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A one-pot method for the simple, efficient, and environmentally benign protocol for the synthesis of Spiro-Indoline/Indene derivatives containing Aza indole moiety as a side chain is outlined. The 1,3-dipolar cycloaddition reaction of azomethine ylides derived from ethynyl Azaindole under mild conditions is accomplished. The low cost, easy availability of the starting material, and simple reaction conditions suggest the possible use of the present method for large-scale preparations. [ABSTRACT FROM AUTHOR]

Abstract: Sarcosine is a potential prostate cancer marker. In this study, we developed a method of three‐phase solvent bar liquid‐phase microextraction combined with high‐performance liquid chromatography to determine sarcosine after derivatization with 4‐dimethylarminoazobenzene‐4‐sulfonyl chloride from human urine. The effects of different extraction conditions on extraction efficiency were investigated and optimized. Under optimum experimental conditions, a calibration graph exhibited linearity over the range of 0.05–25 μmol/L with a correlation coefficient (r2) of 0.9990. The enrichment factor was 168, and the detection limit was 0.02 μmol/L. The method was successfully used to analyze sarcosine in human urine and non‐invasive detection, and good spiked recoveries ranging from 90.5 to 93.6% were obtained. The proposed method exhibited high sensitivity, high enrichment factor, good precision, and a simple setup. It may contribute to the early accurate diagnosis and the progression monitoring of prostatic carcinoma. [ABSTRACT FROM AUTHOR]

Amino acids are emerging as alternative solvents for absorption-based CO 2 capture, but their potential to form the harmful byproducts nitrosamines is not well understood. This study investigated the formation of nitrosamines from model amino acids sarcosine, proline, and taurine under desorber- and absorber-relevant conditions. Special attention was paid to the effects of base and the formation of volatile nitrosamines. Under simulated desorber conditions, all three amino acid solvents with organic base monoethanolamine (MEA) formed more total nitrosamines than those with inorganic base sodium hydroxide (NaOH). Increasing base concentration decreased the formation of N -nitrososarcosine (NSAR) in both NaOH- and MEA-based sarcosine solvents. By measuring NSAR formation under varying base concentration and CO 2 loading, it was shown that both sarcosine carbamic acid (SARCOOH) and deprotonated sarcosine (SAR − ) contributed to NSAR formation. Volatile nitrosamine N -nitrosodimethylamine (NDMA) was detected in sarcosine solvents at levels three orders of magnitude lower than NSAR. Kinetic modeling showed that 61%–110% of the accumulated NDMA was formed through NSAR decomposition. NDMA formation from NSAR was promoted by increasing MEA concentration, but suppressed by increasing NaOH concentration. Under simulated absorber conditions, NaOH- and MEA-based solvents formed total nitrosamines at similar rates for sarcosine, proline, and taurine. In sarcosine solvents, NDMA formed at levels three orders of magnitude lower than NSAR, similar to that under desorber conditions. [ABSTRACT FROM AUTHOR]

The most worldwide used herbicide is glyphosate, phosphonomethylglycine (PMG). Consequently, a significant amount of PMG, its metabolites (sarcosine, SAR, and aminomethylphosphonic acid, AMPA) and the degradation product, methylphosphonic acid (MPA), reaches the soil, which acts as final sink. Because clays are one of the most reactive components of soils, expansive clays such as montmorillonite (Mt) are used to retain agriculture contaminants with some success. In this work, as a preliminary step for the evaluation of the risk that PMG, SAR, AMPA, and MPA occurrence could have on the environment, their adsorption on Mt surface was performed. The adsorption process was analyzed at constant adsorbate concentrations and two pH values to take into account the different protonation states of the amino group. DTA, XRD, zeta potential measurements, and XPS were used to identify the interactions or association mechanisms with the clay surface, the entry of adsorbates into the Mt interlayer, and electric charge changes on the Mt surface, and evaluate the acid-base surface complex constants, respectively. The interlayer thickness in acid media indicated that adsorbates are able to enter the interlayer in planar form. Besides, for the Mt-PMG sample, some PMG molecules could be also inserted as a bilayer or with a tilt angle of 52.4° in the interlayer. However, in alkaline media, the interlayer thickness indicated that the adsorbate arrangement differed from that of acidic media where PMG and MPA could have more than one orientation. The surface complex deprotonation constants were determined for the =NH+2 ⇆ =NH+H+ process, being 3.0, 5.0, and 7.3 for PMG, AMPA, and SAR, respectively. [ABSTRACT FROM AUTHOR]

