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PubMedDate not supplied

Physiological activity of some aminophosphonates.

Influence of some new aminophosphonates on electrolyte leakage from cucumber (Cucumis sativus cv "Wisconsin") cotyledons as well as on the content of chlorophyll and activity of guaiacol and pyrogallol peroxidase were studied. Concentration of malondialdehyde (MDA), one of the end-products of lipid peroxidation, was also measured. It was found that aminophosphates influenced the parameters observed to various extents, depending on their structural features and the concentration used. Most active modifiers were those possessing sufficiently long hydrocarbon substituents at the nitrogen atom and/ or iso-propyl chain at the phosphorus atom.

Amines↗
PubMed1996

Protein losses in continuous renal replacement therapies.

Continuous renal replacement therapy (CRRT) has become a popular treatment modality but may have the disadvantage of producing substantial protein losses. With use of the Biuret method, a relatively insensitive assay, dialysate/ultrafiltrate protein losses have been reported to be as high as 1.3 g/L. With CRRT outputs of up to 50 L/day, these values would amount to protein losses of up to 65 g/day. In this study, dialysate/ultrafiltrate protein losses were reanalyzed by using a highly sensitive microprotein reagent (pyrogallol red) considered to be more accurate than previously available methods. Twenty-two dialysate/ultrafiltrate samples were obtained from Amicon-20 Diafilters or Fresenius F-80 dialyzers during continuous venovenous hemofiltration (CVVH) or continuous venovenous hemodialysis/hemodiafiltration (CVVHD/F). Mean hourly output for all treatments was 1637 +/- 694 mL/h. Mean protein concentration for all 22 dialysate/ultrafiltrate samples was 4.2 +/- 4.0 mg/dL. Mean dialysate/ultrafiltrate protein concentrations were similar for the Amicon 20 (3.4 +/- 4.4 mg/dL, N = 9) and the Fresenius F-80 (4.7 +/- 3.9 mg/dL, N = 13) (P = not significant). Protein losses were higher during convection-based CVVH (6.0 +/- 5.1 mg/dL, N = 10; range, 1 to 15 mg/dL) than during the mixed convection and diffusion-based CVVHD/F (2.7 +/- 1.9 mg/dL, N = 12; range, 0 to 6 mg/dL) (P = 0.049). Mean serum protein concentration at the time of dialysate/ultrafiltrate sampling was 4.7 +/- 1.8 g/dL. There was a weak, but statistically significant correlation between the dialysate/ultrafiltrate samples and the corresponding value for serum protein (r = 0.468, P < 0.03). It was concluded that protein losses during CRRT treatments are substantially lower than previously reported, are dependent on the serum protein concentration and the predominant nature of solute removal (convection versus diffusion), and can vary between 1.2 and 7.5 g/day.

Blood Proteins↗
PubMed2000

Inhibitory actions of hydroxocobalamin, cyanocobalamin, and folic acid on the ultraviolet light-induced relaxation of the frog upper oesophageal strip.

The applications of ultraviolet (UV) light (336 nm) on the upper oesophageal strips of frog elicited relaxant responses in the presence of NaNO2 (50 microM). The tissues were mounted under the tension 0.5 g in an organ bath containing Ringer solution, maintained at 25 degrees C and gassed with 100% O2. The responses were recorded on a kymograph via an isotonic lever. Antimegaloblastic agents, including hydroxocobalamin (1, 10, and 100 microM), cyanocobalamin (1, 10, 25, and 100 microM), and folic acid (1, 10, 50, 100, and 200 microM), significantly attenuated the relaxation response to UV light. Folinic acid (1, 10, 25, and 100 microM), however, enhanced the relaxation. Pyrogallol (50 microM), hydroquinone (50 microM), and diethyldithiocarbamic acid (8 mM) were found ineffective for attenuation, though FeSO4 (200, 400, and 500 microM) and hemoglobin (50 microM), respectively, exerted significant inhibition. L-arginine methylester (500 microM) did not impair UV-induced relaxation. Based on these results, we concluded that a mechanism involving undefined action(s) of antimegaloblastic drugs may cause alterations in the UV light-induced relaxation of the tissue used.

