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PubMed1988

Genetic characterization of hyperresistance to formaldehyde and 4-nitroquinoline-N-oxide in the yeast Saccharomyces cerevisiae.

The hyperresistance to 4-nitroquinoline-N-oxide (4-NQO) and formaldehyde (FA) of yeast strains transformed with the multi-copy plasmids pAR172 and pAR184, respectively, is due to the two genes, SNQ and SFA, which are present on these plasmids. Restriction analysis revealed the maximal size of SFA as 2.7 kb and of SNQ as 2.2 kb, including transcription control elements. The presence of the smallest 2.7 kb subclone carrying SFA increased hyperresistance to formaldehyde fivefold over that of the original pAR184 isolate. No such increase in hyperresistance to 4-NQO was seen with the smaller subclones of the pAR172 isolate. Disruption of the SFA gene led to a threefold increase in sensitivity to FA as compared with the wild type. Expression of gene SNQ introduced on a multi-copy vector into haploid yeast mutants rad2, rad3, and snm1 did not complement these mutations that block excision repair.

4-Nitroquinoline-1-oxide↗
PubMed1985

Absence of mutagenicity in the urine of autopsy service workers exposed to formaldehyde: factors influencing mutagenicity testing of urine.

Hospital autopsy service workers and a matched control group were studied using a battery of genetic monitoring tests performed on samples of blood, semen and urine. The results of the analysis of urine for mutagens are described in this report. The participants in the study were matched with the controls for sex, age and their use of alcohol, tobacco and marijuana. Information was collected on general health, usage of medications and any exposure which might affect the outcome of the study. Individuals were sampled three times at approximately two month intervals. Time weighed average exposures to formaldehyde in the work areas were estimated at 0.61 to 1.32 ppm. Additionally, studies were carried out which examined various parameters affecting the testing of human urine samples for mutagenicity. No increase in mutagenicity was seen in the autopsy workers as compared to the control group. One individual who was receiving metronidazole and one control who smoked two packs of cigarettes per day had significantly mutagenic urine. A large proportion of the exposed individuals had toxic urine while only two of the control individuals had similar toxic urine. The material responsible for the toxicity has been isolated and purified but does not appear to be related to the formaldehyde exposure. Studies on the parameters affecting mutagenicity testing of urine with Salmonella typhimurium suggest that in the plate incorporation assay, TA100, but not TA98, can be affected by exogenous histidine. Furthermore, with the conditions employed in this study, 3 to 4% of labeled histidine added to urine samples was retained by the XAD-2 and subsequently eluted in the urine concentrate. Urinary histidine levels of unconcentrated samples ranged from 112 to 2614 nmol per ml (mean 994 nmol per ml) and the amount of histidine present correlated with the corresponding increases in histidine revertants with strain TA100.

Adult↗
PubMed1975

Formaldehyde-ozone-induced fluorescence and ACTH immunoreactivity in basophil tumours of the pituitary.

The ACTH cells of human foetal pituitary displayed intense formaldehyde-ozone-induced fluorescence characteristic of peptides or proteins with NH2-terminal tryptophan. Fourteen pituitary tumours were examined histochemically. Of these, two displayed formaldehyde-ozone-induced fluorescence. These two tumours were the only ones to exhibit ACTH immunoreactivity.

Adrenocorticotropic Hormone↗
PubMed1975

Formaldehyde-ozone-induced fluorescence in gastrin-producing tumours.

Material from eight peptide hormone-secreting tumours, extirpated from the pancreas or from the antrum-duodenum region, was examined. Four of the patients had the clinical manifestations of the Zollinger-Ellison syndrome, two showed the features of an insulin-secreting tumour and one had a glucagonoma. Gastrin-producing cells, identified by immunohistochemistry, were found in five of the tumours. These cells displayed a varying degree of formaldehyde-ozone-induced fluorescence. This agrees with previous observations on the gastrin cell of human antral and duodenal mucosa. From model experiments, formaldehyde-ozone-induced fluorescence is thought to reflect the presence of peptides having tryptophan in the NH2-terminal position. The nature of this peptide in gastrin-producing cells is unknown.

Adult↗
PubMed1976

[An improved histofluorescence procedure for freeze-dried paraffin-embedded tissue based on combined formaldehyde-glyoxylic acid perfusion with high magnesium content and acid pH].

