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PubMedDate not supplied

[Determination of the amino acid spectrum as an aid in the up-dating of skeletal findings].

Estimation of the age of skeletal remains is usually based on subjective evaluation of the morphological grade of decomposition. This assumes, that the investigator is provided with pertinent experience. Experimentally elaborated physical and chemical methods proposed for objectification of the statements did not yet assest until today due to lacking temporal correlation. Our investigations were stimulated by observations on fossil bones indicating that the collagenbound amino acids diminish very slowly dependent on geological age. Samples of 53 skeletons of five to 2500 years were pulverized and subjected to acid hydrolysis. The amino acids released from bone collagen were separated by means of thin-layer chromatography and detected by isatin and ninhydrin reagents. The dye complexes of alanine, hydroxyproline, proline, tyrosine, and valine were measured densitometrically and quantified through calibration curves. We established, that the concentrations of the amino acids exhibited a time dependent reduction as equivalent of a loss collagen. The temporal correlation is very narrow (r less than -- 0,8) and sufficient for datings within plus/minus ten years of the more recent bones. Environmental conditions during post-mortem decay seem to have little influence on this process.

Alanine↗
PubMed1999

[Analysis of peptides from animal and plant tissues].

A new technique was developed for the analysis of peptide compositions of extracts from various animal and plant tissues. It involves the acidic extraction of a peptide fraction from the starting material and its precipitation with acetone, fractionation of peptides by ion-exchange chromatography by using a stepwise elution of fractions and detection by means of ninhydrin color reaction, and computer processing of the results. For the presentation of the results of analysis, chromatographic profiles and peptidograms were proposed. The results of analysis can be stored in a database and used for the creation of "generalized peptide portraits" and "differential peptide portraits" of the subjects investigated, which allow the identification of peptides characteristic of the subjects. The amount of peptide undergoing analysis ranged from 1 to 10 nmol.

Animals↗
PubMedDate not supplied

Quantitative analysis of sulpiride and impurities of 2-aminomethyl-1-ethylpyrrolidine and methyl-5-sulphamoyl-2-methoxybenzoate in pharmaceuticals by high-performance thin-layer chromatography and scanning densitometry.

A simple and reliable thin-layer chromatographic method for determining sulpiride and impurities of 2-aminomethyl-1-ethylpyrrolidine and methyl-5-sulphamoyl-2-methoxybenzoate was developed and validated. A methylene chloride-methanol-ammonia solution (25%; 18 + 2.8 + 0.4, v/v) solvent system is used for separation and quantitative evaluation of chromatograms. The chromatographic plate is first scanned at 240 nm to locate chromatographic zones corresponding to sulpiride and methyl-5-sulphamoyl-2-methoxybenzoate. Then 2-aminomethyl-1-ethylpyrrolidine is derivatized in situ with ninhydrin, and resulting colored spots are measured at 500 nm. The method is reproducible and convenient for quantitative analysis and purity control of sulpiride in its raw material and in its dosage forms.

Benzoates↗
PubMed1979

Isolation of a polysaccharide antigen from Schistosoma mansoni eggs.

A polysaccharide antigen was isolated from Schistosoma mansoni egg homogenates by the phenol procedure. The crude preparation (CPEA) contained at least two antigens. The more purified antigen (PEA) was isolated by sequential enzymatic treatment of CPEA with DNase, RNase, Pronase, and alpha-amylase. PEA was resistant to boiling, freezing and thawing, mild acid and alkali, and chloroform, but was destroyed with periodate. It gave a positive reaction with anthrone reagent. PEA was eluted in the wash fraction from a DEAE cellulose collumn and in the void volume of a Sephacryl 200 column. After immunoelectrophoresis and polyacrylamide electrophoresis there was little or no migration. Amino acid analysis failed to reveal ninhydrin-positive material in the a hydrolyzate of PEA. These resluts suggested that PEA is a neutral polysaccharide with a m.w. of more than 200,000 and contains no amino acids or hexosamine. Antibodies against PEA were detected in sera obtained from mice infected with S. mansoni. PEA is different from previously described antigens derived from schistosome eggs.

Animals↗
PubMed1999

[Cathepsin A activity in the aqueous humor in patients with cataract, absolute glaucoma and intraocular tumors].

