Iron-based nanomaterials have high technological impacts on various pro-environmental applications, including wastewater treatment using the co-precipitation method. The purpose of this research was to identify the changes of iron nanomaterial's structure caused by the presence of selenium, a typical water contaminant, which might affect the removal when the iron co-precipitation method is used. Therefore, we have investigated the maturation of co-precipitated nanosized ferric oxyhydroxides under alkaline conditions and their thermal transformation into hematite in the presence of selenite and selenate with high concentrations. Since the association of selenium with precipitates surfaces has been proven to be weak, the mineralogy of the system was affected insignificantly, and the goethite was identified as an only ferric phase in all treatments. However, the morphology and the crystallinity of ferric oxyhydroxides was slightly altered. Selenium affected the structural order of precipitates, especially at the initial phase of co-precipitation. Still, the crystal integrity and homogeneity increased with time almost constantly, regardless of the treatment. The thermal transformation into well crystalized hematite was more pronounced in the presence of selenite, while selenate-treated and selenium-free samples indicated the presence of highly disordered fraction. This highlights that the aftermath of selenium release does not result in destabilization of ferric phases; however, since weak interactions of selenium are dominant at alkaline conditions with goethite's surfaces, it still poses a high risk for the environment. The findings of this study should be applicable in waters affected by mining and metallurgical operations.

• Klíčová slova
• Mössbauer spectroscopy, ferric oxyhydroxides, selenium, sorption,
• MeSH
• alkálie chemie   MeSH
• chemická precipitace MeSH
• krystalizace MeSH
• kyselina seleničitá chemie   MeSH
• kyselina selenová chemie   MeSH
• minerály chemie   MeSH
• sloučeniny železa chemie   MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• spektroskopie Mossbauerova MeSH
• teplota MeSH
• železité sloučeniny chemie   MeSH
• železo chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• alkálie MeSH
• ferric oxyhydroxide MeSH Prohlížeč
• goethite MeSH Prohlížeč
• kyselina seleničitá MeSH
• kyselina selenová MeSH
• minerály MeSH
• sloučeniny železa MeSH
• železité sloučeniny MeSH
• železo MeSH

PURPOSE: The effect of SAM vaginal gel, a medical device containing adsorptive silicon dioxide and antioxidative sodium selenite and citric acid, on histologically-proven cervical intraepithelial neoplasia type 2 (CIN2) as well as p16 positive CIN1, and on the presence of the onco-marker p16 was investigated. METHODS: 216 women aged 25-60 years were randomized to either receive an intravaginal daily dose of SAM gel for three 28-day periods, or be followed-up without intervention. The primary endpoint was efficacy, defined as a combined histological and cytological regression. At baseline and after 3 months participants had: a guided biopsy including p16 immunohistochemical (IHC) staining, only if a lesion was visible at colposcopy; a cervical smear for cytology, high-risk human papillomavirus (hr-HPV) and a p16/Ki-67 test. At 6 months a further cytology and p16/Ki-67 test was performed. RESULTS: Regression of CIN lesions was observed in 78 out of 108 patients (72.2%) in the SAM gel arm and in 27 out of 108 patients (25.0%) in the control arm. Similarly, the change in the p16/Ki-67 cytological test status was significantly in favor of the treatment arm. The prevalence of hr-HPV decreased significantly (p < 0.001) in the treatment arm, from 87.0% to 39.8%, while it slightly increased in the control arm, from 78.7% to 83.3%. At 6 months the cytological regression in the treatment group and the highly significant effect on p16/Ki-67 was still present. CONCLUSION: SAM vaginal gel enhances the regression of cervical lesions and clears hr-HPV and p16/Ki-67 in smears significantly, thus offering an active non-destructive management to prevent cervical cancer. TRIAL REGISTRATION NUMBER: ISRCTN11009040, date of registration: 10/12/2019; https://doi.org/10.1186/ISRCTN11009040 ; retrospectively registered.

