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In the pseudo ternary MgO-Si3N4-Al2O3 system at 1800 °C the occurrence of liquid phase is limited to areas near the MgO-Si3N4 line, close to Si3N4. The area near the MgO-Al2O3 line is interesting from the point of view of refractory materials. The results of investigations into the properties and microstructure of magnesia-spine! materials with oxynitride and nitride matrix obtained bysintering are presented. The materials with a matrix composed of AIN polytypoids were characterized by very high refractoriness under load (RUL) in reducing conditions (T0.6>1700°C) and relatively high RUL in air (mm T0.5> 1620°C). The TG curves showed that the oxidation course was similar to and depended on the composition and mixture of samples. A very good correlation was found between the calculated values of R coefficient and resistance to thermal shocks sustained by the cylinders subjected to sudden heating up to 950 °C and cooling. [ABSTRACT FROM AUTHOR]

The implementation of medical software and artificial intelligence (AI) algorithms into routine clinical cytometry diagnostic practice requires a thorough understanding of regulatory requirements and challenges throughout the cytometry software product lifecycle. To provide cytometry software developers, computational scientists, researchers, industry professionals, and diagnostic physicians/pathologists with an introduction to European Union (EU) and United States (US) regulatory frameworks. Informed by community feedback and needs assessment established during two international cytometry workshops, this article provides an overview of regulatory landscapes as they pertain to the application of AI, AI-enabled medical devices, and Software as a Medical Device in diagnostic flow cytometry. Evolving regulatory frameworks are discussed, and specific examples regarding cytometry instruments, analysis software and clinical flow cytometry in-vitro diagnostic assays are provided. An important consideration for cytometry software development is the modular approach. As such, modules can be segregated and treated as independent components based on the medical purpose and risk and become subjected to a range of context-dependent compliance and regulatory requirements throughout their life cycle. Knowledge of regulatory and compliance requirements enhances the communication and collaboration between developers, researchers, end-users and regulators. This connection is essential to translate scientific innovation into diagnostic practice and to continue to shape the development and revision of new policies, standards, and approaches., (© 2024 International Clinical Cytometry Society.)

Flow cytometry is a key clinical tool in the diagnosis of many hematologic malignancies and traditionally requires close inspection of digital data by hematopathologists with expert domain knowledge. Advances in artificial intelligence (AI) are transferable to flow cytometry and have the potential to improve efficiency and prioritization of cases, reduce errors, and highlight fundamental, previously unrecognized associations with underlying biological processes. As a multidisciplinary group of stakeholders, we review a range of critical considerations for appropriately applying AI to clinical flow cytometry, including use case identification, low and high risk use cases, validation, revalidation, computational considerations, and the present regulatory frameworks surrounding AI in clinical medicine. In particular, we provide practical guidance for the development, implementation, and suggestions for potential regulation of AI-based methods in the clinical flow cytometry laboratory. We expect these recommendations to be a helpful initial framework of reference, which will also require additional updates as the field matures., (© 2024 International Clinical Cytometry Society.)

Breastfeeding may have a positive effect on glucose metabolism and insulin sensitivity, which may reduce the risk of developing diabetes following gestational diabetes mellitus (GDM). This study aimed to evaluate the effect of breastfeeding and GDM on the body mass composition of the studied women, the levels of leptin, ghrelin, adiponectin, resistin, and insulin, and weight loss during the 6-8-week postpartum period and 1 year after childbirth., Materials and Methods: The study group included 42 women with a singleton pregnancy, diagnosed with GDM between the 24th and 28th week of gestation. The control group consisted of 28 non-diabetic women with a singleton pregnancy. This study was carried out at 6-8 weeks as well as at 1 year postpartum. The women were subjected to body weight measurements and body composition analysis performed using a professional body composition analyzer TANITA DC-430 S MA. Waist circumference and subcutaneous fat was measured. Blood for laboratory tests was taken in the morning, on an empty stomach., Results: It was shown that, regardless of diabetes, exclusive breastfeeding had a significant impact on weight loss at 6-8 weeks postpartum ( p = 0.014785) and lower insulin levels ( p = 0.047). However, there was no effect of breastfeeding on the women's anthropometric measurements or hormone levels one year after delivery, except for the thickness of subcutaneous adipose tissue, which was significantly lower in breastfeeding women ( p = 0.03). One year after delivery, breastfeeding women had a lower BMI ( p = 0.0014), less-thick subcutaneous adipose tissue ( p < 0.001), and a lower risk of obesity ( p = 0.016). There were also higher insulin and ghrelin levels in both breastfeeding and non-breastfeeding women ( p < 0.001), and lower resistin levels in non-breastfeeding women ( p = 0.004). Women who had diabetes during pregnancy had a significantly reduced waist circumference and subcutaneous fat thickness after one year ( p < 0.001 and p = 0.05, respectively)., Conclusions: Having diabetes during pregnancy did not significantly affect the results of anthropometric measurements and hormone levels noted at 6-8 weeks after delivery (the only exception was the thickness of subcutaneous fat tissue, which was greater in women without GDM). This may indicate normalization of carbohydrate metabolism after childbirth; however, the observation period is too short to elucidate long-term metabolic effects. This suggests the need for further research related to GDM and breastfeeding.

