Synthesis of zwitterionic salts of pyridinium-Meldrum acid and barbiturate through unique four-component reactions.

PubMed

Wang, Qi-Fang; Hui, Li; Hou, Hong; Yan, Chao-Guo

2010-03-08

An efficient synthetic procedure for the preparation of the unusual charge-separated pyridinium-Meldrum acid and N,N-dimethylbarbiturate acid zwitterionic salts was developed though a unique one-pot four-component reaction involving pyridine, aromatic aldehyde, Meldrum acid or N,N-dimethylbarbituric acid, and p-nitrobenzyl bromide in acetonitrile. By varying combinations of four components involving nitrogen-containing heterocycles, we conveniently established reactive alpha-halomethylene compounds, aldehydes and beta-dicarbonyl compounds a library of zwitterionic salts.

Medical Readings on Drug Abuse.

ERIC Educational Resources Information Center

Byrd, Oliver E.

Summaries are presented of over 150 articles in the recent medical and psychiatric literature. Topics covered are: effects of drugs, tobacco, alcohol, drugs used in medicine, vapor sniffing, marijuana, barbiturates, tranquilizers, amphetamines, methamphetamine, lysergic acid diethylamide, other hallucinogens, heroin and the opiates, psychiatric…

Barbiturates Bind in the GLIC Ion Channel Pore and Cause Inhibition by Stabilizing a Closed State*♦

PubMed Central

Fourati, Zaineb; Ruza, Reinis Reinholds; Laverty, Duncan; Drège, Emmanuelle; Delarue-Cochin, Sandrine; Joseph, Delphine; Koehl, Patrice; Smart, Trevor; Delarue, Marc

2017-01-01

Barbiturates induce anesthesia by modulating the activity of anionic and cationic pentameric ligand-gated ion channels (pLGICs). Despite more than a century of use in clinical practice, the prototypic binding site for this class of drugs within pLGICs is yet to be described. In this study, we present the first X-ray structures of barbiturates bound to GLIC, a cationic prokaryotic pLGIC with excellent structural homology to other relevant channels sensitive to general anesthetics and, as shown here, to barbiturates, at clinically relevant concentrations. Several derivatives of barbiturates containing anomalous scatterers were synthesized, and these derivatives helped us unambiguously identify a unique barbiturate binding site within the central ion channel pore in a closed conformation. In addition, docking calculations around the observed binding site for all three states of the receptor, including a model of the desensitized state, showed that barbiturates preferentially stabilize the closed state. The identification of this pore binding site sheds light on the mechanism of barbiturate inhibition of cationic pLGICs and allows the rationalization of several structural and functional features previously observed for barbiturates. PMID:27986812

Binding of urea and thiourea with a barbiturate derivative: experimental and theoretical approach.

PubMed

Dixit, Namrata; Shukla, P K; Mishra, P C; Mishra, Lallan; Roesky, Herbert W

2010-01-14

A barbiturate derivative [1,5-dihydro-5-[5-pyrimidine-2,4(1H,3H)-dionyl]-2H-chromeno[2,3-d] pyrimidine-2,4(3H)-dione)] (L1) possesses functionalities complementary to amide and thioamide. Hence its binding with urea and thiourea, is monitored using UV-vis and fluorescence titrations as well as isothermal titration calorimetry (ITC) study. Theoretical studies on hydrogen-bonded complexes of L1-urea and L1-thiourea in the gas phase, aqueous, and DMSO medium are carried out using density functional theory (DFT) at the B3LYP/6-31G** level. The theoretical calculations support the experimental results.

Synthesis of novel heterocycles through reaction of indolin-2-one derivatives with active methylene and amino reagents.

PubMed

Abdel-Latif, F F; Ahmed, E K; Mekheimer, R; Mashaly, M M

1997-10-01

Several new spiro compounds were synthesized via one-pot ternary condensation of isatin, malononitrile and each of thiobarbituric acid, barbituric acid, 3-methyl-pyrazolin-5-one, 1-phenyl-3-methyl-pyrazolin-5-one, acetylacetone, benzoylacetone, ethyl acetoacetate, phenacyl cyanide or ethyl-cyanoacetate dimer. Structures and reaction mechanism were reported and supported via a second synthetic route.

THE EFFECT OF X IRRADIATION AND CYSTEAMINE ON THE BARBITURATE SLEEPING TIME IN RATS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Varagic, V.; Stepanovic, S.; Hajdukovic, S.

Whole-body x irradiation with 600 and 800 r prolongs barbiturate sleeping time in the rat. In the head-irradiated animals (with the same doses) no prolongation of barbiturate sleeping time was observed. Irradintion of the animal with the head shielded produced the same effect as irradiation of the whole body. Cysteamine depressed or even blocked the prolonging action of x irradiation on barbiturate sleeping time. This action of cysteamine was evident 24 hr after irradiation and was still present 30 days after irradiation. The prolonging effect of x irradiation was significant as early as 24 hr after exposure but was moremore » pronounced 14, 21, and 30 days after irradiation. This suggests that even the primary event which takes place immediately after absorption of radiation energy produces a change in reactivity to barbiturates. The results obtained with headirradiated animals indicate that the reactivity of the central nervous system to barbiturates is not significantly changed. Therefore, x irradiation may produce some change in the detoxication process of barbiturates in the liver. Or, some biologically active substance might be released which contributes to the prolongation of the effect of barbiturates. Possibly 5-hydroxytryptamine liberated by x irradiation from intestine might contribute to the prolongation of the barbiturate hypnosis. (H.H.D.)« less

Knoevenagel Reaction of Unprotected Sugars

NASA Astrophysics Data System (ADS)

Scherrmann, Marie-Christine

The Knoevenagel reaction of unprotected sugars was investigated in the 1950s using zinc chloride as promoter. The so-called Garcia Gonzalez reaction had been almost forgotten for 50 years, until the emergence of new water tolerant catalysts having Lewis acid behavior. The reaction was thus reinvestigated and optimal conditions have been found to prepare trihydroxylated furan derivatives from pentose or β-tetrahydrofuranylfuran from hexoses with non-cyclic β-keto ester or β-diketones. Other valuable compounds such as β-linked tetrahydrobenzofuranyl glycosides or hydroxyalkyl-3,3,6,6,-tetramethyl-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione can be obtained using cyclic β-dicarbonylic derivatives. Apart from one report in the 1950s, the Knoevenagel reaction of unprotected carbohydrate in basic condition has been studied only in the mid-1980s to prepare C-glycosyl barbiturates from barbituric acids and, later on, from non-cyclic β-diketones, β-C-glycosidic ketones. The efficient method exploited to prepare such compounds has found an industrial development in cosmetics.

The Effectiveness of the Human Patient Simulator in Teaching Anesthesia Pharmacology to First Year Nurse Anesthesia Students

DTIC Science & Technology

2002-12-01

month period. Simulator scenarios included overdose of inhalation anesthetic, oxygen source failure, cardiac arrest, malignant hypothermia, tension...may most effectively attenuate emergence delirium? a. Propofol b. Versed*** c. Fentanyl d. Droperidol 6. Barbituric acid is formed by the

Trisubstituted barbiturates and thiobarbiturates: Synthesis and biological evaluation as xanthine oxidase inhibitors, antioxidants, antibacterial and anti-proliferative agents.

PubMed

Figueiredo, Joana; Serrano, João L; Cavalheiro, Eunice; Keurulainen, Leena; Yli-Kauhaluoma, Jari; Moreira, Vânia M; Ferreira, Susana; Domingues, Fernanda C; Silvestre, Samuel; Almeida, Paulo

2018-01-01

Barbituric and thiobarbituric acid derivatives have become progressively attractive to medicinal chemists due to their wide range of biological activities. Herein, different series of 1,3,5-trisubstituted barbiturates and thiobarbiturates were prepared in moderate to excellent yields and their activity as xanthine oxidase inhibitors, antioxidants, antibacterial agents and as anti-proliferative compounds was evaluated in vitro. Interesting bioactive barbiturates were found namely, 1,3-dimethyl-5-[1-(2-phenylhydrazinyl)ethylidene]pyrimidine-2,4,6(1H,3H,5H)-trione (6c) and 1,3-dimethyl-5-[1-[2-(4-nitrophenyl)hydrazinyl]ethylidene]pyrimidine-2,4,6(1H,3H,5H)-trione (6e), which showed concomitant xanthine oxidase inhibitory effect (IC 50 values of 24.3 and 27.9 μM, respectively), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (IC 50 values of 18.8 and 23.8 μM, respectively). In addition, 5-[1-(2-phenylhydrazinyl)ethylidene]pyrimidine-2,4,6(1H,3H,5H)-trione (6d) also revealed DPPH radical scavenger effect, with an IC 50 value of 20.4 μM. Moreover, relevant cytotoxicity against MCF-7 cells (IC 50  = 13.3 μM) was observed with 5-[[(2-chloro-4-nitrophenyl)amino]methylene]-2-thioxodihydropyrimidine-4,6(1H,5H)-dione (7d). Finally, different 5-hydrazinylethylidenepyrimidines revealed antibacterial activity against Acinetobacter baumannii (MIC values between 12.5 and 25.0 μM) which paves the way for developing new treatments for infections caused by this Gram-negative coccobacillus bacterium, known to be an opportunistic pathogen in humans with high relevance in multidrug-resistant nosocomial infections. The most promising bioactive barbiturates were studied in silico with emphasis on compliance with the Lipinski's rule of five as well as several pharmacokinetics and toxicity parameters. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Monoalkylated barbiturate derivatives: X-ray crystal structure, theoretical studies, and biological activities

NASA Astrophysics Data System (ADS)

Barakat, Assem; Al-Majid, Abdullah Mohammed; Soliman, Saied M.; Islam, Mohammad Shahidul; Ghawas, Hussain Mansur; Yousuf, Sammer; Choudhary, M. Iqbal; Wadood, Abdul

2017-08-01

Barbiturate derivatives are privileged structures with a broad range of pharmaceutical applications. We prepared a series of 5-monoalkylated barbiturate derivatives (3a-l) and evaluated, in vitro, their antioxidant (DPPH assay), and α-glucosidase inhibitory activities. Compounds 3a-l were synthesized via Michael addition. The structure of compound 3k was determined using X-ray single-crystal diffraction, and geometric parameters were calculated using density functional theory at the B3LYP/6-311G(d,p) level of theory. Further, the structural analysis of 3k were also investigated. Biological studies revealed that compounds 3b (IC50 = 133.1 ± 3.2 μM), 3d (IC50 = 305 ± 7.7 μM), and 3e (IC50 = 184 ± 2.3 μM) have potent α-glucosidase enzyme inhibitors and showed greater activity than the standard drug acarbose (IC50 = 841 ± 1.73 μM). Compounds 3a-3i were found to show weak antioxidant activity against 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radicals (IC50 = 91 ± 0.75 to 122 ± 1.0 μM) when tested against a standard antioxidant, gallic acid (IC50 = 23 ± 0.43 μM).

High-dose phenobarbital with intermittent short-acting barbiturates for acute encephalitis with refractory, repetitive partial seizures.

PubMed

Uchida, Takashi; Takayanagi, Masaru; Kitamura, Taro; Nishio, Toshiyuki; Numata, Yurika; Endo, Wakaba; Haginoya, Kazuhiro; Ohura, Toshihiro

2016-08-01

Acute encephalitis with refractory, repetitive partial seizures (AERRPS) is characterized by repetitive seizures during the acute and chronic phases and has a poor neurological outcome. Burst-suppression coma via continuous i.v. infusion of a short-acting barbiturate is used to terminate refractory seizures, but the severe side-effects of short-acting barbiturates are problematic. We report on a 9-year-old boy with AERRPS who was effectively treated with very-high-dose phenobarbital (VHDPB) combined with intermittent short-acting barbiturates. VHDPB side-effects were mild, especially compared with those associated with continuous i.v. infusion of short-acting barbiturates (dosage, 40-75 mg/kg/day; maximum blood level, 290 μg/mL). Using VHDPB as the main treatment, short-acting barbiturates were used intermittently and in small amounts. This is the first report to show that VHDPB, combined with intermittent short-acting barbiturates, can effectively treat AERRPS. After treatment, convulsions were suppressed and daily life continued, but intellectual impairment and high-level dysfunction remained. © 2016 Japan Pediatric Society.

A BARBITURATE ANTIDOTE—Use of Methylethylglutarimide in Barbiturate Intoxication and in Terminating Barbiturate Anesthesia

PubMed Central

Marmer, Milton J.

1959-01-01

Methylethylglutarimide was administered to 488 patients ranging in age from 7 to 89 years, in a study on sleep-reversal after harbiturate anesthesia. Sodium surital or sodium pentothal were the barbiturates used. The drug was administered intravenously in doses varying from 25 to 200 mg. Dosage below 25 mg. was found to be ineffective. Almost all patients showed signs of awakening as evidenced by the return of corneal and conjunctival reflexes, the opening of the eyes, and stirring or moving about. Many responded to questioning. Almost all showed evidence of greater responsiveness within five minutes. No untoward reactions were noted. No convulsions were produced. Five patients ranging in age from 24 to 70 years were treated for barbiturate poisoning with Mikedimide® given intravenously in doses varying from 550 mg. to 1950 mg. All recovered consciousness within 30 minutes to an hour. No convulsions were produced. While it is not known whether Mikedimide is a direct barbiturate antagonist, or whether it is an analeptic, it appears to be a useful drug in reversing the respiratory depression and the cerebral depression produced by harbiturate intoxication and barbiturate anesthesia. PMID:14421358

The Hydrogen Bonded Structures of Two 5-Bromobarbituric Acids and Analysis of Unequal C5–X and C5–X′ Bond Lengths (X = X′ = F, Cl, Br or Me) in 5,5-Disubstituted Barbituric Acids

PubMed Central

Gelbrich, Thomas; Braun, Doris E.; Oberparleiter, Stefan; Schottenberger, Herwig; Griesser, Ulrich J.

2017-01-01

The crystal structure of the methanol hemisolvate of 5,5-dibromobarbituric acid (1MH) displays an H-bonded layer structure which is based on N–H⋯O=C, N–H⋯O(MeOH) and (MeOH)O–H⋯O interactions. The barbiturate molecules form an H-bonded substructure which has the fes topology. 5,5′-Methanediylbis(5-bromobarbituric acid) 2, obtained from a solution of 5,5-dibromobarbituric acid in nitromethane, displays a N–H⋯O=C bonded framework of the sxd type. The conformation of the pyridmidine ring and the lengths of the ring substituent bonds C5–X and C5–X′ in crystal forms of 5,5-dibromobarbituric acid and three closely related analogues (X = X′ = Br, Cl, F, Me) have been investigated. In each case, a conformation close to a C5-endo envelope is correlated with a significant lengthening of the axial C5–X′ in comparison to the equatorial C5–X bond. Isolated molecule geometry optimizations at different levels of theory confirm that the C5-endo envelope is the global conformational energy minimum of 5,5-dihalogenbarbituric acids. The relative lengthening of the axial bond is therefore interpreted as an inherent feature of the preferred envelope conformation of the pyrimidine ring, which minimizes repulsive interactions between the axial substituent and pyrimidine ring atoms. PMID:28670485

Energy expenditure during barbiturate coma.

PubMed

Ashcraft, Christine M; Frankenfield, David C

2013-10-01

Barbiturate coma may have a significant effect on metabolic rate, but the phenomenon is not extensively studied. The primary purpose of the current study was to compare the metabolic rate of general critical care patients with those requiring barbiturate coma. A secondary purpose was to evaluate the accuracy of the Penn State prediction equation between these 2 groups of patients. Indirect calorimetry was used to measure the resting metabolic rate of mechanically ventilated, critically ill patients in a barbiturate coma and those of similar height, weight, and age but not in a barbiturate coma. Measurements of resting metabolic rate were compared with predictions using the Penn State equation accounting for body size, body temperature, and minute ventilation. The barbiturate coma group had a lower resting metabolic rate than the control group that remained lower even after adjustment for predicted healthy metabolic rate and maximum body temperature (1859 ± 290 vs 2037 ± 289 kcal/d, P = .020). When minute ventilation was also included in the analysis, the resting metabolic rate between the groups became statistically insignificant (1929 ± 229 vs 2023 ± 226 kcal/d, P = .142). The Penn State equation, which uses these variables, was accurate in 73% of the control patients and also the barbiturate coma patients. Resting metabolic rate is moderately reduced in barbiturate coma, but the decrease is out of proportion with changes in body temperature. However, if both body temperature and minute ventilation are considered, then the change is predictable.

Accurate and computationally efficient prediction of thermochemical properties of biomolecules using the generalized connectivity-based hierarchy.

PubMed

Sengupta, Arkajyoti; Ramabhadran, Raghunath O; Raghavachari, Krishnan

2014-08-14

In this study we have used the connectivity-based hierarchy (CBH) method to derive accurate heats of formation of a range of biomolecules, 18 amino acids and 10 barbituric acid/uracil derivatives. The hierarchy is based on the connectivity of the different atoms in a large molecule. It results in error-cancellation reaction schemes that are automated, general, and can be readily used for a broad range of organic molecules and biomolecules. Herein, we first locate stable conformational and tautomeric forms of these biomolecules using an accurate level of theory (viz. CCSD(T)/6-311++G(3df,2p)). Subsequently, the heats of formation of the amino acids are evaluated using the CBH-1 and CBH-2 schemes and routinely employed density functionals or wave function-based methods. The calculated heats of formation obtained herein using modest levels of theory and are in very good agreement with those obtained using more expensive W1-F12 and W2-F12 methods on amino acids and G3 results on barbituric acid derivatives. Overall, the present study (a) highlights the small effect of including multiple conformers in determining the heats of formation of biomolecules and (b) in concurrence with previous CBH studies, proves that use of the more effective error-cancelling isoatomic scheme (CBH-2) results in more accurate heats of formation with modestly sized basis sets along with common density functionals or wave function-based methods.

Thiobarbiturate and barbiturate salts of pefloxacin drug: Growth, structure, thermal stability and IR-spectra

NASA Astrophysics Data System (ADS)

Golovnev, Nicolay N.; Molokeev, Maxim S.; Lesnikov, Maxim K.; Sterkhova, Irina V.; Atuchin, Victor V.

2017-12-01

Three new salts of pefloxacin (PefH) with thiobarbituric (H2tba) and barbituric (H2ba) acids, pefloxacinium 2-thiobarbiturate trihydrate, PefH2(Htba)·3H2O (1), pefloxacinium 2-thiobarbiturate, PefH2(Htba) (2) and bis(pefloxacinium barbiturate) hydrate, (PefH2)2(Hba)2·2.56H2O (3) are synthesized and structurally characterized by the X-ray single-crystal diffraction. The structures of 1-3 contain intramolecular hydrogen bonds Csbnd H⋯F, Osbnd H⋯O. Intermolecular hydrogen bonds Nsbnd H⋯O and Osbnd H⋯O form a 2D plane network in 1. In 2 and 3, intermolecular hydrogen bonds Nsbnd H⋯O form the infinite chains. In 1-3, the Htba- and Hba- ions are connected with PefH2+ only by one intermolecular hydrogen bond Nsbnd H⋯O. In 2 and 3, two Htba- and Hba- ions are connected by two hydrogen bonds Nsbnd H⋯O. These pairs form infinite chains. All three structures are stabilized by the π-π interactions of the head-to-tail type between PefH2+ ions. Compounds 2 and 3 are characterized by powder XRD, TG-DSC and FT-IR.

Synthesis and characterization of Cu(II)-based anticancer chemotherapeutic agent targeting topoisomerase Iα: in vitro DNA binding, pBR322 cleavage, molecular docking studies and cytotoxicity against human cancer cell lines.

PubMed

Tabassum, Sartaj; Zaki, Mehvash; Afzal, Mohd; Arjmand, Farukh

2014-03-03

New metal-based anticancer chemotherapeutic drug candidates [Cu(phen)L](NO₃)₂ (1) and [Zn(phen)L](NO₃)₂ (2) were synthesized from ligand L (derived from pharmacophore scaffold barbituric acid and pyrazole). In vitro DNA binding studies of the L, 1 and 2 were carried out by various biophysical techniques revealing electrostatic mode. Complex 1 cleaves pBR322 DNA via oxidative pathway and recognizes major groove of DNA double helix. The molecular docking study was carried out to ascertain the mode of action towards the molecular target DNA and enzymes. The complex 1 exhibited remarkably good anticancer activity on a panel of human cancer cell lines (GI₅₀ values < 10 μg/ml), and to elucidate the mechanism of cancer inhibition, Topo-I enzymatic activity was carried out. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Merocyanine-type dyes from barbituric acid derivatives.

PubMed

Rezende, M C; Campodonico, P; Abuin, E; Kossanyi, J

2001-05-01

The preparation and the solvatochromic behavior of two dyes, obtained by condensation of N,N'-dimethylbarbituric acid with dimethylaminobenzaldehyde and with 4,4'-bis(N,N-dimethylamino)benzophenone (Michler's ketone) are described. The latter dye is rather sensitive to the polarity of the medium, and in particular, to the hydrogen-bond-donor ability of protic solvents. The solvatochromism of both compounds is discussed in terms of the pi* and E(T)(30) solvent polarity scales and their differences in behavior interpreted with the aid of semiempirical calculations.

Formation of a hydrogen-bonded barbiturate [2]-rotaxane.

PubMed

Tron, Arnaud; Thornton, Peter J; Rocher, Mathias; Jacquot de Rouville, Henri-Pierre; Desvergne, Jean-Pierre; Kauffmann, Brice; Buffeteau, Thierry; Cavagnat, Dominique; Tucker, James H R; McClenaghan, Nathan D

2014-03-07

Interlocked structures containing the classic Hamilton barbiturate binding motif comprising two 2,6-diamidopyridine units are reported for the first time. Stable [2]-rotaxanes can be accessed either through hydrogen-bonded preorganization by a barbiturate thread followed by a Cu(+)-catalyzed "click" stoppering reaction or by a Cu(2+)-mediated Glaser homocoupling reaction.

Reversible photocapture of a [2]rotaxane harnessing a barbiturate template.

PubMed

Tron, Arnaud; Thornton, Peter J; Lincheneau, Christophe; Desvergne, Jean-Pierre; Spencer, Neil; Tucker, James H R; McClenaghan, Nathan D

2015-01-16

Photoirradiation of a hydrogen-bonded molecular complex comprising acyclic components, namely, a stoppered thread (1) with a central barbiturate motif and an optimized doubly anthracene-terminated acyclic Hamilton-like receptor (2b), leads to an interlocked architecture, which was isolated and fully characterized. The sole isolated interlocked photoproduct (Φ = 0.06) is a [2]rotaxane, with the dimerized anthracenes assuming a head-to-tail geometry, as evidenced by NMR spectroscopy and consistent with molecular modeling (PM6). A different behavior was observed on irradiating homologous molecular complexes 1⊂2a, 1⊂2b, and 1⊂2c, where the spacers of 2a, 2b, and 2c incorporated 3, 6, and 9 methylene units, respectively. While no evidence of interlocked structure formation was observed following irradiation of 1⊂2a, a kinetically labile rotaxane was obtained on irradiating the complex 1⊂2c, and ring slippage was revealed. A more stable [2]rotaxane was formed on irradiating 1⊂2b, whose capture is found to be fully reversible upon heating, thereby resetting the system, with some fatigue (38%) after four irradiation–thermal reversion cycles.

Extracorporeal treatment for barbiturate poisoning: recommendations from the EXTRIP Workgroup.

PubMed

Mactier, Robert; Laliberté, Martin; Mardini, Joelle; Ghannoum, Marc; Lavergne, Valery; Gosselin, Sophie; Hoffman, Robert S; Nolin, Thomas D

2014-09-01

The EXTRIP (Extracorporeal Treatments in Poisoning) Workgroup conducted a systematic review of barbiturate poisoning using a standardized evidence-based process to provide recommendations on the use of extracorporeal treatment (ECTR) in patients with barbiturate poisoning. The authors reviewed all articles, extracted data, summarized key findings, and proposed structured voting statements following a predetermined format. A 2-round modified Delphi method was used to reach a consensus on voting statements, and the RAND/UCLA Appropriateness Method was used to quantify disagreement. 617 articles met the search inclusion criteria. Data for 538 patients were abstracted and evaluated. Only case reports, case series, and nonrandomized observational studies were identified, yielding a low quality of evidence for all recommendations. Using established criteria, the workgroup deemed that long-acting barbiturates are dialyzable and short-acting barbiturates are moderately dialyzable. Four key recommendations were made. (1) The use of ECTR should be restricted to cases of severe long-acting barbiturate poisoning. (2) The indications for ECTR in this setting are the presence of prolonged coma, respiratory depression necessitating mechanical ventilation, shock, persistent toxicity, or increasing or persistently elevated serum barbiturate concentrations despite treatment with multiple-dose activated charcoal. (3) Intermittent hemodialysis is the preferred mode of ECTR, and multiple-dose activated charcoal treatment should be continued during ECTR. (4) Cessation of ECTR is indicated when clinical improvement is apparent. This report provides detailed descriptions of the rationale for all recommendations. In summary, patients with long-acting barbiturate poisoning should be treated with ECTR provided at least one of the specific criteria in the first recommendation is present. Copyright © 2014 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

[Prolonged clinical pattern of brain death in patients under barbiturate sedation: usefulness of transcranial Doppler].

PubMed

Segura, T; Jiménez, P; Jerez, P; García, F; Córcoles, V

2002-04-01

Throughout the world, is fully accepted that a person is dead when brain death exists. In most situations, neurological criteria permit the diagnosis of brain death, but in some instances, as when high-dose barbiturate therapy has been used, confirmatory testing are required by law. We report the case of a 17 year-old women who suffered high-dose barbiturate therapy due to post traumatic intracranial hypertension. During the period of the barbiturate infusion and until six days after the suppression of this therapy, neurological exploration and EEG findings seem to confirm brain death, while transcranial Doppler (TCD) study remained normal. TCD is a fast, simple and accurate confirmatory testing in the determination of brain death and its findings are not affected by high-dose barbiturate therapy. We think that TCD must be present in all hospitals where mechanical ventilation and support of patients are carried out.

Journal of Special Operations Medicine, Volume 2, Edition 3

DTIC Science & Technology

2002-01-01

propranolol, methyldopa, guanethidine Thyroid hormones--thyroxine Hallucinogens--LSD Salicylates, barbiturates General anesthetics --halothane...Alcohol LSD, lysergic acid diethylamide. Volume 2, Edition 3 / Summer 02 21 must be available and palatable , and water intake must be monitored. Water... palatability are controversial. High sugar solutions may impede water absorption. Salt losses should be made up (during the first 2 weeks in a hot

Barbiturates for the treatment of alcohol withdrawal syndrome: A systematic review of clinical trials.

PubMed

Mo, Yoonsun; Thomas, Michael C; Karras, George E

2016-04-01

To perform a systematic review of the clinical trials concerning the use of barbiturates for the treatment of acute alcohol withdrawal syndrome (AWS). A literature search of MEDLINE, EMBASE, and the Cochrane Library, together with a manual citation review was conducted. We selected English-language clinical trials (controlled and observational studies) evaluating the efficacy and safety of barbiturates compared with benzodiazepine (BZD) therapy for the treatment of AWS in the acute care setting. Data extracted from the included trials were duration of delirium, number of seizures, length of intensive care unit and hospital stay, cumulated doses of barbiturates and BZDs, and respiratory or cardiac complications. Seven studies consisting of 4 prospective controlled and 3 retrospective trials were identified. Results from all the included studies suggest that barbiturates alone or in combination with BZDs are at least as effective as BZDs in the treatment of AWS. Furthermore, barbiturates appear to have acceptable tolerability and safety profiles, which were similar to those of BZDs in patients with AWS. Although the evidence is limited, based on our findings, adding phenobarbital to a BZD-based regimen is a reasonable option, particularly in patients with BZD-refractory AWS. Copyright © 2015 Elsevier Inc. All rights reserved.

Occurrence and fate of barbiturates in the aquatic environment.

PubMed

Peschka, Manuela; Eubeler, Jan P; Knepper, Thomas P

2006-12-01

Barbiturates have been widely used as sedative hypnotics in the mid-1960s and since then mainly as veterinary drugs. To monitor their presence and fate in the aquatic environment, a method based on gas chromatography-mass spectrometry (GC-MS) has been developed to quantify butalbital, secobarbital, hexobarbital, aprobarbital, phenobarbital, and pentobarbital, all with a limit of detection (LOD) down to 1 ng/L. From the various investigated waste and surface water samples, barbiturates were only, but regularly detected in the Mulde, a tributary of the river Elbe in Germany at relevant concentrations up to several microg/L. Investigations of groundwater being affected with wastewater infiltration several decades ago also revealed a barbiturate pattern, indicating a strong recalcitrance of these drugs. To confirm this hypothesis, studies were carried out on biotic and abiotic degradation. Both, the biodegradability under aerobic conditions and hydrolysis did not show any degradation, implementing, that the investigated barbiturates, once released into the aquatic environment, show high stability over a long period of time.

The history of barbiturates a century after their clinical introduction

PubMed Central

López-Muñoz, Francisco; Ucha-Udabe, Ronaldo; Alamo, Cecilio

2005-01-01

The present work offers an analysis of the historical development of the discovery and use of barbiturates in the field of psychiatry and neurology, a century after their clinical introduction. Beginning with the synthesis of malonylurea by von Baeyer in 1864, and up to the decline of barbiturate therapy in the 1960s, it describes the discovery of the sedative properties of barbital, by von Mering and Fischer (1903), the subsequent synthesis of phenobarbital by this same group (1911), and the gradual clinical incorporation of different barbiturates (butobarbital, amobarbital, secobarbital, pentobarbital, thiopental, etc). We describe the role played in therapy by barbiturates throughout their history: their traditional use as sedative and hypnotic agents, their use with schizophrenic patients in so-called “sleep cures” (Klaesi, Cloetta), the discovery of the antiepileptic properties of phenobarbital (Hauptmann) and their use in the treatment of epilepsy, and the introduction of thiobarbiturates in intravenous anesthesia (Lundy, Waters). We also analyze, from the historical perspective, the problems of safety (phenomena of dependence and death by overdose) which, accompanied by the introduction of a range of psychoactive drugs in the 1950s, brought an end to barbiturate use, except in specific applications, such as the induction of anesthesia and the treatment of certain types of epileptic crisis. PMID:18568113

Midazolam fails to prevent neurological damage in children with convulsive refractory febrile status epilepticus.

PubMed

Nagase, Hiroaki; Nishiyama, Masahiro; Nakagawa, Taku; Fujita, Kyoko; Saji, Yohsuke; Maruyama, Azusa

2014-07-01

We conducted a retrospective study to compare the outcome of intravenous midazolam infusion without electroencephalography or targeted temperature management and barbiturate coma therapy with electroencephalography and targeted temperature management for treating convulsive refractory febrile status epilepticus. Of 49 consecutive convulsive refractory febrile status epilepticus patients admitted to the pediatric intensive care unit of our hospital, 29 were excluded because they received other treatments or because of various underlying illnesses. Thus, eight patients were treated with midazolam and 10 with barbiturate coma therapy using thiamylal. Midazolam-treated patients were intubated only when necessary, whereas barbiturate coma therapy patients were routinely intubated. Continuous electroencephalography monitoring was utilized only for the barbiturate coma group. The titration goal for anesthesia was clinical termination of status epilepticus in the midazolam group and suppression or burst-suppression patterns on electroencephalography in the barbiturate coma group. Normothermia was maintained using blankets and neuromuscular blockade in the barbiturate coma group and using antipyretics in the midazolam group. Prognoses were measured at 1 month after onset; children were classified into poor and good outcome groups. Good outcome was achieved in all the barbiturate coma group patients and 50% of the midazolam group patients (P = 0.02, Fisher's exact test). Although the sample size was small and our study could not determine which protocol element is essential for the neurological outcome, the findings suggest that clinical seizure control using midazolam without continuous electroencephalography monitoring or targeted temperature management is insufficient in preventing neurological damage in children with convulsive refractory febrile status epilepticus. Copyright © 2014 Elsevier Inc. All rights reserved.

Thiopental Anesthesia and Tannic Acid Diagnostic Enemas

PubMed Central

Singh, Jasbir; Boyd, Eldon M.

1966-01-01

The administration to albino rats of tannic acid as a retention enema (in doses of 0.2 g./kg. body weight and over) prolonged the duration of anesthesia induced by thiopental given immediately before, or 72 hours after, the tannic acid. This dose of tannic acid corresponds, on the basis of body weight, to a radiodiagnostic enema of 2 1. of 0.25% tannic acid in barium sulfate suspension given to a child weighing 25 kg. By excluding certain hypothermic effects of tannic acid, it was concluded that thiopental potentiation was probably due to impairment by the tannic acid of the liver's ability to detoxify the barbiturate. The results suggest that a drug which is detoxified in the liver should be administered three to five days after a tannic acid-barium sulfate radiodiagnostic enema only with considerable caution. PMID:5947612

Barbiturate intoxication and overdose

MedlinePlus

... breathing Slow, slurred speech Sluggishness Staggering Excessive and long-term use of barbiturates, such as phenobarbital, may produce the following chronic symptoms: Changes in alertness Decreased functioning Irritability Memory loss

21 CFR 862.3150 - Barbiturate test system.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Toxicology Test Systems § 862... in monitoring levels of barbiturate to ensure appropriate therapy. (b) Classification. Class II. ...

4 CFR 25.8 - Alcoholic beverages and narcotics.

Code of Federal Regulations, 2014 CFR

2014-01-01

... alcoholic beverages, narcotic drugs, hallucinogens, marijuana, barbiturates, or amphetamines is prohibited..., marijuana, barbiturate, or amphetamine. This prohibition shall not apply in cases where the drug is being...

4 CFR 25.8 - Alcoholic beverages and narcotics.

Code of Federal Regulations, 2011 CFR

2011-01-01

... alcoholic beverages, narcotic drugs, hallucinogens, marijuana, barbiturates, or amphetamines is prohibited..., marijuana, barbiturate, or amphetamine. This prohibition shall not apply in cases where the drug is being...

4 CFR 25.8 - Alcoholic beverages and narcotics.

Code of Federal Regulations, 2012 CFR

2012-01-01

... alcoholic beverages, narcotic drugs, hallucinogens, marijuana, barbiturates, or amphetamines is prohibited..., marijuana, barbiturate, or amphetamine. This prohibition shall not apply in cases where the drug is being...

4 CFR 25.8 - Alcoholic beverages and narcotics.

Code of Federal Regulations, 2010 CFR

2010-01-01

... alcoholic beverages, narcotic drugs, hallucinogens, marijuana, barbiturates, or amphetamines is prohibited..., marijuana, barbiturate, or amphetamine. This prohibition shall not apply in cases where the drug is being...

4 CFR 25.8 - Alcoholic beverages and narcotics.

Code of Federal Regulations, 2013 CFR

2013-01-01

... alcoholic beverages, narcotic drugs, hallucinogens, marijuana, barbiturates, or amphetamines is prohibited..., marijuana, barbiturate, or amphetamine. This prohibition shall not apply in cases where the drug is being...

Functional Chemical Groups that May Likely Become a Source for the Synthesis of Novel Central Nervous System (CNS) Acting Drugs.

PubMed

Saganuwan, Saganuwan A

2017-01-01

Central Nervous System (CNS) disorders are on increase perhaps due to genetic, enviromental, social and dietetic factors. Unfortunately, a large number of CNS drugs have adverse effects such as addiction, tolerance, psychological and physical dependence. In view of this, literature search was carried out with a view to identify functional chemical groups that may serve as lead molecules for synthesis of compounds that may have CNS activity. The search revealed that heterocycles that have heteroatoms such as nitrogen (N), sulphur (S) and oxygen (O) form the largest class of organic compounds. They replace carbon in a benzene ring to form pyridine. Compounds with furan, thiophene, pyrrole, pyridine, azole, imidazole, indole, purine, pyrimidine, esters, carboxylic acid, aldehyde, pyrylium, pyrone, pyrodine, barbituric acid, barbiturate, quinoline, quinolone, isoquinolone, coumarin, alkylpyridine, picoline, piperidine, diazine, carboxamide, flavonoid glycoside, oxindole, aminophenol, benzimidazole, benzoxazole, benzothiazole, and chromone chemical groups among others may have CNS effects ranging from depression passing through euphoria to convulsion. Examples of the compounds with the functional groups include but not limited to coal tar, pyridostigmine, pralidoxime, quinine, mefloquine, pyrilamine, pyronaridine, ciprofloxacin and piroxicam. A number of them can undergo keto-enol tautomerism. Chiral amines may be used for derivation of chiral carboxylic acids which are components of tautomers. Some tautomers may cause parkinsonism and Stevens Johnson syndrome. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

32 CFR 228.9 - Prohibition on narcotics and illegal substances.

Code of Federal Regulations, 2014 CFR

2014-07-01

... narcotic drug, hallucinogen, marijuana, barbiturate or amphetamine is prohibited. Operation of a motor..., hallucinogens, marijuana, barbiturates or amphetamines is also prohibited. These prohibitions shall not apply in...

32 CFR 228.9 - Prohibition on narcotics and illegal substances.

Code of Federal Regulations, 2011 CFR

2011-07-01

... narcotic drug, hallucinogen, marijuana, barbiturate or amphetamine is prohibited. Operation of a motor..., hallucinogens, marijuana, barbiturates or amphetamines is also prohibited. These prohibitions shall not apply in...

32 CFR 228.9 - Prohibition on narcotics and illegal substances.

Code of Federal Regulations, 2013 CFR

2013-07-01

... narcotic drug, hallucinogen, marijuana, barbiturate or amphetamine is prohibited. Operation of a motor..., hallucinogens, marijuana, barbiturates or amphetamines is also prohibited. These prohibitions shall not apply in...

32 CFR 228.9 - Prohibition on narcotics and illegal substances.

Code of Federal Regulations, 2012 CFR

2012-07-01

... narcotic drug, hallucinogen, marijuana, barbiturate or amphetamine is prohibited. Operation of a motor..., hallucinogens, marijuana, barbiturates or amphetamines is also prohibited. These prohibitions shall not apply in...

32 CFR 228.9 - Prohibition on narcotics and illegal substances.

Code of Federal Regulations, 2010 CFR

2010-07-01

... narcotic drug, hallucinogen, marijuana, barbiturate or amphetamine is prohibited. Operation of a motor..., hallucinogens, marijuana, barbiturates or amphetamines is also prohibited. These prohibitions shall not apply in...

Mapping General Anesthetic Sites in Heteromeric γ-Aminobutyric Acid Type A Receptors Reveals a Potential For Targeting Receptor Subtypes.

PubMed

Forman, Stuart A; Miller, Keith W

2016-11-01

IV general anesthetics, including propofol, etomidate, alphaxalone, and barbiturates, produce important actions by enhancing γ-aminobutyric acid type A (GABAA) receptor activation. In this article, we review scientific studies that have located and mapped IV anesthetic sites using photoaffinity labeling and substituted cysteine modification protection. These anesthetics bind in transmembrane pockets between subunits of typical synaptic GABAA receptors, and drugs that display stereoselectivity also show remarkably selective interactions with distinct interfacial sites. These results suggest strategies for developing new drugs that selectively modulate distinct GABAA receptor subtypes.

Succinate and artificial maintenance of normal body temperature synergistically correct lethal disorders in thiopental coma rat.

PubMed

Ivnitsky, Jury Ju; Rejniuk, Vladimir L; Schäfer, Timur V; Malakhovsky, Vladimir N

2006-01-20

Under modeling of thiopental coma influence of sodium succinate and (or) external warming for the support of normal body temperature (isothermal regimen) on the gas exchange, blood gas content, acid-base status and survival rate was studied in rats. In the absence of therapy hypothermia was developed (-9.4 degrees C), O(2) consumption decreased by a factor 5, oxygenation of arterial blood (pO(2)) did not change while that of venous blood increased, where with arteriovenous oxygen tension gradient decreased by half. Blood tension of carbon dioxide (pCO(2)) increased twice, respiratory and metabolic acidosis was developed. Survival rate under absence of a therapy was 42%, with isolated use of isothermal regimen or succinate therapy alike-50%; with their use in combination drastically increased up to 92%. Succinate increased arteriovenous gradient of pO(2), decreased deficit of buffer bases, increased bicarbonate concentration. At isothermal regimen accumulation of CO(2) in the blood was diminished, its excretion was increased, pH of blood approached normal values. Combined use of both therapy agents increased O(2) consumption and potentiated their positive influence on acid-base status. The implication is that hypothermia restrains effect of succinate in barbiturate coma; prevention of hypothermia in combination with succinate administration is highly effective method of experimental therapy of barbiturate intoxication.

Liposome-based mucus-penetrating particles (MPP) for mucosal theranostics: demonstration of diamagnetic chemical exchange saturation transfer (diaCEST) magnetic resonance imaging (MRI).

PubMed

Yu, Tao; Chan, Kannie W Y; Anonuevo, Abraham; Song, Xiaolei; Schuster, Benjamin S; Chattopadhyay, Sumon; Xu, Qingguo; Oskolkov, Nikita; Patel, Himatkumar; Ensign, Laura M; van Zjil, Peter C M; McMahon, Michael T; Hanes, Justin

2015-02-01

Mucus barriers lining mucosal epithelia reduce the effectiveness of nanocarrier-based mucosal drug delivery and imaging ("theranostics"). Here, we describe liposome-based mucus-penetrating particles (MPP) capable of loading hydrophilic agents, e.g., the diaCEST MRI contrast agent barbituric acid (BA). We observed that polyethylene glycol (PEG)-coated liposomes containing ≥7 mol% PEG diffused only ~10-fold slower in human cervicovaginal mucus (CVM) compared to their theoretical speeds in water. 7 mol%-PEG liposomes contained sufficient BA loading for diaCEST contrast, and provided improved vaginal distribution compared to 0 and 3mol%-PEG liposomes. However, increasing PEG content to ~12 mol% compromised BA loading and vaginal distribution, suggesting that PEG content must be optimized to maintain drug loading and stability. Non-invasive diaCEST MRI illustrated uniform vaginal coverage and longer retention of BA-loaded 7 mol%-PEG liposomes compared to unencapsulated BA. Liposomal MPP with optimized PEG content hold promise for drug delivery and imaging at mucosal surfaces. This team of authors characterized liposome-based mucus-penetrating particles (MPP) capable of loading hydrophilic agents, such as barbituric acid (a diaCEST MRI contrast agent) and concluded that liposomal MPP with optimized PEG coating enables drug delivery and imaging at mucosal surfaces. Copyright © 2015 Elsevier Inc. All rights reserved.

Desorption electrospray ionization (DESI) with atmospheric pressure ion mobility spectrometry for drug detection.

PubMed

Roscioli, Kristyn M; Tufariello, Jessica A; Zhang, Xing; Li, Shelly X; Goetz, Gilles H; Cheng, Guilong; Siems, William F; Hill, Herbert H

2014-04-07

Desorption electrospray ionization (DESI) was coupled to an ambient pressure drift tube ion mobility time-of-flight mass spectrometer (IM-TOFMS) for the direct analysis of active ingredients in pharmaceutical samples. The DESI source was also coupled with a standalone IMS demonstrating potential of portable and inexpensive drug-quality testing platforms. The DESI-IMS required no sample pretreatment as ions were generated directly from tablets and cream formulations. The analysis of a range of over-the-counter and prescription tablet formations was demonstrated for amphetamine (methylphenidate), antidepressant (venlafaxine), barbiturate (Barbituric acid), depressant (alprazolam), narcotic (3-methylmorphine) and sympatholytic (propranolol) drugs. Active ingredients from soft and liquid formulations, such as Icy Hot cream (methyl salicylate) and Nyquil cold medicine (acetaminophen, dextromethorphan, doxylamine) were also detected. Increased sensitivity for selective drug responses was demonstrated through the formation of sodiated adduct ions by introducing small quantities of NaCl into the DESI solvent. Of the drugs and pharmaceuticals tested in this study, 68% (22 total samples) provided a clear ion mobility response at characteristic mobilities either as (M + H)(+), (M - H)(-), or (M + Na)(+) ions.

Synthesis of Barbiturate-Based Methionine Aminopeptidase-1 Inhibitors

PubMed Central

Haldar, Manas K.; Scott, Michael D.; Sule, Nitesh; Srivastava, D. K.; Mallik, Sanku

2008-01-01

The syntheses of a new class of barbiturate-based inhibitors for human and E. Coli Methionine Aminopeptidase -1 (MetAP-1) are described. Some of the synthesized inhibitors show selective inhibition of the human enzyme with high potency. PMID:18343108

Comparative Actions of Barbiturates Studied by Pollen Grain Germination.

ERIC Educational Resources Information Center

Kordan, Herbert A.; Mumford, Pauline M.

1979-01-01

Describes a simple experimental system whereby the comparative actions of long, medium, and short-acting barbiturates can be demonstrated in a relatively short period of time under optical microscopy using pollen grains as the biological test or assay system. (Author/HM)

38 CFR 1.218 - Security and law enforcement at VA facilities.

Code of Federal Regulations, 2012 CFR

2012-07-01

... the influence of alcoholic beverages, narcotic drugs, hallucinogens, marijuana, barbiturates, or amphetamines is prohibited. Entering property under the influence of any narcotic drug, hallucinogen, marijuana... property of any narcotic drug, hallucinogen, marijuana, barbiturate, or amphetamine (unless prescribed by a...

38 CFR 1.218 - Security and law enforcement at VA facilities.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the influence of alcoholic beverages, narcotic drugs, hallucinogens, marijuana, barbiturates, or amphetamines is prohibited. Entering property under the influence of any narcotic drug, hallucinogen, marijuana... property of any narcotic drug, hallucinogen, marijuana, barbiturate, or amphetamine (unless prescribed by a...

38 CFR 1.218 - Security and law enforcement at VA facilities.

Code of Federal Regulations, 2013 CFR

2013-07-01

... the influence of alcoholic beverages, narcotic drugs, hallucinogens, marijuana, barbiturates, or amphetamines is prohibited. Entering property under the influence of any narcotic drug, hallucinogen, marijuana... property of any narcotic drug, hallucinogen, marijuana, barbiturate, or amphetamine (unless prescribed by a...

38 CFR 1.218 - Security and law enforcement at VA facilities.

Code of Federal Regulations, 2014 CFR

2014-07-01

... the influence of alcoholic beverages, narcotic drugs, hallucinogens, marijuana, barbiturates, or amphetamines is prohibited. Entering property under the influence of any narcotic drug, hallucinogen, marijuana... property of any narcotic drug, hallucinogen, marijuana, barbiturate, or amphetamine (unless prescribed by a...

38 CFR 1.218 - Security and law enforcement at VA facilities.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the influence of alcoholic beverages, narcotic drugs, hallucinogens, marijuana, barbiturates, or amphetamines is prohibited. Entering property under the influence of any narcotic drug, hallucinogen, marijuana... property of any narcotic drug, hallucinogen, marijuana, barbiturate, or amphetamine (unless prescribed by a...

Tandem Aldol-Michael Reactions in Aqueous Diethylamine Medium: A Greener and Efficient Approach to Bis-Pyrimidine Derivatives

PubMed Central

Al-Majid, Abdullah M.; Barakat, Assem; AL-Najjar, Hany J.; Mabkhot, Yahia N.; Ghabbour, Hazem A.; Fun, Hoong-Kun

2013-01-01

A simple protocol, involving the green synthesis for the construction of novel bis-pyrimidine derivatives, 3a–i and 4a–e are accomplished by the aqueous diethylamine media promoted tandem Aldol-Michael reaction between two molecules of barbituric acid derivatives 1a,b with various aldehydes. This efficient synthetic protocol using an economic and environmentally friendly reaction media with versatility and shorter reaction time provides bis-pyrimidine derivatives with high yields (88%–99%). PMID:24317435

21 CFR 862.3150 - Barbiturate test system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Barbiturate test system. 862.3150 Section 862.3150 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Toxicology Test Systems § 862...

21 CFR 862.3150 - Barbiturate test system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Barbiturate test system. 862.3150 Section 862.3150 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Toxicology Test Systems § 862...

21 CFR 862.3150 - Barbiturate test system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Barbiturate test system. 862.3150 Section 862.3150 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Toxicology Test Systems § 862...

21 CFR 862.3150 - Barbiturate test system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Barbiturate test system. 862.3150 Section 862.3150 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Toxicology Test Systems § 862...

[Cerebral protection].

PubMed

Cattaneo, A D

1993-09-01

Cerebral protection means prevention of cerebral neuronal damage. Severe brain damage extinguishes the very "human" functions such as speech, consciousness, intellectual capacity, and emotional integrity. Many pathologic conditions may inflict injuries to the brain, therefore the protection and salvage of cerebral neuronal function must be the top priorities in the care of critically ill patients. Brain tissue has unusually high energy requirements, its stores of energy metabolites are small and, as a result, the brain is totally dependent on a continuous supply of substrates and oxygen, via the circulation. In complete global ischemia (cardiac arrest) reperfusion is characterized by an immediate reactive hyperemia followed within 20-30 min by a delayed hypoperfusion state. It has been postulated that the latter contributes to the ultimate neurologic outcome. In focal ischemia (stroke) the primary focus of necrosis is encircled by an area (ischemic penumbra) that is underperfused and contains neurotoxic substances such as free radicals, prostaglandins, calcium, and excitatory neurotransmitters. The variety of therapeutic effort that have addressed the question of protecting the brain reflects their limited success. 1) Barbiturates. After an initial enthusiastic endorsement by many clinicians and years of vigorous controversy, it can now be unequivocally stated that there is no place for barbiturate therapy following resuscitation from cardiac arrest. One presumed explanation for this negative statement is that cerebral metabolic suppression by barbiturates (and other anesthetics) is impossible in the absence of an active EEG. Conversely, in the event of incomplete ischemia EEG activity in usually present (albeit altered) and metabolic suppression and hence possibly protection can be induced with barbiturates. Indeed, most of the animal studies led to a number of recommendations for barbiturate therapy in man for incomplete ischemia. 2) Isoflurane. From a cerebral metabolic standpoint, exposure to isoflurane at concentration of 2 MAC is credited with providing the same potential for protection as high dose barbiturate (isoelectric EEG). A possible major difference between barbiturates and isoflurane is the modest cerebral vasodilation induced by the latter while barbiturates are associated with decreased CBF. This suggests that in focal ischemia isoflurane may elicit an intracerebral steal. 3) Calcium entry blockers. Some calcium entry blockers with the distinctive feature of acting preferably on cerebral as opposed to systemic vascular smooth muscles may exert beneficial effects during or after brain ischemia. Two such drugs which have shown promise are nimodipine and lidoflazine. In animal and human studies nimodipine has been reported to improve the neurologic outcome of both the cerebral vasospasm and the postischemic hypoperfusion state.(ABSTRACT TRUNCATED AT 400 WORDS)

[The role of gamma-aminobutyric acid in the mechanism of action of anticonvulsant drugs].

PubMed

Chmielewska, B

2000-01-01

Decreased activity of gamma-aminobutyric acid, the major inhibitory neurotransmitter in CNS can be epileptogenic. Manipulation of the GABA system has been a target for development of antiepileptic drugs. The different ways for augmenting gabaergic inhibition by conventional and new AEDs are presented in this paper. Among the I generation, barbiturates and benzodiazepines are potent anticonvulsants that act as GABA modulators in postsynaptic GABA-A receptor complex but their usefulness is limited by dependence and tolerance to antiseizure activity. The II generation drugs vigabatrin and tiagabine, and to some extent gabapentin have been developed by a rationale strategy and none of them exert direct action in GABA receptors. Only two former drugs exhibit selective, strictly defined activity: vigabatrine is an irreversible inhibitor of GABA-aminotransferase and tiagabine acts as a GABA-uptake inhibitor from synaptic cleft into neurons and glia. Gabapentin binds to a novel receptors in epileptogenic areas in CNS and enhances GABA turnover. Drugs with multiple mechanisms of action, felbamate and topiramate not only potentiate gabaergic inhibition in several ways but also diminish the activity of excitatory amino acids at their NMDA or AMPA receptors; the later mechanism seems to be essential for their potential neuroprotective activity in epileptogenesis. None of gabamimetic drugs provide optimal seizure control but better tolerability of newer ones and well-established mechanisms of action provide possible harmless therapy.

Barbiturates Block Sodium and Potassium Conductance Increases in Voltage-Clamped Lobster Axons

PubMed Central

Blaustein, M. P.

1968-01-01

Sodium pentobarbital and sodium thiopental decrease both the peak initial (Na) and late steady-state (K) currents and reduce the maximum sodium and potassium conductance increases in voltage-clamped lobster giant axons. These barbiturates also slow the rate at which the sodium conductance turns on, and shift the normalized sodium conductance vs. voltage curves in the direction of depolarization along the voltage axis. Since pentobarbital (pKa = 8.0) blocks the action potential more effectively at pH 8.5 than at pH 6.7, the anionic form of the drug appears to be active. The data suggest that these drugs affect the axon membrane directly, rather than secondarily through effects on intermediary metabolism. It is suggested that penetration of the lipid layer of the membrane by the nonpolar portion of the barbiturate molecules may cause the decrease in membrane conductances, while electrostatic interactions involving the anionic group on the barbiturate, divalent cations, and "fixed charges" in the membrane could account for the slowing of the rate of sodium conductance turn-on and the shift of the normalized conductance curves along the voltage axis. PMID:5648829

Efficient Synthesis and Antimicrobial Evaluation of Pyrazolopyranopyrimidines in the Presence of SBA-Pr-SO3H as a Nanoporous Acid Catalyst

PubMed Central

Mohammadi Ziarani, Ghodsi; Aleali, Faezeh; Lashgari, Negar; Badiei, Alireza; Abolhasani Soorki, Ali

2018-01-01

A simple, efficient, and environmentally friendly method has been developed for the synthesis of a series of tricyclic fused pyrazolopyranopyrimidines via a one-pot three-component reaction of barbituric acids, aromatic aldehydes, and 3-methyl-5-pyrazolone in the presence of SBA-Pr-SO3H. SBA-15 mesoporous silica material functionalized with propyl sulfonic acid groups was used as a heterogeneous Brønsted acid catalyst with hexagonal structure, high surface area, thick walls, and large uniform pores. All reactions were performed under reflux conditions in water in the presence of a catalytic amount of SBA-Pr-SO3H. High yields, mild reaction conditions, short reaction times, and simple work-up procedures are some advantages of this method. The antimicrobial activities of the synthesized compounds were also evaluated and some products exhibited significant antibacterial activities at low concentrations. PMID:29881410

Barbiturate ingestion in three adult captive tigers (Panthera tigris) and concomitant fatal botulism of one.

PubMed

Williams, J H; Bester, L; Venter, L; Pretorius, D; Greyling, F

2011-12-01

Zoo animals, including tigers, have been reported to suffer from barbiturate intoxication, with pentabarbitone being most commonly recorded. Clinical signs range from mild ataxia to general anaesthesia with recovery over hours to days with several factors affecting hepatic barbiturate metabolism and tissue partitioning. Botulism is an often fatal intoxication in man, animals, birds and certain fish. The occurrence in carnivores is uncommon to rare, with only 2 reports found of botulism in felids. This report relates to 3 adult captive cohabiting tigers that simultaneously developed signs of abdominal discomfort, progressive ataxia, recumbency and comatose sleep resembling stage 2 anaesthesia, alternating with periods of distracted wakefulness and ataxic movements. These signs occurred 4 days after being fed the carcass of a horse that had ostensibly died of colic and not been euthanased. The male tiger that was the dominant animal in the feeding hierarchy was worst affected and had to be given intravenous fluids. The female that was lowest in hierarchy was unaffected. After 48-72 hours of treatment at the Onderstepoort Veterinary Academic Hospital the females could eat and made an uneventful recovery. The male tiger showed partial recovery but died during the night a few hours after drinking water on his return to the owner. Necropsy revealed severe oesophageal dilation and impaction with decaying grass; some of this material and water were present in the pharynx and trachea, and had been aspirated causing acute widespread bronchopneumonia. Colon content tested negative for common pesticides but, together with liver, tested positive for barbiturate. Serum taken on the day of admission had tested negative for barbiturate and the residual serum from the 3 animals later tested negative for botulinum toxin. Colon and oesophageal content from the male at necropsy were positive for Clostridium botulinum toxin type C by the mouse bioassay neutralisation test, confirming that this male had had concomitant barbiturate toxicity and botulism, and had succumbed to aspiration bronchopneumonia secondary to pharyngeal, laryngeal and oesophageal paralysis and oesophageal

Effects of anticonvulsants in vivo on high affinity choline uptake in vitro in mouse hippocampal synaptosomes.

PubMed Central

Miller, J. A.; Richter, J. A.

1985-01-01

The effects of several anticonvulsant drugs on sodium-dependent high affinity choline uptake (HACU) in mouse hippocampal synaptosomes was investigated. HACU was measured in vitro after in vivo administration of the drug to mice. HACU was inhibited by drugs which have in common the ability to facilitate gamma-aminobutyric acid (GABA) transmission, pentobarbitone, phenobarbitone, barbitone, diazepam, chloridiazepoxide, and valproic acid. Dose-response relationships were determined for these drugs and the drugs' potencies at inhibiting HACU correlated well with their anticonvulsant potencies. Clonazepam, ethosuximide, carbamazepine, and barbituric acid had no effect on HACU in the doses used while phenytoin and trimethadione stimulated HACU. These results suggest that certain anticonvulsants may elicit a part of their anticonvulsant activity by modulating cholinergic neurones. This effect may be mediated through a GABA mechanism. PMID:3978310

Economic evaluation of decompressive craniectomy versus barbiturate coma for refractory intracranial hypertension following traumatic brain injury.

PubMed

Alali, Aziz S; Naimark, David M J; Wilson, Jefferson R; Fowler, Robert A; Scales, Damon C; Golan, Eyal; Mainprize, Todd G; Ray, Joel G; Nathens, Avery B

2014-10-01

Decompressive craniectomy and barbiturate coma are often used as second-tier strategies when intracranial hypertension following severe traumatic brain injury is refractory to first-line treatments. Uncertainty surrounds the decision to choose either treatment option. We investigated which strategy is more economically attractive in this context. We performed a cost-utility analysis. A Markov Monte Carlo microsimulation model with a life-long time horizon was created to compare quality-adjusted survival and cost of the two treatment strategies, from the perspective of healthcare payer. Model parameters were estimated from the literature. Two-dimensional simulation was used to incorporate parameter uncertainty into the model. Value of information analysis was conducted to identify major drivers of decision uncertainty and focus future research. Trauma centers in the United States. Base case was a population of patients (mean age = 25 yr) who developed refractory intracranial hypertension following traumatic brain injury. We compared two treatment strategies: decompressive craniectomy and barbiturate coma. Decompressive craniectomy was associated with an average gain of 1.5 quality-adjusted life years relative to barbiturate coma, with an incremental cost-effectiveness ratio of $9,565/quality-adjusted life year gained. Decompressive craniectomy resulted in a greater quality-adjusted life expectancy 86% of the time and was more cost-effective than barbiturate coma in 78% of cases if our willingness-to-pay threshold is $50,000/quality-adjusted life year and 82% of cases at a threshold of $100,000/quality-adjusted life year. At older age, decompressive craniectomy continued to increase survival but at higher cost (incremental cost-effectiveness ratio = $197,906/quality-adjusted life year at mean age = 85 yr). Based on available evidence, decompressive craniectomy for the treatment of refractory intracranial hypertension following traumatic brain injury provides better value in terms of costs and health gains than barbiturate coma. However, decompressive craniectomy might be less economically attractive for older patients. Further research, particularly on natural history of severe traumatic brain injury patients, is needed to make more informed treatment decisions.

Single-molecule force-conductance spectroscopy of hydrogen-bonded complexes

NASA Astrophysics Data System (ADS)

Pirrotta, Alessandro; De Vico, Luca; Solomon, Gemma C.; Franco, Ignacio

2017-03-01

The emerging ability to study physical properties at the single-molecule limit highlights the disparity between what is observable in an ensemble of molecules and the heterogeneous contributions of its constituent parts. A particularly convenient platform for single-molecule studies are molecular junctions where forces and voltages can be applied to individual molecules, giving access to a series of electromechanical observables that can form the basis of highly discriminating multidimensional single-molecule spectroscopies. Here, we computationally examine the ability of force and conductance to inform about molecular recognition events at the single-molecule limit. For this, we consider the force-conductance characteristics of a prototypical class of hydrogen bonded bimolecular complexes sandwiched between gold electrodes. The complexes consist of derivatives of a barbituric acid and a Hamilton receptor that can form up to six simultaneous hydrogen bonds. The simulations combine classical molecular dynamics of the mechanical deformation of the junction with non-equilibrium Green's function computations of the electronic transport. As shown, in these complexes hydrogen bonds mediate transport either by directly participating as a possible transport pathway or by stabilizing molecular conformations with enhanced conductance properties. Further, we observe that force-conductance correlations can be very sensitive to small changes in the chemical structure of the complexes and provide detailed information about the behavior of single molecules that cannot be gleaned from either measurement alone. In fact, there are regions during the elongation that are only mechanically active, others that are only conductance active, and regions where both force and conductance changes as the complex is mechanically manipulated. The implication is that force and conductance provide complementary information about the evolution of molecules in junctions that can be used to interrogate basic structure-transport relations at the single-molecule limit.

Changing pattern of drugs used for self-poisoning.

PubMed Central

Proudfoot, A T; Park, J

1978-01-01

In 1967-76 the annual number of admissions to a poisoning treatment centre rose from 964 to 2134. The proportion of admissions caused by taking barbiturate hypnotics and methaqualone fell considerably while that caused by taking benzodiazepines and tricyclic antidepressants increased. As a result the proportion of patients admitted unconscious fell from 23% to 15%. The declining contributions of barbiturates and methaqualone and increased importance of tricyclic antidepressants were significant in all grades of coma. The change in drugs taken, however, has not yet reduced the percentage of unconscious patients needing endotracheal intubation or assisted ventilation, and hypothermia remains as common. Only hypotension has become less frequent as antidepressants replace barbiturates as the main cause of drug-induced coma. The use of salicylates for self-poisoning is declining slowly, and paracetamol poisoning is now as common. PMID:620215

Protometric thermometric titrations of sparingly soluble compounds in water in the presence of n-octanol.

PubMed

Burgot, G; Burgot, J-L

2002-10-15

Thermometric titrimetry permits titration of acido-basic compounds in water in the presence of n-octanol. n-Octanol permits the solubilization of protolytes and moreover may also displace the equilibria of the titration reactions. Hydrochlorides of highly insoluble derivatives such as phenothiazine derivatives can be titrated with satisfactory accuracy and precision by sodium hydroxide despite their high pK(a) values. Likewise barbiturate salts can be titrated by hydrochloric acid. In the case of some salts, the methodology may permit the sequential titration of the ion and counter ion. Copyright 2002 Elsevier Science B.V.

Psychiatry in the U.S. Army: Lessons for Community Psychiatry

DTIC Science & Technology

2005-01-01

narcosynthesis and hypnosis may still be useful techniques in treating acute reactions in which amnesia is present and in treating some refractory PTSD...residency under Army auspices) also required instruction in combat psychiatry and was introduced to the techniques of hypnosis and barbiturate interviews. As...manifestations and prevalence of gain in illness, brief directive methods of psychotherapy, and the use of hypnosis and barbiturate interviews as

Cyanogenic glycosides in plant-based foods available in New Zealand.

PubMed

Cressey, Peter; Saunders, Darren; Goodman, Janet

2013-01-01

Cyanogenic glycosides occur in a wide range of plant species. The potential toxicity of cyanogenic glycosides arises from enzymatic degradation to produce hydrogen cyanide, which may result in acute cyanide poisoning and has also been implicated in the aetiology of several chronic diseases. One hundred retail foods were sampled and analysed for the presence of total hydrocyanic acid using an acid hydrolysis-isonicotinic/barbituric acid colourimetric method. Food samples included cassava, bamboo shoots, almonds and almond products, pome fruit products, flaxseed/linseed, stone fruit products, lima beans, and various seeds and miscellaneous products, including taro leaves, passion fruit, spinach and canned stuffed vine leaves. The concentrations of total hydrocyanic acid (the hydrocyanic acid equivalents of all cyanogenic compounds) found were consistent with or lower than concentrations reported in the scientific literature. Linseed/flaxseed contained the highest concentrations of total hydrocyanic acid of any of the analysed foods (91-178 mg kg(-1)). Linseed-containing breads were found to contain total hydrocyanic acid at concentrations expected from their linseed content, indicating little impact of processing on the total hydrocyanic acid content. Simulation modelling was used to assess the risk due to the total hydrocyanic acid in fruit juice and linseed-containing bread. 

Study of orotidine 5'-monophosphate decarboxylase in complex with the top three OMP, BMP, and PMP ligands by molecular dynamics simulation.

PubMed

Jamshidi, Shirin; Jalili, Seifollah; Rafii-Tabar, Hashem

2015-01-01

Catalytic mechanism of orotidine 5'-monophosphate decarboxylase (OMPDC), one of the nature most proficient enzymes which provides large rate enhancement, has not been fully understood yet. A series of 30 ns molecular dynamics (MD) simulations were run on X-ray structure of the OMPDC from Saccharomyces cerevisiae in its free form as well as in complex with different ligands, namely 1-(5'-phospho-D-ribofuranosyl) barbituric acid (BMP), orotidine 5'-monophosphate (OMP), and 6-phosphonouridine 5'-monophosphate (PMP). The importance of this biological system is justified both by its high rate enhancement and its potential use as a target in chemotherapy. This work focuses on comparing two physicochemical states of the enzyme (protonated and deprotonated Asp91) and three ligands (substrate OMP, inhibitor, and transition state analog BMP and substrate analog PMP). Detailed analysis of the active site geometry and its interactions is properly put in context by extensive comparison with relevant experimental works. Our overall results show that in terms of hydrogen bond occupancy, electrostatic interactions, dihedral angles, active site configuration, and movement of loops, notable differences among different complexes are observed. Comparison of the results obtained from these simulations provides some detailed structural data for the complexes, the enzyme, and the ligands, as well as useful insights into the inhibition mechanism of the OMPDC enzyme. Furthermore, these simulations are applied to clarify the ambiguous mechanism of the OMPDC enzyme, and imply that the substrate destabilization and transition state stabilization contribute to the mechanism of action of the most proficient enzyme, OMPDC.

Barbiturate euthanasia solution-induced tissue artifact in nonhuman primates.

PubMed

Grieves, J L; Dick, E J; Schlabritz-Loutsevich, N E; Butler, S D; Leland, M M; Price, S E; Schmidt, C R; Nathanielsz, P W; Hubbard, G B

2008-06-01

Barbiturate euthanasia solutions are a humane and approved means of euthanasia. Overdosing causes significant tissue damage in a variety of laboratory animals. One hundred seventeen non-human primates (NHP) representing 7 species including 12 fetuses euthanized for humane and research reasons by various vascular routes with Euthasol, Sodium Pentobarbital, Fatal Plus, Beuthanasia D, or Euthanasia 5 were evaluated for euthanasia-induced tissue damage. Lungs and livers were histologically graded for hemolysis, vascular damage, edema, and necrosis. Severity of tissue damage was analyzed for differences on the basis of agent, age, sex, dose, and injection route. Severity of tissue damage was directly related to dose and the intracardiac injection route, but did not differ by species, sex, and agent used. When the recommended dose of agent was used, tissue damage was generally reduced, minimal, or undetectable. Barbiturate-induced artifacts in NHPs are essentially the same as in other laboratory species.

