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Przedstawiono analizę poziomu eksportu i importu ryb i przetworów rybnych w wyrażeniu wartościowym (w tys. USD) w podziale na grupę 15 krajów UE (tzw. „starej” UE) oraz na grupę 10 krajów, nowych członków UE. Na podstawie zgromadzonego materiału przedstawiono zmiany w wartości handlu światowego rybami i przetworami rybnymi, określono poziom wartości eksportu, importu i saldo obrotów handlowych krajów „starej” Unii Europejskiej i 10 nowo przyjętych państw. Przyjmując podstawowy wskaźnik udziału danego kraju lub grupy krajów w światowym eksporcie i imporcie, określono udział 15 krajów UE i 10 nowo przyjętych krajów do UE w światowym eksporcie i imporcie ryb i przetworów rybnych.
Focal brain damage following stroke leads to severe functional impairments. The aim of the study was to compare therapeutic effectiveness of intra-arterial infusion of HUCB-MNs at different stages of their neural conversion in vitro. Methods: Focal brain damage of dorsolateral striatum was induced in Wistar rats by stereotactic injection of previously established low dose of ouabain (1 μl, 5 mmol). Three days later 107 HUCB-MNs cells were infused (during 3 min) into carotid artery. Thirty days following surgery groups of 7ñ8 rats were housed in large enriched environment cages with various toys. Rats were behaviorally tested for 30 days after lesion. Results: Freshly isolated cells were much more effective in enhancing recovery from motor defi cits measured in walking beam task. Rats treated with HUCB-MNs cells presented also tendency to reduce turning bias and apomorphine induced rotations affected by unilateral lesion. This therapy enhances also recovery from impairments visible in object recognition task. However, rats treated with neurally directed HUCB-MNs also showed a signifi cant improvement in this task. The observed effects were much more prominent in T-maze habit learning task where cell treatment attenuated substantially lesion-induced learning defi cits. What interesting, the mechanism underlying this improvement seems to be different from this observed spontaneously in non-injured animals. Conclusions: Freshly isolated and neurally directed HUCB-MNs differently enhance recovery from distinct functional defi cits induced by focal brain damage. Non-cultured HUCB-MNs seems to be more effective in reducing motor defi cits. Neurally directed HUCB-MNs may be more potent in restoration of impaired habit learning processes. Supported by MSHE grant no 2PO5A05430
The aim of the study was to compare therapeutic effectiveness of intra-arterial infusion of human umbilical cord-blood derived mononuclear (HUCB-MNs) cells at different stages of their neural conversion in vitro. Freshly isolated HUCB-MNs (D-0) neuraly directed progenitors (D-3) obtained during 3 days culture of HUCB-MNs and neural stem cells (NSC) line derived from HUCB-MNs were assessed. Focal brain damage of dorsolateral striatum was induced in Wistar rats by stereotactic injection of previously established low dose of ouabain (1 μl or 1,5 μl 5 mmol). Three days later 107 HUCB cells were infused into carotid artery. Following surgery rats were housed in large enriched environment cages, in groups of 7–8 animals per cage, for 30 days. Behavioral assessing consisted of: tests for sensorimotor defi cits (walking beam task, rotarod), habit learning task, exploratory behavior (open fi eld test) and apomorphine induced rotations. Functional effects of different subsets of HUCB cells were diverse in various behavioral tests and hard to conclude which stage of neural conversion of cord blood cells is the most effective in functional recovery. Additional analysis was applied: scores concerning positive effects of cells treatment visible in all parameters were calculated. The sum of scores revealed that the most effective in functional restoration and reduction of lesion volume were freshly isolated D-0 HUCB cells. Supported by Medical Research Centre statutory fund.