The total amount of fat in the milk of nursing mothers depends on maternal reserves, as well as food intake and its synthesis in the mammary glands. The aim of this study was to assess the contents of fatty acids in the milk of women from the West Pomeranian region of Poland with regards to supplementation and the amount of adipose tissue. We also wanted to find out whether these women, who have direct access to the sea and potential access to fresh marine fish, have higher levels of DHA., Methods: We analyzed milk samples obtained 6-7 weeks postpartum from 60 women. The content of fatty acid methyl esters (FAME) in lipids was determined by gas chromatography-mass spectrometry (GC/MS) using a Clarus 600 device (PerkinElmer)., Results: Women using dietary supplements had significantly higher levels of docosahexaenoic acid (DHA) (C22:6 n-3) ( p = 0.000) and eicosapentaenoic acid (EPA) (20:5 n-3) ( p = 0.000). The levels of eicosatrienoic acid (ETA) (C20:3 n-3) and γ-linolenic acid (GLA) increased with the amount of body fat, and the level of DHA was lowest in subjects where body fat exceeded 40% ( p = 0.036)., Conclusions: The contents of fatty acids in the milk of women from the West Pomeranian region of Poland were similar to that reported by other authors. The levels of DHA in women using dietary supplements was also comparable to the values reported worldwide. BMI had an effect on the levels of ETE and GLA acids.

Introduction: Generalised anxiety disorder (GAD) is one of the most common mental disorders. The psychosocial factors that may lead to generalised anxiety disorders include stress, traumatic events, conscious and unconscious internal conflicts, and low social and economic status. Imprisonment and forced isolation may favour the development of depression or anxiety disorders in inmates. Thus, this study aimed to analyse the prevalence of generalised anxiety disorder (GAD) in the population of inmates detained in one of the largest penitentiary units in north-eastern Poland. Materials and Methods: The data comes from 2017 and includes information on 635 male inmates incarcerated at the Czerwony Bór Prison. The information comes from the health records of individual inmates, kept by the prison outpatient clinician, and documented consultations with doctors of units outside the prison. The classification of generalised anxiety disorders (F41.1) was made in accordance with the 10th Revision of the International Statistical Classification of Diseases and Health Problems and the clinical diagnosis made by a psychiatrist. The Mann-Whitney test was used to compare quantitative data without normal distribution, chi-squared test or Fisher exact test for comparing qualitative data. A one-dimensional and multi-dimensional logistic regression model was used to examine the impact of the prison type on the prevalence of generalised anxiety disorder. Results: Generalised anxiety disorder was observed among 44 prisoners (6.9%), most often in the age range 30-39 years and among men younger than 30 years, respectively 40.9 and 31.8% of all diagnosed. The average age of patients was 34.6 years. The least number of prisoners with GAD was in the age group 50-59 (2.3%). Nearly 66% of patients were prisoners detained in a closed type prison; the chance of generalised anxiety disorder was three times higher than among the prisoners in a half-open and open type facility. Generalised anxiety disorder was diagnosed significantly more often with those currently serving a prison sentence than those before incarceration. Conclusions: In Polish conditions, the importance of the problem associated with GAD is evidenced by a significant increase in its prevalence in the prison environment and a three times higher chance of developing generalised anxiety disorder among prisoners in a closed type institution, which calls for highly organised psychiatric care and increased availability of psychological assistance for prisoners., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Stawinska-Witoszynska, Czechowska, Moryson and Wieckowska.)

