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The article discusses research being done on the relationship between stem cell survival and dopamine neurons and the effects of signaling pathways on the regeneration of brain diseases and in other tissues. The researchers discovered the interaction between insulin and Notch receptors to control the signaling cascade which is fundamental to cell growth. According to them, stem cell survival and dopamine neurons have regenerative effects in brain diseases.

Progressive multifocal leukoencephalopathy is caused by JC virus, an opportunistic infection of the central nervous system. Antiretroviral treatment for progressive multifocal leukoencephalopathy in human immunodeficiency virus-infected patients is beneficial, but few data exist for patients who are not infected with human immunodeficiency virus. Idiopathic CD4+ T lymphocytopenia excludes human immunodeficiency virus infection. We describe a patient with progressive multifocal leukoencephalopathy with underlying idiopathic CD4+ T lymphocytopenia in whom functional recovery occurred without antiviral therapy. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate CatWalk's capability for assessing the functional outcome after photothrombotic stroke affecting the motor cortex of mice. Mice were tested up to 21 days after photothrombosis or sham surgery using CatWalk, and a composite score assessing functional deficits (neuroscore). The neuroscore demonstrated deficits of the contralateral forelimb for more than two weeks after stroke. There were no asymmetric or coordinative dysfunctions of limbs detected by CatWalk. However, CatWalk data revealed impairment of locomotion speed and its depending parameters for one-week after stroke in strong correlation to the neuroscore. Data suggest that the composite neuroscore allows to more sensitively and precisely specify and quantify photothrombosis-induced hemisyndromes than CatWalk., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Low intensity transcranial electrical stimulation (TES) in humans, encompassing transcranial direct current (tDCS), transcutaneous spinal Direct Current Stimulation (tsDCS), transcranial alternating current (tACS), and transcranial random noise (tRNS) stimulation or their combinations, appears to be safe. No serious adverse events (SAEs) have been reported so far in over 18,000 sessions administered to healthy subjects, neurological and psychiatric patients, as summarized here. Moderate adverse events (AEs), as defined by the necessity to intervene, are rare, and include skin burns with tDCS due to suboptimal electrode-skin contact. Very rarely mania or hypomania was induced in patients with depression (11 documented cases), yet a causal relationship is difficult to prove because of the low incidence rate and limited numbers of subjects in controlled trials. Mild AEs (MAEs) include headache and fatigue following stimulation as well as prickling and burning sensations occurring during tDCS at peak-to-baseline intensities of 1-2mA and during tACS at higher peak-to-peak intensities above 2mA. The prevalence of published AEs is different in studies specifically assessing AEs vs. those not assessing them, being higher in the former. AEs are frequently reported by individuals receiving placebo stimulation. The profile of AEs in terms of frequency, magnitude and type is comparable in healthy and clinical populations, and this is also the case for more vulnerable populations, such as children, elderly persons, or pregnant women. Combined interventions (e.g., co-application of drugs, electrophysiological measurements, neuroimaging) were not associated with further safety issues. Safety is established for low-intensity 'conventional' TES defined as <4mA, up to 60min duration per day. Animal studies and modeling evidence indicate that brain injury could occur at predicted current densities in the brain of 6.3-13A/m 2 that are over an order of magnitude above those produced by tDCS in humans. Using AC stimulation fewer AEs were reported compared to DC. In specific paradigms with amplitudes of up to 10mA, frequencies in the kHz range appear to be safe. In this paper we provide structured interviews and recommend their use in future controlled studies, in particular when trying to extend the parameters applied. We also discuss recent regulatory issues, reporting practices and ethical issues. These recommendations achieved consensus in a meeting, which took place in Göttingen, Germany, on September 6-7, 2016 and were refined thereafter by email correspondence., (Copyright © 2017 International Federation of Clinical Neurophysiology. All rights reserved.)

Background and Purpose: In vivo imaging of inflammatory processes is a valuable tool in stroke research. We here investigated the combination of two imaging modalities in the chronic phase after cerebral ischemia: magnetic resonance imaging (MRI) using intravenously applied ultra small supraparamagnetic iron oxide particles (USPIO), and positron emission tomography (PET) with the tracer [(11)C]PK11195., Methods: Rats were subjected to permanent middle cerebral artery occlusion (pMCAO) by the macrosphere model and monitored by MRI and PET for 28 or 56 days, followed by immunohistochemical endpoint analysis. To our knowledge, this is the first study providing USPIO-MRI data in the chronic phase up to 8 weeks after stroke., Results: Phagocytes with internalized USPIOs induced MRI-T2(∗) signal alterations in the brain. Combined analysis with [(11)C]PK11195-PET allowed quantification of phagocytic activity and other neuroinflammatory processes. From 4 weeks after induction of ischemia, inflammation was dominated by phagocytes. Immunohistochemistry revealed colocalization of Iba1+ microglia with [(11)C]PK11195 and ED1/CD68 with USPIOs. USPIO-related iron was distinguished from alternatively deposited iron by assessing MRI before and after USPIO application. Tissue affected by non-phagocytic inflammation during the first week mostly remained in a viably vital but remodeled state after 4 or 8 weeks, while phagocytic activity was associated with severe injury and necrosis accordingly., Conclusions: We conclude that the combined approach of USPIO-MRI and [(11)C]PK11195-PET allows to observe post-stroke inflammatory processes in the living animal in an intraindividual and longitudinal fashion, predicting long-term tissue fate. The non-invasive imaging methods do not affect the immune system and have been applied to human subjects before. Translation into clinical applications is therefore feasible., (Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.)