Animals↗
PubMed2001

Measurement of dissolved oxygen based on enhanced cerium(IV) chemiluminescence.

The reaction of Ce(IV) with pyrogallol caused chemiluminescence, which was enhanced by dissolved oxygen. Dissolved oxygen in water was able to help in the determination by enhancing the chemiluminescence intensity. The limit of detection calculated from 3sigma was 43 micromol/dm3, and the relative standard deviation was 1.2% at 613 micromol/dm3 (n = 5). The results obtained for natural and tap water samples were compared with those provided by conventional methods; the agreement between them corroborated the usefulness of the proposed method. The chemiluminescence mechanism was studied by examining the effect of interference with Cl- and measuring the chemiluminescence spectrum. The chemiluminescence emitter, however, could not be identified.

Calibration↗
PubMed2005

Spectrophotometric determination of urinary protein with o-sulfophenylfluorone-metal complex.

A simple and sensitive spectrophotometric method for the determination of human serum albumin (HSA) was established based on the ternary complex-formation reaction of HSA with o-sulfophenylfluorone (SPF) as a xanthene dye and metal ion (niobium(V) and bismuth(III)) in the presence of a dispersion agent. This new method enabled the determination of HSA in the range of 1 - 15 microg/ml HSA by measuring the difference of the absorbance at 530 nm between HSA-SPF-metal ion and SPF-metal ion solutions. In the determination of HSA, this method is about 2-times more sensitive than the Pyrogallol Red-molybdenum(VI) method (PR method), which accounts for more than 80% of the quantification methods for urinary protein assays in Japan. There was no significant difference between the results obtained by the present method and the PR method for human urine samples. The binding process between the SPF-metal complex and HSA was studied by determining the binding parameters and the thermodynamic parameters.

Albuminuria↗
PubMed2005

Effects of antioxidant vitamins on glutathione depletion and lipid peroxidation induced by restraint stress in the rat liver.

BACKGROUND AND AIM: Stress as a cofactor has been reported to affect the progression and severity of several diseases. The influence of stress on the liver is of interest from the clinical point of view because stress plays a potential role in aggravating liver diseases in general and hepatic inflammation in particular, probably through generation of reactive oxygen species. The present study was undertaken to investigate the potential of the antioxidant vitamins A (retinol), E (tocopherol) and C (ascorbic acid) individually and in combination (vitamin E + C) to modulate restraint stress-induced oxidative changes. These effects were determined by measuring changes in hepatic levels of free radical scavenging enzymes such as superoxide dismutase (SOD), glutathione-S-transferase (GST) and catalase, as well as levels of total glutathione (GSH), malondialdehyde (MDA), aspartate aminotransferase (AST) and alanine aminotransferase (ALT). METHODS: Immobilisation was achieved by placing the animals in wire mesh cages of their size. The rats were orally administered vitamins A, E and C individually and in combination (E + C) prior to and after 6 hours of immobilisation stress exposure. The hepatic levels of SOD, GST, catalase, GSH and MDA were determined by spectrophotometric methods. Liver SOD activity was assayed by monitoring the amount of enzyme required to inhibit autoxidation of pyrogallol by 50%. Hepatic GST was monitored by following the increase in absorbance at 340 nm of CDNB-GSH conjugate generated due to GST catalysis between GSH and CDNB. Catalase activity in liver tissues was determined using peroxidase as the substrate. Lipid peroxidation was measured by determining the level of thiobarbituric acid reactive substances. ALT and AST were determined by commercial kits. RESULTS: Six hours of immobilisation stress caused a decrease in liver levels of SOD (p = 0.001), catalase (p = 0.031), GST (p = 0.021) and GSH (0.013), while levels of MDA (p = 0.0015), AST (p = 0.05) and ALT (p = 0.046) were increased compared with non-stressed control rats. Both pre-vitamin stress and post-vitamin stress treatments either alone or in combination were associated with increased normalisation of these parameters towards control values, with post-vitamin treatment being the more effective of the two. Vitamins E and C individually were found to be more effective in restoring the endogenous antioxidant system than vitamin A. The combined vitamin (E + C) post-stress treatment was found to be effective but not additive in combating hepatic oxidative stress. The beneficial effects of these vitamin treatments were also reflected in reversions of altered AST and ALT levels towards their control values. CONCLUSION: Vitamins E or C alone or in combination can be given as prophylactic/therapeutic supplements for combating scavenging free radicals generated in liver tissue. This approach may reduce oxidative stress caused by diseases such as cirrhosis.

