5,446 results
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2. Visual paper-based sensor for the highly sensitive detection of caffeine in food and biological matrix based on CdTe-nano ZnTPyP combined with chemometrics.
- Author
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Chen H, Liu R, Guo X, Deng G, Xu L, Zhang L, Lan W, Zhou C, She Y, and Fu H
- Subjects
- Animals, Cattle, Colorimetry instrumentation, Humans, Limit of Detection, Tea chemistry, Water analysis, Cadmium Compounds chemistry, Caffeine blood, Colorimetry methods, Metalloporphyrins chemistry, Paper, Quantum Dots chemistry, Tellurium chemistry, Zinc Compounds chemistry
- Abstract
Caffeine naturally occurs in tea and cocoa, which is also used as an additive in beverages and has pharmacological effects such as refreshing, antidepressant, and digestion promotion, but excessive caffeine can cause harm to the human body. In this work, based on the specific response between nano zinc 5, 10, 15, 20-tetra(4-pyridyl)-21H-23H-porphine (nano ZnTPyP)-CdTe quantum dots (QDs) and caffeine, combined with chemometrics, a visual paper-based sensor was constructed for rapid and on-site detection of caffeine. The fluorescence of QDs can be quenched by nano ZnTPyP. When caffeine is added to the system, it can pull nano ZnTPyP off the surface of the QDs to achieve fluorescence recovery through electrostatic attraction and nitrogen/zinc coordination. The detection range is 5 × 10
-11 ~3 × 10-9 mol L-1 , and the detection limit is 1.53 × 10-11 mol L-1 (R2 = 0.9990) (S/N = 3). The paper-based sensor constructed exhibits good results in real samples, such as tea water, cell culture fluid, newborn bovine serum, and human plasma. Therefore, the sensor is expected to be applied to the rapid instrument-free detection of caffeine in food and biological samples.Graphical abstract.- Published
- 2021
- Full Text
- View/download PDF
3. Editors' Introduction: Best Papers from the 19th International Conference on Cognitive Modeling.
- Author
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Stewart TC and de Jong J
- Subjects
- Humans, Caffeine, Cognition
- Abstract
The International Conference on Cognitive Modeling brings together researchers from around the world whose main goal is to build computational systems that reflect the internal processes of the mind. In this issue, we present the five best representative papers on this work from our 19th meeting, ICCM 2021, which was held virtually from July 3 to July 9, 2021. Three of these papers provide new techniques for refining computational models, giving better methods for taking empirical data and producing accurate computational models of the cognitive systems that produce them. The other two papers focus on explanation: using models to elucidate the underlying processes affecting cognition in such diverse domains as logical reasoning and the effects of caffeine., (© 2022 Cognitive Science Society LLC.)
- Published
- 2022
- Full Text
- View/download PDF
4. A rapid method for the assay of methylxanthines alkaloids: Theobromine, theophylline and caffeine, in cocoa products and drugs by paper spray tandem mass spectrometry.
- Author
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Bartella L, Di Donna L, Napoli A, Siciliano C, Sindona G, and Mazzotti F
- Subjects
- Chromatography, High Pressure Liquid methods, Food Analysis methods, Limit of Detection, Pharmaceutical Preparations analysis, Reproducibility of Results, Tandem Mass Spectrometry standards, Cacao chemistry, Caffeine analysis, Tandem Mass Spectrometry methods, Theobromine analysis, Theophylline analysis
- Abstract
A fast method for the determination of methylxanthines in cocoa products and drugs based on PS-MS/MS under MRM condition has been developed. Analyte ions were generated by applying a high voltage on a paper substrate drenched of sample extract using a small volume (∼15 μL) of spray solvent. The gas phase chemistry of the molecules under investigation has been elucidated. The accuracy values of the methodology ranged from 95 to 110%, while the analytical parameters LOQ, LOD, recovery and reproducibility, calculated analyzing spiked samples, confirmed the consistency of the proposed method. Furthermore, real samples have been analyzed both by the developed methodology and by using a classical HPLC-UV approach obtaining comparable values., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
5. Fast analysis of caffeine in beverages and drugs by paper spray tandem mass spectrometry.
- Author
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Taverna D, Di Donna L, Bartella L, Napoli A, Sindona G, and Mazzotti F
- Subjects
- Limit of Detection, Reference Standards, Spectrophotometry, Ultraviolet, Beverages analysis, Caffeine analysis, Pharmaceutical Preparations analysis, Tandem Mass Spectrometry methods
- Abstract
A simple and fast method based on paper spray mass spectrometry for the determination of caffeine in commercial beverages and drugs has been developed; the analyses were carried out in MRM mode, monitoring the transitions m/z 195 → m/z 138 for caffeine and m/z 198 → m/z 140 for the labeled internal standard. To verify the reliability of the proposed approach, a spiked sample (soda drink and paracetamol tablet) with a known amount of caffeine has been prepared and analyzed by PS-MS, providing accuracy values about 100 %; the LOQ and LOD values were calculated at 1.2 and 1.6 μg/mL, respectively. Both beverages and drugs were also analyzed with the classic analytical method based on LC-UV measurements, showing consistent results between the two approaches, thus confirming the reliability of the developed ambient MS determination. Graphical Abstract The assay of caffeine by paper mass spectrometry.
- Published
- 2016
- Full Text
- View/download PDF
6. Study on the paper substrate room temperature phosphorescence of theobromine, caffeine and theophylline and analytical application.
- Author
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Chuan D, Yan-Li W, and Shao-Min S
- Subjects
- Aminophylline analysis, Cacao chemistry, Coffee chemistry, Hydrogen-Ion Concentration, Luminescence, Metals, Heavy, Paper, Spectrometry, Fluorescence, Tea chemistry, Temperature, Caffeine analysis, Theobromine analysis, Theophylline analysis
- Abstract
Paper substrate room temperature phosphorescence (RTP) of theobromine (TB), caffeine (CF) and theophylline (TP) were investigated. The method is based on fast speed quantitative filter paper as substrate and KI-NaAc as heavy atom perturber. Various factors affecting their RTP were discussed in detail. Under the optimum experimental conditions, the linear dynamic range, limit of detection (LOD), and relative standard deviation (R.S.D.) were 14.41 approximately 576.54 ng per spot, 1.14 ng per spot, 4.8% for TB, 5.44 approximately 699.08 ng per spot, 0.78 ng per spot, 1.56% for CF, 7.21 approximately 360.34 ng per spot, 1.80 ng per spot, 3.80% for TP, respectively. The first analytical application for the determination of these compounds was developed. The recovery of standard samples added to commercial products chocolate, tea, coffee and aminophylline is in the range 92.80-106.08%. The proposed method was successfully applied to real sample analysis without separation.
- Published
- 2003
- Full Text
- View/download PDF
7. [Paper chromatography of adenosinetriphosphate, adenosinediphosphate and other phosphorus compounds in caffeine contracture of frog and road rectus muscle].
- Author
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FLECKENSTEIN A, JANKE J, and ELKE M
- Subjects
- Animals, Adenosine Diphosphate, Adenosine Triphosphate metabolism, Anura, Caffeine pharmacology, Chromatography, Chromatography, Paper, Contracture, Muscles metabolism, Phosphorus Compounds
- Published
- 1954
8. Identification of purines on paper chromatograms.
- Author
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CLARKE EG and KALAYCI S
- Subjects
- Humans, Caffeine, Chromatography, Paper, Purines
- Published
- 1963
- Full Text
- View/download PDF
9. Separation of tabletted mixtures of barbiturates, aspirin, phenacetin, caffeine, codeine, and quinine by ion-exchange paper chromatography.
- Author
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STREET HV and NIYOGI SK
- Subjects
- Aspirin chemistry, Barbiturates chemistry, Caffeine chemistry, Chromatography, Chromatography, Ion Exchange, Chromatography, Paper, Codeine chemistry, Ion Exchange Resins, Phenacetin, Quinine chemistry, Tablets chemistry
- Published
- 1962
- Full Text
- View/download PDF
10. Dynamic gas extraction of iodine in combination with a silver triangular nanoplate-modified paper strip for colorimetric determination of iodine and of iodine-interacting compounds
- Author
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Gorbunova, Marina O., Baulina, Anastasiya A., Kulyaginova, Margarita S., Apyari, Vladimir V., Furletov, Aleksei A., Volkov, Pavel A., Bochenkov, Vladimir E., Starukhin, Aleksandr S., and Dmitrienko, Stanislava G.
