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    Slawomir Wójcik

    Hypercholesterolemia affects the neurovascular unit, including the cerebral blood vessel endothelium. Operation of this system, especially in the context of energy metabolism, is controlled by extracellular concentration of purines,... more
    Hypercholesterolemia affects the neurovascular unit, including the cerebral blood vessel endothelium. Operation of this system, especially in the context of energy metabolism, is controlled by extracellular concentration of purines, regulated by ecto-enzymes, such as e-NTPDase-1/CD39, ecto-5′-NT/CD73, and eADA. We hypothesize that hypercholesterolemia, via modulation of the activity of nucleotide metabolism-regulating ecto-enzymes, deteriorates glycolytic efficiency and energy metabolism of endothelial cells, which may potentially contribute to development of neurodegenerative processes. We aimed to determine the effect of hypercholesterolemia on the concentration of purine nucleotides, glycolytic activity, and activity of ecto-enzymes in the murine brain microvascular endothelial cells (mBMECs). We used 3-month-old male LDLR−/−/Apo E−/− double knockout mice to model hypercholesterolemia and atherosclerosis. The age-matched wild-type C57/BL6 mice were a control group. The intracellu...
    The glial cells play an important role in pathophysiology of the intracerebral haemorrhage (ICH). Thus the attempt at evaluating the possible influence of the propofol on the reactivity of astro- and microglial cells in the course of ICH... more
    The glial cells play an important role in pathophysiology of the intracerebral haemorrhage (ICH). Thus the attempt at evaluating the possible influence of the propofol on the reactivity of astro- and microglial cells in the course of ICH was performed. 50 rats were divided into two groups depending on the applied anaesthesia. All animals were generally anaesthetized with fentanyl, dehydrobenzperidol and midazolam. No additional agents were given to the animals of the control group (group I). In the experimental group (group II), the animals received additionally intraperitoneally propofol in a dose of 50 mg/kg every thirty minutes. ICH was produced through infusion of the blood into the striatum. The astrocytic and microglial cells population was assessed on the 1, 3, 7, 14 and 21 days after producing a haematoma using antibodies anti-GFAP and OX42. The stereological analysis was applied to estimate the numerical density of immunoreactive cells and the distribution of their types. On the 14th and 21st days of observation the density of GFAP-immunoreactivity (ir) cells was significantly higher in group II than that in group I. There were no differences in percentage distribution of GFAP-ir astrocytes between group I and group II. On the 3rd, 14th and 21st days of observation the density of OX42-ir cells was higher in group II in comparison with group I. For the 7th, and 21st days of survival the percentage of the ameboid form of OX42-ir cells was significantly lower in group I than that in group II. The administration of propofol during anaesthesia in the animals with ICH has evoked an increase of the activation of the astro- and microglial cells.
    Immunohistochemical study of the cholinergic innervation of the hippocampal calretinin-containing cells was conducted on 28 rat brains of postnatal ages: P0, P4, P7, P14, P21, P30 and P60. Sections with double immunostaining for vesicular... more
    Immunohistochemical study of the cholinergic innervation of the hippocampal calretinin-containing cells was conducted on 28 rat brains of postnatal ages: P0, P4, P7, P14, P21, P30 and P60. Sections with double immunostaining for vesicular acetylcholine transporter (VAChT; the marker of cholinergic cells, fibres and terminals) and calretinin were analysed using confocal laser-scanning microscope. Obtained data demonstrate that during development as well as in adult species calretinin-containing neurones in the rat hippocampus form sparse synaptic contact with VAChT-ir terminals. It seems probable that cholinergic innervation is not crucial for the functioning of CR-ir cells--probably they remain under the greater influence of a system other than the cholinergic system.