Introduction: The National Health Fund guarantees to insured persons free dental treatment as part of a catalog of scopes and benefits, such as dental treatment. Among the services included in the appendix there is a dental plaque removal procedure, which can be performed in adults once every 12 months or once every 6 months in the case of pregnant and puerperal women. This procedure involves breaking down the bacterial biofilm above and below the gingiva, rinsing it in vases with water from the periodontal area, and additionally, through the cavitation effect, it causes the implosion of air bubbles, directly destroying bacterial cells., Materials and Methods: The analysis covered 2,114 patients aged 18-89 who visited the dentist from 01/01/2019 to 31/12/2019. The dental clinic was located in a medium-sized town in the Podlaskie Voivodeship. The dental plaque removal procedures were performed on patients by dentists and then coded in accordance with the ICD9 Basic Edition Dictionary ICD9 CM (5.18) "23.1601 - Removal of plaque from 1/2 of the dental arch", respectively. The visits analyzed for this study were performed in the period from 01/01/2019 to 31/12/2019. In the following epidemiological descriptive study, secondary sources of information were used, in the form of collective reports generated from electronic records, which are stored in the dental clinic that provides dental care for patients under an agreement with the National Health Fund for general dental treatment., Results: The total number of women undergoing the plaque removal procedure was significantly higher than the number of men. The distribution of patients in different age groups was uneven. The highest percentage of patients undergoing the dental plaque removal procedure occurred in the age groups of 18-29 and 30-39 years - 21% and 29% of all respondents, respectively. The lowest number of patients was found in the age group of 80-89 years (1%).There is a statistical difference in the total number of dental procedures and in each age group in favor of women in each group, except the 60-79 age group. The greatest number of dental plaque removal procedures, compared to other procedures, was performed in men aged 30-39 years. Among men, along with the increase in age up to the age of 60, the number of dental plaque removal procedures decreased by an average of 10%, a drastic decrease occurred at the age of 70-79 - only 10% of procedures were dental plaque removal procedures. Among women aged 30-59 who were patients of the clinic, the percentage of women with dental plaque removal was about 30%, only in the age group over 80 the percentage of women who underwent the procedure fell to less than 10%., Conclusions: The results of the study show that the sex and age of the inhabitants of the Łomża region are significant variables related to the procedures of removing plaque in a dental office. Observation showing a decrease in the number of these procedures with increasing age of patients and their more frequent occurrence in women generally requires detailed studies identifying the main determinants of existing relationships., (© National Institute of Public Health – National Institute of Hygiene.)

Background: For a large part of the prisoners population, the prevalence of many diseases and the number of risk factors are greater than for the general population. In this work, we present an analysis of the prevalence of epilepsy and its co-occurrence with alcohol dependence among prisoners in a Polish penitentiary., Methods: One and multidimensional logistic regression was used to present the relationship between epilepsy and the co-occurrence of alcohol dependence and of other variables like: the prisoners' age, their classification, the unit type, the length of the stay in the penitentiary, and professional activity., Results: More than 7% of the prisoners had epilepsy. The prevalence was significantly higher in the 40-49 age group and among prisoners aged 50 and older. For prisoners suffering from alcohol dependence, the probability of epilepsy was over four times higher than for prisoners who did not suffer from that condition (OR [95%CI] = 4.09 [1.82-9.17], p = 0.001]., Conclusions: The obtained results show that the prevalence of epilepsy and alcohol dependence in the studied prisoner population was much higher than in the general population of Poles and that alcohol dependence was strongly correlated with epilepsy, independent from other variables. The research allowed to assess the size of the analyzed problem among convicts, however, bearing in mind the multifactorial etiology of epilepsy, the cause and effect relationship between exposure to alcohol and its occurrence would require further in-depth analytical studies taking into account other etiological factors of this disease.

Receptor occupancy measurements demonstrate the binding of a biotherapeutic agent to its extra-cellular target and represent an integral component of the pharmacodynamic (PD) portfolio utilized to advance the development and commercialization of a therapeutic agent. Coupled with traditional pharmacokinetic (PK) assessments derived from serum drug concentration, receptor occupancy data can be used to model PK/PD relationships and validate dose selection decisions throughout the drug development lifecycle. Receptor occupancy assays can be even more challenging to develop than other flow cytometric methods (e.g. surface immunophenotyping). In addition to typical considerations regarding stability of the cell type of interest, stability of the target-bound therapeutic agent and stability of the target receptor must be taken into account. Reagent selection is also challenging as reagents need to be evaluated for the potential to compete with the therapeutic agent and bind with comparable affinity. This article provides technical guidance for the development and validation of cytometry-based receptor occupancy assays., (© 2016 International Clinical Cytometry Society.)