- Published
- 2019
- Full Text
- View/download PDF
11. Handleable TiO 2 -coated zeolitic material for photodecomposition of caffeine boosted by urine matrix.
- Author
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Alvarez-Aguiñaga EA, Elizalde-González MP, and García-Díaz E
- Subjects
- Titanium, Ultraviolet Rays, Catalysis, Caffeine, Zeolites
- Abstract
The photocatalytic decomposition of caffeine under UV-light irradiation was observed for the first time in a matrix of synthetic urine using granules of hydrogenated and iron-exchanged natural zeolite, coated with two loadings of TiO
2 . A natural clinoptilolite-mordenite blend was used to prepare photocatalytic adsorbents coated with TiO2 nanoparticles. The performance of the obtained materials was tested in the photodegradation of caffeine, a water contaminant of emerging concern. The photocatalytic activity was better in the urine matrix, due to the formation of surface complexes on the TiO2 coating, cation exchange performed by the zeolite support, and use of the carrier electrons in the reduction of ions, affecting recombination of the electrons and holes during photocatalysis. The composite granules maintained photocatalytic activity for at least four cycles, with more than 50% of caffeine removal in the synthetic urine matrix., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)- Published
- 2023
- Full Text
- View/download PDF
12. High-Performance Paper-Based Fluidic Cassette for Mass Spectrometry Analyzing Caffeine and Nicotine Metabolites
- Author
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Yi-Chieh Li, Che-Hsin Lin, and Ming-Hsu Cheng
- Subjects
Electrospray ,Materials science ,Chromatography ,Filter paper ,010401 analytical chemistry ,010402 general chemistry ,Mass spectrometry ,01 natural sciences ,0104 chemical sciences ,Nicotine ,Paper chromatography ,chemistry.chemical_compound ,chemistry ,Ionization ,medicine ,Fluidics ,Caffeine ,medicine.drug - Abstract
This paper develops a high-performance paper-based fluidic cassette for mass spectrometry (MS) analyzing caffeine and nicotine metabolism in urine and hair samples. The device uses a novel two-dimensional paper chromatography to separate the species in the liquid sample and then analyze the metabolic species via the MS using a specially designed paper spray ionization (PSI) mechanism. The paper-based fluidic chip is produced in the laboratory filter paper with the IR laser for patterning the multifunctional paper for sample chromatography and multiple tip for PSI. To enhance the MS detection performance, an integrated sliding cassette with a pair of pinching electrodes is designed for retarding electrospray at the neighboring tooth and simultaneously focusing the main spray plumb for sample ionization. Numerical and experimental results show that the undesired neighboring electrospray plumbs are significantly retarded by the applying electric field at the pinch electrodes. Successfully detecting the caffeine species in the urine sample and the nicotine/cotinine species in the extracted solution of a heavy smoker's hair are demonstrated with the developed device. The developed paper fluidic cassette has shown its potential in the application of drug abuse prevention.
- Published
- 2020
13. Local Purchase Of Medical Stores Ergotamine 1 Mg, Caffeine 110 Mg + Paracetamol 250 Mg & Prochlorprazine 2.5 Mg Tab, Ebastine 10 Mg Tab , Ecg Recording Paper A4 Size 210mm X 295 For Coman Cm -1200a, Efavirenz 600 Mg Tab, Electrocardiograph Paste|Jelly Bo
- Subjects
Stores ,Efavirenz ,Caffeine ,Cardiovascular equipment ,Ergotamine ,Acetaminophen ,Business, international - Abstract
Tenders are invited for Local purchase of medical stores ergotamine 1 mg, caffeine 110 mg + paracetamol 250 mg & prochlorprazine 2.5 mg tab, ebastine 10 mg tab , ecg [...]
- Published
- 2023
14. Visual paper-based sensor for the highly sensitive detection of caffeine in food and biological matrix based on CdTe-nano ZnTPyP combined with chemometrics
- Author
-
Haiyan Fu, Lu Xu, Hengye Chen, Yuanbin She, Rui Liu, Deng Gaoqiong, Wei Lan, Lei Zhang, Chunsong Zhou, and Guo Xiaoming
- Subjects
Paper ,Metalloporphyrins ,Nanochemistry ,chemistry.chemical_element ,02 engineering and technology ,Zinc ,01 natural sciences ,Analytical Chemistry ,Matrix (chemical analysis) ,Chemometrics ,chemistry.chemical_compound ,Limit of Detection ,Caffeine ,Nano ,Quantum Dots ,Cadmium Compounds ,Animals ,Humans ,Detection limit ,Chromatography ,Tea ,Chemistry ,010401 analytical chemistry ,technology, industry, and agriculture ,Water ,021001 nanoscience & nanotechnology ,Fluorescence ,0104 chemical sciences ,Zinc Compounds ,Cattle ,Colorimetry ,Tellurium ,0210 nano-technology - Abstract
Caffeine naturally occurs in tea and cocoa, which is also used as an additive in beverages and has pharmacological effects such as refreshing, antidepressant, and digestion promotion, but excessive caffeine can cause harm to the human body. In this work, based on the specific response between nano zinc 5, 10, 15, 20-tetra(4-pyridyl)-21H-23H-porphine (nano ZnTPyP)-CdTe quantum dots (QDs) and caffeine, combined with chemometrics, a visual paper-based sensor was constructed for rapid and on-site detection of caffeine. The fluorescence of QDs can be quenched by nano ZnTPyP. When caffeine is added to the system, it can pull nano ZnTPyP off the surface of the QDs to achieve fluorescence recovery through electrostatic attraction and nitrogen/zinc coordination. The detection range is 5 × 10−11~3 × 10−9 mol L−1, and the detection limit is 1.53 × 10−11 mol L−1 (R2 = 0.9990) (S/N = 3). The paper-based sensor constructed exhibits good results in real samples, such as tea water, cell culture fluid, newborn bovine serum, and human plasma. Therefore, the sensor is expected to be applied to the rapid instrument-free detection of caffeine in food and biological samples. Graphical abstract
- Published
- 2020
15. Determination of caffeine in saliva by high-performance liquid chromatography: new sampling method for saliva using filter paper.
- Author
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Suzuki Y, Uematsu T, Mizuno A, Fujii K, and Nakashima M
- Subjects
- Adult, Chromatography, High Pressure Liquid methods, Humans, Male, Caffeine analysis, Filtration instrumentation, Saliva analysis
- Abstract
We report an assay method for the determination of salivary caffeine concentrations by high-performance liquid chromatography. A simple, new method for collecting mixed saliva using a piece of filter paper has been developed. An arbitrary amount of saliva is absorbed and a fixed amount of internal standard is added. The mean coefficient of variation of measurements repeated by changing both volumes absorbed and caffeine concentrations of saliva was 5.6% with this method. The detection limit was determined to be 0.5 microgram/ml. Precision of measurements and recoveries did not depend upon the volume of saliva absorbed. Four volunteers were given a capsule of 230 mg caffeine, and saliva was collected by the ordinary method using chemical stimulation with citric acid and by our filter paper absorption methods; the methods were compared. Salivary caffeine concentrations were always lower than plasma concentrations, and there were no big differences between two methods, although salivary concentrations measured by our method was higher, with a significant difference at 1.5 h after dosing. From the practical viewpoint this method would be convenient and sufficiently accurate.
- Published
- 1989
- Full Text
- View/download PDF
16. Comments on the paper: Effect and specificity of certain histamine antagonists studied on the isolated small intestine of the guinea-pig by L. C. Grandjean.
- Author
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KEWITZ H
- Subjects
- Guinea Pigs, Caffeine, Histamine Antagonists, Histamine H1 Antagonists pharmacology, Intestine, Small, Intestines, Theophylline
- Published
- 1951
- Full Text
- View/download PDF
17. [Separation of caffeine, aspirin and phenacetin by electrophoresis on paper].
- Author
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ViettiI-Michelina M
- Subjects
- Aspirin analysis, Caffeine analysis, Phenacetin analogs & derivatives
- Published
- 1956
18. Sub-Parts-per-Trillion Level Detection of Analytes by Superhydrophobic Preconcentration Paper Spray Ionization Mass Spectrometry (SHPPSI MS)
- Author
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Thalappil Pradeep, Pallab Basuri, and Avijit Baidya
- Subjects
Paper ,Analyte ,Spectrometry, Mass, Electrospray Ionization ,Chromatography ,Aqueous solution ,Filter paper ,Chemistry ,Triazines ,Parts-per notation ,Food Contamination ,Equipment Design ,Mass spectrometry ,Surface energy ,Superhydrophobic coating ,Analytical Chemistry ,Milk ,Limit of Detection ,Caffeine ,Animals ,Urea ,Hydrophobic and Hydrophilic Interactions ,Ambient ionization - Abstract
A new kind of ambient ionization method named superhydrophobic preconcentration paper spray ionization mass spectrometry (SHPPSI MS) is introduced, where superhydrophobicity and paper spray mass spectrometry (PS MS) are coupled. The SHPPSI MS requires only microliter amounts of analyte solutions, allows easy sampling procedure, and provides high sensitivity for a diverse array of analytes. It can be used to detect food adulteration at extremely low concentrations. The experimental methodology involves modifying one of the surfaces of a triangularly cut filter paper to make it acquire low surface energy by drop casting a green and ecofriendly superhydrophobic coating material over it followed by drying. A micrometer scale defect was made at close proximity to one of the tips of the paper using a pin. Preconcentration of the sample was accomplished by allowing a 10 μL droplet of an aqueous solution of the analyte to stand at the defect followed by drying naturally. The dried paper was used as the substrate for paper spray mass spectrometry by eluting the analyte with a suitable solvent. This novel technique was used to detect melamine in adulterated milk, whose detection at the ppt level in milk normally needs sophisticated instruments, a larger amount of sample, and a complex sampling procedure, including further purification and separation. The SHPPSI MS detects melamine directly from milk at the sub-ppb level by simply putting a microdroplet of adulterated milk at the substrate and eluting the sample with methanol. This paper-based technique can be a promising tool for direct sensing of analytes such as drugs in body fluids, pesticides in water and soil, etc.
