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Hemodialysis International.... Oct 2013This article distinguishes the terms "phosphorus, phosphorous, and phosphate" which are frequently used interchangeably. We point out the difference between phosphorus...
This article distinguishes the terms "phosphorus, phosphorous, and phosphate" which are frequently used interchangeably. We point out the difference between phosphorus and phosphate, with an emphasis on the unit of measure. Expressing a value without the proper name or unit of measure may lead to misunderstanding and erroneous conclusions. We indicate why phosphate must be expressed as milligrams per deciliter or millimoles per liter and not as milliequivalents per liter. Therefore, we elucidate the distinction among the terms "phosphorus, phosphorous, and phosphate" and the importance of saying precisely what one really means.
Topics: Humans; Phosphates; Phosphorus; Renal Dialysis
PubMed: 23279081
DOI: 10.1111/hdi.12010 -
Drug Testing and Analysis Aug 2022New biomarkers indicating the abuse of drugs and alcohol are still of major interest for clinical and forensic sciences. The endogenous neurotransmitter and approved...
New biomarkers indicating the abuse of drugs and alcohol are still of major interest for clinical and forensic sciences. The endogenous neurotransmitter and approved drug, gamma-hydroxybutyric acid (GHB), is often illegally used for drug-facilitated crimes by spiking GHB into alcoholic beverages. Analytical detection windows of only 6 h in blood and 12 h in urine are often too short to provide reliable proof of GHB ingestion. Therefore, new biomarkers are needed to prove exogenous GHB administration. Previously, amino acid GHB conjugates were discovered in an untargeted metabolomics screening and fatty acid esters with GHB were recently discussed as promising biomarkers to enlarge the analytical detection time windows. However, the development of analytical methods is still slowed down since reference compounds for targeted screenings are still missing. In this paper, we describe simple procedures for the rapid synthesis and purification of amino acid GHB conjugates as well as fatty acid esters, which can be adopted in analytical and clinical/forensic laboratories. Structural characterization data, together with IR, H-nuclear magnetic resonance (NMR), C-NMR, high-resolution mass spectra (MS), and MS/MS spectra in positive and negative ionization mode are reported for all obtained GHB conjugates and GHB conjugate precursors.
Topics: Amino Acids; Biomarkers; Hydroxybutyrates; Laboratories; Sodium Oxybate; Tandem Mass Spectrometry
PubMed: 35415886
DOI: 10.1002/dta.3273 -
Diabetes Care Aug 2008The A1C assay, expressed as the percent of hemoglobin that is glycated, measures chronic glycemia and is widely used to judge the adequacy of diabetes treatment and...
OBJECTIVE
The A1C assay, expressed as the percent of hemoglobin that is glycated, measures chronic glycemia and is widely used to judge the adequacy of diabetes treatment and adjust therapy. Day-to-day management is guided by self-monitoring of capillary glucose concentrations (milligrams per deciliter or millimoles per liter). We sought to define the mathematical relationship between A1C and average glucose (AG) levels and determine whether A1C could be expressed and reported as AG in the same units as used in self-monitoring.
RESEARCH DESIGN AND METHODS
A total of 507 subjects, including 268 patients with type 1 diabetes, 159 with type 2 diabetes, and 80 nondiabetic subjects from 10 international centers, was included in the analyses. A1C levels obtained at the end of 3 months and measured in a central laboratory were compared with the AG levels during the previous 3 months. AG was calculated by combining weighted results from at least 2 days of continuous glucose monitoring performed four times, with seven-point daily self-monitoring of capillary (fingerstick) glucose performed at least 3 days per week.
RESULTS
Approximately 2,700 glucose values were obtained by each subject during 3 months. Linear regression analysis between the A1C and AG values provided the tightest correlations (AG(mg/dl) = 28.7 x A1C - 46.7, R(2) = 0.84, P < 0.0001), allowing calculation of an estimated average glucose (eAG) for A1C values. The linear regression equations did not differ significantly across subgroups based on age, sex, diabetes type, race/ethnicity, or smoking status.