Piracetam and TRH analogues antagonise inhibition by barbiturates, diazepam, melatonin and galanin of human erythrocyte D-glucose transport

PubMed Central

Naftalin, Richard J; Cunningham, Philip; Afzal-Ahmed, Iram

2004-01-01

Nootropic drugs increase glucose uptake into anaesthetised brain and into Alzheimer's diseased brain. Thyrotropin-releasing hormone, TRH, which has a chemical structure similar to nootropics increases cerebellar uptake of glucose in murine rolling ataxia. This paper shows that nootropic drugs like piracetam (2-oxo 1 pyrrolidine acetamide) and levetiracetam and neuropeptides like TRH antagonise the inhibition of glucose transport by barbiturates, diazepam, melatonin and endogenous neuropeptide galanin in human erythrocytes in vitro. The potencies of nootropic drugs in opposing scopolamine-induced memory loss correlate with their potencies in antagonising pentobarbital inhibition of erythrocyte glucose transport in vitro (P<0.01). Less potent nootropics, D-levetiracetam and D-pyroglutamate, have higher antagonist Ki's against pentobarbital inhibition of glucose transport than more potent L-stereoisomers (P<0.001). Piracetam and TRH have no direct effects on net glucose transport, but competitively antagonise hypnotic drug inhibition of glucose transport. Other nootropics, like aniracetam and levetiracetam, while antagonising pentobarbital action, also inhibit glucose transport. Analeptics like bemigride and methamphetamine are more potent inhibitors of glucose transport than antagonists of hypnotic action on glucose transport. There are similarities between amino-acid sequences in human glucose transport protein isoform 1 (GLUT1) and the benzodiazepine-binding domains of GABAA (gamma amino butyric acid) receptor subunits. Mapped on a 3D template of GLUT1, these homologies suggest that the site of diazepam and piracetam interaction is a pocket outside the central hydrophilic pore region. Nootropic pyrrolidone antagonism of hypnotic drug inhibition of glucose transport in vitro may be an analogue of TRH antagonism of galanin-induced narcosis. PMID:15148255

[The clinico-epidemiological premises for antioxidant prevention and treatment in chronic myocardial infarct].

PubMed

Azoicăi, D; Mitu, F; Iacobovici, A; Pavel, M; Jerca, L; Ungureanu, D; Popovici, I; Cojocaru, M; Ivan, A; Gheorghiţă, N

1996-01-01

The improvement of therapeutic and recoverable proceeding to chronic myocardial infarction (IMC) imposes a complex epidemiological estimation of the global cardiovascular risk, of their clinical and biological status. The retrospective evaluation of the risk factors (RF) by epidemiological methods, in 38 hospitalized prevalence of both constitutional and behavioral factors, and the quantification of the risk state, according to graph Euro 194, has pointed on the fact that 50% of IMC cases have presented a global risk of 10-20%. That justified the application of a preventive conduct in order to continually neutralize the associates FR. The biochemical determinations have allowed to frame the dyslipidemic patients, according to the ARCOL classification in the classes D (29.2%), E (25.0%) and B (20.8%) with direct implication in the adopted therapy. The colorimetric dozing with thyo-barbituric acid of the malonly dialdehyde (MAD) each is a product of the lipidic peroxidation, as well as the interpreting or correlation of the registered values with an evolutive clinic stage, and with the existence of some existing diseases (diabetes, chronic hepatitis etc.) along with signification of other dismethabolical parameters (cholesterol, triglycerides, LDLc, apoB) have confirmed the necessity of a complex therapy, including an antioxidative treatment, having the role to directly inhibit or exclude the free radicals resulted after the oxidative stress of the infarct.

[Development and application of electroanalytical methods in biomedical fields].

PubMed

Kusu, Fumiyo

2015-01-01

To summarize our electroanalytical research in the biomedical field over the past 43 years, this review describes studies on specular reflection measurement, redox potential determination, amperometric acid sensing, HPLC with electrochemical detection, and potential oscillation across a liquid membrane. The specular reflection method was used for clarifying the adsorption of neurotransmitters and their related drugs onto a gold electrode and the interaction between dental alloys and compound iodine glycerin. A voltammetric screening test using a redox potential for the antioxidative effect of flavonoids was proposed. Amperometric acid sensing based on the measurement of the reduction prepeak current of 2-methyl-1,4-naphthoquinone (VK3) or 3,5-di-tert-buty1-1,2-benzoquinone (DBBQ) was applied to determine acid values of fats and oils, titrable acidity of coffee, and enzyme activity of lipase, free fatty acids (FFAs) in serum, short-chain fatty acids in feces, etc. The electrode reactions of phenothiazines, catechins, and cholesterol were applied to biomedical analysis using HPLC with electrochemical detection. A three-channel electrochemical detection system was utilized for the sensitive determination of redox compounds in Chinese herbal medicines. The behavior of barbituric acid derivatives was examined based on potential oscillation measurements.

Actions of insecticides on the insect GABA receptor complex

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bermudez, I.; Hawkins, C.A.; Taylor, A.M.

1991-01-01

The actions of insecticides on the insect gamma-aminobutyric acid (GABA) receptor were investigated using (35S)t-butylbicyclophosphorothionate (( 35S)TBPS) binding and voltage-clamp techniques. Specific binding of (35S)TBPS to a membrane homogenate derived from the brain of Locusta migratoria locusts is characterised by a Kd value of 79.3 {plus minus} 2.9 nM and a Bmax value of 1770 {plus minus} 40 fmol/mg protein. (35S)TBPS binding is inhibited by mM concentrations of barbiturates and benzodiazepines. In contrast dieldrin, ivermectin, lindane, picrotoxin and TBPS are inhibitors of (35S)TBPS binding at the nanomolar range. Bicuculline, baclofen and pyrethroid insecticides have no effect on (35S)TBPS binding. Thesemore » results are similar to those obtained in electrophysiological studies of the current elicited by GABA in both Locusta and Periplaneta americana central neurones. Noise analysis of the effects of lindane, TBPS, dieldrin and picrotoxin on the cockroach GABA responses reveals that these compounds decrease the variance of the GABA-induced current but have no effect on its mean open time. All these compounds, with the exception of dieldrin, significantly decrease the conductance of GABA-evoked single current.« less

Pharmacological Protection of the Retina against Damaging Laser Exposures: A Feasibility Study

DTIC Science & Technology

1988-09-01

subsequently administered through this route. Because rabbits can easily be lethally overdosed with barbiturates, surgical plane anesthesia was achieved by...adequately anesthetized. After removal of the second eye, the rabbit was euthanatized by barbiturate overdose . The eye was excised from the rabbit as quickly...Component mq/L uM L-glutamine 73 500 taurine 0.75 6 choline Cl 0.6 4.3 myo-inositol 27 150 Na pyruvate 22 200 ascorbate 18 100 glucose 1800 10,000

Spontaneous abortion and the prophylactic effect of folic acid supplementation in epileptic women undergoing antiepileptic therapy.

PubMed

Pittschieler, Sabine; Brezinka, Christoph; Jahn, Beate; Trinka, Eugen; Unterberger, Iris; Dobesberger, Judith; Walser, Gerald; Auckenthaler, Andrea; Embacher, Norbert; Bauer, Gerhard; Luef, Gerhard

2008-12-01

Antiepileptic drugs (AEDs) like phenytoin (PHE), carbamazepine (CBZ), barbiturates and valproic acid (VPA) interfere with folic acid absorption and metabolism, which in turn can be the cause of adverse pregnancy outcome. To study the prophylactic effect of folic acid supplementation with regard to spontaneous abortion and preterm delivery (fetal demise after week 20 of gestational age) in pregnant women receiving AED therapy, as well as benefits of most common dosage and preconceptional commencement. Prospective examination of 104 patients, registered in EURAP from 1999-2004 at a single center and a retrospective analysis of data from our epilepsy databank completed with medical records and patients interviews of the Department of Neurology of Innsbruck University Hospital from 1971 to 1999. 388 pregnancies in 244 patients were analyzed. Pregnancies with folic acid supplementation showed significant reduction of spontaneous abortion. With regard to monotherapies, in the group of women taking VPA, supplementation of folic acid had significant benefit. Other examined monotherapies (CBZ, PHE, and PB) known to interfere with folic acid showed no significant results. This study confirms the prophylactic effect of folic acid supplementation on spontaneous abortion. For AED therapy, folic acid supplementation should be part of the therapy of every pregnant epileptic woman, especially for those treated with VPA.

Barbiturates

USGS Publications Warehouse

Thomas, N.J.

1999-01-01

Barbiturate products are commonly used to euthanize domestic animals. The primary active component in euthanasia solutions is sodium pentobarbital, but some products also contain other minor ingredients (Fig. 48.1).Euthanasia solutions are generally injected intravenously in domestic animals; therefore, after death, the solutions will be most concentrated in the blood and the highly vascularized organs, such as the liver or spleen, of the euthanized animal.Euthanized carcasses that are available as carrion pose a hazard to scavenging birds and mammals. Large domestic animal carcasses, such as horses, that are not used for food or rendering but that are sufficiently valuable (monetarily or psychologically) to warrant veterinary services and euthanasia drugs are the most common sources of barbiturate poisoning in scavengers. In one instance in British Columbia, a single cow carcass was responsible for poisoning 29 bald eagles.Circumstances that interfere with burial, such as frozen winter soil or bulky carcasses, result in euthanized carcasses being available for scavenger species. This problem could increase in the future if more stringent air-quality standards restrict carcass incineration.

Postulated deficiency of hepatic heme and repair by hematin infusions in the "inducible" hepatic porphyrias.

PubMed Central

Watson, C J; Pierach, C A; Bossenmaier, I; Cardinal, R

1977-01-01

There is compelling, indirect evidence of hepatic heme deficiency due primarily to the respective genetic errors of the three inducible hepatic porphyrias, acute intermittent porphyria, porphyria variegata, and hereditary coproporphyria. The induction is enhanced by exogenous inducers such as barbiturate, estrogens and other "porphyrogenic" chemicals and factors, including glucose deprivation. The newer knowledge of the induction of delta-aminolevulinic acid synthetase [delta-aminolevulinate synthase; succinyl--CoA:glycine C-succinyltransferase (decarboxylating), EC 2.3.1.37] in relation to inadequate heme, and repression by heme, stimulated early trials of hematin infusions to overcome the acute relapse in the foregoing inducible porphyrias. Recently this experience has been considerably expanded, 143 infusions of hematin having been given in 22 cases. Studies of the effect on the serum concentrations of delta-aminolevulinic acid and porphobilinogen have shown a highly significant decline, often to 0, especially of delta-aminolevulinic acid. A distinct relationship to the clinical severity of the attack has been evident in the frequency and magnitude of decline of serum delta-aminolevulinic acid and porphobilinogen. This was regularly associated with objective clinical improvement. PMID:266732

Intermediates of Krebs cycle correct the depression of the whole body oxygen consumption and lethal cooling in barbiturate poisoning in rat.

PubMed

Ivnitsky, Jury Ju; Schäfer, Timur V; Malakhovsky, Vladimir N; Rejniuk, Vladimir L

2004-10-01

Rats poisoned with one LD50 of thiopental or amytal are shown to increase oxygen consumption when intraperitoneally given sucinate, malate, citrate, alpha-ketoglutarate, dimethylsuccinate or glutamate (the Krebs cycle intermediates or their precursors) but not when given glucose, pyruvate, acetate, benzoate or nicotinate (energy substrates of other metabolic stages etc). Survival was increased with succinate or malate from control groups, which ranged from 30-83% to 87-100%. These effects were unrelated to respiratory depression or hypoxia as judged by little or no effect of succinate on ventilation indices and by the lack of effect of oxygen administration. Body cooling of comatose rats at ambient temperature approximately 19 degrees C became slower with succinate, the rate of cooling correlated well with oxygen consumption decrease. Succinate had no potency to modify oxygen consumption and body temperature in intact rats. A condition for antidote effect of the Krebs intermediate was sufficiently high dosage (5 mmol/kg), further dose increase made no odds. Repeated dosing of succinate had more marked protective effect, than a single one, to oxygen consumption and tended to promote the attenuation of lethal effect of barbiturates. These data suggest that suppression of whole body oxygen consumption with barbiturate overdose could be an important contributor to both body cooling and mortality. Intermediates of Krebs cycle, not only succinate, may have a pronounced therapeutic effect under the proper treatment regimen. Availability of Krebs cycle intermediates may be a limiting factor for the whole body oxygen consumption in barbiturate coma, its role in brain needs further elucidation.

Targeted deletion of the GABRA2 gene encoding alpha2-subunits of GABA(A) receptors facilitates performance of a conditioned emotional response, and abolishes anxiolytic effects of benzodiazepines and barbiturates.

PubMed

Dixon, C I; Rosahl, T W; Stephens, D N

2008-07-01

Mice with point-mutated alpha2 GABA(A) receptor subunits (rendering them diazepam insensitive) are resistant to the anxiolytic-like effects of benzodiazepines (BZs) in the conditioned emotional response (CER) test, but show normal anxiolytic effects of a barbiturate. We investigated the consequence of deleting the alpha2-subunit on acquisition of the CER with increasing intensity of footshock, and on the anxiolytic efficacy of a benzodiazepine, diazepam, and a barbiturate, pentobarbital. alpha2 knockout (KO) and wildtype (WT) mice were trained in a conditioned emotional response (CER) task, in which lever pressing for food on a variable interval (VI) schedule was suppressed during the presentation of a compound light/tone conditioned stimulus (CS+) that predicted footshock. The ability of diazepam and of pentobarbital to reduce suppression during the CS+ was interpreted as an anxiolytic response. There were no differences between the genotypes in shock sensitivity, as assessed by their flinch responses to increasing levels of shock. However, alpha2 KO mice showed a greater suppression of lever pressing than WT littermates in the presence of a compound cue signalling footshock. Diazepam (0, 0.5, 1 and 2 mg/kg) induced a dose-dependent anxiolytic-like effect in WT mice but no such effect was seen in KO mice. Similarly, although pentobarbital (20 mg/kg) reduced the ability of the CS+ to reduce lever pressing rates in WT mice, this effect was not seen in the KO. These findings suggest that alpha2-containing GABA(A) receptors mediate the anxiolytic effects of barbiturates, as well as benzodiazepines, and that they may be involved in neuronal circuits underlying conditioned anxiety.

Associations of Adverse Clinical Course and Ingested Substances among Patients with Deliberate Drug Poisoning: A Cohort Study from an Intensive Care Unit in Japan.

PubMed

Ichikura, Kanako; Okumura, Yasuyuki; Takeuchi, Takashi

2016-01-01

Some patients with deliberate drug poisoning subsequently have an adverse clinical course. The present study aimed to examine whether the type of drugs ingested and psychiatric diagnoses were related to an adverse clinical course. We conducted a cohort study of patients with deliberate drug poisoning admitted to the intensive care unit of a university hospital located in Tokyo, Japan, between September 2006 and June 2013. Intensive care unit (ICU) stay of ≥4 days was used as a primary outcome measure, while the incidence of aspiration pneumonitis was used as a secondary outcome measure. Ingested substances and psychiatric diagnoses were used as explanatory variables. Of the 676 patients with deliberate drug poisoning, 88% had a history of psychiatric treatment and 82% had ingested psychotropic drugs. Chlorpromazine-promethazine-phenobarbital combination drug (Vegetamin®) ranked fifth among the most frequently ingested substances in cases of deliberate drug poisoning and had the highest incidence of prolonged ICU stay (20%) and aspiration pneumonitis (29%). The top three major classes consisted of benzodiazepines (79%), new-generation antidepressants (25%), and barbiturates/non-barbiturates (23%). Barbiturate overdose was independently associated with increased odds of both prolonged ICU stay (8% vs. 17%; odds ratio [OR], 2.97; 95% confidence interval [CI], 1.60-5.55) and aspiration pneumonitis (8% vs. 24%; OR, 3.83; 95% CI, 2.18-6.79) relative to those associated with overdose of only other sedative-hypnotics (i.e., benzodiazepines). These results suggest that judicious prescribing of barbiturates by psychiatrists could reduce the risk of an adverse clinical course when a patient attempts an overdose.

A new synthetic approach to functionalize pyrimido[4,5-b]quinoline-2,4(1H,3H)-diones via a three-component one-pot reaction.

PubMed

Aknin, Karen; Desbène-Finck, Stéphanie; Helissey, Philippe; Giorgi-Renault, Sylviane

2010-02-01

Functionalized pyrimido[4,5-b]quinoline-2,4 (1H,3H)-diones were synthesized by a three-component one-pot reaction involving barbituric acid, aldehydes, and anilines. The use of commercially available anilines allowed the facile syntheses of pyrimido[4,5-b]quinolinediones substituted in all the positions on the benzene ring with electron donor or electron withdrawing groups. This straightforward method circumvents the preparation of unstable substituted 2-aminobenzaldehydes that limits the scope of previously described syntheses. Furthermore, access to the 5-substituted derivatives is now also possible starting from aliphatic or aromatic aldehydes. Our strategy and methodology offer significant and practical improvements over other methodologies.

In Silico Discovery of Novel Potent Antioxidants on the Basis of Pulvinic Acid and Coumarine Derivatives and Their Experimental Evaluation

PubMed Central

Martinčič, Rok; Mravljak, Janez; Švajger, Urban; Perdih, Andrej; Anderluh, Marko; Novič, Marjana

2015-01-01

A pigment from the edible mushroom Xerocomus badius norbadione A, which is a natural derivative of pulvinic acid, was found to possess antioxidant properties. Since the pulvinic acid represents a novel antioxidant scaffold, several other derivatives were recently synthetized and evaluated experimentally, along with some structurally related coumarine derivatives. The obtained data formed the basis for the construction of several quantitative structure-activity and pharmacophore models, which were employed in the virtual screening experiments of compound libraries and for the prediction of their antioxidant activity, with the goal of discovering novel compounds possessing antioxidant properties. A final prioritization list of 21 novel compounds alongside 8 established antioxidant compounds was created for their experimental evaluation, consisting of the DPPH assay, 2-deoxyribose assay, β-carotene bleaching assay and the cellular antioxidant activity assay. Ten novel compounds from the tetronic acid and barbituric acid chemical classes displayed promising antioxidant activity in at least one of the used assays, that is comparable to or even better than some standard antioxidants. Compounds 5, 7 and 9 displayed good activity in all the assays, and were furthermore effective preventers of oxidative stress in human peripheral blood mononuclear cells, which are promising features for the potential therapeutic use of such compounds. PMID:26474393

Withdrawal strategies for outpatients

PubMed Central

Mezciems, Edgar

1996-01-01

This article discusses outpatient withdrawal strategies for patients addicted to alcohol, benzodiazepines, barbiturates, and opiates and describes some practical ways to support recovery. PMID:8828877

Daily isoflurane exposure increases barbiturate insensitivity in medullary respiratory and cortical neurons via expression of ε-subunit containing GABA ARs.

PubMed

Hengen, Keith B; Nelson, Nathan R; Stang, Kyle M; Johnson, Stephen M; Smith, Stephanie M; Watters, Jyoti J; Mitchell, Gordon S; Behan, Mary

2015-01-01

The parameters governing GABAA receptor subtype expression patterns are not well understood, although significant shifts in subunit expression may support key physiological events. For example, the respiratory control network in pregnant rats becomes relatively insensitive to barbiturates due to increased expression of ε-subunit-containing GABAARs in the ventral respiratory column. We hypothesized that this plasticity may be a compensatory response to a chronic increase in inhibitory tone caused by increased central neurosteroid levels. Thus, we tested whether increased inhibitory tone was sufficient to induce ε-subunit upregulation on respiratory and cortical neurons in adult rats. Chronic intermittent increases in inhibitory tone in male and female rats was induced via daily 5-min exposures to 3% isoflurane. After 7d of treatment, phrenic burst frequency was less sensitive to barbiturate in isoflurane-treated male and female rats in vivo. Neurons in the ventral respiratory group and cortex were less sensitive to pentobarbital in vitro following 7d and 30d of intermittent isoflurane-exposure in both male and female rats. The pentobarbital insensitivity in 7d isoflurane-treated rats was reversible after another 7d. We hypothesize that increased inhibitory tone in the respiratory control network and cortex causes a compensatory increase in ε-subunit-containing GABAARs.

Effects of polychlorinated biphenyls and nutritional restriction on barbituate-induced sleeping times and selected blood characteristics in raccoons (Procyon lotor)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Montz, W.E.; Card, W.C.; Kirkpatrick, R.L.

1982-05-01

Hepatic microsomal enzyme activity was induced in wild-trapped raccoons (Procyon lotor) and selected blood characteristics were measured in an effort to detect responses due to PCB ingestion, nutritional restriction, and their interactions. Barbiturate-induced sleeping times were used as an index of hepatic microsomal activity because they have been used reliably by other workers. Blood characteristics examined in the study were nonesterified fatty acids (NEFA), cholesterol, and three ketone bodies (D-(-)-3-hydroxybutyrate, acetoacetate, and acetone). Results show a reduction in sleeping times, elevated NEFA and D-(-)-3-hydroxybutyrate concentrations, and lower cholesterol concentrations in PCB-treated groups. A highly significant interaction between PCB treatment andmore » nutritional restriction was observed in acetoacetate concentrations. (JMT)« less

Synergism of isothermal regimen and sodium succinate in experimental therapy of barbiturate coma.

PubMed

Reinyuk, V L; Shefer, T V; Ivnitskii, Yu Yu

2006-07-01

In rats with experimental thiopental coma rectal temperature decreased by 9.4 degrees C, oxygen consumption 5-fold, and arteriovenous Po(2)gradient decreased 2-fold within 3 h; CO(2)accumulated in the blood and mixed type acidosis developed. Administration of sodium succinate under these conditions increased arteriovenous Po(2)gradient and reduced manifestations of metabolic acidosis. Maintenance of normal body temperature (warming) corrected primarily manifestations of respiratory acidosis. Each therapeutic agent reduced inhibition of O(2)consumption by 1/4; animal survival tended to increase from 42 to 50%. Combined use of these treatments potentiated the antiacidotic effect and increased survival to 92%. The authors conclude that hypothermia inhibits the therapeutic effect of succinate in barbiturate coma.

Molecular structure and spectroscopic investigations combined with hypoglycemic/anticancer and docking studies of a new barbituric acid derivative

NASA Astrophysics Data System (ADS)

Barakat, Assem; Soliman, Saied M.; Elshaier, Yaseen A. M. M.; Ali, M.; Al-Majid, Abdullah Mohammed; Ghabbour, Hazem A.

2017-04-01

The one-pot synthesis reaction of barbituric acid derivative, 1,3-cyclohexandione, and 4-fluorobenzaldehyde in water mediated by NHEt2 as base afforded 4 with excellent yield. The synthesized compound was characterized by spectrophotometric tools as well as X-ray single crystal diffraction technique. The stability of the nine possible isomers of the synthesized compound was studied using the B3LYP method and 6-31G(d,p) basis set. The electronic and spectroscopic properties of the most stable isomer were predicted. The UV-Vis absorption spectrum displayed two bands at 203 and 257 nm in the solvent chloroform. The latter was calculated at 235.6 nm (f = 0.1995) in the gas phase due to H-2→L (42%) and H-1→L+2 (14%) excitations. In solution, using chloroform as a solvent, a slight bathochromic shift to 237.6 nm with an increase in the absorption intensity (f = 0.2898) was predicted. The molecular orbital energy level diagram of this transition band was characterized mainly by π-π* transitions. The 13C and 1H NMR chemical shifts correlated well with the experimental data. The correlations had higher correlation coefficients (R2) when solvent effects were considered. The atomic charges were calculated using natural population analysis and the charged regions were presented using a molecular electrostatic potential (MEP) map. The synthesized compound was examined as a hypoglycemic agent via inhibition of α-glucosidase and β-glucuronidase enzymes. Its inhibitory activity against α-glucosidase was 10 times greater than the inhibitory activity of the standard drug acarbose (IC50 77.9 ± 0.3 μM and 840 ± 1.73 μM, respectively). Moreover, the target compound was evaluated for anticancer activity against MCF-7, H460, 3T3, and Hela cell lines. It demonstrated inhibitory activity against the MCF-7 and H460 cell lines with IC50 5.80 ± 0.12 and 19.6 ± 0.5 μM, respectively, in comparison to doxorubicin. The docking study was performed using the OpenEye program.

An unusual case of relay pentobarbital toxicosis in a dog.

PubMed

Bischoff, Karyn; Jaeger, Robin; Ebel, Joseph G

2011-09-01

Sodium pentobarbital and phenytoin are common constituents of veterinary euthanasia solutions in the United States. Relay, or secondary, barbiturate toxicosis has been reported in carnivorous animals that have fed from the carcasses of euthanized livestock. This case report presents barbiturate toxicosis in a dog. A 2-year-old female spayed Australian shepherd presented comatose 2 h after ingesting an unknown substance on the beach. The material was retrieved from the stomach by gastric lavage and visually identified as fish or other animal tissue. The dog recovered with symptomatic and supportive therapy and was released on the third day of hospitalization. Tissue found on the beach near where the dog walked and a urine sample from the dog were analyzed by gas chromatography/mass spectrometry. Both samples were positive for pentobarbital and phenytoin. The tissue was consistent with mammalian blubber based on gross and histological examination. Three weeks previously, a juvenile humpback whale had stranded on the beach where the dog had ingested the unknown substance. The whale had been euthanized with a barbiturate solution, necropsied, and removed from the beach. It was not definitively determined that the pentobarbital-containing blubber ingested by the dog was from the euthanized whale, but that was the most likely source. Although attempts were made to remove the whale's remains from the beach, practical considerations made complete removal challenging, if not impossible.

Evidence for involvement of the astrocytic benzodiazepine receptor in the mechanism of action of convulsant and anticonvulsant drugs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bender, A.S.; Hertz, L.

1988-01-01

The anticonvulsant drugs carbamazepine, phenobarbital, trimethadione, valproic acid and ethosuximide at pharmacologically relevant concentrations inhibit (/sup 3/H)diazepam binding to astrocytes in primary cultures but have much less effect on a corresponding preparation of neurons. Phenytoin as well as pentobarbital (which is not used chronically as an anticonvulsant) are equipotent in the two cell types. The convulsants picrotoxinin and pentylenetetrazol, the convulsant benzodiazepine RO 5-3663 and the two convulsant barbiturates DMBB and CHEB similarly inhibit diazepam binding to astrocytes but have little effect on neurons. On the basis of these findings it is suggested that these convulsants and anticonvulsants owe atmore » least part of their effect to an interaction with the astrocytic benzodiazepine receptor, perhaps by interference with a calcium channel.« less

The role of regional nerve block anesthesia for carotid endarterectomy: an experimental comparison with previous series with the use of general anesthesia and barbiturates for cerebral protection.

PubMed

Agrifoglio, G; Agus, G B; Bonalumi, F; Costantini, A; Carlesi, R

1987-01-01

A retrospective analysis was performed on a consecutive series of 60 cases divided into two groups given carotid endarterectomy (C.E.) for atherosclerotic disease. In the first group general anesthesia and barbiturate cerebral protection were employed; in group two, loco-regional anesthesia. Indications and risk factors were similar in the two groups; the surgical procedure was identical. The differences in the results are reported and factors contributing to cerebral protection or reduction in the risk of stroke are analyzed. The analysis indicates that loco-regional anesthesia for C.E. is a reliable method for detecting cerebral ischemia and guaranteeing cerebral protection by means of a temporary shunt when strictly necessary.

Identifying Drugs

MedlinePlus

... Phencyclidine) Peyote and Mescaline Psilocybin Rohypnol Salvia Divinorum Spice/ K2, Synthetic Marijuana Steroids U-47700 Amphetamines Barbiturates ... Phencyclidine) Peyote and Mescaline Psilocybin Rohypnol Salvia Divinorum Spice/ K2, Synthetic Marijuana Steroids U-47700 Aerosol cans ...

Bibliography [On Drugs].

ERIC Educational Resources Information Center

National Association of Student Personnel Administrators, Detroit, MI.

A bibliography of materials on drugs is presented. The book and paper back entries are annotated. Selected technical references are listed under these major findings: (1) dependency, (2) barbiturates, (3) amphetamines, and (4) general pharmacology. (PS)

41 CFR Appendix to Part 102 - 74-Rules and Regulations Governing Conduct on Federal Property

Code of Federal Regulations, 2012 CFR

2012-01-01

... from— (a) Being under the influence, using or possessing any narcotic drugs, hallucinogens, marijuana... alcoholic beverages, narcotic drugs, hallucinogens, marijuana, barbiturates, or amphetamines. Alcoholic...

41 CFR Appendix to Part 102 - 74-Rules and Regulations Governing Conduct on Federal Property

Code of Federal Regulations, 2010 CFR

2010-07-01

... from— (a) Being under the influence, using or possessing any narcotic drugs, hallucinogens, marijuana... alcoholic beverages, narcotic drugs, hallucinogens, marijuana, barbiturates, or amphetamines. Alcoholic...

41 CFR Appendix to Part 102 - 74-Rules and Regulations Governing Conduct on Federal Property

Code of Federal Regulations, 2014 CFR

2014-01-01

... from— (a) Being under the influence, using or possessing any narcotic drugs, hallucinogens, marijuana... alcoholic beverages, narcotic drugs, hallucinogens, marijuana, barbiturates, or amphetamines. Alcoholic...

41 CFR Appendix to Part 102 - 74-Rules and Regulations Governing Conduct on Federal Property

Code of Federal Regulations, 2013 CFR

2013-07-01

... from— (a) Being under the influence, using or possessing any narcotic drugs, hallucinogens, marijuana... alcoholic beverages, narcotic drugs, hallucinogens, marijuana, barbiturates, or amphetamines. Alcoholic...

41 CFR Appendix to Part 102 - 74-Rules and Regulations Governing Conduct on Federal Property

Code of Federal Regulations, 2011 CFR

2011-01-01

... from— (a) Being under the influence, using or possessing any narcotic drugs, hallucinogens, marijuana... alcoholic beverages, narcotic drugs, hallucinogens, marijuana, barbiturates, or amphetamines. Alcoholic...

Citrate-capped superparamagnetic iron oxide (Fe3O4-CA) nanocatalyst for synthesis of pyrimidine derivative compound as antioxidative agent

NASA Astrophysics Data System (ADS)

Cahyana, A. H.; Pratiwi, D.; Ardiansah, B.

2017-04-01

The development of a recyclable catalyst based on magnetic nanoparticles has attracted an increasing interest as the emerging application in the heterogeneous catalyst field. Superparamagnetic iron oxide nanoparticle with citric acid as capping agent was successfully obtained from iron (III) chloride solution via two steps synthesis. The first step involving the formation of magnetite nanoparticle by bioreduction using Sargassum Sp, then its surface was modified by adding citric acid solution in the second step. The structural, surface morphology and magnetic properties of the nanocatalyst were investigated by various instrumentations such as scanning electron microscope with energy dispersive (SEM-EDS), and particle size analyser (PSA). Fe3O4-CA was then applied as reusable catalyst for Knoevenagel condensation of barbituric acid and cinnamaldehyde to produce (E)-5-(3-phenylallylidene)pyrimidine-2,4,6(1H,3H,5H)-trione. The optimum condition of this reaction was achieved by using 7.5% mole of catalyst at 50°C for 6 h to give 83% yield. Some spectroscopy techniques such as UV-Vis, FTIR, LC-MS and 1H-NMR were used to confirm the product’s structure. Furthermore, the synthesized compound has an attractive antioxidant activity based on the in-vitro analysis using DPPH method.

Influence of chronic barbiturate administration on sleep apnea after hypersomnia presentation: case study.

PubMed Central

Takhar, J; Bishop, J

2000-01-01

When sleepiness is excessive, undesirable, inappropriate or unexplained, it often indicates a clinical disorder that is generically termed hypersomnia. One of the leading causes of hypersomnia is sleep apnea. We present the case of a 44-year-old woman with a history of bipolar spectrum disorder and epilepsy who initially showed evidence of hypersomnia. The hypersomnia settled with changes to her medication, but the patient was subsequently found to have severe obstructive sleep apnea. The relation between the patient's medication and sleep apnea is discussed, and the possible respiratory-suppressant effects of chronic barbiturate treatment are considered. The role of other evoking factors within the context of this case and the mechanisms by which drug interactions and psychotropic treatment may worsen, obscure or perpetuate sleep apnea are also examined. PMID:11022396

Procedure for detecting and confirming pentobarbital residues in dog food by gas chromatography/mass spectrometry.

PubMed

Adam, L A; Reeves, V B

1998-01-01

The method described detects and confirms presence of pentobarbital residues in dry, extruded feeds at concentrations of 5-20 ppb. Dried feed is ground to a uniform powder and shaken overnight in methanol. A portion of the methanolic extract is evaporated, and the residue is reconstituted in phosphate-buffered saline. The aqueous extract is cleaned with a solid-phase extraction cartridge designed to extract barbiturate residues from biological matrixes. Dimethyl sulfoxide, tetramethylammonium hydroxide, and iodomethane are added to derivatize pentobarbital, 1,3-Dimethyl-pentobarbital is then acidified with dilute hydrochloric acid and extracted with isooctane. The organic layer is transferred and evaporated under a stream of nitrogen. The residue is reconstituted in a small volume of ethyl acetate for analysis by gas chromatography/mass spectrometry. The limit of detection is approximately 0.7 ppb. The method was validated with pentobarbital-fortified feed samples containing high concentrations of meat and bone meal.

EFFECTS OF X-IRRADIATION ON THE HEXOBARBITAL METABOLIZING ENZYME SYSTEM OF RAT LIVER MICROSOMES.

DTIC Science & Technology

RADIATION EFFECTS , *ENZYME INHIBITORS, *HYPNOTICS AND SEDATIVES, ENZYMES, BIOSYNTHESIS, METABOLISM, DETOXIFICATION, BARBITURATES, OXIDATION...MICROSOMES, LIVER, REGENERATION(ENGINEERING), EXCISION, SUBLETHAL DOSAGE, TOXICITY , HYPNOSIS, SLEEP, HEAD(ANATOMY), MALES, FEMALES, RATS.

Structural and electronic properties of barbituric acid and melamine-containing ribonucleosides as plausible components of prebiotic RNA: implications for prebiotic self-assembly.

PubMed

Kaur, Sarabjeet; Sharma, Purshotam; Wetmore, Stacey D

2017-11-22

The RNA world hypothesis assumes that RNA was the first informational polymer that originated from prebiotic chemical soup. However, since the reaction of d-ribose with canonical nucleobases (A, C, G and U) fails to yield ribonucleosides (rNs) in substantial amounts, the spontaneous origin of rNs and the subsequent synthesis of RNA remains an unsolved mystery. To this end, it has been suggested that RNA may have evolved from primitive genetic material (preRNA) composed of simpler prebiotic heterocycles that spontaneously form glycosidic bonds with ribose. As an effort toward evaluating this hypothesis, the present study uses density functional theory (DFT) to assess the suitability of barbituric acid (BA) and melamine (MM) to act as prebiotic nucleobases, both of which have recently been shown to spontaneously form a glycosidic bond with ribose and organize into supramolecular assemblies in solution. The significant strength of hydrogen bonds involving BA and MM indicates that such interactions may have played a crucial role in their preferential selection over competing heterocycles that interact solely through stacking interactions from the primordial soup during the early phase of evolution. However, the greater stability of stacked dimers involving BA or MM and the canonical nucleobases compared to those consisting solely of BA and/or MM points towards the possible evolution of intermediate informational polymers consisting of prebiotic and canonical nucleobases, which could have eventually evolved into RNA. Analysis of the associated rNs reveals an anti conformational preference for the biologically-relevant β-anomer of both BA and MM rNs, which will allow complementary WC-like hydrogen bonding that can stabilize preRNA polymers. Large calculated deglycosylation barriers suggest BA rNs containing C-C glycosidic bonds are relevant in challenging prebiotic environments such as volcanic geotherms, while lower barriers indicate the MM rNs containing C-N-C glycosidic linkages may have been more likely synthesized from simple precursors such as urea-ice in icy (polar) regions. Together, our quantum chemical data clarifies the physicochemical interactions and stability of potential prebiotically-relevant constituents of BA and MM polymeric assemblies, and complements information from previous experimental studies to bolster the candidature of these heterocycles as prebiotic nucleobases.

PERTURBATION OF VOLTAGE-SENSITIVE CALCIUM FUNCTION IN PHEOCHROMOCYTOMA CELLS BY VOLATILE ORGANIC SOLVENTS.

EPA Science Inventory

Volatile organic solvents such as toluene (TOL) and trichloroethylene perturb nervous system function and share characteristic effects with other central nervous system depressants such as anesthetic gasses, ethanol, benzodiazepines and barbiturates. Recently, mechanistic studies...

Neurotoxic effects of carambola in rats: the role of oxalate.

PubMed

Chen, Chien-Liang; Chou, Kang-Ju; Wang, Jyh-Seng; Yeh, Jeng-Hsien; Fang, Hua-Chang; Chung, Hsiao-Min

2002-05-01

Carambola (star fruit) has been reported to contain neurotoxins that cause convulsions, hiccups, or death in uremic patients, and prolong barbiturate-induced sleeping time in rats. The constituent responsible for these effects remains uncertain. Carambola contains a large quantity of oxalate, which can induce depression of cerebral function and seizures. This study was conducted to investigate the role of oxalate in carambola toxicity in rats. The effects on barbiturate-induced sleeping time and death caused by intraperitoneal administration of carambola juice were observed in Sprague-Dawley rats. To obtain a dose-dependent response curve and evaluate the lethal dose, rats were treated with serial amounts of pure carambola juice diluted with normal saline in a volume of 1:1. To test the role of oxalate in the neurotoxic effect of carambola, either 5.33 g/kg carambola after oxalate removal or 5.33 g/kg of pure carambola juice diluted with normal saline were administered intraperitoneally, while the control group was given normal saline before pentobarbital injection. The effects of carambola and oxalate-removed carambola on barbiturate-induced sleeping time were compared with those of saline. To assess the lethal effect of oxalate in carambola, we gave rats chemical oxalate at comparable concentrations to the oxalate content of carambola. Carambola juice administration prolonged barbiturate-induced sleeping time in a dose-dependent manner. The sleeping time of rats that received normal saline and 1.33 g/kg, 2.67 g/kg, 5.33 g/kg, and 10.67 g/kg of carambola juice were 66 +/- 16.6, 93.7 +/- 13.4, 113.3 +/- 11.4, 117.5 +/- 29.0, and 172.5 +/- 38.8 minutes, respectively. The three higher-dose groups had longer sleeping times than controls (p < 0.05 or 0.005). This effect was eliminated after the removal of oxalate from carambola juice. Four of eight rats in the 10.67-g/kg group and all rats in the 21.33 g/kg and chemical oxalate groups died after seizure. Lethal doses of carambola juice were rendered harmless by the oxalate removal procedure. Oxalate is a main constituent of carambola neurotoxicity. This finding suggests that patients with carambola intoxication should be treated for oxalate toxicosis.

Metabolic mechanisms of drug-nutrient interactions.

PubMed

Hathcock, J N

1985-01-01

Metabolic mechanisms of nutrition and drug interactions include 1) the effects of diet on drug metabolism and action and 2) the effects of drugs on nutritional processes. The type, amount, and timing of foods consumed influence drug dissolution, absorption, distribution, metabolism, and excretion. High-fat meals enhance the absorption of griseofulvin and some other drugs. Milk and other sources of calcium inhibit absorption of tetracycline. High-fat meals increase plasma concentrations of free fatty acids and thereby displace many drugs from binding sites on plasma albumin. High-protein diets increase the activity of the mixed-function oxidase system and enhance the metabolism of numerous drugs. High-electrolyte intakes increase excretion of lithium and also diminish the action of diuretic agents. Bile acid sequestrants and some laxatives decrease lipid digestion and absorption, as well as absorption of the fat-soluble vitamins. Numerous drugs, including tetracycline and cholestyramine, bind iron and decrease its absorption. Coumarins inhibit the function of vitamin K. Phenobarbital and other anticonvulsants are inducers of cytochrome P-450 and the mixed-function oxidase system. Long-term treatment with these inducers can cause excessive metabolism and deficiency of vitamin D. Prooxidant drugs such as chloroquine, drugs detoxified by conjugation with glutathione, and alcohol can deplete reduced glutathione with consequent effects on amino acid transport and the redox status of cells. Acid-forming foods acidify the urine and increase the loss of alkaline drugs such as the amphetamines. Base-forming drugs increase the loss of acidic drugs such as barbiturates. The range of metabolic interactions of drugs and nutrients includes the full scope of physiological processes to which drugs and nutrients are subject.

44 CFR 15.9 - Alcoholic beverages and narcotics.

Code of Federal Regulations, 2012 CFR

2012-10-01

... beverages, narcotic drugs, hallucinogens, marijuana, barbiturates or amphetamines as defined in Title 21 of... property being under the influence of or using or possessing any narcotic drug, marijuana, hallucinogen... influence of alcoholic beverages; (d) Bringing alcoholic beverages, narcotic drugs, hallucinogens, marijuana...

44 CFR 15.9 - Alcoholic beverages and narcotics.

Code of Federal Regulations, 2014 CFR

2014-10-01

... beverages, narcotic drugs, hallucinogens, marijuana, barbiturates or amphetamines as defined in Title 21 of... property being under the influence of or using or possessing any narcotic drug, marijuana, hallucinogen... influence of alcoholic beverages; (d) Bringing alcoholic beverages, narcotic drugs, hallucinogens, marijuana...

44 CFR 15.9 - Alcoholic beverages and narcotics.

Code of Federal Regulations, 2013 CFR

2013-10-01

... beverages, narcotic drugs, hallucinogens, marijuana, barbiturates or amphetamines as defined in Title 21 of... property being under the influence of or using or possessing any narcotic drug, marijuana, hallucinogen... influence of alcoholic beverages; (d) Bringing alcoholic beverages, narcotic drugs, hallucinogens, marijuana...

44 CFR 15.9 - Alcoholic beverages and narcotics.

Code of Federal Regulations, 2011 CFR

2011-10-01

... beverages, narcotic drugs, hallucinogens, marijuana, barbiturates or amphetamines as defined in Title 21 of... property being under the influence of or using or possessing any narcotic drug, marijuana, hallucinogen... influence of alcoholic beverages; (d) Bringing alcoholic beverages, narcotic drugs, hallucinogens, marijuana...

44 CFR 15.9 - Alcoholic beverages and narcotics.

Code of Federal Regulations, 2010 CFR

2010-10-01

... beverages, narcotic drugs, hallucinogens, marijuana, barbiturates or amphetamines as defined in Title 21 of... property being under the influence of or using or possessing any narcotic drug, marijuana, hallucinogen... influence of alcoholic beverages; (d) Bringing alcoholic beverages, narcotic drugs, hallucinogens, marijuana...

Fast targeted analysis of 132 acidic and neutral drugs and poisons in whole blood using LC-MS/MS.

PubMed

Di Rago, Matthew; Saar, Eva; Rodda, Luke N; Turfus, Sophie; Kotsos, Alex; Gerostamoulos, Dimitri; Drummer, Olaf H

2014-10-01

The aim of this study was to develop an LC-MS/MS based screening technique that covers a broad range of acidic and neutral drugs and poisons by combining a small sample volume and efficient extraction technique with simple automated data processing. After protein precipitation of 100μL of whole blood, 132 common acidic and neutral drugs and poisons including non-steroidal anti-inflammatory drugs, barbiturates, anticonvulsants, antidiabetics, muscle relaxants, diuretics and superwarfarin rodenticides (47 quantitated, 85 reported as detected) were separated using a Shimadzu Prominence HPLC system with a C18 separation column (Kinetex XB-C18, 4.6mm×150mm, 5μm), using gradient elution with a mobile phase of 25mM ammonium acetate buffer (pH 7.5)/acetonitrile. The drugs were detected using an ABSciex(®) API 2000 LC-MS/MS system (ESI+ and -, MRM mode, two transitions per analyte). The method was fully validated in accordance with international guidelines. Quantification data obtained using one-point calibration compared favorably to that using multiple calibrants. The presented LC-MS/MS assay has proven to be applicable for determination of the analytes in blood. The fast and reliable extraction method combined with automated processing gives the opportunity for high throughput and fast turnaround times for forensic and clinical toxicology. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Studies of Circulatory and Metabolic Changes during Ketamine Narcosis,

DTIC Science & Technology

1985-03-13

Braun, U., Hensel, I., Kettler, D., Lohr, B.: The effects of methoxyflurane , halothane, dipiritramide, barbiturate and ketamine on the total oxygen...narcosis caus- ed by ether, halothane, methoxyflurane , ketamine and piritranide, as well as neuroleptanalgesia. Lecture at the XIIth. General Con

Postoperative Cerebral Infarction Risk Factors and Postoperative Management of Pediatric Patients with Moyamoya Disease.

PubMed

Muraoka, Shinsuke; Araki, Yoshio; Kondo, Goro; Kurimoto, Michihiro; Shiba, Yoshiki; Uda, Kenji; Ota, Shinji; Okamoto, Sho; Wakabayashi, Toshihiko

2018-05-01

Although revascularization surgery for patients with moyamoya disease can effectively prevent ischemic events and thus improve the long-term clinical outcome, the incidence of postoperative ischemic complications affects patients' quality of life. This study aimed to clarify the risk factors associated with postoperative ischemic complications and to discuss the appropriate perioperative management. Fifty-eight revascularization operations were performed in 37 children with moyamoya disease. Patients with moyamoya syndrome were excluded from this study. Magnetic resonance imaging was performed within 7 days after surgery. Postoperative cerebral infarction was defined as a diffusion-weighted imaging high-intensity lesion with or without symptoms. We usually use fentanyl and dexmedetomidine as postoperative analgesic and sedative drugs for patients with moyamoya disease. We used barbiturate coma therapy for pediatric patients with moyamoya disease who have all postoperative cerebral infarction risk factors. Postoperative ischemic complications were observed in 10.3% of the children with moyamoya disease (6 of 58). Preoperative cerebral infarctions (P = 0.0005), younger age (P = 0.038), higher Suzuki grade (P = 0.003), and posterior cerebral artery stenosis/occlusion (P = 0.003) were related to postoperative ischemic complications. Postoperative cerebral infarction occurred all pediatric patients using barbiturate coma therapy. The risk factors associated with postoperative ischemic complications for children with moyamoya disease are preoperative infarction, younger age, higher Suzuki grade, and posterior cerebral artery stenosis/occlusion. Barbiturate coma therapy for pediatric patients with moyamoya disease who have the previous risk factors is insufficient for prevention of postoperative cerebral infarction. More studies are needed to identify the appropriate perioperative management. Copyright © 2018 Elsevier Inc. All rights reserved.

Chemical Aspects of General Anesthesia: Part II. Current Practices

ERIC Educational Resources Information Center

Brunsvold, Robert; Ostercamp, Daryl L.

2006-01-01

The basics of balanced general anesthesia developed since 1956 and the update on existing practices of intravenous induction anesthetics and inhalational anesthetics are discussed. Some of the progressive anesthetics discussed are propofol instead of barbiturate such as thiopental or methohexital, inhalational anesthetic halothane,…

[Biperiden abuse as a partial factor in polytoxicomania].

PubMed

Schulte, R M

1988-03-01

We found 16 patients (15%) taking the anticholinergic biperiden because of its psychotropic action, occasionally, rather frequently or regularly, among a subgroup of 120 drug-dependent patients (drugs of the barbiturate and amphetamin types) out of a studied total of 194 imprisoned male addicts. These biperiden abusers suffered without exception from polytoxicomania associated with drug dependence and alcoholism. Most prominent was drug dependence on drugs of the morphine type. We could not prove a case of an isolated "primary" abuse of biperiden. Direct medical prescription was a rather secondary factor in procuring this preparation, in contrast to analgesics, tranquilisers, barbiturates and clomethiazol. Increase of biperiden abuse is due, on the one hand, to a generally noticeable tendency to polytoxicomania, and on the other hand to a change in Federal German drug prescription rules effective 1 August 1986 according to which fenetylline hydrochloride, a sympathomimetic, is now subject to medical prescription. Other centrally acting anticholinergics were unknown among this group of patients and were not abused. The results are discussed on the basis of available literature.

The ketogenic diet as broad-spectrum treatment for super-refractory pediatric status epilepticus: challenges in implementation in the pediatric and neonatal intensive care units.

PubMed

Cobo, Nicole H; Sankar, Raman; Murata, Kristina K; Sewak, Sarika L; Kezele, Michele A; Matsumoto, Joyce H

2015-02-01

Refractory status epilepticus carries significant morbidity and mortality. Recent reports have promoted the use of the ketogenic diet as an effective treatment for refractory status epilepticus. We describe our recent experience with instituting the ketogenic diet for 4 critically ill children in refractory status epilepticus, ranging in age from 9 weeks to 13.5 years after failure of traditional treatment. The ketogenic diet allowed these patients to be weaned off continuous infusions of anesthetics without recurrence of status epilepticus, though delayed ketosis and persistently elevated glucose measurements posed special challenges to effective initiation, and none experienced complete seizure cessation. The ease of sustaining myocardial function with fatty acid energy substrates compares favorably over the myocardial toxicity posed by anesthetic doses of barbiturates and contributes to the safety profile of the ketogenic diet. The ketogenic diet can be implemented successfully and safely for the treatment of refractory status epilepticus in pediatric patients. © The Author(s) 2014.

Shelf Life Prediction for Canned Gudeg using Accelerated Shelf Life Testing (ASLT) Based on Arrhenius Method

NASA Astrophysics Data System (ADS)

Nurhayati, R.; Rahayu NH, E.; Susanto, A.; Khasanah, Y.

2017-04-01

Gudeg is traditional food from Yogyakarta. It is consist of jackfruit, chicken, egg and coconut milk. Gudeg generally have a short shelf life. Canning or commercial sterilization is one way to extend the shelf life of gudeg. This aims of this research is to predict the shelf life of Andrawinaloka canned gudeg with Accelerated Shelf Life Test methods, Arrhenius model. Canned gudeg stored at three different temperature, there are 37, 50 and 60°C for two months. Measuring the number of Thio Barbituric Acid (TBA), as a critical aspect, were tested every 7 days. Arrhenius model approach is done with the equation order 0 and order 1. The analysis showed that the equation of order 0 can be used as an approach to estimating the shelf life of canned gudeg. The storage of Andrawinaloka canned gudeg at 30°C is predicted untill 21 months and 24 months for 25°C.

Toxic nephropathy after low-dose methoxyflurane anesthesia: drug interaction with secobarbital?

PubMed

Churchill, D; Yacoub, J M; Siu, K P; Symes, A; Gault, M H

1976-02-21

Vasopressin-resistant nonoliguric renal insufficiency developed in a 57-year-old man after 2 1/2 hours of low-dose methoxyflurane anesthesia. Secobarbital, 100 mg daily, had been taken for 1 month before. Of 13 patients in whom the influence of methoxyflurane on renal function was being studied, he was the only one to have taken a drug that induces microsomal enzymes. Blood values of methoxyflurane in this patient were lower than group means on all five occasions during anesthesia. Postoperatively his serum inorganic fluoride value reached 114 mumol/l -- more than two standard deviations greater than the group mean. Peak values for serum urea nitrogen, creatinine and uric acid and postvasopressin urine osmolality, and the lowest creatinine clearance in this patient also differed by more than 2 SD from the group mean, and the peak amount of oxalate excreted in his urine was double the group mean. Pretreatment with the barbiturate appears to have altered methoxyflurane metabolism and led to toxic concentrations of metabolites in the blood.

Toxic nephropathy after low-dose methoxyflurane anesthesia: drug interaction with secobarbital?

PubMed Central

Churchill, D.; Yacoub, J. M.; Siu, K. P.; Symes, A.; Gault, M. H.

1976-01-01

Vasopressin-resistant nonoliguric renal insufficiency developed in a 57-year-old man after 2 1/2 hours of low-dose methoxyflurane anesthesia. Secobarbital, 100 mg daily, had been taken for 1 month before. Of 13 patients in whom the influence of methoxyflurane on renal function was being studied, he was the only one to have taken a drug that induces microsomal enzymes. Blood values of methoxyflurane in this patient were lower than group means on all five occasions during anesthesia. Postoperatively his serum inorganic fluoride value reached 114 mumol/l -- more than two standard deviations greater than the group mean. Peak values for serum urea nitrogen, creatinine and uric acid and postvasopressin urine osmolality, and the lowest creatinine clearance in this patient also differed by more than 2 SD from the group mean, and the peak amount of oxalate excreted in his urine was double the group mean. Pretreatment with the barbiturate appears to have altered methoxyflurane metabolism and led to toxic concentrations of metabolites in the blood. PMID:1253070

[Selected Readings for the Professional Working with Drug Related Problems.

ERIC Educational Resources Information Center

Wisconsin Univ., Madison.

A bibliography of selected readings compiled at the University of Wisconsin for the National Drug Education Training Program. These selected readings include information on narcotics, amphetamines, mescaline, psilogybin, hallucinogens, LSD, barbiturates, alcohol, and other stimulants. The intended user of this bibliography is the professional…

29 CFR Appendix A to Subpart T to... - Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions

Code of Federal Regulations, 2012 CFR

2012-07-01

... duration of isolation. History of seizure disorder other than early febrile convulsions. Malignancies... or drug use. Conditions requiring continuous medication for control (e.g., antihistamines, steroids, barbiturates, moodaltering drugs, or insulin). Meniere's disease. Hemoglobinopathies. Obstructive or...

29 CFR Appendix A to Subpart T of... - Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions

Code of Federal Regulations, 2013 CFR

2013-07-01

... duration of isolation. History of seizure disorder other than early febrile convulsions. Malignancies... or drug use. Conditions requiring continuous medication for control (e.g., antihistamines, steroids, barbiturates, moodaltering drugs, or insulin). Meniere's disease. Hemoglobinopathies. Obstructive or...

29 CFR Appendix A to Subpart T to... - Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions

Code of Federal Regulations, 2011 CFR

2011-07-01

... duration of isolation. History of seizure disorder other than early febrile convulsions. Malignancies... or drug use. Conditions requiring continuous medication for control (e.g., antihistamines, steroids, barbiturates, moodaltering drugs, or insulin). Meniere's disease. Hemoglobinopathies. Obstructive or...

29 CFR Appendix A to Subpart T of... - Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions

Code of Federal Regulations, 2014 CFR

2014-07-01

... duration of isolation. History of seizure disorder other than early febrile convulsions. Malignancies... or drug use. Conditions requiring continuous medication for control (e.g., antihistamines, steroids, barbiturates, moodaltering drugs, or insulin). Meniere's disease. Hemoglobinopathies. Obstructive or...

Utah Drop-Out Drug Use Questionnaire.

ERIC Educational Resources Information Center

Governor's Citizen Advisory Committee on Drugs, Salt Lake City, UT.

This questionnaire assesses drug use practices in high school drop-outs. The 79 items (multiple choice or apply/not apply) are concerned with demographic data and use, use history, reasons for use/nonuse, attitudes toward drugs, availability of drugs, and drug information with respect to narcotics, amphetamines, LSD, Marijuana, and barbiturates.…

21 CFR 1301.90 - Employee screening procedures.

Code of Federal Regulations, 2010 CFR

2010-04-01

..., assumed that the following questions will become a part of an employer's comprehensive employee screening program: Question. Within the past five years, have you been convicted of a felony, or within the past two.... Question. In the past three years, have you ever knowingly used any narcotics, amphetamines or barbiturates...

29 CFR Appendix A to Subpart T to... - Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions

Code of Federal Regulations, 2010 CFR

2010-07-01

... duration of isolation. History of seizure disorder other than early febrile convulsions. Malignancies... or drug use. Conditions requiring continuous medication for control (e.g., antihistamines, steroids, barbiturates, moodaltering drugs, or insulin). Meniere's disease. Hemoglobinopathies. Obstructive or...

Corrigendum to ;Monoalkylated barbiturate derivatives: X-ray crystal structure, theoretical studies, and biological activities; [J. Mol. Struct. 1141 (2017) 624-633

NASA Astrophysics Data System (ADS)

Barakat, Assem; Al-Majid, Abdullah Mohammed; Soliman, Saied M.; Islam, Mohammad Shahidul; Ghawas, Hussain Mansur; Yousuf, Sammer; Choudhary, M. Iqbal; Wadood, Abdul

2017-09-01

;The correct CCDC reference for the compound 3k is 1546475 instead of 1024287 as mentioned in the text on page 625. The authors regret this error and would like to apologize for any inconvenience caused to anyone.;

21 CFR 522.775 - Doxapram.

Code of Federal Regulations, 2011 CFR

2011-04-01

... anesthesia, 0.5 mg/lb in inhalation anesthesia; for intravenous use in horses at 0.25 mg/lb body weight in barbiturate anesthesia, 0.2 mg/lb in inhalation anesthesia, 0.25 mg/lb with chloral hydrate with or without... horses to stimulate respiration during and after general anesthesia; or to speed awakening and return of...

Restrictions in Means for Suicide: An Effective Tool in Preventing Suicide: The Danish Experience

ERIC Educational Resources Information Center

Nordentoft, Merete; Qin, Ping; Helweg-Larsen, Karin

2007-01-01

Restriction of means for suicide is an important part of suicide preventive strategies in different countries. The effect on method-specific suicide rate and overall suicide rate of restrictions on availability of carbon monoxide, barbiturates, and dextropropoxyphene was examined. From 1970 to 2000, overall suicide mortality and method-specific…

Patterns of Psychiatric Need and Intervention among U. S. Army Troops of the Vietnam Conflict

DTIC Science & Technology

1982-10-01

symptomatic, command referred and forensic cases, plus attendant work) _______ ________ __________ b. Direct treatment of patients...barbiturate to facilitate recall, abreaction, and reintegration) C 1 2 3 4 5 U C 1 2 3 4 5 U C 1 2 3 4 5 U Hypnosis : (similar but without

Determination of sedative hypnotics in sewage sludge by pressurized liquid extraction with high-performance liquid chromatography and tandem mass spectrometry.

PubMed

Arbeláez, Paula; Granados, Judith; Borrull, Francesc; Marcé, Rosa Maria; Pocurull, Eva

2014-12-01

This paper describes a method for the determination of eight sedative hypnotics (benzodiazepines and barbiturates) in sewage sludge using pressurized liquid extraction and liquid chromatography with tandem mass spectrometry. Pressurized liquid extraction operating conditions were optimized and maximum recoveries were reached using methanol under the following operational conditions: 100ºC, 1500 psi, extraction time of 5 min, one extraction cycle, flush volume of 60% and purge time of 120 s. Pressurized liquid extraction recoveries were higher than 88% for all the compounds except for carbamazepine (55%). The repeatability and reproducibility between days, expressed as relative standard deviation (n = 5), were lower than 6 and 10%, respectively. The detection limits for all compounds were lower than 12.5 μg/kg of dry weight. The method was applied to determine benzodiazepines and barbiturates in sewage sludge from urban sewage treatment plants, and carbamazepine showed the highest concentration (7.9-18.9 μg/kg dry weight). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Impact of helical organization on the photovoltaic properties of oligothiophene supramolecular polymers† †Electronic supplementary information (ESI) available: Synthesis and characterization of 3 and 4, UV-vis spectra, solar cell device properties and AFM images. See DOI: 10.1039/c7sc05093c

PubMed Central

Ouchi, Hayato; Kizaki, Takahiro; Yamato, Masaki; Lin, Xu; Hoshi, Nagahiro; Silly, Fabien; Kajitani, Takashi; Fukushima, Takanori

2018-01-01

Helical self-assembly of functional π-conjugated molecules offers unique photochemical and electronic properties in the spectroscopic level, but there are only a few examples that demonstrate their positive impact on the optoelectronic device level. Here, we demonstrate that hydrogen-bonded tapelike supramolecular polymers of a barbiturated oligo(alkylthiophene) show notable improvement in their photovoltaic properties upon organizing into helical nanofibers. A tapelike hydrogen-bonded supramolecular array of barbiturated oligo(butylthiophene) molecules was directly visualized by STM at a liquid–solid interface. TEM, AFM and XRD revealed that the tapelike supramolecular polymers further organize into helical nanofibers in solution and bulk states. Bulk heterojunction solar cells of the helical nanofibers and soluble fullerene showed a power conversion efficiency of 4.5%, which is markedly high compared to that of the regioisomer of butyl chains organizing into 3D lamellar agglomerates. PMID:29780493

Remote Photoregulated Ring Gliding in a [2]Rotaxane via a Molecular Effector.

PubMed

Tron, Arnaud; Pianet, Isabelle; Martinez-Cuezva, Alberto; Tucker, James H R; Pisciottani, Luca; Alajarin, Mateo; Berna, Jose; McClenaghan, Nathan D

2017-01-06

A molecular barbiturate messenger, which is reversibly released/captured by a photoswitchable artificial molecular receptor, is shown to act as an effector to control ring gliding on a distant hydrogen-bonding [2]rotaxane. Thus, light-driven chemical communication governing the operation of a remote molecular machine is demonstrated using an information-rich neutral molecule.

21 CFR 522.775 - Doxapram.

Code of Federal Regulations, 2013 CFR

2013-04-01

... No. 000010 in § 510.600(c) of this chapter. (c) Conditions of use—(1) Amount. For intravenous use in dogs and cats at a dose of 21/2 to 5 mg per pound (/lb) body weight in barbiturate anesthesia, 0.5 mg... repeated in 15 to 20 minutes if necessary. (2) Indications for use. Administer to dogs, cats, and horses to...

21 CFR 522.775 - Doxapram.

Code of Federal Regulations, 2014 CFR

2014-04-01

... No. 000010 in § 510.600(c) of this chapter. (c) Conditions of use—(1) Amount. For intravenous use in dogs and cats at a dose of 21/2 to 5 mg per pound (/lb) body weight in barbiturate anesthesia, 0.5 mg... repeated in 15 to 20 minutes if necessary. (2) Indications for use. Administer to dogs, cats, and horses to...

21 CFR 522.1642 - Oxymorphone hydrochloride injection.

Code of Federal Regulations, 2012 CFR

2012-04-01

... chloride. (b) Sponsor. See No. 060951 in § 510.600(c) of this chapter. (c) Conditions of use. (1) The drug... intramuscular, subcutaneous or intravenous administration to cats and dogs as follows: Animal Body weight....0 Cats Small 0.4-0.75 Large 0.75-1.5 (2) Do not mix with a barbiturate in the same syringe to...

21 CFR 522.775 - Doxapram.

Code of Federal Regulations, 2012 CFR

2012-04-01

... Nos. 000010 and 015914 in § 510.600(c) of this chapter. (c) Conditions of use—(1) Amount. For intravenous use in dogs and cats at a dose of 21/2 to 5 mg per pound (/lb) body weight in barbiturate... be repeated in 15 to 20 minutes if necessary. (2) Indications for use. Administer to dogs, cats, and...

Amphetamines, Barbiturates and Hallucinogens; An Analysis of Use, Distribution, and Control. Final Report.

ERIC Educational Resources Information Center

McGlothlin, William H.

This report is the third of three monographs to provide perspectives on the use, distribution, and control of illicit drugs. The first, conducted in 1971, described the prevalence, use patterns, sources, distribution, and economics of the marihuana market. The second (1972) estimated the cost, benefits, and potential of approaches to narcotic…

Substance Use by Fourth-Year Students at 13 U.S. Medical Schools.

ERIC Educational Resources Information Center

Conard, Scott; And Others

1988-01-01

A study investigated drug use by fourth-year medical students in 13 schools and compared drug use patterns with those of an age- and sex-matched cohort. Medical students reported less use of marijuana, cocaine, cigarettes, LSD, barbiturates, and amphetamines, similar use of opiates, and slightly more use of tranquilizers and alcohol. (MSE)

Antiemetics With Concomitant Sedative Use in Civil Aviation Pilot Fatalities: From 2000 to 2006

DTIC Science & Technology

2007-10-01

Unclassified Unclassified 13 Form DOT F 1700.7 (8-72) Reproduction of completed page authorized iii CONTENTS INTRODUCTION...sedative hypnotics , and ethanol. Antiemetics and drugs with antiemetic properties such as metoclopramide, diphenhydramine (a sedating...antihistamines, ethanol, barbiturates, serotonin modulators, and/or sedative- hypnotics . Antihistamines such as diphenhydramine are commonly used. The

DIETARY EXPOSURE OF PHENOBARBITAL TO MALE AND FEMALE CD1 MICE FOR 2 OR 7 DAYS: EXAMINATION OF IN-LIFE, HEPATOCELLULAR ENZYME, PROLIFERATION, AND GENE EXPRESSION RESPONSES.

EPA Science Inventory

Phenobarbital (PB) is a barbiturate used to relieve anxiety and control epilepsy. PB is also an archetypical inducer of the constitutive androstane receptor (CAR), resulting in liver hypertrophy in humans and both liver hypertrophy and hyperplasia in rodents. In this study, male ...

A Review of Palliative Sedation.

PubMed

Bobb, Barton

2016-09-01

Palliative sedation has become a standard practice to treat refractory symptoms at end-of-life. Dyspnea and delirium are the two most commonly treated symptoms. The medications used in palliative sedation are usually benzodiazepines, barbiturates, antipsychotics, and/or anesthetics. Some ethical considerations remain, especially surrounding the use of palliative sedation in psychological distress and existential suffering. Copyright © 2016 Elsevier Inc. All rights reserved.

[Effects of acupuncture stimulation of different acupoint groups on sleeping latency, serum and hippocampal TNF-α and IL-25 contents in rats with gastric mucosal injury].

PubMed

Huang, Ying-Hua; Li, Qian; Yang, Ping; Yan, Ya-Nan; Ma, Hui-Fang

2015-04-01

To observe the effect of acupuncture intervention on gastric ulcer (GU) and sleeping quality from the viewpoint of brain-gut axis which plays an important role in the regulation of many vital functions in the body. Forty male Wistar rats were randomized into normal control, GU model, acupuncture of "Zhongwan"(CV 12)-"Zusanli"(ST 36, gastric function regulating acupoints), acupuncture of "Shenmai" (BL 62)-"Zhaohai" (KI 6, sleep-promotion acupoints), and acupuncture of CV 12-ST 36+ BL 62-KI 6 (combined treatment) groups, with 8 rats in each group. GU model was established by intragastric perfusion of dehydrated alcohol (1 mL/rat), and sleep model established by intraperitoneal injection of pentobarbital sodium (40 mg/kg) after the last treatment. The abovementioned acupoints were punctured with filiform needles and stimulated by manipulating the needle for about 30 s, once every 5 min during 20 min of needle retention. The treatment was conducted once daily for five days. The contents of tumor necrosis factor-alpha (TNF-α) and interleukin-25(IL-25) in the serum and hippocampal tissues were detected by ELISA. Compared with the normal control group, the gastric ulcer index score, barbiturate-induced sleeping time, and TNF-α and IL-25 contents in both serum and hippocampus were significantly increased in the model group (P < 0.01). Following acupuncture treatment, in comparison with the model group, the gastric ulcer index score, barbiturate-induced sleeping time, and TNF-α and IL-25 contents in both serum and hippocampus were significantly down-regulated in the CV 12-ST 36, BL 62-KI 6 and combined treatment groups (P < 0.01, P < 0.05). The effects of the CV 12-ST 36 and combined treatment groups were remarkably superior to those of the BL 62-KI 6 group in down-regulating ulcer index score, serum IL-25, and hippocampal TNF-α and IL-25 contents (P < 0.01, P < 0.05). In addition, the effects of the BL 62-KI 6 and combined treatment groups was considerably better than that of the CV 12-ST 36 group in shortening barbiturate-induced sleeping time (P < 0.01, P < 0.05). The effect of the combined treatment group was markedly better than that of the CV 12-ST 36 and BL 62-KI 6 groups in lowering serum TNF-α content (P < 0.05). Acupuncture stimulation of CV 12, ST 36, KI 6 and BL 62 can relieve the gastric mucosal lesion, and shorten barbiturate-induced sleeping time in gastric ulcer rats, which may be related to its effects in reducing TNF-α and IL-25 contents in the serum and hippocampus tissues, suggesting a correlation between the gastrointestinal disorder and sleeping.

A second dihydroorotate dehydrogenase (Type A) of the human pathogen Enterococcus faecalis: expression, purification, and steady-state kinetic mechanism.

PubMed

Marcinkeviciene, J; Jiang, W; Locke, G; Kopcho, L M; Rogers, M J; Copeland, R A

2000-05-01

We report the identification, expression, and characterization of a second Dihydroorotate dehydrogenase (DHODase A) from the human pathogen Enterococcus faecalis. The enzyme consists of a polypeptide chain of 322 amino acids that shares 68% identity with the cognate type A enzyme from the bacterium Lactococcus lactis. E. faecalis DHODase A catalyzed the oxidation of l-dihydroorotate while reducing a number of substrates, including fumarate, coenzyme Q(0), and menadione. The steady-state kinetic mechanism has been determined with menadione as an oxidizing substrate at pH 7.5. Initial velocity and product inhibition data suggest that the enzyme follows a two-site nonclassical ping-pong kinetic mechanism. The absorbance of the active site FMN cofactor is quenched in a concentration-dependent manner by titration with orotate and barbituric acid, two competitive inhibitors with respect to dihydroorotate. In contrast, titration of the enzyme with menadione had no effect on FMN absorbance, consistent with nonoverlapping binding sites for dihyroorotate and menadione, as suggested from the kinetic mechanism. The reductive half-reaction has been shown to be only partially rate limiting, and an attempt to evaluate the slow step in the overall reaction has been made by simulating orotate production under steady-state conditions. Our data indicate that the oxidative half-reaction is a rate-limiting segment, while orotate, most likely, retains significant affinity for the reduced enzyme, as suggested by the product inhibition pattern. Copyright 2000 Academic Press.

