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In this study, we report on a novel heteroplasmic pathogenic variant in mitochondrial DNA (mtDNA). The studied patient had myoclonus, epilepsy, muscle weakness, and hearing impairment and harbored a heteroplasmic m.8315A>C variant in the MTTK gene with a mutation load ranging from 71% to >96% in tested tissues. In muscle mitochondria, markedly decreased activities of respiratory chain complex I + III and complex IV were observed together with mildly reduced amounts of complex I and complex V (with the detection of V*- and free F1-subcomplexes) and a diminished level of complex IV holoenzyme. This pattern was previously seen in other MTTK pathogenic variants. The novel variant was not present in internal and publicly available control databases. Our report further expands the spectrum of MTTK variants associated with mitochondrial encephalopathies in adults. [ABSTRACT FROM AUTHOR]

Endothelial cell (EC) glycocalyx (GLX) comprise a multicomponent layer of proteoglycans and glycoproteins. Alteration of its integrity contributes to chronic vascular inflammation and leads to the development of cardiovascular diseases. Myeloperoxidase (MPO), a highly abundant enzyme released by polymorphonuclear neutrophils, binds to the GLX and deleteriously affects vascular EC functions. The focus of this study was to elucidate the mechanisms of MPO-mediated alteration of GLX molecules, and to unravel subsequent changes in endothelial integrity and function. MPO binding to GLX of human ECs and subsequent internalization was mediated by cell surface heparan sulfate chains. Moreover, interaction of MPO, which is carrying a cationic charge, with anionic glycosaminoglycans (GAGs) resulted in reduction of their relative charge. By means of micro-viscometry and atomic force microscopy, we disclosed that MPO can crosslink GAG chains. MPO-dependent modulation of GLX structure was further supported by alteration of wheat germ agglutinin staining. Increased expression of ICAM-1 documented endothelial cell activation by both catalytically active and also inactive MPO. Furthermore, MPO increased vascular permeability connected with reorganization of intracellular junctions, however, this was dependent on MPO's catalytic activity. Novel proteins interacting with MPO during transcytosis were identified by proteomic analysis. Altogether, these findings provide evidence that MPO through interaction with GAGs modulates overall charge of the GLX, causing modification of its structure and thus affecting EC function. Importantly, our results also suggest a number of proteins interacting with MPO that possess a variety of cellular localizations and functions. Image 1 • MPO binds to the glycocalyx through a charge interaction with glycosaminoglycans. • The interaction between cationic MPO and glycocalyx induces collapse of the structural integrity of the glycocalyx. • MPO mediates alteration in endothelial integrity and function. • Binding partners of MPO during transcytosis are cytoskeletal proteins and proteins involved in cell signaling and regulation. [ABSTRACT FROM AUTHOR]

Abstract: Background: Myeloperoxidase (MPO) is an abundant hemoprotein expressed by neutrophil granulocytes that is recognized to play an important role in the development of vascular diseases. Upon degranulation from circulating neutrophil granulocytes, MPO binds to the surface of endothelial cells in an electrostatic-dependent manner and undergoes transcytotic migration to the underlying extracellular matrix (ECM). However, the mechanisms governing the binding of MPO to subendothelial ECM proteins, and whether this binding modulates its enzymatic functions are not well understood. Methods: We investigated MPO binding to ECM derived from aortic endothelial cells, aortic smooth muscle cells, and fibroblasts, and to purified ECM proteins, and the modulation of these associations by glycosaminoglycans. The oxidizing and chlorinating potential of MPO upon binding to ECM proteins was tested. Results: MPO binds to the ECM proteins collagen IV and fibronectin, and this association is enhanced by the pre-incubation of these proteins with glycosaminoglycans. Correspondingly, an excess of glycosaminoglycans in solution during incubation inhibits the binding of MPO to collagen IV and fibronectin. These observations were confirmed with cell-derived ECM. The oxidizing and chlorinating potential of MPO was preserved upon binding to collagen IV and fibronectin; even the potentiation of MPO activity in the presence of collagen IV and fibronectin was observed. Conclusions: Collectively, the data reveal that MPO binds to ECM proteins on the basis of electrostatic interactions, and MPO chlorinating and oxidizing activity is potentiated upon association with these proteins. General significance: Our findings provide new insights into the molecular mechanisms underlying the interaction of MPO with ECM proteins. [Copyright &y& Elsevier]

