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1.
J Plant Res ; 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38935314

ABSTRACT

Most studies of terrestrial bryophytes as natural substrates for photosynthetic microorganisms have been performed in the polar regions, where bryophytes are an important part of the ecosystem. As they remain green throughout the year, bryophytes may also be an ideal substrate for epiphytic organisms in temperate regions. The present study investigated the colonization potential and diversity of microalgae on selected plant species in riparian forest and spruce monoculture in a temperate region. It examines whether the presence of algae is related to substrate humidity, the micromorphology of gametophyte or the seasonal availability of substrate. The taxonomic diversity of algae was studied. Cyanobacteria and green algae were cultured on BG-11 agar medium, while diatoms were identified in permanent diatomaceous slides. The alpha- and beta-diversity indices were calculated, and the communities were compared using Bray-Curtis distances and multidimensional correspondence analyses. Our findings indicate that the largest number of alga species were diatoms; however, their presence was only observed in riparian forest and was associated with high humidity. Both aerophilic and freshwater taxa were noted, the latter carried by water from nearby aquatic ecosystem. Green algae were present in both phytocoenoses and humidity appears to have no substantial effect on the degree of colonization; their diversity was low and the group consisted of terrestrial taxa. In two bryophytes growing at the highest humidity, cyanobacteria were only identified in culture. The key factor influencing the degree of microalgae colonization was the humidity of the substrate, which was related to the distance from water.

2.
Int J Mol Sci ; 25(12)2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38928506

ABSTRACT

In the presented study, the effectiveness of a siloxane polyether (HOL7) coating on glass against microbiological colonization was assessed using microalgae as a key component of widespread aerial biofilms. The siloxane polyether was successfully synthesized by a hydrosilylation reaction in the presence of Karstedt's catalyst. The product structure was confirmed by NMR spectroscopy and GPC analysis. In addition, the thermal stability of HOL7 was studied by thermogravimetric measurement. Subsequently, the surfaces of glass plates were modified with the obtained organosilicon derivative. In the next step, a microalgal experiment was conducted. A mixture of four strains of algal taxa isolated from building materials was used for the experiment-Chlorodium saccharophilum PNK010, Klebsormidium flaccidum PNK013, Pseudostichococcus monallantoides PNK037, and Trebouxia aggregata PNK080. The choice of these algae followed from their wide occurrence in terrestrial environments. Application of an organofunctional siloxane compound on the glass reduced, more or less effectively, the photosynthetic activity of algal cells, depending on the concentration of the compound. Since the structure of the compound was not based on biocide-active agents, its effectiveness was associated with a reduction in water content in the cells.


Subject(s)
Microalgae , Siloxanes , Siloxanes/chemistry , Microalgae/chemistry , Biofilms/drug effects , Biofilms/growth & development , Ethers/chemistry , Ethers/pharmacology , Glass/chemistry , Photosynthesis
3.
J Clin Endocrinol Metab ; 109(2): e569-e578, 2024 01 18.
Article in English | MEDLINE | ID: mdl-37768152

ABSTRACT

CONTEXT: Discrepant data on the recurrence rate of differentiated thyroid cancer (DTC) are reported. OBJECTIVE: To evaluate the frequency and risk factors of true recurrence in DTC patients with excellent responses (ExR) to initial therapy. METHODS: A retrospective analysis of the 2302 consecutive DTC patients with ExR to primary therapy, treated during 24 years at single center. The percentage of recurrence and cumulative recurrence rate (CRR) were analyzed. Risk factors for recurrence for patients with papillary thyroid cancer (PTC) were investigated and methods for establishing a diagnosis of recurrence were evaluated. RESULTS: Of DTC patients, 32 (1.4%) experienced recurrence. PTC patients with recurrence were more likely to have younger age (P = .0182), larger tumor size (P = .0013), lymph node metastases (P = .0013), incomplete resection (P = .0446), higher ATA risk (P = .0002), and had more frequently been treated with 131I (P = .0203). CRRs at 5, 10, 15, 20, and 24 years after surgery were 1.2%, 1.9%, 2.5%, 2.9%, and 2.9%, respectively. The CRRs according to histological type were highest for poorly differentiated thyroid cancer (PDTC), lower for oncocytic (OTC) and follicular thyroid cancer (FTC), and lowest for PTC. Most recurrences occurred within the first 5 years of observation. The most effective method for detecting local recurrence was ultrasonography with fine needle aspiration cytology, and for distant metastases, 18F-FDG PET. CONCLUSION: True recurrence is rare in DTC patients. PTC patients with ExR to primary therapy and N0/Nx can be dismissed from oncological follow-up. Despite ExR to primary therapy, DTC patients with N1, and PDTC, OTC, FTC should remain under oncological follow-up.


