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PubMed1983

A study of the interaction of glycine and its oligohomopeptides with formaldehyde and acetaldehyde under possible primitive earth conditions.

It is established that glycine and glycine oligohomopeptides interact with formaldehyde and acetaldehyde in a homogeneous weak acid medium (pH 3.3-3.7) at mild temperatures (60-80 degrees C) in the absence of inorganic solid substances. Together with the expected serine and threonine, the formation of alanine, glutamic and aspartic acid, norvaline and isoleucine, as well as four non-protein amino acids is also established. It is suggested that the non-protein amino acids are hydroxymethylserine, hydroxymethylthreonine, hydroxymethylaspartic acid and gamma-amino-delta-hydroxyvaleric acid. The modes of formation of all protein and non-protein amino acids are discussed. These results strengthen the probability that similar processes may have been one of the pathways for the prebiotic synthesis of amino acids on primitive Earth.

Acetaldehyde↗
PubMed1980

Microspectrofluorimetric estimation of the formaldehyde-induced fluorescence of the developing main pelvic ganglion of the rat.

The formaldehyde-induced fluorescence (FIF) of the cytoplasm of individual developing neurons of the main pelvic ganglion was recorded microspectrofluorimetrically in order to follow changes in catecholamine (noradrenaline) content during development. For each ganglion, the fluorescence intensity profile was estimated and shown graphically as columns expressing percentage distribution of relative intensities in different intensity classes. During development, the number of weakly fluorescent neurons increases. Treatment with testosterone shifts the profile towards higher intensities in four- and six-week-old animals. Testosterone affected the main pelvic ganglion but not the superior cervical ganglion. The intensity of the cytoplasmic FIF, which correlates with the catecholamine (noradrenaline) content of the object tissue, showed a tendency to decrease during development. This change was not obvious vy visual observation because of the increase in cell size and the toal bulk of the ganglion. Other possible factors affecting visual observation are discussed.

Animals↗
PubMed1987

Determination of the formaldehyde content in fishery products.

The influence of external factors, such as storage temperature and time on the content of free formaldehyde (FA) in fishery products is described. On the basis of the examination of several methods for the determination of free and bound FA, the following procedures are recommended: (1) for measuring free FA, the samples are extracted using 6% perchloric acid at room temperature and the FA content of the extracts is measured by the formation of 3,5-diacetyl-1,4-dihydrolutidine; (2) bound, acid-labile FA is released by steam distillation using 1% sulphuric acid, giving a pH value of about 1. The FA content of the distillates may be determined either by chromotropic acid assay or by the method described for the extracts.

Amino Acids↗
PubMed1996

Evaluation of the stable reaction products of histidine with formaldehyde or with other carbonyl compounds in dairy products.

Combined formaldehyde (FA) can be evaluated in cheese and other dairy products by determining spinacine (6-carboxy-1,2,3,4-tetrahydroimidazopyridine), an imino acid arising from the reaction of FA with the alpha-amino group of histidine. Other carbonyl compounds usually produced by fermentations can react themselves with histidine, forming molecules which interfere with the determination of spinacine. A sensitive (minimum detectable amount, 5 fmol spinacine) and interference-free HPLC method, with precolumn derivatization with o-phtalaldehyde (OPA) and 9-fluorenylmethylchloroformate (FMOC), to evaluate these histidine reaction-compounds in dairy products is described. The clean-up of the FMOC-derivatized sample has been performed for the first time with solid-phase extraction (SPE) on an amino cartridge. The method was applied to samples of casein and differently ripened cheese, the origins of which were either known or commercial, in order to quantify the natural level of spinacine (0.7-2.7 ppm) probably deriving from biogenic FA, and to detect whether FA was used in processing.

Aldehydes↗
PubMed1977

Microspectrography of formaldehyde and fluorescamine-induced fluorescence in rabbit pulmonary neuroepithelial bodies: demonstration of a new, probably polypeptide intracytoplasmic substance.

