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PubMed2003

Carcass, sensory, and adipose tissue traits of Brangus steers fed casein-formaldehyde-protected starch and/or canola lipid.

We predicted that providing rumen-protected starch to the small intestine would increase adiposity of intramuscular adipose tissue, and hence marbling scores. Eighteen 15-mo-old Brangus steers were assigned randomly to one of three dietary treatment groups: 1) cracked corn (Corn); 2) casein-formaldehyde-protected lipid (Canola Lipid); or 3) casein-formaldehyde-protected starch (Marble Plus). All diets were equally balanced for ME (2.91 Mcal/kg), CP (12.5%), and DM (89%). Ether extract was 3.7, 6.9, and 6.9% for the Corn, Canola Lipid, and Marble Plus diets, respectively, and the Marble Plus also contained 3.7% protected starch. Steers were fed the diets for 126 d before slaughter. Average daily feed intake (as-fed basis), ADG, and feed:gain ratio (P > or = 0.23) did not differ among treatments. Carcasses across treatments did not differ (P = 0.26) in adjusted fat thickness, longissimus muscle area, hot carcass weight, dressing percentage, marbling scores, or USDA quality grade. Percentage of kidney, pelvic, and heart fat was higher (P < 0.01) and USDA yield grade tended (P = 0.08) to be higher, for carcasses from Canola Lipid- and Marble Plus-fed steers than for carcasses from Corn-fed steers. Of the descriptive meat sensory attributes, connective tissue amount (P = 0.06) and painty flavor (P = 0.12) tended to be greater in meat from Marble Plus steers than from Canola Lipid steers. Percentages of 18:2n-6 and 18:3n-3 were higher (P < 0.01), and 15:0, 16:0, and 17:0 were lower (P < or = 0.07) in tissues from Canola Lipid- and Marble Plus-fed steers than in Corn-fed steers. Mean adipocyte volume was greater (P = 0.02) in i.m. adipose tissue and tended (P = 0.11) to be greater in s.c. adipose tissue of Canola Lipid steers (848 pL) vs. Corn steers (536 pL). Glucose incorporation into total lipids, glyceride-glycerol, and fatty acid fractions was highest (P < 0.01) in s.c. adipose tissue from steers fed Marble Plus but was unaffected (P > or = 0.33) by diet in i.m. adipose tissue. Fatty acid synthetase activity tended (P = 0.08) to be higher in s.c. adipose tissue of Marble Plus steers, and NADP-malic dehydrogenase activity was higher (P = 0.03) in i.m. adipose tissue of Canola Lipid steers. We conclude that Marble Plus did not improve carcass quality, but also did not reduce beef sensory attributes. Any differences we observed in carcass characteristics, adipose tissue cellularity, or lipogenesis apparently were caused by the protected lipid rather than the protected starch.

Adipose Tissue↗
PubMed1976

Neutralizing activity in the gastrointestinal contents of piglets vaccinated with a live or formaldehyde-inactivated porcine enterovirus.

Neutralizing activity against porcine enterovirus strain T80 was demonstrated in the gastrointestinal contents of piglets given live T80 virus orally or parenterally, but little or no neutralizing activity was detected in the gastrointestinal contents of piglets given formaldehyde-inactivated virus by either route. The gastrointestinal neutralizing response was first detected 14 days after oral dosing, coincidentally with a fall in the titre and distribution of virus. The neutralizing response was highest at 23 days, and dropped markedly by 36 days, whereas no response was detected until 36 days in piglets which received live virus by the intramuscular route. Virus generally appeared earlier, was more widely distributed, and reached higher titres in the gastrointestinal tract of piglets which received live virus orally than in those which received the same preparation by the intramuscular route. The highest serum neutralizing response occurred in the piglets given live virus orally. The serum response in the piglets which received live virus intramuscularly appeared earlier and was biphasic. The serum response in the piglets receiving formaldehyde-inactivated virus appeared as early as the response to live virus given by the same route, but remained relatively low throughout the period of observation.

Administration, Oral↗
PubMed1990

Analysis of antigen receptor gene rearrangements in ethanol and formaldehyde-fixed, paraffin-embedded specimens.

