Integrated systems approach identifies genetic nodes and networks in late-onset Alzheimer's disease.

The genetics of complex disease produce alterations in the molecular interactions of cellular pathways whose collective effect may become clear through the organized structure of molecular networks. To characterize molecular systems associated with late-onset Alzheimer's disease (LOAD), we constructed gene-regulatory networks in 1,647 postmortem brain tissues from LOAD patients and nondemented subjects, and we demonstrate that LOAD reconfigures specific portions of the molecular interaction structure. Through an integrative network-based approach, we rank-ordered these network structures for relevance to LOAD pathology, highlighting an immune- and microglia-specific module that is dominated by genes involved in pathogen phagocytosis, contains TYROBP as a key regulator, and is upregulated in LOAD. Mouse microglia cells overexpressing intact or truncated TYROBP revealed expression changes that significantly overlapped the human brain TYROBP network. Thus the causal network structure is a useful predictor of response to gene perturbations and presents a framework to test models of disease mechanisms underlying LOAD.

A member of the claudin superfamily influences formation of the front domain in pheromone-responding yeast cells.

Cell polarization in response to chemical gradients is important in development and homeostasis across eukaryota. Chemosensing cells orient toward or away from gradient sources by polarizing along a front-rear axis. Using the mating response of budding yeast as a model of chemotropic cell polarization, we found that Dcv1, a member of the claudin superfamily, influences front-rear polarity. Although Dcv1 localized uniformly on the plasma membrane (PM) of vegetative cells, it was confined to the rear of cells responding to pheromone, away from the pheromone receptor. dcv1Δ conferred mislocalization of sensory, polarity and trafficking proteins, as well as PM lipids. These phenotypes correlated with defects in pheromone-gradient tracking and cell fusion. We propose that Dcv1 helps demarcate the mating-specific front domain primarily by restricting PM lipid distribution.

Rich Landscape of Colloidal Semiconductor-Metal Hybrid Nanostructures: Synthesis, Synergetic Characteristics, and Emerging Applications.

Nanochemistry provides powerful synthetic tools allowing one to combine different materials on a single nanostructure, thus unfolding numerous possibilities to tailor their properties toward diverse functionalities. Herein, we review the progress in the field of semiconductor-metal hybrid nanoparticles (HNPs) focusing on metal-chalcogenides-metal combined systems. The fundamental principles of their synthesis are discussed, leading to a myriad of possible hybrid architectures including Janus zero-dimensional quantum dot-based systems and anisotropic quasi 1D nanorods and quasi-2D platelets. The properties of HNPs are described with particular focus on emergent synergetic characteristics. Of these, the light-induced charge-separation effect across the semiconductor-metal nanojunction is of particular interest as a basis for the utilization of HNPs in photocatalytic applications. The extensive studies on the charge-separation behavior and its dependence on the HNPs structural characteristics, environmental and chemical conditions, and light excitation regime are surveyed. Combining the advanced synthetic control with the charge-separation effect has led to demonstration of various applications of HNPs in different fields. A particular promise lies in their functionality as photocatalysts for a variety of uses, including solar-to-fuel conversion, as a new type of photoinitiator for photopolymerization and 3D printing, and in novel chemical and biomedical uses.

De novo assembly and annotation of the Patagonian toothfish (Dissostichus eleginoides) genome.

BACKGROUND: Patagonian toothfish (Dissostichus eleginoides) is an economically and ecologically important fish species in the family Nototheniidae. Juveniles occupy progressively deeper waters as they mature and grow, and adults have been caught as deep as 2500 m, living on or in just above the southern shelves and slopes around the sub-Antarctic islands of the Southern Ocean. As apex predators, they are a key part of the food web, feeding on a variety of prey, including krill, squid, and other fish. Despite its importance, genomic sequence data, which could be used for more accurate dating of the divergence between Patagonian and Antarctic toothfish, or establish whether it shares adaptations to temperature with fish living in more polar or equatorial climes, has so far been limited. RESULTS: A high-quality D. eleginoides genome was generated using a combination of Illumina, PacBio and Omni-C sequencing technologies. To aid the genome annotation, the transcriptome derived from a variety of toothfish tissues was also generated using both short and long read sequencing methods. The final genome assembly was 797.8 Mb with a N50 scaffold length of 3.5 Mb. Approximately 31.7% of the genome consisted of repetitive elements. A total of 35,543 putative protein-coding regions were identified, of which 50% have been functionally annotated. Transcriptomics analysis showed that approximately 64% of the predicted genes (22,617 genes) were found to be expressed in the tissues sampled. Comparative genomics analysis revealed that the anti-freeze glycoprotein (AFGP) locus of D. eleginoides does not contain any AFGP proteins compared to the same locus in the Antarctic toothfish (Dissostichus mawsoni). This is in agreement with previously published results looking at hybridization signals and confirms that Patagonian toothfish do not possess AFGP coding sequences in their genome. CONCLUSIONS: We have assembled and annotated the Patagonian toothfish genome, which will provide a valuable genetic resource for ecological and evolutionary studies on this and other closely related species.

