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PubMed2001

[An IR study of ion solvation and association of lithium perchlorate in some organic solvents].

The infrared (IR) spectra of propylene carbonate (PC), gamma-butyrolactone (BL) and diethyl carbonate (DEC) in the presence of LiClO4 have been investigated. It is shown that the interactions between Li+ and these solvents occur on the oxygen atoms of the carbonyl of solvent molecules. On the other hand, spectral curve fitting for band shape of perchlorate anion shows the presence of ion association in these solutions.

4-Butyrolactone↗
PubMed2003

[Synthesis of ternary complexes of rare earth perchlorate with L-alanine and imidazale and the infrared spectral study].

The title complexes RE(Ala)4(Im)(ClO4)3.2H2O (RE = Sm, Pr or Nd) were synthesized by the reaction of rare earth perchlorates with alanine and imidazale in aqueous solution. The infrared spectra of the complexes were measured and their principal IR bands were assigned. The results show that alanine molecules are zwitterions in the complexes and coordinate with rare earth ions through carboxyl groups, and with the atomic weight of rare earth increasing, the ionization of the coordinate band decreases, while the convalence increases. Imidazale was found to coordinate with rare earth by nitrogen atom.

Alanine↗
PubMed1992

[Plasma endotoxin measured by the combination of new perchloric acid pretreatment method and endotoxin specific assay in liver cirrhosis].

Using with the newly modified perchloric acid pretreatment method and endotoxin specific assay (Endospecy), the plasma endotoxin in the patients with liver cirrhosis was investigated. The mean value of plasma endotoxin in control (n = 20) was below 9.8 pg/ml. The plasma endotoxin level in liver cirrhosis was 5.7 +/- 5.3 pg/ml (n = 70, mean +/- SD), and 20% of the patients (15 cases) showed above 9.8 pg/ml. Endotoxin level significantly correlated with the severity of liver function based on the Child-Turcotte classification (p less than 0.01). Plasma endotoxin positively correlated with total bilirubin (r = 0.417) and ICG clearance test (r = 0.298) and negatively correlated with prothrombin time (%) (r = 0.497) and HDL-cholesterol (r = 0.578) in the patients with liver cirrhosis. There was no correlation between esophageal varices and plasma endotoxin level. Plasma endotoxin was slightly detected in the patients with decompensated cirrhosis, and these data suggest that plasma endotoxin level in cirrhosis is not so elevated.

Bilirubin↗
PubMed2003

[Toxic effects of ammonium perchlorate on thyroid of rats].

OBJECTIVE: To study the effects of toxicity of ammonium perchlorate (AP) on thyroid of rats. METHODS: Eighty-eight Wistar rats were treated orally with different dosages of AP. Three treated groups received 129, 257, 514 mg.kg(-1).d(-1) of AP respectively and one control group drunk water for 13 weeks. Another 3 groups received 1.2, 46.5, 465.0 mg.kg(-1).d(-1) of AP respectively and one control group drunk water for 36 weeks. The behavior and change of body weight in rats were observed. The levels of thyroid hormones in serum were measured and the pathological changes of thyroid tissue were observed as well. RESULTS: There were no differences in behavior and change of body weight between different AP exposure time. When the rats were treated with AP 514 mg for 13 weeks, free triiodothyronine (FT3, 2.48 pmol/L), free thyroxin (FT4, 13.33 pmol/L) were lower than those in control group (3.24, 20.92 pmol/L respectively, P<0.05). Thyroid-stimulating hormone (TSH, 0.375 mIU/L), thyroglobulin (TG, 3.37 microg/L) were higher than those in control group (0.29 mIU/L, 2.00 microg/L respectively, P<0.05). When the rats were treated with AP 465 mg for 36 weeks, FT3 (2.65 pmol/L) was lower than that in control group (4.97 pmol/L, P<0.01). FT4 in 46.5, 465 mg groups (10.63, 2.17 pmol/L respectively) were lower than that in control group (15.74 pmol/L, P<0.05, P<0.01). TSH in 465 mg group (0.34 mIU/L) was higher than that in control group (0.14 mIU/L, P<0.05). Histopathologic examination showed that follicle proliferation, no colloid in follicle, gore, follicular diminishing or atresia were found in 46.5, 465 mg groups with a dose-effect relationship. CONCLUSIONS: The toxic effects of AP on the growth of rats were not found, but those on the thyroid of rats were found significantly. Thyroid is the target organ of AP. It is considered that none effect dose of AP for rat thyroid may be 1.2 mg.kg(-1).d(-1), its threshold dose may be 46.5 mg.kg(-1).d(-1).