    The piriform cortex (PC), the primary olfactory cortex, is involved in the processes of learning and stress response and possibly plays an important role in epileptogenic activity. The results of several recent studies suggest that those... more
    The piriform cortex (PC), the primary olfactory cortex, is involved in the processes of learning and stress response and possibly plays an important role in epileptogenic activity. The results of several recent studies suggest that those PC neurons that contain neuronal nitric oxide synthase (nNOS) may play a key role during spatial learning and in the modulation of initiation, propagation and generalisation of seizures in various experimental models and may influence neuronal vulnerability after epileptic insults. The aim of this study was to characterise the pattern of distribution and morphology of nNOS-immunoreactive elements in PC of the adult rabbit. The co-localisation of nNOS and calretinin (CR) was also studied. The pattern of nNOS-ir within the rabbit PC is similar to that described previously in other mammals. The morphology of nNOS-ir elements, namely varicose fibres and Cajal-Retzius cells, suggest that NO has an important influence on PC function. Surprisingly, in the rabbit PC nNOS-ir elements show a very low level of co-localisation with CR-ir.
    The piriform cortex has been extensively studied due to its possible role in epileptogenic activity. Neurones containing calcium-binding proteins (CaBPs), as a component of inhibitory circuitry, seem to be critically involved in this... more
    The piriform cortex has been extensively studied due to its possible role in epileptogenic activity. Neurones containing calcium-binding proteins (CaBPs), as a component of inhibitory circuitry, seem to be critically involved in this pathological process. The aim of the present study was to characterise the pattern of distribution of CaBPs-immunoreactivity in the piriform cortex of the adult rabbit. It comprises labelled cells, fibres (often with varicosities) and terminals. It varies among the layers. Moreover, the distribution of the parvalbumin- and calretinin-immunoreactive fibres and terminals allows even further subdivision of the layer I into two sublayers. Calretinin-ir neurones are located in subpial (Ia) layer, while parvalbumin - as well as calbindin-D28k-ir ones are mainly located in the second and third layer. Cajal-Retzius-like neurones containing calretinin, Chandelier cells containing parvalbumin and basket cells containing calbindin D28k and parvalbumin can be distinguished among labelled subpopulations of CaBPs neurones. In general, the pattern of PV- CR- and CB-immunoreactivity is similar to that previously characterised in other mammals, i.e., rats, guinea pigs, hedgehog, and tenrecs. The pattern is organised in topographic fashion confirming the complexity of regulatory circuits in the rabbit piriform cortex.
    Immunohistochemical study of the cholinergic innervation of the parvalbumin- and calbindin-containing cells in the hippocampus was conducted on 30 rat brains of various postnatal ages: P0, P4, P7, P14, P21, P30, P60 and P180. Sections... more
    Immunohistochemical study of the cholinergic innervation of the parvalbumin- and calbindin-containing cells in the hippocampus was conducted on 30 rat brains of various postnatal ages: P0, P4, P7, P14, P21, P30, P60 and P180. Sections with double immunostaining for vesicular acetylcholine transporter (VAChT; the marker of cholinergic cells, fibres and terminals) and parvalbumin (PV) or calbindin (CB) were analysed using confocal laser-scanning microscope. Obtained data demonstrate that the pattern of cholinergic innervation of calbindin- and parvalbumin-immunoreactive hippocampal neurones shows some differences. During development as well as in the adult species cholinergic terminals preferentially innervate CB-containing neurones, while cholinergic terminals on PV-containing cells were observed rarely. Cholinergic endings on the CB-ir neurones are localised both on their somata and dendrites, whereas on PV-ir cells they form synaptic contact predominantly with processes. In spite of the unquestionable cholinergic influence particularly on CB-ir cells, the number of cholinergic endings suggests that this input seems not to be crucial for the activity of the studied cell populations.
    An immunocytochemical double-staining method was applied in order to study the co-localisation of nitric oxide synthase (NOS) with three calcium-binding proteins, calbindin D28k (CB), calretinin (CR) and parvalbumin (PV) in the claustrum... more
    An immunocytochemical double-staining method was applied in order to study the co-localisation of nitric oxide synthase (NOS) with three calcium-binding proteins, calbindin D28k (CB), calretinin (CR) and parvalbumin (PV) in the claustrum of the rat during the first 4 months of life (postnatal days: PO-P120). The co-localisation of NOS/PV and NOS/CB is reported. These neurons fall into the category of non-pyramidal cells. Double-labelled NOS/CB neurons are observed in the claustrum starting from P4, whereas double-labelled NOS/PV neurons are observed from P14 onwards. The percentages of double-labelled neurons increase in relation to the age. Double-labelled NOS/CB and NOS/PV neurons, although they do not constitute a numerous population, play an important role in the process of maturation of the claustrum. This is confirmed by the occurrence of these types of neurons at definite stages of maturation and by the increase in their number.
