[Properties of Euglena gracilis ribosomes and ribosomal RNA].
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Thiodiglycolic acid has been identified as a major metabolite of the anticancer drug ifosfamide in humans. Patients treated with 12-16 g ifosfamide/m2.day excreted thiodiglycolic acid ranging from 0.10 +/- 0.02 mmol on the first day of therapy, to a maximum of 3.27 +/- 0.15 mmol on the fourth day of ifosfamide infusion. This amounted to 5.4 +/- 0.2% of the administered dose of ifosfamide appearing as thiodiglycolic acid in urine during a 5 days' continuous ifosfamide infusion. Thiodiglycolic acid (50mg/kg) administered to rats inhibited the carnitine-dependent oxidation of [1-14C]palmitic acid by 55%, but affected neither the oxidation of [1-14C]octanoic acid, which is carnitine-independent, nor the oxidation of [1, 4-14C]succinic acid, a marker of Kreb's cycle activity. Additionally, thiodiglycolic acid (30 microM) inhibited oxidation of palmitic acid but not palmitoyl-L-carnitine in isolated rat liver mitochondria, indicating that it either sequesters carnitine or inhibits carnitine palmitoyltransferase I. This study elucidates a specific mitochondrial dysfunction induced by thiodiglycolic acid which may contribute to the adverse effects associated with ifosfamide chemotherapy.
The use of two novel similar indicator reactions as applied to the kinetic determination of Cu(II) in water is investigated. The methods rely on the catalytic effect of the analyte on the oxidation of thioglycolic (TGA) and thiolactic (TLA) acids by chromate in acidic media. The extent of the reactions was followed spectrophotometrically at 345 nm. Pseudo-first-order rate coefficients, k(obsd), were determined as a function of catalyst concentration. Interference of Fe(III) and Pb(II) was suppressed by complexation with pyrophosphate. For the reaction of TGA, a linear regression for k(obsd) versus [Cu(II)] was obtained for the entire concentration range considered. Although the plot corresponding to TLA oxidation exhibits a sharp change of slope at approximately 1.8x10(-5) M Cu(II), it can still be described effectively by two linear regressions with different slopes. The reaction of TGA is more sensitive than that of TLA at low Cu(II) concentration. The opposite is true for higher catalyst contents. The detection limits were 65 microg L(-1) for TGA and of 80 microg L(-1) for TLA oxidation, respectively. The relative standard deviations, of 0.4% for TGA and 1.1% for TLA oxidation, respectively, were obtained for five replicate runs at 1000 microg L(-1). Samples of river and wastewater from the mining region of Baia-Mare, Northern Romania were analyzed using the more sensitive reaction of thioglycolic acid. Results were compared to those obtained by the officially standardized methods. Good agreement was obtained, even for an untreated sample. Measurements did not require prior separation of interfering species.
Oxidation-reduction potential (Eh) levels were measured and standardized to pH (Eh7) for Trypticase soy broth containing various concentrations of reducing agents. Prereduced Trypticase soy broth with no added reducing agents exhibited a potential of -141 mV. Ascorbic acid at 0.2 to 0.005% and sodium thioglycolate at concentrations below 0.05% produced an Eh7 higher than the prereduced Trypticase soy broth containing no added reducing agents. The addition of cysteine hydrochloride,2-mercaptoethanol, and sodium formaldehyde sulfoxylate to prereduced Trypticase soy broth resulted in a reduction of Eh7 compared to the system without added reducing agents. The order of relative reducing intensity (from highest to lowest) for the reducing agents when comparing molar concentration was: sodium formaldehyde sulfoxylate,2-mercaptoethanol, cysteine hydrochloride, sodium thioglycolate, and ascorbic acid. Optimal growth of the test organism occurred at low Eh7 and low concentration of the reducing agents. A direct correlation existed between growth of the test organism and -Eh7 x -log concentration of the reducing agent.
New N2-cycloalkylidene-(6-phenyl/4-chlorophenylimidazo[2,1-b]thiazol-3-yl) acetic acid hydrazides (2a-h and 3a-b) were synthesized by reacting (6-phenyl/4-chlorophenylimidazo[2,1-b]thiazol-3-yl)acetic acid hydrazides with cyclohexanones or cyclopentanone. Furthermore, 2a-h were refluxed with thioglycolic or thiolactic acid to give 4-[[(6-phenyl/4-chlorophenylimidazo[2,1-b]thiazol-3-yl) acetyl]amino]-4-aza-1-thiaspiro[4.5]decan-3-ones (4a-h and 5a-h). The structures of the title compounds were established by spectral data (IR, 1H-NMR, 13C-NMR and EIMS (Electron Impact Mass Spectrometry)) and elemental analysis. The synthesized compounds were evaluated for antituberculosis activity against Mycobacterium tuberculosis H37Rv (ATCC 27294). The compounds exhibited varying degrees of inhibition in the in vitro primary screening that was conducted at a concentration of 6.25 micrograms/ml against M. tuberculosis H37Rv (ATCC 27294) in Bactec 12B medium using the Bactec 460 radiometric system or a broth microdilution assay, the Microplate Alamar Blue Assay (MABA). Compounds 2f, 2h, 3b, 4a, 4c, 4d, 5a-e and 5h demonstrating at 1-east 90% inhibition in the primary screen were re-tested at lower concentrations against M. tuberculosis H37Rv (ATCC 27294) to determine the actual minimum inhibitory concentration (MIC) using MABA. The most active compounds were found to be 4d and 5c. The structure-activity relationships of the derivatives were investigated.
