Diagnosis of osteochondral lesions of the talus on Dual-layer spectral detector CT arthrography: clinical feasibility of virtual noncontrast images

AIM

To compare the image quality of virtual noncontrast (VNC) and true noncontrast (TNC) CT images and to evaluate the clinical feasibility of VNC CT images for assessing osteochondral lesions of the talus (OLTs).

MATERIALS AND METHODS

Forty-five OLT patients who underwent ankle CT arthrography (CTA) using dual-layer spectral detector CT were enrolled. Reconstruction of VNC and three-dimensional volume rendering images was performed. Afterward, image noise, the signal-to-noise ratio (SNR), and the contrast-to-noise ratio (CNR) were measured. For the subjective evaluation, two board-certified musculoskeletal radiologists [R2-1] assessed spatial resolution, overall image quality, and lesion conspicuity. The accuracy rate for OLT grading was determined in 23 patients who underwent arthroscopic surgery.

RESULTS

While VNC images showed significantly less noise than TNC images, TNC images showed better SNRs and CNRs (p<.01). In the subjective analysis, TNC images showed better overall image quality (p<.001). For the 3D volume rendering images, VNC images scored significantly higher for lesion conspicuity (p<.001). The accuracy rates of CTA and CTA with VNC images for OLT grading were 79.2% and 83.3%, respectively. Regarding confidence level, when CTA and VNC images were evaluated together, the confidence level was significantly higher than that when only CTA images were evaluated (p<.001).

CONCLUSION

VNC imaging can provide better confidence level of OLT grading and evaluation of the integrity of the subchondral bone plate when combined with conventional CTA without additional radiation dose to the patient. In addition, VNC images-based 3D volume rendering reconstruction would be helpful for preoperative planning in OLT patients.

Neutrophils and Neutrophil Extracellular Traps Cause Vascular Occlusion and Delayed Cerebral Ischemia After Subarachnoid Hemorrhage in Mice

BACKGROUND

After subarachnoid hemorrhage (SAH), neutrophils are deleterious and contribute to poor outcomes. Neutrophils can produce neutrophil extracellular traps (NETs) after ischemic stroke. Our hypothesis was that, after SAH, neutrophils contribute to delayed cerebral ischemia (DCI) and worse outcomes via cerebrovascular occlusion by NETs.

METHODS

SAH was induced via endovascular perforation, and SAH mice were given either a neutrophil-depleting antibody, a PAD4 (peptidylarginine deiminase 4) inhibitor (to prevent NETosis), DNAse-I (to degrade NETs), or a vehicle control. Mice underwent daily neurological assessment until day 7 and then euthanized for quantification of intravascular brain NETs (iNETs). Subsets of mice were used to quantify neutrophil infiltration, NETosis potential, iNETs, cerebral perfusion, and infarction. In addition, NET markers were assessed in the blood of aneurysmal SAH patients.

RESULTS

In mice, SAH led to brain neutrophil infiltration within 24 hours, induced a pro-NETosis phenotype selectively in skull neutrophils, and caused a significant increase in iNETs by day 1, which persisted until at least day 7. Neutrophil depletion significantly reduced iNETs, improving cerebral perfusion, leading to less neurological deficits and less incidence of DCI (16% versus 51.9%). Similarly, PAD4 inhibition reduced iNETs, improved neurological outcome, and reduced incidence of DCI (5% versus 30%), whereas degrading NETs marginally improved outcomes. Patients with aneurysmal SAH who developed DCI had elevated markers of NETs compared with non-DCI patients.

CONCLUSIONS

After SAH, skull-derived neutrophils are primed for NETosis, and there are persistent brain iNETs, which correlated with delayed deficits. The findings from this study suggest that, after SAH, neutrophils and NETosis are therapeutic targets, which can prevent vascular occlusion by NETs in the brain, thereby lessening the risk of DCI. Finally, NET markers may be biomarkers, which can predict which patients with aneurysmal SAH are at risk for developing DCI.

Integrated inflammatory signaling landscape response after delivering Elovanoid free-fatty-acid precursors leading to experimental stroke neuroprotection

Despite efforts to identify modulatory neuroprotective mechanisms of damaging ischemic stroke cascade signaling, a void remains on an effective potential therapeutic. The present study defines neuroprotection by very long-chain polyunsaturated fatty acid (VLC-PUFA) Elovanoid (ELV) precursors C-32:6 and C-34:6 delivered intranasally following experimental ischemic stroke. We demonstrate that these precursors improved neurological deficit, decreased T2WI lesion volume, and increased SMI-71 positive blood vessels and NeuN positive neurons, indicating blood-brain barrier (BBB) protection and neurogenesis modulated by the free fatty acids (FFAs) C-32:6 and C-34:6. Gene expression revealed increased anti-inflammatory and pro-homeostatic genes and decreases in expression of pro-inflammatory genes in the subcortex. Additionally, the FFAs elicit a comprehensive downregulation of inflammatory microglia/monocyte-derived macrophages and astrocyte-associated genes in the subcortical region. Functional analysis reveals inhibition of immune-related pathways and production of upstream molecules related to detrimental signaling events in post-stroke acute and subacute phases.

Anti-diabetic effect of quercetin in type 2 diabetes mellitus by regulating the microRNA-92b-3p/EGR1 axis

Insulin resistance (IR) is predominantly causal for type 2 diabetes mellitus (T2DM). To solve this problem, this study particularly determined the role of quercetin (Que) in controlling IR in T2DM mice. The T2DM mouse model was established, and given 20 mg/kg/d Que by gavage for 6 weeks, and the lentiviral vector that interfered with microRNA-92b-3p (miR-92b-3p) or early growth response 1 (EGR1) expression was injected into the tail vein of T2DM mice. Blood glucose homeostasis and histopathological changes in the pancreas were observed after the corresponding treatment. miR-92b-3p and EGR1 expressions were assessed in T2DM mice, as well as their interlink. In results we found that Que could improve IR and pancreatic histopathological changes in T2DM mice. Low miR-92b-3p and high EGR1 were expressed in T2DM mice, while Que could upregulate miR-92b-3p to target EGR1. Enhancing miR-92b-3p or reducing EGR1 could further improve IR and pancreatic histopathological changes in T2DM mice after Que administration. Nevertheless, silencing miR-92b-3p or overexpressing EGR1 contributed to the opposite results. We concluded that Que exerted anti-diabetic effects in T2DM mice by regulating the miR-92b-3p/EGR1 axis.

Opportunities of Electronic and Optical Sensors in Autonomous Medical Plasma Technologies

Low temperature plasma technology is proving to be at the frontier of emerging medical technologies with real potential to overcome escalating healthcare challenges including antimicrobial and anticancer resistance. However, significant improvements in efficacy, safety, and reproducibility of plasma treatments need to be addressed to realize the full clinical potential of the technology. To improve plasma treatments recent research has focused on integrating automated feedback control systems into medical plasma technologies to maintain optimal performance and safety. However, more advanced diagnostic systems are still needed to provide data into feedback control systems with sufficient levels of sensitivity, accuracy, and reproducibility. These diagnostic systems need to be compatible with the biological target and to also not perturb the plasma treatment. This paper reviews the state-of-the-art electronic and optical sensors that might be suitable to address this unmet technological need, and the steps needed to integrate these sensors into autonomous plasma systems. Realizing this technological gap could facilitate the development of next-generation medical plasma technologies with strong potential to yield superior healthcare outcomes.

Measurement of Uninterrupted Cerebral Blood Flow by Laser Speckle Contrast Imaging (LSCI) During the Mouse Middle Cerebral Artery Occlusion Model by an Inverted LSCI Setup

Laser speckle contrast imaging (LSCI) offers the ability to measure relative cerebral blood flow (CBF) through the intact skull in mice. LSCI can be used to measure changes in cortical CBF in the middle cerebral artery occlusion/reperfusion (MCAo/R) stroke model. However, because conventional LSCI approaches are designed to image from above, uninterrupted measurement of CBF during the MCAo/R procedure is not possible due to the need to repeatedly reposition the mouse between prone and supine positions. We present a modified method to perform LSCI measurement from beneath the surgical preparation, thus allowing uninterrupted measurement of relative CBF from baseline through re-introduction of blood flow. We provide a 3D printable imaging platform and corresponding head frame, as well as methods to improve skull clarity in young and aged mice.