Cerebral ischemia causes severe functional deficits due to the death of neuronal and glial cells in the cortex and sub-cortical regions. Stem cell-based therapy could be used to restore lost cells and thus may enhance functional recovery. The aim of the study was to compare therapeutic effectiveness of intra-arterial infusion of human umbilical cord-blood derived mononuclear cells (HUCB-MNC) at different stages of their neural conversion in vitro. Materials and methods. Freshly isolated HUCB-MNC (D-0) neurally directed progenitors (D-3) obtained during 3 days culture of HUCB-MNC and neural-like stem cells (HUCB-NSC) line derived from human cord blood cells were assessed. Focal brain damage was induced in Wistar rats by stereotactic injection of previously established low dose of ouabain into dorsolateral striatum Three days later 107 HUCB cells were infused into internal carotid artery. Following surgery rats were housed in large enriched environment cages, in groups of 7-8 animals per cage, for 30 days observation period. Behavioral assessment consisted of tests for sensorimotor deficits (walking beam task, rotarod, vibrissae elicited forelimb placing), cognitive impairments (habit learning task and object recognition test), exploratory behavior (open field test) and apomorphine induced rotations. At the end of 30 days observation the lesion volume was measured and the presence of donor cells visualized by the expression of mRNA of human reference gene β-2-microglobulin. Results. Functional effects of different subsets of HUCB-MNC treatment shared substantial diversity in various behavioral tests. In walking beam test the most effective in recovery the impaired sensomotor functions in focal brain injured rats were freshly isolated HUCB-MNC (D-0). Also, in rotarod task and in apomorphine induced rotations the tendency to improve scores was observed 30 days following HUCB-MNC (D-0) treatment. In parameters describing open field exploratory behavior the positive effects of HUCB-MNC (D-0) as well as HUCB-NSC cells treatment were observed. However, in cognitive tasks none of tested cell subsets reduced the functional deficits induced by ouabain injection. Thirty days after HUCB cell transplantation we did not observed any mRNA expression of human reference gene in the rat brain samples. Conclusions. Our observation reveals that freshly isolated D-0 HUCB-MNC are the most effective in functional recovery of injured rats. These cells are also the most potent in reducing the ouabain-induced brain lesion volume. The best functional outcome observed after transplantation of HUCB-MNC (D-0) is probably due to the positive effect of therapeutic molecules secreted by these cells than the persistence of donor per se in the host since we did not detect systemically infused human cells in rat brains. Supported by MSHE grant no. 0394/B/P01/2010/38.
Stem cell transplantation offers an exciting new therapeutic avenue for stroke not only to prevent damage, which has been the focus of conventional therapeutic strategies, but also to actually repair the injured brain. Indeed, exogenous stem cell grafting in animal models of CNS damage improves function by replacing the lost neurons. However, therapeutic mechanism different from the expected contribution of cell replacement have been also postulated. Many studies applying systemic delivery of cells in ischemic stroke disorders have shown significant functional recovery with very few or frequently no cells entering brain. It seems that transplanted cells could propel local micro-environmental signals to sustain active endeavors for damaged neurons substitution. The question arises if systemic infusion of cells enhances endogenous neurogenesis previously activated by focal ischemic brain injury. Materials and methods: Experimental model of focal ischemic brain injury was performed by local application of Na/K ATP-ase pump inhibitor - ouabain (OUA) (1 µl/50nmol) into the striatum of CsA-immunosuppressed adult Wistar rats. Three days later 107 human umbilical cord blood CD34- mononuclear cells (HUCB-MNC) were infused into internal carotic artery. At 30 day thereafter rat brains were removed and the neurogenic regions and tissue around the damaged areas were analyzed immunohistochemically. Results: Analysis of brain tissue in OUA injured rats transplanted with HUCB-MNC revealed augmentation of proliferative cells (Ki-67+) in subventricular zone (SVZ) of ipsilateral hemisphere and at the border of the lesion area as well as higher number of DCX+ cells in SVZ. Moreover, the extensive neuroblast migration and their accumulation in the perinfarct striatum were observed in comparison to non-transplanted rats after OUA injury onset. HUCB-MNC injection into rats with brain infarct showed a significant increase of cells with immature (Nestin+) or more mature (NF-200+) neuronal phenotypes observed in the tissue alongside OUA lesion. The intensive staining of GFAP at the border of injured area in HUCB-MNC transplanted and nontransplanted rats reflected gliosis however, the increased expression of GFAP in brain tissue of the former ones may point to the possible expansion of endogenous progenitors. In conclusions, HUCB-MNC transplanted systemically into OUA focal ischemic brain injured rats activate the endogenous stem cell compartment where the newly arisen cells adopt a neuronal or astrocytic fate. This effect may prove applicable for future clinical therapy. Supported by MSHE grants: 0142/B/P01/2008/35 and 0394/B/ P01/2010/38
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