Citations

Abstract The functional significance of the interactions between proteins in living cells to form short-lived quaternary structures cannot be overemphasized. Yet, quaternary structure information is not captured by current methods, neither can those methods determine structure within living cells. The dynamic versatility, abundance, and functional diversity of G protein-coupled receptors (GPCRs) pose myriad challenges to existing technologies but also present these proteins as the ideal testbed for new technologies to investigate the complex inter-regulation of receptor-ligand, receptor-receptor, and receptor-downstream effector interfaces in living cells. Here, we present development and use of a novel method capable of overcoming existing challenges by combining distributions (or spectrograms) of FRET efficiencies from populations of fluorescently tagged proteins associating into oligomeric complexes in live cells with diffusion-like trajectories of FRET donors and acceptors obtained from molecular dynamics (MD) simulations. Our approach provides an atom-level picture of the binding interfaces within oligomers of the human secretin receptor (hSecR) in live cells and allows for extraction of mechanistic insights into the function of GPCRs oligomerization. This FRET-MD spectrometry approach is a robust platform for investigating protein-protein binding mechanisms and opens a new avenue for investigating stable as well as fleeting quaternary structures of any membrane proteins in living cells.

Abstract Background Pulsed‐field ablation (PFA) has emerged as an innovative alternative to radiofrequency (RF) and cryoablation because it selectively targets myocardial tissue. Thus, we aim to estimate the efficacy and safety of PFA versus thermal ablation for atrial fibrillation (AF) ablation. Methods A systematic review and meta‐analysis were retrieved from PubMed, WOS, SCOPUS, EMBASE, and CENTRAL through September 2023. We used RevMan V. 5.4 to pool dichotomous data using risk ratio (RR) and continuous data using mean difference (MD) with a 95% confidence interval (CI). PROSPERO ID: CRD42023480321 Results We included 17 studies with a total of 2255 patients. PFA was significantly associated with a decreased incidence of AF recurrence (RR: 0.66 with 95% CI [0.51, 0.87], p = .003). However, there was no significant difference between PFA and thermal ablation in arrhythmia recurrence (RR: 0.92 with 95% CI [0.74, 1.46], p = .42). PFA was significantly associated with decreased total procedure time (MD: −15.15 with 95% CI [−20.23, −10.07], p < .00001), decreased heart rate change (MD: −7.39 with 95% CI [−12.16, −2.62], p = .002), decreased phrenic nerve palsy (RR: 0.38 with 95% CI [0.15, 0.98], p = .05), and reduced esophageal lesions (RR: 0.09 with 95% CI [0.01, 0.69], p = .02). On the contrary, PFA was significantly associated with increased pericardial tamponade (RR: 6.14 with 95% CI [1.43, 26.33], p = .01). Conclusion PFA was significantly associated with decreased AF recurrence, total procedure time, heart rate change, phrenic nerve palsy, esophageal lesion, and increased incidence of pericardial tamponade compared with thermal ablation.

Abstract Objectives To examine the clinicopathologic features of patients with polymyalgia rheumatica (PMR) who had thoracic aorta repair surgery. Findings were compared with those of a cohort of patients with giant cell arteritis (GCA) requiring thoracic aorta repair. Methods All patients evaluated at Mayo Clinic in Rochester, MN, with Current Procedural Terminology (CPT) codes for thoracic aorta repair surgery between 2000–2021 were identified. All patients were screened for prior PMR diagnosis. Patients with PMR and no signs of GCA were categorized as clinically isolated PMR. The medical records of all patients were manually reviewed, and pathologists re-examined all the aortic tissues. Results Of the 4621 patients with at least one CPT code for thoracic aorta repair surgery, 43 patients were diagnosed with clinically isolated PMR before the surgery. Detailed histopathological examination of the aortic tissues revealed active inflammation in 30/43 (70%) patients after a median (IQR) of 10.0 (4.7–13.3) years from the PMR diagnosis. When compared with aortic tissue from patients with a prior diagnosis of GCA, the aorta of patients with PMR had more severe inflammation (Grade 3: 15/30 [50%] vs 5/34 [15%], P = 0.002). Patients with PMR and thoracic aorta repair may experience a 40% increased risk of mortality compared with the general population, but this did not reach statistical significance (standardized mortality ratio: 1.40; 95% CI: 0.91–2.07). Conclusions Some patients with PMR have subclinical aortic inflammation that is detectable many years after initial diagnosis and may contribute to the development of aortic aneurysm.