Targeting Hemoglobin to Reduce Delayed Cerebral Ischemia After Subarachnoid Hemorrhage

Delayed cerebral ischemia (DCI) continues to be a sequela of aneurysmal subarachnoid hemorrhage (aSAH) that carries significant morbidity and mortality. Aside from nimodipine, no therapeutic agents are available to reduce the incidence of DCI. Pathophysiologic mechanisms contributing to DCI are poorly understood, but accumulating evidence over the years implicates several factors. Those have included microvessel vasoconstriction, microthrombosis, oxidative tissue damage, and cortical spreading depolarization as well as large vessel vasospasm. Common to these processes is red blood cell leakage into the cerebrospinal fluids (CSF) and subsequent lysis which releases hemoglobin, a central instigator in these events. This has led to the hypothesis that early blood removal may improve clinical outcome and reduce DCI. This paper will provide a narrative review of the evidence of hemoglobin as an instigator of DCI. It will also elaborate on available human data that discuss blood clearance and CSF drainage as a treatment of DCI. Finally, we will address a recent novel device that is currently being tested, the Neurapheresis CSF Management System™. This is an automated dual-lumen lumbar drainage system that has an option to filter CSF and return it to the patient.

COVID-19 susceptibility and clinical outcomes in autoimmune inflammatory rheumatic diseases (AIRDs): a systematic review and meta-analysis

OBJECTIVE

This meta-analysis aims to assess the susceptibility to and clinical outcomes of COVID-19 in autoimmune inflammatory rheumatic disease (AIRD) and following AIRD drug use.

MATERIALS AND METHODS

We included observational and case-controlled studies assessing susceptibility and clinical outcomes of COVID-19 in patients with AIRD as well as the clinical outcomes of COVID-19 with or without use of steroids and conventional synthetic disease-modifying antirheumatic drugs (csDMARDs).

RESULTS

Meta-analysis including three studies showed that patients with AIRD are not more susceptible to COVID-19 compared to patients without AIRD or the general population (OR: 1.11, 95% CI: 0.58 to 2.14). Incidence of severe outcomes of COVID-19 (OR: 1.34, 95% CI: 0.76 to 2.35) and COVID-19 related death (OR: 1.21, 95% CI: 0.68 to 2.16) also did not show significant difference. The clinical outcomes of COVID-19 among AIRD patients with and without csDMARD or steroid showed that both use of steroid (OR: 1.69, 95% CI: 0.96 to 2.98) or csDMARD (OR: 1.35, 95% CI: 0.63 to 3.08) had no effect on clinical outcomes of COVID-19.

CONCLUSIONS

AIRD does not increase susceptibility to COVID-19, not affecting the clinical outcome of COVID-19. Similarly, the use of steroids or csDMARDs for AIRD does not worsen the clinical outcome.

Continuing perioperative estrogen therapy does not increase venous thromboembolic events in transgender patients: a systematic review and meta-analysis

OBJECTIVE

The aim of this study is to compare the risk of venous thromboembolic events (VTE) between patients suspending and continuing estrogen therapy perioperatively, in male to female gender-affirming surgery (vaginoplasty).

MATERIALS AND METHODS

The authors conducted a systematic review and meta-analysis of existing research on male to female gender-affirming study, which compared the risk of VTE among the usage of estrogen perioperatively.

RESULTS

A total of 209 studies were identified as potentially eligible among PubMed, Embase, and Cochrane library databases. Among the studies, 191 studies were excluded due to their abstract inappropriateness. Out of the remaining 18 studies, only 3 articles were eligible and were finally included. Meta-analysis was performed and showed odds ratio of 0.77 (95% CI: 0.04, 14.01).

CONCLUSIONS

Perioperative estrogen therapy does not increase VTE risk on male to female gender-affirming surgery. Therefore, estrogen therapy may be continued perioperatively in vaginoplasty. More prospective studies are needed.

Abstract WMP111: Microvascular Occlusion Precedes Delayed Deficits In Mice With Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) induces delayed cerebral ischemia (DCI) in about 30% of patients which is characterized by functional decline. Microvascular occlusion, via microvessel constriction or microthrombi, may be a cause of DCI. Our hypothesis is that microvascular occlusion and reduced cerebral blood flow (CBF) precede the onset of delayed deficits in mice with SAH. Mice were randomly assigned into sham, SAH+saline, and SAH+A3P5P+Clopidogrel (platelet antagonists). Laser speckle imaging (to assess large and microvessel perfusion) and behavior were assessed daily. All outcomes were performed and data was analyzed by a blinded investigator. Both large artery and microvessel/tissue perfusion recover to baseline in SAH mice which do not get delayed deficits. However, in SAH mice which develop delayed deficits, microvessel/tissue perfusion has a prolonged reduction (Figure 1A). Interestingly, large artery perfusion recovers in these mice. Antiplatelets prevent microthrombi, attenuating microvessel occlusion, and reduce delayed deficits (Figure 2B-C). Our findings suggest that 1) microvessel occlusion and prolonged tissue perfusion are causative factors for DCI and 2) preventing platelet activation may be a therapeutic target to reduce the incidence of DCI. Our data also suggests a sex difference in the response to platelet antagonists (data not shown).

Suicide associated with COVID-19 infection: an immunological point of view

OBJECTIVE

Coronavirus disease 2019 (COVID-19) is a pandemic and leading cause of death. Beyond the deaths directly caused by the virus and the suicides related to the psychological response to the dramatic changes as socioeconomic related to the pandemic, there might also be suicides related to the inflammatory responses of the infection. Infection induces inflammation as a cytokine storm, and there is an increasing number of studies that report a relationship between infection and suicide.

MATERIALS AND METHODS

We searched the World Health Organization status report and the PubMed database for keywords (COVID-19, suicide, infection, inflammation, cytokines), and reviewed five cytokine pathways between suicide and inflammation using two meta-analyses and two observational studies starting from November 31, 2020, focusing on the relationship between suicide and inflammation by infection. First, we discussed existing evidence explaining the relationship between suicidal behaviors and inflammation. Second, we summarized the inflammatory features found in COVID-19 patients. Finally, we highlight the potential for these factors to affect the risk of suicide in COVID-19 patients.

RESULTS

Patients infected with COVID-19 have high amounts of IL-1β, IFN-γ, IP10, and MCP1, which may lead to Th1 cell response activation. Also, Th2 cytokines (e.g., IL-4 and IL-10) were increased in COVID-19 infection. In COVID-19 patients, neurological conditions, like headache, dizziness, ataxia, seizures, and others have been observed.

CONCLUSIONS

COVID-19 pandemic can serve as a significant environmental factor contributing directly to increased suicide risk; the role of inflammation by an infection should not be overlooked.

Efficacy and safety of epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) monotherapy for advanced EGFR-mutated non-small cell lung cancer: systematic review and meta-analysis

OBJECTIVE

It is controversial whether there is efficacy or safety benefit of epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) in advanced EGFR-mutated non-small cell lung cancer (NSCLC) compared to standard chemotherapy. We aim to assess the efficacy and safety of EGFR-TKIs compared to other chemotherapeutics in EGFR-mutated NSCLC.

MATERIALS AND METHODS

Up to April 27th, 2020, PubMed, Embase, Medline, Scopus, Cochrane library, and ClinicalTrials.gov were searched for articles or trials meeting the inclusion criteria. After filtering, 230 eligible studies were initially identified. Data extraction followed PRISMA and included outcomes were progression-free survival (PFS), overall survival (OS), and severe adverse events (SAEs). Direct and indirect meta-analyses were generated in the context of log-linear mixed-effects models, with fixed effects for each relative comparison and random effects for each study.

RESULTS

The results showed that EGFR-TKI therapy had improved PFS with a hazard ratio (HR) of 0.40 (95% CI: 0.36-0.44, p<0.001) compared to standard chemotherapy. Nevertheless, the EGFR-TKIs showed no benefit on OS (HR: 0.96, 95% CI: 0.83-1.10, p=0.556). In the analysis of adverse events, EGFR-TKIs had fewer SAEs than standard chemotherapy (HR: 0.29, 95% CI: 0.26-0.33, p<0.001).

CONCLUSIONS

Our systemic review indicates that EGFR-TKI therapy has improved PFS, and reduced SAEs compared to standard chemotherapy in advanced EGFR-mutated NSCLC.

Empirical assessment of biases in cerebrospinal fluid biomarkers of Alzheimer's disease: an umbrella review and re-analysis of data from meta-analyses

OBJECTIVE

Alzheimer's disease (AD) is a leading cause of years lived with disability in older age, and several cerebrospinal fluid (CSF) markers have been proposed in individual meta-analyses to be associated with AD but field-wide evaluation and scrutiny of the literature is not available.

MATERIALS AND METHODS

We performed an umbrella review for the reported associations between CSF biomarkers and AD. Data from available meta-analyses were reanalyzed using both random and fixed effects models. We also estimated between-study heterogeneity, small-study effects, excess significance, and prediction interval.

RESULTS

A total of 38 meta-analyses on CSF markers from 11 eligible articles were identified and reanalyzed. In 14 (36%) of the meta-analyses, the summary estimate and the results of the largest study showed non-concordant results in terms of statistical significance. Large heterogeneity (I2≥75%) was observed in 73% and small-study effects under Egger's test were shown in 28% of CSF biomarkers.

