Citations

Abstract Background Spinal cord stimulation (SCS) is a highly effective therapy for treatment of chronic pain, however due to the complexity of pain, measuring a subject’s long-term response to the therapy remains difficult. Frequent measurement of patient-reported outcomes (PROs) to reflect multiple aspects of subjects’ pain is a crucial step in determining therapy outcomes. However, collecting full-length PROs is burdensome for both patients and clinicians. The objective of this work is to investigate the feasibility of using limited sets of outcomes from multiple PROs to accurately characterize subjects’ response to SCS therapy. Methods Validated PROs were used to capture pain, physical function and disability, as well as psychometric, satisfaction, and global health metrics. PROs were collected from 509 patients implanted with a neurostimulator enrolled in the post-market REALITY study. Combination of Pearson’s correlation and factor analysis was used to eliminate highly correlated questions and find the minimal meaningful set of questions within the predefined domains of each scale. Results The shortened versions of the questionnaires presented almost identical accuracy for classifying SCS therapy outcome as compared to the validated full-length versions. In addition, principal component analysis was performed on all the PROs and showed a robust clustering of pain intensity, psychological factors, physical function, and sleep across multiple PROs. A selected set of questions captured from multiple PROs can provide adequate information for measuring SCS therapy outcomes. Conclusions These shorter and more targeted PROs could result in better patient engagement, enhanced and more frequent data collection processes for digital health platforms, and ultimately increased patient satisfaction with SCS therapy. Trial registration Data for our analysis were extracted from the ongoing prospective, multicenter, international REALITY (Long-Term Real-World Outcomes Study on Patients Implanted with a Neurostimulator) study (NCT03876054).

Abstract Macrophage migration inhibitory factor (MIF1) is a pleiotropic cytokine involved in inflammation and cancer. Genetic knockout of Mif1 in the validated N ‐butyl‐ N ‐(4‐hydroxybutyl) nitrosamine (BBN) model of bladder cancer (BCa) resulted in stage arrest at non‐muscle‐invasive disease in prior studies. Small‐molecule inhibition of MIF1 reduced cancer‐associated outcomes, but it did not fully recapitulate genetic models. D‐dopachrome tautomerase (gene symbol DDT ), commonly referred to as MIF2, is a functional homolog of MIF1, and both MIF1 and MIF2 can bind the cell surface receptor CD74 on multiple cell types to initiate a signaling cascade. It has been proposed that this interaction mediates part of the protumorigenic effects of MIF1 and MIF2 and may explain the discordance in prior studies. We hypothesized that MIF2 functions redundantly with MIF1 in BCa development and progression. The Cancer Genome Atlas (TCGA) analysis indicated MIF and DDT expression were increased in BCa patients compared to control. 4‐Iodopyridine (4‐IPP), a combined MIF1/MIF2 inhibitor, was more efficacious than ISO‐1, a MIF1‐only inhibitor, in preventing cellular proliferation in BCa cell lines. To evaluate these findings in vivo , wild‐type (WT) and Mif1 −/− animals were exposed to 0.05% BBN in drinking water for 16 weeks to initiate tumorigenesis and then evaluated over the subsequent 4 weeks for tumor formation and progression in the presence or absence of 4‐IPP. 4‐IPP reduced bladder weights in WT animals and bladder weights/tumor stage in Mif1 −/− animals. To determine whether MIF1/MIF2 functioned through CD74 in BCa, WT or Cd74 −/− animals were used in the same BBN model. Although these animals were partially protected against BBN‐induced BCa, 4‐IPP did not enhance this effect. In conclusion, our data suggest that MIF2 mechanistically functions in a similar protumorigenic manner to MIF1, and this is at least partially through CD74. Dual inhibition of MIF homologs is more efficacious at reducing tumor burden in this model of BCa. © 2022 The Pathological Society of Great Britain and Ireland.

Cervical vagal nerve stimulation (VNS) is an FDA approved treatment for epilepsy and depression and is currently being evaluated for treatment of numerous other disorders including pain, anxiety, and inflammation. VNS also received European market approval for heart failure, bronchoconstriction, and diabetes; however, approval for these indications was based on studies in animals, such as dogs and rats, whose vagal nerve size may not have been representative of humans. When subjected to double‐blinded, randomized, sham controlled studies for subsequent U.S. approval, many of these CE‐marked VNS indications failed to meet their primary efficacy endpoints. More than 100,000 patients have undergone VNS, but despite the efficacy of vagal nerve stimulation in a subset of patients, many fail to reach stimulation levels that result in alleviation of symptoms without triggering unwanted side effects. Post hoc studies of the patient population suggested that VNS may not engage the intended fiber pathways in humans, despite engagement in preclinical studies in mouse, rat, or dog. Stimulation parameters were limited in these studies as higher parameters caused side effects such as cough, voice alteration, and dyspnea. Discrepancies between stimulation amplitude needed for intended effect versus unwanted side effect could be directly related to the relative size of the vagus nerve across animal models, variations in fascicle organization, or variations in branching patterns. To address translating improvements in VNS from the lab to the clinic, we evaluated the swine as a potential model for approximating the clinical environment. The size and fascicular organization of the swine vagus nerve is more representative of the human nerve than previously used models. We used a combination of histology, microdissection, and ultrasound to establish a distinct bimodal organization of groups of fascicles stemming from one large fascicle at the inferior (nodose) ganglion, an organization we have termed ‘vagotopy’. We demonstrated that with the use of ultrasound we can visualize the fascicular organization in vivo , an approach that could be used clinically to target stimulation of either sensory fibers or parasympathetic efferents, depending on therapeutic intent. These advances in a clinically relevant model not only inform electrode placement for target engagement, but provide an approach for reduction of side effects. Support or Funding Information Acknowledgements Funded by TL1TR002380 andThe Defense Advanced Research Projects Agency (DARPA) Biological Technologies Office (BTO) Targeted Neuroplasticity Training Program under the auspices of Doug Weber and Tristan McClure‐Begley through the Space and Naval Warfare Systems Command (SPAWAR) Systems Center with (SSC) Pacific grants no. N66001‐17‐2‐4010, and the NIH SPARC Program Award OT2 OD025340.