The measurement of the binding of a biotherapeutic to its cellular target, receptor occupancy (RO), is increasingly important in development of biologically-based therapeutic agents. Receptor occupancy (RO) assays by flow cytometry describe the qualitative and/or quantitative assessment of the binding of a therapeutic agent to its cell surface target. Such RO assays can be as simple as measuring the number of cell surface receptors bound by an antireceptor therapeutic agent or can be designed to address more complicated scenarios such as internalization or shedding events once a receptor engages the administered therapeutic agent. Data generated from RO assays can also be used to model whether given doses of an experimental therapeutic agent and their administration schedules lead to predicted levels of receptor occupancy and whether the receptor is modulated (up or down) on cells engaged by the therapeutic agent. There are a variety of approaches that can be used when undertaking RO assays and with the ability to measure distinct subsets in heterogeneous populations, flow cytometry is ideally suited to RO measurements. This article highlights the importance of RO assays on the flow cytometric platform in the development of biotherapeutic agents., (© 2016 The Authors Cytometry Part B: Clinical Cytometry Published by Wiley Periodicals, Inc.)

The opportunistic pathogen Pseudomonas aeruginosa expresses a type 3 secretion system (T3SS) strongly associated with bacterial virulence in murine models and human patients. T3SS effectors target host innate immune mechanisms, and T3SS-defective mutants are cleared more efficiently than T3SS-positive bacteria by an immunocompetent host. Nonetheless, T3SS-negative isolates are recovered from many patients with documented P. aeruginosa infections, leading us to test whether T3SS-negative strains could have a selective advantage during in vivo infection. Mice were infected with mixtures of T3SS-positive WT P. aeruginosa plus isogenic T3SS-OFF or constitutively T3SS-ON mutants. Relative fitness of bacteria in this acute pneumonia model was reflected by the competitive index of mutants relative to WT. T3SS-OFF strains outcompeted WT PA103 in vivo, whereas a T3SS-ON mutant showed decreased fitness compared with WT. In vitro growth rates of WT and T3SS-OFF bacteria were determined under T3SS-inducing conditions and did not differ significantly. Increased fitness of T3SS-OFF bacteria was no longer observed at high ratios of T3SS-OFF to WT, a feature characteristic of bacterial cheaters. Cheating by T3SS-OFF bacteria occurred only when T3SS-positive bacteria expressed the phospholipase A2 effector Exotoxin U (ExoU). T3SS-OFF bacteria showed no fitness advantage in competition experiments carried out in immunodeficient MyD88-knockout mice or in neutrophil-depleted animals. Our findings indicate that T3SS-negative isolates benefit from the public good provided by ExoU-mediated killing of recruited innate immune cells. Whether this transient increase in fitness observed for T3SS-negative strains in mice contributes to the observed persistence of T3SS-negative isolates in humans is of ongoing interest.

We show proof of principle for assessing compound biodegradation at 1-2 mg C per L by measuring microbial community growth over time with direct cell counting by flow cytometry. The concept is based on the assumption that the microbial community will increase in cell number through incorporation of carbon from the added test compound into new cells in the absence of (as much as possible) other assimilable carbon. We show on pure cultures of the bacterium Pseudomonas azelaica that specific population growth can be measured with as low as 0.1 mg 2-hydroxybiphenyl per L, whereas in mixed community 1 mg 2-hydroxybiphenyl per L still supported growth. Growth was also detected with a set of fragrance compounds dosed at 1-2 mg C per L into diluted activated sludge and freshwater lake communities at starting densities of 10(4) cells per ml. Yield approximations from the observed community growth was to some extent in agreement with standard OECD biodegradation test results for all, except one of the examined compounds.