Molecular hybridization analysis of DNA prepared from frozen specimens obtained from patients with lymphoproliferative disorders has aided in the determination of the lineage and clonality of the neoplastic cells in many cases. We investigated whether high molecular weight DNA suitable for nucleic acid hybridization studies could also be prepared from fixed, paraffin-embedded material. After selecting nine representative cases, we extracted DNA from frozen sections by using standard methods, and from ethanol-fixed tissue in paraffin blocks. The yields of DNA from ethanol-fixed blocks were similar to yields from frozen tissue. DNA from frozen and ethanol-fixed tissues was subjected to Southern blot hybridization and probed for rearrangements of immunoglobulin heavy, and kappa, and lambda light chain genes, as well as for the T cell receptor beta-chain gene. In each of the cases, comparable results were obtained, regardless of the source of DNA. DNA extracted from ethanol-fixed blocks stored for 2 years gave identical results. We also prepared DNA from formaldehyde-fixed, paraffin-embedded tissue obtained from six of the patients. Five of the specimens yielded spoolable DNA (average recovered, 313 micrograms), but the DNA was degraded more than that obtained from the frozen or ethanol-fixed specimens. Formaldehyde-treated DNA gave variable results in Southern blot hybridization studies, and less than half of the results were interpretable. We conclude that ethanol-fixed, paraffin-embedded tissues provide an excellent source of DNA for nucleic-acid hybridization studies, and that they are easily handled and stored.

DNA↗
PubMed1989

Bovine liver formaldehyde dehydrogenase. Kinetic and molecular properties.

The dimeric formaldehyde dehydrogenase from bovine liver has been resolved into three nearly homogeneous enzyme forms by the successive use of ion-exchange, affinity, and ampholine (chromatofocusing) chromatography. The different enzyme species were isolated in the approximate proportions 3:2:1, having pI values of 6.5, 6.2, and 6.0, respectively. The subunit molecular weights of the three forms are all similar (Mr congruent to 41,000), on the basis of sodium dodecyl sulfategel electrophoresis. The enzyme species appear to arise from covalent differences unrelated either to partial proteolysis during isolation or to differential sialization of homodimeric protein. Human liver contains a single major form and two minor forms of formaldehyde dehydrogenase having pI values very similar to those found for the bovine liver enzyme. The macroscopic kinetic constants (V, V/K) for the three forms of the dehydrogenase from bovine liver are all similar in magnitude, using NADH and S-hydroxymethylglutathione as substrates. The isotope-sensitive hydride transfer step is not significantly rate-limiting during catalysis by any of the forms, as evidenced by the near-unity primary deuterium isotope effects on both V and V/KS (for S-hydroxymethylglutathione); catalysis may be limited by the rate of dissociation of at least one (and possibly both) of the product molecules. In support of rate-limiting dissociation of NAD+ in the normal reaction, V increases by approximately 22-fold and isotope effects of approximately 1.4 are observed on both V and V/KS, using the coenzyme analog 3-acetylpyridine adenine dinucleotide. Product dissociation from the active site appears to be accelerated by the presence of dilute denaturing agents, perhaps indicative of a rate-limiting conformational transition associated with product release.

Aldehyde Oxidoreductases↗
PubMedDate not supplied

[Length of nucleosomal DNA repeat in whole cells, fixed by freezing in the presence of formaldehyde].

It is shown that whole cells can be effectively fixed in the presence of formaldehyde at -12 degrees C. This reaction is used for the study of the native structure of chromatin. In the nuclei isolated from fixed cells the chromatin has the nucleosomal structure. The size of nucleosomal DNA in these nuclei estimated by hydrolysis with staphylococcal nuclease does not differ significantly from repeat length in the nuclei fixed after isolation or in non-fixed nuclei. However it is shown that mono- and oligonucleosomes in the nuclei from fixed whole cells are significantly more stable to the exonucleolytic degradation than in either nuclei fixed after isolation or non-fixed nuclei. The results suggest that the nuclei isolation does not appreciably affect the chromatin structure. The fixation of whole cells by formaldehyde in frozen suspension can be used also to study the structure of other cellular components and macromolecular complexes directly in the whole cell.

