Contrastive learning for enhancing feature extraction in anticancer peptides

Cancer, recognized as a primary cause of death worldwide, has profound health implications and incurs a substantial social burden. Numerous efforts have been made to develop cancer treatments, among which anticancer peptides (ACPs) are garnering recognition for their potential applications. While ACP screening is time-consuming and costly, in silico prediction tools provide a way to overcome these challenges. Herein, we present a deep learning model designed to screen ACPs using peptide sequences only. A contrastive learning technique was applied to enhance model performance, yielding better results than a model trained solely on binary classification loss. Furthermore, two independent encoders were employed as a replacement for data augmentation, a technique commonly used in contrastive learning. Our model achieved superior performance on five of six benchmark datasets against previous state-of-the-art models. As prediction tools advance, the potential in peptide-based cancer therapeutics increases, promising a brighter future for oncology research and patient care.

Soli-enabled noncontact heart rate detection for sleep and meditation tracking

Heart rate (HR) is a crucial physiological signal that can be used to monitor health and fitness. Traditional methods for measuring HR require wearable devices, which can be inconvenient or uncomfortable, especially during sleep and meditation. Noncontact HR detection methods employing microwave radar can be a promising alternative. However, the existing approaches in the literature usually use high-gain antennas and require the sensor to face the user's chest or back, making them difficult to integrate into a portable device and unsuitable for sleep and meditation tracking applications. This study presents a novel approach for noncontact HR detection using a miniaturized Soli radar chip embedded in a portable device (Google Nest Hub). The chip has a [Formula: see text] dimension and can be easily integrated into various devices. The proposed approach utilizes advanced signal processing and machine learning techniques to extract HRs from radar signals. The approach is validated on a sleep dataset (62 users, 498 h) and a meditation dataset (114 users, 1131 min). The approach achieves a mean absolute error (MAE) of 1.69 bpm and a mean absolute percentage error (MAPE) of [Formula: see text] on the sleep dataset. On the meditation dataset, the approach achieves an MAE of 1.05 bpm and a MAPE of [Formula: see text]. The recall rates for the two datasets are [Formula: see text] and [Formula: see text], respectively. This study represents the first application of the noncontact HR detection technology to sleep and meditation tracking, offering a promising alternative to wearable devices for HR monitoring during sleep and meditation.

Quantitative and Qualitative Impact of CT-Based Radiotherapy Dose Maps on Radiologists' Interpretation of Post-treatment Thoracic Surveillance Imaging

PURPOSE/OBJECTIVE(S)

For diagnostic radiologists, interpretation of surveillance imaging for oncology patients treated with radiation therapy (RT) can be challenging because (1) the imaging order may not adequately describe the radiation fields and (2) RT treatment effect and progression can appear similar. Volumetric dose visualization used for plan review is often inaccessible to radiologists. We hypothesize that displaying RT dose would improve radiologists' confidence and ability to correctly identify and distinguish irradiated targets and treatment effects.

MATERIALS/METHODS

CT images were read by a board-certified cardiothoracic radiologist and a diagnostic radiology resident. The readers interpreted pre-RT, treatment planning, and 3-4 month post-RT CT images in anonymized software sessions first without, then-after a 1 month "washout" period-with access to RT dose overlay. Six color-coded isodose lines ranging from 25% to 110% represented in absolute cGy were displayed along with a brief clinical history. RT fractionation schedules ranged in BED10 from 39 to 112.5 Gy. Readers were asked to label the treated lesion(s) and treatment effect(s), and record their confidence using a Likert scale of 1-5 and agreement with statements using yes/no responses.

RESULTS

Two readersindependently interpreted imaging for 32 patients who received thoracic RT to 1-5 lesion(s) for primary (24) or metastatic (8) cancer. Nineteen patients had 1 lesion and 13 patients had >1 lesion. Correct identification of all treated lesions significantly increased with the addition of dose visualization (61% to 81%; McNemar test, p = 0.00079), with the largest increase noted for cases with >1 lesion (15% to 54%; McNemar test, p = 0.0039). With the addition of dose information, the number of false negatives attributable to missed extranodal targets fell from 52% to 18%. Without dose information, 13% of labeled lesions and treatment effects fell outside of the 25% isodose lines, representing false positives. With the addition of dose information, false positives fell below 2% for both lesions and treatment effects. The readers' confidence that they had identified treated lesion(s) increased from a rating of 4.1 to 4.8 on a scale of 1-5 (Paired two-tail t test; p = 0.000005).

