Abstract  BACKGROUND: During surgical treatment for acute type A aortic dissection, gelatin-resorcin-formalin glue is generally applied and its efficacy has been reported. However, some late complications that are potentially associated with this glue have also been reported. In the present study, we reviewed our experiences of treatment for acute type A aortic dissection and late complications that occurred in the anastomotic site, which needed a reoperation.

METHODS: From October 1994 to August 2005, 68 patients underwent emergency surgery for acute type A aortic dissection. Gelatin-resorcin-formalin glue was applied to 56 (82.4%) of these patients at one or both of the distal and proximal anastomosis sites.

RESULTS: Eight (11.8%) patients died in hospital within 30 days after the operation, among which two patients already had cerebral complications prior to the surgery. There were five late deaths from causes unrelated to cardiac events. Five patients developed an aortic pseudoaneurysm at the anastomotic site and underwent a late reoperation. All of these patients had been treated with gelatin-resorcin-formalin glue during the previous operation. Histologic examination of the resected aortic wall after the reoperation revealed tissue necrosis, severe local inflammation, and organization of old thrombi at the site of the glue application.

CONCLUSIONS: Late complications after the use of gelatin-resorcin-formalin glue may occur with a certain amount of risk, suggesting its toxicity for aortic tissue. Therefore, proper use of this glue and close follow-up of the patients are strictly required.

Abstract  Microsomes and reconstituted systems containing cytochrome P450 can oxidize glycerol to formaldehyde in a reaction catalyzed by an oxidant produced from the interaction of nonheme iron with H2O2. To evaluate the mechanism for this oxidation, the generation of glycerol radicals by various systems was compared to rates of formaldehyde production from glycerol. Photolysis of H2O2, oxidation of xanthine by xanthine oxidase in the presence of iron catalysts, or NADPH-dependent microsomal electron transfer in the presence of ferric-EDTA produced hydroxyl radicals. In the presence of glycerol these reaction systems produced DMPO-glycerol radical adducts which were detected by ESR spectroscopy. Despite the production of .OH and glycerol spin-trapped adducts by these reaction systems, very low amounts or nondetectable amounts of formaldehyde were produced from the glycerol. However, significant amounts of formaldehyde were observed when microsomes were incubated in the presence of ferric ammonium sulfate or ferric-ATP, although .OH production was lower with these iron catalysts than with ferric-EDTA. These results fail to support correlation between .OH production and oxidation of glycerol to formaldehyde. Under conditions in which glycerol was oxidized to formaldehyde, no glycerol radical species could be observed with DMPO as the spin-trapping agent. These results suggest the oxidant (not .OH) derived from the interaction of H2O2 with iron apparently cleaves glycerol to formaldehyde without the formation of a radical intermediate. Alternatively, the radical intermediate may be produced at a too low concentration to be detected or the radical intermediate may not be formed as a free species and therefore cannot be spin-trapped.(ABSTRACT TRUNCATED AT 250 WORDS)

Abstract  BIOSIS COPYRIGHT: BIOL ABS. Glycerol can be oxidized to formaldehyde by microsomes in a reaction that is dependent on cytochrome P-450. An oxidant derived from the interaction of H2O2 with iron was responsible for oxidizing the glycerol, with P-450 suggested to be necessary to produce H2O2 and reduce non-haem iron. The effect of paraquat on formaldehyde production from glycerol and whether paraquat could replace P-450 in supporting this reaction were studied. Paraquat increased NADPH-dependent microsomal oxidation of glycerol; the stimulation was inhibited by glutathione, catalase, EDTA and desferrioxamine, but not by superoxide dismutase or hydroxyl-radical scavengers. The paraquat stimulation was also inhibited by inhibitors, substrate and ligand for P-4502E1 (pyrazole-induced P-450 isozyme), as well as by anti-(P-4502E1) IgG. These results suggest that P-450 still played an important role in glycerol oxidation, even in the presence of paraquat. Purified NADPH-cytochrome P450 reductase did not o

