Biostratigraphy and paleoecology of the Lower Cretaceous sediments in the Outer Western Carpathians (Silesian Unit, Czech Republic)

Almost black shale filling fissures in the Štramberk Limestone belonging to the Silesian Unit, Outer Western Carpathians contain prolific and poorly to moderately well preserved spores, pollen, organic-walled dinoflagellate cysts, foraminifers, and calcareous nannofossils. A detailed micropaleontological analysis of the proved stratigraphical interval from the Valanginian to the Albian indicated sedimentary conditions of brackish, restricted marine, shallow-marine and neritic sedimentation. Moreover, it drew attention to occasional influence from the Boreal province in the depositional area of the NW part of Tethys, especially during the Early Valanginian and Hauterivian, as supported by the presence of highlatitude nannofossils and organic-walled dinoflagellate cysts. Terrestrial miospores form a significant component of palynoassemblages and give evidence of continent proximity in the Valanginian-Barremian interval. Samples were acquired from isolated fissure fills in the Štramberk Limestone and, therefore, they do not represent a continuous section.Web of Science62433230

Efekti subhroničnog izlaganja zebrice, danio rerio sintetičkom mošusu

Policiklična jedinjenja sintetičkog mošusa su veoma rasprostranjena i koriste se u velikim količinama kao miris u proizvodima široke potrošnje. Zbog njihove česte upotrebe i otpuštanja mirisa, ova jedinjenja su postala prisutna svuda u životnoj sredini. Toksikološka istraživanja su potvrdila da jedinjenje mošusa predstavlja opasnost za vodene ekosisteme. Cilj ovog istraživanja bio je da se ocene efekti subhroničnog izlaganja sintetičkom mošusu tonalidu na rast riba i odgovore na oksidativni stress kod zebrice (Danio rerio). Test rasta kod mlađi zebrice izvršen je prema OECD metodu broj 215. U toku 28 dana, riba stara 30 dana je bila izložena koncentraciji tonalida (50; 500; 5.000 and 50.000 ng/l). Na kraju eksperimenta, sve ribe su žrtvovane, izmerene, određena je njihova specifična prosečna stopa rasta po tanku, a selektivni oksidativni stress markeri su analizirani u homogenatu celog tela (glutation S-transferaze, glutation reduktaze, glutation peroksidaze, katalaze i lipidne peroksidaze). U našem ekperimentu, nismo pronašli značajne razlike između kontrolne i eksperimentalne grupe u specifičnom prirastu, telesnoj težini i dužini. Međutim, primetili smo značajne promene kod većine oksidativnih stres markera naročito kod eksperimentalne grupe koja je bila izložena najvećoj koncentraciji mošusa (tonalida). U poređenju sa kontrolnom grupom, značajna povećanje je konstatovano u aktivnostima glutation S-transferaze (za koncentracije – 5.000 i 50.000 ng/l) i kataze (za koncentracije – 500, 5.000 i 50.000 ng/l). Sa druge strane, primećeno je značajno smanjenje aktivnosti glutation peroksidaze (za koncentraciju – 500 ng/l) u poređenju sa kontrolnom grupom. Nisu konstatovane promene u aktivnosti glutation reduktaze i nivou lipidne peroksidaze u poređenju sa kontrolnom grupom. Naši rezultati pokazuju da izlaganje zebrice tonalidinu ima značajan uticaj na oksidativne stres markere i enzime za detoksifikaciju. Promene u aktivnostima antioksidantnih enzima se mogu tumačiti kao adaptivni odgovor koji bi zaštitio organizam ribe od toksičnosti prouzrokovane tonalidinom

The measurement of reactive oxygen species in human neat semen and in suspended spermatozoa: a comparison

BACKGROUND: It is generally accepted that oxidative stress is an important factor in male infertility because it may impair the physiological function of spermatozoa at the molecular level. Nevertheless, although several approaches have been reported, the imbalance between production of reactive oxygen species (ROS) and activity of the antioxidant defense system in semen is difficult to investigate and remains poorly understood. METHODS: This study compares measurement of ROS production in neat semen and in washed spermatozoa obtained from the same ejaculate, and suspended in phosphate buffered saline using exactly the same luminol-mediated chemiluminescence method. Ninety one samples were obtained from males of infertile couples and 34 from volunteers with proven fertility. RESULTS: As expected, ROS levels were markedly lower in neat semen than in washed spermatozoa suspensions where seminal plasma with its potent antioxidant capacity was removed. In the cases of both neat semen and washed spermatozoa, ROS production was lowest in samples from normozoospermic males and highest in samples containing more than half million peroxidase-positive leukocytes per milliliter. For all samples, there was a significant positive correlation between ROS production by neat semen and that by washed spermatozoa suspension. CONCLUSION: Measurement of ROS production in neat semen better reflects actual oxidative status because it detects only the overproduction of ROS which are not effectively scavenged by antioxidant capacity of seminal fluid. The results of our study show a good commutability of both measurements for identification of semen samples with high ROS production. The measurement in neat semen is even less time consuming and therefore easier to implement into laboratory routine

