SEARCH · PubMed Health

Results for “THIOSULFATES”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 829 records · Page 46Linked to original sources

PubMed1975

Tinea versicolor hypopigmentation: histochemical and therapeutic studies.

One hundred and thirty-four patients with tinea versicolor were divided into 3 treatment groups: (1) 30% sodium thiosulfate application, (2) 30% sodium thiosulfate application plus ultraviolet light, and (3) 30% sodium thiosulfate application, ultraviolet light, and meladinine tablets (amoidin 0.01 g and amidin 0.005 g). Analysis of the 79 patients who completed the 6-week study showed no statistical difference. Therefore, topical treatment should be instituted as quickly as possible to prevent pigmentary changes. Ultraviolet light should be used only after the fungus has cleared in order not to darken the skin further.

Adolescent↗

PubMed1998

In vivo effects of anti-inducers of the cysteine regulon in Salmonella typhimurium.

Growth on readily utilizable sulfur sources reduces expression of the cysteine regulon in Salmonella typhimurium. Inhibition of serine transacetylase by cysteine and direct actions of the anti-inducers sulfide and thiosulfate are responsible for reduction of expression. In order to evaluate individual contributions of each mechanism, the inhibitory effects of Na2S and Na2S2O3 were studied in strains with or without the capacity to synthesize cysteine from these compounds, using a transcriptional fusion to the cysDNC operon. In a cysK cysM strain, although cysteine synthesis from sulfide and thiosulfate was blocked, Na2S and Na2S2O3 efficiently reduced expression of the cysDNC operon. The inhibitory effect observed in this mutant was equivalent to 70-100% of that found in a strain carrying the fusion in a wild-type context grown in the same conditions. The actions of sulfide and thiosulfate as anti-inducers seem therefore to be responsible for most of the reduction of expression caused by these agents in vivo.

Bacterial Proteins↗

PubMed2001

Lithoautotrophic growth of the freshwater strain Beggiatoa D-402 and energy conservation in a homogeneous culture under microoxic conditions.

The freshwater filamentous bacterium Beggiatoa D-402 was shown to grow lithoautotrophically in a homogeneous culture under microoxic conditions only, the growth yield being the highest at 0.1 mg O(2) l(-1). High activities of the Calvin cycle key enzymes and of the dissimilatory path thiosulfate oxidation enzymes were found in the bacterial cells. The rate of CO(2) fixation above 112 nmol min(-1) (mg protein)(-1), an about 90% increase in the protein carbon at the expense of CO(2) carbon and an increase in the molar yield up to 12 mg dry weight (mmol oxidized thiosulfate)(-1) indicate the bacterial growth was autotrophic. Thiosulfate was oxidized by the strain almost completely into sulfate. The metabolically useful energy was conserved by oxidative phosphorylation that was coupled to oxidation of sulfur compounds. The bacterial membranes were found to contain CO-binding cytochromes b and two cytochromes c with M(r) 23 and 26 kDa, the terminal part of the respiratory chain containing presumably a cbb(3)-type oxidase. A cytochrome c with M(r) 12 kDa was detected in the soluble fraction.

Carbon Dioxide↗

PubMed1966

Cyanide intoxication: protection with oxygen.

Prophylactic protection against cyanide intoxication in mice can be enhanced by the administration of oxygen, especially when it is used in combination with the conventional cyanide antidotes, sodium nitrite and sodium thiosulfate. The LD(50) values were compared in groups of mice premedicated with sodium thiosulfate or sodium nitrite, or both, in air and in oxygen. These results indicate that oxygen alone provides only minimal protection. Although oxygen enhances the protective effect of sodium thiosulfate to a minor degree, it does not enhance the protection of sodium nitrite at all; and yet, it potentiates the effectiveness of a combination of these two antagonists against cyanide intoxication.

Animals↗

PubMed1986

Assimilatory reduction of sulfate and sulfite by methanogenic bacteria.

A variety of sulfur-containing compounds were investigated for use as medium reductants and sulfur sources for growth of four methanogenic bacteria. Sulfide (1 to 2 mM) served all methanogens investigated well. Methanococcus thermolithotrophicus and Methanobacterium thermoautotrophicum Marburg and delta H grew well with S0, SO3(2-), or thiosulfate as the sole sulfur source. Only Methanococcus thermolithotrophicus was able to grow with SO4(2-) as the sole sulfur source. 2-Mercaptoethanol at 20 mM was greatly inhibitory to growth of Methanococcus thermolithotrophicus on SO4(2-) or SO2(2-) and Methanobacterium thermoautotrophicum Marburg on SO3(2-) but not to growth of strain delta H on SO3(2-). Sulfite was metabolized during growth by Methanococcus thermolithotrophicus. Sulfide was produced in cultures of Methanococcus thermolithotrophicus growing on SO4(2-), SO3(2-), thiosulfate, and S0. Methanobacterium thermoautotrophicum Marburg was successfully grown in a 10-liter fermentor with S0, SO3(2-), or thiosulfate as the sole sulfur source.