Abstract  Analysis of the activity and structure of lower vertebrate alcohol dehydrogenases reveals that relationships between the classical liver and yeast enzymes need not be continuous. Both the ethanol activity of class I-type alcohol dehydrogenase (alcohol:NAD+ oxidoreductase, EC and the glutathione-dependent formaldehyde activity of the class III-type enzyme [formaldehyde:NAD+ oxidoreductase (glutathione-formylating), EC 1.2.1.1] are present in liver down to at least the stage of bony fishes (cod liver: ethanol activity, 3.4 units/mg of protein in one enzyme; formaldehyde activity, 4.5 units/mg in the major form of another enzyme). Structural analysis of the latter protein reveals it to be a typical class Ill enzyme, with limited variation from the mammalian form and therefore with stable activity and structure throughout much of the vertebrate lineage. In contrast, the classical alcohol dehydrogenase (the class I enzyme) appears to be the emerging form, first in activity and later also in structure. The class I activity is present already in the piscine line, whereas the overall structural-type enzyme is not observed until amphibians and still more recent vertebrates. Consequently, the class I/III duplicatory origin appears to have arisen from a functional class III form, not a class I form. Therefore, ethanol dehydrogenases from organisms existing before this duplication have origins separate from those leading to the "classical " liver alcohol dehydrogenases. The latter now often occur in isozyme forms from further gene duplications and have a high rate of evolutionary change. The pattern is, however, not simple and we presently find in cod the first evidence for isozymes also within a class III alcohol dehydrogenase. Overall, the results indicate that both of these classes of vertebrate alcohol dehydrogenase are important and suggest a protective metabolic function for the whole enzyme system.

Abstract  The capacity of the vascular enzyme, semicarbazide-sensitive amine oxidase (SSAO), to metabolize methylamine to the potentially toxic product, formaldehyde, was tested using rat aortic homogenates and purified porcine aortic SSAO. Formaldehyde production in incubations of enzyme source with methylamine (1 mM) was detected by high performance liquid chromatography and product was confirmed by desorption chemical ionization mass spectrometry (DCI-MS). Inhibitor studies using the specific SSAO inhibitor semicarbazide and the monoamine oxidase inhibitor pargyline indicate that SSAO is responsible for metabolism of methylamine to formaldehyde. These results suggest the possibility that elevated methylamine found in several pathologic states (such as uremia and diabetes mellitus), or generated from exogenous sources, could result in overproduction of formaldehyde in tissues with high SSAO activity, especially blood vessels.

Abstract  The class III human liver alcohol dehydrogenase, identical to glutathione-dependent formal-dehyde dehydrogenase, separates electrophoretically into a major anodic form (chi-1) of known structure, and at least one minor, also anodic but a slightly faster migrating form (chi-2). The primary structure of the minor form isolated by ion-exchange chromatography has now been determined. Results reveal an amino acid sequence identical to that of the major form, suggesting that the two derive from the same translation product, with the minor form modified chemically in a manner not detectable by sequence analysis. This pattern resembles that for the classical alcohol dehydrogenase (class I). Hence, the chi-1/chi-2 multiplicity does not add further primary forms to the complex alcohol dehydrogenase system but shows the presence of modified forms also in class III.

Abstract  Rat liver microsomes can oxidize glycerol to formaldehyde. This oxidation is sensitive to catalase and glutathione plus glutathione peroxidase, suggesting a requirement for H2O2 in the overall pathway of glycerol oxidation. Hydrogen peroxide can not replace NADPH in supporting glycerol oxidation; however, added H2O2 increased the NADPH-dependent rate. Ferric chloride or ferric-ATP had no effect on glycerol oxidation, whereas ferric-EDTA was inhibitory. Certain iron chelators such as desferrioxamine, EDTA or diethylenetriaminepentaacetic acid, but not others such as ADP or citrate, inhibited glycerol oxidation. The inhibition by desferrioxamine could be overcome by added iron. Neither superoxide dismutase nor hydroxyl radical scavengers had any effect on glycerol oxidation. With the exception of propyl gallate, several antioxidants which inhibit lipid peroxidation had no effect on formaldehyde production from glycerol. The inhibition by propyl gallate could be overcome by added iron. In contrast to glycerol, formaldehyde production from dimethylnitrosamine was not sensitive to catalase or iron chelators, thus disassociating the overall pathway of glycerol oxidation from typical mixed-function oxidase activity of cytochrome P450. These studies indicate that H2O2 and nonheme iron are required for glycerol oxidation to formaldehyde. The responsible oxidant is not superoxide, H2O2, or hydroxyl radical. Cytochrome P450 may function to generate the H2O2 and reduce the nonheme iron. There may be additional roles for P450 since rates of formaldehyde production by microsomes exceed rates found with model chemical systems. Elevated rates of H2O2 production by certain P450 isozymes, e.g., P450 IIE1, may contribute to enhanced rates of glycerol oxidation.