An amperometric sarcosine biosensor was fabricated based on covalent immobilization of sarcosine oxidase (SarOx) onto the nanocomposite of carboxylated multi-walled carbon nanotubes (cMWCNT)/chitosan (CHIT) and copper nanoparticles (CuNPs), electrodeposited on gold (Au) electrode. The SarOx/CHIT/CuNPs/c-MWCNT/Au electrode was characterized by scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The enzyme electrode exhibited optimum current within 2 s at a potential of 0.2 V against Ag/AgCl, pH 7.0 and 35 °C. A linear relationship was obtained between sarcosine concentration in the range, 0.1–100 μM and current (mA) under optimum conditions. The biosensor exhibited a high sensitivity of 277.5 μA/μM/cm 2 , a low detection limit of 0.1 pM and excellent storage stability (180 days). The analytical recoveries of added sarcosine in sera at 0.5 μM and at 1.0 μM concentration were 95.5% and 97.30 respectively. The precision i.e. within and between-batch coefficients of variation (CVs) were 1.08% and 1.70% respectively. There was a good correlation (R 2  = 0.99) between the level of sarcosine in sera as measured by the standard immuno kit method and the present biosensor. The biosensor measured sarcosine level in sera of prostate cancer patients, which was significantly higher than those of apparently healthy persons (p value <0.01). [ABSTRACT FROM AUTHOR]

We report on synthesis, structural and vibrational spectroscopic characterization of the (SarH) 6 [F 5 Al-F-AlF 5 ]F ( I ) salt. The compound ( I ) is the first salt of amino acids with a dimeric undecafluoridodialuminate [F 5 Al-F-AlF 5 ] 5− anion and the first mixed salt of sarcosine with different anions. It crystallizes in orthorhombic system, space group Pbca . The simulated FT-IR spectrum for a cluster which comprises 13 cations, [F 5 Al-F-AlF 5 ] 5− anion and a fluoride anions built from the crystal structure is compared with the experimental spectrum and agree reasonably well. [ABSTRACT FROM AUTHOR]

Layer-by-layer composite films of carbon nanotubes (CNTs) within a chitosan matrix with sarcosine oxidase enzyme and capped with Nafion have been developed and optimized as a versatile 1st generation amperometric sarcosine biosensing platform that operates successfully both as an isolated sarcosine sensor as well as a functional component within a creatinine sensor. Accurate measurement of sarcosine in urine and creatinine in blood may help with early diagnosis of diseases such as prostate cancer and renal failure, respectively. In this study, each material within the film is systematically optimized toward sarcosine sensitivity, including a critical evaluation of different CNTs effect on sensing performance. Films featuring carboxylic acid–modified single–walled carbon nanotubes and strategic enzyme doping were shown to be most effective sarcosine sensing platforms, exhibiting excellent sensitivity (~0.5 μA/mM), a linear response (≤0.75 mM), fast response time (8 s), low limits of detection (~6 μM), as well as both continuous use stability (7 days) and effective shelf life (>12 days). Operation of the sarcosine sensor was demonstrated in a sarcosine-spiked urine matrix, detecting the analyte at physiologically relevant concentrations (≥20 μM) and successfully quantifying sarcosine-spiked urine samples at 20, 40, and 90 μM ( n  = 9, 7, and 3) with high average percent recoveries (>98%) and low relative error. The sarcosine sensing platform was also adapted to a 1st generation creatinine biosensing scheme in which the sarcosine enzymatic reaction is critical to a tri-enzymatic cascade event. The creatinine sensor yielded sensitivity of ~0.6 μA/mM, similar sensing performance parameters to the sarcosine sensor, and was effectively operated in blood serum at physiologically relevant creatinine concentrations (>1 mM). The demonstrated functionality of these sensors in their respective biological fluids at physiological concentrations of the analyte species suggests potential clinical application as diagnostic tools. [ABSTRACT FROM AUTHOR]