- Published
- 2019
19. Caffeine consumption and sleep in a submarine environment: An observational study.
- Author
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Chabal S, Folstein JR, Chinoy ED, Markwald RR, and Lieberman HR
- Subjects
- Humans, Sleep, Sleep Deprivation, Wakefulness, Caffeine pharmacology, Sleep Initiation and Maintenance Disorders
- Abstract
Submariners face many environmental and operational challenges to maintaining good sleep, including suboptimal lighting, shift work, and frequent interruptions. Anecdotally, many Sailors consume caffeine to alleviate the effects of poor sleep on alertness, mood, and performance; however, caffeine itself may also degrade sleep quantity and/or quality. This study provides the first exploration of the potential relationship between caffeine use and sleep onboard submarines. Objective measures (wrist actigraphy, available from 45 participants), self-report sleep metrics, and self-reported caffeine consumption were collected from 58 US Navy Sailors before and during a routine submarine underway at sea lasting 30 days. Contrary to expectations, less caffeine was reportedly consumed at sea (232.8 ± 241.1 mg) than on land prior to the underway (M = 284.4 ± 251.7 mg; X
2 (1) = 7.43, p = 0.006), positive rather than negative relationships were observed between caffeine consumption and sleep efficiency (F = 6.11, p = 0.02), and negative relationships were observed between caffeine consumption and wake after sleep onset (F = 9.36, p = 0.004) and sleep fragmentation (F = 24.73, p < 0.0001). However, in contrast, higher caffeine consumption was also negatively related to self-reported sleep duration while at sea (F = 4.73, p = 0.03). This observational study is the first to measure relationships between caffeine consumption and sleep quantity and/or quality in a submarine environment. We propose that the unique submarine environment and the unique caffeine consumption patterns of submariners should be considered in the development of potential countermeasures for sleepiness., (Published 2023. This article is a U.S. Government work and is in the public domain in the USA. Journal of Sleep Research published by John Wiley & Sons Ltd on behalf of European Sleep Research Society.)- Published
- 2023
- Full Text
- View/download PDF
20. Methods paper: Performance characteristics of novel assays for circulating levels of proglucagon-derived peptides and validation in a placebo controlled cross-over randomized clinical trial
- Author
-
Nikolaos Perakakis, Bhanu Kalra, Angeliki M. Angelidi, Ajay Kumar, Anna Gavrieli, Mary Yannakoulia, and Christos S. Mantzoros
- Subjects
Endocrinology ,C-Peptide ,Glucagon-Like Peptide 1 ,Oxyntomodulin ,Endocrinology, Diabetes and Metabolism ,Caffeine ,Glicentin ,Humans ,Water ,Glucagon ,Peptides ,Proglucagon ,Coffee - Abstract
The measurement of proglucagon-derived peptides (PGDPs) is a challenging task mainly due to major overlaps in their molecular sequence in addition to their low circulating levels. Here, we present the technical characteristics of novel ELISA assays measuring C-peptide and all six PGDPs including, for the first time, major proglucagon fragment (MPGF), and we validate them by performing a pilot in vivo cross-over randomized clinical trial on whether coffee consumption may affect levels of circulating PGDPs.The performance and technical characteristics of novel ELISA assays from Ansh measuring GLP-1, GLP-2, oxyntomodulin, glicentin, glucagon, MPGF and C-peptide were first evaluated in vitro in procured samples from a commercial vendor as well as in deidentified human samples from three previously performed clinical studies. Their performance was further evaluated in vivo in the context of a cross-over randomized controlled trial, in which 33 subjects consumed in random order and together with a standardized meal, 200 ml of either (a) instant coffee with 3 mg/kg caffeine, or (b) instant coffee with 6 mg/kg caffeine, (c) or water.All assays demonstrated high accuracy (spike and recovery and average linearity recovery ±15%), precision (inter-assay CV ≤ 6.4%), specificity (no significant cross-reactivities) and they were sensitive in low concentrations. Measurements of glicentin in archived random human samples using the Ansh assay correlated strongly with the glicentin measurements of Mercodia assay (r = 0.968) and of GLP-1 modestly with Millipore GLP-1 assay (r = 0.440). Oxyntomodulin, glicentin and glucagon concentrations were 2-5 fold higher in plasma compared to serum and serum concentrations correlated modestly (for oxyntomodulin and glicentin) or poorly (for glucagon) with the plasma concentrations. The evaluated assays detected a postprandial increase of gut-secreted PGDPs (GLP-1, GLP-2, oxyntomodulin and glicentin) and a postprandial decrease of pancreas-secreted PGDPs (glucagon, MPGF) in response to consuming coffee in comparison to consuming water with breakfast (enter here composition of breakfast). Only coffee consumption at the high dose alter levels of gut-secreted PGDPs and both at low and high dose to lower levels of pancreas-secreted PGDPs compared to water consumption during breakfast.Accurate, precise and specific measurement of six PGDPs is possible with novel assays. A randomized controlled trial demonstrated in vivo utility of those assays and supports the notion that coffee may exert part of its beneficial effects on glucose homeostasis in the short term through the regulation of PGDPs.
- Published
- 2021
21. Introducing mass spectrometry to first-year undergraduates: Analysis of caffeine and other components in energy drinks using paper-spray mass spectrometry.
- Author
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Sneha, Mahima, Dulay, Maria T., and Zare, Richard N.
- Subjects
- *
ENERGY drinks , *CAFFEINE , *MASS spectrometry , *FILTER paper , *UNDERGRADUATES - Abstract
We describe the use of ambient ionization mass spectrometry in a freshman-level undergraduate class for the detection of caffeine and other components in several commercially available energy drinks (5-hour Energy, Starbucks Refreshers, Red Bull Sugarfree, and Coca Cola Classic). We use the technique of paper-spray mass spectrometry where a filter paper is used as a substrate on which a sample is directly applied and a high voltage is used to generate an electrospray of ions in ambient conditions which are then detected by a mass spectrometer. The purpose of this laboratory exercise is twofold: 1) to use the paper-spray method to determine the chemical composition of different types of commercially available energy drinks and 2) to perform tandem mass spectrometry (MS/MS) to demonstrate that the mass spectrometer can be used for structural analysis. This laboratory serves as an excellent means of introducing the beginning student to the concepts of charge, mass, and molecular structure. In addition to the freshmen general chemistry class, we also incorporated this lab into the introductory analytical chemistry class taught at the sophomore level with the inclusion of a third exercise where the usefulness of mass spectrometry for quantitative analysis is demonstrated by determining the concentration of caffeine in the energy drinks with deuterated caffeine as an internal standard. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
22. A rapid method for the assay of methylxanthines alkaloids: Theobromine, theophylline and caffeine, in cocoa products and drugs by paper spray tandem mass spectrometry
- Author
-
Carlo Siciliano, Lucia Bartella, Fabio Mazzotti, Giovanni Sindona, Anna Napoli, and Leonardo Di Donna
- Subjects
Analyte ,Mass spectrometry ,Tandem mass spectrometry ,01 natural sciences ,Analytical Chemistry ,0404 agricultural biotechnology ,Theophylline ,Limit of Detection ,Tandem Mass Spectrometry ,Caffeine ,medicine ,Theobromine ,Chromatography, High Pressure Liquid ,Detection limit ,Cacao ,Reproducibility ,Chromatography ,Chemistry ,010401 analytical chemistry ,Selected reaction monitoring ,Reproducibility of Results ,04 agricultural and veterinary sciences ,General Medicine ,040401 food science ,0104 chemical sciences ,Pharmaceutical Preparations ,Food Analysis ,Food Science ,medicine.drug - Abstract
A fast method for the determination of methylxanthines in cocoa products and drugs based on PS-MS/MS under MRM condition has been developed. Analyte ions were generated by applying a high voltage on a paper substrate drenched of sample extract using a small volume (∼15 μL) of spray solvent. The gas phase chemistry of the molecules under investigation has been elucidated. The accuracy values of the methodology ranged from 95 to 110%, while the analytical parameters LOQ, LOD, recovery and reproducibility, calculated analyzing spiked samples, confirmed the consistency of the proposed method. Furthermore, real samples have been analyzed both by the developed methodology and by using a classical HPLC-UV approach obtaining comparable values.
