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PubMed2001

Speciation of rare earth elements in soil by sequential extraction then HPLC coupled with visible and ICP-MS detection.

The distribution of rare earth elements (REE) in a pooled soil sample collected from Zhangzhou, Fujian Province, China, was screened by a five-step sequential extraction procedure coupled with ICP-MS determination after preconcentration of REE and removal of the matrix by extraction with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (HPMBP). The results showed that the distribution of REE in the different fractions of the pooled soil sample studied followed the order soluble species (46.76%) > species bound to organic matter (22.08%) > species in the residue (16.77%) > species bound to Fe-Mn oxides (2.02%). An effective method for speciation of REE, which utilized weak cation-exchange HPLC separation hyphenated with post-column derivatization and visible or on line ICP-MS detection, was, moreover, developed and successfully applied to the speciation of REE in the soluble extract of the pooled soil sample. The stability of known complexes of lanthanum during the HPLC separation was investigated with fluoride, citrate, and ethylenediamine tetraacetic acid (EDTA) chosen as ligands modeling those in the soil. REE in the soluble extract of the pooled soil sample were subsequently classified into three types of species--< or = +1 charged complexes (negatively charged, neutral, and +1 charged), +2 charged complexes, and "free" REE species. This method is expected to be useful for identification of bioavailable (or toxic) species of REE in environmental samples.

Journal Article↗
PubMed1998

Drug use in Estonia in 1994-1995: a follow-up from 1989 and comparison with two Nordic countries.

OBJECTIVE: To determine the patterns of drug use in Estonia for the years 1989 and 1994 1995, i.e. for the years before and after the pharmaceutical services in the country changed from a state monopoly to a competitive market. METHODS: The wholesale data from Estonia and the defined daily doses methodology were used. For comparison, national statistics on medicines from Finland and Sweden for the years 1994-1995 are shown. RESULTS: The general sales of drugs in Estonia decreased almost twofold in all major pharmacological groups from 1989 to 1994 and subsequently increased by 10%-30% in 1995. Substantial differences in patterns of drug use between Estonia and the two Nordic countries were observed. The amount of prescription-only medicines used in Estonia was approximately 25% of that used in Finland and Sweden. The amount of over-the-counter drugs used was 61% of that used in Finland and 58% of that used in Sweden. In the drug use patterns in Estonia, some common trends can be noted: (1) persistent traditions, such as the low use of diuretics, beta-blockers, antithrombotics and inhalant anti-asthmatic drugs; (2) changes in prescription preferences--central anti-adrenergic drugs, pyrazolones, aminoglycosides and barbiturates are being replaced by calcium channel blockers and angiotensin-converting-enzyme inhibitors, propionic acid derivatives, cephalosporins and benzodiazepines, respectively; (3) rapidly increasing use of drugs not prescribed in the 1980s, such as hormonal contraceptives, opioids and antiulcer drugs, which strongly improves the quality of pharmacotherapy in Estonia. CONCLUSION: The general trends in Estonia and the two Nordic countries are similar--the use of newer and more effective drugs is increasing and that of older ones decreasing. The changes are more rapid in Estonia than in Finland and Sweden, but, because of a short observation period, the use of newer drugs not yet prevailing. The international differences in drug utilization observed in this study may possibly be related mainly to the prescription preferences (e.g. therapeutic traditions) and less dependent on the respective health care systems (e.g. reimbursement schemes) and economic state of the country.

Drug Prescriptions↗
PubMed1983

History of antipyretic analgesic therapy.

The use of naturally occurring plant materials for the relief of pain dates back to 3,000 B.C., although rapid advances in antipyretic analgesic therapy have been made more recently. Salicylic acid was synthesized in 1860, and the pyrazolone group, first represented by antipyrine, in 1883. Phenacetin was developed in 1886. Acetaminophen has been in use since the 1890s.

Acetaminophen↗
PubMed1983

Prostaglandins and the mode of action of antipyretic analgesic drugs.

Antipyretic analgesics account for more than 95 percent of the analgesic market. The most important agents of this group--salicylates, aniline derivatives such as acetaminophen, and nonacidic pyrazolones--have been used for almost 100 years. Nevertheless, their therapeutic mechanisms and the molecular causes of the most important side effects remain unclear. Several common theories are discussed and challenged.

