Faculty Bibliography

BACKGROUND/UNASSIGNED:In this short review/perspective, we asked what the frequencies would be for both postoperative spinal epidural hematomas (SpEH) and postoperative surgical site infections (SSI) in predominantly posterior lumbar procedures performed with or without the placement of wound drains? METHODS/UNASSIGNED:Many spine surgeons are trained to use wound drains to decrease the risk of postoperative SpEH, despite the potential increased risk of SSI. Alternatively, avoiding drains may increase the risk of SpEH but likely decrease the potential for SSI. RESULTS/UNASSIGNED:Performing predominantly posterior lumbar procedures with or without wound drains resulted in largely comparable frequencies of postoperative spinal epidural hematomas (SpEH; range of 0.10%-0.69%) and postoperative surgical site infections (SSI: range of 0.75%-7.3%). Notably, however, two studies documented that drains increased transfusion requirements, with one study showing a prolongation of the in-hospital length of stay. Critically, these series emphasized the importance of early/emergent diagnosis (i.e., with MR) and surgical treatment of SpEH to minimize residual neurological deficits. CONCLUSION/UNASSIGNED:Here, we showed that patients undergoing predominantly lumbar spine surgery performed with or without wound drains demonstrated comparable frequencies of postoperative SpEH and SSI. Nevertheless, spine surgeons must assess on a case-by-case basis whether, based on their education, training, and experience, placing a wound drain is appropriate for their particular patient.

There are more than two million amputees in the USA, and almost all will experience phantom limb sensations (PLS), describing the missing limb as still present. They may also experience intense pain, known as phantom limb pain (PLP), a considerable factor in poor quality of life. In some upper extremity amputees and following brachial plexus avulsion injury (BPAI), hand digits can be detected and mapped to distinct facial skin areas, termed hand-to-face remapping. In this study, we analysed PLS following brachial plexus anaesthesia (BPA) administered prior to upper limb surgeries. Our 39 participants had planned shoulder, wrist or hand surgery. We sought to determine the time course for the emergence of phantom limb experiences after BPA up to the following 24 hours in participants with intact limbs. We also investigated whether there was hand-to-face remapping, suggesting potential cortical reorganization, or changes in proprioception before and after the induction of BPA. Twenty (54%) participants reported PLS immediately after the onset of BPA (T2), and 28 (72%) participants altered proprioception (AP) after surgery (T3). However, neither PLP nor hand mapping onto the face was reported or evoked. PLS were seen earlier than AP. We conclude that PLS arise rapidly after BPA-induced temporary deafferentation of the upper limb and might serve as a model for the permanent deafferentation experienced in individuals with a major upper limb amputation or BPAI. These results contribute to defining a time course for changes after BPA and increase our understanding of how phantom limb phenomena might arise following limb amputation or BPAI.

Chronic inflammatory demyelinating polyneuropathy (CIDP) following viral infections and influenza vaccination has been well documented. However, there have been no confirmed natural influenza A infections leading to development of CIDP. Therefore, we present the case of a 6-year-old male who developed CIDP following a confirmed influenza A infection. Initially presenting with typical flu-like symptoms, the patient experienced a gradual onset of gait instability and leg weakness approximately 1 month later. Despite initial improvement with intravenous immunoglobulin therapy following a diagnosis of Guillain-Barré syndrome, his symptoms relapsed, including lower extremity weakness, incontinence, and sensory loss. Electromyography confirmed a demyelinating polyneuropathy, leading to a diagnosis of CIDP.

BACKGROUND/UNASSIGNED:High intensity focused ultrasound (HiFU) is a relatively new incisionless intervention used for treatment of essential tremor and Parkinson's disease tremor. Understanding the indications, benefits, risks and limitations of HiFU, as well as how it compares to deep brain stimulation (DBS), is important in guiding appropriate recommendations for prospective patients. METHODS/UNASSIGNED:Current literature on efficacy and safety of HiFU in essential tremor and Parkinson's disease was reviewed. We additionally reviewed data on the patients who presented to our center for HiFU consultation, including outcomes of patients with low skull density ratios, and distances traveled for the procedure. RESULTS/DISCUSSION/UNASSIGNED:HiFU is an effective and generally well-tolerated treatment for tremor. Adverse events, especially gait instability, are typically temporary but should be discussed with patients. The risk of tremor recurrence in certain patients with Parkinson's disease is also of note. Identifying appropriate candidates for either intervention remains crucial and involves considering each patient's circumstances and preferences, potential adverse effects, and practical aspects like access to follow-up and expectations. Data on bilateral HiFU lesioning, use of HiFU in patients with low skull density ratios, and emerging targets like the pallidothalamic tract are discussed as well.