CONCLUSIONS

Our results suggest that there is an excess of statistically significant results and significant biases in the literature of CSF biomarkers for AD. Therefore, the results of CSF biomarkers should be interpreted with caution.

Body mass index and mortality in patients with cardiovascular disease: an umbrella review of meta-analyses

OBJECTIVE

Although many previous meta-analyses of epidemiological studies have demonstrated a relationship between body mass index (BMI) and mortality, inconsistent findings among cardiovascular disease patients have been observed. Thus, we performed an umbrella review to understand the strength of evidence and validity of claimed associations between BMI and mortality in patients with cardiovascular diseases.

MATERIALS AND METHODS

We comprehensively re-analyzed the data of meta-analyses of observational studies and randomized controlled trials on associations between BMI and mortality among patients with cardiovascular diseases. We also assessed the strength of evidence of the re-analyzed outcomes, which were determined from the criteria including statistical significance of the p-value of random-effects, as well as fixed-effects meta-analyses, small-study effects, between-study heterogeneity, and a 95% prediction interval.

RESULTS

We ran comprehensive re-analysis of the data from the 21 selected studies, which contained a total of 108 meta-analyses; 23 were graded as convincing evidence and 12 were suggestive, 42 were weak, and 23 were non-significant.

CONCLUSIONS

Underweight increased mortality in acute coronary syndrome (ACS), heart failure, and after therapeutic intervention for patients with cardiovascular diseases. Overweight, on the other hand decreased mortality in patient's ACS, atrial fibrillation, and heart failure with convincing evidence.

A low-cost mouse cage warming system provides improved intra-ischemic and post-ischemic body temperature control - Application for reducing variability in experimental stroke studies

BACKGROUND

Brain temperature is a strong determinant of ischemic stroke injury. For this reason, tight management of brain or body temperature (Tcore) in experimental rodent stroke models is recommended to improve the rigor and reproducibility of outcomes. However, methods for managing Tcore during and after stroke vary widely in approach and effectiveness.

NEW METHOD

We developed a low-cost warm ambient air cage (WAAC) system to provide improved temperature control during the intra-ischemic and post-ischemic recovery periods. The system is incorporated into standard holding cages for maintaining Tcore during the intra-ischemic period as well as for several hours into the recovery period.

RESULTS AND COMPARISON WITH EXISTING METHODS

We compared the WAAC system with a commonly used heat support method, consisting of a cage on a heating pad. Both heat support systems were evaluated for the middle cerebral artery occlusion (MCAo) stroke model in mice. The WAAC system provided improved temperature control (more normothermic Tcore and less Tcore variation) during the intra- ischemic period (60 min) and post-ischemic period (3 h). Mean infarct volume was not statistically different by heat support system, however, standard deviation was 54 % lower in the WAAC system group.

CONCLUSIONS

Mice and other small rodents are highly vulnerable to heat loss during and after the MCAo procedure. The WAAC system provides more precise and controlled Tcore maintenance compared with frequently used induction heating methods in mice undergoing the MCAo stroke model. The improved temperature control should enhance experimental rigor and reduce the number of experimental animals needed.

Minimally Invasive Spine Surgery versus Open Posterior Instrumentation Surgery for Unstable Thoracolumbar Burst Fracture

Study Design

Retrospective study.

Purpose

To compare the clinical and radiological results of minimally invasive spine surgery (MISS) and open posterior instrumentation surgery for the treatment of unstable burst fractures.

Overview of Literature

MISS has exhibited postoperative outcomes similar to those obtained using open posterior instrumentation in various spine diseases. There remains no consensus regarding the use of MISS in the treatment of unstable burst fracture.

Methods

We enrolled 40 patients who underwent either MISS (M group, 20 patients) or open posterior instrumentation surgery (O group, 20 patients) for the treatment of traumatic unstable burst fractures. Clinical outcomes were evaluated based on postoperative back pain, operation time, blood loss, hospital stay duration, and perioperative complications. For radiologic evaluation, preoperative magnetic resonance imaging and plain radiography were performed before and after the surgery to evaluate the changes in the kyphotic angle and fracture union.

Results

The change in the kyphotic angle was −8.2°±5.8° in the M group and −8.0°±7.8° in the O group. No significant difference was noted in terms of the change in the kyphotic angle (p=0.94, t-test) after 12 months of surgery. The Visual Analog Scale score was 1.5±0.7 points in the M group, while it was 5.2±1.4 points in the O group. In the M group, back pain has significantly decreased (p<0.01, t-test). The estimated blood loss was 195.5 mL in the M group and 1,077.5 mL in the O group; the operation time was significantly decreased in the O group from 290.7 to 120.7 minutes in the M group (p<0.05, t-test) (p=0.36, t-test). The average duration of hospital stay was 36.0 days in the M group and 41.9 days in the O group (p=0.36, t-test).

Conclusions

For the treatment of unstable burst fractures, MISS showed significant differences in terms of postoperative back pain, operation time, and blood loss as compared to open posterior instrumentation surgery.

Data analysis scheme for correcting general misalignments of an optics configuration for a voltage measurement system based on the Pockels electro-optic effect

Having a sub-ns response time and not requiring physical contacts to the measurement points, a voltage measurement system based on the Pockels electro-optic effect, referred to as a PE (Pockels effect)-based voltmeter, is widely used for pulsed high voltage devices such as accelerators and X-pinch systems. To correct for the misalignment of a Pockels cell and the transmittance ratio of a beam splitter, a polar-coordinate-based data analysis scheme has been proposed. This scheme also overcomes a limitation on the measurable range of a PE-based voltmeter without ambiguity and can measure the half-wave voltage of a Pockels cell. We present an improved polar-coordinate-based data analysis scheme using an ellipse fitting method, which can correct for misalignments of all the optics components of a PE-based voltmeter while keeping the advantages of the previous scheme. We show the results of the improved data analysis scheme for measuring a slowly modulated voltage up to approximately 5 kV in about 30 s and a pulsed high voltage up to 7 kV with a rise time of less than 20 ns.

Risk factors of COVID-19 mortality: a systematic review of current literature and lessons from recent retracted articles

OBJECTIVE

Recently, two influential articles that reported the association of (hydroxy)chloroquine or angiotensin converting enzyme (ACE) inhibitors and coronavirus disease 2019 (COVID-19) mortality were retracted due to significant methodological issues. Therefore, we aimed to analyze the same clinical issues through an improved research method and to find out the differences from the retracted papers. We systematically reviewed pre-existing literature, and compared the results with those of the retracted papers to gain a novel insight.

MATERIALS AND METHODS

We extracted common risk factors identified in two retracted papers, and conducted relevant publication search until June 26, 2020 in PubMed. Then, we analyzed the risk factors for COVID-19 mortality and compared them to those of the retracted papers.

RESULTS

Our systematic review demonstrated that most demographic and clinical risk factors for COVID-19 mortality were similar to those of the retracted papers. However, while the retracted paper indicated that both (hydroxy)chloroquine monotherapy and combination therapy with macrolide were associated with higher risk of mortality, our study showed that only combination therapy of hydroxychloroquine and macrolide was associated with higher risk of mortality (odds ratio 2.33; 95% confidence interval 1.63-3.34). In addition, our study demonstrated that use of ACE inhibitors or angiotensin receptor blockers (ARBs) was associated with reduced risk of mortality (0.77; 0.65-0.91).

CONCLUSIONS

When analyzing the same clinical issues with the two retracted papers through a systematic review of randomized controlled trials and relevant cohort studies, we found out that (hydroxy)chloroquine monotherapy was not associated with higher risk of mortality, and that the use of ACE inhibitors or ARBs was associated with reduced risk of mortality in COVID-19 patients.

Clinical characteristics and mortality of patients with hematologic malignancies and COVID-19: a systematic review

OBJECTIVE

Hematologic cancer patients with Coronavirus Disease 2019 (COVID-19) tend to have a more serious disease course than observed in the general population. Herein, we comprehensively reviewed existing literature and analyzed clinical characteristics and mortality of patients with hematologic malignancies and COVID-19.

MATERIALS AND METHODS

Through searching PubMed until June 03, 2020, we identified 16 relevant case studies (33 cases) from a total of 45 studies that have reported on patients with COVID-19 and hematologic malignancies. We investigated the clinical and laboratory characteristics including type of hematologic malignancies, initial symptoms, laboratory findings, and clinical outcomes. Then, we compared those characteristics and outcomes of patients with hematologic malignancies and COVID-19 to the general population infected with COVID-19.