Incorporation and oxidation of fatty acids (FA) were investigated in resident and thioglycolate-elicited (TG-elicited) rat macrophages (Mphi). Both cell types presented a time-dependent incorporation of [14C]-labeled palmitic acid (PA), oleic acid (OA), linoleic acid (LA), and arachidonic acid (AA) up to 6 h. The total amount of [14C]-FA incorporated by resident Mphi after 6 h was: AA > PA = LA > OA. TG-elicited cells presented a 50% reduction in the incorporation of LA, PA, and AA, whereas that of OA remained unchanged as compared to resident Mphi. The FA were oxidized by resident Mphi as follows: LA > OA > PA > AA. TG elicitation promoted a reduction of 42% in LA oxidation and a marked increase in AA oxidation (280%). The increased oxidation of AA in TG-elicited cells may account for the lower production of prostaglandins in Mphi under these conditions. The full significance of these findings for Mphi function, however, remains to be examined.
The stability of pathogenic bacteria from laboratory animals was investigated in various transport media at different temperatures. Bordetella bronchiseptica and Salmonella typhimurium survived for 8 days in phosphate-buffered saline (PBS, pH 7.0) at 37, 24, 4 and -20 degrees C; Brucella canis at 24, 4 and -20 degrees C; Corynebacterium kutscheri at 4 and -20 degrees C; and Pseudomonas aeruginosa at all but -20 degrees C. A marked decrease in numbers of Pasteurella multocida and Past. pneumotropica was observed in PBS at all temperatures. Skimmed milk in PBS improved the survival of Pasteurella spp. and Ps. aeruginosa at -20 degrees C. Neither glycerin, ascorbic acid nor sodium thioglycollate improved survival. The numbers of viable B. canis, Ps. aeruginosa and S. typhimurium were maintained in blood or faecal specimens held for 8 days at 4 degrees C. These results indicated that transport in PBS at 4 degrees C was the only method satisfactory for all species of pathogenic organisms tested, but Pasteurella spp. were the most difficult to maintain.
Trichloroacetic acid extracts of plasma were fractionated on a CG-50 resin column and the 50% acetic acid eluents chromatographed on silicic acid-impregnated glass paper in butanol-acetic acid-water. The specific arginine vasopressin (AVP) zone was eluted and assayed for antidiuretic activity in the diuretic rat. Thioglycolate inactivation was used to confirm AVP activity. Recovery of as little as 4 muU AVP per ml plasma ranged between 80 and 90%. In normal subjects after an overnight fast, plasma AVP ranged between 2.5 and 10.0 muU per ml. AVP secretion was inhibited by hemodilution and stimulated with nicotine and hypertonic saline. Plasma AVP was absent in patients with diabetes insipidus even after neurohypophyseal stimulation. Plasma AVP was abnormally elevated during mild dehydration and remained above the normal range despite hemodilution in patients with untreated adrenocortical insufficiency demonstrating a delayed water diuresis. Glucosteroid therapy lowered plasma AVP to normal in dehydrated patients. A normal diuretic response to hydration was accompanied by a fall in plasma AVP to zero in steroid-treated patients. These findings suggest that hypersecretion of AVP may play an important role in the abnormal water metabolism of adrenocortical insufficiency and that the glucosteroids promote normal water diuresis by inhibiting the secretion of AVP from the neurohypophysis.