CONCLUSIONS
A1C levels can be expressed as eAG for most patients with type 1 and type 2 diabetes.
Topics: Adult; Aged; Blood Glucose; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Male; Middle Aged; Models, Theoretical; Monitoring, Ambulatory; Reference Values; Regression Analysis
PubMed: 18540046
DOI: 10.2337/dc08-0545 -
Annales Pharmaceutiques Francaises May 2022Information available on the packaging of drugs indicated for patients electrolytes replenishment differs from one manufacturer to another. They relate, for example, the...
OBJECTIVES
Information available on the packaging of drugs indicated for patients electrolytes replenishment differs from one manufacturer to another. They relate, for example, the unit chosen to express elemental electrolyte concentration. These differences constitute a risk factor for medication errors. This article proposes a clinical decision support tool which defines dose equivalences between the oral and injectable formulation galenic forms for medications providing phosphorus, calcium and magnesium and a calculated replenishment ratio.
METHODS
The amounts of elemental electrolyte were determined from the information contained on the packaging and the summaries of product characteristics. Only the specialties of our hospital drug formulary were studied. For each element, the replenishment ratio was determined from published data.
RESULTS
Equivalence tables were created for the phosphorus, calcium and magnesium between oral and injectable formulation. A clinical decision support tool was developed from these data.
CONCLUSION
The use of this tool is a first way to reduce the risk of medication errors. It remains to determine the conditions for its dissemination and evaluation. This issue raises the questions of the exclusive use of the millimole unit on packaging and for prescription, and that of the integration of this type of tool into prescription software and decision support systems.
Topics: Calcium; Electrolytes; Humans; Magnesium; Phosphorus; Prescriptions
PubMed: 34153239
DOI: 10.1016/j.pharma.2021.06.001 -
International Journal of Molecular... Dec 2022Astrocytes are the most abundant glial cells in the central nervous system (CNS) mediating a variety of homeostatic functions, such as spatial K buffering or... (Review)
Review
Astrocytes are the most abundant glial cells in the central nervous system (CNS) mediating a variety of homeostatic functions, such as spatial K buffering or neurotransmitter reuptake. In addition, astrocytes are capable of releasing several biologically active substances, including glutamate and GABA. Astrocyte-mediated GABA release has been a matter of debate because the expression level of the main GABA synthesizing enzyme glutamate decarboxylase is quite low in astrocytes, suggesting that low intracellular GABA concentration ([GABA]) might be insufficient to support a non-vesicular GABA release. However, recent studies demonstrated that, at least in some regions of the CNS, [GABA] in astrocytes might reach several millimoles both under physiological and especially pathophysiological conditions, thereby enabling GABA release from astrocytes via GABA-permeable anion channels and/or via GABA transporters operating in reverse mode. In this review, we summarize experimental data supporting both forms of GABA release from astrocytes in health and disease, paying special attention to possible feedback mechanisms that might govern the fine-tuning of astrocytic GABA release and, in turn, the tonic GABA receptor-mediated inhibition in the CNS.
Topics: Astrocytes; gamma-Aminobutyric Acid; Neuroglia; Receptors, GABA-A; Glutamic Acid
PubMed: 36555501
DOI: 10.3390/ijms232415859 -
Angewandte Chemie (International Ed. in... Jul 2020Miniaturization and acceleration of synthetic chemistry is an emerging area in pharmaceutical, agrochemical, and materials research and development. Herein, we describe...
Miniaturization and acceleration of synthetic chemistry is an emerging area in pharmaceutical, agrochemical, and materials research and development. Herein, we describe the synthesis of iminopyrrolidine-2-carboxylic acid derivatives using chiral glutamine, oxo components, and isocyanide building blocks in an unprecedented Ugi-3-component reaction. We used I-DOT, a positive-pressure-based low-volume and non-contact dispensing technology to prepare more than 1000 different derivatives in a fully automated fashion. In general, the reaction is stereoselective, proceeds in good yields, and tolerates a wide variety of functional groups. We exemplify a pipeline of fast and efficient nanomole-scale scouting to millimole-scale synthesis for the discovery of a useful novel reaction with great scope.
