OBJECTIVES: To evaluate the effect of short-term inhalational exposure to nanoparticles released during dental composite grinding on oxidative stress and antioxidant capacity markers. MATERIALS AND METHODS: Twenty-four healthy volunteers were examined before and after exposure in dental workshop. They spent 76.8 ± 0.7 min in the testing room during grinding of dental nanocomposites. The individual exposure to aerosol particles in each participant ́s breathing zones was monitored using a personal nanoparticle sampler (PENS). Exhaled breath condensate (EBC), blood, and urine samples were collected pre- and post-exposure to measure one oxidative stress marker, i.e., thiobarbituric acid reactive substances (TBARS), and two biomarkers of antioxidant capacity, i.e., ferric-reducing antioxidant power (FRAP) and reduced glutathione (GSH) by spectrophotometry. Spirometry and fractional exhaled nitric oxide (FeNO) were used to evaluate the effect of acute inhalational exposure. RESULTS: Mean mass of dental nanocomposite ground away was 0.88 ± 0.32 g. Average individual doses of respirable particles and nanoparticles measured by PENS were 380 ± 150 and 3.3 ± 1.3 μg, respectively. No significant increase of the post-exposure oxidative stress marker TBARS in EBC and plasma was seen. No decrease in antioxidant capacity biomarkers FRAP and GSH in EBC post-exposure was seen, either. Post-exposure, conjunctival hyperemia was seen in 62.5% volunteers; however, no impairment in spirometry or FeNO results was observed. No correlation of any biomarker measured with individual exposure was found, however, several correlations with interfering factors (age, body mass index, hypertension, dyslipidemia, and environmental pollution parameters) were seen. CONCLUSIONS: This study, using oxidative stress biomarker and antioxidant capacity biomarkers in biological fluids of volunteers during the grinding of dental nanocomposites did not prove a negative effect of this intense short-term exposure. However, further studies are needed to evaluate oxidative stress in long-term exposure of both stomatologists and patients and diverse populations with varying health statuses.
- MeSH
- antioxidancia analýza MeSH
- biologické markery * analýza MeSH
- dechové testy MeSH
- dospělí MeSH
- glutathion analýza MeSH
- inhalační expozice * škodlivé účinky analýza MeSH
- látky reagující s kyselinou thiobarbiturovou analýza MeSH
- lidé MeSH
- nanokompozity * chemie MeSH
- oxid dusnatý analýza metabolismus MeSH
- oxidační stres * MeSH
- pracovní expozice * analýza škodlivé účinky MeSH
- zubní lékaři MeSH
- zubní materiály MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Aim: Today, there is a lack of research studies concerning human acute exposure to nanoparticles (NPs). Our investigation aimed to simulate real-world acute inhalation exposure to NPs released during work with dental nanocomposites in a dental office or technician laboratory. Methods: Blood samples from female volunteers were processed before and after inhalation exposure. Transcriptomic mRNA and miRNA expression changes were analyzed. Results: We detected large interindividual variability, 90 significantly deregulated mRNAs, and 4 miRNAs when samples of participants before and after dental nanocomposite grinding were compared. Conclusion: The results suggest that inhaled dental NPs may present an occupational hazard to human health, as indicated by the changes in the processes related to oxidative stress, synthesis of eicosanoids, and cell division.
- MeSH
- dospělí MeSH
- inhalační expozice * škodlivé účinky MeSH
- lidé MeSH
- messenger RNA genetika MeSH
- mikro RNA * genetika MeSH
- nanočástice chemie MeSH
- nanokompozity * chemie MeSH
- oxidační stres účinky léků MeSH
- pracovní expozice škodlivé účinky MeSH
- transkriptom * účinky léků MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Colistimethate sodium (CMS) for treatment of lung infections in cystic fibrosis patient was transformed into a dry powder for inhalation by spray drying. Design of Experiment was applied for understanding the role of the spray-drying process parameters on the critical quality attributes of the CMS spray-dried (SD) powders and agglomerates thereof. Eleven experimental SD microparticle powders were constructed under different process conditions according to a central composite design. The SD microparticles were then agglomerated in soft pellets. Eleven physico-chemical characteristics of SD CMS microparticle powders or agglomerates thereof were selected as critical quality attributes. The yield of SD process was higher than 75%. The emitted fraction of agglomerates from RS01 inhaler was 75-84%, and the fine particle fraction (particles <5 µm) was between 58% and 62%. The quality attributes of CMS SD powders and respective agglomerates that were significantly influenced by spray-drying process parameters were residual solvent and drug content of the SD microparticles as well as bulk density and respirable dose of the agglomerates. These attributes were also affected by the combination of the process variables. The air aspiration rate was found as the most positively influential on drug and solvent content and respirable dose. The residual solvent content significantly influenced the powder bulk properties and aerodynamic behavior of the agglomerates, i.e. quality attributes that govern drug metering in the device and the particles lungs deposition. Agglomerates of CMS SD microparticles, in combination with RS01 DPI, showed satisfactory results in terms of dose emitted and fine particle fraction.
- MeSH
- aerosoly chemie farmakologie MeSH
- aplikace inhalační MeSH
- cystická fibróza farmakoterapie MeSH
- infekce farmakoterapie MeSH
- kolistin analogy a deriváty chemie MeSH
- lidé MeSH
- plíce účinky léků MeSH
- práškové inhalátory MeSH
- prášky, zásypy, pudry chemie farmakologie MeSH
- příprava léků metody MeSH
- rozpouštědla chemie MeSH
- velikost částic MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
The aim of this study was to determine particle size distributions (PSDs) generated by six pocket inhalers (2 × MDIs – metered dose inhalers and 4 × DPIs – dry powder inhalers) used in the treatment of asthma and chronic obstructive pulmonary disease (COPD). Two methods were compared – cascade impactor and time-of-flight online spectrometer. The results showed that the main modes positions of mass PSDs obtained by either of the methods were comparable. During the measurements of number PSDs by using of APS spectrometer, we measured bimodal distributions for MDI inhalers and monomodal ones for DPI inhalers. The differences of PSDs measured under ambient and respiratory tract conditions were minimal and did not influence the deposition area of inhalants. The results showed that the determination of the PSDs by online spectrometer is a suitable alternative to the traditional methods of measuring the particle size distributions of inhalation aerosol.
