Impulsivity and the 5-HTTLPR Polymorphism in a Non-Clinical Sample

BACKGROUND: Impulsivity has been associated with serotonergic system functions. However, few researchers have investigated the relationship between a polymorphism in the promoter of the serotonin transporter gene (5-HTTLPR) and the different components of impulsivity in a non-clinical population. The aim of this study was to investigate the relationship between a polymorphism in the promoter region of the serotonin transporter gene (5-HTTLPR) and the different components of impulsivity in a non-clinical population. METHODOLOGY/PRINCIPAL FINDINGS: We administered two neuropsychological tests, the Continuous Performance Task and the Iowa Gambling Task, to 127 healthy participants to measure their levels of motor, attentional and non-planning impulsivity. Then, these participants were grouped by genotype and gender, and their scores on impulsivity measures were compared. There were no significant differences between group scores on attentional, motor and non-planning impulsivity. CONCLUSIONS/SIGNIFICANCE: Our results suggest that 5-HTTLPR genotype is not significantly associated with subsets of impulsive behavior in a non-clinical sample when measured by neuropsychological tests. These findings are discussed in terms of the sensitivity of neuropsychological tests to detect impulsivity in a non-clinical population and the role of gender and race in the relationship between the 5-HTTLPR and impulsivity

Status and management of noble crayfish

Noble crayfish Astacus astacus (L.) is an indigenous and the only crayfish species in Estonia. It is potentially endangered by invasion of alien species, diseases and habitat deterioration but does not have legal protected status and is fished only for recreational purpose. Crayfish Working Group of Ministry of Environment and Department of Aquaculture of the Estonian University of Life Sciences have developed crayfish conservation and management plan. Since 1994 standardized test fishing with traps (which catch only crayfish over 7 cm TL) has been carried out and database of these fishings shows, that crayfish is dwelling in more than 255 sites in the lakes, rivers, streams, artificial reservoirs. In 52% of monitored sites populations are weak, catch per trap night is below 1 specimen. Exceptionally rich is the stock on the island Saaremaa, where in 59% of populations catch per trap night is over 4 and can reach 50. Licensed recreational catch is allowed in regions, where monitoring data show good status of crayfish stock. It is not allowed to sell the crayfish caught on recreational license. Crayfishing season is limited with August, size limit in recreational fishery is 11 cm TL. There are 10 operating crayfish farms and 15 are under construction. The farms produce yearly around 1000 kg of commercial size crayfish for export to Finland. Over 200000 juveniles are produced for restocking yearly. Restocking projects e.g. restoration of populations, which have been lost because of plague have been successful. The main threat factor is crayfish plague. In 2006–2007 it destroyed the stock of crayfish farms of companies Veteko, Pähkla, Astacus and wild population of Põduste river on the island Saaremaa

Alterations of club cell activity in epidermis of common carp, Cyprinus carpio (Actinopterygii: Cypriniformes: Cyprinidae), due to infection by Ichthyophthirius multifiliis (Protista: Ciliophora)

Background. The abundance of club cells in epidermal tissue of fishes in the superorder Ostariophysi is a poorly understood phenomenon. Previous results have suggested that epidermal club cells have a generic role in response to injury and that they display intense phagocytotic activity, having an anti-parasitic function in the host. Earlier works suggested that club cells are usually located in the middle of the epidermis and that they do not communicate with the epidermal surface or do it only when the epidermis has been ruptured by predation. The presently reported study focused on the alterations of club cell activity in carp epidermis induced by ectoparasite, Ichthyophthirius multifiliis. We hoped that our observations would help to understand the function(s) of these cells. Materials and methods. This study was based on 200 four-month old common carp, Cyprinus carpio L., with mean body weight of 65 ± 5 g. The fish were experimentally infected with theronts of Ichthyophthirius multifiliis. In sequential days post infection, samples of fins and body skin were collected for histological and histochemical examination. The correlation between club cell densities and mucous cell densities was analysed using Pearson correlation analyses. Results. A local reduction of mucous cells occurred after theront invasion-induced proliferation, and increased club cell density around the parasite during the growth of trophonts. After parasites left the skin due to salt-water treatment, a decrease in the number of club cells was detected. During reinvasion the decrease in parasite activity in areas of club cells proliferation was not noted. It was found that giant mature club cells were opened on the surface. Conclusion. Club cells have no anti-parasitic function against I. multifiliis and these mature cells released their viscous secretion into water. The high density of club cells in the epidermis compensates an overall low density or absence of mucous cells. As it can be hardly concluded that the function of club cells is phagocytic removal of cell debris, an integrated research on mucosal immune mechanisms, as well as studies on epidermal tissue responses on product(s) released by club cells (“alarm substance cells”) should be carried out in the future

Alterations of club cell activity in epidermis of common carp, Cyprinus carpio (Actinopterygii: Cypriniformes: Cyprinidae), due to infection by Ichthyophthirius multifiliis (Protista: Ciliophora)

Background. The abundance of club cells in epidermal tissue of fishes in the superorder Ostariophysi is a poorly understood phenomenon. Previous results have suggested that epidermal club cells have a generic role in response to injury and that they display intense phagocytotic activity, having an anti-parasitic function in the host. Earlier works suggested that club cells are usually located in the middle of the epidermis and that they do not communicate with the epidermal surface or do it only when the epidermis has been ruptured by predation. The presently reported study focused on the alterations of club cell activity in carp epidermis induced by ectoparasite, Ichthyophthirius multifiliis. We hoped that our observations would help to understand the function(s) of these cells. Materials and methods. This study was based on 200 four-month old common carp, Cyprinus carpio L., with mean body weight of 65 ± 5 g. The fish were experimentally infected with theronts of Ichthyophthirius multifiliis. In sequential days post infection, samples of fins and body skin were collected for histological and histochemical examination. The correlation between club cell densities and mucous cell densities was analysed using Pearson correlation analyses. Results. A local reduction of mucous cells occurred after theront invasion-induced proliferation, and increased club cell density around the parasite during the growth of trophonts. After parasites left the skin due to salt-water treatment, a decrease in the number of club cells was detected. During reinvasion the decrease in parasite activity in areas of club cells proliferation was not noted. It was found that giant mature club cells were opened on the surface. Conclusion. Club cells have no anti-parasitic function against I. multifiliis and these mature cells released their viscous secretion into water. The high density of club cells in the epidermis compensates an overall low density or absence of mucous cells. As it can be hardly concluded that the function of club cells is phagocytic removal of cell debris, an integrated research on mucosal immune mechanisms, as well as studies on epidermal tissue responses on product(s) released by club cells (“alarm substance cells”) should be carried out in the future