Animals↗
PubMed1983

Review of comparative antipyretic activity in children.

Fever is one of the most common medical complaints referred to physicians for diagnosis and therapy. In addition, consumers frequently medicate themselves for fever associated with common, self-limited illnesses. The pathogenesis of fever suggests that pharmacologic therapy, which lowers the hypothalamic set-point, is an essential element in treatment. Not all fevers need to be treated; however, when indicated, therapy with antipyretics is necessary. The major antipyretic agents, acetaminophen, aspirin, and pyrazolone derivatives, are equally effective in reducing fever. However, after comparing side effects and risks of toxicity, acetaminophen may be the preferred agent in children.

Acetaminophen↗
PubMed1983

Hematologic effects of antipyretic analgesics. Drug-induced agranulocytosis.

Drug-induced agranulocytosis may be type I (involving the drug, antibodies and neutrophils), type II (associated with accumulated drug toxicity in hypersensitive persons), or type III (representing different etiologies induced by immune and toxic mechanisms). The pyrazolones (amidopyrine, dipyrone and butazones), phenothiazine derivatives, antithyroid drugs, and antibiotics are thought to be causative agents in agranulocytosis. The symptoms may involve sudden onset of high fever, sore throat with ulcerative angina, or stomatitis. Diagnosis of agranulocytosis is confirmed by severe granulocytopenia (0-0.5 X 10(9)/l), but bone marrow examination is required to rule out aplastic anemia and cancer. Treatment of drug-induced agranulocytosis involves immediate withdrawal of the incriminated drug. In most patients, granulocyte, reticulocyte, and thrombocyte cell counts overshoot in the regenerative phase of drug-induced agranulocytosis.

Agranulocytosis↗
PubMed1983

Analgesics during pregnancy.

The thalidomide tragedy of the late 1950s clearly proved the need for caution, and questionable drug use should always be avoided. The teratogenic potential of a drug is related to dosage and time of administration. During blastogenesis, fetal death may occur; during embryogenesis, deformity may develop; and during the last trimester, functional anomalies or "covert embryopathy" may be seen. Finally, the benefit to risk ratio of every drug must be carefully weighed, and only those with proved safety to the feto-maternal unit should be prescribed. Aspirin may be administered to the pregnant woman as an anti-inflammatory agent but in the lowest therapeutic dosage. In the later stages of pregnancy, however, aspirin should be avoided since it may prolong labor, lead to greater blood loss during delivery, and increase the incidence of stillbirths. The pyrazolones, although not associated with teratogenic side effects, may lead to sometimes fatal agranulocytosis and, accordingly, are not recommended in pregnancy. Acetaminophen is the analgesic and antipyretic of choice during all phases of pregnancy.

Acetaminophen↗
PubMed1983

Interactions of analgesics with other drugs.

Antipyretic analgesics, such as salicylates, acetaminophen, and pyrazolones, are often given concomitantly with a variety of other drugs. Drug interactions that occur at the receptors are known as pharmacodynamic interactions; alterations in absorption (bioavailability), distribution (plasma protein-binding), and elimination (renal excretion, hepatic metabolism) are termed pharmacokinetic interactions. For example, antacids and food both delay the absorption of analgesics. Highly protein-bound drugs (such as phenylbutazone, phenytoin, or warfarin) can compete with the common binding sites of salicylates. Hepatic elimination of salicylates can be influenced by drugs such as beta-blockers and cimetidine. Clinically important interactions involving salicylates, acetaminophen, and other antipyretic analgesics are discussed.

Acetaminophen↗
PubMed1989

Substrates for arachidonic acid co-oxidation with peroxidase/hydrogen peroxide. Further evidence for radical intermediates.

We tested the ability of a wide variety of organic compounds, including benzene and phenol derivatives, aromatic amines, pyrazoline derivatives and other non-steroidal anti-inflammatory drugs, to act as cosubstrates during the horseradish peroxidase/hydrogen peroxide-mediated oxygenation of arachidonic acid. Structural requirements for drug activation in our system proved to be an aromatic system and ring substitution by an easily oxidizable group. Complementary substituents modified drug activation. Among the phenol derivatives and aromatic amines we found the meta-substituted compounds to be significantly more effective than their ortho- and para-substituted analogues, indicating the involvement of radical intermediates in this type of reaction. The radical from 1-phenyl 3-methyl 2-pyrazolone(5) was detected by electron paramagnetic resonance spectroscopy. Kinetic studies on this radical were in good accordance with time-dependent measurement of arachidonic acid oxygenation.

