Clinical Predictors of Overall Survival in Very Elderly Patients With Glioblastoma: A National Cancer Database Multivariable Analysis.

BACKGROUND AND OBJECTIVES: Surgery for the very elderly is a progressively important paradigm as life expectancy continues to rise. Patients with glioblastoma multiforme often undergo surgery, radiotherapy (RT), and chemotherapy (CT) to prolong overall survival (OS). However, the efficacy of these treatment modalities in patients aged 80 years and older has yet to be fully assessed in the literature. METHODS: The National Cancer Database was used to retrospectively identify patients aged 65 years and older with glioblastoma multiforme (1989-2016). All available patient demographic characteristics, disease characteristics, and clinical outcomes were collected. To study OS, bivariable survival models were created using Kaplan-Meier estimates. A Cox proportional-hazards model was used for final adjusted analyses. RESULTS: A total of 578 very elderly patients (aged 80 years and older) and 2836 elderly patients (aged 65-79 years) were identified. Compared with elderly patients, very elderly patients were more likely to have Medicare (odds ratio [OR] 1.899 [95% CI: 1.417-2.544], P < .001) while less likely to have private insurance status (OR 0.544 [95% CI: 0.401-0.739], P < .001). In addition, very elderly patients were more likely to travel the least distance for treatment and have multiple tumors (P < .001). When controlling for demographic and disease characteristics, very elderly patients were less likely to receive gross total resection (GTR) (OR 0.822 [95% CI: 0.681-0.991], P < .041), RT (OR 0.385 [95% CI: 0.319-0.466], P < .001), or postoperative CT (OR 0.298 [95% CI: 0.219-0.359], P < .001) relative to elderly counterparts. Within very elderly patients, GTR, RT, and CT all independently and significantly predicted improved OS (P < .001 for all). These predictive models were deployed in an online calculator (https://spine.shinyapps.io/GBM_elderly). CONCLUSION: Very elderly patients are less likely to receive GTR, RT, or CT when compared with elderly counterparts despite use of these therapies conferring improved OS. Selected very elderly patients may benefit from more aggressive attempts at surgical and adjuvant treatment.

Fractionated radiotherapy after gross-total resection of spinal chordoma: a systematic review of survival outcomes using individualized patient data.

OBJECTIVE: Spinal chordoma treatment guidelines recommend resection. However, in patients in whom gross-total resection (GTR) is achieved, the benefits of radiation therapy (RT) are unclear. Therefore, the authors performed a systematic review to determine if RT is associated with postoperative progression-free survival (PFS) or overall survival (OS) after achieving GTR of spinal chordoma. METHODS: The PubMed database was searched for studies including individualized data of patients undergoing GTR with or without RT for spinal chordoma. Patients < 18 years of age or those who underwent stereotactic body RT were excluded. Qualitative assessment was performed using Newcastle-Ottawa Scale guidelines. Log-rank tests for time-to-event data and a Cox proportional-hazards model were generated for a multivariable statistical model. RESULTS: Complete data of 132 patients were retrieved, with 37 (28%) patients receiving adjuvant RT and 95 (72%) not receiving adjuvant RT. The mean follow-up was not statistically significantly different between those undergoing RT and not undergoing RT (54.02 months and 65.43 months, respectively). Patients were more likely not to undergo RT if their disease was located in the sacrum versus the mobile spine (p < 0.001). When controlling for age ≥ 65 years, male sex, disease location, and treatment year ≥ 2010, patients undergoing RT had similar PFS and OS when compared with those not undergoing RT on multivariable survival analysis (HR 0.935 [95% CI 0.703-2.340], p = 0.844 and HR 2.078 [95% CI 0.848-5.090], p = 0.110, respectively). However, age ≥ 65 years was associated with poorer OS in adjusted analyses (HR 2.761 [95% CI 1.185-6.432], p = 0.018) relative to patients < 65 years of age. CONCLUSIONS: After achieving GTR of spinal chordoma, the utility of RT on PFS and OS remains unclear. Age ≥ 65 years appears to be associated with OS in spinal chordoma patients. Additional multicenter prospective studies are needed to determine the utility of RT in this patient population.