CONCLUSION

Whendiagnostic radiologists have access to dose visualization, correct identification rate of irradiated lesions and treatment effects, as well as confidence in these identifications significantly increased. The decrease in false negatives could reduce potential missed identification of tumor progression while the decrease in false positives could reduce inaccurate identification of treatment failure in a new or stable lesion. Our results demonstrate that adding volumetric visualization of dose to imaging could improve quality of surveillance care for patients with irradiated thoracic malignancies.

Critical transition and reversion of tumorigenesis

Cancer is caused by the accumulation of genetic alterations and therefore has been historically considered to be irreversible. Intriguingly, several studies have reported that cancer cells can be reversed to be normal cells under certain circumstances. Despite these experimental observations, conceptual and theoretical frameworks that explain these phenomena and enable their exploration in a systematic way are lacking. In this review, we provide an overview of cancer reversion studies and describe recent advancements in systems biological approaches based on attractor landscape analysis. We suggest that the critical transition in tumorigenesis is an important clue for achieving cancer reversion. During tumorigenesis, a critical transition may occur at a tipping point, where cells undergo abrupt changes and reach a new equilibrium state that is determined by complex intracellular regulatory events. We introduce a conceptual framework based on attractor landscapes through which we can investigate the critical transition in tumorigenesis and induce its reversion by combining intracellular molecular perturbation and extracellular signaling controls. Finally, we present a cancer reversion therapy approach that may be a paradigm-changing alternative to current cancer cell-killing therapies.

Association of Pre- and Post-Donation Renal Function with Midterm Estimated Glomerular Filtration Rate in Living Kidney Donors: A Retrospective Study

PURPOSE

The estimated glomerular filtration rate (eGFR) at 6 months after donation (eGFR_6m) is strongly associated with the risk of end-stage renal disease in living kidney donors. This study aimed to investigate the incidence of eGFR_6m <60 mL/min/1.73 m² (eGFR_6m <60) and identify the risk factors that can predict the occurrence of eGFR_6m <60 in living kidney donors.

MATERIALS AND METHODS

Living kidney donors who underwent nephrectomy at Severance Hospital between January 2009 and December 2019 were identified. We excluded 94 of 1233 donors whose creatinine values at 6 months after donation were missing. The risk factors for eGFR_6m <60 were assessed using multivariate regression analysis. The optimal cutoff points for candidate risk factors for predicting eGFR_6m <60 occurrence were determined using the Youden index.

RESULTS

The eGFR_6m <60 occurred in 17.3% of the participants. Older age (≥44 years), history of hypertension, lower preoperative eGFR (<101 mL/min/1.73 m²), and degree of increase in creatinine levels on postoperative day 2 compared to those before surgery (ΔCr2_pre) (≥0.39 mg/dL) increased the risk of eGFR_6m <60. The addition of ΔCr2_pre to preoperative eGFR yielded a higher predictive accuracy for predicting eGFR_6m <60 than that with preoperative eGFR alone {area under the receiver operating characteristic curve=0.886 [95% confidence interval (CI), 0.863-0.908] vs. 0.862 (95% CI, 0.838-0.887), p<0.001}.

CONCLUSION

The incidence of eGFR_6m <60 was 17.3%. Older age, lower preoperative eGFR, history of hypertension, and greater ΔCr2_pre were associated with the occurrence of eGFR_6m <60 after living donor nephrectomy. The combination of preoperative eGFR and ΔCr2_pre showed the highest predictive power for eGFR_6m <60.

Outer retinal degeneration in a non-human primate model using temporary intravitreal tamponade with N-methyl-N-nitrosourea in cynomolgus monkeys