Animals↗
PubMed1995

Nutritional toxicology of tannins and related polyphenols in forage legumes.

Proanthocyanidins (PA) (condensed tannins) and hydrolyzable tannins (HT) are the two major classes of tannins. Proanthocyanidins are flavonoid polymers. Hydrolyzable tannins are polymers of gallic or ellagic acid esterified to a core molecule, commonly glucose or a polyphenol such as catechin. Proanthocyanidins are the most common type of tannin found in forage legumes. Problems in the analysis of tannins are that sample processing and drying decrease extraction and reactivity, suitable standards are unavailable, and quantitative analytical methods are poorly correlated with enzyme inhibition, protein precipitation, and nutritional effects. Hydrolyzable tannins are potentially toxic to ruminants. Pyrogallol, a hepatotoxin and nephrotoxin, is a product of HT degradation by ruminal microbes. Proanthocyanidins are considered to be non-toxic because they are not absorbed, but they are associated with lesions of the gut mucosa. Research on tannins in forage legumes has determined their effects on protein digestion and metabolism but more research on tannin structure in relation to digestion of specific proteins is needed. The widely accepted explanation for positive effects of PA on protein digestion and metabolism is that PA-protein complexes escape ruminal degradation and the protein is available in the lower tract. This proposed mechanism may be incorrect because PA also complex carbohydrates, endogenous proteins, and microbial products and the degradability of PA-protein complexes by ruminal microbes has not been adequately studied. Several alternative hypotheses (to escape protein) that explain the effect of PA on protein digestion and metabolism in ruminants are also consistent with experimental results on forage legumes. These include increased microbial protein synthesis, increased use of endogenous nitrogen in the rumen, and increased secretion of salivary glycoproteins. Research on manipulating the content and type of PA in forage legumes is justified because they are associated with non-bloating legumes, lower soluble non-protein nitrogen in silage, and improved efficiency of protein utilization. Research on the biosynthesis, molecular genetics, and cell biology of PA in forage legumes needs to be integrated with research on toxicology and nutrition.

Animal Feed↗
PubMed1996

The copper complex of captopril is not a superoxide dismutase mimic. Artefacts in DMPO spin trapping.

The effect of captopril and of its copper complex on several superoxide-dependent reactions used to detect and assay superoxide dismutase activity was studied, including pyrogallol and hematoxylin autoxidation and Nitro Blue Tetrazolium reduction. In none of these systems were superoxide dismutase-like properties of captopril/Cu apparent. Captopril/Cu decreased the yield of DMPO-OH adducts generated by KO2 but this effect may be due to the acceleration of the decay of the adduct by captopril/Cu.

Antioxidants↗
PubMed1999

Inhibition of gastric H+, K(+)-ATPase by flavonoids: a structure-activity study.

