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PubMedDate not supplied

Determination of formaldehyde and other aldehydes in industrial surfactants by liquid chromatographic separation of their respective 2,4-dinitrophenylhydrazone derivatives.

A rapid and simple method for the determination of formaldehyde, acetaldehyde, and propionaldehyde in surfactants by derivatization with 2,4-dinitrophenylhydrazine (DNPH) has been developed. Samples are prepared in small vials containing a solution of DNPH and acetonitrile. This procedure allows direct injection of an aliquot of the sample into a liquid chromatograph (LC) for analysis. Separation and quantitation of the derivatives can be performed using reverse-phase liquid chromatography. Detection limits for formaldehyde, acetaldehyde, and propionaldehyde are 0.1, 0.1, and 0.5 micrograms/g, respectively, for a 1 g sample of the surfactant. The technique has been applied to other ethoxylated and propoxylated polymeric materials with equal success.

Aldehydes↗
PubMed1987

[Amino acids as catalysts of the binding reaction of formaldehyde with adenine residue in polyadenylic acid].

Binding of formaldehyde and amino acids (Gly, Lys and Leu) with poly(A), poly(G), and poly(C) has been investigated in comparison with treatment with formaldehyde alone. It was found that in the case of poly(A) amino acids were found to catalyze the N-hydroxymethylation reaction on exocyclic amino groups of adenine. For example, at 20 degrees C and pH 6.0 the rate of this reaction increased about 10 fold in the presence of glycine.

Adenine↗
PubMedDate not supplied

Electron capture gas chromatographic determination of traces of formaldehyde in milk as the 2,4-dinitrophenylhydrazone.

A quantitative method is described for the determination of formaldehyde in milk by packed-column gas chromatography and electron capture detection. Aldehyde derivatization was carried out in situ with 2,4-dinitrophenylhydrazine followed by extraction and analysis using an external standard. Average recoveries of 96.3 +/- 1.6% were characteristic of the chromatographic method with an estimated detection limit of 0.026 mg/kg. The technique was applied to determination of formaldehyde in milk from cows consuming a formalin-treated feedstuff.

Animals↗
PubMed1979

[Polarographic method of determining formaldehyde in air].

A rapid polarographic method for determination of formaldehyde microconcentrations in air has been developed. The method is highly sensitive - 0,5 cg/ml, which is 10 times higher than the sensitivity of the known methods now at use, with standard deviation less than 1.0. It is formaldehyde-selective - other saturated and unsaturated aldehydes, ketones, phenol, furfurol etc. do not interfere the determination. Sampling takes 15-20 min, polarographic analysis - 1 to 2 min. The method has been tested under conditions of production and proved to be highly reproducible and comparable with the colorimetric chromotropic acid technique.

Air Pollutants↗
PubMed1987

[Effect of formaldehyde on brain carbohydrate metabolism].

The use of formaldehyde makes it possible to decrease the speed of the energy metabolism in the brain without any significant pathological chemical changes in the functional state of the cardiovascular system. The given effect of formaldehyde may account for the attenuation of hypoxic and ischemic disturbances.

Animals↗
PubMed1985

Urea formaldehyde foam insulation: defusing a timebomb.

With the onset of the energy crisis in the 1970's, thousands of homeowners insulated their homes with Urea Formaldehyde Foam Insulation (UFFI). The discovery that UFFI releases formaldehyde, a carcinogen and irritant, prompted various state and federal responses to this problem. This Note reviews those responses and concludes that a ban on the sale of UFFI, coupled with a removal and repurchase program, is the most effective solution from the standpoint of consumer health.

Construction Materials↗
PubMed1985

Formaldehyde-induced fluorescence in melanomas and other lesions. Diagnostic significance and mechanism of fluorescence.