    Nogo (RTN4) belongs to the reticulon (RTN) family of integral membrane proteins. RTN4A (Nogo-A), RTN4B (Nogo-B) and RTN4C (Nogo-C) are isoforms of RTN4. In the gastrocnemius muscle of transgenic mice bearing an SOD1 mutation ("ALS... more
    Nogo (RTN4) belongs to the reticulon (RTN) family of integral membrane proteins. RTN4A (Nogo-A), RTN4B (Nogo-B) and RTN4C (Nogo-C) are isoforms of RTN4. In the gastrocnemius muscle of transgenic mice bearing an SOD1 mutation ("ALS model"), increased Nogo-A mRNA and protein was reported, and similar changes were reported in muscle biopsies of patients with amyotrophic lateral sclerosis (ALS) but not with peripheral neuropathy or primary muscle diseases, leading to the proposal that Nogo-A in skeletal muscle is a new specific molecular marker of ALS. Here we report, based on studies of muscle biopsies from patients with ALS, peripheral neuropathies, polymyositis, dermatomyositis and morphologically nonspecific myopathies that, in addition of strong Nogo-A immunoreactivity within apparently-denervated small angular fibers in ALS and peripheral neuropathies, Nogo-A was strongly immunoreactive within desmin-positive regenerating muscle fibers in various myopathies, and its expression on immunoblots was increased in all those neuromuscular diseases. In conclusion, we have found that the presence of Nogo-A in diseased human muscle biopsies is not limited to ALS.
    Intracerebral haemorrhage is a strong stimulus for both microglial and astroglial activations. There are some important pathophysiological features during haemorrhage that do not occur in ischaemic or traumatic brain injuries, and may... more
    Intracerebral haemorrhage is a strong stimulus for both microglial and astroglial activations. There are some important pathophysiological features during haemorrhage that do not occur in ischaemic or traumatic brain injuries, and may influence the dynamics and intensity of glial activation. Studies on the evolution of glial reaction may have practical importance to the introduction of new therapeutic methods for influencing the inflammatory reaction during haemorrhage. Microglial and astroglial responses to experimental intracerebral haematoma were studied in 50 adult rats for 5 minutes after injection of 100 microl autologous arterial blood into the striatum. The survival period varied from 1 to 21 days. Microglial-macrophage lineage cells were immunocytochemically stained with antibodies OX42, OX6 and ED1. The astrocytic population was studied by means of anti-GFAP staining. Changes in cellular morphology and intensity of staining were time-dependent reactions in both microglial and astroglial cells. Strong activation of microglial-macrophage lineage cells revealed with OX6-and OX42-immunoreactivity started during the first postoperative day. The complete pattern of activation for ED1-immunoreactivity was observed from the third postoperative day. At this stage, numerous phagocytic macrophages started to appear in the perihaematoma region. Morphological changes were most intensive during the second postoperative week. The astroglial (anti-GFAP) reaction was observed after the third postoperative day and proceeded less dynamically. The glial reaction gradually stopped but not completely during the period of observation. The early occurrence of glial activation, pattern of morphological changes and characteristic sequence of antigens expression indicate a very intense type of glial reaction. Evolution of glial response to haemorrhage reveals characteristic features. In our opinion, the initial phase of glial activation, comprising 72 hours after the occurrence of haemorrhage, is potentially the most promising period for influencing the extent of glial reaction with therapeutic agents.
    Sunflower trypsin inhibitor (SFTI-1) is recognized as an attractive scaffold to designed potent inhibitors of various proteases. We have recently found that its analogues inhibit non-covalently both human and yeast 20S proteasomes. Here,... more
    Sunflower trypsin inhibitor (SFTI-1) is recognized as an attractive scaffold to designed potent inhibitors of various proteases. We have recently found that its analogues inhibit non-covalently both human and yeast 20S proteasomes. Here, a set of novel and more potent in vitro inhibitors is presented. The inhibitory potency of the peptides was assessed with human 20S proteasome in the presence or absence of sodium dodecyl sulfate and with human 26 proteasome. Their antiproliferative action against tumor (human melanoma cells A375) and normal cells (46 BR.1N human fibroblasts and HaCaT keratinocytes) was determined. The selected fluoresceine-labeled inhibitors were able to internalize into A375 cells and were sometimes present as foci in the cells. This article is protected by copyright. All rights reserved.