PURPOSE: To evaluate cathepsin A activity in the aqueous humor of patients with cataract, absolute glaucoma and intraocular tumors. MATERIAL AND METHODS: The studies were performed on human aqueous humor taken from anterior chamber of eye balls of patients operated because of cataract, absolute glaucoma and intraocular tumors. Cathepsin A activity was determined by the ninhydrin method with synthetic substrate (N-Cbz-Phe-Ala) at its optimum pH 5.0. RESULTS: In the human aqueous humor of the eye with cataract cathepsin A activity was more than three times higher than in the eye with choroid tumors and absolute glaucoma. No differences of enzyme activity in aqueous humor between patients with glaucoma and intraocular tumors were found. CONCLUSION: The increasing proteolytic activity of cathepsin A in aqueous humor of patients with cataract suggests its importance in cataract pathogenesis. This implies that cathepsin A is involved in development of lens opacity and is found in the aqueous humor due to diffusion from cataractous lens in which the proteolytic process prevails.

Aqueous Humor↗
PubMed1999

[Cathepsin A activity in the vitreous body of patients with absolute glaucoma and intraocular tumors].

PURPOSE: To evaluate cathepsin A activity in the vitreous body of patients with absolute glaucoma and intraocular tumors. MATERIAL AND METHODS: The studies were performed on human vitreous body taken from eye balls which were enucleated because of absolute glaucoma (18 eyes) and intraocular tumors (14 eyes). Cathepsin A activity was determined by the ninhydrin method with synthetic substrate (N-Cbz-Phe-Ala) at its optimum pH 5.0. RESULTS: Cathepsin A activity in the human vitreous body in absolute glaucoma was twice as high as in intraocular tumors. CONCLUSION: Our results suggest that cathepsin A may participate in the pathogenesis of absolute glaucoma and that proteolysis may play a significant role in local destruction of the retina and the optic nerve.

Cathepsins↗
PubMed1999

Effect of glutathione L-cystein and L-djenkolic acid in the synthesis and mutagenicity of azide metabolite in Bacillus subtilis ATCC 6633 strain.

The Bacillus subtilis ATCC 6633 strain synthesizes a mutagenic metabolite from sodium azide and O-acetylserine. Mutagenicity of azide was decreased in growth media containing 10(-4) M glutathione, L-cysteine or L-djenkolic acid whereas dithiothritol (DTT) added at the same concentration did not reduce the mutagenicity of azide. Likewise, glutathione, L-cysteine, L-djenkolic acid, and DTT were found to have no effect in reducing the mutagenicity of the in vitro produced metabolite using bacterial cell-free extract. These results suggest that O-acetyl-serine sulfhydrylase catalyzes the reaction of azide and O-acetylserine to form a mutagenic metabolite, which is ninhydrin positive and migrates in TLC to an Rf value similar to that of azidoalanine in both acidic and basic solvent systems.

Bacillus subtilis↗
PubMed2000

Physiological differences for distinct somatic sensory modalities and sweating among the donor sites of cutaneous and fasciocutaneous free flaps.

Differences of sensation and sweating among the typical sites of cutaneous and fasciocutaneous flaps (scapular, lateral arm, radial forearm, groin and dorsalis pedis) were assessed in 30 healthy volunteers (20 males and 10 females) aged 17-62 years (mean 38.2 years). Standard clinical methods were used: Semmes-Weinstein monofilaments for testing light touch threshold, discriminator and blunt caliper for evaluation of static and dynamic two-point discrimination and the Marstock quantitative method for assessing the normative values of warm-cold difference limen and heat and cold pain thresholds. Spontaneous sweat secretion was observed and documented by the ninhydrin test. We established various physiological differences for distinct somatic sensory modalities and sweating among the body regions (donor sites of cutaneous and fasciocutaneous free flaps).

Adolescent↗
PubMed2000

ABTS: a safe alternative to DAB for the enhancement of blood fingerprints.

The use of 2,2'-azino-di-[3-ethylbenzthiazolinesulfonate(6)] diammonium salt (ABTS) for the enhancement of fingerprints in blood has been investigated. Optimal pH conditions and H2O2 concentrations have been determined using UV/Vis spectroscopy. ABTS is an effective and safe noncarcinogenic (though more expensive) alternative to the presently used 3,3'-diaminobenzidine (DAB) for the development of blood fingerprints, especially on porous surfaces. The bright green color of the oxidized ABTS is an advantage on certain colored surfaces where the dark brown color of DAB does not stand out well from the background. Development with ABTS does not interfere with subsequent DAB treatment, making ABTS a "nothing-to-lose" reagent. ABTS can be used after ninhydrin treatment, but the reverse is not the case.

Benzothiazoles↗
PubMedDate not supplied

Liquid chromatographic determination of lysine, methionine, and threonine in pure amino acids (feed grade) and premixes: collaborative study.