Due to their central role in biochemical processes, fast separation and identification of amino acids (AA) is of importance in many areas of the biomedical field including the diagnosis and monitoring of inborn errors of metabolism and biomarker discovery. Due to the large number of AA together with their isomers and isobars, common methods of AA analysis are tedious and time-consuming because they include a chromatographic separation step requiring pre- or post-column derivatization. Here, we propose a rapid method of separation and identification of sarcosine, a biomarker candidate of prostate cancer, from isomers using differential ion mobility spectrometry (DIMS) interfaced with a tandem mass spectrometer (MS/MS) instrument. Baseline separation of protonated sarcosine from α- and β-alanine isomers can be easily achieved. Identification of DIMS peak is performed using an isomer-specific activation mode where DIMS- and mass-selected ions are irradiated at selected wavenumbers allowing for the specific fragmentation via an infrared multiple photon dissociation (IRMPD) process. Two orthogonal methods to MS/MS are thus added, where the MS/MS(IRMPD) is nothing but an isomer-specific multiple reaction monitoring (MRM) method. The identification relies on the comparison of DIMS-MS/MS(IRMPD) chromatograms recorded at different wavenumbers. Based on the comparison of IR spectra of the three isomers, it is shown that specific depletion of the two protonated α- and β-alanine can be achieved, thus allowing for clear identification of the sarcosine peak. It is also demonstrated that DIMS-MS/MS(IRMPD) spectra in the carboxylic C=O stretching region allow for the resolution of overlapping DIMS peaks.ᅟ [ABSTRACT FROM AUTHOR]

Abstract: Objective: Augmentation of sarcosine, a natural inhibitor of the glycine transporter type I, normalizes glutamatergic neurotransmission, having beneficial impact on primary negative symptoms in schizophrenia and may also influence immune system and interleukin 6 (IL‐6) levels. Aim: Finding a relationship between initial IL‐6 serum concentrations or its changes and severity of symptoms as a result of sarcosine addition to stable antipsychotic treatment. Method: Fifity‐eight individuals with schizophrenia with predominantly negative symptoms completed a 6‐month randomized, double‐blind placebo‐controlled prospective study. Patients received 2 g of sarcosine (n = 29) or placebo (n = 30) daily per os. We measured IL‐6 levels and severity of symptoms at the beginning, after 6 weeks and 6 months. As main clinical tools, we used Positive and Negative Syndrome Scale (PANSS) and Calgary depression scale for schizophrenia (CDSS). Results: Augmentation with sarcosine had no effect on IL‐6 serum levels in all time points. We noted significant improvements in negative symptoms, general psychopathology, and total PANSS score in the sarcosine group. We found correlation of initial serum IL‐6 with severity of positive symptoms and negative association between IL‐6 levels reduction and positive symptoms reduction. Conclusions: Sarcosine does not significantly affect IL‐6 concentrations but IL‐6 may be involved in mechanisms related to the presence of positive symptoms. [ABSTRACT FROM AUTHOR]

Shortly after sarcosine was delineated as a potential biomarker for prostate cancer in 2009, a variety of analytical methods for clinical application were developed. Moreover, higher uptake of glycine in the mitochondria also played a role in cancer proliferation. A major constraint in the accurate quantification of sarcosine was the interference of the two isomers, a-alanine and ß-alanine, using chromatographic separation techniques. Accordingly, we aimed to develop an analytical method for determining sarcosine and its related metabolites (a- and ß-alanine, glycine and creatinine) under the same conditions by gas chromatography-tandem mass spectrometry (GCMS/MS). BSTFA + 1% TMCS was used for silylation, and GC-MS/MS conditions were optimized for the target analytes. The unique transition ions of sarcosine, a- and ß-alanine, glycine and creatinine set up in MRM acquisition were m/z 116 → 73, 190 → 147, 176 → 147, 176 → 147 and 100 → 73, respectively. This newly developed method was successfully validated to apply in clinical settings with low limits of detection (0.01 - 0.03 µg•mL-1), high correlations (R2 > 0.99), great accuracy (88 - 110% recovery), and notable precision (RSD < 10%). All TMS derivatives were > 80% stable for up to 2 h after derivatization and analyzing during this period promises to achieve an accurate result. Monitoring the five-substance profile could enhance prospects for early diagnosis of prostate cancer. [ABSTRACT FROM AUTHOR]