    Myostatin, also called growth and differentiation factor-8, is a member of the transforming growth factor-b superfamily [1,2]. Myostatin is a secreted protein considered a negative regulator of muscle growth during development and of... more
    Myostatin, also called growth and differentiation factor-8, is a member of the transforming growth factor-b superfamily [1,2]. Myostatin is a secreted protein considered a negative regulator of muscle growth during development and of muscle mass during adulthood [1]. In mouse models, knocking out the myostatin gene, overexpressing proteins neutralizing myostatin, or natural mutations of the myostatin gene cause increased muscle mass [1]. In cattle, naturally occurring myostatin gene mutations leading to inactive protein cause ‘double-muscle cattle’ [2]. Recently reported was a child in whom a homozygous myostatin gene mutation that results in reduced production of myostatin protein, was associated with increased muscle bulk and strength [3]. Conversely, mature myostatin protein has been reported increased in muscle tissue of patients with HIV-associated muscle wasting [4], and increased myostatin-precursor protein (MstnPP) mRNA reported in muscle wasting associated with osteoarthritis [5]. Within muscle fibres, myostatin is synthesized as a MstnPP [6,7]. MstnPP and its mRNA, and mature myostatin, are predominantly expressed in skeletal muscle tissue (reviewed in [1]). MstnPP, a 375-amino-acid protein translated from a 3.1 kb mRNA [4], consists of three structural domains: a signal sequence; an N-terminal 28 kDa propeptide, also referred to as latency associated peptide [7]; and a C-terminal 12 kDa mature myostatin peptide [6,7]. Intracellular processing of myostatin from MstnPP has been proposed to occur through furin [6,8]. We recently showed in biopsied sporadic inclusion-body myositis (s-IBM) muscle fibres that both MstnPP and myostatin dimer were significantly increased, and MstnPP was physically associated with amyloid-b precursor protein (AbPP) [9]. Moreover, by lightand electron-microscopic immunocytochemistry, MstnPP/myostatin colocalized with amyloid-b (Ab)/AbPP [9]. s-IBM is severely progressive, the most common muscle disease of older persons, and there is no successful treatment [10]. Histological hallmarks of s-IBM include: (1) vacuolar degeneration and atrophy of muscle fibres, accompanied by intramuscle-fibre accumulations of ubiquitinated protein aggregates, including Ab/AbPP; (2) muscle-fibre atrophy; and (3) mononuclear lymphocytic inflammation [10–12]. Recently demonstrated in s-IBM muscle fibres were inhibition of 26S proteasome activity and presence of aggresomes [13]. Accumulation of AbPP/Ab appears to be an early upstream step in the s-IBM pathogenesis, because: (i) abnormal accumulation of AbPP epitopes appears to precede other abnormalities in IBM muscle fibres [11]; and (ii) several aspects of the s-IBM phenotype, including Ab accumulation, proteasome inhibition and aggresome formation, were produced in cultured normal human muscle fibres (CHMFs) after long-term overexpression of AbPP in them [13–15]. The latter provides a useful IBM human-muscle tissue-culture model. The aim of the present study was to utilize this model to investigate possible mechanisms responsible for increased MstnPP and myostatin within the biopsied s-IBM muscle fibres. We cultured human muscle fibres from satellite cells obtained from six normal diagnostic muscle biopsies, as described [13–15] and referenced therein. Into well-differentiated 3-week-old cultured muscle fibres we transferred a 3 kb human AbPP-cDNA encoding 751-AbPP using a replication-deficient adenovirus vector at 0.3 ¥ 10 pfu/ml culture medium, as detailed previously [14,15]. In addition, we treated some of the cultures with 1 mm epoxomicin (Biomol Research Laboratories, Plymouth Meeting, PA, USA) [13], an irreversible proteasome inhibitor [16]. Four days after AbPP gene transfer and 24 h after epoxomicin treatment, control and AbPP-overexpressing CHMFs (AbPP+ CHMFs) were processed for lightand electron-microscopic immunocytochemistry, immunoblotting, combined immunoprecipitation/immunoblotting, and reverse transcriptase polymerase chain reaction (RT-PCR), as described [13–15,17]. For all the myostatin studies, we used an anti-myostatin rabbit polyclonal antibody (Chemicon,
    In the present work it was investigated if a spontaneous alteration of the native melanotic transplantable melanoma form into amelanotic form, connected with the tumor progression, is accompanied by changes of CD44 surface glycoprotein... more
