Faculty Bibliography

OBJECTIVE: Rotator cuff tendon tears are the most common soft tissue injuries in the shoulder joint. Various animal models have been described for this condition, but all current translational animal models have inherent weaknesses in their ability to generate chronically degenerated rotator cuff tendons. The objective of this study was to evaluate a partial infraspinatus tendon transection model as a means of creating a chronically degenerated rotator cuff tendon in an ovine model and compare the injury characteristics of this model to those observed in human patients with severe chronic rotator cuff tendon injuries. STUDY DESIGN/METHODS: The infraspinatus tendons of six sheep were partially detached followed by capping of the detached medial section of the tendon with Gore-Tex. Human tissue samples of the supraspinatus tendon were harvested from patients undergoing primary reverse shoulder arthroplasty and served as positive controls of chronic rotator cuff tendinopathy. RESULTS: Transected sheep tendons were characterized predominantly by an acute reactive and reparative pathological process as compared with the chronic degenerative changes observed in the human tendons. In contrast, the non-transected portion of the ovine tendon showed histological changes, which were more chronic and degenerative in nature when compared with the transected tendon. CONCLUSION/CONCLUSIONS: Overall, histological features of the non-transected portion of ovine tendon were more similar to those observed in the chronic degenerated human tendon.

Background and aims: Inadequate norepinephrine (NE) release in neurogenic orthostatic hypotension (nOH) causes fall in standing blood pressure. Ampreloxetine, a novel, long-acting NE reuptake inhibitor may improve symptoms of nOH. The objective of this study was to explore durability of effect and safety of once-daily oral ampreloxetine for symptomatic treatment of nOH.
Method(s): In an open-label, phase 2, exploratory study, subjects received ampreloxetine (3-20mg) once-daily for up to 20 weeks, with 4-week follow-up after ampreloxetine withdrawal and restarting alternative pressor agents. Assessments included Orthostatic Hypotension Symptom Assessment Item 1 (OHSA#1; dizziness, lightheadedness, feeling faint), OHSA/Orthostatic Hypotension Daily Activities Scale (OHDAS) composite scores, and change in Patient Global Impression of Severity (PGI-S).
Result(s): Seventeen symptomatic subjects (baseline OHSA#1 score >4) were enrolled (mean age, 65 years). At Weeks 4 and 20, mean (SD) improvement on OHSA#1 was -3.8 (3.1) and -3.1 (3.0) point, and ~77% and ~86% of subjects reported >=1-point improvement, respectively. Improvement, seen as early as Week 1, was sustained throughout the study. Deterioration to baseline severity was observed after ampreloxetine withdrawal. Similar trends were seen in OHSA/OHDAS composite scores, and change in PGI-S. Most common adverse events (AEs) were urinary tract infection (24%), hypertension (19%) and headache (14%), with no study-drug-related serious AEs. Ampreloxetine showed durable symptom improvement over 20 weeks, with return to baseline severity after ampreloxetine withdrawal. Ampreloxetine was well tolerated.
Conclusion(s): These encouraging findings of durable symptom improvement with open-label ampreloxetine treatment are being evaluated in ongoing Phase 3, doubleblind, confirmatory studies in subjects with nOH

Background/UNASSIGNED:Although the COVID-19 pandemic is affecting a relatively small proportion of the global population, its effects have already reached everyone. The pandemic has the potential to differentially disadvantage chronically ill patients, including those with Parkinson's disease (PD). The first health care reaction has been to limit access to clinics and neurology wards to preserve fragile patients with PD from being infected. In some regions, the shortage of medical staff has also forced movement disorders neurologists to provide care for patients with COVID-19. Objective/UNASSIGNED:To share the experience of various movement disorder neurologists operating in different world regions and provide a common approach to patients with PD, with a focus on those already on advanced therapies, which may serve as guidance in the current pandemic and for emergency situations that we may face in the future. Conclusion/UNASSIGNED:Most of us were unprepared to deal with this condition given that in many health care systems, telemedicine has been only marginally available or only limited to email or telephone contacts. In addition, to ensure sufficient access to intensive care unit beds, most elective procedures (including deep brain stimulation or the initiation of infusion therapies) have been postponed. We all hope there will soon be a time when we will return to more regular hospital schedules. However, we should consider this crisis as an opportunity to change our approach and encourage our hospitals and health care systems to facilitate the remote management of chronic neurological patients, including those with advanced PD.