• Klíčová slova
• Cervical intraepithelial neoplasia, HPV, Non-surgical treatment, Silicon dioxide, Sodium selenite, p16/Ki-67 dual staining,
• MeSH
• antigen Ki-67 účinky léků   MeSH
• antioxidancia aplikace a dávkování   MeSH
• aplikace intravaginální MeSH
• cytodiagnostika MeSH
• dospělí MeSH
• dysplazie děložního hrdla patologie   terapie   MeSH
• geny p16 MeSH
• infekce papilomavirem terapie   virologie   MeSH
• inhibitor p16 cyklin-dependentní kinasy účinky léků   MeSH
• kolposkopie MeSH
• kyselina citronová aplikace a dávkování   MeSH
• lidé středního věku MeSH
• lidé MeSH
• nádorové biomarkery analýza   MeSH
• nádory děložního čípku prevence a kontrola   MeSH
• oxid křemičitý aplikace a dávkování   MeSH
• seleničitan sodný aplikace a dávkování   MeSH
• těhotenství MeSH
• vaginální krémy, pěny a želé * MeSH
• vaginální stěr MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH
• Názvy látek
• antigen Ki-67 MeSH
• antioxidancia MeSH
• inhibitor p16 cyklin-dependentní kinasy MeSH
• kyselina citronová MeSH
• nádorové biomarkery MeSH
• oxid křemičitý MeSH
• seleničitan sodný MeSH
• vaginální krémy, pěny a želé * MeSH

The specific effects of sodium selenite (selenite) on a chemoresistant human bladder cancer cell line RT-112/D21 were investigated during 72 h. Selenite at low concentration of 2.5 μmol (otherwise tolerated in normal urothelial cells UROtsa) suppressed growth and proliferation of the tested cancer cells via induced oxidative stress. Selenite further altered mitochondrial functions (i.e. decreased mitochondrial membrane potential, increased production of superoxide and reduced ATP synthesis), disrupted lysosomal membranes and activated autophagy. These changes in selenite-exposed cells ultimately resulted in their demise via necrosis and other cell death modality displaying heterotypic apoptotic and autophagic features.

• Klíčová slova
• Autophagic cell death, Bladder cancer, Lysosomes, Mitochondria, Necrosis, Selenite,
• MeSH
• apoptóza účinky léků   MeSH
• autofagie účinky léků   MeSH
• buněčná smrt účinky léků   MeSH
• chemorezistence účinky léků   MeSH
• lidé MeSH
• lyzozomy účinky léků   metabolismus   MeSH
• membránový potenciál mitochondrií účinky léků   MeSH
• mitochondrie účinky léků   metabolismus   MeSH
• nádorové buněčné linie MeSH
• nádory močového měchýře farmakoterapie   metabolismus   patologie   MeSH
• proliferace buněk účinky léků   MeSH
• seleničitan sodný farmakologie   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• seleničitan sodný MeSH

We have investigated the cytotoxicity and specific effects of selenite in human bladder cancer cell line RT-112 and its clonogenic variant RT-112 HB. Selenite inhibited cell growth and proliferation in both cell lines. Treated cells developed extensive vacuolization which was dose independent but occurring in differing time frames. Ultrastructure analysis revealed that the observed vacuoles are damaged mitochondria and potentially other subcellular compartments. Selenite-specific effects on mitochondria were further confirmed by mitochondrial membrane potential analysis, changes in ATP production and generation of superoxide. Simultaneously, selenite induced DNA damage in treated cells with activation of p53, PARP-1 and JNK and suppressed autophagy. Cells ultimately died via a combination of apoptosis, necrosis and a distinct type of cell death featuring "vacuolar shrinkage", loss of adherence and absence of secondary necrosis as well as other classical markers of either apoptosis or autophagy. The significant presence of so called necroptosis was also not confirmed as the specific inhibitor necrostatin-1 could not prevent cell death. These results thus confirm the toxicity of selenite in bladder cancer cells while pointing at potentially new mechanism of action of this compound in this model.