Objective:The main objective of this study was to induce and evaluate drug-dose-dependent outer retinal degeneration in cynomolgus monkeys by application of N-methyl-N-nitrosourea (MNU).Approach:Intravitreal temporary tamponade induced outer retinal degeneration with MNU solutions (2-3 mg ml^-1) after vitrectomy in five cynomolgus monkeys. Optical coherence tomography (OCT), fundus autofluorescence (FAF), full-field electroretinography (ffERG), and visual evoked potentials (VEP) were performed at baseline and weeks 2, 6, and 12 postoperatively. At week 12, OCT angiography, histology, and immunohistochemistry were performed.Main results:Outer retinal degeneration was observed in four monkeys, especially in the peripheral retina. Anatomical and functional changes occurred at week 2 and persisted until week 12. FAF images showed hypoautofluorescence dots, similar to AF patterns seen in human retinitis pigmentosa. Hyperautofluorescent lesions in the pericentral area were also observed, which corresponded to the loss of the ellipsoid zone on OCT images. OCT revealed thinning of the outer retinal layer adding to the loss of the ellipsoid zone outside the vascular arcade. Histological findings confirmed that the abovementioned changes resulted from a gradual loss of photoreceptors from the perifovea to the peripheral retina. In contrast, the inner retina, including ganglion cell layers, was preserved. Functionally, a decrease or extinction of scotopic ffERGs was observed, which indicated rod-dominant loss. Nevertheless, VEPs were relatively preserved.Significance:Therefore, we can conclude that temporary exposure to intravitreal MNU tamponade after vitrectomy induces rod-dominant outer retinal degeneration in cynomolgus monkeys, especially in the peripheral retina.

Prevalence of modifiable risk factors and related poor cardiovascular outcomes following atrial fibrillation ablation

Background

Atrial fibrillation (AF) has become a global epidemic. Early catheter ablation and therapies modifying risk factors (RF) have been shown to improve outcomes of AF ablation. However, the time invested in pursuing risk factor modification may delay ablation, which could negate the procedural benefit.

Purpose

This study sought to investigate the prevalence and impact of potentially modifiable RF among AF patients undergoing catheter ablation in clinical practice.

Methods

This retrospective study included 724 consecutive patients undergoing AF ablation at a tertiary care center from 2012–2019. Pre-specified modifiable risks were examined, including the time from AF diagnosis to ablation, fluctuation/increase in BMI &gt;5% prior to ablation, mean systolic/diastolic blood pressure &gt;125/80 mmHg, obstructive sleep apnea with CPAP noncompliance, hyperlipidemia without statin therapy, tobacco use, excessive alcohol use, and diabetes mellitus with hemoglobin A1c (HbA1c) &gt;6.5%. The primary outcome was a composite of recurrent atrial arrhythmias, cardiovascular (CV) hospitalizations and mortality following AF ablation. A multivariate analysis was performed.

Results

The mean age was 61±10 years old, 32.5% were female and 72.2% had persistent AF. Many study patients had modifiable RF, ranging from 4.7% with excessive alcohol use to 64.0% experiencing delayed AF ablation. The mean time from AF diagnosis to ablation was 4.7 years. During a mean follow-up of 1.6 years after ablation, 467 (64.5%) patients met the primary outcome. Independent RF for the primary outcome were an increase/fluctuation in BMI &gt;5% (adjusted hazard ratio [AHR] 1.31, 95% confidence interval [CI] 1.07–1.60; P=0.008), diabetes with HbA1c &gt;6.5% (AHR 1.50, 95% CI 1.09–2.03; P=0.014) and hyperlipidemia without statin therapy (AHR 1.30, 95% CI 1.08–1.57; P=0.005). Delayed AF ablation over 1.5 years did not alter the outcome, Figure 1.

Conclusion

Substantial portions of patients undergoing AF ablation have potentially modifiable RF. Increased or fluctuating BMI, diabetes with HbA1c &gt;6.5%, and hyperlipidemia not treated with statin therapy portend an increased risk of recurrent atrial arrhythmia, CV hospitalizations and mortality. These findings underscore an importance pursuing RF management in patients with AF to reduce adverse outcomes after ablation.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): The Jensen Family Research Sponsorship at the University of Nebraska Medical Center

Ethmoidal and maxillary nerve block versus systemic opioid administration during rhinoscopy in dogs: a non-randomised clinical trial

OBJECTIVES

This study aimed to evaluate the clinical effects of ethmoidal and maxillary nerve blocks during rhinoscopy in dogs.

MATERIALS AND METHODS

Fourteen dogs underwent rhinoscopy. Under general anaesthesia with isoflurane, ethmoidal and maxillary nerve blocks were applied bilaterally using 2% lidocaine before rhinoscopy in eight dogs (EM group). Six dogs were premedicated with hydromorphone (0.05 mg/kg) as a substitute for local nerve block (H group). During rhinoscopy, the heart rate, arterial blood pressure and end-tidal isoflurane concentration were recorded. The vaporizer setting was adjusted to increase the end-tidal isoflurane concentration when reflex movement was caused by nasal stimulation.