Triclosan and Triclocarban, preservatives widely used in cosmetics and other consumer products, underwent evaluation using a battery of new-approach methodologies in vitro (NAMs). Specifically, the Microplate Ames Test (MPF™ Test, Xenometrix, Allschwil, Switzerland) was employed to assess mutagenicity, the Comet assay in vitro on the HaCat cell line and the Mammalian Chromosome Aberration Test were utilized to evaluate genotoxicity, and the XenoScreen® YES/YAS assay was applied to investigate endocrine disruption. The chemicals did not exhibit any positive responses for mutagenicity. However, the mammalian chromosome aberration test identified both chemicals as being positive for genotoxicity at 10 µg/mL. In the Comet assay, the percentage of DNA in the tail significantly increased in a concentration-dependent manner (at 5 and 10 µg/mL for Triclosan, at 2.5, 5, and 10 µg/mL for Triclocarban). The positive response depended on the increasing concentration and the duration of exposure. Triclosan, but not Triclocarban in any of the endocrine assays performed, indicated a potential for endocrine activity in the anti-estrogenic and anti-androgenic assays. The positive in vitro results detected were obtained for concentrations relevant to final products. The alarming findings obtained with the use of new-approach methodologies (NAMs) justify the current precautionary regulatory approach, limiting the use of these preservatives. [ABSTRACT FROM AUTHOR]

The recent description of biallelic DNAJC30 variants in Leber hereditary optic neuropathy (LHON) and Leigh syndrome challenged the longstanding assumption for LHON to be exclusively maternally inherited and broadened the genetic spectrum of Leigh syndrome, the most frequent paediatric mitochondrial disease. Herein, we characterize 28 so far unreported individuals from 26 families carrying a homozygous DNAJC30 p.Tyr51Cys founder variant, 24 manifesting with LHON, two manifesting with Leigh syndrome, and two remaining asymptomatic. This collection of unreported variant carriers confirms sex-dependent incomplete penetrance of the homozygous variant given a significant male predominance of disease and the report of asymptomatic homozygous variant carriers. The autosomal recessive LHON patients demonstrate an earlier age of disease onset and a higher rate of idebenone-treated and spontaneous recovery of vision in comparison to reported figures for maternally inherited disease. Moreover, the report of two additional patients with childhood- or adult-onset Leigh syndrome further evidences the association of DNAJC30 with Leigh syndrome, previously only reported in a single childhood-onset case. [ABSTRACT FROM AUTHOR]

Clinically approved photodynamic therapy (PDT) is a minimally invasive treatment procedure that uses three key components: photosensitization, a light source, and tissue oxygen. However, the photodynamic effect is limited by both the photophysical properties of photosensitizers as well as their low selectivity, leading to damage to adjacent normal tissue and/or inadequate biodistribution. Nanoparticles (NPs) represent a new option for PDT that can overcome most of the limitations of conventional photosensitizers and can also promote photosensitizer accumulation in target cells through enhanced permeation and retention effects. In this in vitro study, the photodynamic effect of TPP photosensitizers embedded in polystyrene nanoparticles was observed on the non-tumor NIH3T3 cell line and HeLa and G361 tumor cell lines. The efficacy was evaluated by viability assay, while reactive oxygen species production, changes in membrane mitochondrial potential, and morphological changes before and after treatment were imaged by atomic force microscopy. The tested nanoparticles with embedded TPP were found to become cytotoxic only after activation by blue light (414 nm) due to the production of reactive oxygen species. The photodynamic effect observed in this evaluation was significantly higher in both tumor lines than the effect observed in the non-tumor line, and the resulting phototoxicity depended on the concentration of photosensitizer and irradiation time. [ABSTRACT FROM AUTHOR]