A total of 17 laboratories (including one author's laboratory) participated in a collaborative study for determination of lysine, methionine, and threonine in trade products or concentrated amino acid premixes. Thirteen samples, 4 pure amino acids and 6 premixes, including 3 Youden matched pairs, were analyzed. The applied liquid chromatographic (LC) method using cation-exchange resin and post-column derivatization with ninhydrin or o-phthaldialdehyde was shown to be accurate and specific for the analytes. Titration procedures, normally used for the assay of pure amino acids, are unspecific and the accuracy of the results can be affected by impurities. Repeatability relative standard deviations, RSDr, ranged from 0.84 to 1.17% for pure amino acids and from 0.50 to 1.68% for premixes; reproducibility relative standard deviations RSDR, ranged from 1.52 to 2.31% for pure amino acids and from 1.48 to 2.59% for premixes. Recoveries were between 97.5 and 102.8% of the expected amino acid assays. The method has been adopted Official First Action status by AOAC INTERNATIONAL.

Amino Acids↗
PubMedDate not supplied

UV/VIS spectrophotometric methods for determination of caffeine and phenylephrine hydrochloride in complex pharmaceutical preparations. Validation of the methods.

The contents of active substances were determined in a preparation TP-4 (tablets) containing paracetamol, ascorbic acid, caffeine and phenylephrine hydrochloride. For determination of caffeine and phenylephrine hydrochloride, UV/VIS spectrophotometric method was used. The VIS spectrophotometric method based on the reaction of phenylephrine with ninhydrine in sulphuric acid (1.127 kg/l). Validation of methods performed for model mixtures proved those methods were accurate, precise, repeatable and linear in the range from 50% to 150% of the amount declared in the preparation. The content of caffeine and phenylephrine hydrochloride in TP-4, Thompyrin, Panadol Extra, Ring N satisfies the FP V demands.

Caffeine↗
PubMed1977

Properties and isolation of the diffusible factor involved in Bufo arenarum fertilization.

Earlier studies have shown that a substance(s) released from the egg jelly of the toad Bufo arenarum is required for fertilization. In this paper some properties of this diffusible factor were further examined, and a procedure was designed for its isolation from crude egg extracts. The active component is soluble in water and ethanol, and insoluble in chloroform, ether and n-butanol. The biological activity is stable to liophylization and to heat, and remains unaffected after trypsin treatment. In contrast, it is impaired after treatment with ethyl acetate, 0.1 N HCl or chloroform, and is completely destroyed after converting the diffusible factor into ash. Data are presented showing that the recovery of fertilizability of extracted eggs in the bioassay system as carried out under present conditions, cannot be ascribed to a pH alteration of the insemination medium. This lends further support to the view that diffusible factor activity is not mediated through a pH effect. The factor was purified by gel chromatography coupled with desalting and paper chromatography. The active molecule is of low molecular weight and appears associated with a high pH ninhydrin-positive fraction.

Animals↗
PubMed1975

Effects of insulin, glucose, and amino acids on protein turnover in rat diaphragm.

A simple method is described for measuring rates of protein synthesis and degradation in isolated rat diaphragm. Muscles incubated in Krebs-Ringer bicarbonate buffer showed a linear rate of synthesis for 3 hours. At the same time, the muscle released tyrosine and ninhydrin-positive material, primarily amino acids, at a linear rate. This release was not a nonspecific leakage of material from the intracellular pools, but reflected net protein degradation. Tyrosine was chosen for studies of protein turnover, since it rapidly equilibrates between intracellular pools and the medium, it can be measured fluorometrically, and it is neither synthesized nor degraded by this tissue. To follow protein degradation independently of synthesis, muscles were incubated in the presence of cycloheximide. Under these conditions, the amount of tyrosine in the intracellular pools was constant, while the muscle released tyrosine at a linear rate. This tyrosine release was used as a measure of degradation. This preparation was used to study the influence of various factors known to be important for muscle growth on protein synthesis and degradation. Similar effects were obtained with diaphragms of normal and fasted rats although the latter showed decreased synthesis and increased protein degradation. Insulin by itself not only stimulated synthesis but also inhibited protein degradation (even in the presence of cycloheximide). These two effects served to reduce the net release of tyrosine from muscle protein to comparable extents. Effects of insulin on synthesis and degradation were greater when glucose was also present in the medium. Glucose by itself inhibited protein degradation but in the absence of insulin glucose had no significant effect on synthesis. Nevertheless, glucose stimulated incorporation of radioactivive tyrosine into protein, but this effect was due to an increased intracellular specific activity. Unlike glucose neither beta-hydroxybutyrate or octanoic acid had any demonstrable effects on protein degradion. The addition of amino acids at plasma concentrations both promoted protein synthesis and inhibited degradation in the diaphragm. Five times normal plasma concentrations of the amino acids had larger effects. The three branched chain amino acids together stimulated synthesis and reduced degradation, while the remaining plasma amino acids did not affect either process significantly. Thus leucine, isoleucine, and valine appear responsible for the effects of plasma amino or isoleucine and valine together, also were able to inhibit protein degradation and promote synthesis.

