Background: Astrocytes are the most abundant cell type of the central nervous system and are fundamentally involved in homeostasis, neuroprotection, and synaptic plasticity. This regulatory function of astrocytes on their neighboring cells in the healthy brain is subject of current research. In the ischemic brain we assume disease specific differences in astrocytic acting.
View Article and Find Full Text PDFGlia are critical players in defining synaptic contacts and maintaining neuronal homeostasis. Both astrocytes as glia of the central nervous system (CNS), as well as satellite glial cells (SGC) as glia of the peripheral nervous system (PNS), intimately interact with microglia, especially under pathological conditions when glia regulate degenerative as well as regenerative processes. The chemotherapeutic agent paclitaxel evokes peripheral neuropathy and cognitive deficits; however, the mechanisms underlying these diverse clinical side effects are unclear.
View Article and Find Full Text PDFThe neural stem cell (NSC) niche is a highly vascularized microenvironment that supplies stem cells with relevant biological and chemical cues. However, the NSCs' proximity to the vasculature also means that the NSCs are subjected to permanent tissue deformation effected by the vessels' heartbeat-induced pulsatile movements. Cultivating NSCs under common culture conditions neglects the-yet unknown-influence of this cyclic mechanical strain on neural stem cells.
View Article and Find Full Text PDFThe glycoprotein osteopontin is highly upregulated in central nervous system (CNS) disorders such as ischemic stroke. Osteopontin regulates cell growth, cell adhesion, homeostasis, migration, and survival of various cell types. Accordingly, osteopontin is considered an essential regulator of regeneration and repair in the ischemic milieu.
View Article and Find Full Text PDFThe development of the cerebral cortex relies on the controlled division of neural stem and progenitor cells. The requirement for precise spatiotemporal control of proliferation and cell fate places a high demand on the cell division machinery, and defective cell division can cause microcephaly and other brain malformations. Cell-extrinsic and -intrinsic factors govern the capacity of cortical progenitors to produce large numbers of neurons and glia within a short developmental time window.
View Article and Find Full Text PDFBackground And Purpose: The translational roadblock has long impeded the implementation of experimental therapeutic approaches for stroke into clinical routine. Considerable interspecies differences, for example, in brain anatomy and function, render comparisons between rodents and humans tricky, especially concerning brain reorganization and recovery of function. We tested whether stroke-evoked changes in neural networks follow similar patterns in mice and patients using a systems-level perspective.
View Article and Find Full Text PDFA 56-year-old woman was initially diagnosed with optic neuritis. However, several "red flags" were present: older age at presentation, no multiple sclerosis suspicious findings on MRI, and negative oligoclonal bands. 68Ga-DOTATATE PET/CT confirmed the differential diagnosis of an optic sheath meningioma.
View Article and Find Full Text PDFThe past decade has brought tremendous progress in diagnostic and therapeutic options for cerebrovascular diseases as exemplified by the advent of thrombectomy in ischemic stroke, benefitting a steeply increasing number of stroke patients and potentially paving the way for a renaissance of neuroprotectants. Progress in basic science has been equally impressive. Based on a deeper understanding of pathomechanisms underlying cerebrovascular diseases, new therapeutic targets have been identified and novel treatment strategies such as pre- and post-conditioning methods were developed.
View Article and Find Full Text PDFFortschr Neurol Psychiatr
April 2021
Background: It is estimated that 240,000 people suffer from multiple sclerosis in Germany. In addition to sensory, motor, vegetative, and neuropsychological functional deficits, dysphagia is a highly relevant and disabling, although not well studied symptom of MS.
Objectives: The purpose of this article is to provide an overview of the scientific background, increase awareness of the symptoms of dysphagia, and to introduce diagnostic tools for its management, overall aiming at alleviating symptoms of dysphagia in persons with MS, and improving their quality of life.
Front Cell Neurosci
November 2020
Microglia-the brain's primary immune cells-exert a tightly regulated cascade of pro- and anti-inflammatory effects upon brain pathology, either promoting regeneration or neurodegeneration. Therefore, harnessing microglia emerges as a potential therapeutic concept in neurological research. Recent studies suggest that-besides being affected by chemokines and cytokines-various cell entities in the brain relevantly respond to the mechanical properties of their microenvironment.
View Article and Find Full Text PDFBackground: Microglia are essential to maintain cell homeostasis in the healthy brain and are activated after brain injury. Upon activation, microglia polarize towards different phenotypes. The course of microglia activation is complex and depends on signals in the surrounding milieu.
View Article and Find Full Text PDFBackground: In cerebral ischemia, microglia have a dichotomous role in keeping the balance between pro- and anti-inflammatory mediators to avoid deleterious chronic inflammation and to leverage repair processes.
