• MeSH
• dieta MeSH
• injekce subkutánní MeSH
• izotopy rtuti MeSH
• izotopy zinku MeSH
• kadmium krev   metabolismus   MeSH
• krysa rodu Rattus MeSH
• radionuklidy MeSH
• rtuť krev   metabolismus   MeSH
• selen farmakologie   MeSH
• zinek krev   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• izotopy rtuti MeSH
• izotopy zinku MeSH
• kadmium MeSH
• radionuklidy MeSH
• rtuť MeSH
• selen MeSH
• zinek MeSH

The use of quantum dots (QD) in various medical and industrial applications may cause these nanoparticles to leak into waterways and subsequently enter the food chain. Therefore, if we intend to use QD, we must first know their potential environmental implications. In this work, cadmium selenide/zinc sulfide core/shell QD were synthesized, and then, biocompatible, water-dispersed QD were coated with silica (Si-QD). The QD were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) combined with energy-dispersive X-ray spectroscopy (EDX), and UV-Vis absorption analysis, which revealed that these surface-engineered QD have a highly crystalline, homogeneous spherical shape measuring approximately 25 nm. The cytotoxicity of the nanoparticles in the green algae Chlamydomonas reinhardtii was studied by incubating the algae cells with Si-QD and determining the optical density of algal cell culture, cell counts, and cells sizes by microflow cytometry. These measurements indicated that Si-QD are biocompatible up to a concentration of 25 ng/ml. Finally, the cellular uptake of Si-QD into C. reinhardtii was monitored by confocal laser scanning microscopy (CLSM). In conclusion, our results reveal that surface-engineered Cd-QD can penetrate the cells of aquatic organisms, which ensures a serious impact on the food chain and consequently the environment. On the other hand, the results also highlight a new potential method for bioremediation of Cd-QD by green algae, especially C. reinhardtii.

• Klíčová slova
• Bioremediation, Confocal microscopy, Ecotoxicity, Internalization of nanomaterials, Nanocrystals, Photosynthetic organisms,
• MeSH
• Chlamydomonas reinhardtii účinky léků   MeSH
• kovové nanočástice chemie   toxicita   MeSH
• kvantové tečky chemie   toxicita   MeSH
• sloučeniny kadmia toxicita   MeSH
• sloučeniny selenu toxicita   MeSH
• sloučeniny zinku toxicita   MeSH
• sulfidy toxicita   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cadmium selenide MeSH Prohlížeč
• sloučeniny kadmia MeSH
• sloučeniny selenu MeSH
• sloučeniny zinku MeSH
• sulfidy MeSH
• zinc sulfide MeSH Prohlížeč

The objective of the study was to test the effectiveness of Zn, Se and Cu supplementation through reticulum-rumen pellets and its effects on the rate of cellular and humoral reactions in sheep. An experiment included 12 lambing ewes of the Merino breed at the age of two years. Zn-containing pellets were applied via rumen to three lambing ewes at the end of November, Se pellets were applied to other three lambing ewes Cu pellets to other three ewes. Three lambing ewes were control. Blood samples were taken from the v. jugularis from all the investigated ewes before bolus administration, in month 1, 2, 3, 4, 6 and 7 after application. Zn, Se and Cu concentrations in the blood serum were determined by atomic absorption spectrophotometry. Immune reactions were evaluated from the concentrations of serum immunoglobulins (IgC), albumin (ALB), total proteins (TP), from phagocytic activity (PA), phagocytic index (PI), migration-inhibitory test (MIT) and determination of tetrazolium-reductase activity of phagocytes (INT-test). In comparison with the starting values, the highest increase in zincemia (80%) was recorded in the lambing ewes administered zinc boluses as soon as in the 1st month after administration. A significant difference in Zn concentrations between the zinc-pellet group and the control animals was observed in the 1st month after administration (P < 0.01). An increase in Se concentrations in the blood serum was observed in the lambing ewes administered selenium boluses in the 1st month after administration. Se content in the blood serum of the given group of ewes was highest at the end of observation (2.72 +/- 0.29 mumol/l). A statistically significant difference in Se content between the group of selenium-bolus ewes and the control ewes was confirmed at a significance level P < 0.05 in the 1st and 2nd month of the experiment. Cu concentrations in the blood serum in the Cu-bolus ewes increased in the 1st month if compared with the starting values. The highest Cu concentration in the blood serum was recorded in the given group within month 4 to 7 of the experiment (16.53 +/- 2.72, or 21.23 +/- 4.40 mumol/l). There were significant differences in cupremia between the Cu-pellet group of ewes and the control animals (P < 0.05). In comparison with the starting values, the highest increase in TP concentrations were determined in the Cu-pellet ewes in the 4th, 6th, and 7th months. Albuminemia dynamics in the experimental animals and in the control group did not vary significantly.(ABSTRACT TRUNCATED AT 250 WORDS)

• MeSH
• bachor MeSH
• imunita účinky léků   MeSH
• krmivo pro zvířata * MeSH
• měď aplikace a dávkování   MeSH
• ovce imunologie   MeSH
• selen aplikace a dávkování   MeSH
• zinek aplikace a dávkování   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• měď MeSH
• selen MeSH
• zinek MeSH

The objective of this study was to evaluate the presence of heavy metals in the hepatocytes of the animals fed a cadmium-supplemented diet and also receiving zinc and/or selenium in the injection form. The experiment involved four groups of calves (6-8, both sexes) receiving the heavy metals in various combinations for 95 days. Electron micrographs of liver cells were prepared and statistically evaluated using Student's t-test. A modified morphometric apparatus was used for morphometric examination. Exogenous cadmium showed marked accumulation in the hepatocytes. If, however, the cadmium diet was combined with zinc or selenium administration the amount of the reduction product was much lower.

