1-Hydroxypyrene–A Biochemical Marker for PAH Pollution Assessment of Aquatic Ecosystem

The aim of the present study was to assess aquatic contamination by polycyclic aromatic hydrocarbons (PAH), using the 1-hydroxypyrene (1-OHP) content in fish bile as a biochemical marker. A total of 71 chub (Leuciscus cephalus L.) were collected from seven locations on the Svitava and Svratka rivers in and around the industrial city of Brno, Czech Republic. The levels of 1-OHP were determined by reverse phase HPLC with fluorescence detection after deconjugation. Normalising the molar concentration of the biliary 1-OHP to the biliary protein content reduced sample variation. The content of 1-OHP was correlated with the PAH level in bottom sediment and semi-permeable membrane devices (SPMD), which was analyzed by a combination of HPLC/FLD and GC/MS methods. The highest mean values of 1-OHP were found in fish caught at the Svratka River at locations Modřice (169.2 ± 99.7 ng·mg−1 protein) and Rajhradice (152.2 ± 79.7 ng·mg−1 protein), which are located downstream from Brno. These values were significantly (P < 0.05) higher than those obtained from localities Kníničky (98.4 ± 66.1 ng·mg−1 protein) and Bílovice nad Svitavou (64.1 ± 31.4 ng·mg−1 protein). The lowest contents of PAH in sediment and SPMD were found at location Kníničky (1.5 mg·kg−1 dry mass and 19.4 ng·L−1, respectively). The highest contents of PAH in sediment and SPMD were found in Rajhradice (26.0 mg·kg−1 dry mass) and Svitava before junction (65.4 ng·L−1), respectively. A Spearman correlation test was applied to determine the relationship between biliary 1-OHP and the sum of PAH in sediment and SPMD. A positive, but no statistically significant correlation was found. The main impact sources of elevated level of PAHs in sites located downstream from Brno are most probably intensive industrial and agricultural activities and domestic waste

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

Influence of nationality on the Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS)

OBJECTIVE: In answer to the call for improved accessibility of neuropsychological services to the international community, the Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS; MS) was validated in multiple, non-English-speaking countries. It was created to monitor processing speed and learning in MS patients, including abbreviated versions of the Symbol Digit Modalities Test, California Verbal Learning Test, 2nd Edition, and the Brief Visuospatial Memory Test, Revised. The objective of the present study was to examine whether participant nationality impacts performance above and beyond common demographic correlates. METHOD: We combined published data-sets from Argentina, Brazil, Czech Republic, Iran, and the U.S.A. resulting in a database of 1,097 healthy adults, before examining the data via multiple regression. RESULTS: Nationality significantly predicted performance on all three BICAMS tests after controlling for age and years of education. Interactions among the core predictor variables were non-significant. CONCLUSION: We demonstrated that nationality significantly influences BICAMS performance and established the importance of the inclusion of a nationality variable when international norms for the BICAMS are constructed

Clinical correlates of grey matter pathology in multiple sclerosis

Traditionally, multiple sclerosis has been viewed as a disease predominantly affecting white matter. However, this view has lately been subject to numerous changes, as new evidence of anatomical and histological changes as well as of molecular targets within the grey matter has arisen. This advance was driven mainly by novel imaging techniques, however, these have not yet been implemented in routine clinical practice. The changes in the grey matter are related to physical and cognitive disability seen in individuals with multiple sclerosis. Furthermore, damage to several grey matter structures can be associated with impairment of specific functions. Therefore, we conclude that grey matter damage - global and regional - has the potential to become a marker of disease activity, complementary to the currently used magnetic resonance markers (global brain atrophy and T2 hyperintense lesions). Furthermore, it may improve the prediction of the future disease course and response to therapy in individual patients and may also become a reliable additional surrogate marker of treatment effect

Embryotoxicity of Selective Serotonin Reuptake Inhibitors—Comparative Sensitivity of Zebrafish (Danio rerio) and African Clawed Frog (Xenopus laevis) Embryos

