227 research outputs found
Signatures of balancing selection in toll-like receptor (TLRs) genes – novel insights from a free-living rodent
Correction to: Scientific Reports https://doi.org/10.1038/s41598-018-26672-2, published online 30 May 2018 “The work was supported by grant no. DEC-2012/07/B/NZ8/00058 from the Polish National Science Centre to A.K. Field studies were funded by grant MNiI 2P04C09827 „Badania naturalnych źródeł zarażenia mikropasożytów patogennych dla człowieka” to AB. We are thankful to Dr. hab W. Babik who provided access to an Illumina MiSeq platform, and to K. Dudek who prepared the Nextera library. Special thanks to A. Biedrzycka for her valuable comments on the final version of the manuscript. We also would like to thank two anonymous reviewers for their valuable comments that helped to improve the manuscript.”Peer reviewedPublisher PD
Autonomic reactions and peri-interventional alterations in body weight as potential supplementary outcome parameters for thromboembolic stroke in rats
BACKGROUND: Since several neuroprotectives failed to reproduce promising preclinical results under clinical conditions, efforts emerged to implement clinically relevant endpoints in animal stroke studies. Thereby, insufficient attention was given on autonomic reactions due to experimental stroke, although clinical trials reported on high functional and prognostic impact. This study focused on autonomic consequences and body weight changes in a translational relevant stroke model and investigated interrelations to different outcome measurements. METHODS: Forty-eight rats underwent thromboembolic middle cerebral artery occlusion (MCAO) while recording heart rate (HR) and mean arterial pressure (MAP). After assessing early functional impairment (Menzies score), animals were assigned to control procedure or potentially neuroprotective treatment with normobaric (NBO) or hyperbaric oxygen (HBO). Four or 24 hours after ischemia onset, functional impairment was re-assessed and FITC-albumin administered intravenously obtaining leakage-related blood–brain barrier (BBB) impairment. Body weight was documented prior to MCAO and 4 or 24 hours after ischemia onset. RESULTS: During MCAO, HR was found to increase significantly while MAP decreased. The amount of changes in HR was positively correlated with early functional impairment (P = 0.001): Severely affected animals provided an increase of 15.2 compared to 0.8 beats/minute in rats with low impairment (P = 0.048). Regarding body weight, a decrease of 9.4% within 24 hours after MCAO occurred, but treatment-specific alterations showed no significant correlations with respective functional or BBB impairment. CONCLUSIONS: Future studies should routinely include autonomic parameters to allow inter-group comparisons and better understanding of autonomic reactions due to experimental stroke. Prospectively, autonomic consequences might represent a useful outcome parameter enhancing the methodological spectrum of preclinical stroke studies
Pain in patients with multiple sclerosis: a complex assessment including quantitative and qualitative measurements provides for a disease-related biopsychosocial pain model
Classification of Microglial Morphological Phenotypes Using Machine Learning
Microglia are the brain’s immunocompetent macrophages with a unique feature that
allows surveillance of the surrounding microenvironment and subsequent reactions to
tissue damage, infection, or homeostatic perturbations. Thereby, microglia’s striking
morphological plasticity is one of their prominent characteristics and the categorization of
microglial cell function based on morphology is well established. Frequently, automated
classification of microglial morphological phenotypes is performed by using quantitative
parameters. As this process is typically limited to a few and especially manually chosen
criteria, a relevant selection bias may compromise the resulting classifications. In our
study, we describe a novel microglial classification method by morphological evaluation
using a convolutional neuronal network on the basis of manually selected cells in addition
to classical morphological parameters. We focused on four microglial morphologies,
ramified, rod-like, activated and amoeboid microglia within the murine hippocampus
and cortex. The developed method for the classification was confirmed in a mouse