Subject(s)
Adenocarcinoma, Follicular , Iodine Radioisotopes , Proline/analogs & derivatives , Thiocarbamates , Thyroid Neoplasms , Humans , Retrospective Studies , Thyroid Neoplasms/epidemiology , Thyroid Neoplasms/surgery , Thyroid Cancer, Papillary/epidemiology , Thyroid Cancer, Papillary/surgery , Neoplasm Recurrence, Local/pathology , Thyroidectomy
4.
Sci Rep ; 13(1): 22651, 2023 12 19.
Article in English | MEDLINE | ID: mdl-38114556

ABSTRACT

This research examines the biological treatment of undiluted vegetable waste digestate conducted in a bubble column photobioreactor. Initially, the bioreactor containing 3N-BBM medium was inoculated with Microglena sp., Tetradesmus obliquus, and Desmodesmus subspicatus mixture with a density of 1.0 × 104 cells/mL and the consortium was cultivated for 30 days. Then, the bioreactor was semi-continuously fed with liquid digestate with hydraulic retention time (HRT) of 30 days, and the treatment process was continued for the next 15 weeks. The change in the microalgal and cyanobacterial species domination was measured in regular intervals using cell counting with droplet method on a microscope slide. At the end of the experiment, Desmonostoc sp. cyanobacteria (identified with 16S ribosomal RNA genetical analysis) as well as Tetradesmus obliquus green algae along with Rhodanobacteraceae and Planococcaceae bacteria (determined with V3-V4 16sRNA metagenomic studies) dominated the microbial community in the photobioreactor. The experiment demonstrated high treatment efficiency, since nitrogen and soluble COD were removed by 89.3 ± 0.5% and 91.2 ± 1.6%, respectively, whereas for phosphates, 72.8 ± 2.1% removal rate was achieved.


Subject(s)
Chlorophyceae , Cyanobacteria , Microalgae , Photobioreactors , Waste Disposal, Fluid/methods , Vegetables , Anaerobiosis , Nitrogen , Biomass
5.
J Environ Manage ; 344: 118445, 2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37354587

ABSTRACT

A comparative study was carried out to assess the effect of two light sources on microalgae cultivation and the treatment of liquid digestate. The R1 photobioreactor operated with LED lightning allowed to achieve moderate nutrient removal rates whereas soluble COD (Chemical Oxygen Demand) was reduced in 90%. After switching this reactor into sunlight, the removal rate of phosphates increased to 66%. However, the greatest removal rate of both nutrients and sCOD of up to 93% was observed in the R2 photobioreactor operated only under sunlight. Microglena sp. was the dominant algae growing in the R1 reactor, and the main bacteria families detected were Chitinophagaceae, Sphingomonadaceae and Xanthobacteraceae. In contrast, Tetradesmus obliquus dominated in the R2 reactor and Rhodanobacteraceae, Chitinophagaceae and A4b were predominant bacteria in this run. Furthermore, much greater biomass productivity as well as overall biomass density was observed in the R2 photobioreactor cultivated exclusively with solar lightning.