• Klíčová slova
• Bladder cancer, DNA damage, Mitochondria, Necroptosis, Necrosis, Selenite,
• MeSH
• apoptóza účinky léků   MeSH
• kyselina seleničitá toxicita   MeSH
• lidé MeSH
• membránový potenciál mitochondrií účinky léků   MeSH
• mitochondrie účinky léků   fyziologie   MeSH
• nádorové buněčné linie MeSH
• nádorový supresorový protein p53 metabolismus   MeSH
• nádory močového měchýře metabolismus   patologie   MeSH
• nekróza chemicky indukované   MeSH
• poškození DNA * MeSH
• superoxidy metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kyselina seleničitá MeSH
• nádorový supresorový protein p53 MeSH
• superoxidy MeSH

AIMS: To identify bacteria with high selenium tolerance and reduction capacity for bioremediation of wastewater and nanoselenium particle production. METHODS AND RESULTS: A bacterial endophyte was isolated from the selenium hyperaccumulator Stanleya pinnata (Brassicaceae) growing on seleniferous soils in Colorado, USA. Based on fatty acid methyl ester analysis and multi-locus sequence analysis (MLSA) using 16S rRNA, gyrB, rpoB and rpoD genes, the isolate was identified as a subspecies of Pseudomonas moraviensis (97.3% nucleotide identity) and named P. moraviensis stanleyae. The isolate exhibited extreme tolerance to SeO3(2-) (up to 120 mmol l(-1)) and SeO4(2-) (>150 mmol l(-1)). Selenium oxyanion removal from growth medium was measured by microchip capillary electrophoresis (detection limit 95 nmol l(-1) for SeO3(2-) and 13 nmol l(-1) for SeO4(2-)). Within 48 h, P. moraviensis stanleyae aerobically reduced SeO3(2-) to red Se(0) from 10 mmol l(-1) to below the detection limit (removal rate 0.27 mmol h(-1) at 30 °C); anaerobic SeO3(2-) removal was slower. No SeO4(2-) removal was observed. Pseudomonas moraviensis stanleyae stimulated the growth of crop species Brassica juncea by 70% with no significant effect on Se accumulation. CONCLUSIONS: Pseudomonas moraviensis stanleyae can tolerate extreme levels of selenate and selenite and can deplete high levels of selenite under aerobic and anaerobic conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: Pseudomonas moraviensis subsp. stanleyae may be useful for stimulating plant growth and for the treatment of Se-laden wastewater.

• Klíčová slova
• Pseudomonas moraviensis, Stanleya pinnata, aerobic selenite reduction, elemental selenium nanoparticles, microchip capillary electrophoresis, multi-locus sequence analysis,
• MeSH
• aerobióza MeSH
• biodegradace MeSH
• Brassicaceae metabolismus   mikrobiologie   MeSH
• endofyty klasifikace   genetika   izolace a purifikace   metabolismus   MeSH
• kyselina seleničitá metabolismus   MeSH
• Pseudomonas klasifikace   genetika   izolace a purifikace   metabolismus   MeSH
• selen metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kyselina seleničitá MeSH
• selen MeSH

Effects of chronic exposure to supranutritional sodium selenite (Se) were investigated in colonic fibroblasts. Initially, Se did not produce any gross changes in exposed cells; however, basal levels of autophagy were transiently increased and p38 activity was stimulated. From the 3rd week onwards, Se decreased cell proliferation, with corrensponding changes in cell cycle distribution. Also, in exposed cells oxidative stress and DNA damage slowly but gradually increased along with decreasing mitochondrial function and upon continued elevated activity of p38 kinase. Towards the end of the experiment, premature senescence features became more prominent in treated cells. Pharmacological inhibition as well as gene knockdown of these processes confirmed the involvement of p38 in balancing autophagy and premature senescence in cells exposed to Se and suggests that this element may in a given time frame compromise selected cell populations in digestive system.