Animals↗
PubMed2004

[Study on the injury effect of ammonium perchlorate to lung].

OBJECTIVE: To study the injury effect of ammonium perchlorate (AP) to lung and to explore whether AP can cause pulmonary fibrosis. METHODS: To detect the levels of cell counts, TNF-alpha, MDA, HYP and the synthesis of collagen in BALF or rat lung after a certain time when rats were injected AP by intratracheal instillation. RESULTS: AP could bring about acute lung damage and inflammatory reaction. The levels of TNF-alpha of different groups in different time were obviously higher than the normal control group(P < 0.05). AP could affect the levels of MDA, HYP and the synthesis of collagen. But it had no obviously pathological change of pulmonary fibrosis. CONCLUSION: There were acute injury effect about AP to lung, but this experiment could not make sure whether AP could cause pulmonary fibrosis.

Animals↗
PubMed2004

Thin-layer chromatographic behavior and separation of alkaline earth metals on silica gel in aqueous sodium perchlorate solution.

The thin-layer chromatographic behavior of alkaline earth metal ions (Mg2+, Ca2+, Sr2+, and Ba2+) in aqueous sodium perchlorate solutions on silica gel thin-layers impregnated with sodium hydroxide has been surveyed as a function of salt concentration. At salt concentrations above 2 mol 1(-1), the selectivity of the metals increased with a decrease in the crystal ionic radii; with further increases in salt concentration, the selectivity differences among the metals expanded remarkably. In the present systems, it was supposed that the cation exchange, the surface complexation, and the salting-out effect participate simultaneously in the adsorption of the metals on silica gel. Typical chromatograms for the mutual separation of the alkaline earth metals are presented.

Adsorption↗
PubMed2005

Transport of target anions, chromate (Cr (VI)), arsenate (As (V)), and perchlorate (ClO4-), through RO, NF, and UF membranes.

Rejection and transport of chromate (Cr (VI)), arsenate (As (V)), and perchlorate (ClO4-) by and through reverse osmosis, nanofiltration, and ultrafiltration were found to be affected by solution pH and ionic strength. In this study, the rejection of these target ionic contaminants increased with increasing pH at the same conductivity (ionic strength) for the tested membranes, regardless of salt type. General trends showed that the rejection followed the order: CaCl2 < KCl < or = K2SO4, at the same pH and conductivity condition. The rejection also significantly decreased as conductivity was increased regardless of the salt type. These results support the notion that a more negative surface charge due to increasing pH and/or decreasing ionic strength (conductivity) enhances rejection; lower molecular weight cut-off also enhances rejection. Measured values of hindered diffusion coefficient through the membrane pores (Dp) for the target contaminants significantly decreased as pH was increased, regardless of salt type at the same conductivity. At the same pH and conductivity, the Dp of the target contaminants follows the order: CaCl2 > KCl > K2SO4, in the presence of different types of salts. The Dp of the target contaminants significantly increased as conductivity was increased regardless of the salt type. The rejection data were modeled by application of a non-equilibrium thermodynamic model. The rejection model has five transport parameters: the molecular transport coefficient (omega), osmotic pressure gradient (deltaII), molecular reflection coefficient (sigma), the average bulk fluid interfacial concentration between the feed and permeate side (C(avg)), and the solvent flux (Jv). The transport parameters were determined by independent measurements (and calculation with minimum assumptions.) Measurements and predictions of the target contaminant transport were in good agreement.

Arsenates↗
PubMed1991

[Study of human muscle biopsies with muscle glycogen storage diseases using 1H nuclear magnetic resonance spectroscopy (NMRS)--analysis of perchloric acid extracts of muscles].

Muscle metabolites of perchloric acid extracts in human muscle biopsies including the cases with muscle glycogen storage diseases (GSD) were analyzed using 1H NMR spectroscopy. Several metabolites such as lactate, pyruvate, creatine, phosphocreatine, acetate, alanine, carnitine and glycogen were recognized. The cases with GSD III and GSD V showed two broad signals at 3.60 and 3.85 ppm which were considered to be the proton signals from the accumulated glycogen. However, in GSD III, the signal at 3.60 ppm was high compared with that at 3.85 ppm suggesting that glycogen was increased in its degree of branching joined by alpha-1,6 linkage. These data suggest that 1H NMR spectroscopy is a useful and simple technique for analysis of muscle glycogen storage diseases as well as lipid myopathies.

Adult↗
PubMed1975

Perchloric acid-soluble proteins and protein-bound hexoses in serum and tissues of normal, hypo-and hyperthyroid rats.