Polarization Saturation in Multilayered Interfacial Ferroelectrics.

Van der Waals polytypes of broken inversion and mirror symmetries  have been recently shown to exhibit switchable electric polarization even at the ultimate two-layer thin limit. Their out-of-plane polarization has been found to accumulate in a ladder-like fashion with each successive layer, offering 2D building blocks for the bottom-up construction of 3D ferroelectrics. Here, it is demonstrated experimentally that beyond a critical stack thickness, the accumulated polarization in rhombohedral polytypes of molybdenum disulfide saturates. The underlying saturation mechanism, deciphered via density functional theory and self-consistent Poisson-Schrödinger calculations, point to a purely electronic redistribution involving: 1. Polarization-induced bandgap closure that allows for cross-stack charge transfer and the emergence of free surface charge; 2. Reduction of the polarization saturation value, as well as the critical thickness at which it is obtained, by the presence of free carriers. The resilience of polar layered structures to atomic surface reconstruction, which is essentially unavoidable in polar 3D crystals, potentially allows for the design of new devices with mobile surface charges. The findings, which are of general nature, should be accounted for when designing switching and/or conductive devices based on ferroelectric layered materials.

Glycemic outcomes and patient satisfaction and self-management improves in transition from standard to virtual multidisciplinary care.

AIMS: With advances in cloud-based technologies, there has been a rise in remote T1D care. We hypothesized that transitioning T1DM care to a virtual, multidisciplinary clinic could improve measures beyond HbA1c. METHODS: To assess the impact of transitioning from standard to virtual T1DM care, we evaluated glycemic measures and patient reported outcomes. RESULTS: Sixty-one adults with T1DM were included, with mean age 40.2 ± 13.5 years and diabetes duration 16.9 ± 9.0 years. Most patients were treated with insulin pumps and CGM. The number of annual diabetes care encounters rose from 2.1 ± 4.2 to 12.8 ± 5.5. Baseline HbA1c was 7.9 ± 1.6 %(63 ± 16.9 mmol/mol), declining to 7.3 ± 1.1 %(56 ± 8.5 mmol/mol) and 7.1 ± 1.0 %(54 ± 7.7 mmol/mol) at 6 and 12 months respectively (p < 0.001 for both). In parallel, TIR improved from 63.1 ± 19.3 % to 69.2 ± 13.8 % (p < 0.001) and 67.5 ± 19.4 % (p = 0.03) at 6 and 12 months respectively, while TBR declined. Scores from validated diabetes treatment and self-management questionnaires rose significantly and these rises were associated with a reduction in HbA1c, the latter score was also associated with increased TIR. There was a trend toward a correlation between encounter frequency and improvement in HbA1c and TIR. CONCLUSIONS: Transitioning from standard to virtual, coordinated, multidisciplinary T1DM care is associated with increased visit frequency, improving glycemic control, treatment satisfaction and self-care behaviors.

Mid-Infrared Mapping of Four-Layer Graphene Polytypes Using Near-Field Microscopy.

The mid-infrared (MIR) spectral region attracts attention for accurate chemical analysis using photonic devices. Few-layer graphene (FLG) polytypes are promising platforms, due to their broad absorption in this range and gate-tunable optical properties. Among these polytypes, the noncentrosymmetric ABCB/ACAB structure is particularly interesting, due to its intrinsic bandgap (8.8 meV) and internal polarization. In this study, we utilize scattering-scanning near-field microscopy to measure the optical response of all three tetralayer graphene polytypes in the 8.5-11.5 µm range. We employ a finite dipole model to compare these results to the calculated optical conductivity for each polytype obtained from a tight-binding model. Our findings reveal a significant discrepancy in the MIR optical conductivity response of graphene between the different polytypes than what the tight-binding model suggests. This observation implies an increased potential for utilizing the distinct tetralayer polytypes in photonic devices operating within the MIR range for chemical sensing and infrared imaging.