Amino Acids↗
PubMed1975

A new type of carbohydrate-protein linkage in a glycopeptide from normal human urine.

A glycopeptide, 3-O-beta-D-glucopyranosyl-alpha-L-fucopyranosyl-L-threonine, has been isolated from normal human urine. The glycopeptide was isolated by gel chromatography, preparative zone electrophoresis, paper chromatography, and high voltage electrophoresis. The average yield of the glycopeptide was in the range of 0.2 to 0.3 mg/liter of urine. Sugar analysis and amino acid analysis gave equimolar amounts of glucose, fucose, and threonine. Linkages and sequential order were established by methylation analysis of the glycopeptide after degradation of the amino acid residue with ninhydrin. The permethylated product was analyzed on gas liquid chromatography and mass spectrometry. Anomeric configuration was deduced from optical rotation.

Chromatography, Gas↗
PubMed1975

Continuous monitoring of radioactivity of effluent from a high-speed amino acid analyzer, with a new system of sample segmentation.

Radioactivity in the effluents from high-speed liquid chromatographic analyzers was continuously measured by use of a new sample segmentation system. To achieve highest counting efficiency, the column effluents were mixed with scintillation fluid carrying small segments of semisolid, resillient spacer. After passing through a mixer, the mixture was passed through a hollow-tube flow cell mounted in a liquid scintillation spectrometer. Because the added spacer acts like a continuous series of pistons, it unifies flow rate at center and walls of the conduit and so decreases sample carryover. This system was applied to measurement of radioactivity in the effluent of a high-speed amino acid analyzer, in which some amino acids emerge at 30-s intervals. The resulting profiles were as well resolved as were the ninhydrin-color profiles. Counting efficiencies for tritium and carbon- 14 were comparable to those obtained by static counting in vials.

Amino Acids↗
PubMed1979

Influence of anticoagulant substances on phosphoserine and taurine of human blood.

The influence of heparine (Liquemin) and sodium-EDTA on phosphoserine and taurine of human blood was investigated. Phosphoserine which was not or nearly not present in serum increased after addition of both the anticoagulant substances. The heparine used contained phosphoserine as the only ninhydrinic substance in low concentrations. After addition of heparine phosphoserine in human plasma does not increase proportionally to that change. A mechanism is assumed which leads to the release from cells or which stimulates the synthesis of the substance. A similar effect was found with sodium-EDTA but not with sodium citrate. An opposite effect was detected with taurine in human blood. In serum the highest concentration was measured which decreased slowly under heparine as well as under sodium-EDTA addition.

Anticoagulants↗
PubMed1975

Quantitative method for estimating fecal amino acids.

We describe a method for quantitatively estimating 24 ninhydrin-reacting substances, including the commoner amino acids, in fecal dialysate prepared from ingested dialysis bags retrieved from fresh stool. It is accurate to 2 mumol of alpha-amino nitrogen per liter of fecal dialysate, and for most substances recovery of added standards is 100%. It involves dilution, ultrafiltration, and automated ion-exchange column chromatography of the dialysate. Some normal values are provided.

Adult↗
PubMed2001

Luminescent visualization of latent fingerprints by direct reaction with a lanthanide shift reagent.

The utilization of the lanthanide shift reagent tris (6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionato) europium (III) [Eu(fod)3] as a simple one-step reagent for the luminescent visualization of latent fingerprints has been investigated. UV excitation of Eu(fod)3-treated prints, achieved by using a hand-held UV lamp or a Polilight, results in an orange emission at 614 nm. Time-resolved imaging is not required for visualization. Visualization of latent fingerprints on paper under the conditions used, although good, was found to be inferior to that obtained by standard DFO (1,8-diazafluoren-9-one) treatment, whereas visualization of prints obtained on aluminum drink cans and galvanized iron proved superior to that obtained by Superglue/panacryl treatment. Eu(fod)3 treatment can also be used first without compromising subsequent ninhydrin or DFO treatment, making it a 'nothing-to-lose" reagent.

Aluminum↗