[On the problem of the study of the chemical air pollution with chlororganic hydrocarbons at productions of polyvinyl chloride and epichlorohydrin].

Hygienic assessment of working conditions at the chemical productions of polyvinyl chloride (PVC) and epichlorohydrin (EPCH) in East Siberia has shown that the employees are exposed to the chlororganic hydrocarbons of hazard category 1-2, out of them there were found to be more toxical pollutants such as vinyl chloride, 1.2-dicloroethane in the production of polyvinyl chloride; allyl chloride and epichlorohydrin in the production of epichlorohydrin. Multistageness of the technological processes, the absence of the isolation of main stages of the technological processes as well as the heating microclimate contribute to the chemical pollution of the air environment.

[The specific features of microbiocenoses in children living under conditions of anthropogenic pressing].

The specific features of enteric and nasopharyngeal microbiocenoses and the species composition of bifidobacteria have been studied in children living in the industrial towns of the Irkutsk Region under the existing anthropogenic load. Ambient air pollution is characterized and a presumptive human health risk assessed.

[Biomonitoring of formaldehyde in the urinary samples from the pediatric population in the Irkutsk Region].

Formaldehyde is one of the major pollutants of both ambient and indoors air. Thus, by comparing the concentrations of formaldehyde in ambient air (on study days) and in the air of classes and living rooms, the study has demonstrated that they may be 13.5 and 10.

[Methyl sulphides and their metabolites in biologic materials of workers engaged into sulfate pulping].

The authors studied serum and urine levels of methyl sulphides in workers engaged into sulfate pulping and exposed to methyl sulphides. Blood serum was studied only for dimethyldisulfide. Urine appeared to contain no methyl sulphides, but finding was increased urinary excretion of sulfates which are metabolites of methyl sulphides.

On the mechanism of ion formation from the aqueous solutions irradiated with 3 microm IR laser pulses under atmospheric pressure.

The mechanism of atmospheric pressure (AP) laser ionization of water and water/glycerol liquid samples at a 3-microm wavelength is studied experimentally. For the ion desorption, an in-house built Yb : YAG-pumped optical parametric oscillator (OPO) infrared (IR) laser has been coupled with AP MALDI ion source interfaced to an ion trap mass spectrometer (MS). It has been shown that water is primarily responsible for ion generation in water/glycerol samples, while glycerol increases the solution viscosity and decreases the water evaporation rate and sample losses.

Mass spectrometry of N-linked oligosaccharides using atmospheric pressure infrared laser ionization from solution.

An atmospheric pressure (AP) infrared (IR) laser ionization technique, implemented on a quadrupole ion trap mass spectrometer, was used to analyze underivatized, N-linked oligosaccharides in solution. Experiments were conducted on an atmospheric pressure infrared ionization from solution (AP-IRIS) ion source which differed from previous AP IR matrix-assisted laser desorption/ionization (MALDI) interfaces in that the ion source operated in the absence of an extraction electric field with a higher power 2.94 microm IR laser.

[Evaluation of a chemical factor during fires].

The working conditions of firemen during active service cannot be assessed without characterizing the degree of ambient gas contamination with toxic substances. Firemen extinguish fires and liquidate accidents under difficult conditions, which presents a threat to their life and health. Fire-induced combustion products can emit as high as 100 types of chemical compounds.

Detection of cyclic lipopeptide biomarkers from Bacillus species using atmospheric pressure matrix-assisted laser desorption/ionization mass spectrometry.

A novel approach to microbial detection using atmospheric pressure matrix-assisted laser desorption/ionization with an ion trap mass spectrometer to analyze whole cell bacteria is introduced. This new approach was tested with lyophilized spores and cultures of Bacillus globigii (BG) grown on agar media for 4 days or longer. At each stage of growth, it was found that biomarkers, identified as cyclic lipopeptides known as fengycin and surfactin, could be detected by pulsed ultraviolet laser irradiation of intact BG cells (approximately 5 mg) cocrystallized with alpha-cyano-4-hydroxycinnamic acid.

Matrix-assisted laser desorption/ionization detection of polymerase chain reaction products by utilizing the 5'-3' exonuclease activity of Thermus aquaticus DNA polymerase.

The 5'-3' exonuclease activity of DNA polymerase was utilized in the polymerase chain reaction system to generate a specific signal concomitant with amplification. These signals were detected by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). This method obviates the need to perform extensive DNA purification of reaction products that is often necessary for detecting larger DNA molecules by mass spectrometry.

Atmospheric pressure laser desorption/ionization on porous silicon.

