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https://www.readbyqxmd.com/read/28817836/sitting-physical-activity-and-serum-oestrogen-metabolism-in-postmenopausal-women-the-women-s-health-initiative-observational-study
#1
Hannah Oh, Hannah Arem, Charles E Matthews, Nicolas Wentzensen, Kerryn W Reding, Louise A Brinton, Garnet L Anderson, Sally B Coburn, Jane A Cauley, Chu Chen, Deborah Goodman, Ruth M Pfeiffer, Roni T Falk, Xia Xu, Britton Trabert
BACKGROUND: Prolonged sitting and lower levels of physical activity have been associated with increased levels of parent oestrogens (oestrone and oestradiol), the key hormones in female cancers, in postmenopausal women. However, it is unknown whether sitting and physical activity are associated with circulating oestrogen metabolite levels. METHODS: Among 1804 postmenopausal women enrolled in the Women's Health Initiative Observational Study, 15 serum oestrogens/oestrogen metabolites were quantified using liquid chromatography-tandem mass spectrometry...
August 17, 2017: British Journal of Cancer
https://www.readbyqxmd.com/read/28817663/discordance-in-the-diagnosis-of-diabetes-comparison-between-hba1c-and-fasting-plasma-glucose
#2
Lan T Ho-Pham, Uyen D T Nguyen, Truong X Tran, Tuan V Nguyen
OBJECTIVE: HbA1c has been introduced as a complementary diagnostic test for diabetes, but its impact on disease prevalence is unknown. This study evaluated the concordance between HbA1c and fasting plasma glucose (FPG) in the diagnosis of diabetes in the general population. MATERIALS AND METHODS: The study was designed as a population based investigation, with participants being sampled from the Ho Chi Minh City, Vietnam. Blood samples were collected after overnight fasting and analyzed within 4 hours after collection...
2017: PloS One
https://www.readbyqxmd.com/read/28817267/flavoring-chemicals-and-aldehydes-in-e-cigarette-emissions
#3
Skylar Klager, Jose Vallarino, Piers MacNaughton, David C Christiani, Quan Lu, Joseph G Allen
Regulations on e-cigarettes in the U.S. do not provide guidelines on the chemical content of e-cigarette liquids. We evaluated emissions of aldehydes and flavoring chemicals in e-cigarette vapor under typical usage conditions. We selected 24 e-cigarette flavors from the top selling disposable e-cigarette brands. E-cigarettes were connected to a pump drawing air for two second puffs with sixty-second intervals between puffs. The vapor was analyzed for the presence of aldehydes using high-performance liquid chromatography-ultraviolet detector and for the presence of flavoring chemicals with gas chromatography and an electron capture detector...
August 17, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28817233/evaluation-and-quantitative-analysis-of-11-compounds-in-morinda-officinalis-using-ultra-high-performance-liquid-chromatography-and-photodiode-array-detection-coupled-with-chemometrics
#4
Xiangsheng Zhao, Weijun Kong, Yakui Zhou, Jianhe Wei, Meihua Yang
Morinda officinalis (Rubiaceae) is a traditional Chinese medicine widely used for the treatment of impotence and osteoporosis in clinical therapy. In the present study, a rapid and simple ultra high performance liquid chromatography with photodiode array detection method was developed and validated for the simultaneous determination of 11 bioactive compounds in M. officinalis. This assay method was validated with respect to linearity (R(2)( ) > 0.9991), precision, repeatability, limit of detection, limit of quantification, and accuracy (with observed recovery rates between 94...
August 17, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28817228/isolation-of-the-new-antiplasmodial-butanolide-malleastrumolide-a-from-a-malleastrum-sp-meliaceae-from-madagascar
#5
Yongle Du, Alexander K Abedi, Ana Lisa Valenciano, Maria L Fernández-Murga, Maria B Cassera, Vincent E Rasamison, Wendy L Applequist, James S Miller, David G I Kingston
An extract of a Malleastrum sp. (Meliaceae) collected in Madagascar by the Madagascar International Cooperative Biodiversity Group was found to have antimalarial activity, with an IC50 value between 2.5 and 5 μg/mL. After purification by liquid-liquid partition, chromatography on a Diaion open column, C-18 SPE and C-18 reverse phase HPLC, the new butanolide malleastrumolide A was isolated. The structure of malleastrumolide A was determined by mass spectrometry, NMR and ECD. The double bond position was determined by cross-metathesis and mass spectrometry...
