Editorial: Neuroplasticity and Extracellular Proteolysis

Neuroplasticity refers to the ability of the Central Nervous System (CNS) to alter its structure and function in response to a variety of physiological and pathological processes such as development, cognition, injury or neurological diseases. Since more than four decades, studies on synaptic plasticity in the context of memory and learning attracted a remarkable interest. Soon after first seminal works on synaptic plasticity were published, research in this field was extended by studies on non-synaptic as wells as structural plasticity towards a goal to understand cellular and molecular determinants of cognition. Over the past two decades, yet two additional crucial players in neuroplastic phenomena started to be intensely investigated – glial cells and the extracellular matrix (ECM). Growing awareness that glial cells, especially astrocytes, are important regulators of synaptic functions gave rise to a novel concept of a tri-partite synapse. Also, over the last two decades, a growing body of evidence has accumulated that the extracellular matrix (ECM) in the brain is strongly involved in regulation of neurons, in particular, in synaptic plasticity. Thus, a concept of tetra-partite synapse was put forward by some neuroscientists. The cross-talk between neuron-glia-ECM system involves enzymatic degradation of proteins or peptides and amino acids occurring in each of these brain constituents by means of a variety of proteases. Importantly, it has been realized that proteases such as serine proteases and matrix metalloproteinases, not only accompany “robust” phenomena such as cell division, or development or neurodegnerative conditions but may play a very subtle signaling functions, particularly important in memory acquisition. Indeed, the repertoire of substrates for these enzymes covers a wide variety of proteins known to play important role in the neuroplastic phenomena (e.g. BDNF, TNF-a, ephrin systems, various cell adhesion molecules, etc.). In result, the role of metalloproteinases and such serine proteases as tissue plasminogen activator (tPA), neuropsin or neurotrypsin in synaptic plasticity as well as in learning and memory has been particularly well demonstrated. It needs to be emphasized, however, that in spite of a remarkable progress in this field, several basic questions regarding molecular and cellular mechanisms remain unanswered. Potential involvement of so many important players (various proteases and their substrates in neurons, glia and in ECM) points to an enormous potential for plasticity phenomena but makes also studies into underlying mechanisms particularly difficult. In the proposed Research Topic we provide both review of the current state of the art and present some original reports on specific aspects of the role of proteolysis in neuroplasticity phenomena. The present ebook starts with extensive reviews describing involvement of proteolysis not only in synaptic plasticity but also in regulating endogenous excitability and structural changes at the network, cellular and subcellular levels. Cross-talk between neuroplasticity and proteolysis is also emphasized in the context of development and in relation to various pathologies. Whereas in the first part of the present ebook, the major focus is on metalloproteinases, the successive articles address the role of neuropsin and thrombin. The Research Topic is concluded with a series of articles describing the components of extracellular matrix and adhesion proteins and their elaboration by mechanisms dependent directly or indirectly on proteolysis. We do hope that the present ebook will further stimulate the interest in the fascinating investigations into neuroplasticity-proteolysis cross-talk

Reception of subjectivity of critical theory and Machiavellianism : a proposal for computer aided diagnosis of pathology in education

The authors of this paper, while observing the Polish education system, can not accept the ossified administrative structures existing in the system and the triumph of economic objectives over the human ones, the latter understood as individuals having the opportunity for self-realisation (developing one's subjectivity). We want to ask what identities an education system functioning in this way would create? A lot of attention is devoted in the literature to the problem of education. We also want to speak on this matter, for the sake of the common good which education undoubtedly is. We sincerely hope that the perception of problems in the system will lead to its repair and not its destruction. This paper consists of two main parts. The first part presents the reconstruction of critical theory based on the philosophy of Theodor Adorno, Max Horkheimer and Jurgen Habermas, which concerns the concept of subjectivity. The notion of subjectivity emerging from the thoughts of the representatives of the Frankfurt School is then confronted with the image of man created by the Machiavellian thought, according to social sciences. This is followed by a description of the Machiavellian personality trait, based on the psychological interpretation of Machiavellianism, and not on the current philosophical interpretation. In the second part, the authors present the proposal for using computer exploration methods to identify Machiavellian behaviours. The proposed solution takes into account cognitive, educational and preventive aspects

