Citations

Abstract This study explored the role of the ubiquitin-proteasome system (UPS) in dominantly inherited Alzheimer’s disease (DIAD) by examining changes in cerebrospinal fluid (CSF) levels of UPS proteins along with disease progression, AD imaging biomarkers (PiB PET, tau PET), neurodegeneration imaging measures (MRI, FDG PET), and Clinical Dementia Rating® (CDR®). Using the SOMAscan assay, we detected subtle increases in specific ubiquitin enzymes associated with proteostasis in mutation carriers (MCs) up to two decades before the estimated symptom onset. This was followed by more pronounced elevations of UPS-activating enzymes, including E2 and E3 proteins, and ubiquitin-related modifiers. Our findings also demonstrated consistent correlations between UPS proteins and CSF biomarkers such as Aβ42/40 ratio, total tau, various phosphorylated tau species to total tau ratios (ptau181/T181, ptauT205/T205, ptauS202/S202, ptauT217/T217), and MTBR-tau243, alongside Neurofilament light chain (NfL) and the CDR®. Notably, a positive association was observed with imaging markers (PiB PET, tau PET) and a negative correlation with markers of neurodegeneration (FDG PET, MRI), highlighting a significant link between UPS dysregulation and neurodegenerative processes. The correlations suggest that the increase in multiple UPS proteins with rising tau levels and tau-tangle associated markers, indicating a potential role for the UPS in relation to misfolded tau/neurofibrillary tangles (NFTs) and symptom onset. These findings indicate that elevated CSF UPS proteins in DIAD MCs could serve as early indicators of disease progression and suggest a link between UPS dysregulation and amyloid plaque, tau tangles formation, implicating the UPS as a potential therapeutic target in AD pathogenesis.

Cardiac fistulas present diagnostical and therapeutical challenges due to their variability in size, shape and pathway. Three-dimensional printing is increasingly used to provide a tactile representation that aids in preoperative planning and patient education. We present the case of a female in her 60s who developed a fistula between the left ventricle, right atrium and coronary sinus 2 years after bioprosthetic valve replacement. We used three-dimensional modelling to better understand her cardiac anatomy and optimise our surgical approach. She was discharged home without deficit following an uneventful postoperative course. Three-dimensional printing can improve patient care through tangible demonstration, preoperative planning and trainee education.

Background This study sought to characterize the tipping point values (the functional scores that patients deem dysfunctional enough to warrant surgery) for patients undergoing first revision reverse total shoulder arthroplasty (rTSA). Methods This study was a retrospective review of a prospectively collected single-institution database of patients undergoing first revision rTSA between August 2015 and December 2019. Tipping point evaluation utilized preoperative scores including the American Shoulder and Elbow Surgeons (ASES), raw and normalized Constant, Shoulder Pain and Disability Index (SPADI), Simple Shoulder Test (SST), and University of California-Los Angeles (UCLA) scores, and active range of motion including abduction, forward elevation (FE), external rotation (ER), and internal rotation score (IR) prior to elective revision rTSA. Results We included 125 revision rTSAs. Tipping points were 37.6 ASES score, 30.5 raw Constant score, 35.5 normalized Constant score, 68.1 SPADI, 3.7 SST, 13.2 UCLA score, 64° abduction, 69° FE, 23° ER, and 3.1 IR. Higher SST was found for older patients and patients with a lower body mass index. Lower abduction and FE tipping points were reported in patients undergoing revision rTSA for rotator cuff failure, unexplained pain, and implant wear. Discussion These tipping points can help surgeons counsel patients regarding when to undergo revision rTSA. Level of evidence Level III; retrospective cohort study; treatment study.