- Published
- 2019
23. European Heart Rhythm Association (EHRA)/European Association of Cardiovascular Prevention and Rehabilitation (EACPR) position paper on how to prevent atrial fibrillation endorsed by the Heart Rhythm Society (HRS) and Asia Pacific Heart Rhythm Society (APHRS)
- Author
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Isabelle C. Van Gelder, Harry J.G.M. Crijns, Chern En Chiang, Pompilio Faggiano, Timm Dickfeld, Martin Halle, Irina Savelieva, Prashanthan Sanders, Ugo Corrà, Emelia J. Benjamin, Gulmira Kudaiberdieva, Jean-Paul Schmid, Massimo F Piepoli, Ana Abreu, Martin K. Stiles, Lale Tokgozoglu, Laurent Fauchier, David R. Van Wagoner, Marc A. Vos, Bulent Gorenek, Deirdre A. Lane, Maja-Lisa Løchen, Francisco Marín, Richard I. Fogel, Márcio Jansen de Oliveira Figueiredo, Gregory Y.H. Lip, Giuseppe Boriani, Josef Niebauer, Stefan Agewall, Andreas Goette, Pedro Marques-Vidal, Torben Larsen, Antonio Pelliccia, Kristen K. Patton, Cardiovascular Centre (CVC), MUMC+: MA Cardiologie (9), RS: CARIM - R2.01 - Clinical atrial fibrillation, Cardiologie, and Kardiyoloji
- Subjects
Epidemiology ,COMMUNITY-BASED COHORT ,Medications ,Comorbidity ,Disease ,Arrhythmias ,Amiodarone ,Indirect costs ,0302 clinical medicine ,OBSTRUCTIVE SLEEP-APNEA ,Air pollution ,Alcohol ,Atrial fibrillation ,Caffeine ,Diabetes ,Diet ,Genetic predisposition ,Health economics ,Hyperlipidaemia ,Hypertension ,Hyperthyroidism ,Obesity ,Obstructive sleep apnoea ,Patient preferences ,Physical activity ,Post-operative atrial fibrillation ,Prevention ,Psychological distress ,Recreational drugs ,Risk factors ,Smoking ,Stroke ,Supraventricular arrhythmias ,Therapy ,Cardiology and Cardiovascular Medicine ,ACUTE ISCHEMIC-STROKE ,education.field_of_study ,Evidence-Based Medicine ,Preventive Health Services / standards ,Prognosis ,NORMAL THYROID-FUNCTION ,medicine.medical_specialty ,RANDOMIZED CONTROLLED-TRIALS ,TYPE-2 DIABETES-MELLITUS ,Risk Assessment ,Article ,03 medical and health sciences ,Quality of life (healthcare) ,Physiology (medical) ,Humans ,Risk factor ,education ,Intensive care medicine ,Life Style ,Atrial Fibrillation / prevention & control ,RISK STRATIFICATION SCHEMES ,Genetic predisposition, Hyperthyroidism, Supraventricular arrhythmias, Post-operative atrial fibrillation, Therapy, Stroke ,Odds ratio ,medicine.disease ,Arrhythmias, Atrial fibrillation, Prevention, Risk factors, Obesity, Hyperlipidaemia, Diet, Caffeine, Alcohol ,Blood pressure ,Relative risk ,Cardiovascular System & Cardiology ,Preventive Medicine ,Risk Reduction Behavior ,030204 cardiovascular system & hematology ,HSM CAR ,Risk Factors ,POLYUNSATURATED-FATTY-ACIDS ,Atrial Fibrillation ,Preventive Health Services ,030212 general & internal medicine ,PARTICULATE AIR-POLLUTION ,Patient preferences, Health economics, Medications ,Atrial Fibrillation / epidemiology ,Treatment Outcome ,Cardiology ,Risk assessment ,EHRA Position Paper ,Cardiology / standards ,medicine.drug ,Consensus ,Population ,Diabetes mellitus ,Internal medicine ,medicine ,Journal Article ,Genetic Predisposition to Disease ,business.industry ,Preventive Medicine / standards ,Obstructive sleep apnoea, Diabetes, Hypertension, Smoking, Air pollution, Recreational drugs, Psychological distress, Physical activity ,Atrial Fibrillation / diagnosis ,BODY-MASS INDEX ,Heart failure ,business ,HEALTH TECHNOLOGY-ASSESSMENT - Abstract
Atrial fibrillation (AF) is an important and highly prevalent arrhythmia, which is associated with significantly increased morbidity and mortality, including a four- to five-fold increased risk for stroke,1,2 a two-fold increased risk for dementia,3,4 a three-fold risk for heart failure,2 a two-fold increased risk for myocardial infarction,5,6 and a 40–90% increased risk for overall mortality.2,7 The constantly increasing number of AF patients and recognition of increased morbidity, mortality, impaired quality of life, safety issues, and side effects of rhythm control strategies with antiarrhythmic drugs, and high healthcare costs associated with AF have spurred numerous investigations to develop more effective treatments for AF and its complications.8 Although AF treatment has been studied extensively, AF prevention has received relatively little attention, while it has paramount importance in the prevention of morbidity and mortality, and complications associated with arrhythmia and its treatment. Current evidence shows a clear association between the presence of modifiable risk factors and the risk of developing AF. By implementing AF risk reduction strategies aiming at risk factors such as obesity, hypertension, diabetes, and obstructive sleep ap-noea (OSA), which are interrelated, we impact upon the escalating incidence of AF in the population and ultimately decrease the healthcare burden of associated co-morbidities of AF. To address this issue, a Task Force was convened by the European Heart Rhythm Association and the European Association of Cardiovascular Prevention and Rehabilitation, endorsed by the Heart Rhythm Society and Asia-Pacific Heart Rhythm Society, with the remit to comprehensively review the published evidence available, to publish a joint consensus document on the prevention of AF, and to provide up-to-date consensus recommendations for use in clinical practice. In this document, our aim is to summarize the current evidence on the association of each modifiable risk factor with AF and the available data on the impact of possible interventions directed at these factors in preventing or reducing the burden of AF. While the evidence on AF prevention is still emerging, the topic is not fully covered in current guidelines and some aspects are still controversial. Therefore, there is a need to provide expert recommendations for professionals participating in the care of at-risk patients and populations, with respect to addressing risk factors and lifestyle modifications. Health economic considerations Atrial fibrillation is a costly disease, both in terms of direct, and indirect costs, the former being reported by cost of illness studies as per-patient annual costs in the range of US $2000–14200 in North America and of €450–3000 in Europe.9 In individuals with AF or at risk of developing AF, any effective preventive measure, intervention on modifiable risk factors or comorbidities, as well as any effective pharmacological or non-pharmacological treatment has the aim to reduce AF occurrence, thromboembolic events and stroke, morbidity and, possibly, mortality related to this arrhythmia. Apart from the clinical endpoints, achievement of these goals has economic significance, in terms of positive impact on direct and indirect costs and favourable cost–effectiveness at mid- or long-term, in the perspective of healthcare systems.10–12 In view of the epidemiological profile of AF and progressive aging of the population,13 an impressive increase of patients at risk of AF or affected by AF,14 also in an asymptomatic stage, is expected in the next decades, inducing a growing financial burden on healthcare systems, not only in Europe and North America, but also worldwide.15,16 In consideration of this emerging epidemiological threat due to AF, it is worth considering a paradigm shift, going beyond the conventional approach of primary prevention based on treatment of AF risk factors, but, instead, considering the potential for ‘primordial’ prevention, defined as prevention of the development of risk factors predisposing to AF in the first place.17 This approach, aimed at avoiding the emergence and penetration of risk factors into the population, has been proposed in general terms for the prevention of cardiovascular diseases17 and should imply combined efforts of policymakers, regulatory and social service agencies, providers, physicians, community leaders, and consumers, in an attempt to improve social and environmental conditions, as well as individual behaviours, in the pursuit of adopting healthy lifestyle choices.16 Since a substantial proportion of incident AF events can be attributable to elevated or borderline levels of risk factors for AF,18 this approach could be an effective way to reduce the financial burden linked to AF epidemiology. In terms of individual behaviour and adoption of a ‘healthy lifestyle’, it is worth considering that availability of full healthcare coverage (through health insurance or the healthcare system) may in some cases facilitate the unwanted risk of reducing, at an individual level, the motivation to adopt all the preventive measures that are advisable, in line with the complex concept of ‘moral hazard effect’.19 Patient education and patient empowerment are the correct strategies for avoiding this undesirable effect.
