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PubMed1989

Bacteria and inflammatory cells reduce chorioamniotic membrane integrity and tensile strength.

Bacteria and the inflammatory response they engender are implicated in the pathophysiology of premature rupture of fetal membranes and preterm birth. We tested the hypothesis that bacteria and polymorphonuclear neutrophils may have both separate and combined effects in weakening the amniochorionic membrane, and thus predispose to premature rupture of membranes. We examined how three parameters of membrane integrity (bursting tension, work to rupture, and elasticity) were affected by standardized preparations (10(9) cfu/mL) of group B streptococci or Staphylococcus aureus in the presence or absence of purified human neutrophils (32 x 10(6)/mL). In addition, effects of purified human neutrophil elastase were evaluated. Exposure to either group B streptococcus or S aureus decreased membrane strength, elasticity, and work to rupture. Only activated neutrophils had significant effects on membrane strength. Membrane exposure to S aureus plus neutrophils led to an additive weakening of fetal membranes. On the other hand, group B streptococci did not interact with neutrophils to yield a significant further weakening of the membranes. Elastase (150 U/mL) also weakened the membrane. The results were correlated with measures of protease (Azocoll and ninhydrin assays) and peroxidase (dimethoxybenzidine) activity. Our findings support the concept that human neutrophils and their constituent enzymes may act in concert with bacteria and their protease(s) in weakening amniochorion, and may possibly predispose to premature rupture of membranes in some women. These observations require clinical correlations.

Endopeptidases↗
PubMed1989

[Changes in the serum levels of lactate dehydrogenase, gamma- glutamyltransferase, glucose and alpha amino nitrogen in guinea pigs with experimental ascariasis].

The studies were carried out on 90 male guinea pigs of which 75 were infected per os with a dose of ca. 5000 invasive eggs of Ascaris lumbricoides suis. At the 1st, 2nd, 4th, 7th and 20th day of infection blood was taken from experimental and control animals. The activity of LDH and its liver fraction (spectrophotometric method), GGTP (circle test method) was determined. The level of glucose (orthotoluidin method) and alpha amino nitrogen (ninhydrin method was determined. In the course of larval ascariasis an increase in the values of the studied parameters was noted, especially at the 4th and 7th day of infection. The changes in the activity of the studied enzymes evidence disturbances of the structure and function of the liver of infected animals. The increased level of glucose and alpha amino nitrogen is probably associated with a disturbance of basic energy metabolism of the host organism.

Animals↗
PubMed1985

Free amino acids production by ectomycorrhizal fungi of pine (Pinus sylvestris L.).

Studies on free amino acids production by five species of ectomycorrhizal fungi (Amanita muscaria, Suillus granulatus, Suillus luteus, Suillus bovinus and Rhizopogon luteolus) show that all the fungi produced mainly: glutamic acid, leucine, lysine, ornithine, arginine and an unidentified ninhydrin-positive compound X3. Both the quality and quantity of amino acids released was different in the fungal species studied. The predominant amino acids in post-culture liquids in general did not exceed 1.5 micrograms/mg dry mass.

Agaricales↗
PubMed1979

Manual fluorometry of phenylalanine from blood specimens collected on filter paper: a modified procedure.

In this manual fluorometric method, blood samples are used that have been impregnated on the filter paper, a convenient collection technique that is widely used to screen newborns for phenylketonuria. The modified procedure, based on the method of McCaman and Robins [J. Lab Clin. Med. 59, 885 (1962)], includes elution of phenylalanine from specimens on filter paper, removal of proteins by precipitation with trichloroacetic acid at 0 degrees C, and then reaction with ninhydrin-peptide reagent for color development. The standard curve is linear to at least 200 mg/L and the CV is 6.3% for a phenylalanine concentration of 27 mg/L. The modified procedure is suitable both for early screening for phenylketonuria and for monitoring blood phenylalanine of phenylketonurics during dietary therapy.

Blood Specimen Collection↗
PubMed1989

Distribution of ciliatine (2-aminoethylphosphonic acid) and phosphonoalanine (2-amino-3-phosphonopropionic acid) in human tissues.

Ciliatine (2-aminoethylphosphonic acid) was detected in the human brain, heart, kidney, liver, intestine, spleen, adrenal glands, and aorta. Phosphonoalanine (2-amino-3-phosphonopropionic acid) was found in the human liver, intestine and spleen. Tissue homogenates were extracted with trichloroacetic acid and a chloroform-methanol mixture. After hydrolysis, each fraction was subfractionated by ion-exchange chromatography and examined by paper chromatography and electrophoresis using a specific ninhydrin-molybdate staining procedure to detect the phosphonic acids. The acids were found bound either to lipid or to protein; no free phosphonic acid was detected.