Euryarchaeota↗

PubMed1997

Influence of sulfur oxyanions on reductive dehalogenation activities in Desulfomonile tiedjei.

The inhibition of aryl reductive dehalogenation reactions by sulfur oxyanions has been demonstrated in environmental samples, dehalogenating enrichments, and the sulfate-reducing bacterium Desulfomonile tiedjei; however, this phenomenon is not well understood. We examined the effects of sulfate, sulfite, and thiosulfate on reductive dehalogenation in the model microorganism D. tiedjei and found separate mechanisms of inhibition due to these oxyanions under growth versus nongrowth conditions. Dehalogenation activity was greatly reduced in extracts of cells grown in the presence of both 3-chlorobenzoate, the substrate or inducer for the aryl dehalogenation activity, and either sulfate, sulfite, or thiosulfate, indicating that sulfur oxyanions repress the requisite enzymes. In extracts of fully induced cells, thiosulfate and sulfite, but not sulfate, were potent inhibitors of aryl dehalogenation activity even in membrane fractions lacking the cytoplasmically located sulfur oxyanion reductase. These results suggest that under growth conditions, sulfur oxyanions serve as preferred electron acceptors and negatively influence dehalogenation activity in D. tiedjei by regulating the amount of active aryl dehalogenase in cells. Additionally, in vitro inhibition by sulfur oxyanions is due to the interaction of the reactive species with enzymes involved in dehalogenation and need not involve competition between two respiratory processes for reducing equivalents. Sulfur oxyanions also inhibited tetrachloroethylene dehalogenation by the same mechanisms, further indicating that chloroethylenes are fortuitously dehalogenated by the aryl dehalogenase. The commonly observed inhibition of reductive dehalogenation reactions under sulfate-reducing conditions may be due to similar regulation mechanisms in other dehalogenating microorganisms that contain multiple respiratory activities.

Anions↗

PubMed2002

An exported rhodanese-like protein is induced during growth of Acidithiobacillus ferrooxidans in metal sulfides and different sulfur compounds.

By proteomic analysis we found a 21-kDa protein (P21) from Acidithiobacillus ferrooxidans ATCC 19859 whose synthesis was greatly increased by growth of the bacteria in pyrite, thiosulfate, elemental sulfur, CuS, and ZnS and was almost completely repressed by growth in ferrous iron. After we determined the N-terminal amino acid sequence of P21, we used the available preliminary genomic sequence of A. ferrooxidans ATCC 23270 to isolate the DNA region containing the p21 gene. The nucleotide sequence of this DNA fragment contained a putative open reading frame (ORF) coding for a 23-kDa protein. This difference in size was due to the presence of a putative signal peptide in the ORF coding for P21. When p21 was cloned and overexpressed in Escherichia coli, the signal peptide was removed, resulting in a mature protein with a molecular mass of 21 kDa and a calculated isoelectric point of 9.18. P21 exhibited 27% identity and 42% similarity to the Deinococcus radiodurans thiosulfate-sulfur transferase (rhodanese; EC 2.8.1.1) and similar values in relation to other rhodaneses, conserving structural domains and an active site with a cysteine, both characteristic of this family of proteins. However, the purified recombinant P21 protein did not show rhodanese activity. Unlike cytoplasmic rhodaneses, P21 was located in the periphery of A. ferrooxidans cells, as determined by immunocytochemical analysis, and was regulated depending on the oxidizable substrate. The genomic context around gene p21 contained other ORFs corresponding to proteins such as thioredoxins and sulfate-thiosulfate binding proteins, clearly suggesting the involvement of P21 in inorganic sulfur metabolism in A. ferrooxidans.

Amino Acid Sequence↗

PubMed1970

Inhibitory action of tetrathionate enrichment broth.

Tetrathionate enrichment broth is a complex mixture of salts including iodides and other polythionates, but only thiosulfate (0.0736 m) and tetrathionate (0.0236 m) in combination were toxic for Escherichia coli. Individually, these two salts were not lethal. The lethal action of this thiosulfate-tetrathionate mixture affected only growing cells. A possible relationship between the lethality of the thiosulfate-tetrathionate mixture for a culture and its ability to reduce tetrathionate is suggested.