Utilizing Neuromodulation in the Treatment of Spinal Cord Injury: An Assessment of Clinical Trials from the National ClinicalTrials.gov Database.

OBJECTIVE: Spinal cord injury (SCI) is responsible for approximately 18,000 trauma cases each year in the United States, often resulting in debilitating motor and autonomic disability. Neuromodulation is a rapidly growing field of interest in the neurosurgical field and has additionally shown promise in the treatment of SCI. This review characterizes all clinical trials to date studying neuromodulation for the treatment of SCI. METHODS: The ClinicalTrials.gov database was queried using the search terms "neuromodulation" and "spinal cord injury" on ClinicalTrials.gov. Trials were excluded if they were not yet recruiting, suspended, terminated early, or of unknown status. RESULTS: In total, 33 clinical trials were included in this study. Of the 33 trials, 8 were completed and 1 had published results. Most trials studied deficits of motor function (60%) and bladder control (37%). Fourteen studies (42.4%) utilized transcutaneous spinal stimulation, 7 (21.2%) utilized epidural electrical stimulation, and 6 (18.2%) utilized tibial nerve stimulation. There was an uptrend of clinical trials studying SCI indexed on PubMed, which was comparable to the increased number of publications indexed overall (Pearson correlation, P < 0.001). Of these, only 1 study regarding home tibial nerve stimulation for neurogenic bladder had published data, which was performed with no adverse events. CONCLUSIONS: Neuromodulation in SCI studies currently assess transcutaneous spinal stimulation, epidural electrical stimulation, and tibial nerve stimulation. There is currently 1 completed study suggesting feasibility of home neuromodulation techniques without adverse events. The results of trials that will be completed in the next few years will help dictate the potential of neuromodulation as a treatment for SCI.

Endoscopic Rhizotomy for Facetogenic Back Pain: A Review of the History, Financial Considerations, Patient Selection Criteria, and Clinical Outcomes.

BACKGROUND: Chronic back pain (CBP) is a condition that places a considerable burden on society, with several million people affected in the United States alone. Treatment options to address this problem and relieve CBP are constantly evolving, and one of the most promising treatment modalities for CBP that is refractory to conservative treatment options is endoscopic rhizotomy (ER). METHODS: A thorough search of the PubMed (MEDLINE) database was conducted to assess the full progression of ER from its earliest uses to present day in a historical narrative review of ER, with treatment of facetogenic pain as a model pathology. RESULTS: ER allows for direct visualization and ablation of sensory branches of the dorsal ramus to provide pain relief in up to 80% of patients faced with refractory CBP. This technique has been built upon since the early 20th century, and the novel endoscopic approach continues to gain popularity among physicians. Benefits of ER include superior postoperative median pain-free duration compared with traditional percutaneous radiofrequency ablation, as well as direct visualization of regional anatomy. Patient selection criteria for the procedure and a modest list of contraindications allow the use of ER as a viable treatment option for a significant population of patients suffering from CBP. Potential barriers to ER include high cost of the procedure, longer intraoperative time, and expensive proprietary equipment. CONCLUSIONS: ER is an effective treatment for refractory CBP with notable advantages. As the technology and popularity of this procedure progress, improvements in the cost, training, and intraoperative time may make it a favorable alternative to the current standard of care.

Violation of expectations is correlated with satisfaction following hip arthroscopy.

