In this study, oxidative stress-related parameters and As retention were examined in liver and kidneys of male Wistar rats exposed to arsenic trioxide, sodium arsenite (iAsIII), sodium arsenate (iAsV), and dimethylarsinic acid (DMAsV) at a single ip dose of 3.8 mgAs/kgbw, at 24h post-exposure. In liver, lipid peroxidation increased in iAsIII-exposed rats, glutathione peroxidase activity decreased in inorganic arsenic (iAs)-exposed rats, and catalase and thioredoxin reductase activities decreased significantly in all As-exposed groups. Both As(III) and As(V) exposure elevated GSH level with no effect on glutathione reductase activity. In kidneys, catalase activity decreased significantly in iAs-exposed, rats; GSH level, glutathione reductase and thioredoxin reductase activity decreased in DMAsV-treated, rats. The tissue As retention was higher in kidneys compared to liver and was also higher in As(III)-exposed compared to As(V)-exposed rats. The results demonstrate similar potency of inorganic As(III) and As(V) compounds to inhibit/induce antioxidant defense system, with liver being more vulnerable to acute As(III)- and As(V)-induced oxidative stress.

• Klíčová slova
• Arsenate, Arsenic trioxide, Arsenite, Dimethylarsinic acid, Oxidative stress, Selenoenzymes,
• MeSH
• antioxidancia metabolismus   MeSH
• arsen analýza   MeSH
• arsenikové přípravky * MeSH
• glutathion metabolismus   MeSH
• indikátory a reagencie MeSH
• játra účinky léků   metabolismus   MeSH
• krysa rodu Rattus MeSH
• ledviny účinky léků   metabolismus   MeSH
• peroxidace lipidů účinky léků   MeSH
• potkani Wistar MeSH
• selen farmakologie   MeSH
• thioredoxin-disulfidreduktasa metabolismus   MeSH
• thioredoxiny metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antioxidancia MeSH
• arsen MeSH
• arsenikové přípravky * MeSH
• glutathion MeSH
• indikátory a reagencie MeSH
• selen MeSH
• thioredoxin-disulfidreduktasa MeSH
• thioredoxiny MeSH

Sequestration of arsenic to biogenic sulfide minerals is known from As-contaminated anoxic environments. Despite numerous successful laboratory experiments, the process remains difficult to predict in moderate arsenic conditions. We performed microcosm experiments using naturally contaminated groundwater (containing ca. 6 mg/L As) and natural organic matter (NOM) particles both collected from wetland soil. Macroscopic realgar precipitates, occasionally accompanied by bonazziite, a FeS phase, elementary S, calcite, and whewellite, appeared after 4 to 18 months. Realgar only precipitated in microcosms moderately poisoned by azide or antibiotics and those in which oxidation of hydrogen sulfide to sulfur took place. The biomineralization process was not affected by the presence of additional carbon sources or the diversity, community structure, and functional composition of the microbial community. Hydrogen sulfide concentration was greater in the realgar-free microcosms, suggesting that arsenic thiolation prevented precipitation of realgar. We compared our data to available microbial community data from soils with different rates of realgar precipitation, and found that the communities from realgar-encrusted NOM particles usually showed limited sulfate reduction and the presence of fermentative metabolisms, whereas communities from realgar-free NOM particles were strongly dominated by sulfate reducers. We argue that the limited sulfate supply and intensive fermentation amplify reducing conditions, which make arsenic sulfide precipitation plausible in high-sulfate, low-arsenic groundwaters.

• Klíčová slova
• Arsenic, Arsenic thiolation, Fermentation, Microcosm, Realgar biomineralization, Sulfate reduction,
• MeSH
• arsenikové přípravky analýza   MeSH
• biomineralizace * MeSH
• chemické látky znečišťující vodu analýza   MeSH
• huminové látky analýza   MeSH
• mikrobiota * MeSH
• mokřady MeSH
• oxidace-redukce MeSH
• podzemní voda chemie   mikrobiologie   MeSH
• půda chemie   MeSH
• sírany chemie   MeSH
• sulfidy analýza   MeSH
• teoretické modely MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• arsenic disulfide MeSH Prohlížeč
• arsenikové přípravky MeSH
• chemické látky znečišťující vodu MeSH
• huminové látky MeSH
• půda MeSH
• sírany MeSH
• sulfidy MeSH