An enzyme-coupled colorimetric assay for quantification of urinary sarcosine was developed. The proposed method is a specific reaction based on hydrogen peroxide (H2O2) formation via sarcosine oxidase (SOX). The liberated H2O2 reacts with Amplex Red in the presence of horseradish peroxidase (HRP) to produce the redfluorescent oxidation product, resorufin, which can be measured spectrophotometrically (OD570). The method was performed in the 96-well microtiter plate. Reaction conditions, such as pH and reaction time were optimized. At the optimum conditions, the limit of detection (LOD) and quantification (LOQ) were found to be 0.7 and 1 µM, respectively. A good linearity was revealed with a coefficient of 0.990. The assay showed no significant interference from ascorbic acid, glucose and bilirubin. In addition, it is extremely specific for sarcosine rather than other amino acids. The determination of sarcosine in human urine displayed high accuracy and good reproducibility. This method is promising to differentiate prostate cancer patients from healthy subjects according to urinary sarcosine level. Altogether, this study provides a rapid, simple and specific tool to determine urinary sarcosine which could be useful for prostate cancer diagnosis. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Fe 3 O 4 @SiO 2 @NiCo 2 S 4 has both superior oxidase activity and peroxidase activity. • The Fe 3 O 4 @SiO 2 @NiCo 2 S 4 has good recyclability. • Fe 3 O 4 @SiO 2 @NiCo 2 S 4 can be employed to the detection of ascorbic acid and sarcosine. • A sensitive, simple and specific colorimetric detection tool has been designed. In this paper, Fe 3 O 4 @SiO 2 @NiCo 2 S 4 nanocomposite catalytic materials were prepared using a low eutectic solvent and hydrothermal method. Characterization was performed using scanning electron microscopy, transmission electron micrographs, X-ray photoelectron spectra, X-ray diffraction, Zeta potential and Fourier transform infrared spectrometry, and Vibrating sample magnetometry. The catalytic mechanism was verified by Electron Paramagnetic Resonance experiments. Several assay platforms were established based on their different enzyme activities. Based on the oxidase-like activity, a colorimetric sensing assay for ascorbic acid was developed with a linear range and detection limit of 1–200 µM and 0.36 µM, respectively. Sarcosine can be effectively quantified by utilizing its peroxidase-like activity. The linear range of sarcosine assay was 1.25–350 µM with a detection limit of 0.42 µM. Notably, Fe 3 O 4 @SiO 2 @NiCo 2 S 4 exhibited reusability and high precision in quantifying sarcosine in human urine samples. The nanomaterials could be easily and quickly separated from the reaction system using a magnet for future use due to their superior magnetic properties. Therefore, the colorimetric sensing analytical method established in this study provided a new strategy for the detection of ascorbic acid in food matrices and serum samples as well as sarcosine in urine samples. The developed method also provided a potential application of composite and bimetallic materials in the fields of food detection, bioanalysis, and clinical disease diagnosis. [ABSTRACT FROM AUTHOR]

Glyphosate-based herbicides (GBH) use has increased drastically over the last decade. This is true especially for potato crops due to their fast harvest cycle and high market demand. In 2015, the World Health Organization (WHO) classified glyphosate and its breakdown product amidomethylphosphonic acid (AMPA) as probably carcinogenic to humans, and it has been reported that these compounds disrupt the ecological and nutritional equilibrium of soils. However, microorganisms with the sarcosine oxidase gene, such as Lysinibacillus sphaericus, can degrade glyphosate through the Carbon-Phosphorus (C-P) pathway without leading to AMPA production. The aim of this study was to evaluate the addition of the plant growth-promoting bacteria (PGPB) L. sphaericus as a bioremediation agent in a potato crop sprayed with a GBH, in conjunction with the nitrogen fixation activity mediated by the bacteria. To that end, a GBH solution was used to treat a potato field, and different treatments (glyphosate (G), bacteria (B), bacteria+glyphosate (BG), and negative control (C)) were evaluated by measuring the glyphosate, AMPA, nitrates, and ammonium concentrations. BG treatment showed a 79% reduction of glyphosate concentration in soil, leading to minimal AMPA production, compared to the 23% reduction observed after G treatment. Furthermore, the ammonium concentrations were significantly higher in samples treated with BG and in C samples (p < 0.005). Therefore, we propose the addition of L. sphaericus as a good bioremediation strategy for soils sprayed with GBH.