The total content of perchloric acid-soluble proteins (PCA-SP) and protein-bound hexoses (PBH) were studied in blood serum and tissues (liver, kidney, lung, brain) of normal, hypo- and hyperthyroid rats. The results obtained indicate that the hyperthyroid state induced an increase in both PCA-SP and PBH in blood serum and studied tissue homogenates, and hypothyreosis causes a decrease of total glycoproteins content in all studied materials. The results were counted per 1 g of protein and in this way the nonspecific effect of thyroid hormones on the protein metabolism had no influence on the measurements.

Animals↗
PubMed1978

Buffer-exchange column for rapid separation of carcinoembryonic antigen from perchloric acid.

A Sephadex G-50 medium (Pharmacia) buffer-exchange column has been developed for rapidly changing the medium for carcinoembryonic antigen from perchloric acid to acetate buffer. Analytical recovery of the extracted antigen exceeded 95%. Plasma for analysis can be so prepared and samples ready for analysis within an hour. The technique also results in uniform assay volume, thus eliminating this variable from the assay.

Buffers↗
PubMedDate not supplied

Perchloric acid, toxicolor, endospecy, and miconazole in the early diagnosis and treatment of fungemia.

As a procedure for the diagnosis of fungemia, Toxicolor and Endospecy (limulus tests using a synthetic chromogenic substrate) were used to measure (1----3)-beta-D-glucan (beta-glucan), which is a membranous component of fungus. The plasma samples were pretreated with a new perchloric acid method. These methods permit measurement of the beta-glucan within about two hours. Patients in whom fungemia was diagnosed were effectively treated with miconazole.

Adult↗
PubMed1990

Inhibition of lactate dehydrogenase isoenzymes by sodium perchlorate evaluated.

We evaluated a method of measuring lactate dehydrogenase isoenzyme 1 (LD-1) selectively (Clin Chem 1987;33:991-2), in which all other LD isoenzymes were inhibited by adding sodium perchlorate to the reaction medium to a final concentration of 0.825 mol/L. In this study we used the different isoenzymes purified from human autopsy tissue and found that the originally published amount of inhibitor (a) increased the original LD-1 activity and (b) did not eliminate all enzyme activity of LD-2 and LD-3. Interference by LD-2 was further demonstrated. Thus we conclude that this method cannot be used for the selective determination of LD-1 because its results do not accurately reflect the original LD-1 activity.

Humans↗
PubMed1989

[Transitory efficacy of potassium perchlorate in hypothyroidism caused by amiodarone].

We report a case of a patient with hypothyroidism due to amiodarone. The short-term administration (1 g/die for 10 days) of potassium perchlorate (KClO4) led to normalization of serum thyroid hormone concentrations and marked reduction of thyrotropic hormone. The reduction of KClO4 (400 mg/die) and its following withdrawal led to reappearance of hypothyroidism signs. No side-effects or toxic reactions occurred during KClO4 therapy. This anion competitively inhibits thyroid iodide transport, reducing intrathyroidal iodide content and removing thyroid hormone synthesis inhibition. We suggest KClO4 therapy when amiodarone-associated hypothyroidism impairs a pre-existent cardiac disease and when a quick restoration of euthyroidism is necessary. Nevertheless, we emphasize that its effect can be transitory in cases of short-term treatment or low doses.

Aged↗
PubMed1987

Potassium perchlorate, potassium iodide, and propylthiouracil: promoting effect on the development of thyroid tumors in rats treated with N-bis(2-hydroxypropyl)-nitrosamine.

The effect of 1000 ppm potassium perchlorate (KClO4), 1000 ppm potassium iodide (KI) or 1000 ppm propylthiouracil (PTU) in the diet on the development of thyroid tumors was studied histologically and biochemically in Wistar rats given a single ip injection of 280 mg of N-bis(2-hydroxypropyl)nitrosamine (DHPN) per 100 g body weight. Basal diet containing 100 ppm KClO4, 1000 ppm KI or 1000 ppm PTU was given for 19 weeks from week 2 to week 20. The incidence of thyroid adenomas at the end of week 20 of the experiment was 100% (20/20) in rats treated with DHPN followed by KClO4, 85% (17/20) in rats given DHPN followed by KI, 95% (19/20) in rats given DHPN followed by PTU, and 5% (1/20) in rats given DHPN alone. The incidence of thyroid cancers was 100% (20/20) in rats treated with DHPN followed by KClO4, 65% (13/20) in rats treated with DHPN followed by KI and 0% (0/20) in rats treated with DHPN followed by or not followed by PTU. Rats given KClO4, KI or PTU alone and untreated rats had no thyroid tumors. The mean values of TSH in serum were 2.94 +/- 0.79 ng/ml in rats treated with DHPN followed by KClO4, 9.40 +/- 16.0 ng/ml in rats treated with DHPN followed by KI and 60.94 +/- 20.60 ng/ml in rats treated with DHPN followed by PTU. It was confirmed that (1) KClO4, PTU and KI promote the development of thyroid tumor in rats treated with DHPN, (2) the promoting effect of KClO4 or KI is stronger than that of PTU and (3) the value of TSH in serum is not parallel to the promoting effect on the development of thyroid tumor.