• Klíčová slova
• Autophagy, Colonic fibroblasts, Mitochondria, Premature senescence, Sodium selenite, p38,
• MeSH
• aktivace enzymů MeSH
• autofagie účinky léků   MeSH
• buněčné linie MeSH
• buněčný cyklus účinky léků   MeSH
• časové faktory MeSH
• fenotyp MeSH
• fibroblasty účinky léků   enzymologie   patologie   MeSH
• kolon účinky léků   enzymologie   patologie   MeSH
• lidé MeSH
• metylace DNA účinky léků   MeSH
• mitochondrie účinky léků   enzymologie   patologie   MeSH
• mitogenem aktivované proteinkinasy p38 metabolismus   MeSH
• oxidační stres účinky léků   MeSH
• poškození DNA MeSH
• proliferace buněk účinky léků   MeSH
• replikace DNA účinky léků   MeSH
• seleničitan sodný toxicita   MeSH
• signální transdukce účinky léků   MeSH
• stárnutí buněk účinky léků   MeSH
• transfekce MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• mitogenem aktivované proteinkinasy p38 MeSH
• seleničitan sodný MeSH

Yearling common barbel (Barbus barbus L.) were fed four purified casein-based diets for 6 weeks in outdoor cages. Besides control diet, these were supplemented with 0.3 mg kg(-1) dw selenium (Se) from sodium selenite, or 0.3 and 1.0 mg kg(-1) from Se-enriched microalgae biomass (Chlorella), a previously untested Se source for fish. Fish mortality, growth, Se accumulation in muscle and liver, and activity of selected enzymes in blood plasma, muscle, liver, and intestine were evaluated. There was no mortality, and no differences in fish growth, among groups. Se concentrations in muscle and liver, activity of alanine aminotransferase and creatine kinase in blood plasma, glutathione reductase (GR) in muscle, and GR and catalase in muscle and liver suggested that selenium from Se-enriched Chlorella is more readily accumulated and biologically active while being less toxic than sodium selenite.

• MeSH
• antioxidancia metabolismus   MeSH
• biomasa MeSH
• Cyprinidae růst a vývoj   metabolismus   MeSH
• glutathionperoxidasa krev   MeSH
• játra enzymologie   metabolismus   MeSH
• krmivo pro zvířata MeSH
• mikrořasy chemie   MeSH
• potravní doplňky MeSH
• selen aplikace a dávkování   MeSH
• seleničitan sodný aplikace a dávkování   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antioxidancia MeSH
• glutathionperoxidasa MeSH
• selen MeSH
• seleničitan sodný MeSH

Sodium selenite (Se) is known to induce diverse stress responses in malignant cells which may lead to various types of cell death including apoptosis and/or autophagy. In colon cancer cells, Se activates several signaling pathways whose interactions and ultimate endpoints may vary in individual study models. In our previous work we showed differences in Se-dependent growth inhibition, cell cycle alterations and apoptosis in colon cancer cells with functional (HCT-116) and deleted (HCT-116-p53KO) p53. Moreover, detailed morphological and biochemical analyses revealed the presence of autophagy in Se-treated cells. Thus the aim of this study was to investigate in detail mechanisms, relationship and crosstalk between apoptosis and autophagy in Se-treated HCT-116 cancer cells differing in p53 status since p53 has been shown to play a well-known role in apoptosis but dichotomous role in autophagy. We report that the absence of p53 in malignant colonocytes changes patterns of response to Se-induced stress which include differential activation of MAP kinases (p38 - HCT-116 and JNK - HCT-116 p53KO) including their respective roles in the process of apoptosis and autophagy as well as the involvement of mTOR or PI3K signaling. Our results seem to suggest that deletion of p53 inevitably leads to a higher level of instability and delays in an individual cell decision in the face of stress whether to activate apoptosis or autophagy which may consequently occur simultaneously with mutual dichotomous relationship.