Adrenal Glands↗
PubMed1989

[Histochemical properties of secretory granules and fine structure of terminal portion in the Japanese Macaque labial gland].

The terminal portion of the Japanese macaque (Macaca fuscata) labial gland was examined ultrastructurally and histochemically. The results obtained are as follows. 1) The Japanese macaque, Macaca fuscata has the upper and the lower labial glands, which can be described as a compound tubulo-acinar gland. 2) The terminal portion of the labial gland appears to be consisted of the mucous acini and the demilunes when examined with the light microscope. 3) The secretory granules containing in the glandular cells of the mucous acini and the demilunes are negative with napthol yellow S, ninhydrin-Schiff and DMAB nitrite. 4) The secretory granules containing in the glandular cells of mucous acini stain intensely with PAS, alcian blue (pH1.0, 2.5, 3.5), colloidal iron and PA-methenamine silver, while those of demilunes are negative with alcian blue (pH1.0). The glandular cells of demilune with the PA-methenamine silver method shows weak positive granules and positive granules which are limited to the hallo of them. 5) In the mucous acini the mucous granules are ejected from glandular cells by the process of exocytosis. 6) The myoepithelial cell can be seen in the terminal portion. This cell surrounds the acini with long processes. These findings suggest that the glandular cells of the demilune have the granules containing mucopoly saccharides and a small quantity of protein in addition to the mucous granules, although the terminal portion of the Japanese macaque labial gland is nearly composed of mucous cells.

Animals↗
PubMed1989

Proteolytic fragmentation and peptide mapping of human carboxyamidomethylated tracheobronchial mucin.

Human tracheobronchial mucin was isolated from lung mucosal gel by chromatography on Sepharose 4B in the presence of dissociating and reducing agents, and its thiol residues were carboxyamidomethylated with iodo[1(-14)C]acetamide. The 14C-carboxyamido-methylated mucin was purified by chromatography on Sepharose 2B. No low molecular weight components were detected by molecular sieve chromatography or polyacrylamide gel electrophoresis in the presence of dissociating and reducing agents or by analytical density centrifugation in CsCl/guanidinium chloride. After digestion of the purified 14C-mucin with trypsin-L-1-tosylamido-2-phenylethyl chloromethyl ketone, three fractions (TR-1, TR-2, and TR-3) were observed by chromatography on Sepharose 4B. TR-1, a 260-kDa mucin glycopeptide fragment, contained all of the neutral hexose and blood group activity and 20% of the radioactivity in the undigested mucin. TR-1 was refractory to a second incubation with trypsin but could be digested by papain or Pronase to a smaller mucin glycopeptide fraction, as judged by the slight decrease in apparent molecular weight on Sepharose CL-4B. These mucin glycopeptides contained approximately 50% of the radioactivity in the TR-1 fraction, indicating that the glycosylated domains of carboxyamidomethylated tracheobronchial mucin contained thiol residues. The remainder of the radioactivity from papain or Pronase digests of TR-1 eluted, like the TR-3 fractions, in the salt fraction on Sepharose CL-4B. Peptide mapping of the nonglycosylated TR-3 fraction by TLC and high voltage electrophoresis yielded six principal and several less intensely stained ninhydrin reactive components, with the radiolabel concentrated in one of the latter peptides. Peptide purification of the TR-3 fraction by high pressure liquid chromatography on a C18 reverse phase column demonstrated the presence of four major peptides, with TR-3A being the dominant component. The TR-3D peptide contained S-carboxy-aminomethylcysteine and had 69% sequence similarity to the sgs-7 salivary glue protein of Drosophila.

Amino Acids↗
PubMedDate not supplied

Liquid chromatographic method for quantitation of glyphosate and metabolite residues in organic and mineral soils, stream sediments, and hardwood foliage.

A liquid chromatographic method for determining glyphosate (GLYPH) and its major metabolite aminomethylphosphonic acid (AMPA) in various environmental substrates is described. Ion-exchange column chromatography is coupled with post-column ninhydrin derivatization and absorbance detection at 570 nm. Use of a valve-switching technique allowed quantitation of both analytes in a single chromatographic run and eliminated slow-eluting, coextracted interferences. The method was successfully used to quantitate GLYPH and AMPA in organic and mineral soils, stream sediments, and foliage of 2 hardwood brush species. Mean recovery efficiencies for GLYPH as determined from fortified blank field samples were as follows: bottom sediment 84%, suspended sediment 66%, organic soils 79%, mineral soils 73%, alder leaf litter 81%, salmonberry leaf litter 84%, and artificial deposit collectors 87%. Precision for GLYPH determination was good with less than 14% coefficient of variation on mean recovery for all substrates. Limits of detection were lowest for sediments (0.01 microgram/g dry mass) and highest for foliage substrates (0.10 microgram/g dry mass). Using this system, 6 samples/person/day were routinely analyzed.