Thiopental inhibits nitric oxide production in rat aorta.

PubMed

Castillo, C; Asbun, J; Escalante, B; Villalón, C M; López, P; Castillo, E F

1999-12-01

We studied whether thiopental affects endothelial nitric oxide dependent vasodilator responses and nitrite production (an indicator of nitric oxide production) elicited by acetylcholine, histamine, and A23187 in rat aorta (artery in which nitric oxide is the main endothelial relaxant factor). In addition, we evaluated the barbiturate effect on nitric oxide synthase (NOS) activity in both rat aorta and kidney homogenates. Thiopental (10-100 microg/mL) reversibly inhibited the endothelium-dependent relaxation elicited by acetylcholine, histamine, and A23187. On the contrary, this anesthetic did not modify the endothelium-independent but cGMP-dependent relaxation elicited by sodium nitroprusside (1 nM - 1 microM) and nitroglycerin (1 nM - 1 microM), thus excluding an effect of thiopental on guanylate cyclase of vascular smooth muscle. Thiopental (100 microg/mL) inhibited both basal (87.8+/-14.3%) and acetylcholine- or A23187-stimulated (78.6+/-3.9 and 39.7+/-5.6%, respectively) production of nitrites in aortic rings. In addition the barbiturate inhibited (100 microg/mL) the NOS (45+/-4 and 42.8+/-9%) in aortic and kidney homogenates, respectively (measured as 14C-labeled citrulline production). In conclusion, thiopental inhibition of endothelium-dependent relaxation and nitrite production in aortic rings strongly suggests an inhibitory effect on NOS. Thiopental inhibition of the NOS provides further support to this contention.

What predicts the change from episodic to chronic migraine?

PubMed

Bigal, Marcelo E; Lipton, Richard B

2009-06-01

Because migraine worsens in a sizeable subgroup of sufferers, but not in most, identifying factors that predict the change from episodic into chronic migraine is of extreme interest and should be seen as a priority in headache research. Potentially remediable risk factors include frequency of migraine attacks, obesity, excessive use of medications containing opioids and barbiturates, caffeine overuse, stressful life events, depression, sleep disorders and cutaneous allodynia. While we wait for evidence regarding the benefits of risk factor modifications in the prevention of chronic migraine, several interventions are justifiable based on their other established benefits. For example, decreasing headache frequency with behavioral and pharmacological interventions will decrease current disability even if it does not modify clinical course. Monitoring the body mass index and encouraging maintenance of normal body weight is good practice in patients with and without migraine. Avoiding overuse of caffeine is desirable apart from its potential benefit in preventing progression. Sleep problems should be investigated and treated. Psychiatric comorbidities should be identified and addressed. Medications containing opioids and barbiturates should be reserved for a few selected cases of migraine, and their use should be monitored. For these interventions, the possibility of preventing progression may motivate clinicians to offer good care and patients to engage in the treatment plan.

Spectroscopic and Computational Investigations of Ligand Binding to IspH: Discovery of Non-diphosphate Inhibitors

DOE Office of Scientific and Technical Information (OSTI.GOV)

O'Dowd, Bing; Williams, Sarah; Wang, Hongxin

Isoprenoid biosynthesis is an important area for anti-infective drug development. One isoprenoid target described is (E)-1-hydroxy-2-methyl-but-2-enyl 4-diphosphate (HMBPP) reductase (IspH), which forms isopentenyl diphosphate and dimethylallyl diphosphate from HMBPP in a 2H + /2e - reduction. IspH contains a 4 Fe-4 S cluster, and in this work, we first investigated how small molecules bound to the cluster by using HYSCORE and NRVS spectroscopies. The results of these, as well as other structural and spectroscopic investigations, led to the conclusion that, in most cases, ligands bound to IspH 4 Fe-4 S clusters by η 1 coordination, forming tetrahedral geometries at themore » unique fourth Fe, ligand side chains preventing further ligand (e.g., H 2 O, O 2 ) binding. Based on these ideas, we used in silico methods to find drug-like inhibitors that might occupy the HMBPP substrate binding pocket and bind to Fe, leading to the discovery of a barbituric acid analogue with a K i value of ≈500 nm against Pseudomonas aeruginosa IspH.« less

2-Methylpyridinium/pyridinium 5-(2,4-dinitrophenyl)-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-olates as potent anticonvulsant agents—synthesis and crystal structure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mangaiyarkarasi, G.; Kalaivani, D., E-mail: kalaivbalaj@yahoo.co.in

2013-12-15

The molecular salt, 2-methylpyridinium 5-(2,4-dinitrophenyl)-2,6-dioxo-1,2,3,6-tetrahydropy-rimidin-4-olate) (I), is prepared from the ethanolic solution of 1-chloro-2,4-dinitrobenzene, pyrimidine-2,4,6-(1H,3H,5H)-trione (barbituric acid) and 2-methylpyridine at room temperature, and the molecular salt, pyridinium 5-(2,4-dinitrophenyl)-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-olate (II), is prepared from the same reactants, by dissolving them in hot DMSO and ethanol mixture at 70°C. The structures of I and II are characterized by visible, IR, {sup 1}H-NMR, {sup 13}C-NMR and elemental analysis and confirmed by single crystal X-ray analysis. Both the salts crystallize in triclinic crystal system with sp. gr. P-bar1. They possess noticeable anticonvulsant activity even at low concentration (25 mg/kg). Acute toxicity studies of these complexesmore » indicate that LD{sub 50} values are greater than 1500 mg/kg and the tested animals do not show any behavioural changes.« less

Chemical models and their mechanistic implications for the transformation of 6-cyanouridine 5'-monophosphate catalyzed by orotidine 5'-monophosphate decarboxylase.

PubMed

Chien, Tun-Cheng; Jen, Cheng-Hung; Wu, Yuen-Jen; Liao, Chen-Chieh

2008-01-01

Orotidine 5'-monophosphate decarboxylase (ODCase) catalyzes an unprecedented transformation of 6- cyanouridine 5'-monophosphate (6-CN-UMP) into barbiturate nucleoside 5'-monophosphate (6-hydroxyuridine 5'-monophosphate, BMP). The reactions of 6- cyano-1,3-dimethyluracil toward various nucleophilic conditions have been studied as chemical models in order to understand the possible mechanism for the ODCase-catalyzed transformation of 6-CN-UMP.

Department of Clinical Investigation Annual Research Progress Report, Fiscal Year 1989

DTIC Science & Technology

1989-09-30

and DES. Patients with a history of deep vein thrombosis, cerebral embolus, stroke , congestive heart failure, or ischemic heart disease will not be...Adolescent Health Care 9(6): 498-500, 1988 Weir MR Intravascular Injuries from Intramuscular Penicillin. Clinical Pediatrics 27(2): 85-90, 1988 Weir...Military Medicine 154(9): 455-57, 1989 Piatt JH, Goodkin R Barbiturates in Severe Head Injury . J Neurosurgery 70(3): 501-02, 1989 * Piatt JH

Highlights from the Worldwide Survey of Nonmedical Drug Use and Alcohol Use Among Military Personnel: 1980.

DTIC Science & Technology

1980-11-14

Prepared with assistance of: Yukiko Gamnes and Edward Farley W9 KEY WORDS (Continue on revere.r side it necessary and identify by block number) Drug use... side if neresestry aund idennty by block ntimber) his survey report provides a comprehensive, detailed and accurate estimallte or the preval ence of drug...34 Other Uppers ............. Preludin, Ritalin , Sandrex Tranquilizers ............ Valium, Librium, Miltown Barbiturates ............. Seconal (reds

Antagonism Between Luminal and Caffeine, Studied by the Use of Radioisotopes; RECHERCHES SUR LES BARBITURIQUES RADIOACTIFS: LA DISTRIBUTION DU LUMINAL DANS L'ORGANISME ANIMAL EN PRESENCE DE CAFEINE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aliprandi, B.; Masironi, R.

1959-10-31

The normal pattern of distribution of luminal in the animal organism was determined in mice using a tracer technique. The effect of an antagonistic drug, e.g., caffeine, on this normal distribution pattern was studied. The results confirmed the hypothesis of the in vivo breaking of the barbituric ring. (J.S.R.)

21 CFR 522.1642 - Oxymorphone hydrochloride injection.

Code of Federal Regulations, 2011 CFR

2011-04-01

... (pounds) Dosage (milligram) Dogs 2 to 5 0.75 5 to 15 0.75-1.5 15 to 30 1.5-2.5 30 to 60 2.5-4.0 Over 60 4.0 Cats Small 0.4-0.75 Large 0.75-1.5 (2) Do not mix with a barbiturate in the same syringe to... Section 522.1642 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

21 CFR 522.1642 - Oxymorphone hydrochloride injection.

Code of Federal Regulations, 2010 CFR

2010-04-01

... (pounds) Dosage (milligram) Dogs 2 to 5 0.75 5 to 15 0.75-1.5 15 to 30 1.5-2.5 30 to 60 2.5-4.0 Over 60 4.0 Cats Small 0.4-0.75 Large 0.75-1.5 (2) Do not mix with a barbiturate in the same syringe to... Section 522.1642 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

Thiopentone anaesthesia at Pearl Harbor.

PubMed

Bennetts, F E

1995-09-01

A wartime embargo on casualty figures and an imprecise contemporary editorial contributed to the persisting belief that a grossly excessive mortality rate from barbiturate anaesthesia for surgery of the injured occurred after the Japanese attack on the American bases in Hawaii in December 1941. From accounts by surgical staff and official hospital records which have become available through US Freedom of Information legislation, it is clear that the rumoured death rate from this cause has been greatly exaggerated.

THE INACTIVATION OF DILUTE SOLUTIONS OF CRYSTALLINE TRYPSIN BY X-RADIATION

PubMed Central

McDonald, Margaret R.

1955-01-01

The proteolytic activity of dilute solutions of clystalline trypsin is destroyed by x-rays, the amount of inactivation being an exponential function of the radiation dose. The reaction yield increases steadily with increasing concentration of trypsin, varying, as the concentration of enzyme is increased from 1 to 300 µM, from 0.068 to 0.958 micromole of trypsin per liter inactivated per 1000 r with 0.005 N hydrochloric acid as the solvent, from 0.273 to 0.866 with 0.005 N sulfuric acid as the solvent, and from 0.343 to 0.844 with 0.005 N nitric acid as the solvent. When the reaction yields are plotted as a function of the initial concentration of trypsin, they fall on a curve given by the expression Y α XK, in which Y is the reaction yield, X is the concentration of trypsin, and K is a constant equal to 0.46, 0.20, and 0.16, respectively, with 0.005 N hydrochloric, sulfuric, and nitric acids as solvents. The differences between the reaction yields found with chloride and sulfate ions in I to 10 µM trypsin solutions are significant only in the pH range from 2 to 4. The amount of inactivation obtained with a given dose of x-rays depends on the pH of the solution being irradiated and the nature of the solvent. The reaction yield-pH curve is a symmetrical one, with minimum yields at about pH 7. Buffers such as acetate, citrate, borate and barbiturate, and other organic molecules such as ethanol and glucose, in concentrations as low as 20 µM, inhibit the inactivation of trypsin by x-radiation. Sigmoid inactivation-dose curves instead of exponential ones are obtained in the presence of ethanol. The reaction yields for the inactivation of trypsin solutions by x-rays are approximately 1.5 times greater when the irradiation is done at 26°C. than when it is done at 5°C., when 0.005 N hydrochloric acid is the solvent. The dependence on temperature is less when 0.005 N sulfuric acid is used, and is negligible with 0.005 N nitric acid. The difficulties involved in interpreting radiation effects in aqueous systems, and in comparing the results obtained under different experimental conditions, are discussed. PMID:14367774

Chemical models and their mechanistic implications for the transformation of 6-cyanouridine 5'-monophosphate catalyzed by orotidine 5'-monophosphate decarboxylase.

PubMed

Wu, Yuen-Jen; Liao, Chen-Chieh; Jen, Cheng-Hung; Shih, Yu-Chiao; Chien, Tun-Cheng

2010-07-14

The reactions of 6-cyano-1,3-dimethyluracil have been studied as chemical models to illustrate the mechanism for the transformation of 6-cyanouridine 5'-monophosphate (6-CN-UMP) to barbiturate ribonucleoside 5'-monophosphate (BMP) catalyzed by orotidine 5'-monophosphate decarboxylase (ODCase). The results suggest that the Asp residue in the ODCase active site plays the role of a general base in the transformation.

Evaluation of plasma levels of melatonin after midazolam or sodium thiopental anesthesia in children.

PubMed

Muñoz-Hoyos, Antonio; Heredia, Francisco; Moreno, Francisco; García, Joaquín José; Molina-Carballo, Antonio; Escames, Germaine; Acuña-Castroviejo, Darío

2002-05-01

Midazolam and sodium thiopental are two commonly used drugs in anesthesia for minor surgical procedures in children. A relationship exists between benzodiazepines (BNZ), barbiturates and melatonin. Whereas these drugs increase pineal melatonin production, the indoleamine amplifies the effects of both BNZ and barbiturates on the central nervous system (CNS). Our purpose was thus to analyze the plasma levels of melatonin before and during midazolam or sodium thiopental anesthesia in children subjected to ambulatory surgical procedures. Midazolam (0.4 mg/kg) or sodium thiopental (5 mg/kg) were administered i.v. to 33 and 32 children (aged between 2 and 14 yr), respectively, and blood samples were taken before and 5, 10 and 20 min after the drugs were administered. Melatonin was measured in plasma by a commercial radioimmunoassay kit previously standardized in our laboratory. The results showed that neither midazolam nor sodium thiopental anesthesia significantly affected the levels of melatonin studied at anytime. Significant correlations were found comparing the levels of melatonin between the different times studied. These results suggest that midazolam or sodium thiopental did not affect melatonin production by the pineal gland, thus avoiding a possible potentiating effect of the indoleamine on the central effects of these drugs during anesthesia. However, the possibility that changes in melatonin had been masked by the antioxidant role of the neurohormone are discussed.

Association between anticonvulsant drugs and teeth-grinding in children and adolescents with cerebral palsy.

PubMed

Ortega, A O L; Dos Santos, M T B R; Mendes, F M; Ciamponi, A L

2014-09-01

The relation between teeth-grinding and the use of drugs acting on the central nervous system of cerebral palsy (CP) patients has not yet been described. The aim of this research was to evaluate the presence or absence of teeth-grinding (sleep and/or awake periods) in normal and in CP children and adolescents, as well as the association of teeth-grinding and use of anticonvulsant drugs. The sample consisted of 207 children and adolescents, divided into three groups: G1, individuals with CP who did not take anticonvulsant drugs; G2, individuals with CP administered medications on a regular basis; and CG, normal individuals. Logistic regression analyses were performed to evaluate the association of teeth-grinding with some variables. No significant statistical differences were observed regarding the presence or absence of teeth-grinding when G1 and G2 were compared. However, compared with the CG, a statistically significant difference was determined, with the CG showing fewer children presenting teeth-grinding (P < 0·001). Among those children/adolescents prescribed drug therapy, the barbiturate group showed a greater frequency of teeth-grinding. CP children and adolescents show a greater and significant presence of grinding of the teeth compared with normal individuals. Subjects taking barbiturate drugs showed greater presence of teeth-grinding, than those who were taking medications from the other groups of anticonvulsant drugs. © 2014 John Wiley & Sons Ltd.

Acute migraine medication adherence, migraine disability and patient satisfaction: A naturalistic daily diary study.

PubMed

Seng, Elizabeth K; Robbins, Matthew S; Nicholson, Robert A

2017-09-01

Objective To examine the influence of acute migraine medication adherence on migraine disability and acute medication satisfaction. Methods Adults with migraine completed three months of daily electronic diaries assessing headache symptoms, acute medication taken, acute medication satisfaction, and daily migraine disability. Repeated measures mixed-effects models examined the effect of initial medication type [migraine-specific medication (MSM) vs. over-the-counter analgesic (OTC) vs. an opiate/barbiturate], the severity of pain at dosing, and their interaction with daily migraine disability and satisfaction with acute medication. Results Participants (N = 337; 92.5% female; 91.1% Caucasian, non-Hispanic; 84.0% with episodic migraine) recorded 29,722 diary days. Participants took acute medication on 96.5% of 8090 migraine days. MSM was most frequently taken first (58%), followed by OTC (29.9%) and an opiate/barbiturate (12.1%). Acute medication was most frequently taken when pain was mild (41.2%), followed by moderate (37.7%) and severe pain (11.4%). Initially dosing with MSM while pain was mild was associated with the lowest daily disability [medication × pain at dosing F (4, 6336.12) = 58.73, p < .001] and highest acute medication satisfaction [medication × pain at dosing F (4, 3867.36) = 24.00, p < .001]. Conclusion Using an MSM (triptan or ergot) first was associated with the lowest migraine disability and highest acute medication satisfaction.

Anxiolytic-like effect of Carvacrol (5-isopropyl-2-methylphenol) in mice: involvement with GABAergic transmission.

PubMed

Melo, Francisca Helvira Cavalcante; Venâncio, Edith Teles; de Sousa, Damião Pergentino; de França Fonteles, Marta Maria; de Vasconcelos, Silvânia Maria Mendes; Viana, Glauce Socorro Barros; de Sousa, Francisca Cléa Florenço

2010-08-01

Carvacrol (5-isopropyl-2-methylphenol) is a monoterpenic phenol present in the essencial oil of many plants. It is the major component of the essential oil fraction of oregano and thyme. This work presents the behavioral effects of carvacrol in animal models of elevated plus maze (EPM), open field, Rotarod and barbiturate-induced sleeping time tests in mice. Carvacrol (CVC) was administered orally, in male mice, at single doses of 12.5; 25 and 50 mg/kg while diazepam 1 or 2 mg/kg was used as standard drug and flumazenil (2.5 mg/kg) was used to elucidate the possible anxiolytic mechanism of CVC on the plus maze test. The results showed that CVC, at three doses, had no effect on the spontaneous motor activity in the Rotarod test nor in the number of squares crossed in the open-field test. However, CVC decreased the number of groomings in the open-field test. In the plus maze test, CVC, at three doses significantly increased all the observed parameters in the EPM test and flumazenil was able to reverse the effects of diazepam and CVC. Therefore, CVC did not alter the sleep latency and sleeping time in the barbiturate-induced sleeping time test. These results show that CVC presents anxiolytic effects in the plus maze test which are not influenced by the locomotor activity in the open-field test.

A Small-Molecule Inhibitor of Human DNA Polymerase η Potentiates the Effects of Cisplatin in Tumor Cells.

PubMed

Zafar, Maroof K; Maddukuri, Leena; Ketkar, Amit; Penthala, Narsimha R; Reed, Megan R; Eddy, Sarah; Crooks, Peter A; Eoff, Robert L

2018-02-20

Translesion DNA synthesis (TLS) performed by human DNA polymerase eta (hpol η) allows tolerance of damage from cis-diamminedichloroplatinum(II) (CDDP or cisplatin). We have developed hpol η inhibitors derived from N-aryl-substituted indole barbituric acid (IBA), indole thiobarbituric acid (ITBA), and indole quinuclidine scaffolds and identified 5-((5-chloro-1-(naphthalen-2-ylmethyl)-1H-indol-3-yl)methylene)-2-thioxodihydropyrimidine-4,6(1H,5H)-dione (PNR-7-02), an ITBA derivative that inhibited hpol η activity with an IC 50 value of 8 μM and exhibited 5-10-fold specificity for hpol η over replicative pols. We conclude from kinetic analyses, chemical footprinting assays, and molecular docking that PNR-7-02 binds to a site on the little finger domain and interferes with the proper orientation of template DNA to inhibit hpol η. A synergistic increase in CDDP toxicity was observed in hpol η-proficient cells co-treated with PNR-7-02 (combination index values = 0.4-0.6). Increased γH2AX formation accompanied treatment of hpol η-proficient cells with CDDP and PNR-7-02. Importantly, PNR-7-02 did not impact the effect of CDDP on cell viability or γH2AX in hpol η-deficient cells. In summary, we observed hpol η-dependent effects on DNA damage/replication stress and sensitivity to CDDP in cells treated with PNR-7-02. The ability to employ a small-molecule inhibitor of hpol η to improve the cytotoxic effect of CDDP may aid in the development of more effective chemotherapeutic strategies.

Early drug discovery and the rise of pharmaceutical chemistry.

PubMed

Jones, Alan Wayne

2011-06-01

Studies in the field of forensic pharmacology and toxicology would not be complete without some knowledge of the history of drug discovery, the various personalities involved, and the events leading to the development and introduction of new therapeutic agents. The first medicinal drugs came from natural sources and existed in the form of herbs, plants, roots, vines and fungi. Until the mid-nineteenth century nature's pharmaceuticals were all that were available to relieve man's pain and suffering. The first synthetic drug, chloral hydrate, was discovered in 1869 and introduced as a sedative-hypnotic; it is still available today in some countries. The first pharmaceutical companies were spin-offs from the textiles and synthetic dye industry and owe much to the rich source of organic chemicals derived from the distillation of coal (coal-tar). The first analgesics and antipyretics, exemplified by phenacetin and acetanilide, were simple chemical derivatives of aniline and p-nitrophenol, both of which were byproducts from coal-tar. An extract from the bark of the white willow tree had been used for centuries to treat various fevers and inflammation. The active principle in white willow, salicin or salicylic acid, had a bitter taste and irritated the gastric mucosa, but a simple chemical modification was much more palatable. This was acetylsalicylic acid, better known as Aspirin®, the first blockbuster drug. At the start of the twentieth century, the first of the barbiturate family of drugs entered the pharmacopoeia and the rest, as they say, is history. Copyright © 2011 John Wiley & Sons, Ltd.

Piracetam and other structurally related nootropics.

PubMed

Gouliaev, A H; Senning, A

1994-05-01

Nearly three decades have now passed since the discovery of the piracetam-like nootropics, compounds which exhibit cognition-enhancing properties, but for which no commonly accepted mechanism of action has been established. This review covers clinical, pharmacokinetic, biochemical and behavioural results presented in the literature from 1965 through 1992 (407 references) of piracetam, oxiracetam, pramiracetam, etiracetam, nefiracetam, aniracetam and rolziracetam and their structural analogues. The piracetam-like nootropics are capable of achieving reversal of amnesia induced by, e.g., scopolamine, electroconvulsive shock and hypoxia. Protection against barbiturate intoxication is observed and some benefit in clinical studies with patients suffering from mild to moderate degrees of dementia has been demonstrated. No affinity for the alpha 1-, alpha 2-, beta-, muscarinic, 5-hydroxytryptamine-, dopamine, adenosine-A1-, mu-opiate, gamma-aminobutyric acid (GABA) (except for nefiracetam (GABAA)), benzodiazepine and glutamate receptors has been found. The racetams possess a very low toxicity and lack serious side effects. Increased turnover of different neurotransmitters has been observed as well as other biochemical findings, e.g., inhibition of enzymes such as prolylendopeptidase. So far, no generally accepted mechanism of action has, however, emerged. We believe that the effect of the racetams is due to a potentiation of already present neurotransmission and that much evidence points in the direction of a modulated ion flux by, e.g., potentiated calcium influx through non-L-type voltage-dependent calcium channels, potentiated sodium influx through alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor gated channels or voltage-dependent channels or decreases in potassium efflux. Effects on carrier mediated ion transport are also possible.

JPRS Report, Latin America, Reference Aid, Glossary of Spanish and Portuguese Narcotics Terms.

DTIC Science & Technology

1989-05-04

devils, seconal, barbiturates, amphetamines, LSD a "deal"—to make a connection to obtain drugs (Ar) to deal bread, dough , money "dirty money...drug addict federal police; feds, "G" men PCP; angel dust; phencyclidine bread, dough , money weapon (Ar) a fix, a jab to inject, to shoot up...used to cut heroin); manida, mannite, milk sugar brick (usually a kilogram of hashish or marijuana) bread, dough , money money laundering to

Virtual Reality Pain Control During Burn Wound Debridement of Combat-Related Burn Injuries Using Robot-Like Arm Mounted VR Goggles

DTIC Science & Technology

2011-07-01

naturally contracts as it heals. Physical therapy stretches help to counteract contraction, increasing skin elasticity, and en- hancing range of motion.3...excru- ciating pain during medical procedures such as wound clean- ing and physical therapy .4 Although opioids are the cornerstone analgesic for patients...Used at low doses, ketamine is a non-barbiturate intravenous anesthetic that is used as part of a multi-modal therapy . Ketamine does not cause

Synthesis and properties of 2-(4-substituted)butyl derivatives of some 2,3-dihydro-1,3-dioxo-1H-pyrrolo[3,4-c]pyridines.

PubMed

Sladowska, H; Szkatuła, D; Filipek, B; Maciag, D; Sapa, J; Zygmunt, M

2001-02-01

The synthesis of 2-(4-substituted)butyl derivatives of 4-alkoxy-2,3-dihydro-6-methyl-1,3-dioxo-1H-pyrrolo[3,4-c]pyridine (10-15) and the results of preliminary pharmacological screening are described in this paper. All the compounds tested showed a strong analgesic action, suppressed spontaneous locomotor activity and prolonged barbiturate sleep. Except 10, all significantly decreased systolic and diastolic blood pressure.

Non-health care facility anticonvulsant medication errors in the United States.

PubMed

DeDonato, Emily A; Spiller, Henry A; Casavant, Marcel J; Chounthirath, Thitphalak; Hodges, Nichole L; Smith, Gary A

2018-06-01

This study provides an epidemiological description of non-health care facility medication errors involving anticonvulsant drugs. A retrospective analysis of National Poison Data System data was conducted on non-health care facility medication errors involving anticonvulsant drugs reported to US Poison Control Centers from 2000 through 2012. During the study period, 108,446 non-health care facility medication errors involving anticonvulsant pharmaceuticals were reported to US Poison Control Centers, averaging 8342 exposures annually. The annual frequency and rate of errors increased significantly over the study period, by 96.6 and 76.7%, respectively. The rate of exposures resulting in health care facility use increased by 83.3% and the rate of exposures resulting in serious medical outcomes increased by 62.3%. In 2012, newer anticonvulsants, including felbamate, gabapentin, lamotrigine, levetiracetam, other anticonvulsants (excluding barbiturates), other types of gamma aminobutyric acid, oxcarbazepine, topiramate, and zonisamide, accounted for 67.1% of all exposures. The rate of non-health care facility anticonvulsant medication errors reported to Poison Control Centers increased during 2000-2012, resulting in more frequent health care facility use and serious medical outcomes. Newer anticonvulsants, although often considered safer and more easily tolerated, were responsible for much of this trend and should still be administered with caution.

Design of inhibitors of orotidine monophosphate decarboxylase using bioisosteric replacement and determination of inhibition kinetics.

PubMed

Poduch, Ewa; Bello, Angelica M; Tang, Sishi; Fujihashi, Masahiro; Pai, Emil F; Kotra, Lakshmi P

2006-08-10

Inhibitors of orotidine monophosphate decarboxylase (ODCase) have applications in RNA viral, parasitic, and other infectious diseases. ODCase catalyzes the decarboxylation of orotidine monophosphate (OMP), producing uridine monophosphate (UMP). Novel inhibitors 6-amino-UMP and 6-cyano-UMP were designed on the basis of the substructure volumes in the substrate OMP and in an inhibitor of ODCase, barbituric acid monophosphate, BMP. A new enzyme assay method using isothermal titration calorimetry (ITC) was developed to investigate the inhibition kinetics of ODCase. The reaction rates were measured by monitoring the heat generated during the decarboxylation reaction of orotidine monophosphate. Kinetic parameters (k(cat) = 21 s(-1) and KM = 5 microM) and the molar enthalpy (DeltaH(app) = 5 kcal/mol) were determined for the decarboxylation of the substrate by ODCase. Competitive inhibition of the enzyme was observed and the inhibition constants (Ki) were determined to be 12.4 microM and 29 microM for 6-aza-UMP and 6-cyano-UMP, respectively. 6-Amino-UMP was found to be among the potent inhibitors of ODCase, having an inhibition constant of 840 nM. We reveal here the first inhibitors of ODCase designed by the principles of bioisosterism and a novel method of using isothermal calorimetry for enzyme inhibition studies.

Influencing of resorption and side-effects of salicylic acid by complexing with beta-cyclodextrin.

PubMed

Szejtli, J; Gerlóczy, A; Sebestyén, G; Fónagy, A

1981-04-01

After oral administration of 14C-labelled salicylic acid and its beta-cyclodextrin complex to rats, the blood radioactivity-level increases in the first 2 h than decreases. The blood level obtained with the inclusion complex is somewhat but not significantly lower than with free acid. Since the resorption of cyclodextrin is a considerably slower process, it is very likely that the resorption of salicylic acid take place in the form of free acid after dissociation of the complex. The urinary excretion cumulative curves show that the free salicylic acid is completely excreted, while about 10% of the salicylic acid administered in the form of complex is lost. The cyclodextrin complex formation increases the pK value of all hydroxy-benzoic acids. Direct observations reveals that complex formation decreases the stomach-irritating effect of salicylic acid. The ratio of radioactivity was nearly the same in the organs of animals treated by both free salicylic and cyclodextrin complex.

Clinical characteristics of patients who overdose on multiple psychotropic drugs in Tokyo.

PubMed

Hori, Satoshi; Kinoshita, Kosaku

2016-01-01

The purpose of this study was to identify the clinical aspects leading to overdose of multiple psychotropic drugs, in order to determine areas which need attention in the proper treatment of overdose patients. Patients who were treated for overdose of psychotropic drugs at our emergency and critical center over two years were targeted. The clinical data was gathered from the medical records and database of all patients, including age, gender, vital signs, and laboratory data, drugs, and medical complications during hospital stay. In addition primary patient care at the emergency department was examined. Among the 277 patients treated during this study period, 255 (74.0%) used two or more types of psychotropic drugs. Risk factors associated with endotracheal intubation and aspiration pneumonitis included the use of antipsychotics and/or barbiturates as types of overdose drugs. The mean number of days in the ICU was 3.4 days. Seventy-four patients (26.7%) stayed 4 days or more in the ICU of which 16 patients (5.8%) still had suicidal thoughts. A significantly higher incidence of extended ICU stay or endotracheal intubation and aspiration pneumonitis was observed in the group who overdosed on more than 50 or 60 tablets of psychotropic drugs, respectively. Patients who ingested an overdose of more than 60 tablets of psychotropic drugs should be considered a high-risk group requiring intensive care with extended ICU stay. In case of including antipsychotics and/or barbiturates, the patient should be observed carefully due to a higher risk of medical complications.

Assisted suicide by oxygen deprivation with helium at a Swiss right-to-die organisation.

PubMed

Ogden, Russel D; Hamilton, William K; Whitcher, Charles

2010-03-01

In Switzerland, right-to-die organisations assist their members with suicide by lethal drugs, usually barbiturates. One organisation, Dignitas, has experimented with oxygen deprivation as an alternative to sodium pentobarbital. To analyse the process of assisted suicide by oxygen deprivation with helium and a common face mask and reservoir bag. This study examined four cases of assisted suicide by oxygen deprivation using helium delivered via a face mask. Videos of the deaths were provided by the Zurich police. Dignitas provided protocol and consent information. One man and three women were assisted to death by oxygen deprivation. There was wide variation in the time to unconsciousness and the time to death, probably due to the poor mask fit. Swiss law prevented attendants from effectively managing the face mask apparatus. Purposeless movements of the extremities were disconcerting for Dignitas attendants, who are accustomed to assisting suicide with barbiturates. None of the dying individuals attempted self-rescue. The dying process of oxygen deprivation with helium is potentially quick and appears painless. It also bypasses the prescribing role of physicians, effectively demedicalising assisted suicide. Oxygen deprivation with a face mask is not acceptable because leaks are difficult to control and it may not eliminate rebreathing. These factors will extend time to unconsciousness and time to death. A hood method could reduce the problem of mask fit. With a hood, a flow rate of helium sufficient to provide continuous washout of expired gases would remedy problems observed with the mask.

Increased release of norepinephrine and dopamine from canine kidney during bilateral carotid occlusion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bradley, T.; Hjemdahl, P.; DiBona, G.F.

1987-02-01

The renal overflow of norepinephrine (NE) and dopamine (DA) to plasma from the innervated kidney was studied at rest and during sympathetic nervous system activation by bilateral carotid artery occlusion (BCO) in vagotomized dogs under barbiturate or barbiturate/nitrous oxide anesthesia. BCO elevated arterial pressure and the arterial plasma concentration of NE, DA, and epinephrine (Epi). Renal vascular resistance (renal arterial pressure kept constant) increased by 15 +/- 7% and the net renal venous outflows (renal veno-arterial concentration difference x renal plasma flow) of NE and DA were enhanced. To obtain more correct estimates of the renal contribution to the renalmore » venous catecholamine outflow, they corrected for the renal extraction of arterial catecholamines, assessed as the extractions of (/sup 3/H)NE, (/sup 3/H)DA, or endogenous Epi. The (/sup 3/H)NE corrected renal NE overflow to plasma increased from 144 +/- 40 to 243 +/- 64 pmol-min/sup -1/ during BCO, which, when compared with a previous study of the (/sup 3/H)NE corrected renal NE overflow to plasma evoked by electrical renal nerve stimulation, corresponds to a 40% increase in nerve impulse frequency from approx. 0.6 Hz. If the renal catecholamine extraction was not taken into account the effect of BCO was underestimated. The renal DA overflow to plasma was about one-fifth of the NE overflow both at rest and during BCO, indicating that there was no preferential activation of noradrenergic or putative dopaminergic nerves by BCO.« less

Membrane extraction with thermodynamically unstable diphosphonic acid derivatives

DOEpatents

Horwitz, Earl Philip; Gatrone, Ralph Carl; Nash, Kenneth LaVerne

1997-01-01

Thermodynamically-unstable complexing agents which are diphosphonic acids and diphosphonic acid derivatives (or sulphur containing analogs), like carboxyhydroxymethanediphosphonic acid and vinylidene-1,1-diphosphonic acid, are capable of complexing with metal ions, and especially metal ions in the II, III, IV, V and VI oxidation states, to form stable, water-soluble metal ion complexes in moderately alkaline to highly-acidic media. However, the complexing agents can be decomposed, under mild conditions, into non-organic compounds which, for many purposes are environmentally-nondamaging compounds thereby degrading the complex and releasing the metal ion for disposal or recovery. Uses for such complexing agents as well as methods for their manufacture are also described.

21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Nicotinamide-ascorbic acid complex. 172.315... HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.315 Nicotinamide-ascorbic acid complex. Nicotinamide-ascorbic acid complex may be safely used in accordance with the following prescribed conditions...

Circadian manifestations of barbiturate habituation, addiction and withdrawal in the rat

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ehret, C. F.; Peraino, C.; Meinert, J. C.

1979-01-01

The present study uses circadian rhythm observations on rats to include diverse habituation and drug ingestion (phenobarbital) circumstances, including a comparison of the effect of pre-entrainment cycles of programmed feeding and illumination and subsequent conditions of exposure of duration sufficient to permit a steady-state in the appearance of circadian patterns derived from core-temperature telemetry and from automated food-consumption measurements. Finally, measurements were permitted to continue long enough after the drug was withdrawn from the diet to allow characterization of an abstinence syndrome, indicative of addiction.

Management of Intracranial Hypertension

PubMed Central

Rangel-Castillo, Leonardo; Gopinath, Shankar; Robertson, Claudia S.

2008-01-01

Effective management of intracranial hypertension involves meticulous avoidance of factors that precipitate or aggravate increased intracranial pressure. When intracranial pressure becomes elevated, it is important to rule out new mass lesions that should be surgically evacuated. Medical management of increased intracranial pressure should include sedation, drainage of cerebrospinal fluid, and osmotherapy with either mannitol or hypertonic saline. For intracranial hypertension refractory to initial medical management, barbiturate coma, hypothermia, or decompressive craniectomy should be considered. Steroids are not indicated and may be harmful in the treatment of intracranial hypertension resulting from traumatic brain injury. PMID:18514825

Pediatric intensive care treatment of uncontrolled status epilepticus.

PubMed

Wilkes, Ryan; Tasker, Robert C

2013-04-01

The critically ill mechanically ventilated child with ongoing seizures that are refractory to any treatment presents a distinct challenge in pediatric neurocritical care. The evidence base from randomized controlled trials on which anti-epileptic drug (AED) strategy should be used is inadequate. This review of refractory and super-refractory status epilepticus summarizes recent pediatric case series regarding definitions, the second-tier AED therapies once initial anticonvulsants have failed, and the experience of high-dose midazolam, barbiturate anesthesia, and volatile anesthetics for uncontrolled status epilepticus. Copyright © 2013 Elsevier Inc. All rights reserved.

Membrane extraction with thermodynamically unstable diphosphonic acid derivatives

DOEpatents

Horwitz, E.P.; Gatrone, R.C.; Nash, K.L.

1997-10-14

Thermodynamically-unstable complexing agents which are diphosphonic acids and diphosphonic acid derivatives (or sulphur containing analogs), like carboxyhydroxymethanediphosphonic acid and vinylidene-1,1-diphosphonic acid, are capable of complexing with metal ions, and especially metal ions in the II, III, IV, V and VI oxidation states, to form stable, water-soluble metal ion complexes in moderately alkaline to highly-acidic media. However, the complexing agents can be decomposed, under mild conditions, into non-organic compounds which, for many purposes are environmentally-nondamaging compounds thereby degrading the complex and releasing the metal ion for disposal or recovery. Uses for such complexing agents as well as methods for their manufacture are also described. 1 fig.

Extracting metal ions with diphosphonic acid, or derivative thereof

DOEpatents

Horwitz, Earl P.; Gatrone, Ralph C.; Nash, Kenneth L.

1994-01-01

Thermodynamically-unstable complexing agents which are diphosphonic acids and diphosphonic acid derivatives (or sulphur containing analogs), like carboxyhydroxymethanediphosphonic acid and vinylidene-1,1-diphosphonic acid, are capable of complexing with metal ions, and especially metal ions in the II, III, IV, V and VI oxidation states, to form stable, water-soluble metal ion complexes in moderately alkaline to highly-acidic media. However, the complexing agents can be decomposed, under mild conditions, into non-organic compounds which, for many purposes are environmentally-nondamaging compounds thereby degrading the complex and releasing the metal ion for disposal or recovery. Uses for such complexing agents as well as methods for their manufacture are also described.

Extracting metal ions with diphosphonic acid, or derivative thereof

DOEpatents

Horwitz, E.P.; Gatrone, R.C.; Nash, K.L.

1994-07-26

Thermodynamically-unstable complexing agents which are diphosphonic acids and diphosphonic acid derivatives (or sulfur containing analogs), like carboxyhydroxymethanediphosphonic acid and vinylidene-1,1-diphosphonic acid, are capable of complexing with metal ions, and especially metal ions in the II, III, IV, V and VI oxidation states, to form stable, water-soluble metal ion complexes in moderately alkaline to highly-acidic media. However, the complexing agents can be decomposed, under mild conditions, into non-organic compounds which, for many purposes are environmentally-nondamaging compounds thereby degrading the complex and releasing the metal ion for disposal or recovery. Uses for such complexing agents as well as methods for their manufacture are also described. 1 fig.

Cortical neurons and networks are dormant but fully responsive during isoelectric brain state.

PubMed

Altwegg-Boussac, Tristan; Schramm, Adrien E; Ballestero, Jimena; Grosselin, Fanny; Chavez, Mario; Lecas, Sarah; Baulac, Michel; Naccache, Lionel; Demeret, Sophie; Navarro, Vincent; Mahon, Séverine; Charpier, Stéphane

2017-09-01

A continuous isoelectric electroencephalogram reflects an interruption of endogenously-generated activity in cortical networks and systematically results in a complete dissolution of conscious processes. This electro-cerebral inactivity occurs during various brain disorders, including hypothermia, drug intoxication, long-lasting anoxia and brain trauma. It can also be induced in a therapeutic context, following the administration of high doses of barbiturate-derived compounds, to interrupt a hyper-refractory status epilepticus. Although altered sensory responses can be occasionally observed on an isoelectric electroencephalogram, the electrical membrane properties and synaptic responses of individual neurons during this cerebral state remain largely unknown. The aim of the present study was to characterize the intracellular correlates of a barbiturate-induced isoelectric electroencephalogram and to analyse the sensory-evoked synaptic responses that can emerge from a brain deprived of spontaneous electrical activity. We first examined the sensory responsiveness from patients suffering from intractable status epilepticus and treated by administration of thiopental. Multimodal sensory responses could be evoked on the flat electroencephalogram, including visually-evoked potentials that were significantly amplified and delayed, with a high trial-to-trial reproducibility compared to awake healthy subjects. Using an analogous pharmacological procedure to induce prolonged electro-cerebral inactivity in the rat, we could describe its cortical and subcortical intracellular counterparts. Neocortical, hippocampal and thalamo-cortical neurons were all silent during the isoelectric state and displayed a flat membrane potential significantly hyperpolarized compared with spontaneously active control states. Nonetheless, all recorded neurons could fire action potentials in response to intracellularly injected depolarizing current pulses and their specific intrinsic electrophysiological features were preserved. Manipulations of the membrane potential and intracellular injection of chloride in neocortical neurons failed to reveal an augmented synaptic inhibition during the isoelectric condition. Consistent with the sensory responses recorded from comatose patients, large and highly reproducible somatosensory-evoked potentials could be generated on the inactive electrocorticogram in rats. Intracellular recordings revealed that the underlying neocortical pyramidal cells responded to sensory stimuli by complex synaptic potentials able to trigger action potentials. As in patients, sensory responses in the isoelectric state were delayed compared to control responses and exhibited an elevated reliability during repeated stimuli. Our findings demonstrate that during prolonged isoelectric brain state neurons and synaptic networks are dormant rather than excessively inhibited, conserving their intrinsic properties and their ability to integrate and propagate environmental stimuli. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Novel one-pot synthesis of dicarboxylic acids mediated alginate-zirconium biopolymeric complex for defluoridation of water.

PubMed

Prabhu, Subbaiah Muthu; Meenakshi, Sankaran

2015-04-20

The present investigation explains the fluoride removal from aqueous solution using alginate-zirconium complex prepared with respective dicarboxylic acids like oxalic acid (Ox), malonic acid (MA) and succinic acid (SA) as a medium. The complexes viz., alginate-oxalic acid-zirconium (Alg-Ox-Zr), alginate-malonic acid-zirconium (Alg-MA-Zr) and alginate-succinic acid-zirconium (Alg-SA-Zr) were synthesized and studied for fluoride removal. The synthesized complexes were characterized by FTIR, XRD, SEM with EDAX and mapping images. The effects of various operating parameters were optimized. The result showed that the maximum removal of fluoride 9653mgF(-)/kg was achieved by Alg-Ox-Zr complex at acidic pH in an ambient atmospheric condition. Equilibrium data of Alg-Ox-Zr complex was fitted well with Freundlich isotherm. The calculated values of thermodynamic parameters indicated that the fluoride adsorption is spontaneous and endothermic in nature. The mechanism of fluoride removal behind Alg-Ox-Zr complex has been proposed in detail. The suitability of the Alg-Ox-Zr complex has been tested with the field sample collected in a nearby fluoride endemic area. Copyright © 2014 Elsevier Ltd. All rights reserved.

Preparation and investigation of acetyl salicylic acid-caffeine complex for rectal administration.

PubMed

Fouad, Ehab A; El-Badry, Mahmoud; Alanazi, Fars K; Arafah, Maha M; Al-Ashban, Riyadh; Alsarra, Ibrahim A

2010-06-01

An acetyl salicylic acid-caffeine complex was prepared and evaluated for the potential use in rectal administration. The results revealed the formation of a complex between acetyl salicylic acid and caffeine in a 1:1 molar ratio by a charge transfer mechanism. The effects of acetyl salicylic acid and complex on the rectal tissues showed destruction in the mucosal epithelium in case of acetyl salicylic acid; however, no change in the rectal tissues was noticed upon the administration of the complex. The effect of suppository bases on the release of the complex was studied using Witepsol H15 as fatty base and polyethylene glycols (PEG) 1000 and 4000 as a water soluble suppository base. The release profiles of acetyl salicylic acid and the complex were faster from PEG than from that of Witepsol H15. The percent release for the complex and acetyl salicylic acid from PEG base were 45.8, and 34.9%, respectively. However, it was 8.7 and 7.8%, respectively, from Witepsol H15 fatty base. The release kinetic was found to follow the non-Fickian diffusion model for complex from the suppository bases. It was concluded that acetyl salicylic acid caffeine complex can be used safely for rectal administration.

Preparation and investigation of acetyl salicylic acid-caffeine complex for rectal administration.

PubMed

Fouad, Ehab A; El-Badry, Mahmoud; Alanazi, Fars K; Arafah, Maha M; Al-Ashban, Riyadh; Alsarra, Ibrahim A

2009-07-30

An acetyl salicylic acid-caffeine complex was prepared and evaluated for the potential use in rectal administration. The results revealed the formation of a complex between acetyl salicylic acid and caffeine in a 1:1 molar ratio by a charge transfer mechanism. The effects of acetyl salicylic acid and complex on the rectal tissues showed destruction in the mucosal epithelium in case of acetyl salicylic acid; however, no change in the rectal tissues was noticed upon the administration of the complex. The effect of suppository bases on the release of the complex was studied using Witepsol H15 as fatty base and polyethylene glycols (PEG) 1000 and 4000 as a water soluble suppository base. The release profiles of acetyl salicylic acid and the complex were faster from PEG than from that of Witepsol H15. The percent release for the complex and acetyl salicylic acid from PEG base were 45.8, and 34.9%, respectively. However, it was 8.7 and 7.8%, respectively, from Witepsol H15 fatty base. The release kinetic was found to follow the non-Fickian diffusion model for complex from the suppository bases. It was concluded that acetyl salicylic acid caffeine complex can be used safely for rectal administration.

Systematic identification of genes involved in metabolic acid stress resistance in yeast and their potential as cancer targets.

PubMed

Shin, John J; Aftab, Qurratulain; Austin, Pamela; McQueen, Jennifer A; Poon, Tak; Li, Shu Chen; Young, Barry P; Roskelley, Calvin D; Loewen, Christopher J R

2016-09-01

A hallmark of all primary and metastatic tumours is their high rate of glucose uptake and glycolysis. A consequence of the glycolytic phenotype is the accumulation of metabolic acid; hence, tumour cells experience considerable intracellular acid stress. To compensate, tumour cells upregulate acid pumps, which expel the metabolic acid into the surrounding tumour environment, resulting in alkalization of intracellular pH and acidification of the tumour microenvironment. Nevertheless, we have only a limited understanding of the consequences of altered intracellular pH on cell physiology, or of the genes and pathways that respond to metabolic acid stress. We have used yeast as a genetic model for metabolic acid stress with the rationale that the metabolic changes that occur in cancer that lead to intracellular acid stress are likely fundamental. Using a quantitative systems biology approach we identified 129 genes required for optimal growth under conditions of metabolic acid stress. We identified six highly conserved protein complexes with functions related to oxidative phosphorylation (mitochondrial respiratory chain complex III and IV), mitochondrial tRNA biosynthesis [glutamyl-tRNA(Gln) amidotransferase complex], histone methylation (Set1C-COMPASS), lysosome biogenesis (AP-3 adapter complex), and mRNA processing and P-body formation (PAN complex). We tested roles for two of these, AP-3 adapter complex and PAN deadenylase complex, in resistance to acid stress using a myeloid leukaemia-derived human cell line that we determined to be acid stress resistant. Loss of either complex inhibited growth of Hap1 cells at neutral pH and caused sensitivity to acid stress, indicating that AP-3 and PAN complexes are promising new targets in the treatment of cancer. Additionally, our data suggests that tumours may be genetically sensitized to acid stress and hence susceptible to acid stress-directed therapies, as many tumours accumulate mutations in mitochondrial respiratory chain complexes required for their proliferation. © 2016. Published by The Company of Biologists Ltd.

Structure of β- N-dimethylamino-4-dodecyloxypropiophenone complexes with di- and polycarboxylic acids

NASA Astrophysics Data System (ADS)

Lebedeva, Tamara L.; Shandryuk, George A.; Sycheva, Tatyana I.; Bezborodov, Vladimir S.; Talroze, Raissa V.; Platé, Nicolai A.

1995-07-01

The type of bonds responsible for the complexation of di- and polyacids with the tertiary amine β- N-dimethylamino-4-dodecyloxypropiophenone is studied by means of FTIR spectroscopy. The complexes are shown to be stable due to strong H-bonding with partial charge transfer. The characteristic composition for complexes of polyacrylic, polymethacrylic and malonic acids is calculated as 2:1 (number of carboxylic groups per number of amine molecules) whereas glutaric acid forms complexes of different composition including 1:1. The characteristic composition results from the structure of the initial acid. The structures of both the characteristic complex and "excess" acid are also discussed.

Quantitative detection of pathogens in centrifugal microfluidic disks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koh, Chung-Yan; Schaff, Ulrich Y.; Sommer, Gregory Jon

A system and methods for detection of a nucleic acid including forming a plurality of nucleic acid detection complexes are described, each of the complexes including a nucleic acid analyte, a detection agent and a functionalized probe. The method further including binding the nucleic acid detection complexes to a plurality of functionalized particles in a fluid sample and separating the functionalized particles having the nucleic acid detection complexes bound thereto from the fluid sample using a density media. The nucleic acid analyte is detected by detecting the detection agent.

[Significance of CRF and dopamine receptors in amygdala for reinforcing effects of opiates and opioids on self-stimulation of lateral hypothalamus in rats].

PubMed

Shabanov, P D; Lebedev, A A; Liubimov, A V; Kornilov, V A

2011-01-01

Bipolar electrodes were implanted in the lateral hypothalamus in a group of 44 Wistar male rats in order to study self-stimulation reaction in the Skinner box. Simultaneously, microcanules were implanted into the central nucleus of the amygdala to inject the drugs (1 microl per injection). The blockade of corticoliberin (CRF) receptors (astressin, 1 microg) or Na+influx currents (xycaine or lidocain 1 microg) by the intrastructural administration of drugs into the amygdala decreased self-stimulation reaction of the lateral hypothalamus in rats by 29-55%. The inhibition of D1 and D2 dopamine receptors in the amygdala with SCH23390 (1 microg) or sulpiride (1 microg) respectively, also reduced self-stimulation but to a lower degree. On the background of blockade of CRF (astressin) and dopamine (sulpiride) receptors as well as sodium influx ionic currents (lidocain) in the amygdala neurons, psychomotor stimulant amphetamine (1 mg/kg) and barbiturate sodium ethaminal (5 mg/kg) retained their psychoactivating effect on self-stimulation (+30-37%), while fentanyl (0.1 mg/kg) and leu-enkephaline (0.1 mg/kg) did not produce this effect. Fentanyl moderately activated self-stimulation only after the blockade of D1 dopamine receptors with SCH23390. After the blockade of CRF receptors, leu-enkephaline strengthened its depressant effect on self-stimulation reaction (-89%). Therefore, if the modulating action of amygdala on the hypothalamus is eliminated, the enhancing effects of opiates (fentanyl) and opioids (leu-encephaline) are blocked, but the effects of psychomotor stimulant amphetamine and barbiturate sodium ethaminal are retained.

Antinociceptive and antiallodynic effects of Momordica charantia L. in tibial and sural nerve transection-induced neuropathic pain in rats.

PubMed

Jain, Vivek; Pareek, Ashutosh; Paliwal, Nishant; Ratan, Yashumati; Jaggi, Amteshwar Singh; Singh, Nirmal

2014-02-01

This study was designed to investigate the ameliorative potential of Momordica charantia L. (MC) in tibial and sural nerve transection (TST)-induced neuropathic pain in rats. TST was performed by sectioning tibial and sural nerve portions (2 mm) of the sciatic nerve, and leaving the common peroneal nerve intact. Acetone drop, pin-prick, hot plate, paint-brush, and walking track tests were performed to assess cold allodynia, mechanical and heat hyperalgesia, and dynamic mechanical allodynia and tibial functional index, respectively. The levels of tumour necrosis factor (TNF)-alpha and thio-barbituric acid reactive substances (TBARS) were measured in the sciatic nerve as an index of inflammation and oxidative stress. MC (all doses, orally, once daily) was administered to the rats for 24 consecutive days. TST led to significant development of cold allodynia, mechanical and heat hyperalgesia, dynamic mechanical allodynia, and functional deficit in walking along with rise in the levels of TBARS and TNF-alpha. Administration of MC (200, 400, and 800 mg/kg) significantly attenuated TST-induced behavioural and biochemical changes. Furthermore, pretreatment of BADGE (120 mg/kg, intraperitoneally) abolished the protective effect of MC in TST-induced neuropathic pain. Collectively, it is speculated that PPAR-gamma agonistic activity, anti-inflammatory, and antioxidative potential is critical for antinociceptive effect of MC in neuropathic pain.

Surface reactions of iron - enriched smectites: adsorption and transformation of hydroxy fatty acids and phenolic acids

NASA Astrophysics Data System (ADS)

Polubesova, Tamara; Olshansky, Yaniv; Eldad, Shay; Chefetz, Benny

2014-05-01

Iron-enriched smectites play an important role in adsorption and transformation of soil organic components. Soil organo-clay complexes, and in particular humin contain hydroxy fatty acids, which are derived from plant biopolymer cutin. Phenolic acids belong to another major group of organic acids detected in soil. They participate in various soil processes, and are of concern due to their allelopathic activity. We studied the reactivity of iron-enriched smectites (Fe(III)-montmorillonite and nontronite) toward both groups of acids. We used fatty acids- 9(10),16-dihydroxypalmitic acid (diHPA), isolated from curtin, and 9,10,16-trihydroxypalmitic acid (triHPA); the following phenolic acids were used: ferulic, p-coumaric, syringic, and vanillic. Adsorption of both groups of acids was measured. The FTIR spectra of fatty acid-mineral complexes indicated inner-sphere complexation of fatty acids with iron-enriched smectites (versus outer-sphere complexation with Ca(II)-montmorillonite). The LC-MS results demonstrated enhanced esterification of fatty acids on the iron-enriched smectite surfaces (as compared to Ca(II)-montmorillonite). This study suggests that fatty acids can be esterified on the iron-enriched smectite surfaces, which results in the formation of stable organo-mineral complexes. These complexes may serve as a model for the study of natural soil organo-clay complexes and humin. The reaction of phenolic acids with Fe(III)-montmorillonite demonstrated their oxidative transformation by the mineral surfaces, which was affected by molecular structure of acids. The following order of their transformation was obtained: ferulic >syringic >p-coumaric >vanillic. The LC-MS analysis demonstrated the presence of dimers, trimers, and tetramers of ferulic acid on the surface of Fe(III)-montmorillonite. Oxidation and transformation of ferulic acid were more intense on the surface of Fe(III)-montmorillonite as compared to Fe(III) in solution due to stronger complexation on the Fe(III)-motnomrillonite surface. Our study demonstrate the importance of iron-enriched minerals for the abiotic formation of humic materials and for the transformation of aromatic (phenolic) pollutants.

40 CFR 721.10089 - Modified salicylic acid, zirconium complex (generic).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Modified salicylic acid, zirconium... Specific Chemical Substances § 721.10089 Modified salicylic acid, zirconium complex (generic). (a) Chemical... as modified salicylic acid, zirconium complex (PMN P-00-552) is subject to reporting under this...

40 CFR 721.10089 - Modified salicylic acid, zirconium complex (generic).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Modified salicylic acid, zirconium... Specific Chemical Substances § 721.10089 Modified salicylic acid, zirconium complex (generic). (a) Chemical... as modified salicylic acid, zirconium complex (PMN P-00-552) is subject to reporting under this...

Complexation and molecular modeling studies of europium(III)-gallic acid-amino acid complexes.

PubMed

Taha, Mohamed; Khan, Imran; Coutinho, João A P

2016-04-01

With many metal-based drugs extensively used today in the treatment of cancer, attention has focused on the development of new coordination compounds with antitumor activity with europium(III) complexes recently introduced as novel anticancer drugs. The aim of this work is to design new Eu(III) complexes with gallic acid, an antioxida'nt phenolic compound. Gallic acid was chosen because it shows anticancer activity without harming health cells. As antioxidant, it helps to protect human cells against oxidative damage that implicated in DNA damage, cancer, and accelerated cell aging. In this work, the formation of binary and ternary complexes of Eu(III) with gallic acid, primary ligand, and amino acids alanine, leucine, isoleucine, and tryptophan was studied by glass electrode potentiometry in aqueous solution containing 0.1M NaNO3 at (298.2 ± 0.1) K. Their overall stability constants were evaluated and the concentration distributions of the complex species in solution were calculated. The protonation constants of gallic acid and amino acids were also determined at our experimental conditions and compared with those predicted by using conductor-like screening model for realistic solvation (COSMO-RS) model. The geometries of Eu(III)-gallic acid complexes were characterized by the density functional theory (DFT). The spectroscopic UV-visible and photoluminescence measurements are carried out to confirm the formation of Eu(III)-gallic acid complexes in aqueous solutions. Copyright © 2016 Elsevier Inc. All rights reserved.

Interaction of metal ions and amino acids - Possible mechanisms for the adsorption of amino acids on homoionic smectite clays

NASA Technical Reports Server (NTRS)

Gupta, A.; Loew, G. H.; Lawless, J.

1983-01-01

A semiempirical molecular orbital method is used to characterize the binding of amino acids to hexahydrated Cu(2+) and Ni(2+), a process presumed to occur when they are adsorbed in the interlamellar space of homoionic smectite clays. Five alpha-amino acids, beta-alanine, and gamma-aminobutyric acid were used to investigate the metal ion and amino acid specificity in binding. It was assumed that the alpha, beta, and gamma-amino acids would bind as bidentate anionic ligands, forming either 1:1 or 1:2 six-coordinated five, six, and seven-membered-ring chelate complexes, respectively. Energies of complex formation, optimized geometries, and electron and spin distribution were determined; and steric constraints of binding of the amino acids to the ion-exchanged cations in the interlamellar spacing of a clay were examined. Results indicate that hexahydrated Cu(2+) forms more stable complexes than hexahydrated Ni(2+) with all the amino acids studied. However, among these amino acids, complex formation does not favor the adsorption of the biological subset. Calculated energetics of complex formation and steric constraints are shown to predict that 1:1 rather than 1:2 metal-amino acid complexes are generally favored in the clay.

Solid-state acid-base interactions in complexes of heterocyclic bases with dicarboxylic acids: crystallography, hydrogen bond analysis, and 15N NMR spectroscopy.

PubMed

Li, Z Jane; Abramov, Yuriy; Bordner, Jon; Leonard, Jason; Medek, Ales; Trask, Andrew V

2006-06-28

A cancer candidate, compound 1, is a weak base with two heterocyclic basic nitrogens and five hydrogen-bonding functional groups, and is sparingly soluble in water rendering it unsuitable for pharmaceutical development. The crystalline acid-base pairs of 1, collectively termed solid acid-base complexes, provide significant increases in the solubility and bioavailability compared to the free base, 1. Three dicarboxylic acid-base complexes, sesquisuccinate 2, dimalonate 3, and dimaleate 4, show the most favorable physicochemical profiles and are studied in greater detail. The structural analyses of the three complexes using crystal structure and solid-state NMR reveal that the proton-transfer behavior in these organic acid-base complexes vary successively correlating with Delta pKa. As a result, 2 is a neutral complex, 3 is a mixed ionic and zwitterionic complex and 4 is an ionic salt. The addition of the acidic components leads to maximized hydrogen bond interactions forming extended three-dimensional networks. Although structurally similar, the packing arrangements of the three complexes are considerably different due to the presence of multiple functional groups and the flexible backbone of 1. The findings in this study provide insight into the structural characteristics of complexes involving heterocyclic bases and carboxylic acids, and demonstrate that X-ray crystallography and 15N solid-state NMR are truly complementary in elucidating hydrogen bonding interactions and the degree of proton transfer of these complexes.

Proceedings of the drug testing laboratory managers symposium, 28 January--1 February 1974. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Noe, E.R.; Romanchick, W.A.; Ainsworth, C.A. III

1975-06-01

This report deals with broad concepts of managing mass screening programs for drugs of abuse; e.g., morphine, barbiturate, amphetamine, cocaine, and methaqualone. The interactions of the screening process and of the rehabilitation program were covered. Psychotherapy and group therapy are both utilized in rehabilitation programs. The semiautomated radioimmunoassay (RIA) screening procedures are both sensitive and specific at nanogram quantities. Future evaluations of a wafer disk transferral system and of a latex test for morphine are presented. The unique quality control system employed by military drug abuse testing laboratories is discussed. (Author) (GRA)

Effectiveness of lorazepam-assisted interviews in an adolescent with dissociative amnesia: A case report★

PubMed Central

Seo, Yuna; Shin, Mi-Hee; Kim, Sung-Gon; Kim, Ji-Hoon

2013-01-01

To facilitate gathering information during a psychiatric interview, some psychiatrists advocate augmenting the interview using drugs. Rather than barbiturates, benzodiazepines have been used for drug-assisted interviews. Dissociative amnesia is one of the indications for these interviews. Herein, we present the case of a 15-year-old female who was diagnosed as having dissociative amnesia because of conflicts with her friends. She was administered a lorazepam-assisted interview to aid recovery of her memories. In this case, a small dose of lorazepam was sufficient to recover her memories without any adverse effects. PMID:25206490

Effectiveness of lorazepam-assisted interviews in an adolescent with dissociative amnesia: A case report.

PubMed

Seo, Yuna; Shin, Mi-Hee; Kim, Sung-Gon; Kim, Ji-Hoon

2013-01-15

To facilitate gathering information during a psychiatric interview, some psychiatrists advocate augmenting the interview using drugs. Rather than barbiturates, benzodiazepines have been used for drug-assisted interviews. Dissociative amnesia is one of the indications for these interviews. Herein, we present the case of a 15-year-old female who was diagnosed as having dissociative amnesia because of conflicts with her friends. She was administered a lorazepam-assisted interview to aid recovery of her memories. In this case, a small dose of lorazepam was sufficient to recover her memories without any adverse effects.

A study of pre-operative sedatives

PubMed Central

Parkhouse, James; Mahoney, Joan

1968-01-01

A state-registered nurse acted as a whole-time investigator following patients through the pre-operative night in hospital and questioning them in the morning, to assess the relative merits of different medications. Two new sedatives were compared with a standard barbiturate and a placebo, and information was collected from patients who elected to have no medication to help them sleep. Subjective assessment enabled the placebo to be distinguished from the active medications, although there was little difference between these. The importance of psychological factors is discussed in relation to those patients who had no medication. PMID:4869880

[Humus composition of black soil and its organo-mineral complexes under different fertility level].

PubMed

Zhao, Lanpo; Wang, Jie; Liu, Jingshuan; Liu, Shuxia; Wang, Yanling; Wang, Hongbin; Zhang, Zhidan

2005-01-01

Determinations by Kumada method showed that with the improvement of black soil fertility, the free and combined humus contents in soil and its different size organo-mineral complexes increased, but the humification degree of free humus decreased, which was more obvious in silt and fine sand size complexes. The organic carbon content in complexes, humus extraction rate, free humus content, and humification degree of free humic acid decreased with the increasing particle size of complexes. All free humic acids in fertile soil were Rp type, while in unfertile soil, they were Rp and B type. With the increasing particle size of complexes, the type of free humic acids changed in the sequence A type (clay)-->B type (silt)-->Rp type (fine sand). Combined form humic acid mainly belonged to A type, no matter what particle size the complex was. The improvement of soil fertility could make the humification degree of free humus in soil and its complexes decrease, and furthermore, result in type change. In black soil, the type change of free humic acid mainly occurred in silt size complex, and that of combined form humic acid mainly occurred in fine sand size complex.

Detection and isolation of nucleic acid sequences using competitive hybridization probes

DOEpatents

Lucas, Joe N.; Straume, Tore; Bogen, Kenneth T.

1997-01-01

A method for detecting a target nucleic acid sequence in a sample is provided using hybridization probes which competitively hybridize to a target nucleic acid. According to the method, a target nucleic acid sequence is hybridized to first and second hybridization probes which are complementary to overlapping portions of the target nucleic acid sequence, the first hybridization probe including a first complexing agent capable of forming a binding pair with a second complexing agent and the second hybridization probe including a detectable marker. The first complexing agent attached to the first hybridization probe is contacted with a second complexing agent, the second complexing agent being attached to a solid support such that when the first and second complexing agents are attached, target nucleic acid sequences hybridized to the first hybridization probe become immobilized on to the solid support. The immobilized target nucleic acids are then separated and detected by detecting the detectable marker attached to the second hybridization probe. A kit for performing the method is also provided.

Facile regio- and stereoselective hydrometalation of alkynes with a combination of carboxylic acids and group 10 transition metal complexes: selective hydrogenation of alkynes with formic acid.

PubMed

Shen, Ruwei; Chen, Tieqiao; Zhao, Yalei; Qiu, Renhua; Zhou, Yongbo; Yin, Shuangfeng; Wang, Xiangbo; Goto, Midori; Han, Li-Biao

2011-10-26

A facile, highly stereo- and regioselective hydrometalation of alkynes generating alkenylmetal complex is disclosed for the first time from a reaction of alkyne, carboxylic acid, and a zerovalent group 10 transition metal complex M(PEt(3))(4) (M = Ni, Pd, Pt). A mechanistic study showed that the hydrometalation does not proceed via the reaction of alkyne with a hydridometal generated by the protonation of a carboxylic acid with Pt(PEt(3))(4), but proceeds via a reaction of an alkyne coordinate metal complex with the acid. This finding clarifies the long proposed reaction mechanism that operates via the generation of an alkenylpalladium intermediate and subsequent transformation of this complex in a variety of reactions catalyzed by a combination of Brϕnsted acid and Pd(0) complex. This finding also leads to the disclosure of an unprecedented reduction of alkynes with formic acid that can selectively produce cis-, trans-alkenes and alkanes by slightly tuning the conditions.

Detection and isolation of nucleic acid sequences using competitive hybridization probes

DOEpatents

Lucas, J.N.; Straume, T.; Bogen, K.T.

1997-04-01

A method for detecting a target nucleic acid sequence in a sample is provided using hybridization probes which competitively hybridize to a target nucleic acid. According to the method, a target nucleic acid sequence is hybridized to first and second hybridization probes which are complementary to overlapping portions of the target nucleic acid sequence, the first hybridization probe including a first complexing agent capable of forming a binding pair with a second complexing agent and the second hybridization probe including a detectable marker. The first complexing agent attached to the first hybridization probe is contacted with a second complexing agent, the second complexing agent being attached to a solid support such that when the first and second complexing agents are attached, target nucleic acid sequences hybridized to the first hybridization probe become immobilized on to the solid support. The immobilized target nucleic acids are then separated and detected by detecting the detectable marker attached to the second hybridization probe. A kit for performing the method is also provided. 7 figs.

Starch-lipid complexes: Interesting material and applications from amylose-fatty acid salt inclusion complexes

USDA-ARS?s Scientific Manuscript database

Aqueous slurries of high amylose starch can be steam jet cooked and blended with aqueous solutions of fatty acid salts to generate materials that contain inclusion complexes between amylose and the fatty acid salt. These complexes are simply prepared on large scale using commercially available steam...

Locating the binding sites of folic acid with milk α- and β-caseins.