Bacteria↗

PubMed1980

Regulation of glucose transport and metabolism in Thiobacillus novellus.

To investigate the physiological basis of decreased rate of glucose utilization by Thiobacillus novellus in a mixotrophic environment (R. C. Perez and A. Matin, J. Bacteriol. 142:633-638, 1980), its glucose transport system was characterized and the modulation of this system as well as enzymes of glucose metabolism by the growth environment was examined. Uptake of 2-deoxy-d-glucose by cell suspensions was almost abolished by respiratory chain inhibitors, and the sugar accumulated unchanged inside the cells against a concentration gradient: its transport is probably linked to the proton electrochemical gradient. The glucose transport system, as well as several enzymes of glucose metabolism, had a high specific activity in heterotrophic cells, intermediate activity in mixotrophic cells, and low activity in autotrophic cells; thus, they are induced by glucose but repressed by thiosulfate, its metabolites, or both. Thiosulfate and sulfite inhibited the glucose transport system uncompetitively and noncompetitively, respectively (apparent K(i) = 3.1 x 10(-2) M and 3.3 x 10(-7) M, respectively) and also inhibited glucose-6-phosphate dehydrogenase activity. Thus, the rate of glucose utilization in mixotrophic environments decreased because thiosulfate and its metabolites repress as well as inhibit the glucose transport system and enzymes of glucose metabolism. The significance of this and other regulatory phenomena that come into play in such environments is discussed.

Biological Transport, Active↗

PubMed1981

Assimilatory sulfur metabolism in marine microorganisms: characteristics and regulation of sulfate transport in Pseudomonas halodurans and Alteromonas luteo-violaceus.

Sulfate transport capacity was not regulated by cysteine, methionine, or glutathione in Pseudomonas halodurans, but growth on sulfate or thiosulfate suppressed transport. Subsequent sulfur starvation of cultures grown on all sulfur sources except glutathione stimulated uptake. Only methionine failed to regulate sulfate transport in Alteromonas luteo-violaceus, and sulfur starvation of all cultures enhanced transport capacity. During sulfur starvation of sulfate-grown cultures of both bacteria, the increase in transport capacity was mirrored by a decrease in the low-molecular-weight organic sulfur pool. Little metabolism of endogenous inorganic sulfate occurred. Cysteine was probably the major regulatory compound in A. luteo-violaceus, but an intermediate in sulfate reduction, between sulfate and cysteine, controlled sulfate transport in P. halodurans. Kinetic characteristics of sulfate transport in the marine bacteria were similar to those of previously reported nonmarine systems in spite of significant regulatory differences. Sulfate and thiosulfate uptake in P. halodurans responded identically to inhibitors, were coordinately regulated by growth on various sulfur compounds and sulfur starvation, and were mutually competitive inhibitors of transport, suggesting that they were transported by the same mechanism. The affinity of P. halodurans for thiosulfate was much greater than for sulfate.

Bacteria↗

PubMed1967

Effect of oxygen on viability and substrate utilization in Chromatium.

Chromatium D can be exposed to oxygen for prolonged periods without any loss in motility or viability. Oxygen did not affect the rate of thiosulfate disappearance from the media, the oxidation of the inner sulfur atom of thiosulfate to sulfate, or the conversion of the outer sulfur atom of thiosulfate to intracellular sulfur, but it did inhibit the oxidation of intracellular sulfur to sulfate. Oxygen partially inhibited the uptake of pyruvate from the medium, but had little effect on the uptake of acetate. The distribution of label from pyruvate-2-(14)C into various cell fractions under aerobic conditions differed only slightly from that obtained under anaerobic conditions. Cells utilizing acetate-2-(14)C aerobically converted the majority of the metabolized acetate into a cell fraction with the solubility characteristics of poly-beta-hydroxybutyric acid, whereas under anaerobic conditions the acetate was distributed throughout the other cell fractions. Oxygen completely prevented the synthesis of bacteriochlorophyll.

Acetates↗

PubMed1979

Comparison of four plating media for isolating Vibrio cholerae.