August 17, 2017: Chemistry & Biodiversity
https://www.readbyqxmd.com/read/28816641/preparation-of-recombinant-human-thymic-stromal-lymphopoietin-protein
#6
Yanlu Zhang, Liehua Wu, Jingai Yu, JianFeng Mei, Yu Yi, JianShu Chen, Guoqing Ying
Human thymic stromal lymphopoietin (hTSLP) protein plays a central role in inflammation. Characterizing properties of hTSLP requires a recombinant overexpression system that produces correctly folded, active hTSLP. In this report, an efficient overexpression system for production of hTSLP was developed. We constructed expression plasmids of the full-length hTslp gene with or without the signal peptide and transformed the plasmids into E. coli. The design of the recombinant proteins included an N-terminal His-tag, which facilitated purification...
August 17, 2017: Preparative Biochemistry & Biotechnology
https://www.readbyqxmd.com/read/28816622/obtention-and-characterization-of-the-recombinant-simian-interleukin-15-in-escherichia-coli-for-the-preclinical-assessment-of-an-il-15-based-therapeutic-vaccine
#7
Yunier Rodríguez-Álvarez, Klaudia Martínez-Cordovez, Alexey Llopiz-Arzuaga, Yassel Ramos-Pérez, Vladimir Besada-Pérez, Dayana García-Lines, Alicia Santos-Savio
Recombinant simian IL-15 (siIL-15) was obtained for the preclinical assessment of an anti-human IL-15 vaccine. For this purpose, the cDNA from peripheral blood mononuclear cells of a Macaca fascicularis monkey was cloned into a pIL-2 vector. The siIL-15 was expressed in E. coli strain W3110 as an insoluble protein which accounted for 13% of the total cellular proteins. Inclusion bodies were solubilized in an 8 M urea solution, which was purified by ion exchange and reverse phase chromatography up to 92% purity...
August 17, 2017: Preparative Biochemistry & Biotechnology
https://www.readbyqxmd.com/read/28816534/seven-familial-dysalbuminemic-hyperthyroxinemia-cases-in-three-unrelated-japanese-families-and-high-performance-liquid-chromatography-analysis-of-the-thyroxine-binding-profile
#8
Hidekazu Nagano, Yoshinori Nakagawa, Naofumi Ishikawa, Yuya Watanabe, Yui Miyabayashi, Akitoshi Nakayama, Masanori Fujimoto, Eri Komai, Akina Shiga, Ai Tamura, Takashi Kono, Tomoko Takiguchi, Seiichiro Higuchi, Ikki Sakuma, Naoko Hashimoto, Sawako Suzuki, Hisashi Koide, Kotaro Yokote, Tomoaki Tanaka
OBJECTIVE: Familial dysalbuminemic hyperthyroxinemia (FDH) is caused by abnormal human serum albumin (HSA) with an increased thyroxine (T4) affinity leading to euthyroid hyperthyroxinemia. One- and two-step immunoassay of serum samples from FDH patients (e.g., Japanese patients) with the HSA R218P mutation can yield false-positive free thyroxine (FT4) results. Therefore, it is difficult to distinguish FDH from syndrome of inappropriate secretion of thyroid-stimulating hormone (e.g., syndrome of resistance to thyroid hormone, thyroid-stimulating hormone [TSH]-producing pituitary adenoma), even when multiple assays are used...
August 17, 2017: Endocrine Practice
https://www.readbyqxmd.com/read/28816401/study-of-organic-acids-in-schisandrae-chinensis-fructus-after-vinegar-processing
#9
Fangzhou Yin, Hui Dai, Lin Li, Tuling Lu, Weidong Li, Baochang Cai, Wu Yin
The ripened fruit of Schisandrae Chinensis Fructus has unique medical properties in Chinese medicine. It is commonly used after vinegar steaming. Vinegar steaming changes the color of Schisandrae Chinensis Fructus from red to black and enhances its acidic and astringent properties. Lignans are the well-investigated components in this herb. However, Schisandrae Chinensis Fructus is acidic in the theory of Chinese medicine, and whether vinegar processing changes its organic acid components remains largely unknown...
August 17, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28816397/a-flow-through-column-electrolytic-cell-for-supercritical-fluid-chromatography
#10
Kazuhiro Yamamoto, Tatsuya Ueki, Naoyuki Higuchi, Kouji Takahashi, Akira Kotani, Hideki Hakamata
A novel flow-through column electrolytic cell was proposed as a detector to obtain current signals for supercritical fluid chromatography. The electrochemical cell consisted of two electrodes and its holder, and a working and a counter electrode were fabricated from 192 carbon strings, which were composed of 400 carbon fibers of 10 μm in diameter filled into a heat-shrinkable tube. These electrodes were placed in the center of a holder made from polyether ether ketone blocks and they were separated by polytetrafluoroethylene membrane filters...