Animals↗
PubMed1993

Characterization of a novel tungsten-containing formaldehyde ferredoxin oxidoreductase from the hyperthermophilic archaeon, Thermococcus litoralis. A role for tungsten in peptide catabolism.

Thermococcus litoralis is a strictly anaerobic archaeon (archaebacterium) that grows at temperatures up to 98 degrees C by fermenting peptides. Its growth is stimulated by tungsten, and a tungsten-containing iron-sulfur protein that has formaldehyde ferredoxin oxidoreductase (FOR) activity has been purified. FOR is a homotetramer with a subunit M(r) of 70,000. It contains approximately four irons, four acid-labile sulfides, and one tungsten atom per subunit. The tungsten appears to be present as a pterin cofactor, and the Fe/S seems to comprise an unusual [4Fe-4S] cluster that in the reduced state exists in a pH-independent S = 3/2 form and a pH-dependent S = 1/2 form. FOR catalyzed the oxidation of C1-C3 aldehydes with a temperature optimum > or = 90 degrees C and used T. litoralis ferredoxin as an electron acceptor. It did not oxidize aldehyde phosphates, utilize CoASH, or reduce NAD(P). The N-terminal sequence of FOR shows homology with the tungsto-iron-sulfur aldehyde ferredoxin oxidoreductase previously purified from the saccharolytic, hyperthermophilic archaeon Pyrococcus furiosus, in which it is proposed to function in a novel pyroglycolytic pathway (Mukund, S., and Adams, M. W. W. (1991) J. Biol. Chem. 266, 14208-14216). We show here that P. furiosus, which will also grow on peptides, albeit poorly, contains a second aldehyde-oxidizing enzyme analogous to FOR. Similarly, T. litoralis, which utilizes saccharides if limited for peptides, contains low concentrations of an enzyme analogous to AOR. It is proposed that formaldehyde (apparent Km, 62 mM) is not the true substrate for FOR; rather, the enzyme has an as yet unknown role in peptide fermentation in hyperthermophilic archaea.

Aldehyde Oxidoreductases↗
PubMed1998

Detection of the SYT-SSX fusion transcripts in formaldehyde-fixed, paraffin-embedded tissue: a reverse transcription polymerase chain reaction amplification assay useful in the diagnosis of synovial sarcoma.

Identification of the t(X;18)(p11.2;q11.2) translocation and detection of the resulting SYT-SSX1 or SYT-SSX2 fusion transcripts are useful diagnostic markers for synovial sarcoma. In this study, we developed a polymerase chain reaction (PCR) assay to amplify SYT-SSX fusion transcripts. The primer sequences were designed to generate small PCR products and to amplify sequences of all known SSX genes as fusion partners for the SYT gene. RNA was obtained from formaldehyde-fixed and paraffin-embedded tissues of 22 immunohistochemically characterized synovial sarcomas, 6 of them cytogenetically confirmed as t(X;18) positive. The SYT-SSX fusion transcripts were detected in 21 of the 22 analyzed cases. The type of the fusion was identified by the specific restriction enzyme digestion pattern as SYT-SSX1 in 13 cases and SYT-SSX2 in 7 cases; in 1 case, the type could not be assigned. None of the cases showed involvement of the SSX3, SSX4, or SSX5 genes, the other members of the SSX gene family. In seven cases, the SYT-SSX1 or SYT-SSX2 fusion transcripts were demonstrated in frozen tissue using a different PCR assay. The PCR products were confirmed as SYT-SSX sequences by sequencing in five randomly selected cases. Fifteen other sarcomas and related tumors were negative for SYT-SSX fusion transcripts. The PCR assay used in this study performs well in formaldehyde-fixed and paraffin-embedded tissue, and it shows a high specificity. This assay can be used as an adjunct test for diagnostically difficult cases or in retrospective studies to refine the diagnosis of synovial sarcoma in archival material.

Adolescent↗
PubMed1998

Significance of formaldehyde-induced DNA-protein crosslinks for mutagenesis.