Gastric H+, K(+)-ATPase plays a pivotal role in the final step of gastric acid secretion. Over 80 flavonoids, including flavones, flavanones, isoflavones and anthocyanidins were examined for their in vitro effect on gastric H+, K(+)-ATPase and some were found to be inhibitors of this enzyme. Kinetic studies showed that the inhibition of H+, K(+)-ATPase by flavonoids was competitive with respect to ATP, and non-competitive with respect to K+. Structure-activity analysis revealed the following: (1) The inhibitory potency of flavonoids depends on the number of hydroxyl groups up to four per molecule and that above this, no marked enhancement is seen; (2) The hydroxylation pattern is an important determinant of inhibitory potency. Two adjacent hydroxyl groups (catechol-type), three adjacent hydroxyl groups (pyrogallol-type) or hydroxyl groups at C-3, C-5 and C-7 are a minimum requirement for high potency inhibition; (3) Protection of the hydroxyl group(s) by glycosylation or methylation decreases potency; (4) Saturation of the C-2-C-3 double bond results in a decrease in potency; and (5) A ketone at C-4 is not essential for inhibition.

Animals↗
PubMed1996

The effects of SS-cream and its individual components on rabbit corpus cavernosal muscles.

SS-cream (Severance Secret cream) is made up of extracts from 9 natural products for treating premature ejaculation (PE). SS-cream has been proved to be effective in the treatment of PE in pilot clinical studies. It has also been found to have a potentiating effect of their erectile capacity in some patients. Therefore, we investigated the pharmacological actions of SS-cream and the extracts of its individual components in rabbit corpus cavernosal smooth muscle to realize the effect of SS-cream on penile erection. Extracts of Bufonis Venenum induced a dose-related contraction of rabbit corpus cavernosal muscle, which was significantly inhibited by phentolamine. Extracts of Caryophylli Flos induced a dose-related relaxation in the muscle strips precontracted with phenylephrine (5 x 10(-6)M; PHE). Caryophylli Flos caused a dose-dependent inhibition of the PHE induced contraction and also inhibited the contractility of Bufonis Venenum. Other extracts, when used individually or in a mixture, induced a dose-related relaxation in the precontracted muscle strips with PHE. SS-cream began to exert a relaxing effect at the concentration of 0.05 mg/ml in the muscle strips precontracted muscle strips with PHE (5 x 10(-6)M); causing dose-dependent relaxation with a maximal effect at 0.2 mg/ml. The relaxation effect of SS-cream was partially inhibited by endothelial disruption and by pretreatment with methylene blue, pyrogallol, atropine, and indomethacin, although they were not statistically significant. The results show that SS-cream has a relaxing effect on cavernosal smooth muscle. And it is partly related with enhancing the NO/cyclic GMP pathway although the relaxation mechanism in detail remains to be elucidated. Therefore, SS-cream may be effective for future treatment of mild erectile dysfunction, in addition to its role for premature ejaculation.

Animals↗
PubMed1997

Effect of sodium glycyrrhetinate on chemical peritonitis in rats.

AIM: To study the anti-inflammatory mechanisms of sodium glycyrrhetinate (SG). METHODS: Rat chemical peritonitis was used. The protein content and prostaglandin E2 (PGE2) content in exudate were measured by Folin-phenol assay and RIA, respectively. SOD activity in neutrophils (Neu) was determined by pyrogallol-NBT colorimetry. cAMP content in Neu was detected by competitive protein binding assay. RESULTS: In peritonitis caused by histamine, SG 10-20 mg.kg-1 i.m. reduced exudate volume and Neu counts, and 5-20 mg.kg-1 i.m. lowered the protein content in exudate. In peritonitis induced by carrageenan, SG 20 mg.kg-1 i.m. reduced exudate volume, Neu counts, protein content and PGE2 content in exudate, increased SOD activity in Neu, but did not affect beta-glucuronidase release from Neu. In peritonitis induced by arachidonic acid, SG 20 mg.kg-1 i.m. reduced Neu counts, protein content, and PGE2 content in exudate, and attenuated the reduction of cAMP level in Neu. CONCLUSION: SG exerts its anti-inflammatory action by lowering permeability of capillaries in inflammatory site, inhibiting Neu emigration and PGE2 biosynthesis, and scavenging oxygen free radicals.

Animals↗
PubMed1997

[Circadian variations of plasma SOD and MDA in health subjects].