RESULTS

The median age was 66-year-old. Chronic lymphocytic leukemia was the most common type of hematologic malignancy (39.4%). Fever was the most common symptom (75.9%). Most patients had normal leukocyte counts (55.6%), lymphocytosis (45.4%), and normal platelet counts (68.8%). In comparison to patients with COVID-19 without underlying hematologic malignancies, dyspnea was more prevalent (45.0 vs. 24.9%, p=0.025). Leukocytosis (38.9 vs. 9.8%, p=0.001), lymphocytosis (45.4 vs. 8.2%, p=0.001), and thrombocytopenia (31.3 vs. 11.4%, p=0.036) were significantly more prevalent and lymphopenia (18.2 vs. 57.4%, p=0.012) less prevalent in patients with hematologic malignancies. There were no clinical and laboratory characteristics predicting mortality in patients with hematologic malignancies. Mortality was much higher in patients with hematologic malignancies compared to those without this condition (40.0 vs. 3.6%, p<0.001).

CONCLUSIONS

Co-occurrence of hematologic malignancies and COVID-19 is rare. However, due to the high mortality rate from COVID-19 in this vulnerable population, further investigation on tailored treatment and management is required.

DHA modulates MANF and TREM2 abundance, enhances neurogenesis, reduces infarct size, and improves neurological function after experimental ischemic stroke

Aims

Mesencephalic astrocyte‐derived neurotrophic factor (MANF) is a secretory neurotrophic factor protein that promotes repair after neuronal injury. The microglia cell surface receptor (triggering receptor expressed on myeloid cells‐2; TREM2) regulates the production of pro‐ and antiinflammatory mediators after stroke. Here, we study MANF and TREM2 expression after middle cerebral artery occlusion (MCAo) and explore if docosahexaenoic acid (DHA) treatment exerts a potentiating effect.

Methods

We used 2 hours of the MCAo model in rats and intravenously administered DHA or vehicle at 3 hours after the onset of MCAo. Neurobehavioral assessment was performed on days 1, 3, 7, and 14; MANF and TREM2 expression was measured by immunohistochemistry and Western blotting.

Results

MANF was upregulated in neurons and astrocytes on days 1, 7, and 14, and TREM2 was expressed on macrophages in the ischemic penumbra and dentate gyrus (DG) on days 7 and 14. DHA improved neurobehavioral recovery, attenuated infarct size on days 7 and 14, increased MANF and decreased TREM2 expression in ischemic core, penumbra, DG, and enhanced neurogenesis on Day 14.

Conclusion

MANF and TREM2 protein abundance is robustly increased after MCAo, and DHA treatment potentiated MANF abundance, decreased TREM2 expression, improved neurobehavioral recovery, reduced infarction, and provided enhanced neuroprotection.

Psychoacoustics and neurophysiological auditory processing in patients with Charcot-Marie-Tooth disease types 1A and 2A

BACKGROUND AND PURPOSE

Hidden hearing loss has been reported in patients with Charcot-Marie-Tooth (CMT) disease; however, the auditory-processing deficits have not been widely explored. We investigated the psychoacoustic and neurophysiological aspects of auditory processing in patients with CMT disease type 1A (CMT1A) and type 2A (CMT2A).

METHODS

A total of 43 patients with CMT1A and 15 patients with CMT2A were prospectively enrolled. All patients with CMT disease had normal sound-detection ability by using pure-tone audiometry. Spectral-ripple discrimination, temporal modulation detection and auditory frequency-following response were compared between CMT1A, CMT2A and control groups.

RESULTS

Although all participants had normal audiograms, patients with CMT disease had difficulty understanding speech in noise. The psychoacoustic auditory processing was somewhat different depending on the underlying pathophysiology of CMT disease. Patients with CMT1A had degraded auditory temporal and spectral processing. Patients with CMT2A had no reduced spectral resolution, but they showed further reduced temporal resolution than the patients with CMT1A. The amplitudes of the frequency-following response were reduced in patients with CMT1A and CMT2A, but the neural timing remained relatively intact.

CONCLUSIONS

When we first assessed the neural representation to speech at the brainstem level, the grand average brainstem responses were reduced in both patients with CMT1A and CMT2A compared with healthy controls. As the psychoacoustic aspects of auditory dysfunctions in CMT1A and CMT2A were somewhat different, it is necessary to consider future auditory rehabilitation methods based on their pathophysiology.

Microthrombi Correlates With Infarction and Delayed Neurological Deficits After Subarachnoid Hemorrhage in Mice

BACKGROUND AND PURPOSE

Delayed neurological deficits are a devastating consequence of subarachnoid hemorrhage (SAH), which affects about 30% of surviving patients. Although a very serious concern, delayed deficits are understudied in experimental SAH models; it is not known whether rodents recapitulate the delayed clinical decline seen in SAH patients. We hypothesized that mice with SAH develop delayed functional deficits and that microthrombi and infarction correlate with delayed decline.

METHODS

Adult C57BL/6J mice of both sexes were subjected to endovascular perforation to induce SAH. Mice were allowed to survive for up to 1 week post-ictus and behavioral performance was assessed daily. Postmortem microthrombi, large artery diameters (to assess vasospasm), and infarct volume were measured. These measures were analyzed for differences between SAH mice that developed delayed deficits and SAH mice that did not get delayed deficits. Correlation analyses were performed to identify which measures correlated with delayed neurological deficits, sex, and infarction.

RESULTS

Twenty-three percent of males and 47% of females developed delayed deficits 3 to 6 days post-SAH. Female mice subjected to SAH had a significantly higher incidence of delayed deficits than male mice with SAH. Mice that developed delayed deficits had significantly more microthrombi and larger infarct volumes than SAH mice that did not get delayed deficits. Microthrombi positively correlated with infarct volume, and both microthrombi and infarction correlated with delayed functional deficits. Vasospasm did not correlate with either infarction delayed functional deficits.

CONCLUSIONS

We discovered that delayed functional deficits occur in mice following SAH. Sex differences were seen in the prevalence of delayed deficits. The mechanism by which microthrombi cause delayed deficits may be via formation of infarcts.

Surface waves control bacterial attachment and formation of biofilms in thin layers

Formation of bacterial biofilms on solid surfaces within a fluid starts when bacteria attach to the substrate. Understanding environmental factors affecting the attachment and the early stages of the biofilm development will help develop methods of controlling the biofilm growth. Here, we show that biofilm formation is strongly affected by the flows in thin layers of bacterial suspensions controlled by surface waves. Deterministic wave patterns promote the growth of patterned biofilms, while wave-driven turbulent motion discourages patterned attachment of bacteria. Strong biofilms form under the wave antinodes, while inactive bacteria and passive particles settle under nodal points. By controlling the wavelength, its amplitude, and horizontal mobility of the wave patterns, one can shape the biofilm and either enhance the growth or discourage the formation of the biofilm. The results suggest that the deterministic wave-driven transport channels, rather than hydrodynamic forces acting on microorganisms, determine the preferred location for the bacterial attachment.

Development of barium-based low viscosity contrast agents for micro CT vascular casting: Application to 3D visualization of the adult mouse cerebrovasculature

Recent advances in three-dimensional (3D) fluorescence microscopy offer the ability to image the entire vascular network in entire organs, or even whole animals. However, these imaging modalities rely on either endogenous fluorescent reporters or involved immunohistochemistry protocols, as well as optical clearing of the tissue and refractive index matching. Conversely, X-ray-based 3D imaging modalities, such as micro CT, can image non-transparent samples, at high resolution, without requiring complicated or expensive immunolabeling and clearing protocols, or fluorescent reporters. Here, we compared two "homemade" barium-based contrast agents to the field standard, lead-containing Microfil, for micro-computed tomography (micro CT) imaging of the adult mouse cerebrovasculature. The perfusion pressure required for uniform vessel filling was significantly lower with the barium-based contrast agents compared to the polymer-based Microfil. Accordingly, the barium agents showed no evidence of vascular distension or rupture, common problems associated with Microfil. Compellingly, perfusion of an aqueous BaCl₂ /gelatin mixture yielded equal or superior visualization of the cerebrovasculature by micro CT compared to Microfil. However, phosphate-containing buffers and fixatives were incompatible with BaCl₂ due to the formation of unwanted precipitates. X-ray attenuation of the vessels also decreased overtime, as the BaCl₂ appeared to gradually diffuse into surrounding tissues. A second, unique formulation composed of BaSO₄ microparticles, generated in-house by mixing BaCl₂ and MgSO₄ , suffered none of these drawbacks. These microparticles, however, were unable to pass small diameter capillary vessels, conveniently labeling only the arterial cerebrovasculature. In summary, we present an affordable, robust, low pressure, non-toxic, and straightforward methodology for 3D visualization of the cerebrovasculature.