Subject(s)
Microalgae , Sunlight , Humans , Lighting , Nutrients , Photobioreactors/microbiology , Biomass
6.
PLoS One ; 17(11): e0275665, 2022.
Article in English | MEDLINE | ID: mdl-36350818

ABSTRACT

Supported by the examination of specimens from the entire range and by the analysis of type specimens and the diagnosis of individual names, morphological and genetic studies of the Plagiothecium curvifolium complex resulted in the conclusion that this taxon should be recognized as four separate taxa. In addition to P. curvifolium s.str., there is a variety that is proposed as a new combination-P. curvifolium var. recurvum; resurrection of the forgotten P. decursivifolium; and the description of a new species-P. imbricatum. The features that distinguish individual taxa focus primarily on: plant size; arrangement of leaves on the stem; the symmetry, dimensions, shape, concavity and folding of leaves; cell length; serration of the leaf apex; the shape of the decurrencies; the length of the sporophyte and the shape of the operculum. For all described taxa, the distribution, ecological preferences, key to their identification and detailed photographic documentation have been provided.


Subject(s)
Bryopsida , Phylogeny
7.
Molecules ; 27(20)2022 Oct 13.
Article in English | MEDLINE | ID: mdl-36296449

ABSTRACT

The ability of aquatic microalgae to treat the liquid digestate obtained from the anaerobic digestion of plant waste was investigated. Microalgae were isolated from natural environment for a laboratory-scale cultivation and were then used to remove nutrients and organic contaminants from the liquid digestate. It was shown that the microalgae consortia (Tetradesmus obliquus, Microglena sp., Desmodesmus subspicatus) could reduce nitrogen, phosphates, and total COD by up to 70%, 57%, and 95%, respectively. A new algae genus Microglena was isolated, which in a consortium with Tetradesmus obliquus and Desmodesmus subspicatus exhibited a high efficiency in the removal of both organic contaminants and nutrients from the liquid fraction of digestate.


Subject(s)
Chlorophyta , Microalgae , Ponds , Biomass , Nitrogen , Phosphates , Wastewater
8.
Article in English | MEDLINE | ID: mdl-35742239

ABSTRACT

Algal blooms are an emerging problem. The massive development of phytoplankton is driven partly by the anthropogenic eutrophication of aquatic ecosystems and the expansion of toxic cyanobacteria in planktonic communities in temperate climate zones by the continual increase in global temperature. Cyanobacterial harmful algal blooms (CyanoHABs) not only disturb the ecological balance of the ecosystem, but they also prevent the use of waterbodies by humans. This study examines the cause of an unusual, persistent bloom in a recreational, flow-through reservoir; the findings emphasize the role played by the river supplying the reservoir in the formation of its massive cyanobacterial bloom. Comprehensive ecosystem-based environmental studies were performed, including climate change investigation, hydrochemical analysis, and bio-assessment of the ecological state of the river/reservoir, together with monitoring the cyanobacteria content of phytoplankton. Our findings show that the persistent and dominant biomass of Microcystis was related to the N/P ratio, while the presence of Aphanizomenon and Dolichospermum was associated with the high-temperature end electric conductivity of water. Together with the increase in global temperature, the massive and persistent cyanobacterial bloom appears to be maintained by the inflow of biogenic compounds carried by the river and the high electric conductivity of water. Even at the beginning of the phenomenon, the reservoir water already contained cyanobacterial toxins, which excluded its recreational use for about half the year.


Subject(s)
Cyanobacteria , Ecosystem , Biodiversity , Eutrophication , Harmful Algal Bloom , Humans , Lakes , Phytoplankton , Temperature , Water
9.
PhytoKeys ; 194: 63-73, 2022.
Article in English | MEDLINE | ID: mdl-35586326

ABSTRACT

Plagiotheciumtalbotii sp. nov. is described from Attu Island, Alaska, U.S.A. The newly-described species is not similar in appearance to any Northern Hemisphere species; only the habit is similar to P.platyphyllum. However, it not only occupies a different habitat than that species, but genetically and morphologically, it is clearly distinct from it. The results of DNA sequencing, a detailed description of the morphological features, illustrations, ecological preferences and currently known geographical distribution of P.talbotii are presented. The most important distinguishing morphological features of this species are: the size of the plant; dimensions and symmetry of the leaves; dimensions of cells and their areolation; entire leaf apex; and long decurrencies with some inflated cells. Additionally, we propose to place P.talbotii in section Plagiothecium, which is confirmed by genetic analysis and morphological features.