Two brands of thiosulfate citrate bile salts sucrose agar and Monsur taurocholate tellurite gelatin (TTG) agar were compared with two newly developed media, sucrose tellurite teepol agar and Vibrio parahaemolyticus agar for isolation and identification of Vibrio cholerae. The thiosulfate citrate bile salts sucrose and TTG agars were the best selective media, whereas sucrose tellurite teepol agar was the poorest. Both TTG and sucrose tellurite teepol agars were good for use in follow-up serological tests, whereas only TTG agar could be used for follow-up oxidase tests. In our opinion TTG agar has more advantages for cholera research laboratories routinely culturing large numbers of patients for cholera on a daily basis and where media needs can be accurately predicted. In contrast, in smaller clinical laboratories or in laboratories investigating epidemics, thiosulfate citrate bile salts sucrose agar is best because it is commercially available and easy to prepare and can be used to distinguish colonies of suspect V. cholerae from V. parahaemolyticus.

Bangladesh↗

PubMed2006

Kinetics of Cisplatin and its monohydrated complex with sulfur-containing compounds designed for local otoprotective administration.

The anticancer drug cisplatin can cause permanent inner ear damage. We have determined the second-order degradation rate constant, k(Nu), of cisplatin and its more toxic monohydrated complex (MHC) in the presence of each of the sulfur-containing nucleophiles N-acetyl-l-cysteine, l-cysteine methyl ester, 1,3-dimethyl-2-thiourea, d-methionine, and thiosulfate, compounds that are under evaluation for local administration to prevent cisplatin-induced ototoxicity. MHC was isolated from a hydrolysis solution of cisplatin using liquid chromatography (LC). The degradations were evaluated by measuring the disappearance of MHC and cisplatin at 37 degrees C and pH 7.4 in the presence of each of the nucleophiles using LC and photometric detection. The k(Nu) of MHC and of cisplatin was 0.044 M(-1)sec(-1) and 0.012 M(-1)sec(-1) with N-acetyl-l-cysteine, 0.24 M(-1)sec(-1) and 0.067 M(-1)sec(-1) with l-cysteine methyl ester, 0.16 M(-1)sec(-1) and 0.074 M(-1)sec(-1) with 1,3-dimethyl-2-thiourea, 0.070 M(-1)sec(-1) and 0.069 M(-1)sec(-1) with d-methionine, and 3.9 M(-1)sec(-1) and 0.091 M(-1)sec(-1) with thiosulfate, respectively. Our results suggest that thiosulfate, as being the strongest nucleophile, is a promising candidate for local application in order to reduce the inner ear content of MHC and cisplatin. However, otoprotection is a multifactorial event, and it remains to be established how important nucleophilicity is for the effectiveness of the protecting agent.

Animals↗

PubMed1991

Intraperitoneal cisplatin-based chemotherapy for ovarian carcinoma.

Ovarian carcinoma demonstrates a steep dose-response curve for cisplatin, but even very small levels of acquired resistance at the cellular level are sufficient to block the efficacy of intravenous (IV) cisplatin. The intraperitoneal (IP) route of administration produces a 12-fold to 15-fold greater exposure for the peritoneal cavity, and concurrent use of IV thiosulfate permits the safe IP injection of 200 mg/m2 cisplatin. In this study, two phase II trials of an IP regimen containing cisplatin 200 mg/m2 and etoposide 350 mg/m2 with IV thiosulfate were conducted; the first trial enrolled patients with residual disease less than 2 cm who had failed primary cisplatin-based IV chemotherapy and the second trial newly diagnosed ovarian carcinoma patients irrespective of the size of residual disease after primary surgery. As salvage therapy, the IP cisplatin/etoposide regimen produced a median survival of 26 months from the start of IP therapy and 51 months from diagnosis. As first-line therapy, the median survival has not yet been reached; projected survival is 68% at 27 months. In both studies the major toxicity was myelosuppression; the use of concurrent thiosulfate almost completely eliminated serious nephrotoxicity and neurotoxicity. The size of the largest tumor mass was an important determinant of efficacy in both settings. The results of these trials are consistent with the hypothesis that increased drug delivery will result in higher response rates and improved survival. Data are sufficiently encouraging to mandate phase III randomized trials of this program.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1986

The enzyme rhodanese can be reactivated after denaturation in guanidinium chloride.