Oxygen derived free radical system has been to be implicated in the pathogenesis of many diseases, such as cardiovascular disease, tumor, trauma and radiation injury. Many studies have suggested that oxygen free radical initiate a series of events that result in cell membrane alterations leading to the development of cell injury. The objective of the present study was to examine the circadian characteristics of some parameters of this system in the blood. One parameter was superoxide dismutase (SOD), a major oxygen free radical scavenger; the other was malondialdehyde (MDA), an important product of lipid peroxidation initiated by oxygen free radicals. Blood samples were collected at 6 h intervals beginning at 08:00 over a 24 h span in nine healthy volunteers (5 females, 4 males, average age 30 +/- 5 years). All participants were synchronized for one week with diurnal activity from 07:00 to 23:00 and nocturnal rest, with three meals served at 07:30, 12:00 and 19:00. Plasma SOD, MDA levels were measured by pyrogallol autoxidation assay, thiobarbituric acid spectrophotometry respectively, and the data were fitted with a 24 h cosine curve and analyzed further by a population-mean cosinor. The results showed that the plasma SOD levels exhibited a highly significant circadian rhythm (P < 0.001) in healthy subjects, with acrophase (phi) at 21:17, mesor (M) of 3975.3 +/- 680.5 u/g Hb, and amplitude (A) of 273.62 u/g Hb. A circadian rhythm of plasma MDA was also detected (P < 0.01), phi = 15:15, M = 4.23 +/- 0.86 mumol/L, A = 2.37 mumol/L). The evaluation of circadian natures of SOD and MDA may be important in the prevention, diagnosis and treatment of associated diseases.

Circadian Rhythm↗
PubMed1975

Presence of carotenoids in the erythrocyte membranes of carotenemic and noncarotenemic individuals.

Erythrocytes and erythrocyte membranes obtained from carotenemic (serum carotene greater than 4.0 mg/liter) and noncarotenemic individuals contain a small amount of carotenoid pigments. The principal pigment isolated from erythrocytes and erythrocyte membranes from carotenemic individuals cochromatographed with, and has an absorption spectrum similar to, authentic beta-carotene. Traces of beta-carotene were also found in the extracts of the erythrocytes and membranes obtained from the noncarotenemic individuals. These pigments were demonstrable only when the erythrocytes were extracted in the presence of an anti-oxidant (pyrogallol). Anti-oxidants should be used in the extraction and saponification process when only small samples are available or when only small amounts of carotenoid pigments are present in the material to be extracted.

Carotenoids↗
PubMed2000

[Fusion and expression of the gene encoding human Mn-SOD to anti-CEA single-chain antibody in Escherichia coli].

The gene encoding human manganese-superoxide dismutase (Mn-SOD) was fused to anti-carcinoembryonic antigen single-chain antibody gene to construct the fusion gene, then was ligated into prokaryotic expression vector pET-22b(+), The fusion gene was expressed in E. coli at high level, accounting for 24% of the total bacteria soluble protein; and was characterized by SDS-PAGE and Western-blot analysis; the expression product had the CEA-binding ability in RIA, and also had the SOD activity by pyrogallol autoxidation assay. So, the Mn-SOD moiety retains substantial enzymatic activity, where the ScFv moiety can deliver the fusion protein to tumor, Mn-SOD is a potential tumor-suppressor gene, maybe the fusion protein can provide a new pathway to tumor therapy.

Amino Acid Sequence↗
PubMed2000

Tetrahydroprotoberberines inhibit lipid peroxidation and scavenge hydroxyl free radicals.