10.
Sci Total Environ ; 802: 149856, 2022 Jan 01.
Article in English | MEDLINE | ID: mdl-34454144

ABSTRACT

The gradual degradation of technical materials by bacteria, cyanobacteria and fungi, is of great economic and social significance. In temperate climates, microbial colonization is associated with phototrophic eukaryotes, predominantly aerial green algae. However, these phototrophs are able to colonize most substrates in all terrestrial environments, regardless he geographical area. As little is known of the life processes of green algae, it is widely believed that their impact on materials is purely aesthetic. Most studies on the deterioration of building materials examine both algae and cyanobacteria and propose various methods, mainly conservation practices, to halt the causes and effects of algal colonization. However, to fully comprehend the phenomenon of biodeterioration by green algae, it is essential to understand both the causes and effects of their activities, as their life processes have considerable influence on changes of technical state of building materials. Aerophytic green algae possess various cellular adaptations and life mechanisms to survive and successfully develop in the harsh terrestrial environment. In response to desiccation, UV radiation and high/low temperature fluctuation they form endo- and epilithic biofilms, produce various protective biomolecules and extracellular matrices, and change the volume of cells. Due to their adaptation mechanisms and wide ecological tolerance, green algae undoubtedly have a high potential to accelerate the degradation of building materials. This article reviews the current state of knowledge regarding the mechanisms of biodeterioration, examines the role played by green algae as a result of their adaptation to a terrestrial environment, presents methods that can be used to prevent the development of green algal biofilms and indicate future prospects in the assessment of algal deterioration studies.


Subject(s)
Chlorophyta , Cyanobacteria , Biofilms , Construction Materials , Eukaryota
11.
PeerJ ; 9: e12457, 2021.
Article in English | MEDLINE | ID: mdl-34900419

ABSTRACT

Transformation of river and stream channels disrupts their natural ecological cycles and interrupts the continuum of their ecosystems. Changes in natural hydromorphological conditions transform lotic communities into those atypical of flowing waters, resulting in bioassessment procedures yielding incorrect results. This study shows how hydromorphological transformations of ecosystems affect the ecological status bioassessment results by disturbing diatom communities typical for rivers. Moreover, the article presents a new biological assessment procedure for urban transformed rivers including the verification of the community structure based on autecology and quantity of species. The ecological status of the ecosystem was assessed using benthic diatom assemblages and supported with results of hydrochemical analysis. The structure of the assemblages and their relationships between individual sampling sites were clarified by shade plot and multivariate data analyses. The analysis of dominant species vitality at sampling sites and their autecology gave the foundation for modification of taxa data matrix and recalculation the diatom indices. Biological assessment showed that one of the artificial ponds constructed at the stream channel was characterized by good ecological status, and its presence strongly affected the state of the downstream ecosystem following the development of a unique assemblage of diatoms that prefer oligosaprobic and oligotrophic waters. The presence of these species was also noted in the downstream sections, but most of the cells were dead. As the indicator values of these taxa are high, their presence artificially increased the ecological status of the stream, resulting in the hydrochemical assessment not being in line with the bioassessment. Therefore, a new procedure was adopted in which non-characteristic taxa for the downstream sections were excluded from analysis. This approach corrected the results of bioassessment characterizing the ecological status of the stream as poor along its entire course, with the exception of this unique pond. For hydromorphologically transformed streams and rivers with disturbed channel continuity, the correct result of an incorrect diatom-based bioassessment may be retrieved after excluding species unusual for the type of ecosystem from the studied assemblages, i.e., the species which are unable to reproduce in that area and are only carried into it by the water flow. Assessment of the ecological status of aquatic ecosystems based on biotic factors is an essential tool of aquatic ecosystems monitoring in many countries. This type of assessment requires a multifaceted approach, in particular, to identify factors that may disrupt this assessment. Standardization of biomonitoring methods is an important step in correct assessment; thus, the findings of this paper will be useful in routine biomonitoring around the world.