Pathophysiology of Trans-Synaptic Adhesion Molecules: Implications for Epilepsy

Chemical synapses are specialized interfaces between neurons in the brain that transmit and modulate information, thereby integrating cells into multiplicity of interacting neural circuits. Cell adhesion molecules (CAMs) might form trans-synaptic complexes that are crucial for the appropriate identification of synaptic partners and further for the establishment, properties, and dynamics of synapses. When affected, trans-synaptic adhesion mechanisms play a role in synaptopathies in a variety of neuropsychiatric disorders including epilepsy. This review recapitulates current understanding of trans-synaptic interactions in pathophysiology of interneuronal connections. In particular, we discuss here the possible implications of trans-synaptic adhesion dysfunction for epilepsy

A Methodology of Orthopaedic Measurement Arm Workspace Determination.

This paper outlines general assumptions of work principle of displacement measuring arm that bases on accelerometers. Symbolic representation of arm’s kinematic structure is shown. Also, an analysis of construction correctness has been verified in terms of the effectiveness of using accelerometers to measure individual links displacements. A method of acquiring information on workspace is presented. The workspace has been determined in two variants: without considering last link orientation and for given orientation of that link. Paper also describes a determination method of increments values of angular displacements for individual links of the arm in terms of obtained proper results and rational computation time of workspace scanning algorithm. Finally, there is a presentation of method for determining a cuboid space for arm accuracy and repeatability measurement in XYZ coordinate system

Wrist arthroplasty, good alternative for rheumatoid wrist: Case report with literature review

Within the hand, the wrist is the most affected joint by rheumatoid arthritis (RA). Wrist fusion (WF) and wrist arthroplasty (WA) are solutions for severe arthritis of the wrist. WA decreases pain, and, contrary to WF, preserves motion. Reported clinical results of modern prosthesis constructs are good and the patients are satisfied. This research presents a patient with RA treated with WA. The follow-up is 13 years. There were 2 further synovectomies. Some bone erosion was observed. Apart from that, the patient is satisfied with WA. It seems that WA should be considered earlier in the treatment scheme in patients with RA

Trajectory Tracking Control of a Mobile Robot with the ROS System

This article provides a simulation and laboratory study of a control system for a two-wheeled differential-drive mobile robot with ROS system. The authors propose an approach to designing a control system based on a parametric model of the robots dynamics. The values of unknown parameters of the dynamic model have been determined by means of a Levenberg-Marguardt identification method. By comparing the desired trajectories with those obtained from simulation and laboratory tests, and based on errors analysis, the correctness of the model parameter identification process and the control system operation was then determined

Mice with ablated adult brain neurogenesis are not impaired in antidepressant response to chronic fluoxetine

The neurogenesis hypothesis of major depression has two main facets. One states that the illness results from decreased neurogenesis while the other claims that the very functioning of antidepressants depends on increased neurogenesis. In order to verify the latter, we have used cyclin D2 knockout mice (cD2 KO mice), known to have virtually no adult brain neurogenesis, and we demonstrate that these mice successfully respond to chronic fluoxetine. After unpredictable chronic mild stress, mutant mice showed depression-like behavior in forced swim test, which was eliminated with chronic fluoxetine treatment, despite its lack of impact on adult hippocampal neurogenesis in cD2 KO mice. Our results suggest that new neurons are not indispensable for the action of antidepressants such as fluoxetine. Using forced swim test and tail suspension test, we also did not observe depression-like behavior in control cD2 KO mice, which argues against the link between decreased adult brain neurogenesis and major depression

AAV-Tau Mediates Pyramidal Neurodegeneration by Cell-Cycle Re-Entry without Neurofibrillary Tangle Formation in Wild-Type Mice

In Alzheimer's disease tauopathy is considered secondary to amyloid, and the duality obscures their relation and the definition of their respective contributions

The impact of carotid intima - media complex index selection for the investigation of a correlation with chosen cardiovascular risk factors