High-dimensional multinomial regression models are very useful in practice but have received less research attention than logistic regression models, especially from the perspective of statistical inference. In this work, we analyze the estimation and prediction error of the contrast-based

Ubiquitin-dependent proteolysis regulates diverse cellular functions with high substrate specificity, which hinges on the ability of ubiquitin E3 ligases to decode the targets' degradation signals, i.e., degrons. Here, we show that BACH1, a transcription repressor of antioxidant response genes, features two distinct unconventional degrons encrypted in the quaternary structure of its homodimeric BTB domain. These two degrons are both functionalized by oxidative stress and are deciphered by two complementary E3s. FBXO22 recognizes a degron constructed by the BACH1 BTB domain dimer interface, which is unmasked from transcriptional co-repressors after oxidative stress releases BACH1 from chromatin. When this degron is impaired by oxidation, a second BACH1 degron manifested by its destabilized BTB dimer is probed by a pair of FBXL17 proteins that remodels the substrate into E3-bound monomers for ubiquitination. Our findings highlight the multidimensionality of protein degradation signals and the functional complementarity of different ubiquitin ligases targeting the same substrate.

BACKGROUND:) are associated with important clinical outcomes during hospitalization and improve the performance of clinical prediction models of potentially lethal malignant edema (PLME). METHODS:using area under the curve. RESULTS:was significantly associated with higher odds of PLME when adjusting for confounders (OR 1.69, 95% CI 1.49 to 2.0), and improved model discrimination compared with existing models and models using baseline ASPECTS. Deep territory involvement (OR 2.46, 95% CI 1.53 to 4.01) and anterior territory involvement (OR 3.23, 95% CI 1.88 to 5.71) were significantly associated with PLME. CONCLUSIONS:information improved discrimination of established edema prediction models and could be used immediately to help facilitate clinical management decisions and prognostication.

UNLABELLED:The superior hypophyseal arteries (SHAs) are well known in anatomical and surgical literature, with a well-established role in supply of the anterior hypophysis and superjacent optic apparatus. However, due to small size and overlap with other vessels, in vivo imaging by any modality has been essentially non-existent. Advances in high resolution cone beam CT angiography (CBCTA) now enables this deficiency to be addressed. This paper presents, to the best of our knowledge, the first comprehensive in vivo imaging evaluation of the SHAs. METHODS:Twenty-five CBCTA studies of common or internal carotid arteries were obtained for a variety of clinical reasons. Dedicated secondary reconstructions of the siphon were performed, recording the presence, number, and supply territory of SHAs. A spectrum approach, emphasizing balance with adjacent territories (inferior hypophyseal, ophthalmic, posterior and communicating region arteries) was investigated. RESULTS:The SHAs were present in all cases. Supply of the anterior pituitary was nearly universal (96%) and almost half (44%) originated from the 'cave' region, in excellent agreement with surgical literature. Optic apparatus supply was more difficult to adjudicate, but appeared present in most cases. The relationship with superior hypophyseal aneurysms was consistent. Patency following flow diverter placement was typical, despite a presumably rich collateral network. Embryologic implications with respect to the ophthalmic artery and infraoptic course of the anterior cerebral artery are intriguing. CONCLUSIONS:SHAs are consistently seen with CBCTA, allowing for correlation with existing anatomical and surgical literature, laying the groundwork for future in vivo investigation.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Accumulating evidence points to worse clinical outcomes among adults with multiple sclerosis (MS) belonging to minority or poverty-affected groups. By contrast, little is known about the outcomes of these populations with pediatric-onset MS (POMS). Individuals with POMS represent 5% of the MS population and are more racially diverse yet have been understudied regarding socioeconomic environment or characteristics. In this study, we investigated the association between childhood social determinants of health (SDOH) and brain MRI outcomes in patients with POMS. METHODS:This is a retrospective single-site cohort study of patients with POMS with brain MRI quantitatively analyzed using icobrain software to yield total white matter lesion, black hole, whole brain, white matter, and gray matter volumes. All patients with POMS evaluated at New York University Langone MS Center and who underwent high-quality volumetric MRI scans were included in this study. SDOH indicators of race, ethnicity, health insurance type, parental education, and childhood neighborhood social vulnerability index (SVI) were examined for association with MRI outcomes using linear least absolute shrinkage selection operator penalized regression modeling. Disease-modifying therapy (DMT) timing and DMT efficacy were compared for each SDOH category. RESULTS:= 0.39). There were no differences in DMT timing or efficacy between categories of social disadvantage. DISCUSSION/CONCLUSIONS:Individual-level and neighborhood-level indicators of social disadvantage are associated with worse brain MRI outcomes in POMS. Further investigation of race, ethnicity, and childhood disadvantage as risk factors of MS susceptibility and severity is needed to reduce MS health disparities.

Transcripts of the KRAS locus are alternatively spliced to generate two proteins, KRAS4A and KRAS4B, which differ in their membrane-targeting sequences. These splice variants have been conserved for more than 450 million years, suggesting non-overlapping functions driven by differential membrane association. Here, we use proximity labeling to map the differential interactomes of the KRAS splice variants. We find 24 and 10 proteins that interact specifically with KRAS4A or KRAS4B, respectively. The KRAS interacting protein most specific to KRAS4A is BIRC6, a large member of the inhibitor of apoptosis protein family unique in possessing E2/E3 ubiquitin ligase activity. We find that this interaction takes place on the Golgi apparatus and results in the mono- and di-ubiquitination of KRAS4A at lysines 128 and 147. Silencing BIRC6 diminishes GTP loading of and growth stimulation by KRAS4A but not KRAS4B. Thus, BIRC6 is a ubiquitin ligase that inhibits apoptosis and also modifies KRAS4A.