12.
PhytoKeys ; 184: 127-138, 2021.
Article in English | MEDLINE | ID: mdl-34785976

ABSTRACT

Plagiotheciumschofieldii sp. nov. is described from the Aleutian Islands, Alaska, U.S.A. Some morphological features of this species correspond to P.lamprostachys (Southern Hemisphere species); however, Plagiotheciumschofieldii is genetically and morphologically different from this and other common Northern Hemisphere species e.g., P.denticulatum, P.platyphyllum, or P.ruthei. The most important distinguishing morphological features differentiating this species are: the arrangement of the leaves on the stem; dimensions, concavity and symmetry of the leaves; dimensions of cells and their areolation; orientation of capsules. Additionally, due to the strong concavity of the leaves, they are very often badly damaged under the microscope. We present the results of DNA research of the analyzed samples, and a detailed description of the morphological features. The new species is illustrated, and its ecological preferences and currently known geographical distribution are presented. Additionally, the authors propose to add this species to Plagiothecium section, which is confirmed by morphological features and genetic analysis.

13.
Food Chem Toxicol ; 154: 112316, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34089800

ABSTRACT

Mitochondria are among the first responders to various stress factors that challenge cell and tissue homeostasis. Various plant alkaloids have been investigated for their capacity to modulate mitochondrial activities. In this study, we used isolated mitochondria from mouse brain and liver tissues to assess nicotine, anatabine and anabasine, three alkaloids found in tobacco plant, for potential modulatory activity on mitochondrial bioenergetics parameters. All alkaloids decreased basal oxygen consumption of mouse brain mitochondria in a dose-dependent manner without any effect on the ADP-stimulated respiration. None of the alkaloids, at 1 nM or 1.25 µM concentrations, influenced the maximal rate of swelling of brain mitochondria. In contrast to brain mitochondria, 1.25 µM anatabine, anabasine and nicotine increased maximal rate of swelling of liver mitochondria suggesting a toxic effect. Only at 1 mM concentration, anatabine slowed down the maximal rate of Ca2+-induced swelling and increased the time needed to reach the maximal rate of swelling. The observed mitochondrial bioenergetic effects are probably mediated through a pathway independent of nicotinic acetylcholine receptors, as quantitative proteomic analysis could not confirm their expression in pure mitochondrial fractions isolated from mouse brain tissue.


Subject(s)
Alkaloids/toxicity , Mitochondria/drug effects , Plants/chemistry , Animals , Brain/drug effects , Brain/metabolism , Energy Metabolism/drug effects , Membrane Potential, Mitochondrial/drug effects , Mice , Mitochondria/metabolism , Proteomics , Receptors, Nicotinic/metabolism
14.
J Phys Chem Lett ; 11(16): 6914-6920, 2020 Aug 20.
Article in English | MEDLINE | ID: mdl-32787203

ABSTRACT

Metabolic reactions in living cells are limited by diffusion of reagents in the cytoplasm. Any attempt to quantify the kinetics of biochemical reactions in the cytosol should be preceded by careful measurements of the physical properties of the cellular interior. The cytoplasm is a complex, crowded fluid characterized by effective viscosity dependent on its structure at a nanoscopic length scale. In this work, we present and validate the model describing the cytoplasmic nanoviscosity, based on measurements in seven human cell lines, for nanoprobes ranging in diameters from 1 to 150 nm. Irrespective of cell line origin (epithelial-mesenchymal, cancerous-noncancerous, male-female, young-adult), we obtained a similar dependence of the viscosity on the size of the nanoprobes, with characteristic length-scales of 20 ± 11 nm (hydrodynamic radii of major crowders in the cytoplasm) and 4.6 ± 0.7 nm (radii of intercrowder gaps). Moreover, we revealed that the cytoplasm behaves as a liquid for length scales smaller than 100 nm and as a physical gel for larger length scales.


Subject(s)
Cytoplasm/chemistry , Cell Line, Tumor , Cytoplasm/ultrastructure , Dextrans/chemistry , Diffusion , Fluoresceins/chemistry , Fluorescent Dyes/chemistry , Humans , Nanoparticles/chemistry , Particle Size , Rhodamines/chemistry , Silicon Dioxide/chemistry , Viscosity
15.
Postepy Dermatol Alergol ; 37(1): 73-80, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32467688