Impact of Chronic Kidney Disease on Outcomes following Vascular Procedure in the Vascular Quality Initiative.

BACKGROUND: Chronic kidney disease (CKD) increases morbidity and mortality in most vascular procedures. However, a binary classification of estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2, which is often used in both modeling and clinical trials, may not be optimal for predicting clinical outcomes. OBJECTIVE: Determine the optimal eGFR cutoff for use in risk stratification and prediction models. METHODS: Vascular Quality Initiative (VQI) data for non-emergent, first-time OAR, EVAR, TEVAR, CEA, CAS, PVI, Supra- and infra-inguinal bypass were analyzed from to 2013-2023 and divided into cohorts based on eGFR (≥60, 45-59, 30-44, <30, and preoperative dialysis). χ2 and logistic regression were used to evaluate perioperative outcomes. RESULTS: Compared to patients with eGFR ≥60, those with eGFR 45-59 had similar odds of mortality following all procedures, except TEVAR. Driven by this group, the combined cohort showed a slight increase in the odds of mortality for eGFR 45-59 (0.6% vs. 0.7%, aOR 1.16, P=0.002). Those in the 30-44 group demonstrated increased odds of mortality both overall and in the individual procedure groups (0.6% vs. 1.2%, aOR 1.78, P<0.001). The odds of mortality continued to increase with worsening eGFR. The overall rate of new permanent dialysis was low for all eGFR cohorts, with a 0.02% difference between those with eGFR >60 and those in the 45-59 cohort (0.04% vs. 0.06%; a OR 1.65, P<0.001). The odds of permanent dialysis likewise continued to increase with decreasing eGFR. CONCLUSIONS: Rather than a binary eGFR cutoff of ≥60 and <60 to stratify patient risk, better risk stratification may be achieved by using five groups of ≥60, 45-59, 30-44, <30, and preoperative dialysis.

Association of Surgeon Self-Reported Gender and Surgical Outcomes in Current US Practice.

OBJECTIVE: This study aimed to evaluate the association of surgeon self-reported gender on clinical outcomes in contemporary US surgical practice. BACKGROUND: Previous research has suggested that there are potentially improved surgical outcomes for female surgeons, yet the underlying causal path for this association remains unclear. METHODS: Using the Vizient Clinical Database(2016-2021), 39 operations categorized by the CDC's National Healthcare Safety Network were analyzed. The surgeon self-reported gender as the primary exposure. The primary outcome was a composite of in-hospital death, complications, and/or 30-day readmission. Multivariable logistic regression and propensity score matching were used for risk adjustment. RESULTS: The analysis included 4,882,784 patients operated on by 11,955 female surgeons (33% of surgeons performing 21% of procedures) and 23,799 male surgeons (67% of surgeons performing 79% of procedures). Female surgeons were younger (45±9 vs males-53±11 y; P <0.0001) and had lower operative volumes. Unadjusted incidence of the primary outcome was 13.6%(10.7%-female surgeons, 14.3%-male surgeons; P <0.0001). After propensity matching, the primary outcome occurred in 13.0% of patients [12.9%-female, 13.0%-male; OR (M vs. F)=1.02, 95% CI: 1.01-1.03; P =0.001), with female surgeons having small statistical associations with lower mortality and complication rates but not readmissions. Procedure-specific analyses revealed inconsistent or no surgeon-gender associations. CONCLUSIONS: In the largest analysis to date, surgeon self-reported gender had a small statistical, clinically marginal correlation with postoperative outcomes. The variation across surgical specialties and procedures suggests that the association with surgeon gender is unlikely causal for the observed differences in outcomes. Patients should be reassured that surgeon gender alone does not have a clinically meaningful impact on their outcome.

Decision aids for patients with carotid stenosis.