A technique is described for highly sensitive and precise visualization of central catecholamine systems in paraffin sections of freeze-dried tissue. The procedure is based on perfusion of the animal with a solution containing formaldehyde and/or glyoxylic acid, in the presence of a very high magnesium content (40 g MgSO4/150 ml solution) and acid pH. The perfused tissue is rapidly frozen, freeze-dried, treated with formaldehyde vapours (at +80 degrees C for 1 h), embedded in parffin in vacuo, and finally sectioned. The present technique has a sensitivity for the dopamine- and noradrenaline-containing systems that is comparable with that of the glyoxylic acid-Vibratome technique, which utilizes fresh, glyoxylic acid-perfused tissue. Thus, the preterminal axon pathways become fluorescent throughout their full extent and the several new terminal systems, discovered with the glyoxylic acid-Vibratome method, are well demonstrable. The method is also highly useful for the study of the cell bodies and their dendritic processes. The catacholamine fibre systems are visualized without any signs of diffusion and with a richness in detail. In animals pretreated with L-tryptophan and MAO-inhibitor the technique is also useful for studies on central indolamine-containing systems.

Animals↗
PubMed1975

Formaldehyde-ozone-induced fluorescence in isolated gastrin granules.

In several mammals the antral gastrin cells display characteristic formaldehyde-ozone-induced fluorescence (375/500-520 nm). Such fluorescence is also given by gastrinoma cells. Gastrin granules, isolated from gastrinomas and identified by immunofluorescence and electron microscopy, were found to show intense formaldehyde-ozone-induced fluorescence.

Adult↗
PubMed1976

Glycine and alanine synthesis from formaldehyde and hydroxylamine in the field of ultrasound waves.

High intensity ultrasound waves coupled with other form of energy obviously were initiators of pre-biochemical reactions; these reactions occurred in the water masses of the primordial Earth. Essential biological substances like formaldehyde, ammonia, hydrocyanic acid, and amino acids compounds similar to carbohydrates by their properties were synthesized in the field of ultrasound waves in model experiments. The main partners of these reactions are water and gases of reductional atomosphere: hydrogen, carbon monoxide, methane, nitrogen and argon. Formation of amino acids takes place in aqueous solutions of formaldehyde and hydroxylamine. The sonication yielded alanine and glycine, 2.0 X 10(-7) and 1.8 X 10(-7) molecules per 100 eV respectively.

Alanine↗
PubMed1981

Recent developments in aldehyde-induced monoamine fluorescence: the aluminum-formaldehyde (ALFA) method applied to immature and adult central nervous tissue.

In this review, the new aluminum-formaldehyde (ALFA) histofluorescence method for the highly sensitive visualization of monoamine-containing neurones in adult and immature central nervous tissue is summarized. Animals are first perfused with a buffer containing high concentrations of aluminum ions and the brains are then freeze-dried, reacted with formaldehyde vapour and further processed according to the Falck-Hillarp fluorescence method. The ALFA technique applied to adult brains visualizes all known catecholamine neurone systems with a sensitivity comparable to, and for certain noradrenergic systems higher than, that of the previously published glyoxylic acid-Vibratome method. The catecholamine systems in immature brains are demonstrated with a sensitivity clearly superior to that of any other available method. If the ALFA method is combined with systemic injections of alpha-methylnoradrenaline into young animals (less than one week old), there is a dramatic increase in the intensity and number of catecholaminergic fibres. Many catecholaminergic systems which have too low concentrations of transmitter to be visualized in the untreated animal even with the ALFA method, can be demonstrated after administration of alpha-methylnoradrenaline. The use of freeze-dried, paraffin-embedded tissue in the ALFA method makes possible convenient storage and parallel processing of many specimens. This mode of processing also allows en bloc reaction, which is the only way by which consistent and reproducible fluorescence yields can be obtained throughout large series of sections and parallel-processed specimens. In animals pretreated with L-tryptophan and monoamine oxidase-inhibitor, the technique is also useful for studies on central indolamine-containing systems.

Age Factors↗
PubMed1979

Differentiation of the formaldehyde-induced fluorescent products of noradrenaline and dopamine by microspectrofluorometry.

The influence of concentration of dopamine and noradrenaline on the spectral characteristics of their formaldehyde-induced fluorophore, together with the influence of duration of reaction with formaldehyde, has been investigated in a model system. No substantial differences between fluorescence spectra of the amine fluorophores were observed. Accordingly, the influence of hydrochloric acid and ammonia vapours on the fluorophores was investigated. A shift to shorter wavelengths in the excitation maximum of each fluorophore was observed after a brief exposure to hydrochloric acid vapour; more prolonged exposure resulted in a pronounced shift back to longer wavelengths in the case of noradrenaline but no substantial change was observed with dopamine. Brief exposure to hydrochloric acid vapour resulted in a substantial increase in the rate of fading of the noradrenaline fluorophore on exposure to exciting radiation. It is suggested that this offers a convenient way of differentiating the amines.