Chromatography, High Pressure Liquid↗
PubMed1987

Nourseothricin (streptothricin) inactivated by a plasmid pIE636 encoded acetyl transferase: nature of the inactivated nourseothricin.

Nourseothricin, a mixture of several streptothricins, is inactivated by an acetyl transferase produced by Escherichia coli containing the plasmid pIE636. Nourseothricin inactivated in the presence of 14C-acetate was purified and submitted to partial hydrolysis. In the hydrolysate besides others a radioactive and ninhydrin-reactive substance moving only slightly towards the cathode was found. It proved to be [14C]-acetyl beta-lysine.

Acetylation↗
PubMedDate not supplied

Glutathione conjugates. Immobilized enzyme synthesis and characterization by fast atom bombardment mass spectrometry.

Glutathione transferase activity was shown to be present in an immobilized preparation of microsomal protein. Chlorodinitrobenzene, ethacrynic acid, captopril, styrene oxide, and iminocyclophosphamide were found to be substrates, each providing a different kind of electrophilic functional group for conjugation. The glutathione conjugates were characterized by thin layer chromatography (visualized by reaction with ninhydrin) and by high pressure liquid chromatography. A variety of conditions was evaluated for analysis of these glutathiones by fast atom bombardment mass spectrometry.

Animals↗
PubMed1986

[Blood levels of nitrogenous substances in dairy cows with high and low production].

In blood serum of dairy cows of the Slovak Pied breed with high and low performance, the levels of total protein, urea, amino nitrogen, non-protein nitrogen and uric acid were studied over the period of four to six weeks after calving. Total protein was determined by the Bio-La-test, amino nitrogen by means of ninhydrin, non-protein nitrogen by Berthelot agent and uric acid by Benedict agent. In comparison with dairy cows with low performance, the dairy cows with high performance had a statistically significantly higher level of total protein, urea, amino nitrogen and non-protein nitrogen. The differences in uric acid content were statistically insignificant.

Animals↗
PubMed1988

N6-(1-carboxyethyl)lysine formation by Streptococcus lactis. Purification, synthesis, and stereochemical structure.

During growth in an arginine-deficient (chemically defined) medium, cells of Streptococcus lactis K1 formed significant amounts of a previously undetected ninhydrin-positive compound. This intracellular compound did not cochromatograph with any of a wide range of amino acids or amino acid analogs tested. However, by two-dimensional thin layer chromatography, the unknown compound migrated close to the recently discovered N5-(1-carboxyethyl)ornithine (Thompson, J., Curtis, M. A., and Miller, S. P. F. (1986) J. Bacteriol. 167, 522-529; Miller, S. P. F., and Thompson, J. (1987) J. Biol. Chem. 262, 16109-16115). The purified compound behaved as a neutral amino acid and eluted between valine and methionine in the amino acid analyzer. The results of 1H NMR spectroscopy suggested the presence of a lysine backbone and a coupled methyl-methine unit in the molecule, and 13C NMR showed that there were nine carbon atoms, of which two (C-1 and C-7) were carboxyl carbons. The simplest structure compatible with the physicochemical data was that of an alkylated derivative of lysine. The identity of this new amino acid, N6-(1-carboxyethyl)lysine, was confirmed by chemical synthesis. In vivo labeling experiments conducted using L[U-14C]lysine and [epsilon-15N]lysine showed that exogenous lysine served as the precursor of intracellular N6-(1-carboxyethyl)lysine and that the epsilon-amino N atom was conserved during biosynthesis of the lysine derivative. Of the two possible diastereomers (2S,8S or 2S,8R) of N6-(1-carboxyethyl)lysine, comparative 13C NMR spectroscopy established that the amino acid produced by S. lactis K1 was exclusively of the 2S,8S configuration.

Amino Acids↗
PubMedDate not supplied

[An optimal method of determining the level of cathepsin A in blood platelet homogenates].

Blood platelet cathepsin A hydrolyzes Cbz-Glu-Tyr most intensively at pH 5.0, it does so too, with Cbz-Glu-Phe, but to a smaller extent. Using the ninhydrin method for estimation of the released tyrosine++ or phenylalanine previous elimination of amino acids++ and low-molecular peptides is necessary as it is too including alpha-amine nitrogen released by platelet proteases from peptides and proteins.

Animals↗
PubMed1987

[Progress in the analysis of amino acids with special reference to the determination of the intracellular amino acid pattern].