Topics: Automation; Crystallography, X-Ray; Drug Discovery; Imines; Miniaturization; Molecular Structure; Nanotechnology; Pyrrolidines
PubMed: 32048418
DOI: 10.1002/anie.202000887 -
Nature Communications Jan 2024Industrial hydrogen peroxide (HO) is synthesized using carbon-intensive H gas production and purification, anthraquinone hydrogenation, and anthrahydroquinone oxidation....
Industrial hydrogen peroxide (HO) is synthesized using carbon-intensive H gas production and purification, anthraquinone hydrogenation, and anthrahydroquinone oxidation. Electrochemical hydrogenation (ECH) of anthraquinones offers a carbon-neutral alternative for generating HO using renewable electricity and water instead of H gas. However, the HO formation rates associated with ECH are too low for commercialization. We report here that a membrane reactor enabled us to electrochemically hydrogenate anthraquinone (0.25 molar) with a current efficiency of 70% at current densities of 100 milliamperes per square centimeter. We also demonstrate continuous HO synthesis from the hydrogenated anthraquinones over the course of 48 h. This study presents a fast rate of electrochemically-driven anthraquinone hydrogenation (1.32 ± 0.14 millimoles per hour normalized per centimeter squared of geometric surface of electrode), and provides a pathway toward carbon-neutral HO synthesis.
PubMed: 38278793
DOI: 10.1038/s41467-024-44741-1 -
Chemical Communications (Cambridge,... Mar 2024High-throughput continuous flow technology has emerged as a revolutionary approach in chemical synthesis, offering accelerated experimentation and improved efficiency.... (Review)
Review
High-throughput continuous flow technology has emerged as a revolutionary approach in chemical synthesis, offering accelerated experimentation and improved efficiency. With the aid of process analytical technology and automation, this system not only enables rapid optimisation of reaction conditions at the millimole to the picomole scale, but also facilitates automated scale-up synthesis. It can even achieve the self-planning and self-synthesis of small drug molecules with artificial intelligence incorporated in the system. The versatility of the system is highlighted by its compatibility with both electrochemistry and photochemistry, and its significant applications in organic synthesis and drug discovery. This highlight summarises its recent developments and applications, emphasising its significant impact on advancing research across multiple disciplines.
PubMed: 38436212
DOI: 10.1039/d3cc06180a -
Rapid Communications in Mass... 2007Three stable isotope ratios, D/H, (13)C/(12)C and (18)O/(16)O, are measurable in ethanol, an important organic compound that is used as a material for food and...
Three stable isotope ratios, D/H, (13)C/(12)C and (18)O/(16)O, are measurable in ethanol, an important organic compound that is used as a material for food and beverages, fuel and chemical feedstock, and as a substance related to metabolism. We developed a simple and rapid method of measurement of three isotope ratios of ethanol in aqueous solution at millimole levels using gas chromatography-high-temperature conversion or combustion-isotope ratio mass spectrometry (GC-TC/C-IRMS) combined with solid-phase microextraction (SPME). Using this method, the delta value for ethanol was determined in 30 min for deltaD and delta(13)C, and in 75 min for delta(18)O with precisions of +/-9 per thousand, +/-0.3 per thousand and +/-0.7 per thousand, respectively, for deltaD, delta(13)C, and delta(18)O. An advantage of this process is that it requires no distillation for ethanol purification. The method is useful for small quantities of analyte with low ethanol concentrations, which is expected for environmental and metabolic studies.
Topics: Carbon Isotopes; Deuterium; Ethanol; Gas Chromatography-Mass Spectrometry; Microchemistry; Oxygen Isotopes
PubMed: 17377934
DOI: 10.1002/rcm.2977