Extracellular Vimentin/VWF (von Willebrand Factor) Interaction Contributes to VWF String Formation and Stroke Pathology

Background and Purpose- VWF (von Willebrand factor) strings mediate spontaneous platelet adhesion in the vascular lumen, which may lead to microthrombi formation and contribute to stroke pathology. However, the mechanism of VWF string attachment at the endothelial surface is unknown. We tested the novel hypothesis that VWF strings are tethered to the endothelial surface through an interaction between extracellular vimentin and the A2 domain of VWF. We further explored the translational value of blocking this interaction in a model of ischemic stroke. Methods- Human endothelial cells and pressurized cerebral arteries were stimulated with histamine to elicit VWF string formation. Recombinant proteins and antibodies were used to block VWF string formation. Mice underwent transient middle cerebral artery occlusion with reperfusion. Just before recanalization, mice were given either vehicle or A2 protein (recombinant VWF A2 domain) to disrupt the vimentin/VWF interaction. Laser speckle contrast imaging was used to monitor cortical perfusion. Results- Pressurized cerebral arteries produced VWF strings following histamine stimulation, which were reduced in arteries from Vim KO (vimentin knockout) mice. VWF string formation was significantly reduced in endothelial cells incubated with A2 protein or antivimentin antibodies. Lastly, A2 protein treatment significantly improved cortical reperfusion after middle cerebral artery occlusion. Conclusions- We provide the first direct evidence of cerebral VWF strings and demonstrate that extracellular vimentin significantly contributes to VWF string formation via A2 domain binding. Lastly, we show that pharmacologically targeting the vimentin/VWF interaction through the A2 domain can promote improved reperfusion after ischemic stroke. Together, these studies demonstrate the critical role of VWF strings in stroke pathology and offer new therapeutic targets for treatment of ischemic stroke.

Intraoperative Management to Prevent Cardiac Collapse in a Patient With a Recurrent, Large-volume Pericardial Effusion and Paroxysmal Atrial Fibrillation During Liver Transplantation: A Case Report

BACKGROUND

Pericardial effusion is a common feature of end-stage liver disease. In this case report we describe the intraoperative management of recurrent pericardial effusion, without re-pericardiocentesis, to prevent circulatory collapse during a critical surgical time-point; that is, during manipulation of the major vessels and graft reperfusion.

METHODS

A 47-year-old woman with hepatitis B was scheduled to undergo deceased donor liver transplantation (LT). A large pericardial effusion was preoperatively identified using transthoracic echocardiography (TTE). The patient also had paroxysmal atrial fibrillation. Two days before surgery, preemptive pericardiocentesis was performed and the 1150-mL effusion was drained. Intraoperatively, recurrence of the large pericardial effusion was identified using transesophageal echocardiography (TEE). During inferior vena cava manipulation, the surgeon consulted the anesthesiologist to evaluate the hemodynamic changes in the patient. After 3 attempts, the transplant team was able to determine the most appropriate anastomosis site, defined as that with the least impact on cardiac function. To prevent the development of severe postreperfusion syndrome, 10% MgSO₄ (2 g) was gradually infused 20 minutes before portal vein declamping, and immediately before graft reperfusion a 100-μg bolus of epinephrine was administered.

RESULTS

During graft reperfusion, there was no evidence of heart chamber collapse or flow disturbance, as seen on the TEE findings. Postoperatively, the patient recovered completely and was discharged from the hospital. Six months after surgery, there was no sign of pericardial effusion on follow-up TTE.

CONCLUSION

Our intraoperative strategy may prevent cardiac collapse in patients with pericardial effusion detected during LT. Intraoperative TEE plays an important role in guiding hemodynamic management.

How membrane lipids influence plasma delivery of reactive oxygen species into cells and subsequent DNA damage: an experimental and computational study

The combination of phospholipid vesicle experiments and molecular dynamics (MD) simulations illustrate how lipid oxidation, lipid packing and rafts formation may influence the response of healthy and diseased cell membranes to plasma-derived RONS.

Intraoperative Management of a Patient With Impaired Cardiac Function Undergoing Simultaneous ABO-Compatible Liver and ABO-Incompatible Kidney Transplant From 2 Living Donors: A Case Report

BACKGROUND

Combined liver and kidney transplant is a very complex surgery. To date, there has been no report on the intraoperative management of patients with impaired cardiac function undergoing simultaneous ABO-compatible liver and ABO-incompatible kidney transplant from 2 living donors.

CASE REPORT

A 60-year-old man underwent simultaneous ABO-compatible liver and ABO-incompatible kidney transplant from 2 living donors because of IgA nephropathy and alcoholic liver cirrhosis. The preoperative cardiac findings revealed continuous aggravation, shown by large left atrial enlargement, severe left ventricular hypertrophy, a very prolonged QT interval, and a calcified left anterior descending coronary artery. Severe hypotension with very weak pulsation and severe bradycardia developed, with an irregular junctional rhythm noted immediately after the liver graft was reperfused. Although epinephrine was administered as a rescue drug, hemodynamics did not improve, and central venous pressure and mean pulmonary arterial pressure increased to potentially fatal levels. Emergency phlebotomy via the central line was performed. Thereafter, hypotension and bradycardia recovered gradually as the central venous pressure and mean pulmonary arterial pressure decreased. The irregular junctional rhythm returned to a sinus rhythm, but the QTc interval was slightly more prolonged. Because of poor cardiac capacity, the volume and rate of fluid infusion were increased aggressively to maintain appropriate kidney graft perfusion after confirming vigorous urine production of the graft.

CONCLUSIONS

A heart with impaired function due to both end-stage liver and kidney diseases may be less able to withstand surgical stress. Further study on cardiac dysfunction will be helpful for the management of patients undergoing complex transplant surgery.

Canavalia ensiformis-derived lectin inhibits biofilm formation of enterohemorrhagic Escherichia coli and Listeria monocytogenes

AIM

A lectin Concanavalin A (ConA) derived from Canavalia ensiformis (jack bean) exhibits high-binding affinity to carbohydrates on bacterial cell surfaces. The objective of this study was to inhibit the biofilm formation of the foodborne pathogens enterohemorrhagic Escherichia coli and Listeria monocytogenes using ConA prepared by a membrane-based extraction method.

METHODS AND RESULTS

ConA was extracted using a simple and inexpensive membrane method instead of a chromatography approach. The extracted ConA was effective in inhibiting biofilms of E. coli by 30-fold and L. monocytogenes by 140-fold. In addition, ConA decreased the swimming motility of enterohemorrhagic E. coli EDL933 (EHEC) by 37%, resulting in low biofilm formation, as ConA binding to the bacterial cell surfaces might cause a reduced capability to adhere due to low cellular motility. We confirmed that the extracted ConA contains active components at less than 10 kDa as well as ConA multimers (>30 kDa) that repress EHEC biofilms. Additionally, noncell-based mannose reduced the activity of ConA in inhibiting biofilms.

CONCLUSIONS

ConA extracted using the membrane-based method is active in inhibiting the biofilm formation by E. coli and L. monocytogenes via the mannose-binding affinity of ConA.

SIGNIFICANCE AND IMPACT OF THE STUDY

ConA can be used as a promising anti-adherent and antibiofilm agent in inhibiting biofilm formation by enterohemorrhagic E. coli and L. monocytogenes. The membrane-based extraction approach may be applied for the economic production of biologically active lectins.

A homing system targets therapeutic T cells to brain cancer

Successful T cell immunotherapy for brain cancer requires that the T cells can access tumour tissues, but this has been difficult to achieve. Here we show that, in contrast to inflammatory brain diseases such as multiple sclerosis, where endothelial cells upregulate ICAM1 and VCAM1 to guide the extravasation of pro-inflammatory cells, cancer endothelium downregulates these molecules to evade immune recognition. By contrast, we found that cancer endothelium upregulates activated leukocyte cell adhesion molecule (ALCAM), which allowed us to overcome this immune-evasion mechanism by creating an ALCAM-restricted homing system (HS). We re-engineered the natural ligand of ALCAM, CD6, in a manner that triggers initial anchorage of T cells to ALCAM and conditionally mediates a secondary wave of adhesion by sensitizing T cells to low-level ICAM1 on the cancer endothelium, thereby creating the adhesion forces necessary to capture T cells from the bloodstream. Cytotoxic HS T cells robustly infiltrated brain cancers after intravenous injection and exhibited potent antitumour activity. We have therefore developed a molecule that targets the delivery of T cells to brain cancer.

Highly-Sensitive Refractive Index Sensing by Near-infrared Metatronic Nanocircuits

In this work, we present a highly-sensitive refractive index sensor based on metatronic nanocircuits operating at near-infrared spectral range. The structure is designed based on simple nanorod geometry and fabricated by nanopatterning of transparent conducting oxides. The functionality of these polarization dependent metatronic nanocircuits is enhanced by applying tunable response. This feature is investigated by depositing NH₂ (Amine) groups via plasma polymerization technique on top of indium-tin-oxide nanorods. The dielectric constant of Amine groups is a function of their thickness, which can be controlled by the RF power and the time duration of the applied plasma polymerization process. The resonance wavelengths of nanocircuits shift to higher wavelength, as the dielectric constant of the deposited material increases. An excellent agreement between the design and experimental results are obtained. Our metatronic based nanosensor offers a high-sensitive performance of 1587 nm/RIU with a satisfactory figure of merit for this class of sensors.