model of ischemic stroke which is already known to result in microglial activation
within affected brain regions. In conclusion, our classification of microglial morphological
phenotypes using machine learning can serve as a time-saving and objective method
for post-mortem characterization of microglial changes in healthy and disease mouse
models, and might also represent a useful tool for human brain autopsy samples
Przewoźna maszyna wyciągowa B-1200/M/AC-2m/s – mobilność bez ograniczeń
W artykule zaprezentowano przewoźną maszynę wyciągową B-1200/M/AC-2m/s, produkcji MWM Elektro Sp. z o. o., umożliwiającą szybkie i swobodne jej przemieszczanie między obsługiwanymi szybami. Przedstawiono opis techniczny maszyny wyciągowej, jak i wymagania przepisów ruchu drogowego, z którymi musieli się zmierzyć konstruktorzy przewoźnej maszyny wyciągowej podczas jej projektowania
Interrelations between blood-brain barrier permeability and matrix metalloproteinases are differently affected by tissue plasminogen activator and hyperoxia in a rat model of embolic stroke
<p>Abstract</p> <p>Background</p> <p>In ischemic stroke, blood-brain barrier (BBB) regulations, typically involving matrix metalloproteinases (MMPs) and inhibitors (TIMPs) as mediators, became interesting since tissue plasminogen activator (tPA)-related BBB breakdown with risk of secondary hemorrhage was considered to involve these mediators too. Despite high clinical relevance, detailed interactions are purely understood. After a pilot study addressing hyperoxia as potential neuroprotective co-treatment to tPA, we analyzed interrelations between BBB permeability (BBB-P), MMPs and TIMPs.</p> <p>Findings</p> <p>Rats underwent embolic middle cerebral artery occlusion (eMCAO) and treatment with normobaric (NBO) or hyperbaric oxygen (HBO), tPA, tPA+HBO, or no treatment. BBB-P was assessed by intravenously applied FITC-albumin at 4 or 24 hours. MMP-2/-9 and TIMP-1/-2 serum levels were determined at 5 or 25 hours. Time point-corrected partial correlations were used to explore interrelations of BBB-P in ischemic regions (extra-/intravasal FITC-albumin ratio) and related serum markers. BBB-P correlated positively with MMP-2 and MMP-9 in controls, whereas hyperoxia led to an inverse association, most pronounced for HBO/MMP-9 (r = -0.606; <it>P </it>< 0.05). As expected, positive coefficients were observed after treatment with tPA. Co-treatment with HBO attenuated and in part reversed this effect, but to a lower degree than HBO alone. Amongst MMPs and TIMPs, significant associations shifted from MMP-9 to -2 when comparing treatment with HBO/tPA and tPA+HBO. TIMPs were significantly interrelated after tPA, tPA+HBO, and interestingly, HBO alone.</p> <p>Conclusions</p> <p>HBO was found to reverse the positively directed interrelation of BBB-P and MMPs after eMCAO, but this effect failed to sustain in the expected amount when HBO and tPA were given simultaneously.</p
A Combined Clinical and Serum Biomarker-Based Approach May Allow Early Differentiation Between Patients With Minor Stroke and Transient Ischemic Attack as Well as Mid-term Prognostication
Background: Early differentiation between transient ischemic attack (TIA) and minor
ischemic stroke (MIS) impacts on the patient’s individual diagnostic work-up and
treatment. Furthermore, estimations regarding persisting impairments after MIS are
essential to guide rehabilitation programs. This study evaluated a combined clinical- and
serum biomarker-based approach for the differentiation between TIA and MIS as well as
the mid-term prognostication of the functional outcome, which is applicable within the
first 24 h after symptom onset.
Methods: Prospectively collected data were used for a retrospective analysis including
the neurological deficit at admission (National Institutes of Health Stroke Scale, NIHSS)
and the following serum biomarkers covering different pathophysiological aspects of
stroke: Coagulation (fibrinogen, antithrombin), inflammation (C reactive protein), neuronal
damage in the cellular [neuron specific enolase], and the extracellular compartment
[matrix metalloproteinase-9, hyaluronic acid]. Further, cerebral magnetic resonance
imaging was performed at baseline and day 7, while functional outcome was evaluated
with the modified Rankin Scale (mRS) after 3, 6, and 12 months.
