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PubMed2003

Immunoglobulin gene rearrangement investigations in the diagnosis of lymphoid malignancies from formaldehyde-fixed biopsies.

Determination of the biologic potential of lymphoid proliferations in biopsies can be difficult by standard histological or even immunohistochemical examination. Polymerase chain reaction (PCR) has been used with increasing frequency to detect clonal rearrangements of the immunoglobulin heavy chain (IgH) in formaldehyde fixed, paraffin wax embedded tissues. Sensitivity ranges between 50 and 80%, and therefore at least 20% of neoplasms remain undetected by these approaches. Few investigators have attempted to detect immunoglobulin light chain (IgL) gene rearrangements by PCR using paraffin wax embedded samples. We studied 29 cases of B-cell neoplasms, along with 21 cases with equivocal histology and 4 reactive biopsies, using degenerate oligoprimers to amplify Ig(kappa) and Ig(lambda) light chain genes, along with IgH (Fr 1, 2 and 3) gene rearrangement analysis. The combination of these methods detected clonality in 93% of cases (27/29) with histological diagnosis of B-NHL. Fr2 and Fr3 primers detected clonality in 79% (23/29) of cases. IgL chain rearrangements detected 4 cases (14%), negative for IgH rearrangements, improving sensitivity from 79 to 93%. Clonality was detected in 52% (11/21) of histologically equivocal lymphoid proliferations, including one case detected by IgL rearrangements which was negative for IgH rearrangements. Archival material from 4 cases with reactive histology produced polyclonal results. These results confirm that PCR based immunoglobulin gene rearrangement is a sensitive and specific method for demonstrating B-cell clonality in paraffin-wax embedded sections. The addition of IgL analysis to the IgH assay allows the detection of greater than 90% of B-cell lymphoproliferative disorders from routine histological specimens with poor preservation of genomic DNA.

Biopsy↗
PubMed1985

Effect of subchronic formaldehyde inhalation on minute volume and nasal deposition in Sprague-Dawley rats.

Since respiratory depression during formaldehyde (HCHO) inhalation is an important mechanism in reducing the dose received and potentially the toxicity in the nasal passages of exposed animals, this study was conducted to determine if changes in the pattern of minute volume response and nasal deposition occurred in nosepiece challenges to rats after long-term repeated exposures to HCHO. Male Sprague-Dawley rats were exposed to 0, 0.5, 3, or 15 ppm HCHO for 6 h/d, 5 d/wk, for 8 or 16 wk. The preexposed animals and age-specific controls were then submitted to a HCHO nosepiece challenge at the same concentration that was received in the subchronic exposure. Very high nasal deposition was demonstrated in all measurements. There was a diminished maximum minute volume depression in the 16-wk group relative to the 8-wk group. The difference in response was not statistically associated with the subchronic preexposure concentration. The substantial recovery of all initially depressed responses that occurred during the challenges probably diminished the impact of the decreased maximum responses on the resulting nasal deposition over the course of the long-term exposures.

Absorption↗
PubMed1992

Ciliated respiratory epithelial surface changes after formaldehyde exposure.

The investigation sought to identify alterations of specific ciliated epithelial surface components after exposure to formaldehyde (HCHO) levels that decrease respiratory ciliary function. Bovine tracheae were reacted with an analog of N-hydroxysuccinimidobiotin to label epithelial surface-accessible components before exposure to HCHO. The tracheae were then exposed to 0, 16, 33, and 66 micrograms HCHO/cm2 epithelial surface for 30 min. Cilia were isolated from the epithelium, separated into membrane and internal axonemal portions, analyzed on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and either stained to detect proteins or transblotted to detect biotin-labeled components. Densitometric analysis of axoneme proteins showed a decrease in the total amount extracted with increased HCHO concentration, including axoneme-specific proteins, dynein, and tubulin. However, biotinylated proteins in the axoneme fractions proportionately increased. Membrane fractions showed little change in protein with increasing HCHO concentration. The majority of these is not biotin-labeled and thus not surface-accessible components. Biotinylated material in the membrane fractions showed a significant decrease with increased HCHO concentration, particularly of bands at 92, 98, and 105 kD. These data suggest that increasing HCHO exposure reduces both extractable ciliary axonemes and detergent-soluble surface components, possibly by stabilizing respiratory epithelial membranes. This process apparently strengthens association of certain surface components with the internal axoneme, thereby reducing subsequent solubilization in detergent.

Adenosine Triphosphatases↗
PubMed1984

Phenol interference in the mercury-free pararosaniline method and the chromotropic acid method for formaldehyde.