[A cohort study on body mass index and risk of all-cause mortality among hypertensive population]

Objective: To investigate the relationship between body mass index (BMI) and all-cause mortality in hypertensive population. Methods: All participants were selected from a prospective cohort study based on a rural population from Henan province, China. Cox proportional hazards regression models were used to estimate the associations of different levels of BMI stratification with all-cause mortality. Restricted cubic spline models were used to detect the dose-response relation. Results: Among the 5 461 hypertensive patients, a total of 31 048.38 person-years follow-up was conducted. The median of follow-up time was 6 years, and 589 deaths occurred during the follow-up period. Compared to normal weight group (18.5 kg/m(2)<BMI<24.0 kg/m(2)) the multivariate-adjusted hazard ratios for all-cause mortality associated with BMI levels (<18.5 kg/m(2), 24-28 kg/m(2), and ≥28 kg/m(2)) were 0.83 (95%CI: 0.37-1.87), 0.81 (95%CI: 0.67-0.97), and 0.72 (95%CI: 0.56-0.91), respectively. The dose-response analysis showed a nonlinear, reverse "S" shaped relationship (non-linearity P<0.001). Conclusion: Overweight or obese might have a protective effect on all-cause mortality in hypertensive population, which supports the "obesity paradox" phenomenon.

Abstract WP252: Mechanism of Secondary Thalamic Injury Induced by Focal Cortical Stroke

Remote secondary injury in the thalamus has been observed following rodent and human stroke and is associated with poorer recovery. However the mechanisms and resultant molecular changes whereby cortical infarction leads to remote injury in distant regions of brain are not well defined. The present studies utilize a mouse model of permanent distal MCAO (pdMCAO) with delayed secondary thalamic injury. We have measured time dependent molecular and cellular events, focusing on glial activation and neuronal death in the thalamus. These studies provide an important foundation for future studies aimed at reducing secondary brain injury.

Methods: Cortical infarction by pdMCAO was induced by microcauterization of the distal MCA in male C57BL/6J mice (11-13 wks). Cresyl violet (CV), fluoro-jade C (FJC) and immunochemical staining were performed at 24 hours, 3 days, 1 week, and 2 weeks after stroke (n=5, each time point) and in shams (n=3).

Results: First, we confirmed with TTC staining that the primary infarction induced by pdMCAO was restricted to the cortex of the MCA territory at 72 hours, and that no infarct was seen in the thalamus. Microglia and astrocyte activation (IBA-1 and GFAP, respectively) was first detectable in the ipsilateral ventral posteromedial nucleus (VPN) of the thalamus at 3 days after stroke, and progressively increased at 1 and 2 weeks. However, thalamic neuronal injury (by FJC staining) was not evident until 1 week after stroke. At 2 weeks following stroke, the number of FJC positive neurons further increased and significant morphological changes were evident by CV staining, including shrunken cytoplasm and condensed pyknotic nuclei.

Conclusions: We present a mouse stroke model for studying the mechanisms of secondary thalamic injury. In this model, primary cortical injury results in delayed cellular events in the ipsilateral thalamus, including an initial activation of microglia and astrocytes with subsequent neuronal injury and death. These studies provide necessary foundation for designing future interventional strategies aimed at reducing secondary injury following stroke.

Neuroprotectin D1 upregulates Iduna expression and provides protection in cellular uncompensated oxidative stress and in experimental ischemic stroke

Ring finger protein 146 (Iduna) facilitates DNA repair and protects against cell death induced by NMDA receptor-mediated glutamate excitotoxicity or by cerebral ischemia. Neuroprotectin D1 (NPD1), a docosahexaenoic acid (DHA)-derived lipid mediator, promotes cell survival under uncompensated oxidative stress (UOS). Our data demonstrate that NPD1 potently upregulates Iduna expression and provides remarkable cell protection against UOS. Iduna, which was increased by the lipid mediator, requires the presence of the poly(ADP-ribose) (PAR) sites. Moreover, astrocytes and neurons in the penumbra display an enhanced abundance of Iduna, followed by remarkable neurological protection when DHA, a precursor of NPD1, is systemically administered 1 h after 2 h of ischemic stroke. These findings provide a conceptual advancement for survival of neural cells undergoing challenges to homeostasis because a lipid mediator, made 'on demand,' modulates the abundance of a critically important protein for cell survival.

Ossicular chain reconstruction improves bone conduction threshold in chronic otitis media

This study aimed to assess the elevation of bone conduction threshold in patients with chronic otitis media and to investigate the mechanism of this phenomenon. One hundred and six patients with unilateral chronic otitis media who had undergone a tympanomastoidectomy were reviewed retrospectively. The differences in the bone conduction thresholds between the diseased and normal sides were assessed and compared according to the duration of the disease and the presence of cholesteatoma. Post-operative changes in the bone conduction threshold were also assessed. The mean bone conduction thresholds were significantly elevated on the diseased side, ranging from 3.4 to 11.6 dB across frequencies, with a maximal elevation at 2000 Hz. The duration of disease and the presence of cholesteatoma did not affect the degree of the bone conduction elevation. After ossicular reconstruction, bone conduction thresholds improved significantly at all frequencies, with the greatest improvement being observed at 2000 Hz. These results suggest that the elevation in the bone conduction threshold in chronic otitis media is mainly caused by a change in the conductive mechanism in the middle ear.

Abstract 146: Transient Receptor Potential Vanilloid 1 (TRPV1) Channel Contributes to Cerebral Reperfusion after Stroke

Introduction: The TRPV1 channel is a non-selective ion channel that is activated by capsaicinoids, temperature (>43 °C), and multiple factors produced during inflammation or injury. At this time, there is very little reported regarding a role of this channel in regulation of cerebral blood flow. Here we provide new evidence for TRPV1 in promoting microvascular reperfusion following stroke.

Hypothesis: Endothelial TRPV1 channels contribute to cerebral reperfusion following ischemic stroke.

Methods: Experiments were performed in male WT and TRPV1 knockout mice of C57BL/6 background. Immunofluorescence was performed in brain sections with TRPV1 and Pecam-1 antibodies. Pressurized artery preparations were performed with isolated superior cerebellar arteries. Relative cerebral blood flow measurements were performed by laser Doppler and laser speckle flowmetry in mice before, during, and after MCAO (20 or 30 min). Reperfusion was monitored continuously for 2-3 hours and again at 24 hours.

Results: TRPV1 expression was positively detected by immunofluorescence in the cerebral microvasculature, as assessed by Pecam-1 co-localization. TRPV1 KO mice were used as a negative control. Pressurized cerebral arteries demonstrated modest vasodilation to TRPV1 agonist (capsaicin) that was significantly potentiated with H 2 O 2 pre-treatment. The potentiated component of vasodilation was lost with removal of the endothelium, demonstrating the endothelial source of the response. Following brief MCA occlusion (20 or 30 min), WT mice demonstrated an initial return of cerebral perfusion followed by a transient drop in perfusion (~25% drop). This drop in perfusion started at 20-30 minutes into the reperfusion phase and lasted approximately one hour, at which point perfusion was restored to pre-stroke baseline value. In TRPV1 KO mice, the drop in perfusion was more profound (~65% drop) and persisted through 3 hours. By 24 hours, flow was restored to baseline in both groups.

Conclusions: These data demonstrate a functional role for TRPV1 channels during reperfusion. We speculate that endothelial TRPV1 channels are functionally potentiated during injury and contribute to the vasodilatory capacity of the cerebral microvasculature following stroke.

Abstract WMP83: Extracellular Vimentin Contributes to Von Willebrand Factor (VWF) String Formation in the Cerebrovasculature Following Endothelial Activation

Introduction: VWF strings can form within the vascular lumen following endothelial activation and have been implicated in platelet adhesion and worsened outcome following stroke. However, the molecular interactions facilitating VWF string anchorage to the endothelial surface are currently unknown. Here we examined the novel role of endothelial vimentin in mediating the anchorage of VWF strings within the cerebrovasculature. We hypothesize that VWF released from activated endothelium remains anchored at the luminal surface (i.e. VWF strings) through direct interaction with extracellular vimentin.

Methods: Cultured endothelial cell (EC) experiments were performed with human umbilical vein EC (HUVECs) and human brain microvascular EC (HBMVECs). EC were stimulated with histamine (10 uM) under flow conditions. Specific protein interactions were probed with recombinant vimentin and A2 domain of VWF. Mouse middle cerebral and superior cerebellar arteries from WT and vimentin KO mice were set up in a pressurized artery chamber, stimulated with histamine, and then processed for VWF immunofluorescence to quantify VWF strings. VWF string formation was further evaluated by cranial window preparation using labeled platelets to detect real-time in vivo string formation.