PubMed

Bourassa, P; Tajmir-Riahi, H A

2012-01-12

We located the binding sites of folic acid with milk α- and β-caseins at physiological conditions, using constant protein concentration and various folic acid contents. FTIR, UV-visible, and fluorescence spectroscopic methods as well as molecular modeling were used to analyze folic acid binding sites, the binding constant, and the effect of folic acid interaction on the stability and conformation of caseins. Structural analysis showed that folic acid binds caseins via both hydrophilic and hydrophobic contacts with overall binding constants of K(folic acid-α-caseins) = 4.8 (±0.6) × 10(4) M(-1) and K(folic acid-β-caseins) = 7.0 (±0.9) × 10(4) M(-1). The number of bound acid molecules per protein was 1.5 (±0.4) for α-casein and 1.4 (±0.3) for β-casein complexes. Molecular modeling showed different binding sites for folic acid on α- and β-caseins. The participation of several amino acids in folic acid-protein complexes was observed, which was stabilized by hydrogen bonding network and the free binding energy of -7.7 kcal/mol (acid-α-casein) and -8.1 kcal/mol (acid-β-casein). Folic acid complexation altered protein secondary structure by the reduction of α-helix from 35% (free α-casein) to 33% (acid-complex) and 32% (free β-casein) to 26% (acid-complex) indicating a partial protein destabilization. Caseins might act as carriers for transportation of folic acid to target molecules.

Complex formation equilibria of binary and ternary complexes involving 3,3-bis(1-methylimidazol-2yl)propionic acid and bio-relevant ligands as 1-aminocyclopropane carboxylic acid with reference to plant hormone

NASA Astrophysics Data System (ADS)

Shoukry, Mohamed M.; Hassan, Safaa S.

2014-01-01

The formation equilibria for the binary complexes of Cu(II) with 1-aminocyclopropane carboxylic acid (ACC) and 3,3-bis(1-methylimidazol-2-yl)propionic acid (BIMP) were investigated. ACC and BIMP form the complexes 1 1 0, 1 2 0 and 1 1 -1. The ternary complexes of Cu(II) with BIMP and biorelevant ligands as some selected amino acids, peptides and DNA constituents are formed in a stepwise mechanism. The stability constants of the complexes formed were determined and their distribution diagrams were evaluated. The kinetics of hydrolysis of glycine methyl ester in presence of [Cu(BIMP)]+ was investigated by pH-stat technique and the mechanism was discussed.

Spectra, energy levels, and energy transition of lanthanide complexes with cinnamic acid and its derivatives

NASA Astrophysics Data System (ADS)

Zhou, Kaining; Feng, Zhongshan; Shen, Jun; Wu, Bing; Luo, Xiaobing; Jiang, Sha; Li, Li; Zhou, Xianju

2016-04-01

High resolution spectra and luminescent lifetimes of 6 europium(III)-cinnamic acid complex {[Eu2L6(DMF)(H2O)]·nDMF·H2O}m (L = cinnamic acid I, 4-methyl-cinnamic acid II, 4-chloro-cinnamic acid III, 4-methoxy-cinnamic acid IV, 4-hydroxy-cinnamic acid V, 4-nitro-cinnamic acid VI; DMF = N, N-dimethylformamide, C3H7NO) were recorded from 8 K to room temperature. The energy levels of Eu3 + in these 6 complexes are obtained from the spectra analysis. It is found that the energy levels of the central Eu3 + ions are influenced by the nephelauxetic effect, while the triplet state of ligand is lowered by the p-π conjugation effect of the para-substituted functional groups. The best energy matching between the ligand triplet state and the central ion excited state is found in complex I. While the other complexes show poorer matching because the gap of 5D0 and triplet state contracts.

THE SOLVENT EXTRACTION OF NITROSYLRUTHENIUM BY TRILAURYLAMINE IN NITRATE SYSTEM. Summary Report for the Period, July 1, 1960 to March 31, 1962

DOE Office of Scientific and Technical Information (OSTI.GOV)

Skavdahl, R.E.; Mason, E.A.

1962-06-01

An investigation of the solvent extraction characteristics of the nitro and nitrato complexes of nitrosylruthenium in nitric acid- sodium nitrate aqueous media was conducted. As the organic extractant phase, a solution of trilaurylamine (TLA) in toluene was utilized. In addition to the usual process parameter variation tyne of experiment, a rapid dilution type of experiment was used extensively to determine qualitative and semiquantitative results regarding the degree of extractability and concentration of the more extractable species of the nitrato complexes of nitrosylruthenium. It was found that the acids of the tetra-nitrato and pentanitrato complexes were the more extractable species formore » that set of complexes and that the acid of the penta-nitrato complex was the more extractable of the two. It was observed that for freshly prepared solutions, the dinitro complex of nitrosylruthenium was much more extractable than the gross nitrato complexes solutions. Nitro complexes in general, and the dinitro complex in particular, may be the controlling agent in ruthenium decontamination of spent nuclear fuel processed by solvent extraction methods. The experimental results from both sets of complexes could be more meaningfully correlated on the basis of unbound nitric acid concentration in the organic phase than on the basis of nitric acid concentration in the aqueous phase. The extraction of nitric acid by TLA from nitric acid-sodium nitrate aqueous solutions was investigated and the results correlated on the basis of activity of the undissociated nitric acid in the aqueous phase. (auth)« less

Antiurolithiatic Effect of Sirupeelai Samoola Kudineer: A Polyherbal Siddha Decoction on Ethylene Glycol-induced Renal Calculus in Experimental Rats

PubMed Central

Vasanthi, A. Hannah Rachel; Muthulakshmi, V.; Gayathri, V.; Manikandan, R.; Ananthi, S.; Kuruvilla, Sarah

2017-01-01

Background: Sirupeelai Samoola Kudineer (SK), a polyherbal decoction containing four medicinal plants has been used in Siddha system of medicine, practiced in Southern parts of India for the management of urolithiasis. Objective: The present study is carried out to scientifically validate the traditional claim and to study the mechanism of action of the drug. Materials and Methods: In the present study, anti-urolithiatic effect of SK was evaluated in Sprague-Dawley rats using ethylene glycol through drinking water and intraperitoneal injection of sodium oxalate. Renal damage was confirmed by the increased production of thiobarbituric acid reactive substance (TBARS). Results: Co-treatment with SK to urolithiatic rats for 21 days significantly prevented the elevation of renal and urinary stone biomarkers in plasma and renal tissue thereby preventing renal damage and the formation of renal calculi. Administration of SK at all doses and cystone restored the antioxidant (glutathione) levels by preventing the elevation of TBARS in the kidney tissue, which was further confirmed by histological sections. Conclusions: SK treatment promotes diuresis which leads to flushing of the renal stones and maintains the alkaline environment in the urinary system which probably mediates the antilithiatic activity. SK provides structural and functional protection to the kidneys by enhancing its physiological function against stone formation and validates its clinical use. SUMMARY SK exhibited antilithiatic and diuretic potential in ethylene glycol and sodium oxalate induced urolithiasis in ratsElevated urinary stone markers (Calcium, oxalate, uric acid, magnesium and phosphates) in plasma and renal tubular enzymes (LDH, GGT, ALP, AST ALT) in urolithiatic rats were reversed by SK treatmentSK administration significantly reduced the level of renal stress markers like Urea, Creatinine, LPO and elevated SOD, GPx, GSH levels aiding in nephroprotectionSK also provides structural and functional protection against ethylene glycol- induced renal calculus in rats as evidenced by histopathological studies. Abbreviations used: SK: Sirupeelai Samoola Kudineer; TBARS: ThioBarbituric Acid Reactive Substances; SOD: SuperOxide Dismutase; GPx: Gluthathione peroxidase; GSH- Glutathione; LPO: Lipid peroxidation as measured as TBARS; AST: Aspartate AminoTransferase; ALT: Alanine Amino transferase; GGT: Gamma Glutamyl Transferase; LDH: Lactate Dehydrogenase. PMID:28808392

Regulation of Fatty Acid Oxidation in Mouse Cumulus-Oocyte Complexes during Maturation and Modulation by PPAR Agonists

PubMed Central

Dunning, Kylie R.; Anastasi, Marie R.; Zhang, Voueleng J.; Russell, Darryl L.; Robker, Rebecca L.

2014-01-01

Fatty acid oxidation is an important energy source for the oocyte; however, little is known about how this metabolic pathway is regulated in cumulus-oocyte complexes. Analysis of genes involved in fatty acid oxidation showed that many are regulated by the luteinizing hormone surge during in vivo maturation, including acyl-CoA synthetases, carnitine transporters, acyl-CoA dehydrogenases and acetyl-CoA transferase, but that many are dysregulated when cumulus-oocyte complexes are matured under in vitro maturation conditions using follicle stimulating hormone and epidermal growth factor. Fatty acid oxidation, measured as production of 3H2O from [3H]palmitic acid, occurs in mouse cumulus-oocyte complexes in response to the luteinizing hormone surge but is significantly reduced in cumulus-oocyte complexes matured in vitro. Thus we sought to determine whether fatty acid oxidation in cumulus-oocyte complexes could be modulated during in vitro maturation by lipid metabolism regulators, namely peroxisome proliferator activated receptor (PPAR) agonists bezafibrate and rosiglitazone. Bezafibrate showed no effect with increasing dose, while rosiglitazone dose dependently inhibited fatty acid oxidation in cumulus-oocyte complexes during in vitro maturation. To determine the impact of rosiglitazone on oocyte developmental competence, cumulus-oocyte complexes were treated with rosiglitazone during in vitro maturation and gene expression, oocyte mitochondrial activity and embryo development following in vitro fertilization were assessed. Rosiglitazone restored Acsl1, Cpt1b and Acaa2 levels in cumulus-oocyte complexes and increased oocyte mitochondrial membrane potential yet resulted in significantly fewer embryos reaching the morula and hatching blastocyst stages. Thus fatty acid oxidation is increased in cumulus-oocyte complexes matured in vivo and deficient during in vitro maturation, a known model of poor oocyte quality. That rosiglitazone further decreased fatty acid oxidation during in vitro maturation and resulted in poor embryo development points to the developmental importance of fatty acid oxidation and the need for it to be optimized during in vitro maturation to improve this reproductive technology. PMID:24505284

Hydride-Meisenheimer Complex Formation and Protonation as Key Reactions of 2,4,6-Trinitrophenol Biodegradation by Rhodococcus erythropolis

PubMed Central

Rieger, Paul-Gerhard; Sinnwell, Volker; Preuß, Andrea; Francke, Wittko; Knackmuss, Hans-Joachim

1999-01-01

Biodegradation of 2,4,6-trinitrophenol (picric acid) by Rhodococcus erythropolis HLPM-1 proceeds via initial hydrogenation of the aromatic ring system. Here we present evidence for the formation of a hydride-Meisenheimer complex (anionic ς-complex) of picric acid and its protonated form under physiological conditions. These complexes are key intermediates of denitration and productive microbial degradation of picric acid. For comparative spectroscopic identification of the hydride complex, it was necessary to synthesize this complex for the first time. Spectroscopic data revealed the initial addition of a hydride ion at position 3 of picric acid. This hydride complex readily picks up a proton at position 2, thus forming a reactive species for the elimination of nitrite. Cell extracts of R. erythropolis HLPM-1 transform the chemically synthesized hydride complex into 2,4-dinitrophenol. Picric acid is used as the sole carbon, nitrogen, and energy source by R. erythropolis HLPM-1. PMID:9973345

The behavior and importance of lactic acid complexation in Talspeak extraction systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grimes, Travis S.; Nilsson, Mikael; Nash, Kenneth L.

2008-07-01

Advanced partitioning of spent nuclear fuel in the UREX +la process relies on the TALSPEAK process for separation of fission-product lanthanides from trivalent actinides. The classic TALSPEAK utilizes an aqueous medium of both lactic acid and diethylenetriaminepentaacetic acid and the extraction reagent di(2-ethylhexyl)phosphoric acid in an aromatic diluent. In this study, the specific role of lactic acid and the complexes involved in the extraction of the trivalent actinides and lanthanides have been investigated using {sup 14}C-labeled lactic acid. Our results show that lactic acid partitions between the phases in a complex fashion. (authors)

Barbiturate Induction for the Prevention of Emergence Agitation after Pediatric Sevoflurane Anesthesia

PubMed Central

Nakahara, Haruna; Kimoto, Ayako; Beppu, Yuki; Yoshimura, Maki; Kojima, Toshiyuki; Fukano, Taku

2015-01-01

OBJECTIVES: Emergence agitation (EA) is a common and troublesome problem in pediatric patients recovering from general anesthesia. The incidence of EA is reportedly higher after general anesthesia maintained with sevoflurane, a popular inhalational anesthetic agent for pediatric patients. We conducted this prospective, randomized, double-blind study to test the effect of an intravenous ultra-short–acting barbiturate, thiamylal, administered during induction of general anesthesia on the incidence and severity of EA in pediatric patients recovering from Sevoflurane anesthesia. METHODS: Fifty-four pediatric patients (1 to 6 years of age) undergoing subumbilical surgeries were randomized into 2 groups. Patients received either intravenous thiamylal 5mg/kg (Group T) or inhalational Sevoflurane 5% (Group S) as an anesthetic induction agent. Following induction, general anesthesia was maintained with Sevoflurane and nitrous oxide (N2O) in both groups. To control the intra- and post-operative pain, caudal block or ilioinguinal/iliohypogastric block was performed. The incidence and severity of EA were evaluated by using the Modified Objective Pain Scale (MOPS: 0 to 6) at 15 and 30 min after arrival in the post-anesthesia care unit (PACU). RESULTS: Fifteen minutes after arrival in the PACU, the incidence of EA in Group T (28%) was significantly lower than in Group S (64%; p = 0.023) and the MOPS in Group T (median 0, range 0 to 6) was significantly lower than in Group S (median 4, range 0 to 6; p = 0.005). The interval from discontinuation of Sevoflurane to emergence from anesthesia was not significantly different between the 2 groups. CONCLUSIONS: Thiamylal induction reduced the incidence and severity of EA in pediatric patients immediately after Sevoflurane anesthesia. PMID:26472953

Epidemiology of overdose episodes from the period prior to hospitalization for drug poisoning until discharge in Japan: An exploratory descriptive study using a nationwide claims database.

PubMed

Okumura, Yasuyuki; Sakata, Nobuo; Takahashi, Kunihiko; Nishi, Daisuke; Tachimori, Hisateru

2017-08-01

Little is known about the nationwide epidemiology of the annual rate, causative substance, and clinical course of overdose-related admission. We aimed to describe the epidemiology of overdose episodes from the period prior to hospitalization for drug poisoning until discharge to home. We assessed all cases of admission due to overdose (21,663 episodes) in Japan from October 2012 through September 2013 using the National Database of Health Insurance Claims and Specific Health Checkups of Japan. The annual rate of overdose admission was 17.0 per 100,000 population. Women exhibited two peaks in admission rates at 19-34 years (40.9 per 100,000) and ≥75 years (27.8 per 100,000). Men exhibited one peak in the admission rate at ≥75 years (23.7 per 100,000). Within 90 days prior to overdose, ≥60% and ≥9% of patients aged 19-49 years received a prescription for benzodiazepines and barbiturates, respectively. In addition, 59% of patients aged ≥75 years received a prescription for benzodiazepines prior to overdose, 47% had a history of congestive heart failure, and 24% had a diagnosis of poisoning by cardiovascular drugs. The proportion of patients with recent psychiatric treatments decreased with age (65.1% in those aged 35-49 years and 13.9% in those aged ≥75 years). The findings emphasize the need for overdose prevention programs that focus on psychiatric patients aged 19-49 years who are prescribed benzodiazepines or barbiturates and on non-psychiatric patients aged ≥75 years who are prescribed benzodiazepines or digitalis. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

Phenobarbital blockade of the preovulatory luteinizing hormone surge: association with phase-advanced circadian clock and altered suprachiasmatic nucleus Period1 gene expression

PubMed Central

Legan, Sandra J.; Donoghue, Kathleen M.; Franklin, Kathleen M.; Duncan, Marilyn J.

2009-01-01

The suprachiasmatic nucleus (SCN) controls the timing of the preovulatory luteinizing hormone (LH) surge in laboratory rodents. Barbiturate administration during a critical period on proestrus delays the surge and prolongs the estrous cycle 1 day. Because a nonphotic timing signal (zeitgeber) during the critical period that phase advances activity rhythms can also induce the latter effect, we hypothesized that barbiturates delay the LH surge by phase-advancing its circadian timing signal beyond the critical period. In experiment 1, locomotor rhythms and estrous cycles were monitored in hamsters for 2–3 wk preinjection and postinjection of vehicle or phenobarbital and after transfer to darkness at zeitgeber time (ZT) 6 on proestrus. Phenobarbital delayed estrous cycles in five of seven hamsters, which exhibited phase shifts that averaged twofold greater than those exhibited by vehicle controls or phenobarbital-injected hamsters with normal cycles. Experiment 2 used a similar protocol, but injections were at ZT 5, and blood samples for LH determination were collected from 1200 to 1800 on proestrus and the next day via jugular cannulae inserted the day before proestrus. Phenobarbital delayed the LH surge 1 day in all six hamsters, but it occurred at an earlier circadian time, supporting the above hypothesis. Experiment 3 investigated whether phenobarbital, like other nonphotic zeitgebers, suppresses SCN Period1 and Period2 transcription. Two hours postinjection, phenobarbital decreased SCN expression of only Period1 mRNA, as determined by in situ hybridization. These results suggest that phenobarbital advances the SCN pacemaker, governing activity rhythms and hormone release in part by decreasing its Period1 gene expression. PMID:19297538

Phenytoin: 80 years young, from epilepsy to breast cancer, a remarkable molecule with multiple modes of action.

PubMed

Keppel Hesselink, Jan M; Kopsky, David J

2017-08-01

In 1908 phenytoin (5,5-diphenylhydantoin) was first synthesized as a barbiturate derivative in Germany by professor Heinrich Biltz (1865-1943) and subsequently resynthesized by an American chemist of the pharmaceutical company Parke-Davis in 1923 in Detroit. Screening phenytoin did not reveal comparable sedative side effects as barbiturates and, thus, Parke-Davis discarded this compound as a useful drug. In 1936, phenytoin's anticonvulsive properties were identified via a new animal model for convulsive disorders, developed by Putnam and Merritt, who also evaluated its clinical value in a number of patients in the period 1937-1940. For many diseases, mechanism of action of phenytoin remains obscure. The voltage-gated sodium channel was and is generally regarded as the main target to explain phenytoin's activity as an anticonvulsant and an anti-arrhythmic drug. This target, however, does not explain many of the other clinical properties of phenytoin. We will explore a number of original articles on phenytoin published in its 80 years history and give extra attention to the various hypothesis and experiments done to elucidate its mechanisms of action. Phenytoin has been explored in over 100 different disorders; the last two promising indications tested in the clinic are breast cancer and optic neuritis. Most probably, there are multiple targets active for these various disorders, and the insight into which targets are relevant is still very incomplete. It is remarkable that many pharmacological studies tested one dose only, mostly 50 or 100 μM, doses which most probably are higher than the non-plasma bound phenytoin plasma levels obtained during treatment.

The role of liquid chromatography-tandem mass spectrometry (LC-MS/MS) to test blood and urine samples for the toxicological investigation of drug-facilitated crimes.

PubMed

Deveaux, Marc; Chèze, Marjorie; Pépin, Gilbert

2008-04-01

The authors present an overview of the drug-facilitated crime (DFC) phenomenon, especially in France. Recently, there has been an increase in reports of incidents (mainly sexual assaults and robbery) as well as in scientific publications and congress presentations on the topic. From enquiries conducted nationally, a list of drugs reportedly associated with DFC was established and includes benzodiazepines and benzodiazepine-like drugs (zolpidem, zopiclone), minor tranquilizers and neuroleptics, barbiturates, narcotics, hallucinogens, and anaesthetics. Some of these molecules are specific to France in DFC cases. A study using healthy volunteers who had taken benzodiazepines (lorazepam, bromazepam, flunitrazepam, clonazepam), zolpidem and zopiclone, showed that the only way to increase the duration of detection of these drugs is to use liquid chromatography-tandem mass spectrometry (LC-MS/MS) to test blood and urine samples. The very high sensitivity of this method appears to be an essential condition to document the cases, because the drugs tested were still detectable in urine at least 6 days after the ingestion of one therapeutic dose. Limits of detection were always lower than 0.5 ng/mL in urine. The actual list of molecules and metabolites the authors screened for in urine and blood by LC-MS/MS, in every DFC, is given in detail: 25 benzodiazepines and benzodiazepine-like drugs, 11 minor tranquilizers and neuroleptics, 2 barbiturates, 12 narcotics, 4 hallucinogens, and 1 anaesthetic. However, the distinction between continual therapeutic use of a psychotropic drug or illegal narcotic and a single ingestion has to be documented by sequential analysis of hair, again with LC-MS/MS.

[Psychophysiological regin for rehabilition of chronic polydrug users in the Center of the Le Patriarche. 446 cases (author's transl)].

PubMed

Laffont, F; Engelmajer, L; Vourc'h, G; Nahas, G

1980-01-01

From 1974 to 1979, the rehabilitation centers of the association "Le Patriarche" located in the country side of southern France, have received 446 chronic polydrugs users who has consumed at one time or an other cannabis (marihuana, hashish) (87 p. cent), LSD (66 p. cent) and other hallucinogens (35 p. cent), psychodepressants (55 p. cent), psychostimulants (amphetamines, 85 p. cent; cocaïne, 50 p. cent) and opium and its derivatives (brown sugar, 47 p. cent; opiates, 67 p. cent; heroin, 50 p. cent). The dominant addictive drug was heroin and opiates, 52 p. cent, psychodepressants (barbitutiques and benzodiazepines, 33 p. cent, psychostimulants, 15 p. cent. Males were twice as numerous as female. Average age was 21 (range 14-38). Mean duration of drug abuse was 7 years. All these drug abusers display at entrance withdrawal symptoms. These were treated successfully by a drug free, psycho-physiological regimen comprising: 1. An elimination of all psychoactive drugs, including coffee, and alcohol. Tobacco was permitted. 2. Physical therapy (bath, exercise, massage) and forced fluid diuresis. 3. A supportive psychotherapy dispensed by rehabilitated addicts who had undergone successfully a similar regimen. This non-pharmacological method of treating withdrawal symptoms associated with opium, barbiturate and amphetamine addiction, was successful, and was not associated with any major clinical symptoms threatening the vital signs. Mean duration of detoxification was 5 days for opiates, 6 days for amphetamines and 10 days for barbiturates. 78 p. cent of these subjects remained in the centers from 3 months to 2 years, partaking in physical occupational and physiological rehabilitation paograms which allowed then to adopt a drug free life style and prepared them for social reinsertion.

Rates and Correlates of Binge Drinking Among College Students With Disabilities, United States, 2013.

PubMed

West, Steven L; Graham, Carolyn W; Temple, Peter

Our objective was to provide the first comprehensive picture of alcohol use and binge drinking by US college students with disabilities (SWDs), who represent at least 11% (1.6 million) of the US college student population. In fall 2013, we used a stratified random sampling technique to identify and recruit 2440 SWDs from 122 US colleges and universities. A total of 1285 (53%) SWDs from 61 (50%) colleges and universities completed a survey of alcohol and other drug use and the use of substances by student peers. We conducted 4 multiple logistic regression analyses to compare binge-drinking and non-binge-drinking SWDs by potential correlates of such use and a final model that included only significant variables. SWDs aged <21 vs ≥21 (odds ratio [OR] = 0.90; 95% confidence interval [CI], 0.82-0.99) who spent more time vs less time socializing (OR = 1.24; 95% CI, 1.11-1.38), who spent less time vs more time studying (OR = -0.89; 95% CI, -0.80 to -0.99), and who used vs did not use marijuana (OR = 1.44; 95% CI, 1.18-1.75) or amphetamines (OR = 1.82; 95% CI, 1.15-2.89) were significantly more likely to binge drink. SWDs who reported using barbiturates were less likely to binge drink than were those who did not use barbiturates (OR = -0.36; 95% CI, -0.21 to -0.61). In the final model, use of amphetamines (OR = 1.74; 95% CI, 1.15-2.65) or marijuana (OR = 1.60; 95% CI, 1.32-1.94) was the highest predictor of binge drinking. SWDs' reported rates of binge drinking, although high, were not as high as those of nondisabled college students. Nevertheless, prevention efforts should be targeted toward college SWDs.

Enhancement of the release of azelaic acid through the synthetic membranes by inclusion complex formation with hydroxypropyl-beta-cyclodextrin.

PubMed

Manosroi, Jiradej; Apriyani, Maria Goretti; Foe, Kuncoro; Manosroi, Aranya

2005-04-11

The aim of this study was to investigate the release rates of azelaic acid and azelaic acid-hydroxypropyl-beta-cyclodextrin (HPbetaCD) inclusion complex through three types of synthetic membranes, namely cellophane, silicone and elastomer membranes. Solid inclusion complexes of azelaic acid-HPbetaCD at the molar ratio of 1:1 were prepared by coevaporation and freeze-drying methods, subsequently characterized by differential scanning calorimetry, X-ray diffractometry and dissolution studies. Solid inclusion complex obtained by coevaporation method which exhibited the inclusion of azelaic acid in the HPbetaCD cavity and gave the highest dissolution rate of azelaic acid was selected for the release study. Release studies of azelaic acid and this complex through the synthetic membranes were conducted using vertical Franz diffusion cells at 30 degrees C for 6 days. The release rates of azelaic acid through the synthetic membranes were enhanced by the formation of inclusion complex with HPbetaCD at the molar ratio of 1:1, with the increasing fluxes of about 41, 81 and 28 times of the uncomplexed system in cellophane, silicone and elastomer membranes, respectively. The result from this study can be applied for the development of azelaic acid for topical use.

Visual pigments. 11. Spectroscopy and photophysics of retinoic acids and all-trans-methyl retinoate. [Photophysical properties at 77/sup 0/K

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takemura, T.; Chihara, K.; Becker, R.S.

1980-04-09

The photophysics of hydrogen-bonded complexes of retinoic acid and its 9-cis and 13-cis isomers and the photophysics of the dimers of these isomers of retinoic acid were studied. The investigation indicated that complexes of retinoic acid and molecules that form hydrogen bonds with the carbonyl oxygen of retinoic acid (type I complexes) have both higher radiative and nonradiative rate constants than do hydrogen-bonded complexes of retinoic acid and molecules that form hydrogen bonds only with the hydroxyl oxygen of retinoic acid (type II complexes). For all-trans-retinoic acid in 3-methylpentane at 77 K, the type I complexes have radiative rate constantsmore » approximately equal to or greater than 2 x 10/sup 8/ s/sup -1/ and nonradiative rate constants greater than 3 x 10/sup 8/ s/sup -1/. Both the radiative and nonradiative rate constants of the type II complexes of all-trans-retinoic acid at 77 K in 3-methylpentane are less than 1 x 10/sup 8/ s/sup -1/. The dimer of retinoic acid (K(association) = 1 x 10/sup 4/ M/sup -1/ at room temperature for the all-trans isomer) behaves like a type I complex, and its excited-state properties are better understood in terms of hydrogen bonding than in terms of an exciton model. The photophysical properties and triplet-triplet absorption spectrum of methyl retinoate were measured. The study concluded with an examination of some of the implications of this work for the role of hydrogen bonding in the dimers and monomers of retinal and retinol.« less

Design of stereoelectronically promoted super lewis acids and unprecedented chemistry of their complexes.

PubMed

Foroutan-Nejad, Cina; Vicha, Jan; Marek, Radek

2014-09-01

A new family of stereoelectronically promoted aluminum and scandium super Lewis acids is introduced on the basis of state-of-the-art computations. Structures of these molecules are designed to minimize resonance electron donation to central metal atoms in the Lewis acids. Acidity of these species is evaluated on the basis of their fluoride-ion affinities relative to the antimony pentafluoride reference system. It is demonstrated that introduced changes in the stereochemistry of the designed ligands increase acidity considerably relative to Al and Sc complexes with analogous monodentate ligands. The high stability of fluoride complexes of these species makes them ideal candidates to be used as weakly coordinating anions in combination with highly reactive cations instead of conventional Lewis acid-fluoride complexes. Further, the interaction of all designed molecules with methane is investigated. All studied acids form stable pentavalent-carbon complexes with methane. In addition, interactions of the strongest acid of this family with very weak bases, namely, H2, N2, carbon oxides, and noble gases were investigated; it is demonstrated that this compound can form considerably stable complexes with the aforementioned molecules. To the best of our knowledge, carbonyl and nitrogen complexes of this species are the first hypothetical four-coordinated carbonyl and nitrogen complexes of aluminum. The nature of bonding in these systems is studied in detail by various bonding analysis approaches. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Thermal transformation of bioactive caffeic acid on fumed silica seen by UV-Vis spectroscopy, thermogravimetric analysis, temperature programmed desorption mass spectrometry and quantum chemical methods.

PubMed

Kulik, Tetiana V; Lipkovska, Natalia O; Barvinchenko, Valentyna M; Palyanytsya, Borys B; Kazakova, Olga A; Dudik, Olesia O; Menyhárd, Alfréd; László, Krisztina

2016-05-15

Thermochemical studies of hydroxycinnamic acid derivatives and their surface complexes are important for the pharmaceutical industry, medicine and for the development of technologies of heterogeneous biomass pyrolysis. In this study, structural and thermal transformations of caffeic acid complexes on silica surfaces were studied by UV-Vis spectroscopy, thermogravimetric analysis, temperature programmed desorption mass spectrometry (TPD MS) and quantum chemical methods. Two types of caffeic acid surface complexes are found to form through phenolic or carboxyl groups. The kinetic parameters of the chemical reactions of caffeic acid on silica surface are calculated. The mechanisms of thermal transformations of the caffeic chemisorbed surface complexes are proposed. Thermal decomposition of caffeic acid complex chemisorbed through grafted ester group proceeds via three parallel reactions, producing ketene, vinyl and acetylene derivatives of 1,2-dihydroxybenzene. Immobilization of phenolic acids on the silica surface improves greatly their thermal stability. Copyright © 2016 Elsevier Inc. All rights reserved.

21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

Code of Federal Regulations, 2014 CFR

2014-04-01

... (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.315 Nicotinamide-ascorbic acid complex. Nicotinamide-ascorbic acid complex may be safely used in accordance with the following prescribed conditions: (a) The additive is the product of...

Spectra, energy levels, and energy transition of lanthanide complexes with cinnamic acid and its derivatives.

PubMed

Zhou, Kaining; Feng, Zhongshan; Shen, Jun; Wu, Bing; Luo, Xiaobing; Jiang, Sha; Li, Li; Zhou, Xianju

2016-04-05

High resolution spectra and luminescent lifetimes of 6 europium(III)-cinnamic acid complex {[Eu2L6(DMF)(H2O)]·nDMF·H2O}m (L=cinnamic acid I, 4-methyl-cinnamic acid II, 4-chloro-cinnamic acid III, 4-methoxy-cinnamic acid IV, 4-hydroxy-cinnamic acid V, 4-nitro-cinnamic acid VI; DMF=N, N-dimethylformamide, C3H7NO) were recorded from 8 K to room temperature. The energy levels of Eu(3+) in these 6 complexes are obtained from the spectra analysis. It is found that the energy levels of the central Eu(3+) ions are influenced by the nephelauxetic effect, while the triplet state of ligand is lowered by the p-π conjugation effect of the para-substituted functional groups. The best energy matching between the ligand triplet state and the central ion excited state is found in complex I. While the other complexes show poorer matching because the gap of (5)D0 and triplet state contracts. Copyright © 2016 Elsevier B.V. All rights reserved.

Removal of acidic or basic α-amino acids in water by poorly water soluble scandium complexes.

PubMed

Hayashi, Nobuyuki; Jin, Shigeki; Ujihara, Tomomi

2012-11-02

To recognize α-amino acids with highly polar side chains in water, poorly water soluble scandium complexes with both Lewis acidic and basic portions were synthesized as artificial receptors. A suspension of some of these receptor molecules in an α-amino acid solution could remove acidic and basic α-amino acids from the solution. The compound most efficient at preferentially removing basic α-amino acids (arginine, histidine, and lysine) was the receptor with 7,7'-[1,3-phenylenebis(carbonylimino)]bis(2-naphthalenesulfonate) as the ligand. The neutral α-amino acids were barely removed by these receptors. Removal experiments using a mixed amino acid solution generally gave results similar to those obtained using solutions containing a single amino acid. The results demonstrated that the scandium complex receptors were useful for binding acidic and basic α-amino acids.

Crystal and molecular structure of eight organic acid-base adducts from 2-methylquinoline and different acids

NASA Astrophysics Data System (ADS)

Zhang, Jing; Jin, Shouwen; Tao, Lin; Liu, Bin; Wang, Daqi

2014-08-01

Eight supramolecular complexes with 2-methylquinoline and acidic components as 4-aminobenzoic acid, 2-aminobenzoic acid, salicylic acid, 5-chlorosalicylic acid, 3,5-dinitrosalicylic acid, malic acid, sebacic acid, and 1,5-naphthalenedisulfonic acid were synthesized and characterized by X-ray crystallography, IR, mp, and elemental analysis. All of the complexes are organic salts except compound 2. All supramolecular architectures of 1-8 involve extensive classical hydrogen bonds as well as other noncovalent interactions. The results presented herein indicate that the strength and directionality of the classical hydrogen bonds (ionic or neutral) between acidic components and 2-methylquinoline are sufficient to bring about the formation of binary organic acid-base adducts. The role of weak and strong noncovalent interactions in the crystal packing is ascertained. These weak interactions combined, the complexes 1-8 displayed 2D-3D framework structure.

Spectral and thermal study of the ternary complexes of nickel with sulfasalazine and some amino acids

NASA Astrophysics Data System (ADS)

Soliman, Ahmed A.

2006-12-01

The ternary complexes of Ni(II) with sulfasalazine (H 3SS) as a primary ligand and alanine (ala), aspartic acid (asp), histidene (hist), methionine (meth) and serine (ser) amino acids as secondary ligands have been synthesized. Characterization of the complexes was based on elemental analyses, IR, UV-vis, mass spectra, magnetic moment and thermal analysis (TG). The isolated complexes were found to have the general formula [M(HSS)(AA)]4H 2O (AA = ala, asp, hist, meth, or ser amino acid) where nickel is tetra-coordinated. The thermal stability of the complexes was studied and the weight losses for the decomposition of the complexes were calculated and correlated with the mass fragmentation pattern. In most cases, the amino acid moiety is removed along with the Schiff base moiety leaving NiO as a metallic residue. The metallic residue was confirmed by powder XRD measurements.

Deprotonated Dicarboxylic Acid Homodimers: Hydrogen Bonds and Atmospheric Implications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hou, Gao-Lei; Valiev, Marat; Wang, Xue-Bin

Dicarboxylic acids represent an important class of water-soluble organic compounds found in the atmosphere. In this work we are studying properties of dicarboxylic acid homodimer complexes (HO 2(CH 2) nCO 2 -[HO 2(CH 2) nCO 2H], n = 0-12), as potentially important intermediates in aerosol formation processes. Our approach is based on experimental data from negative ion photoelectron spectra of the dimer complexes combined with updated measurements of the corresponding monomer species. These results are analyzed with quantum-mechanical calculations, which provide further information about equilibrium structures, thermochemical parameters associated with the complex formation, and evaporation rates. We find that uponmore » formation of the dimer complexes the electron binding energies increase by 1.3–1.7 eV (30.0–39.2 kcal/mol), indicating increased stability of the dimerized complexes. Calculations indicate that these dimer complexes are characterized by the presence of strong intermolecular hydrogen bonds with high binding energies and are thermodynamically favorable to form with low evaporation rates. Comparison with previously studied HSO 4 -[HO 2(CH 2) 2CO 2H] complex (J. Phys. Chem. Lett. 2013, 4, 779-785) shows that HO 2(CH 2) 2CO 2 -[HO 2(CH 2) 2CO 2H] has very similar thermochemical properties. These results imply that dicarboxylic acids not only can contribute to the heterogeneous complexes formation involving sulfuric acid and dicarboxylic acids, but also can promote the formation of homogenous complexes by involving dicarboxylic acids themselves.« less

40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

Code of Federal Regulations, 2014 CFR

2014-07-01

... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737) is...

40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

Code of Federal Regulations, 2011 CFR

2011-07-01

... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737) is...

40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

Code of Federal Regulations, 2013 CFR

2013-07-01

... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737) is...

40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

Code of Federal Regulations, 2010 CFR

2010-07-01

... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737) is...

40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

Code of Federal Regulations, 2012 CFR

2012-07-01

... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737) is...

Signal enhancement of carboxylic acids by inclusion with β-cyclodextrin in negative high-voltage-assisted laser desorption ionization mass spectrometry.

PubMed

Ren, Xinxin; Liu, Jia; Zhang, Chengsen; Sun, Jiamu; Luo, Hai

2014-01-15

It is difficult to directly analyze carboxylic acids in complex mixtures by ambient high-voltage-assisted laser desorption ionization mass spectrometry (HALDI-MS) in negative ion mode due to the low ionization efficiency of carboxylic acids. A method for the rapid detection of carboxylic acids in negative HALDI-MS has been developed based on their inclusion with β-cyclodextrin (β-CD). The negative HALDI-MS signal-to-noise ratios (S/Ns) of aliphatic, aromatic and hetero atom-containing carboxylic acids can all be significantly improved by forming 1:1 complexes with β-CD. These complexes are mainly formed by specific inclusion interactions which are verified by their collision-induced dissociation behaviors in comparison with that of their corresponding maltoheptaose complexes. A HALDI-MS/MS method has been successfully developed for the detection of α-lipoic acid in complex cosmetics and ibuprofen in a viscous drug suspension. The negative HALDI-MS S/Ns of carboxylic acids can be improved up to 30 times via forming non-covalent complexes with β-CD. The developed method shows the advantages of being rapid and simple, and is promising for rapid detection of active ingredients in complex samples or fast screening of drugs and cosmetics. Copyright © 2013 John Wiley & Sons, Ltd.

Successful use of haemodialysis to treat phenobarbital overdose.

PubMed

Hoyland, Kimberley; Hoy, Michael; Austin, Richard; Wildman, Martyn

2013-11-21

A 50-year-old woman presented with coma caused by a phenobarbital overdose, requiring intubation and admission to critical care. She was an international visitor and had been prescribed the drug for night-sedation. Phenobarbital is a long-acting barbiturate, which in an overdose can cause central nervous system depression, respiratory failure and haemodynamic instability; these patients can remain obtunded for many days. After initial supportive therapy, she was dialysed to help in the elimination of the drug. Haemodialysis resulted in a markedly reduced plasma level of phenobarbital, which decreased the length of intubation and stay in the critical care unit and aided full recovery.

Successful use of haemodialysis to treat phenobarbital overdose

PubMed Central

Hoyland, Kimberley; Hoy, Michael; Austin, Richard; Wildman, Martyn

2013-01-01

A 50-year-old woman presented with coma caused by a phenobarbital overdose, requiring intubation and admission to critical care. She was an international visitor and had been prescribed the drug for night-sedation. Phenobarbital is a long-acting barbiturate, which in an overdose can cause central nervous system depression, respiratory failure and haemodynamic instability; these patients can remain obtunded for many days. After initial supportive therapy, she was dialysed to help in the elimination of the drug. Haemodialysis resulted in a markedly reduced plasma level of phenobarbital, which decreased the length of intubation and stay in the critical care unit and aided full recovery. PMID:24265338

Interactions between clinically used drugs and oral contraceptives.

PubMed Central

Bolt, H M

1994-01-01

Metabolism of contraceptive compounds may be influenced by various drugs. Of clinical importance is induction by barbiturates, by diphenylhydantoin, and especially by rifampicin, of enzymes that are responsible for degradation of estrogens. The major target is the hepatic microsomal estrogen-2-hydroxylase (cytochrome P450 3A4). Another type of interaction of drugs with disposition and effectiveness of estrogens is impairment of their enterohepatic circulation. This may be due to absorption of biliary estrogen conjugates (e.g., by cholestyramine) or to insufficient cleavage of the conjugate by intestinal bacteria, the latter being observed after administration of antibiotics (e.g., ampicillin, neomycin). PMID:7698081

Low-frequency vibrational modes of DL-homocysteic acid and related compounds.

PubMed

Yang, Limin; Zhao, Guozhong; Li, Weihong; Liu, Yufeng; Shi, Xiaoxi; Jia, Xinfeng; Zhao, Kui; Lu, Xiangyang; Xu, Yizhuang; Xie, Datao; Wu, Jinguang; Chen, Jia'er

2009-09-01

In this paper several polycrystalline molecules with sulfonate groups and some of their metal complexes, including DL-homocysteic acid (DLH) and its Sr- and Cu-complexes, pyridine-3-sulphonic acid and its Co- and Ni-complexes, sulfanilic acid and L-cysteic acid were investigated using THz time-domain methods at room temperature. The results of THz absorption spectra show that the molecules have characteristic bands in the region of 0.2-2.7 THz (6-90 cm(-1)). THz technique can be used to distinguish different molecules with sulfonate groups and to determine the bonding of metal ions and the changes of hydrogen bond networks. In the THz region DLH has three bands: 1.61, 1.93 and 2.02 THz; and 0.85, 1.23 and 1.73 THz for Sr-DLH complex, 1.94 THz for Cu-DLH complex, respectively. The absorption bands of pyridine-3-sulphonic acid are located at 0.81, 1.66 and 2.34 THz; the bands at 0.96, 1.70 and 2.38 THz for its Co-complex, 0.76, 1.26 and 1.87 THz for its Ni-complex. Sulphanilic acid has three bands: 0.97, 1.46 and 2.05 THz; and the absorption bands of l-cysteic acid are at 0.82, 1.62, 1.87 and 2.07 THz, respectively. The THz absorption spectra after complexation are different from the ligands, which indicate the bonding of metal ions and the changes of hydrogen bond networks. M-O and other vibrations appear in the FIR region for those metal-ligand complexes. The bands in the THz region were assigned to the rocking, torsion, rotation, wagging and other modes of different groups in the molecules. Preliminary assignments of the bands were carried out using Gaussian program calculation.

β-Lactoglobulin-linoleate complexes: In vitro digestion and the role of protein in fatty acid uptake.

PubMed

Le Maux, Solène; Brodkorb, André; Croguennec, Thomas; Hennessy, Alan A; Bouhallab, Saïd; Giblin, Linda

2013-07-01

The dairy protein β-lactoglobulin (BLG) is known to bind fatty acids such as the salt of the essential longchain fatty acid linoleic acid (cis,cis-9,12-octadecadienoic acid, n-6, 18:2). The aim of the current study was to investigate how bovine BLG-linoleate complexes, of various stoichiometry, affect the enzymatic digestion of BLG and the intracellular transport of linoleate into enterocyte-like monolayers. Duodenal and gastric digestions of the complexes indicated that BLG was hydrolyzed more rapidly when complexed with linoleate. Digested as well as undigested BLG-linoleate complexes reduced intracellular linoleate transport as compared with free linoleate. To investigate whether enteroendocrine cells perceive linoleate differently when part of a complex, the ability of linoleate to increase production or secretion of the enteroendocrine satiety hormone, cholecystokinin, was measured. Cholecystokinin mRNA levels were different when linoleate was presented to the cells alone or as part of a protein complex. In conclusion, understanding interactions between linoleate and BLG could help to formulate foods with targeted fatty acid bioaccessibility and, therefore, aid in the development of food matrices with optimal bioactive efficacy. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The historical significance of anaesthesia events at Pearl Harbor.

PubMed

Crowhurst, Ja

2014-07-01

Up to the end of World War II, less than 10% of the general anaesthetics administered was with intravenous barbiturates. The remaining 90% of anaesthetics given in the USA were with diethyl ether. In the United Kingdom and elsewhere, chloroform was also popular. Diethyl ether administration was a relatively safe and simple procedure, often delegated to nurses or junior doctors with little or no specific training in anaesthesia. During the Japanese attack on the US bases at Pearl Harbor, with reduced stocks of diethyl ether available, intravenous Sodium Pentothal(®), a most 'sophisticated and complex' drug, was used with devastating effects in many of those hypovolaemic, anaemic and septic patients. The hazards of spinal anaesthesia too were realised very quickly. These effects were compounded by the dearth of trained anaesthetists. This paper presents the significance of the anaesthesia tragedies at Pearl Harbor, and the discovery in the next few years of many other superior drugs that caused medical and other health professionals to realise that anaesthesia needed to be a specialist medical discipline in its own right. Specialist recognition, aided by the foundation of the National Health Service in the UK, the establishment of Faculties of Anaesthesia and appropriate training in pharmacology, physiology and other sciences soon followed. Modern anaesthesiology, as we understand it today, was born and a century or more of ether anaesthesia finally ceased.

Development of a novel ultrasensitive enzyme immunoassay for human glutamic acid decarboxylase 65 antibody.

PubMed

Numata, Satoshi; Katakami, Hideki; Inoue, Shinobu; Sawada, Hirotake; Hashida, Seiichi

2016-07-01

We developed a novel, ultrasensitive enzyme immunoassay (immune complex transfer enzyme immunoassay) for determination of glutamic acid decarboxylase autoantibody concentrations in serum samples from patients with type 2 diabetes. We developed an immune complex transfer enzyme immunoassay for glutamic acid decarboxylase autoantibody and measured glutamic acid decarboxylase autoantibody from 22 patients with type 1 diabetes, 29 patients with type 2 diabetes, and 32 healthy controls. A conventional ELISA kit identified 10 patients with type 1 diabetes and one patient with type 2 diabetes as glutamic acid decarboxylase autoantibody positive, whereas 15 patients with type 1 diabetes and six patients with type 2 diabetes were identified as glutamic acid decarboxylase autoantibody positive using immune complex transfer enzyme immunoassay. Immune complex transfer enzyme immunoassay is a highly sensitive and specific assay for glutamic acid decarboxylase autoantibody and might be clinically useful for diabetic onset prediction and early diagnosis. © The Author(s) 2016.

A new approach to study cadmium complexes with oxalic acid in soil solution.

PubMed

Dytrtová, Jana Jaklová; Jakl, Michal; Sestáková, Ivana; Zins, Emilie-Laure; Schröder, Detlef; Navrátil, Tomáš

2011-05-05

This study presents a new analytical approach for the determination of heavy metals complexed to low-molecular-weight-organic acids in soil solutions, which combines the sensitivity of differential pulse anodic stripping voltammetry (DPASV) with the molecular insight gained by electrospray ionization mass spectrometry (ESI-MS). The combination of these analytical methods allows the investigation of such complexes in complex matrixes. On the voltammograms of the soil solutions, in addition to the expected complexes of oxalic acid with cadmium and lead, respectively, also peaks belonging to mixed complexes of cadmium, lead, and oxalic acid (OAH(2)) were observed. In order to verify the possible formation of complexes with OAH(2), aqueous solutions of OAH(2) with traces of Cd(II) were investigated as model systems. Signals corresponding to several distinct molecular complexes between cadmium and oxalic acid were detected in the model solutions using negative-ion ESI-MS, which follow the general formula [Cd(n)(X,Y)((2n+1))](-), where n is the number of cadmium atoms, X=Cl(-), and Y=OAH(-). Some of these complexes were also identified in the ESI mass spectra taken from the soil solutions. Copyright © 2011 Elsevier B.V. All rights reserved.

Amylose-dicarboxylic acid inclusion complexes: Characterization and comparison to monocarboxylic acid complexes

USDA-ARS?s Scientific Manuscript database

One of the main components in starch, amylose is an essentially linear polymer composed of glucose connected through alpha-1,4-bonds. Amylose is well known to form helical inclusion complexes with various types of ligands such as iodine, medium and long chain fatty acids, alcohols, lactones, and fl...

Topical Application of Tranexamic Acid to Reduce Blood Loss During Complex Combat Related Spine Trauma Surgery

DTIC Science & Technology

2015-10-01

AWARD NUMBER: W81XWH-14-2-0177 TITLE: Topical Application of Tranexamic Acid to Reduce Blood Loss During Complex Combat-Related Spine Trauma...COVERED (From - To) 30 Sep 2014 - 29 Sep 2015 4. TITLE AND SUBTITLE Topical Application of Tranexamic Acid to Reduce Blood Loss During Complex...application will be submitted shortly and successfully. 15. SUBJECT TERMS Spine; Tranexamic Acid ; Perioperative blood loss; Trauma; Antifibrinolytic

Molecular complexes of alprazolam with carboxylic acids, boric acid, boronic acids, and phenols. Evaluation of supramolecular heterosynthons mediated by a triazole ring.

PubMed

Varughese, Sunil; Azim, Yasser; Desiraju, Gautam R

2010-09-01

A series of molecular complexes, both co-crystals and salts, of a triazole drug-alprazolam-with carboxylic acids, boric acid, boronic acids, and phenols have been analyzed with respect to heterosynthons present in the crystal structures. In all cases, the triazole ring behaves as an efficient hydrogen bond acceptor with the acidic coformers. The hydrogen bond patterns exhibited with aromatic carboxylic acids were found to depend on the nature and position of the substituents. Being a strong acid, 2,6-dihydroxybenzoic acid forms a salt with alprazolam. With aliphatic dicarboxylic acids alprazolam forms hydrates and the water molecules play a central role in synthon formation and crystal packing. The triazole ring makes two distinct heterosynthons in the molecular complex with boric acid. Boronic acids and phenols form consistent hydrogen bond patterns, and these are seemingly independent of the substitutional effects. Boronic acids form noncentrosymmetric cyclic synthons, while phenols form O--H...N hydrogen bonds with the triazole ring.

In situ synthesis of twelve dialkyltartrate-boric acid complexes and two polyols-boric acid complexes and their applications as chiral ion-pair selectors in nonaqueous capillary electrophoresis.

PubMed

Wang, Li-Juan; Yang, Juan; Yang, Geng-Liang; Chen, Xing-Guo

2012-07-27

In this paper, twelve dialkyltartrate-boric acid complexes and two polyols-boric acid complexes were in situ synthesized by the reaction of different dialkyltartrates or polyols with boric acid in methanol containing triethylamine. All of the twelve dialkyltartrate-boric acid complexes were found to have relatively good chiral separation performance in nonaqueous capillary electrophoresis (NACE). Their chiral recognition effects in terms of both enantioselectivity (α) and resolution (R(s)) were similar when the number of carbon atoms was below six in the alkyl group of alcohol moiety. The dialkyltartrates containing alkyl groups of different structures but the same number of carbon atoms, i.e. one of straight chain and one of branched chain, also provided similar chiral recognition effects. Furthermore, it was demonstrated for the first time that two methanol insoluble polyols, D-mannitol and D-sorbitol, could react with boric acid to prepare chiral ion-pair selectors using methanol as the solvent medium. Copyright © 2012 Elsevier B.V. All rights reserved.

Chemical synthesis of water-soluble, chiral conducting-polymer complexes

DOEpatents

Wang, Hsing-Lin; McCarthy, Patrick A.; Yang, Sze Cheng

2003-01-01

The template-guided synthesis of water-soluble, chiral conducting polymer complexes is described. Synthesis of water-soluble polyaniline complexes is achieved by carefully controlling the experimental parameters such as; acid concentration, ionic strength, monomer/template ratio, total reagent concentration, and order of reagent addition. Chiral (helical) polyaniline complexes can be synthesized by addition of a chiral inducing agent (chiral acid) prior to polymerization, and the polyaniline helix can be controlled by the addition of the (+) or (-) form of the chiral acid. Moreover the quantity of chiral acid and the salt content has a significant impact on the degree of chirality in the final polymer complexes. The polyaniline and the template have been found to be mixed at the molecular level which results in chiral complexes that are robust through repeated doping and dedoping cycles.

Syntheses, structural, computational, and thermal analysis of acid-base complexes of picric acid with N-heterocyclic bases.

PubMed

Goel, Nidhi; Singh, Udai P

2013-10-10

Four new acid-base complexes using picric acid [(OH)(NO2)3C6H2] (PA) and N-heterocyclic bases (1,10-phenanthroline (phen)/2,2';6',2"-terpyridine (terpy)/hexamethylenetetramine (hmta)/2,4,6-tri(2-pyridyl)-1,3,5-triazine (tptz)) were prepared and characterized by elemental analysis, IR, NMR and X-ray crystallography. Crystal structures provide detailed information of the noncovalent interactions present in different complexes. The optimized structures of the complexes were calculated in terms of the density functional theory. The thermolysis of these complexes was investigated by TG-DSC and ignition delay measurements. The model-free isoconversional and model-fitting kinetic approaches have been applied to isothermal TG data for kinetics investigation of thermal decomposition of these complexes.

Synthesis and effect of a new Terbium gibberellic complex on the histopathological alteration induced by Gibberellic acid on liver and kidney of mice Mus musculus.

PubMed

Seleem, Amin A; Hussein, Belal H M

2018-03-25

The objective of this study was to synthesize Gibberellic lanthanide complex and evaluate its biological activity to reduce the Gibberellic acid toxicity on liver and kidney. The new bis(Gibberellic)-nitro-terbium(III) complex was characterized by different analytical methods: elemental analyses, UV-Vis, molar ratio, fluorescence, FT-IR, and TGA-DTA measurements. Thirty newborns were classified into three groups control, Gibberellic acid, and Terbium gibberellic acid complex. Livers and kidneys of studied groups proceed for general histology and immunohistochemical staining of Cyr61, cytochrome C, and TNFR2. From the absorption titration measurements, the binding constants of DNA with Tb(III)-(GA) 2 complex and free ligand were found to be 3.9 × 10 4 and 2.1 × 10 3  m -1 , respectively, with the stoichiometry of 1:1. Hypochromism was observed from the absorption titration experiment which indicates the intercalation of Tb(III)-(GA) 2 complex between the base pairs of DNA. Gibberellic acid-treated group showed alteration in the histological picture of livers and kidneys that accompanied with the reduction in the expression of Cyr61, cyt C, and TNFR2. The amelioration was observed in Gibberellic acid complex with Terbium group. The study concluded that Terbium gibberellic complex is less dangerous effects than Gibberellic acid alone. © 2018 John Wiley & Sons A/S.

Asymmetric synthesis of α-amino acids via homologation of Ni(II) complexes of glycine Schiff bases; Part 1: alkyl halide alkylations.

PubMed

Sorochinsky, Alexander E; Aceña, José Luis; Moriwaki, Hiroki; Sato, Tatsunori; Soloshonok, Vadim A

2013-10-01

Alkylations of chiral or achiral Ni(II) complexes of glycine Schiff bases constitute a landmark in the development of practical methodology for asymmetric synthesis of α-amino acids. Straightforward, easy preparation as well as high reactivity of these Ni(II) complexes render them ready available and inexpensive glycine equivalents for preparing a wide variety of α-amino acids, in particular on a relatively large scale. In the case of Ni(II) complexes containing benzylproline moiety as a chiral auxiliary, their alkylation proceeds with high thermodynamically controlled diastereoselectivity. Similar type of Ni(II) complexes derived from alanine can also be used for alkylation providing convenient access to quaternary, α,α-disubstituted α-amino acids. Achiral type of Ni(II) complexes can be prepared from picolinic acid or via recently developed modular approach using simple secondary or primary amines. These Ni(II) complexes can be easily mono/bis-alkylated under homogeneous or phase-transfer catalysis conditions. Origin of diastereo-/enantioselectivity in the alkylations reactions, aspects of practicality, generality and limitations of this methodology is critically discussed.

Separation of compounds with multiple -OH groups from dilute aqueous solutions via complexation with organoboronate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chow, Tina Kuo Fung

1992-05-01

The complexing extractant agent investigated in this work is 3-nitrophenylboronic acid (NPBA) in its anionic form (NPB). NPBA and Aliquat 336 (quaternary amine) is dissolved in 2-ethyl-l-hexanol, and the extractant is contacted with aq. NaOH. Solutes investigated were 1,2-propanediol, glycerol, fructose, sorbitol and lactic acid. Batch extraction experiments were performed at 25°C. Partition coefficients, distribution ratios and loadings are reported for varying concentrations of solute and NPB. All solutes complexed with NPB -, with all complexes containing only one NPB - per complex. The 1:1 complexation constants for the solutes glycerol, fructose and sorbitol follow trends similar to complexation withmore » B(OH) 4 - (aq.), i.e. the complexation constants increase with increasing number of -OH groups available for complexation. Assumption of 1:1 complex is not valid for 1, 2-propanediol, which showed overloading (more than one mole of solute complexed to one mole NPB -) at higher concentrations. The -OH group on the NPB - which is left uncomplexed after one solute molecule had bound to the other two -OH groups may be responsible for the overloading. Overloading is also observed in extraction of tactic acid, but through a different mechanism. It was found that TOMA + can extract lactic acid to an extent comparable to the uptake of lactic acid by NPB -. The complexation is probably through formation of an acid-base ion pair. Losses of NPBA into the aqueous phase could lead to problems, poor economics in industrial separation processes. One way of overcoming this problem would be to incorporate the NPBA onto a solid support.« less

Separation of compounds with multiple -OH groups from dilute aqueous solutions via complexation with organoboronate. [1,2-propanediol

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chow, Tina Kuo Fung.

1992-05-01

The complexing extractant agent investigated in this work is 3-nitrophenylboronic acid (NPBA) in its anionic form (NPB). NPBA and Aliquat 336 (quaternary amine) is dissolved in 2-ethyl-l-hexanol, and the extractant is contacted with aq. NaOH. Solutes investigated were 1,2-propanediol, glycerol, fructose, sorbitol and lactic acid. Batch extraction experiments were performed at 25{degree}C. Partition coefficients, distribution ratios and loadings are reported for varying concentrations of solute and NPB. All solutes complexed with NPB{sup {minus}}, with all complexes containing only one NPB{sup {minus}} per complex. The 1:1 complexation constants for the solutes glycerol, fructose and sorbitol follow trends similar to complexation withmore » B(OH){sub 4}{sup {minus}} (aq.), i.e. the complexation constants increase with increasing number of {minus}OH groups available for complexation. Assumption of 1:1 complex is not valid for 1, 2-propanediol, which showed overloading (more than one mole of solute complexed to one mole NPB{sup {minus}}) at higher concentrations. The {minus}OH group on the NPB{sup {minus}} which is left uncomplexed after one solute molecule had bound to the other two {minus}OH groups may be responsible for the overloading. Overloading is also observed in extraction of tactic acid, but through a different mechanism. It was found that TOMA{sup +} can extract lactic acid to an extent comparable to the uptake of lactic acid by NPB{sup {minus}}. The complexation is probably through formation of an acid-base ion pair. Losses of NPBA into the aqueous phase could lead to problems, poor economics in industrial separation processes. One way of overcoming this problem would be to incorporate the NPBA onto a solid support.« less

Microencapsulation of methylglyoxal and two derivatives

NASA Technical Reports Server (NTRS)

Nozawa, Y.; Fox, S. W.

1981-01-01

Microcapsules of methylglyoxal, methylglyoxal bis(guanylhydrazone), and methylglyoxal-ascorbic acid condensation complex were prepared and release curves were determined. The effect of various concentrations of hydrochloric acid on the decomposition of the ascorbic acid complex was investigated.

Design, synthesis and evaluation of a new Mn - Contrast agent for MR imaging of myocardium based on the DTPA-phenylpentadecanoic acid complex

NASA Astrophysics Data System (ADS)

Belyanin, Maxim L.; Stepanova, Elena V.; Valiev, Rashid R.; Filimonov, Victor D.; Usov, Vladimir Y.; Borodin, Oleg Y.; Ågren, Hans

2016-11-01

In the present paper we describe the first synthesis and evaluation of a novel Mn (II) complex (DTPA-PPDA Mn (II)) which contains a C-15 fatty acid moiety that has high affinity to the heart muscle. The complexation energy of DTPA-PPDA Mn (II) evaluated by quantum chemistry methodology indicates that it essentially exceeds the corresponding value for the known DTPA Mn (II) complex. Molecular docking revealed that the affinity of the designed complex to the heart-type transport protein H-FABP well exceeds that of lauric acid. Phantom experiments in low-field MRI the designed contrast agent provides MR imaging comparable to gadopentetic acid.

Physiologically based pharmacokinetic modeling of a homologous series of barbiturates in the rat: a sensitivity analysis.

PubMed

Nestorov, I A; Aarons, L J; Rowland, M

1997-08-01

Sensitivity analysis studies the effects of the inherent variability and uncertainty in model parameters on the model outputs and may be a useful tool at all stages of the pharmacokinetic modeling process. The present study examined the sensitivity of a whole-body physiologically based pharmacokinetic (PBPK) model for the distribution kinetics of nine 5-n-alkyl-5-ethyl barbituric acids in arterial blood and 14 tissues (lung, liver, kidney, stomach, pancreas, spleen, gut, muscle, adipose, skin, bone, heart, brain, testes) after i.v. bolus administration to rats. The aims were to obtain new insights into the model used, to rank the model parameters involved according to their impact on the model outputs and to study the changes in the sensitivity induced by the increase in the lipophilicity of the homologues on ascending the series. Two approaches for sensitivity analysis have been implemented. The first, based on the Matrix Perturbation Theory, uses a sensitivity index defined as the normalized sensitivity of the 2-norm of the model compartmental matrix to perturbations in its entries. The second approach uses the traditional definition of the normalized sensitivity function as the relative change in a model state (a tissue concentration) corresponding to a relative change in a model parameter. Autosensitivity has been defined as sensitivity of a state to any of its parameters; cross-sensitivity as the sensitivity of a state to any other states' parameters. Using the two approaches, the sensitivity of representative tissue concentrations (lung, liver, kidney, stomach, gut, adipose, heart, and brain) to the following model parameters: tissue-to-unbound plasma partition coefficients, tissue blood flows, unbound renal and intrinsic hepatic clearance, permeability surface area product of the brain, have been analyzed. Both the tissues and the parameters were ranked according to their sensitivity and impact. The following general conclusions were drawn: (i) the overall sensitivity of the system to all parameters involved is small due to the weak connectivity of the system structure; (ii) the time course of both the auto- and cross-sensitivity functions for all tissues depends on the dynamics of the tissues themselves, e.g., the higher the perfusion of a tissue, the higher are both its cross-sensitivity to other tissues' parameters and the cross-sensitivities of other tissues to its parameters; and (iii) with a few exceptions, there is not a marked influence of the lipophilicity of the homologues on either the pattern or the values of the sensitivity functions. The estimates of the sensitivity and the subsequent tissue and parameter rankings may be extended to other drugs, sharing the same common structure of the whole body PBPK model, and having similar model parameters. Results show also that the computationally simple Matrix Perturbation Analysis should be used only when an initial idea about the sensitivity of a system is required. If comprehensive information regarding the sensitivity is needed, the numerically expensive Direct Sensitivity Analysis should be used.

Complexation of Nickel Ions by Boric Acid or (Poly)borates.

PubMed

Graff, Anais; Barrez, Etienne; Baranek, Philippe; Bachet, Martin; Bénézeth, Pascale

2017-01-01

An experiment based on electrochemical reactions and pH monitoring was performed in which nickel ions were gradually formed by oxidation of a nickel metal electrode in a solution of boric acid. Based on the experimental results and aqueous speciation modeling, the evolution of pH showed the existence of significant nickel-boron complexation. A triborate nickel complex was postulated at high boric acid concentrations when polyborates are present, and the equilibrium constants were determined at 25, 50 and 70 °C. The calculated enthalpy and entropy at 25 °C for the formation of the complex from boric acid and Ni 2+ ions are respectively equal to (65.6 ± 3.1) kJ·mol -1 and (0.5 ± 11.1) J·K -1 ·mol -1 . The results of this study suggest that complexation of nickel ions by borates can significantly enhance the solubility of nickel metal and nickel oxide depending on the concentration of boric acid and pH. First principles calculations were investigated and tend to show that the complex is thermodynamically stable and the nickel cation in solution should interact more strongly with the [Formula: see text] than with boric acid.

Synthesis and spectroscopic characterization of gallic acid and some of its azo complexes

NASA Astrophysics Data System (ADS)

Masoud, Mamdouh S.; Hagagg, Sawsan S.; Ali, Alaa E.; Nasr, Nessma M.

2012-04-01

A series of gallic acid and azo gallic acid complexes were prepared and characterized by elemental analysis, IR, electronic spectra and magnetic susceptibility. The complexes were of different geometries: Octahedral, Tetrahedral and Square Planar. ESR was studied for copper complexes. All of the prepared complexes were of isotropic nature. The thermal analyses of the complexes were studied by DTA and DSC techniques. The thermodynamic parameters and the thermal transitions, such as glass transitions, crystallization and melting temperatures for some ligands and their complexes were evaluated and discussed. The entropy change values, ΔS#, showed that the transition states are more ordered than the reacting complexes. The biological activities of some ligands and their complexes are tested against Gram positive and Gram negative bacteria. The results showed that some complexes have a well considerable activity against different organisms.

Preparation, characterisation and study of in vitro biologically active azamacrocyclic Cu(II) dicarboxylate complexes

NASA Astrophysics Data System (ADS)

Antonijević-Nikolić, Mirjana; Antić-Stanković, Jelena; Tanasković, Sladjana B.; Korabik, Maria J.; Gojgić-Cvijović, Gordana; Vučković, Gordana

2013-12-01

New cationic Cu(II) complexes with N, N‧, N″, N″‧-tetrakis(2-pyridylmethyl)-1,4,8,11-tetraazacyclotetradecane (tpmc) and aliphatic dicarboxylic acids: pentanedioic (glutaric acid = glutH2), hexanedioic acid (adipic acid = adipH2) and decanedioic acid (sebacic acid = sebH2) of general formula [Cu4(L)(tpmc)2](ClO4)6·xH2O, L = glut, x = 2; L = adip, x = 7; L = seb, x = 6 were isolated. Their composition and charges are proposed based on elemental analyses and molar conductivity measurements. By the comparison of their UV-Vis, reflectance, FTIR and EPR spectral data, CV and SQUID magnetic measurements, with those for the complex with butanedioic acid (succinic acid = succH2) of known molecular structure and analysis of LC/MS spectra, geometry with two [Cu2tpmc]4+ units bridged by dicarboxylate dianion engaging all oxygens is proposed. Within units, Cu(II) ions are also bridged with N portion of cyclam ring. All four complexes were screened to in vitro antimicrobial and cytotoxic activity along with free primary and secondary ligands, Cu(II) salt and solvent controls. Detected antibacterial and cytotoxic activity for the complexes was enhanced in most cases than the corresponding controls.

Antibacterial, antibiofilm and antioxidant screening of copper(II)-complexes with some S-alkyl derivatives of thiosalicylic acid. Crystal structure of the binuclear copper(II)-complex with S-propyl derivative of thiosalicylic acid

NASA Astrophysics Data System (ADS)

Bukonjić, Andriana M.; Tomović, Dušan Lj.; Nikolić, Miloš V.; Mijajlović, Marina Ž.; Jevtić, Verica V.; Ratković, Zoran R.; Novaković, Slađana B.; Bogdanović, Goran A.; Radojević, Ivana D.; Maksimović, Jovana Z.; Vasić, Sava M.; Čomić, Ljiljana R.; Trifunović, Srećko R.; Radić, Gordana P.

2017-01-01

The spectroscopically predicted structure of the obtained copper(II)-complex with S-propyl derivative of thiosalicylic acid was confirmed by X-ray structural study. The binuclear copper(II)-complex with S-propyl derivative of thiosalicylic acid crystallized in two polymorphic forms with main structural difference in the orientation of phenyl rings relative to corresponding carboxylate groups. The antibacterial activity was tested determining the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) by using microdilution method. The influence on bacterial biofilm formation was determined by tissue culture plate method. In general, the copper(II)-complexes manifested a selective and moderate activity. The most sensitive bacteria to the effects of Cu(II)-complexes was a clinical isolate of Pseudomonas aeruginosa. For this bacteria MIC and biofilm inhibitory concentration (BIC) values for all tested complexes were in the range or better than the positive control, doxycycline. Also, for the established biofilm of clinical isolate Staphylococcus aureus, BIC values for the copper(II)-complex with S-ethyl derivative of thiosalicylic acid,[Cu2(S-et-thiosal)4(H2O)2] (C3) and copper(II)-complex with S-butyl derivative of thiosalicylic acid, [Cu2(S-bu-thiosal)4(H2O)2] (C5) were in range or better than the positive control. All the complexes acted better against Gram-positive bacteria (Staphylococcus aureus and Staphylococcus aureus ATCC 25923) than Gram-negative bacteria (Proteus mirabilis ATCC 12453, Pseudomonas aeruginosa, and P. aeruginosa ATCC 27855). The complexes showed weak antioxidative properties tested by two methods (1,1-diphenyl-2-picrylhydrazyl (DPPH) and reducing power assay).