Minocycline has been reported to reduce infarct size after focal cerebral ischemia, due to an attenuation of microglia activation and prevention of secondary damage from stroke-induced neuroinflammation. We here investigated the effects of minocycline on endogenous neural stem cells (NSCs) in vitro and in a rat stroke model. Primary cultures of fetal rat NSCs were exposed to minocycline to characterize its effects on cell survival and proliferation. To assess these effects in vivo, permanent cerebral ischemia was induced in adult rats, treated systemically with minocycline or placebo. Imaging 7 days after ischemia comprised (i) Magnetic Resonance Imaging (MRI), assessing the extent of infarcts, (ii) Positron Emission Tomography (PET) with [(11)C]PK11195, characterizing neuroinflammation, and (iii) PET with 3'-deoxy-3'-[(18)F]fluoro-L-thymidine ([(18)F]FLT), detecting proliferating endogenous NSCs. Immunohistochemistry was used to verify ischemic damage and characterize cellular inflammatory and repair processes in more detail. In vitro, specific concentrations of minocycline significantly increased NSC numbers without increasing their proliferation, indicating a positive effect of minocycline on NSC survival. In vivo, endogenous NSC activation in the subventricular zone (SVZ) measured by [(18)F]FLT PET correlated well with infarct volumes. Similar to in vitro findings, minocycline led to a specific increase in endogenous NSC activity in both the SVZ as well as the hippocampus. [(11)C]PK11195 PET detected neuroinflammation in the infarct core as well as in peri-infarct regions, with both its extent and location independent of the infarct size. The data did not reveal an effect of minocycline on stroke-induced neuroinflammation. We show that multimodal PET imaging can be used to characterize and quantify complex cellular processes occurring after stroke, as well as their modulation by therapeutic agents. We found minocycline, previously implied in attenuating microglial activation, to have positive effects on endogenous NSC survival. These findings hold promise for the development of novel treatments in stroke therapy., (Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.)

Background: Previous general reservations against carotid endarterectomy (CEA) early after stroke, which were primarily based on concerns of postoperative intracerebral hemorrhage, are resolved. Moreover, a delay of surgery is proofed to be associated with a risk of recurrent cerebral ischemia. However, the complication rate of CEA seems to increase with less time interval to the onset of symptoms. The main purpose of this study was to assess the safety of very early CEA., Patients and Methods: Patients having a symptomatic high-grade (> 70%) internal carotid artery (ICA) stenosis were referred by neurologists for CEA within different timeframes, so that they were later differentiated depending on whether surgery was performed within 2 days (immediate CEA = iCEA) or 2 weeks (urgent CEA = uCEA) after neurological deficits have occurred primarily. The perioperative complication rate in these groups was than evaluated and compared., Results: From January 2000 until August 2006 130 consecutive patients (median age 68 years, range: 42-90; 66% male, 34%female)presenting with an ipsilateral TIA (n = 80), stroke (n = 50) underwent iCEA (n = 40) or uCEA (n = 90). Demographic and clinical characteristics were equally distributed between treatment groups. Mostly (121/130), CEA was performed under local anaesthesia with selective shunt use which became necessary in 26%. Besides postoperative hemorrhage (n = 4), cardiac complications (n = 2) and temporary cranial nerve lesions (n = 2), new perioperative neurological deficits occurred in total in 8 patients of which 6 were temporary. The other 2 patients developed strokes of which one patient died. Therefore, the combined stroke- and mortality rate was 1.5% (2/130) for the whole study population. With regard to the timing of surgery, a single incident was observed after iCEA (1/40) which also was the only intracerebral hemorrhage., Conclusions: It seems that patients with a symptomatic high-grade ICA stenosis can undergo CEA particularly under local anaesthesia as soon as possible without anticipating an increased complication rate.

Over the past decade imaging technologies employed in clinical neurosciences have significantly advanced. Imaging is not only used for the diagnostic work-up of neurological disorders but also crucial to follow up on therapeutic efforts. Using disease-specific imaging parameters, as read-outs for the efficiency of individual therapies, has facilitated the development of various novel treatments for neurological disease. Here, we review various imaging technologies, such as cranial computed tomography (CT), magnetic resonance imaging (MRI) and spectroscopy (MRS), positron emission tomography (PET) and single-photon emission computed tomography (SPECT), with respect to their current applications in non-invasive disease phenotyping and the measurement of therapeutic outcomes in neurology. In particular, applications in neuro-oncology, Parkinson's disease, Alzheimer's disease, and cerebral ischemia are discussed. Non-invasive imaging provides further insights into the molecular pathophysiology of human diseases and facilitates the design and implementation of improved therapies.

Progressive multifocal leukoencephalopathy is caused by JC virus, an opportunistic infection of the central nervous system. Antiretroviral treatment for progressive multifocal leukoencephalopathy in human immunodeficiency virus-infected patients is beneficial, but few data exist for patients who are not infected with human immunodeficiency virus. Idiopathic CD4+ T lymphocytopenia excludes human immunodeficiency virus infection. We describe a patient with progressive multifocal leukoencephalopathy with underlying idiopathic CD4+ T lymphocytopenia in whom functional recovery occurred without antiviral therapy.