Results: Based on data from 96 patients (age 64 ± 14 years), 23 TIA patients (NIHSS
0.6 ± 1.1) were compared with 73 MIS patients (NIHSS 2.4 ± 2.0). In a binary logistic
regression analysis, the combination of NIHSS and serum biomarkers differentiated MIS
from TIA with a sensitivity of 91.8% and a specificity of 60.9% [area under the curve
(AUC) 0.84]. In patients with NIHSS 0 at admission, this panel resulted in a still acceptable
sensitivity of 81.3% (specificity 71.4%, AUC 0.69) for the differentiation between MIS (n =
16) and TIA (n = 14). By adding age, remarkable sensitivities of 98.4, 100, and 98.2% for
the prediction of an excellent outcome (mRS 0 or 1) were achieved with respect to time
points investigated within the 1-year follow-up. However, the specificity was moderate
and decreased over time (83.3, 70, 58.3%; AUC 0.96, 0.92, 0.91).
Conclusion: This pilot study provides evidence that the NIHSS combined with selected
serum biomarkers covering pathophysiological aspects of stroke may represent a useful
tool to differentiate between MIS and TIA within 24 h after symptom onset. Further, this
approach may accurately predict the mid-term outcome in minor stroke patients, which
might help to allocate rehabilitative resources
Recent progress in translational research on neurovascular and neurodegenerative disorders
The already established and widely used intravenous application of recombinant tissue plasminogen activator as a re-opening strategy for acute vessel occlusion in ischemic stroke was recently added by mechanical thrombectomy, representing a fundamental progress in evidence-based medicine to improve the patient’s outcome. This has been paralleled by a swift increase in our understanding of pathomechanisms underlying many neurovascular diseases and most prevalent forms of dementia. Taken together, these current advances offer the potential to overcome almost two decades of marginally successful translational research on stroke and dementia, thereby spurring the entire field of translational neuroscience. Moreover, they may also pave the way for the renaissance of classical neuroprotective paradigms.
This review reports and summarizes some of the most interesting and promising recent achievements in neurovascular and dementia research. It highlights sessions from the 9th International Symposium on Neuroprotection and Neurorepair that have been discussed from April 19th to 22nd in Leipzig, Germany. To acknowledge the emerging culture of interdisciplinary collaboration and research, special emphasis is given on translational stories ranging from fundamental research on neurode- and -regeneration to late stage translational or early stage clinical investigations
Regionally Altered Immunosignals of Surfactant Protein-G, Vascular and Non-Vascular Elements of the Neurovascular Unit after Experimental Focal Cerebral Ischemia in Mice, Rats, and Sheep
The surfactant protein-G (SP-G) has recently been discovered in the brain and linked to
fluid balance regulations. Stroke is characterized by impaired vessel integrity, promoting water
influx and edema formation. The neurovascular unit concept (NVU) has been generated to cover not
only ischemic affections of neurons or vessels but also other regionally associated cells. This study
provides the first spatio-temporal characterization of SP-G and NVU elements after experimental
stroke. Immunofluorescence labeling was applied to explore SP-G, vascular and cellular markers
in mice (4, 24, and 72 h of ischemia), rats (24 h of ischemia), and sheep (two weeks of ischemia).
Extravasated albumin indicated vascular damage within ischemic areas. Quantifications revealed
decreasing SP-G signals in the ischemia-affected neocortex and subcortex. Inverse immunosignals
of SP-G and vascular elements existed throughout all models. Despite local associations between
SP-G and the vasculature, a definite co-localization was not seen. Along with a decreased SP-
G-immunoreactivity in ischemic areas, signals originating from neurons, glial elements, and the
extracellular matrix exhibited morphological alterations or changed intensities. Collectively, this
study revealed regional alterations of SP-G, vascular, and non-vascular NVU elements after ischemia,
and may thus stimulate the discussion about the role of SP-G during stroke
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