Hydrogen-bonded complexes between dimethyl sulfoxide and monoprotic acids: molecular properties and IR spectroscopy.

PubMed

Belarmino, Márcia K D L; Cruz, Vanessa F; Lima, Nathália B D

2014-11-01

MP2/6-31++G(d,p) and DFT B3LYP/6-31++G(d,p) calculations were performed of the structure, binding energies, and vibrational modes of complexes between dimethyl sulfoxide (DMSO) as a proton acceptor and monoprotic linear acids HX (X = F, Cl, CN) as well as monoprotic carboxylic acids HOOCR (R = -H, -CH3, -C6H5) in 1:1 and 1:2 stoichiometric ratios. The results show that two different structures are possible in the 1:2 ratio: in the first, the DMSO molecule interacts with both acid molecules (leading to a "Y" structure); in the second, the DMSO interacts with only one monoprotic acid. The second structure shows a lower stability per hydrogen bond. The spontaneities of the reactions to form the 1:1 and 1:2 complexes are greatly influenced by the X group of the linear acid. With the exception of HCN, all the reactions are spontaneous. In the 1:2 complexes with Y structure, we observed that the hydrogen atoms of the linear acid are coupled in symmetric and asymmetric modes, while this type of coupling is absent from the other 1:2 complexes.

Antidiabetic effect of the α-lipoic acid γ-cyclodextrin complex.

PubMed

Naito, Yuki; Ikuta, Naoko; Nakata, Daisuke; Terao, Keiji; Matsumoto, Kinuyo; Kajiwara, Naemi; Okano, Ayaka; Yasui, Hiroyuki; Yoshikawa, Yutaka

2014-09-01

In recent years, the number of patients suffering from diabetes mellitus has been increasing worldwide. In particular, type 2 diabetes mellitus, a lifestyle-related disease, is recognized as a serious disease with various complications. Many types of pharmaceutics or specific health foods have been used for the management of diabetes mellitus. At the same time, the relationship between diabetes mellitus and α-lipoic acid has been recognized for many years. In this study, we found that the α-lipoic acid γ-cyclodextrin complex exhibited an HbA1c lowering effect for treating type 2 diabetes mellitus in animal models. Moreover, in this study, we investigated the activation of phosphorylation of AMP-activated protein kinase, which plays a role in cellular energy homeostasis, in the liver of KKA(y) mice by using α-lipoic acid and the α-lipoic acid γ-cyclodextrin complex. Our results show that the α-lipoic acid γ-cyclodextrin complex strongly induced the phosphorylation of AMP-activated protein kinase. Thus, we concluded that intake of the α-lipoic acid γ-cyclodextrin complex exerted an antidiabetic effect by suppressing the elevation of postprandial hyperglycemia as well as doing exercise.

Interaction between Al3+ and acrylic acid and polyacrylic acid in acidic aqueous solution: a model experiment for the behavior of Al3+ in acidified soil solution.

PubMed

Etou, Mayumi; Masaki, Yuka; Tsuji, Yutaka; Saito, Tomoyuki; Bai, Shuqin; Nishida, Ikuko; Okaue, Yoshihiro; Yokoyama, Takushi

2011-01-01

From the viewpoint of the phytotoxicity and mobility of Al(3+) released from soil minerals due to soil acidification, the interaction between Al(3+) and acrylic acid (AA) and polyacrylic acid (PAA) as a model compound of fulvic acid was investigated. The interaction was examined at pH 3 so as to avoid the hydrolysis of Al(3+). The interaction between Al(3+) and AA was weak. However, the interaction between Al(3+) and PAA was strong and depended on the initial (COOH in PAA)/Al molar ratio (R(P)) of the solution. For the range of 1/R(P), the interaction between Al(3+) and PAA can be divided into three categories: (1) 1:1 Al-PAA-complex (an Al(3+) combines to a carboxyl group), (2) intermolecular Al-PAA-complex (an Al(3+) combines to more than 2 carboxyl groups of other Al-PAA-complexes) in addition to the 1:1 Al-PAA-complex and (3) precipitation of intermolecular complexes. In conclusion, R(P) is an important factor affecting the behavior of Al(3+) in acidic soil solution.

Zinc complexes as fluorescent chemosensors for nucleic acids: new perspectives for a "boring" element.

PubMed

Terenzi, Alessio; Lauria, Antonino; Almerico, Anna Maria; Barone, Giampaolo

2015-02-28

Zinc(II) complexes are effective and selective nucleic acid-binders and strongly fluorescent molecules in the low energy range, from the visible to the near infrared. These two properties have often been exploited to quantitatively detect nucleic acids in biological samples, in both in vitro and in vivo models. In particular, the fluorescent emission of several zinc(II) complexes is drastically enhanced or quenched by the binding to nucleic acids and/or upon visible light exposure, in a different fashion in bulk solution and when bound to DNA. The twofold objective of this perspective is (1) to review recent utilisations of zinc(II) complexes as selective fluorescent probes for nucleic acids and (2) to highlight their novel potential applications as diagnostic tools based on their photophysical properties.

Acidity enhancement of unsaturated bases of group 15 by association with borane and beryllium dihydride. Unexpected boron and beryllium Brønsted acids.

PubMed

Martín-Sómer, Ana; Mó, Otilia; Yáñez, Manuel; Guillemin, Jean-Claude

2015-01-21

The intrinsic acidity of CH2[double bond, length as m-dash]CHXH2, HC[triple bond, length as m-dash]CXH2 (X = N, P, As, Sb) derivatives and of their complexes with BeH2 and BH3 has been investigated by means of high-level density functional theory and molecular orbital ab initio calculations, using as a reference the ethyl saturated analogues. The acidity of the free systems steadily increases down the group for the three series of derivatives, ethyl, vinyl and ethynyl. The association with both beryllium dihydride and borane leads to a very significant acidity enhancement, being larger for BeH2 than for BH3 complexes. This acidity enhancement, for the unsaturated compounds, is accompanied by a change in the acidity trends down the group, which do not steadily decrease but present a minimum value for both the vinyl- and the ethynyl-phosphine. When the molecule acting as the Lewis acid is beryllium dihydride, the π-type complexes in which the BeH2 molecules interact with the double or triple bond are found, in some cases, to be more stable, in terms of free energies, than the conventional complexes in which the attachment takes place at the heteroatom, X. The most important finding, however, is that P, As, and Sb ethynyl complexes with BeH2 do not behave as P, As, or Sb Brønsted acids, but unexpectedly as Be acids.

Synthesis of Amino Acid Precursors with Organic Solids in Planetesimals with Liquid Water

NASA Technical Reports Server (NTRS)

Kebukawa, Y; Misawa, S.; Matsukuma, J.; Chan, Q. H. S.; Kobayashi, J.; Tachibana, S.; Zolensky, M. E.

2017-01-01

Amino acids are important ingredients of life that would have been delivered to Earth by extraterrestrial sources, e.g., comets and meteorites. Amino acids are found in aqueously altered carbonaceous chondrites in good part in the form of precursors that release amino acids after acid hydrolysis. Meanwhile, most of the organic carbon (greater than 70 weight %) in carbonaceous chondrites exists in the form of solvent insoluble organic matter (IOM) with complex macromolecular structures. Complex macromolecular organic matter can be produced by either photolysis of interstellar ices or aqueous chemistry in planetesimals. We focused on the synthesis of amino acids during aqueous alteration, and demonstrated one-pot synthesis of a complex suite of amino acids simultaneously with IOM via hydrothermal experiments simulating the aqueous processing

Enhanced splicing correction effect by an oligo-aspartic acid-PNA conjugate and cationic carrier complexes.

PubMed

Bae, Yun Mi; Kim, Myung Hee; Yu, Gwang Sig; Um, Bong Ho; Park, Hee Kyung; Lee, Hyun-il; Lee, Kang Taek; Suh, Yung Doug; Choi, Joon Sig

2014-02-10

Peptide nucleic acids (PNAs) are synthetic structural analogues of DNA and RNA. They recognize specific cellular nucleic acid sequences and form stable complexes with complementary DNA or RNA. Here, we designed an oligo-aspartic acid-PNA conjugate and showed its enhanced delivery into cells with high gene correction efficiency using conventional cationic carriers, such as polyethylenimine (PEI) and Lipofectamine 2000. The negatively charged oligo-aspartic acid-PNA (Asp(n)-PNA) formed complexes with PEI and Lipofectamine, and the resulting Asp(n)-PNA/PEI and Asp(n)-PNA/Lipofectamine complexes were introduced into cells. We observed significantly enhanced cellular uptake of Asp(n)-PNA by cationic carriers and detected an active splicing correction effect even at nanomolar concentrations. We found that the splicing correction efficiency of the complex depended on the kind of the cationic carriers and on the number of repeating aspartic acid units. By enhancing the cellular uptake efficiency of PNAs, these results may provide a novel platform technology of PNAs as bioactive substances for their biological and therapeutic applications. Copyright © 2013 Elsevier B.V. All rights reserved.

alpha-Lactalbumin species variation, HAMLET formation, and tumor cell death.

PubMed

Pettersson, Jenny; Mossberg, Ann-Kristin; Svanborg, Catharina

2006-06-23

HAMLET (human alpha-lactalbumin made lethal to tumor cells) is a tumoricidal complex of apo alpha-lactalbumin and oleic acid, formed in casein after low pH treatment of human milk. This study examined if HAMLET-like complexes are present in casein from different species and if isolated alpha-lactalbumin from those species can form such complexes with oleic acid. Casein from human, bovine, equine, and porcine milk was separated by ion exchange chromatography and active complexes were only found in human casein. This was not explained by alpha-lactalbumin sequence variation, as purified bovine, equine, porcine, and caprine alpha-lactalbumins formed complexes with oleic acid with biological activity similar to HAMLET. We conclude that structural variation of alpha-lactalbumins does not preclude the formation of HAMLET-like complexes and that natural HAMLET formation in casein was unique to human milk, which also showed the highest oleic acid content.

Ink composition for making a conductive silver structure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walker, Steven B.; Lewis, Jennifer A.

An ink composition for making a conductive silver structure comprises a silver salt and a complex of (a) a complexing agent and a short chain carboxylic acid or (b) a complexing agent and a salt of a short chain carboxylic acid, according to one embodiment. A method for making a silver structure entails combining a silver salt and a complexing agent, and then adding a short chain carboxylic acid or a salt of the short chain carboxylic acid to the combined silver salt and a complexing agent to form an ink composition. A concentration of the complexing agent in themore » ink composition is reduced to form a concentrated formulation, and the silver salt is reduced to form a conductive silver structure, where the concentrated formulation and the conductive silver structure are formed at a temperature of about 120.degree. C. or less.« less

Humic Acid Complexation of Th, Hf and Zr in Ligand Competition Experiments: Metal Loading and Ph Effects

NASA Technical Reports Server (NTRS)

Stern, Jennifer C.; Foustoukos, Dionysis I.; Sonke, Jeroen E.; Salters, Vincent J. M.

2014-01-01

The mobility of metals in soils and subsurface aquifers is strongly affected by sorption and complexation with dissolved organic matter, oxyhydroxides, clay minerals, and inorganic ligands. Humic substances (HS) are organic macromolecules with functional groups that have a strong affinity for binding metals, such as actinides. Thorium, often studied as an analog for tetravalent actinides, has also been shown to strongly associate with dissolved and colloidal HS in natural waters. The effects of HS on the mobilization dynamics of actinides are of particular interest in risk assessment of nuclear waste repositories. Here, we present conditional equilibrium binding constants (Kc, MHA) of thorium, hafnium, and zirconium-humic acid complexes from ligand competition experiments using capillary electrophoresis coupled with ICP-MS (CE- ICP-MS). Equilibrium dialysis ligand exchange (EDLE) experiments using size exclusion via a 1000 Damembrane were also performed to validate the CE-ICP-MS analysis. Experiments were performed at pH 3.5-7 with solutions containing one tetravalent metal (Th, Hf, or Zr), Elliot soil humic acid (EHA) or Pahokee peat humic acid (PHA), and EDTA. CE-ICP-MS and EDLE experiments yielded nearly identical binding constants for the metal- humic acid complexes, indicating that both methods are appropriate for examining metal speciation at conditions lower than neutral pH. We find that tetravalent metals form strong complexes with humic acids, with Kc, MHA several orders of magnitude above REE-humic complexes. Experiments were conducted at a range of dissolved HA concentrations to examine the effect of [HA]/[Th] molar ratio on Kc, MHA. At low metal loading conditions (i.e. elevated [HA]/[Th] ratios) the ThHA binding constant reached values that were not affected by the relative abundance of humic acid and thorium. The importance of [HA]/[Th] molar ratios on constraining the equilibrium of MHA complexation is apparent when our estimated Kc, MHA values attained at very low metal loading conditions are compared to existing literature data. Overall, experimental data suggest that the tetravalent transition metal/-actinide-humic acid complexation is important over a wide range of pH values, including mildly acidic conditions, and thus, these complexes should be included in speciation models.

Investigation of complexes tannic acid and myricetin with Fe(III)

NASA Astrophysics Data System (ADS)

Sungur, Şana; Uzar, Atike

2008-01-01

The pH dependence of the complexes was determined by both potentiometric and spectrophotometric studies. Stability constants and stoichiometries of the formed complexes were determined using slope ratio method. Fe(III) was formed complexes with tannic acid of various stoichiometries, which in the 1:1 molar ratio at pH < 3, in the 2:1 molar ratio at pH 3-7 and in the 4:1 molar ratio at pH > 7. Fe(III) was formed complexes with myricetin in the 1:2 molar ratio at pH 4 and 5 and in the 1:1 molar ratio at pH 6. Stability constant values were found to be 10 5 to 10 17 and 10 5 to 10 9 for Fe(III)-tannic acid complexes and Fe(III)-myricetin complexes. Both tannic acid and myricetin were possessed minimum affinities to Cu(II) and Zn(II). They had less affinity for Al(III) than for Fe(III).

A one-step colorimetric acid-base titration sensor using a complementary color changing coordination system.

PubMed

Cho, Hui Hun; Kim, Si Hyun; Heo, Jun Hyuk; Moon, Young Eel; Choi, Young Hun; Lim, Dong Cheol; Han, Kwon-Hoon; Lee, Jung Heon

2016-06-21

We report the development of a colorimetric sensor that allows for the quantitative measurement of the acid content via acid-base titration in a single-step. In order to create the sensor, we used a cobalt coordination system (Co-complex sensor) that changes from greenish blue colored Co(H2O)4(OH)2 to pink colored Co(H2O)6(2+) after neutralization. Greenish blue and pink are two complementary colors with a strong contrast. As a certain amount of acid is introduced to the Co-complex sensor, a portion of greenish blue colored Co(H2O)4(OH)2 changes to pink colored Co(H2O)6(2+), producing a different color. As the ratio of greenish blue and pink in the Co-complex sensor is determined by the amount of neutralization reaction occurring between Co(H2O)4(OH)2 and an acid, the sensor produced a spectrum of green, yellow green, brown, orange, and pink colors depending on the acid content. In contrast, the color change appeared only beyond the end point for normal acid-base titration. When we mixed this Co-complex sensor with different concentrations of citric acid, tartaric acid, and malic acid, three representative organic acids in fruits, we observed distinct color changes for each sample. This color change could also be observed in real fruit juice. When we treated the Co-complex sensor with real tangerine juice, it generated diverse colors depending on the concentration of citric acid in each sample. These results provide a new angle on simple but quantitative measurements of analytes for on-site usage in various applications, such as in food, farms, and the drug industry.

Method and apparatus for purifying nucleic acids and performing polymerase chain reaction assays using an immiscible fluid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koh, Chung-Yan; Light, Yooli Kim; Piccini, Matthew Ernest

Embodiments of the present invention are directed toward devices, systems, and methods for purifying nucleic acids to conduct polymerase chain reaction (PCR) assays. In one example, a method includes generating complexes of silica beads and nucleic acids in a lysis buffer, transporting the complexes through an immiscible fluid to remove interfering compounds from the complexes, further transporting the complexes into a density medium containing components required for PCR where the nucleic acids disassociate from the silica beads, and thermocycling the contents of the density medium to achieve PCR. Signal may be detected from labeling agents in the components required formore » PCR.« less

Kinetics of acid hydrolysis and reactivity of some antibacterial hydrophilic iron(II) imino-complexes

NASA Astrophysics Data System (ADS)

Shaker, Ali Mohamed; Nassr, Lobna Abdel-Mohsen Ebaid; Adam, Mohamed Shaker Saied; Mohamed, Ibrahim Mohamed Abdelhalim

2015-05-01

Kinetic study of acid hydrolysis of some hydrophilic Fe(II) Schiff base amino acid complexes with antibacterial properties was performed using spectrophotometry. The Schiff base ligands were derived from sodium 2-hydroxybenzaldehyde-5-sulfonate and glycine, L-alanine, L-leucine, L-isoleucine, DL-methionine, DL-serine, or L-phenylalanine. The reaction was studied in aqueous media under conditions of pseudo-first order kinetics. Moreover, the acid hydrolysis was studied at different temperatures and the activation parameters were calculated. The general rate equation was suggested as follows: rate = k obs [Complex], where k obs = k 2 [H+]. The evaluated rate constants and activation parameters are consistent with the hydrophilicity of the investigated complexes.

Effects of Chain Length and Degree of Unsaturation of Fatty Acids on Structure and in Vitro Digestibility of Starch-Protein-Fatty Acid Complexes.

PubMed

Zheng, Mengge; Chao, Chen; Yu, Jinglin; Copeland, Les; Wang, Shuo; Wang, Shujun

2018-02-28

The effects of chain length and degree of unsaturation of fatty acids (FAs) on structure and in vitro digestibility of starch-protein-FA complexes were investigated in model systems. Studies with the rapid visco analyzer (RVA) showed that the formation of ternary complex resulted in higher viscosities than those of binary complex during the cooling and holding stages. The results of differential scanning calorimetry (DSC), Raman, and X-ray diffraction (XRD) showed that the structural differences for ternary complexes were much less than those for binary complexes. Starch-protein-FA complexes presented lower in vitro enzymatic digestibility compared with starch-FAs complexes. We conclude that shorter chain and lower unsaturation FAs favor the formation of ternary complexes but decrease the thermal stability of these complexes. FAs had a smaller effect on the ordered structures of ternary complexes than on those of binary complexes and little effect on enzymatic digestibility of both binary and ternary complexes.

Improving protein complex classification accuracy using amino acid composition profile.

PubMed

Huang, Chien-Hung; Chou, Szu-Yu; Ng, Ka-Lok

2013-09-01

Protein complex prediction approaches are based on the assumptions that complexes have dense protein-protein interactions and high functional similarity between their subunits. We investigated those assumptions by studying the subunits' interaction topology, sequence similarity and molecular function for human and yeast protein complexes. Inclusion of amino acids' physicochemical properties can provide better understanding of protein complex properties. Principal component analysis is carried out to determine the major features. Adopting amino acid composition profile information with the SVM classifier serves as an effective post-processing step for complexes classification. Improvement is based on primary sequence information only, which is easy to obtain. Copyright © 2013 Elsevier Ltd. All rights reserved.

Metal based pharmacologically active agents: Synthesis, structural characterization, molecular modeling, CT-DNA binding studies and in vitro antimicrobial screening of iron(II) bromosalicylidene amino acid chelates

NASA Astrophysics Data System (ADS)

Abdel-Rahman, Laila H.; El-Khatib, Rafat M.; Nassr, Lobna A. E.; Abu-Dief, Ahmed M.; Ismael, Mohamed; Seleem, Amin Abdou

2014-01-01

In recent years, great interest has been focused on Fe(II) Schiff base amino acid complexes as cytotoxic and antitumor drugs. Thus a series of new iron(II) complexes based on Schiff bases amino acids ligands have been designed and synthesized from condensation of 5-bromosalicylaldehyde (bs) and α-amino acids (L-alanine (ala), L-phenylalanine (phala), L-aspartic acid (aspa), L-histidine (his) and L-arginine (arg)). The structure of the investigated iron(II) complexes was elucidated using elemental analyses, infrared, ultraviolet-visible, thermogravimetric analysis, as well as conductivity and magnetic susceptibility measurements. Moreover, the stoichiometry and the stability constants of the prepared complexes have been determined spectrophotometrically. The results suggest that 5-bromosalicylaldehyde amino acid Schiff bases (bs:aa) behave as dibasic tridentate ONO ligands and coordinate to Fe(II) in octahedral geometry according to the general formula [Fe(bs:aa)2]ṡnH2O. The conductivity values between 37 and 64 ohm-1 mol-1 cm2 in ethanol imply the presence of nonelectrolyte species. The structure of the complexes was validated using quantum mechanics calculations based on accurate DFT methods. Geometry optimization of the Fe-Schiff base amino acid complexes showed that all complexes had octahedral coordination. In addition, the interaction of these complexes with (CT-DNA) was investigated at pH = 7.2, by using UV-vis absorption, viscosity and agarose gel electrophoresis measurements. Results indicated that the investigated complexes strongly bind to calf thymus DNA via intercalative mode and showed a different DNA binding according to the sequence: bsari > bshi > bsali > bsasi > bsphali. Moreover, the prepared compounds are screened for their in vitro antibacterial and antifungal activity against three types of bacteria, Escherichia coli, Pseudomonas aeruginosa and Bacillus cereus and three types of anti fungal cultures, Penicillium purpurogenium, Aspergillus flavus and Trichotheium rosium. The results of these studies indicated that the metal complexes exhibit a stronger antibacterial and antifungal efficiency than their corresponding Schiff base amino acid ligands.

X-ray studies on crystalline complexes involving amino acids and peptides. XXXII. Effect of chirality on ionisation state, stoichiometry and aggregation in the complexes of oxalic acid with DL- and L-lysine.

PubMed

Venkatraman, J; Prabu, M M; Vijayan, M

1997-08-01

Crystals of the oxalic acid complex of DL-lysine (triclinic P1; a = 5.540(1), b = 10.764(2), c = 12.056(2) A, alpha = 77.8(1), beta = 80.6(1), gamma = 75.6(1).; R = 4.7% for 2023 observed reflections) contain lysine and semioxalate ions in the 1:1 ratio, whereas the ratio of lysine and semioxalate/oxalate ions is 2:3 in the crystals of the L-lysine complex (monoclinic P2(1); alpha = 4.906(1), b = 20.145(4), c = 12.455(1) A, beta = 92.5(1).; R = 4.4% for 1494 observed reflections). The amino acid molecule in the L-lysine complex has an unusual ionisation state with positively charged alpha- and side-chain amino groups and a neutral carboxyl group. The unlike molecules aggregate into separate alternating layers in the DL-lysine complex in a manner similar to that observed in several of the amino acid complexes. The L-lysine complex exhibits a new aggregation pattern which cannot be easily explained in terms of planar features, thus emphasizing the fundamental dependence of aggregation on molecular characteristics. Despite the differences in stoichiometry, ionisation state and long-range aggregation patterns, the basic element of aggregation in the two complexes exhibits considerable similarity.

STUDIES ON MAMMALIAN AND HUMAN PYRUVATE AND ALPHA-KETOGLUTARATE DEHYDROGENATION COMPLEXES

DTIC Science & Technology

bound lipoic acid and 17 moles of bound FAD. Alpha -ketoglutarate dehydrogenase complex contains approximately 10 moles of protein-bound lipoic acid , 9...typical metal activators of oxidative decarboxylation reaction of alpha -keto acid . These activating effects were in good agreement with the results of...A coenzyme A- and NAD-linked pyruvate and alpha -ketoglutarate dehydrogenase complexes have been isolated from pig heart muscle as multienzyme units

Growth mechanisms of MgO nanocrystals via a sol-gel synthesis using different complexing agents

PubMed Central

2014-01-01

In the preparation of nanostructured materials, it is important to optimize synthesis parameters in order to obtain the desired material. This work investigates the role of complexing agents, oxalic acid and tartaric acid, in the production of MgO nanocrystals. Results from simultaneous thermogravimetric analysis (STA) show that the two different synthesis routes yield precursors with different thermal profiles. It is found that the thermal profiles of the precursors can reveal the effects of crystal growth during thermal annealing. X-ray diffraction confirms that the final products are pure, single phase and of cubic shape. It is also found that complexing agents can affect the rate of crystal growth. The structures of the oxalic acid and tartaric acid as well as the complexation sites play very important roles in the formation of the nanocrystals. The complexing agents influence the rate of growth which affects the final crystallite size of the materials. Surprisingly, it is also found that oxalic acid and tartaric acid act as surfactants inhibiting crystal growth even at a high temperature of 950°C and a long annealing time of 36 h. The crystallite formation routes are proposed to be via linear and branched polymer networks due to the different structures of the complexing agents. PMID:24650322

Self nanoemulsifying drug delivery system of stabilized ellagic acid-phospholipid complex with improved dissolution and permeability.

PubMed

Avachat, Amelia M; Patel, Vijay G

2015-07-01

Ellagic acid (EA), a plant polyphenol known for its wide-range of health benefits has limited use due to its low oral bioavailability. In this study, a new self-nanoemulsifying drug delivery system (SNEDDS), based on the phospholipid complex technique, was developed to improve the oral bioavailability of ellagic acid. Ellagic acid-phospholipid complex was prepared by an anti-solvent method and characterized. Enhanced lipophilicity after the formation of ellagic acid-phospholipid complex was verified through solubility studies. Preliminary screening was carried out to select oil, surfactant and co-surfactant. Ternary phase diagrams were constructed to identify the area of nanoemulsification. Formulations were optimized on the basis of globule size, cloud point and robustness to dilution. The optimized SNEDDS of ellagic acid-phospholipid complex showed mean globule size of 106 ± 0.198 nm and cloud point at 83-85 °C. The in vitro drug release from SNEDDS was found to be higher compared to EA suspension and complex, while ex vivo studies showed increased permeation from SNEDDS compared to EA suspension. Moreover, SNEDDS overcome the food effect which was shown by EA suspension. Thus, SNEDDS were found to be influential in improving the release performance of EA, indicating their potential to improve the oral bioavailability of EA.

Quantum chemical density functional theory studies on the molecular structure and vibrational spectra of Gallic acid imprinted polymers

NASA Astrophysics Data System (ADS)

Pardeshi, Sushma; Dhodapkar, Rita; Kumar, Anupama

2013-12-01

Gallic acid (GA) is known by its antioxidant, anticarcinogenic properties and scavenger activity against several types of harmful free radicals. Molecularly imprinted polymers (MIPs) are used in separation of a pure compound from complex matrices. A stable template-monomer complex generates the MIPs with the highest affinity and selectivity for the template. The quantum chemical computations based on density functional theory (DFT) was used on the template Gallic acid (GA), monomer acrylic acid (AA) and GA-AA complex to study the nature of interactions involved in the GA-AA complex. B3LYP/6-31+G(2d,2p) model chemistry was used to optimize their structures and frequency calculations. The effect of porogen acetonitrile (ACN) on complex formation was included by using polarizable continuum model (PCM). The results demonstrated the formation of a stable GA-AA complex through the intermolecular hydrogen bonding between carboxylic acid groups of GA and AA. The Mulliken atomic charge analysis and simulated vibrational spectra also supported the stable hydrogen bonding interaction between the carboxylic acid groups of GA and AA with minimal interference of porogen ACN. Further, simulations on GA-AA mole ratio revealed that 1:4 GA-AA was optimum for synthesis of MIP for GA.

Study of Nanocomposites of Amino Acids and Organic Polyethers by Means of Mass Spectrometry and Molecular Dynamics Simulation

NASA Astrophysics Data System (ADS)

Zobnina, V. G.; Kosevich, M. V.; Chagovets, V. V.; Boryak, O. A.

A problem of elucidation of structure of nanomaterials based on combination of proteins and polyether polymers is addressed on the monomeric level of single amino acids and oligomers of PEG-400 and OEG-5 polyethers. Efficiency of application of combined approach involving experimental electrospray mass spectrometry and computer modeling by molecular dynamics simulation is demonstrated. It is shown that oligomers of polyethers form stable complexes with amino acids valine, proline, histidine, glutamic, and aspartic acids. Molecular dynamics simulation has shown that stabilization of amino acid-polyether complexes is achieved due to winding of the polymeric chain around charged groups of amino acids. Structural motives revealed for complexes of single amino acids with polyethers can be realized in structures of protein-polyether nanoparticles currently designed for drug delivery.

APPLICATION OF FORMOHYDROXAMIC ACID IN NUCLEAR PROCESSING: SYNTHESIS AND COMPLEXATION WITH TECHNETIUM-99

DOE Office of Scientific and Technical Information (OSTI.GOV)

Amber Wright; Edward Mausolf; Keri Campbell

2010-05-01

Acetohydroxamic acid (AHA) is an organic ligand planned for use in the Uranium Extraction (UREX) process. It reduces neptunium and plutonium, and the resultant hydrophilic complexes are separated from uranium by extraction with tributyl phosphate (TBP) in a hydrocarbon diluent. AHA undergoes hydrolysis to acetic acid which will impede the recycling of nitric acid. During recent discussions of the UREX process, it has been proposed to replace AHA by formohydroxamic acid (FHA). FHA will undergo hydrolysis to formic acid which is volatile, thus allowing the recycling of nitric acid. The reported reduction potentials of AHA and pertechnetate (TcO{sub 4}{sup -})more » indicated that it may be possible for AHA to reduce technetium, altering its fate in the fuel cycle. At UNLV, it has been demonstrated that TcO{sub 4}{sup -} undergoes reductive nitrosylation by AHA under a variety of conditions. The resulting divalent technetium is complexed by AHA to form the pseudo-octahedral trans-aquonitrosyl (diacetohydroxamic)-technetium(II) complex ([Tc{sup II}(NO)(AHA){sub 2}H{sub 2}O]{sup +}). In this paper, we are reporting the synthesis of FHA and its complex formation with technetium along with the characterization of FHA crystals achieved by NMR and IR spectroscopy. Two experiments were conducted to investigate the complexation of FHA with Tc and the results were compared with previous data on AHA. The first experiment involved the elution of Tc from a Reillex HP anion exchange resin, and the second one monitored the complexation of technetium with FHA by UV-visible spectrophotometry.« less

Ionic complexation as a non-covalent approach for the design of folate anchored rifampicin Gantrez nanoparticles.

PubMed

Date, Praveen V; Patel, Mitesh D; Majee, Sharmila B; Samad, Abdul; Devarajan, Padma V

2013-05-01

The present study discloses the design of folate anchored Rifampicin-Poly methylvinylether maleic anhydride copolymer (Gantrez AN-119, Gantrez) nanoparticles (RFMGzFa) by ionic complexation. Folic acid was anchored to the preformed drug loaded nanoparticles. Folic acid was anchored in different concentration by simply varying the amount of folic acid added during preparation. RFMGzFa nanoparticles were prepared by emulsion solvent diffusion method. Gantrez AN-119 rapidly hydrolyzes in aqueous medium releasing carboxylic acid groups, to create an acidic environment. This facilitates protonation and subsequent ionic complexation of folic acid with the carboxylic groups, to enable anchoring. FTIR spectra confirmed this interaction. Infrared imaging revealed distribution of folic acid across the nanoparticle surface. Nanoparticles were obtained in the size range 350-450 nm with RFM loading of 12-14% w/w. Zeta potential confirmed colloidal stability. TEM/SEM revealed spherical morphology. RFMGzFa nanoparticles exhibited sustained release of RFM and folic acid. Folic acid showed sustained release upto 12 h, which was ion exchange mediated. A 480% enhancement in RFM uptake with RFMGzFa nanoparticles compared to 300% with RFMGz nanoparticles in-vitro, in human macrophage cell line U-937, suggested the role of folic acid in folate receptor mediated uptake. Ionic complexation represents a simple non-covalent approach for anchoring folic acid on polymeric nanoparticles of Gantrez.

Study of structural, surface and hydrogen storage properties of boric acid mediated metal (sodium)-organic frameworks

NASA Astrophysics Data System (ADS)

Ozer, Demet; Köse, Dursun A.; Sahin, Onur; Oztas, Nursen A.

2018-04-01

Three boric acid mediated metal organic frameworks were synthesized by solution method with using succinic acid, fumaric acid and acetylene dicarboxylic acid as a ligand source and sodium as a metal source. The complexes were characterized by FT-IR, powder XRD, elemental analyses and single crystal measurements. The complexes with the formula, C4H18B2Na2O14, C4H16B2Na2O14 and C4H14B2Na2O14 were successfully obtained. BET surface area of complexes were calculated and found as 13.474 m2/g for catena-(tetrakis(μ2-hydroxo)-(μ2-trihydrogen borate)-(μ2-succinato)-di-sodium boric acid solvate), 1.692 m2/g for catena-(tetrakis(μ2-hydroxo)-(μ2-trihydrogen borate)-(μ2-fumarato)-di-sodium boric acid solvate) and 5.600 m2/g for catena-(tetrakis(μ2-hydroxo)-(μ2-trihydrogen borate)-(μ2-acetylenedicarboxylato)-di-sodium boric acid solvate). Hydrogen storage capacities of the complexes were also studied at 77 K 1 bar pressure and found as 0.108%, 0.033%, 0.021% by mass. When different ligands were used, the pore volume, pore width and surface area of the obtained complexes were changed. As a consequence, hydrogen storage capacities also changed.

Synthesis, structure and stability of a chiral imine-based Schiff-based ligand derived from L-glutamic acid and its [Cu4] complex

NASA Astrophysics Data System (ADS)

Muche, Simon; Levacheva, Irina; Samsonova, Olga; Biernasiuk, Anna; Malm, Anna; Lonsdale, Richard; Popiołek, Łukasz; Bakowsky, Udo; Hołyńska, Małgorzata

2017-01-01

Studies of the stability of a ligand derived from L-glutamic acid and ortho-vanillin and its new [Cu4] complex are presented. The [Cu4] complex contains a heterocubane [CuII4O4] core and pendant carboxylic groups increasing its solubility in water, also under basic conditions. The stability of the complex in different solvents is confirmed with ESI-MS studies and such experiments as successful recrystallization. The complex is stable also under physiological conditions whereas the ligand is partly decomposed to L-glutamic acid and ortho-vanillin.

Single-stranded nucleic acids promote SAMHD1 complex formation.

PubMed

Tüngler, Victoria; Staroske, Wolfgang; Kind, Barbara; Dobrick, Manuela; Kretschmer, Stefanie; Schmidt, Franziska; Krug, Claudia; Lorenz, Mike; Chara, Osvaldo; Schwille, Petra; Lee-Kirsch, Min Ae

2013-06-01

SAM domain and HD domain-containing protein 1 (SAMHD1) is a dGTP-dependent triphosphohydrolase that degrades deoxyribonucleoside triphosphates (dNTPs) thereby limiting the intracellular dNTP pool. Mutations in SAMHD1 cause Aicardi-Goutières syndrome (AGS), an inflammatory encephalopathy that mimics congenital viral infection and that phenotypically overlaps with the autoimmune disease systemic lupus erythematosus. Both disorders are characterized by activation of the antiviral cytokine interferon-α initiated by immune recognition of self nucleic acids. Here we provide first direct evidence that SAMHD1 associates with endogenous nucleic acids in situ. Using fluorescence cross-correlation spectroscopy, we demonstrate that SAMHD1 specifically interacts with ssRNA and ssDNA and establish that nucleic acid-binding and formation of SAMHD1 complexes are mutually dependent. Interaction with nucleic acids and complex formation do not require the SAM domain, but are dependent on the HD domain and the C-terminal region of SAMHD1. We finally demonstrate that mutations associated with AGS exhibit both impaired nucleic acid-binding and complex formation implicating that interaction with nucleic acids is an integral aspect of SAMHD1 function.

Identification of Nucleic Acid Binding Sites on Translin-Associated Factor X (TRAX) Protein

PubMed Central

Gupta, Gagan Deep; Kumar, Vinay

2012-01-01

Translin and TRAX proteins play roles in very important cellular processes such as DNA recombination, spatial and temporal expression of mRNA, and in siRNA processing. Translin forms a homomeric nucleic acid binding complex and binds to ssDNA and RNA. However, a mutant translin construct that forms homomeric complex lacking nucleic acid binding activity is able to form fully active heteromeric translin-TRAX complex when co-expressed with TRAX. A substantial progress has been made in identifying translin sites that mediate its binding activity, while TRAX was thought not to bind DNA or RNA on its own. We here for the first time demonstrate nucleic acid binding to TRAX by crosslinking radiolabeled ssDNA to heteromeric translin-TRAX complex using UV-laser. The TRAX and translin, photochemically crosslinked with ssDNA, were individually detected on SDS-PAGE. We mutated two motifs in TRAX and translin, designated B2 and B3, to help define the nucleic acid binding sites in the TRAX sequence. The most pronounced effect was observed in the mutants of B3 motif that impaired nucleic acid binding activity of the heteromeric complexes. We suggest that both translin and TRAX are binding competent and contribute to the nucleic acid binding activity. PMID:22427937

21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

Code of Federal Regulations, 2013 CFR

2013-04-01

... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.315 Nicotinamide-ascorbic acid complex...: (a) The additive is the product of the controlled reaction between ascorbic acid and nicotinamide...

21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

Code of Federal Regulations, 2012 CFR

2012-04-01

... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.315 Nicotinamide-ascorbic acid complex...: (a) The additive is the product of the controlled reaction between ascorbic acid and nicotinamide...

Complex compound polyvinyl alcohol-titanic acid/titanium dioxide

NASA Astrophysics Data System (ADS)

Prosanov, I. Yu.

2013-02-01

A complex compound polyvinyl alcohol-titanic acid has been produced and investigated by means of IR and Raman spectroscopy, X-ray diffraction, and synchronous thermal analysis. It is claimed that it represents an interpolymeric complex of polyvinyl alcohol and hydrated titanium oxide.

Refinement of Generalized Born Implicit Solvation Parameters for Nucleic Acids and their Complexes with Proteins

PubMed Central

Nguyen, Hai; Pérez, Alberto; Bermeo, Sherry; Simmerling, Carlos

2016-01-01

The Generalized Born (GB) implicit solvent model has undergone significant improvements in accuracy for modeling of proteins and small molecules. However, GB still remains a less widely explored option for nucleic acid simulations, in part because fast GB models are often unable to maintain stable nucleic acid structures, or they introduce structural bias in proteins, leading to difficulty in application of GB models in simulations of protein-nucleic acid complexes. Recently, GB-neck2 was developed to improve the behavior of protein simulations. In an effort to create a more accurate model for nucleic acids, a similar procedure to the development of GB-neck2 is described here for nucleic acids. The resulting parameter set significantly reduces absolute and relative energy error relative to Poisson Boltzmann for both nucleic acids and nucleic acid-protein complexes, when compared to its predecessor GB-neck model. This improvement in solvation energy calculation translates to increased structural stability for simulations of DNA and RNA duplexes, quadruplexes, and protein-nucleic acid complexes. The GB-neck2 model also enables successful folding of small DNA and RNA hairpins to near native structures as determined from comparison with experiment. The functional form and all required parameters are provided here and also implemented in the AMBER software. PMID:26574454

Metal-organic complexes in geochemical processes: temperature dependence of the standard thermodynamic properties of aqueous complexes between metal cations and dicarboxylate ligands

NASA Astrophysics Data System (ADS)

Prapaipong, Panjai; Shock, Everett L.; Koretsky, Carla M.

1999-10-01

By combining results from regression and correlation methods, standard state thermodynamic properties for aqueous complexes between metal cations and divalent organic acid ligands (oxalate, malonate, succinate, glutarate, and adipate) are evaluated and applied to geochemical processes. Regression of experimental standard-state equilibrium constants with the revised Helgeson-Kirkham-Flowers (HKF) equation of state yields standard partial molal entropies (S¯°) of aqueous metal-organic complexes, which allow determination of thermodynamic properties of the complexes at elevated temperatures. In cases where S¯° is not available from either regression or calorimetric measurement, the values of S¯° can be estimated from a linear correlation between standard partial molal entropies of association (ΔS¯°r) and standard partial molal entropies of aqueous cations (S¯°M). The correlation is independent of cation charge, which makes it possible to predict S¯° for complexes between divalent organic acids and numerous metal cations. Similarly, correlations between standard Gibbs free energies of association of metal-organic complexes (ΔḠ°r) and Gibbs free energies of formation (ΔḠ°f) for divalent metal cations allow estimates of standard-state equilibrium constants where experimental data are not available. These correlations are found to be a function of ligand structure and cation charge. Predicted equilibrium constants for dicarboxylate complexes of numerous cations were included with those for inorganic and other organic complexes to study the effects of dicarboxylate complexes on the speciation of metals and organic acids in oil-field brines. Relatively low concentrations of oxalic and malonic acids affect the speciation of cations more than similar concentrations of succinic, glutaric, and adipic acids. However, the extent to which metal-dicarboxylate complexes contribute to the speciation of dissolved metals depends on the type of dicarboxylic acid ligand; relative concentration of inorganic, mono-, and dicarboxylate ligands; and the type of metal cation. As an example, in the same solution, dicarboxylic acids have a greater influence on the speciation of Fe+2 and Mg+2 than on the speciation of Zn+2 and Mn+2.

Evaluating the role of acidic, basic, and polar amino acids and dipeptides on a molecular electrocatalyst for H 2 oxidation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boralugodage, Nilusha Priyadarshani; Arachchige, Rajith Jayasingha; Dutta, Arnab

Amino acids and peptides have been shown to have a significant influence on the H2 production and oxidation reactivity of Ni(P R 2N R’ 2) 2, where P R 2N R’ 2 = 1,5-diaza-3,7-diphosphacyclooctane, R is either phenyl (Ph) or cyclohexyl (Cy), and R’ is either an amino acid or peptide. Most recently, the Ni(P Cy 2Naminoacid 2) 2 complexes (CyAA) have shown enhanced H 2 oxidation rates, water solubility, and in the case of arginine (CyArg) and phenylalanine (CyPhe), electrocatalytic reversibility. Both the backbone –COOH and side chain interactions were shown to be critical to catalytic performance. Here wemore » further investigate the roles of the outer coordination sphere by evaluating amino acids with acidic, basic, and hydrophilic side chains, as well as dipeptides which combine multiple successful features from previous complexes. Six new complexes were prepared, three containing single amino acids: aspartic acid (CyAsp), lysine (CyLys), and serine (CySer) and three containing dipeptides: glycine-phenylalanine (Cy(GlyPhe)), phenylalanine-glycine (Cy(PheGly)), and aspartic acid-phenylananine (Cy(AspPhe)). The resulting catalytic performance demonstrates that complexes need both interactions between side chain and –COOH groups for fast, efficient catalysis. The fastest of all of the catalysts, Cy(AspPhe), had both of these features, while the other dipeptide complexes with an amide replacing the -COOH were both slower; however, the amide group was demonstrated to participate in the proton pathway when side chain interactions are present to position it. Both the hydrophilic and basic side chains, notably lacking in side chain interactions, significantly increased the overpotential, with only modest increases in TOF. Of all of the complexes, only CyAsp was reversible at room temperature, and only in water, the first of these complexes to demonstrate room temperature reversibility in water. These results continue to provide and solidify design rules for controlling reactivity and efficiency of Ni(P 2N 2) 2 complexes with the outer coordination sphere.« less

Oxalate metal complexes in aerosol particles: implications for the hygroscopicity of oxalate-containing particles

NASA Astrophysics Data System (ADS)

Furukawa, T.; Takahashi, Y.

2011-05-01

Atmospheric aerosols have both a direct and an indirect cooling effect that influences the radiative balance at the Earth's surface. It has been estimated that the degree of cooling is large enough to weaken the warming effect of carbon dioxide. Among the cooling factors, secondary organic aerosols (SOA) play an important role in the solar radiation balance in the troposphere as SOA can act as cloud condensation nuclei (CCN) and extend the lifespan of clouds because of their high hygroscopic and water soluble nature. Oxalic acid is an important component of SOA, and is produced via several formation pathways in the atmosphere. However, it is not certain whether oxalic acid exists as free oxalic acid or as metal oxalate complexes in aerosols, although there is a marked difference in their solubility in water and their hygroscopicity. We employed X-ray absorption fine structure spectroscopy to characterize the calcium (Ca) and zinc (Zn) in aerosols collected at Tsukuba in Japan. Size-fractionated aerosol samples were collected for this purpose using an impactor aerosol sampler. It was shown that 10-60% and 20-100% of the total Ca and Zn in the finer particles (<2.1 μm) were present as Ca and Zn oxalate complexes, respectively. Oxalic acid is hygroscopic and can thus increase the CCN activity of aerosol particles, while complexes with various polyvalent metal ions such as Ca and Zn are not hygroscopic, which cannot contribute to the increase of the CCN activity of aerosols. Based on the concentrations of noncomplexed and metal-complexed oxalate species, we found that most of the oxalic acid is present as metal oxalate complexes in the aerosols, suggesting that oxalic acid does not always increase the hygroscopicity of aerosols in the atmosphere. Similar results are expected for other dicarboxylic acids, such as malonic and succinic acids. Thus, it is advisable that the cooling effect of organic aerosols should be estimated by including the information on metal oxalate complexes and metal complexes with other dicarboxylic acids in aerosols.

Base-free production of H2 by dehydrogenation of formic acid using an iridium-bisMETAMORPhos complex.

PubMed

Oldenhof, Sander; de Bruin, Bas; Lutz, Martin; Siegler, Maxime A; Patureau, Frederic W; van der Vlugt, Jarl Ivar; Reek, Joost N H

2013-08-26

Erase the base: An iridium complex based on a cooperative ligand that functions as an internal base is reported. This complex can rapidly and cleanly dehydrogenate formic acid in absence of external base, a reaction that is required if formic acid is to be exploited as an energy carrier (see scheme). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Exercise promotes BCAA catabolism: effects of BCAA supplementation on skeletal muscle during exercise.

PubMed

Shimomura, Yoshiharu; Murakami, Taro; Nakai, Naoya; Nagasaki, Masaru; Harris, Robert A

2004-06-01

Branched-chain amino acids (BCAAs) are essential amino acids that can be oxidized in skeletal muscle. It is known that BCAA oxidation is promoted by exercise. The mechanism responsible for this phenomenon is attributed to activation of the branched-chain alpha-keto acid dehydrogenase (BCKDH) complex, which catalyzes the second-step reaction of the BCAA catabolic pathway and is the rate-limiting enzyme in the pathway. This enzyme complex is regulated by a phosphorylation-dephosphorylation cycle. The BCKDH kinase is responsible for inactivation of the complex by phosphorylation, and the activity of the kinase is inversely correlated with the activity state of the BCKDH complex, which suggests that the kinase is the primary regulator of the complex. We found recently that administration of ligands for peroxisome proliferator-activated receptor-alpha (PPARalpha) in rats caused activation of the hepatic BCKDH complex in association with a decrease in the kinase activity, which suggests that promotion of fatty acid oxidation upregulates the BCAA catabolism. Long-chain fatty acids are ligands for PPARalpha, and the fatty acid oxidation is promoted by several physiological conditions including exercise. These findings suggest that fatty acids may be one of the regulators of BCAA catabolism and that the BCAA requirement is increased by exercise. Furthermore, BCAA supplementation before and after exercise has beneficial effects for decreasing exercise-induced muscle damage and promoting muscle-protein synthesis; this suggests the possibility that BCAAs are a useful supplement in relation to exercise and sports.

The kinetics of lanthanide complexation by EDTA and DTPA in lactate media.

PubMed

Nash, K L; Brigham, D; Shehee, T C; Martin, A

2012-12-28

The interaction of trivalent lanthanide and actinide cations with polyaminopolycarboxylic acid complexing agents in lactic acid buffer systems is an important feature of the chemistry of the TALSPEAK process for the separation of trivalent actinides from lanthanides. To improve understanding of metal ion coordination chemistry in this process, the results of an investigation of the kinetics of lanthanide complexation by ethylenediamine-N,N,N',N'-tetraacetic acid (EDTA) and diethylenetriamine-N,N,N',N'',N''-pentaacetic acid (DTPA) in 0.3 M lactic acid/0.3 M ionic strength solution are reported. Progress of the reaction was monitored using the distinctive visible spectral changes attendant to lanthanide complexation by the colorimetric indicator ligand Arsenazo III, which enables the experiment but plays no mechanistic role. Under the conditions of these experiments, the reactions occur in a time regime suitable for study by stopped-flow spectrophotometric techniques. Experiments have been conducted as a function of EDTA/DTPA ligand concentration, total lactic acid concentration, and pH. The equilibrium perturbation reaction proceeds as a first order approach to equilibrium over a wide range of conditions, allowing the simultaneous determination of complex formation and dissociation rate constants. The rate of the complexation reaction has been determined for the entire lanthanide series (except Pm(3+)). The predominant pathway for lanthanide-EDTA and lanthanide-DTPA dissociation is inversely dependent on the total lactate concentration; the complex formation reaction demonstrates a direct dependence on [H(+)]. Unexpectedly, the rate of the complex formation reaction is seen in both ligand systems to be fastest for Gd(3+). Correlation of these results indicates that in 0.3 M lactate solutions the exchange of lanthanide ions between lactate complexes and the polyaminopolycarboxylate govern the process.

A recyclable Au(I) catalyst for selective homocoupling of arylboronic acids: significant enhancement of nano-surface binding for stability and catalytic activity.

PubMed

Zhang, Xin; Zhao, Haitao; Wang, Jianhui

2010-08-01

Au nanoparticles stabilized by polystyrene-co-polymethacrylic acid microspheres (PS-co-PMAA) were prepared and characterized via X-ray diffraction (XRD), and transmission electron microscope (TEM). The Au nanoparticles supported on the microspheres showed highly selective catalytic activity for homo-coupling reactions of arylboronic acids in a system of aryl-halides and arylboronic acids. X-ray photoelectron spectroscopy (XPS) spectra of the catalyst shows large amounts of Au(I) complexes band to the surface of the Au nanoparticles, which contributes to the selective homocoupling of the arylboronic acids. More importantly, this supported Au complex is a highly recyclable catalyst. The supported Au catalyst can be recycled and reused at least 6 times for a phenylboronic acid reactant, whereas the parent complex shows very low catalytic activity for this compound. The high catalytic activity of this material is attributed to: (1) the high surface to volume ratio which leads to more active sites being exposed to reactants; (2) the strong surface binding of the Au nanoparticle to the Au(I) complexes, which enhances both the stability and the catalytic activity of these complexes.

The dissolution of quartz in dilute aqueous solutions of organic acids at 25°C

USGS Publications Warehouse

Bennett, P.C.; Melcer, M.E.; Siegel, D.I.; Hassett, J.P.

1988-01-01

The dissolution of quartz in dilute aqueous solutions of organic acids at 25° and standard pressure was investigated by the batch dissolution method. The bulk dissolution rate of quartz in 20 mmole/Kg citrate solutions at pH 7 was 8 to 10 times faster than that in pure water. After 1750 hours the concentration of dissolved silica in the citrate solution was 167 μmole/Kg compared to 50 μmole/Kg in water and a 20 mmole/Kg solution of acetate at pH 7. Solutions of salicylic, oxalic, and humic acids also accelerated the dissolution of quartz in aqueous solution at pH 7. The rate of dissolution in organic acids decreased sharply with decreasing pH.The possibility of a silica-organic acid complex was investigated using UV-difference spectroscopy. Results suggest that dissolved silica is complexed by citrate, oxalate and pyruvate at pH 7 by an electron-donor acceptor complex, whereas no complexation occurs between silica and acetate, lactate, malonate, or succinate. Three models are proposed for the solution and surface complexation of silica by organic acid anions which result in the accelerated dissolution and increased solubility of quartz in organic rich water.

Introduction to fatty acids and lipids.

PubMed

Burdge, Graham C; Calder, Philip C

2015-01-01

The purpose of this article is to describe the structure, function and metabolism of fatty acids and lipids that are of particular importance in the context of parenteral nutrition. Lipids are a heterogeneous group of molecules that share the common property of hydrophobicity. Lipids range in structure from simple short hydrocarbon chains to more complex molecules, including triacylglycerols, phospholipids and sterols and their esters. Lipids within each class may differ structurally. Fatty acids are common components of complex lipids, and these differ according to chain length and the presence, number and position of double bonds in the hydrocarbon chain. Structural variation among complex lipids and among fatty acids gives rise to functional differences that result in different impacts upon metabolism and upon cell and tissue responses. Fatty acids and complex lipids exhibit a variety of structural variations that influence their metabolism and their functional effects. © 2015 S. Karger AG, Basel.

A Cysteine Substitution Probes β3H267 Interactions with Propofol and Other Potent Anesthetics in α1β3γ2L Gamma-Aminobutyric Acid Type A Receptors

PubMed Central

Stern, Alex T.; Forman, Stuart A.

2015-01-01

Background Anesthetic contact residues in γ-aminobutyric acid type A (GABAA) receptors have been identified using photolabels, including two propofol derivatives. O-propofol-diazirine labels H267 in β3 and α1β3 receptors, while m-azi-propofol labels other residues in intersubunit clefts of α1β3. Neither label has been studied in αβγ receptors, the most common isoform in mammalian brain. In αβγ receptors, other anesthetic derivatives photolabel m-azi-propofol labeled residues, but not βH267. Our structural homology model of α1β3γ2L receptors suggests that β3H267 may abut some of these sites. Methods Substituted cysteine modification-protection was used to test β3H267C interactions with four potent anesthetics: propofol, etomidate, alphaxalone, and R-5-allyl-1-methyl-5-(m-trifluoromethyl-diazirinylphenyl) barbituric acid (mTFD-MPAB). We expressed α1β3γ2L or α1β3H267Cγ2L GABAA receptors in Xenopus oocytes. We used voltage clamp electrophysiology to assess receptor sensitivity to GABA and anesthetics, and to compare para-chloromercuribenzenesulfonate (pCMBS) modification rates with GABA versus GABA plus anesthetics. Results Enhancement of GABA EC5 responses by equi-hypnotic concentrations of all four anesthetics was similar in α1β3γ2L and α1β3H267Cγ2L receptors (n ≥ 3). Direct activation of α1β3H267Cγ2L receptors, but not α1β3γ2L, by mTFD-MPAB and propofol was significantly greater than the other anesthetics. Modification of β3H267C by pCMBS (n ≥ 4) was rapid and accelerated by GABA. Only mTFD-MPAB slowed β3H267C modification (~2-fold; p = 0.011). Conclusions β3H267 in α1β3γ2L GABAA receptors contacts mTFD-MPAB, but not propofol. Our results suggest that β3H267 is near the periphery of one or both transmembrane inter-subunit (α+/β− and γ+/β−) pockets where both mTFD-MPAB and propofol bind. PMID:26569173

Opiate addiction in adult offspring through possible imprinting after obstetric treatment.

PubMed Central

Jacobson, B; Nyberg, K; Grönbladh, L; Eklund, G; Bygdeman, M; Rydberg, U

1990-01-01

OBJECTIVE--To test the hypothesis that opiate addiction in adults might stem partly from an imprinting process during birth when certain drugs are given to the mother. DESIGN--Retrospective study by logistic regression of opiate addicts with siblings as controls. SETTING--Stockholm, Sweden. SUBJECTS--200 Opiate addicts born in Stockholm during 1945-66, comprising 41 identified during interviews of probands for an earlier study; 75 patients whose death from opiate addiction had been confirmed during 1978-88; and 84 accepted for the methadone programme. 262 Siblings (controls) born in Stockholm during the same period, 24 of whom were excluded for drug addiction or being brought up outside the family. Birth records were unavailable for eight, leaving 230 siblings and 139 corresponding probands. MAIN OUTCOME MEASURES--Administration of opiates, barbiturates, and nitrous oxide (for greater than 1 h) to mothers of all subjects during labour within 10 hours before birth as a risk factor for adult opiate addiction. RESULTS--In subjects who had subsequently become addicts a significant proportion of mothers had received opiates or barbiturates, or both, compared with unmatched siblings (25% v 16%, chi 2 = 5.83, df = 1, p = 0.02), and these mothers had received nitrous oxide for longer and more often. After controlling for hospital of birth, order of birth, duration of labour, presentation other than vertex, surgical intervention, asphyxia, meconium stained amniotic fluid, and birth weight the relative risk for offspring subsequently becoming an adult opiate addict increased with the number of administrations of any of the three drugs. When the addicts were matched with their own siblings the estimated relative risk was 4.7 (95% confidence interval 1.8 to 12.4, p for trend = 0.002) for three administrations compared with when no drug was given. CONCLUSIONS--The results are compatible with the imprinting hypothesis. Therefore, for obstetric pain relief methods are preferable that do not permit substantial passage of drugs through the placenta. PMID:2249068

Pharmacologic Treatment Reduces Pressure Times Time Dose and Relative Duration of Intracranial Hypertension.

PubMed

Colton, Katharine; Yang, S; Hu, P F; Chen, H H; Bonds, B; Stansbury, L G; Scalea, T M; Stein, D M

2016-05-01

Past work has shown the importance of the "pressure times time dose" (PTD) of intracranial hypertension (intracranial pressure [ICP] > 19 mm Hg) in predicting outcome after severe traumatic brain injury. We used automated data collection to measure the effect of common medications on the duration and dose of intracranial hypertension. Patients >17 years old, admitted and requiring ICP monitoring between 2008 and 2010 at a single, large urban tertiary care facility, were retrospectively enrolled. Timing and dose of ICP-directed therapy were recorded from paper and electronic medical records. The ICP data were collected automatically at 6-second intervals and averaged over 5 minutes. The percentage of time of intracranial hypertension (PTI) and PTD (mm Hg h) were calculated. A total of 98 patients with 664 treatment instances were identified. Baseline PTD ranged from 27 (before administration of propofol and fentanyl) to 150 mm Hg h (before mannitol). A "small" dose of hypertonic saline (HTS; ≤250 mL 3%) reduced PTD by 38% in the first hour and 37% in the second hour and reduced the time with ICP >19 by 38% and 39% after 1 and 2 hours, respectively. A "large" dose of HTS reduced PTD by 40% in the first hour and 63% in the second (PTI reduction of 36% and 50%, respectively). An increased dose of propofol or fentanyl infusion failed to decrease PTD but reduced PTI between 14% (propofol alone) and 30% (combined increase in propofol and fentanyl, after 2 hours). Barbiturates failed to decrease PTD but decreased PTI by 30% up to 2 hours after administration. All reductions reported are significantly changed from baseline, P < .05. Baseline PTD values before drug administration reflects varied patient criticality, with much higher values seen before the use of mannitol or barbiturates. Treatment with HTS reduced PTD and PTI burden significantly more than escalation of sedation or pain management, and this effect remained significant at 2 hours after administration. © The Author(s) 2014.

A Comparison of Pharmacologic Therapeutic Agents Used for the Reduction of Intracranial Pressure After Traumatic Brain Injury.

PubMed

Alnemari, Ahmed M; Krafcik, Brianna M; Mansour, Tarek R; Gaudin, Daniel

2017-10-01

In neurotrauma care, a better understanding of treatments after traumatic brain injury (TBI) has led to a significant decrease in morbidity and mortality in this population. TBI represents a significant medical problem, and complications after TBI are associated with the initial injury and postevent intracranial processes such as increased intracranial pressure and brain edema. Consequently, appropriate therapeutic interventions are required to reduce brain tissue damage and improve cerebral perfusion. We present a contemporary review of literature on the use of pharmacologic therapies to reduce intracranial pressure after TBI and a comparison of their efficacy. This review was conducted by PubMed query. Only studies discussing pharmacologic management of patients after TBI were included. This review includes prospective and retrospective studies and includes randomized controlled trials as well as cohort, case-control, observational, and database studies. Systematic literature reviews, meta-analyses, and studies that considered conditions other than TBI or pediatric populations were not included. Review of the literature describing the current pharmacologic treatment for intracranial hypertension after TBI most often discussed the use of hyperosmolar agents such as hypertonic saline and mannitol, sedatives such as fentanyl and propofol, benzodiazepines, and barbiturates. Hypertonic saline is associated with faster resolution of intracranial hypertension and restoration of optimal cerebral hemodynamics, although these advantages did not translate into long-term benefits in morbidity or mortality. In patients refractory to treatment with hyperosmolar therapy, induction of a barbiturate coma can reduce intracranial pressure, although requires close monitoring to prevent adverse events. Current research suggests that the use of hypertonic saline after TBI is the best option for immediate decrease in intracranial pressure. A better understanding of the efficacy of each treatment option can help to direct treatment algorithms during the critical early hours of trauma care and continue to improve morbidity and mortality after TBI. Copyright © 2017 Elsevier Inc. All rights reserved.

Nuclear medicine technology progress report for quarter ending September 30, 1980

DOE Office of Scientific and Technical Information (OSTI.GOV)

Knapp, F.F. Jr.

1981-03-01

Brain uptake of several /sup 75/Se- and /sup 123m/Te-labelled barbiturates is being studied. These new agents, substituted at the C-5 position, freely pass through the intact blood-brain barrier. Barbiturates labelled with gamma-emitting radionuclides may be an attractive new class of agents for measurement of regional cerebral blood flow. The diffusion chamber assay system has been used to assess the chronic effects of As/sub 2/O/sub 3/ toxicity. A small osmotically actuated minipump was used to deliver aqueous As/sub 2/O/sub 3/ at a continuous delivery rate to animals having intraperitoneally implanted diffusion chambers containing human lung cells (Flow 200). In these preliminarymore » studies, a 49 to 53% inhibition of cell growth was observed over a five-day period when animals received As/sub 2/O/sub 3/ at a dose of 1.7 to 2 mg (kg-d). These initial studies suggest that the minipump may be a useful means of studying the chronic effects of substances on cell proliferation in conjunction with the diffusion chamber assay system. A microscale synthesis of gold antirheumatoid agents was developed. This method involves reaction of thiohexose derivatives such as thioglucosetetraacetate (..beta..-D-TGTA) with trialkylphosphinegold halide intermediates (R/sub 3/PAu-Cl) in the presence of pyridine to give the coupling products R/sub 3/PAu(..beta..-D-TGTA) in good yield (>75%). Using this method, the triethyl analog Et/sub 3/PAu(..beta..-D-TGTA) and triphenyl analog (phi/sub 3/PAu(..beta..-D-TGTA)) have been prepared and characterized.This method will be used to prepare the /sup 195/Au-labeled agents. The platinum antitumor agent cis-dichloro-trans-dihydroxy-bis-(isopropylamine)-platinum (IV) (CHIP) has been purified. This system is efficient for separation of CHIP from impurities produced during the synthetic sequence and will be used to prepare /sup 195m/Pt-CHIP for biological evaluation. (ERB)« less

Secure and effective gene delivery system of plasmid DNA coated by polynucleotide.

PubMed

Kodama, Yukinobu; Ohkubo, Chikako; Kurosaki, Tomoaki; Egashira, Kanoko; Sato, Kayoko; Fumoto, Shintaro; Nishida, Koyo; Higuchi, Norihide; Kitahara, Takashi; Nakamura, Tadahiro; Sasaki, Hitoshi

2015-01-01

Polynucleotides are anionic macromolecules which are expected to transfer into the targeted cells through specific uptake mechanisms. So, we developed polynucleotides coating complexes of plasmid DNA (pDNA) and polyethylenimine (PEI) for a secure and efficient gene delivery system and evaluated their usefulness. Polyadenylic acid (polyA), polyuridylic acid (polyU), polycytidylic acid (polyC), and polyguanylic acid (polyG) were examined as the coating materials. pDNA/PEI/polyA, pDNA/PEI/polyU, and pDNA/PEI/polyC complexes formed nanoparticles with a negative surface charge although pDNA/PEI/polyG was aggregated. The pDNA/PEI/polyC complex showed high transgene efficiency in B16-F10 cells although there was little efficiency in pDNA/PEI/polyA and pDNA/PEI/polyU complexes. An inhibition study strongly indicated the specific uptake mechanism of pDNA/PEI/polyC complex. Polynucleotide coating complexes had lower cytotoxicity than pDNA/PEI complex. The pDNA/PEI/polyC complex showed high gene expression selectively in the spleen after intravenous injection into mice. The pDNA/PEI/polyC complex showed no agglutination with erythrocytes and no acute toxicity although these were observed in pDNA/PEI complex. Thus, we developed polynucleotide coating complexes as novel vectors for clinical gene therapy, and the pDNA/PEI/polyC complex as a useful candidate for a gene delivery system.

Fatty acid and sterol composition of three phytomonas species.

PubMed

Nakamura, C V; Waldow, L; Pelegrinello, S R; Ueda-Nakamura, T; Filho, B A; Filho, B P

1999-01-01

Fatty acid and sterol analysis were performed on Phytomonas serpens and Phytomonas sp. grown in chemically defined and complex medium, and P. françai cultivated in complex medium. The three species of the genus Phytomonas had qualitatively identical fatty acid patterns. Oleic, linoleic, and linolenic were the major unsaturated fatty acids. Miristic and stearic were the major saturated fatty acids. Ergosterol was the only sterol isolated from Phytmonas sp. and P. serpens grown in a sterol-free medium, indicating that it was synthesized de novo. When P. françai that does not grow in defined medium was cultivated in a complex medium, cholesterol was the only sterol detected. The fatty acids and sterol isolated from Phytomonas sp. and P. serpens grown in a chemically defined lipid-free medium indicated that they were able to biosynthesize fatty acids and ergosterol from acetate or from acetate precursors such as glucose or threonine.

Electrophoretic Mobility Shift Assay (EMSA) for Detecting Protein-Nucleic Acid Interactions

PubMed Central

Hellman, Lance M.; Fried, Michael G.

2009-01-01

The gel electrophoresis mobility shift assay (EMSA) is used to detect protein complexes with nucleic acids. It is the core technology underlying a wide range of qualitative and quantitative analyses for the characterization of interacting systems. In the classical assay, solutions of protein and nucleic acid are combined and the resulting mixtures are subjected to electrophoresis under native conditions through polyacrylamide or agarose gel. After electrophoresis, the distribution of species containing nucleic acid is determined, usually by autoradiography of 32P-labeled nucleic acid. In general, protein-nucleic acid complexes migrate more slowly than the corresponding free nucleic acid. In this article, we identify the most important factors that determine the stabilities and electrophoretic mobilities of complexes under assay conditions. A representative protocol is provided and commonly used variants are discussed. Expected outcomes are briefly described. References to extensions of the method and a troubleshooting guide are provided. PMID:17703195

Trapping by amylose of the aliphatic chain grafted onto chlorogenic acid: importance of the graft position.

PubMed

Le-Bail, P; Lorentz, C; Pencreac'h, G; Soultani-Vigneron, S; Pontoire, B; López Giraldo, L J; Villeneuve, P; Hendrickx, J; Tran, V

2015-03-06

5-Caffeoylquinic acid (chlorogenic acid), is classified in acid-phenols family and as polyphenolic compounds it possesses antioxidant activity. The oxydative modification of chlorogenic acid in foods may lead to alteration of their qualities; to counteract these degradation effects, molecular encapsulation was used to protect chlorogenic acid. Amylose can interact strongly with a number of small molecules, including lipids. In order to enable chlorogenic acid complexation by amylose, a C16 aliphatic chain was previously grafted onto the cycle of quinic acid. This work showed that for the two lipophilic derivatives of chlorogenic acid: hexadecyl chlorogenate obtained by alkylation and 3-O-palmitoyl chlorogenic acid obtained by acylation; only the 3-O-palmitoyl chlorogenic acid complexed amylose. The chlorogenic acid derivatives were studied by X-ray diffraction, differential scanning calorimetry and NMR to elucidate the interaction. By comparing the results with previous work on the complexation of amylose by 4-O-palmitoyl chlorogenic acid, the importance of the aliphatic chain position on the cycle of the quinic acid is clearly highlighted. A study in molecular modeling helped to understand the difference in behavior relative to amylose of these three derivatives of chlorogenic acid. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cytotoxicity of copper(II)-complexes with some S-alkyl derivatives of thiosalicylic acid. Crystal structure of the binuclear copper(II)-complex with S-ethyl derivative of thiosalicylic acid

NASA Astrophysics Data System (ADS)

Nikolić, Miloš V.; Mijajlović, Marina Ž.; Jevtić, Verica V.; Ratković, Zoran R.; Novaković, Slađana B.; Bogdanović, Goran A.; Milovanović, Jelena; Arsenijević, Aleksandar; Stojanović, Bojana; Trifunović, Srećko R.; Radić, Gordana P.