• MeSH
• elektronová mikroskopie MeSH
• hepatocyty metabolismus   ultrastruktura   MeSH
• kadmium aplikace a dávkování   metabolismus   MeSH
• krmivo pro zvířata MeSH
• selen aplikace a dávkování   metabolismus   MeSH
• skot metabolismus   MeSH
• těžké kovy aplikace a dávkování   metabolismus   MeSH
• zinek aplikace a dávkování   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• skot metabolismus   MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kadmium MeSH
• selen MeSH
• těžké kovy MeSH
• zinek MeSH

The formation of self-assemblies between CdSe quantum dots (QDs) and Zn phthalocyanines (Pc) and azaphthalocyanines (AzaPc) bearing alkylsulfanyl substituents and the photophysical properties of these assemblies were studied using both steady-state and time-resolved luminescence/absorption spectroscopy. The formation of the self-assemblies was accompanied by a blue shift of the Q band of the dyes and by a quenching of the CdSe QDs luminescence. The largest spectral shift of the Q-band was approximately 7 nm and was observed for pentan-3-ylsulfanyl-functionalised phthalocyanine (). Assuming a 1 : 1 stoichiometry, the calculated binding constant was 4 × 10(4) M(-1). Pc substituted with the bulky tert-butylsulfanyl groups (1) exhibited a smaller shift of the Q band. The quenching of the CdSe QDs luminescence by 1 was more effective than that observed for 3. The results indicated that the luminescence quenching may be due to a photoinduced charge transfer between 1 or 3 and the CdSe QDs. In contrast, the AzaPc (2) with the same substituents as 1 had little effect on the QDs luminescence. For all cases, we found an inefficient resonance energy transfer between the attached dyes and the CdSe QD. The formation of the self-assemblies had negligible effects on the photogeneration of the singlet oxygen, O2((1)Δg), that was fully controlled only by the absorption of the light by the macrocycles.

• MeSH
• fluorescenční spektrometrie MeSH
• indoly chemie   MeSH
• isoindoly MeSH
• kvantová teorie MeSH
• kvantové tečky * MeSH
• organokovové sloučeniny chemie   MeSH
• rozpouštědla chemie   MeSH
• sloučeniny kadmia chemie   MeSH
• sloučeniny selenu chemie   MeSH
• sloučeniny zinku MeSH
• velikost částic MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• cadmium selenide MeSH Prohlížeč
• indoly MeSH
• isoindoly MeSH
• organokovové sloučeniny MeSH
• phthalocyanine MeSH Prohlížeč
• rozpouštědla MeSH
• sloučeniny kadmia MeSH
• sloučeniny selenu MeSH
• sloučeniny zinku MeSH
• Zn(II)-phthalocyanine MeSH Prohlížeč

• MeSH
• anemie krev   metabolismus   MeSH
• kobalt krev   metabolismus   MeSH
• lidé MeSH
• mozek - chemie MeSH
• mozek metabolismus   MeSH
• rubidium krev   metabolismus   MeSH
• selen krev   metabolismus   MeSH
• stopové prvky krev   metabolismus   MeSH
• železo krev   metabolismus   MeSH
• zinek krev   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• kobalt MeSH
• rubidium MeSH
• selen MeSH
• stopové prvky MeSH
• železo MeSH
• zinek MeSH

Nanotechnology, new fascinating field of science, is bringing many application's options. However, it is necessary to understand their potential environmental risk and toxicity. Zinc selenide quantum dots (ZnSe QDs) are getting valuable due to wide industrial usage, mainly as cadmium free diodes or stabilizing ligand. Thanks to unique properties, they could also open the possibilities of application in the agriculture. Their effects on living organisms, including plants, are still unknown. Therefore, the attention of this work was given to antioxidant response of Arabidopsis thaliana to 100 and 250 μM ZnSe QDs foliar feeding. ZnSe QDs treatment had no statistically significant differences in morphology but led to increased antioxidant response in the leaves at the level of gene expression and production secondary antioxidant metabolites. Concurrently, analysis of growth properties of Agrobacterium tumefaciens was done. 250 μM ZnSe solution inhibited the Agrobacterium tumefaciens viability by 60%. This is the first mention about effect ZnSe QDs on the plants. Although QDs induced oxidative stress, the apply treatment dose of ZnSe QDs did not have significant toxic effect on the plants and even no morphological changes were observed. However, the same amount of ZnSe QD induced an inhibitory effect on Agrobacterium tumefaciens.

