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https://www.readbyqxmd.com/read/28340481/metabolic-profiling-of-tyrosine-tryptophan-and-glutamate-in-human-urine-using-gas-chromatography-tandem-mass-spectrometry-combined-with-single-spe-cleanup
#1
Hyun Ju Shin, Na Hyun Park, Wonwoong Lee, Man Ho Choi, Bong Chul Chung, Jongki Hong
The tyrosine, tryptophan, and glutamate metabolic pathways play key roles on pathological state of neuronal functions and the change of their levels in biological systems reflects the progress degree of neuronal diseases. Comprehensive profiling of these metabolites is important to find new biomarkers for diagnosis or prognosis of various neuronal diseases. However, the overall profiling analysis of various neurochemicals in biological sample is confronted with several limitations due to their low concentration and physicochemical properties and the coexistence of matrices...
March 16, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28340309/analytical-techniques-in-lipidomics-state-of-the-art
#2
Kamil Jurowski, Kamila Kochan, Justyna Walczak, Małgorzata Barańska, Wojciech Piekoszewski, Bogusław Buszewski
Current studies related to lipid identification and determination, or lipidomics in biological samples, are one of the most important issues in modern bioanalytical chemistry. There are many articles dedicated to specific analytical strategies used in lipidomics in various kinds of biological samples. However, in such literature, there is lack of articles dedicated to a comprehensive review of the actual analytical methodologies used in lipidomics. The aim of this article is to characterize the lipidomics methods used in modern bioanalysis according to the methodological point of view: 1) chromatography/separation methods, 2) spectroscopic methods and 3) mass spectrometry and also hyphenated methods...
March 24, 2017: Critical Reviews in Analytical Chemistry
https://www.readbyqxmd.com/read/28335577/gc-ms-metabolomic-analysis-to-reveal-the-metabolites-and-biological-pathways-involved-in-the-developmental-stages-and-tissue-response-of-panax-ginseng
#3
Jia Liu, Yang Liu, Yu Wang, Ann Abozeid, Yuan-Gang Zu, Xiao-Ning Zhang, Zhong-Hua Tang
Ginsenosides, the major compounds present in ginseng, are known to have numerous physiological and pharmacological effects. The physiological processes, enzymes and genes involved in ginsenoside synthesis in P. ginseng have been well characterized. However, relatively little information is known about the dynamic metabolic changes that occur during ginsenoside accumulation in ginseng. To explore this topic, we isolated metabolites from different tissues at different growth stages, and identified and characterized them by using gas chromatography coupled with mass spectrometry (GC-MS)...
March 21, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28335448/a-community-multi-omics-approach-towards-the-assessment-of-surface-water-quality-in-an-urban-river-system
#4
David J Beale, Avinash V Karpe, Warish Ahmed, Stephen Cook, Paul D Morrison, Christopher Staley, Michael J Sadowsky, Enzo A Palombo
A multi-omics approach was applied to an urban river system (the Brisbane River (BR), Queensland, Australia) in order to investigate surface water quality and characterize the bacterial population with respect to water contaminants. To do this, bacterial metagenomic amplicon-sequencing using Illumina next-generation sequencing (NGS) of the V5-V6 hypervariable regions of the 16S rRNA gene and untargeted community metabolomics using gas chromatography coupled with mass spectrometry (GC-MS) were utilized. The multi-omics data, in combination with fecal indicator bacteria (FIB) counts, trace metal concentrations (by inductively coupled plasma mass spectrometry (ICP-MS)) and in-situ water quality measurements collected from various locations along the BR were then used to assess the health of the river ecosystem...
March 14, 2017: International Journal of Environmental Research and Public Health
https://www.readbyqxmd.com/read/28335395/essential-oil-composition-and-bioactivities-of-waldheimia-glabra-asteraceae-from-qinghai-tibet-plateau
#5
Ji De, Yan Lu, Lijun Ling, Nan Peng, Yang Zhong
Waldheimia glabra is traditionally used as incense and as an anti-influenza drug by Tibetans in China. Here, we collected W. glabra from the Gangs Rinpoche mountain at an altitude of 5200 m, and analyzed its essential oil by gas chromatography-mass spectrometry (GC-MS) combined with the retention indices (RI). Twenty-seven compounds, representing 72.4% of the total essential oil, were identified, including α-bisabolol (20.2%), valeranone (11.8%), chamazulene (9.9%), spathulenol (8.2%), β-caryophyllene (6...