Leber hereditary optic neuropathy and Dominant optic atrophy are associated with a selective loss of retinal ganglion cells (RGC). A subtype of RGC is responsible for light‐dependent physiological processes. The aim of our study was to evaluate both subjective and objective sleep parameters in 36 (18 males; mean age 33.8 ± 16.7) symptomatic/asymptomatic subjects with Leber hereditary optic neuropathy and dominant optic atrophy. The Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS) and nocturnal polysomnography were used to assess sleep disturbances and sleep quality. The questionnaires indicated significantly worse sleep quality (PSQI > 5; average 7.7 ± 3.8) in 21 (70%) and excessive daytime sleepiness (ESS > 10; average 6.3 ± 5.8) in six (20%) individuals. Nocturnal polysomnography has not revealed any significant changes of sleep structure. Rapid eye movement (REM) sleep without atonia was observed in two patients with Leber hereditary optic neuropathy. Obstructive sleep apnea was noted in eight cases. No correlation between subjective and polysomnographic data and no differences between symptomatic and asymptomatic groups were observed. None of the subjects fulfilled criteria for a circadian sleep disorder. In both symptomatic and asymptomatic individuals, a subjective decrease of the quality of sleep and wakefulness was noted without any correlation on polysomnography. [ABSTRACT FROM AUTHOR]

Photodynamic inactivation (PDI) is a promising approach for the efficient killing of pathogenic microbes. In this study, the photodynamic effect of sulfonated polystyrene nanoparticles with encapsulated hydrophobic 5,10,15,20-tetraphenylporphyrin (TPP-NP) photosensitizers on Gram-positive (including multi-resistant) and Gram-negative bacterial strains was investigated. The cell viability was determined by the colony forming unit method. The results showed no dark cytotoxicity but high phototoxicity within the tested conditions. Gram-positive bacteria were more sensitive to TPP-NPs than Gram-negative bacteria. Atomic force microscopy was used to detect changes in the morphological properties of bacteria before and after the PDI treatment. [ABSTRACT FROM AUTHOR]

Background: In this retrospective study, we analysed clinical, biochemical and molecular genetic data of 47 Czech patients with Single, Large-Scale Mitochondrial DNA Deletions (SLSMD). Methods: The diagnosis was based on the long-range PCR (LX-PCR) screening of mtDNA isolated from muscle biopsy in 15 patients, and from the buccal swab, urinary epithelial cells and blood in 32 patients. Results: A total of 57% patients manifested before the age of 16. We did not find any significant difference between paediatric and adult manifestation in either the proportion of patients that would develop extraocular symptoms, or the timespan of its progression. The survival rate in patients with Pearson Syndrome reached 60%. Altogether, five patients manifested with atypical phenotype not fulfilling the latest criteria for SLSMD. No correlation was found between the disease severity and all heteroplasmy levels, lengths of the deletion and respiratory chain activities in muscle. Conclusions: Paediatric manifestation of Progressive External Ophthalmoplegia (PEO) is not associated with a higher risk of multisystemic involvement. Contrary to PEO and Kearns-Sayre Syndrome Spectrum, Pearson Syndrome still contributes to a significant childhood mortality. SLSMD should be considered even in cases with atypical presentation. To successfully identify carriers of SLSMD, a repeated combined analysis of buccal swab and urinary epithelial cells is needed. [ABSTRACT FROM AUTHOR]

