A hexanucleotide GGGGCC repeat expansion in the noncoding region of the C9ORF72 gene is the most common genetic abnormality in familial and sporadic amyotrophic lateral sclerosis (ALS) and ...frontotemporal dementia (FTD). The function of the C9ORF72 protein is unknown, as is the mechanism by which the repeat expansion could cause disease. Induced pluripotent stem cell (iPSC)-differentiated neurons from C9ORF72 ALS patients revealed disease-specific (1) intranuclear GGGGCCexp RNA foci, (2) dysregulated gene expression, (3) sequestration of GGGGCCexp RNA binding protein ADARB2, and (4) susceptibility to excitotoxicity. These pathological and pathogenic characteristics were confirmed in ALS brain and were mitigated with antisense oligonucleotide (ASO) therapeutics to the C9ORF72 transcript or repeat expansion despite the presence of repeat-associated non-ATG translation (RAN) products. These data indicate a toxic RNA gain-of-function mechanism as a cause of C9ORF72 ALS and provide candidate antisense therapeutics and candidate human pharmacodynamic markers for therapy.
•iPSC neurons mirror dysregulated gene expression in C9ORF72 brain•Aggregated RNA binding proteins contribute to toxicity•C9ORF72 iPSC neurons are highly susceptible to excitotoxicity.•Pathology and toxicity is abrogated with antisense to C9ORF72 expansion
Donnelly et al. provide evidence for RNA toxicity, through the use of induced pluripotent cells, as the cause of amyotrophic lateral sclerosis and frontotemporal dementia in patients with mutation in the C9ORF72 gene and a cellular rescue using antisense oligonucleotide therapy.
The increased severity of white matter disease is associated with worse outcomes and an increased rate of intracerebral hemorrhage in patients with ischemic stroke undergoing thrombolytic treatment. ...However, whether white matter disease is associated with outcomes in patients undergoing endovascular treatment remains unclear.
In this prespecified exploratory analysis of our prospective multi-institutional study that enrolled consecutive adult patients with anterior circulation ischemic stroke undergoing endovascular treatment from November 2017 to September 2018, we compared the following outcomes between patients with none-to-minimal (van Swieten score, 0-2) and moderate-to-severe (van Swieten score, 3-4) white matter disease using logistic regression: 90-day mRS 3-6, death, intracerebral hemorrhage, successful recanalization, and early neurologic recovery.
Of the 485 patients enrolled in the Blood Pressure after Endovascular Stroke Therapy (BEST) study, 389 had white matter disease graded (50% women; median age, 68 years; range, 58-79 years). A van Swieten score of 3-4 (
= 74/389, 19%) was associated with a higher rate of 90-day mRS of 3-6 (45% versus 18%; adjusted OR, 2.73; 95% CI, 1.34-5.93;
= .008). Although the death rate was higher in patients with van Swieten scores of 3-4 (26% versus 15%), the adjusted likelihood was not significantly different (adjusted OR, 1.14; 95% CI, 0.56-2.26;
= .710). Ordered regression revealed a shift toward worse mRS scores with increasing van Swieten scores (adjusted common OR, 3.04; 95% CI, 1.93-4.84;
< .001). No associations between white matter disease severity and intracerebral hemorrhage, successful recanalization, and early neurologic recovery were observed.
Moderate-to-severe white matter disease is associated with worse outcomes in patients undergoing endovascular treatment without a significant increase in hemorrhagic complications. Studies comparing patients with and without endovascular treatment are necessary to determine whether the benefit of endovascular treatment is attenuated with greater white matter disease.
Laser welding of aluminium alloys typically results in porosity in the fusion zones, leading to poor mechanical and corrosion performances. Mechanical and chemical cleaning of surfaces has been used ...previously to remove contaminants for weld joint preparations. However, these methods are slow, ineffective (e.g. due to hydrogen trapping) or lead to environmental hazards. This paper reports the effects of short pulsed laser surface cleaning on porosity formation and reduction in laser welding of AC-170PX (AA6014) aluminium sheets (coated with Ti/Zr and lubricated using a dry lubricant AlO70) with two types of joints: fillet edge and flange couch, using an AA4043 filler wire for automotive component assembly. The effect of laser cleaning on porosity reduction during laser welding using a filler wire has not been reported before. In this work, porosity and weld fusion zone geometry were examined prior to and after laser cleaning. The nanosecond pulsed Nd:YAG laser cleaning was found to reduce porosity significantly in the weld fusion zones. For the fillet edge welds, porosity was reduced to less than 0.5% compared with 10–80% without laser cleaning. For flange couch welds, porosity was reduced to 0.23–0.8% with laser cleaning from 0.7% to 4.3% without laser cleaning. This has been found to be due to the elimination of contaminations and oxide layers that contribute to the porosity formation. The laser cleaning is based on thermal ablation.
•This research focuses on porosity reduction in laser welding of aluminium alloy.•Weld quality was investigated for two joints, fillet edge and flange couch joints.•The effect of laser cleaning on porosity reduction after welding was investigated.•It was found that laser cleaning reduced porosity less than 1% in both joints.•Weld dimensions and strength were evaluated and discussed for both types of joints.
Current guidelines suggest treating blood pressure above 180/105 mm Hg during the first 24 hours in patients with acute ischemic stroke undergoing any form of recanalization therapy. Currently, no ...studies exist to guide blood pressure management in patients with stroke treated specifically with mechanical thrombectomy. We aimed to determine the association between blood pressure parameters within the first 24 hours after mechanical thrombectomy and patient outcomes.