2016-07-01

The spectroscopically predicted structure of the obtained copper(II)-complex with S-ethyl derivative of thiosalicylic acid was confirmed by X-ray structural study and compared to previously reported crystal structure of the Cu complex with S-methyl derivative. Single crystals suitable for X-ray measurements were obtained by slow crystallization from a water solution. Cytotoxic effects of S-alkyl (R = benzyl (L1), methyl (L2), ethyl (L3), propyl (L4) and butyl (L5)) derivatives of thiosalicylic acid and the corresponding binuclear copper(II)-complexes on murine colon carcinoma cell lines, CT26 and CT26.CL25 and human colon carcinoma cell line HCT-116 were reported here. The analysis of cancer cell viability showed that all the tested complexes had low cytotoxic effect on murine colon carcinoma cell lines, but several times higher cytotoxicity on normal human colon carcinoma cells.

Occurrence of amylose-lipid complexes in teff and maize starch biphasic pastes.

PubMed

Wokadala, Obiro Cuthbert; Ray, Suprakas Sinha; Emmambux, Mohammad Naushad

2012-09-01

The occurrence of amylose-lipid complexes was determined in maize and teff starch biphasic pastes i.e. peak viscosity pastes at short and prolonged pasting times. Maize and teff starches were pasted for 11.5 and 130 min with or without added stearic acid followed by thermo-stable alpha-amylase hydrolysis in a rapid visco-analyzer. X-ray diffraction analysis of pastes before and residues after hydrolysis showed crystalline V-amylose diffraction patterns for the starches pasted for a prolonged time with added stearic acid while less distinct V-amylose patterns with non-complexed stearic acid peaks were observed with a short pasting time. Differential scanning calorimetry of pastes before and residues after paste hydrolysis showed that Type I amylose-lipid complexes were formed after pasting for the short duration with added stearic acid, while Type II complexes are formed after pasting for the prolonged time. The present research provides evidence that amylose-lipid complexes play an important role in starch biphasic pasting. Copyright © 2012 Elsevier Ltd. All rights reserved.

Syntheses, structures, photoluminescence of four dicarboxylate-controlled Zn(II) coordination complexes incorporating flexible 1-(4-pyridylmethyl)-benzimidazole ligand

NASA Astrophysics Data System (ADS)

Hao, Hong-Jun; Du, Ming-Yue; Wang, Dan-Feng; Sun, Cheng-Jie; Wang, Zhan-Hui; Huang, Rong-Bin; Zheng, Lan-Sun

2013-09-01

Four Zn(II) coordination complexes, namely {[Zn(pmbm)2(tpa)]·H2O}n (1), {[Zn(pmbm)(phda)]·2(H2O)}n (2), [Zn(pmbm)(aze)]n (3), {[Zn(pmbm)(1,4-ndc)]·2(CH3OH)}n (4) [pmbm = 1-(4-pyridylmethyl)-benzimidazole, H2tpa = terephthalic acid, H2phda = phenylenediacetic acid, H2aze = azelaic acid, 1,4-ndcH2 = 1,4-naphthalenedicarboxylic acid] have been synthesized by solution phase ultrasonic reactions of Zn(AC)2·2H2O with pmbm and various dicarboxylates ligands under the ammoniacal condition. All the complexes have been characterized by elemental analyses, IR spectra and X-ray diffraction. Complexes 1 and 2 exhibit one-dimensional chains structure and complex 3 and 4 are two-dimensional sheets structure with (4,4) topology. Complexes 1-4 spanning from one-dimensional chains to two-dimensional sheets suggest that dicarboxylates play significant roles in the formation of such coordination architectures. The photoluminescences of the complexes were also investigated in the solid state at room temperature.

Regulation of branched-chain amino acid catabolism in rat models for spontaneous type 2 diabetes mellitus.

PubMed

Kuzuya, Teiji; Katano, Yoshiaki; Nakano, Isao; Hirooka, Yoshiki; Itoh, Akihiro; Ishigami, Masatoshi; Hayashi, Kazuhiko; Honda, Takashi; Goto, Hidemi; Fujita, Yuko; Shikano, Rie; Muramatsu, Yuji; Bajotto, Gustavo; Tamura, Tomohiro; Tamura, Noriko; Shimomura, Yoshiharu

2008-08-15

The branched-chain alpha-keto acid dehydrogenase (BCKDH) complex is the most important regulatory enzyme in branched-chain amino acid (BCAA) catabolism. We examined the regulation of hepatic BCKDH complex activity in spontaneous type 2 diabetes Otsuka Long-Evans Tokushima Fatty (OLETF) rats and Zucker diabetic fatty rats. Hepatic BCKDH complex activity in these rats was significantly lower than in corresponding control rats. The amount of BCKDH complex in OLETF rats corresponded to the total activity of the complex. Activity and abundance of the bound form of BCKDH kinase, which is responsible for inactivation of the complex, showed an inverse correlation to BCKDH complex activity in OLETF rats. Dietary supplementation of 5% BCAAs for 10 weeks markedly increased BCKDH complex activity, and decreased the activity and bound form of BCKDH kinase in the rats. These results suggest that BCAA catabolism in type 2 diabetes is downregulated and enhanced by BCAA supplementation.

Chronic exposure to emissions from photocopiers in copy shops causes oxidative stress and systematic inflammation among photocopier operators in India.

PubMed

Elango, Nithya; Kasi, Vallikkannu; Vembhu, Bhuvaneswari; Poornima, Jeyanthi Govindasamy

2013-09-11

We assessed indoor air quality in photocopier centers and investigated whether occupational exposure to emissions from photocopiers is associated with decline in lung function or changes in haematological parameters, oxidative stress and inflammatory status. Indoor air quality was monitored in five photocopier centers. Pulmonary function was assessed by spirometry in 81 photocopier operators (64 male and 17 female) and 43 healthy control (31 male and 12 female) subjects. Hematological status, serum thio-barbituric acid reactive substances (TBARS), total ferric reducing antioxidant capacity (FRAC), leukotriene B4 (LTB4), 8-isoprostane, C reactive protein (CRP), interleukin 8 (IL-8), clara cell protein (CC-16), intercellular adhesion molecule 1 (ICAM-1) and eosinophilic cationic protein (ECP) were analyzed. Relationships between cumulative exposure, lung function and inflammatory markers were assessed. PM10 and PM2.5 were above the permissible levels in all the photocopier centers, whereas the levels of carbon monoxide, nitrogen oxides, ozone, sulphur dioxide, lead, arsenic, nickel, ammonia, benzene and benzo(a)pyrene were within Indian ambient air quality standards. Lung function was similar in the photocopier operators and control subjects. Serum TBARS was significantly higher and FRAC was lower among photocopier operators when compared to healthy controls. Plasma IL-8, LTB4, ICAM-1 and ECP were significantly higher in the photocopier exposed group. Photocopiers emit high levels of particulate matter. Long term exposure to emissions from photocopiers was not associated with decreased lung function, but resulted in high oxidative stress and systemic inflammation leading to high risk of cardiovascular diseases.

Chronic exposure to emissions from photocopiers in copy shops causes oxidative stress and systematic inflammation among photocopier operators in India

PubMed Central

2013-01-01

Background We assessed indoor air quality in photocopier centers and investigated whether occupational exposure to emissions from photocopiers is associated with decline in lung function or changes in haematological parameters, oxidative stress and inflammatory status. Methods Indoor air quality was monitored in five photocopier centers. Pulmonary function was assessed by spirometry in 81 photocopier operators (64 male and 17 female) and 43 healthy control (31 male and 12 female) subjects. Hematological status, serum thio-barbituric acid reactive substances (TBARS), total ferric reducing antioxidant capacity (FRAC), leukotriene B4 (LTB4), 8-isoprostane, C reactive protein (CRP), interleukin 8 (IL-8), clara cell protein (CC-16), intercellular adhesion molecule 1 (ICAM-1) and eosinophilic cationic protein (ECP) were analyzed. Relationships between cumulative exposure, lung function and inflammatory markers were assessed. Results PM10 and PM2.5 were above the permissible levels in all the photocopier centers, whereas the levels of carbon monoxide, nitrogen oxides, ozone, sulphur dioxide, lead, arsenic, nickel, ammonia, benzene and benzo(a)pyrene were within Indian ambient air quality standards. Lung function was similar in the photocopier operators and control subjects. Serum TBARS was significantly higher and FRAC was lower among photocopier operators when compared to healthy controls. Plasma IL-8, LTB4, ICAM-1 and ECP were significantly higher in the photocopier exposed group. Conclusions Photocopiers emit high levels of particulate matter. Long term exposure to emissions from photocopiers was not associated with decreased lung function, but resulted in high oxidative stress and systemic inflammation leading to high risk of cardiovascular diseases. PMID:24025094

Sniffer patch laser uncaging response (SPLURgE): an assay of regional differences in allosteric receptor modulation and neurotransmitter clearance

PubMed Central

Christian, Catherine A.

2013-01-01

Allosteric modulators exert actions on neurotransmitter receptors by positively or negatively altering the effective response of these receptors to their respective neurotransmitter. γ-Aminobutyric acid (GABA) type A ionotropic receptors (GABAARs) are major targets for allosteric modulators such as benzodiazepines, neurosteroids, and barbiturates. Analysis of substances that produce similar effects has been hampered by the lack of techniques to assess the localization and function of such agents in brain slices. Here we describe measurement of the sniffer patch laser uncaging response (SPLURgE), which combines the sniffer patch recording configuration with laser photolysis of caged GABA. This methodology enables the detection of allosteric GABAAR modulators endogenously present in discrete areas of the brain slice and allows for the application of exogenous GABA with spatiotemporal control without altering the release and localization of endogenous modulators within the slice. Here we demonstrate the development and use of this technique for the measurement of allosteric modulation in different areas of the thalamus. Application of this technique will be useful in determining whether a lack of modulatory effect on a particular category of neurons or receptors is due to insensitivity to allosteric modulation or a lack of local release of endogenous ligand. We also demonstrate that this technique can be used to investigate GABA diffusion and uptake. This method thus provides a biosensor assay for rapid detection of endogenous GABAAR modulators and has the potential to aid studies of allosteric modulators that exert effects on other classes of neurotransmitter receptors, such as glutamate, acetylcholine, or glycine receptors. PMID:23843428

Sniffer patch laser uncaging response (SPLURgE): an assay of regional differences in allosteric receptor modulation and neurotransmitter clearance.

PubMed

Christian, Catherine A; Huguenard, John R

2013-10-01

Allosteric modulators exert actions on neurotransmitter receptors by positively or negatively altering the effective response of these receptors to their respective neurotransmitter. γ-Aminobutyric acid (GABA) type A ionotropic receptors (GABAARs) are major targets for allosteric modulators such as benzodiazepines, neurosteroids, and barbiturates. Analysis of substances that produce similar effects has been hampered by the lack of techniques to assess the localization and function of such agents in brain slices. Here we describe measurement of the sniffer patch laser uncaging response (SPLURgE), which combines the sniffer patch recording configuration with laser photolysis of caged GABA. This methodology enables the detection of allosteric GABAAR modulators endogenously present in discrete areas of the brain slice and allows for the application of exogenous GABA with spatiotemporal control without altering the release and localization of endogenous modulators within the slice. Here we demonstrate the development and use of this technique for the measurement of allosteric modulation in different areas of the thalamus. Application of this technique will be useful in determining whether a lack of modulatory effect on a particular category of neurons or receptors is due to insensitivity to allosteric modulation or a lack of local release of endogenous ligand. We also demonstrate that this technique can be used to investigate GABA diffusion and uptake. This method thus provides a biosensor assay for rapid detection of endogenous GABAAR modulators and has the potential to aid studies of allosteric modulators that exert effects on other classes of neurotransmitter receptors, such as glutamate, acetylcholine, or glycine receptors.

The role of training dose in drug discrimination: a review

PubMed Central

Stolerman, Ian P; Childs, Emma; Ford, Matthew M; Grant, Kathleen A

2011-01-01

Drug discrimination has been an important technique in behavioural pharmacology for at least 40 years. The characteristics of drug-produced discriminative stimuli are influenced by behavioural and pharmacological variables, including the doses used to establish discriminations. This review covers studies on the effects of varying the training dose of a drug in a search for general principles that are applicable across different drug classes and methodological approaches. With respect to quantitative changes, relationships between training dose and rate of acquisition or magnitude of stimulus control were found for most drug classes. Acquisition accelerated with dose up to a point beyond which drug-induced impairments of performance had a deleterious impact. Sensitivity to the training drug as measured by ED50 values typically increased when the training dose was reduced. Qualitative changes were more complex and appeared to fall into three categories: (i) changes in profiles of generalisation between partial and full agonists; (ii) reduced specificity of some discriminations at small training doses and (iii) changes in the relative salience of actions mediated through different neurotransmitter systems or from central and peripheral sites. Three-lever discrimination procedures incorporating ‘drug versus drug’ or “dose versus dose” contingencies enabled detection of more subtle differences than the simple ‘drug versus no drug’ approach when applied to the opioid, hallucinogen and barbiturate classes of drugs. These conclusions have implications for the interpretation of data from studies that utilise either within- or between-subject designs for studying the discriminative stimulus effects of drugs. PMID:21808191

Molecular mechanisms of the cytotoxicity of human α-lactalbumin made lethal to tumor cells (HAMLET) and other protein-oleic acid complexes.

PubMed

Nakamura, Takashi; Aizawa, Tomoyasu; Kariya, Ryusho; Okada, Seiji; Demura, Makoto; Kawano, Keiichi; Makabe, Koki; Kuwajima, Kunihiro

2013-05-17

Although HAMLET (human α-lactalbumin made lethal to tumor cells), a complex formed by human α-lactalbumin and oleic acid, has a unique apoptotic activity for the selective killing of tumor cells, the molecular mechanisms of expression of the HAMLET activity are not well understood. Therefore, we studied the molecular properties of HAMLET and its goat counterpart, GAMLET (goat α-lactalbumin made lethal to tumor cells), by pulse field gradient NMR and 920-MHz two-dimensional NMR techniques. We also examined the expression of HAMLET-like activities of complexes between oleic acid and other proteins that form a stable molten globule state. We observed that both HAMLET and GAMLET at pH 7.5 were heterogeneous, composed of the native protein, the monomeric molten globule-like state, and the oligomeric species. At pH 2.0 and 50 °C, HAMLET and GAMLET appeared in the monomeric state, and we identified the oleic acid-binding site in the complexes by two-dimensional NMR. Rather surprisingly, the binding site thus identified was markedly different between HAMLET and GAMLET. Furthermore, canine milk lysozyme, apo-myoglobin, and β2-microglobulin all formed the HAMLET-like complex with the anti-tumor activity, when the protein was treated with oleic acid under conditions in which their molten globule states were stable. From these results, we conclude that the protein portion of HAMLET, GAMLET, and the other HAMLET-like protein-oleic acid complexes is not the origin of their cytotoxicity to tumor cells and that the protein portion of these complexes plays a role in the delivery of cytotoxic oleic acid molecules into tumor cells across the cell membrane.

Molecular Mechanisms of the Cytotoxicity of Human α-Lactalbumin Made Lethal to Tumor Cells (HAMLET) and Other Protein-Oleic Acid Complexes*

PubMed Central

Nakamura, Takashi; Aizawa, Tomoyasu; Kariya, Ryusho; Okada, Seiji; Demura, Makoto; Kawano, Keiichi; Makabe, Koki; Kuwajima, Kunihiro

2013-01-01

Although HAMLET (human α-lactalbumin made lethal to tumor cells), a complex formed by human α-lactalbumin and oleic acid, has a unique apoptotic activity for the selective killing of tumor cells, the molecular mechanisms of expression of the HAMLET activity are not well understood. Therefore, we studied the molecular properties of HAMLET and its goat counterpart, GAMLET (goat α-lactalbumin made lethal to tumor cells), by pulse field gradient NMR and 920-MHz two-dimensional NMR techniques. We also examined the expression of HAMLET-like activities of complexes between oleic acid and other proteins that form a stable molten globule state. We observed that both HAMLET and GAMLET at pH 7.5 were heterogeneous, composed of the native protein, the monomeric molten globule-like state, and the oligomeric species. At pH 2.0 and 50 °C, HAMLET and GAMLET appeared in the monomeric state, and we identified the oleic acid-binding site in the complexes by two-dimensional NMR. Rather surprisingly, the binding site thus identified was markedly different between HAMLET and GAMLET. Furthermore, canine milk lysozyme, apo-myoglobin, and β2-microglobulin all formed the HAMLET-like complex with the anti-tumor activity, when the protein was treated with oleic acid under conditions in which their molten globule states were stable. From these results, we conclude that the protein portion of HAMLET, GAMLET, and the other HAMLET-like protein-oleic acid complexes is not the origin of their cytotoxicity to tumor cells and that the protein portion of these complexes plays a role in the delivery of cytotoxic oleic acid molecules into tumor cells across the cell membrane. PMID:23580643

Competition of hydrogen bonds and halogen bonds in complexes of hypohalous acids with nitrogenated bases.

PubMed

Alkorta, Ibon; Blanco, Fernando; Solimannejad, Mohammad; Elguero, Jose

2008-10-30

A theoretical study of the complexes formed by hypohalous acids (HOX, X = F, Cl, Br, I, and At) with three nitrogenated bases (NH 3, N 2, and NCH) has been carried out by means of ab initio methods, up to MP2/aug-cc-pVTZ computational method. In general, two minima complexes are found, one with an OH...N hydrogen bond and the other one with a X...N halogen bond. While the first one is more stable for the smallest halogen derivatives, the two complexes present similar stabilities for the iodine case and the halogen-bonded structure is the most stable one for the hypoastatous acid complexes.

NMR assignment of a PDZ domain in complex with a HPV51 E6 derived N-terminally pyroglutamic acid modified peptide.

PubMed

Mischo, André; Ohlenschläger, Oliver; Ramachandran, Ramadurai; Görlach, Matthias

2013-04-01

The resonance assignment of an amino-terminal pyroglutamic acid containing peptide derived from the E6 protein of human papillomavirus (HPV) type 51 in complex with PDZ domain 2 of hDlg/SAP-97 is reported. The assignments include (1)H, (13)C and (15)N resonances for the protein and peptide in the complex and all of the peptide's pyroglutamic acid nuclei.

Use of an exchange method to estimate the association and dissociation rate constants of cadmium complexes formed with low-molecular-weight organic acids commonly exuded by plant roots.

PubMed

Schneider, André; Nguyen, Christophe

2011-01-01

Organic acids released from plant roots can form complexes with cadmium (Cd) in the soil solution and influence metal bioavailability not only due to the nature and concentration of the complexes but also due to their lability. The lability of a complex influences its ability to buffer changes in the concentration of free ions (Cd); it depends on the association (, m mol s) and dissociation (, s) rate constants. A resin exchange method was used to estimate and (m mol s), which is the conditional estimate of depending on the calcium (Ca) concentration in solution. The constants were estimated for oxalate, citrate, and malate, three low-molecular-weight organic acids commonly exuded by plant roots and expected to strongly influence Cd uptake by plants. For all three organic acids, the and estimates were around 2.5 10 m mol s and 1.3 × 10 s, respectively. Based on the literature, these values indicate that the Cd- low-molecular-weight organic acids complexes formed between Cd and low-molecular-weight organic acids may be less labile than complexes formed with soil soluble organic matter but more labile than those formed with aminopolycarboxylic chelates. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Starch-lipid inclusion complexes for aerogel formation

USDA-ARS?s Scientific Manuscript database

Recently we reported that aqueous slurries of starch can be excess steam jet-cooked and blended with aqueous solutions of fatty acid salts to produce inclusion complexes between amylose and the fatty acid salt. These complexes can be simply prepared on large scale using commercially available steam ...

Membrane protein complexes catalyze both 4- and 3-hydroxylation of cinnamic acid derivatives in monolignol biosynthesis

PubMed Central

Chen, Hsi-Chuan; Li, Quanzi; Shuford, Christopher M.; Liu, Jie; Muddiman, David C.; Sederoff, Ronald R.; Chiang, Vincent L.

2011-01-01

The hydroxylation of 4- and 3-ring carbons of cinnamic acid derivatives during monolignol biosynthesis are key steps that determine the structure and properties of lignin. Individual enzymes have been thought to catalyze these reactions. In stem differentiating xylem (SDX) of Populus trichocarpa, two cinnamic acid 4-hydroxylases (PtrC4H1 and PtrC4H2) and a p-coumaroyl ester 3-hydroxylase (PtrC3H3) are the enzymes involved in these reactions. Here we present evidence that these hydroxylases interact, forming heterodimeric (PtrC4H1/C4H2, PtrC4H1/C3H3, and PtrC4H2/C3H3) and heterotrimeric (PtrC4H1/C4H2/C3H3) membrane protein complexes. Enzyme kinetics using yeast recombinant proteins demonstrated that the enzymatic efficiency (Vmax/km) for any of the complexes is 70–6,500 times greater than that of the individual proteins. The highest increase in efficiency was found for the PtrC4H1/C4H2/C3H3-mediated p-coumaroyl ester 3-hydroxylation. Affinity purification-quantitative mass spectrometry, bimolecular fluorescence complementation, chemical cross-linking, and reciprocal coimmunoprecipitation provide further evidence for these multiprotein complexes. The activities of the recombinant and SDX plant proteins demonstrate two protein-complex–mediated 3-hydroxylation paths in monolignol biosynthesis in P. trichocarpa SDX; one converts p-coumaric acid to caffeic acid and the other converts p-coumaroyl shikimic acid to caffeoyl shikimic acid. Cinnamic acid 4-hydroxylation is also mediated by the same protein complexes. These results provide direct evidence for functional involvement of membrane protein complexes in monolignol biosynthesis. PMID:22160716

Voltammetric study of the boric acid-salicylaldehyde-H-acid ternary system and its application to the voltammetric determination of boron.

PubMed

Kajiwara, Mari; Ito, Yoshio N; Miyazaki, Yoshinobu; Fujimori, Takao; Takehara, Kô; Yoshimura, Kazuhisa

2015-02-14

The ternary system of boric acid, salicylaldehyde (SA) and H-acid (HA) was voltammetrically studied from kinetic and equilibrium points of view. The effect of the SA substituents was also studied by using two analogs, 5-fluorosalicylaldehyde (F-SA) and 5-methylsalicylaldehyde (Me-SA). The three cathodic peaks of Azomethine H (AzH), Azomethine H-boric acid complex (AzB), and free SA were observed in the solution containing boric acid, SA and HA. The peak potentials of AzH and SA were shifted to negative potentials with increasing pH, while the peak potential of AzB was pH-independent. This difference indicates that a proton participates in the charge-transfer steps of the AzH and SA reductions, but not in that of the AzB reduction. The formation constants for the AzB complexation were similar among all the examined analogs. In the kinetic study, the reaction rate was higher in an acidic condition for the AzH formation, but in a neutral condition for the AzB formation. The rate constants for the AzB complexes were in the order of F-SA > SA ≈ Me-SA, indicating that the fluoro group accelerates the F-AzB complexation. The AzB complexation mechanism is considered to consist of more than three steps, i.e., the pre-equilibrium of the salicylaldehyde-boric acid complex (SA-B) formation, the nucleophilic attack of HA on SA-B, and the remaining some steps to form AzB. Based on these results, the voltammetric determination method of boron using F-SA was optimized, which allowed the boron concentration to be determined within only 5 min with a 0.03 mg B dm(-3) detection limit.

Wormlike micelle formation by acylglutamic acid with alkylamines.

PubMed

Sakai, Kenichi; Nomura, Kazuyuki; Shrestha, Rekha Goswami; Endo, Takeshi; Sakamoto, Kazutami; Sakai, Hideki; Abe, Masahiko

2012-12-21

Rheological properties of alkyl dicarboxylic acid-alkylamine complex systems have been characterized. The complex materials employed in this study consist of an amino acid-based surfactant (dodecanoylglutamic acid, C12Glu) and a tertiary alkylamine (dodecyldimethylamine, C12DMA) or a secondary alkylamine (dodecylmethylamine, C12MA). (1)H NMR and mass spectroscopic data have suggested that C12Glu forms a stoichiometric 1:1 complex with C12DMA and C12MA. Rheological measurements have suggested that the complex systems yield viscoelastic wormlike micellar solutions and the rheological behavior is strongly dependent on the aqueous solution pH. This pH-dependent behavior results from the structural transformation of the wormlike micelles to occur in the narrow pH range 5.5-6.2 (in the case of C12Glu-C12DMA system); i.e., positive curved aggregates such as spherical or rodlike micelles tend to be formed at high pH values. Our current study offers a unique way to obtain viscoelastic wormlike micellar solutions by means of alkyl dicarboxylic acid-alkylamine complex as gemini-like amphiphiles.

Database of amino acid-nucleotide contacts in contacts in DNA-homeodomain protein

NASA Astrophysics Data System (ADS)

Grokhlina, T. I.; Zrelov, P. V.; Ivanov, V. V.; Polozov, R. V.; Chirgadze, Yu. N.; Sivozhelezov, V. S.

2013-09-01

The analysis of amino acid-nucleotide contacts in interfaces of the protein-DNA complexes, intended to find consistencies in the protein-DNA recognition, is a complex problem that requires an analysis of the physicochemical characteristics of these contacts and the positions of the participating amino acids and nucleotides in the chains of the protein and the DNA, respectively, as well as conservatism of these contacts. Thus, those heterogeneous data should be systematized. For this purpose we have developed a database of amino acid-nucleotide contacts ANTPC (Amino acid Nucleotide Type Position Conservation) following the archetypal example of the proteins in the homeodomain family. We show that it can be used to compare and classify the interfaces of the protein-DNA complexes.

Mammalian gravity receptors: Structure and metabolism

NASA Technical Reports Server (NTRS)

Ross, M.

1984-01-01

High performance liquid chromatography (HPLC) instrumentation was used for amino acid analysis of rat otoconial complexes. The amino acids of otoconial complexes pooled by origin from only 10 rats were analyzed. It is indicated that it should be possible to analyze complexes from only three rats, and perhaps fewer, which means that the method should be applicable to material from space flow rats. It is suggested that the organic otoconial phase is comparable in its complement of acidic amino acids to other calcium carbonate containing materials such as fish otoliths and certain mollusk shells. The organic material is high in acidic amino acids; and the relative proportions of aspirate, glutamate, threonine and serine appear to be similar to those found in neogastropod shells. Its significance to the evolution of biomineralization processes occurring in the animal kingdom is emphasized.

Luminescence Studies of the Ligand Exchange Between Two Phenanthroline Complexes and Bovine Serum Albumin

NASA Astrophysics Data System (ADS)

Lin, H.-B.; Shen, Q.-H.

2017-03-01

The interactions between bovine serum albumin (BSA) and two Cu(II) phenanthroline complexes were studied by fluorescence and UV-visible absorption spectroscopy. The obtained results confirm that the phen ligand (phen = 1,10-phenanthroline) is dissociated from the two complexes and moves into the hydrophobic cavity of BSA and that the M-L complexes (M = Co2+, Cu2+; L = Hlact, imda; Hlact = lactic acid, H2imda = iminodiacetic acid) coordinate with the amino acids on the surface of the peptide in the solution. This mode of action significantly inhibits the denaturation of BSA. The calculated distance between the BSA and the two complexes suggests that the energy transfer from the excited state of BSA to a complex occurs with high efficiency.

Formation of inclusion complexes between high amylose starch and octadecyl ferulate via steam jet cooking

USDA-ARS?s Scientific Manuscript database

Amylose can form inclusion complexes with guest molecules and represents an interesting approach to deliver bioactive molecules. However, ferulic acid has been shown not to form single helical inclusion complexes with amylose. To overcome this problem a ferulic acid ester, octadecyl ferulate, posses...

High temperature dissolution of oxides in complexing media

NASA Astrophysics Data System (ADS)

Sathyaseelan, Valil S.; Rufus, Appadurai L.; Subramanian, Hariharan; Bhaskarapillai, Anupkumar; Wilson, Shiny; Narasimhan, Sevilimedu V.; Velmurugan, Sankaralingam

2011-12-01

Dissolution of transition metal oxides such as magnetite (Fe 3O 4), mixed ferrites (NiFe 2O 4, ZnFe 2O 4, MgFe 2O 4), bonaccordite (Ni 2FeBO 5) and chromium oxide (Cr 2O 3) in organic complexing media was attempted at higher temperatures (80-180 °C). On increasing the temperature from 80 to 180 °C, the dissolution rate of magnetite in nitrilo triacetic acid (NTA) medium increased six folds. The trend obtained for the dissolution of other oxides was ZnFe 2O 4 > NiFe 2O 4 > MgFe 2O 4 > Cr 2O 3, which followed the same trend as the lability of their metal-oxo bonds. Other complexing agents such as ethylene diamine tetra acetic acid (EDTA), pyridine dicarboxylic acid (PDCA), citric acid and reducing agents viz., oxalic acid and ascorbic acid were also evaluated for their oxide dissolution efficiency at 160 °C. EDTA showed maximum dissolution rate of 21.4 μm/h for magnetite. Addition of oxalic acid/ascorbic acid to complexing media (NTA/EDTA) showed identical effect on the dissolution of magnetite. Addition of hydrazine, another reducing agent, to NTA decreased the rate of dissolution of magnetite by 50%.

Leaching behavior and chemical stability of copper butyl xanthate complex under acidic conditions.

PubMed

Chang, Yi Kuo; Chang, Juu En; Chiang, Li Choung

2003-08-01

Although xanthate addition can be used for treating copper-containing wastewater, a better understanding of the leaching toxicity and the stability characteristics of the copper xanthate complexes formed is essential. This work was undertaken to evaluate the leaching behavior of copper xanthate complex precipitates by means of toxicity characteristics leaching procedure (TCLP) and semi-dynamic leaching test (SDLT) using 1 N acetic acid solution as the leachant. Also, the chemical stability of the copper xanthate complex during extraction has been examined with the studying of variation of chemical structure using UV-vis, Fourier transform infrared and X-ray photoelectron spectroscopies (XPS). Both TCLP and SDLT results showed that a negligible amount of copper ion was leached out from the copper xanthate complex precipitate, indicating that the complex exhibited a high degree of copper leaching stability under acidic conditions. Nevertheless, chemical structure of the copper xanthate complex precipitate varied during the leaching tests. XPS data suggested that the copper xanthate complex initially contained both cupric and cuprous xanthate, but the unstable cupric xanthate change to the cuprous form after acid extraction, indicating the cuprous xanthate to be the final stabilizing structure. Despite that, the changes of chemical structure did not induce the rapid leaching of copper from the copper xanthate complex.

Solid-state supramolecular architectures formed by co-crystallization of melamine and 2-, 3- and 4-fluorophenylacetic acids

NASA Astrophysics Data System (ADS)

Perpétuo, Genivaldo Julio; Janczak, Jan

2018-01-01

A family of supramolecular complexes of melamine with fluorophenylacetic acid isomers using solvent-assisted and evaporation-based techniques has been prepared. Crystallization of melamine with 2-fluorophenylacetic acid yield hydrated ionic supramolecular complex (1), whereas crystallization of melamine with 3- and 4-fluorophenylacetic acids leads to formation of neutral supramolecular complexes (2, 3), all with base to acid ratio of 1:2. The supramolecular assembly is driven by the noncovalent interactions, most commonly by the hydrogen bonds. The components of the crystal 1 interact via Nsbnd H⋯O and Osbnd H⋯N hydrogen bonds with R22(8) and R32(10) graphs forming ionic supramolecular complex, whereas the components in the crystals 2 and 3 interact with a graph of R22(8) forming neutral supramolecular complexes. The singly protonated melamin-1-ium residues in 1 interact each other via a pair of Nsbnd H⋯N hydrogen bonds forming one dimensional chains along [-110] that interact via Nsbnd H⋯O with deprotonated and neutral 2-fluorophenylacetic acid units and water molecules forming ribbon. In 2 and 3 co-crystals the melamine interacts with 3- and 4-fluorophenylacetic acids via a pair of Nsbnd H⋯O hydrogen bonds forming pseudo one-dimensional supramolecular chains along [010] direction. Hirshfeld surface and analysis of 2D fingerprint plots have been analysed both quantitatively and qualitatively interactions that governing the supramolecular organisation. The IR and Raman vibrational characterization of the supramolecular complexes 1-3 was supported by the spectra of their deuterated analogues.

Synthesis, structure elucidation, biological screening, molecular modeling and DNA binding of some Cu(II) chelates incorporating imines derived from amino acids

NASA Astrophysics Data System (ADS)

Abdel-Rahman, Laila H.; Abu-Dief, Ahmed M.; Ismael, Mohammed; Mohamed, Mounir A. A.; Hashem, Nahla Ali

2016-01-01

Three tridentate Schiff bases amino acids were prepared by direct condensation of 3-methoxysalicylaldehyde (MS) or 4-diethylaminosalicylaldehyde (DS) with α-amino acid ligands [L-phenylalanine (P), L-histidine (H) and DL-tryptophan (T)]. The prepared Schiff bases amino acids were investigated by melting points, elemental analysis, 1HNMR and 13CNMR, IR, UV-Vis spectra, conductivity and magnetic measurements analyses. Subsequently, copper was introduced and Cu(II) complexes formed. These complexes were analyzed by thermal and elemental analyses and further investigated by FT-IR and UV/Vis spectroscopies. The experimental results indicating that all Cu(II) complexes contain hydrated water molecules (except DSPCu complex) and don't contain coordinated water molecules. The kinetic and thermal parameters were extracted from the thermal data using Coast and Redfern method. The molar conductance values of the Schiff base amino acid ligands and their Cu(II) complexes were relatively low, showing that these compounds have non-electrolytic nature. Magnetic susceptibility measurements showed the diamagnetic nature of the Schiff base amino acid ligands and paramagnetic nature of their complexes. Additionally, a spectrophotometric method was determined to extract their stability constants. It was found that the complexes possess 1:2 (M:L) stoichiometry. The results suggested that 3-methoxysalicylaldehyde and 4-diethylaminosalicylaldehyde amino acid Schiff bases behave as monobasic tridentate ONO ligands and coordinate Cu(II) ions in octahedral geometry according to the general formula [Cu(HL)2]·nH2O. To further understanding the structural and electronic properties of these complexes, Density Functional Theory (DFT) calculations were employed and provided a satisfactory description. The optimized structures of MST Schiff base ligand and its complex were calculated using DFT. The antimicrobial activity of the Schiff base ligands and their complexes were screened against some types of bacteria such as Bacillus subtilis (+ve), Escherichia coli (-ve) and Micrococcus luteus (+ve) and some types of fungi such as Asperagillus niger, Candida glabrata and Saccharomyces cerevisiae. The results of these studies indicated that the metal complexes exhibit a stronger antibacterial and antifungal efficiency compared to their corresponding ligands. The complexes were screened for antiviral activity against a panel of DNA and RNA viruses. Minimum cytotoxic and minimum virus inhibitory concentrations of these complexes were determined. The mode of interaction between complexes and CT-DNA was monitored using absorption spectra, viscosity measurements and gel electrophoreses.

Lipoic acid metabolism and mitochondrial redox regulation.

PubMed

Solmonson, Ashley D; DeBerardinis, Ralph J

2017-11-30

Lipoic acid is an essential cofactor for mitochondrial metabolism and is synthesized de novo using intermediates from mitochondrial fatty acid synthesis type II, S-adenosylmethionine and iron-sulfur clusters. This cofactor is required for catalysis by multiple mitochondrial 2-ketoacid dehydrogenase complexes, including pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase, and branched-chain ketoacid dehydrogenase. Lipoic acid also plays a critical role in stabilizing and regulating these multi-enzyme complexes.  Many of these dehydrogenases are regulated by reactive oxygen species, mediated through the disulfide bond of the prosthetic lipoyl moiety.  Collectively, its functions explain why lipoic acid is required for cell growth, mitochondrial activity and coordination of fuel metabolism. Lipoic acid is an essential cofactor for mitochondrial metabolism and is synthesized de novo using intermediates from mitochondrial fatty acid synthesis type II, S-adenosylmethionine and iron-sulfur clusters. This cofactor is required for catalysis by multiple mitochondrial 2-ketoacid dehydrogenase complexes, including pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase, and branched-chain ketoacid dehydrogenase. Lipoic acid also plays a critical role in stabilizing and regulating these multi-enzyme complexes.  Many of these dehydrogenases are regulated by reactive oxygen species, mediated through the disulfide bond of the prosthetic lipoyl moiety.  Collectively, its functions explain why lipoic acid is required for cell growth, mitochondrial activity and coordination of fuel metabolism. Copyright © 2017, The American Society for Biochemistry and Molecular Biology.

Regulation of hepatic branched-chain alpha-keto acid dehydrogenase complex in rats fed a high-fat diet

USDA-ARS?s Scientific Manuscript database

Objective: Branched-chain alpha-keto acid dehydrogenase complex (BCKDC) regulates branched-chain amino acid (BCAA) metabolism at the level of branched chain alpha-ketoacid (BCKA) catabolism. It has been demonstrated that the activity of hepatic BCKDC is markedly decreased in type 2 diabetic animal...

Thermometric titration of beta-aryl-alpha-mercaptopropenoic acids and determination of the stoichiometry of their metal complexes.

PubMed

Izquierdo, A; Carrasco, J

1981-05-01

Automatic thermometric titration was applied to some beta-aryl-alpha-mercaptopropenoic acids and the stoichiometry of their complexes with several metal ions was investigated. The heats of neutralization of the mercapto-acids with sodium hydroxide and the heats of their reaction with metal ions were calculated.

Properties of extruded starch-poly(methyl acrylate) graft copolymers prepared from spherulites formed from amylose-oleic acid inclusion complexes

USDA-ARS?s Scientific Manuscript database

Mixtures of high amylose corn starch and oleic acid were processed by steam jet-cooking, and the dispersions were rapidly cooled to yield amylose-oleic acid inclusion complexes as sub-micron spherulites and spherulite aggregates. Dispersions of these spherulite particles were then graft polymerized ...

Nanoparticle-enhanced fluorescence emission for non-separation assays of carbohydrates using a boronic acid-alizarin complex.

PubMed

Li, Qianjin; Kamra, Tripta; Ye, Lei

2016-03-04

Addition of crosslinked polymer nanoparticles into a solution of a 3-nitrophenylboronic acid-alizarin complex leads to significant enhancement of fluorescence emission. Using the nanoparticle-enhanced boronic acid-alizarin system has improved greatly the sensitivity and extended the dynamic range of separation-free fluorescence assays for carbohydrates.

Synthesis and luminescent properties of the novel poly(ethylene-co-acrylic acid) films based on surface modification with lanthanide (Eu3+, Tb3+) complexes

NASA Astrophysics Data System (ADS)

Wu, Yuewen; Chu, Yang; Yu, Zhenjiang; Hao, Haixia; Wu, Qingyao; Xie, Hongde

2017-10-01

Two kinds of novel fluorescent films have been successfully synthesized by surface modification on the poly(ethylene-co-acrylic acid) films using the lanthanide (Eu3+, Tb3+) complexes. The process consists of three steps: conversion of carboxylic acid groups on the surface of the poly(ethylene-co-acrylic acid) films to acid chloride groups, synthesis of the lanthanide complexes bearing amino groups, and amidation to form the modified films. To characterize the modified films, Fourier transform infrared, thermogravimetric analysis, static water contact angle measurements and photoluminescence tests have been employed. Fourier transform infrared verifies the successful preparation of the lanthanide complexes and the modified poly(ethylene-co-acrylic acid) films. These films can emit strong characteristic red and green light under UV light excitation. In addition, the films both have short lifetime (1.14 ms and 1.21 ms), high thermal stability (Td = 408 °C and 411 °C) and, compared with unmodified ones, increased hydrophilicity. All these results suggest that the modified films have potential application as luminescent materials under high temperature.

A combined experimental and DFT study of active structures and self-cycle mechanisms of mononuclear tungsten peroxo complexes in oxidation reactions

NASA Astrophysics Data System (ADS)

Jin, Peng; Wei, Donghui; Wen, Yiqiang; Luo, Mengfei; Wang, Xiangyu; Tang, Mingsheng

2011-04-01

Tungsten peroxo complexes have been widely used in olefin epoxidation, alcohol oxidation, Baeyer-Villiger oxidation and other oxidation reactions, however, there is still not a unanimous viewpoint for the active structure of mononuclear tungsten peroxo complex by now. In this paper, the catalysis of mononuclear tungsten peroxo complexes 0- 5 with or without acidic ligands for the green oxidation of cyclohexene to adipic acid in the absence of organic solvent and phase-transfer catalyst has been researched in experiment. Then we have suggested two possible kinds of active structures of mononuclear tungsten peroxo complexes including peroxo ring ( nA, n = 0-1) and hydroperoxo ( nB, n = 0-1) structures, which have been investigated using density functional theory (DFT). Moreover, the calculations on self-cycle mechanisms involving the two types of active structures of tungsten peroxo complexes with and without oxalic acid ligand have also been carried out at the B3LYP/[LANL2DZ/6-31G(d, p)] level. The highest energy barrier are 26.17 kcal/mol ( 0A, peroxo ring structure without oxalic acid ligand), 23.91 kcal/mol ( 1A, peroxo ring structure with oxalic acid ligand), 18.19 kcal/mol ( 0B, hydroperoxo structure without oxalic acid ligand) and 13.10 kcal/mol ( 1B, hydroperoxo structure with oxalic acid ligand) in the four potential energy profiles, respectively. The results indicate that both the energy barriers of active structure self-cycle processes with oxalic acid ligands are lower than those without oxalic acid ligands, so the active structures with oxalic acid ligands should be easier to recycle, which is in good agreement with our experimental results. However, due to the higher energy of product than that of the reactant, the energy profile of the self-cycle process of 1B shows that the recycle of 1B could not occur at all in theory. Moreover, the crystal data of peroxo ring structure with oxalic acid ligand could be found in some experimental references. Thus, the viewpoint that the peroxo ring active structure should be the real active structure has been proved in this paper.

Copper Complex in Poly(vinyl chloride) as a Nitric Oxide-Generating Catalyst for the Control of Nitrifying Bacterial Biofilms.

PubMed

Wonoputri, Vita; Gunawan, Cindy; Liu, Sanly; Barraud, Nicolas; Yee, Lachlan H; Lim, May; Amal, Rose

2015-10-14

In this study, catalytic generation of nitric oxide by a copper(II) complex embedded within a poly(vinyl chloride) matrix in the presence of nitrite (source of nitric oxide) and ascorbic acid (reducing agent) was shown to effectively control the formation and dispersion of nitrifying bacteria biofilms. Amperometric measurements indicated increased and prolonged generation of nitric oxide with the addition of the copper complex when compared to that with nitrite and ascorbic acid alone. The effectiveness of the copper complex-nitrite-ascorbic acid system for biofilm control was quantified using protein analysis, which showed enhanced biofilm suppression when the copper complex was used in comparison to that with nitrite and ascorbic acid treatment alone. Confocal laser scanning microscopy (CLSM) and LIVE/DEAD staining revealed a reduction in cell surface coverage without a loss of viability with the copper complex and up to 5 mM of nitrite and ascorbic acid, suggesting that the nitric oxide generated from the system inhibits proliferation of the cells on surfaces. Induction of nitric oxide production by the copper complex system also triggered the dispersal of pre-established biofilms. However, the addition of a high concentration of nitrite and ascorbic acid to a pre-established biofilm induced bacterial membrane damage and strongly decreased the metabolic activity of planktonic and biofilm cells, as revealed by CLSM with LIVE/DEAD staining and intracellular adenosine triphosphate measurements, respectively. This study highlights the utility of the catalytic generation of nitric oxide for the long-term suppression and removal of nitrifying bacterial biofilms.

Investigation of Pu(IV)-acetohydroxamic acid complex by solvent extraction with di(2-ethylhexyl) phosphoric acid

NASA Astrophysics Data System (ADS)

Brown, M. Alex; Paulenova, Alena; Tkac, Peter

2010-03-01

The stability constant of the Pu(IV)-acetohydroxamic acid complex Pu(AHA)3+ at 1 M ionic strength (pH = 0) has been investigated by method of solvent extraction. Di(2-ethylhexyl) phosphoric acid (HDEHP) was used to extract Pu(IV) from perchloric and nitric acid media at various AHA concentrations. Distribution ratios over a range of ligand concentrations were used in conjunction with graphical methods to obtain logβ1 = 14.3 ± 0.03 in perchloric acid. The stability constant determined from solutions in nitric acid was excluded because of the uncertainty in plutonium speciation.

Effect of amino acids on the interaction between cobalamin(II) and dehydroascorbic acid

NASA Astrophysics Data System (ADS)

Dereven'kov, I. A.; Thi, Thu Thuy Bui; Salnikov, D. S.; Makarov, S. V.

2016-03-01

The kinetics of the reaction between one-electron-reduced cobalamin (cobalamin(II), Cb(II)) and the two-electron-oxidized form of vitamin C (dehydroascorbic acid, DHA) with amino acids in an acidic medium is studied by conventional UV-Vis spectroscopy. It is shown that the oxidation of Cbl(II) by dehydroascorbic acid proceeds only in the presence of sulfur-containing amino acids (cysteine, acetylcysteine). A proposed reaction mechanism includes the step of amino acid coordination on the Co(II)-center through the sulfur atom, along with that of the interaction between this complex and DHA molecules, which results in the formation of ascorbyl radical and the corresponding Co(III) thiolate complex.

Spectroscopic and first-principles calculation studies of the chemical forms of palladium ion in nitric acid solution for development of disposal of high-level radioactive nuclear wastes

NASA Astrophysics Data System (ADS)

Watanabe, Shinta; Sato, Toshikazu; Yoshida, Tomoko; Nakaya, Masato; Yoshino, Masahito; Nagasaki, Takanori; Inaba, Yusuke; Takeshita, Kenji; Onoe, Jun

2018-04-01

We have investigated the chemical forms of palladium (Pd) ion in nitric acid solution, using XAFS/UV-vis spectroscopic and first-principles methods in order to develop the disposal of high-level radioactive nuclear liquid wastes (HLLW: radioactive metal ions in 2 M nitric acid solution). The results of theoretical calculations and XAFS/UV-vis spectroscopy indicate that Pd is a divalent ion and forms a square-planar complex structure coordinated with four nitrate ions, [Pd(NO3)4]2-, in nitric acid solution. This complex structure is also thermodynamically predicted to be most stable among complexes [Pd(H2O)x(NO3)4-x]x-2 (x = 0-4). Since the overall feature of UV-vis spectra of the Pd complex was independent of nitric acid concentration in the range 1-6 M, the structure of the Pd complex remains unchanged in this range. Furthermore, we examined the influence of γ-ray radiation on the [Pd(NO3)4]2- complex, using UV-vis spectroscopy, and found that UV-vis spectra seemed not to be changed even after 1.0 MGy irradiation. This implies that the Pd complex structure will be still stable in actual HLLW. These findings obtained above are useful information to develop the vitrification processes for disposal of HLLW.

Effect of CMC Molecular Weight on Acid-Induced Gelation of Heated WPI-CMC Soluble Complex.

PubMed

Huan, Yan; Zhang, Sha; Vardhanabhuti, Bongkosh

2016-02-01

Acid-induced gelation properties of heated whey protein isolate (WPI) and carboxymethylcellulose (CMC) soluble complex were investigated as a function of CMC molecular weight (270, 680, and 750 kDa) and concentrations (0% to 0.125%). Heated WPI-CMC soluble complex with 6% protein was made by heating biopolymers together at pH 7.0 and 85 °C for 30 min and diluted to 5% protein before acid-induced gelation. Acid-induced gel formed from heated WPI-CMC complexes exhibited increased hardness and decreased water holding capacity with increasing CMC concentrations but gel strength decreased at higher CMC content. The highest gel strength was observed with CMC 750 k at 0.05%. Gels with low CMC concentration showed homogenous microstructure which was independent of CMC molecular weight, while increasing CMC concentration led to microphase separation with higher CMC molecular weight showing more extensive phase separation. When heated WPI-CMC complexes were prepared at 9% protein the acid gels showed improved gel hardness and water holding capacity, which was supported by the more interconnected protein network with less porosity when compared to complexes heated at 6% protein. It is concluded that protein concentration and biopolymer ratio during complex formation are the major factors affecting gel properties while the effect of CMC molecular weight was less significant. © 2016 Institute of Food Technologists®

Comparisons of pilot performance in simulated and actual flight. [effects of ingested barbiturates

NASA Technical Reports Server (NTRS)

Billings, C. E.; Gerke, R. J.; Wick, R. L., Jr.

1975-01-01

Five highly experienced professional pilots performed instrument landing system approaches under simulated instrument flight conditions in a Cessna 172 airplane and in a Link-Singer GAT-1 simulator while under the influence of orally administered secobarbital (0, 100, and 200 mg). Tracking performance in two axes and airspeed control were evaluated continuously during each approach. Error and RMS variability were about half as large in the simulator as in the airplane. The observed data were more strongly associated with the drug level in the simulator than in the airplane. Further, the drug-related effects were more consistent in the simulator. Improvement in performance suggestive of learning effects were seen in the simulator, but not in actual flight.

Pentobarbital quantitation using EMIT serum barbiturate assay reagents: application to monitoring of high-dose pentobarbital therapy.

PubMed

Pape, B E; Cary, P L; Clay, L C; Godolphin, W

1983-01-01

Pentobarbital serum concentrations associated with a high-dose therapeutic regimen were determined using EMIT immunoassay reagents. Replicate analyses of serum controls resulted in a within-assay coefficient of variation of 5.0% and a between-assay coefficient of variation of 10%. Regression analysis of 44 serum samples analyzed by this technique (y) and a reference procedure (x) were y = 0.98x + 3.6 (r = 0.98; x = ultraviolet spectroscopy) and y = 1.04x + 2.4 (r = 0.96; x = high-performance liquid chromatography). Clinical evaluation of the results indicates the immunoassay is sufficiently sensitive and selective for pentobarbital to allow accurate quantitation within the therapeutic range associated with high-dose therapy.

Effect of peptidase inhibition on the pattern of intraspinally released immunoreactive substance P detected with antibody microprobes.

PubMed

Duggan, A W; Schaible, H G; Hope, P J; Lang, C W

1992-05-08

Antibody microprobes bearing antibodies to the C-terminus of substance P (SP) were used to measure release of immunoreactive (ir) SP in the dorsal horn of barbiturate anaesthetized spinal cats. Electrical stimulation of unmyelinated primary afferents of the ipsilateral tibial nerve produced a relatively localised release of ir SP in the superficial dorsal horn. Prior microinjection of the peptidase inhibitors kelatorphan and enalaprilat in the dorsal horn resulted in ir SP being detected over the whole of the dorsal horn and the overlying dorsal column. This pattern had previously been observed with evoked release of ir neurokinin A and supports the proposal that a slow degradation results in a neuropeptide accessing many sites remote from sites of release.

Role of DNA conformation & energetic insights in Msx-1-DNA recognition as revealed by molecular dynamics studies on specific and nonspecific complexes.

PubMed

Kachhap, Sangita; Singh, Balvinder

2015-01-01

In most of homeodomain-DNA complexes, glutamine or lysine is present at 50th position and interacts with 5th and 6th nucleotide of core recognition region. Molecular dynamics simulations of Msx-1-DNA complex (Q50-TG) and its variant complexes, that is specific (Q50K-CC), nonspecific (Q50-CC) having mutation in DNA and (Q50K-TG) in protein, have been carried out. Analysis of protein-DNA interactions and structure of DNA in specific and nonspecific complexes show that amino acid residues use sequence-dependent shape of DNA to interact. The binding free energies of all four complexes were analysed to define role of amino acid residue at 50th position in terms of binding strength considering the variation in DNA on stability of protein-DNA complexes. The order of stability of protein-DNA complexes shows that specific complexes are more stable than nonspecific ones. Decomposition analysis shows that N-terminal amino acid residues have been found to contribute maximally in binding free energy of protein-DNA complexes. Among specific protein-DNA complexes, K50 contributes more as compared to Q50 towards binding free energy in respective complexes. The sequence dependence of local conformation of DNA enables Q50/Q50K to make hydrogen bond with nucleotide(s) of DNA. The changes in amino acid sequence of protein are accommodated and stabilized around TAAT core region of DNA having variation in nucleotides.

Sphingolipid biosynthesis upregulation by TOR Complex 2-Ypk1 signaling during yeast adaptive response to acetic acid stress

PubMed Central

Guerreiro, Joana F.; Muir, Alexander; Ramachandran, Subramaniam; Thorner, Jeremy; Sá-Correia, Isabel

2016-01-01

Acetic acid-induced inhibition of yeast growth and metabolism limits the productivity of industrial fermentation processes, especially when lignocellulosic hydrolysates are used as feedstock in industrial biotechnology. Tolerance to acetic acid of food spoilage yeasts is also a problem in the preservation of acidic foods and beverages. Thus, understanding the molecular mechanisms underlying adaptation and tolerance to acetic acid stress is increasingly important in industrial biotechnology and the food industry. Prior genetic screens for S. cerevisiae mutants with increased sensitivity to acetic acid identified loss-of-function mutations in the YPK1 gene, which encodes a protein kinase activated by the Target of Rapamycin (TOR) Complex 2 (TORC2). We show here by several independent criteria that TORC2-Ypk1 signaling is stimulated in response to acetic acid stress. Moreover, we demonstrate that TORC2-mediated Ypk1 phosphorylation and activation is necessary for acetic acid tolerance, and occurs independently of Hrk1, a protein kinase previously implicated in the cellular response to acetic acid. In addition, we show that TORC2-Ypk1-mediated activation of L-serine: palmitoyl-CoA acyltransferase, the enzyme complex that catalyzes the first committed step of sphingolipid biosynthesis, is required for acetic acid tolerance. Furthermore, analysis of the sphingolipid pathway using inhibitors and mutants indicates that it is production of certain complex sphingolipids that contributes to conferring acetic acid tolerance. Consistent with that conclusion, promoting sphingolipid synthesis by adding exogenous long-chain base precursor phytosphingosine to the growth medium enhanced acetic acid tolerance. Thus, appropriate modulation of the TORC2-Ypk1-sphingolipid axis in industrial yeast strains may have utility in improving fermentations of acetic acid-containing feedstocks. PMID:27671892

Method for identifying and quantifying nucleic acid sequence aberrations

DOEpatents

Lucas, Joe N.; Straume, Tore; Bogen, Kenneth T.

1998-01-01

A method for detecting nucleic acid sequence aberrations by detecting nucleic acid sequences having both a first and a second nucleic acid sequence type, the presence of the first and second sequence type on the same nucleic acid sequence indicating the presence of a nucleic acid sequence aberration. The method uses a first hybridization probe which includes a nucleic acid sequence that is complementary to a first sequence type and a first complexing agent capable of attaching to a second complexing agent and a second hybridization probe which includes a nucleic acid sequence that selectively hybridizes to the second nucleic acid sequence type over the first sequence type and includes a detectable marker for detecting the second hybridization probe.

Method for identifying and quantifying nucleic acid sequence aberrations

DOEpatents

Lucas, J.N.; Straume, T.; Bogen, K.T.

1998-07-21

A method is disclosed for detecting nucleic acid sequence aberrations by detecting nucleic acid sequences having both a first and a second nucleic acid sequence type, the presence of the first and second sequence type on the same nucleic acid sequence indicating the presence of a nucleic acid sequence aberration. The method uses a first hybridization probe which includes a nucleic acid sequence that is complementary to a first sequence type and a first complexing agent capable of attaching to a second complexing agent and a second hybridization probe which includes a nucleic acid sequence that selectively hybridizes to the second nucleic acid sequence type over the first sequence type and includes a detectable marker for detecting the second hybridization probe. 11 figs.

Determination of thermodynamic values of acidic dissociation constants and complexation constants of profens and their utilization for optimization of separation conditions by Simul 5 Complex.

PubMed

Riesová, Martina; Svobodová, Jana; Ušelová, Kateřina; Tošner, Zdeněk; Zusková, Iva; Gaš, Bohuslav

2014-10-17

In this paper we determine acid dissociation constants, limiting ionic mobilities, complexation constants with β-cyclodextrin or heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin, and mobilities of resulting complexes of profens, using capillary zone electrophoresis and affinity capillary electrophoresis. Complexation parameters are determined for both neutral and fully charged forms of profens and further corrected for actual ionic strength and variable viscosity in order to obtain thermodynamic values of complexation constants. The accuracy of obtained complexation parameters is verified by multidimensional nonlinear regression of affinity capillary electrophoretic data, which provides the acid dissociation and complexation parameters within one set of measurements, and by NMR technique. A good agreement among all discussed methods was obtained. Determined complexation parameters were used as input parameters for simulations of electrophoretic separation of profens by Simul 5 Complex. An excellent agreement of experimental and simulated results was achieved in terms of positions, shapes, and amplitudes of analyte peaks, confirming the applicability of Simul 5 Complex to complex systems, and accuracy of obtained physical-chemical constants. Simultaneously, we were able to demonstrate the influence of electromigration dispersion on the separation efficiency, which is not possible using the common theoretical approaches, and predict the electromigration order reversals of profen peaks. We have shown that determined acid dissociation and complexation parameters in combination with tool Simul 5 Complex software can be used for optimization of separation conditions in capillary electrophoresis. Copyright © 2014 Elsevier B.V. All rights reserved.

Host-guest inclusion system of glycyrrhetic acid with polyamine-β-cyclodextrin: Preparation, characterization, and anticancer activity

NASA Astrophysics Data System (ADS)

Shen, Zhi; Qin, Qi; Liao, Xiali; Yang, Bo

2017-12-01

The inclusion complexation behaviors of glycyrrhetic acid (CTA) with four polyamine-modified β-cyclodextrins (CDs) have been investigated by 1H and 2D NMR, thermal gravimetric analysis, X-ray power diffraction and scanning electron microscopy. The results showed that Glycyrrhetic acid was encapsulated into the cavity of cyclodextrin to form the complexes with 1:1 stoichiometry. The water solubility of GTA was significantly enhanced by inclusion complexation with polyamine-modified β-cyclodextrins. The calculated IC50 values indicated that the antitumor activities of inclusion complexes were better than that of GTA. Satisfactory aqueous solubility, along with high thermal stability of inclusion complexes will be potentially useful for their application on the formulation design of natural medicine.

Photocatalytic CO2 reduction with high turnover frequency and selectivity of formic acid formation using Ru(II) multinuclear complexes.

PubMed

Tamaki, Yusuke; Morimoto, Tatsuki; Koike, Kazuhide; Ishitani, Osamu

2012-09-25

Previously undescribed supramolecules constructed with various ratios of two kinds of Ru(II) complexes-a photosensitizer and a catalyst-were synthesized. These complexes can photocatalyze the reduction of CO(2) to formic acid with high selectivity and durability using a wide range of wavelengths of visible light and NADH model compounds as electron donors in a mixed solution of dimethylformamide-triethanolamine. Using a higher ratio of the photosensitizer unit to the catalyst unit led to a higher yield of formic acid. In particular, of the reported photocatalysts, a trinuclear complex with two photosensitizer units and one catalyst unit photocatalyzed CO(2) reduction (Φ(HCOOH) = 0.061, TON(HCOOH) = 671) with the fastest reaction rate (TOF(HCOOH) = 11.6 min(-1)). On the other hand, photocatalyses of a mixed system containing two kinds of model mononuclear Ru(II) complexes, and supramolecules with a higher ratio of the catalyst unit were much less efficient, and black oligomers and polymers were produced from the Ru complexes during photocatalytic reactions, which reduced the yield of formic acid. The photocatalytic formation of formic acid using the supramolecules described herein proceeds via two sequential processes: the photochemical reduction of the photosensitizer unit by NADH model compounds and intramolecular electron transfer to the catalyst unit.

Thermodynamic and Spectroscopic Studies of Trivalent f -element Complexation with Ethylenediamine- N,N '-di(acetylglycine)- N,N '-diacetic Acid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heathman, Colt R.; Grimes, Travis S.; Zalupski, Peter R.

In this study, the coordination behavior and thermodynamic features of complexation of trivalent lanthanides and americium by ethylenediamine- N,N'-di(acetylglycine)- N,N'-diacetic acid (EDDAG-DA) (bisamide-substituted-EDTA) were investigated by potentiometric and spectroscopic techniques. Acid dissociation constants (K a) and complexation constants (β) of lanthanides (except Pm) were determined by potentiometric analysis. Absorption spectroscopy was used to determine stability constants for the binding of trivalent americium and neodymium by EDDAG-DA under similar conditions. The potentiometry revealed 5 discernible protonation constants and 3 distinct metal–ligand complexes (identified as ML –, MHL, and MH 2L +). Time-resolved fluorescence studies of Eu-(EDDAG-DA) solutions (at varying pH) identifiedmore » a constant inner-sphere hydration number of 3, suggesting that glycine functionalities contained in the amide pendant arms are not involved in metal complexation and are protonated under more acidic conditions. The thermodynamic studies identified that f-element coordination by EDDAG-DA is similar to that observed for ethylenediamine- N,N,N',N'-tetraacetic acid (EDTA). However, coordination via two amidic oxygens of EDDAG-DA lowers its trivalent f-element complex stability by roughly 3 orders of magnitude relative to EDTA.« less

Thermodynamic and Spectroscopic Studies of Trivalent f -element Complexation with Ethylenediamine- N,N '-di(acetylglycine)- N,N '-diacetic Acid

DOE PAGES

Heathman, Colt R.; Grimes, Travis S.; Zalupski, Peter R.

2016-03-21

In this study, the coordination behavior and thermodynamic features of complexation of trivalent lanthanides and americium by ethylenediamine- N,N'-di(acetylglycine)- N,N'-diacetic acid (EDDAG-DA) (bisamide-substituted-EDTA) were investigated by potentiometric and spectroscopic techniques. Acid dissociation constants (K a) and complexation constants (β) of lanthanides (except Pm) were determined by potentiometric analysis. Absorption spectroscopy was used to determine stability constants for the binding of trivalent americium and neodymium by EDDAG-DA under similar conditions. The potentiometry revealed 5 discernible protonation constants and 3 distinct metal–ligand complexes (identified as ML –, MHL, and MH 2L +). Time-resolved fluorescence studies of Eu-(EDDAG-DA) solutions (at varying pH) identifiedmore » a constant inner-sphere hydration number of 3, suggesting that glycine functionalities contained in the amide pendant arms are not involved in metal complexation and are protonated under more acidic conditions. The thermodynamic studies identified that f-element coordination by EDDAG-DA is similar to that observed for ethylenediamine- N,N,N',N'-tetraacetic acid (EDTA). However, coordination via two amidic oxygens of EDDAG-DA lowers its trivalent f-element complex stability by roughly 3 orders of magnitude relative to EDTA.« less

Structural study of Cu(II) complexes with benzo[b]furancarboxylic acids

NASA Astrophysics Data System (ADS)

Kalinowska, Diana; Klepka, Marcin T.; Wolska, Anna; Drzewiecka-Antonik, Aleksandra; Ostrowska, Kinga; Struga, Marta

2017-11-01

Four Cu(II) complexes with 2- and 3-benzo[b]furancarboxylic acids have been synthesized and characterized using combination of two spectroscopic techniques. These techniques were: (i) FTIR and (ii) XAFS. FTIR analysis confirmed that complexes were formed and gave insight into identification of possible coordinating groups to the metallic center. XANES analysis indicated that the oxidation state of Cu is +2. EXAFS analysis allowed to identify that the first coordination sphere is formed by 4-5 oxygen atoms with the Cu-O distances around 2 Å. Combining these techniques it was possible to structurally describe novel Cu(II) complexes with benzo[b]furancarboxylic acids.

INTERRELATION BETWEEN ACTIVATION AND POLYMERIZATION IN GRAMICIDIN S BIOSYNTHESIS*

PubMed Central

Kleinkauf, Horst; Gevers, Wieland; Lipmann, Fritz

1969-01-01

The nucleic acid-independent biosynthesis of the peptide antibiotic gramicidin S results from the interaction of an enzyme bearing phenylalanine in activated form with a polyenzyme system charged with the other four component amino acids. After reaction with ATP, magnesium, and any or all of its amino acid substrates, the polyenzyme system (mol wt 280,000) yields complexes containing AMP and the respective amino acids in the proportion of 1 to 2. Similar complexes are formed by another enzyme (mol wt 100,000) on incubation with ATP, magnesium, and L- or D-phenylalanine. The amino acids are probably bound as aminoacyl adenylates and then transferred to another function on the enzyme. Initiation of polymerization is achieved by combination of the two complexes. No ATP is needed for completion of synthesis, and free intermediates are not released. Enzyme organization and specificity are responsible for the ordering of the amino acid sequence. PMID:5253659

Carbonic Anhydrase Inhibitors. Part 91. Metal Complexes of Heterocyclic Sulfonamides as Potential Pharmacological Agents in the Treatment of Gastric Acid Secretion Imbalances

PubMed Central

Ilies, Marc A.; Scozzafava, Andrea

2000-01-01

Zinc, magnesium, aluminum and copper complexes of several potent, clinically used carbonic anhydrase (CA) sulfonamide inhibitors, such as acetazolamide, methazolamide, ethoxzolamide and benzolamide were tested for their possible applications as antacids, in experimental animals. Gastric acid secretion parameters 3 days after treatment with these CA inhibitors (2 × 500 mg, twice a day), in dogs with chronic gastric fistulas, led to the observation that the gastric acid parameters BAO (the basal acid output), and MAO (the maximal acid output after stimulation with histamine) were drastically reduced, as compared to the same parameters in animals that did not receive these enzyme inhibitors. These are promising results for the possible use of metal complexes of heterocyclic sulfonamides as treatment alternatives (alone or in combination with other drugs) for gastric acid secretion imbalances. PMID:18475926

Asymmetric synthesis of α-amino acids via homologation of Ni(II) complexes of glycine Schiff bases. Part 2: aldol, Mannich addition reactions, deracemization and (S) to (R) interconversion of α-amino acids.

PubMed

Sorochinsky, Alexander E; Aceña, José Luis; Moriwaki, Hiroki; Sato, Tatsunori; Soloshonok, Vadim

2013-11-01

This review provides a comprehensive treatment of literature data dealing with asymmetric synthesis of α-amino-β-hydroxy and α,β-diamino acids via homologation of chiral Ni(II) complexes of glycine Schiff bases using aldol and Mannich-type reactions. These reactions proceed with synthetically useful chemical yields and thermodynamically controlled stereoselectivity and allow direct introduction of two stereogenic centers in a single operation with predictable stereochemical outcome. Furthermore, new application of Ni(II) complexes of α-amino acids Schiff bases for deracemization of racemic α-amino acids and (S) to (R) interconversion providing additional synthetic opportunities for preparation of enantiomerically pure α-amino acids, is also reviewed. Origin of observed diastereo-/enantioselectivity in the aldol, Mannich-type and deracemization reactions, generality and limitations of these methodologies are critically discussed.

Structure and function of human α-lactalbumin made lethal to tumor cells (HAMLET)-type complexes.

PubMed

Mossberg, Ann-Kristin; Hun Mok, Kenneth; Morozova-Roche, Ludmilla A; Svanborg, Catharina

2010-11-01

Human α-lactalbumin made lethal to tumor cells (HAMLET) and equine lysozyme with oleic acid (ELOA) are complexes consisting of protein and fatty acid that exhibit cytotoxic activities, drastically differing from the activity of their respective proteinaceous compounds. Since the discovery of HAMLET in the 1990s, a wealth of information has been accumulated, illuminating the structural, functional and therapeutic properties of protein complexes with oleic acid, which is summarized in this review. In vitro, both HAMLET and ELOA are produced by using ion-exchange columns preconditioned with oleic acid. However, the complex of human α-lactalbumin with oleic acid with the antitumor activity of HAMLET was found to be naturally present in the acidic fraction of human milk, where it was discovered by serendipity. Structural studies have shown that α-lactalbumin in HAMLET and lysozyme in ELOA are partially unfolded, 'molten-globule'-like, thereby rendering the complexes dynamic and in conformational exchange. HAMLET exists in the monomeric form, whereas ELOA mostly exists as oligomers and the fatty acid stoichiometry varies, with HAMLET holding an average of approximately five oleic acid molecules, whereas ELOA contains a considerably larger number (11- 48). Potent tumoricidal activity is found in both HAMLET and ELOA, and HAMLET has also shown strong potential as an antitumor drug in different in vivo animal models and clinical studies. The gain of new, beneficial function upon partial protein unfolding and fatty acid binding is a remarkable phenomenon, and may reflect a significant generic route of functional diversification of proteins via varying their conformational states and associated ligands. © 2010 The Authors Journal compilation © 2010 FEBS.

