Publications by authors named "Chojnacki A"

Guelder rose ( L.) is known for its health benefits. contains phenolic compounds (flavonoids and phenolic acids), a group of plant metabolites with wide biological activities.

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Mitochondrial dysfunction as defined by transcriptomic and proteomic analysis of biopsies or ultra-structure in transmission electron microscopy occurs in inflammatory bowel disease (IBD); however, mitochondrial dynamics in IBD have received minimal attention, with most investigations relying on cell-based in vitro models. We build on these studies by adapting the epithelial cell immunofluorescence workflow to imaging mitochondrial networks in normal and inflamed colonic tissue (i.e.

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Intravital imaging of leukocyte-endothelial interactions offers valuable insights into immune-mediated disease in live animals. The study of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) and other respiratory pathologies in vivo is difficult due to the limited accessibility and inherent motion artifacts of the lungs. Nonetheless, various approaches have been developed to overcome these challenges.

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During respiration, humans breathe in more than 10,000 liters of non-sterile air daily, allowing some pathogens access to alveoli. Interestingly, alveoli outnumber alveolar macrophages (AMs), which favors alveoli devoid of AMs. If AMs, like most tissue macrophages, are sessile, then this numerical advantage would be exploited by pathogens unless neutrophils from the blood stream intervened.

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A hallmark feature of inflammation is the orchestrated recruitment of neutrophils from the bloodstream into inflamed tissue. Although selectins and integrins mediate recruitment in many tissues, they have a minimal role in the lungs and liver. Exploiting an unbiased in vivo functional screen, we identified a lung and liver homing peptide that functionally abrogates neutrophil recruitment to these organs.

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Eosinophils are core components of the immune system, yet tools are lacking to directly observe eosinophils in action in vivo. To better understand the role of tissue resident eosinophils, we used eosinophil-specific CRE (eoCRE) mice to create GFP and tdTomato reporters. We then employed intravital microscopy to examine the dynamic behaviour of eosinophils in the healthy GI tract, mesentery, liver, lymph node, skin and lung.

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Hair follicle regeneration is dependent on reciprocal signaling between epithelial cells and underlying mesenchymal cells within the dermal papilla. Hair follicle dermal stem cells reside within the hair follicle mesenchyme, self-renew in vivo, and function to repopulate the dermal papilla and regenerate the connective tissue sheath with each hair cycle. The identity and temporal pattern of signals that regulate hair follicle dermal stem cell function are not known.

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The propagation of neural precursors in culture is an essential tool for the study of the signaling matrix that regulates their proliferation, self-renewal, and generation of terminally differentiated progeny. Neural precursors can be expanded in vitro using both adherent and non-adherent culture protocols. The culture of fetal human neural precursors in the absence of serum as free-floating clusters of cells termed neurospheres is described here.

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Twenty years have past since the existence of neural stem cells (NSCs) within the walls of the adult lateral ventricles was discovered. During this period of time, great strides have been made in every facet of our understanding of this adult periventricular NSC population. In this review, some of the fields' major advancements regarding the nature and function of adult periventricular NSCs are examined.

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Spinal cord injury (SCI) results in substantial oligodendrocyte death and subsequent demyelination leading to white-matter defects. Cell replacement strategies to promote remyelination are under intense investigation; however, the optimal cell for transplantation remains to be determined. We previously isolated a platelet-derived growth factor (PDGF)-responsive neural precursor (PRP) from the ventral forebrain of fetal mice that primarily generates oligodendrocytes, but also astrocytes and neurons.

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Jackson et al. (2006) have reported that adult glial fibrillary acid protein (GFAP)-expressing neural stem cells (NSCs) also express platelet-derived growth factor (PDGF) receptor-α (PDGFRα), and that their stimulation by PDGF induced the formation of a glioma-like mass. Here, we reexamined the relationship between PDGFRα and GFAP expression within the three-dimensional organization of the adult periventricular area.

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The formation of oligodendrocytes (oligodendrogenesis) and myelin is regulated by several neurotrophic factors. Strategies to increase the level of these trophic molecules may facilitate repair in demyelinating conditions, such as multiple sclerosis (MS). Because leukocytes are a source of neurotrophic factors, and as glatiramer acetate (GA) generates T helper 2 (Th2) lymphocytes that are not known to be harmful, we tested the hypothesis that GA regulates oligodendrogenesis and myelin formation.

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Primary glial tumors of the central nervous system, most commonly glioblastoma multiforme (GBM), are aggressive lesions with a dismal prognosis. Despite identification and isolation of human brain tumor stem cells (BTSCs), characteristics that distinguish BTSCs from neural stem cells remain to be elucidated. We cultured cells isolated from gliomas, using the neurosphere culture system, to understand their growth requirements.