We have investigated 40 cases of malignant melanoma (MM) and 81 other lesions including benign melanocytic neoplasms, other malignancies with a potential for confusion with MM, and tissues with biogenic amine-synthesizing apparatus for induction of formaldehyde-induced fluorescence (FIF). Unstained sections were examined with an ultraviolet light source for yellowish fluorescence. Twenty-four of 27 primary cutaneous MMs and 11 of 13 metastatic MMs were positive. Formaldehyde-induced fluorescence was quenched by prior sodium borohydride treatment, suggesting monoamine origin. None of the ten intradermal, five junctional, or three blue nevi showed FIF, but two of eight compound nevi and two of six spindle cell nevi were positive for FIF. One of six large-cell undifferentiated carcinomas was positive; none of six mesenchymal sarcomas were positive; one of seven histiocytic lymphomas showed weak, granular, cytoplasmic fluorescence. Two of five carcinoid tumors and one case of medullary carcinoma of thyroid showed FIF. We conclude that FIF is a simple, reproducible, technique for aiding in the diagnosis of amelanotic melanomas.

Diagnosis, Differential↗
PubMed1985

Hybridization selection of covalent nucleic acid-protein complexes. 2. Cross-linking of proteins to specific Escherichia coli mRNAs and DNA sequences by formaldehyde treatment of intact cells.

Proteins cross-linked to pBR322 mRNAs and DNA by formaldehyde treatment of intact Escherichia coli cells have been detected with the use of a novel detection method. Among the proteins cross-linked to pBR322 mRNAs were S1, S21, and at least six other proteins of the small ribosomal subunit, initiation factor 1, elongation factor (EF) Tu, and very small amounts of EF-G and EF-Ts. The single strand binding protein, the HU-proteins, and RNA polymerase subunits alpha and beta were among the proteins cross-linked to pBR322 DNA. The results obtained suggest that the procedures described, can also be used to study interactions between different nucleic acid-bound polypeptides. The results are discussed in relation to the working mechanism of formaldehyde, and are compared to the results obtained with cross-linking induced by ultraviolet light. The methods presented should also be of use for the study of nucleic acid-protein interactions in other organisms.

Bacterial Proteins↗
PubMedDate not supplied

[Kinetic principles of the process of formaldehyde biodegradation].

The kinetics of formaldehyde biodegradation by Pseudomonas fluorescens was studied under the conditions of batch cultivation. The process was shown to depend on the substrate, biomass and metabolites concentrations. Their combined action is satisfactorily described by the equation (formula; see text) where Vmax = 3.23 g/g/h, Ks = 2.52 g/l and Kx = 10.2 g/l. The equation is adequate as was demonstrated in experiments in which the organism was cultivated under the continuous conditions on the formaldehyde-containing sewage from the production of antibiotics.

Biodegradation, Environmental↗
PubMed1985

In situ cross-linking of androgen receptors to nuclear acceptor sites of rat prostate with formaldehyde.

Androgen receptors were attached covalently in situ to their nuclear acceptor sites with the contact site cross-linker, formaldehyde. Chromatin, prepared from sonicated nuclei of rat prostate, was labeled by isotope exchange with [3H]dihydrotestosterone and found to contain 19,000 +/- 900 (mean +/- S.E.) salt-extractable androgen receptors/nucleus which sedimented in the 3-4 S region of 7.6-76% (v/v) glycerol gradients and at a density of approximately 1.28-1.35 g/ml in CsCl gradients. After incubation of the chromatin with 0.5% (w/v) formaldehyde for 1 h at 4 degrees C, there was a 90% reduction in the concentration of free androgen receptors and an increase in the density of the androgen binding sites recovered from CsCl gradients. Extensive digestion of the cross-linked chromatin with micrococcal nuclease liberated 18% of the androgen receptors as 3-4 S entities and caused an overall decrease in the density of the receptor-acceptor complexes. Ribonuclease digestions had no effect on the androgen receptors cross-linked to chromatin. Mild digestion of the cross-linked preparations with trypsin, alone or in combination with micrococcal nuclease, resulted in the release of 74% and 97% of the androgen receptors, respectively. Together, these findings imply that two classes of receptor-acceptor complexes are present in prostatic chromatin--one, containing about 20% of the androgen receptors in which the receptors are in direct contact with DNA but not with proteins and the other, containing most of the androgen receptors in which the receptors are adjacent to acceptor proteins but not to DNA.