Results: In cultured EC, histamine stimulation promoted the production of long VWF strings that were significantly attenuated in the presence of recombinant vimentin or A2 domain of VWF. In pressurized cerebral arteries, histamine stimulation promoted VWF strings that aligned along the luminal endothelial surface. VWF string formation was reduced 2.9 fold in arteries from vimentin knockout mice (P=0.02). Histamine stimulation in the cranial window produced platelet-adherent strings in the pial microvasculature.

Conclusions: These studies provide in vitro and in vivo evidence for a novel interaction between vimentin and the A2 domain of VWF at the endothelial surface which contributes to the anchorage of VWF strings in the microvasculature. This vimentin/VWF interaction critically regulates VWF-mediated platelet adhesion at the surface of activated endothelium and could thus provide a novel therapeutic target in the treatment of acute ischemic stroke.

Abstract TP268: Induction Profile of Mesencephalic Astrocyte-derived Neurotrophic Factor by Cerebral Ischemia and its Implication for Neuroprotection

Introduction: Mesencephalic astrocyte-derived neurotrophic factor (MANF) has been identified as a secretion protein, which biases immune cells toward an anti-inflammatory phenotype, thereby promoting tissue repair after various injuries to neurons in vivo or in vitro. However, the function of MANF during and after brain ischemia is still not known. The purpose of our study was to examine the characteristics and implication of MANF expression induced by focal cerebral ischemia. In addition we investigated if docosahexaenoic acid (DHA) potentiates MANF mRNA expression and provides additional neuroprotection.

Methods: Male SD (280-320) rats were anesthetized with isoflurane and subjected to 2 h of middle cerebral artery occlusion (MCAo) by intraluminal suture. DHA (5 mg/kg; n=13) or vehicle (saline; n=8) was administered IV at 3 h after the onset of MCAo. Neurological function was evaluated during occlusion (60 min) and on days 1, 3 and 7 after MCAo. MANF mRNA expression, protein levels, and apoptosis were measured by immunohistochemistry and Western blotting.

Results: Behavioral deficit was significantly improved by treatment with DHA compared to vehicle on days 1, 3 and 7. MANF was found to be extremely upregulated in the ischemic penumbra. The expression of MANF was neuronal in the cortex and dentate gyrus. DHA administration significantly increased the number of MANF + /NeuN + cells in the cortex (by 76.6 %) and dentate gyrus (by 20.5 %) compared to saline-treated animals. The number of MANF/NeuN-positive cells was not different in the subcortex, CA1 and CA3 regions between DHA- and saline-treated groups. Treatment with DHA increased MANF + /GFAP + cells in the subcortex (by 27.7 %) and dentate gyrus (by 38.0 %) compared to the vehicle-treated brains. Total and cortical infarct volumes were attenuated by DHA treatment by 48 % and by 73 % compared to vehicle treatment at 24 h after MCAo.

Conclusion: MANF mRNA expression and protein levels are increased after focal cerebral ischemia. It was found to be extremely upregulated in the ischemic penumbra and dentate gyrus. The expression of MANF was mostly neuronal and astrocytic. DHA potentiates MANF expression and provides additional neuroprotection.

Abstract WP118: Docosahexaenoic Acid Provides Neuroprotection by Increasing Neurogenesis After Experimental Stroke

Introduction: Ischemic injury induces neurogenesis in the subventricular zone (SVZ) of the lateral ventricles and subgranular zone (SGZ) of dentate gyrus (DG), and it promotes the migration of neuroblasts, guided by blood vessels, into the ischemic damaged area. Recently, we have shown that docosahexaenoic acid (DHA; 22:6n-3) therapy improves functional and histological outcomes following experimental stroke. The objective, hence, is to determine whether DHA administration enhances endogenous neurogenesis after cerebral ischemia.

Methods: Twenty-one male SD rats were anesthetized with isoflurane and subjected to 2 h of middle cerebral artery occlusion (MCAo) by intraluminal filament. DHA (5 mg/kg, n=10) or saline (n=11) was administered intravenously at 3 h after onset of MCAo (n = 7-10 per group). BrdU was injected on days 4, 5 and 6. DCX (doublecortin), NeuN (a marker for mature neurons), ki-67 (marker for cell proliferation) have been used to test the proliferation, migration and differentiation of neural precursor cells. Behavioral tests were conducted on days 1, 2 and 3 and weeks 1 and 2. Immunohistochemistry with BrdU and ki-67, DCX or NeuN, and histopathology were performed on day 14.

Results: DHA-treated animals showed improved neurologic scores compared to the saline group during the two-week survival period. Total, cortical and subcortical infarct areas in the DHA-treated group were significantly attenuated at multiple bregma levels as well as total, cortical and subcortical infarct volumes by 42.4 %, by 47.5 %, and by 31.2 % compared to the vehicle-treated group. The number of BrdU + /ki-67 + cells in DHA-treated rats was increased in cortex by 88 %, SVZ by 40 % and DG by 270 % compared to saline-treated rats. DHA treatment increased the number of BrdU + /DCX + cells in the cortex by 65 %, the SVZ by 29 % and the DG (by 58 %) compared to saline-treated group. In addition, the numbers of BrdU + /NeuN + cells were increased in the cortex by 49 %, SVZ by 28 % and DG by 48% compared to vehicle treatment.

Conclusion: DHA increased neurogenesis by proliferation, differentiation and migration of neural stem cells in the DG, SVZ and peri-infarct area two weeks after ischemic stroke. In addition, DHA promoted neurobehavioral recovery and reduced infarct volume.

Deformation mechanisms to ameliorate the mechanical properties of novel TRIP/TWIP Co-Cr-Mo-(Cu) ultrafine eutectic alloys

In the present study, the microstructural evolution and the modulation of the mechanical properties have been investigated for a Co-Cr-Mo (CCM) ternary eutectic alloy by addition of a small amount of copper (0.5 and 1 at.%). The microstructural observations reveal a distinct dissimilarity in the eutectic structure such as a broken lamellar structure and a well-aligned lamellar structure and an increasing volume fraction of Co lamellae as increasing amount of copper addition. This microstructural evolution leads to improved plasticity from 1% to 10% without the typical tradeoff between the overall strength and compressive plasticity. Moreover, investigation of the fractured samples indicates that the CCMCu alloy exhibits higher plastic deformability and combinatorial mechanisms for improved plastic behavior. The improved plasticity of CCMCu alloys originates from several deformation mechanisms; i) slip, ii) deformation twinning, iii) strain-induced transformation and iv) shear banding. These results reveal that the mechanical properties of eutectic alloys in the Co-Cr-Mo system can be ameliorated by micro-alloying such as Cu addition.

Clinical Trial of Osteochondral Lesion of Talus Treated with Human Mesenchymal Stem Cell

Category:

Ankle.

Introduction/Purpose:

The aim of surgery for osteochondral lesion of talus is to restore the damaged articular surface with a nearly normal cartilage and supporting subchondral bone. The operative treatment paradigms are still controversial. Though arthroscopic bone-marrow stimulation, autologous osteochondral transplantion and chondrocyte implantation have been performed, but the limitations of these techniques necessitate innovative methods such as cell-based treatment. We investigated the safety and efficacy of human umbilical cord-blood derived mesenchymal stem cell product (CartistemTM) in the treatment of symptomatic osteochondral lesion of the talus.

Methods:

Between Feb 2014 and March 2015, 25 symptomatic OLT patiens were enrolled and randomized into 2 groups with informed consents. They have all suffered from ankle pain more than 6 months despite of conservative treatment. The control group(12 patients) underwent the standard arthroscopic curettage and microfracture, and the study group(13 patients) had additional application of Cartistem on the defect after the same procedure. We measured and analyzed AOFAS ankle-hindfoot scale and MRI features of T2mapping, dGEMRIC, and MOCART scale as well as arthroscopic gross finding with ICRS(international cartilage repair society) scale at 48th week after the index surgery. Also any adverse reactions or complications were recorded. We acquired IRB approval and registered this study at clinicalTrial.gov as NCT02338375.

Results:

There was no adverse effect or complication related to procedures and test drug. Clinically AOFAS ankle-hindfoot score was improved significantly after surgery in both groups, but there was no difference between them. Radiologically both groups showed significant improvement of MRI features without any differences. However on second look arthroscopic exam there was a tendency of better regenerative pattern(ICRS gross finding) in study group.

Conclusion:

There was no adverse reaction and additional benefit of human mesenchymal stem cell product in treatment of symptomatic OLT. However in terms of arthroscopic findings, it might help better histologic regeneration. Further investigation with longer term follow-up can guarantee its usefulness in treatment of OLT.

Correlation Between the Talar Tilt Angle and Hindfoot Varus in Medial Ankle OA

Category:

Ankle Arthritis

Introduction/Purpose:

Radiographically medial ankle osteoarthritis shows different features according to talar tilt which is known to an important determining factor in low tibial osteotomy surgery. However, little is known about the reason of this presentation. We hypothesized that the talar tilt angle and degree of hind foot varus might be correlated.