Neck pain and headache are two of the most common complications of whiplash injury. Therefore, we performed a systematic literature search on PubMed and Embase for publications reporting on the prevalence of neck pain and headache following whiplash injury. The literature search identified 2,709 citations of which 44 contained relevant original data. Of these, 27 studies provided data for the quantitative analysis. For non-population-based studies, the present meta-analysis showed that a pooled relative frequency of neck pain was 84% CI (68-95%) and a pooled relative frequency of headache was 60% (46-73%), within 7 days following whiplash injury. At 12 months post-injury, 38% (32-45%) of patients with whiplash still experienced neck pain, while 38% (18-60%) of whiplash patients reported headache at the same time interval post-injury. However, we also found considerable heterogeneity among studies with I-values ranging from 89-98% for the aforementioned meta-analyses. We believe that the considerable heterogeneity among studies underscores the need for clear-cut definitions of whiplash injury and standardized reporting guidelines for post-whiplash sequelae such as neck pain and headache. Future studies should seek to optimize these aspects paving the way for a better understanding of the clinical characteristics and natural course of whiplash-associated sequelae.

Non-steroidal anti-inflammatory drugs (NSAIDs), commonly known as COX-1/COX-2 inhibitors, can be effective in treating mild to moderate migraine headache. However, the mechanism by which these drugs act in migraine is not known, nor is the specific contribution of COX-1 versus COX-2 known. We sought to investigate these unknowns using celecoxib, which selectively inhibits the enzymatic activity of COX-2, by determining its effects on several migraine-associated vascular and inflammatory events. Using in vivo two-photon microscopy, we determined intraperitoneal celecoxib effects on CSD-induced blood vessel responses, plasma protein extravasation, and immune cell activation in the dura and pia of mice and rats. Compared to vehicle (control group), celecoxib reduced significantly CSD-induced dilatation of dural arteries and activation of dural and pial macrophages but not dilatation or constriction of pial arteries and veins, or the occurrence of plasma protein extravasation. Collectively, these findings suggest that a mechanism by which celecoxib-mediated COX-2 inhibition might ease the intensity of migraine headache and potentially terminate an attack is by attenuating dural macrophages activation and arterial dilatation outside the blood brain barrier (BBB), and pial macrophages activation inside the BBB.

Huntington disease, a neurodegenerative disease characterized by progressive motor, behavioral, and cognitive decline, is caused by a CAG trinucleotide repeat expansion in the huntingtin gene on chromosome 4. Current treatments target symptom management because there are no disease-modifying therapies at this time. Investigation of RNA-based and DNA-based treatment strategies are emerging and hold promise of possible future disease-modifying therapy.

BACKGROUND AND PURPOSE/OBJECTIVE:Mechanical circulatory support (MCS) devices are commonly used in heart failure patients. These devices carry risk for presumably embolic and additionally hemorrhagic stroke. Alterations in blood flow play a key role in stroke pathophysiology, and we aimed to learn more about hemodynamic compromise. In this study, we used transcranial Doppler (TCD) ultrasound to define hemodynamics of commonly used nonpulsatile MCS devices, as well as pulsatile devices, with special attention to the total artificial heart (TAH). METHODS:From 2/2013 through 12/2016, we prospectively enrolled patients with MCS who underwent TCD imaging. We analyzed TCD parameters, including peak systolic velocity, end-diastolic velocity, pulsatility indices (PIs), and number of high-intensity transient signals. Waveform morphologies were compared between various MCS devices. RESULTS:We performed 132 TCD studies in 86 MCS patients. Waveforms in patients supported by venoarterial-extracorporeal membrane oxygenation demonstrated continuous flow without clear systolic peaks with an average (±SD) PI of .43 (±.2). PIs were low in patients with continuous-flow left ventricular assist devices with a mean PI of .32 (±.13). Impella patients had morphologically distinct pulsatile waveforms and a higher mean PI of .65 (±.24). In intra-arterial balloon pump patients, mean PI was 1.01 (±.16) and diastolic upstrokes were pronounced. In TAH patients, mean middle cerebral artery velocity of 79.69 (±32.33) cm/seconds and PI of .74 (±.14) approached normal values. CONCLUSION/CONCLUSIONS:TCD can detect characteristic waveforms in patients supported by various MCS devices. These device-specific TCD patterns are recognizable and reproducible.