BACKGROUND: Shared decision-making tools have been underused by clinicians in real-world practice. Changes to the National Coverage Determination by Medicare for carotid stenting greatly expand the coverage for patients, but simultaneously require a shared decision-making interaction that involves the use of a validated tool. Accordingly, our objective was to evaluate the currently available decision aids for carotid stenosis. METHODS: We conducted a review of the literature for published work on decision aids for the treatment of carotid disease. RESULTS: Four publications met inclusion criteria. We found the format of the decision aid impacted patient comprehension and decision making, although patient characteristics also played a role in the therapeutic decisions made. Notably, none of the available decision aids included the widely adopted transcarotid artery revascularization as an option. CONCLUSIONS: Further work is needed in the development of a widespread validated decision aid instrument for patients with carotid stenosis.

Patient decision-making in the era of transcarotid artery revascularization.

OBJECTIVE: The National Coverage Determination on carotid stenting by Medicare in October 2023 stipulates that patients participate in a shared decision-making (SDM) conversation with their proceduralist before an intervention. However, to date, there is no validated SDM tool that incorporates transcarotid artery revascularization (TCAR) into its decision platform. Our objective was to elicit patient and surgeon experiences and preferences through a qualitative approach to better inform the SDM process surrounding carotid revascularization. METHODS: We performed longitudinal perioperative semistructured interviews of 20 participants using purposive maximum variation sampling, a qualitative technique designed for identification and selection of information-rich cases, to define domains important to participants undergoing carotid endarterectomy or TCAR and impressions of SDM. We also performed interviews with nine vascular surgeons to elicit their input on the SDM process surrounding carotid revascularization. Interview data were coded and analyzed using inductive content analysis coding. RESULTS: We identified three important domains that contribute to the participants' ultimate decision on which procedure to choose: their individual values, their understanding of the disease and each procedure, and how they prefer to make medical decisions. Participant values included themes such as success rates, "wanting to feel better," and the proceduralist's experience. Participants varied in their desired degree of understanding of carotid disease, but all individuals wished to discuss each option with their proceduralist. Participants' desired medical decision-making style varied on a spectrum from complete autonomy to wanting the proceduralist to make the decision for them. Participants who preferred carotid endarterectomy felt outcomes were superior to TCAR and often expressed a desire to eliminate the carotid plaque. Those selecting TCAR felt it was a newer, less invasive option with the shortest procedural and recovery times. Surgeons frequently noted patient factors such as age and anatomy, as well as the availability of long-term data, as reasons to preferentially select one procedure. For most participants, their surgeon was viewed as the most important source of information surrounding their disease and procedure. CONCLUSIONS: SDM surrounding carotid revascularization is nuanced and marked by variation in patient preferences surrounding autonomy when choosing treatment. Given the mandate by Medicare to participate in a SDM interaction before carotid stenting, this analysis offers critical insights that can help to guide an efficient and effective dialog between patients and providers to arrive at a shared decision surrounding therapeutic intervention for patients with carotid disease.

A patient-centered textbook outcome measure effectively discriminates contemporary elective open abdominal aortic aneurysm repair quality.

BACKGROUND: There is persistent controversy surrounding the merit of surgical volume benchmarks being used solely as a sufficient proxy for assessing the quality of open abdominal aortic aneurysm (AAA) repair. Importantly, operative volume quotas may fail to reflect a more nuanced and comprehensive depiction of surgical outcomes most relevant to patients. Accordingly, we herein propose a patient-centered textbook outcome (TO) for AAA repair that is analogous to other large magnitude extirpative operations performed in other surgical specialties, and test its feasibility to discriminate hospital performance using Society for Vascular Surgery (SVS) volume guidelines. METHODS: All elective open infrarenal AAA repairs (OAR) in the SVS-Vascular Quality Initiative were examined (2009-2022). The primary end point was a TO, defined as a composite of no in-hospital complication or reintervention/reoperation, length of stay of ≤10 days, home discharge, and 1-year survival rates. The discriminatory ability of the TO measure was assessed by comparing centers that did or did not meet the SVS annual OAR volume threshold recommendation (high volume ≥10 OARs/year; low volume <10 OARs/year). Logistic regression and multivariable models adjusted for patient and procedure-related differences. RESULTS: A total of 9657 OARs across 198 centers were analyzed (mean age, 69.5 ± 8.4 years; female, 26%; non-White, 12%). A TO was identified in 44% (n = 4293) of the overall cohort. The incidence of individual TO components included no in-hospital complication (61%), no in-hospital reintervention or reoperation (92%), length of stay of ≤10 days (78%), home discharge (76%), and 1-year survival (91%). Median annual center volume was 6 (interquartile range, 3-10) and a majority of centers did not meet the SVS volume suggested threshold (<10 OARs/year, n = 148 [74%]). However, most patients (6265 of 9657 [65%]) underwent OAR in high-volume hospitals. When comparing high- and low-volume centers, a TO was more likely to occur in high-volume institutions: ≥10 OARs/year (46%) vs <10 OARs/year (42%; P = .0006). The association of a protective effect for higher center volume remained after risk adjustment (odds ratio, 1.1; 95% confidence interval, 1.05-1.26; P = .003). CONCLUSIONS: TOs for elective OAR reflect a more nuanced and comprehensive patient centered proxy to measure care delivery, consistent with other surgical specialties. Surprisingly, a TO was achieved in <50% of elective AAA cases nationally. Although the likelihood of a TO seems to correlate with SVS center volume recommendations, it more importantly reflects elements which may be prioritized by patients and thus offers insights into further improving real-world AAA care.