The microspectrographic analysis of the fluorescence emitted by NEB's in gaseous formaldehyde-fixed lung tissue, posttreated with fluorescamine, revealed the presence of numerous primary amino groups which are clearly different from the serotonin identified in our earlier studies and correspond to a new, probably a polypeptide intracytoplasmic substance.

Amines↗
PubMed1977

Comparison of the production rates of bacteria in the rumen estimated by using labelled live and formaldehyde treated mixed bacterial cells.

The bacteria production rates in the rumen have been estimated by injecting 14C- and 35S-labelled mixed rumen bacteria, either live or killed by treatment with formaldehyde, into the rumen and applying isotope dilution technique. The rate of bacteria production when estimated by using either live- or dead-(protected-)labelled bacterial cells were comparable.

Animals↗
PubMed1976

Formaldehyde-Schiff's reagent as a nucleolar strain.

The use of formaldehyde-Schiff's reagent as a nucleolar stain has been described. Using different digestion procedures, it was confirmed that the stain is specific for RNA. It can be suitably used as a nucleolar stain, particularly in plant materials after a short TCA extraction, which probably extracts the nonbound RNA.

Animals↗
PubMed1990

Analysis of formaldehyde-induced Adh mutations in Drosophila by RNA structure mapping and direct sequencing of PCR-amplified genomic DNA.

Two formaldehyde-induced mutations at the Drosophila Adh locus (Adhfn45 and Adhfn46) were analyzed by determining RNA structures at different developmental stages, polymerase chain reaction (PCR) amplification of the affected genomic regions, and direct sequencing of the resulting double-stranded DNA fragments. Adhfn46 adults and larvae accumulate abundant ADH-like distal (adult) and proximal (larval) transcripts that are shorter than transcripts in wild-type flies by a lesion located in the second ADH protein-coding exon. Direct sequencing of the amplified DNA region showed that Adhfn46 contains a 69-bp in-frame deletion that removes 23 amino acids near one border of the second exon. Consistent with these findings, we observed a shorter ADHfn46 protein present at only 3% of wild-type levels. In contrast, Adhfn45 adults and larvae accumulate much smaller amounts of ADH-like distal and proximal transcripts. Both RNAs have an identical aberration in RNA splicing of the 65-base intron sequence. Direct sequencing of the amplified mutated DNA region showed that Adhfn45 contains a 21-bp deletion that removed and rearranged DNA at the 5' splice junction of the 65-bp intron. No ADH cross-reacting material is detected in Adhfn45 flies. Direct-repeat sequences (3-11 bp) are present flanking and within the mutated DNA regions. The patterns of DNA deletion and deletion accompanied by sequence addition at the mutant sites suggest a slipped mispairing mechanism during DNA replication or repair that involves local DNA homology.

Alcohol Dehydrogenase↗
PubMed1975

A novel inducible formaldehyde dehyrogenase of Pseudomonas sp. (RJ1).

A novel, pyridine-nucleotide-independent, inducible formaldehyde dehydrogenase acitivity was detected in cells of Pseudomonas sp. (RJ1) propagated on methylamine and oxalated. The pH optimum of the dehydrogenase was 7.0. Dichlorophenol-indophenol or potassium ferricyanide served as an electron acceptor. The rate of reduction of these electron acceptors was shown to be stimulated by phenazine methosulfate. The dehydrogenase was inhibited by parahydroxymercuric benzoate and iodoacetamide. This inhibition suggests that the enzyme contains sulfhydryl groups. The stoichiometry of the reaction in terms of oxygen uptake to formate formation was 0.5, which agrees with the theoretical value.

2,6-Dichloroindophenol↗
PubMed1999

Assay of the inhibitory effect of pentachlorophenol and formaldehyde on mycelial growth and development of reproductive structures in Aspergillus niger.