Over the past twenty years, the prescription of antidepressant drugs has increased all over the world. After their application, antidepressants, like other pharmaceuticals, are excreted and enter the aquatic environment. They are dispersed among surface waters mainly through waste water sources, typically at very low concentrations— from a tenth up to hundreds of ng/L. Frequently detected antidepressants include fluoxetine and citalopram—both selective serotonin reuptake inhibitors. The aim of our study was to assess the embryotoxicity of fluoxetine hydrochloride and citalopram hydrochloride on the early life stages of zebrafish (Danio rerio) and the African clawed frog (Xenopus laevis). The embryos were exposed to various concentrations of the individual antidepressants and of their mixtures for 96 h. The tested levels included both environmentally relevant and higher concentrations for the evaluation of dose-dependent effects. Our study demonstrated that even environmentally relevant concentrations of these psychiatric drugs influenced zebrafish embryos, which was proven by a significant increase (p &lt; 0.01) in the embryos’ heart rates after fluoxetine hydrochloride exposure and in their hatching rate after exposure to a combination of both antidepressants, and thus revealed a potential risk to aquatic life. Despite these results, we can conclude that the African clawed frog is more sensitive, since exposure to the highest concentrations of fluoxetine hydrochloride (10,000 μg/L) and citalopram hydrochloride (100,000 μg/L) resulted in total mortality of the frog embryos

Towards exploiting change blindness for image processing

Change blindness is a type of visual masking which affects our ability to notice changes introduced in visual stimuli (e.g. change in the colour or position of an object). In this paper, we propose to use it as a means to identify image attributes that are less important than others. We propose a model of visual awareness based on low-level saliency detection and image inpainting, which identifies textured regions within images that are the most prone to change blindness. Results from a user study demonstrate that our model can generate alternative versions of natural scenes which, while noticeably different, have the same visual quality as the original. We show an example of practical application in image compression

The Effect of Mycotoxin Deoxynivalenol on Haematological and Biochemical Indicators and Histopathological Changes in Rainbow Trout (Oncorhynchus mykiss)

Deoxynivalenol (DON), produced by the Fusarium genus, is a major contaminant of cereal grains used in the production of fish feed. The effect of mycotoxin deoxynivalenol on rainbow trout (Oncorhynchus mykiss) was studied using a commercial feed with the addition of DON in a dose of 2 mg/kg feed. The fish (n=40) were exposed to the mycotoxin for 23 days. The trout were divided into two groups, control and experimental groups. Control groups were fed a commercial feed naturally contaminated with a low concentration of DON (225 μg/kg feed); experimental groups were fed a commercial feed with the addition of DON (1964 μg/kg feed). Plasma biochemical and haematological indices, biometric parameters, and histopathological changes were assessed at the end of the experiment. The experimental groups showed significantly lower values in MCH (P<0.05). In biochemical indices, after 23-day exposure, a significant decrease in glucose, cholesterol (P<0.05), and ammonia (P<0.01) was recorded in the experimental group compared to the control group. Our assessment showed no significant changes in biometric parameters. The histopathological examination revealed disorders in the caudal kidney of the exposed fish. The obtained data show the sensitivity of rainbow trout (O. mykiss) to deoxynivalenol

Adverse changes in cortical and trabecular bone compartments of the femur in rats with adjuvant-induced arthritis after one remodelling cycle

It is widely known that rheumatoid arthritis (RA) is associated with articular bone damage. However, there is still not enough information on whether the inflammatory process can deteriorate bone microstructure outside the joint as well. Furthermore, the impact of RA on the microscopic structure of cortical and trabecular bone, including parameters of bone microarchitecture, strength, and geometry after one remodelling cycle, has not been determined, yet. Therefore, this study investigated possible alterations in both cortical and trabecular bone compartments of the femur in a rat model of adjuvant-induced arthritis (AA) 28 days post disease induction. AA was generally evoked by a single intradermal injection ofsuspension of heat-inactivated Mycobacterium butyricumin incomplete Freund’s adjuvant. We have found that AA resulted in inflammation as evidenced by increased hind paw swelling, decreased levels of circulating albumin, and elevated levels of nitrite/nitrate, interleukin-1β. Detrimental changes in examined bone parameters related to microarchitecture, strength, and geometry were revealed in AA rats. Overall, AA was associated with bone loss, decreased bone mineral density in bothcortical and trabecular bone compartments, as well as reduced mechanical competence, and more intense vascularization in the cortical bone. According to our results, AA-related inflammation caused structural degradation of cortical and trabecular bone quality, as well as mechanical weakness in the femoral diaphysis leading to bone fragility after only one remodelling cycle. The findings focused on the femoral diaphysis, which is located outside the joint, are the first in this field of research