Search results for "physiologic"
showing 10 items of 2593 documents
G2019S Variation in LRRK2: An Ideal Model for the Study of Parkinson's Disease?
2019
Parkinson’s disease (PD) is the second most common neurodegenerative disorder and has plagued humans for more than 200 years. The etiology and detailed pathogenesis of PD is unclear, but is currently believed to be the result of the interaction between genetic and environmental factors. Studies have found that PD patients with the LRRK2:G2019S variation have the typical clinical manifestations of PD, which may be familial or sporadic, and have age-dependent pathogenic characteristics. Therefore, the LRRK2:G2019S variation may be an ideal model to study the interaction of multiple factors such as genetic, environmental and natural aging factors in PD in the future. This article reviewed the …
Alterations in membrane and firing properties of layer 2/3 pyramidal neurons following focal laser lesions in rat visual cortex.
2013
Focal cortical injuries are well known to cause changes in function and excitability of the surviving cortical areas but the cellular correlates of these physiological alterations are not fully understood. In the present study we employed a well established ex vivo-in vitro model of focal laser lesions in the rat visual cortex and we studied membrane and firing properties of the surviving layer 2/3 pyramidal neurons. Patch-clamp recordings, performed in the first week post-injury, revealed an increased input resistance, a depolarized spike threshold as well as alterations in the firing pattern of neurons in the cortex ipsilateral to the lesion. Notably, the reported lesion-induced alteratio…
GABAergic projections from the subplate to Cajal-Retzius cells in the neocortex.
2011
Subplate neurons and Cajal-Retzius cells play an important role in the corticogenesis. Despite morphological evidence, the question whether subplate neurons innervate Cajal-Retzius cells has not been studied yet. We report that electrical stimulation in the subplate resulted in evoked GABAergic inhibitory postsynaptic currents (eIPSCs) in Cajal-Retzius cells. The eIPSC latency showed minor variability and amounted to approximately 4 ms, suggesting the monosynaptic connection. During the first postnatal week: (i) eIPSC amplitude increased, (ii) eIPSC kinetics sped up, (iii) the size of readily releasable pool increased, and (iv) γ-aminobutyric acid release probability decreased. We conclude …
Quantification of the heterogeneity of prognostic cellular biomarkers in ewing sarcoma using automated image and random survival forest analysis
2014
Driven by genomic somatic variation, tumour tissues are typically heterogeneous, yet unbiased quantitative methods are rarely used to analyse heterogeneity at the protein level. Motivated by this problem, we developed automated image segmentation of images of multiple biomarkers in Ewing sarcoma to generate distributions of biomarkers between and within tumour cells. We further integrate high dimensional data with patient clinical outcomes utilising random survival forest (RSF) machine learning. Using material from cohorts of genetically diagnosed Ewing sarcoma with EWSR1 chromosomal translocations, confocal images of tissue microarrays were segmented with level sets and watershed algorithm…
Presence of endothelial progenitor cells, distinct from mature endothelial cells, within human CD146+ blood cells.
2006
SummaryCD146 is an adhesion molecule present on endothelial cells throughout the vascular tree. CD146 is also expressed by circulating endothelial cells (CECs) widely considered to be mature endothelial cells detached from injured vessels. The discovery of circulating endothelial progenitor cells (EPCs) originating from bone marrow prompted us to investigate whether CD146 circulating cells could also contains EPCs. We tested this hypothesis using an approach combining elimination of CECs by an adhesion step, followed by immunomagnetic sorting of remaining CD146+ cells from the non adherent fraction of cord blood mononuclear cells. When cultured under endothelial-promoting conditions, these …
Transplantation of low dose CD34+KDR+ cells promotes vascular and muscular regeneration in ischemic limbs.
2004
Hematopoietic progenitor cell transplantation can contribute to revascularization of ischemic tissues. Yet, the optimal cell population to be transplanted has yet to be determined. We have compared the therapeutic potential of two subsets of human cord blood CD34+ progenitors, either expressing the VEGF-A receptor 2 (KDR) or not. In serum-free starvation culture, CD34+KDR+ cells reportedly showed greater resistance to apoptosis and ability to release VEGF-A, as compared with CD34+KDR- cells. When injected into the hind muscles in immunodeficient SCIDbg mice subjected to unilateral ischemia, a low number (10(3)) of CD34+KDR+ cells improved limb salvage and hemodynamic recovery better than a …
Sprouting and intussusceptive angiogenesis in postpneumonectomy lung growth: mechanisms of alveolar neovascularization
2013
In most rodents and some other mammals, the removal of one lung results in compensatory growth associated with dramatic angiogenesis and complete restoration of lung capacity. One pivotal mechanism in neoalveolarization is neovascularization, because without angiogenesis new alveoli can not be formed. The aim of this study is to image and analyze three-dimensionally the different patterns of neovascularization seen following pneumonectomy in mice on a sub-micron-scale. C57/BL6 mice underwent a left-sided pneumonectomy. Lungs were harvested at various timepoints after pneumonectomy. Volume analysis by microCT revealed a striking increase of 143 percent in the cardiac lobe 14 days after pneum…
Endothelial nitric oxide synthase upregulation in the guinea pig organ of Corti after acute noise trauma.
2004
Endothelial nitric oxide synthase (eNOS) upregulation was identified 60 h after acute noise trauma in morphologically intact cells of the reticular lamina in the organ of Corti of the guinea pig in the second turn of the cochlea. Using gold-coupled anti-eNOS antibodies and electron microscopy, it was shown that eNOS expression was upregulated in all cell areas and cell types except inner hair cells. Furthermore, eNOS was found in the organelle-free cytoplasm and in mitochondria of various cell types. The density of eNOS in mitochondria was considerably higher compared with the surrounding cytoplasm. Since eNOS activity is regulated by calcium, the eNOS detection was combined with calcium pr…
Cell viability, osteoblast differentiation, and gene expression are altered in human osteoblasts from hypertrophic fracture non-unions
2007
Recent studies have provided evidence that the number and proliferation capacity of bone marrow-derived mesenchymal stem cells, as well as the number of osteoprogenitor cells are reduced in patients with fracture non-unions. For fracture non-unions that do not heal after appropriate surgical intervention, the question arises as to what extent systemic cellular dysfunctions should be considered as being pathogenetic factors. For this purpose, we have examined the hypothesis that the cell function of osteoblasts isolated from patients with fracture non-unions may differ from those of normal control individuals in an identical and controlled in vitro situation. We analyzed the osteoblast cell …
Inflammation-Induced Intussusceptive Angiogenesis in Murine Colitis
2010
Intussusceptive angiogenesis is a morphogenetic process that forms new blood vessels by the division of a single blood vessel into two lumens. Here, we show that this process of intraluminal division participates in the inflammation-induced neovascularization associated with chemically induced murine colitis. In studies of both acute (4-7 days) and chronic (28-31 days) colitis, intravital microscopy of intravascular tracers demonstrated a twofold reduction in blood flow velocity. In the acute colitis model, the decreased velocity was associated with marked dilatation of the mucosal plexus. In contrast, chronic inflammation was associated with normal caliber vessels and duplication (and trip…