Methods:

We reviewed radiographs of 184 patients diagnosed with medial ankle osteoarthritis between May 2006 and February 2015. A total of 126 ankles in 97 patients diagnosed as Takakura stage 1–3b medial ankle osteoarthritis, were reviewed. We measured tibio-talar angle, talar tilt angle, tibial-anterior surface angle, and hindfoot alignment angle We divided the ankles into 4 groups according to tibio-talar angle by 10 degrees, and each group was further divided into 2 subgroups based on median talar tilt angle. We analyzed the correlation between talar tilt and hindfoot alignment angle in each group. We analyzed the differences in the hind foot alignment between the subgroups. Ankle radiographs of selected patients were measured by two observers to determine the interobserver reliability. One of the observers evaluated all radiographs twice to determine the intraobserver reliability.

Results:

The tibiotalar angle was strongly correlated with the talar tilt angle (r=−0.845), while there was no correlation between tibio-talar angle and hindfoot alignment angle(r=-0.595). Among the groups, tibio-talar angle of 70-80 showed a significantly different hindfoot alignment between the 2 subgroups (p=0.0187). In the rest groups, there was no significant difference between tibio-talar and hindfoot alignment angle. The interobserver and intraobserver reliability for all radiographic measurements was good to excellent

Conclusion:

We could find out a definite correlation between talar tilt and hindfoot alignment angle in certain degree of varus ankle OA, and no correlation between tibio-talar angle and hindfoot alignment, which might have a clincal relevance in determining the method of osteotomy surgery.

Hexa (ethylene glycol) derivative of benzothiazole aniline promotes dendritic spine formation through the RasGRF1-Ras dependent pathway

Our recent study demonstrated that an amyloid-β binding molecule, BTA-EG4, increases dendritic spine number via Ras-mediated signaling. To potentially optimize the potency of the BTA compounds, we synthesized and evaluated an amyloid-β binding analog of BTA-EG4 with increased solubility in aqueous solution, BTA-EG6. We initially examined the effects of BTA-EG6 on dendritic spine formation and found that BTA-EG6-treated primary hippocampal neurons had significantly increased dendritic spine number compared to control treatment. In addition, BTA-EG6 significantly increased the surface level of AMPA receptors. Upon investigation into the molecular mechanism by which BTA-EG6 promotes dendritic spine formation, we found that BTA-EG6 may exert its effects on spinogenesis via RasGRF1-ERK signaling, with potential involvement of other spinogenesis-related proteins such as Cdc42 and CDK5. Taken together, our data suggest that BTA-EG6 boosts spine and synapse number, which may have a beneficial effect of enhancing neuronal and synaptic function in the normal healthy brain.

Hepatic differentiation of porcine embryonic stem cells for translational research of hepatocyte transplantation

Porcine embryonic stem cells (ES) are considered attractive preclinical research tools for human liver diseases. Although several studies previously reported generation of porcine ES, none of these studies has described hepatic differentiation from porcine ES. The aim of this study was to generate hepatocytes from porcine ES and analyze their characteristics. We optimized conditions for definitive endoderm induction and developed a 4-step hepatic differentiation protocol. A brief serum-free condition with activin A efficiently induced definitive endoderm differentiation from porcine ES. The porcine ES-derived hepatocyte-like cells highly expressed hepatic markers including albumin and α-fetoprotein, and displayed liver characteristics such as glycogen storage, lipid production, and low-density lipoprotein uptake. For the first time, we describe a highly efficient protocol for hepatic differentiation from porcine ES. Our findings provide valuable information for translational liver research using porcine models, including hepatic regeneration and transplant studies, drug screening, and toxicology.

Tumour volume changes assessed with high-quality KVCT in lung cancer patients undergoing concurrent chemoradiotherapy

OBJECTIVE

We evaluated tumour volume changes in patients with lung cancer undergoing concurrent chemoradiotherapy using image-guided radiotherapy (RT).

METHODS

The kilovoltage image was obtained using CT on rail at every five fractions. The gross tumour volumes (GTVs), including the primary tumour and lymph nodes (LNs), were contoured to analyse the time and degree of tumour regression.

RESULTS

46 patients [32, non-small-cell lung cancer (NSCLC), and 14, small-cell lung cancer (SCLC)] were included in this study. In total, 281 CT scans and 82 sites of GTVs were evaluated. Significant volume changes occurred in both the NSCLC and SCLC groups (p < 0.001 and 0.002), and the average GTV change compared with baseline was 49.85 ± 3.65 [standard error (SE)]% and 65.95 ± 4.60 (SE)% for the NSCLC and SCLC groups, respectively. A significant difference in the degree of volume reduction between the primary tumour and LNs was observed in only the NSCLC group (p < 0.0001) but not in the SCLC group (p = 0.735). The greatest volume regression compared with the volume before the five fractions occurred between the 15 and 20 fractions in the NSCLC group and between the 5 and 10 fractions in the SCLC group.

CONCLUSION

Both primary tumour and LNs were well defined using CT on rail. Significant volume changes occurred during RT, and there was a difference in volume reduction between the NSCLC and SCLC groups, regarding the degree and timing of the tumour reduction in the primary tumour and LNs.

ADVANCES IN KNOWLEDGE

NSCLC and SCLC groups showed differences in the degree and timing of volume reduction. The primary tumour and LNs in NSCLC regressed differently.

The MRI appearances of cancellous allograft bone chips after the excision of bone tumours

Cancellous allograft bone chips are commonly used in the reconstruction of defects in bone after removal of benign tumours. We investigated the MRI features of grafted bone chips and their change over time, and compared them with those with recurrent tumour. We retrospectively reviewed 66 post-operative MRIs from 34 patients who had undergone curettage and grafting with cancellous bone chips to fill the defect after excision of a tumour. All grafts showed consistent features at least six months after grafting: homogeneous intermediate or low signal intensities with or without scattered hyperintense foci (speckled hyperintensities) on T1 images; high signal intensities with scattered hypointense foci (speckled hypointensities) on T2 images, and peripheral rim enhancement with or without central heterogeneous enhancements on enhanced images. Incorporation of the graft occurred from the periphery to the centre, and was completed within three years. Recurrent lesions consistently showed the same signal intensities as those of pre-operative MRIs of the primary lesions. There were four misdiagnoses, three of which were chondroid tumours. We identified typical MRI features and clarified the incorporation process of grafted cancellous allograft bone chips. The most important characteristics of recurrent tumours were that they showed the same signal intensities as the primary tumours. It might sometimes be difficult to differentiate grafted cancellous allograft bone chips from a recurrent chondroid tumour.

Abstract W P254: Docosahexaenoic Acid Therapy of Experimental Hemorrhagic Stroke

INTRODUCTION: Recently we have shown that novel therapy with docosahexaenoic acid (DHA) and DHA complexed to albumin (DHA-Alb) is neuroprotective after ischemic stroke in rats. The purpose of this study was to determine whether treatment with DHA and DHA-Alb would protect against intracerebral hemorrhagic stroke (ICH).

METHODS: The ICH model was produced in male Sprague-Dawley rats by a double-injection method in which 45 μl of fresh arterial blood was injected into the right striatum. The neurological status was evaluated after ICH (at 50 min) and at 1h, 1, 2, 3 and 7 days after treatment; a grading scale of 0-12 was employed (normal score=0, maximal deficit=12). Six groups we studied: DHA (5 mg/kg), Alb (0.63 or 1.25 g/kg), DHA-Alb (5 mg/kg+0.63 g/kg or 5 mg/kg+1.25 g/kg) or saline were administered i.v. at 60 min after ICH (n=10-12 per group). Ex vivo imaging of the brains was conducted on 11.7T MRI on day 7. High-resolution T2 weighted images (T2WI) and apparent diffusion coefficient maps were generated. After completion of the MRI study, histopathology and immunochemistry were conducted and hematoma volumes were determined.

RESULTS: The physiological variables were entirely comparable among the six groups. Treatment with DHA significantly improved behavior on days 1, 2, 3 and 7 (by 25-32) and reduced hematoma volume by a mean of 33% compared to saline group. Animals treated with low and moderate doses of DHA-Alb showed an improved neurological score compared to corresponding Alb groups on day 1 (23 and 26%), day 2 (32 and 31%), day 3 (34 and 33%) and day 7 (31 and 36%, respectively). MRI revealed a consistent hematoma involving the striatum and overlying corpus callosum. Moderate doses of DHA-Alb reduced hematoma volumes compared to Alb group (by 42%). Low dose of DHA-Alb also reduced hematoma volumes, but it was not statistically different from Alb group. Lesion volumes computed from T2WI images and by histopathology agreed closely with one another and were highly correlated.

CONCLUSION: We concluded that both, DHA and DHA-Alb therapy provides neurobehavioral recovery and reduces hematoma volume when administered at 1h after ICH in rats.