Chemical pollution is known to affect microbial community composition but it is poorly understood how toxic compounds influence physiology of single cells that may lay at the basis of loss of reproductive fitness. Here we analyze physiological disturbances of a variety of chemical pollutants at single cell level using the bacterium Pseudomonas fluorescens in an oligotrophic growth assay. As a proxy for physiological disturbance we measured changes in geometric mean ethidium bromide (EB) fluorescence intensities in subpopulations of live and dividing cells exposed or not exposed to different dosages of tetradecane, 4-chlorophenol, 2-chlorobiphenyl, naphthalene, benzene, mercury chloride, or water-dissolved oil fractions. Because ethidium bromide efflux is an energy-dependent process any disturbance in cellular energy generation is visible as an increased cytoplasmic fluorescence. Interestingly, all pollutants even at the lowest dosage of 1 nmol/mL culture produced significantly increased ethidium bromide fluorescence compared to nonexposed controls. Ethidium bromide fluorescence intensities increased upon pollutant exposure dosage up to a saturation level, and were weakly (r(2) = 0.3905) inversely correlated to the proportion of live cells at that time point in culture. Temporal increase in EB fluorescence of growing cells is indicative for toxic but reversible effects. Cells displaying high continued EB fluorescence levels experience constant and permanent damage, and no longer contribute to population growth. The procedure developed here using bacterial ethidium bromide efflux pump activity may be a useful complement to screen sublethal toxicity effects of chemicals.

Toxicity of chemical pollutants in aquatic environments is often addressed by assays that inquire reproductive inhibition of test microorganisms, such as algae or bacteria. Those tests, however, assess growth of populations as a whole via macroscopic methods such as culture turbidity or colony-forming units. Here we use flow cytometry to interrogate the fate of individual cells in low-density populations of the bacterium Pseudomonas fluorescens SV3 exposed or not under oligotrophic conditions to a number of common pollutants, some of which derive from oil contamination. Cells were stained at regular time intervals during the exposure assay with fluorescent dyes that detect membrane injury (i.e., live-dead assay). Reduction of population growth rates was observed upon toxicant insult and depended on the type of toxicant. Modeling and cell staining indicate that population growth rate decrease is a combined effect of an increased number of injured cells that may or may not multiply, and live cells dividing at normal growth rates. The oligotrophic assay concept presented here could be a useful complement for existing biomarker assays in compliance with new regulations on chemical effect studies or, more specifically, for judging recovery after exposure to fluctuating toxicant conditions.

Petroleum hydrocarbons are common contaminants in marine and freshwater aquatic habitats, often occurring as a result of oil spillage. Rapid and reliable on-site tools for measuring the bioavailable hydrocarbon fractions, i.e., those that are most likely to cause toxic effects or are available for biodegradation, would assist in assessing potential ecological damage and following the progress of cleanup operations. Here we examined the suitability of a set of different rapid bioassays (2-3 h) using bacteria expressing the LuxAB luciferase to measure the presence of short-chain linear alkanes, monoaromatic and polyaromatic compounds, biphenyls, and DNA-damaging agents in seawater after a laboratory-scale oil spill. Five independent spills of 20 mL of NSO-1 crude oil with 2 L of seawater (North Sea or Mediterranean Sea) were carried out in 5 L glass flasks for periods of up to 10 days. Bioassays readily detected ephemeral concentrations of short-chain alkanes and BTEX (i.e., benzene, toluene, ethylbenzene, and xylenes) in the seawater within minutes to hours after the spill, increasing to a maximum of up to 80 muM within 6-24 h, after which they decreased to low or undetectable levels. The strong decrease in short-chain alkanes and BTEX may have been due to their volatilization or biodegradation, which was supported by changes in the microbial community composition. Two- and three-ring PAHs appeared in the seawater phase after 24 h with a concentration up to 1 muM naphthalene equivalents and remained above 0.5 muM for the duration of the experiment. DNA-damage-sensitive bioreporters did not produce any signal with the oil-spilled aqueous-phase samples, whereas bioassays for (hydroxy)biphenyls showed occasional responses. Chemical analysis for alkanes and PAHs in contaminated seawater samples supported the bioassay data, but did not show the typical ephemeral peaks observed with the bioassays. We conclude that bacterium-based bioassays can be a suitable alternative for rapid on-site quantitative measurement of hydrocarbons in seawater.