For the first time, arylmethylidene cyclohexanones that are non-symmetrical due to the presence of peripheral substituents were studied in 1,3-dipolar cycloaddition reactions. It is shown that the interaction with the azomethine ylide generated from sarcosine proceeds regio- and diastereoselectively, with the participation of two non-equivalent parts of the dipolarophile. Also for the first time, β-amino ketones (Mannich bases) were used as dipolarophile equivalents of unsaturated ketones. It was found that cycloaddition occurs diastereoselectively at the generated center. [ABSTRACT FROM AUTHOR]

This work investigated the preparation of chitosan nanoparticles used as carriers for doxorubicin for targeted cancer delivery. Prepared nanocarriers were stabilized and functionalized via zinc ions incorporated into the chitosan nanoparticle backbone. We took the advantage of high expression of sarcosine in the prostate cancer cells. The prostate cancer targeting was mediated by the AntiSar antibodies decorated surface of the nanocage. Formation of the chitosan nanoparticles was determined using a ninhydrin assay and differential pulse voltammetry. Obtained results showed the strong effect of tripolyphosphine on the nanoparticle formation. The zinc ions affected strong chitosan backbone coiling both in inner and outer chitosan nanoparticle structure. Zinc electrochemical signal depended on the level of the complex formation and the potential shift from -960 to -950 mV. Formed complex is suitable for doxorubicin delivery. It was observed the 20% entrapment efficiency of doxorubicin and strong dependence of drug release after 120 min in the blood environment. The functionality of the designed nanotransporter was proven. The purposed determination showed linear dependence in the concentration range of Anti-sarcosine IgG labeled gold nanoparticles from 0 to 1000 μg/mL and the regression equation was found to be y = 3.8x - 66.7 and R2 = 0.99. Performed ELISA confirmed the ability of Anti-sarcosine IgG labeled chitosan nanoparticles with loaded doxorubicin to bind to the sarcosine molecule. Observed hemolytic activity of the nanotransporter was 40%. Inhibition activity of our proposed nanotransporter was evaluated to be 0% on the experimental model of S. cerevisiae. Anti-sarcosine IgG labeled chitosan nanoparticles, with loaded doxorubicin stabilized by Zn ions, are a perspective type of nanocarrier for targeted drug therapy managed by specific interaction with sarcosine and metallothionein for prostate cancer. [ABSTRACT FROM AUTHOR]

Alcohol-initiated ring-opening polymerization (ROP) of cyclic esters for synthesizing polyesters was well established, but amine-initiated ROP of cyclic esters was rare. A challenge is slow initiation and fast propagation in the amine-initiated ROPs. To address the difficulties, an ionic H-bond donor (iHBD) and H-bond acceptor (HBA) binary organocatalysis in amine-initiated ROP of lactide (LA) was developed. Guanidinium hexahydro-2 H -pyrimido[1,2- a ] pyrimidin-1-ium [(HppH 2 ) + ] and tertiary amine sparteine (SP), cooperatively played the role of iHBD/HBA binary catalysts, efficiently promoted ROP of LA from amine initiators toward polylactide (PLA) and polysarcosine- block -polylactide diblock copolymer (PSar- b -PLA). Benzyl amine and N -methylbenzylamine initiated ROPs of LA under mild conditions produced PLAs with predictable molecular weights ( M n,NMR  = 2.9–17.1 kg mol −1 ) and narrow dispersities ( Ð M,SEC  = 1.13–1.23). Macroinitiator PSar copolymerized with LA under the iHBD/HBA catalysis, producing PSar- b -PLAs with controlled molecular weights ( M n,NMR  = 5.7–14.8 kg mol −1 ) and low dispersities ( Ð M,SEC  = 1.16–1.21). Kinetics and chain extension experiments confirmed that the amine-initiated ROP of LA in presence of (HppH 2 ) + BF 4 − /SP was in controlled/living manner. 1 H NMR, 13 C NMR, SEC, and MALDI-ToF MS analyses indicated that the obtained PLA was exclusively initiated from the corresponding amine with amide linkage. An iHBD/HBA binary activation mechanism was proposed. [ABSTRACT FROM AUTHOR]