    In the present work it was investigated if a spontaneous alteration of the native melanotic transplantable melanoma form into amelanotic form, connected with the tumor progression, is accompanied by changes of CD44 surface glycoprotein expression. We also tried to find out if there exists any correlation between changes in CD44 expression and IL-6, TNF-alpha, and IL-10 secretion. Cells of two hamster transplantable melanoma lines: melanotic and amelanotic were used. The levels of TNF-alpha, IL-6, IL-10 in supernatants were determined by the ELISA test. For the detection of CD44 expression by flow cytometry, isolated melanoma cells were stained with the rat anti-mouse CD44 monoclonal antibody. The stained cells were also examined using a fluorescence microscope and a confocal microscopy system. The obtained results indicate that a spontaneous alteration of the native melanotic form into amelanotic form and the associated tumor progression was accompanied by a decrease in CD44 glycoprotein expression on the cell surface and a decrease in IL-6, TNF-alpha and especially IL-10 secretion by amelanotic melanoma cells. Our observations suggest a relationship between CD44 expression and locally secreted cytokines in the course of transplantable melanoma progression.
    The aim of the present study is to follow topographical and morphological changes in the development of the amygdaloid basolateral complex (BLC) in the rabbit. The material consists of 35 brains of New Zealand rabbits of both sexes,... more
    The aim of the present study is to follow topographical and morphological changes in the development of the amygdaloid basolateral complex (BLC) in the rabbit. The material consists of 35 brains of New Zealand rabbits of both sexes, divided into 7 age groups (P2-P90). In cresyl violet preparations BLC is already well visible on P2 and is composed of the lateral (divided into dorsolateral and ventromedial divisions), basolateral and homogenous basomedial nuclei. On about the 7th postnatal day it is possible to divide the basomedial nucleus (BM) into dorsal (Bmd) and ventral (BMv) divisions. The topography and subdivisions set on P7 are maintained in further periods of life. The morphology of neurons (shape, dendrites, staining) changes significantly until P21 in all BLC nuclei. Our results indicate that BLC achieves morphological maturity relatively late, which is probably connected with a long creation of emotional memory and regulation of emotional behaviour.
    The morphometric analysis of changes occurring in the rat and rabbit ventroposterolateral (VPL) nucleus of the thalamus during the postnatal development was performed using unbiased stereological methods. The materials used in the study... more
    The morphometric analysis of changes occurring in the rat and rabbit ventroposterolateral (VPL) nucleus of the thalamus during the postnatal development was performed using unbiased stereological methods. The materials used in the study included 30 Wistar rats and 32 New Zealand rabbits aged from P0 to P180 (P-postnatal day), which were divided into six and eight age groups, respectively. The following stereological parameters of VPL nucleus on the cresyl violet stained sections were determined: volume of the nucleus, numerical density and total number of neurons. The total number of neurons indicated that the development of VPL nucleus in both species ended within the third week of postnatal life. The volume of VPL nucleus increased gradually (by about 2.2 and 5 times in rats and rabbits, respectively) in comparison with the volume of the cerebral hemisphere during the development from P0 to adulthood. The numerical density of VPL neurons decreased rapidly at the beginning of postnatal life and stabilized by the end of the third week. In both species, the gradual increase in the volume of VPL nucleus and the simultaneous decrease in the neuronal density in the first week of postnatal life were mainly caused by changes in the neuropil volume. The total number of cells did not change remarkably during the first postnatal week. However, it decreased significantly during the second week. This decrease was probably due to the naturally occuring cell death. These results show that the most prominent qualitative and quantitative changes in VPL nucleus and its neurons occur during the first two weeks of postnatal life of rats and rabbits. Also, because the thalamocortical relay neurons completely acquire their physiological features, this the most critical period of time for their morphological maturation.
