readbyqxmd.com/read/28937864/determination-of-seven-pyrethroid-pesticides-residue-in-vegetables-by-gas-chromatography-using-carboxylated-multi-walled-carbon-nanotubes-as-dispersion-solid-phase-extraction-sorbent
#10
Peng Sun, Yuling Gao, Chong Xu, Yongfu Lian
:A novel carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) dispersive solid phase extraction (d-SPE) method combined with gas chromatography (GC) with ECD detection was developed for the determination of seven pyrethroid pesticides in cucumber, spinach, eggplant, tomato and carrot. We optimized d-SPE conditions including the type and volume of the extractant, the type and amount of the sorbent, and shaking time. Under the optimal conditions, the linear range was from 2.0 to 2000 μg kg(-1). The recoveries were from 88...
September 22, 2017: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/28937796/delay-of-lung-adenocarcinoma-lac-1-development-in-mice-by-dietary-oleic-acid
#11
Mariana Piegari, Elio A Soria, Aldo R Eynard, Mirta A Valentich
Lung cancer is the leading cause of death by cancer, and is a major sanitary concern worldwide. Some nutrients, such as ω-9 fatty acids, have been proposed as anticancer agents. Thus, an olein-enriched diet was assayed in a murine model of lung adenocarcinoma (LAC-1) to evaluate neoplastic and paraneoplastic evolution in BALB/c mice. The organic assimilation of dietary fatty acids was confirmed in liver by gas chromatography. This experimental oleic acid-containing diet increased animal survival and tumour latency (analysed by the Kaplan-Meier method), improving neoplastic evolution and general status, with weak effects on the paraneoplastic syndrome (thymus atrophy, splenomegaly, splenocyte response to mitogen, blood anaemia, and leucocytosis)...
September 22, 2017: Nutrition and Cancer
https://www.readbyqxmd.com/read/28937600/the-gut-microbial-metabolite-trimethylamine-n-oxide-is-present-in-human-cerebrospinal-fluid
#12
Daniele Del Rio, Francesca Zimetti, Paolo Caffarra, Michele Tassotti, Franco Bernini, Furio Brighenti, Andrea Zini, Ilaria Zanotti
Trimethylamine-N-oxide (TMAO) is a small organic molecule, derived from the intestinal and hepatic metabolism of dietary choline and carnitine. Although the involvement of TMAO in the framework of many chronic diseases has been recently described, no evidence on its putative role in the central nervous system has been provided. The aim of this study was to evaluate whether TMAO is present at detectable levels in human cerebrospinal fluid (CSF). CSF was collected for diagnostic purposes from 58 subjects by lumbar puncture and TMAO was quantified by using liquid chromatography coupled with multiple-reaction monitoring mass spectrometry...
September 22, 2017: Nutrients
https://www.readbyqxmd.com/read/28936868/a-microwave-flow-detector-for-gradient-elution-liquid-chromatography
#13
Duye Ye, Weizheng Wang, David Moline, Md Saiful Islam, Feng Chen, Pingshan Wang
This study presents a microwave flow detector for liquid chromatography (LC) applications. The detector is based on a tunable microwave interferometer (MIM) with a vector network analyzer (VNA) for signal measurement and a computer for system control. A microstrip-line based flow cell with a volume of ~0.31 μL was built and incorporated in the MIM. With syringe pump injections, the detector is evaluated by measuring a few common chemicals in DI water at multiple frequencies between 0.98 GHz and 7.09 GHz and shows a minimum detectable quantity (MDQ) of less than 30 ng...
September 22, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28936846/-lignans-from-barks-of-ailanthus-altissima
#14
Dong Liu, Jian Zhang, Shao-Nan Tang, Xiao-Qi Zhang, Wen-Cai Ye
Eleven lignans were isolated from the ethanol extract of the barks of Ailanthus altissima through various column chromatography methods including silica gel, Sephadex LH-20, ODS and HPLC. By physical, chemical and comprehensive spectroscopic methods, their structures were identified as (+)-neoolivil(1), prunustosanan AI (2), (7S,8R)-guaiacyl-glycerol-β-O-4'-neolignan (3), (7R,8S)-guaiacyl-glycerol-β-O-4'-neolignan (4), (7S,8R)-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxypropyl)-2,6-dimethoxyphenoxy]-1,3-propanediol(5), pinnatifidanin B V (6), pinnatifidanin B VI (7), (7R,7'R,7″S,8S,8'S,8″S)-4',4″-dihydroxy-3,3',3″,5-tetramethoxy-7,9':7',9-diepoxy-4,8″-oxy-8,8'-sesquineolignan-7″,9″-diol (8), hedyotol D (9), 5-(2-propenyl)-7-methoxy-2-(3,4-methylenediovxyphenyl)benzofuran (10), and (7R,8S,7'E)-guaiacyl-glycerol-β-O-4'-sinapyl ether(11)...
December 2016: Zhongguo Zhong Yao za Zhi, Zhongguo Zhongyao Zazhi, China Journal of Chinese Materia Medica
https://www.readbyqxmd.com/read/28936796/biosurfactants-produced-by-bacillus-subtilis-a1-and-pseudomonas-stutzeri-na3-reduce-longevity-and-fecundity-of-anopheles-stephensi-and-show-high-toxicity-against-young-instars
#15
Punniyakotti Parthipan, Raja Kumaresan Sarankumar, Anitha Jaganathan, Pandian Amuthavalli, Ranganathan Babujanarthanam, Pattanathu K S M Rahman, Kadarkarai Murugan, Akon Higuchi, Giovanni Benelli, Aruliah Rajasekar
Anopheles stephensi acts as vector of Plasmodium parasites, which are responsible for malaria in tropical and subtropical areas worldwide. Currently, malaria management is a big challenge due to the presence of insecticide-resistant strains as well as to the development of Plasmodium species highly resistant to major antimalarial drugs. Therefore, the present study focused on biosurfactant produced by two bacteria Bacillus subtilis A1 and Pseudomonas stutzeri NA3, evaluating them for insecticidal applications against malaria mosquitoes...