PURPOSE: The mechanism by which preoperative expectations may be associated with patient satisfaction and procedural outcomes following hip preservation surgery (HPS) is far from simple or linear. The purpose of this study is to better understand patient expectations regarding HPS and their relationship with patient-reported outcomes (PROs) and satisfaction using machine learning (ML) algorithms. METHODS: Patients scheduled for hip arthroscopy completed the Hip Preservation Surgery Expectations Survey (HPSES) and the pre- and a minimum 2 year postoperative International Hip Outcome Tool (iHOT-33). Patient demographics, including age, gender, occupation, and body mass index (BMI), were also collected. At the latest follow-up, patients were evaluated for subjective satisfaction and postoperative complications. ML algorithms and standard statistics were used. RESULTS: A total of 69 patients were included in this study (mean age 33.7 ± 13.1 years, 62.3% males). The mean follow-up period was 27 months. The mean HPSES score, patient satisfaction, preoperative, and postoperative iHOT-33 were 83.8 ± 16.5, 75.9 ± 26.9, 31.6 ± 15.8, and 73 ± 25.9, respectively. Fifty-nine patients (86%) reported that they would undergo the surgery again, with no significant difference with regards to expectations. A significant difference was found with regards to expectation violation (p < 0.001). Expectation violation scores were also found to be significantly correlated with satisfaction. CONCLUSION: ML algorithms utilized in this study demonstrate that violation of expectations plays an important predictive role in postoperative outcomes and patient satisfaction and is associated with patients' willingness to undergo surgery again. LEVEL OF EVIDENCE: IV.

Cumulative polarization in conductive interfacial ferroelectrics.

Ferroelectricity in atomically thin bilayer structures has been recently predicted1 and measured2-4 in two-dimensional materials with hexagonal non-centrosymmetric unit-cells. The crystal symmetry translates lateral shifts between parallel two-dimensional layers to sign changes in their out-of-plane electric polarization, a mechanism termed 'slide-tronics'4. These observations have been restricted to switching between only two polarization states under low charge carrier densities5-12, limiting the practical application of the revealed phenomena13. To overcome these issues, one should explore the nature of polarization in multi-layered van der Waals stacks, how it is governed by intra- and interlayer charge redistribution and to what extent it survives the addition of mobile charge carriers14. To explore these questions, we conduct surface potential measurements of parallel WSe2 and MoS2 multi-layers with aligned and anti-aligned configurations of the polar interfaces. We find evenly spaced, nearly decoupled potential steps, indicating highly confined interfacial electric fields that provide a means to design multi-state 'ladder-ferroelectrics'. Furthermore, we find that the internal polarization remains notable on electrostatic doping of mobile charge carrier densities as high as 1013 cm-2, with substantial in-plane conductivity. Using density functional theory calculations, we trace the extra charge redistribution in real and momentum spaces and identify an eventual doping-induced depolarization mechanism.

Treatment with Pulsed Extremely Low Frequency Electromagnetic Field (PELF-EMF) Exhibit Anti-Inflammatory and Neuroprotective Effect in Compression Spinal Cord Injury Model.

BACKGROUND: Spinal cord injury (SCI) pathology includes both primary and secondary events. The primary injury includes the original traumatic event, and the secondary injury, beginning immediately after the initial injury, involves progressive neuroinflammation, neuronal excitotoxicity, gliosis, and degeneration. Currently, there is no effective neuroprotective treatment for SCI. However, an accumulating body of data suggests that PELF-EMF has beneficial therapeutic effects on neurotrauma. The purpose of this study was to test the efficacy of the PELF-EMF SEQEX device using a compression SCI mouse model. METHODS: C57BL/6 mice were exposed to PELF-EMF for 4 h on a daily basis for two months, beginning 2 h after a mild-moderate compression SCI. RESULTS: The PELF-EMF treatment significantly diminished inflammatory cell infiltration and astrocyte activation by reducing Iba1, F4/80, CD68+ cells, and GAFP at the lesion borders, and increased pro-survival signaling, such as BDNF, on the neuronal cells. Moreover, the treatment exhibited a neuroprotective effect by reducing the demyelination of the axons of the white matter at the lesion's center. CONCLUSIONS: Treatment with SEQEX demonstrated significant anti-inflammatory and neuroprotective effects. Considering our results, this safe and effective rehabilitative device, already available on the market, may provide a major therapeutic asset in the treatment of SCI.