Ondrej Machaczka

Dr. Ondrej Machaczka

Centre for Epidemiological Research, Faculty of Medicine, University of Ostrava, 703 00 Ostrava, Czech Republic
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Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 March 2022 in Atmosphere
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Journal Article
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JMJiri Michalik
Jiri Michalik
OMOndrej Machaczka
Ondrej Machaczka
VJVitezslav Jirik
Vitezslav Jirik
THTomas Heryan
Tomas Heryan
VJVladimir Janout
Vladimir Janout
Only a few researchers have addressed the issue of lifetime exposure related to air pollutant concentration. This study aims to develop a methodology to obtain the most reliable estimates of historical concentrations of air pollutants, which would be further applied to the long-term exposure evaluation. In particular, PM10, PM2.5, NO2, SO2, benzene, and B(a)P concentrations have been obtained. Data of monitored concentrations, model calculations, and subsequent implementation of several corrections based on previous work on temporal and spatial correlations of these substances in the air have been deployed. This work makes an original contribution to the field of meteorology and epidemiology because of this innovative technique to estimate the most reliable historical concentrations of air pollutants. The novelty of our work lies in the additional implications of this study because historical concentration data serve as input data for the construction of epidemiological associations. The approach is based primarily on the availability of monitoring results of air pollutants.

23 September 2019 in Biomedical Papers
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MHMiroslav Homza
Miroslav Homza
OMOndrej Machaczka
Ondrej Machaczka
MPMartin Porzer
Martin Porzer
MKMilan Kozak
Milan Kozak
JPJiří Plášek
Jiří Plášek
DSDavid Sipula
David Sipula
Ankle brachial index (ABI) is the principal screening method for peripheral arterial disease (PAD). In this study, we compare various types of Doppler-derived and oscillometric ABIs with results obtained through duplex ultrasonography. 62 patients were enrolled in the study. For each limb, blood pressures for both ankle arteries and the arm were measured using Doppler and an automated oscillometric device. Duplex ultrasound was performed for all limbs and occlusions >50% were considered PAD-positive. ABI was calculated using both higher (HABP) and lower (LABP) arterial blood pressure on the individual limbs and the ability to predict duplex-detected stenoses was evaluated. LABP calculation provided results superior to the guideline-recommended HABP. Considering patients with ABI >1.4 or measurement failure as PAD-positive further enhanced the test parameters. The higher ABI cut-off of 1.0 resulted in somewhat better sensitivities (max 92%) and negative predictive values (max 87%) at the expense of a substantial increase in the number of false positives. Oscillometric method yielded poor sensitivities but very good specificities (max 94%) and positive predictive values (max 90%). Doppler-based LABP provides better results than the guideline-recommended HABP in diabetic patients, nevertheless even this method is not perfect. Increasing the cut-off value to 1.0 in these patients does not bring a substantial improvement of the test performance. Patients with high ABI should be automatically considered PAD-positive and referred for further investigation using imaging techniques.

2 July 2024 in Environmental Sciences Europe
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VJVítězslav Jiřík
Vítězslav Jiřík
OMOndrej Machaczka
Ondrej Machaczka
PRPetra Riedlová
Petra Riedlová
DKDagmar Kramná
Dagmar Kramná
GSGrzegorz Siemiatkowski
Grzegorz Siemiatkowski
Pavel RossnerPavel Rossner
Pavel Rossner
Background: Air pollution is associated with adverse health effects, especially on the respiratory and cardiovascular systems, but according to recent research, even in cognitive health, metabolic, and immune systems. The objective was to analyse the effect of long-term exposure to air pollution on selected immune system parameters, 8-isoprostane a parameter of oxidative stress, and alpha-1-antitrypsin a protease inhibitor. Methods: The number of 381 probands aged 35–65 from two differently polluted regions was included. Lifetime exposures to PM10, PM2.5, NO2, B(a)P, and benzene for each proband were calculated based on historical pollutant concentrations observed. The selected blood parameters were analysed in relation to independent variables (air pollutants, socioeconomic factors, etc.) using multiple regression. Possible covariates were determined. In its end, the study was conceived as a case–control study, and the odds ratio was quantified, expressing the strength of the association of the monitored parameters with the region. Results: The average lifetime exposures to air pollution were significantly different between the two regions. Significant effects of the region were observed on IgM, IL-6, 8-isoprostane, and alpha-1-antitrypsin levels. The strongest positive association was observed between 8-isoprostane levels and benzene, PM2.5, PM10 and B(a)P. Odds ratio was 3.21 (95%CI 1.61–6.38). A significant negative association between all pollutants and IgM levels was observed even with covariate adjustment. Odds ratio was 1.80 (95%CI 1.15–2.82). A significant negative association between the alpha-1-antitrypsin levels and PM10, PM2.5, and benzene was found, independent of smoking as a covariate factor. Odds ratio was 1.77 (95%CI 1.09–2.87). In the case of IL-6, a significant effect of especially sleep as a covariate was observed. After covariates adjustment, a significant positive association between the IL-6 levels and PM10 and benzene was only observed. The odds ratio was 1.95 (95%CI 1.28–2.97). Conclusions: The study confirmed that long-term exposure to air pollutants is associated with reduced levels of the protease inhibitor alpha-1-antitrypsin and decreased immune system performance by IgM. Furthermore, long-term exposure to air pollutants was associated with increased oxidative stress in humans, measured by 8-isoprostane levels. Residents who live in an industrial, environmentally polluted region showed elevated levels of IL-6.