OBJECTIVES: The aim of this study was to investigate the associations between urinary arsenic, oxidative stress, assessed by thiol/disulphide homeostasis, and lung diseases in firefighters. METHODS: The study conducted among the municipality-based male firefighters (n = 100) who were admitted to occupational diseases clinic for periodic medical examination. The control group consisted of non-exposed male office workers (n = 50). Urinary arsenic levels, thiol/disulphide homeostasis parameters of participants were determined. Also, lung diseases were assessed by chest X-ray and pulmonary function tests. RESULTS: The mean age and work year did not differ in the study and control group. The median urinary arsenic concentration of firefighters was significantly higher than in the control group: 15.65 (2.5-246) μg/L and 3 (0.10-6) μg/L, respectively (p < 0.001). The parameters of pulmonary function tests (PFT) FVC (%), FEV1 (%), FEV1/FVC ratio and FEF 25-75 (%) were all significantly lower in firefighters compared to controls. A significant increase in mean serum disulphide concentration (17.10 ± 8.31 μmol/L vs. 7.48 ± 5.91) (Fig. 1) and disulphide/native thiol % ratio: 3.63 (0.53-11.43) vs. 1.51 (0.03-7.65) (p < 0.001) were found between exposed group and controls. The Spearman's correlation analysis revealed a positive correlation between urinary arsenic and disulphide (r = 0.422, p < 0.001), disulphide/native thiol % ratio (r = 0.409, p < 0.001). Nevertheless, urinary arsenic correlated negatively with all PFT parameters including FVC (%), FEV1 (%), FEV1/FVC and FEF 25-75 (%) (p < 0.001). CONCLUSION: We showed the arsenic-induced oxidative stress in firefighters with impairments of several lung functions determined by thiol/disulphide homeostasis using a novel method.

• Klíčová slova
• X-ray abnormality, arsenic, firefighters, respiratory function disorder, thiol/disulphide homeostasis,
• MeSH
• arsen moč   MeSH
• biologické markery krev   moč   MeSH
• časná diagnóza MeSH
• disulfidy krev   MeSH
• dospělí MeSH
• hasiči * MeSH
• homeostáza MeSH
• lidé MeSH
• oxidační stres MeSH
• plicní nemoci krev   diagnóza   patofyziologie   MeSH
• rentgendiagnostika hrudníku MeSH
• respirační funkční testy MeSH
• sulfhydrylové sloučeniny krev   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Turecko MeSH
• Názvy látek
• arsen MeSH
• biologické markery MeSH
• disulfidy MeSH
• sulfhydrylové sloučeniny MeSH

Raman spectral signatures have been obtained in situ for a series of minerals using portable Raman instruments. Cerussite, anglesite, wulfenite, titanite, calcite, tremolite, andradite and quartz were detected using portable Raman spectrometer First Defender XL (Ahura). Baryte, almandine and realgar Raman spectra obtained by this instrument in the field were compared to the data measured by the other mobile Raman instrument Inspector Raman (DeltaNu). Bench Raman dispersive microspectrometer (InVia Reflex, Renishaw) was used for comparative purposes. All spectra were obtained using a 785nm diode excitation. Although displaying lower spectral resolution comparing with the laboratory confocal instrument both portable instruments permit unambiguous detection of minerals in the field. These possibilities designate portable Raman machines as excellent tools for field geological applications. Miniaturised Raman instrument combined with LIBS will be included in the payload of the EXO Mars mission and would open interesting research possibilities in other in situ field planetary studies.

• MeSH
• amfibolový azbest analýza   MeSH
• arsenikové přípravky analýza   MeSH
• křemen analýza   MeSH
• minerály analýza   MeSH
• Ramanova spektroskopie přístrojové vybavení   metody   MeSH
• sulfidy analýza   MeSH
• uhličitan vápenatý analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• Názvy látek
• amfibolový azbest MeSH
• arsenic disulfide MeSH Prohlížeč
• arsenikové přípravky MeSH
• křemen MeSH
• minerály MeSH
• sulfidy MeSH
• tremolite MeSH Prohlížeč
• uhličitan vápenatý MeSH