AIM: To study the effects of tetrahydroprotoberberines (THPB) on rat liver and brain lipid peroxidation (LPO) and oxygen free radicals generation. METHODS: The malondialdehyde (MDA) levels in rat brain and liver homogenates, induction of MDA by Fe(2+)-Vit C in mitochondria, OH. generation by Fenton reaction, and O2.- generation by pyrogallol oxidation were observed in vitro. RESULTS: (1) THPB lowered the MDA contents in the liver homogenate and mitochondria, and the IC50 values of l-THPB-18 and l-stepholidine (SPD) in the liver mitochondria were 3.1 and 12.7 mumol.L-1 respectively. SPD decreased the MDA contents in the brain homogenate and mitochondria with IC50 values of 102 and 35.0 mumol.L-1 respectively. (2) THPB scavenged OH., and the IC50 values of l-THPB-18 and SPD were 0.21 and 3.8 mumol.L-1 respectively, but no effect on O2.- was observed. CONCLUSION: THPB could reduce the MDA contents and scavenge OH. and THPB-18 was the most potent amongst them.

Animals↗
PubMed2001

[Sensitization to resorcinol in a prescription verrucide preparation: unusual systemic clinical features and prevalence].

BACKGROUND: Resorcinol is a rare sensitizer. In Lorraine, where it is used in high concentrations in an anti-wart ointment, this molecule has induced many cases of allergy. The purpose of this study was to describe clinical features in patients sensitized to resorcinol, to determine the incidence of sensitization in Lorraine and ascertain the occurrence of cross reactions with other phenolic pro-haptens. PATIENTS AND METHODS: The files of all patients sensitized to resorcinol were studied from 1992 to 1999. Over a 20-month period, 983 consecutive patients underwent our standard patch tests where we included resorcinol (1 p. 100 in petrolatum). Co-sensitization with other pro-haptens was studied in all sensitized patients. RESULTS: Sensitization to resorcinol was observed in 0.5 p. 100 of the 983 consecutively tested patients. Contact sensitization was found in 24 patients, who all but one had previously used the anti-wart ointment containing resorcinol. All developed contact eczema on the site of application of the ointment, with generalized urticaria (4 cases), pompholyx (1 case), and generalized papulo-vesicular rash with pompholyx (6 cases). Positive patch tests were observed with resorcinol monobenzoate (15/19 cases), pyrocatechol (7/14 cases), pyrogallol (9/19 cases), salicylaldehyde (2/17 cases), and hydroquinone (6/17 cases). Negative patch tests were observed with phenysalicylate, hexylresorcinol, or fluoresceine. CONCLUSION: Resorcinol should not be applied in high concentrations as it can provoke generalized sensitization and co-sensitization with other pro-haptens.

Administration, Cutaneous↗
PubMed1997

[Investigation on electrochemical behavior of emodin and its application].

Emodin showed a second-order derivative reduction wave with peak potential of -0.75 V (SCE) by single sweep oscillopolarography using H3BO3-Na2B4O7 (pH 8.50) as base solution. The peak height of emodin is proportional to the concentration in the range of 1.42 x 10(-7)-5.7 x 10(-6) mol.L-1 and 7.1 x 10(-6)-7.1 x 10(-5) mol.L-1, respectively. The detection limit is 0.7 x 10(-7) mol.L-1. It can be employed for the determination of emodin in Rheum officinale Baill with satisfaction. The electrochemical behavior of emodin was studied and the electrode reaction mechanism was proposed. In addition, it was found that emodin, aloe-emodin, chrysophanol, rhein and physcion can scavenge superoxide anion radical produced by the autoxidation of pyrogallol. The scavenging activity is in the order: emodin > aloe-emodin > chrysophanol > rhein > physcion.

Anthraquinones↗
PubMedDate not supplied

[Determination of the low protein concentration in biological fluids. Methodological aspects (the use of mathematical analysis)].

We investigated the effect of albumin/globulin ratio on the analytic error of protein determination. Several methods were used: Bradford, Lowry, pyrogallol-red, biuret, and sulfosalicylic acid. Reagents used in Lowry method exhibit higher affinity to globulins, whereas reagents used in other methods have higher affinity to albumins. Although the biuret method demonstrated equal efficiency in determining concentrations of various proteins low sensitivity of this method limits its clinical applicability. For other methods there was non-linear dependence of the analytic error on protein composition in the sample. Combination of two methods for protein determination (using one calibrator) completely removes the analytic error.

Albumins↗