Formaldehyde (FA) is a genotoxic substance, induces tumors in the nasal epithelium of rats, and is suspected to be a human carcinogen. As a primary DNA lesion, FA induces DNA-protein crosslinks (DPC) and the formation of DPC has been used as a measure of exposure for risk estimation. However, the significance of DPC for mutagenesis and carcinogenesis is at present poorly understood. We therefore performed comparative investigations on the induction of DPC and other genetic endpoints by FA in V79 Chinese hamster cells. The amount of DPC was comparatively determined with the K-SDS assay and the comet assay. Both tests gave similar results but the comet assay was much foster and easier to perform. Our results show that FA significantly induces DPC, sister-chromatid exchanges, and micronuclei in the same range of concentrations, parallel to the induction of cytotoxicity (relative cloning efficiency). In contrast, treatment of V79 cells with FA did not induce gene mutations in the HPRT test even after variations of the treatment protocol. Our results indicate that FA-induced DPC seem to be related to cytotoxicity and clastogenicity but do not lead to the formation of gene mutations in mammalian cells. It is suggested that FA-induced DPC do not cause gene mutations that are involved in FA-induced carcinogenesis.

Animals↗
PubMed2000

HPLC-OPLC-MS investigation of change of formaldehyde and its generators in human teeth of different physiological stage.

Taking into consideration the unquestionable intracellular occurrence of formaldehyde (HCHO) and its generators in cells of plant, animal and human organisms as well as in body fluids it was resolved to determine their levels in hard tissues of physiologically and pathologically changed teeth. The aim of the work was to determine the relationship between the level of HCHO and the levels of its generators in pathologically changed teeth, mainly carietic teeth as tooth caries is still a serious and commonly occurring problem. The occurrence of HCHO (captured as its dimedone adduct) and some of its potential generators was demonstrated in the hard tissues of healthy and pathological human teeth by means of OPLC, HPLC and MS analyses. It was established that the measurable level of HCHO was increased in the carietic teeth in comparison with healthy ones. In the case of paradontic tooth sample, a dramatic increase of HCHO was observed and at the same time the level of betaines was decreased considerably. The obtained results give a new insight into the pathology of hard tissues of teeth in strong correlation with the phases of stress syndrome.

Betaine↗
PubMedDate not supplied

Formaldehyde activity on historical glass objects in museum microclimate.

Degradation of some cultural heritage monuments has been caused by interaction with the closest environment (micro-climate). Amount of separate compounds is very small and because of it, this fact becomes neglected. Time and temperature can induce their activity finally causing deterioration. In this category organic compounds can be interpreted as one of museum show - case element. This statement has been improved by testing glass objects and their suitable sensors (model glasses). Destructive activity of formaldehyde on historical glasses belonging to the XVIII-th c. objects with totally different compositions has been confirmed by carried out experiments. For historical material which is very limited, sensor glass method has been applied. Sensors are prepared on the base of results of chemical analyses of original glass chemical analyses and melted on laboratory scale (according to historical data). Induced corrosion for sensor supports knowledge about deterioration process in real micro-environmental conditions. The following testing methods were used: scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), optical interferometer (OI), inductively couple plasma (ICP).

Formaldehyde↗
PubMed1989

Building-related illness and antibodies to albumin conjugates of formaldehyde, toluene diisocyanate, and trimellitic anhydride.

A case of building-related health complaints was investigated with respect to the relationship among frequency of symptoms, antibodies to albumin conjugates of formaldehyde (HCHO), toluene diisocyanate (TDI), and tirmellitic anhydride (TMA), and volatile organic chemicals (VOCs). The indoor air concentrations of VOCs, HCHO, TDI, and TMA did not exceed Fed-OSHA and ACGIH permissible standards. However, HCHO concentrations ranged between 0.05 and 0.08 ppm. The reported symptoms were multiple, involving the eyes, nose, sinuses, throat, lungs, skeletomuscular system, and central nervous system. Anti-HCHO, -TDI, and -TMA isotypes were found in 12 of 14 full-time employees and were nondetectable in one part-time employee. There was a positive, but not statistically significant, correlation (r values ranged between .24 and .55) between symptoms and the geometric mean titers to conjugates. The data suggest that a synergistic immunological response to airborne chemicals may be occurring in these subjects. In conclusion, immunological monitoring of affected individuals where chemicals are suspected may prove to be useful in future investigations of building-related illness.

