Behavioral impacts of a mixture of six pesticides on rats

Pesticides can potentially contribute to the development of numerous neurodegenerative diseases. This study evaluates the effects of a six-pesticide mixture at doses around the no-observed-adverse-effectlevels (0 × NOAEL, control) and 0.25, 1 and 5 × NOAEL on behavior of Wistar rats. After 3, 6 and 12 months, rats were observed for neurobehavioral changes using the techniques of elevated plus maze and universal problemchamber, and the experiment was conducted thrice. The 3-month exposure revealed a decrease in the cognitive ability at the dose of 5 × NOAEL, and a dose-dependent research activity and anxiety. The 6-month exposurerevealed non-monotonic effects on the cognitive ability, with a decrease by 0.25 and 5 × NOAEL, as well as non-monotonic effects on anxiety, withan increase by 0.25 and 1 × NOAEL. A decrease was also observed in research activity at 5 × NOAEL. However, the 12-month exposure resulted to an increase in cognitive ability by 0.25 × NOAEL and in anxiety by 1 × NOAEL, as well as to a dose-dependent research activity. Repeating the trial showed that the cognitive ability increased from one trial to another, while the researching activity decreased and the anxiety increased by 0× NOAEL. In the groups exposed to pesticides mixture, the trends were different, showing that the exposure to pesticides combined with repeated trials, also influence the response of the animals. The resultsdemonstrate the occurrence of several dose-dependent behavioral responses, with negative effects occurring at doses that are considered safe. This study provides novel insights about time-dependent mixtures biology, and an important perspective to consider when conducting risk assessments.

Monitoring of environmental persistent organic pollutants in hair samples collected from wild terrestrial mammals of Primorsky Krai, Russia

Persistent organic pollutants (POPs) constitute a wide range of chemicals. Their release into the environment has raised great concern due to their potentially harmful impact in humans and wildlife species. The aim of this current study was to detect selected POPs in hair samples of wild terrestrial mammals from Primorsky Krai, Russia, so as to assess potential environmental exposure. The tested wild species were leopard cat, musk deer, wolf, amur hedgehog, and raccoon dog. The targeted organochlorines were hexachlorobenzene (HCB) and DDTs (opDDE, ppDDE, and opDDD), polychlorinated biphenyl (PCB) congeners (28, 52, 101, 118, 138, 153, and 180), and polycyclic aromatic hydrocarbons (PAHs) (acenaphylene (ACEN), fluorene (FLU), anthracene (ANTH) phenathrene (PHEN), and pyrene (PYR)). The detection of POPs was conducted in hair samples by a one-step hair extraction method, by using a headspace solid-phase microextraction technique (HS-SPME) and analyzed then by GC-MS. The majority of the wild animal hair samples were found positive in all tested pollutants. More specifically, the percentage of positive hair samples for HCB was 93.3% and for DDTs, PCBs, and PAHs, 20.0 to 100.0%, 6.7 to 100.0%, and 75.0 to 100.0%, respectively. DDT, PCB, and PAH detection ranged from 1.26 to 52.06 pg mg^-1, 0.73 to 31.34 pg mg^-1, and 2.59 to 35.00 pg mg^-1, respectively. The highest mean concentration levels of all tested pollutants were found for musk deer (PCBs 12.41 pg mg^-1, DDTs 21.87 pg mg^-1, PAHs 22.12 pg mg^-1) compared to the other wild species. To the best of our knowledge, this is the first study that provides results regarding contamination in different terrestrial mammals by POP exposure. The use of hair as a matrix is proven to be an effective tool for nondestructive biological monitoring of POP contamination in terrestrial ecosystems.

Development of the "rare-earth" hypothesis to explain the reasons of geophagy in Teletskoye Lake are kudurs (Gorny Altai, Russia)

The mineral and chemical composition of the liquid and lithogenous substances, consumed by the wild ungulate animals, at the kudurs of the Teletskoye Lake, Gorny Altai, Russia, was studied. It was investigated that all examined kudurits are argillous-aleurolitic and get in the interval from 1 to 100 μm with the predominance of the fraction 10 μm. By the mineral composition, the lithogenous kudurits present the quartz-feldspathic-hydromicaceous-chloritic mineral formations with the large content of the quartz particles (20-43%) and sodium-containing plagioclases (albite, 15-32 wt%). The lithogenous kudurits are the products of the reconstitution of the metamorphic cleaving stones as a result of the glacier abrasive effect, subsequent its aqueous deposits and then eolation in the subaerial conditions. The fontinal waters consumed at the kudurs are subsaline chloride-hydrocarbonate-sodium and sulphated-hydrocarbonate-calcium types. It essentially differs by the increased content of rare-earth elements in reference to the lake water. The acid (HCl, pH-1) extracts from the kudurits more actively extract calcium (10-35% of the gross contents; sodium extracts at the level of 1-3%). The most fluent in the microelements composition are Cu, Be, Sr, Co, Cd, Pb, Sc, Y and rare-earth elements. The transit of all these elements into the dissoluted form fluctuates about 10% from the gross contents. The reason of geophagy is related to tendency of herbivores to absorb mineralized subsoils enriched by the biologically accessible forms of rare-earth elements, arisen as a result of vital activity of specific microflora.

