High-coverage whole-genome sequencing of the expanded 1000 Genomes Project cohort including 602 trios.

The 1000 Genomes Project (1kGP) is the largest fully open resource of whole-genome sequencing (WGS) data consented for public distribution without access or use restrictions. The final, phase 3 release of the 1kGP included 2,504 unrelated samples from 26 populations and was based primarily on low-coverage WGS. Here, we present a high-coverage 3,202-sample WGS 1kGP resource, which now includes 602 complete trios, sequenced to a depth of 30X using Illumina. We performed single-nucleotide variant (SNV) and short insertion and deletion (INDEL) discovery and generated a comprehensive set of structural variants (SVs) by integrating multiple analytic methods through a machine learning model. We show gains in sensitivity and precision of variant calls compared to phase 3, especially among rare SNVs as well as INDELs and SVs spanning frequency spectrum. We also generated an improved reference imputation panel, making variants discovered here accessible for association studies.

A draft human pangenome reference.

Here the Human Pangenome Reference Consortium presents a first draft of the human pangenome reference. The pangenome contains 47 phased, diploid assemblies from a cohort of genetically diverse individuals1. These assemblies cover more than 99% of the expected sequence in each genome and are more than 99% accurate at the structural and base pair levels. Based on alignments of the assemblies, we generate a draft pangenome that captures known variants and haplotypes and reveals new alleles at structurally complex loci. We also add 119 million base pairs of euchromatic polymorphic sequences and 1,115 gene duplications relative to the existing reference GRCh38. Roughly 90 million of the additional base pairs are derived from structural variation. Using our draft pangenome to analyse short-read data reduced small variant discovery errors by 34% and increased the number of structural variants detected per haplotype by 104% compared with GRCh38-based workflows, which enabled the typing of the vast majority of structural variant alleles per sample.

Genetic control of the pluripotency epigenome determines differentiation bias in mouse embryonic stem cells.

Genetically diverse pluripotent stem cells display varied, heritable responses to differentiation cues. Here, we harnessed these disparities through derivation of mouse embryonic stem cells from the BXD genetic reference panel, along with C57BL/6J (B6) and DBA/2J (D2) parental strains, to identify loci regulating cell state transitions. Upon transition to formative pluripotency, B6 stem cells quickly dissolved naïve networks adopting gene expression modules indicative of neuroectoderm lineages, whereas D2 retained aspects of naïve pluripotency. Spontaneous formation of embryoid bodies identified divergent differentiation where B6 showed a propensity toward neuroectoderm and D2 toward definitive endoderm. Genetic mapping identified major trans-acting loci co-regulating chromatin accessibility and gene expression in both naïve and formative pluripotency. These loci distally modulated occupancy of pluripotency factors at hundreds of regulatory elements. One trans-acting locus on Chr 12 primarily impacted chromatin accessibility in embryonic stem cells, while in epiblast-like cells, the same locus subsequently influenced expression of genes enriched for neurogenesis, suggesting early chromatin priming. These results demonstrate genetically determined biases in lineage commitment and identify major regulators of the pluripotency epigenome.

Mapping and characterization of structural variation in 17,795 human genomes.

A key goal of whole-genome sequencing for studies of human genetics is to interrogate all forms of variation, including single-nucleotide variants, small insertion or deletion (indel) variants and structural variants. However, tools and resources for the study of structural variants have lagged behind those for smaller variants. Here we used a scalable pipeline1 to map and characterize structural variants in 17,795 deeply sequenced human genomes. We publicly release site-frequency data to create the largest, to our knowledge, whole-genome-sequencing-based structural variant resource so far. On average, individuals carry 2.9 rare structural variants that alter coding regions; these variants affect the dosage or structure of 4.2 genes and account for 4.0-11.2% of rare high-impact coding alleles. Using a computational model, we estimate that structural variants account for 17.2% of rare alleles genome-wide, with predicted deleterious effects that are equivalent to loss-of-function coding alleles; approximately 90% of such structural variants are noncoding deletions (mean 19.1 per genome). We report 158,991 ultra-rare structural variants and show that 2% of individuals carry ultra-rare megabase-scale structural variants, nearly half of which are balanced or complex rearrangements. Finally, we infer the dosage sensitivity of genes and noncoding elements, and reveal trends that relate to element class and conservation. This work will help to guide the analysis and interpretation of structural variants in the era of whole-genome sequencing.

