24 research outputs found
Behavioral characteristics as potential biomarkers of the development and phenotype of epilepsy in a rat model of temporal lobe epilepsy
The present study performed a detailed analysis of behavior in a rat model of epilepsy using both established and novel methodologies to identify behavioral impairments that may differentiate between animals with a short versus long latency to spontaneous seizures and animals with a low versus high number of seizures. Temporal lobe epilepsy was induced by electrical stimulation of the amygdala. Rats were stimulated for 25 min with 100-ms trains of 1-ms biphasic square-wave pluses that were delivered every 0.5 s. Electroencephalographic recordings were performed to classify rats into groups with a short latency ( 20 days, n = 8) to the first spontaneous seizure and into groups with a low number of seizures (62 ± 64.5, n = 8) and high number of seizures (456 ± 185, n = 7). To examine behavioral impairments, we applied the following behavioral tests during early and late stages of epilepsy: behavioral hyperexcitability, open field, novel object exploration, elevated plus maze, and Morris water maze. No differences in stress levels (e.g., touch response in the behavioral hyperexcitability test), activity (e.g., number of entries into the open arms of the elevated plus maze), or learning (e.g., latency to find the platform in the Morris water maze test during training days) were observed between animals with a short versus long latency to develop spontaneous seizures or between animals with a low versus high number of seizures. However, we found a higher motor activity measured by higher number of entries into the closed arms of the elevated plus maze at week 26 post-stimulation in animals with a high number of seizures compared with animals with a low number of seizures. The analysis of the Morris water maze data categorized the strategies that the animals used to locate the platform showing that the intensity of epilepsy and duration of epileptogenesis influenced swimming strategies. These findings indicate that behavioral impairments were relatively mild in the present model, but some learning strategies may be useful biomarkers in preclinical studies
International Innovation Cooperation with a View to Innovative Development
Currently the process of globalization in the field of scientific, technical
and industrial activity continues to grow. Countries conclude bilateral and
multilateral agreements to facilitate cooperation in scientific research and
co-financing of capital-intensive innovation projects. Combining competitive
advantages of companies is motivated by the government’s policy with
respect to attracting foreign direct investments and entering new markets.
Despite some discomfort of countries of the world caused by the outflow of
knowledge abroad and disturbance of the equilibrium of the trade balance,
most of the countries of the OECD have scientific and economic benefits from
these transactions. The processes associated with innovations are constantly
in the focus of attention of local and foreign experts and are reflected in
their works. The aim of the article is to analyze the impact of international
integration interaction of countries of the world on innovative development.
The forms of internationalization of innovation activities have been analyzed.
The main vector of the modern global competition based on scientific
and technological achievements and innovations has been determined. The
main directions of the internationalization of innovation activities have been
revealed and justifie
New hippocampal neurons are not obligatory for memory formation; cyclin D2 knockout mice with no adult brain neurogenesis show learning
The role of adult brain neurogenesis (generating new neurons) in learning and memory appears to be quite firmly established in spite of some criticism and lack of understanding of what the new neurons serve the brain for. Also, the few experiments showing that blocking adult neurogenesis causes learning deficits used irradiation and various drugs known for their side effects and the results obtained vary greatly. We used a novel approach, cyclin D2 knockout mice (D2 KO mice), specifically lacking adult brain neurogenesis to verify its importance in learning and memory. D2 KO mice and their wild-type siblings were tested in several behavioral paradigms, including those in which the role of adult neurogenesis has been postulated. D2 KO mice showed no impairment in sensorimotor tests, with only sensory impairment in an olfaction-dependent task. However, D2 KO mice showed proper procedural learning as well as learning in context (including remote memory), cue, and trace fear conditioning, Morris water maze, novel object recognition test, and in a multifunctional behavioral system-IntelliCages. D2 KO mice also demonstrated correct reversal learning. Our results suggest that adult brain neurogenesis is not obligatory in learning, including the kinds of learning where the role of adult neurogenesis has previously been strongly suggested
The possibilities of dentition reconstruction with the use of bicortical implants : review of literature
Współcześnie implantologia stanowi podstawową metodę
zaopatrzenia protetycznego pacjentów z brakami zębowymi,
umożliwiając zarówno rehabilitację, jak i rekonstrukcję
protetyczną. Implanty cechują się przede wszystkim biozgodnością
oraz rozmaitym zastosowaniem klinicznym (wykorzystanie
zarówno jako filarów pod prace stałe, jak i do wzmocnienia
retencji protez ruchomych). Obok powszechnie stosowanych
implantów śródkostnych bazowanych na systemie Brånemarka
swoje miejsce znalazły również implanty bikortykalne, oparte
o dwie blaszki istoty zbitej, co warunkuje odmienności biomechaniczne
oraz kliniczne pracy z tego typu wszczepami. Mogą
być one stosowane do odbudowy braków zębowych o rozmaitej
etiologii (choroba próchnicowa, periodontopatie, urazy) z bardzo
dobrą skutecznością i stanowią alternatywę dla tradycyjnych
systemów implantologicznych.Nowadays, implantology is the basic metod of prosthetic
supply of patients with dental deficiencies. It enables both
prosthodontic rehabilitation and reconstruction. Implants are
primarly biocompatible and of vast clinical application (both
as pillars for fixed prosthesis and as an additional retention for
mobile ones). Besides the commonly used intraosseus implants
based on Brånemark’s system, bicortical implants were brought
to stomatology. Since they rest on both layers of lamina dura,
their biomechanics as well as clinical approach differs. They can
be used to reconstuct teeth loss of a variety of aetiology (caries,
periodontitis, traumas) with very high efficacy and constitute an
alternatice to traditional implant systems
MicroRNA loss enhances learning and memory in mice
Dicer-dependent noncoding RNAs, including microRNAs (miRNAs), play an important role in a modulation of translation of mRNA transcripts necessary for differentiation in many cell types. In vivo experiments using cell type-specific Dicer1 gene inactivation in neurons showed its essential role for neuronal development and survival. However, little is known about the consequences of a loss of miRNAs in adult, fully differentiated neurons. To address this question, we used an inducible variant of the Cre recombinase (tamoxifen-inducible CreERT2) under control of Camk2a gene regulatory elements. After induction of Dicer1 gene deletion in adult mouse forebrain, we observed a progressive loss of a whole set of brain-specific miRNAs. Animals were tested in a battery of both aversively and appetitively motivated cognitive tasks, such as Morris water maze, IntelliCage system, or trace fear conditioning. Compatible with rather long half-life of miRNAs in hippocampal neurons, we observed an enhancement of memory strength of mutant mice 12 weeks after the Dicer1 gene mutation, before the onset of neurodegenerative process. In acute brain slices, immediately after high-frequency stimulation of the Schaffer collaterals, the efficacy at CA3-to-CA1 synapses was higher in mutant than in control mice, whereas long-term potentiation was comparable between genotypes. This phenotype was reflected at the subcellular and molecular level by the elongated filopodia-like shaped dendritic spines and an increased translation of synaptic plasticity-related proteins, such as BDNF and MMP-9 in mutant animals. The presented work shows miRNAs as key players in the learning and memory process of mammals