Changes in global mortality from aortic aneurysm.

OBJECTIVE: Globally, there has been a marked increase in aortic aneurysm-related deaths between 1990 and 2019. We sought to understand the underlying etiologies for this mortality trend by examining secular changes in both demographics and the prevalence of risk factors, and how these changes may vary across sociodemographic index (SDI) regions. METHODS: We queried the Global Burden of Disease Study (GBD) for aortic aneurysm deaths from 1990 to 2019 overall and by age group. We identified the percentage of aortic aneurysm deaths attributable to each risk factor identified by GBD modeling (smoking, hypertension, lead exposure, and high sodium diet) and their respective changes over time. We then analyzed aneurysm mortality by SDI region. RESULTS: The number of aortic aneurysm-related deaths have increased from 94,968 in 1990 to 172,427 in 2019, signifying an 81.6% increase, which greatly exceeds the 18.2% increase in all-cause mortality observed over the same time interval. Examination of age-specific mortality demonstrated that the number of aortic aneurysm deaths markedly correlated with advancing age. However, when considering rate of death rather than mortality count, overall age-standardized death rates decreased 18% from 2.72 per 100,000 in 1990 to 2.21 per 100,000 in 2019. Analysis of the specific risk factors associated with aneurysm death revealed that the percentage of deaths attributable to smoking decreased from 45.6% in 1990 to 34.6% in 2019, and deaths attributable to hypertension decreased from 38.7% to 34.7%. Globally, hypertension surpassed smoking as the leading risk factor. The reported rate of death was consistently greater as SDI increased, and this effect was most pronounced among low-middle and middle SDI regions (173.2% and 170.4%, respectively). CONCLUSIONS: Despite an overall increase in the number of aneurysm deaths, there was a decrease in the age-standardized death rate, demonstrating that the observed increased number of aortic aneurysm deaths between 1990 and 2019 was primarily driven by an overall increase in the age of the global population. Fortunately, it appears that the increase in overall aneurysm-related deaths has been modulated by improved risk factor modification, in particular smoking. Given the rise in aneurysm-related deaths, global expansion of vascular specialty capabilities is warranted and will serve to amplify improvements in population-based aneurysm health achieved with risk factor control.

Disease-specific patient-reported quality of life after fenestrated/branched endovascular aortic aneurysm repair.

OBJECTIVES: Fenestrated-branched endovascular technology (F/B-EVAR) is increasingly used to repair complex aortic aneurysms. While reintervention, morbidity and mortality after F/B-EVAR have been well-characterized, studies on patient-reported quality of life (QOL) after F/B-EVAR have been limited in their use of non-specific instruments and measures. We report on disease-specific QOL in patients that underwent F/B-EVAR using a validated QOL survey for aortic aneurysms. METHODS: Prospectively maintained databases were used to contact living patients that underwent F/B-EVAR for pararenal or thoracoabdominal aortic aneurysms at two institutions. Eligible patients (n = 286) were asked to complete a disease-specific QOL survey previously validated in patients that underwent repair of an infrarenal abdominal aortic aneurysm. An emotional impact score (EIS) from 0-100 was derived from the survey with higher scores indicating more emotional impact and worse QOL. Respondent behavior change following F/B-EVAR was evaluated in four domains (strenuous activity, travel, heavy lifting, and sexual activity) previously identified by patients to be most impacted by an aortic aneurysm. RESULTS: In total, 234 patients (82%) completed surveys. Mean post-operative interval to survey completion was 3.4 ± 2.8 years. Mean EIS was 16 (range 0-91) for all patients surveyed, with higher mean EIS among those within the first year after F/B-EVAR (20 vs 14). Most respondents demonstrated limited adverse emotional impact after F/B-EVAR. However, the 4th quartile of EIS was broad (22-91), indicating that a subset of respondents had significantly worse QOL after repair. While most patients reported no post-procedure change in each of the activity domains, over 40% of patients did report decrease in strenuous activity and heavy lifting after F/B-EVAR. Those with decreased activity after repair had corresponding deficiencies in disease-specific knowledge for the domains of heavy lifting (P <.001) and sexual activity (P = .17). CONCLUSIONS: The majority of patients who underwent F/B-EVAR in this cohort had low emotional impact on their QOL after repair. One-quarter of patients did report significant post-procedure anxiety about their aneurysm, with improvement observed beyond one year after repair. Most patients reported unchanged or decreased activity levels following F/B-EVAR, and less aneurysm-specific patient knowledge was associated with decreased activity after repair. These findings are similar to those seen in prior work using this survey instrument in patients that underwent infrarenal aneurysm repair. This work confirms the feasibility of using this survey to evaluate QOL in patients with complex aortic disease. Longitudinal evaluation in these patients may identify those at high-risk for worse QOL after F/B-EVAR.