Intracellular amino acid patterns are nowadays considered as suitable criteria to evaluate the therapeutical effects of newly developed nutritional techniques. Owing to the low sensitivity and resolution of conventional amino acid analysis (ion exchange chromatography with ninhydrin-detection), reproducible and reliable studies to assess alterations in intracellular amino acid concentrations are, however, limited. In this study, for the first time a routinely manageable HPLC method allowing fully automated determination of free amino acids by employing on-line precolumn derivatization with ortho-phthaldialdehyde is presented. The highly sensitive fluorescence detection (less than 10 pMol/amino and injection) enables the measurement of intracellular/extracellular amino acid levels in various tissues (blood, muscle, liver, kidney, leukocytes) by using minimum amounts to sample material. Furthermore, the high resolution of the HPLC method facilitates the simultaneous determination of amino acid derivatives as well as short chain peptides. The error and the reproducibility of the method (expressed as the coefficient of variation) ranged between 1.0-4.7% and 0.4-2.2%, respectively. In addition to ortho-phthaldialdehyde, alternative precolumn-derivatization reagents are described and evaluated with special regard to their applicability in the routinely manageable determination of intracellular amino acids in biological material.

Amino Acids↗
PubMed1987

Paper-disc method for Campylobacter hippurate-hydrolysis test. A note.

Paper discs were impregnated with sodium hippurate dissolved in 1/15 phosphate buffer pH 7.2. The discs, each containing 2 mg substrate, were stored in dry state at room temperature. After adding a disc to bacteria suspended in distilled water, and incubated at 37 degrees C for 2 h, one drop of Skirrow and Benjamin's ninhydrin reagent was added and the reaction was read after re-incubation at 37 degrees C for 10 min. 169 campylobacter strains were tested. The results for a total of 169 strains were identical with those obtained with the modified rapid method of Skirrow and Benjamin. Of 92 campylobacter strains isolated from human faecal samples 59.8%, of 36 strains isolated from slaughtered poultry 41.7% proved to be Campylobacter jejuni.

Animals↗
PubMed1988

Homocysteine thiolactone in arteriosclerosis and cancer.

Homocysteine thiolactone was isolated from normal human plasma, sera of patients with acute myocardial infarction, and human neoplastic tissue. The compound was identified by ninhydrin reaction and by nitroprusside reaction following alkaline hydrolysis. Thin layer and ion exchange chromatography demonstrated a single uniform peak which co-chromatographed with authentic homocysteine thiolactone. The substance was isolated by extraction of plasma, serum or tissue with chloroform:methanol, re-extraction of the chloroform layer with dilue HCl, and evaporation of the resulting aqueous acid layer. The amount of homocysteine thiolactone was found to be 1,670 mumol/L in normal human serum and 12,500 mumol/L in sera of coronary heart disease patients. Although there is variability and overlap of values between groups, the difference between the two groups is significant (P = 0.025). The amount of homocysteine thiolactone in three human neoplasms was 17-123 mumol/kg. Only trace amounts were found in normal tissues, and none was detected in two other human neoplasms. The findings support the previous demonstration of abnormal homocysteine thiolactone metabolism in arteriosclerosis and cancer.

Adenocarcinoma↗
PubMed1988

A colorimetric procedure to monitor the extent of crosslinking of proteins by bisimidoesters.

Reaction of proteins with bisimidoesters is one of the popular crosslinking techniques. The extent of the reaction cannot be followed directly using the commonly used free amino group-determining reagents ninhydrin and 2,4,6-trinitrobenzene sulfonic acid since they react with bisimidoesters. However, we found that the extent of amidination of protein could be followed colorimetrically by using 1-fluoro-2,4-dinitrobenzene.

Animals↗
PubMed1987

Synthesis and hormonal activity of [Tyr22] glucagon and [desHis1, Tyr22] glucagon.

[Tyr22] glucagon and [desHis1, Tyr22] glucagon were synthesized by an improved solid phase procedure on a Pam-resin. The course of the synthesis was monitored by quantitative ninhydrin analysis and preview sequencing. Following cleavage by the low/high HF method the peptides were purified by ion exchange chromatography and reverse phase HPLC. The overall yield of homogeneous isolated peptide from the first amino acid was 41%. Circular dichroism measurements on dilute solutions in mixed aqueous organic solvents at pH 2, 6.9 and 9.2 showed increased beta-sheet structure relative to glucagon. [Tyr22] glucagon was a full agonist with 20-30% activity in the rabbit blood glucose assay and 10% activity in the rat liver membrane adenyl cyclase assay. [desHis1, Tyr22] glucagon had only a trace of activity in the adenyl cyclase assay (less than 0.002%) but bound to membranes in a competitive [125I] glucagon assay 1.0% as well as glucagon. The analog completely inhibited formation of cAMP by natural glucagon, with 50% inhibition at a ratio of 83:1 and pA2 = 6.7. The data are discussed in terms of models of glucagon structure in dilute solution.

Adenylyl Cyclases↗