March 13, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28335075/breastmilk-with-a-high-omega-6-to-omega-3-fatty-acid-ratio-induced-cellular-events-similar-to-insulin-resistance-and-obesity-in-3t3-l1-adipocytes
#6
H Vaidya, S K Cheema
BACKGROUND: An imbalance of omega (n)-3 and n-6 polyunsaturated fatty acids (PUFA) during critical periods of development may have adverse effects on the health of the newborn in later life. OBJECTIVES: We hypothesized that breastmilk with higher n-6 to n-3 PUFA ratio will have higher inflammatory cytokines and initiate cellular events similar to insulin resistance and obesity. METHODS: Breastmilk was collected from healthy women who gave natural birth at full term...
March 23, 2017: Pediatric Obesity
https://www.readbyqxmd.com/read/28334650/ultrasensitive-determination-of-dna-oxidation-products-by-gas-chromatography-tandem-mass-spectrometry-and-the-role-of-antioxidants-in-the-prevention-of-oxidative-damage
#7
Sam Dawbaa, Önder Aybastıer, Cevdet Demir
Oxidative stress is considered as one of the significant causes of DNA damage which in turn contributes to cell death through a series of intermediate processes such as cancer formation, mutation, and aging. Natural sources such as plant and fruit products have provided us with interesting substances of antioxidant activity that could be recruited in protecting the genetic materials of the cells. This study is an effort to discover some of those antioxidants effects in their standard and natural forms by performing an ultrasensitive determination of the products of DNA oxidation using GC-MS/MS...
March 16, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28333057/photocatalytic-degradation-of-tartrazine-dye-using-cuo-straw-sheaf-like-nanostructures
#8
Martha Purnachander Rao, Jerry J Wu, Abdullah M Asiri, Sambandam Anandan
Straw-sheaf-like CuO nanostructures were fruitfully synthesized using a chemical precipitation approach for the photocatalytic degradation assessment of tartrazine. Phase identification, composition, and morphological outlook of prepared CuO nanostructures were established by X-ray diffraction and scanning electron microscopy analysis. The photocatalytic performance of the synthesized CuO nanostructures was appraised in the presence of visible light and the possible intermediates formed during the photocatalytic degradation were analyzed by gas chromatography-mass spectrometry...
March 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
https://www.readbyqxmd.com/read/28332723/evidence-for-persistent-organochlorine-pollutants-in-the-human-adrenal-cortex
#9
Enza Fommei, Roberta Turci, Andrea Ripoli, Silvana Balzan, Fabrizio Bianchi, Luca Morelli, Alessio Coi
Environmental pollutants may act as endocrine disruptors in animals. Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) enter the food chain and may accumulate in the fatty animal tissues, including adrenals. To our knowledge, no previous study has investigated their presence in the human normal adrenal (NA) cortex and aldosterone-producing adenomas (APA). Surgical fragments of APA from 11 patients and NA from 8 kidney donors were analyzed for 16 PCBs congeners and 10 OCPs. A Matrix Solid-Phase Dispersion (MSPD) method for simultaneous determination of the target compounds in cortex homogenates was developed...
March 23, 2017: Journal of Applied Toxicology: JAT
https://www.readbyqxmd.com/read/28332307/ethanol-concentration-in-56-refillable-electronic-cigarettes-liquid-formulations-determined-by-headspace-gas-chromatography-with-flame-ionization-detector-hs-gc-fid
#10
Justin L Poklis, Carl E Wolf, Michelle R Peace
Personal battery powered vaporizers or electronic cigarettes were developed as an alternative to traditional cigarettes. The modern electronic cigarettes were patented in 2004 by Hon Lik in China. In May 2016, the US Food and Drug Administration (FDA) imposed regulatory statutes on e-cigarettes and their liquid formulations (e-liquids); prior to that, they were unregulated. E-liquids are typically composed of propylene glycol and/or glycerin, flavoring component(s), and active ingredient(s), such as nicotine...