September 21, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28935667/upregulation-of-herv-k-is-linked-to-immunity-and-inflammation-in-pulmonary-arterial-hypertension
#16
Toshie Saito, Kazuya Miyagawa, Shih-Yu Chen, Rasa Tamosiuniene, Lingli Wang, Orr Sharp, Erik Samayoa, Daisuke Harada, Jan-Renier A J Moonen, Aiqin Cao, Pin-I Chen, Jan K Hennigs, Mingxia Gu, Caiyun G Li, Ryan D Leib, Dan Li, Christopher M Adams, Patricia A Del Rosario, Matthew A Bill, Francois Haddad, Jose G Montoya, William Robinson, Wendy J Fantl, Garry P Nolan, Roham T Zamanian, Mark R Nicolls, Charles Y Chiu, Maria E Ariza, Marlene Rabinovitch
Background -Immune dysregulation has been linked to occlusive vascular remodeling in pulmonary arterial hypertension (PAH) that is hereditary, idiopathic or associated with other conditions. Circulating autoantibodies, lung perivascular lymphoid tissue and elevated cytokines have been related to PAH pathogenesis but without clear understanding of how these abnormalities are initiated, perpetuated and connected in the progression of disease. We therefore set out to identify specific target antigens in PAH lung immune complexes as a starting point toward resolving these issues to better inform future application of immunomodulatory therapies...
September 21, 2017: Circulation
https://www.readbyqxmd.com/read/28935577/human-pancreatic-acinar-cells-proteomic-characterization-physiologic-responses-and-organellar-disorders-in-ex-vivo-pancreatitis
#17
Aurelia Lugea, Richard T Waldron, Olga A Mareninova, Natalia Shalbueva, Nan Deng, Hsin-Yuan Su, Diane D Thomas, Elaina K Jones, Scott W Messenger, Jiayue Yang, Cheng Hu, Ilya Gukovsky, Zhenqiu Liu, Guy E Groblewski, Anna S Gukovskaya, Fred S Gorelick, Stephen J Pandol
Knowledge of the molecular mechanisms of acute pancreatitis is largely based on studies using rodents. To assess similar mechanisms in humans, we performed ex vivo pancreatitis studies in human acini isolated from cadaveric pancreata from organ donors. Since data on these human acinar preparations are sparse, we assessed their functional integrity, and cellular and organellar morphology using light, fluorescence and electron microscopy; and their proteome by liquid chromatography-tandem mass spectrometry (LC-MS/MS)...
September 18, 2017: American Journal of Pathology
https://www.readbyqxmd.com/read/28935539/molecular-structure-of-cyclomaltodextrinase-derived-from-amylolytic-lactic-acid-bacterium-enterococcus-faecium-k-1-and-properties-of-recombinant-enzymes-expressed-in-escherichia-coli-and-lactobacillus-plantarum
#18
Kridsada Unban, Apinun Kanpiengjai, Saisamorn Lumyong, Thu-Ha Nguyen, Dietmar Haltrich, Chartchai Khanongnuch
Gene encoding cyclomaltodextrinase (Cdx) from amylolytic lactic acid bacterium Enterococcus faecium K-1 was cloned and nucleotide sequence was analyzed. The open-reading frame consisted of 1767bp encoding 588 deduced amino acids. Consequently, four typically conserved regions of the glycoside hydrolase family 13 were revealed; however, nine exceeding amino acids (DSYQMTDVP) were found at the 282-290 position in comparison to previously reported cyclomaltodextrinases. This difference is believed to have an influence on the substrate specificity of this enzyme...
September 18, 2017: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/28935407/insights-into-the-attenuated-sorption-of-organic-compounds-on-black-carbon-aged-in-soil
#19
Lei Luo, Jitao Lv, Zien Chen, Rixiang Huang, Shuzhen Zhang
Sorption of organic compounds on fresh black carbons (BCs) can be greatly attenuated in soil over time. We examined herein the changes in surface properties of maize straw-derived BCs (biochars) after aged in a black soil and their effects on the sorptive behaviors of naphthalene, phenanthrene and 1,3-dinitrobenzene. Dissolved fulvic and humic acids extracted from the soil were used to explore the role of dissolved organic carbon (DOC) in the aging of biochars. Chromatography analysis indicated that DOC molecules with relatively large molecular weight were preferentially adsorbed on the biochars during the aging processes...
September 18, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28935256/application-of-feedback-control-and-in-situ-milling-to-improve-particle-size-and-shape-in-the-crystallization-of-a-slow-growing-needle-like-active-pharmaceutical-ingredient
#20
Yang Yang, Kanjakha Pal, Andy Koswara, Qingqing Sun, Yuqi Zhang, Justin Quon, Rahn McKeown, Charles Goss, Zoltan K Nagy
Control of crystal size and shape is crucially important for crystallization process development in the pharmaceutical industries. In general crystals of large size and low aspect ratio are desired for improved downstream manufacturability. It can be extremely challenging to design crystallization processes that achieve these targets for active pharmaceutical ingredients (APIs) that have very slow growth kinetics and needle-like morphology. In this work, a batch cooling crystallization process for a GlaxoSmithKline patented API, which is characterized by very slow growth rate and needle morphology, was studied and improved using process analytical technology (PAT) based feedback control techniques and in situ immersion milling...
September 18, 2017: International Journal of Pharmaceutics
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