Arachidonic Acid↗
PubMed1985

Determination of unsulfonated aromatic amines in FD&C Yellow No. 6 by the diazotization and coupling procedure followed by reversed-phase high-performance liquid chromatography.

Data are presented for the determination of parts-per-billion (10(9)) levels of aniline, benzidine, 4-aminobiphenyl (4-ABP) and 4-aminoazobenzene in the regulated color additive FD&C Yellow No. 6. The determination involves chloroform extraction of the amines from the color additive, followed by diazotization and coupling with the disodium salt of 3-hydroxy-2,7-naphthalenedisulfonic acid (R-salt). The coupling products are then analyzed by reversed-phase high-performance liquid chromatography. An interference discovered during the determination of 4-ABP required the use of 4,5-dihydro-5-oxo-1-(4-sulfophenyl)-1H-pyrazole-3-carboxylic acid (pyrazolone-T) as an alternative coupling agent. The identity of each coupling product is confirmed by obtaining a UV-visible spectrum of the eluting solute. The liquid chromatograph is calibrated in the presence of the color additive by using the external standard method.

Amines↗
PubMed1996

Separation of neutral carbohydrates by capillary electrophoresis.

The basic strategies for analysis of neutral carbohydrates by capillary electrophoresis are summarized. Neutral carbohydrates are dissociated in strong alkali to give anions, hence they can be separated directly by zone electrophoresis based on the difference between their dissociation constants. However, neutral carbohydrates are not electrically charged under normal conditions. Therefore, they should be converted to ions prior to or during analysis. Precapillary introduction of a basic or an acidic group to a neutral carbohydrate gives the derivative positive (in acidic media) or negative (in alkaline media) charge, respectively. The derivatives thus obtained can be separated by zone electrophoresis. Analysis of carbohydrates in a carrier containing an oxyacid salt (such as sodium borate) or an alkaline metal salt (such as calcium acetate) causes in situ conversion to anionic or cationic complexes, respectively, which are separated by zone electrophoresis. The effective uses of electrokinetic chromatography in sodium dodecyl sulfate micelles for hydrophobic derivatives (such as 1-phenyl-3-methyl-5-pyrazolone derivatives) and size-exclusion electrophoresis in gel-packed capillaries for size-different oligosaccharides are also discussed. Each separation mode has its inherent method(s) for detection, which are also described here.

Carbohydrate Sequence↗
PubMed1986

Activation of inhibition from the periaqueductal grey matter mediates central analgesic effect of metamizol (dipyrone).

The pyrazolone derivative, metamizol (dipyrone), possesses analgesic, antipyretic, anti-inflammatory and spasmolytic properties. It is often classified as peripherally acting. To test the possibility that a central action of the drug contributes to its antinociceptive and analgesic effects, experiments were carried out in which the tail-flick response to radiant heat, flexor reflex activity in the tibialis anterior muscle and activity in ascending spinal axons evoked by stimulation of afferent C fibres in the sural nerve, and activity of neurones in the periaqueductal grey matter and the substantia nigra were assessed in rats. Metamizol administered by intraperitoneal (i.p.; 10, 20 and 40 mg/kg) or intrathecal (i.t.; 50 to 400 micrograms) injection to intact rats dose-dependently prolonged the tail-flick latency. Administration by i.t. injection to spinal rats was without effect. Intravenous (i.v.) injection of metamizol (140 mg/kg) reduced flexor reflex activity in intact animals, while an i.t. injection to spinal rats was ineffective at a low dose (100 micrograms) or enhanced the reflex activity at a higher dose (400 micrograms). Activity in ascending axons responding to afferent C fibre stimulation was mostly depressed by i.t. injection of metamizol (40, 80 and 140 mg/kg) in rats with an intact spinal cord. Ascending activity was increased by i.t. injection of the drug (100 and 200 micrograms) to spinal rats. Metamizol (140 mg/kg) i.v. increased the activity of neurones in the PAG and reduced that of neurones in the substantia nigra. Metamizol administered by microinjection into the PAG prolonged the tail-flick latency (15-100 micrograms) and depressed C fibre-evoked activity in ascending axons (100 micrograms). The results suggest that a central action is involved in the analgesic effect of metamizol and that this central action manifests itself by an activation of inhibition originating in the PAG.