    The aim of the present paper is to describe the morphology and topography of the nuclei of the amygdaloid complex in the rabbit. In the current study we also investigated the intensity of the enzymatic reaction for acetylcholinesterase... more
    The aim of the present paper is to describe the morphology and topography of the nuclei of the amygdaloid complex in the rabbit. In the current study we also investigated the intensity of the enzymatic reaction for acetylcholinesterase (AChE) in the amygdaloid complex and the morphology of its neurones. Material consisted of 5 brains of adult New Zealand rabbit, stained either with cresyl violet or for AChE activity. Although, as in other mammals, the rabbit amygdala consists of two main nuclear groups (corticomedial and basolateral), it reveals a peculiar morphology pattern, forming a transition structure between those observed in the cat and rat. Especially characteristic is the arrangement of the basolateral complex. Within that the ventromedial division of the lateral nucleus seems to be the largest, while its dorsolateral division--the smallest. The arrangement of the corticomedial complex in the rabbit is similar to both the cat and rat. In the rabbit the highest acetylcholinesterase activity is found in the basolateral nucleus and the nucleus of the lateral olfactory tract. The lowest AChE staining is observed in the cortical and medial nuclei, amygdalohippocampal and anterior amygdaloid areas and intercalated masses.
    A comprehensive pathological analysis of inbred strains is essential to define strain-specific spontaneous lesions and to understand whether a specific phenotype results from experimental intervention or reflects a naturally occurring... more
    A comprehensive pathological analysis of inbred strains is essential to define strain-specific spontaneous lesions and to understand whether a specific phenotype results from experimental intervention or reflects a naturally occurring disease. This study aimed to report and describe a novel condition affecting the skeletal muscles of an inbred C57BL/6NCrl mouse colony characterised by large sarcoplasmic vacuoles in the muscle fibres of male mice in the subsarcolemmal spaces and the intermyofibrillary network. There was no muscle weakness, loss of ambulation or cardiac/respiratory involvement. Post-mortem evaluation and histological analysis excluded the presence of pathological accumulations or lesions in other tissues and organs. Changes were seen in fibre size, with many hypotrophic and some slightly hypertrophic fibres. Histological, immunohistochemical and molecular analyses of the vacuolar content revealed dysregulation of the autophagy machinery while ruling out a morphologica...
    The musculocutaneous nerve (MCN) is the terminal branch of the lateral cord of the brachial plexus, and emerges at the inferior border of pectoralis minor muscle. The nerve can interact with the median nerve (MN), adhering to the nerve... more
    The musculocutaneous nerve (MCN) is the terminal branch of the lateral cord of the brachial plexus, and emerges at the inferior border of pectoralis minor muscle. The nerve can interact with the median nerve (MN), adhering to the nerve and sharing fibers with it. During anatomical dissection of twelve cadavers, we have detected a rare variation of the anastomosis between MCN and MN. The knowledge of this anatomical variation could be of great relevance during surgical and clinical practices.
    The incidence of malignant melanoma, the most aggressive skin cancer, is increasing constantly. Despite new targeted therapies, the prognosis for patients with metastatic disease remains poor. Thus, there is a need for new combinational... more
    The incidence of malignant melanoma, the most aggressive skin cancer, is increasing constantly. Despite new targeted therapies, the prognosis for patients with metastatic disease remains poor. Thus, there is a need for new combinational treatments, and antineoplastic agents potentially valuable in this approach are inhibitors of the ubiquitin-proteasome system (UPS). In this work, we analyze the cytotoxicity mechanisms of proteasome inhibitors (MG-132, epoxomicin, and lactacystin) in a specific form of melanoma which does not synthesize melanin-the amelanotic melanoma (Ab cells). We found that the most cytotoxic of the compounds tested was epoxomicin. Caspase-9 activation as well as cytochrome C and AIF release from mitochondria indicated that exposure to epoxomicin induced the mitochondrial pathway of apoptosis. Epoxomicin treatment also resulted in accumulation of Bcl-2 family members-proapoptotic Noxa and antiapoptotic Mcl-1, which were postulated as the targets for bortezomib in...