ABSTRACT

INTRODUCTION: Chronic autoimmune urticaria (CAU) lasts over 6 weeks and is characterized by circulating IgE autoantibodies or IgG against IgE or IgE receptor. AIM: To assess the clinical, laboratory and histological effects of 4-week levocetirizine and montelukast therapy in patients suffering from CAU. MATERIAL AND METHODS: Of 296 tested patients with chronic urticaria 40 had a positive ASST test. Only 17 (16 female/1 male; medium age: 44 years) fulfilled all study inclusion/exclusion criteria. The study was designed as an open, randomized trial with two arms: levocetirizine or montelukast treatment for 4 weeks following a 2-week wash-out period. All participants completed urticaria activity score (UAS) and visual analogue scale (VAS) questionnaires before and after both therapies. Blood samples and skin bioptats were obtained before and after treatment to evaluate COX-1 and COX-2 serum concentrations and skin expression. RESULTS: Clinical response to therapy measured with the UAS and VAS was better in the levocetirizine group. Both drugs caused a significant decrease in COX-1 and COX-2 serum level. COX-1 and COX-2 expression in epidermal and dermal inflammatory infiltration did not change significantly in either study group, but a significant decrease of COX-1 expression was observed when the groups were combined for analysis, and the decrease in COX-2 expression in the epidermis was of borderline significance. CONCLUSIONS: The effectiveness of levocetirizine and montelukast in treating CAU may be partly related to the reduction of COX-1 and COX-2 serum level and tissue expression, but further studies on a larger group of patients are needed to support this observation.

16.
PLoS One ; 15(3): e0230237, 2020.
Article in English | MEDLINE | ID: mdl-32160254

ABSTRACT

Plagiothecium longisetum was described by Lindberg in 1872, based on Maximowicz materials from Japan. In the 1970s, this species was synonymized with P. nemorale. However, a polyphasic approach applied to the investigation of the P. nemorale sensu lato showed a clear separation between the specimens of former P. longisetum and the type of P. nemorale. Morphological features and molecular analyses provide evidence that those two groups are distinct, as well as allowed to describe the new species. The results are strongly supported by the statistical analyses of morphometric features and phylogenetic analyses based on concatenated nuclear and chloroplast DNA markers. The maximum likelihood (ML) and Bayesian inference (BI) analyses of ITS, rps4 and rpl16 regions place both species outside the P. nemorale group. The distinctions between individual species, reflected by the morphological features-easy to observe-and the molecular data, provide a scientific foundation for the resurrection of P. longisetum Lindb. and establishment of a new species-P. angusticellum sp. nov.


Subject(s)
Bryopsida/genetics , Bryopsida/metabolism , Phylogeny , Sequence Analysis, DNA , Species Specificity
17.
J Bioenerg Biomembr ; 51(4): 259-276, 2019 08.
Article in English | MEDLINE | ID: mdl-31197632

ABSTRACT

Mitochondria are multifunctional and dynamic organelles deeply integrated into cellular physiology and metabolism. Disturbances in mitochondrial function are involved in several disorders such as neurodegeneration, cardiovascular diseases, metabolic diseases, and also in the aging process. Nicotine is a natural alkaloid present in the tobacco plant which has been well studied as a constituent of cigarette smoke. It has also been reported to influence mitochondrial function both in vitro and in vivo. This review presents a comprehensive overview of the present knowledge of nicotine action on mitochondrial function. Observed effects of nicotine exposure on the mitochondrial respiratory chain, oxidative stress, calcium homeostasis, mitochondrial dynamics, biogenesis, and mitophagy are discussed, considering the context of the experimental design. The potential action of nicotine on cellular adaptation and cell survival is also examined through its interaction with mitochondria. Although a large number of studies have demonstrated the impact of nicotine on various mitochondrial activities, elucidating its mechanism of action requires further investigation.


