Therapeutically Targeting Neuroinflammation and Microglia after Acute Ischemic Stroke

Inflammation has a pivotal role in the pathogenesis of ischemic stroke, and recent studies posit that inflammation acts as a double-edged sword, not only detrimentally augmenting secondary injury, but also potentially promoting recovery. An initial event of inflammation in ischemic stroke is the activation of microglia, leading to production of both pro- and anti-inflammatory mediators acting through multiple receptor signaling pathways. In this review, we discuss the role of microglial mediators in acute ischemic stroke and elaborate on preclinical and clinical studies focused on microglia in stroke models. Understanding how microglia can lead to both pro- and anti-inflammatory responses may be essential to implement therapeutic strategies using immunomodulatory interventions in ischemic stroke

Development of an assessment method for freely moving nonhuman primates’ eating behavior using manual and deep learning analysis

Purpose: Although eating is imperative for survival, few comprehensive methods have been developed to assess freely moving nonhuman primates' eating behavior. In the current study, we distinguished eating behavior into appetitive and consummatory phases and developed nine indices to study them using manual and deep learning-based (DeepLabCut) techniques. Method: The indices were utilized to three rhesus macaques by different palatability and hunger levels to validate their utility. To execute the experiment, we designed the eating behavior cage and manufactured the artificial food. The total number of trials was 3, with 1 trial conducted using natural food and 2 trials using artificial food. Result: As a result, the indices of highest utility for hunger effect were approach frequency and consummatory duration. Appetitive composite score and consummatory duration showed the highest utility for palatability effect. To elucidate the effects of hunger and palatability, we developed 2D visualization plots based on manual indices. These 2D visualization methods could intuitively depict the palatability perception and hunger internal state. Furthermore, the developed deep learning-based analysis proved accurate and comparable with manual analysis. When comparing the time required for analysis, deep learning-based analysis was 24-times faster than manual analysis. Moreover, temporal and spatial dynamics were visualized via manual and deep learning-based analysis. Based on temporal dynamics analysis, the patterns were classified into four categories: early decline, steady decline, mid-peak with early incline, and late decline. Heatmap of spatial dynamics and trajectory-related visualization could elucidate a consumption posture and a higher spatial occupancy of food zone in hunger and with palatable food. Discussion: Collectively, this study describes a newly developed and validated multi-phase method for assessing freely moving nonhuman primate eating behavior using manual and deep learning-based analyses. These effective tools will prove valuable in food reward (palatability effect) and homeostasis (hunger effect) research

Evolution of implanted Fe ions in SiO2/Si wafer into uniformly sized catalyst particles for carbon nanotube forest growth

We report the synthesis of carbon nanotube (CNT) forests with a narrow diameter distribution based on Fe ion implantation method. By annealing the Fe-implanted SiO2/Si wafer in an Ar atmosphere at 800 degrees C for 15 min, the Fe particles on the surface of SiO2 layer are successfully formed by the diffusion of Fe atoms from the SiO2 layer. Interestingly, the size distribution of Fe catalyst particles for Fe-implanted SiO2/Si wafers does not change with the prolonged annealing durations of up to 12 h. Using secondary ion mass spectroscopy and transmission electron microscopy (TEM), we confirmed that the implanted Fe atoms diffuse out of the SiO2 layer and form Fe particles on both the SiO2 surface and the interface between SiO2 and Si. The cross-sectional TEM images indicate that the Fe catalyst particles are anchored in the SiO2 layer, which limits the particles' mobility and results in an invariant catalyst size distribution for prolonged annealing durations. Therefore, we anticipate that implantation can be an efficient alternative catalyst preparation method for CNT forest growth which can solve various growth issues that are inherently caused by conventional physical vapor deposition method. (C) 2017 Elsevier Ltd. All rights reserved.112sciescopu

Langerhans cells prevent subbasal nerve damage and upregulate neurotrophic factors in dry eye disease

<div><p>The functional role of Langerhans cells (LCs) in ocular surface inflammation and nerve damage in dry eye (DE) disease has yet to be determined. This study was performed to investigate this relationship through both clinical study on DE patients and in vivo mouse models with induced DE disease. In a cross-sectional case-control study (54 eyes of DE patients; 34 eyes of control patients), average cell density, area, and process length of LCs were measured using confocal microscopy. Data were analyzed to determine whether changes in LCs are correlated with subbasal nerve plexus (SNP) parameters (nerve density, beading, and tortuosity). In DE patients, SNP density marginally decreased and nerve beading and tortuosity were significantly increased compared to the control group. The total number of LCs significantly increased in DE patients, and some LCs with elongated processes were found to be attached to nerve fibers. Interestingly, nerve loss and deformation were correlated with inactivation of LCs. In an <i>in vivo</i> experiment to elucidate the role of LCs in ocular surface inflammation and corneal nerve loss, we used a genetically modified mouse model (CD207-DTR) that reduced the population of CD207 (Langerin) expressing cells by injection of diphtheria toxin. In CD207-depleted mice with DE disease (CD207-dDTR+DE), corneal nerves in the central region were significantly decreased, an effect that was not observed in wild-type (WT)+DE mice. In CD207-dDTR+DE mice, infiltration of CD4+, CD19+, CD45+, and CD11b+ cells into the ocular surface was increased, as confirmed by flow cytometry. Increased IL-17 and IFN-γ mRNA levels, and decreased expression of neurotrophic factors and neurotransmitters, were also found in the CD207-dDTR+DE mice. These data support a functional role for LCs in negatively regulating ocular surface inflammation and exhibiting a neuroprotective function in DE disease.</p></div

Increased inflammatory cell infiltration in LC-depleted mice by DE induction.

<p>(A) Flow cytometry was performed in WT, CD207-dDTR, WT+DE, and CD207-dDTR+DE mice. Cornea samples with limbal tissues were secured and prepared for FACS analysis using anti-CD45-FITC, anti-CD11b-APC, anti-CD4-FITC, and anti-CD19-PE-Cy7 as described in Materials and Methods. At least four mice were included in each group and the experiment was repeated three times. (B) Data were represented as mean ± SD (*: p<0.05, **: p<0.01, ***: p<0.0001 by Student’s t-test).</p

Reduction of corneal nerves in CD207-dDTR+DE mice.

<p>(A-C) After 7 days of DE induction of WT mice and CD207-dDTR mice, immunostaining for βIII tubulin (green) on a corneal flap mount was performed and compared with a non-DE induced control (CONT). (A) Low magnification (× 40) photo images. White arrowheads indicate corneal nerves on limbal area with larger diameter (>20 μm) and yellow arrows indicate mid-corneal nerve leashes. (B) High magnification (× 100 upper row and × 200 lower row) images were taken. (C) Limbal and paracentral corneal nerve leashes were compared using ImageJ software in high magnification images between CONT, WT+DE and CD207-dDTR+DE mice. Yellow arrowheads mark the small nerve fibers on the superficial surface of limbal area. At least five mice were included in each group, and nerve length was measured and is represented as mean ± SD. Dashed white line: limbal margin, Cj: conjunctiva, NS: no statistical significance, ***; p<0.0001, One-way ANOVA with Dunnett’s post-hoc test.</p