Background Pulmonary atresia with ventricular septal defect without major aortopulmonary collateral arteries (MAPCAs) is an uncommon form of congenital heart disease. As more patients with congenital heart disease live to adulthood, the objective of this article was to review the long-term results of this specific population. Methods A review of the PubMed database was performed using pertinent key words (pulmonary atresia, tetralogy of Fallot, conduit, right ventricle-pulmonary artery) concentrating on studies from 1990-present and published in English. Most studies of pulmonary atresia-ventricular septal defect patients included those with and without MAPCAs. Analysis included examination of the entire cohort, consideration of the proportion of patients with MAPCAs, and any subgroup analysis of the patients without MAPCAs. Results Survival is approximately 80% at ten years and is improved with complete repair and larger pulmonary arteries. Some studies have found genetic syndromes and extracardiac anomalies to impact survival, while others have not. Incomplete repair has been shown to be associated with worse survival. Independent of initial management strategy, patients with pulmonary atresia and ventricular septal defects without MAPCAs require repeat intervention on the right ventricular outflow tract. Hypoplastic pulmonary arteries have been shown to be a risk factor for reintervention, and decreased conduit durability has been shown with younger age at implantation of conduit. Conclusions Long-term outcomes have improved for patients with pulmonary atresia-ventricular septal defect without MAPCAs, with complete repair and adequate pulmonary arteries favorable for survival. Long-term outcomes include reinterventions, both catheter-based and surgical, predominantly on the right ventricular outflow tract.

TPS5630 Background: Platinum-resistant ovarian cancer (PROC) portends a poor prognosis and, although treatments are available, response rates are low. Previous studies have demonstrated that DNA topoisomerase I (TOP1) inhibitors exhibit clinical activity in PROC. Irinotecan also has a 15-25% response rate in some studies of platinum-resistant epithelial ovarian cancer but does not have FDA approval for this indication. Additional studies in preclinical models suggest that TOP1 poisons are more active if administered at low doses on prolonged schedules. PLX038 is a long-acting prodrug of the potent TOP1 inhibitor SN-38. In PLX038, SN-38 is covalently conjugated to circulating polyethylene glycol and is slowly released at a constant rate to provide the active agent with a long half-life, a low Cmax and very high exposure – important facets for optimal safety and efficacy of this drug. Further, in preclinical studies the nanoparticle prodrug accumulates and is retained in tumors, where it slowly releases the SN-38. Methods: This single arm, phase 2 clinical trial is open at Mayo Clinic in Rochester, MN. The primary endpoint is overall response rate and secondary endpoints include progression-free survival and assessment of tolerability of PLX038. Correlative goals include i) measurement of TOP1-DNA covalent complexes in tumor biopsies and circulating tumor cells to assess successful target engagement; ii) assessment of homologous recombination status and SLFN11 expression for correlation with tumor response rate; and iii) pharmacokinetics of SN-38 and SN-38G as well as their association with GI toxicity. Assessment of gut microbiota and association with GI toxicity profile are also being investigated. Eligible patients include women with platinum resistant high grade serous ovarian, primary peritoneal, and fallopian tube cancer who have received fewer than two prior chemotherapy regimens in the platinum-resistant setting. All patients must have an ECOG performance status of 0, 1, or 2 and adequate bone marrow, renal, and hepatic function. As of January 31, 2024, 12 of planned 37 patients have enrolled. Clinical trial information: NCT05465941 .

OBJECTIVE To compare postprandial glucose excursions following a bolus with inhaled technosphere insulin (TI) or subcutaneous rapid-acting analog (RAA) insulin. RESEARCH DESIGN AND METHODS A meal challenge was completed by 122 adults with type 1 diabetes who were using multiple daily injections (MDI), a nonautomated pump, or automated insulin delivery (AID) and who were randomized to bolus with their usual RAA insulin (n = 61) or TI (n = 61). RESULTS The primary outcome, the treatment group difference in area under the curve for glucose >180 mg/dL over 2 h, was less with TI versus RAA (adjusted difference −12 mg/dL, 95% CI −22 to −2, P = 0.02). With TI, the glucose excursion was smaller (P = 0.01), peak glucose lower (P = 0.01), and time to peak glucose shorter (P = 0.006). Blood glucose <70 mg/dL occurred in one participant in each group. CONCLUSIONS Postmeal glucose excursion was smaller with TI than with RAA insulin in a cohort that included both AID and MDI users.