Subject(s)
Cigarette Smoking/metabolism , Mitochondria/metabolism , Nicotine , Animals , Calcium/metabolism , Cigarette Smoking/pathology , Electron Transport Chain Complex Proteins/metabolism , Humans , Mitochondria/pathology , Mitophagy/drug effects , Nicotine/adverse effects , Nicotine/pharmacokinetics , Oxidative Stress/drug effects
18.
Molecules ; 24(10)2019 May 21.
Article in English | MEDLINE | ID: mdl-31117281

ABSTRACT

Candida biofilm structure is particularly difficult to eradicate, since biofilm is much more resistant to antifungal agents than planktonic cells. In this context, a more effective strategy seems to be the prevention of biofilm formation than its eradication. The aim of the study was to examine whether the process of initial colonization of materials (glass, polyethylene terephthalate, polypropylene) by food-borne Candida sp. can be impeded by clove and thyme essential oils, used at their minimal inhibitory concentrations. In the presence of clove oil, 68.4-84.2% of the yeast tested showed a statistically significant reduction in biofilm formation, depending on the material. After treatment with thyme oil, statistically significant decrease in biofilm cell numbers was observed for 63.2-73.7% of yeasts. Confocal laser scanning microscopy showed diverse compounds of clove and thyme oils that were disparately located in C. albicans cell, on a cell wall and a cell membrane, in cytoplasm, and in vacuoles, depicting the multidirectional action of essential oils. However, essential oils that were used in sub-inhibitory concentration were sequestrated in the yeast vacuoles, which indicate the activation of Candida defense mechanisms by cell detoxification. Clove and thyme essential oils due to their anti-biofilm activity can be efficiently used in the prevention of the tested abiotic surfaces colonization by Candida sp.


Subject(s)
Biofilms/drug effects , Oils, Volatile/pharmacology , Syzygium/chemistry , Thymus Plant/chemistry , Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Candida albicans/drug effects , Candida albicans/pathogenicity , Cell Wall/drug effects , Clove Oil/chemistry , Clove Oil/pharmacology , Microbial Sensitivity Tests , Oils, Volatile/chemistry , Plant Oils/chemistry , Plant Oils/pharmacology
19.
Sci Rep ; 9(1): 5906, 2019 04 11.
Article in English | MEDLINE | ID: mdl-30976093

ABSTRACT

Biochemistry in living cells is an emerging field of science. Current quantitative bioassays are performed ex vivo, thus equilibrium constants and reaction rates of reactions occurring in human cells are still unknown. To address this issue, we present a non-invasive method to quantitatively characterize interactions (equilibrium constants, KD) directly within the cytosol of living cells. We reveal that cytosolic hydrodynamic drag depends exponentially on a probe's size, and provide a model for its determination for different protein sizes (1-70 nm). We analysed oligomerization of dynamin-related protein 1 (Drp1, wild type and mutants: K668E, G363D, C505A) in HeLa cells. We detected the coexistence of wt-Drp1 dimers and tetramers in cytosol, and determined that KD for tetramers was 0.7 ± 0.5 µM. Drp1 kinetics was modelled by independent simulations, giving computational results which matched experimental data. This robust method can be applied to in vivo determination of KD for other protein-protein complexes, or drug-target interactions.


Subject(s)
Cytosol/metabolism , Dynamins/chemistry , Mitochondria/metabolism , Mitochondrial Membranes/metabolism , Protein Multimerization , Dynamins/genetics , Dynamins/metabolism , Humans , Mitochondrial Dynamics , Models, Molecular , Mutation , Protein Binding , Protein Conformation , Protein Transport
20.
Biofouling ; 35(3): 284-298, 2019 03.
Article in English | MEDLINE | ID: mdl-31014110

ABSTRACT

The scientific multistep approach described herein is a result of two years of research into a control method against microbial fouling and biodeterioration of historic building materials by phototrophs. A series of tests were conducted to select the best antifouling agent for eliminating 'green' coatings and protecting surfaces against biofouling. Of the seven active compounds, two with the best penetration abilities were subjected to a photosynthetic activity inhibition test using confocal microscopy. Of the two, a quaternary ammonium salt (QAC) - didecyldimethylammonium chloride (DDAC) - was found to be the most effective. Ten biocides containing QACs at different concentrations were then tested against 'green' coatings on wood, brick and plaster, with the best four being selected for further research in model conditions. As a result, biocides containing >14% (v v-1) DDAC were found to be successful antifouling agents for protecting historical materials against biodeterioration by phototrophs.


Subject(s)
Biofouling , Phosphorus/pharmacology , Air , Disinfectants/analysis , Quaternary Ammonium Compounds/analysis , Wood
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