31 May 2018 in Česká a slovenská neurologie a neurochirurgie
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JJJana Janoutová
Jana Janoutová
PAPetr Ambroz
Petr Ambroz
MKMartina Kovalová
Martina Kovalová
OMOndrej Machaczka
Ondrej Machaczka
KNKateřina Němeček
Kateřina Němeček
VJVladimír Janout
Vladimír Janout

OMOndrej Machaczka
Ondrej Machaczka
VJVitezslav Jirik
Vitezslav Jirik
VBViera Brezinova
Viera Brezinova
AVAdela Vrtkova
Adela Vrtkova
HMHana Miturova
Hana Miturova
RSRadim J. Sram
Radim J. Sram
The health impacts of suspended particulate matter (SPM) are significantly associated with size—the smaller the aerosol particles, the stronger the biological effect. Quantitative evaluation of fine and ultrafine particles (FP and UFP) is, therefore, an integral part of ongoing epidemiological studies. The mass concentrations of SPM fractions (especially PM2.5, PM1.0, PM0.25) were measured in an industrial area using cascade personal samplers and a gravimetric method, and their mass ratio was determined. The results of PM2.5, PM1.0 were also compared with the reference measurement at stationary stations. The mean ratios PM2.5/SPM, PM1.0/SPM, and PM1.0/PM2.5 were 0.76, 0.65, and 0.86, respectively. Surprisingly, a mass dominance of UFP with an aerodynamic diameter <0.25 μm (PM0.25) was found with mean ratios of 0.43, 0.57, 0.67 in SPM, PM2.5 and PM1.0. The method used showed satisfactory agreement in comparison with reference measurements. The respirable fraction may consist predominantly of UFP. Despite the measures currently being taken to improve air quality, the most biologically efficient UFP can escape and remain in the air. UFP are currently determined primarily as particle number as opposed to the mass concentration used for conventional fractions. This complicates their mutual comparison and determination of individual fraction ratios.

1 October 2024 in Journal of Otology
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Open access
NGNikol Gottfriedová
Nikol Gottfriedová
MKMartina Kovalová
Martina Kovalová
EMEva Mrázková
Eva Mrázková
OMOndrej Machaczka
Ondrej Machaczka
VKVeronika Koutná
Veronika Koutná
JJJana Janoutová
Jana Janoutová
Background: Over 55 million people worldwide are living with dementia. The rate of cognitive decline increases with age, and loss of senses may be a contributing factor. Objectives: This study aimed to analyze hearing, olfactory function, and color vision in patients with dementia. Materials and methods: The sample comprised 40 patients with dementia and 37 cognitively normal controls aged 41-85 years. All participants underwent conventional pure-tone audiometry and a screening version of the Hearing Handicap Inventory for Adults, the Odorized Markers Test of olfactory function and the Ishihara color vision test. The effects of comorbidities and lifestyle factors were also assessed. Results: Patients with dementia had significantly worse hearing at almost all frequencies tested and significantly greater olfactory impairment than cognitively normal controls. Color vision impairment was found in less than 8% of the sample, with no significant difference between the groups. Impairment of two senses (hearing and olfaction) was significantly more common in patients with dementia than in controls. Conclusion: Individuals with dementia were found to have sensory decline, namely hearing and olfactory impairment. Color vision was rarely impaired in the sample. Participants with dementia tended to have more multisensory impairments than controls.