Abstract  Formaldehyde-treated serum albumin (f-Alb) is known to be taken up and degraded by sinusoidal liver cells via receptor-mediated endocytosis. We report that125I-labeled f-Alb (125I-f-Alb) binding to human placental brush-border membranes also occurs. This binding reached equilibrium within 40 min at 37°C. Kinetic studies demonstrated the presence of saturable binding with an apparent Kd of 2.1 μg of f-Alb/ml and 0 maximal binding of 2.3 μg/mg of membrane protein at pH 7.5. Maximal binding was observed at between pH 7.5 and 8.0.125I-f-Alb binding to the membranes was little inhibited by a 1000-fold molar excess of ovalbumin, human apo-transferrin and native bovine serum albumin. No binding was observed with membranes which had been pretreated with proteinase or trypsin. This f-Alb receptor was extremely heat-stable, since the binding was not abolished even by pretreatment of the membranes at 78°C for 30 min. EDTA, Ca2+ and Mg2+ had no effect on125I-f-Alb binding, so the binding was independent of divalent cations. These data suggest that a receptor specific for f-Alb exists on human placental brush-border membranes of syncytial trophoblasts.

Abstract  BIOSIS COPYRIGHT: BIOL ABS. RRM

Abstract  Crotonaldehyde was oxidized by disrupted rat liver mitochondrial fractions or by intact mitochondria at rates that were only 10 to 15% that of acetaldehyde. Although a poor substrate for oxidation, crotonaldehyde is an effective inhibitor of the oxidation of acetaldehyde by mitochondrial aldehyde dehydrogenase, by intact mitochondria, and by isolated hepatocytes. Inhibition by crotonaldehyde was competitive with respect to acetaldehyde, and the Ki for crotonaldehyde was about 5 to 20 microM. Crotonaldehyde had no effect on the oxidation of glutamate or succinate. Very low levels of acetaldehyde were detected during the metabolism of ethanol. Crotonaldehyde increased the accumulation of acetaldehyde more than 10-fold, indicating that crotonaldehyde, besides inhibiting the oxidation of added acetaldehyde, also inhibited the oxidation of acetaldehyde generated by the metabolism of ethanol. Formaldehyde was a substrate for the low-Km mitochondrial aldehyde dehydrogenase, as well as for a cytosolic, glutathione-dependent formaldehyde dehydrogenase. Crotonaldehyde was a potent inhibitor of mitochondrial oxidation of formaldehyde, but had no effect on the activity of formaldehyde dehydrogenase. In hepatocytes, crotonaldehyde produced about 30 to 40% inhibition of formaldehyde oxidation, which was similar to the inhibition produced by cyanamide. This suggested that part of the formaldehyde oxidation occurred via the mitochondrial aldehyde dehydrogenase, and part via formaldehyde dehydrogenase. The fact that inhibition by crotonaldehyde is competitive may be of value since other commonly used inhibitors of aldehyde dehydrogenase are irreversible inhibitors of the enzyme.

Abstract  The uptake and degradation of 125I-labeled formaldehyde-denatured serum albumin in nonparenchymal rat liver cells were studied in vitro. Nonparenchymal cells bound formaldehyde-denatured serum albumin at two types of binding site, one with a high affinity and one a low affinity. The number of high affinity binding sites was approx. 10(5) per cell and the association constant, Ka 10(8) M-1. Inhibition of protein synthesis with cycloheximide did not affect the uptake and degradation of formaldehyde-denatured serum albumin suggesting reutilization of the binding sites. The presence of monensin-reduced uptake and degradation to less than 10% of control values. Pronase treatment of nonparenchymal liver cells completely abolished the uptake and degradation of the ligand. The uptake mechanism was not specific for formaldehyde-denatured serum albumin. Unlabeled acetylated, as well as malondialdehyde treated, serum albumin reduced the uptake of 125I-labeled formaldehyde-denatured serum albumin as effectively as unlabeled formaldehyde-denatured serum albumin itself.

Abstract  For the inhibition of spontaneous N epsilon-methylation and N epsilon-formylation reactions between L-lysine and formaldehyde, L-ascorbic acid proved to be most suitable. The inhibition was not complete unless the molar concentration of ascorbic acid exceeded that of formaldehyde. T.l.c., potentiometric titration, n.m.r. spectroscopy and radiometric analysis were applied in the study of the inhibition process. Formaldehyde was reduced by L-ascorbic acid to ethylene glycol.