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A population of neural stem cells (NSCs) resides adjacent to the lateral ventricles in the adult mammalian brain. Despite knowledge of their existence since the early 1990s, their identity remains controversial, with evidence suggesting that they may be ependymal cells, glial fibrillary acidic protein (GFAP)-expressing subventricular zone (SVZ) cells or several distinct NSC populations. This issue has major implications for the therapeutic use of NSCs as well as for the study and treatment of brain cancers.

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Objective: Platelet-derived growth factor (PDGF)-responsive neural precursors (PRPs; also known as oligodendrocyte progenitor cells) are one of the best characterized precursor cell populations of the rodent central nervous system. Yet little is known about the biology of human PRPs because of an apparent inability to culture and expand them in large numbers. This study was designed to establish an approach that allows direct comparisons between the biology of fetal and adult human PRPs, as a means to address potential differences in intrinsic myelin-production capabilities.

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The isolation and expansion of precursor cells in a serum-free culture system allows for the systematic characterization of their properties and the intrinsic and extrinsic signals that regulate their function. The discovery of neural stem cells in the adult mouse brain was made possible by the creation of a novel culture system subsequently termed the neurosphere assay. Therein, the dissociated adult mouse periventricular area was plated in the presence of epidermal growth factor, but in the absence of adhesive substrates, which resulted in the generation of spheres of proliferating cells that detached from the plate bottom and remained suspended in the media.

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Myelination, the process in which oligodendrocytes coat CNS axons with a myelin sheath, represents an important but poorly understood form of neural plasticity that may be sexually dimorphic in the adult CNS. Remission of multiple sclerosis during pregnancy led us to hypothesize that remyelination is enhanced in the maternal brain. Here we report an increase in the generation of myelin-forming oligodendrocytes and in the number of myelinated axons in the maternal murine CNS.

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The concentrations of 33 elements: Ca, Mg, Na, U, Cu, Zn, P, Fe, Mn, Cr, Se, B, Co, Mo, Si, V, Ni, Be, Hg, Cd, Al, Pb, As, Ba, Au, Pt, Ag, Sr, Sn, Ti, W, Sb and Zr in hair were determined by inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES). Hair samples (n=83) were collected between 1996 and 2003 from inhabitants of city of Wrocław, located in Lower Silesia, south-west Poland (urbanized and industrialized region). Inter-element interactions were studied by evaluation of correlation coefficients between two elements, as well as by multiple regression analysis.

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The process of biosorption of heavy metal ions (Cr3+, Cd2+, Cu2+) by blue-green algae Spirulina sp. is discussed in this paper. Spirulina sp.

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The aim of this work was to estimate, on the basis of soil extraction procedures, whether a given soil is suitable for cultivation of plants used as food or feed. The paper discusses the transfer of metal ions (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn) from contaminated soils to plants in terms of transfer factors (TF). The knowledge of transfer factors for a given element should enable prediction, before plants are sowed, whether a given soil is suitable for the cultivation of plants for consumption purposes.

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Oligodendrocyte progenitor cells express platelet-derived growth factor (PDGF) receptor-alpha and, when expanded in PDGF only, have been shown to generate oligodendrocytes and astrocytes but never neurons. Recent evidence suggests that oligodendrocytes are generated by a common progenitor that also generates neurons but not astrocytes. We used the neurosphere culture system to isolate embryonic ventral forebrain, PDGF-responsive precursors (PRPs).

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Living in a medium that can limit visual information but readily exposes the olfactory organ to hormonal compounds released by conspecifics, fish throughout their long evolutionary history have had both clear cause and ample opportunity to evolve olfactory responsiveness to these potentially important chemical cues (hormonal pheromones). Indeed, water-borne steroids, prostaglandins, and their metabolites are detected with great sensitivity and specificity by the olfactory organs of diverse fishes, and exert important effects on reproductive behavior and physiology in major taxa including carps (goldfish), catfishes, salmon, and gobies. Best understood are goldfish, where periovulatory females sequentially release a preovulatory steroid pheromone and a postovulatory prostaglandin pheromone that dramatically affect male behavior, physiology, and reproductive fitness.

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Glycoprotein130 (gp130) and Notch signaling are thought to participate in neural stem cell (NSC) self-renewal. We asked whether gp130 regulates Notch activity in forebrain epidermal growth factor (EGF)-responsive NSCs. Disruption of Notch1 using antisense or a gamma-secretase inhibitor demonstrated a requirement for Notch1 in the maintenance and proliferation of NSCs.

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