• Klíčová slova
• A. tumefaciens, Arabidopsis thaliana, Toxicity, ZnSe QDs,
• MeSH
• Agrobacterium tumefaciens účinky léků   růst a vývoj   MeSH
• antioxidancia metabolismus   MeSH
• Arabidopsis genetika   růst a vývoj   metabolismus   MeSH
• exprese genu * MeSH
• kvantové tečky toxicita   MeSH
• metabolomika * MeSH
• sloučeniny selenu aplikace a dávkování   toxicita   MeSH
• sloučeniny zinku aplikace a dávkování   toxicita   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antioxidancia MeSH
• sloučeniny selenu MeSH
• sloučeniny zinku MeSH
• zinc selenide MeSH Prohlížeč

The authors present the result of their work where they provide evidence that in inflammatory and degenerative diseases the break-down on superoxide in inadequate. This oxygen radicals and its metabolites play a significant role in the pathogenesis of these diseases. The authors revealed a severe defect in superoxide degeneration in particular in articular exudates of patients with active synovitis. Administration of the preparation Selzink-Plus of PRO.MED.CS Co. Prague which contains selenium, zinc, beta-cyrotene, vitamin C and E along with antirheumatic treatment improves according to the authors the breakdown of superoxide and its metabolites and improves thus the patient's prognosis. Long-term administration of the preparation seems to produce even better results.

• MeSH
• artritida patofyziologie   MeSH
• fixní kombinace léků MeSH
• lidé MeSH
• selen terapeutické užití   MeSH
• superoxidy metabolismus   MeSH
• vitaminy terapeutické užití   MeSH
• volné radikály metabolismus   MeSH
• zinek terapeutické užití   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• fixní kombinace léků MeSH
• selen MeSH
• superoxidy MeSH
• vitaminy MeSH
• volné radikály MeSH
• zinek MeSH

BACKGROUND: Trace elements--zinc, copper and selenium are part of antioxidant enzymes, superoxide dismutase (SOD) and glutathione peroxidase (GHPx). In renal diseases changes in the trace element metabolism may influence the equilibrium in the antioxidant defence system and enhance the toxic effect of reactive oxygen molecules. METHODS AND RESULTS: The authors examined in 53 children with chronic neprophathies (34 with chronic glomerulonephritis, 11 with chronic renal failure and 8 children included in a chronic dialyzation programme) zinc and selenium in blood and urine and antioxidant enzymes SOD and GHPx in red blood cells. The lowest SOD activity (737 +/- 219 U/g Hb, p < 0.01) and serum zinc concentration (12.9 +/- 3.2, p < 0.05) were found in children in the terminal stage of uraemia, GHPx was as compared with the group of healthy children elevated in all groups of sick children. In dialysed children GHPx was highest (p < 0.01) and correlated with urinary selenium concentrations (r = -0.86, p < 0.05). The SOD activity depended on the serum copper concentrations (r = 0.78, p < 0.05). The highest renal zinc and selenium excretion was recorded in patients with glomerulonephritis (p < 0.05). CONCLUSIONS: The results support the hypothesis on a causal relationship between trace elements and antioxidant enzymes.

• MeSH
• antioxidancia metabolismus   MeSH
• chronická nemoc MeSH
• chronické selhání ledvin metabolismus   terapie   MeSH
• dialýza ledvin MeSH
• dítě MeSH
• glomerulonefritida metabolismus   MeSH
• glutathionperoxidasa metabolismus   MeSH
• lidé MeSH
• mladiství MeSH
• selen metabolismus   MeSH
• stopové prvky metabolismus   MeSH
• superoxiddismutasa metabolismus   MeSH
• zinek metabolismus   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mladiství MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• antioxidancia MeSH
• glutathionperoxidasa MeSH
• selen MeSH
• stopové prvky MeSH
• superoxiddismutasa MeSH
• zinek MeSH

The green alga Scenedesmus obliquus was incubated with heavy metals (Cd2+, Zn2+, Mn2+, Ni2+) with and without selenium. S. obliquus exhibited higher rates of growth and some metabolic activities in cultures containing 0.1 mmol/L Se than those only containing the heavy metals. The positive effect of Se was found with all metals but was negligible with Mn2+.

• MeSH
• chemické látky znečišťující vodu toxicita   MeSH
• chlorofyl metabolismus   MeSH
• Chlorophyta účinky léků   růst a vývoj   metabolismus   MeSH
• ekosystém MeSH
• fotosyntéza účinky léků   MeSH
• kadmium toxicita   MeSH
• lékové interakce MeSH
• mangan MeSH
• nikl toxicita   MeSH
• selen farmakologie   MeSH
• těžké kovy toxicita   MeSH
• zinek toxicita   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chemické látky znečišťující vodu MeSH
• chlorofyl MeSH
• kadmium MeSH
• mangan MeSH
• nikl MeSH
• selen MeSH
• těžké kovy MeSH
• zinek MeSH