Exome sequencing of Finnish isolates enhances rare-variant association power.

Exome-sequencing studies have generally been underpowered to identify deleterious alleles with a large effect on complex traits as such alleles are mostly rare. Because the population of northern and eastern Finland has expanded considerably and in isolation following a series of bottlenecks, individuals of these populations have numerous deleterious alleles at a relatively high frequency. Here, using exome sequencing of nearly 20,000 individuals from these regions, we investigate the role of rare coding variants in clinically relevant quantitative cardiometabolic traits. Exome-wide association studies for 64 quantitative traits identified 26 newly associated deleterious alleles. Of these 26 alleles, 19 are either unique to or more than 20 times more frequent in Finnish individuals than in other Europeans and show geographical clustering comparable to Mendelian disease mutations that are characteristic of the Finnish population. We estimate that sequencing studies of populations without this unique history would require hundreds of thousands to millions of participants to achieve comparable association power.

Author Correction: Exome sequencing of Finnish isolates enhances rare-variant association power.

An Amendment to this paper has been published and can be accessed via a link at the top of the paper.

Association of structural variation with cardiometabolic traits in Finns.

The contribution of genome structural variation (SV) to quantitative traits associated with cardiometabolic diseases remains largely unknown. Here, we present the results of a study examining genetic association between SVs and cardiometabolic traits in the Finnish population. We used sensitive methods to identify and genotype 129,166 high-confidence SVs from deep whole-genome sequencing (WGS) data of 4,848 individuals. We tested the 64,572 common and low-frequency SVs for association with 116 quantitative traits and tested candidate associations using exome sequencing and array genotype data from an additional 15,205 individuals. We discovered 31 genome-wide significant associations at 15 loci, including 2 loci at which SVs have strong phenotypic effects: (1) a deletion of the ALB promoter that is greatly enriched in the Finnish population and causes decreased serum albumin level in carriers (p = 1.47 × 10-54) and is also associated with increased levels of total cholesterol (p = 1.22 × 10-28) and 14 additional cholesterol-related traits, and (2) a multi-allelic copy number variant (CNV) at PDPR that is strongly associated with pyruvate (p = 4.81 × 10-21) and alanine (p = 6.14 × 10-12) levels and resides within a structurally complex genomic region that has accumulated many rearrangements over evolutionary time. We also confirmed six previously reported associations, including five led by stronger signals in single nucleotide variants (SNVs) and one linking recurrent HP gene deletion and cholesterol levels (p = 6.24 × 10-10), which was also found to be strongly associated with increased glycoprotein level (p = 3.53 × 10-35). Our study confirms that integrating SVs in trait-mapping studies will expand our knowledge of genetic factors underlying disease risk.

Early outcomes of endovascular repairs of the aortic arch using thoracic branch endoprosthesis.