The biological activity of the antifungal agents pentachlorophenol (as sodium pentachlorophenolate) and formaldehyde was evaluated by changes in the development of fungal structures following a placement of test strips inoculated with Aspergillus niger conidia on a nutrient agar with the toxicant. The method allows a quantitative assessment of biological activity measured as the development of vegetative structures (growth of the mycelium) by metric, and the development of reproductive structures (conidia) of A. niger by densitometric methods. The use of test strips with dry conidiospores and the evaluation of the results in physical units represent a simple, rapid, exact and inexpensive test of fungitoxic agents.

Aspergillus niger↗
PubMed1976

Oxidation of methanol, formaldehyde and formic acid by methanol-utilizing yeast.

Methanol-utilizing yeast, Candida boidini 11 Bh, characterized by high tolerance to methanol during growth, displays even higher tolerance when the oxidation rate by intact cells is tested. Low respiration activity is found even at 22% v/v of methanol. The half-saturation constant was 17-18 mM. The half-saturation constants for the two oxidation intermediates, formaldehyde and formic acid were 3.5-4.0 an .d 30-33 mM, respectively. When applied together with standard concentration of methanol, very low concentrations of both intermediates stimulated the oxidation rate. These results are discussed in connection with the relationship between growth and oxidation, the tolerance to high concentrations of inhibitory products and the mechanism of inhibition.

Candida↗
PubMed1994

Excretion of malondialdehyde, formaldehyde, acetaldehyde, acetone and methyl ethyl ketone in the urine of rats given an acute dose of malondialdehyde.

A high pressure liquid chromatographic system (HPLC) has recently been developed for the simultaneous detection of malondialdehyde (MDA), formaldehyde (FA), acetaldehyde (ACT) and acetone (ACON). We have examined the urinary excretion of these four lipid metabolites in the urine of rats following the acute oral administration of MDA (158 mg/kg body weight). During the first 12 h, increases in the urinary excretion of MDA and ACT of approximately 192- and 70-fold, respectively, were observed. The urinary excretion of both MDA and ACT decreased thereafter. An increase in FA excretion was observed only 12-24 h after MDA administration. A significant decrease in ACON relative to control values was observed 12-48 h after MDA treatment. Two new peaks were present in the HPLC chromatograms of urine samples 0-24 h after MDA administration. Both peaks were shown to be due to methyl ethyl ketone (MEK) which appears to be formed as a result of MDA metabolism. The results demonstrate that orally administered MDA is rapidly excreted in the urine, and alters the metabolism and excretion of other lipid metabolites.

Acetaldehyde↗
PubMed1996

Sensory irritation to mixtures of formaldehyde, acrolein, and acetaldehyde in rats.

Sensory irritation of formaldehyde (FRM), acrolein (ACR) and acetaldehyde (ACE) as measured by the decrease in breathing frequency (DBF) was studied in male Wistar rats using nose-only exposure. Groups of four rats were exposed to each of the single compounds separately or to mixtures of FRM, ACR and/or ACE. Exposure concentrations of the mixtures were chosen in such a way that summation of the effects of each chemical would be expected not to exceed 80% reduction of the breathing frequency. FRM, ACR and ACE appeared to act as sensory irritants as defined by Alarie (1966, 1973). With FRM and ACR desensitization occurred, whereas with ACE the breathing frequency gradually decreased with increasing exposure time (up to 30 min). For mixtures, the observed DBF was more pronounced than the DBF for each compound separately, but was less than the sum of the DBFs for the single compounds. A model for three compounds competing for the same receptor was applied to predict the DBF of mixtures of FRM, ACE and ACR. The results also showed that with mixtures no desensitization occurred; in fact, the breathing frequency further decreased in the last 15 min of exposure. These observations were similar to those found for ACE alone, and might have been caused by effects on the upper respiratory tract. The results of the present study allow the conclusion that sensory irritation in rats exposed to mixtures of irritant aldehydes is more pronounced than that caused by each of the aldehydes separately, and that the DBF as a result of exposure to a mixture could well be predicted using a model for competitive agonism, thus providing evidence that the combined effect of these aldehydes is basically a result of competition for a common receptor (trigeminal nerve).