Biocides are widely used for domestic hygiene, agricultural and industrial applications. Their widespread use has resulted in their introduction into the environment and raised concerns about potential deleterious effects on aquatic ecosystems. In this study, the toxicity of the biocides triclosan, penconazole and metalaxyl were evaluated with the freshwater bacterium Caulobacter crescentus and with a freshwater microbial community using a combination of single- and double-stain flow cytometric assays. Growth of C.  crescentus and the freshwater community were repressed by triclosan but not by penconazole or metalaxyl at concentrations up to 250 μM. The repressive effect of triclosan was dependent on culture conditions. Caulobacter crescentus was more sensitive to triclosan when grown with high glucose at high cell density than when grown directly in sterilized lake water at low cell density. This suggests that the use of conventional growth conditions may overestimate biocide toxicity. Additional experiments showed that the freshwater community was more sensitive to triclosan than C.  crescentus, with 10 nM of triclosan being sufficient to repress growth and change the phylogenetic composition of the community. These results demonstrate that isolate-based assays may underestimate biocide toxicity and highlight the importance of assessing toxicity directly on natural microbial communities. Because 10 nM of triclosan is within the range of concentrations observed in freshwater systems, these results also raise concerns about the risk of introducing triclosan into the environment.

Genomic islands are DNA elements acquired by horizontal gene transfer that are common to a large number of bacterial genomes, which can contribute specific adaptive functions, e.g. virulence, metabolic capacities or antibiotic resistances. Some genomic islands are still self-transferable and display an intricate life-style, reminiscent of both bacteriophages and conjugative plasmids. Here we studied the dynamical process of genomic island excision and intracellular reintegration using the integrative and conjugative element ICEclc from Pseudomonas knackmussii B13 as model. By using self-transfer of ICEclc from strain B13 to Pseudomonas putida and Cupriavidus necator as recipients, we show that ICEclc can target a number of different tRNA(Gly) genes in a bacterial genome, but only those which carry the GCC anticodon. Two conditional traps were designed for ICEclc based on the attR sequence, and we could show that ICEclc will insert with different frequencies in such traps producing brightly fluorescent cells. Starting from clonal primary transconjugants we demonstrate that ICEclc is excising and reintegrating at detectable frequencies, even in the absence of recipient. Recombination site analysis provided evidence to explain the characteristics of a larger number of genomic island insertions observed in a variety of strains, including Bordetella petri, Pseudomonas aeruginosa and Burkholderia.

Flow cytometry (FCM) is emerging as an important tool in environmental microbiology. Although flow cytometry applications have to date largely been restricted to certain specialized fields of microbiology, such as the bacterial cell cycle and marine phytoplankton communities, technical advances in instrumentation and methodology are leading to its increased popularity and extending its range of applications. Here we will focus on a number of recent flow cytometry developments important for addressing questions in environmental microbiology. These include (i) the study of microbial physiology under environmentally relevant conditions, (ii) new methods to identify active microbial populations and to isolate previously uncultured microorganisms, and (iii) the development of high-throughput autofluorescence bioreporter assays.

A yeast isolate revealing unique enzymatic activities and substrate-dependent polymorphism was obtained from autochthonous microflora of soil heavily polluted with oily slurries. By means of standard yeast identification procedures the strain was identified as Trichosporon cutaneum. Further molecular PCR product analyses of ribosomal DNA confirmed the identity of the isolate with the genus Trichosporon. As it grew on methanol as a sole carbon source, the strain appeared to be methylotrophic. Furthermore, it was also able to utilize formaldehyde. A multi-substrate growth potential was shown with several other carbon sources: glucose, glycerol, ethanol as well as petroleum derivatives and phenol. Optimum growth temperature was determined at 25 degrees C, and strong inhibition of growth at 37 degrees C together with the original soil habitat indicated lack of pathogenicity in warm-blooded animals and humans. The unusually high tolerance to xenobiotics such as diesel oil (>30 g/l), methanol (50 g/l), phenol (2 g/l) and formaldehyde (7.5 g/l) proved that the isolate was an extremophilic organism. With high-density cultures, formaldehyde was totally removed at initial concentrations up to 7.5 g/l within 24 h, which is the highest biodegradation capability ever reported. Partial biodegradation of methanol (13 g/l) and diesel fuel (20 g/l) was also observed. Enzymatic studies revealed atypical methylotrophic pathway reactions, lacking alcohol oxidase, as compared with the conventional methylotroph Hansenula polymorpha. However, the activities of glutathione-dependent formaldehyde dehydrogenase, formaldehyde reductase, formate dehydrogenase and unspecific aldehyde dehydrogenase(s) were present. An additional glutathione-dependent aldehyde dehydrogenase activity was also detected. Metabolic and biochemical characteristics of the isolated yeast open up new possibilities for environmental biotechnology. Some potential applications in soil bioremediation and wastewater decontamination are discussed.