Animals↗
PubMedDate not supplied

[Effect of formaldehyde on a Pseudomonas fluorescens strain].

The strain of Pseudomonas fluorescens was isolated from active ooze and was capable of growth on a medium containing 100 mg/litre of formaldehyde. As a result of stepwise selection, a variant of Ps. fluorescens 27 oxidizing 250 mg/litre of formaldehyde was obtained. It differed from the parent strain in cultural, morphological, and biochemical properties.

Formaldehyde↗
PubMedDate not supplied

Results of the single-radial-diffusion test with formaldehyde-treated influenza virus.

We found reduced values for formaldehyde-treated influenza virus in the single-radial-diffusion test by comparison with non-treated virus. The reduction correlates with the formaldehyde concentration. Hemagglutination and neuraminidase activities were not affected by the same treatment. We therefore suggest that this reduction is not based on antigen destruction.

Formaldehyde↗
PubMed1977

Effect of hydrolyzed formaldehyde-treated RNA on neoplastic and normal human cells.

Alkaline hydrolysate of dialyzed formaldehyde-treated RNA, in which 39% of purine nucleotides are modified to methylene bis derivatives (R-CH2-R'), displays cytotoxic activity toward cultured human tumor cells. The alkaline hydrolysate of dialyzed formaldehyde-treated RNA is substantially less toxic to normal human embryonic cells. There is a correlation between the cytotoxic effect and cell growth rate, which has been traced by quantitative tests.

Antineoplastic Agents↗
PubMedDate not supplied

[Effect of a therapeutic and prophylactic diet enriched with thiamine and calcium pantothenate on the acetylating capacity of the body of workers engaged in the manufacture of phenol-formaldehyde resins].

The present investigation uncovered certain changes in the intensity of the acetylating processes, in the blood and urine levels of the pyruvic acid and in the urinary excretion of thiamine in a number of persons engaged in the production of phenol-formaldehyde resins. An enrichment of medico-prophylactic ration No 4 with thiamine and calcium pantothenate led to normalization of the study characteristics. The results thus made available bear proof to the prophylactic effectiveness of a supplementary vitaminization of the special diet accorded to workers handling phenol-formaldehyde resins.

Acetylation↗
PubMed1981

Study of some properties of ABO test sera by using the method of phagocytosing erythrocytes treated with formaldehyde in vitro.

By using the method of phagocytosis of erythrocytes treated with formaldehyde against human test sera, an indirect conclusion on the quantity of IgG antibodies in the used sera could be made. Combined tests of 0, A1 and B blood group with erythrocytes treated with formaldehyde against test sera 0 (alpha + beta), A (beta) and B (alpha) and AB (0) sera from non-immunized and immunized with anatoxin from staphylococcus aureus donors were made. The strongest phagocytosis was observed when A1 and B erythrocytes with 0 (alpha + beta) sera and A1 erythrocytes with AB (0) sera from immunized with anatoxin donors were combined. A weaker phagocytosis took place when erythrocytes non-compatible with the AB0-system A1 and B were combined with the B (alpha) and A (beta) test sera, and the weakest--when erythrocytes compatible with the AB0 test sera diluted with an equal volume of saline and heated at 70 degree C for 10 minutes.

ABO Blood-Group System↗
PubMed1984

Antibodies and thermolabile opsonins in the phagocytosis of human red and white blood cells pretreated with formaldehyde.

Erythrophagocytosis is conditioned by serum immunoglobulins. The extent of phagocytosis depends on the haematocrit of the red cell suspension pretreated with formaldehyde. The higher the haematocrit value, the lower will be the extent of phagocytosis. Phagocytosis of white blood cells pretreated with formaldehyde by granulocytes and monocytes is conditioned mainly by a thermolabile fraction of the serum, probably the complement.

Blood Physiological Phenomena↗