Size thresholds for repair of abdominal aortic aneurysms warrant reconsideration.

BACKGROUND: The historical size threshold for abdominal aortic aneurysm (AAA) repair is widely accepted to be 5.5 cm for men and 5.0 cm for women. However, contemporary AAA rupture risks may be lower than historical benchmarks, which has implications for when AAAs should be repaired. Our objective was to use contemporary AAA rupture rates to inform optimal size thresholds for AAA repair. METHODS: We used a Markov chain analysis to estimate life expectancy for patients with AAA. The primary outcome was AAA-related mortality. We estimated survival using Social Security Administration life tables and published contemporary AAA rupture estimates. For those undergoing repair, we modified survival estimates using data from the Vascular Quality Initiative and Medicare on complications, late rupture, and open conversion. We used this model to estimate the AAA repair size threshold that minimizes AAA-related mortality for 60-year-old average-health men and women. We performed a sensitivity analysis of poor-health patients and 70- and 80-year-old base cases. RESULTS: The annual risk of all-cause mortality under surveillance for a 60-year-old woman presenting with a 5.0 cm AAA using repair thresholds of 5.5 cm, 6.0 cm, 6.5 cm, and 7.0 cm was 1.7%, 2.3%, 2.7%, and 2.8%, respectively. The corresponding risk for a man was 2.3%, 2.9%, 3.3%, and 3.4% for the same repair thresholds, respectively. For a 60-year-old average-health woman, an AAA repair size of 6.1 cm was the optimal threshold to minimize AAA-related mortality. Life expectancy varied by <2 months for repair at sizes from 5.7 cm to 7.1 cm. For a 60-year-old average-health man, an AAA repair size of 6.9 cm was the optimal threshold to minimize AAA-related mortality. Life expectancy varied by <2 months for repair at sizes from 6.0 cm to 7.4 cm. Women in poor health, at various age strata, had optimal AAA repair size thresholds that were >6.5 cm, whereas men in poor health, at all ages, had optimal repair size thresholds that were >8.0 cm. CONCLUSIONS: The optimal threshold for AAA repair is more nuanced than a discrete size. Specifically, there appears to be a range of AAA sizes for which repair is reasonable to minmized AAA-related mortality. Notably, they all are greater than current guideline recommendations. These findings would suggest that contemporary AAA size thresholds for repair should be reconsidered.

A dedicated risk prediction model of 1-year mortality following endovascular aortic aneurysm repair involving the renal-mesenteric arteries.