The modified pararosaniline method for formaldehyde which uses no poisonous mercury reagent is not affected by phenol/formaldehyde ratios ranging from 1 to 100, whereas such ratios caused almost total inhibition of the chromotropic acid method, even if water, 1% sodium bisulfite or 0.01 N H2SO4 were used to simulate different collection media. No influence of phenol also occurred even for 11 days of storage at room temperature before analysis.

Air Pollutants, Occupational↗
PubMed1987

Formate in urine as a biological indicator of formaldehyde exposure: a review.

The presence of a small amount of endogenously derived formate in human urine is normal; however, formate derived from the metabolism of formaldehyde, several other industrial compounds and some pharmaceuticals may elevate the urine formate concentration above the normally expected values. This elevation in the urine formate concentration presents the possibility of using this as a tool for monitoring exposure to chemicals. Unfortunately, the use of urine formate as a technique for monitoring personal chemical exposure has yet to be evaluated. This review identifies several potentially important variables that could alter the extent to which formate is eliminated through the urine and that could affect the accuracy of using urine formate concentration as an indicator of chemical exposure. Some potentially important confounders that have been identified, but not evaluated adequately, include dietary intake, nutritional status and exposure to cigarette smoke. Furthermore, the metabolism and elimination kinetics have yet to be adequately demonstrated in humans. Without having controlled for potential confounders in previous pharmacokinetic studies, it is unknown whether or not the large range and variation observed in human studies is due to the confounders or to innate individual variability. Given the poor understanding of the normal variation of formate concentration in the urine, the use of it as a biological indicator of chemical exposure becomes questionable. Without appreciable skin penetration, as in this case, the reliance upon air monitoring alone may be more practical. The evidence at this time suggests that the use of urine formate to monitor chemical exposure offers a broad opportunity for investigative research. At the present time, however, the interpretation of urine formate concentration in samples obtained from workers would be difficult.

Animals↗
PubMedDate not supplied

Determination of the dry matter disappearance and the crude protein degradability of the formaldehyde treated feeds in the rumen by in situ method.

Sunflower cake (SC), horse bean (HB), and alfalfa meal (AM) were treated with rising doses of formaldehyde (F) from 0.0, 0.2 ... 2.0 g F per 100 g crude protein. We have followed the differences of crude protein solubility, its degradability and disappearance of dry matter in the rumen as well as the amount of reversible bonded F from the F dose. With AM it was found a significant influence of ADF on the degradability and on the amount of acid-labile bonded F and/or on the decrease of N solubility. From the total N content the share of soluble nitrogen decreased in SC by 31%, HB by 24%, and in AM only by 12.5%. With the increase of the F dose its protective effect on proteins against the degradability mainly in SC and HB also rose significantly. The degradability of AM protein was influenced more by the incubation time than by the effect of treatment. The degradability of the SC proteins fell from 95% with untreated to 27% treated with the maximum dose. With AM it fell slowly from 84% to 74% by the determination coefficient R2 = 0.77. It was observed a marked decrease in HB only from the dose of 1.28% F. The changes in dry matter disappearance were similar to the changes in crude protein degradability and to the changes of solubility in SC and AM. The in situ method proved very suitable for the determination of the extent of degradability of the feed proteins in the rumen.

Animal Feed↗
PubMed2005

Bioconversion of methanol to formaldehyde: 1 by free whole cell and immobilized whole cell of yeast Hansenula polymorpha.

Modified methylotrophic yeast Hansenula polymorpha (HP A16) was used in this study, which was obtained with recrossing a leucine oxotrophic yeast and a wild type Hansenula polymorpha CB4732 and was discovered by Ogata et al. The yeast is grown with methanol as a sole carbon source in which methanol oxidase (MOX) is a key enzyme of methanol metabolism. Because of its stability and low substrate specificity, alcohol oxidase is of considerable interest for a range of biotechnological processes. Various methanol feeding regimes were evaluated in an effort to increase the biomass concentration and productivity that could be achieved from fermentations using the other Hansenula polymorpha species. This yeast was grown by batch fermentation. The effects of conditions of inoculation media for increasing amount of MOX enzyme in peroksizomes of yeast with MOX activity were observed. The highest MOX activity of yeast was found within optic density of grown media of OD600 1.5, at 0.35 microM of methanol as used an oxotrophic substrate, at 35 degrees C temperature, at pH 7.0 of 0.1 M potassium phosphate buffer (KPB), at 40 microL of buffered yeast cell volume and at the incubation time of 50 minutes. Whole yeast cells were cultivated at above optimized incubation conditions. The cells were immobilized within the polyacyrlamide gels by entrapment method. Free whole cells and immobilized whole cells were compared using bioconversion percentages of methanol to formaldehyde.