OBJECTIVE: The only commercially available thoracic branched endoprosthesis (TBE) for treatment of the aortic arch was released in 2022. Limited data outside of clinical trial results have been reported. This study describes the demographics, anatomic details, and outcomes for patients treated for zone 0 to 2 using TBEs outside of a clinical trial. METHODS: All patients treated using TBEs for zone 0 to 2 were included. Patients treated as part of the clinical trial for zone 0 to 1 (n = 6) were excluded. Patient demographics, comorbidities, anatomic and operative details, and outcomes were reported. Outcomes and survival were then compared between groups. RESULTS: Of 40 patients, six patients underwent repair of zone 0, three of zone 1, and 31 of zone 2. There were no differences in demographics, comorbidities, or operative details by zone of treatment; however, the frequency of genetic aortopathy differed (zone 0: 0%; zone 1: 67%; and zone 2: 6.4%; P < .01). Seventy-three percent of patients were treated for dissection vs 27% with isolated aneurysms. Of the patients, 2.5% were treated for rupture, 22% were treated for symptomatic aneurysms, and 75% were treated electively. Forty-eight percent of repairs included a proximal cuff, and 83% received distal extension. Technical success was achieved in 100% of patients. Mean fluoroscopy time was 18 minutes, and median fluoroscopy dose was 416 mGy. Sixty percent of patients had prior aortic ascending/arch repair. TBE was planned as part of a complete thoracoabdominal repair in 45% of patients. Thirty-day mortality was 2.5% overall, with a single death in a zone 0 patient that occurred at day 1 due to a myocardial infarction. There were no reinterventions within 30 days. All other outcomes were similar. The 30-day stroke rate was 5.0%. The strokes occurred at day 6 (zone 1) and day 15 (zone 2); however, both were due to occlusion of a prior proximal surgical bypass and unrelated to the TBE side branch or embolization. Specifically, both patients had occlusion of a branch of their prior zone 1 or zone 2 arch replacement. An endoleak occurred in 7.5% of patients at 30-day follow-up (type II: 5.0%; unknown: 2.5%). At a mean follow-up of 6.6 months, 100% of side branches were patent. CONCLUSIONS: Repair of the aortic arch including TBE can be performed electively and urgently with acceptable stroke and death rates. TBE provides a valuable tool for patients requiring complete repair of a thoracoabdominal aneurysm. Continued investigation is underway to assess long-term safety and efficacy outside of the clinical trial.

Hemorrhage at high altitude: impact of sustained hypobaric hypoxia on cerebral blood flow, tissue oxygenation, and tolerance to simulated hemorrhage in humans.

With ascent to high altitude (HA), compensatory increases in cerebral blood flow and oxygen delivery must occur to preserve cerebral metabolism and consciousness. We hypothesized that this compensation in cerebral blood flow and oxygen delivery preserves tolerance to simulated hemorrhage (via lower body negative pressure, LBNP), such that tolerance is similar during sustained exposure to HA vs. low altitude (LA). Healthy humans (4F/4 M) participated in LBNP protocols to presyncope at LA (1130 m) and 5-7 days following ascent to HA (3800 m). Internal carotid artery (ICA) blood flow, cerebral delivery of oxygen (CDO2) through the ICA, and cerebral tissue oxygen saturation (ScO2) were determined. LBNP tolerance was similar between conditions (LA: 1276 ± 304 s vs. HA: 1208 ± 306 s; P = 0.58). Overall, ICA blood flow and CDO2 were elevated at HA vs. LA (P ≤ 0.01) and decreased with LBNP under both conditions (P < 0.0001), but there was no effect of altitude on ScO2 responses (P = 0.59). Thus, sustained exposure to hypobaric hypoxia did not negatively impact tolerance to simulated hemorrhage. These data demonstrate the robustness of compensatory physiological mechanisms that preserve human cerebral blood flow and oxygen delivery during sustained hypoxia, ensuring cerebral tissue metabolism and neuronal function is maintained.

If we know better, why don't we do better? A rapid quality improvement project to increase utilization of comfort measures to reduce pain and distress in children in a COVID-19 mass vaccination clinic.

INTRODUCTION: Many evidence-based tools exist to address pain and distress associated with injections; however, there remains a large gap between the knowledge of these tools and their utilization. Our hospital began a quality improvement (QI) project prior to COVID-19, with the goal of increasing the utilization of Comfort Promise measures during needle procedures. When COVID-19 vaccinations were approved, our mass vaccination clinics provided an opportunity to rapidly increase utilization across the institution. The primary aim was to increase the percentage of comfort measures (CM) offered with COVID-19 vaccinations. METHODS: Through this QI project, nurses and other professionals implemented CMs during COVID mass vaccination clinics. Clinics occurred in 3 age-based waves. Waves served as Plan-Do-Study-Act (PDSA) cycles. Families completed post-vaccination surveys to determine what CMs were offered and intention for future use with vaccinations. RESULTS: Uptake of CMs (PainEase, ShotBlockers, Comfort Positioning, Alternative Focus, Topical Lidocaine, and Breastfeeding/Sucrose) throughout the waves increased and generally remained stable. CMs also seemed to decrease pain/distress with vaccinations (70.5 to 88.7%), and children/caregivers intended to use some combination for future vaccinations (82.5 to 98.5%). CONCLUSIONS: Fast-paced mass vaccination clinics provided an ideal opportunity to significantly increase utilization of CMs. Across age groups CMs yielded high satisfaction and interest in future utilization. Clinic nurses returned to their own sub-specialties and became change agents. IMPLICATIONS: If all healthcare providers can work together to achieve consensus while incorporating comfort measures into daily practice, sustained change with incorporation of these evidence-based tools can be achieved. Future directions are discussed.