Background: Left atrial appendage (LAA) closure (LAAC) by implantation of an occlusion device is an established cardiac intervention to reduce risk of stroke while avoiding intake of oral anticoagulation medication during atrial fibrillation. Cardiac interventions can alter local or systemic gene and protein expression. Effects of LAAC on systemic metabolism have not been studied yet. Objectives: We aimed to study the effects of interventional LAAC on systemic metabolism. Methods: Products of glycolysis, tricarboxylic acid and urea metabolism were analyzed by ESI-LC-MS/MS and MS/MS using the AbsoluteIDQ™ p180 Kit in plasma of 44 patients undergoing successful interventional LAAC at baseline (T0) and after 6 months (T1). Results: During follow up, plasma concentrations of several parameters of glycolysis and tricarboxylic acid cycle (TCA) and urea metabolism increased (alanine, hexose, proline, sarcosine), while others decreased (aspartate, glycine, SDMA, serine). Multivariate linear regression analysis showed that time after interventional LAAC was an independent predictor for metabolite changes, including the decrease of SDMA (beta −0.19, p < 0.01) and the increase of sarcosine (beta 0.16, p < 0.01). Conclusions: Successful interventional LAAC affects different pathways of the metabolome, which are probably related to cardiac remodeling. The underlying mechanisms as well as the long term effects have to be studied in the future. [ABSTRACT FROM AUTHOR]

In this work, physical properties such as density, refractive index and viscosity of aqueous diethanolamine sarcosinate (DEA-SAR) solution were measured at different temperatures. The knowledge of physical properties is necessary for the process design and simulation of acid gas absorber plant. Various concentrations of aqueous DEA-SAR solutions (0.05, 0.10, 0.15, 0.20, 0.25 and 0.30) were investigated at temperature ranging from 298.15 to 333.15 K. The reported results showed an increment behavior in the physical properties with the increase in concentration isothermally, and a decreasing one with the rise in temperature of the solution at any given concentration. Empirical models were applied to correlate the experimental data of each physical property as a function of both concentration and temperature. A quantitative analysis of variation was carried out for estimating the significance of the physical property's data. [ABSTRACT FROM AUTHOR]

Abstract: Microsolvation of neutral and zwitterionic conformations of sarcosine is explored at ωB97XD/6‐311++G(d,p) level. Natural Bond Orbital and Boltzman population results are used to show the importance of the methyl group in sarcosine. Various configurations have been considered to locate the low lying configuration of sarcosine (neutral and zwitterionic forms) with one to four water molecules. The various sarcosine‐(water)1‐4 clusters have been analyzed with the established hydrogen bonding networks. The current findings revealed that one water molecule is enough to stabilize the zwitterionic form of sarcosine. Additionally, the higher number of water molecules interacting with Sarcosine shows that neutral and zwitterionic tautomers of sarcosine attained the isoenergetic with four water molecules. [ABSTRACT FROM AUTHOR]

The use of amino acids as potential solvents for carbon dioxide (CO 2 ) capture has been considered by a number of researchers. However, very little is known about the kinetics and mechanism of amino acids-CO 2 reactions. In this work, we investigate the reactions of three amino acids ( l -Arginine, Glycine and Sarcosine) with CO 2 in aqueous media using stopped-flow conductivity technique. The experiments were performed at temperatures between 293 and 313 K and amino acids concentrations were in the range of 0.05–0.2 molar. The overall rate constants (k ov ) was found to increase with increased amino acid concentration and solution temperature. Both zwitterion and termolecular mechanisms were used to model and interpret the data. However, the Zwitterion mechanism was found to be the preferred one. From the stopped-flow results at pH around 6, we found that neutral l -Arginine, Glycine and Sarcosine react with CO 2 (aq) with k (M −1 s −1 ) = 2.81 × 10 10 exp( − 4482.9 T ( K ) ), k (M −1 s −1 ) = 3.29 × 10 13 exp( − 8143.7 T ( K ) ) and k (M −1 s −1 ) = 3.90 × 10 13 exp( − 7991.0 T ( K ) ) respectively. The corresponding activation energies are 37.28 kJ mol −1 , 67.71 kJ mol −1 And 66.44 kJ mol −1 respectively. A comparison between the kinetics of the three amino acids showed that Arginine exhibits highest reaction rate with CO 2 followed by Sarcosine and then Glycine. The technique and results obtained from this work can be used as strong tools in the development of efficient new solvents for the removal of CO 2 from flue and industrial gases. [ABSTRACT FROM AUTHOR]