Alcohol Oxidoreductases↗
PubMed2002

Application of hydroalcoholic solutions of formaldehyde in preparation of acetylsalicylic acid gastro-resistant capsules.

Enteric coating of hard gelatin capsules by application of hydroalcoholic solutions of formaldehyde was studied and developed in accordance with previous publications. It is possible to affirm that this coating constitutes a simple, stable, reproducible, and inexpensive method, being a valid alternative to those which have been proposed. The aim of the present investigation is the preparation of acetylsalicylic acid gelatin capsules with good conditions of gastro-resistance and enteros solubility.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2005

Effect of formaldehyde gas exposure in a murine allergic contact hypersensitivity model.

To clarify the effect of formaldehyde (FA) gas exposure on contact hypersensitivity (CHS), CHS reactions against 2,4,6-trinitrochlorobenzene (TNCB) was studied in BALB/c mice with a low dose of FA gas exposure. The TNCB-induced CHS reactions were slightly suppressed by the FA gas exposure immediately after sensitization, whereas they were significantly enhanced and prolonged in mice continuously exposed to FA gas before and after sensitization. We showed that exposure to FA gas enhanced the Th2 dominant responses in draining lymph node (LN) in early stage of CHS. In contrast, T cell subsets and their intracellular cytokine production in the draining LN were similar during the early stage of CHS by FA gas exposure during the sensitization phase. The percentage of CD8+ T cells was increased, and the percentage of CD4+CD25+ T cells was decreased in the FA gas-exposed group at 72 hr after elicitation. These results indicate that FA gas-exposed might influence regulatory T cells. Furthermore, in the chronic CHS model that was repetitively elicited with TNCB, more intensive and prolonged CHS reactions, and increased numbers of mast cells were found in the FA gas-exposed group at 4 hr after elicitation than in the control group, FA gas exposure may alter the intensity of allergic CHS.

Administration, Cutaneous↗
PubMed2005

Cross-linking of gelatin capsules with formaldehyde and other aldehydes: an FTIR spectroscopy study.

Attenuated total reflection Fourier transform infrared spectroscopy (FTIR) has been used to study cross-linking in hard gelatin capsules induced by exposure to formaldehyde, acetaldehyde, and propionaldehyde. These aldehydes are known to cause cross-linking between the amino acid chains of gelatin. Using FTIR spectroscopy, it is possible to analyze the cross-linking mechanisms by studying changes in the vibrational bands of the gelatin spectrum. The FTIR spectrum changes over time when the capsules are left in an aldehyde-rich environment. Analysis of the spectra shows that the early observed spectral changes conform to reaction intermediates proposed in previous work based on nuclear magnetic resonance experiments, specifically, the formation of amine methyl alcohol of arginine and lysine residues. Further spectral changes appear to be mostly from unreacted aldehydes absorbed to the gelatin, although a minor shift of the amide II peak is attributed to cross-link formation.

Aldehydes↗
PubMed1967

The use of formaldehyde-treated 131-I-albumin in the study of digestive vacuoles and some properties of these particles from mouse liver.

The trichloroacetic acid-soluble radioactivity released during incubation of mouse liver particles containing intravenously injected formaldehyde-treated (131)I-albumin consisted almost entirely of (131)I-iodotyrosine. The material was shown to be excreted into the medium and was not due to disruption of the particles by acid. Triton X-100 or the absence of sucrose in the medium inhibited hydrolysis of the particle-associated labeled protein. This inhibition was due to disruption of the digestive vacuoles and dilution of the protein and cathepsins in the suspending medium. These results and other experimental evidence strongly suggest that the (131)I-albumin-containing liver particles are digestive vacuoles. The results also establish that (131)I-albumin may be used to study these vacuoles. High concentrations of sucrose (1 M) inhibited degradation of intraparticulate protein. However, 1 M salts inhibited only the rate of the digestion. Sucrose had an inhibitory effect on a crude cathepsin preparation, and salts stimulated the activity when (131)I-albumin was used as substrate. The effect of high sucrose concentrations as an inhibitor of protein hydrolysis within digestive vacuoles was, therefore, most likely due principally to an inhibition of cathepsin activity within the vacuoles. The effect of salt was probably caused by a stimulation of both intra- and extra-particulate cathepsin activities, although 0.5-1.0 M KCl appeared to protect the particles.

Albumins↗
PubMed1981

Polyclonal activation of human peripheral blood B lymphocytes by formaldehyde-fixed Salmonella paratyphi B. I. Immunoglobulin production without DNA synthesis.