RESULTS

The H group, compared to the EM group, had an increase in HR that was 18 beats/minute (95% CI: 11 to 26) higher, an increase in SAP that was 22 mmHg (12 to 31) higher, an increase in MAP that was 15 mmHg (7 to 23) higher, an increase in DAP that was 12 mmHg (5 to 19) higher, and an increase in end-tidal isoflurane concentration that was 0.4% (0.3 to 0.5) higher. Head movement due to endoscope insertion was observed in 5/6 dogs (83.3%) in the H group and 1/8 dogs (12.5%) in the EM group (odds ratio, 0.029; ra95% CI, 0.001-0.574).

CLINICAL SIGNIFICANCE

Compared with administration of 0.05 mg/kg hydromorphone, concurrent block of the ethmoidal and maxillary nerves can reduce the cardiovascular response, reflex movement and anaesthetic requirement during rhinoscopy in dogs.

A propensity score-adjusted analysis of efficacy of high-flow nasal oxygen during awake tracheal intubation

Oxygen supplementation is crucial for awake tracheal intubation (ATI) using a flexible bronchoscope in patients with an anticipated difficult airway. However, the modality of optimal oxygen delivery remains unclear. This retrospective study compared high-flow nasal oxygen (HFNO) and conventional low-flow oxygen supply during ATI. We applied inverse probability of treatment weighting (IPTW) to account for biases due to clinical characteristic differences between the groups. The primary endpoint was the lowest oxygen saturation during ATI. The secondary endpoints were incidence of desaturation, multiple attempts, failure rate, and procedural duration. After IPTW adjustment, the lowest oxygen saturation in the HFNO group during ATI was significantly higher than that in the conventional oxygenation group (99.3 ± 0.2 vs. 97.5 ± 0.5, P < 0.001). Moreover, the HFNO group had fewer cases with multiple attempts than the conventional oxygenation group (3% vs. 16%, P = 0.007). There were no significant differences between the two groups in the incidence of desaturation, failure and procedural duration. Our findings suggest that HFNO was associated with improved lowest oxygen saturation and a lower rate of multiple attempts during ATI. Therefore, we recommend using HFNO for safer oxygen delivery and improved quality of procedure during ATI.

AB0922 Psoriatic Arthritis Disease Activity Differs by Race/Ethnicity

Background

Psoriatic arthritis (PsA) affects up to 30% of individuals with psoriasis. Studies have demonstrated that the presenting disease severity and quality of life impact of psoriasis differs by race/ethnicity in patients with and without PsA, but little is known about disease activity among different racial/ethnic groups [1-3].

Objectives

The objective of our study was to evaluate disease activity by race/ethnicity among patients with PsA.

Methods

We performed a cross-sectional study of adult (≥18 years old) patients with PsA who had at least one outpatient visit within the University of Pennsylvania health system between 2010 and 2019. Patients with PsA were identified by the presence of at least two International Classification of Diseases (ICD)-9 or ICD-10 codes for PsA associated with two different healthcare encounters. The primary outcome was disease activity as measured by the Routine Assessment of Patient Index Data 3 (RAPID3) assessment. The RAPID3 score is a validated patient-reported measure of physical function, pain, and global status [4]. RAPID3 scores range from 0 to 30, with higher scores indicating greater disease activity. Patients were included if they had at least one documented RAPID3 score. For patients with multiple RAPID3 scores, the median value was used. The primary independent variable was race/ethnicity categorized as White (reference), Black, Asian, Hispanic, or other race. Multivariable linear regression was used to assess the relationship between race/ethnicity and RAPID 3 score.

Results

The study population included 742 patients. Mean (standard deviation [SD]) age was 47.2 (13.3) years and 57.4% were female. The racial/ethnic distribution was 79.4% White, 7.0% Black, 5.0% Asian, 3.1% Hispanic, 2.6% other race, and 3.0% missing race/ethnicity. The means of the median Rapid3 scores were statistically significantly different across racial/ethnic groups (p<.001): White mean (SD) 9.79 (6.02), Black mean (SD) 14.86 (14.86), Asian mean (SD) 9.79 (5.44), Hispanic mean (SD) 15.09 (7.11), other race mean (SD) 10.57 (6.91). In an adjusted multivariable model controlling for other sociodemographic factors, body mass index, treatment history, and medical comorbidity, Hispanic patients had higher RAPID3 scores compared to White patients, indicating greater disease activity (β 3.36; 95% confidence interval [CI] 1.04 – 5.67, p <.005). In exploratory stratified analyses to evaluate effect modification by sex, among males, Black (β 3.43; 95% CI 0.23 – 6.63, p=.04) and Hispanic (β 5.94; 95% CI 2.18 – 9.70, p <.005) patients had higher RAPID3 scores than White patients. Among females, no significant racial/ethnic differences in RAPID3 scores were identified.