Wstęp Ultrasonograficzna ocena IMT (intima-media thickness) w ścianie tętnicy szyjnej znajduje obecnie powszechne zastosowanie w badaniach klinicznych. Wielokrotnie potwierdzano, że zwiększona grubość kompleksu IMT jest cennym wskaźnikiem wystąpienia powikłań sercowo-naczyniowych. W publikowanych pracach występują jednak różne parametry opisujące IMT i nie ma jednomyślności co do przewagi któregoś z nich. Celem niniejszego badania było wskazanie różnic w zależnościach między różnymi wskaźnikami IMT a wybranymi czynnikami ryzyka sercowo-naczyniowego. Materiał i metody Badaniami objęto grupę 90 mężczyzn (wiek 46 &#177; 8 lat, BMI 27,7 &#177; 3,6 kg/m2, ciśnienie tętnicze 129 &#177; 8/81 &#177; 7 mm Hg, ABPM: SBP - 125,9 &#177; 7,9; DBP - 79,7 &#177; 6,3, stężenie cholesterolu całkowitego 237 &#177; 35,7 mg/dl, cholesterolu frakcji HDL 52 &#177; 13, triglicerydów 184 &#177; 99). U każdego pacjenta wykonano badanie echokardiograficzne serca z oceną funkcji skurczowej i rozkurczowej lewej komory. Pomiary IMT w ścianie tętnicy szyjnej wykonano za pomocą specjalistycznego oprogramowania analizującego cyfrowe obrazy ścian tętnic szyjnych. Uwzględniono zarówno średnią, jak i maksymalną IMT, pole powierzchni przekroju IMT (CSA-IMT), jak i wartości względne. Zależności między IMT a wybranymi czynnikami ryzyka sercowo- naczyniowego badano za pomocą analizy regresji wielokrotnej. Wyniki Stwierdzono najwyższe wskaźniki regresji wielokrotnej dla względnej średniej IMT (r = 0,689) i względnego CSA-IMT (r = 0.685). Relatywna średnia IMT była determinowana przez: wiek (p < 0,001), stężenie cholesterolu frakcji HDL (p = 0,02) oraz częstość akcji serca ocenianą w okresie nocy (p = 0,035). Względne CSA-IMT było determinowane przez: wiek (p < 0,001), stężenie cholesterolu frakcji HDL (p = 0,02), częstość akcji serca ocenianą w okresie nocy (p = 0,025), poziom glikemii na czczo (p = 0,021) oraz BMI (p = 0,045). Wnioski Względne CSA-IMT wśród innych parametrów opisujących IMT może być najlepszym wskaźnikiem ryzyka sercowo-naczyniowego. Ocena tego parametru może prowadzić do bardziej precyzyjnej oceny całkowitego ryzyka sercowo-naczyniowego.Nadciśnienie Tętnicze 2007, tom 11, nr 4, strony 335&#8211;349.Background Carotid intima-media thickness (IMT) is widely used in clinical research. There is strong evidence that increased IMT is a powerful predictor of cardiovascular complications. Varies indices of IMT are used in different studies. So far there is no agreement which marker best reflects cardiovascular risk. Therefore the aim of the study was to establish the association between chosen cardiovascular risk factors and different indices of IMT. Material and methods 90 males (mean age: 46 &#177; 8 yrs, BMI 27.7 &#177; 3.6 kg/m2, office blood pressure 129 &#177; 8/81 &#177; 7 mm Hg, 24-hour ambulatory blood pressure: SBP - 125.9 &#177; 7.9; DBP: 79.7 &#177; 6.3, total cholesterol 237 &#177; 35.7 mg/dl, HDL 52 &#177; 13, TG 184 &#177; 99) were studied. Doppler echocardiography with systolic and diastolic function evaluation was performed using ALOKA 5000 machine. CIMT measurement was obtained by analysis of ultrasonographic images with dedicated software. Varies indices of common carotid intima&#8211;media complex including average IMT, maximal IMT, average cross-sectional area of IMT (CSA-IMT), relative average IMT, relativemaximal IMT and relative CSA-IMT were calculated. The relationship between traditional risk factors and indices of IMT was analyzed by means of multiple regression. Results The analysis revealed the highest MR coefficients for relative average IMT (R = 0.689) and relative CSAIMT (R = 0.685). Relative average IMT was significantly determined by age (p < 0.001), HDL-cholesterol level (p = 0.02) and 24-ABPM night heart rate (p = 0.035). Relative CSA-IMT was significantly determined by age (p < 0.001), HDL-cholesterol level (p = 0.02), 24-ABPM night heart rate (p = 0.025), BMI (p = 0.045) and fasting glucose level (p = 0.021). Conclusions Among varies common carotid IM indices relative CSA-IMT may be the best marker of cardiovascular risk. Assessment of this variable may lead to a more precise stratification of the global cardiovascular risk. Arterial Hypertension 2007, vol. 11, no 4, pages 335-349