Abstract  The uptake of formaldehyde-treated 125I-labelled human serum albumin in rat hepatocytes and nonparenchymal liver cells was measured in vivo and in vitro. Isolated liver cells were prepared by treating the perfused liver with collagenase. Purified hepatocytes and nonparenchymal cells were obtained by differential centrifugation. Human serum albumin was found to be taken up exclusively or almost exclusively by nonparenchymal cells in vitro and in vivo (after intravenous injection). The maximal rate of human serum albumin-uptake in vitro was comparable to that in vivo. Nonparenchymal cells degraded human serum albumin in vitro as indicated by release of trichloroacetic acid-soluble radioactivity. Degradation started about 20-30 min after addition of human serum albumin to cells and rate of degradation was proportional to rate of uptake. Human serum albumin-degradation could be studied without interference of concurrent uptake by separating cells that had been preincubated with human serum albumin from the medium and then reincubating them with human serum albumin-free medium. The lag phase before human serum albumin-degradation starts and the inhibitory effect of chloroquine on degradation indicate that human serum albumin is degraded in lysosomes. The data obtained show that enzymatically prepared nonparenchymal liver cells retain their endocytic activity in vitro. Denatured human serum albumin should be useful both as a marker for rat liver macrophages and for the study of intracellular proteolysis in these cells.

Abstract  Natural organic matter (NOM) in the filtrated surface water from a water treatment plant was isolated and fractionated into six types of fractions. These fractions were ozonated at typical ozone dose and reaction time. The yields of several small molecular ozonation by-products, such as, aldehydes, ketones and ketoacids, were monitored after ozonation of the individual NOM fractions. The results showed that formaldehyde and pyruvic acid had the maximal yields among the aldehydes and ketoacids, respectively. Hydrophobic neutral (HON) produced the most significant yield of the ozonation by-products with the specific yield of formaldehyde up to 70.58% of the specific yields and pyruvic acid being 103.2 microg/mg. The hydrophobic NOM fractions produced higher yields of these by-products than the hydrophilic fractions. For example, HON and hydrophobic acid (HOA) produced much higher yields of the ozonation by-products than other fractions. Aldehydes and ketones from HON and HOA and ketoacids from the two fractions accounted for 55.56% and 60% of the ozonation by-products from all the NOM, respectively. Lower production of these by-products was also observed for the basic fractions compared to the acidic and neutral ones. HON and HOA were more biodegradable after ozonation, because their ozonation by-products contributed much higher amount of DOC to the final DOC after ozonation.

Abstract  The use of advanced oxidation processes (AOPs) to remove pollutants in various water treatment applications has been the subject of study for around 30 years. Most of the available processes (Fenton reagent, O3 under basic conditions, O3/H2O2, O3/UV, O3/solid catalyst, H2O2/M(n+), H2O2/UV, photo-assisted Fenton, H2O2/solid catalyst, H2O2/NaClO, TiO2/UV etc.) have been investigated in depth and a considerable body of knowledge has been built up about the reactivity of many pollutants. Various industrial applications have been developed, including ones for ground remediation (TCE, PCE), the removal of pesticides from drinking water, the removal of formaldehyde and phenol from industrial waste water and a reduction in COD from industrial waste water. The development of such AOP applications has been stimulated by increasingly stringent regulations, the pollution of water resources through agricultural and industrial activities and the requirement that industry meet effluent discharge standards. Nevertheless, it is difficult to obtain an accurate picture of the use of AOPs and its exact position in the range of water treatment processes has not been determined to date. The purpose of this overview is to discuss those processes and provide an indication of future trends.

Abstract  This paper describes a study of oxidation of diethylene glycol (DEG) by ozone and modified Fenton process (hydrogen peroxide and ferric salt mixture) in aqueous solution. Both oxidation processes were able to oxidize relatively high concentrations of DEG effectively. DEG reacted primarily through hydroxyl radical produced by decomposition of ozone, and about 3 mol of ozone were consumed per mole of DEG removed during the process. For modified Fenton oxidation, stepwise addition of hydrogen peroxide (H2O2) and ferric salt (Fe(III)) resulted in much higher removal of DEG than one-time pulse addition of the chemicals. The extent of DEG removal increased with increasing concentrations of both H2O2 and Fe(III). Oxidant consumption per mole of DEG oxidized was one order of magnitude higher for hydrogen peroxide than those observed for ozone. Overall, ozonation produced higher concentrations of aldehydes, and modified Fenton treatment produced higher concentrations of carboxylic acids for the same levels of DEG oxidation. The major products of ozonation were glycolaldehyde, glyoxal, formaldehyde, acetaldehyde, and acetic, formic, pyruvic, oxalic and glyoxalic acids. The major products of modified Fenton oxidation were formaldehyde, and formic and acetic acids.