- Published
- 2017
24. The effect of caffeine consumption on attention performance in female students at the faculty of health sciences
- Author
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Kenger, Emre Batuhan, Ozlu, Tugce, Agopyan, Ani, Ergun, Can, Uslu, Aysenur, Dinsel, Berfin, Disli, Dilhan, and Akdeniz, Nezihe
- Published
- 2023
- Full Text
- View/download PDF
25. Medium Light and Medium Roast Paper-Filtered Coffee Increased Antioxidant Capacity in Healthy Volunteers: Results of a Randomized Trial
- Author
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Marcelo Macedo Rogero, Marcela Piedade Monteiro, Cibelem I. Benites, Daniela Tarasoutchi, Carmen G. C. Vinagre, Telma Angelina Faraldo Corrêa, Vera Lúcia Tuda, Luiz Antonio Machado César, Daniela Moura de Oliveira, Elizabeth Aparecida Ferraz da Silva Torres, Bruno Mahler Mioto, and Thaíse Maria Nogueira Mendes
- Subjects
Adult ,Male ,Paper ,Hot Temperature ,Antioxidant ,Oxygen radical absorbance capacity ,Food Handling ,medicine.medical_treatment ,Coffea ,Coffee ,Antioxidants ,Superoxide dismutase ,Lipid peroxidation ,chemistry.chemical_compound ,Chlorogenic acid ,Reference Values ,Caffeine ,medicine ,Humans ,Food science ,chemistry.chemical_classification ,Cross-Over Studies ,biology ,Glutathione peroxidase ,Middle Aged ,Crossover study ,Maillard Reaction ,chemistry ,Biochemistry ,Chemistry (miscellaneous) ,Catalase ,biology.protein ,Female ,Lipid Peroxidation ,Plant Preparations ,Chlorogenic Acid ,Biomarkers ,Filtration ,Food Science - Abstract
We compared the effects of medium light roast (MLR) and medium roast (MR) paper-filtered coffee on antioxidant capacity and lipid peroxidation in healthy volunteers. In a randomized crossover study, 20 volunteers consumed 482 ± 61 ml/day of MLR or MR for four weeks. Plasma total antioxidant status (TAS), oxygen radical absorbance capacity (ORAC), oxidized LDL and 8-epi-prostaglandin F2α, erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activity were measured at baseline and after the interventions. MLR had higher chlorogenic acids—(CGA; 334 mg/150 mL) and less caffeine (231 mg/150 ml) than MR had (210 and 244 mg/150 ml, respectively). MLR also had fewer Maillard reaction products (MRP) than MR had. Compared with baseline, subjects had an increase of 21 and 26 % in TAS, 13 and 13 % in CAT, 52 and 75 % in SOD, and 62 and 49 % in GPx after MLR and MR consumption (P < 0.001), respectively. ORAC increased after MLR (P = 0.004). No significant alteration in lipid peroxidation biomarkers was observed. Both coffees had antioxidant effects. Although MLR contained more CGA, there were similar antioxidant effects between the treatments. MRP may have contributed as an antioxidant. These effects may be important in protecting biological systems and reducing the risk of diseases related to oxidative stress.
- Published
- 2012
26. Why Britain's 2.5 billion paper coffee cups are an eco disaster; With only one in 400 cups recycled, and even those barely 'green', the hunt is on for an alternative
- Subjects
Coffeehouses ,Purines ,Produce industry ,Caffeine ,General interest ,News, opinion and commentary - Abstract
Byline: Jamie Doward Britain gets through 2.5 billion of them every year, and the number is set to increase. But despite a growing clamour for coffee chains to make their [...]
- Published
- 2020
27. Warning about caffeine content must on caffeinated drinks in paper cups
- Subjects
United States. Food and Drug Administration ,Coca-Cola India Private Ltd. ,Beverage industry ,Soft drink industry ,Beverages ,Caffeine ,Fast food restaurants ,Food and beverage industries - Abstract
Byline: Pushkar Oak, Mumbai Caffeinated beverages served in paper cups must carry a warning about the caffeine content. This was stated in a notice issued to McDonald's by the Food [...]
- Published
- 2017
28. Measuring glomerular blood transfer rate in kidney using diffusion-weighted arterial spin labeling.
- Author
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Ahn HS, Jung Y, and Park SH
- Subjects
- Arteries, Humans, Renal Circulation physiology, Spin Labels, Caffeine, Kidney blood supply, Kidney diagnostic imaging, Kidney physiology
- Abstract
Purpose: To propose a two-compartment renal perfusion model for calculating glomerular blood transfer rate ( INLINEMATH ) as a new measure of renal function., Theory: The renal perfusion signal was divided into preglomerular and postglomerular flows according to flow velocity. By analyzing perfusion signals acquired with and without diffusion gradients, we estimated INLINEMATH , the blood transfer rate from the afferent arterioles into the glomerulus., Methods: A multislice multidelay diffusion-weighted arterial spin labeling sequence was applied to subjects with no history of renal dysfunctions. In the multiple b-value experiment, images were acquired with seven b-values to validate the bi-exponential decays of the renal perfusion signal and to determine the appropriate b-value for suppressing preglomerular flow. In the caffeine challenge, six subjects were scanned twice on the caffeine day and the control day. The INLINEMATH values of the two dates were compared., Results: The perfusion signal showed a bi-exponential decay with b-values. There was no significant difference in renal blood flow and arterial transit time between caffeine and control days. In contrast, cortical INLINEMATH ). These results were consistent with those from the literature., Conclusion: We showed that the perfusion signal consists of two compartments of preglomerular flow and postglomerular flow. The proposed diffusion-weighted arterial spin labeling could measure the glomerular blood transfer rate ( INLINEMATH ), which was sensitive enough to noninvasively monitor the caffeine-induced vasodilation of afferent arterioles., (© 2022 International Society for Magnetic Resonance in Medicine.)
- Published
- 2022
- Full Text
- View/download PDF
29. Physiocognitive Modeling: Explaining the Effects of Caffeine on Fatigue.
- Author
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Halverson T, Myers CW, Gearhart JM, Linakis MW, and Gunzelmann G
- Subjects
- Humans, Psychomotor Performance physiology, Fatigue psychology, Oxygen pharmacology, Pharmaceutical Preparations, Caffeine pharmacology, Sleep Deprivation psychology
- Abstract
Most computational theories of cognition lack a representation of physiology. Understanding the cognitive effects of compounds present in the environment is important for explaining and predicting changes in cognition and behavior given exposure to toxins, pharmaceuticals, or the deprivation of critical compounds like oxygen. This research integrates physiologically based pharmacokinetic (PBPK) model predictions of caffeine concentrations in blood and tissues with ACT-R's fatigue module to predict the effects of caffeine on fatigue. Mapping between the PBPK model parameters and ACT-R model parameters is informed by the neurophysiological literature and established associations between ACT-R modules and brain regions. The results from three such parameter mappings are explored to explain observed data from sleep-deprived participants performing the psychomotor vigilance test with and without caffeine. Predicted caffeine concentrations in the brain are used to modulate procedural parameters in the fatigue module to explain caffeine's effects on multiple performance metrics., (© 2022 Cognitive Science Society. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.)
- Published
- 2022
- Full Text
- View/download PDF
30. Fast analysis of caffeine in beverages and drugs by paper spray tandem mass spectrometry
- Author
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Domenico Taverna, Leonardo Di Donna, Fabio Mazzotti, Lucia Bartella, Giovanni Sindona, and Anna Napoli
- Subjects
Detection limit ,Chromatography ,Chemistry ,010401 analytical chemistry ,Selected reaction monitoring ,Analytical chemistry ,Reference Standards ,010402 general chemistry ,Mass spectrometry ,Tandem mass spectrometry ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,Analytical Chemistry ,Beverages ,chemistry.chemical_compound ,Pharmaceutical Preparations ,Limit of Detection ,Tandem Mass Spectrometry ,Caffeine ,Quantitative assay ,Spectrophotometry, Ultraviolet ,Reference standards - Abstract
A simple and fast method based on paper spray mass spectrometry for the determination of caffeine in commercial beverages and drugs has been developed; the analyses were carried out in MRM mode, monitoring the transitions m/z 195 → m/z 138 for caffeine and m/z 198 → m/z 140 for the labeled internal standard. To verify the reliability of the proposed approach, a spiked sample (soda drink and paracetamol tablet) with a known amount of caffeine has been prepared and analyzed by PS-MS, providing accuracy values about 100 %; the LOQ and LOD values were calculated at 1.2 and 1.6 μg/mL, respectively. Both beverages and drugs were also analyzed with the classic analytical method based on LC-UV measurements, showing consistent results between the two approaches, thus confirming the reliability of the developed ambient MS determination. Graphical Abstract The assay of caffeine by paper mass spectrometry.
- Published
- 2016
31. Optimization by uniform design U 8 (8 3 ) approach for enhanced caffeine degradation in synthetic wastewater in bioreactor.
