Targeting Antioxidant Enzyme Expression as a Therapeutic Strategy for Ischemic Stroke

During ischemic stroke, neurons and glia are subjected to damage during the acute and neuroinflammatory phases of injury. Production of reactive oxygen species (ROS) from calcium dysregulation in neural cells and the invasion of activated immune cells are responsible for stroke-induced neurodegeneration. Scientists have failed thus far to identify antioxidant-based drugs that can enhance neural cell survival and improve recovery after stroke. However, several groups have demonstrated success in protecting against stroke by increasing expression of antioxidant enzymes in neural cells. These enzymes, which include but are not limited to enzymes in the glutathione peroxidase, catalase, and superoxide dismutase families, degrade ROS that otherwise damage cellular components such as DNA, proteins, and lipids. Several groups have identified cellular therapies including neural stem cells and human umbilical cord blood cells, which exert neuroprotective and oligoprotective effects through the release of pro-survival factors that activate PI3K/Akt signaling to upregulation of antioxidant enzymes. Other studies demonstrate that treatment with soluble factors released by these cells yield similar changes in enzyme expression after stroke. Treatment with the cytokine leukemia inhibitory factor increases the expression of peroxiredoxin IV and metallothionein III in glia and boosts expression of superoxide dismutase 3 in neurons. Through cell-specific upregulation of these enzymes, LIF and other Akt-inducing factors have the potential to protect multiple cell types against damage from ROS during the early and late phases of ischemic damage

The Role of the Leukemia Inhibitory Factor Receptor in Neuroprotective Signaling

Several neurotropic cytokines relay their signaling through the leukemia inhibitory factor receptor. This 190kDa subunit couples with the 130kDa gp130 subunit to transduce intracellular signaling in neurons and oligodendrocytes that leads to expression of genes associated with neurosurvival. Moreover, activation of this receptor alters the phenotype of immune cells to an anti-inflammatory one. Although cytokines that activate the leukemia inhibitory factor receptor have been studied in the context of neurodegenerative disease, therapeutic targeting of the specific receptor subunit has been understudied in by comparison. This review examines the role of this receptor in the CNS and immune system, and its application in the treatment in stroke and other brain pathologies

Collaborative Filtering with Preferences Inferred from Brain Signals

Collaborative filtering is a common technique in which interaction data from a large number of users are used to recommend items to an individual that the individual may prefer but has not interacted with. Previous approaches have achieved this using a variety of behavioral signals, from dwell time and clickthrough rates to self-reported ratings. However, such signals are mere estimations of the real underlying preferences of the users. Here, we use brain-computer interfacing to infer preferences directly from the human brain. We then utilize these preferences in a collaborative filtering setting and report results from an experiment where brain inferred preferences are used in a neural collaborative filtering framework. Our results demonstrate, for the first time, that brain-computer interfacing can provide a viable alternative for behavioral and self-reported preferences in realistic recommendation scenarios. We also discuss the broader implications of our findings for personalization systems and user privacy.Peer reviewe

Reverse taxonomy for elucidating diversity of insect-associated nematodes: a case study with termites

BACKGROUND: The molecular operational taxonomic unit(MOTU)has recently been applied to microbial and microscopic animal biodiversity surveys. However, in many cases, some of the MOTUs cannot be definitively tied to any of the taxonomic groups in current databases. To surmount these limitations, the concept of "reverse taxonomy" has been proposed, i.e. to primarily list the MOTUs with morphological information, and then identify and/or describe them at genus/species level using subsamples or by re-isolating the target organisms. Nevertheless, the application of "reverse taxonomy" has not been sufficiently evaluated. Therefore, the practical applicability of "reverse taxonomy" is tested using termite-associated nematodes as a model system for phoretic/parasitic organisms which have high habitat specificity and a potential handle (their termite host species) for re-isolation attempts. METHODOLOGY: Forty-eight species (from 298 colonies) of termites collected from the American tropics and subtropics were examined for their nematode associates using the reverse taxonomy method and culturing attempts (morphological identification and further sequencing efforts). The survey yielded 51 sequence types (= MOTUs) belonging to 19 tentatively identified genera. Within these, four were identified based on molecular data with preliminary morphological observation, and an additional seven were identified or characterized from successful culturing, leaving eight genera unidentified. CONCLUSIONS: That 1/3 of the genera were not successfully identified suggests deficiencies in the depth of available sequences in the database and biological characters, i.e. usually isolated as phoretic/parasitic stages which are not available for morphological identification, and too many undiscovered lineages of nematodes. Although there still is the issue of culturability of nematodes, culturing attempts could help to make reverse taxonomy methods more effective. However, expansion of the database, i.e., production of more DNA barcodes tied to biological information by finding and characterizing additional new and known lineages, is necessary for analyzing functional diversity.Natsumi Kanzaki, Robin M. Giblin-Davis, Rudolf H. Scheffrahn, Hisatomo Taki, Alejandro Esquivel, Kerrie A. Davies and E. Allen Herr