Retrospective Evaluation of Melphalan, Vincristine, and Cytarabine Chemotherapy for the Treatment of Relapsed Canine Lymphoma.

Dogs diagnosed with multicentric lymphoma often relapse following induction therapy within the first year of treatment. The primary aim of this study was to evaluate the tolerability of a novel drug combination using melphalan, vincristine, and cytarabine (MOC) for the treatment of relapsed lymphoma. On day 1, dogs were treated with vincristine (0.5-0.6 mg/m2 IV) and cytarabine (300 mg/m2 IV over 4-6 hr or subcutaneously over 2 days). On day 7, dogs were treated with melphalan (20 mg/m2per os). This 2 wk protocol was repeated for at least three cycles or until treatment failure. Twenty-six dogs were treated with MOC and met the inclusion criteria. Twenty-three dogs had toxicity data, and all experienced adverse events with the majority graded as mild. The overall response rate was 38%, which included 19% of dogs who achieved a complete response. The median progression-free survival was 29 days (range 1-280 days). The overall clinical benefit was 65% for a median of 37 days (range 33-280 days). MOC is a safe treatment option for relapsed lymphoma in dogs.

Polysilaketals: High-Performance Polyether-Based Electrolytes with Tunable Disubstituted Silane Linkers.

Polymer electrolytes exhibit higher energy density and improved safety in lithium-ion batteries relative to traditionally used liquid electrolytes but are currently limited by their lower electrochemical performance. Aiming to access polymer electrolytes with competitive electrochemical properties, we developed the anionic ring-opening polymerization (AROP) of cyclic silaketals to synthesize amorphous silicon-containing polyether-based electrolytes with varying substituent bulk of the general formula [OSi(R)2(CH2CH2O)2]n (R = alkyl, phenyl). As opposed to previously reported uncontrolled polycondensation routes toward low molecular weight polysilaketals, AROP allows access to targeted molecular weights above the entanglement threshold of the polymers. The polysilaketal with the lowest steric bulk (P(OSiMe,Me-2EO)) exceeds the conductivity of poly(ethylene oxide) (PEO), a leading polymer electrolyte. To the best of our knowledge, this is the first solid polymer electrolyte to achieve this benchmark. Steric bulk in polysilaketals was found to impart stability and two bulkier polysilaketals, P(OSiEt,Et-2EO) and P(OSiMe,Ph-2EO), exhibited higher current fractions than PEO over a wide range of salt loadings. Moreover, the efficacy of P(OSiEt,Et-2EO) was competitive with that of PEO. Taken together, the tunable and competitive electrochemical properties of polysilaketals validate the  systematic incorporation of silyl groups as a strategy to access high performance polymer electrolytes.

Advancements in Novel Live Biotherapeutic Products for Clostridioides difficile Infection Prevention.

The profound impact of the human microbiome on health and disease has captivated the interest of clinical and scientific communities. The human body hosts a vast array of microorganisms collectively forming the human microbiome, which significantly influences various physiological processes and profoundly shapes overall well-being. Notably, the gut stands out as an exceptional reservoir, harboring the most significant concentration of microorganisms, akin to an organ in itself. The gut microbiome's composition and function are influenced by genetics, environment, age, underlying conditions, and antibiotic usage, leading to dysbiosis and pathogenesis, such as Clostridioides difficile infection (CDI). Conventional CDI treatment, involving antibiotics like oral vancomycin and fidaxomicin, fails to address dysbiosis and may further disrupt gut microbial communities. Consequently, emerging therapeutic strategies are focused on targeting dysbiosis and restoring gut microbiota to advance CDI therapeutics. Fecal microbiota transplantation (FMT) has demonstrated remarkable efficacy in treating recurrent CDI by transferring processed stool from a healthy donor to a recipient, restoring gut dysbiosis and enhancing bacterial diversity. Moreover, 2 newer Food and Drug Administration (FDA)-approved live biotherapeutic products (LBP), namely, Fecal Microbiota Live-JSLM and Fecal Microbiota Spores Live-BRPK, have shown promise in preventing CDI recurrence. This review explores the role of the gut microbiota in preventing and treating CDI, with an emphasis on gut-based interventions like FMT and fecal microbiota-based products that hold potential for gut restoration and prevention of CDI recurrence. Understanding the microbiome's impact on CDI prevention and treatment offers valuable insights for advancing future CDI therapeutics.