Dopamine↗
PubMed1980

Factors influencing the fluorescence spectra of the formaldehyde-induced reaction product of 5-hydroxytryptamine.

Fluorescence excitation and emission spectra of the formaldehyde-induced fluorophore of 5-hydroxytryptamine in a Sephadex model have been examined following exposure to hydrochloric acid or ammonia vapour. Exposure to hydrochloric acid vapour produced excitation spectra with broad maxima centred around 400 nm, whilst exposure to ammonia vapour intensified the maximum normally seen at approximately 450 nm relative to that seen at 400 nm. The emission maximum was generally broad and poorly defined following exposure to hydrochloric acid vapour; exposure to ammonia vapour had little effect on its location. Exposure of the formaldehyde-induced fluorophore in models containing 5-hydroxytryptamine to 300 nm irradiation caused a substantial shift in the position of the emission maximum; a concomitant increase in the fluorescence intensity was also observed. When the fluorescence present in duodenal enterochromaffin cells was examined after similar treatment, a number of differences in the response of the fluorophore were noted.

Ammonia↗
PubMed1979

Formaldehyde-fluorescamine-induced fluorescence of mammary carcinoma cells. Lack of concordance with occurrence of oestrogen-binding receptor proteins.

The combined formaldehyde-fluorescamine technique demonstrates fluorescence by mammary carcinoma cells whereas cells of the normal gland or of benign tumours do not show fluorescence. We have studied the correlation between histological staging of the disease, concentrations of oestrogen-binding proteins and the occurrence of formaldehyde-fluorescamine (FF)-inducible fluorescence. Our results demonstrate that the FF-technique detects all types of mammary carcinoma cells irrespective of their concentration of oestrogen receptors. Hence, the FF-technique represents a valuable tool for detecting both hormone-responsive and hormone-unresponsive malignant cells of the mammary gland.

Breast Neoplasms↗
PubMed2003

Chemiluminescence determination of melatonin and some of its derivatives using potassium permanganate and formaldehyde system.

It was found that melatonin and its derivatives, such as N-acetyl- 5-methoxytryptamine (MT), N-acetyl-5-hydroxytryptamine (NAS), 5-Methoxytrypt- amine (5-MT), 5-Methoxyindolyl acetic acid (5-MIAA) and N-acetyl-5-methoxy- 6-hydroxytryptamine (6-HMT) would give chemiluminescence in the acidic potassium permanganate solution, and formaldehyde would enhance this chemiluminescent reaction greatly. The optimum conditions for this chemiluminescent reaction were studied in detail by a flow injection system. A new simple rapid method has been developed under the optimum conditions for determination of melatonin. This method has the advantages of high sensitivity, wide range of linear response and low detection limit. On the basis of investigation of chemiluminescent, fluorescent and UV spectra of melatonin in acidic solution containing potassium permanganate and formaldehyde, a possible mechanism of this reaction was proposed.

Flow Injection Analysis↗
PubMed2005

Flow injection chemiluminescence determination of naftopidil based on potassium permanganate oxidation in the presence of formaldehyde or formic acid.

A flow injection method is proposed for the determination of naftopidil based upon the oxidation by potassium permanganate in a sulfuric acid medium and sensitized by formaldehyde and formic acid. The optimum chemical conditions for the chemiluminescence emission were 0.25 mM potassium permanganate and 4.0 M sulfuric acid. Two manifolds were tested and instrumental parameters such as the length of the reactor, injection volume and flow rate were compared. When using the selected manifold in the presence of 0.4 M formaldehyde, naftopidil gives a second-order calibration graph over the concentration range 0.1-40.0 mg L(-1) with a detection limit calculated (as proposed by IUPAC) of 92.5 ng mL(-1) and a standard deviation of 0.12 mg mL(-1) for ten samples of 10.0 mg L(-1) naftopidil. In the presence of 1.15 M formic acid, naftopidil gives a second-order calibration graph over the concentration range 0.05-40.0 mg L(-1) with a detection limit of 14.2 ng mL(-1) and a standard deviation of 0.37 mg mL(-1) for ten samples of 10.0 mg L(-1) naftopidil. In both cases, the determination is free from interferences from common excipients such as sucrose, glucose, lactose, starch and citric acid.

Antihypertensive Agents↗
PubMed2001

Ambient formaldehyde detection with a laser spectrometer based on difference-frequency generation in PPLN.