Action Potentials↗
PubMed1988

Cyanide distribution in five fatal cyanide poisonings and the effect of storage conditions on cyanide concentration in tissue.

The cyanide distribution in five fatal cyanide poisonings was analyzed by the pyridine-pyrazolone method using a Conway diffusion cell. In order to study the effect of storage conditions on cyanide concentration in tissue samples, the cyanide concentrations were first measured immediately after collection of the samples at autopsy, then measured again after storage in a refrigerator (4 degrees C) or in a freezer (-20 degrees C) for periods ranging from 1 day to 3 weeks. Concentrations in all but three of the blood samples stored at 4 degrees C or -20 degrees C increased, with concentration ratios based on measurement made before and after storage ranging from 0.71 to 1.46. The concentrations in the liver, kidney, and brain samples either increased or decreased, with ratios of from 0.2 to 8.8. The concentrations in the stomach contents samples decreased rapidly at 4 degrees C, but hardly changed at all at -20 degrees C.

Adult↗
PubMed1996

High-performance liquid chromatographic mapping of the oligosaccharides released from the humanised immunoglobulin, CAMPATH 1H.

A sensitive and reproducible method for the routine mapping of oligosaccharides in a humanised immunoglobulin (IgG) is described. The method involves the enzymic release of intact glycans using the endoglycosidase glycopeptidase-F, and subsequent derivatisation with 1-phenyl-3-methyl-5-pyrazolone to facilitate analysis by high-performance liquid chromatography (HPLC). The heterogeneous oligosaccharide chains are separated by a phosphate buffer-acetonitrile gradient reversed-phase HPLC method and monitored by ultraviolet detection at 245 nm, allowing the detection of picomole amounts. A number of standard oligosaccharides are similarly derivatised to enable classification of the types of structures present from a comparison of retention times.

Alemtuzumab↗
PubMed1995

Disaccharide analysis of the skin glycosaminoglycans in chronically ultraviolet light-irradiated hairless mice.

The alteration of main disaccharide units in the skin of hairless mice (HOS:Hr 1) after chronic and repeated ultraviolet light (UV) radiation was investigated using high performance liquid chromatography after labeling with 1-phenyl-3-methyl-5-pyrazolone. The total amount of main disaccharide units increased by UVA irradiation at the 24th and 36th weeks in comparison with the control. At the 36th week UVA significantly increased hyaluronic acid-derived delta Di-HA (HA). Dermatan sulfate-derived delta Di 4S (DS) and chondroitin sulfate-derived delta Di-4S (CS) increased at the 36th week, although not statistically significant. The total amount of main disaccharide units was increased significantly by UVB irradiation at the 24th week as compared with the control. Concerning the compositional change in main disaccharide units after a 36-week repeated exposure, the decrease in delta Di-HA(HA) and the increase in delta Di-4S (DS) were found in the order of control, UVA- and UVB-irradiated groups. These results, for the first time, indicate the precise alterations of glycosaminoglycans, both in the total amount and in the composition, confirming the previous histochemical findings. This disaccharide analysis should provide a useful method to examine the biochemical changes of skin glycosaminoglycans in photoaging.

Animals↗
PubMed1996

Disaccharide analysis of human skin glycosaminoglycans in sun-exposed and sun-protected skin of aged people.

The total amount of main disaccharide units of skin glycosaminoglycans was compared between sun-exposed (n = 12) and sun-protected skin (n = 14) of aged people using high performance liquid chromatography after labeling with 1-phenyl-3-methyl-5-pyrazolone. The total amount of main disaccharide units in sun-exposed skin was comparable to sun-protected skin presumably due to the diversity of individuals. Consequently, we compared sun-exposed skin with sun-protected skin in identical individuals (n = 6). The total amount of main disaccharide units in sun-exposed skin was significantly greater than that in sun-protected skin (P < 0.05). In addition, the ratio of delta Di-HA (hyaluronic acid, HA)/delta Di-4S (dermatan sulfate, DS) in sun-exposed skin showed a decreasing trend as compared with sun-protected skin in four of six individuals. These results are in agreement with our previous results obtained in animal experiments of photoaging, i.e., hairless mouse skin exposed to repeated UV irradiation showed an increase in total amount of main disaccharide units and a decrease in the ratio of delta Di-HA(HA)/delta Di-4S(DS). We could confirm similar changes in skin glycosaminoglycans both in human and murine photoaging supporting the appropriate rationale for using the hairless mouse as an animal model for photoaging. Again, disaccharide analysis should provide a useful method to examine the biochemical changes of skin glycosaminoglycans in human photoaging.