• MeSH
• antikarcinogenní látky farmakologie   MeSH
• apoptóza účinky léků   MeSH
• autofagie účinky léků   MeSH
• genový knockdown MeSH
• HCT116 buňky MeSH
• lidé MeSH
• mitogenem aktivované proteinkinasy metabolismus   MeSH
• nádorový supresorový protein p53 nedostatek   genetika   MeSH
• nádory tračníku metabolismus   patologie   MeSH
• poškození DNA MeSH
• protein bcl-X metabolismus   MeSH
• protein X asociovaný s bcl-2 metabolismus   MeSH
• protoonkogenní proteiny c-bcl-2 metabolismus   MeSH
• seleničitan sodný farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antikarcinogenní látky MeSH
• BCL2L1 protein, human MeSH Prohlížeč
• mitogenem aktivované proteinkinasy MeSH
• nádorový supresorový protein p53 MeSH
• protein bcl-X MeSH
• protein X asociovaný s bcl-2 MeSH
• protoonkogenní proteiny c-bcl-2 MeSH
• seleničitan sodný MeSH

The function of selenium in an organism is mediated mostly by selenoproteins including glutathione peroxidase. Glutathione peroxidase is a potent anti-oxidative enzyme, scavenging a variety of peroxides. The green alga Scenedesmus quadricauda was used to investigate the relationship between the toxicity of selenium and the glutathione peroxidase activity. Selenium resistant strains SeIV and SeVI were synchronized and grown in high concentrations of Se (selenite or selenate). As a measure of selenium toxicity the EC(50) values were determined. During growth of the untreated wild type, glutathione peroxidase activity increased slightly and then declined gradually until the end of the cell cycle. A similar pattern was observed in untreated resistant strains and when resistant strains were grown in the presence of selenium in the oxidation state to which they were resistant. In the wild type cultivated with 50 mg Se L(-1) (selenite or selenate), activity increased to a high level and slowly declined until the end of the cell cycle. Similarly, activity increased in strains SeIV and SeVI when grown in the presence of selenium in the oxidation state to which they were not resistant. We followed the effect of selenium on the ultrastructure of S. quadricauda. After exposure to selenite, the chloroplast membranes of wild type were reorganized into thick bundles of thylakoids and the stroma became granulose. When selenate was added, the chloroplast of wild type had a fingerprint-like appearance, the stroma became less dense and starch production increased. In selenium resistant strains, when treated with the selenium form to which they were resistant, the chloroplast was affected, but not to such an extent as in the wild type. The activity of glutathione peroxidase in Scenedesmus was affected by selenium in an oxidation state-dependent manner. The most apparent effects of selenium on the ultrastructure involved impairment of the chloroplast and the overproduction of starch.

• MeSH
• buněčný cyklus účinky léků   fyziologie   MeSH
• chloroplasty účinky léků   metabolismus   ultrastruktura   MeSH
• fyziologický stres MeSH
• geneticky modifikované rostliny MeSH
• glutathionperoxidasa metabolismus   MeSH
• kultivační techniky MeSH
• kyselina selenová MeSH
• Scenedesmus cytologie   účinky léků   enzymologie   fyziologie   MeSH
• selen aplikace a dávkování   analýza   toxicita   MeSH
• seleničitan sodný aplikace a dávkování   toxicita   MeSH
• sloučeniny selenu aplikace a dávkování   toxicita   MeSH
• testy toxicity MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• glutathionperoxidasa MeSH
• kyselina selenová MeSH
• selen MeSH
• seleničitan sodný MeSH
• sloučeniny selenu MeSH

The aim of this study was to investigate the effects of selenium (Se) on the growth, accumulation and possible mechanisms of Se transport in certain parts (roots, leaves, stamp and apex) of nettle (Urtica dioica L.) plants. Se was supplemented by one-shot and two repeated doses to the soil (2.0 and 4.0 mg Se per kg of substrate). Selenium content in roots increased linearly with dose and was significantly higher compared to other plant parts of interest. However, growth of the above-ground parts of plant as well as roots was slightly inhibited with increasing selenium concentration in comparison to the untreated plants. The content of phytochelatin2, a low molecular mass peptide containing a sulfhydryl group, correlated well with the Se content. This suggests a possible stimulation of synthesis of this plant peptide by Se.

• Klíčová slova
• graphite furnace atomic absorption spectrometry, heavy metal, high performance liquid chromatography with electrochemical detection, nettle, plant, plant tissues, selenium,
• MeSH
• seleničitan sodný farmakologie   MeSH
• spektrofotometrie atomová MeSH
• Urtica dioica účinky léků   MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• seleničitan sodný MeSH