Aim: Natural or artificial substances have become an inseparable part of our lives. It is questionable whether adequate testing has been performed in order to ensure these substances do not pose a serious health risk. The principal aim of our research was to clarify the potential risk of adding essential oils to food, beverages and cosmetic products.Methods: The toxicity of substances frequently employed in cosmetics, aromatherapy and food industry (bergamot oil, Litsea cubeba oil, orange oil, citral) were investigated using cell line NIH3T3 (mouse fibroblasts) with/without UV irradiation. The MTT assay was used to estimate the cell viability. Reactive oxygen species (ROS) which are products of a number of natural cellular processes such as oxygen metabolism and inflammation were measured to determine the extent of cellular stress. DNA damage caused by strand breaks was examined by comet assay.Results: MTT test determined EC50 values for all tested substances, varying from 0.0023% v/v for bergamot oil to 0.018% v/v for citral. ROS production measurement showed that UV radiation induces oxidative stress to the cell resulting in higher ROS production compared to the control and non-irradiated samples. Comet assay revealed that both groups (UV, without UV) exert irreversible DNA damage resulting in a cell death.Conclusions: Our findings suggest that even low concentrations (lower than 0.0464% v/v) of orange oil can be considered as phototoxic (PIF value 8.2) and probably phototoxic for bergamot oil (PIF value 4.6). We also found significant changes in the cell viability, the ROS production and the DNA after the cells were exposed to the tested chemicals. Even though these substances are widely used as antioxidants it should be noted that they present a risk factor and their use in cosmetic and food products should be minimized. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) have been used for decades as anti-bacterial agents in various industrial fields such as cosmetics, health industry, food storage, textile coatings and environmental applications, although their toxicity is not fully recognized yet. Antimicrobial and catalytic activity of AgNPs depends on their size as well as structure, shape, size distribution, and physico-chemical environment. The unique properties of AgNPs require novel or modified toxicological methods for evaluation of their toxic potential combined with robust analytical methods for characterization of nanoparticles applied in relevant vehicles, e.g., culture medium with/without serum and phosphate buffered saline. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of N -aryl-2,6-diphenyl-2 H -pyrazolo[4,3- c ]pyridin-7-amines. • Photodynamic effect and no dark toxicity in melanoma G361 cells. • Cell death through production of ROS and DNA damage. A small series of N -aryl-2,6-diphenyl-2 H -pyrazolo[4,3- c ]pyridin-7-amines was synthesized from easily accessible 1-phenyl-1 H -pyrazol-3-ol via 7-iodo-2,6-diphenyl-2 H -pyrazolo[4,3- c ]pyridine and 7-iodo-4-methyl-2,6-diphenyl-2 H -pyrazolo[4,3- c ]pyridine intermediates and their subsequent use in palladium catalyzed Buchwald-Hartwig cross-coupling reaction with various anilines. Majority of the compounds were not significantly cytotoxic to melanoma G361 cells in the dark up to 10 µM concentration, but their activity could be increased by irradiation with visible blue light (414 nm). The most active compound 10 possessed EC 50 values of 3.5, 1.6 and 0.9 µM in cells irradiated with 1, 5 and 10 J/cm2, respectively. The treatment caused generation of reactive oxygen species in cells and extensive DNA damage, documented by the comet assay and by detection of phosphorylated histone H2A.X, followed by apoptotic cell death. Our results suggest that N -aryl-2,6-diphenyl-2 H -pyrazolo[4,3- c ]pyridin-7-amines could serve as a potential source of photosensitizing compounds with anticancer activities. [ABSTRACT FROM AUTHOR]

Great attention is traditionally given to the investigation of breast cancer characteristics. In the past, axillary lymph node status was the most important factor for the decision on adjuvant therapy. At present, higher accent is being laid on the characteristics of the primary tumor. Basic treatment strategy is being set just at the time of setting the diagnosis of malignant disease. For this reason it is very important to know the validity, reliability and pitfalls of the examinations of breast cancer prognostic and predictive markers. This study deals with the comparison of breast cancer characteristics set at the time of diagnosis with those verified histologically after surgery. This retrospective trial analyses data from medical records of 411 patients with early primary breast cancer treated with primary surgical procedure. Statistical analysis proved good or very good agreement between preoperative and postoperative results in following cancer characteristics: invasivity, histological type, grading, proliferative activity and percentage of steroid hormone receptors and HER-2/neu receptors. On the contrary, measurements of tumor size and settings of the numbers of tumor foci exhibited poor correlation. Biggest disagreements were described in women with preoperative histological diagnosis "carcinoma in situ": the differences were proven both for the tumor size and the number of tumor foci, and also for setting of invasiveness itself. Preoperative investigation of the axillary lymph node status has to be considered very unreliable -- the false negative rates of this investigation exceeded 92 percent. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study, linked-up with a previous study on bergamot oils, was the evaluation of phototoxic potential of essential oils (orange, lemon and Litsea cubeba), used as cosmetic ingredients. The applied tiered testing strategy included chemical analysis of the substances (by means of capillary gas chromatography/mass spectrometry), in vitro 3T3 NRU phototoxicity test and EpiDerm™ skin phototoxicity test. In order to clarify the situation in man, the highest non-phototoxic/non-cytotoxic concentrations and concentrations 10× lower (safety factor 10) were tested in vivo by means of human skin photopatch test in a limited group of human volunteers. The study revealed, that phototoxicity of the essential oils was dependent on the content of photoactive components and the solvent used. The highest non-phototoxic concentrations obtained by the skin model assay proved to be a useful starting point for subsequent confirmatory human photopatch test aimed to identify safe concentration for human use. However, the highest non-phototoxic concentration obtained in the skin model assay cannot be applied directly for human practice (3 of 8 tested oils evoked a phototoxic reaction). A safety factor of 10 should be applied for extrapolation of experimental data from the skin model assay to man. [ABSTRACT FROM AUTHOR]

The article presents a study that analyses the presence of Human alveolar echinococcosis (AE), zoonotic parasitic disease caused by larvae of Echinococcus multilocularis tapeworms, in Czech Republic from 2007-14. Topics include diagnosis of AE based on ultrasonography, confirmation of AE through histopathologic findings, and use of Mann-Whitney nonparametric test.