The Poststroke Peripheral Immune Response Is Differentially Regulated by Leukemia Inhibitory Factor in Aged Male and Female Rodents

Background. The goal of this study was to determine whether leukemia inhibitory factor (LIF) promotes anti-inflammatory activity after stroke in a sex-dependent manner. Methods. Aged (18-month-old) Sprague-Dawley rats of both sexes underwent sham surgery or permanent middle cerebral artery occlusion (MCAO). Animals received three doses of intravenous LIF (125 μg/kg) or PBS at 6, 24, and 48 h before euthanization at 72 h. Spleen weights were measured immediately following euthanization. Western blot was used to measure protein levels of CCL8, CD11b, CXCL9, CXCL10, IL-12 p40, IL-3, and the LIF receptor (LIFR) in spleen tissue. ELISA was used to measure IL-1β, IL-6, TNFα, and IFNγ in spleen tissue. A Griess Assay was used to indirectly quantify NO levels via measurement of nitrite. Levels of cellular markers and inflammatory mediators were normalized to the baseline (sham) group from each sex. Statistical analysis was performed using two-way ANOVA and followed by Fisher’s LSD post hoc test. Results. Aged female rats showed a significantly lower spleen weight after MCAO, but showed a significant increase in spleen size after LIF treatment. This effect was observed in aged male rats, but not to as great of an extent. CD11b levels were significantly higher in the spleens of MCAO+PBS males compared to their female counterparts, but there was no significant difference in CD11b levels between MCAO+LIF males and females. LIF significantly increased CXCL9 after LIF treatment in aged male and female rats. LIFR and IL-3 were upregulated after LIF treatment in aged females. Splenic nitrate increased after MCAO but decreased after LIF treatment in aged females. Splenic nitrate levels did not increase after MCAO but did increase after LIF treatment in aged males. The following cytokines/chemokines were not altered by sex or treatment: TNFα, IL-6, IL-12 p40, CCL8, IFNγ, and CXCL10. Conclusions. LIF treatment after permanent MCAO induces sex-dependent effects on the poststroke splenic response and the production of proinflammatory cytokines among aged rats

Barriers to using new needles encountered by rural Appalachian people who inject drugs: implications for needle exchange

Background Using a new needle for every injection can reduce the spread of infectious disease among people who inject drugs (PWID). No previous study has examined new needle use barriers among PWIDs residing in the rural Appalachian part of the United States, an area currently in the midst of a heroin epidemic. Objective Therefore, our primary aim was to explore self-reported barriers to using a new needle by PWID attending a needle exchange program (NEP). Methods We conducted a cross-sectional survey of PWID attending two NEPs in rural West Virginia located in the heart of Central Appalachia. A convenience sample of PWID (n = 100) completed the Barriers to Using New Needles Questionnaire. Results The median number of barriers reported was 5 (range 0–19). Fear of arrest by police (72% of PWID “agreed” or “strongly agreed”) and difficulty with purchasing needles from a pharmacy (64% “agreed” or “strongly agreed”) were the most frequently cited barriers. Conclusions/Importance Congruent with previous findings from urban locations, in rural West Virginia, the ability of PWID to use a new needle obtained from a needle exchange for every injection may be compromised by fear of arrest. In addition, pharmacy sales of new needles to PWID may be blunted by an absence of explicit laws mandating nonprescription sales. Future studies should explore interventions that align the public health goals of NEPs with the occupational safety of law enforcement and health outreach goals of pharmacists

Evidence against pain specificity in the dorsal posterior insula

The search for a pain centre in the brain has long eluded neuroscientists. Although many regions of the brain have been shown to respond to painful stimuli, all of these regions also respond to other types of salient stimuli. In a recent paper, Segerdahl et al. (Nature Neuroscience, 2015) claims that the dorsal posterior insula (dpIns) is a pain-specific region based on the observation that the magnitude of regional cerebral blood flow (rCBF) fluctuations in the dpIns correlated with the magnitude of evoked pain. However, such a conclusion is, simply, not justified by the experimental evidence provided. Here we discuss three major factors that seriously question this claim