A "new" polyclonal activator of human peripheral blood B cells, formaldehyde-fixed Salmonella paratyphi B, is described. This bacterium does not stimulate cell proliferation as measured by incorporation of tritiated thymidine but does stimulate a subpopulation of B cells to secrete large amounts of IgM, IgG, and IgA in 7-day cell cultures. The immunoglobulins (Ig) produced by cells responding to S. paratyphi B are not specific antibodies against the bacterial antigens. In comparison with other B cell activators (pokeweed mitogen, Staphylococcus aureus Cowan I, and lipopolysaccharide), S. paratyphi B stimulation produced greater amounts of IgM but less IgG than pokeweed mitogen (PWM) or S. aureus Cowan I; lipopolysaccharide failed to stimulate significant Ig production on day 7 in most cases. In addition, the response to S. paratyphi apparently did not require T cell collaboration. These results suggest that the B cell subpopulation(s) responding to S. paratyphi B may be more differentiated B cells than those responding to either PWM or S. aureus Cowan I. Peripheral blood mononuclear cells from five patients with common variable immunodeficiency without evidence of abnormal suppressor T cells or monocytes failed to respond to S. paratyphi B, whereas cells from two of the same patients responded well to S. aureus Cowan I and partially to PWM. Thus, S. paratyphi B appears to be superior to other B cell activators for studies of B cell function in normal and abnormal states.

B-Lymphocytes↗
PubMed1969

Effect of formaldehyde and glutaraldehyde on electrical properties of cardiac Purkinje fibers.

The effects of formaldehyde, glutaraldehyde, 1-fluoro-2,4-dinitrobenzene, and 1,5-difluoro-2,4-dinitrobenzene on the electrophysiological properties of cardiac Purkinje fibers were studied. At concentrations of 2.5 mM the aldehydes produced a transient hyperpolarization, lengthening of the plateau of the action potential, and an increase in action potential overshoot and upstroke velocity. If exposure to aldehyde was continued, the fiber failed to repolarize after an action potential and the membrane potential stabilized at about -30 mv. If exposure was terminated before this, recovery was usually complete. At the time the fibers were hyperpolarized the input resistance was increased without much change in length constant, leading to an increase in both calculated membrane resistance and calculated core resistance. Although it was anticipated that an effect of the aldehydes on the membrane was to increase fixed negative charge, it was difficult to explain all the electrophysiological changes on this basis. The major effects of the fluorobenzene compounds were not the same; they produced a shortening of the action potential and a rapid loss of excitability.

Action Potentials↗
PubMed1999

The formaldehyde ortho/para ratio as a probe of dark cloud chemistry and evolution.

We present measurements of the H2CO ortho/para ratio toward four star-forming cores, L723, L1228, L1527, and L43, and one quiescent core, L1498. Combining these data with earlier results by Minh et al., three quiescent cores are found to have ortho/para ratios near 3, the ratio of statistical weights expected for gas-phase formation processes. In contrast, ortho/para ratios are 1.5-2.1 in five star-forming cores, suggesting thermalization at a kinetic temperature of 10 K. We attribute modification of the ortho/para ratio in the latter cores to formation and/or equilibration of H2CO on grains with sub-sequent release back into the gas phase due to the increased energy inputs from the forming star and outflow. We see accompanying enhancements in the H2CO abundance relative to H, to support this idea. The results suggest that the formaldehyde ortho/para ratio can differentiate between quiescent cores and those in which low-mass star formation has occurred.

Astronomical Phenomena↗
PubMed1996

Detection of a new interstellar molecular ion, H2COH+ (protonated formaldehyde).

A new interstellar molecular ion, H2COH+ (protonated formaldehyde), has been detected toward Sgr B2, Orion KL, W51, and possibly in NGC 7538 and DR21(OH). Six transitions were detected in Sgr B2(M). The 1(1,0)-1(0,1) transition was detected in all sources listed above. Searches were also made toward the cold, dark clouds TMC-1 and L134N, Orion (3N, 1E), and a red giant, IRC + 10216, without success. The excitation temperatures of H2COH+ are calculated to be 60-110 K, and the column densities are on the order of 10(12)-10(14) cm-2 in Sgr B2, Orion KL, and W51. The fractional abundance of H2COH+ is on the order of 10(-11) to 10-(9), and the ratio of H2COH+ to H2CO is in the range 0.001-0.5 in these objects. The values in Orion KL seem to be consistent with the "early time" values of recent model calculations by Lee, Bettens, & Herbst, but they appear to be higher than the model values in Sgr B2 and W51 even if we take the large uncertainties of column densities of H2CO into account. We suggest production routes starting from CH3OH may play an important role in the formation of H2COH+.