Animals↗
PubMed1988

Reduced acid protease activity in vitro of lysosomes from thyroid gland of rats chronically treated with propylthiouracil and perchlorate.

We have recently demonstrated that proteolytic activity of lysosomal acid proteases from papillary carcinoma is significantly higher than in morphologically normal thyroid tissue. In the present study the activity of lysosomal acid proteases from parenchymatous proliferated thyroid epithelium, induced by action of antithyroid substances, has been examined in an in vitro system using 125I-labelled rat thyroglobulin as a substrate. Thyroid lysosomes were isolated from rats treated chronically for 3-4 weeks with propylthiouracil (PTU, 0.1% in drinking water) and perchlorate (NaClO4, 200 mg/rat/day) by centrifugation between 800 and 20,000 x g. It was observed that, in contrast to human malignant thyroid tissue, the proteolytic activity of lysosomal acid proteases from antithyroid substance-induced hyperplastic goitre was markedly reduced in comparison with control thyroid tissue (29-50%). Since reduced activity of total lysosomal proteases was found both per unit of wet weight thyroid tissue and per unit of lysosomal proteins, the results suggest that changes in lysosomal enzymes may probably have more quantitative than qualitative nature.

Animals↗
PubMed1988

The effect of perchloric acid fixation on DNA preservation in the salivary gland of Bradysia hygida.

In Bradysia hygida (Diptera, Sciaridae) well spread polytene chromosomes, free of cytoplasm, and with good morphology are consistently obtained if before squashing in acetic acid solution, the salivary glands are fixed in 7% perchloric acid containing small amounts of ferric ions (SAUAIA et al. 1971). We show here that, with regard to the preservation of total incorporated 3H-thymidine and with regard to the relative autoradiographic labelling of expanded chromosome regions as compared to the labelling of a non-expanded one, this method is equivalent to fixing the salivary glands in ethanol-acetic (3:1). We show also that if this kind of preparation is subject to mild acid hydrolysis a small amount of the total 3H-labelled material may be lost.

Animals↗
PubMed1984

Addition of perchloric acid to blood samples for colorimetric limulus test using chromogenic substrate: comparison with conventional procedures and clinical applications.

Preexposure of blood samples to perchloric acid permitted an accurate, quantitative measurement of endotoxin levels as low as 1 pg/ml using a colorimetric limulus test. Conventional chloroform and dilution-heating methods were unsatisfactory because of high residual nonspecific amidolytic activity and poor recovery. The normal peripheral plasma endotoxin level was less than 10 pg/ml when Escherichia coli 0111:B4 endotoxin was used as a reference. One nanogram in this assay was equivalent to 2.9 endotoxin units of USP reference standard endotoxin (E. coli 0113). High values were noted in portal venous blood and in cases of acute hepatitis, liver cirrhosis, strangulation ileus, pyothorax, lung abscess, diffuse panbronchiolitis, and pneumonia. Normal human plasma and serum exhibited a high capacity to inactivate added endotoxin. E. coli 0111:B4 and Salmonella minnesota 9700 were more susceptible to inactivation than Pseudomonas aeruginosa endotoxin. This inactivating activity was temperature dependent, was maximal between 37 degrees and 45 degrees C, and disappeared completely after heating plasma or serum to 56 degrees C for 30 minutes prior to the addition of endotoxin. The E. coli 0111:B4 endotoxin-inactivating activity of normal platelet-rich plasma, platelet-poor plasma, and serum, all at 37 degrees C, was 8.1 +/- 3.1, 11.7 +/- 4.5, and 15.2 +/- 4.9 micrograms/min/ml (mean +/- SD; n = 4), respectively. Endotoxin-inactivating activity was markedly decreased in plasma from patients with endotoxemia, but returned to normal with recovery from the underlying illness.

Colorimetry↗