Background: The epigenome, the set of modifications to DNA and associated molecules that control gene expression, cellular identity, and function, plays a major role in mediating cellular responses to outside factors. Thus, evaluation of the epigenetic state can provide insights into cellular adaptions occurring over the course of disease. Methods: We performed epigenome-wide association studies of primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC) using the Illumina MethylationEPIC Bead Chip. Results: We found evidence of increased epigenetic age acceleration and differences in predicted immune cell composition in patients with PSC and PBC. Epigenetic profiles demonstrated differences in predicted protein levels including increased levels of tumor necrosis factor receptor superfamily member 1B in patients with cirrhotic compared to noncirrhotic PSC and PBC. Epigenome-wide association studies of PSC discovered strongly associated 5′-C-phosphate-G-3′ sites in genes including vacuole membrane protein 1 and SOCS3, and epigenome-wide association studies of PBC found strong 5′-C-phosphate-G-3′ associations in genes including NOD-like receptor family CARD domain containing 5, human leukocyte antigen-E, and PSMB8. Analyses identified disease-associated canonical pathways and upstream regulators involved with immune signaling and activation of macrophages and T-cells. A comparison of PSC and PBC data found relatively little overlap at the 5′-C-phosphate-G-3′ and gene levels with slightly more overlap at the level of pathways and upstream regulators. Conclusions: This study provides insights into methylation profiles of patients that support current concepts of disease mechanisms and provide novel data to inspire future research. Studies to corroborate our findings and expand into other -omics layers will be invaluable to further our understanding of these rare diseases with the goal to improve and individualize prognosis and treatment.

Background: Nurtec, a versatile migraine medication, has gained popularity. However, the awareness of migraine surgery remains uncertain. Methods: Following a descriptive approach, this cross-sectional study used Google Trends data as of December 1, 2023, to analyze internet search patterns. Approval from Vanderbilt University’s institutional review board and adherence to Strengthening the Reporting of Observational Studies in Epidemiology guidelines were confirmed. Monthly relative search volume (RSV) data for “migraine surgery,” “Nurtec,” and “Rimegepant” were collected from January 1, 2004, to November 11, 2023, within the United States. Statistical analysis involved determining mean monthly RSV values and percentage changes for critical periods. Results: For “Nurtec,” a significant surge in RSV occurred from March 2020 to April 2020 (344%). Additional peaks were observed from June 2020 to July 2020 (66%), October 2020 to December 2020 (169%), May 2021 to June 2021 (33%), and May 2023 to June 2023 (14%). “Migraine surgery” exhibited a notable 400% increase in RSV, from March 2005 to May 2005. However, post-2006, RSV for “migraine surgery” consistently remained low without noticeable peaks. Conclusions: The analysis of RSV trends for “Nurtec” and “migraine surgery” from 2004 to 2023 reveals the impact of pivotal events and marketing strategies on public interest. The distinct peaks in “Nurtec” RSV align with Food & Drug Administration approvals and marketing campaigns, highlighting the medication’s accessibility. Conversely, the consistently low RSV for “migraine surgery” indicates limited awareness, emphasizing the need for enhanced promotion and education regarding surgical interventions.

Key Points Morphometry allows for a more prognostic multidimensional quantification of interstitial fibrosis and tubular atrophy (IFTA) in kidneys than does visual inspection. The density of IFTA foci is determined by dividing the number of contiguous IFTA patches in the kidney cortex by the area of cortex. Higher density of IFTA foci significantly predicted renal allograft failure beyond %IFTA and other biopsy and clinical characteristics. Background Contraction of interstitial fibrosis and tubular atrophy (IFTA) may cause %IFTA to under-represent the severity of nephron loss. Higher density of IFTA foci is an important predictor of progressive CKD in native kidneys independent of %IFTA. Methods We studied kidney transplant recipients transplanted between 2000 and 2013 who had a 5-year surveillance kidney biopsy and subsequent follow-up. Banff ci score (interstitial fibrosis) was obtained from the pathology reports. After digitizing the biopsies, we traced cortex area and each distinct IFTA focus on a single trichrome-stained section. Percent IFTA area and IFTA foci density (count of IFTA foci/cortex area) were calculated. Cox models assessed the risk of death-censored graft failure after the 5-year biopsy with Banff ci score, morphometric %IFTA, and IFTA foci density. Results There were 58 death-censored allograft failures among 835 kidney recipients during the 5 years of follow-up. Biopsies from grafts that failed had higher mean Banff ci score (1.5 versus 0.7, P < 0.0001), %IFTA (22.6% versus 7.0%, P < 0.0001), and IFTA foci density (1.3/mm 2 versus 0.4/mm 2 , P < 0.0001). After adjusting for other Banff scores or clinical variables, Banff ci did not correlate with allograft failure, but both higher %IFTA (hazard ratio = 1.56, P < 0.0001) and higher IFTA foci density (hazard ratio = 2.34, P < 0.0001) did. All but four allograft failures by 10 years had biopsies in the top quartile of either %IFTA or IFTA foci density at 5 years. A model using just these two morphometric measures without clinical characteristics resulted in a c-statistic of 0.891 with respect to allograft failure. Conclusions Morphometric characterization of IFTA foci density is a strong predictor of death-censored allograft failure not captured in current Banff classification for grading of kidney fibrosis.