- Author
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Shanmugam MK and Gummadi SN
- Subjects
- Biomass, Bioreactors, Coffee, Caffeine, Wastewater analysis
- Abstract
Coffee wastewater contains large amounts of caffeine which affects microflora and seed development to great extent. Although several physio-chemical methods available for caffeine degradation, they are not preferred for large-scale treatment. In this study, we optimized induced cell concentration, aeration and agitation rate for maximizing caffeine degradation rate in bioreactor using Uniform design. Maximum caffeine degradation rate of 23·59 mg L
-1 h-1 was achieved. The reduction in chemical oxygen demand, biological oxygen demand and total organic carbon removal were found to be 72, 78 and 72% respectively. Mathematical model was developed through regression analysis and predicted maximum caffeine degradation rate of 24·2 mg L-1 h-1 under optimal conditions of 0·35 g L-1 biomass, 395 rev min-1 and 1·62 vvm. Experimental validation at optimum condition resulted in 22 mg L-1 h-1 of caffeine degradation rate. This is the first-ever bioreactor study showing highest caffeine degradation rate in synthetic coffee wastewater with limited experimental runs., (© 2022 The Society for Applied Microbiology.)- Published
- 2022
- Full Text
- View/download PDF
32. [Effect of caffeine on the content of the components of the adenyl system and on the activity of p32 incorporation into the myocardium of rats during early periods of their growth].
- Author
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Viktorov AP
- Subjects
- Adenosine Diphosphate analysis, Adenosine Diphosphate metabolism, Adenosine Monophosphate analysis, Adenosine Monophosphate metabolism, Adenosine Triphosphate analysis, Adenosine Triphosphate metabolism, Aging, Animals, Caffeine administration & dosage, Colorimetry, Electrophoresis, Paper, Injections, Intraperitoneal, Myocardium analysis, Phosphorus analysis, Phosphorus metabolism, Phosphorus Radioisotopes, Rats, Spectrophotometry, Adenine Nucleotides metabolism, Caffeine pharmacology, Myocardium metabolism
- Abstract
Caffeine sodium benzoate was injected intraperitoneally at one time in doses of 1 and 50 mg/100 g to rates aged 30 days and 3--5 months. The ATP, ADP, AMP, inorganic phosphorus levels and the p32 incorporation activity were determined in the myocardium. Introduction of the drug in a dose of 1 mg/100 g is shown not to produce any substantial shifts on the level of the study indices in 7-day old and adult animals and to increase the ATP content in 30-day old rattlings. Administration of caffeine in a dose of 50 mg/100 g brings down the ATP content in the myocardium of the animals in all the age categories. As regards the degree of the ATP level changes the 7-day old rattlings are more resistant than are the adult animals.
- Published
- 1976
33. Enzymatic synthesis of chlorogenic acid from caffeoyl coenzyme A and quinic acid.
- Author
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Stöckigt J and Zenk MH
- Subjects
- Carbon Radioisotopes, Cells, Cultured, Chromatography, Paper, Cinnamates, Coenzyme A Ligases metabolism, Mass Spectrometry, Naphthalenes, Plant Growth Regulators, Plants, Toxic, Nicotiana enzymology, Caffeine metabolism, Chlorogenic Acid biosynthesis, Coenzyme A metabolism, Plants enzymology, Quinic Acid metabolism
- Published
- 1974
- Full Text
- View/download PDF
34. Formation of guanine ribonucleotidyl-(3'-5')-adenosine in a flavinogenic strain of Eremothecium ashbyii.
- Author
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Mitsuda H, Nishikawa Y, and Nakajima K
- Subjects
- Chemical Phenomena, Chemistry, Chromatography, Ion Exchange, Chromatography, Paper, Culture Media, Dinucleoside Phosphates, Guanine Nucleotides analysis, Phosphoric Diester Hydrolases, Ribonucleases, Saccharomycetales drug effects, Saccharomycetales growth & development, Adenosine analogs & derivatives, Ascomycota metabolism, Caffeine pharmacology, Guanine Nucleotides biosynthesis, Riboflavin biosynthesis, Saccharomycetales metabolism
- Abstract
The addition of caffeine caused the accumulation of a new nucleotide compound simultaneously with the rigid inhibition of ribofalvin production in non-growing cells of Eremothecium ashbyii. In the present study we tried to identify the structure of the nucleotide compound using non-growing cells of the mold. 1) It became possible to obtain a large amount of mycelia by masscultivation in a reagent tank. 2) A new nucleotide compound, referred to as compound A in the paper, was extracted with perchloric acid solution and purified by the following subsequent procedures: 1) Dowex 1 x 2 (HCOO-) column, 2) charcoal treatment, 3) DEAE-Sephadex A25 (CI-) column, 4) Dowex 1 x 2 (C1-) column, and 5) DEAE-Sephadex A25 (HCO3-) column. 3) The structure of the new nucleotide compound was proved to be guanine ribonucleotidyl-(3'-5')-adenosine (GpA) from the results of the following analyses: 1) alkaline degradation, 2) UV-spectra, IR-spectra and NMR-spectra, and 3) enzymatic treatments with RNase T2 and phosphodiesterase. 4) The roles of caffeine and guanine ribonucleotidyl-(3'-5')-adenosine in connection with flavinogenesis of this mold were discussed.
- Published
- 1976
- Full Text
- View/download PDF
35. [Determination of caffeine and its metabolites in urine].
- Author
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Schmidt G and Schoyerer R
- Subjects
- Chromatography, Paper, Humans, Spectrophotometry, Ultraviolet Rays, Caffeine urine, Theobromine urine, Xanthines urine
- Published
- 1966
36. Caffeine-sensitive repair of ultraviolet light-damaged DNA of mouse L cells.
- Author
-
Fujiwara Y and Kondo T
- Subjects
- Animals, Carbon Isotopes, Centrifugation, Density Gradient, Chromatography, Paper, DNA radiation effects, DNA Repair drug effects, Floxuridine pharmacology, HeLa Cells drug effects, HeLa Cells growth & development, HeLa Cells metabolism, HeLa Cells radiation effects, L Cells drug effects, L Cells growth & development, L Cells radiation effects, Mice, Radiation Effects, Thymidine metabolism, Tritium, Ultraviolet Rays, Caffeine pharmacology, DNA biosynthesis, L Cells metabolism
- Published
- 1972
- Full Text
- View/download PDF
37. [Determination of Theobromine and its metabolites in urine].
- Author
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Schmidt G and Heunisch E
- Subjects
- Chromatography, Paper, Food Contamination, Humans, Spectrophotometry, Caffeine urine, Theobromine urine, Theophylline urine, Xanthines urine
- Published
- 1966
38. Tissue distribution of caffeine and its metabolites in the mouse.
- Author
-
Burg AW and Werner E
- Subjects
- Animals, Brain metabolism, Caffeine blood, Carbon Isotopes, Chromatography, Ion Exchange, Chromatography, Paper, Erythrocytes metabolism, Half-Life, Kinetics, Liver metabolism, Lung metabolism, Male, Methylation, Mice, Mice, Inbred Strains, Muscles metabolism, Myocardium metabolism, Nucleotides biosynthesis, Spleen metabolism, Testis metabolism, Tritium, Uric Acid biosynthesis, Xanthines biosynthesis, Caffeine metabolism
- Published
- 1972
- Full Text
- View/download PDF
39. Urinary excretion of caffeine and its metabolites in the mouse.
- Author
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Burg AW and Stein ME
- Subjects
- Animals, Caffeine metabolism, Caffeine pharmacology, Carbon Dioxide biosynthesis, Carbon Isotopes, Chromatography, Ion Exchange, Chromatography, Paper, Feces analysis, Humans, Kinetics, Male, Methylation, Mice, Mice, Inbred Strains, Tritium, Water biosynthesis, Caffeine urine, Uric Acid urine, Xanthines urine
- Published
- 1972
- Full Text
- View/download PDF
40. [Determination of theophylline, caffeine and ephedrine hydrochloride in the preparation Belladrinal tablet].
- Author
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Reszko-Turska W and Walicka T
- Subjects
- Chlorides, Chromatography, Paper, Colorimetry, Methods, Potentiometry, Tablets, Caffeine analysis, Ephedrine analysis, Theophylline analysis
- Published
- 1968
41. Room-temperature phosphorimetry of methylxanthine stimulants on zeolite-modified filter paper substrates
- Author
-
A. Rupérez, L.M. Cabalín, and J. Javier Laserna
- Subjects
Detection limit ,Analyte ,Chromatography ,Filter paper ,Biochemistry ,Analytical Chemistry ,chemistry.chemical_compound ,chemistry ,medicine ,Theophylline ,Phosphorescence ,Caffeine ,Zeolite ,Theobromine ,medicine.drug ,Nuclear chemistry - Abstract
The phosphorescence characteristics at room temperature of methylxanthine stimulants (caffeine, theophylline and theobromine) on several filter paper substrates (Whatman #1, Whatman DE-81 and Albet) modified with a cation-exchange zeolite have been studied. The zeolite was incorporated into the paper matrix by immersion and stirring of the filter paper in a zeolite aqueous suspension. The effect of zeolite on the phosphorescence decay of the drugs has been studied. Compared to the untreated filter papers, the zeolite-modified paper substrate shows lower background signal and enhanced analyte phosphorescence. As a result, improved limits of detection are found under optimum experimental conditions.