Conclusion

Black and Hispanic patients report greater disease activity as indicated by higher RAPID3 scores compared to White patients. Larger studies are necessary to confirm our findings and understand the causes of racial/ethnic differences in disease activity among patients with PsA.

References

[1]Abrouk M, Lee K, Brodsky M, Nakamura M, Singh R, Zhu TH, et al. Ethnicity affects the presenting severity of psoriasis. J Am Acad Dermatol. 2017;77(1):180-2.

[2]Shah SK, Arthur A, Yang YC, Stevens S, Alexis AF. A retrospective study to investigate racial and ethnic variations in the treatment of psoriasis with etanercept. J Drugs Dermatol. 2011;10(8):866-72.

[3]Takeshita J, Augustin M, de Jong E, Lafferty K, Langholff W, Langley R, Leonardi C, Menter A, Alexis A. Psoriasis-Related Quality-of-Life Differs by Race/Ethnicity. J Invest Dermatol. 2019; 139(5S, Supplement 1):S148.

[4]Coates LC, Tillett W, Shaddick G, Pincus T, Kavanaugh A, Helliwell PS. Value of the Routine Assessment of Patient Index Data 3 in Patients With Psoriatic Arthritis: Results From a Tight-Control Clinical Trial and an Observational Cohort. Arthritis Care Res (Hoboken). 2018;70(8):1198-1205.

Disclosure of Interests

Fahad Ahmed: None declared, Alexis Ogdie Consultant of: A. Ogdie has received consulting fees from Amgen, AbbVie, Bristol Myers Squibb, Celgene, CorEvitas (formerly Corrona), Gilead, Janssen, Lilly, Novartis, Pfizer, and UCB., Grant/research support from: A. Ogdie has received grant support from the National Institutes of Health/National Institute of Arthritis and Musculoskeletal and Skin Diseases, Rheumatology Research Foundation, National Psoriasis Foundation, Abbvie (University of Pennsylvania), Pfizer (University of Pennsylvania), Amgen (FORWARD), and Novartis (FORWARD)., Robert Fitzsimmons: None declared, Daniel Shin: None declared, Junko Takeshita Consultant of: JT has served as a consultant for Pfizer Inc. and Janssen Biotech receiving honoraria., Grant/research support from: JT has received a research grant (to the Trustees of the University of Pennsylvania) from Pfizer Inc.

POS1049 ASSESSING TREATMENT PATTERNS WITH DISEASE-MODIFYING ANTIRHEUMATIC DRUGS AND PREDNISONE FOR PSORIATIC ARTHRITIS BY RACE/ETHNICITY

Background

Psoriatic arthritis (PsA) is a comorbidity commonly associated with psoriasis. Studies have demonstrated delays in the diagnosis and treatment of PsA[1] that may disproportionately affect racial/ethnic minority patients as indicated by one study that found Black Medicaid patients with PsA to be less likely to receive disease-modifying antirheumatic drugs [DMARDs] than White Medicaid patients with PsA [2]. Yet much remains unknown about potential racial/ethnic disparities in PsA management.

Objectives

The objective of our study was to evaluate treatment patterns for PsA by race/ethnicity.

Methods

We performed a cross-sectional study of adult (≥18 years old) patients with PsA who had at least one outpatient visit within the University of Pennsylvania health system between 2010 and 2019. Patients with PsA were identified by the presence of at least two International Classification of Diseases (ICD)-9 or ICD-10 codes for PsA associated with two different healthcare encounters. The primary outcomes were receipt of a prescription for: (i) an oral DMARD, (ii) a biologic DMARD, and (iii) prednisone. Oral DMARDs included apremilast, methotrexate, sulfasalazine, leflunomide, azathioprine, cyclosporine, tofacitinib, hydroxychloroquine, and upadacitnib. Biologic DMARDs included abatacept, adalimumab, brodalumab, certolizumab, etanercept, golimumab, guselkumab, infliximab, ixekixumab, secukinumab, ustekinumab, and risankizumab. The primary independent variable was race/ethnicity categorized as White (reference), Black, Asian, Hispanic, or other race. Multivariable logistic regression was used to assess the relationship between race/ethnicity and each treatment outcome.