A recently developed commercial atmospheric pressure matrix-assisted laser desorption/ionization (AP-MALDI) source (MassTech, Inc.) was modified to adopt commercially available DIOS plates (Mass Consortium Corp.) for the studies of laser desorption from the surface of porous silicon under atmospheric pressure conditions.

Desorption/ionization of biomolecules from aqueous solutions at atmospheric pressure using an infrared laser at 3 microm.

A new atmospheric pressure (AP) infrared (IR) matrix-assisted laser desorption/ionization (MALDI) ion source was developed and interfaced with a Thermo Finnigan LCQ ion trap mass spectrometer. The source utilized a miniature all-solid-state optical parametric oscillator (OPO)-based IR laser system tunable in the lambda = 1.5-4 microm spectral range and a nitrogen ultraviolet (UV) laser (lambda = 337 nm) for use in comparative studies.

Laser desorption mass spectrometry for microbial DNA analysis.

Recently, we demonstrated that a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOF MS) can be used to determine the molecular weight of polymerase chain reaction (PCR) products of intact 16S rRNA regions and to profile their restriction digests. This is the first time that MALDI-TOF MS with ultraviolet (UV) photoionization has been used to analyze a PCR product of approximately 1600 nucleotides in length.

Nonresonant MALDI of oligonucleotides: mechanism of ion desorption.

Oligonucleotide ions have been detected using matrix-assisted laser desorption/ionization (MALDI) under nonresonant laser irradiation of the sample. When mass resolution was not limited by adduct attachment to the analyte ions, the nonresonant MALDI spectra demonstrated better resolution than the spectra acquired with resonant ultraviolet irradiation. We found that preparation of thin-film samples on absorbing substrate surfaces was critical for the success of NR-MALDI.

Regulation of CD34 transcription by Sp1 requires sites upstream and downstream of the transcription start site.

CD34 is a cell surface glycoprotein expressed on hematopoietic stem and progenitor cells, but not on fully differentiated cells in the peripheral blood. To better understand the molecular regulation of early hematopoiesis, we are elucidating the mechanisms of CD34 transcriptional regulation. By deletion analysis we identify a 39-bp element in the proximal region of murine CD34 promoter that is critical for promoter activity.

Matrix-assisted laser desorption/ionization time-of-flight analysis of Bacillus spores using a 2.94 microm infrared laser.

The performance of infrared (2.94 microm) and ultraviolet (337 nm) lasers were compared for analysis of purified spores of B. subtilis, B.

A nuclear factor Y (NFY) site positively regulates the human CD34 stem cell gene.

Proper regulation of the human CD34 gene requires a combinatorial action of multiple proximal and long-range, cis elements. This report shows that, like the murine CD34 5' untranslated region (UTR), the corresponding region of the human CD34 gene is necessary for optimal promoter activity. We localized the most critical element of this region to base pairs +48/+75.

Gender identification by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

A rapid, simple, and reliable gender determination of human DNA samples was successfully obtained using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Detection sensitivity reached 0.01 ng or less for DNA samples.

Detection of trinucleotide expansion in neurodegenerative disease by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

Genotyping of the dentatorubral-pallidoluysian atrophy (DRPLA) locus in six patient samples, representing four normal individuals and two DRPLA patients, was successfully obtained using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). DRPLA is a dominantly inherited neurodegenerative disorder associated with the expansion of an unstable trinucleotide (CAG) repeat. The accurate determination of repeat length utilizing MALDI supports the use of this methodology for the analysis of genes containing unstable CAG trinucleotide repeats.

Sequencing DNA using mass spectrometry for ladder detection.

Sequencing of DNA fragments of 130 and 200 bp using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for DNA ladder detection was demonstrated. With further improvement in mass resolution and detection sensitivity, mass spectrometry shows great promise for routine DNA sequencing in the future.

Matrix-assisted laser desorption/ionization for short tandem repeat loci.

Matrix-assisted laser desorption/ionization was used for the detection of four base short tandem repeats (STR) for clinical samples using a time-of-flight mass spectrometer. Since STR plays an important role in genetic disease and human identification, this work indicates that laser desorption mass spectrometry has the potential to achieve rapid DNA typing for both forensic applications and genetic disease diagnosis.

[Urinary sulfates as a biologic indicator of exposure to methylsulfate compounds in manufacture of sulfate cellulose].

The authors studied urine excretion of sulfates before and after a shift in workers engaged into brewing and flushing shops of sulfate cellulose production, who are exposed to various amounts of methyl sulfate compounds. Significant increase of urine sulfate appeared by the end of the shift and correlated with intensity of the air pollution with methyl sulfate compounds. Lower urine excretion of sulfates occurred with longer length of service.