Aqua complexes of 18—crown-6 with H 3PO 4, H 2TiF 6, and HNO 3: synthesis and vibrational spectra

NASA Astrophysics Data System (ADS)

Chénevert, R.; Rodrigue, A.; Chamberland, D.; Ouellet, J.; Savoie, R.

1985-11-01

Neutral-component complexes of 2:3:1 (acid:water:18-crown-6) stoichiometry have been obtained with H 3PO 4 and H 2TiF 6. These adducts have been studied by infrared and Raman spectroscopy, along with the corresponding (HNO 3-H 1O) 2-18-crown-6 complex, whose synthesis has already been reported. The spectra indicate that the crown ether has a highly regular conformation in these complexes. In those with H 3PO 4 and HNO 3, the binding of the acid molecule to the ether takes place through a H 2O linker, the strength of the XOH⋯OH 2 hydrogen bond being directly related to the p K a of the acid. With HNO 3, the acidic proton appears to be delocalized between the two oxygen atoms, giving a pseudo H 2O + ion whereas in the corresponding deuterocompound the D atom remains associated with the acid.

An approach to complex acid-base problems

PubMed Central

Herd, Anthony M.

2005-01-01

OBJECTIVE To review rules and formulas for solving even the most complex acid-base problems. SOURCES OF INFORMATION MEDLINE was searched from January 1966 to December 2003. The search was limited to English-language review articles involving human subjects. Nine relevant review papers were found and provide the background. As this information is well established and widely accepted, it is not judged for strength of evidence, as is standard practice. MAIN MESSAGE An understanding of the body’s responses to acidemia or alkalemia can be gained through a set of four rules and two formulas that can be used to interpret almost any acid-base problems. Physicians should, however, remember the “golden rule” of acid-base interpretation: always look at a patient’s clinical condition. CONCLUSION Physicians practising in acute care settings commonly encounter acid-base disturbances. While some of these are relatively simple and easy to interpret, some are more complex. Even complex cases can be resolved using the four rules and two formulas. PMID:15751566

A theoretical study on the mechanistic highlights behind the Brønsted-acid dependent mer-fac isomerization of homoleptic carbenic iridium complexes for PhOLEDs.

PubMed

Setzer, Tobias; Lennartz, Christian; Dreuw, Andreas

2017-06-06

Recently, a successful Brønsted-acid mediated geometric isomerization of the meridional homoleptic carbenic iridium(iii) complexes tris-(N-phenyl,N-methyl-benzimidazol-2-yl)iridium(iii) (1) and tris-(N-phenyl,N-benzyl-benzimidazol-2-yl)iridium(iii) (2) into their facial form has been reported. In the present work the pronounced acid-dependency of this particular isomerization procedure is revisited and additional mechanistic pathways are taken into account. Moreover, the acid-induced material decomposition is addressed. All calculations are carried out using density functional theory (DFT) while the environmental effects in solution are accounted for by the COSMO-RS model. The simulated results clearly reveal the outstanding importance of the complex interplay between acid strength, coordinating power of the corresponding base and the steric influence of the ligand system in contrast to the plain calculation of minimum energy pathways for selected complexes. Eventually, general rules to enhance the material-specific reaction yields are provided.

Effect of amylopectin on the rheological properties of aqueous dispersions of starch-sodium palmitate complexes

USDA-ARS?s Scientific Manuscript database

Aqueous dispersions of normal and high-amylose corn starch were steam jet cooked and blended with aqueous solutions of sodium palmitate to form amylose inclusion complexes. Partial conversion of complexed sodium palmitate to palmitic acid by addition of acetic acid led to the formation of gels. Bl...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin, Xin; Zhou, Pei; Zheng, Chunying

A copper complex ([Cu(py){sub 2}(L){sub 2}]·2CH{sub 3}OH){sub n} (HL=(E)-3-(3-hydroxyl-phenyl)-acrylic acid) (1) with acrylic acid ligand was synthesized and structurally analyzed by IR, elemental analysis, TGA and the single-crystal X-ray diffraction methods. It is the first time to find that phenolic hydroxyl of L coordinates to Cu(II). Complex 1 exhibits 1D chain by a double-bridge of ligands, and the 3D supramolecular framework in complex 1 is constructed by π–π stacking interactions and van der Waals Contacts among the 1D chains. The magnetic properties of complex 1 have been studied. - Graphical abstract: A copper complex based on (E)-3-(3-hydroxyl-phenyl)-acrylic acid in amore » novel coordinated way was synthesized and a ferromagnetic exchange interactions between neighboring Cu(II) ions has be achieved. - Highlights: • A new copper complex with acrylic acid ligand was synthesized and analyzed. • We find the phenolic hydroxyl of MCA ligand coordinates to metal ion firstly. • A ferromagnetic exchange interactions between Cu(II) ions has been achieved.« less

Effect of the ortho-Hydroxyl Groups on a Bipyridine Ligand of Iridium Complexes for the High-Pressure Gas Generation from the Catalytic Decomposition of Formic Acid.

PubMed

Iguchi, Masayuki; Zhong, Heng; Himeda, Yuichiro; Kawanami, Hajime

2017-12-14

The hydroxyl groups of a 2,2'-bipyridine (bpy) ligand near the metal center activated the catalytic performance of the Ir complex for the dehydrogenation of formic acid at high pressure. The position of the hydroxyl groups on the ligand affected the catalytic durability for the high-pressure H 2 generation through the decomposition of formic acid. The Ir complex with a bipyridine ligand functionalized with para-hydroxyl groups shows a good durability with a constant catalytic activity during the reaction even under high-pressure conditions, whereas deactivation was observed for an Ir complex with a bipyridine ligand with ortho-hydroxyl groups (2). In the presence of high-pressure H 2 , complex 2 decomposed into the ligand and an Ir trihydride complex through the isomerization of the bpy ligand. This work provides the development of a durable catalyst for the high-pressure H 2 production from formic acid. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Silver(I) complexes of 2,4-dihydroxybenzaldehyde-amino acid Schiff bases-Novel noncompetitive α-glucosidase inhibitors.

PubMed

Zheng, Jingwei; Ma, Lin

2015-01-01

A series of silver(I) complexes of 2,4-dihydroxybenzaldehyde-amino acid Schiff bases were designed and tested for α-glucosidase inhibition. Our results indicate that all the silver complexes (4a-18a) possessed strong inhibitory activity at μmolL(-1) level, especially glutamine (12a) and histidine (18a) Schiff base silver(I) complexes exhibited an IC50 value of less than 0.01μmolL(-1). This series of compounds exhibited noncompetitive inhibition characteristics in kinetic studies. In addition, we investigated the mechanism of inhibition and the structure-activity relationships of the amino acid Schiff base silver complexes. Our results reveal that Schiff base silver complexes may be explored for their therapeutic potential as alternatives of α-glucosidase inhibitors. Copyright © 2015 Elsevier Ltd. All rights reserved.

Higher value films prepared from poly(vinyl alcohol) and amylose-fatty acid derivatives inclusion complexes

USDA-ARS?s Scientific Manuscript database

Water soluble amylose fatty acid and fatty ammonium salt inclusion complexes (AIC) were prepared by jet cooked high amylose corn starch with water soluble salts of long chain fatty acids or fatty amines. The formation of AIC was confirmed by X-ray diffraction of freeze-dried samples. After dissoluti...

Ursolic Acid Hydrazide Based Organometallic Complexes: Synthesis, Characterization, Antibacterial, Antioxidant and Docking Studies

NASA Astrophysics Data System (ADS)

Jabeen, Muafia; Ahmad, Sajjad; Shahid, Khadija; Sadiq, Abdul; Rashid, Umer

2018-03-01

In the current research work,eleven metal complexes were synthesized from the hydrazide derivative of ursolic acid. Metal complexes of tin, antimony and iron were synthesized and characterized by FT-IR and NMR spectroscopy. The antibacterial and antioxidant activities were performed for these complexes, which revealed that the metal complexes synthesized are more potent than their parent compounds. We observed that antioxidant activity showed by triphenyltin complex was significant and least activity have been shown by antimony trichloride complex.The synthesized metal complexes were then evaluated against two Gram-negative and two Gram-positive bacterial strains. Triphenyl tin complex emerged as potent antibacterial agent with MIC value of 8 μg/ml each against Shigellaspp, S. typhi and S. aureus. While, the MIC value againstS. pneumoniae is 4 μg/ml.Computational docking studies were carried out on molecular targets to interpret the results of antioxidant and antibacterial activities. Based on the results, it may be inferred that the metal complexes of ursolic acid are more active as compared to the parent drug and may be proved for some other pharmacological potential by further analysis.

Spectroscopic and physical measurements on charge-transfer complexes: Interactions between norfloxacin and ciprofloxacin drugs with picric acid and 3,5-dinitrobenzoic acid acceptors

NASA Astrophysics Data System (ADS)

Refat, Moamen S.; Elfalaky, A.; Elesh, Eman

2011-03-01

Charge-transfer complexes formed between norfloxacin (nor) or ciprofloxacin (cip) drugs as donors with picric acid (PA) and/or 3,5-dinitrobenzoic acid (DNB) as π-acceptors have been studied spectrophotometrically in methanol solvent at room temperature. The results indicated the formation of CT-complexes with molar ratio1:1 between donor and acceptor at maximum CT-bands. In the terms of formation constant ( KCT), molar extinction coefficient ( ɛCT), standard free energy (Δ Go), oscillator strength ( f), transition dipole moment (μ), resonance energy ( RN) and ionization potential ( ID) were estimated. IR, H NMR, UV-Vis techniques, elemental analyses (CHN) and TG-DTG investigations were used to characterize the structural of charge-transfer complexes. It indicates that the CT interaction was associated with a proton migration from each acceptor to nor or cip donors which followed by appearing intermolecular hydrogen bond. In addition, X-ray investigation was carried out to scrutinize the crystal structure of the resulted CT-complexes.

Synthesis, crystal structures, molecular docking, and in vitro biological activities evaluation of transition metal complexes with 4-(3,4-dichlorophenyl) piperazine-1-carboxylic acid

NASA Astrophysics Data System (ADS)

Chen, Zhi-Jian; Chen, Ya-Na; Xu, Chun-Na; Zhao, Shan-Shan; Cao, Qi-Yue; Qian, Shao-Song; Qin, Jie; Zhu, Hai-Liang

2016-08-01

Three novel mononuclear complexes, [MⅡ(L)2·2H2O], (M = Cu, Ni or Cd; HL = 4-(3,4-dichlorophenyl)piperazine-1-carboxylic acid)were synthesized and structurally determined by single-crystal X-ray diffraction. Molecular docking study preliminarily revealed that complex 1 had potential urease inhibitory activity. In accordance with the result of calculation, in vitro tests of the inhibitory activities of complexes 1-3 against jack bean urease showed complex 1 (IC50 = 8.17 ± 0.91 μM) had better inhibitory activities than the positive reference acetohydroxamic acid (AHA) (IC50 = 26.99 ± 1.43 μM), while complexes 2 and 3 showed no inhibitory activities., kinetics study was carried out to explore the mechanism of the inhibiting of the enzyme, and the result indicated that complex 1 was a competitive inhibitor of urease. Albumin binding experiment and in vitro toxicity evaluation of complex 1 were implemented to explore its Pharmacological properties.

An ion-pair principle for enantioseparations of basic analytes by nonaqueous capillary electrophoresis using the di-n-butyl L-tartrate-boric acid complex as chiral selector.

PubMed

Wang, Li-Juan; Liu, Xiu-Feng; Lu, Qie-Nan; Yang, Geng-Liang; Chen, Xing-Guo

2013-04-05

A chiral recognition mechanism of ion-pair principle has been proposed in this study. It rationalized the enantioseparations of some basic analytes using the complex of di-n-butyl l-tartrate and boric acid as the chiral selector in methanolic background electrolytes (BGEs) by nonaqueous capillary electrophoresis (NACE). An approach of mass spectrometer (MS) directly confirmed that triethylamine promoted the formation of negatively charged di-n-butyl l-tartrate-boric acid complex chiral counter ion with a complex ratio of 2:1. And the negatively charged counter ion was the real chiral selector in the ion-pair principle enantioseparations. It was assumed that triethylamine should play its role by adjusting the apparent acidity (pH*) of the running buffer to a higher value. Consequently, the effects of various basic electrolytes including inorganic and organic ones on the enantioseparations in NACE were investigated. The results showed that most of the basic electrolytes tested were favorable for the enantioseparations of basic analytes using di-n-butyl l-tartrate-boric acid complex as the chiral ion-pair selector. Copyright © 2013 Elsevier B.V. All rights reserved.

Omega-3 fatty acids: new insights into the pharmacology and biology of docosahexaenoic acid, docosapentaenoic acid, and eicosapentaenoic acid.

PubMed

Davidson, Michael H

2013-12-01

Fish oil contains a complex mixture of omega-3 fatty acids, which are predominantly eicosapentaenoic acid (EPA), docosapentaenoic acid, and docosahexaenoic acid (DHA). Each of these omega-3 fatty acids has distinct biological effects that may have variable clinical effects. In addition, plasma levels of omega-3 fatty acids are affected not only by dietary intake, but also by the polymorphisms of coding genes fatty acid desaturase 1-3 for the desaturase enzymes that convert short-chain polyunsaturated fatty acids to long-chain polyunsaturated fatty acids. The clinical significance of this new understanding regarding the complexity of omega-3 fatty acid biology is the purpose of this review. FADS polymorphisms that result in either lower levels of long-chain omega-3 fatty acids or higher levels of long-chain omega-6 polyunsaturated fatty acids, such as arachidonic acid, are associated with dyslipidemia and other cardiovascular risk factors. EPA and DHA have differences in their effects on lipoprotein metabolism, in which EPA, with a more potent peroxisome proliferator-activated receptor-alpha effect, decreases hepatic lipogenesis, whereas DHA not only enhances VLDL lipolysis, resulting in greater conversion to LDL, but also increases HDL cholesterol and larger, more buoyant LDL particles. Overall, these results emphasize that blood concentrations of individual long-chain polyunsaturated fatty acids, which reflect both dietary intake and metabolic influences, may have independent, but also complementary- biological effects and reinforce the need to potentially provide a complex mixture of omega-3 fatty acids to maximize cardiovascular risk reduction.

Spectroscopic evidence for organic diacid complexation with dissolved silica in aqueous systems—I. Oxalic acid

USGS Publications Warehouse

Marley, N.A.; Bennett, P.; Janecky, D.R.; Gaffney, J.S.

1989-01-01

Increased solubility of quartz and mobilization in contaminated groundwater due to the complexation with dissolved organic acids has been recently proposed [Bennett and Siegel, Nature326, 684–686 (1987)]. Using laser Raman and Fourier transform infrared spectroscopies, we have examined mixed solutions of oxalic and silicic acids at near neutral pH in the tenth molar concentration ranges in an attempt to directly observe the proposed organo-silicate complexes.In both laser Raman and infrared spectra, product bands were observed that indicate an oxalate/silicic acid ester is being formed in the reaction. These data support the observation that organic diacids can lead to enhanced solubility of quartz in hydrogeological systems.

Synthesis and characterization of Mono-Aqua-Pentakis (Isoni-Cotinic Acid) Nickel (II) Sulfate Trihydrate

NASA Astrophysics Data System (ADS)

Syaima, H.; Rahardjo, S. B.; Amanati, N.

2018-05-01

A complex of nickel (II) with isonicotinic acid (asint) was successfully obtained. The complex was synthesized in 1:2 mole ratio of metal to the ligand in methanol. The percentage of nickel was 6.91% determined by Atomic Absorption Spectroscopy (AAS). Therefore, the predicted formula was Ni(asint)5SO4(H2O)4. The molar conductivity of the complex was measured by conductivity meter corresponding to 1:1 electrolyte. The thermal analysis of the formed complex was determined by Differential Thermal Analysis (DTA) indicating that the complex contains four water molecules as ligand and hydrates. The magnetic susceptibility measurement showed that the complex was paramagnetic with μeff= 3.30 B.M. Electronic spectra of the formed complex appeared at two transition peaks on λ= 394 nm and 659 nm. The infrared spectra of the complex showed a shift of tertiary N-group absorption in 1234 and 1338 cm-1 compared to isonicotinic acid at 1149 and 1331 cm-1. In addition, the shift also appeared in the -OH group absorption which was to the lower wavenumber at 3371 cm-1 from 3425 cm-1 (isonicotinic acid). This fact indicated that the functional groups were coordinated to the central metal ion. The possibility formula of the complex was [Ni(asint)5(H2O)]SO4·3H2O with octahedral structure.

DFT calculations, spectroscopic, thermal analysis and biological activity of Sm(III) and Tb(III) complexes with 2-aminobenzoic and 2-amino-5-chloro-benzoic acids.

PubMed

Essawy, Amr A; Afifi, Manal A; Moustafa, H; El-Medani, S M

2014-10-15

The complexes of Sm(III) and Tb(III) with 2-aminobenzoic acid (anthranilic acid, AA) and 2-amino-5-chlorobenzoic acid (5-chloroanthranilic acid, AACl) were synthesized and characterized based on elemental analysis, IR and mass spectroscopy. The data are in accordance with 1:3 [Metal]:[Ligand] ratio. On the basis of the IR analysis, it was found that the metals were coordinated to bidentate anthranilic acid via the ionised oxygen of the carboxylate group and to the nitrogen of amino group. While in 5-chloroanthranilic acid, the metals were coordinated oxidatively to the bidentate carboxylate group without bonding to amino group; accordingly, a chlorine-affected coordination and reactivity-diversity was emphasized. Thermal analyses (TGA) and biological activity of the complexes were also investigated. Density Functional Theory (DFT) calculations at the B3LYP/6-311++G (d,p)_ level of theory have been carried out to investigate the equilibrium geometry of the ligand. The optimized geometry parameters of the complexes were evaluated using SDDALL basis set. Moreover, total energy, energy of HOMO and LUMO and Mullikan atomic charges were calculated. In addition, dipole moment and orientation have been performed and discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

DFT calculations, spectroscopic, thermal analysis and biological activity of Sm(III) and Tb(III) complexes with 2-aminobenzoic and 2-amino-5-chloro-benzoic acids

NASA Astrophysics Data System (ADS)

Essawy, Amr A.; Afifi, Manal A.; Moustafa, H.; El-Medani, S. M.

2014-10-01

The complexes of Sm(III) and Tb(III) with 2-aminobenzoic acid (anthranilic acid, AA) and 2-amino-5-chlorobenzoic acid (5-chloroanthranilic acid, AACl) were synthesized and characterized based on elemental analysis, IR and mass spectroscopy. The data are in accordance with 1:3 [Metal]:[Ligand] ratio. On the basis of the IR analysis, it was found that the metals were coordinated to bidentate anthranilic acid via the ionised oxygen of the carboxylate group and to the nitrogen of amino group. While in 5-chloroanthranilic acid, the metals were coordinated oxidatively to the bidentate carboxylate group without bonding to amino group; accordingly, a chlorine-affected coordination and reactivity-diversity was emphasized. Thermal analyses (TGA) and biological activity of the complexes were also investigated. Density Functional Theory (DFT) calculations at the B3LYP/6-311++G (d,p)_ level of theory have been carried out to investigate the equilibrium geometry of the ligand. The optimized geometry parameters of the complexes were evaluated using SDDALL basis set. Moreover, total energy, energy of HOMO and LUMO and Mullikan atomic charges were calculated. In addition, dipole moment and orientation have been performed and discussed.

Incorporation of Deoxyribonucleic Acid Precursors by T4 Deoxyribonucleic Acid-Protein Complexes Retained on Glass Fiber Filters

PubMed Central

Miller, Robert C.; Kozinski, Andrzej W.

1970-01-01

Bacteriophage T4 deoxyribonucleic acid (DNA)-protein complexes were retained preferentially on glass fiber filters. DNA polymerase activity in the complex was detected through the incorporation of 3H-labeled DNA precursors. The primer-product DNA hybridized with both phage and Escherichia coli DNA. Density labeling experiments showed that about 30% of incorporated 3H-deoxyadenosine triphosphate was found in DNA which hybridized with phage DNA; this DNA was found to be covalently attached to the primer DNA. PMID:5497903

The copper complexation ability of a synthetic humic-like acid formed by an abiotic humification process and the effect of experimental factors on its copper complexation ability.

PubMed

Yang, Ting; Hodson, Mark E

2018-03-26

Humic acids have an important impact on the distribution, toxicity, and bioavailability of hazardous metals in the environment. In this study, a synthetic humic-like acid (SHLA) was prepared by an abiotic humification process using catechol and glycine as humic precursors and a MnO 2 catalyst. The effect of physico-chemical conditions (ionic strength from 0.01 to 0.5 M NaNO 3 , pH from 4 to 8, temperature from 25 to 45 °C, and humic acid concentration from 5 to 100 mg/L) on the complexation ability of SHLA for Cu 2+ were investigated. A commercial humic acid (CHA, CAS: 1415-93-6) from Sigma-Aldrich was also studied for comparison. The results showed that for pH 4 to 8, the conditional stability constants (log K) of SHLA and CHA were in the range 5.63-8.62 and 4.87-6.23, respectively, and complexation capacities (CC) were 1.34-2.61 and 1.42-2.31 mmol/g, respectively. The Cu complexation ability of SHLA was higher than that of the CHA due to its higher number of acidic functional groups (SHLA 19.19 mmol/g; CHA 3.87 mmol/g), extent of humification and aromaticity (AL/AR: 0.333 (SHLA); 1.554 (CHA)), and O-alkyl functional groups (SHLA 15.56%; CHA 3.45%). The log K and complexation efficiency (fraction of metal bound to SHLA) of SHLA were higher at higher pH, lower ionic strength, higher temperature, and higher SHLA concentration. Overall, SHLA was a good and promising complexation agent for copper in both soil washing of copper contaminated soil and the treatment of copper-containing wastewater.

Luminescent and triboluminescent properties of europium(III) complex with cinnamic acid

NASA Astrophysics Data System (ADS)

Kalinovskaya, I. V.; Mirochnik, A. G.; Nagornyi, I. G.

2014-10-01

An intensely emitting crystalline europium(III) complex with cinnamic acid [Eu(Cin)3] n and exhibiting triboluminescent properties is synthesized. It is established that the measured photo- and triboluminescence spectra are identical for the above polymeric non-centrosymmetric complex and are determined by the characteristic f-f luminescence of the europium(III) ion.

Films prepared from poly(vinyl alcohol) and amylose-fatty acid salt inclusion complexes with increased surface hydrophobicity and high elongation

USDA-ARS?s Scientific Manuscript database

In this study, water-soluble amylose-inclusion complexes were prepared from high amylose corn starch and sodium salts of lauric, palmitic, and stearic acid by steam jet cooking. Cast films were prepared by combining the amylose complexes with poly(vinyl alcohol)(PVOH) solution at ratios varying from...

Spectroscopic studies on some fluorescent mixed-ligand titanium(IV) complexes.

PubMed

Baranwal, Balram Prasad; Singh, Alok Kumar; Varma, Anand

2011-12-15

A novel route to synthesize some titanium(IV) complexes containing acetylacetone, straight chain carboxylic acid and hydroxycarboxylic acid ligands has been investigated. Complexes with the general formula [Ti(acac)Cl(2-n)(OOCR*)(n)(OOCC(15)H(31))] (where Hacac=acetylacetone, R*COOH=hydroxycarboxylic acids and n=1 or 2) have been isolated and characterized. Molecular weight determinations indicated mononuclear nature of the complexes. LMCT bands were observed in the electronic spectra. Infrared spectra suggested bidentate nature of the ligands. Fluorescent behaviour of the complexes was noticed on the basis of fluorescence spectra. Powder XRD indicated them to be semi-crystalline having the crystallite size in 136-185 nm range. Transmission electron microscopy (TEM) indicated spherical particles of ~ 200 nm diameter. On the basis of physico-chemical studies, it is suggested that titanium is having coordination number 7 or 8 in these complexes. Copyright © 2011 Elsevier B.V. All rights reserved.

Clofibric acid stimulates branched-chain amino acid catabolism by three mechanisms.

PubMed

Kobayashi, Rumi; Murakami, Taro; Obayashi, Mariko; Nakai, Naoya; Jaskiewicz, Jerzy; Fujiwara, Yoko; Shimomura, Yoshiharu; Harris, Robert A

2002-11-15

Clofibrate promotes catabolism of branched-chain amino acids by increasing the activity of the branched-chain alpha-keto acid dehydrogenase [BCKDH] complex. Depending upon the sex of the rats, nutritional state, and tissue being studied, clofibrate can affect BCKDH complex activity by three different mechanisms. First, by directly inhibiting BCKDH kinase activity, clofibrate can increase the proportion of the BCKDH complex in the active, dephosphorylated state. This occurs in situations in which the BCKDH complex is largely inactive due to phosphorylation, e.g., in the skeletal muscle of chow-fed rats or in the liver of female rats late in the light cycle. Second, by increasing the levels at which the enzyme components of the BCKDH complex are expressed, clofibrate can increase the total enzymatic activity of the BCKDH complex. This is readily demonstrated in livers of rats fed a low-protein diet, a nutritional condition that induces a decrease in the level of expression of the BCKDH complex. Third, by decreasing the amount of BCKDH kinase expressed and therefore its activity, clofibrate induces an increase in the percentage of the BCKDH complex in the active, dephosphorylated state. This occurs in the livers of rats fed a low-protein diet, a nutritional condition that causes inactivation of the BCKDH complex due to upregulation of the amount of BCKDH kinase. WY-14,643, which, like clofibric acid, is a ligand for the peroxisome-proliferator-activated receptor alpha [PPARalpha], does not directly inhibit BCKDH kinase but produces the same long-term effects as clofibrate on expression of the BCKDH complex and its kinase. Thus, clofibrate is unique in its capacity to stimulate BCAA oxidation through inhibition of BCKDH kinase activity, whereas PPARalpha activators in general promote BCAA oxidation by increasing expression of components of the BCKDH complex and decreasing expression of the BCKDH kinase.

New bioactive silver(I) complexes: Synthesis, characterization, anticancer, antibacterial and anticarbonic anhydrase II activities

NASA Astrophysics Data System (ADS)

Ozdemir, Ummuhan O.; Ozbek, Neslihan; Genc, Zuhal Karagoz; İlbiz, Firdevs; Gündüzalp, Ayla Balaban

2017-06-01

Silver(I) complexes of alkyl sulfonic acide hydrazides were newly synthesized as homologous series. Methanesulfonic acide hydrazide (L1), ethanesulfonic acide hydrazide (L2), propanesulfonic acide hydrazide (L3) and butanesulfonic acide hydrazide (L4) were used for complexation with Ag(I) ions. The silver complexes obtained in the mol ratio of 1:2 have the structural formula as Ag(L1)2NO3 (I), Ag(L2)2NO3 (II), Ag(L3)2NO3(III), (Ag(L4)2NO3 (IV). The Ag(I) complexes exhibit distorted linear two-fold coordination in [AgL2]+ cations with uncoordinated nitrates. Ligands are chelated with silver(I) ions through unsubstituted primary nitrogen in hydrazide group. Ag(I) complexes were characterized by using elemental analysis, spectroscopic methods (FT-IR, LC-MS), magnetic susceptibility and conductivity measurements. Silver(I) complexes were optimized using PBEPBE/LanL2DZ/DEF2SV basic set performed by DFT method with the Gaussian 09 program package. The geometrical parameters, frontier molecular orbitals (HOMOs and LUMOs) and molecular electrostatic potential (MEP) mapped surfaces of the optimized geometries were also determined by this quantum set. The anticancer activities of silver(I) complexes on MCF-7 human breast cancer cell line were investigated by comparing IC50 values. The antibacterial activities of complexes were studied against Gram positive bacteria; S. aureus ATCC 6538, B. subtilis ATCC 6633, B. cereus NRRL-B-3711, E. faecalis ATCC 29212 and Gram negative bacteria; E. coli ATCC 11230, P. aeruginosa ATCC 15442, K. pneumonia ATCC 70063 by using disc diffusion method. The inhibition activities of Ag(I) complexes on carbonic anhydrase II enzyme (hCA II) were also investigated by comparing IC50 and Ki values. The biological activity screening shows that Ag(I) complex of butanesulfonicacidehydrazide (IV) has the highest activity against tested breast cancer cell lines MCF-7, Gram positive/Gram negative bacteria and carbonic anhydrase II (hCA II) isoenzyme.

Synthesis and characterization of a novel aminopolycarboxylate complexant for efficient trivalent f-element differentiation: N-butyl-2-acetamide-diethylenetriamine- N, N', N", N"-tetraacetic acid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heathman, Colt R.; Grimes, Travis S.; Jansone-Popova, Santa

The novel metal ion complexant N-butyl-2-acetamide-diethylenetriamine-N,N',N",N"-tetraacetic acid (DTTA-BuA) uses an amide functionalization to increase the total ligand acidity and attain efficient 4f/5f differentiation in low pH conditions. The amide, when located on the diethylenetriamine platform containing four acetate pendant arms maintains the octadentate coordination sphere for all investigated trivalent f-elements. This compact coordination environment inhibits the protonation of LnL- complexes, as indicated by lower K 111 constants relative to the corresponding protonation site of the free ligand. For actinide ions, the enhanced stability of AnL- lowers the K 111 for americium and curium beyond the aptitude of potentiometric detection. Densitymore » functional theory computations indicate the difference in the back-donation ability of Am 3+ and Eu 3+ f-orbitals is mainly responsible for stronger proton affinity of EuL- compared to AmL-. The measured stability constants for the formation of AmL- and CmL- complexes are consistently higher, relative to ML- complexes with lanthanides of similar charge density. When compared with the conventional aminopolycarboxylate diethylenetriamine pentaacetic acid (DTPA), the modified DTTA-BuA complexant features higher ligand acidity and the important An 3+/Ln 3+ differentiation when deployed on a liquid–liquid distribution platform.« less

Analysis of the Enhanced Stability of R(+)-Alpha Lipoic Acid by the Complex Formation with Cyclodextrins

PubMed Central

Ikuta, Naoko; Sugiyama, Hironori; Shimosegawa, Hiroshi; Nakane, Rie; Ishida, Yoshiyuki; Uekaji, Yukiko; Nakata, Daisuke; Pallauf, Kathrin; Rimbach, Gerald; Terao, Keiji; Matsugo, Seiichi

2013-01-01

R(+)-alpha lipoic acid (RALA) is one of the cofactors for mitochondrial enzymes and, therefore, plays a central role in energy metabolism. RALA is unstable when exposed to low pH or heat, and therefore, it is difficult to use enantiopure RALA as a pharma- and nutra-ceutical. In this study, we have aimed to stabilize RALA through complex formation with cyclodextrins (CDs). α-CD, β-CD and γ-CD were used for the formation of these RALA-CD complexes. We confirmed the complex formation using differential scanning calorimetry and showed by using HPLC analysis that complexed RALA is more stable than free RALA when subjected to humidity and high temperature or acidic pH conditions. Scanning electron microscopy studies showed that the particle size and shape differed depending on the cyclodextrin used for complexation. Further, the complexes of CD and RALA showed a different particle size distribution pattern compared with that of CD itself or that of the physical mixture of RALA and CD. PMID:23434662

Chemical and physical investigations on the charge transfer interaction of organic donors with iodine and its application as non-traditional organic conductors

NASA Astrophysics Data System (ADS)

Refat, Moamen S.; Sharshar, T.; Adam, Abdel Majid A.; Elsabawy, Khaled M.; Hemeda, O. M.

2014-09-01

The iso-leucine-iodide and methionine-iodide charge-transfer complexes were prepared and characterized using different spectroscopic techniques. The iodide charge-transfer complexes were synthesized by grinding KI-I2-amino acid with 1:1:1 M ratio in presence of few drops of methanol solvent. The structures of both solid amino acid iodide charge-transfer complexes are discussed with the help of the obtained results of the infrared and Raman laser spectra, Uv-vis. electronic spectra and thermal analyses. The electrical properties (AC resistivity and dielectric constant) of both complexes were investigated. The positron annihilation Doppler broadening (PADB) spectroscopies were also used to probe the structural changes of both complexes. The PADB line-shape parameters (S and W) were found to be dependent on the structure, electronic configuration of the charge transfer complex. The PADB technique is a powerful tool to probe the structural features of the KI-I2-amino acid complexes.

Initial hydrogenation during catabolism of picric acid by Rhodococcus erythropolis HL 24-2.

PubMed Central

Lenke, H; Knackmuss, H J

1992-01-01

Rhodococcus erythropolis HL 24-2, which was originally isolated as a 2,4-dinitrophenol-degrading bacterium, could also utilize picric acid as a nitrogen source after spontaneous mutation. During growth, the mutant HL PM-1 transiently accumulated an orange-red metabolite, which was identified as a hydride-Meisenheimer complex of picric acid. This complex was formed as the initial metabolite and further converted with concomitant liberation of nitrite. 2,4,6-Trinitrocyclohexanone was identified as a dead-end metabolite of the degradation of picric acid, indicating the addition of two hydride ions to picric acid. PMID:1444408

Recovery of organic acids

DOEpatents

Verser, Dan W.; Eggeman, Timothy J.

2009-10-13

A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

Recovery of organic acids

DOEpatents

Verser, Dan W [Menlo Park, CA; Eggeman, Timothy J [Lakewood, CO

2011-11-01

A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

Environmental Processing of Lipids Driven by Aqueous Photochemistry of α-Keto Acids

PubMed Central

2018-01-01

Sunlight can initiate photochemical reactions of organic molecules though direct photolysis, photosensitization, and indirect processes, often leading to complex radical chemistry that can increase molecular complexity in the environment. α-Keto acids act as photoinitiators for organic species that are not themselves photoactive. Here, we demonstrate this capability through the reaction of two α-keto acids, pyruvic acid and 2-oxooctanoic acid, with a series of fatty acids and fatty alcohols. We show for five different cases that a cross-product between the photoinitiated α-keto acid and non-photoactive species is formed during photolysis in aqueous solution. Fatty acids and alcohols are relatively unreactive species, which suggests that α-keto acids are able to act as radical initiators for many atmospherically relevant molecules found in the sea surface microlayer and on atmospheric aerosol particles. PMID:29806009

Conversion of Arylboronic Acids to Tetrazoles Catalyzed by ONO Pincer-Type Palladium Complex.

PubMed

Vignesh, Arumugam; Bhuvanesh, Nattamai S P; Dharmaraj, Nallasamy

2017-01-20

A convenient synthesis of a library of tetrazoles through a novel and operationally simple protocol effecting the direct conversion of arylboronic acids catalyzed by a new ONO pincer-type Pd(II) complex under mild reaction conditions using the readily available reagents is reported. The palladium complex was reused up to four cycles in an open-flask condition.

The mechanism of interaction of polymethacrylic acid with sodium dodecylbenzenesulfonate in aqueous solutions

NASA Astrophysics Data System (ADS)

Sachko, A. V.; Zakordonskii, V. P.; Voloshinovskii, A. S.; Golod, T. Yu.

2009-07-01

A complex of physicochemical methods (light scattering, potentiometry, conductometry, viscometry, tensiometry, and fluorescence spectroscopy) were used to show the possibility of formation of intermolecular associates/complexes in systems with likely charged components. The driving forces of such interactions were analyzed and a possible scheme of complex formation between polymethacrylic acid and sodium dodecylbenzenesulfonate was suggested.

Antibacterial characteristics of newly developed amphiphilic lipids and DNA-lipid complexes against bacteria.

PubMed

Inoue, Y; Fukushima, T; Hayakawa, T; Takeuchi, H; Kaminishi, H; Miyazaki, K; Okahata, Y

2003-05-01

The purpose of this study was to investigate the antibacterial activity of newly developed amphiphilic lipids and DNA/lipid complexes against two types of oral bacteria and two types of hospital infection bacteria. Nine amphiphilic lipids were quantitatively prepared from the reaction of n-alkyl alcohol, alpha-amino acids, and p-toluenesulfonic acid. Nine DNA-lipid complexes were prepared by the simple mixing of DNA and amphiphilic lipids. The DNA-lipid complexes were insoluble in water. The antibacterial activity of lipids and DNA-lipid complexes against Porphyromonas gingivalis, Streptococcus mutans, Staphylococcus aureus, and Pseudomonas aeruginosa were evaluated by the disk-diffusion method. Seven artificial lipids showed antibacterial behavior; in particular, the lipids prepared from n-decyl alcohol and glycine and from n-decyl alcohol and L-alanine showed antibacterial activity against the four bacterial strains used in this study. On the other hand, the lipids of glutamic acid derivatives did not show any antibacterial activity against the four bacteria strains except for the lipid with an n-octyl group. Five DNA-lipid complexes also had an antibacterial effect. The complex prepared from DNA and glycine decyl ester p-toluenesulfonic acid salt exhibited antibacterial activity against the four types of bacteria strains. In this study it was found that lipids and DNA-lipid complexes with a mono-decyl group or a mono-dodecyl group have more favorable antibacterial activity. Copyright 2003 Wiley Periodicals, Inc.

New Insights Into the Mechanisms and Biological Roles of D-Amino Acids in Complex Eco-Systems

PubMed Central

Aliashkevich, Alena; Alvarez, Laura; Cava, Felipe

2018-01-01

In the environment bacteria share their habitat with a great diversity of organisms, from microbes to humans, animals and plants. In these complex communities, the production of extracellular effectors is a common strategy to control the biodiversity by interfering with the growth and/or viability of nearby microbes. One of such effectors relies on the production and release of extracellular D-amino acids which regulate diverse cellular processes such as cell wall biogenesis, biofilm integrity, and spore germination. Non-canonical D-amino acids are mainly produced by broad spectrum racemases (Bsr). Bsr’s promiscuity allows it to generate high concentrations of D-amino acids in environments with variable compositions of L-amino acids. However, it was not clear until recent whether these molecules exhibit divergent functions. Here we review the distinctive biological roles of D-amino acids, their mechanisms of action and their modulatory properties of the biodiversity of complex eco-systems. PMID:29681896

Preparation and spectroscopic studies on charge-transfer complexes of 2,2'-bipyridine with picric and chloranilic acids

NASA Astrophysics Data System (ADS)

Teleb, Said M.; Gaballa, Akmal S.

2005-11-01

Charge-transfer (CT) complexes formed on the reaction of 2,2'-bipyridine with some acceptors such as picric acid (HPA) and chloranilic acid (H 2CA) have been studied in CHCl 3 and MeOH at room temperature. Based on elemental analysis and IR spectra of the solid CT complexes along with the photometric titration curves for the reactions, the data obtained indicate the formation of 1:1 charge-transfer complexes [(bpyH)(PA)] and [(bpyH 2)(CA)], respectively. The infrared and 1H NMR spectroscopic data indicate a charge-transfer interaction associated with a proton migration from the acceptor to the donor followed by intramolecular hydrogen bonding. The formation constants ( KC) for the complexes were shown to be dependent on the structure of the electron acceptors used.

Preparation and spectroscopic studies on charge-transfer complexes of 2,2'-bipyridine with picric and chloranilic acids.

PubMed

Teleb, Said M; Gaballa, Akmal S

2005-11-01

Charge-transfer (CT) complexes formed on the reaction of 2,2'-bipyridine with some acceptors such as picric acid (HPA) and chloranilic acid (H(2)CA) have been studied in CHCl(3) and MeOH at room temperature. Based on elemental analysis and IR spectra of the solid CT complexes along with the photometric titration curves for the reactions, the data obtained indicate the formation of 1:1 charge-transfer complexes [(bpyH)(PA)] and [(bpyH(2))(CA)], respectively. The infrared and (1)H NMR spectroscopic data indicate a charge-transfer interaction associated with a proton migration from the acceptor to the donor followed by intramolecular hydrogen bonding. The formation constants (K(C)) for the complexes were shown to be dependent on the structure of the electron acceptors used.

Fe-tannic acid complex dye as photo sensitizer for different morphological ZnO based DSSCs

NASA Astrophysics Data System (ADS)

Çakar, Soner; Özacar, Mahmut

2016-06-01

In this paper we have synthesized different morphological ZnO nanostructures via microwave hydrothermal methods at low temperature within a short time. We described different morphologies of ZnO at different Zn(NO3)2/KOH mole ratio. The ZnO nanostructures were characterized via X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and UV-vis spectrophotometry. All ZnO structures have hexagonal wurtzite type structures. The FESEM images showed various morphologies of ZnO such as plate, rod and nanoparticles. Dye sensitized solar cells have been assembled by these different morphological structures photo electrode and tannic acid or Fe-tannic acid complex dye as sensitizer. We have achieved at maximum efficiencies of photovoltaic cells prepared with ZnO plate in all dye systems. The conversion efficiencies of dye sensitized solar cells are 0.37% and 1.00% with tannic acid and Fe-tannic acid complex dye, respectively.

Electronic structure and acid-base properties of Kojic acid and its dimers. A DFT and quantum topology study

NASA Astrophysics Data System (ADS)

Aziz, Saadullah G.; Alyoubi, Abdulrahman O.; Elroby, Shaaban A.; Hilal, Rifaat H.

2017-10-01

Kojic acid is a polyfunctional heterocyclic compound, with several important reaction centres; it has a wide range of applications in the cosmetic, medicine, food, agriculture and chemical industries. The present study aims at better insight into its electronic structure and bonding characteristics. Thus, density functional theory at the M06-2x /6-311++G** level of theory is used to investigate its ground state electronic and acid-base properties. Protonation and deprotonation enthalpies are computed and analysed. The ability of Kojic acid to form both water complexes and dimers is explored. Several different complexes and dimer structures were examined. Natural bond order and quantum topology features of the charge density were analysed. The origin of the stability of the studied complexes and dimer structures can be traced to hydrogen bonding, π-conjugative and non-covalent dispersive interactions.

Metal-organic complexes in geochemical processes: Estimation of standard partial molal thermodynamic properties of aqueous complexes between metal cations and monovalent organic acid ligands at high pressures and temperatures

NASA Astrophysics Data System (ADS)

Shock, Everetr L.; Koretsky, Carla M.

1995-04-01

Regression of standard state equilibrium constants with the revised Helgeson-Kirkham-Flowers (HKF) equation of state allows evaluation of standard partial molal entropies ( overlineSo) of aqueous metal-organic complexes involving monovalent organic acid ligands. These values of overlineSo provide the basis for correlations that can be used, together with correlation algorithms among standard partial molal properties of aqueous complexes and equation-of-state parameters, to estimate thermodynamic properties including equilibrium constants for complexes between aqueous metals and several monovalent organic acid ligands at the elevated pressures and temperatures of many geochemical processes which involve aqueous solutions. Data, parameters, and estimates are given for 270 formate, propanoate, n-butanoate, n-pentanoate, glycolate, lactate, glycinate, and alanate complexes, and a consistent algorithm is provided for making other estimates. Standard partial molal entropies of association ( Δ -Sro) for metal-monovalent organic acid ligand complexes fall into at least two groups dependent upon the type of functional groups present in the ligand. It is shown that isothermal correlations among equilibrium constants for complex formation are consistent with one another and with similar correlations for inorganic metal-ligand complexes. Additional correlations allow estimates of standard partial molal Gibbs free energies of association at 25°C and 1 bar which can be used in cases where no experimentally derived values are available.

Mitoregulin: A lncRNA-Encoded Microprotein that Supports Mitochondrial Supercomplexes and Respiratory Efficiency.

PubMed

Stein, Colleen S; Jadiya, Pooja; Zhang, Xiaoming; McLendon, Jared M; Abouassaly, Gabrielle M; Witmer, Nathan H; Anderson, Ethan J; Elrod, John W; Boudreau, Ryan L

2018-06-26

Mitochondria are composed of many small proteins that control protein synthesis, complex assembly, metabolism, and ion and reactive oxygen species (ROS) handling. We show that a skeletal muscle- and heart-enriched long non-coding RNA, LINC00116, encodes a highly conserved 56-amino-acid microprotein that we named mitoregulin (Mtln). Mtln localizes to the inner mitochondrial membrane, where it binds cardiolipin and influences protein complex assembly. In cultured cells, Mtln overexpression increases mitochondrial membrane potential, respiration rates, and Ca 2+ retention capacity while decreasing mitochondrial ROS and matrix-free Ca 2+ . Mtln-knockout mice display perturbations in mitochondrial respiratory (super)complex formation and activity, fatty acid oxidation, tricarboxylic acid (TCA) cycle enzymes, and Ca 2+ retention capacity. Blue-native gel electrophoresis revealed that Mtln co-migrates alongside several complexes, including the complex I assembly module, complex V, and supercomplexes. Under denaturing conditions, Mtln remains in high-molecular-weight complexes, supporting its role as a sticky molecular tether that enhances respiratory efficiency by bolstering protein complex assembly and/or stability. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Photocatalytic CO2 reduction with high turnover frequency and selectivity of formic acid formation using Ru(II) multinuclear complexes

PubMed Central

Tamaki, Yusuke; Morimoto, Tatsuki; Koike, Kazuhide; Ishitani, Osamu

2012-01-01

Previously undescribed supramolecules constructed with various ratios of two kinds of Ru(II) complexes—a photosensitizer and a catalyst—were synthesized. These complexes can photocatalyze the reduction of CO2 to formic acid with high selectivity and durability using a wide range of wavelengths of visible light and NADH model compounds as electron donors in a mixed solution of dimethylformamide–triethanolamine. Using a higher ratio of the photosensitizer unit to the catalyst unit led to a higher yield of formic acid. In particular, of the reported photocatalysts, a trinuclear complex with two photosensitizer units and one catalyst unit photocatalyzed CO2 reduction (ΦHCOOH = 0.061, TONHCOOH = 671) with the fastest reaction rate (TOFHCOOH = 11.6 min-1). On the other hand, photocatalyses of a mixed system containing two kinds of model mononuclear Ru(II) complexes, and supramolecules with a higher ratio of the catalyst unit were much less efficient, and black oligomers and polymers were produced from the Ru complexes during photocatalytic reactions, which reduced the yield of formic acid. The photocatalytic formation of formic acid using the supramolecules described herein proceeds via two sequential processes: the photochemical reduction of the photosensitizer unit by NADH model compounds and intramolecular electron transfer to the catalyst unit. PMID:22908243

NMR studies of protein-nucleic acid interactions.

PubMed

Varani, Gabriele; Chen, Yu; Leeper, Thomas C

2004-01-01

Protein-DNA and protein-RNA complexes play key functional roles in every living organism. Therefore, the elucidation of their structure and dynamics is an important goal of structural and molecular biology. Nuclear magnetic resonance (NMR) studies of protein and nucleic acid complexes have common features with studies of protein-protein complexes: the interaction surfaces between the molecules must be carefully delineated, the relative orientation of the two species needs to be accurately and precisely determined, and close intermolecular contacts defined by nuclear Overhauser effects (NOEs) must be obtained. However, differences in NMR properties (e.g., chemical shifts) and biosynthetic pathways for sample productions generate important differences. Chemical shift differences between the protein and nucleic acid resonances can aid the NMR structure determination process; however, the relatively limited dispersion of the RNA ribose resonances makes the process of assigning intermolecular NOEs more difficult. The analysis of the resulting structures requires computational tools unique to nucleic acid interactions. This chapter summarizes the most important elements of the structure determination by NMR of protein-nucleic acid complexes and their analysis. The main emphasis is on recent developments (e.g., residual dipolar couplings and new Web-based analysis tools) that have facilitated NMR studies of these complexes and expanded the type of biological problems to which NMR techniques of structural elucidation can now be applied.

Experimental and Theoretical Investigations of Infrared Multiple Photon Dissociation Spectra of Aspartic Acid Complexes with Zn2+ and Cd2.

PubMed

Boles, Georgia C; Hightower, Randy L; Coates, Rebecca A; McNary, Christopher P; Berden, Giel; Oomens, Jos; Armentrout, P B

2018-04-12

Complexes of aspartic acid (Asp) cationized with Zn 2+ : Zn(Asp-H) + , Zn(Asp-H) + (ACN) where ACN = acetonitrile, and Zn(Asp-H) + (Asp); as well as with Cd 2+ , CdCl + (Asp), were examined by infrared multiple photon dissociation (IRMPD) action spectroscopy using light generated from a free electron laser. A series of low-energy conformers for each complex was found using quantum chemical calculations to identify the structures formed experimentally. The main binding motif observed for the heavy-metal complex, CdCl + (Asp)[N,CO,CO s ], is a charge-solvated, tridentate structure, where the metal center binds to the backbone amino group and carbonyl oxygens of the backbone and side-chain carboxylic acids. Likewise, the deprotonated Zn(Asp-H) + (ACN) and Zn(Asp-H) + (Asp) complexes show comparable [N,CO - ,CO s ](ACN) and [N,CO - ,CO s ][N,CO,CO s ] coordinations, respectively. Interestingly, there was only minor spectral evidence for the analogous Zn(Asp-H) + [N,CO - ,CO s ] binding motif, even though this species is predicted to be the lowest-energy conformer. Instead, rearrangement and partial dissociation of the amino acid are observed, as spectral features most consistent with the experimental spectrum are exhibited by a four-coordinate Zn(Asp-NH 4 ) + [CO 2 - ,CO s ](NH 3 ) complex. Analysis of the mechanistic pathway leading from the predicted lowest-energy conformer to the isobaric deaminated complex is explored theoretically. Further, comparison of the current work to that of Zn 2+ and Cd 2+ complexes of asparagine (Asn) allows additional conclusions regarding populated conformers and effects of carboxamide versus carboxylic acid binding to be drawn.

Proton transfer complexes based on some π-acceptors having acidic protons with 3-amino-6-[2-(2-thienyl)vinyl]-1,2,4-triazin-5(4 H)-one donor: Synthesis and spectroscopic characterizations

NASA Astrophysics Data System (ADS)

Refat, Moamen S.; Saad, Hosam A.; Adam, Abdel Majid A.

2011-05-01

Charge transfer complexes based on 3-amino-6-[2-(2-thienyl)vinyl]-1,2,4-triazin-5(4 H)-one (ArNH 2) organic basic donor and pi-acceptors having acidic protons such as picric acid (PiA), hydroquinone (Q(OH) 2) and 3,5-dinitrobenzene (DNB) have been synthesized and spectroscopically studied. The sbnd NH3+ ammonium ion was formed under the acid-base theory through proton transfer from an acidic to basic centers in all charge transfer complexes resulted. The values of formation constant ( KCT) and molar extinction coefficient ( ɛCT) which were estimated from the spectrophotometric studies have a dramatic effect for the charge transfer complexes with differentiation of pi-acceptors. For further studies the vibrational spectroscopy of the [( ArNH3+)(PiA -)] (1), [( ArNH3+)(Q (OH)2-)] (2) and [( ArNH3+)(DNB -)] (3) of (1:1) charge transfer complexes of (donor: acceptor) were characterized by elemental analysis, infrared spectra, Raman spectra, 1H and 13CNMR spectra. The experimental data of elemental analyses of the charge transfer complexes (1), (2) and (3) were in agreement with calculated data. The IR and Raman spectra of (1), (2) and (3) are indicated to the presence of bands around 3100 and 1600 cm -1 distinguish to sbnd NH3+. The thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) techniques were performed to give knowledge about thermal stability behavior of the synthesized charge transfer complexes. The morphological features of start materials and charge transfer complexes were investigated using scanning electron microscopy (SEM) and optical microscopy.

The presence of lead decreases the availability of meso-2, 3-dimercaptosuccinic acid for analysis in the monobromobimane assay.

PubMed

Lever, S Z; Parsons, T L

1999-11-01

meso-2,3-Dimercaptosuccinic acid is a suitable chelating agent for routine pharmacotherapy of lead poisoning in children. Administration of meso-2,3-dimercaptosuccinic acid presumably permits complexation of lead in vivo, allowing excretion through urine or feces. Quantification of the lead is achieved independently from the analysis of meso-2,3-dimercaptosuccinic acid and metabolites from the monobromobimane assay. To date, no direct chemical characterization of the Pb species excreted in urine has been successful. Pharmacokinetic correlation of lead excretion with excretion of meso-2,3-dimercaptosuccinic acid and metabolites has been utilized as an indirect method to draw conclusions regarding the identity of the active chelating agent. In this study, we hypothesized that the Pb-coordinated thiols are not reactive with respect to monobromobimane, and thus, the active chelator contained in the lead complex escapes detection. We performed variations of the assay and found that (1) the fluorescence detector response for the meso-2,3-dimercaptosuccinic acid-monobromobimane adduct was clearly attenuated as a function of added Pb, (2) when meso-2, 3-dimercaptosuccinic acid and monobromobimane were mixed prior to the addition of lead, the lead had no effect on detector response, (3) the addition of dithiothreitol does not affect the ability of Pb to react with meso-2,3-dimercaptosuccinic acid and verifies that oxidation of meso-DMSA had not occurred, and (4) the addition of ethylenediaminetetraacetic acid to the assay reverses the result found in point 1, presumably through trans chelation of the Pb-DMSA complex. Indirect quantification of the Pb-DMSA complexes found in urine might be accomplished through modification of the standard monobromobimane assay for analysis of meso-2,3-dimercaptosuccinic acid.

Screening selves: sciences of memory and identity on film, 1930-1960.

PubMed

Winter, Alison

2004-11-01

Chemicals that could be used scientifically to force an individual to tell the truth - dubbed truth sera - were first described in the early 1920s. Ever since, the notion of "truth drugs" has remained tenaciously within popular culture. One of the most important reasons for the survival of the notion of a pharmaceutical technology of authenticity was the role of the barbiturates sodium amytal and sodium pentothal in psychiatric research and treatment during the 1930s through the 1950s. This article traces that history, giving special emphasis to the role of motion pictures. The article argues that researchers were seeking to develop a technology of authenticity (rather than of the truth per se). It examines how they used motion pictures to help them develop and disseminate this technology.

Peter Bourne's drug policy and the perils of a public health ethic, 1976-1978.

PubMed

Clark, Claire D; Dufton, Emily

2015-02-01

As President Jimmy Carter's advisor for health issues, Peter Bourne promoted a rational and comprehensive drug strategy that combined new supply-side efforts to prevent drug use with previously established demand-side addiction treatment programs. Using a public health ethic that allowed the impact of substances on overall population health to guide drug control, Bourne advocated for marijuana decriminalization as well as increased regulations for barbiturates. A hostile political climate, a series of rumors, and pressure from both drug legalizers and prohibitionists caused Bourne to resign in disgrace in 1978. We argue that Bourne's critics used his own public health framework to challenge him, describe the health critiques that contributed to Bourne's resignation, and present the story of his departure as a cautionary tale for today's drug policy reformers.

Central nervous system side effects associated with zolpidem treatment.

PubMed

Toner, L C; Tsambiras, B M; Catalano, G; Catalano, M C; Cooper, D S

2000-01-01

Zolpidem is one of the newer medications developed for the treatment of insomnia. It is an imidazopyridine agent that is an alternative to the typical sedative-hypnotic agents. Zolpidem use is gaining favor because of its efficacy and its side effect profile, which is milder and less problematic than that of the benzodiazepines and barbiturates used to treat insomnia. Still, side effects are not uncommon with zolpidem use. We report a series of cases in which the patients developed delirium, nightmares and hallucinations during treatment with zolpidem. We will review its pharmacology, discuss previous reports of central nervous system side effects, examine the impact of drug interactions with concurrent use of antidepressants, examine gender differences in susceptibility to side effects, and explore the significance of protein binding in producing side effects.

Devices, systems, and methods for detecting nucleic acids using sedimentation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koh, Chung-Yan; Schaff, Ulrich Y.; Sommer, Gregory J.

Embodiments of the present invention are directed toward devices, systems, and method for conducting nucleic acid purification and quantification using sedimentation. In one example, a method includes generating complexes which bind to a plurality of beads in a fluid sample, individual ones of the complexes comprising a nucleic acid molecule such as DNA or RNA and a labeling agent. The plurality of beads including the complexes may be transported through a density media, wherein the density media has a density lower than a density of the beads and higher than a density of the fluid sample, and wherein the transportingmore » occurs, at least in part, by sedimentation. Signal may be detected from the labeling agents of the complexes.« less

Intracellular processing of poly(ethylene imine)/ribozyme complexes can be observed in living cells by using confocal laser scanning microscopy and inhibitor experiments.

PubMed

Merdan, Thomas; Kunath, Klaus; Fischer, Dagmar; Kopecek, Jindrich; Kissel, Thomas

2002-02-01

Critical steps in the subcellular processing of poly(ethylene imine)/nucleic acid complexes, especially endosomal/lysosomal escape, were visualized by using living cell confocal laser scanning microscopy (CSLM) to obtain an insight into their mechanism. Living cell confocal microscopy was used to examine the intracellular fate of poly(ethylene imine)/ribozyme and poly(L-lysine)/ribozyme complexes over time, in the presence of and without bafilomycin Al, a selective inhibitor of endosomal/lysosomal acidification. The compartment of complex accumulation was identified by confocal microscopy with a fluorescent acidotropic dye. To confirm microscopic data, luciferase reporter gene expression was determined under similar experimental conditions. Poly(ethylene imine)/ribozyme complexes accumulate in acidic vesicles, most probably lysosomes. Release of complexes occurs in a sudden event, very likely due to bursting of these organelles. After release, poly(ethylene imine) and ribozyme spread throughout the cell, during which slight differences in distribution between cytosol and nucleus are visible. No lysosomal escape was observed with poly(L-lysine)/ribozyme complexes or when poly(ethylene imine)/ ribozyme complexes were applied together with bafilomycin A1. Poly(ethylene imine)/plasmid complexes exhibited a high luciferase expression, which was reduced approximately 200-fold when lysosomal acidification was suppressed with bafilomycin A1. Our data provide, for the first time, direct experimental evidence for the escape of poly(ethylene imine)/nucleic acid complexes from the endosomal/lysosomal compartment. CLSM, in conjunction with living cell microscopy, is a promising tool for studying the subcellular fate of polyplexes in nucleic acid/gene delivery.

The HIV antiretroviral drug efavirenz has LSD-like properties.

PubMed

Gatch, Michael B; Kozlenkov, Alexey; Huang, Ren-Qi; Yang, Wenjuan; Nguyen, Jacques D; González-Maeso, Javier; Rice, Kenner C; France, Charles P; Dillon, Glenn H; Forster, Michael J; Schetz, John A

2013-11-01

Anecdotal reports have surfaced concerning misuse of the HIV antiretroviral medication efavirenz ((4S)-6-chloro-4-(2-cyclopropylethynyl)-4-(trifluoromethyl)-2,4-dihydro-1H-3,1-benzoxazin-2-one) by HIV patients and non-infected teens who crush the pills and smoke the powder for its psychoactive effects. Molecular profiling of the receptor pharmacology of efavirenz pinpointed interactions with multiple established sites of action for other known drugs of abuse including catecholamine and indolamine transporters, and GABAA and 5-HT(2A) receptors. In rodents, interaction with the 5-HT(2A) receptor, a primary site of action of lysergic acid diethylamine (LSD), appears to dominate efavirenz's behavioral profile. Both LSD and efavirenz reduce ambulation in a novel open-field environment. Efavirenz occasions drug-lever responding in rats discriminating LSD from saline, and this effect is abolished by selective blockade of the 5-HT(2A) receptor. Similar to LSD, efavirenz induces head-twitch responses in wild-type, but not in 5-HT(2A)-knockout, mice. Despite having GABAA-potentiating effects (like benzodiazepines and barbiturates), and interactions with dopamine transporter, serotonin transporter, and vesicular monoamine transporter 2 (like cocaine and methamphetamine), efavirenz fails to maintain responding in rats that self-administer cocaine, and it fails to produce a conditioned place preference. Although its molecular pharmacology is multifarious, efavirenz's prevailing behavioral effect in rodents is consistent with LSD-like activity mediated via the 5-HT(2A) receptor. This finding correlates, in part, with the subjective experiences in humans who abuse efavirenz and with specific dose-dependent adverse neuropsychiatric events, such as hallucinations and night terrors, reported by HIV patients taking it as a medication.

The HIV Antiretroviral Drug Efavirenz has LSD-Like Properties

PubMed Central

Gatch, Michael B; Kozlenkov, Alexey; Huang, Ren-Qi; Yang, Wenjuan; Nguyen, Jacques D; González-Maeso, Javier; Rice, Kenner C; France, Charles P; Dillon, Glenn H; Forster, Michael J; Schetz, John A

2013-01-01

Anecdotal reports have surfaced concerning misuse of the HIV antiretroviral medication efavirenz ((4S)-6-chloro-4-(2-cyclopropylethynyl)-4-(trifluoromethyl)-2,4-dihydro-1H-3,1-benzoxazin-2-one) by HIV patients and non-infected teens who crush the pills and smoke the powder for its psychoactive effects. Molecular profiling of the receptor pharmacology of efavirenz pinpointed interactions with multiple established sites of action for other known drugs of abuse including catecholamine and indolamine transporters, and GABAA and 5-HT2A receptors. In rodents, interaction with the 5-HT2A receptor, a primary site of action of lysergic acid diethylamine (LSD), appears to dominate efavirenz's behavioral profile. Both LSD and efavirenz reduce ambulation in a novel open-field environment. Efavirenz occasions drug-lever responding in rats discriminating LSD from saline, and this effect is abolished by selective blockade of the 5-HT2A receptor. Similar to LSD, efavirenz induces head-twitch responses in wild-type, but not in 5-HT2A-knockout, mice. Despite having GABAA-potentiating effects (like benzodiazepines and barbiturates), and interactions with dopamine transporter, serotonin transporter, and vesicular monoamine transporter 2 (like cocaine and methamphetamine), efavirenz fails to maintain responding in rats that self-administer cocaine, and it fails to produce a conditioned place preference. Although its molecular pharmacology is multifarious, efavirenz's prevailing behavioral effect in rodents is consistent with LSD-like activity mediated via the 5-HT2A receptor. This finding correlates, in part, with the subjective experiences in humans who abuse efavirenz and with specific dose-dependent adverse neuropsychiatric events, such as hallucinations and night terrors, reported by HIV patients taking it as a medication. PMID:23702798

High-temperature solid-phase microextraction procedure for the detection of drugs by gas chromatography-mass spectrometry.

PubMed

Staerk, U; Külpmann, W R

2000-08-18

High-temperature headspace solid-phase microextraction (SPME) with simultaneous ("in situ") derivatisation (acetylation or silylation) is a new sample preparation technique for the screening of illicit drugs in urine and for the confirmation analysis in serum by GC-MS. After extraction of urine with a small portion of an organic solvent mixture (e.g., 2 ml of hexane-ethyl acetate) at pH 9, the organic layer is separated and evaporated to dryness in a small headspace vial. A SPME-fiber (e.g., polyacrylate) doped with acetic anhydride-pyridine (for acetylation) is exposed to the vapour phase for 10 min at 200 degrees C in a blockheater. The SPME fiber is then injected into the GC-MS for thermal desorption and analysis. After addition of perchloric acid and extraction with n-hexane to remove lipids, the serum can be analysed after adjusting to pH 9 as described for urine. Very clean extracts are obtained. The various drugs investigated could be detected and identified in urine by the total ion current technique at the following concentrations: amphetamines (200 microg/l), barbiturates (500 microg/l), benzodiazepines (100 microg/l), benzoylecgonine (150 microg/l), methadone (100 microg/l) and opiates (200 microg/l). In serum all drugs could be detected by the selected ion monitoring technique within their therapeutic range. As compared to liquid-liquid extraction only small amounts of organic solvent are needed and larger amounts of the pertinent analytes could be transferred to the GC column. In contrast to solid-phase extraction (SPE), the SPME-fiber is reusable several times (as there is no contamination by endogenous compounds). The method is time-saving and can be mechanised by the use of a dedicated autosampler.

The pharmaceutical industry and the German National Socialist Regime: I.G. Farben and pharmacological research.

PubMed

López-Muñoz, F; García-García, P; Alamo, C

2009-02-01

Before the National Socialist party came to power, the German pharmaceutical industry constituted an international reference as far as the development of new medicines was concerned, having been responsible for synthetic analgesics (phenacetin, phenazones, acetylsalicylic acid), arsphenamine, barbiturates and sulfonamides. The year 1925 saw the founding of I.G. Farben (Interessen-Gemeinschaft Farbenindustrie AG), a conglomerate of companies that would monopolize the country's chemical production and come to own all its major pharmaceutical industries. During the World War II, I.G. Farben participated in numerous operations associated with the criminal activities of the Nazi executive, including the use of slave labour in plants built close to concentration camps, such as that at Auschwitz. With regard to medical and pharmacological research projects, I.G. Farben became involved in experimental programmes using patients from the Nazi regime's euthanasia programmes and healthy subjects recruited without their consent from concentration camps, on whom various pharmacological substances were tested, including sulfamide and arsenical derivatives and other preparations whose composition is not precisely known (B-1012, B-1034, 3382 or Rutenol, 3582 or Acridine), generally in relation to the treatment of infectious diseases, such as typhus, erysipelas, scarlet fever or paratyphoid diarrhoea. Furthermore, I.G. Farben played a decisive role in the German army's chemical warfare programme, contributing to the development of the first two neurotoxic substances, later known as 'nerve agents', tabun and sarin. Some of these activities came to light as a result of the one the famous Nuremberg Trials in 1947, which saw 24 executives and scientists from I.G. Farben brought to justice for, among other offences, the use of slave labour in the concentration camps and forced experimentation with drugs on prisoners.

Differential Effects of Low-Molecular-Weight Organic Acids on the Mobilization of Soil-Borne Arsenic and Trace Metals.

PubMed

Nworie, Obinna Elijah; Qin, Junhao; Lin, Chuxia

2017-08-21

A batch experiment was conducted to examine the effects of six low-molecular-weight organic acids on the mobilization of arsenic and trace metals from a range of contaminated soils. The results showed that the organic acids behaved differently when reacting with soil-borne As and trace metals. Oxalic acid and acetic acid had the strongest and weakest capacity to mobilize the investigated elements, respectively. The solubilisation of iron oxides by the organic acids appears to play a critical role in mobilizing other trace metals and As. Apart from acidification and complexation, reductive dissolution played a dominant role in the dissolution of iron oxides in the presence of oxalic acid, while acidification tended to be more important for dissolving iron oxides in the presence of other organic acids. The unique capacity of oxalic acid to solubilize iron oxides tended to affect the mobilization of other elements in different ways. For Cu, Mn, and Zn, acidification-driven mobilization was likely to be dominant while complexation might play a major role in Pb mobilization. The formation of soluble Fe and Pb oxalate complexes could effectively prevent arsenate or arsenite from combining with these metals to form solid phases of Fe or Pb arsenate or arsenite.

Electronic effects on the catalytic disproportionation of formic acid to methanol by [Cp*Ir(III)(R-bpy)Cl]Cl complexes.

PubMed

Sasayama, A F; Moore, C E; Kubiak, C P

2016-02-14

A series of [Cp*Ir(III)(R-bpy)Cl]Cl (R-bpy = 4,4'-di-R-2,2'-bipyridine; R = CF3, H, Me, tBu, OMe) complexes was prepared and studied for catalytic formic acid disproportionation. The relationship between the electron donating strength of the bipyridine substituents and methanol production of the corresponding complexes was analyzed; the unsubstituted (R = H) complex was the most selective for methanol formation.

RECOVERY OF URANIUM BY SECONDARY XANTHATE COMPLEXING

DOEpatents

Neville, O.K.

1959-09-01

A method is described for separating and recovering uranium values contained in an acidic aqueous solution together with thorium or protactinium values. In accordance with the invention, the acidic solution containing uranium in the uranyl form is contacted with an organic xanthate. The xanthate forms a urano-xanthate complex but is substantially non-reactive with thorium and protactinium. The urano-xanthate complex is recovered by organic solvent extraction.