Adult↗
PubMed2005

Methanol, formaldehyde, and sodium formate exposure in rat and mouse conceptuses: a potential role of the visceral yolk sac in embryotoxicity.

BACKGROUND: Methanol (CH3OH) is believed to be teratogenic based on rodent studies. The mouse is more sensitive than the rat, but mechanisms of toxicity and identification of teratogenic metabolites are uncertain. METHODS: Rat and mouse whole embryo cultures are used to distinguish toxicity of CH3OH and its metabolites, formaldehyde (HCHO) and formate (HCOONa), which are produced following transit through the visceral yolk sac (VYS), via addition to culture medium, or by direct embryonic exposure through microinjection into the amnion. RESULTS: Embryonic viability, increased dysmorphogenesis, and decreased growth parameters were altered in a dose-dependent fashion for each compound. Mouse embryos were more sensitive than rat, as indicated by significant decreases in viability at comparable, lower concentrations. HCHO produced dysmorphogenesis and caused embryolethality at nearly 1000-fold lower concentrations (0.004 mg/ml) than seen with either CH3OH or HCOONa. All agents produced incomplete axial rotation and delayed neural tube closure in mice, but only CH3OH elicited similar effects in the rat. Increased growth retardation, blood pooling in the head and VYS, enlarged pericardium, accumulation of necrotic matter in the amnion, and hypoplastic prosencephalon were observed in both species with all compounds. Microinjection of compounds into the amnion produced higher mortality in mouse and rat, compared to equimolar amounts added to the culture medium. CH3OH did not prevent neural tube closure in the rat when microinjected. CONCLUSIONS: HCHO is the most embryotoxic CH3OH metabolite and elicits the entire spectrum of lesions produced by CH3OH. The VYS serves a general protective role against toxicity and inherent differences in the embryonic metabolism of CH3OH may determine species sensitivity.

Animals↗
PubMedDate not supplied

Flow injection-chemiluminescence determination of amoxycillin using potassium permanganate and formaldehyde system.

It was found that amoxycillin can react with potassium permanganate in an acidic medium to produce chemiluminescence, which is greatly enhanced by formaldehyde. The optimum conditions for this chemiluminescent reaction were studied in detail using a flow-injection system. The experimental results indicate that, under optimum conditions, the chemiluminescence intensity is linearly related to the concentration of amoxycillin in the range 5.48 x 10(-8)-2.74 x 10(-6) mol/L, with a detection limit (3sigma) of 4.1 x 10(-8) mol/L. The relative standard deviation was 1.0% at 1.1 x 10(-6) mol/L amoxycillin (n = 11 measurements). This method has the advantages of high sensitivity, fast response and ease of operation. The method was successfully applied to the determination of amoxycillin in raw medicines and capsules.

Amoxicillin↗
PubMed1975

The effect of methanol, formaldehyde, and formic acid on growth of Candida boidinii 11 Bh.

The dependence of the specific growth rate of Candida boidinii 11 Bh on methanol concentration follows Monod-type kinetics only in a narrow concentration range (0--0.8 v/v), with a saturation constant of about 19 mmol. With a further increase in methanol concentration of up to 3% v/v, the specific growth rate remains constant. Beyond this level, the growth rate gradually drops to zero, reaching the threshold value at 7.8% v/v. The specific growth rate is also strongly dependent on the size of the inoculum. The biomass yield decreases with an increase in the methanol concentration. Formaldehyde and formic acid, oxidative products of methanol, approximately 100 and ten times, respectively, more toxic to growth than the original substrate.

Candida↗
PubMed2002

Detection of oxidative stress. Interest of GC-MS for malondialdehyde and formaldehyde monitoring.