A laser spectrometer based on difference-frequency generation in periodically poled LiNbO3 (PPLN) has been used to quantify atmospheric formaldehyde with a detection limit of 0.32 parts per billion in a given volume (ppbV) using specifically developed data-processing techniques. With state-of-the-art fiber-coupled diode-laser pump sources at 1083 nm and 1561 nm, difference-frequency radiation has been generated in the 3.53-micrometers (2832-cm-1) spectral region. Formaldehyde in ambient air in the 1- to 10-ppb V range has been detected continuously for nine and five days at two separate field sites in the Greater Houston area operated by the Texas Natural Resource Conservation Commission (TNRCC) and the Houston Regional Monitoring Corporation (HRM). The acquired spectroscopic data are compared with results obtained by a well-established wet-chemical o-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine (PFBHA) technique.

Atmosphere↗
PubMed2000

The efficacy and side effects of gelatin-resorcinol formaldehyde-glutaraldehyde (GRFG) glue for preventing and sealing pulmonary air leakage.

This study was conducted to examine the efficacy and side effects of gelatin-resorcinol formaldehyde-glutaraldehyde (GRFG) glue, when used for preventing or sealing pulmonary air leakage during lung surgery. Formaldehyde-glutaraldehyde (FG) jelly was prepared by mixing FG fluid with 2.5% carboxymethyl cellulose to increase its viscosity. A GRFG glue-spreading stapler was employed to prevent air leakage from the staple line when cutting emphysematous lung tissue in 26 patients, 25 of whom underwent video-assisted thoracoscopic surgery (VATS) and 1, open thoracotomy. A glue-sealing procedure was employed to stop existing pulmonary air leakage in a further 36 patients, 28 of whom underwent VATS and 8, open thoracotomy. The glue-spreading stapler technique prevented air leakage in all 26 patients (100%), while the glue-sealing procedure for pulmonary air leakage stopped air leakage in 31 of the 36 patients (86%). Two patients who underwent glue sealing for air leakage from a deeply cut lung surface suffered massive pulmonary air leakage on postoperative day (POD) 1 and 6, respectively, and required repeat surgery to suture the lung fistula. A transient fever of 38 degrees-39 degrees developed on POD 7 in 6 of the 62 patients (9.7%), but no other complications were observed. These results demonstrated that GRFG is safe and effective in preventing or stopping pulmonary air leakage in the peripheral lung, but not for stopping air leakage from a deeply cut lung.

Adult↗
PubMed2006

Vitamin E protects against oxidative damage caused by formaldehyde in the liver and plasma of rats.

It is well known that formaldehyde (FA) and reactive oxygen species (ROS) are cytotoxic and potentially carcinogenic. Although the individual effects of these reactants on cells have been investigated, the cytotoxicity exerted by the coexistence of FA and ROS is poorly understood. The present study was carried out to evaluate oxidant/antioxidant status and biochemical changes occurring after chronic formaldehyde toxicity in liver tissue and plasma of rats and protective effect of vitamin E (vit E) against oxidative damage. Eighteen rats were divided into three groups: (1) control rats, (2) rats treated with FA (FAt), and (3) rats treated with FA plus vit E (FAt + vit E) groups. After the treatment, the animals were sacrificed and liver tissues were removed for biochemical investigations. As a result, FA treatment significantly increased the levels of tissue malondialdehyde (MDA), protein carbonyl (PC), nitric oxide (NO) and the activity of xanthine oxidase enzyme (XO). On the other hand, FA exposure led to decrease in superoxide dismutase (SOD) and catalase (CAT) activities in liver tissues compared to control. FA caused significant decreases in total protein (TP) and albumin (ALB) whereas increases in aspartate transaminase (AST), alanine aminotransferase (AST), alkaline phosphatase (ALP) and interleukine-2 (IL-2) levels in plasma. Vit E treatment abolished these changes at a level similar to the control group. It was concluded that vit E treatment might be beneficial in preventing FA-induced liver tissue damage, and therefore have potential for clinical use.

Animals↗
PubMed1983

Presence of formaldehyde in biological media and organic solvents: artifactual formation of tetrahydro-beta-carbolines.

A gas chromatography-mass spectrometry method is described for the identification and quantitation of 6-hydroxy-1,2,3,4-tetrahydro-beta-carboline (6OHTHBC). During the analysis of 6OHTHBC in human platelets, the artifactual formation of 6OHTHBC was observed and shown to be due to the presence of formaldehyde in both organic solvents and in platelet homogenates. Formaldehyde was facilely removed from the organic solvent via a Pictet-Spengler reaction; however, removal from tissue homogenates was not possible by using conventional aldehyde-trapping agents. The solution of these problems and their consequences for persons attempting to establish the in vivo presence of tetrahydro-beta-carbolines or biochemically study tissue preparations are discussed.

Blood Platelets↗