Dentin of human teeth is a vital hydrated tissue. It is strongly sensitive to dehydration and drying that are commonly used in preparation of samples for scanning electron microscopy. Experience in examination of dentine surfaces of extracted human third molars using contact mode atomic force microscopy under moist conditions is described. The examined dentine surfaces are modified by laser radiation produced by a pulsed Nd:YAG laser that leads to sealing of open dentinal tubules under suitable conditions that are reached after covering dentine surfaces with dye agents. Out of four investigated dye agents erythrosin solution in water has been found the most suitable and the lower and upper limits of pulse energies for sealing of dentinal tubules have been set. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Three conjugated pyrazole-indole hybrids, 5 , 7 and 10 , were synthesized from easily accessible 3-(hexyloxy)-1-phenyl-1 H -pyrazole-4-carbaldehyde 1 and 5-iodo-3,3-dimethyl-2-phenyl-3 H -indole 4 employing olefination reactions (Wittig, Ramirez), Vilsmeier-Haack formylation and palladium-catalysed cross coupling reactions (ligand-free Heck, Sonogashira). The compounds displayed no cytotoxicity in the melanoma cell line G361 unless irradiated with visible blue light (414 nm), and the potency of the compounds increased with light intensity. Lead compound 7 displayed EC50 values of 3.08, 0.26 and 0.05 μM in cells irradiated with 1, 10 and 50 J/cm2, respectively. The following experiments revealed increased levels of reactive oxygen species in treated cells and a decrease in JC-1 polymer aggregation within the mitochondria, suggesting mitochondrial membrane depolarization. In addition, extensive DNA fragmentation was detected using the comet assay and by detection of phosphorylated histone H2A.X, the level of which increased with both increased compound concentration and irradiation energy. In control experiments, cells kept either in the dark or without compound 7 did not show any DNA damage. Overall, the results demonstrated that fluorescent pyrazole-indole hybrids may serve as an interesting source of photosensitizing compounds with anticancer activity. Image 1 • Efficient synthesis of three pyrazole-indole hybrids. • Strong photodynamic effect in the human melanoma G361 cells. • Low dark toxicity. • Cell death through a production of ROS and extensive DNA damage. [ABSTRACT FROM AUTHOR]

The aim of the study was toxicological testing of an innovative and efficient antimicrobial agent based on photoactive phthalocyanine (Pc) derivative. A promising Aluminium phthalocyanine (AlPc) with efficient and stable antimicrobial effects was subjected to a battery of toxicological tests to avoid local and systemic toxicity hazard. In compliance with the current European legislation restricting the use of experimental animals, the methods comprised exclusively in vitro procedures based on cellular and tissue models of human origin or mimicking human tissues. The battery of toxicological tests to identify local toxicity included skin corrosion/irritation, eye irritation, and phototoxicity. The basic systemic toxicity tests included acute toxicity, skin sensitization, genotoxicity, and endocrine disruption. The results showed that AlPc induced skin and eye irritation, exhibited borderline sensitization potential and mutagenic potential in one test strain of the Ames test, which was not confirmed in the chromosome aberration test. The AlPc was found to be phototoxic. The results from the cytotoxicity test designed for acute oral toxicity estimation were not conclusive, the acute toxicity potential has to be determined by conventional tests in vivo. Regarding endocrine disruption, no agonistic activity of the AlPc on human estrogen receptor α, nor human androgen receptor was observed. The skin penetration/absorption test revealed that the AlPc has not penetrated into the dermis and receptor fluid, confirming no risk of systemic exposure via the bloodstream. • A novel antimicrobial phthalocyanine AlPc was tested by methods in vitro. • AlPc is a skin and eye irritant, borderline sensitizer, mutagenic in Ames test. • AlPc is phototoxic, acute toxicity was not possible to estimate in vitro. • AlPc does not penetrate through skin into the bloodstream posing no systemic risk. [ABSTRACT FROM AUTHOR]