- Published
- 1993
42. Energy Drinks: A Contemporary Issues Paper.
- Author
-
Higgins, John P., Babu, Kavita, Deuster, Patricia A., and Shearer, Jane
- Subjects
ENERGY drinks ,SLEEP apnea syndromes ,ANXIETY ,ATHLETES ,ATHLETIC ability ,CAFFEINE ,EXERCISE - Abstract
Since their introduction in 1987, energy drinks have become increasingly popular and the energy drink market has grown at record pace into a multibillion-dollar global industry. Young people, students, office workers, athletes, weekend warriors, and service members frequently consume energy drinks. Both health care providers and consumers must recognize the difference between energy drinks, traditional beverages (e.g., coffee, tea, soft drinks/sodas, juices, or flavored water), and sports drinks. The research about energy drinks safety and efficacy is often contradictory, given the disparate protocols and types of products consumed: this makes it difficult to draw firm conclusions. Also, much of the available literature is industry-sponsored. After reports of adverse events associated with energy drink consumption, concerns including trouble sleeping, anxiety, cardiovascular events, seizures, and even death, have been raised about their safety. This article will focus on energy drinks, their ingredients, side effects associated with their consumption, and suggested recommendations, which call for education, regulatory actions, changes in marketing, and additional research. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
43. European Heart Rhythm Association (EHRA)/European Association of Cardiovascular Prevention and Rehabilitation (EACPR) position paper on how to prevent atrial fibrillation endorsed by the Heart Rhythm Society (HRS) and Asia Pacific Heart Rhythm Society (APHRS)
- Author
-
Gorenek Chair, Bulent, Pelliccia Co-Chair, Antonio, Benjamin, Emelia J, Boriani, Giuseppe, Crijns, Harry J, Fogel, Richard I, Van Gelder, Isabelle C, Halle, Martin, Kudaiberdieva, Gulmira, Lane, Deirdre A, Bjerregaard Larsen, Torben, Lip, Gregory Y H, Løchen, Maja-Lisa, Marin, Francisco, Niebauer, Josef, Sanders, Prashanthan, Tokgozoglu, Lale, Vos, Marc A, Van Wagoner, David R, Fauchier, Laurent, Savelieva, Irina, Goette, Andreas, Agewall, Stefan, Chiang, Chern-En, Figueiredo, Márcio, Stiles, Martin, Dickfeld, Timm, Patton, Kristen, Piepoli, Massimo, Corra, Ugo, Manuel Marques-Vidal, Pedro, Faggiano, Pompilio, Schmid, Jean-Paul, Abreu, Ana, and Document reviewers
- Subjects
Air pollution ,Medications ,Psychological distress ,Supraventricular arrhythmias ,Arrhythmias ,Post-operative atrial fibrillation ,Hyperthyroidism ,Caffeine ,Recreational drugs ,Journal Article ,Obesity ,Physical activity ,Prevention ,Genetic predisposition ,Diabetes ,Smoking ,Obstructive sleep apnoea, Diabetes, Hypertension, Smoking, Air pollution, Recreational drugs, Psychological distress, Physical activity ,Genetic predisposition, Hyperthyroidism, Supraventricular arrhythmias, Post-operative atrial fibrillation, Therapy, Stroke ,Patient preferences ,Patient preferences, Health economics, Medications ,Arrhythmias, Atrial fibrillation, Prevention, Risk factors, Obesity, Hyperlipidaemia, Diet, Caffeine, Alcohol ,Atrial fibrillation ,Diet ,Stroke ,Risk factors ,Hyperlipidaemia ,Obstructive sleep apnoea ,Hypertension ,Therapy ,Alcohol ,Health economics - Published
- 2017
44. Association of coffee, green tea, and caffeine with the risk of dementia in older Japanese people.
- Author
-
Matsushita N, Nakanishi Y, Watanabe Y, Kitamura K, Kabasawa K, Takahashi A, Saito T, Kobayashi R, Takachi R, Oshiki R, Tsugane S, Iki M, Sasaki A, Yamazaki O, Watanabe K, and Nakamura K
- Subjects
- Adult, Aged, Beverages adverse effects, Cohort Studies, Dementia etiology, Diet Surveys, Female, Follow-Up Studies, Humans, Independent Living statistics & numerical data, Japan epidemiology, Male, Middle Aged, Proportional Hazards Models, Surveys and Questionnaires, Beverages statistics & numerical data, Caffeine, Coffee, Dementia epidemiology, Tea
- Abstract
Objectives: Coffee, green tea, and caffeine are potential preventive factors for dementia, but the underlying evidence is insufficient. This study aimed to examine associations between the consumption of coffee, green tea, and caffeine and dementia risk in middle-aged and older people., Methods: This was a cohort study with an 8.0-year follow-up. Participants were community-dwelling individuals (n = 13,757) aged 40-74 years. A self-administered questionnaire survey was conducted in 2011-2013. Predictors were the consumption of coffee/green tea, from which caffeine consumption was estimated. The outcome was incident dementia obtained from the long-term care insurance database. Covariates were demographic factors, body mass index, physical activity, energy, smoking, drinking, and disease history. Adjusted hazard ratios (HRs) were calculated using Cox proportional hazards models. HRs were also calculated using a Cox model with delayed entry., Results: The number of dementia cases during the study period was 309. Participants with higher coffee consumption had lower HRs (adjusted p for trend = 0.0014), with the fifth quintile (≥326 ml/day) having a significantly lower HR (0.49, 95% confidence interval [CI]: 0.30-0.79) than the first quintile (<26 ml/day, reference). Similarly, participants with higher caffeine consumption had a significantly lower HR (adjusted p for trend = 0.0004) than the reference. The Cox model with delayed entry yielded similar results. These associations were significant in men, but not in women. Moreover, participants who consumed 2-2.9 cups/day and ≥3 cups/day of coffee had lower HRs (0.69, 95% CI: 0.48-0.98 and 0.53, 95% CI: 0.31-0.89, respectively) than those who consumed 0 cup/day. The association between green tea consumption and reduced dementia risk was significant (adjusted p for trend = 0.0146) only in the 60-69 years age subgroup., Conclusions: High levels of coffee and caffeine consumption were significantly associated with a reduced dementia risk in a dose-dependent manner, especially in men. Moreover, coffee consumption of ≥3 cups/day was associated with a 50% reduction in dementia risk., (© 2021 The American Geriatrics Society.)
- Published
- 2021
- Full Text
- View/download PDF
45. Transdermal Permeation of Caffeine Aided by Ionic Liquids: Potential for Enhanced Treatment of Cellulitis.
- Author
-
Hernandes AN, Boscariol R, Balcão VM, and Vila MMDC
- Subjects
- Administration, Cutaneous, Adult, Caffeine pharmacokinetics, Cosmetics, Double-Blind Method, Drug Compounding, Drug Stability, Female, Gels, Humans, Ionic Liquids, Middle Aged, Pilot Projects, Skin Absorption, Caffeine administration & dosage, Caffeine therapeutic use, Lipodystrophy drug therapy
- Abstract
Ginoid hydrolipodystrophy (HDLG) or "cellulite" involves alteration of the cutaneous relief and occurs in 80-90% of the female population. Several topical treatments are available with the use of substances capable of stimulating lipolysis, such as caffeine. However, the effectiveness of topical therapy is related to the processes of release and permeation of the active in skin cells. In this sense, ionic liquids, such as choline geranate, are considered to facilitate topical permeation agents. In this way, the aim of this research was to develop and evaluation of the effectiveness of a cosmetic product for topical treatment of cellulite with caffeine in association with choline geranate. The choline geranate was synthesized by the reaction between geranic acid and choline hydroxide [1: 2]. The gel was prepared using 2% Carpobol 940®, 5% caffeine, and 1% choline geranate. Preliminary and accelerated stability tests were performed by checking pH, spreadability, and organoleptic characteristics. The transdermal permeation capacity of caffeine in vitro was evaluated by the Franz cell permeation assay, and the gel cytotoxicity by the MTS method. To prove the efficacy in the treatment of cellulite, a pilot type 1 clinical trial was carried out. The formulation was considered stable and the product maintained your characteristics during 180 days of storage. The product showed moderate cytotoxicity and high skin permeation capacity. In the clinical trial, it showed results superior to the caffeine gel without ionic liquid. The developed gel favored the cutaneous permeation of caffeine, showing a promising product in the treatment of cellulite.