OBJECTIVE: Treatment goals of prophylactic endovascular aortic repair of complex aneurysms involving the renal-mesenteric arteries (complex endovascular aortic repair [cEVAR]) include achieving both technical success and long-term survival benefit. Mortality within the first year after cEVAR likely indicates treatment failure owing to associated costs and procedural complexity. Notably, no validated clinical decision aid tools exist that reliably predict mortality after cEVAR. The purpose of this study was to derive and validate a preoperative prediction model of 1-year mortality after elective cEVAR. METHODS: All elective cEVARs including fenestrated, branched, and/or chimney procedures for aortic disease extent confined proximally to Ishimaru landing zones 6 to 9 in the Society for Vascular Surgery Vascular Quality Initiative were identified (January 2012 to August 2023). Patients (n = 4053) were randomly divided into training (n = 3039) and validation (n = 1014) datasets. A logistic regression model for 1-year mortality was created and internally validated by bootstrapping the AUC and calibration intercept and slope, and by using the model to predict 1-year mortality in the validation dataset. Independent predictors were assigned an integer score, based on model beta-coefficients, to generate a simplified scoring system to categorize patient risk. RESULTS: The overall crude 1-year mortality rate after elective cEVAR was 11.3% (n = 456/4053). Independent preoperative predictors of 1-year mortality included chronic obstructive pulmonary disease, chronic renal insufficiency (creatinine >1.8 mg/dL or dialysis dependence), hemoglobin <12 g/dL, decreasing body mass index, congestive heart failure, increasing age, American Society of Anesthesiologists class ≥IV, current tobacco use, history of peripheral vascular intervention, and increasing extent of aortic disease. The 1-year mortality rate varied from 4% among the 23% of patients classified as low risk to 23% for the 24% classified as high risk. Performance of the model in validation was comparable with performance in the training data. The internally validated scoring system classified patients roughly into quartiles of risk (low, low/medium, medium/high and high), with 52% of patients categorized as medium/high to high risk, which had corresponding 1-year mortality rates of 11% and 23%, respectively. Aneurysm diameter was below Society for Vascular Surgery recommended treatment thresholds (<5.0 cm in females, <5.5 cm in males) in 17% of patients (n = 679/3961), 41% of whom were categorized as medium/high or high risk. This subgroup had significantly increased in-hospital complication rates (18% vs 12%; P = .02) and 1-year mortality (13% vs 5%; P < .0001) compared with patients in the low- or low/medium-risk groups with guideline-compliant aneurysm diameters (≥5.0 cm in females, ≥5.5 cm in males). CONCLUSIONS: This validated preoperative prediction model for 1-year mortality after cEVAR incorporates physiological, functional, and anatomical variables. This novel and simplified scoring system can effectively discriminate mortality risk and, when applied prospectively, may facilitate improved preoperative decision-making, complex aneurysm care delivery, and resource allocation.

An international, expert-based, Delphi consensus document on controversial issues in the management of abdominal aortic aneurysms.

OBJECTIVE: As a result of conflicting, inadequate or controversial data in the literature, several issues concerning the management of patients with abdominal aortic aneurysms (AAAs) remain unanswered. The aim of this international, expert-based Delphi consensus document was to provide some guidance for clinicians on these controversial topics. METHODS: A three-round Delphi consensus document was produced with 44 experts on 6 prespecified topics regarding the management of AAAs. All answers were provided anonymously. The response rate for each round was 100%. RESULTS: Most participants (42 of 44 [95.4%]) agreed that a minimum case volume per year is essential (or probably essential) for a center to offer open or endovascular AAA repair (EVAR). Furthermore, 33 of 44 (75.0%) believed that AAA screening programs are (probably) still clinically effective and cost effective. Additionally, most panelists (36 of 44 [81.9%]) voted that surveillance after EVAR should be (or should probably be) lifelong. Finally, 35 of 44 participants (79.7%) thought that women smokers should (or should probably/possibly) be considered for screening at 65 years of age, similar to men. No consensus was achieved regarding lowering the threshold for AAA repair and the need for deep venous thrombosis prophylaxis in patients undergoing EVAR. CONCLUSIONS: This expert-based Delphi consensus document provides guidance for clinicians regarding specific unresolved issues. Consensus could not be achieved on some topics, highlighting the need for further research in those areas.

Role of Signal Degradation in Directional Chemosensing.

Directional chemosensing is ubiquitous in cell biology, but some cells such as mating yeast paradoxically degrade the signal they aim to detect. While the data processing inequality suggests that such signal modification cannot increase the sensory information, we show using a reaction-diffusion model and an exactly solvable discrete-state reduction that it can. We identify a non-Markovian step in the information chain allowing the system to evade the data processing inequality, reflecting the nonlocal nature of diffusion. Our results apply to any sensory system in which degradation couples to diffusion. Experimental data suggest that mating yeast operate in the beneficial regime where degradation improves sensing.

A Retrospective Analysis of Surgical Acuity & Procedure Volume Before & During the COVID-19 Pandemic.