August 17, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28816318/a-soluble-star-shaped-silsesquioxane-cored-polymer-towards-novel-stabilization-of-ph-dependent-high-internal-phase-emulsions
#11
Yuxiu Xing, Jun Peng, Kai Xu, Shuxi Gao, Xuefeng Gui, Shengyuan Liang, Longfeng Sun, Mingcai Chen
A well-defined pH-responsive star-shaped polymer containing poly(N,N-dimethylaminoethyl methacrylate) (PDMA) arms and a cage-like methacryloxypropyl silsesquioxane (CMSQ-T10) core was used as an interfacial stabilizer for emulsions consisting of m-xylene and water. We explored the properties of the CMSQ/PDMA star-shaped polymer using the characteristic results of nuclear magnetic resonance (NMR) spectroscopy, size exclusion chromatography (SEC), dynamic light scattering (DLS), and zeta potential and conductivity measurements...
August 17, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28816294/-optimization-of-alkaline-hydrolysis-based-on-the-side-chain-of-diethyl-ester-4-amino-n-5-formyl-n-8-n-10-dideazatetrahydrofolic-acid
#12
M M Yuan, M Wang, J Y Liu, Z L Zhang
OBJECTIVE: To optimize and establish the best hydrolysis method of diethyl ester 4-amino-N(5)-formyl-N(8), N(10)-dideazatetrahydrofolate through the optimization of simple compound of diethyl N-(4-aminobenzoyl)-L-glutamate. METHODS: To increase the low yield of hydrolysis reaction of diethyl ester 4-amino-N(5)-formyl-N(8), N(10)-dideazatetrahydrofolate due to the by-products and difficult purification, we studied the effect of NaOH and KOH, two kinds of alkalis, three concentrations between 0...
August 18, 2017: Beijing da Xue Xue Bao. Yi Xue Ban, Journal of Peking University. Health Sciences
https://www.readbyqxmd.com/read/28815938/optimization-of-recombinant-%C3%AE-glucuronidase-hydrolysis-and-quantification-of-eight-urinary-cannabinoids-and-metabolites-by-liquid-chromatography-tandem-mass-spectrometry
#13
Cristina Sempio, Karl B Scheidweiler, Allan J Barnes, Marilyn A Huestis
Prolonged urinary cannabinoid excretion in chronic frequent cannabis users confounds identification of recent cannabis intake that may be important in treatment, workplace, clinical, and forensic testing programs. In addition, differentiation of synthetic Δ9-tetrahydrocannabinol (THC) intake from cannabis plant products might be an important interpretive issue. THC, 11-hydroxy-THC (11-OH-THC) and 11-nor-9-carboxy-THC (THCCOOH) urine concentrations were evaluated during previous controlled cannabis administration studies following tandem alkaline/E...
June 14, 2017: Drug Testing and Analysis
https://www.readbyqxmd.com/read/28815810/proteome-characterization-of-human-pancreatic-cyst-fluid-from-intraductal-papillary-mucinous-neoplasm-by-lc-ms-ms
#14
Joonho Park, Dohyun Han, Misol Do, Jongmin Woo, Joseph I Wang, Youngmin Han, Wooil Kwon, Sun-Whe Kim, Jin-Young Jang, Youngsoo Kim
RATIONALE: In recent years, the molecular components of pancreatic cyst fluid has been used for diagnosis and prognosis. Because the protein markers that are currently used in clinical tests are unreliable, proteomic studies to find new protein markers are being conducted. However, such researches have been limited due to the complexity of pancreatic cyst fluid and the immaturity of proteomic techniques. METHODS: To overcome these limitations and provide a pancreatic cyst proteome dataset, we examined cyst fluid proteome with tandem mass spectrometry...
August 15, 2017: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/28815745/recent-developments-in-open-tubular-capillary-electrochromatography-from-2016-2017
#15
REVIEW
Faustino M Tarongoy, Paul R Haddad, Joselito P Quirino
Interest in open-tubular capillary electrochromatography (OT-CEC) continues to thrive because of the inherent advantage of OT-CEC combining the high efficiency of capillary electrophoresis and the high selectivity of high performance liquid chromatography. For the period 2016 to 2017, novel materials have been developed as first-time stationary phases for OT-CEC and are grouped in this review as polymer-based materials, frameworks, nanoparticles, graphene-based materials, and biomaterials. Coating and fabrication methods mostly rely on covalent coating strategies while non-covalent immobilisation strategies like electrostatic assembly are notably still being employed...