March 23, 2017: Drug Testing and Analysis
https://www.readbyqxmd.com/read/28332232/paper-based-colorimetric-sensor-system-for-high-throughput-screening-of-c-h-borylation
#11
Han-Sung Kim, Min Sik Eom, Min Su Han, Sunwoo Lee
A paper-based colorimetric sensor system (PBCSS) was developed to detect the amount of bis(pinacolato)diboron (B2Pin2) and applied as a high-throughput screening protocol in Ir-catalyzed C-H borylation. First, 96 ligands were screened for the borylation of benzene, and then 12 of them were selected and tested for five substrates. These reaction mixtures were spotted in the PBCSS, showing a blue-violet color. The value of the gray scale of each reaction was obtained from these colored spots and converted to the extent of conversion of B2Pin2...
March 22, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28330580/biochemical-and-clinical-profiles-of-52-tunisian-patients-affected-by-zellweger-syndrome
#12
Fahmi Nasrallah, Wiem Zidi, Moncef Feki, Samia Kacem, Neji Tebib, Naziha Kaabachi
BACKGROUND: Zellweger syndrome (ZS) is a peroxisome biogenesis disorder attributed to a mutation of the PEX genes family. The incidence of this disease in Africa and the Arab world remains unknown. This contribution is aimed at describing the clinical phenotype and biochemical features in Tunisian patients with ZS in order to improve the detection and management of this severe disorder. METHODS: A total of 52 patients diagnosed with ZS and 60 age- and sex-matched healthy controls were included in this study...
February 17, 2017: Pediatrics and Neonatology
https://www.readbyqxmd.com/read/28330531/determination-of-ethanol-in-kombucha-products-single-laboratory-validation
#13
Blake Ebersole, Ying Liu, Rich Schmidt, Matt Eckert, Paula Brown
Kombucha is a fermented non-alcoholic beveragethat has drawn government attention due to thepossible presence of excess ethanol (>0.5%alcohol by volume; ABV). A validated methodthat provides better precision and accuracy formeasuring ethanol levels in kombucha is urgentlyneeded by the kombucha industry. The currentstudy validated a method for determining ethanolcontent in commercial kombucha products. Theethanol content in kombucha was measuredusing headspace gas chromatography with flameionization detection (GC-FID)...
February 21, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/28330527/validation-of-multiresidue-method-for-analysis-of-31-pesticides-in-rice-using-gas-chromatography-tandem-mass-spectrometry
#14
Rahul Mondal, Ramen Kumar Kole, Anjan Bhattacharyya
Five modified QuEChERS were tested for the multiresidue analysis of 31 pesticides in rice. Rice was spiked with mixturesolution of pesticides at 10 ng/g. Method selection was based on the LODs (sensitivity) and recovery tests (accuracy) of the pesticides. Analysis was done in GC-tandem MS in multiple reaction monitoring mode with a total run time of approximately 37 min. The selected method was validated after spiking rice at 20 and 100 ng/g in rice. The performance characteristics of the method impacted for all selected pesticides were acceptable according to the guidelines for method validation (recovery of 70-120% with an RSD of <20% and r<sup>2</sup> value of ≥0...
February 22, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/28330500/larvicidal-activity-of-phytosteroid-compounds-from-leaf-extract-of-solanum-nigrum-against-culex-vishnui-group-and-anopheles-subpictus
#15
Anjali Rawani, Anushree Singha Ray, Anupam Ghosh, Mary Sakar, Goutam Chandra
BACKGROUND: Vector control is facing a menace due to the appearance of resistance to synthetic insecticides. Insecticides of plant origin may provide appropriate substitute biocontrol techniques in the future. The present study was carried out to investigate the bio control potentiality of active ingredient isolated from chloroform: methanol (1:1 v/v) extract of mature leaves of Solanum nigrum L. (Solanaceae) against early 3rd instar larvae of Culex vishnui group (comprising of Cx. vishnui Theobald, Cx...