INTRODUCTION: In March 2020, the American College of Surgeons recommended postponing elective procedures amid the COVID-19 pandemic. We used Medicare claims to analyze changes in surgical and interventional procedure volumes from 2016 to 2021. METHODS: We studied 37 common surgical and interventional procedures using 5% Medicare claims files from January 1, 2016, through December 31, 2021. Procedures were classified according to American College of Surgeons guidelines as low, intermediate, or high acuity, and counts were analyzed per calendar year quarter (Q1-Q4), with stratification by sex and race/ethnicity. RESULTS: We observed 1,840,577 procedures and identified two periods of marked decline. In Q2 2020, overall procedure counts decreased by 32.2%, with larger declines in low (41.1%) and intermediate (30.8%) acuity procedures. High acuity procedures declined the least (18.2%). Overall volumes increased afterward but never returned to baseline. Another marked decline occurred in Q4 2021, with all acuity levels having declined to a similar extent (40.1%, 44.2%, and 46.9% for low, intermediate, and high acuity, respectively). High and intermediate acuity procedures declined more in Q4 2021 than Q2 2020 (P = 0.002). Similar patterns were observed across sex and race/ethnicity strata. CONCLUSIONS: Two major procedural volume declines occurred between 2020 and 2022 during the COVID-19 pandemic in the United States. High acuity (life or limb threatening) procedures were least affected in the first decline (Q2 2020) but not spared in second decline (Q4 2021). Future efforts should prioritize preserving high-acuity access during times of stress.

Discovery of the first selective, small-molecule GFRα2/3 inhibitors through DNA-encoded library technology.

Studies have shown that disrupting the formation of the ligand-RET-GFRα complex could be an effective way of treating pain and itch. Compared to traditional high-throughput screens, DNA encoded libraries (DELs) have distinguished themselves as a powerful technology for hit identification in recent years. The present work demonstrates the use of DEL technology identifying compound 16 as the first GFRa2/GFRa3 small molecule inhibitor (0.1/0.2 µM respectively) selective over RET. This molecule represents an opportunity to advance the development of small-molecule inhibitors targeting the GFRα-RET interface for the treatment of pain and itch.

Most preoperative stress tests fail to comply with practice guideline indications and do not reduce cardiac events.

BACKGROUND: There is wide variation in stress test utilization before major vascular surgery and adherence to practice guidelines is unclear. We defined rates of stress test compliance at our institution and led a quality improvement initiative to improve compliance with American Heart Association (ACC/AHA) guidelines. METHODS: We implemented a stress testing order set in the electronic medical record at one tertiary hospital. We reviewed all patients who underwent elective, major vascular surgery in the 6 months before (Jan 1, 2022 - Jul 1, 2022) and 6 months after (Aug 1, 2022 - Jan 31, 2023) implementation. We studied stress test guideline compliance, changes in medical or surgical management, and major adverse cardiac events (MACE). RESULTS: Before order set implementation, 37/122 patients (30%) underwent stress testing within the past year (29 specifically ordered preoperatively) with 66% (19/29) guideline compliance. After order set implementation, 50/173 patients (29%) underwent stress testing within the past year (41 specifically ordered preoperatively) with 80% (33/41) guideline compliance. In the pre- and postimplementation cohorts, stress testing led to a cardiovascular medication change or preoperative coronary revascularization in 24% (7/29) and 27% (11/41) of patients, and a staged surgery or less invasive anesthetic strategy in 14% (4/29) and 4.9% (2/41) of patients, respectively. All unindicated stress tests were surgeon-ordered and none led to a change in management. There was no change in MACE after order set implementation. CONCLUSIONS: Electronic medical record-based guidance of perioperative stress testing led to a slight decrease in overall stress testing and an increase in guideline-compliant testing. Our study highlights a need for improved preoperative cardiovascular risk assessment prior to major vascular surgery, which may eliminate unnecessary testing and more effectively guide perioperative decision-making.

Duplex Ultrasound-Only Surveillance after Endovascular Abdominal Aortic Aneurysm Repair is Associated with Favorable Long-Term Outcomes.