Sarcosine is an N-methyl derivative of the amino acid glycine, and its elevation in tissues and physiological fluids of patients with sarcosinemia could reflect a deficient pool size of activated 1-carbon units. Sarcosinemia is a rare inherited metabolic condition associated with mental retardation. In the present study, we investigated the acute effect of sarcosine and/or creatine plus pyruvate on some parameters of oxidative stress and energy metabolism in cerebral cortex homogenates of 21-day-old Wistar rats. Acute administration of sarcosine induced oxidative stress and diminished the activities of adenylate kinase, GAPDH, complex IV, and mitochondrial and cytosolic creatine kinase. On the other hand, succinate dehydrogenase activity was enhanced in cerebral cortex of rats. Moreover, total sulfhydryl content was significantly diminished, while DCFH oxidation, TBARS content, and activities of SOD and GPx were significantly enhanced by acute administration of sarcosine. Co-administration of creatine plus pyruvate was effective in the prevention of alterations provoked by sarcosine administration on the oxidative stress and the enzymes of phosphoryltransfer network. These results indicate that acute administration of sarcosine may stimulate oxidative stress and alter the energy metabolism in cerebral cortex of rats. In case these effects also occur in humans, they may contribute, along with other mechanisms, to the neurological dysfunction of sarcosinemia, and creatine and pyruvate supplementation could be beneficial to the patients. [ABSTRACT FROM AUTHOR]

In this article we report on the development and optimization of a biomimetic sensor for the label-free detection of the amino acid sarcosine, a molecule which is seen as a biomarker for prostate cancer. The recognition elements were sarcosine-imprinted poly-aminothiophenol ( p -ATP) layers deposited by electro-polymerization onto screen-printed gold electrodes and, for comparison, onto carbon electrodes covered first with a gold-nanoparticles interlayer. Using the latter type of electrodes, we reached a detection limit below 1 nM in aqueous buffer solutions with an accessible concentration range from the nano- to the micromolar scale. This was achieved by a careful thickness optimization of the Au-nanoparticle and the p -ATP layers in combination with Faradaic impedance spectroscopy as a readout method. The sensor showed an excellent reproducibility, a good stability with time, and a surprisingly low cross-selectivity towards other proteins. [ABSTRACT FROM AUTHOR]

Objectives: Regular aerobic exercise provides beneficial effects on human health and reduces all-cause mortality. Aerobic exercise has profound metabolic effects, and specific metabolites may reflect physiological changes. We aimed to identify endogenous metabolites that distinguish the trained from the untrained state to increase the spectrum of analytes amenable for hypothesis testing and to expand understanding of putative beneficial pathways.Design: Cross sectional laboratory repeated measures study.Methods: Exercise testing was performed in 37 healthy male participants and serum samples were obtained before and after completion of a ten-week standardized exercise program. Samples were analyzed for routine clinical parameters and for 188 endogenous metabolites by LC-MS/MS.Results: Indicating the effectiveness of the intervention program, parameters of sport physiology were different after training. After correcting for multiple testing, serum concentrations of several metabolites differed between the trained and untrained state. Serine and glutamate decreased in response to exercise, whereas sarcosine and kynurenine increased. Phosphatidylcholines showed a mixed response in that four species increased and three decreased. However, all seven lysophosphatidylcholines and all four plasmalogens that differed between the trained and untrained state, increased. One short-chain acylcarnitine also decreased. In receiver operator characteristics analyses, sarcosine displayed the highest AUC value (0.839; 95% CI: 0.734-0.926) in discriminating the pre- from the post-trained state.Conclusions: Our study detected metabolites that clearly differentiate the trained from the untrained state. These metabolites may be targeted in mechanistic studies to understand underlying biochemical pathways and could serve to improve the design, monitoring and individualization of training programs. [ABSTRACT FROM AUTHOR]