Fighting the obesity pandemic during the COVID-19 pandemic.

BACKGROUND: The COVID-19 pandemic created delays in surgical care. The population with obesity has a high risk of death from COVID-19. Prior literature shows the most effective way to combat obesity is by weight loss surgery. At different times throughout the COVID-19 pandemic, elective inpatient surgeries have been halted due to bed availability. Recognizing that major complications following bariatric surgery are extremely low (bleeding 0-4%, anastomotic leaks 0.8%), we felt outpatient bariatric surgery would be safe for low-risk patients. Complications such as DVT, PE, infection, and anastomotic leaks typically present after 7 days postoperatively, well outside the usual length of stay. Bleeding events, severe postoperative nausea, and dehydration typically occur in the first few days postoperatively. We designed a pathway focused on detecting and preventing these early post-op complications to allow safe outpatient bariatric surgery. METHODS: We used a preoperative evaluation tool to risk stratify bariatric patients. During a 16-month period, 89 patients were identified as low risk for outpatient surgery. We designed a postoperative protocol that included IV hydration and PO intake goals to meet a safe discharge. We sent patients home with a pulse oximeter and had them self-monitor their pulse and oxygen saturation. We called all patients at 10 pm for a postoperative assessment and report of their vitals. Patients returned to clinic the following day and were seen by a provider, received IV hydration, and labs were drawn. RESULTS: 80 of 89 patients (89.8%) were successfully discharged on POD 0. 3 patients were readmitted within 30 days. We had zero deaths in our study cohort and no morbidity that would have been prevented with postoperative admission. CONCLUSION: We demonstrate that by identifying low-risk patients for outpatient bariatric surgery and by implementing remote monitoring of vitals early outpatient follow-up, we were able to safely perform outpatient bariatric surgery.

Student pharmacists delivering academic detailing on adult pneumococcal vaccination to community pharmacists.

BACKGROUND: Academic detailing is an educational outreach approach to disseminate evidence-based information to health care professionals and improve clinical decision making. Pharmacists and physicians are recognized as the most qualified individuals to perform academic detailing; however, trained student pharmacists may also serve as suitable academic detailers. OBJECTIVES: To describe our academic detailing intervention that used trained student pharmacists to disseminate an updated pneumococcal vaccination clinical pathway (i.e., decision-support tool) and education to community pharmacists in Rhode Island and Massachusetts. METHODS: We updated an academic detailing initiative that included a pneumococcal vaccination clinical pathway and education for community pharmacists in 2021. Two University of Rhode Island (URI) College of Pharmacy pharmacist faculty members trained 6 student pharmacists to perform academic detailing. Student pharmacists visited URI-affiliated community pharmacies throughout Rhode Island and Massachusetts. After each session, each participant received a 6-question anonymous paper survey to assess the effectiveness of the updated pathway and academic detailing session. The survey used a 5-point Likert-type scale. We assessed the percentage agreement with each question. RESULTS: Academic detailing was delivered to 76 community pharmacists from May to August 2021. Most respondents agreed (89.2%, 58/65) that their knowledge of which patient populations met eligibility for the pneumococcal conjugate vaccine or pneumococcal polysaccharide vaccine improved. Respondents were confident they could apply the knowledge gained (93.8%, 61/65) and intended to apply the pathway (93.8%, 61/65) to clinical practice. Most respondents expected vaccination practices to change because of the academic detailing and education materials received (83.6%, 51/61). Almost all respondents (95.4%, 62/65) found the educational materials easy to understand. CONCLUSION: Trained student pharmacists can deliver academic detailing regarding adult pneumococcal vaccination to community pharmacists. Enlisting the help of student pharmacists may be a sustainable approach to academic detailing and provides students with valuable opportunities to practice delivering educational outreach to community pharmacists.