Objectives: Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disorder that is characterized by selective degeneration of both upper and lower motor neurons, resulting in paralysis of skeletal muscle and respiratory failure, with death occurring within 2-5 years of diagnosis. 90% of cases are sporadic, and of the 10% that are familial more than 20 genes (>150 mutations) have been found to be associated with ALS, most notably copper/zinc superoxide dismutase (SOD1). SOD1 mutant proteins are believed to cause toxicities in degenerating neurons. Studies suggest that the neuronal and non-neuronal cell contributions to the onset and progression of ALS are complex. It was proposed that there are two phases of neuroinflammation in the spinal cord - the first being an early neuroprotective phase followed by a second late neurotoxic phase. One of the challenges in the study of neuroinflammation is that it is difficult to serially track the disease process, as there are no bona fide biomarkers for onset and progression in ALS. For this reason, we use PET with [¹¹C]PBR28 to track microglial neuroinflammation in the brain and spinal cord. We and others have shown that the receptor for advanced glycation end products (RAGE) is highly expressed in human ALS spinal cord, particularly in microglia, and to an increased degree compared to that of age-matched control subjects. Our previous studies with myeloid/microglia deletion of Ager and treatment with sRAGE (soluble RAGE) suggested that RAGE impairs survival and motor function in Sod1G93Amice. The ultimate goal is to test the hypothesis that RAGE inhibition in either initiation or progression phases of the ALS will prolong survival and maintain motor function in adult Sod1G93Amice.
Method(s): MicroPET/CT (Inveon, Siemens) with [¹¹C]PBR28 was used to track and compare microglial neuroinflammation in the brain and spinal cord of WT vs. ALS mice (110-120 day old), also after treatment with RAGE inhibitors (subject identity was blind to study investigator and data analyst). Using IRW (Inveon Research Workplace, Siemens), several ROIs in the thoracic and lumbar spinal cord (T13, L1, L2, L3) were drawn on the fused PET/CT images to obtain the regional SUVs. An automated atlasbased methodology using Firevoxel (https://urldefense.proofpoint.com/v2/url?u=https-3A__wp.nyu.edu_Firevoxel&d=DwIBAg&c=j5oPpO0eBH1iio48DtsedeElZfc04rx3ExJHeIIZuCs&r=CY_mkeBghQnUPnp2mckgsNSbUXISJaiBQUhM-Uz9W58&m=_uGsTvUTTD_GxqvwK245ZUiiSbzVraIboytFijFDOwU&s=RlC-AQtmqr84rzBwvDmgK_FCVdvbCfsFvuN-dVODTpM&e= ) that we previously developed was used for brain mapping and segmentation to derive regional timeactivity curves (TAC) and SUVs for 20 brain regions.
Result(s): Dynamic regional SUV [¹¹C]PBR28 binding data were obtained and averaged SUVs derived from the last 5 frames (with steady and less variable intensity levels) were compared. Results derived from both spinal cord and brain regions displayed a similar trend with two obvious clusters. Reduced binding was observed for ALS group as compared to WT. RAGE inhibitor-treated ALS mi ce showed increased binding (brain SUV avg. 0.402+/-0.0382 over 20 ROIs) as compared to vehicle-treated (0.157+/-0.0339), suggesting that RAGE inhibition may contribute to the restoration of homeostasis in ALS animals (i.e., their bindings after treatment were closer to those in WT (0.485+/-0.171)). Notably, hypothalamus, brain stem, and olfactory bulb consistently exhibited higher binding, suggesting their role in this regulation.
Conclusion(s): Inconsistent outcomes have been reported in the literature when comparing TSPO ligand binding for imaging neuroinflammation. Our data are consistent with findings from several recent studies; i.e., reduced PBR28 binding was associated with disease state (e.g., in patients with PTSD or alcoholism). A notion that the reduced binding might reflect competition from endogenous TSPO ligands such as cholesterol can't be excluded. The strategies described here will test the hypothesis that pharmacological antagonism of RAGE signal transduction in either initiation or progression phases of the ALS will prolong survival and maintain motor function in adult Sod1G93Amice