Qualitative case study of needle exchange programs in the Central Appalachian region of the United States

Background The Central Appalachian region of the United States is in the midst of a hepatitis C virus epi- demic driven by injection of opioids, particularly heroin, with contaminated syringes. In response to this epidemic, several needle exchange programs (NEP) have opened to pro- vide clean needles and other supplies and services to people who inject drugs (PWID). How- ever, no studies have investigated the barriers and facilitators to implementing, operating, and expanding NEPs in less populous areas of the United States. Methods This qualitative case study consisted of interviews with program directors, police chiefs, law enforcement members, and PWID affiliated with two NEPs in the rural state of West Virginia. Interview transcripts were coded inductively and analyzed using qualitative data analysis software. Final common themes related to barriers and facilitators of past program open- ings, current program operations, and future program plans, were derived through a consen- sus of two data coders. Results Both NEPs struggled to find existing model programs, but benefited from broad community support that facilitated implementation. The largest operational barrier was the legal conun- drum created by paraphernalia laws that criminalize syringe possession. However, both PWID and law enforcement appreciated the comprehensive services provided by these pro- grams. Program location and transportation difficulties were additional noted barriers. Future program operations are threatened by funding shortages and bans, but necessitated by unexpected program demand. Conclusion Despite broad community support, program operations are threatened by growing partici- pant volumes, funding shortages, and the federal government’s prohibition on the use of funds to purchase needles. Paraphernalia laws create a legal conundrum in the form of criminal sanctions for the possession of needles, which may inadvertently promote needle sharing and disease transmission. Future studies should examine additional barriers to using clean needles provided by rural NEPs that may blunt the effectiveness of NEPs in pre- venting disease transmission

Cognitive Behavioural Therapy with Exposure and Response Prevention in the treatment of Obsessive-Compulsive Disorder: A systematic review and meta-analysis of randomised controlled trials

© 2021 Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Background: Cognitive behavioural therapy (CBT), incorporating exposure and response prevention (ERP) is widely recognised as the psychological treatment of choice for obsessive-compulsive disorder (OCD). Uncertainty remains however about the magnitude of the effect of CBT with ERP and the impact of moderating factors in patients with OCD. Method: This systematic review and meta-analysis assessed randomised-controlled trials of CBT with ERP in patients of all ages with OCD. The study was preregistered in PROSPERO (CRD42019122311). The primary outcome was end-of-trial OCD symptom scores. The moderating effects of patient-related and study-related factors including type of control intervention and risk of bias were examined. Additional exploratory analyses assessed the effects of treatment fidelity and impact of researcher allegiance. Results: Thirty-six studies were included, involving 2020 patients (537 children/adolescents and 1483 adults) with 1005 assigned to CBT with ERP and 1015 to control conditions. When compared against all control conditions, a large pooled effect size (ES) emerged in favour of CBT with ERP (g = 0.74: 95% CI = 0.51 to 0.97 k = 36), which appeared to diminish with increasing age. While CBT with ERP was more effective than psychological placebo (g = 1.13 95% CI 0.71 to 1.55, k = 10), it was no more effective than other active forms of psychological therapy (g = −0.05: 95% CI -0.27 to 0.16, k = 8). Similarly, whereas CBT with ERP was significantly superior when compared to all forms of pharmacological treatment (g = 0.36: 95% CI 0.7 to 0.64, k = 7), the effect became marginal when compared with adequate dosages of pharmacotherapy for OCD (g = 0.32: 95% CI -0.00 to 0.64, k = 6).A minority of studies (k = 8) were deemed to be at low risk of bias. Moreover, three quarters of studies (k = 28) demonstrated suspected researcher allegiance and these studies reported a large ES (g = 0.95: 95% CI 0.69 to 1.2), while those without suspected researcher allegiance (k = 8) indicated that CBT with ERP was not efficacious (g = 0.02: 95% CI -0.29 to 0.33). Conclusions: A large effect size was found for CBT with ERP in reducing the symptoms of OCD, but depends upon the choice of comparator control. This meta-analysis also highlights concerns about the methodological rigor and reporting of published studies of CBT with ERP in OCD. In particular, efficacy was strongly linked to researcher allegiance and this requires further future investigation.Peer reviewe