Pediatric Tube Weaning: A Meta-Analysis of Factors Contributing to Success.

Approximately 3-10% of children have severe feeding issues, and some require enteral/tube nutrition to grow and thrive. For many children, tube feeding is temporary, making efficacious interventions for tube weaning essential. We conducted a systematic review and meta-analysis of tube weaning treatments. Outcomes included percentage of participants completely weaned from the tube, and mean percentage of kilocalories consumed orally following treatment. Data were extracted from 42 studies, including cohort studies and single-subject research design studies. We evaluated moderators of treatment success, including treatment setting, use of behavioral approaches, use of hunger provocation, and use of a multidisciplinary approach. Results indicated that, after treatment, children received significantly more calories orally, and 67-69% of children were fully weaned. These analyses suggest that current interventions are generally effective; however, variability within treatments exist. Prospective randomized clinical trials are needed to understand effective components of weaning interventions.

Treatment, Clinical Outcomes, and Predictors of Mortality among a National Cohort of Admitted Patients with Acinetobacter baumannii Infection.

The objectives were to analyze treatment, clinical outcomes, and predictors of mortality in hospitalized patients with Acinetobacter baumannii infection. This was a retrospective cohort study of inpatients with A. baumannii cultures and treatment from 2010 to 2019. Patients who died during admission were compared to those who survived, to identify predictors of inpatient mortality, using multivariable unconditional logistic regression models. We identified 4,599 inpatients with A. baumannii infection; 13.6% died during admission. Fluoroquinolones (26.8%), piperacillin-tazobactam (24%), and carbapenems (15.6%) were used for treatment. Tigecycline (3%) and polymyxins (3.7%) were not used often. Predictors of inpatient mortality included current acute respiratory failure (adjusted odds ratio [aOR] 3.94), shock (aOR 3.05), and acute renal failure (aOR 2.01); blood (aOR 1.94) and respiratory (aOR 1.64) infectious source; multidrug-resistant A. baumannii (MDRAB) infection (aOR 1.66); liver disease (aOR 2.15); and inadequate initial treatment (aOR 1.30). Inpatient mortality was higher in those with MDRAB versus non-MDRAB (aOR 1.61) and in those with CRAB versus non-CRAB infection (aOR 1.68). Length of stay >10 days was higher among those with MDRAB versus non-MDRAB (aOR 1.25) and in those with CRAB versus non-CRAB infection (aOR 1.31). In our national cohort of inpatients with A. baumannii infection, clinical outcomes were worse among those with MDRAB and/or CRAB infection. Predictors of inpatient mortality included several current conditions associated with severity, infectious source, underlying illness, and inappropriate treatment. Our study may assist health care providers in the early identification of admitted patients with A. baumannii infection who are at higher risk of death.

Impact of Clopidogrel on Clinical Outcomes in Patients with Staphylococcus aureus Bacteremia: a National Retrospective Cohort Study.

Activated platelets have known antimicrobial activity against Staphylococcus aureus. Accelerated clearance of platelets induced by S. aureus can result in thrombocytopenia and increased mortality in patients. Recent studies suggest that P2Y12 inhibition protects platelets from accelerated clearance. We therefore evaluated the effect of P2Y12 inhibition on clinical outcomes in patients with S. aureus bacteremia across a large national cohort. Our retrospective cohort (2010 to 2018) included patients admitted to Veterans Affairs (VA) hospitals with blood cultures positive for S. aureus and treated with standard-of-care antibiotics. Employing propensity score-matched Cox proportional hazards regression models, we compared clinical outcomes in patients treated with clopidogrel for at least the 30 days prior to admission and continuing for at least 5 days after admission to patients without any P2Y12 inhibitor use in the year preceding admission. Mortality was significantly lower among clopidogrel users than P2Y12 inhibitor nonusers (n = 147 propensity score-matched pairs): the inpatient mortality hazard ratio (HR) was 0.11 (95% confidence interval [CI], 0.01 to 0.86), and 30-day mortality HR was 0.43 (95% CI, 0.19 to 0.98). There were no differences in 30-day readmission, 30-day S. aureus reinfection, microbiological clearance, or thrombocytopenia. Clopidogrel use at the time of infection reduced in-hospital mortality by 89% and 30-day mortality by 57% among a cohort of patients with S. aureus bacteremia. These results support the need to further study the use of P2Y12 inhibitors as adjunctive therapy in S. aureus bloodstream infections.