- Published
- 2021
- Full Text
- View/download PDF
46. μOPTO: A microfluidic paper-based optoelectronic tongue as presumptive tests for the discrimination of alkaloid drugs for forensic purposes.
- Author
-
Dias, Bárbara Cristina, Batista, Alex D., and da Silveira Petruci, João Flávio
- Subjects
- *
ATROPINE , *TROPANES , *TONGUE , *ALKALOIDS , *CAFFEINE , *MICROFLUIDIC devices , *SCOPOLAMINE - Abstract
Natural and synthetic alkaloids are widely used for several applications, ranging from clinical purposes to criminal activities. Presumptive color tests are considered a leading tool to reveal on-scene substance identification via rapid chemical reactions that result in visual color changes. Colorimetric tests are popular due to their inherent simplicity, low cost, promptitude and portability; however, in many cases the results of such tests may not be predictable, partly because of the interference from similar species. In this proof-of-concept study, we present a paper-based microfluidic optoelectronic tongue – the so-called μOPTO – comprised of 6 indicators in lieu of one specific test and capable of discriminating 8 different alkaloid drugs (i.e. scopolamine, atropine, cocaine, morphine, ephedrine, caffeine, dipyrone and alprazolam) used for recreational, criminal and medical purposes. The wax printing method was employed to fabricate the microfluidic analytical device with six circular spots for reagent accommodation connected to a centered spot to enable simultaneous reactions with one sample injection. Digital images were obtained using an ordinary flatbed scanner, and the RGB information from before and after sample exposure was extracted using appropriate software. The color changes related to each spot were used to build differential maps with a unique fingerprint for each drug. The chemometric tools (i.e. PCA and HCA) showed suitable discrimination of all studied alkaloids in different quantities. To demonstrate a practical application, different alcoholic beverages spiked with scopolamine – a famous substance that causes drug abuse – were analyzed using the optoelectronic tongue. The results showed that small quantities of the drug were identified in different beverages, demonstrating that our device has the potential to be used in situ to prevent ingestion of contaminated samples. [Display omitted] • A microfluidic paper-based optoelectronic tongue for the discrimination of eight alkaloids is presented. • The array was comprised of 6 chemoresponsive reagents. • The color change after reaction enabled the creation of a unique fingerprint for each alkaloid. • Chemometric tools allowed useful discrimination of the drugs. • The μOPTO was applied to identify contaminated alcoholic beverages. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
47. What do we really know about the role of caffeine on urinary tract symptoms? A scoping review on caffeine consumption and lower urinary tract symptoms in adults.
- Author
-
Le Berre M, Presse N, Morin M, Larouche M, Campeau L, Hu YX, Reid I, and Dumoulin C
- Subjects
- Adult, Humans, Caffeine, Lower Urinary Tract Symptoms physiopathology
- Abstract
Aims: The purpose of this scoping review was to map out the existing literature on caffeine intake and lower urinary tract symptoms (LUTS) in adults., Methods: In this scoping review, we searched for all studies available until June 2019 in MEDLINE, Embase, CINAHL, Cochrane Central Register, PsycINFO, LILACS, LiSSa, Web of Science, and Joanna Briggs Institute electronic databases, in addition to a hand search of the bibliographies of all relevant articles and a gray literature search. Both intervention studies on the effects of caffeine reduction in adults with LUTS and observational studies on the association between caffeine intake and LUTS-related outcomes in adults were included and assessed for methodological quality by two independent reviewers., Results: Fourteen intervention and 12 observational studies were included. Overall, there was a decrease in urgency episodes (level of evidence 2, grade of recommendation B) and nocturnal enuresis episodes (4, C) with caffeine reduction. Observational studies reported an unclear association between caffeine intake and LUTS-related outcomes. Most importantly, this present review highlighted high heterogeneity in the studied populations, caffeine measures, and reported outcomes. There was also unknown or high risk of bias in most identified studies., Conclusions: Caffeine reduction appears to reduce LUTS. Future studies on caffeine reduction interventions should target populations with urgency and urge urinary incontinence, which show the most promising results, and include valid and reliable measures of caffeine intake and LUTS. Finally, future studies should also use reporting guidelines to ensure lower risk of bias., (© 2020 Wiley Periodicals, Inc.)
- Published
- 2020
- Full Text
- View/download PDF
48. Percutaneous absorption between frog species: Variability in skin may influence delivery of therapeutics.
- Author
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Llewelyn VK, Berger L, and Glass BD
- Subjects
- Animals, Anti-Inflammatory Agents, Non-Steroidal administration & dosage, Anti-Inflammatory Agents, Non-Steroidal chemistry, Anti-Inflammatory Agents, Non-Steroidal pharmacokinetics, Antifungal Agents administration & dosage, Antifungal Agents chemistry, Antifungal Agents pharmacokinetics, Benzoic Acid administration & dosage, Benzoic Acid chemistry, Caffeine administration & dosage, Caffeine chemistry, Central Nervous System Stimulants administration & dosage, Central Nervous System Stimulants chemistry, Central Nervous System Stimulants pharmacokinetics, Ibuprofen administration & dosage, Ibuprofen chemistry, Permeability, Skin Absorption, Species Specificity, Anura, Benzoic Acid pharmacokinetics, Caffeine pharmacokinetics, Ibuprofen pharmacokinetics, Skin
- Abstract
Frogs have permeable skin, so transdermal delivery provides a practical alternative to traditional dosing routes. However, little is known about how frog skin permeability differs interspecifically, and there are different reported clinical outcomes following topical application of the same chemical in different frog species. This study collated in vitro absorption kinetic data previously reported for two frog species: the green tree frog (Litoria caerulea) and the cane toad (Rhinella marina), and used linear mixed-effects modelling to produce a model of absorption. Histology of skin samples from each species was performed to observe morphological differences that may affect absorption. Absorption kinetics differed significantly between species, with the logP of the applied chemical a better predictor of permeability than molecular weight. Application site also influenced permeability, with dorsal permeability consistently higher in cane toads. Ventral permeability was more consistent between species. Skin thickness differed between species and skin regions, and this may explain the differences in absorption kinetics. Guidelines for selecting chemicals and dosing site when treating frogs are presented. The permeability differences identified may explain the poor reproducibility reported in the treatment of disease across frog species, and reinforces the importance of considering interspecies differences when designing therapeutic treatments for frogs., (© 2019 John Wiley & Sons Ltd.)
- Published
- 2020
- Full Text
- View/download PDF
49. Thin layer chromatography coupled to paper spray ionization mass spectrometry for cocaine and its adulterants analysis.
- Author
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De Carvalho, Thays C., Tosato, Flavia, Souza, Lindamara M., Santos, Heloa, Merlo, Bianca B., Ortiz, Rafael S., Rodrigues, Rayza R.T., Filgueiras, Paulo R., França, Hildegardo S., Augusti, Rodinei, Romão, Wanderson, and Vaz, Boniek G.
- Subjects
- *
ELECTROSPRAY ionization mass spectrometry , *COCAINE abuse , *THIN layer chromatography , *CRIME laboratories , *BENZOCAINE , *AMIDES , *CAFFEINE , *COCAINE , *COMPARATIVE studies , *DRUG adulteration , *LIDOCAINE , *MASS spectrometry , *RESEARCH methodology , *MEDICAL cooperation , *NARCOTICS , *RESEARCH , *EVALUATION research - Abstract
Thin layer chromatography (TLC) is a simple and inexpensive type of chromatography that is extensively used in forensic laboratories for drugs of abuse analysis. In this work, TLC is optimized to analyze cocaine and its adulterants (caffeine, benzocaine, lidocaine and phenacetin) in which the sensitivity (visual determination of LOD from 0.5 to 14mgmL(-1)) and the selectivity (from the study of three different eluents: CHCl3:CH3OH:HCOOHglacial (75:20:5v%), (C2H5)2O:CHCl3 (50:50v%) and CH3OH:NH4OH (100:1.5v%)) were evaluated. Aiming to improve these figures of merit, the TLC spots were identified and quantified (linearity with R(2)>0.98) by the paper spray ionization mass spectrometry (PS-MS), reaching now lower LOD values (>1.0μgmL(-1)). The method developed in this work open up perspective of enhancing the reliability of traditional and routine TLC analysis employed in the criminal expertise units. Higher sensitivity, selectivity and rapidity can be provided in forensic reports, besides the possibility of quantitative analysis. Due to the great simplicity, the PS(+)-MS technique can also be coupled directly to other separation techniques such as the paper chromatography and can still be used in analyses of LSD blotter, documents and synthetic drugs. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
50. Adsorption behaviors of (–)-epigallocatechin gallate and caffeine on macroporous adsorption resins functionalized with carbazole and N-methylimidazole
- Author
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Liu, Yongfeng, Liu, Yi, and Di, Duolong
- Published
- 2020
- Full Text
- View/download PDF
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