Characterization of the Unusual Product from the Reaction between Cobalt(II) Chloride, Ethane-1,2-diamine, and Hydrochloric Acid: An Undergraduate Project Involving an Unknown Metal Complex.

ERIC Educational Resources Information Center

Curtis, Neil F.; And Others

1986-01-01

Discusses the need for student research-type chemistry projects based upon "unknown" metal complexes. Describes an experiment involving the product from the reaction between cobalt(II) chloride, ethane-1,2-diamine (en) and concentrated hydrochloric acid. Outlines the preparation of the cobalt complex, along with procedure, results and…

Electrospun polymer nanofibers reinforced by tannic acid/Fe+++ complexes

USDA-ARS?s Scientific Manuscript database

Nanofibers and fibrous mats of polyvinyl alcohol (PVA) loaded with tannic acid (TA) and ferric ion (Fe+++) complexes (TA-Fe+++) were synthesized by the electrospinning technique. The spinning solutions were characterized for surface tension, electrical conductivity, and viscosity. It was found that ...

Simultaneous determination of thermodynamic and kinetic parameters of aminopolycarbonate complexes of cobalt(II) and nickel(II) based on isothermal titration calorimetry data.

PubMed

Tesmar, Aleksandra; Wyrzykowski, Dariusz; Muñoz, Eva; Pilarski, Bogusław; Pranczk, Joanna; Jacewicz, Dagmara; Chmurzyński, Lech

2017-04-01

The influence of the different side chain residues on the thermodynamic and kinetic parameters for complexation reactions of the Co 2 + and Ni 2 + ions has been investigated by using the isothermal titration calorimetry (ITC) technique supported by potentiometric titration data. The study was concerned with the 2 common tripodal aminocarboxylate ligands, namely, nitrilotriacetic acid and N-(2-hydroxyethyl) iminodiacetic acid. Calorimetric measurements (ITC) were run in the 2-(N-morpholino)ethanesulfonic acid hydrate (2-(N-morpholino) ethanesulfonic acid), piperazine-N,N'-bis(2-ethanesulfonic acid), and dimethylarsenic acid buffers (0.1 mol L -1 , pH 6) at 298.15 K. The quantification of the metal-buffer interactions and their incorporation into the ITC data analysis enabled to obtain the pH-independent and buffer-independent thermodynamic parameters (K, ΔG, ΔH, and ΔS) for the reactions under study. Furthermore, the kinITC method was applied to obtain kinetic information on complexation reactions from the ITC data. Correlations, based on kinetic and thermodynamic data, between the kinetics of formation of Co 2 + and Ni 2 + complexes and their thermodynamic stabilities are discussed. Copyright © 2016 John Wiley & Sons, Ltd.

The impact of substance use disorders on clinical outcomes in older-adult psychiatric inpatients.

PubMed

Lane, Scott D; da Costa, Sabrina C; Teixeira, Antonio L; Reynolds, Charles F; Diniz, Breno S

2018-02-01

To examine associations among substance use disorder (SUD) and measures of length of stay (LOS) and non-psychiatric medical comorbidity (MEDCO) in older-adult inpatients with serious mental illness (SMI), hypothesizing SUD would be related to worse clinical outcomes. A cross-sectional study analyzed medical records from 2010 to 2016 of 7258 inpatients with SMI ≥ age 50, obtained from a 274-bed psychiatric hospital. Descriptive analyses examined prevalence rates for SUD status (+/-), individual drug classes, and total number of SUDs (polysubstance use disorders). Regression models examined the influence of 2 independent variables of interest: (1) SUD status (+/-) and (2) type of SUD (ie, specific drug), controlling for demographic factors and additional (non-SUD) psychiatric disorders. Two dependent (outcome) variables were examined: LOS and MEDCO. The overall SUD rate was 26%; cocaine was the most common SUD (≈ 10%). SUD status and additional (non-SUD) psychiatric diagnoses were significantly associated with longer LOS (both P < 0.001). For individual SUDs, cocaine, marijuana, opiates, and alcohol were all significantly associated with LOS (all P < 0.01). SUD status, age, sex, admission status, and race were significantly associated with MEDCO (all P < 0.002). For individual SUDs, barbiturates, opiates, and alcohol were all significantly associated with MEDCO (P < 0.01). The prevalence of SUD in this sample underscores concerns related to treating older adults presenting providers with comorbid SUD and SMI. This combination may increase the burden and complexity of care, warranting further investigation into mechanisms and long-term consequences. Copyright © 2017 John Wiley & Sons, Ltd.

Transient phytoextraction agents: establishing criteria for the use of chelants in phytoextraction of recalcitrant metals.

PubMed

Parra, R; Ulery, A L; Elless, M P; Blaylock, M J

2008-01-01

The phytoremediation of recalcitrant metals such as lead and uranium rely on soil amendments to enhance metal availability within the rhizosphere. Because these amendments may persist in soils, agents that not only biodegrade rapidly but also are effective in triggering metal uptake in plants are needed for metals phytoextraction to be considered as an accepted practice. In this study, several biodegradable organic acids and chelating agents were assessed to determine if these amendments can be used in an effective manner, and if their activity and use is consistent with a proposed class of soil amendments for phytoextraction, here termed transient phytoextraction agents (TPAs). A TPA is proposed as an agent that would exhibit both effectiveness in triggering plant accumulation of the targeted metal while minimizing the risk of migration through rapid degradation or inactivation of the soluble complex. Eleven candidate TPAs (acetic acid, ascorbic acid, citric acid, malic acid, oxalic acid, succinic acid, ethylenediaminedisuccinic acid, dicarboxymethylglutamic acid, nitrilotriacetic acid, BayPure CX 100, and the siderophore desferrioxamine B) were tested in batch studies to evaluate their complexation behavior using contaminated soils, with uranium and lead as the target metals. A growth chamber study was then conducted with Brassica juncea (Indian mustard), Helianthus annuus (sunflower), and Festuca arundinacea (tall fescue) grown in a lead-contaminated soil that was treated with the candidate TPAs to assess phytoextraction effectiveness. For the soils tested, citric acid, oxalic acid, and succinic acid were found to be effective complexing agents for uranium phytoextraction, whereas Baypure CX 100 and citric acid exhibited effectiveness for lead phytoextraction.

Multiple Animal Studies for Medical Chemical Defense Program in Soldier/ Patient Decontamination and Drug Development on Task Order 84-6: Pyruvate Dehydrogenase System for Determining the Effectiveness of Arsenic Antidotes

DTIC Science & Technology

1988-03-11

adenine dinucleotide FAD = flavin-adenine dinucleotide iipS2 = lipoic acid lip(SH)2 = dihydrolipoic acid CoA = coenzyme A. SHepatic PDH complex activity...tissues has yet to be fully characterized, but it probably involves arsenic binding to the lipoic acid and dithiol moieties of the complex (Fluharty...covalently bound lipoic acid substrate of dihydrolipoyl transacetylase is greater per mole of L and CVAA than for sodium arsenite. This is possible

An anionic rhodium eta4-quinonoid complex as a multifunctional catalyst for the arylation of aldehydes with arylboronic acids.

PubMed

Son, Seung Uk; Kim, Sang Bok; Reingold, Jeffrey A; Carpenter, Gene B; Sweigart, Dwight A

2005-09-07

The pi-bonded rhodium quinonoid complex, K+[(1,4-benzoquinone)Rh(COD)]-, functions as a good catalyst for the coupling of arylboronic acid and aldehydes to afford diaryl alcohols. The catalysis is heterobimetallic in that both the transition metal and concomitant alkali metal counterion play an integral part in the reaction. In addition, the anionic quinonoid catalyst itself plays a bifunctional role by acting as a ligand to the boronic acid and as a Lewis acid receptor site for the transferring aryl group.

[Lipoproteins as a specific circulatory transport system].

PubMed

Titov, V N

1998-01-01

In accordance with the systemic approach, each circulatory transport system is highly specific and transports an elementary substance from cell to cell in the hydrated medium. In the author's opinion, the lipoprotein system has also a functional specificity and carries the elementary substance fatty acid in the blood stream. A great variety of fatty acids, the individuality of their physicochemical properties, great stereochemic differences of saturated and polyenic fatty acids make their transport virtually impossible. The steric individuality of fatty acids can be reduced if the acids are covalently bonded by a matrix as complex lipids. For formation of complex lipids, nature prefers esterification of fatty acids with alcohols which have a varying hydrophoby, such as glycerol, sphingosine, cholesterol, cetyl alcohol. The steric differences of saturated and polyenic fatty acids form a basis for their being structurized in different lipids. Triacyl glycerides are a transport form of saturated, monounsaturated fatty acids and their transforms and give rise to a crystalline phase. Phospholipids and cholesterol esters are a transport form of mainly polyunsaturated fatty acids in the polar phase in the former case and in the crystalline phase in the latter one. The individual apolipoproteins structure complex lipids into individual lipoprotein particles and transport them in the hydrated medium of blood flow. Saturated fatty acids chiefly transport lipoprotein particles formed by apoB-48- and apoB-100-isoproteins. Polyenic acids transport mainly high-density apoA-1-lipoprotein particles, which makes up a main physiological function of the latter. Cholesterol is nothing more than a matrix; it reesterifies polyenic fatty acids from the polar transport form of phospholipids into the unpolar transport form of cholesterol esters. Cholesterol esterification of polyenic fatty acids may structure complex lipid in the unpolar phase and transport it to the cells via apoB-100-ligand-receptor interaction, which is considered to be a key stage in the multistage process of active transport to the cells of polyenic fatty acids. However, the significant differences of active and inactive transport of polyenic fatty acids in the blood stream await a separate consideration.

Structural, luminescence, thermodynamic and theoretical studies on mononuclear complexes of Eu(III) with pyridine monocarboxylate-N-oxides in aqueous solution

NASA Astrophysics Data System (ADS)

Dumpala, Rama Mohana Rao; Rawat, Neetika; Boda, Anil; Ali, Sk. Musharaf; Tomar, B. S.

2018-02-01

The mononuclear complexes formed by Eu(III) with three isomeric pyridine monocarboxylate-N-oxides namely picolinic acid-N-oxide (PANO), nicotinic acid-N-oxide (NANO) and isonicotinic acid-N-oxide (IANO) in aqueous solutions were studied by potentiometry, luminescence spectroscopy and isothermal titration calorimetry (ITC) to determine the speciation, coordination, luminescence properties and thermodynamic parameters of the complexes formed during the course of the reaction. More stable six membered chelate complexes with stoichiometry (MLi, i = 1-4) are formed by Eu(III) with PANO while non chelating ML and ML2 complexes are formed by NANO and IANO. The stability of Eu(III) complexes follow the order PANO > IANO > NANO. The ITC studies inferred an endothermic and innersphere complex formation of Eu(III)-PANO and Eu(III)-IANO whereas an exothermic and outer-sphere complex formation for Eu(III)-NANO. The luminescence life time data further supported the ITC results. Density functional theoretical calculations were carried out to optimize geometries of the complexes and to estimate the energies, structural parameters (bond distances, bond angles) and charges on individual atoms of the same. Theoretical approximations are found to be in good agreement with the experimental observations.

Resistant starch type V formation in brown lentil (Lens culinaris Medikus) starch with different lipids/fatty acids.

PubMed

Okumus, Bahar Nur; Tacer-Caba, Zeynep; Kahraman, Kevser; Nilufer-Erdil, Dilara

2018-02-01

This study aimed to characterize the brown lentil (Lens culinaris Medikus) starch and investigate the formation of amylose-lipid complexes (Resistant Starch Type V) by the addition of different lipids/fatty acids (10%, w/w) to both raw and cooked starch samples. Resistant starch content (measured by the official method of AACCI (Method 32-40), using the resistant starch assay kit) of raw brown lentil starch (BLS) increased significantly by the additions of lipids/fatty acids, starch sample complexed with HSO (hydrogenated sunflower oil) (14.1±0.4%) being the highest. For the cooked starch/lipid complexes, more profound effect was evident (22.2-67.7%). Peak, breakdown and trough viscosity values of the amylose-lipid complexed starches were significantly lower than that of BLS (p<0.05), while significant decreases in the setback and final viscosities were only detected in oil samples, but not in fatty acids. Each lipid in concern exerted different effects on the digestibility of starch and amylose-lipid complex formation while having no substantial differential effects on the thermal properties of starch depicted by differential scanning calorimetry (DSC). Amylose-lipid complex formation with suitable fatty acids/lipids seems a promising way of increasing resistant starch content of food formulations. Although the applications being quite uncommon yet, brown lentil seems to have potential both as a starch and also as a resistant starch source. Copyright © 2017 Elsevier Ltd. All rights reserved.

Enhanced anti-cancer efficacy to cancer cells by doxorubicin loaded water-soluble amino acid-modified β-cyclodextrin platinum complexes.

PubMed

Zhao, Mei-Xia; Zhao, Meng; Zeng, Er-Zao; Li, Yang; Li, Jin-Ming; Cao, Qian; Tan, Cai-Ping; Ji, Liang-Nian; Mao, Zong-Wan

2014-08-01

The effective targeted delivery of insoluble anticancer drugs to increase the intracellular drug concentration has become a focus in cancer therapy. In this system, two water-soluble amino acid-modified β-cyclodextrin (β-CD) platinum complexes were reported. They showed preferable binding ability to DNA and effective inhibition to cancer cells, and they could bind and unwind pBR322 DNA in a manner which was similar to cisplatin. Besides, our platinum complexes could effectively deliver the anticancer drug doxorubicin (Dox) into cells and had higher cell inhibition ratio, but less toxicity on the normal cells, compared with cancer cells. In this combination system, Dox was encapsulated into the hydrophobic cavities of β-CD at the optimum molar ratio of 1:1, which were validated by UV-visible (UV-vis) absorption spectroscopy, fluorescence spectroscopy and MTT experiments. Moreover, the combination system had higher cell inhibition ratio than free Dox and amino acid-modified β-CD platinum complexes, and the results of high content screening (HCS) showed that Dox-loaded amino acid-modified β-CD platinum complexes could permeate the cell membrane and enter cells, suggesting the efficient transport of Dox across the membranes with the aid of the β-CD. We expect that the amino acid-modified β-CD platinum complexes will deliver the antitumor drug Dox to enhance intracellular drug accumulation and such combination system showed great potential as an antitumor drug. Copyright © 2014 Elsevier Inc. All rights reserved.

Effect of ultrasonic waves on the water turbidity during the oxidation of phenol. Formation of (hydro)peroxo complexes.

PubMed

Villota, Natalia; Lomas, Jose M; Camarero, Luis M

2017-11-01

Analysis of the kinetics of aqueous phenol oxidation by a sono-Fenton process reveals that the via involving ortho-substituted intermediates prevails: catechol (25.0%), hydroquinone (7.7%) and resorcinol (0.6%). During the oxidation, water rapidly acquires color that reaches its maximum intensity at the maximum concentration of p-benzoquinone. Turbidity formation occurs at a slower rate. Oxidant dosage determines the nature of the intermediates, being trihydroxylated benzenes (pyrogallol, hydroxyhydroquinone) and muconic acid the main precursors causing turbidity. It is found that the concentration of iron species and ultrasonic waves affects the intensity of the turbidity. The pathway of (hydro)peroxo-iron(II) complexes formation is proposed. Operating with 20.0-27.8mgFe 2+ /kW rates leads to formation of (hydro)peroxo-iron(II) complexes, which induce high turbidity levels. These species would dissociate into ZZ-muconic acid and ferrous ions. Applying relationships around 13.9mgFe 2+ /kW, the formation of (hydro)peroxo-iron(III) complexes would occur, which could react with carboxylic acids (2,5-dioxo-3-hexenedioic acid). That reaction induces turbidity slower. This is due to the organic substrate reacting with two molecules of the (hydro)peroxo complex. Therefore, it is necessary to accelerate the iron regeneration, intensifying the ultrasonic irradiation. Afterwards, this complex would dissociate into maleic acid and ferric ions. Copyright © 2017 Elsevier B.V. All rights reserved.

Thermodynamic characteristics of the interaction between nicotinic acid and phenylalanine in an aqueous buffer solution at 298 K

NASA Astrophysics Data System (ADS)

Badelin, V. G.; Tyunina, E. Yu.; Mezhevoi, I. N.; Tarasova, G. N.

2013-08-01

The interaction between L-phenylalanine and nicotinic acid is studied by solution calorimetry in an aqueous buffer solution (pH 7.35) at different ratios of the reagents. Experimental data on the enthalpy of dissolution of amino acid in the buffer solution of nicotinic acid at 298.15 K are calculated. The values of thermodynamic parameters for the complexation of L-phenylalanine with nicotinic acid are calculated. It is shown that the formation of a 1: 2 molecular complex is stabilized by the entropy factor due to the dominant role of the dehydration effect of initial reagents.

Compact oleic acid in HAMLET.

PubMed

Fast, Jonas; Mossberg, Ann-Kristin; Nilsson, Hanna; Svanborg, Catharina; Akke, Mikael; Linse, Sara

2005-11-07

HAMLET (human alpha-lactalbumin made lethal to tumor cells) is a complex between alpha-lactalbumin and oleic acid that induces apoptosis in tumor cells, but not in healthy cells. Heteronuclear nuclear magnetic resonance (NMR) spectroscopy was used to determine the structure of 13C-oleic acid in HAMLET, and to study the 15N-labeled protein. Nuclear Overhauser enhancement spectroscopy shows that the two ends of the fatty acid are in close proximity and close to the double bond, indicating that the oleic acid is bound to HAMLET in a compact conformation. The data further show that HAMLET is a partly unfolded/molten globule-like complex under physiological conditions.

A Comparison of Gallium and Indium Alkoxide Complexes as Catalysts for Ring-Opening Polymerization of Lactide.

PubMed

Kremer, Alexandre B; Andrews, Ryan J; Milner, Matthew J; Zhang, Xu R; Ebrahimi, Tannaz; Patrick, Brian O; Diaconescu, Paula L; Mehrkhodavandi, Parisa

2017-02-06

The impact of the metal size and Lewis acidity on the polymerization activity of group 13 metal complexes was studied, and it was shown that, within the same ligand family, indium complexes are far more reactive and selective than their gallium analogues. To this end, gallium and aluminum complexes supported by a tridentate diaminophenolate ligand, as well as gallium complexes supported by N,N'-ethylenebis(salicylimine)(salen) ligands, were synthesized and compared to their indium analogues. Using the tridentate ligand set, it was possible to isolate the gallium chloride complexes 3 and (±)-4 and the aluminum analogues 5 and (±)-6. The alkoxygallium complex (±)-2, supported by a salen ligand, was also prepared and characterized and, along with the three-component system GaCl 3 /BnOH/NEt 3 , was tested for the ring-opening polymerization of lactide and ε-caprolactone. The polymerization rates and selectivities of both systems were significantly lower than those for the indium analogues. The reaction of (±)-2 with 1 equiv of lactide forms the first insertion product, which is stable in solution and can be characterized at room temperature. In order to understand the differences of the reactivity within the group 13 metal complexes, a Lewis acidity study using triethylphosphine oxide (the Gutmann-Beckett method) was undertaken for a series of aluminum, gallium, and indium halide complexes; this study shows that indium halide complexes are less Lewis acidic than their aluminum and gallium analogues. Density functional theory calculations show that the Mulliken charges for the indium complexes are higher than those for the gallium analogues. These data suggest that the impact of ligands on the reactivity is more significant than that of the metal Lewis acidity.

Gallium(iii) and iron(iii) complexes of quinolone antimicrobials.

PubMed

Mjos, Katja Dralle; Cawthray, Jacqueline F; Polishchuk, Elena; Abrams, Michael J; Orvig, Chris

2016-08-16

Iron is an essential nutrient for many microbes. According to the "Trojan Horse Hypothesis", biological systems have difficulties distinguishing between Fe(3+) and Ga(3+), which constitutes the antimicrobial efficacy of the gallium(iii) ion. Nine novel tris(quinolono)gallium(iii) complexes and their corresponding iron(iii) analogs have been synthesized and fully characterized. Quinolone antimicrobial agents from three drug generations were used in this study: ciprofloxacin, enoxacin, fleroxacin, levofloxacin, lomefloxacin, nalidixic acid, norfloxacin, oxolinic acid, and pipemidic acid. The antimicrobial efficacy of the tris(quinolono)gallium(iii) complexes was studied against E. faecalis and S. aureus (both Gram-positive), as well as E. coli, K. pneumonia, and P. aeruginosa (all Gram-negative) in direct comparison to the tris(quinolono)iron(iii) complexes and the corresponding free quinolone ligands at various concentrations. For the tris(quinolono)gallium(iii) complexes, no combinational antimicrobial effects between Ga(3+) and the quinolone antimicrobial agents were observed.

Spectroscopic characterization of charge-transfer complexes of morpholine with chloranilic and picric acids in organic media: crystal structure of bis(morpholinium 2,4,6-trinitrocyclohexanolate).

PubMed

Refat, Moamen S; El-Zayat, Lamia A; Yeşilel, Okan Zafer

2010-02-01

Electron donor-acceptor interaction of morpholine (morp) with chloranilic acid (cla) and picric acid (pa) as pi-acceptors was investigated spectrophotometrically and found to form stable charge-transfer (CT) complexes (n-pi*) of [(Hmorp)(2)(cla)] and [(Hmorp)(pa)](2). The donor site involved in CT interaction is morpholine nitrogen. These complexes are easily synthesized from the reaction of morp with cla and pa within MeOH and CHCl(3) solvents, respectively. (1)HNMR, IR, elemental analyses, and UV-vis techniques characterize the two morpholinium charge-transfer complexes. Benesi-Hildebrand and its modification methods were applied to the determination of association constant (K), molar extinction coefficient (epsilon). The X-ray crystal structure was carried out for the interpretation the predict structure of the [(Hmorp)(pa)](2) complex. Copyright (c) 2009 Elsevier B.V. All rights reserved.

Spectroscopic characterization of charge-transfer complexes of morpholine with chloranilic and picric acids in organic media: Crystal structure of bis(morpholinium 2,4,6-trinitrocyclohexanolate)

NASA Astrophysics Data System (ADS)

Refat, Moamen S.; El-Zayat, Lamia A.; Yeşilel, Okan Zafer

2010-02-01

Electron donor-acceptor interaction of morpholine (morp) with chloranilic acid (cla) and picric acid (pa) as π-acceptors was investigated spectrophotometrically and found to form stable charge-transfer (CT) complexes (n-π*) of [(Hmorp) 2(cla)] and [(Hmorp)(pa)] 2. The donor site involved in CT interaction is morpholine nitrogen. These complexes are easily synthesized from the reaction of morp with cla and pa within MeOH and CHCl 3 solvents, respectively. 1HNMR, IR, elemental analyses, and UV-vis techniques characterize the two morpholinium charge-transfer complexes. Benesi-Hildebrand and its modification methods were applied to the determination of association constant ( K), molar extinction coefficient ( ɛ). The X-ray crystal structure was carried out for the interpretation the predict structure of the [(Hmorp)(pa)] 2 complex.

Asymmetric synthesis of α-amino acids via homologation of Ni(II) complexes of glycine Schiff bases. Part 3: Michael addition reactions and miscellaneous transformations.

PubMed

Aceña, José Luis; Sorochinsky, Alexander E; Soloshonok, Vadim

2014-09-01

The major goal of this review is a critical discussion of the literature data on asymmetric synthesis of α-amino acids via Michael addition reactions involving Ni(II)-complexes of amino acids. The material covered is divided into two conceptually different groups dealing with applications of: (a) Ni(II)-complexes of glycine as C-nucleophiles and (b) Ni(II)-complexes of dehydroalanine as Michael acceptors. The first group is significantly larger and consequently subdivided into four chapters based on the source of stereocontrolling element. Thus, a chiral auxiliary can be used as a part of nucleophilic glycine Ni(II) complex, Michael acceptor or both, leading to the conditions of matching vs. mismatching stereochemical preferences. The particular focus of the review is made on the practical aspects of the methodology under discussion and mechanistic considerations.

The Impact of Single Amino Acids on Growth and Volatile Aroma Production by Saccharomyces cerevisiae Strains

PubMed Central

Fairbairn, Samantha; McKinnon, Alexander; Musarurwa, Hannibal T.; Ferreira, António C.; Bauer, Florian F.

2017-01-01

Nitrogen availability and utilization by Saccharomyces cerevisiae significantly influence fermentation kinetics and the production of volatile compounds important for wine aroma. Amino acids are the most important nitrogen source and have been classified based on how well they support growth. This study evaluated the effect of single amino acids on growth kinetics and major volatile production of two phenotypically different commercial wine yeast strains in synthetic grape must. Four growth parameters, lag phase, maximum growth rate, total biomass formation and time to complete fermentation were evaluated. In contrast with previous findings, in fermentative conditions, phenylalanine and valine supported growth well and asparagine supported it poorly. The four parameters showed good correlations for most amino acid treatments, with some notable exceptions. Single amino acid treatments resulted in the predictable production of aromatic compounds, with a linear correlation between amino acid concentration and the concentration of aromatic compounds that are directly derived from these amino acids. With the increased complexity of nitrogen sources, linear correlations were lost and aroma production became unpredictable. However, even in complex medium minor changes in amino acid concentration continued to directly impact the formation of aromatic compounds, suggesting that the relative concentration of individual amino acids remains a predictor of aromatic outputs, independently of the complexity of metabolic interactions between carbon and nitrogen metabolism and between amino acid degradation and utilization pathways. PMID:29312237

The Impact of Single Amino Acids on Growth and Volatile Aroma Production by Saccharomyces cerevisiae Strains.

PubMed

Fairbairn, Samantha; McKinnon, Alexander; Musarurwa, Hannibal T; Ferreira, António C; Bauer, Florian F

2017-01-01

Nitrogen availability and utilization by Saccharomyces cerevisiae significantly influence fermentation kinetics and the production of volatile compounds important for wine aroma. Amino acids are the most important nitrogen source and have been classified based on how well they support growth. This study evaluated the effect of single amino acids on growth kinetics and major volatile production of two phenotypically different commercial wine yeast strains in synthetic grape must. Four growth parameters, lag phase, maximum growth rate, total biomass formation and time to complete fermentation were evaluated. In contrast with previous findings, in fermentative conditions, phenylalanine and valine supported growth well and asparagine supported it poorly. The four parameters showed good correlations for most amino acid treatments, with some notable exceptions. Single amino acid treatments resulted in the predictable production of aromatic compounds, with a linear correlation between amino acid concentration and the concentration of aromatic compounds that are directly derived from these amino acids. With the increased complexity of nitrogen sources, linear correlations were lost and aroma production became unpredictable. However, even in complex medium minor changes in amino acid concentration continued to directly impact the formation of aromatic compounds, suggesting that the relative concentration of individual amino acids remains a predictor of aromatic outputs, independently of the complexity of metabolic interactions between carbon and nitrogen metabolism and between amino acid degradation and utilization pathways.

Spectrophotometric and spectroscopic studies of charge transfer complex of 1-Naphthylamine as an electron donor with picric acid as an electron acceptor in different polar solvents

NASA Astrophysics Data System (ADS)

Singh, Neeti; Ahmad, Afaq

2010-08-01

The charge transfer complex of 1-Naphthylamine as a donor with π-acceptor picric acid has been studied spectrophotometrically in different solvents at room temperature. The results indicate that the formation of charge transfer complex is high in less polar solvent. The stoichiometry of the complex was found to be 1:1 by straight line method. The data are analysed in terms of formation constant ( KCT), molar extinction coefficient ( ɛCT), standard free energy (Δ G o), oscillator strength ( ƒ), transition dipole moment ( μ EN), resonance energy ( R N) and ionization potential ( I D). It is concluded that the formation constant ( KCT) of the complex is found to be depends upon the nature of both electron acceptor and donor and also on the polarity of solvents. Further the charge transfer molecular complex between picric acid and 1-Naphthylamine is stabilized by hydrogen bonding.

21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 172.315 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.315 Nicotinamide-ascorbic acid complex...

Signs of antimetastatic activity of palladium complexes of methylenediphosphonic acid in IR spectra

NASA Astrophysics Data System (ADS)

Tolstorozhev, G. B.; Skornyakov, I. V.; Pekhnio, V. I.; Kozachkova, A. N.; Sharykina, N. I.

2012-07-01

We have used Fourier transform IR spectroscopy methods to study normal mouse lung tissue and also after subcutaneous transplantation of a B-16 melanoma tumor in the tissue. We also studied tissues with B-16 melanoma after they were treated with coordination compounds based on palladium complexes of methylenediphosphonic acid. The IR spectra of the lung tissues with metastases in the region of the C = O stretching vibrations are different from the IR spectra of normal tissue. We identified spectroscopic signs of the presence of metastases in the lung. We show that when a cancerous tumor is treated with a preparation of palladium complexes of methylenediphosphonic acid, the spectroscopic signs of the presence of metastases in the lung are missing. After treatment with the optimal dose of this drug, the IR spectrum of the lung tissue in which multiple metastases were present before treatment corresponds to the spectrum of normal tissue. We have determined the efficacy of the antitumor activity of coordination compounds based on palladium complexes of methylenediphosphonic acid.

Effect of 18β-glycyrrhetinic acid and hydroxypropyl γcyclodextrin complex on indomethacin-induced small intestinal injury in mice.

PubMed

Ishida, Tsukasa; Miki, Ikuya; Tanahashi, Toshihito; Yagi, Saori; Kondo, Yasuyuki; Inoue, Jun; Kawauchi, Shoji; Nishiumi, Sin; Yoshida, Masaru; Maeda, Hideko; Tode, Chisato; Takeuchi, Atsuko; Nakayama, Hirokazu; Azuma, Takeshi; Mizuno, Shigeto

2013-08-15

Non-steroidal anti-inflammatory drugs (NSAIDs)-induced small intestinal injury is a serious clinical event with recent advances of diagnostic technologies, but a successful therapeutic method to treat such injuries is still lacking. Licorice, a traditional herbal medicine, and its derivatives have been widely used for the treatment of a variety of diseases due to their extensive biological actions. However, it is unknown whether these derivatives have an effect on NSAIDs-induced small intestinal damage. Previously, the anti-inflammatory effects of three compounds extracted from the licorice root, glycyrrhizin, 18β-glycyrrhetinic acid, and dipotassium glycyrrhizinate, were compared in vitro cell culture. The most prominent inhibitory effect on the tumor necrosis factor-α (TNF-α) production was observed with the administration of 18β-glycyrrhetinic acid as an active metabolite of glycyrrhizin. In this study, a complex compound of 18β-glycyrrhetinic acid and hydroxypropyl γcyclodextrin was examined to improve the oral bioavailability. After administration of this complex to indomethacin treated mice, a significantly high plasma concentration of 18β-glycyrrhetinic acid was detected using the tandem mass spectrometry coupled with the HPLC. Furthermore, the complex form of 18β-glycyrrhetinic acid and hydroxypropyl γcyclodextrin reduced mRNA expressions of TNF-α, interleukin (IL)-1β, and IL-6, which was histologically confirmed in the improvement of indomethacin-induced small intestinal damage. These results suggest that the complex of 18β-glycyrrhetinic acid and hydroxypropyl γcyclodextrin has the potential therapeutic value for preventing the adverse effects of indomethacin-induced small intestinal injury. Copyright © 2013 Elsevier B.V. All rights reserved.

Palladium alpha-lipoic acid complex formulation enhances activities of Krebs cycle dehydrogenases and respiratory complexes I-IV in the heart of aged rats.

PubMed

Sudheesh, N P; Ajith, T A; Janardhanan, K K; Krishnan, C V

2009-08-01

Age-related decline in the capacity to withstand stress, such as ischemia and reperfusion, results in congestive heart failure. Though the mechanisms underlying cardiac decay are not clear, age dependent somatic damages to mitochondrial DNA (mtDNA), loss of mitochondrial function, and a resultant increase in oxidative stress in heart muscle cells may be responsible for the increased risk for cardiovascular diseases. The effect of a safe nutritional supplement, POLY-MVA, containing the active ingredient palladium alpha-lipoic acid complex, was evaluated on the activities of the Krebs cycle enzymes such as isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase, succinate dehydrogenase, and malate dehydrogenase as well as mitochondrial complexes I, II, III, and IV in heart mitochondria of aged male albino rats of Wistar strain. Administration of 0.05 ml/kg of POLY-MVA (which is equivalent to 0.38 mg complexed alpha-lipoic acid/kg, p.o), once daily for 30 days, was significantly (p<0.05) effective to enhance the Krebs cycle dehydrogenases, and mitochondrial electron transport chain complexes. The unique electronic and redox properties of palladium alpha-lipoic acid complex appear to be a key to this physiological effectiveness. The results strongly suggest that this formulation might be effective to protect the aging associated risk of cardiovascular and neurodegenerative diseases.

Synthesis, physicochemical studies, embryos toxicity and DNA interaction of some new Iron(II) Schiff base amino acid complexes

NASA Astrophysics Data System (ADS)

Abdel-Rahman, Laila H.; El-Khatib, Rafat M.; Nassr, Lobna A. E.; Abu-Dief, Ahmed M.

2013-05-01

New Fe(II) Schiff base amino acid complexes derived from the condensation of o-hydroxynaphthaldehyde with L-alanine, L-phenylalanine, L-aspartic acid, L-histidine and L-arginine were synthesized and characterized by elemental analysis, IR, electronic spectra, and conductance measurements. The stoichiometry and the stability constants of the complexes were determined spectrophotometrically. The investigated Schiff bases exhibited tridentate coordination mode with the general formulae [Fe(HL)2]·nH2O for all amino acids except L-histidine. But in case of L-histidine, the ligand acts as tetradentate ([FeL(H2O)2]·2H2O), where HL = mono anion and L = dianion of the ligand. The structure of the prepared complexes is suggested to be octahedral. The prepared complexes were tested for their toxicity on chick embryos and found to be safe until a concentration of 100 μg/egg with full embryos formation. The interaction between CT-DNA and the investigated complexes were followed by spectrophotometry and viscosity measurements. It was found that, the prepared complexes bind to DNA via classical intercalative mode and showed a different DNA cleavage activity with the sequence: nhi > nari > nali > nasi > nphali. The thermodynamic Profile of the binding of nphali complex and CT-DNA was constructed by analyzing the experimental data of absorption titration and UV melting studies with the McGhee equation, van't Hoff's equation, and the Gibbs-Helmholtz equation.

Thermodynamic, Spectroscopic, and Computational Studies of f -Element Complexation by N -Hydroxyethyl-diethylenetriamine- N,N ', N ", N"-tetraacetic Acid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grimes, Travis S.; Heathman, Colt R.; Jansone-Popova, Santa

Potentiometric and spectroscopic techniques were combined with DFT calculations to probe the coordination environment and determine thermodynamic features of trivalent f-element complexation by N-hydroxyethyl-diethylenetriamine-N,N',N",N"-tetraacetic acid, HEDTTA. Ligand protonation constants and lanthanide stability constants were determined using potentiometry. Five protonation constants were accessible in I = 2.0 M (H +/Na +)ClO 4. UV–vis spectroscopy was used to determine stability constants for Nd 3+ and Am 3+ complexation with HEDTTA. Luminescence spectroscopy indicates two water molecules in the inner coordination sphere of the Eu/HEDTTA complex, suggesting HEDTTA is heptadentate. Luminescence data was supported by DFT calculations, which demonstrate that substitution of themore » acetate pendant arm by a N-hydroxyethyl group weakens the metal–nitrogen bond. This bond elongation is reflected in HEDTTA’s ability to differentiate trivalent actinides from trivalent lanthanides. The trans-lanthanide Ln/HEDTTA complex stability trend is analogous to Ln/DTPA complexation; however, the loss of one chelate ring resulting from structural substitution weakens the complexation by ~3 orders of magnitude. Successful separation of trivalent americium from trivalent lanthanides was demonstrated when HEDTTA was utilized as aqueous holdback complexant in a liquid–liquid system. Time-dependent extraction studies for HEDTTA were compared to diethylenetriamine-N,N,N',N",N"-pentaacetic acid (DTPA) and N-hydroxyethyl-ethylenediamine-N,N',N'-triacetic acid (HEDTA). The results presented here indicate substantially enhanced phase-transfer kinetic rates for mixtures containing HEDTTA.« less

Thermodynamic, Spectroscopic, and Computational Studies of f -Element Complexation by N -Hydroxyethyl-diethylenetriamine- N,N ', N ", N"-tetraacetic Acid

DOE PAGES

Grimes, Travis S.; Heathman, Colt R.; Jansone-Popova, Santa; ...

2017-01-24

Potentiometric and spectroscopic techniques were combined with DFT calculations to probe the coordination environment and determine thermodynamic features of trivalent f-element complexation by N-hydroxyethyl-diethylenetriamine-N,N',N",N"-tetraacetic acid, HEDTTA. Ligand protonation constants and lanthanide stability constants were determined using potentiometry. Five protonation constants were accessible in I = 2.0 M (H +/Na +)ClO 4. UV–vis spectroscopy was used to determine stability constants for Nd 3+ and Am 3+ complexation with HEDTTA. Luminescence spectroscopy indicates two water molecules in the inner coordination sphere of the Eu/HEDTTA complex, suggesting HEDTTA is heptadentate. Luminescence data was supported by DFT calculations, which demonstrate that substitution of themore » acetate pendant arm by a N-hydroxyethyl group weakens the metal–nitrogen bond. This bond elongation is reflected in HEDTTA’s ability to differentiate trivalent actinides from trivalent lanthanides. The trans-lanthanide Ln/HEDTTA complex stability trend is analogous to Ln/DTPA complexation; however, the loss of one chelate ring resulting from structural substitution weakens the complexation by ~3 orders of magnitude. Successful separation of trivalent americium from trivalent lanthanides was demonstrated when HEDTTA was utilized as aqueous holdback complexant in a liquid–liquid system. Time-dependent extraction studies for HEDTTA were compared to diethylenetriamine-N,N,N',N",N"-pentaacetic acid (DTPA) and N-hydroxyethyl-ethylenediamine-N,N',N'-triacetic acid (HEDTA). The results presented here indicate substantially enhanced phase-transfer kinetic rates for mixtures containing HEDTTA.« less

Arachidonic acid depletion extends survival of cold-stored platelets by interfering with the [glycoprotein Ibα – 14-3-3ζ] association

PubMed Central

van der Wal, Dianne E.; Gitz, Eelo; Du, Vivian X.; Lo, Kimberly S.L.; Koekman, Cornelis A.; Versteeg, Sabine; Akkerman, Jan Willem N.

2012-01-01

Background Cold storage of platelets reduces bacterial growth and preserves their hemostatic properties better than current procedures do. However, storage at 0°C induces [14-3-3ζ-glycoprotein Ibα] association, 14-3-3ζ release from phospho-Bad, Bad activation and apoptosis. Design and Methods We investigated whether arachidonic acid, which also binds 14-3-3ζ, contributes to coldinduced apoptosis. Results Cold storage activated P38-mitogen-activated protein kinase and released arachidonic acid, which accumulated due to cold inactivation of cyclooxygenase-1/thromboxane synthase. Accumulated arachidonic acid released 14-3-3ζ from phospho-Bad and decreased the mitochondrial membrane potential, which are steps in the induction of apoptosis. Addition of arachidonic acid did the same and its depletion made platelets resistant to cold-induced apoptosis. Incubation with biotin-arachidonic acid revealed formation of an [arachidonic acid-14-3-3ζ-glycoprotein Ibα] complex. Indomethacin promoted complex formation by accumulating arachidonic acid and released 14-3-3ζ from cyclo-oxygenase-1. Arachidonic acid depletion prevented the cold-induced reduction of platelet survival in mice. Conclusions We conclude that cold storage induced apoptosis through an [arachidonic acid-14-3-3ζ-glycoprotein Ibα] complex, which released 14-3-3ζ from Bad in an arachidonic acid-dependent manner. Although arachidonic acid depletion reduced agonist-induced thromboxane A2 formation and aggregation, arachidonic acid repletion restored these functions, opening ways to reduce apoptosis during storage without compromising hemostatic functions post-transfusion. PMID:22371179

Bioorganometallic chemistry. 8. The molecular recognition of aromatic and aliphatic amino acids and substituted aromatic and aliphatic carboxylic acid guests with supramolecular ({eta}{sup 5}-pentamethylcyclopentadienyl)rhodium - nucleobase, nucleoside, and nucleotide cyclic trimer hosts via non-covalent {pi}-{pi} and hydrophobic interactions in water: Steric, electronic, and conformational parameters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, H.; Ogo, Seiji; Fish, R.H.

Molecular recognition, via non-covalent processes such as hydrogen bonding, {pi}-{pi}, and hydrophobic interactions, is an important biological phenomenon for guests, such as drugs, proteins, and other important biological molecules with, for example, host DNA/RNA. We have studied a novel molecular recognition process using guests that encompass aromatic and aliphatic amino acids [L-alanine, L-glutamine (L-Gln), L-histidine, L-isoleucine(L-Ile), L-leucine(L-Leu), L-phenylalanine(L-Phe), L-proline, L-tryptophan(L-Trp), L-valine(L-Val)], substituted aromatic carboxylic acids o-, m-, p-aminobenzoic acids (G1-3), benzoic acid (G4), phenylacetic acid (G5), p-methoxyphenylacetic acid (G6), o-methyoxybenozoic acid (G9), o-nitrobenzoic acid (G10), and aliphatic carboxylic acids [cyclohexylacetic acid (G7), 1-adamantanecarboxylic acid (G8)] with supramolecular, bioorganometallic hosts, ({eta}{supmore » 5}-pentamethylcyclopentadienyl)rhodium (Cp{sup *}Rh)-nucleobase, nucleoside, and nucleotide cyclic trimer complexes in aqueous solution at pH 7, utilizing {sup 1}H NMR, NOE, and molecular modeling techniques, and, as well, determining association constants (K{sub a}) and free energies of complexation ({Delta}{degree}G). The host-guest complexation occurs predominantly via non-covalent {pi}-{pi}, hydrophobic, and possible subtle H-bonding interactions, with steric, electronic, and molecular conformational parameters as important criteria. 8 refs., 6 figs., 3 tabs.« less

Pseudoracemic amino acid complexes: blind predictions for flexible two-component crystals.

PubMed

Görbitz, Carl Henrik; Dalhus, Bjørn; Day, Graeme M

2010-08-14

Ab initio prediction of the crystal packing in complexes between two flexible molecules is a particularly challenging computational chemistry problem. In this work we present results of single crystal structure determinations as well as theoretical predictions for three 1 ratio 1 complexes between hydrophobic l- and d-amino acids (pseudoracemates), known from previous crystallographic work to form structures with one of two alternative hydrogen bonding arrangements. These are accurately reproduced in the theoretical predictions together with a series of patterns that have never been observed experimentally. In this bewildering forest of potential polymorphs, hydrogen bonding arrangements and molecular conformations, the theoretical predictions succeeded, for all three complexes, in finding the correct hydrogen bonding pattern. For two of the complexes, the calculations also reproduce the exact space group and side chain orientations in the best ranked predicted structure. This includes one complex for which the observed crystal packing clearly contradicted previous experience based on experimental data for a substantial number of related amino acid complexes. The results highlight the significant recent advances that have been made in computational methods for crystal structure prediction.

Modular Organization of Residue-Level Contacts Shapes the Selection Pressure on Individual Amino Acid Sites of Ribosomal Proteins.

PubMed

Mallik, Saurav; Kundu, Sudip

2017-04-01

Understanding the molecular evolution of macromolecular complexes in the light of their structure, assembly, and stability is of central importance. Here, we address how the modular organization of native molecular contacts shapes the selection pressure on individual residue sites of ribosomal complexes. The bacterial ribosomal complex is represented as a residue contact network where nodes represent amino acid/nucleotide residues and edges represent their van der Waals interactions. We find statistically overrepresented native amino acid-nucleotide contacts (OaantC, one amino acid contacts one or multiple nucleotides, internucleotide contacts are disregarded). Contact number is defined as the number of nucleotides contacted. Involvement of individual amino acids in OaantCs with smaller contact numbers is more random, whereas only a few amino acids significantly contribute to OaantCs with higher contact numbers. An investigation of structure, stability, and assembly of bacterial ribosome depicts the involvement of these OaantCs in diverse biophysical interactions stabilizing the complex, including high-affinity protein-RNA contacts, interprotein cooperativity, intersubunit bridge, packing of multiple ribosomal RNA domains, etc. Amino acid-nucleotide constituents of OaantCs with higher contact numbers are generally associated with significantly slower substitution rates compared with that of OaantCs with smaller contact numbers. This evolutionary rate heterogeneity emerges from the strong purifying selection pressure that conserves the respective amino acid physicochemical properties relevant to the stabilizing interaction with OaantC nucleotides. An analysis of relative molecular orientations of OaantC residues and their interaction energetics provides the biophysical ground of purifying selection conserving OaantC amino acid physicochemical properties. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Complexation of lanthanides and actinides by acetohydroxamic acid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, R.J.; Sinkov, S.I.; Choppin, G.R.

2008-07-01

Acetohydroxamic acid (AHA) has been proposed as a suitable reagent for the complexant-based, as opposed to reductive, stripping of plutonium and neptunium ions from the tributylphosphate solvent phase in advanced PUREX or UREX processes designed for future nuclear-fuel reprocessing. Stripping is achieved by the formation of strong hydrophilic complexes with the tetravalent actinides in nitric acid solutions. To underpin such applications, knowledge of the complexation constants of AHA with all relevant actinide (5f) and lanthanide (4f) ions is therefore important. This paper reports the determination of stability constants of AHA with the heavier lanthanide ions (Dy-Yb) and also U(IV) andmore » Th(IV) ions. Comparisons with our previously published AHA stability-constant data for 4f and 5f ions are made. (authors)« less

Formation of Mixed-Ligand Complexes of Metals(II) with Monoamine Complexones and Amino Acids in Solution

NASA Astrophysics Data System (ADS)

Pyreu, D. F.; Gridchin, S. N.

2018-05-01

The formation of mixed-ligand complexes in the M(II)-Nta, Ida-L (M = Cu(II), Ni, Zn, Co(II), L = Ser, Thr, Asp, Arg, Asn) systems, where Ida and Nta are the residues of iminodiacetic and nitrilotriacetic acids, respectively, is studied using pH measurements, calorimetry and spectrophotometry. The thermodynamic parameters (log K, Δr G 0, Δr H, Δr S) of their formation at 298.15 K and ionic strength I = 0.5 (KNO3) are determined. The most likely scenario of amino acid residue coordination in the composition of mixed complexes is discussed.

Direction to practical production of hydrogen by formic acid dehydrogenation with Cp*Ir complexes bearing imidazoline ligands

DOE PAGES

Onishi, Naoya; Ertem, Mehmed Z.; Xu, Shaoan; ...

2016-11-10

In a Cp*Ir complex with a bidentate pyridyl-imidazoline ligand achieved the evolution of 1.02 m 3 of H 2/CO 2 gases by formic acid dehydrogenation without any additives or adjustments in the solution system. Furthermore, the pyridyl-imidazoline moieties provided the optimum pH to be 1.7, resulting in high activity and stability even at very acidic conditions.

Direction to practical production of hydrogen by formic acid dehydrogenation with Cp*Ir complexes bearing imidazoline ligands

DOE Office of Scientific and Technical Information (OSTI.GOV)

Onishi, Naoya; Ertem, Mehmed Z.; Xu, Shaoan

In a Cp*Ir complex with a bidentate pyridyl-imidazoline ligand achieved the evolution of 1.02 m 3 of H 2/CO 2 gases by formic acid dehydrogenation without any additives or adjustments in the solution system. Furthermore, the pyridyl-imidazoline moieties provided the optimum pH to be 1.7, resulting in high activity and stability even at very acidic conditions.

Ultraviolet-B radiation mobilizes uranium from uranium-dissolved organic carbon complexes in aquatic systems, demonstrated by asymmetrical flow field-flow fractionation.

PubMed

Nehete, Sachin Vilas; Christensen, Terje; Salbu, Brit; Teien, Hans-Christian

2017-05-05

Humic substances have a tendency to form complexes with metal ions in aquatic medium, impacting the metal mobility, decreasing bioavailability and toxicity. Ultraviolet-B (UV-B) radiation exposure degrades the humic substance, changes their molecular weight distribution and their metal binding capacity in aquatic medium. In this study, we experimented the effect of UV-B radiation on the uranium complexed with fulvic acids and humic acids in a soft water system at different pH, uranium concentrations and radiant exposure. The concentration and distribution of uranium in a complexed form were investigated by asymmetrical flow field-flow fractionation coupled to multi detection technique (AsFlFFF-UV-ICP-MS). The major concentration of uranium present in complexes was primarily associated with average and higher molecular weight fulvic and humic acids components. The concentration of uranium in a complexed form increased with increasing fulvic and humic acid concentrations as well as pH of the solution. The higher molecular weight fraction of uranium was degraded due to the UV-B exposure, transforming about 50% of the uranium-dissolved organic carbon complexes into low molecular weight uranium species in complex form with organic ligands and/or free form. The result also suggests AsFlFFF-UV-ICP-MS to be an important separation and detection technique for understanding the interaction of radionuclides with dissolved organic matter, tracking size distribution changes during degradation of organic complexes for understanding mobility, bioavailability and ecosystem transfer of radionuclides as well as metals. Copyright © 2017 Elsevier B.V. All rights reserved.

Novel Microbial Assemblages Dominate Weathered Sulfide-Bearing Rock from Copper-Nickel Deposits in the Duluth Complex, Minnesota, USA

PubMed Central

Lapakko, Kim A.; Wenz, Zachary J.; Olson, Michael C.; Roepke, Elizabeth W.; Novak, Paige J.; Bailey, Jake V.

2017-01-01

ABSTRACT The Duluth Complex in northeastern Minnesota hosts economically significant deposits of copper, nickel, and platinum group elements (PGEs). The primary sulfide mineralogy of these deposits includes the minerals pyrrhotite, chalcopyrite, pentlandite, and cubanite, and weathering experiments show that most sulfide-bearing rock from the Duluth Complex generates moderately acidic leachate (pH 4 to 6). Microorganisms are important catalysts for metal sulfide oxidation and could influence the quality of water from mines in the Duluth Complex. Nevertheless, compared with that of extremely acidic environments, much less is known about the microbial ecology of moderately acidic sulfide-bearing mine waste, and so existing information may have little relevance to those microorganisms catalyzing oxidation reactions in the Duluth Complex. Here, we characterized the microbial communities in decade-long weathering experiments (kinetic tests) conducted on crushed rock and tailings from the Duluth Complex. Analyses of 16S rRNA genes and transcripts showed that differences among microbial communities correspond to pH, rock type, and experimental treatment. Moreover, microbial communities from the weathered Duluth Complex rock were dominated by taxa that are not typically associated with acidic mine waste. The most abundant operational taxonomic units (OTUs) were from the genera Meiothermus and Sulfuriferula, as well as from diverse clades of uncultivated Chloroflexi, Acidobacteria, and Betaproteobacteria. Specific taxa, including putative sulfur-oxidizing Sulfuriferula spp., appeared to be primarily associated with Duluth Complex rock, but not pyrite-bearing rocks subjected to the same experimental treatment. We discuss the implications of these results for the microbial ecology of moderately acidic mine waste with low sulfide content, as well as for kinetic testing of mine waste. IMPORTANCE Economic sulfide mineral deposits in the Duluth Complex may represent the largest undeveloped source of copper and nickel on Earth. Microorganisms are important catalysts for sulfide mineral oxidation, and research on extreme acidophiles has improved our ability to manage and remediate mine wastes. We found that the microbial assemblages associated with weathered rock from the Duluth Complex are dominated by organisms not widely associated with mine waste or mining-impacted environments, and we describe geochemical and experimental influences on community composition. This report will be a useful foundation for understanding the microbial biogeochemistry of moderately acidic mine waste from these and similar deposits. PMID:28600313

Novel Microbial Assemblages Dominate Weathered Sulfide-Bearing Rock from Copper-Nickel Deposits in the Duluth Complex, Minnesota, USA.

PubMed

Jones, Daniel S; Lapakko, Kim A; Wenz, Zachary J; Olson, Michael C; Roepke, Elizabeth W; Sadowsky, Michael J; Novak, Paige J; Bailey, Jake V

2017-08-15

The Duluth Complex in northeastern Minnesota hosts economically significant deposits of copper, nickel, and platinum group elements (PGEs). The primary sulfide mineralogy of these deposits includes the minerals pyrrhotite, chalcopyrite, pentlandite, and cubanite, and weathering experiments show that most sulfide-bearing rock from the Duluth Complex generates moderately acidic leachate (pH 4 to 6). Microorganisms are important catalysts for metal sulfide oxidation and could influence the quality of water from mines in the Duluth Complex. Nevertheless, compared with that of extremely acidic environments, much less is known about the microbial ecology of moderately acidic sulfide-bearing mine waste, and so existing information may have little relevance to those microorganisms catalyzing oxidation reactions in the Duluth Complex. Here, we characterized the microbial communities in decade-long weathering experiments (kinetic tests) conducted on crushed rock and tailings from the Duluth Complex. Analyses of 16S rRNA genes and transcripts showed that differences among microbial communities correspond to pH, rock type, and experimental treatment. Moreover, microbial communities from the weathered Duluth Complex rock were dominated by taxa that are not typically associated with acidic mine waste. The most abundant operational taxonomic units (OTUs) were from the genera Meiothermus and Sulfuriferula , as well as from diverse clades of uncultivated Chloroflexi , Acidobacteria , and Betaproteobacteria Specific taxa, including putative sulfur-oxidizing Sulfuriferula spp., appeared to be primarily associated with Duluth Complex rock, but not pyrite-bearing rocks subjected to the same experimental treatment. We discuss the implications of these results for the microbial ecology of moderately acidic mine waste with low sulfide content, as well as for kinetic testing of mine waste. IMPORTANCE Economic sulfide mineral deposits in the Duluth Complex may represent the largest undeveloped source of copper and nickel on Earth. Microorganisms are important catalysts for sulfide mineral oxidation, and research on extreme acidophiles has improved our ability to manage and remediate mine wastes. We found that the microbial assemblages associated with weathered rock from the Duluth Complex are dominated by organisms not widely associated with mine waste or mining-impacted environments, and we describe geochemical and experimental influences on community composition. This report will be a useful foundation for understanding the microbial biogeochemistry of moderately acidic mine waste from these and similar deposits. Copyright © 2017 American Society for Microbiology.

High fluorescence emission of carboxylic acid functionalized polystyrene/BaTiO{sub 3} nanocomposites and rare earth metal complexes: Preparation and characterization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cao, X. T.; Showkat, A. M.; Wang, Z.

2015-03-30

Noble fluorescence nanocomposite compound based on barium titanate nanoparticles (BTO), polystyrene (PSt), and terbium ion (Tb{sup 3+}) was synthesized by a combination of surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization, Friedel-Crafts alkylation reaction and coordinate chemistry. Initially, a modification of surface of BTO was conducted by an exchange process with S-benzyl S’-trimethoxysilylpropyltrithiocarbonate to create macro-initiator for polymerization of styrene. Subsequently, aryl carboxylic acid functionalized polystyrene grafted barium titanate (BTO-g-PSt-COOH) was generated by substitution reaction between 4-(Chloromethyl) benzoic acid and PSt chains. The coordination of the nanohybrids with Tb{sup 3+} ions afforded fluorescent Tb{sup 3+} tagged aryl carboxylic acid functionalized polystyrenemore » grafted barium titanate (BTO-g-PSt-Tb{sup 3+}) complexes. Structure, morphology, and fluorescence properties of nanohybrid complexes were investigated by respective physical and spectral studies. FT-IR and SEM analyses confirmed the formation of BTO-g-PSt-Tb{sup 3+}nanohybrids. Furthermore, TGA profiles demonstrated the grafting of aryl carboxylic acid functionalized polystyrene on BTO surface. Optical properties of BTO-g-PSt-Tb{sup 3+} complexes were investigated by fluorescence spectroscopy.« less

Hafnium radioisotope recovery from irradiated tantalum

DOEpatents

Taylor, Wayne A.; Jamriska, David J.

2001-01-01

Hafnium is recovered from irradiated tantalum by: (a) contacting the irradiated tantalum with at least one acid to obtain a solution of dissolved tantalum; (b) combining an aqueous solution of a calcium compound with the solution of dissolved tantalum to obtain a third combined solution; (c) precipitating hafnium, lanthanide, and insoluble calcium complexes from the third combined solution to obtain a first precipitate; (d) contacting the first precipitate of hafnium, lanthanide and calcium complexes with at least one fluoride ion complexing agent to form a fourth solution; (e) selectively adsorbing lanthanides and calcium from the fourth solution by cationic exchange; (f) separating fluoride ion complexing agent product from hafnium in the fourth solution by adding an aqueous solution of ferric chloride to obtain a second precipitate containing the hafnium and iron; (g) dissolving the second precipitate containing the hafnium and iron in acid to obtain an acid solution of hafnium and iron; (h) selectively adsorbing the iron from the acid solution of hafnium and iron by anionic exchange; (i) drying the ion exchanged hafnium solution to obtain hafnium isotopes. Additionally, if needed to remove residue remaining after the product is dried, dissolution in acid followed by cation exchange, then anion exchange, is performed.

Methods for preparation of cyclopentadienyliron (II) arenes

DOEpatents

Keipert, Steven J.

1991-01-01

Two improved methods for preparation of compounds with the structure shown in equation X [(Cp)--Fe--(Ar)].sup.+.sub.b X.sup.b- (X) where Cp is an eta.sup.5 complexed, substituted or unsubstituted, cyclopentadienyl or indenyl anion, Ar is an eta.sup.6 complexed substituted or unsubstituted, pi-arene ligand anad X is a b-valent anion where b is an integer between 1 and 3. The two methods, which differ in the source of the cyclopentadienyl anion - Lewis acid complex, utilize a Lewis acid assisted ligand transfer reaction. The cyclopentadienyl anion ligand, assisted by a Lewis acid is transferred to ferrous ion in the presence of an arene. In the first method, the cyclopentadienyl anion is derived from ferrocene and ferrous chloride. In this reaction, the cyclopentadienyliron (II) arene product is derived partially from ferrocene and partially from the ferrous salt. In the second method, the cyclopentadienyl anion - Lewis acid complex is formed by direct reaction of the Lewis acid with an inorganic cyclopentadienide salt. The cyclopentadienyliron (II) arene product of this reaction is derived entirely from the ferrous salt. Cyclopentadienyliron (II) arene cations are of great interest due to their utility as photoactivatable catalysts for a variety of polymerization reactions.

Central effects of citral, myrcene and limonene, constituents of essential oil chemotypes from Lippia alba (Mill.) n.e. Brown.

PubMed

do Vale, T Gurgel; Furtado, E Couto; Santos, J G; Viana, G S B

2002-12-01

Citral, myrcene and limonene (100 and 200 mg/kg body wt., i.p.), constituents of essential oils from Lippia alba chemotypes, decreased not only the number of crossings but also numbers for rearing and grooming, as measured by the open-field test in mice. Although muscle relaxation detected by the rota rod test was seen only at the highest doses of citral (200 mg/kg body wt.) and myrcene (100 and 200 mg/kg body wt.), this effect was observed even at the lowest dose of limonene (50 mg/kg body wt.). Also, citral and myrcene (100 and 200 mg/kg body wt.) increased barbiturate sleeping time as compared to control. Limonene was also effective at the highest dose, and although citral did not increase the onset of sleep, it increased the duration of sleep, which is indicative of a potentiation of sleeping time. Citral (100 and 200 mg/kg body wt.) increased 2.3 and 3.5 times, respectively, the barbiturate sleeping time in mice. Similar effects were observed for myrcene and limonene at the highest dose (200 mg/kg body wt.) which increased the sleeping time around 2.6 times. In the elevated-plus maze, no effect was detected with citral up to 25 mg/kg body wt., while at a high dose it decreased by 46% the number of entries in the open arms. A smaller but significant effect was detected with limonene (5 mg/kg body wt.). While myrcene (10 mg/kg body wt.) decreased only by 22% the number of entries in the open arms, this parameter was decreased by 48% at the highest dose. Our study showed that citral, limonene and myrcene presented sedative as well as motor relaxant effects. Although only at the highest dose, they also produced a potentiation of the pentobarbital-induced sleeping time in mice, which was more intense in the presence of citral. In addition, neither of them showed an anxiolytic effect, but rather a slight anxiogenic type of effect at the higher doses.

Ferulic acid enhances IgE binding to peanut allergens in western blots.

USDA-ARS?s Scientific Manuscript database

Phenolic compounds at high concentrations are known to form insoluble complexes with proteins. We hypothesized that this complex formation could interfere with Western blot and ELISA assays for peanut allergens. To verify this, three simple phenolic compounds (ferulic, caffeic, and chlorogenic acids...

Effects of stearic acid and gamma irradiation, alone and in combination, on pasting properties of high amylose maize starch.

PubMed

Ocloo, Fidelis C K; Minnaar, Amanda; Emmambux, Naushad M

2016-01-01

The effects of stearic acid and gamma irradiation on pasting properties of high amylose maize starch (HAMS) were studied. Stearic acid (0%, 1.5%, and 5%) was added to HAMS, and then irradiated at 0, 30, and 60 kGy before pasting. Stearic acid increased the paste viscosity of un-irradiated HAMS from 420 mPas to 557 and 652 mPas for 1.5% and 5% stearic acid, respectively. This observation related well with the formation of type II amylose-lipid complexes, with melting temperatures of about 100-120 °C. Gamma irradiation (30 and 6 0kGy) reduced pasting viscosity of HAMS. Pasting of gamma irradiated HAMS resulted in the formation of type I amylose-lipid complexes, with melting temperatures and enthalpies ranging from 82 to 102 °C and 0.22 to 1.85 J/g, respectively. Stearic acid addition followed by irradiation creates means of producing different types of amylose-lipid complexes from HAMS for industrial utilization. Copyright © 2015 Elsevier Ltd. All rights reserved.

Syntheses, Characterization, Resolution, and Biological Studies of Coordination Compounds of Aspartic Acid and Glycine

PubMed Central

Akinkunmi, Ezekiel; Ojo, Isaac; Adebajo, Clement; Isabirye, David

2017-01-01

Enantiomerically enriched coordination compounds of aspartic acid and racemic mixtures of coordination compounds of glycine metal-ligand ratio 1 : 3 were synthesized and characterized using infrared and UV-Vis spectrophotometric techniques and magnetic susceptibility measurements. Five of the complexes were resolved using (+)-cis-dichlorobis(ethylenediamine)cobalt(III) chloride, (+)-bis(glycinato)(1,10-phenanthroline)cobalt(III) chloride, and (+)-tris(1,10-phenanthroline)nickel(II) chloride as resolving agents. The antimicrobial and cytotoxic activities of these complexes were then determined. The results obtained indicated that aspartic acid and glycine coordinated in a bidentate fashion. The enantiomeric purity of the compounds was in the range of 22.10–32.10%, with (+)-cis-dichlorobis(ethylenediamine)cobalt(III) complex as the more efficient resolving agent. The resolved complexes exhibited better activity in some cases compared to the parent complexes for both biological activities. It was therefore inferred that although the increase in the lipophilicity of the complexes may assist in the permeability of the complexes through the cell membrane of the pathogens, the enantiomeric purity of the complexes is also of importance in their activity as antimicrobial and cytotoxic agents. PMID:28293149

Complexes of polyadenylic acid and the methyl esters of amino acids

NASA Technical Reports Server (NTRS)

Khaled, M. A.; Mulins, D. W., Jr.; Swindle, M.; Lacey, J. C., Jr.

1983-01-01

A study of amino acid methyl esters binding to polyadenylic acid supports the theory that the genetic code originated through weak but selective affinities between amino acids and nucleotides. NMR, insoluble complex analysis, and ultraviolet spectroscopy are used to illustrate a correlation between the hydrophybicities of A amino acids and their binding constants, which, beginning with the largest, are in the order of Phe (having nominally a hydrophobic AAA anticodon), Ile, Leu, Val and Gly (having a hydrophilic anticodon with no A). In general, the binding constants are twice the values by Reuben and Polk (1980) for monomeric AMP, which suggests that polymer amino acids are interacting with only one base. No real differences are found betwen poly A binding for free Phe, Phe methyl ester or Phe amide, except that the amide value is slightly lower.

Metabolic pathway profiling of mitochondrial respiratory chain mutants in C. elegans

PubMed Central

MJ, Falk; Z, Zhang; Rosenjack; Nissim; E, Daikhin; Nissim; MM, Sedensky; M, Yudkoff; PG, Morgan

2008-01-01

C. elegans affords a model of primary mitochondrial dysfunction that provides insight into cellular adaptations which accompany mutations in nuclear gene that encode mitochondrial proteins. To this end, we characterized genome-wide expression profiles of C. elegans strains with mutations in nuclear-encoded subunits of respiratory chain complexes. Our goal was to detect concordant changes among clusters of genes that comprise defined metabolic pathways. Results indicate that respiratory chain mutants significantly upregulate a variety of basic cellular metabolic pathways involved in carbohydrate, amino acid, and fatty acid metabolism, as well as cellular defense pathways such as the metabolism of P450 and glutathione. To further confirm and extend expression analysis findings, quantitation of whole worm free amino acid levels was performed in C. elegans mitochondrial mutants for subunits of complexes I, II, and III. Significant differences were seen for 13 of 16 amino acid levels in complex I mutants compared with controls, as well as overarching similarities among profiles of complex I, II, and III mutants compared with controls. The specific pattern of amino acid alterations observed provides novel evidence to suggest that an increase in glutamate-linked transamination reactions caused by the failure of NAD+ dependent oxidation of ketoacids occurs in primary mitochondrial respiratory chain mutants. Recognition of consistent alterations among patterns of nuclear gene expression for multiple biochemical pathways and in quantitative amino acid profiles in a translational genetic model of mitochondrial dysfunction allows insight into the complex pathogenesis underlying primary mitochondrial disease. Such knowledge may enable the development of a metabolomic profiling diagnostic tool applicable to human mitochondrial disease. PMID:18178500

Medical devices; immunology and microbiology devices; classification of nucleic acid-based devices for the detection of Mycobacterium tuberculosis complex and the genetic mutations associated with antibiotic resistance. Final order.

PubMed

2014-10-22

The Food and Drug Administration (FDA) is classifying nucleic acid-based in vitro diagnostic devices for the detection of Mycobacterium tuberculosis complex (MTB-complex) and the genetic mutations associated with MTB-complex antibiotic resistance in respiratory specimens devices into class II (special controls). The Agency is classifying the device into class II (special controls) because special controls, in addition to general controls, will provide a reasonable assurance of safety and effectiveness of the device.

Stability of coordination compounds of Ni2+ and Co2+ ions with succinic acid anion in water-ethanol solvents

NASA Astrophysics Data System (ADS)

Tukumova, N. V.; Dieu Thuan, Tran Thi; Usacheva, T. R.; Koryshev, N. E.; Sharnin, V. A.

2017-04-01

Stability constants of the coordination compounds of nickel(II) and cobalt(II) ions with succinic acid anion in water-ethanol solvents are determined via potentiometric titration at ionic strength of 0.1 and at T = 298.15 K. It is found that logβ values of monoligand complexes of these ions and succinic acid anions rise along with the content of ethanol in solution ( X EtOH = 0-0.7 mole fractions). Based on an analysis of the thermodynamic characteristics of the solvation of the reagents involved in complex formation, it is found that the increased stability of succinate complexes of nickel(II) and cobalt(II) ions in water-ethanol solvents is mainly determined by the weakening of the solvation of succinic acid anion (Y2-).

Theoretical stusy of the reaction between 2,2',4' - trihydroxyazobenzene-5-sulfonic acid and zirconium

USGS Publications Warehouse

Fletcher, Mary H.

1960-01-01

Zirconium reacts with 2,2',4'-trihydroxyazobenzene-5-sulfonic acid in acid solutions to Form two complexes in which the ratios of dye to zirconium are 1 to 1 and 2 to 1. Both complexes are true chelates, with zirconium acting as a bridge between the two orthohydroxy dye groups. Apparent equilibrium constants for the reactions to form each of the complexes are determined. The reactions are used as a basis for the determination of the active component in the dye and a graphical method for the determination of reagent purity is described. Four absorption spectra covering the wave length region from 350 to 750 mu are given, which completely define the color system associated with the reactions in solutions where the hydrochloric acid concentration ranges from 0.0064N to about 7N.