    Sunflower trypsin inhibitor (SFTI-1) is recognized as an attractive scaffold to designed potent inhibitors of various proteases. We have recently found that its analogues inhibit non-covalently both human and yeast 20S proteasomes. Here,... more
    Sunflower trypsin inhibitor (SFTI-1) is recognized as an attractive scaffold to designed potent inhibitors of various proteases. We have recently found that its analogues inhibit non-covalently both human and yeast 20S proteasomes. Here, a set of novel and more potent in vitro inhibitors is presented. The inhibitory potency of the peptides was assessed with human 20S proteasome in the presence or absence of sodium dodecyl sulfate and with human 26 proteasome. Their antiproliferative action against tumor (human melanoma cells A375) and normal cells (46 BR.1N human fibroblasts and HaCaT keratinocytes) was determined. The selected fluoresceine-labeled inhibitors were able to internalize into A375 cells and were sometimes present as foci in the cells. This article is protected by copyright. All rights reserved.
    Vitamin B 1 2 (cobalamine) is an important factor in the process of nucleic acids synthesis; its deficiency leads not only to anemia, but also to the impairment of the central nervous system. Symptoms caused by this deficiency may occur... more
    Vitamin B 1 2 (cobalamine) is an important factor in the process of nucleic acids synthesis; its deficiency leads not only to anemia, but also to the impairment of the central nervous system. Symptoms caused by this deficiency may occur after a long time of disturbances in the assimilation of vit. B 1 2 . In the present study two cases of posterior fascicles degeneration in patients suffering from Addison-Biermer disease were presented. In both cases the complex of neurological signs was the first symptom of the disease. The diagnosis was very difficult due to the atypical course of the pathological state. It was stated after many diagnostic examinations and the exclusion of other diseases.
    Sarcopenia, the age-related loss of muscle mass and strength, is a multifactorial condition that represents a major healthcare concern for the elderly population. Although its morphologic features have been extensively studied in humans,... more
    Sarcopenia, the age-related loss of muscle mass and strength, is a multifactorial condition that represents a major healthcare concern for the elderly population. Although its morphologic features have been extensively studied in humans, animal models, and domestic and wild animals, only a few reports about spontaneous sarcopenia exist in other long-lived animals. In this work, muscle samples from 60 healthy Podolica-breed old cows (aged 15–23 years) were examined and compared with muscle samples from 10 young cows (3–6 years old). Frozen sections were studied through standard histologic and histoenzymatic procedures, as well as by immunohistochemistry, immunofluorescence, and Western blot analysis. The most prominent age-related myopathic features seen in the studied material included angular fiber atrophy (90% of cases), mitochondrial alterations (ragged red fibers, 70%; COX-negative fibers, 60%), presence of vacuolated fibers (75%), lymphocytic (predominantly CD8+) inflammation (...
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    ABSTRACT
    The broad variety of substances that inhibit the action of the ubiquitin-proteasome system (UPS)-known as proteasome inhibitors-have been used extensively in previous studies, and they are currently frequently proposed as a novel form of... more
    The broad variety of substances that inhibit the action of the ubiquitin-proteasome system (UPS)-known as proteasome inhibitors-have been used extensively in previous studies, and they are currently frequently proposed as a novel form of cancer treatment and as a protective factor in intracerebral hemorrhage treatment. The experimental data on the safest route of proteasome inhibitor administration, their associated side effects, and the possible ways of minimizing these effects have recently become a very important topic. The aim of our present study was to determine the effects of administering of MG-132, lactacystin and epoxomicin, compounds belonging to three different classes of proteasome inhibitors, on the ependymal walls of the lateral ventricle. Observations were made 2 and 8 weeks after the intraventricular administration of the studied substances dissolved in dimethyl sulfoxide (DMSO) into the lateral ventricle of adult Wistar rats. Qualitative and quantitative analysis o...
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