For the first time, the enzyme rhodanese has been refolded after denaturation in guanidinium chloride (GdmHCl). Renaturation was by either (a) direct dilution into the assay, (b) intermediate dilution into buffer, or (c) dialysis followed by concentration and centrifugation. Method (c) preferentially retained active enzyme whose specific activity was 1140 IU/mg, which fell to 898 IU/mg after 6 days. The specific activity of native enzyme is 710 IU/mg. Progress curves were linear for the dialyzed enzyme, and kinetic analysis showed it had the same Km for thiosulfate as the native enzyme, but apparently displayed a higher turnover number. Progress curves for denatured enzyme directly diluted into assay mix showed as many as three phases: a lag during which no product formed; a first order reactivation; and an apparently linear steady state. An induction period was determined by extrapolating the steady-state line to the time axis. The percent reactivation fell to 7% (t1/2 = 10 min) as the time increased between GdmHCl dilution and the start of the assay, independent of the presence of thiosulfate. The induction period, which decreased to zero as the incubation time increased, was retained in the presence of thiosulfate. There were no observable differences between native and renatured protein by electrophoresis or fluorescence spectroscopy. Previous reports of some refolding of urea-denatured rhodanese (Stellwagen, E. (1979) J. Mol. Biol. 135, 217-229) were confirmed, extended, and compared with results using GdmHCl. A working hypothesis is that rhodanese refolding involves intermediates that partition into active and inactive products. These intermediates may result from nucleation of the two rhodanese domains, which exposes hydrophobic surfaces that become the interdomain interface in the correctly folded protein.

Animals↗

PubMed1987

Isolation and characterization of a prokaryotic sulfurtransferase.

A sulfurtransferase has been purified to apparent homogeneity from the prokaryote Acinetobacter calcoaceticus lwoffi by conventional protein fractionation techniques. Steady-state kinetic studies of the enzyme revealed that its formal mechanism varies with the acceptor substrate employed. With inorganic thiosulfate as the sulfane sulfur-donor substrate and cyanide anion as the acceptor, the enzyme was shown to catalyze the reaction by a double displacement mechanism like that of mammalian rhodanese (thiosulfate:cyanide sulfurtransferase, EC 2.8.1.1). In contrast, with a thiol as the acceptor substrate at relatively high concentrations, the reaction proceeds by a single displacement mechanism, reminiscent of catalysis by another sulfur-transferase, thiosulfate reductase, glutathione-dependent (EC 2.8.1.3). When dithiothreitol is the acceptor substrate, the enzyme cycles through both the single and double displacement pathways, with the flux through each depending differentially on the concentration of dithiothreitol employed. In view of both the relaxed acceptor substrate specificity and the corresponding variability of formal mechanism, the more general name of sulfane sulfurtransferase is proposed for this bacterial enzyme.

Acinetobacter↗

PubMed1994

[Combined treatment of mechanical jaundice].

The causes of the development of hepatic insufficiency in patients with obstructive jaundice after nondosed surgical decompression of the biliary tract are analysed. The high efficacy of preoperative hemosorption in prevention of this complication was demonstrated in experiments on 120 animals. Similar results were obtained in the clinic in 60 patients. Five-day treatment with solutions of glucose, contrycal (gordox), and sodium thiosulfate improved the results of treatment of obstructive jaundice in 600 experimental jaundice, whereas aldactone, prednisolone, sodium oxybutyrate and methacine were poorly effective. In experiments with prolongation of the preoperative therapy to 8 days the mortality increased. Glucose, contrycal (gordox), sodium thiosulfate, sodium oxybutyrate, and aldactone given in the postoperative period increased the survival of the animals. It is suggested that the 4-5-day preoperative management of patients with obstructive jaundice should include contrycal (gordox), sodium thiosulfate, and hemosorption applied 24 hours before the operation. Aldactone and sodium oxybutyrate are recommended in addition after decompression of the biliary tract. Such treatment in 162 patients reduced postoperative mortality to 4.4% in comparison with the control group in which it was 16%.

Animals↗

PubMed1994

The sulfurtransferase activity and structure of rhodanese are affected by site-directed replacement of Arg-186 or Lys-249.

Two mutants of the enzyme rhodanese that replace Arg-186 with Leu (R186L) or Lys-249 with Ala (K249A) were prepared to test suggestions that these residues are involved in catalysis and structure. The predominant effect with R186L was functional, and Km for the sulfur donor, thiosulfate, increased from 3.7 mM to 73 mM with a modest decrease in Vmax (672 IU/mg to 576 IU/mg). However, K249A was virtually inactive using thiosulfate, but it was active with thiosulfonates such as p-toluene-, 2-aminoethane-, or ethanethiosulfonate, and these compounds could be demonstrated to form persulfide-substituted rhodanese. Compared with wild type enzyme, K249A had (a) reduced stability, (b) comparable secondary structure, (c) more easily exposed hydrophobic surfaces, and (d) a core structure that denatured similarly to the wild type enzyme. Thus, Arg-186 and Lys-249 are important in rhodanese catalysis, and Lys-249 is particularly critical for substrate selectivity and protein stability. Finally, the results suggest that there can be active rhodanese species in vivo that will be undetected using thiosulfate as a sulfur donor.

Amino Acid Sequence↗