Abstract  The induction of ornithine-decarboxylase (ODC) activity and DNA synthesis was studied in the glandular stomach mucosa of rats after gastric intubation of formaldehyde (50000) (FA). Male Fischer-rats were given doses of FA ranging from 11 to 110mg/kg body weight by gastric intubation between 8 and 10 in the morning following a restricted amount of food overnight. In a second experiment, they were given the FA at 6 pm. The maximum increase in ODC activity was a 100 fold increase noted after 16 hours. The maximum increase in DNA synthesis was a 49 fold increase after 16 hours in the pyloric mucosa of the stomach. Even doses lower than 75mg/kg, FA induced ODC activity and DNA synthesis in the pyloric mucosa in this study. All the glandular stomach carcinogens and tumor promoters examined have thus far been found to induce ODC activity and stimulate DNA synthesis in the glandular stomach mucosa. The results of this study indicate that inductions of ODC activity and DNA synthesis are useful markers of possible tumor promoting activity in the glandular stomach mucosa. The authors suggest the possibility that stomach tumor promoters can be predicted by this in-vivo short term assay.

Abstract  Glutaraldehyde-formaldehyde fixed undecalcified alveolar bone from 7-day-old rats was prepared for light and electron microscopy. Colloidal lanthanum was used as an ultrastructural tracer, and both random and semi-serial sections were examined. Lanthanum penetrated the infoldings of the ruffled border and some nearby vacuoles and vesicles. The majority of vacuoles and vesicles were lanthanum-free. Some osteoclast profiles contained a large vacuole with a cell enclosed in its interior. The enclosed cell exhibited an irregular nucleus containing condensed peripheral chromatin, intact cytoplasmic organelles, conspicuous rough endoplasmic reticulum and large blebs on the cell surface. These features are characteristic of osteoblasts or bone-lining cells or immature osteocytes which may be undergoing apoptosis or necrosis. The observation of remnants of cellular structures within internalized osteoclast vacuoles, together with the above results, suggests that osteoclasts engulf and probably degrade dying osteoblasts/bone-lining cells or immature osteocytes.

Abstract  Among the contaminants of water, soil and air the number of mutagenic and carcinogenic substances is increasing. For the assessment of health risk connected with the simple and cheap methods are necessary which could detected and measure the mutagenicity of these substances. The widely used tests using prokaryotes give negative results in the tests of certain substances which are carcinogenic in mammals. In the case of benzene and acetaldehyde Ames test gives false negative results, and in the case of formaldehyde the results are equivocal. An advantage of fruit fly Drosophila melanogaster used for this purpose is that its cell structures, enzymes and metabolic processes are similar to those of mammals. For the demonstration of mutagenicity of benzene, acetaldehyde and formaldehyde the test of somatic mutation and recombination SMART was carried out in these flies. The results confirmed the usefulness of the SMART test for the demonstration of the mutagenicity of contaminants in the environment.

Abstract  The detailed knowledge of the three-dimensional (3D) organization of the nervous tissue provides essential information on its functional elucidation. We used serial block-face scanning electron microscopy with focused ion beam (FIB) milling to reveal 3D morphologies of the mossy fiber rosettes in the mice cerebellum. Three-week-old C57 black mice were perfused with a fixative of 1% paraformaldehyde/1% glutaraldehyde in phosphate buffer; the cerebellum was osmicated and embedded in the Araldite. The block containing granule cell layer was sliced with FIB and observed by field-emission scanning electron microscopy. The contrast of backscattered electron image of the block-face was similar to that of transmission electron microscopy and processed using 3D visualization software for further analysis. The mossy fiber rosettes on each image were segmented and rendered to visualize the 3D model. The complete 3D characters of the mossy fiber rosette could be browsed on the A-Works, in-house software, and some preliminary quantitative data on synapse of the rosette could be extracted from these models. Thanks to the development of two-beam imaging and optimized software, we could get 3D information on cerebellar mossy fiber rosettes with ease and speedily, which would be an additive choice to explore 3D structures of the nervous systems and their networks.