March 23, 2017: BMC Research Notes
https://www.readbyqxmd.com/read/28330481/diverse-characteristics-of-the-urinary-excretion-of-amino-acids-in-humans-and-the-use-of-amino-acid-supplementation-to-reduce-fatigue-and-sub-health-in-adults
#16
R H Dunstan, D L Sparkes, M M Macdonald, X Janse De Jonge, B J Dascombe, J Gottfries, C-G Gottfries, T K Roberts
BACKGROUND: The excretion of amino acids in urine represents an important avenue for the loss of key nutrients. Some amino acids such as glycine and histidine are lost in higher abundance than others. These two amino acids perform important physiological functions and are required for the synthesis of key proteins such as haemoglobin and collagen. METHODS: Stage 1 of this study involved healthy subjects (n = 151) who provided first of the morning urine samples and completed symptom questionnaires...
March 23, 2017: Nutrition Journal
https://www.readbyqxmd.com/read/28330298/biodegradation-of-used-engine-oil-by-novel-strains-of-ochrobactrum-anthropi-hm-1-and-citrobacter-freundii-hm-2-isolated-from-oil-contaminated-soil
#17
Haytham M M Ibrahim
Used engine oil (UEO) constitutes a serious environmental problem due to the difficulty of disposal off or reuse. Ten bacterial strains with biodegradation potential were isolated from UEO-contaminated soil sample using enrichment technique. Two strains which exhibited the highest degradation %, 51 ± 1.2 and 48 ± 1.5, respectively, were selected. Based on the morphological, biochemical characteristics and 16S rRNA sequence analysis, they were identified as Ochrobactrum anthropi HM-1 (accession no: KR360745) and Citrobacter freundii HM-2 (accession no: KR360746)...
December 2016: 3 Biotech
https://www.readbyqxmd.com/read/28330281/evaluation-of-bioactive-secondary-metabolites-from-endophytic-fungus-pestalotiopsis-neglecta-bab-5510-isolated-from-leaves-of-cupressus-torulosa-d-don
#18
Deeksha Sharma, Avijit Pramanik, Pavan Kumar Agrawal
Six endophytic fungi were isolated from Cupressus torulosa D.Don and identified phenotypically and genotypically. The fungal cultures were further grown and the culture was extracted by two organic solvents methanol and ethyl acetate. The screening was carried out using the agar well diffusion method against human pathogen such as Escherichia coli, Salmonella typhimurium, Bacillus subtilis and Staphylococcus aureus. Isolated strain of Pestalotiopsis sp. was showing prominent antibacterial activity. The crude methanol and ethyl acetate extract of Pestalotiopsis sp...
December 2016: 3 Biotech
https://www.readbyqxmd.com/read/28330171/purification-and-characterization-of-endo-%C3%AE-1-4-d-glucanase-from-trichoderma-harzianum-strain-hzn11-and-its-application-in-production-of-bioethanol-from-sweet-sorghum-bagasse
#19
Zabin K Bagewadi, Sikandar I Mulla, Harichandra Z Ninnekar
An acidophilic-solvent-thermostable endo β-1,4-D-glucanase produced from a potential Trichoderma harzianum strain HZN11 was purified to homogeneity by DEAE-Sepharose and Sephadex G-100 chromatography with 33.12 fold purification with specific activity of 66.25 U/mg and molecular mass of ~55 kDa. The optimum temperature and pH were 60 °C and 5.5 retaining 76 and 85 % of activity after 3 h, respectively. It showed stability between pH 4.5-6.0 and temperature between 50-70 °C indicating thermostability...
June 2016: 3 Biotech
https://www.readbyqxmd.com/read/28330143/biodegradation-of-two-organophosphorus-pesticides-in-whole-corn-silage-as-affected-by-the-cultured-lactobacillus-plantarum
#20
Ying-Hua Zhang, Di Xu, Xin-Huai Zhao, Yao Song, Yan-Le Liu, Hong-Nan Li
Biodegradation of the pesticides is considered as one of the safest and cheapest ways. The aim of the present study was to reveal if the inoculated Lactic acid bacteria widely used in silage could provide beneficial safety to guarantee dairy feedstuffs and fresh milk. Organophosphorus pesticides (OPPs) degradation in whole corn silage was investigated. Two OPPs, chlorpyrifos and phorate, were added to the whole corn, which was inoculated with L. plantarum 1.0315, L. plantarum 1.0624, L. plantarum 1.0622 and their combination at room temperature for 10 weeks...
June 2016: 3 Biotech
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