BACKGROUND: Long-term data surrounding the impact of different endovascular abdominal aortic aneurysm repair (EVAR) surveillance strategies are limited. Therefore, the purpose of this study was to characterize postoperative imaging patterns, as well as to evaluate the association of duplex ultrasound surveillance after the first postoperative year with 5-year EVAR outcomes. METHODS: EVAR patients (2003-2016), who survived at least 1 year without aneurysm rupture, conversion to open repair, and reintervention in the Vascular Implant Surveillance and Interventional Outcomes Network were examined to provide all subjects ≥3 years of follow-up time. Patients were categorized into 6 cohorts after the first postoperative year: No imaging (N = 953); computed tomography (CT)/magnetic resonance imaging (MRI)-only (N = 2,976); duplex ultrasound-only (DUS; N = 1,808); combined CT/MRI + DUS with >50% being CT/MRI (N = 1,937); combined CT/MRI + DUS with >50% being DUS (N = 2,253); and mixed (CT + DUS + MRI N = 1,272). Abdominal aortic aneurysm (AAA)-related reintervention, rupture, conversion to open repair, and all-cause mortality were estimated using Kaplan-Meier analysis. Multivariable logistic regression models identified variables associated with using DUS-only imaging (versus CT/MRI only). Cox regression models compared 5-year outcomes between patients receiving DUS-only versus CT/MRI-only imaging. RESULTS: A total of 11,199 EVAR patients were examined (mean age 76 ± 7 years; female: 20%; nonelective: 10%). DUS-only imaging surveillance after the first postoperative year was more likely to occur after elective repairs, as well as among older, male patients. Smaller (<6 cm) preoperative AAA diameter and absence of documented concurrent iliac aneurysm was also associated with DUS-only follow-up. Additionally, no endoleak detection on index EVAR completion imaging, as well as a documented >5 mm decrease in AAA sac diameter at 1-year follow-up was more common with DUS-only surveillance protocols. Post-EVAR DUS-only imaging after the first postoperative year had the lowest incidence of reintervention, conversion to open repair, and rupture (as well as the composite reintervention/open conversion/rupture; log-rank P < 0.001 for all). Further, patients receiving exclusively DUS after their first postoperative year had better overall survival (log-rank P < 0.001). These outcome advantages that were associated with DUS-only surveillance compared with CT/MRI-only surveillance after EVAR persisted when controlling for baseline covariates, preoperative AAA diameter, prior aortic surgery history, sac growth, and presence of endoleak (all P < 0.01). CONCLUSIONS: EVAR patients selected for DUS-only surveillance after the first postoperative year have excellent freedom from AAA-related reintervention, conversion to open repair, rupture and all-cause mortality. These findings remained on multivariable analysis after adjusting for baseline characteristics, endoleak status and sac diameter changes within the first year. This is the first registry-based investigation to document long-term EVAR outcomes for patients entered into a DUS-only monitoring protocol which serves to corroborate the growing evidence base that DUS may be able to supplant CT surveillance in certain subgroups. A prospective randomized multicenter trial comparing DUS versus CT-based imaging after EVAR is needed to validate these findings which may serve to change current practice guidelines, as well as industry and regulatory stakeholder requirements.

The Sustained Impact of the COVID-19 Pandemic on Vascular Surgical Care Delivery.

BACKGROUND: The COVID-19 pandemic necessitated postponement of vascular surgery procedures nationally. Whether procedure volumes have since recovered remains undefined. Therefore, our objective was to quantify changes in procedure volumes and determine whether surgical volume has returned to its prepandemic baseline. METHODS: This study was a retrospective cross-sectional study between 2018 and 2023 using the US Fee-for-Service Medicare 5% National Sample as part of the VA Disrupted Care National Project. We studied patients who underwent 1 of 3 procedures: abdominal aortic aneurysm (AAA) repair for intact aneurysms, carotid endarterectomy (CEA), and major lower extremity amputation (LEA). The case volume of each quarter of 2020-2023 was compared to its corresponding prepandemic quarter in 2019. We then performed a subanalysis of these trends by sex, age, and race. RESULTS: We identified 21,031 procedures: 4,411 AAA repair, 8,361 CEA, and 8,259 LEA. The average percent change during the baseline prepandemic period from 2018 to 2019 was -4.3% for AAA repair, -8.5% for CEA, and -2.6% for LEA. Compared to Q2 of 2019, Q2 of 2020 demonstrated that AAA repair procedures decreased by 47%, CEA by 40%, and LEA by 14%. While procedures initially rebounded in Q3 of 2020, volumes did not return to their prepandemic baseline, demonstrating a persistent volume reduction (-16% AAA, -22% CEA, and -11% LEA). Thereafter, procedure counts again declined in Q1 of 2022 (-25% AAA, -34% CEA, and -25% LEA). CONCLUSIONS: Despite a perception that vascular surgical care was singularly disrupted at the outset of the pandemic, there has been a sustained reduction in vascular surgical volume since 2019. Not only have procedure volumes not returned to prepandemic baseline but it also appears that there has been a cumulative incremental impact on overall procedure volume. The impact of these findings on long-term population health remains uncertain and necessitates a better understanding of postpandemic care delivery.