Escherichia coli LSUFS was injured either by freezing at -10 degrees C or by heating at 57 degrees C for 12 min. Surviving cells were recovered on nonselective tryptone-glucose extract agar and selective violet red bile agar supplemented with compounds that degrade hydrogen peroxide or block its formation. Various concentrations of the following compounds were tested: sodium pyruvate, 3,3'-thiodipropionic acid, catalase, ascorbic acid, potassium permanganate, sodium thioglycolate, dimethylsulfoxide, ethoxyquin, n-propyl gallate, alpha-tocopherol sodium metabisulfite, and ferrous sulfate. Sodium pyruvate and 3,3'-thiodipropionic acid, when added to either medium, significantly (P greater than 0.01) increased recovery of injured cells. More than 90% of the heat-injured cells and 40 to 90% of the freeze-injured cells failed to grow on unsupplemented tryptone-glucose extract agar. Supplementation of violet red bile agar increased recovery, but the counts remained considerably lower than the tryptone-glucose extract agar counts. The repair detection procedure of Speck et al. (M. Speck, B. Ray, R. Read, Jr., Appl. Microbiol. 29:549-550, 1975) was greatly improved by the addition of pyruvate or 3,3'-thiodipropionic acid. However, when this improved repair detection procedure was applied to foods, pyruvate-supplemented media showed some false-positives. We therefore recommend that 3,3'-thiodipropionic acid be used to supplement media in the repair detection procedure.
Two acidic glycosphingolipids (gangliosides) derived from mouse macrophage membranes and separated by thin-layer chromatography have a strong cytostatic effect on human and mouse tumor cells. The structure of the two gangliosides, named M phi G1 and M phi G2, was elucidated by application of physicochemical and immunochemical methods. Gas chromatography and mass spectrometry of M phi G1 and M phi G2 classified them as isomeric monosialogangliosides with ceramide moieties composed of sphingosine as the long-chain base, C16 and C18 fatty acids, respectively, and a lacto-tetraose backbone. For M phi G1, additional immunochemical findings led to the proposed structure IV3NeuAc-nLcOse4Cer. The immunochemical reactions of M phi G2 suggest a branched structure for the oligosaccharide moiety.
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Peroxidase activity in neutrophils is higher than in thioglycollate macrophages, while in lymphocytes this enzyme activity is very low. Indole-3-acetic acid is oxidized by peroxidase and the role of this enzyme in the cytotoxic effect of the compound was evaluated by measuring oxygen consumption, light emission and cell death in neutrophils, macrophages and lymphocytes. The increase in light emission, oxygen consumption and rate of cell death in cells cultured in the presence of indole-3-acetic acid presented a direct correlation with the peroxidase activity of the cells as follows: neutrophils > thioglycollate macrophages > resident macrophages > lymphocytes. Indeed, in lymphocytes that possess very low peroxidase activity, indole-3-acetic acid did not result in an increase in light emission or oxygen consumption and it was not cytotoxic.
Tests were performed with 104 anaerobic microorganisms to evaluate the thioglycolate disk elution technique for the detection of resistance to cefoperazone and cefoperazone-sulbactam. An unacceptably high false-resistance rate and a poor reproducibility record make the disk elution procedure unsatisfactory for routine testing of this drug or combination of drugs.
Acid hydrolases, among them cathepsins A, B, C, and D, and their intracellular distribution have been studied in mouse peritoneal macrophages, a model commonly used for the study of mononuclear phagocyte functions in host-parasite relationships and in the immune response. Thioglycollate stimulated peritoneal macrophages showed high specific activities of acid hydrolases in compatison to liver and spleen. Fractionation of these macrophages by differential and isopycnic sucrose density centrifugation showed heterogeneous enyzme distribution patterns which were different for the various hydrolases studied. Thus, these enzymes appeared to be associated with particles of varying weight and density and in the different particles the ratios of the various acid hydrolase activities were quite dissimilar. With the majority of hydrolases a portion of the enzyme activity was found in fragile heavy particles of densities higher than 1.25 that sedimented together with the nuclei. Cultured macrophages derived from the non-irrated peritoneum exhibited a less heterogenous distribution pattern for acid phosphatase than did the thioglycollate stimulated cells. The heterogeneity of acid hydrolase distributions in the thioglycollate induced macrophages was attributed to their physiologic state of stimulated endocytosis causing a continuous formation of primary and secondary lysomes. Under certain conditions macrophages might contain lysosome-like particles with cathepsin ratios unfavorable for complete proteolysis. The existence of such particles is suggested as a possible explanation for the persistence of immunogenic protein within these cells.
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DNA superhelical tension, an important feature of genomic organization, is known to affect the interactions of intercalating molecules with DNA. However, the effect of torsional tension on nonintercalative DNA-binding chemicals has received less attention. We demonstrate here that the enediyne calicheamicin gamma1I, a strand-breaking agent specific to the minor groove, causes approximately 50% more damage in negatively supercoiled plasmid DNA than in DNA with positive superhelicity. Furthermore, we show that the decrease in damage in positively supercoiled DNA is controlled at the level of thiol activation of the drug. Our results suggest that supercoiling may affect both the activity of nonintercalating genotoxins in vivo and the accessibility of glutathione and other small physiologic molecules to DNA-bound chemicals or reactions occurring in the grooves of DNA.