Methods: We examined functional and inflammatory markers in primary rat microglia in vitro after oxygen-glucose deprivation (OGD) or glucose deprivation (aglycemia). We then investigated the preconditioning effect of OGD or aglycemia upon a subsequent strong inflammatory stimulus, here lipopolysaccharides (LPS).
Despite its extensive use in clinical studies, the molecular mechanisms underlying the effects of transcranial direct current stimulation (tDCS) remain to be elucidated. We previously described subacute effects of tDCS on immune- and stem cells in the rat brain. To investigate the more immediate effects of tDCS regulating those cellular responses, we treated rats with a single session of either anodal or cathodal tDCS, and analyzed the gene expression by microarray; sham-stimulated rats served as control.
View Article and Find Full Text PDFIn the brain, neural stem cells (NSC) are tightly regulated by external signals and biophysical cues mediated by the local microenvironment or "niche." In particular, the influence of tissue elasticity, known to fundamentally affect the function of various cell types in the body, on NSC remains poorly understood. We, accordingly, aimed to characterize the effects of elastic substrates on critical NSC functions.
View Article and Find Full Text PDFBackground: Microglia-the resident immune cells of the brain-are activated after brain lesions, e.g., cerebral ischemia, and polarize towards a classic "M1" pro-inflammatory or an alternative "M2" anti-inflammatory phenotype following characteristic temporo-spatial patterns, contributing either to secondary tissue damage or to regenerative responses.
View Article and Find Full Text PDFBackground: Osteopontin (OPN), an acidic phosphoglycoprotein, is upregulated in the brain after cerebral ischemia. We previously reported that OPN supports migration, survival, and proliferation of neural stem cells (NSC) in primary cell culture, as well as their differentiation into neurons. We here analyzed the effects of OPN on neuroblasts in vivo in the context of cerebral ischemia.
View Article and Find Full Text PDFOsteopontin (OPN) is constitutively expressed in the brain and upregulated during neuroinflammation, e.g., focal cerebral ischemia.
View Article and Find Full Text PDFMobilizing endogenous neural stem cells (NSCs) in the adult brain is designed to enhance the brain's regenerative capacity after cerebral lesions, e.g., as a result of stroke.
View Article and Find Full Text PDFSleep Breath
December 2012
Purpose: An elevated prevalence of sleep apnoea (SA) in patients with acromegaly has been suggested.
Methods: We performed polysomnographies in 52 patients with acromegaly (25 m, 27 f, age 51 years, range 19-82 years). Patients were defined having SA if they had more than five apnoeas or hypopnoeas per hour (respiratory disturbance index = RDI).
Background And Study Aim: The aim of this study was to develop an algorithm to detect small-bowel metastasis (SBM) of melanoma by sequential laboratory parameters and pan-intestinal endoscopy (PIE) including video capsule endoscopy (VCE).
Patients And Methods: A total of 390 melanoma patients (AJCC stage I/II/III/IV, 140/80/121/49) were screened for signs of intestinal blood loss (fecal occult blood test [FOBT] or overt bleeding) in an open, multicenter, prospective study, and those who were positive underwent PIE. Independent of the presence of intestinal bleeding, all stage IV patients were offered PIE.
Climate models incorporate photosynthesis-climate feedbacks, yet we lack robust tools for large-scale assessments of these processes. Recent work suggests that carbonyl sulfide (COS), a trace gas consumed by plants, could provide a valuable constraint on photosynthesis. Here we analyze airborne observations of COS and carbon dioxide concentrations during the growing season over North America with a three-dimensional atmospheric transport model.
View Article and Find Full Text PDFWe present a statistical representation of the aggregate effects of deep convection on the chemistry and dynamics of the upper troposphere (UT) based on direct aircraft observations of the chemical composition of the UT over the eastern United States and Canada during summer. These measurements provide unique observational constraints on the chemistry occurring downwind of convection and the rate at which air in the UT is recycled. These results provide quantitative measures that can be used to evaluate global climate and chemistry models.
View Article and Find Full Text PDFA differential absorption lidar has been built to measure CO2 concentration in the atmosphere. The transmitter is a pulsed single-frequency Ho:Tm:YLF laser at a 2.05-microm wavelength.
View Article and Find Full Text PDFThe adrenostatic compound aminoglutethimide (AG), a potent inhibitor of the P450 side chain cleavage enzyme, is used in the treatment of ACTH-dependent or adrenal Cushing's syndrome. Recently, AG has been shown to inhibit ACTH receptor (ACTH-R) mRNA expression in ovine adrenocortical cells in a time-dependent fashion. To investigate whether ACTH-R down-regulation will also be induced in tumor cells, we studied the effect of AG on ACTH-R expression in the human NCI-h295 adrenocortical carcinoma cell line, which expresses functional ACTH receptors and produces steroids of the glucocorticoid, mineralocorticoid and androgen pathway.
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