Astronomical Phenomena↗
PubMed2005

A comparative study of ethylene oxide gas, hydrogen peroxide gas plasma, and low-temperature steam formaldehyde sterilization.

OBJECTIVE: To compare the efficacies of ethylene oxide gas (EOG), hydrogen peroxide gas plasma (PLASMA), and low-temperature steam formaldehyde (LTSF) sterilization methods. METHODS: The efficacies of EOG, PLASMA, and LTSF sterilization were tested using metal and plastic plates, common medical instruments, and three process challenge devices with narrow lumens. All items were contaminated with Bacillus stearothermophilus spores or used a standard biological indicator. RESULTS: EOG and LTSF demonstrated effective killing of B. stearothermophilus spores, with or without serum, on plates, on instruments, and in process challenge devices. PLASMA failed to adequately sterilize materials on multiple trials in several experiments, including two of three plates, two of three instruments, and all process challenge devices. CONCLUSIONS: Our results suggest that PLASMA sterilization may be unsuccessful under certain conditions, particularly when used for items with complex shapes and narrow lumens. Alternatively, LTSF sterilization demonstrates excellent efficacy and is comparable to EOG sterilization. LTSF could potentially act as a substitute if EOG becomes unavailable due to environmental concerns.

Equipment and Supplies↗
PubMed1994

Immunohistochemical evaluation of myeloid leukemia infiltrates (granulocytic sarcomas) in formaldehyde-fixed, paraffin-embedded tissue.

Paraffin sections of granulocytic sarcomas (GS) (n = 30) were immunohistochemically evaluated for CD3, CD15 (LeuM1), CD20 (L26), CD31, CD34, CD43, CD45, CD68 (KP1), lysozyme, myeloperoxidase (BM1), CD45RO (UCHL1), and LN5 with an avidin-biotin amplification system and a peroxidase-based color development system with DAB as a chromogen. CD45 positivity was present in all lymphomas and 24 of 25 granulocytic sarcomas. Lysozyme and CD43 labeled 26 of 29 granulocytic sarcomas, showing intense cytoplasmic staining. LN5 (membrane-staining) and CD68 (subtle cytoplasmic caplike staining) were found in 20 of 30 cases, often only focally. BM1 and CD15 mainly labeled maturing granulocytes and mostly were negative in primitive myeloid cells. Myeloid progenitor cell antigens CD31 and CD34 were seen in 7 and 12 of 30 cases, respectively. They seemed to recognize different subsets of myeloid leukemia infiltrates (16 cases positive for at least one); the use of CD31 and CD34 for defining these subsets should be evaluated further. Features suggesting a dual phenotype--T-cell and myeloid (positive for CD3, CD68, and lysozyme)--were documented in two cases. In contrast, lymphoblastic lymphomas (n = 4) were positive for CD3 and CD43 but negative for CD68, lysozyme, CD31, CD34, LN5, and myeloperoxidase. Lymphocytic lymphomas (n = 10) were positive for CD20 and CD43 but negative for all other markers. Small, round-cell tumors (n = 15) were negative for all markers. If T-cell and B-cell differentiation can be excluded with other markers, CD43+ is a sensitive marker for myeloid differentiation. Our results show that several markers are useful in the identification of myeloid leukemia infiltrates and in distinguishing them from lymphoblastic and lymphocytic lymphomas and small round-cell tumors in formaldehyde-fixed, paraffin-embedded tissue.

Adult↗
PubMed1990

Reduction of exposure to solvents and formaldehyde in surface-coating operations in the woodworking industry.

A 1-year study has been performed at a company which manufacturers office furniture, and can be subdivided into three phases: measurement of exposure prior to remedial measures; remedial measures whose purpose was to reduce exposure; and new measurements after remedial measures. Remedial measures concentrated on changes which would reduce exposure to solvents. These measures fall into two categories: (i) the training of employees about the way airborne pollutants spread and ways of avoiding exposure; and (ii) locating and eliminating important sources of emission. Employees were trained mainly by the PIMEX (PIcture Mix EXposure) method for showing them how exposure depended on methods of work and conditions at the workplace. The most important sources of solvent emissions were pin-pointed by the GridMap method. The results show that exposure can be greatly reduced through training, adjustment of existing equipment and minor technical measures. This is the case even when exposure is initially at a concentration which is clearly below hygienic limit values. This approach should also reduce exposure to formaldehyde, though this could not be evaluated because the raw materials used changed during the study.

Environmental Exposure↗