Acetaldehyde↗
PubMed1998

Improved mRNA in situ hybridization on formaldehyde-fixed and paraffin-embedded tissue using signal amplification with different haptenized tyramides.

We report an optimized in situ hybridization (ISH) protocol with a rapid signal amplification procedure based on catalyzed reporter deposition (CARD) to increase the sensitivity of non-isotopic mRNA ISH on formaldehyde-fixed and paraffin-embedded tissue. The CARD method is based on the deposition of haptenized tyramide molecules in the vicinity of hybridized probes catalyzed by horseradish peroxidase. Commercially available and newly synthesized haptenized tyramides, including digoxigenin-, biotin-, di- and trinitrophenyl- as well as fluorescein-tyramide, were compared. The haptenized tyramides were visualized using peroxidase conjugated anti-hapten antibodies followed by the diaminobenzidine reaction. As a test system, we applied digoxigenin-labeled oligonucleotides to detect insulin and vasoactive intestinal polypeptide mRNA in pancreatic endocrine tumors and liver metastases. Our results indicate that specificity, sensitivity, and applicability of oligonucleotide mRNA ISH can be significantly improved by using chemically digoxigenin-labeled oligonucleotide probes and signal amplification by CARD. Furthermore, all tested tyramides provided approximately equal amplification efficiency. In conclusion, CARD signal amplification should further promote mRNA ISH studies on paraffin-embedded tissues and allow for multiple-target nucleic acid detection in situ.

Dinitrophenols↗
PubMed2005

Late complications following surgery for type A acute aortic dissection using gelatin-resorcin-formaldehyde glue: report of two cases.

Gelatin-resorcin-formaldehyde (GRF) glue has been widely applied during operations for acute aortic dissection (AAD). At our institution, GRF glue was applied in 40 patients who underwent surgical procedures for AAD from 1995, two of whom needed a reoperation because of the development of a redissection and/or a pseudoaneurysm at the anastomotic sites. The operative findings and histological examinations suggested that the application of GRF glue during the initial operations might be related to the development of a redissection and/or a pseudoaneurysm.

Aged↗
PubMed2006

Determination of Henry's law constant of formaldehyde as a function of temperature: application to air-water exchange in Tahtali Lake in Izmir, Turkey.

The Henry's law constant (H) is an important parameter in predicting the transport, behavior and fate of organic compounds in environment. H is also required to model the air-water exchange of chemicals. Henry's law constant of formaldehyde (HCHO) was determined at six temperatures (50, 40, 30, 20, 10, and 5 degrees C) using a bubble-column technique. The apparent Henrys law constant (H*) values were strongly correlated to inverse of temperature (1/T, K) and the following relationship was obtained: In H* = (-1,641.3/T)-3.089. Seven concurrent ambient air and aqueous samples were also collected between October 11-17, 2005 at a sampling site located on the shoreline of Tahtali dam Lake in Izmir, Turkey to determine the magnitude and direction (deposition or gas-out) of HCHO flux. In all cases, the modeled gas-phase flux was positive (average +/- SD, 3,181 +/- 408 microg m(-2) day(-1)) indicating that atmospheric HCHO deposited to the Tahtali Lake.

Air↗
PubMed1983

A simple spectrophotometric determination of formaldehyde and other aldehydes: application to periodate-oxidized glycol systems.

A simple, rapid, and sensitive spectrophotometric assay procedure for the determination of as low as 2 microM solutions of formaldehyde and acetaldehyde using an alkaline 4-amino-5-hydrazino-3-mercapto-1,2,4-triazole reagent is described. The method is particularly useful for determination of these aldehydes (0.5-50 nmol) when produced by the periodate oxidation of various glycols and can be applied to the assay of dilute solutions of sugars or polyols.

Acetaldehyde↗