Ischemia-reperfusion syndrome is a condition where the role of oxygen free radicals is important. Malondialdehyde (MDA) and formaldehyde (FA), products of lipid peroxidation, are the presumptive markers for the development of oxidative stress in tissues and plasmas. A GC-MS method for the determination of MDA and FA in rat brain extract is described. Rat brains were homogenized with deionized water. The homogenates were derivatized with 2,4-dinitrophenylhydrazone (DNPH) to obtain hydrazines derivatives of MDA and FA. The hydrazine derivatives were analyzed by GC-MS and quantitation was by single ion monitoring (SIM). The retention times of FA and MDA were, respectively, 13.75 and 14.20 min, and for SIM quantitation, ion at m/z 210 for FA, and m/z 158 for MDA were used. The results showed that it is possible to estimate the products of lipid peroxidation in brain and to monitor the oxidative stress developed during the ischemia-reperfusion syndrome compared to the normal values.

Animals↗
PubMed2004

Quantitation of normal and formaldehyde-modified deoxynucleosides by high-performance liquid chromatography/UV detection.

A sensitive and selective method was developed for the first time to quantify simultaneously the normal and formaldehyde (FA)-modified bases in human placental DNA treated with 100 ppm FA for 20 h at 37 degrees Celsius. Digestion of DNA to deoxynucleosides with DNase I, phosphodiesterase and alkaline phosphatase occurred in that order with centrifugation steps. The normal and FA-modified deoxynucleosides were then resolved from one another and reagent blank interferences to produce selective separation through high performance liquid chromatography-ultraviolet detection at 254 nm. A C(18) reversed-phase column facilitated the resolution using 5 mm ammonium acetate and a gradient of 0-6% methanol at fl ow rates of 0.3-1.4 mL/min before column cleaning. The lower quantifiable limits for deoxyadenosine, deoxyguanosine, deoxycytidine, thymidine, N(6)-hydroxymethyldeoxyadenosine (N(6)-dA), N(2)-hydroxymethyldeoxyguanosine (N(2)-dG) and N(4)-hydroxymethyldeoxycytidine (N(4)-dC) were 11, 7.6, 12, 15, 10, 10 and 22 pmol, respectively. The abundance order of the modified deoxynucleosides was N(6)-dA > N(2)-dG > N(4)-dC. dT did not form hydroxymethyl derivatives. The respective concentrations were about 6.0, 10.0 and 23 pmol of modified deoxynucleosides in 80 micro g of human placental DNA after treatment with 100 micro g/mL of formalin for 20 h at 37 degrees Celsius. The stabilities of N(6)-dA and N(2)-dG were much better at -20 degrees Celsius than at 25 degrees Celsius, where the respective halftimes were about 50.1 and 21.0 h.

Chromatography, High Pressure Liquid↗
PubMed1975

Identification of alkaloids; the condensation products of biogenic amines with formaldehyde, enzymatically formed from 5-methyltetrahydrofolic acid.

The use of thin-layer chromatography has demonstrated that incubations of indoleamines with 5-methyl[14-C]tetrahydrofolic acid and an enzyme previously described as an N-methyltransferase, do not yield Nw, N1, or O-methylated products. Further elucidation by thin-layer chromatography, gas chromatography, mass spectrometry and selected ion monitoring enabled us to identify the reaction products as tetrahydroisoquinolines and tetrahydro-beta-carbolines in mixtures incubated respectively with catecholamines and indoleamines in the presence of 5-methyl[14-C]tetrahydrofolic acid and enzyme. The alkaloids have been shown to originate from a spontaneous condensation of the corresponding amines with formaldehyde, this latter being formed in the first stage of the reaction by enzymatic conversion from 5-methyltetrahydrofolic acid.

Alkaloids↗
PubMed1991

Kinky microtubules: bending and breaking induced by fixation in vitro with glutaraldehyde and formaldehyde.

We have employed video-enhanced light microscopy to study alterations of the overall shape of microtubules that are produced by the aldehyde fixation methods commonly employed to study them in vitro. Changes brought about by these methods include deformation and breakage. The severity of the effects depends on the fixative employed and increases with its concentration, and with the time of fixation. The changes are observed under a variety of conditions, such as brief exposure to 3.7% formaldehyde, or somewhat longer exposure to glutaraldehyde at concentrations as low as 0.05%. The observed distortion explains why microtubules usually appear curved or sinuous in electron micrographs while appearing relatively rigid and linear in video-enhanced light microscopy. The observed breakage implies that caution must be used in inferring length distributions from measurements of aldehyde-fixed microtubules.

Animals↗