The measurement of reactive oxygen species in human neat semen and in suspended spermatozoa: a comparison

Abstract Background It is generally accepted that oxidative stress is an important factor in male infertility because it may impair the physiological function of spermatozoa at the molecular level. Nevertheless, although several approaches have been reported, the imbalance between production of reactive oxygen species (ROS) and activity of the antioxidant defense system in semen is difficult to investigate and remains poorly understood. Methods This study compares measurement of ROS production in neat semen and in washed spermatozoa obtained from the same ejaculate, and suspended in phosphate buffered saline using exactly the same luminol-mediated chemiluminescence method. Ninety one samples were obtained from males of infertile couples and 34 from volunteers with proven fertility. Results As expected, ROS levels were markedly lower in neat semen than in washed spermatozoa suspensions where seminal plasma with its potent antioxidant capacity was removed. In the cases of both neat semen and washed spermatozoa, ROS production was lowest in samples from normozoospermic males and highest in samples containing more than half million peroxidase-positive leukocytes per milliliter. For all samples, there was a significant positive correlation between ROS production by neat semen and that by washed spermatozoa suspension. Conclusion Measurement of ROS production in neat semen better reflects actual oxidative status because it detects only the overproduction of ROS which are not effectively scavenged by antioxidant capacity of seminal fluid. The results of our study show a good commutability of both measurements for identification of semen samples with high ROS production. The measurement in neat semen is even less time consuming and therefore easier to implement into laboratory routine.</p

The Effects of Subchronic Exposure to Metribuzin on Danio rerio

The aim of this study was to assess the impact of metribuzin in surface waters on fish under experimental conditions. The effects of subchronic exposure to metribuzin on fish growth and the development of histopathological changes in selected organs (gill, kidney, liver) and on activity of some biochemical markers (CYP450, EROD) in Danio rerio were investigated during a 28-day toxicity test. Juvenile growth tests were performed on D. rerio according to OECD method number 215. Fish at an initial age of 30 days were exposed to a range of metribuzin concentrations (1.5, 5, 16, 33, and 53 mg L−1). Exposure to metribuzin at 53 mg L−1 was associated with increased mortality. Negative effects with regard to total body weight, length, and the inhibition of specific growth rate were induced at concentrations of 33 and 53 mg L−1. Histopathological examination revealed pathological lesions in the liver in pesticide-exposed fish only at the highest concentration of 53 mg L−1 of metribuzin. Based on the results of growth rate, biochemical markers (CYP450, EROD), and histopathological examination, the lowest observed effect concentration (LOEC) value was 33 mg L−1 and the no observed effect concentration (NOEC) value was 16 mg L−1

Evaluation of Biochemical, Haematological, and Histopathological Responses and Recovery Ability of Common Carp (Cyprinus carpio L.) after Acute Exposure to Atrazine Herbicide

The aim of study was to evaluate the effect of atrazine exposure (5, 15, 20, and 30 mg·L−1) on common carp and the ability of regeneration. During 96 h exposure we observed abnormal behavior in fish exposed to 20 and 30 mg·L−1. Mortality and histological alterations were noticed only in the group exposed to 30 mg·L−1. Most experimental groups showed significantly (P<0.05) lower values of haemoglobin, haematocrit, leukocyte, and lymphocyte and significantly higher values of monocytes, segmented and band neutrophile granulocytes, and also metamyelocytes and myelocytes. A significantly lower (P<0.05) leukocyte count was also recorded in experimental groups (5 and 15 mg·L−1) after recovery period. Statistically significant (P<0.05) alterations in glucose, total protein, lactate, phosphorus, calcium, and biopterin as well as in activities of ALT, AST, ALP, and LDH were found in most experimental groups. These changes were most apparent in the groups exposed to 20 and 30 mg·L−1. Most of the indices were found to be restored after the 7-day recovery period with the exception of LDH, ALT, and lactate in the group exposed to 15 mg·L−1. Our results showed that atrazine exposure had a profound negative influence on selected indices and also on histological changes of common carp