We retrospectively studied a consecutive sample of adult patients who underwent mechanical thrombectomy for acute ischemic stroke of the anterior cerebral circulation at 3 institutions from March 2015 to October 2016. We collected the values of maximum, minimum, and average values of systolic blood pressure, diastolic blood pressure, and mean arterial pressures in the first 24 hours after mechanical thrombectomy. Primary and secondary outcomes were patients' functional status at 90 days measured on the modified Rankin scale and the incidence and severity of intracranial hemorrhages within 48 hours. Associations were explored using an ordered multivariable logistic regression analyses. A total of 228 patients were included (mean age 65.8±14.3; 104 males, 45.6%). Maximum systolic blood pressure independently correlated with a worse 90-day modified Rankin scale and hemorrhagic complications within 48 hours (adjusted odds ratio=1.02 1.01-1.03,
=0.004; 1.02 1.01-1.04,
=0.002; respectively) in multivariable analyses, after adjusting for several possible confounders.
Higher peak values of systolic blood pressure independently correlated with worse 90-day modified Rankin scale and a higher rate of hemorrhagic complications. Further prospective studies are warranted to identify whether systolic blood pressure is a therapeutic target to improve outcomes.
Lateral flow devices (LFDs) are viral antigen tests for the detection of SARS-CoV-2 that produce a rapid result, are inexpensive and easy to operate. They have been advocated for use by the World ...Health Organisation to help control outbreaks and break the chain of transmission of COVID-19 infections. There are now several studies assessing their accuracy but as yet no systematic review. Our aims were to assess the sensitivity and specificity of LFDs in a systematic review and summarise the sensitivity and specificity of these tests. A targeted search of Pubmed and Medxriv, using PRISMA principles, was conducted identifying clinical studies assessing the sensitivity and specificity of LFDs as their primary outcome compared to reverse transcriptase polymerase chain reaction (RT-PCR) for the detection of SARS-CoV-2. Based on extracted data sensitivity and specificity was calculated for each study. Data was pooled based on manufacturer of LFD and split based on operator (self-swab or by trained professional) and sensitivity and specificity data were calculated. Twenty-four papers were identified involving over 26,000 test results. Sensitivity from individual studies ranged from 37.7% (95% CI 30.6-45.5) to 99.2% (95% CI 95.5-99.9) and specificity from 92.4% (95% CI 87.5-95.5) to 100.0% (95% CI 99.7-100.0). Operation of the test by a trained professional or by the test subject with self-swabbing produced comparable results. This systematic review identified that the performance of lateral flow devices is heterogeneous and dependent on the manufacturer. Some perform with high specificity but a great range of sensitivities were shown (38.32-99.19%). Test performance does not appear dependent on the operator. Potentially, LFDs could support the scaling up of mass testing to aid track and trace methodology and break the chain of transmission of COVID-19 with the additional benefit of providing individuals with the results in a much shorter time frame.
Large vessel occlusion stroke due to underlying intracranial atherosclerotic disease (ICAD-LVO) is prevalent in 10 to 30% of LVOs depending on patient factors such as vascular risk factors, race and ...ethnicity, and age. Patients with ICAD-LVO derive similar functional outcome benefit from endovascular thrombectomy as other mechanisms of LVO, but up to half of ICAD-LVO patients reocclude after revascularization. Therefore, early identification and treatment planning for ICAD-LVO are important given the unique considerations before, during, and after endovascular thrombectomy. In this review of ICAD-LVO, we propose a multistep approach to ICAD-LVO identification, pretreatment and endovascular thrombectomy considerations, adjunctive medications, and medical management. There have been no large-scale randomized controlled trials dedicated to studying ICAD-LVO, therefore this review focuses on observational studies.
Th17 cells are potent mediators in autoimmune diseases, and RORγt is required for their development. Recent studies have shown that RORγt+ Treg cells in the gut regulate intestinal inflammation by ...inhibiting effector T cell function. In the current study, we report that RORγt+ Treg cells were also found in lymph nodes following immunization. Not only distinct from intestinal RORγt+ Treg cells in their transcriptomes, peripheral RORγt+ Treg cells were derived from Foxp3+ thymic Treg cells in an antigen-specific manner. Development of these RORγt+ Treg cells, coined T regulatory 17 (Tr17) cells, depended on IL-6/Stat3 signaling. Tr17 cells showed suppressive activity against antigen-specific effector T cells in vitro. In addition, Tr17 cells efficiently inhibited myelin-specific Th17-cell-mediated CNS auto-inflammation in a passive EAE model. Collectively, our study demonstrates that Tr17 cells are effector Treg cells that potentially restrict autoimmunity.
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•RORγt+Foxp3+CD4+ Tr17 cells are found in lymph nodes after immunization•Tr17 cells upregulate Treg cell-associated effector molecules and CCR6•Tr17 cells originate from resting Treg cells via Stat3 signaling•Tr17 cells potentially modulate Th17-cell-driven CNS autoimmunity
Kim et al. find that RORγt+Foxp3+ T regulatory 17 (Tr17) cells are induced in lymph nodes after immunization. Tr17 cells are generated from thymic Treg cells in an antigen-specific manner through Stat3 signaling. Their data suggest that Tr17 cells represent antigen-specific effector Treg cells that can regulate Th17-cell-dependent autoimmunity.