August 16, 2017: Electrophoresis
https://www.readbyqxmd.com/read/28815733/comparison-of-the-pharmacokinetic-profiles-of-two-different-amphotericin-b-formulations-in-healthy-dogs
#16
B Bingöl, T Bakirel
This study was conducted to compare the pharmacokinetic profiles of conventional (Fungizone(®) ) and liposomal amphotericin B (AmBisome(®) ) formulations in order to predict their therapeutic properties, and evaluate their potential differences in veterinary treatment. For this purpose, twelve healthy mixed breed dogs received both drugs at a dose of 0.6 mg/kg by intravenous infusion over a 4-min period in a total volume of 40 ml. Blood samples were collected at 0, 0.5, 1, 1.5, 2, 3, 4, 8, 12, 24, 48, 72 and 96 hr after dosing, and concentrations of drug in plasma were determined by high-performance liquid chromatography (HPLC)...
August 16, 2017: Journal of Veterinary Pharmacology and Therapeutics
https://www.readbyqxmd.com/read/28815697/case-control-study-of-chronic-low-level-exposure-of-inorganic-arsenic-species-and-non-melanoma-skin-cancer
#17
Tae-Hoon Kim, Jeong-Wook Seo, Young-Seoub Hong, Ki-Hoon Song
A significant relationship between arsenic exposure and non-melanoma skin cancer (NMSC) is well known. The toxicity of arsenics which develop NMSC is dependent on their species. Accordingly, total arsenic levels are unreliable for risk assessment of NMSC. However, there are few studies on quantitative exposure assessment of arsenic species in NMSC patients. To validate the contribution of each arsenic species to NMSC, we compared the creatinine-adjusted urinary concentration of arsenic species in NMSC patients and community controls...
August 16, 2017: Journal of Dermatology
https://www.readbyqxmd.com/read/28815689/medication-adherence-in-patients-with-apparent-resistant-hypertension-findings-from-the-sympathy-trial
#18
R L de Jager, E M van Maarseveen, M L Bots, P J Blankestijn
INTRODUCTION: Hypertension is only controlled in approximately 35% of the patients, which could be partially due to non-adherence. Recently, bioanalytical assessment of adherence to blood pressure (BP) lowering drugs has gaining interest. Our aim was to explore possible determinants of non-adherence in treatment resistant hypertension, assessed by objective screening for antihypertensive agents in serum. Secondary aim was to study the effect of adherence on the change in BP. METHODS: This project was a sub-study of SYMPATHY; an open-label randomized-controlled trial to assess the effect of renal denervation on BP six months after treatment compared to usual care in patients with resistant hypertension...
August 17, 2017: British Journal of Clinical Pharmacology
https://www.readbyqxmd.com/read/28815606/prospective-study-of-urinary-prostaglandin-e2-metabolite-and-pancreatic-cancer-risk
#19
Yong Cui, Xiao-Ou Shu, Hong-Lan Li, Gong Yang, Wanqing Wen, Yu-Tang Gao, Qiuyin Cai, Nathaniel Rothman, Hui-Yong Yin, Qing Lan, Yong-Bing Xiang, Wei Zheng
The cyclooxygenase 2 (COX-2) pathway is upregulated in many pancreatic cancer cells, and it is believed that carcinogenetic effects of COX2 upregulation are largely through prostaglandin E2 (PGE2) overproduction. We tested this hypothesis by evaluating the association between urinary PGE2 metabolites (PGE-M), a biomarker of in vivo PGE2 overproduction, and pancreatic cancer risk. We conducted a case-control study with 722 subjects (239 cases and 483 controls) nested within two prospective cohort studies, the Shanghai Women's Health Study (SWHS) and Shanghai Men's Health Study (SMHS)...
August 17, 2017: International Journal of Cancer. Journal International du Cancer
https://www.readbyqxmd.com/read/28815507/using-purified-tyrosine-site-specific-recombinases-in-vitro-to-rapidly-construct-and-diversify-metabolic-pathways
#20
Wei Liu, Laura R Tuck, Jon Marles Wright, Yizhi Cai
The site-specific recombinase Cre was previously reported to have in vitro activity. Here, we describe the method of purifying two new tyrosine site-specific recombinases VCre and Dre along with Cre by nickel affinity chromatography. We proved the in vitro function of the VCre and Dre on their respective conditional recombination sites. We also developed a methodology to one-step construct and optimize the productivity of a biosynthetic pathway through the combinatorial integration of promoters into a plasmid-encoded pathway by simply incubating a DNA mixture with recombinase system at 37 °C in vitro...
2017: Methods in Molecular Biology
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