Aged↗
PubMed2005

Profiling oligosaccharidurias by electrospray tandem mass spectrometry: quantifying reducing oligosaccharides.

A method to semiquantify urinary oligosaccharides from patients suffering from oligosaccharidurias is presented. 1-Phenyl-3-methyl-5-pyrazolone has been used to derivatize urinary oligosaccharides prior to analysis by electrospray ionization-tandem mass spectrometry (ESI-MS/MS). Disease-specific oligosaccharides were identified for several oligosaccharidurias, including GM1 gangliosidosis, GM2 gangliosidosis, sialic acid storage disease, sialidase/neuraminidase deficiency, galactosialidosis, I-cell disease, fucosidosis, Pompe and Gaucher diseases, and alpha-mannosidosis. The oligosaccharides were referenced against the internal standard, methyl lactose, to produce ratios for comparison with control samples. Elevations in specific urinary oligosaccharides were indicative of lysosomal disease and the defective catabolic enzyme. This method has been adapted to enable assay of large sample numbers and could readily be extended to other oligosaccharidurias and to monitor oligosaccharide levels in patients receiving treatment. It also has immediate potential for incorporation into a newborn screening program.

Carbohydrate Sequence↗
PubMed2005

Influence of the labeling group on ionization and fragmentation of carbohydrates in mass spectrometry.

The ionization and fragmentation behaviors of carbohydrate derivatives prepared by reaction with 2-aminobenzamide (AB), 1-phenyl-3-methyl-5-pyrazolone (PMP), and phenylhydrazine (PHN) were compared under identical mass spectrometric conditions. It has been shown that the intensities of signals in MS spectra depend on the kind of saccharides investigated and reducing end labels used. PMP sialyllactose, when ionized by ESI/MALDI, produced a mixture of [M + H]+, [M + Na]+, [M - H + 2Na]+ ions in the positive mode and [M - H]-, [M + Na - 2H]- ions in the negative mode. The AB and PHN derivatives formed abundant [M + H]+ and [M - H]- ions in ESI, and by matrix-assisted laser desorption/ionization (MALDI) produced abundant [M + Na]+ ions. PMP- and reduced AB-sialyllactose produced only Y-type fragment ions under both MS/MS sources. In the electrospray ionization (ESI)-MS/MS spectrum of PHN-sialyllactose, abundant ions corresponded to B, Z cleavages and in its MALDI-MS/MS spectrum, the abundant ions were consistent with Y glycosidic cleavages with the concurrence of B, C, and cross-ring fragment ions. In the MALDI-MS spectra of oligosaccharides acquired immediately after derivatization, it was possible to detect only PHN derivatives. After purification, spectra of all three types of derivatives showed high signal-to-noise ratios with the most abundant ions observed for AB reduced saccharides. [M + Na]+ ions were the dominant products and their fragmentation patterns were influenced by the type of the labeling and the kind of oligosaccharide considered. In the MALDI-PSD and -MS/MS spectra of AB-derivatized glycans, higher m/z fragment ions corresponded to B and Y cleavages and the loss of bisecting GlcNAc appeared as a weak signal or was not detected at all. Fragmentation patterns observed in the spectra of hybrid/complex PHN and PMP glycans were more comparable-higher m/z fragments corresponded to B and C glycosidic cleavages. For PHN glycans, the abundance of ions resulting from the loss of bisecting GlcNAc depended on the number of residues linked to the 6-positioned mannose. Also, PHN and PMP derivatives produced cross-ring cleavages with abundances higher than observed in the spectra of AB derivatized oligosaccharides. For high-mannose glycans, the most informative cleavages were provided by AB and PHN type of labeling. Here, PMP produced dominant Y-cleavages from the chitobiose while other ions produced weak signals.

Antipyrine↗