Relating individual differences in the reinforcing value of smoking and dependence severity to nicotine exposure levels in vulnerable populations.

Cigarette smoking is overrepresented in populations with psychiatric conditions and socioeconomic disadvantage. Greater understanding of the role of reinforcement and nicotine dependence in smoking among vulnerable populations may facilitate development of better targeted interventions to reduce smoking. Prior research demonstrated that individual differences in the reinforcing value of smoking and nicotine-dependence severity predicted total nicotine-exposure in vulnerable populations. The present study uses multivariate regression to address two aims: (1) Quantify the degree to which the reinforcing value of smoking, assessed using the Cigarette Purchase Task (CPT), and dependence severity assessed using the Fagerström Test of Nicotine Dependence and Brief Wisconsin Inventory of Smoking Dependence Motives (B-WISDM) each account for individual differences in cotinine-plus-3'-hydroxycotinine (COT+3HC) levels. (2) Explore whether there is overlap in the variance accounted for by the CTP, FTND, and B-WISDM. Participants were 628 adults with co-morbid psychiatric conditions or socioeconomic disadvantage who smoked daily. The CPT, FTND, and B-WISDM models accounted for 23.76%, 32.45%, and 29.61% of the variance in COT+3HC levels, respectively. Adding CPT to the FTND model failed to increase the variance accounted for and adding it to the B-WISDM model did so by only 1.2% demonstrating considerable overlap in the variance in nicotine exposure levels accounted for by these three instruments. These results provide new knowledge on the relationship between individual differences in the reinforcing value of smoking and nicotine-exposure levels and suggest differences in reinforcing value may underpin a considerable portion of the variance in nicotine exposure accounted for by dependence severity.

Comprehensive Ex Vivo Comparison of 5 Clinically Used Conduit Configurations for Valve-Sparing Aortic Root Replacement Using a 3-Dimensional-Printed Heart Simulator.

BACKGROUND: Many graft configurations are clinically used for valve-sparing aortic root replacement, some specifically focused on recapitulating neosinus geometry. However, the specific impact of such neosinuses on valvular and root biomechanics and the potential influence on long-term durability are unknown. METHODS: Using a custom 3-dimenstional-printed heart simulator with porcine aortic roots (n=5), the anticommissural plication, Stanford modification, straight graft (SG), Uni-Graft, and Valsalva graft configurations were tested in series using an incomplete counterbalanced measures design, with the native root as a control, to mitigate ordering effects. Hemodynamic and videometric data were analyzed using linear models with conduit as the fixed effect of interest and valve as a fixed nuisance effect with post hoc pairwise testing using Tukey's correction. RESULTS: Hemodynamics were clinically similar between grafts and control aortic roots. Regurgitant fraction varied between grafts, with SG and Uni-Graft groups having the lowest regurgitant fractions and anticommissural plication having the highest. Root distensibility was significantly lower in SG versus both control roots and all other grafts aside from the Stanford modification (P≤0.01 for each). All grafts except SG had significantly higher cusp opening velocities versus native roots (P<0.01 for each). Relative cusp opening forces were similar between SG, Uni-Graft, and control groups, whereas anticommissural plication, Stanford modification, and Valsalva grafts had significantly higher opening forces versus controls (P<0.01). Cusp closing velocities were similar between native roots and the SG group, and were significantly lower than observed in the other conduits (P≤0.01 for each). Only SG and Uni-Graft groups experienced relative cusp closing forces approaching that of the native root, whereas relative forces were >5-fold higher in the anticommissural plication, Stanford modification, and Valsalva graft groups. CONCLUSIONS: In this ex vivo modeling system, clinically used valve-sparing aortic root replacement conduit configurations have comparable hemodynamics but differ in biomechanical performance, with the straight graft most closely recapitulating native aortic root biomechanics.