A guide to acquired vitamin K coagulophathy diagnosis and treatment: the Russian perspective

Abstract

Physicians often come across with cases of vitamin K antagonists–dependent coagulopathy for reasons such as accidental use of the vitamin K antagonists (VKA), excessive administration of prescribed anticoagulants of indirect action or not reported administration of vitamin K antagonists due to memory impairment and/or other mental disorders, even deliberate use thereof (attempt to murder or suicide). Rodenticide-poisoning (coumarins, warfarins) via food or occupational accidents are difficult to diagnose. This article discusses different types of acquired vitamin K-dependent coagulopathy. Differential diagnosis is primarily based on patient statements before additional causes of vitamin K deficiency are explored. Even when pathological vitamin K deficiency is not determined, appropriate and urgent medical treatment is necessary: administration of fresh frozen plasma or concentrated factors of the prothrombin complex, administration of vitamin K remedies along with symptomatic therapy. With early diagnosis and prescription of appropriate therapy, prognosis is favorable.

Graphical abstract

Reasons for vitamin K antagonists–dependent coagulopathy cases

Influence of multi-walled carbon nanotubes on the cognitive abilities of Wistar rats

Studies of the neurobehavioral effects of carbon nanomaterials, particularly those of multi-walled carbon nanotubes (MWCNTs), have concentrated on cognitive effects, but data are scarce. The aim of this study was to assess the influence of MWCNTs on a number of higher nervous system functions of Wistar rats. For a period of 10 days, two experimental groups were fed with MWCNTs of different diameters (MWCNT-1 group, 8-10 nm; MWCNT-2 group, 18-20 nm) once a day at a dosage of 500 mg/kg. In the open-field test, reductions of integral indications of researching activity were observed for the two MWCNT-treated groups, with a parallel significant (P<0.01) increase in stress levels for these groups compared with the untreated control group. In the elevated plus-maze test, integral indices of researching activity in the MWCNT-1 and MWCNT-2 groups reduced by day 10 by 51 and 62%, respectively, while rat stress levels remained relatively unchanged. In the universal problem solving box test, reductions in motivation and energy indices of researching activity were observed in the two experimental groups. Searching activity in the MWCNT-1 group by day 3 was reduced by 50% (P<0.01) and in the MWCNT-2 group the relevant reduction reached 11.2%. By day 10, the reduction compared with controls, was 64% (P<0.01) and 58% (P<0.01) for the MWCNT-1 and MWCNT-2 groups, respectively. In conclusion, a series of specific tests demonstrated that MWCNT-treated rats experienced a significant reduction of some of their cognitive abilities, a disturbing and worrying finding, taking into consideration the continuing and accelerating use of carbon nanotubes in medicine and science.

Multi-walled carbon nanotubes increase anxiety levels in rats and reduce exploratory activity in the open field test

The results of the first study on the effects of multi-walled carbon nanotubes (MWNTs) on the exploratory activity and the emotional state in laboratory rats assessed by the open field test are reported. During three or ten days, rats received 8-10 nm MWNTs added to their food at a dose of 500 mg/kg. It was demonstrated that, in the group of rats which were fed with MWNTs, the integrated anxiety level index began to increase as early as the third day of the experiment; on the tenth day, it appeared to be twice increased. It was also demonstrated that MWNTs decreased the integrated exploratory activity index nearly twofold on the third day and nearly fourfold on the tenth day.

Biological activity of some derivatives of β-cyclodextrin

New compounds of β-cyclodextrin containing covalently bound (conjugated) residues of acetylsalicylic and 1-(4-isobutylphenyl)-propionic acids were synthesized in the reaction of chlorides of the corresponding acids with β-cyclodextrin. We studied antiplatelet and antiphlogistic properties of these substances. It was shown that new compounds are comparable and in some cases are superior to the reference drugs acetylsalicylic acid and ibuprofen by anti-inflammatory and antiaggregant activities.

[Action motor food of behaviour in modular device]

The technique for studying of the got behaviour at laboratory animals is offered. The corrective influence of high doses of Piracetam is shown on the example of aimed motor food runnings which contribute to food reguiments. Primary differences of the modular device in comparison with the "Colombian" chamber are noted.

[Typological features of behaviour in rats]

Existence of internal correlations among parameters of the exploratory and purposive searching activity and the level of anxiety in rats were revealed. Individual parameters of exploratory activity and anxiety were measured by means of classical procedures of the open field and elevated plus maze. The resulting of purposeful search activity was studied with methods designed by ourselves, in universal problem-solving chamber. Cluster analysis has revealed hierarchical groups in populations with cognate quantitative-qualitative behavioural signs.