Results

The study population included 1781 patients with PsA who were a mean age of 50.7 (SD 14.3), 54.6% female, and 72.5% commercially insured. The racial/ethnic distribution was 81.9% White, 5.6% Black, 4.0% Asian, 3.0% Hispanic, 2.5% other race, and 3.1% missing race/ethnicity. Of these patients, 64.3% were prescribed an oral DMARD, 55.6% were prescribed a biologic, and 44.1% were prescribed prednisone. There were no statistically significant differences across race/ethnicity for prescription of either oral or biologic DMARDs. However, prescription of prednisone did differ by race/ethnicity (p<.005) with Black (54.6%) and Hispanic (56.6%) patients being more likely to receive prednisone prescriptions and Asian (32.4%) patients being less likely to receive prednisone prescriptions than White (44.2%) patients. In adjusted logistic regression models controlling for sociodemographic and other factors, Hispanic patients were more likely to receive a prednisone prescription (OR 1.79, 95% CI 1.01 – 3.20, p=0.05) while Asian (OR 0.58, 95% CI 0.34 – 0.97, p=0.04) patients were less likely to receive a prednisone prescription compared to White patients.

Conclusion

We found Hispanic patients with PsA to be more likely to receive prednisone prescriptions than White patients with PsA but did not identify any racial/ethnic differences in prescription patterns for oral or biologic DMARDs for PsA. Greater use of prednisone among Hispanic patients may reflect different diseases trajectories (e.g., more disease flares or greater disease severity) or other factors that affect prescription patterns that require further study.

References

[1]Favier G, Gladman DD, Merola JF, Armstrong AW, Boehncke WH, Helliwell PS. Benchmarking Care in Psoriatic Arthritis - The QUANTUM Report: A Report from the GRAPPA 2016 Annual Meeting. J Rheumatol. 2017;44(5):674-678.

[2]Ogdie A, Matthias W, Thielen RJ, Chin D, Saffore CD. Racial Differences in Prevalence and Treatment for Psoriatic Arthritis and Ankylosing Spondylitis by Insurance Coverage in the USA. Rheumatol Ther. 2021;8(4):1725-1739.

Disclosure of Interests

Fahad Ahmed: None declared, Alexis Ogdie Consultant of: A. Ogdie has received consulting fees from Amgen, AbbVie, Bristol Myers Squibb, Celgene, CorEvitas (formerly Corrona), Gilead, Janssen, Lilly, Novartis, Pfizer, and UCB., Grant/research support from: A. Ogdie has received grant support from the National Institutes of Health/National Institute of Arthritis and Musculoskeletal and Skin Diseases, Rheumatology Research Foundation, National Psoriasis Foundation, Abbvie (University of Pennsylvania), Pfizer (University of Pennsylvania), Amgen (FORWARD), and Novartis (FORWARD)., Robert Fitzsimmons: None declared, Daniel Shin: None declared, Junko Takeshita Consultant of: JT has served as a consultant for Pfizer Inc. and Janssen Biotech receiving honoraria., Grant/research support from: JT has received a research grant (to the Trustees of the University of Pennsylvania) from Pfizer Inc.

Pre-ablation interatrial conduction delay or block predicts atrial fibrillation recurrence after ablation among obese patients

Funding Acknowledgements

Type of funding sources: None.

Background

Obesity is associated with greater risk of atrial fibrillation (AF) recurrence post-ablation and higher incidence of conduction delay compared to non-obese patients. Pre-ablation P-wave duration (PWD) and morphology (PWM) indicating interatrial delay are easily assessed in the clinic and may predict AF recurrence post-ablation in these patients.

Purpose

Evaluate the predictive value of PWD and PWM on AF recurrence post-ablation in obese patients.

Methods

Pre-ablation PWD and PWM (negative P-wave in lead II or III) were analyzed on consecutive patients with BMI ≥30 kg/m2 who underwent initial AF ablation from 2012–19. The primary outcome was recurrent AF after a 3-month post-ablation blanking period. Multivariate analysis adjusted for baseline characteristics was performed.

Results

For 205 patients (61.0±9.5 years old, 39.0% female), mean BMI was 36.9±5.7 kg/m2 and 71.7% had persistent AF pre-ablation. Recurrent AF post-ablation occurred in 115 (56.1%) during a median follow up of 491 (270, 1001) days. PWD &gt;130 ms was significantly associated with higher AF recurrence (AHR of 1.62, 95%CI 1.04-2.57, p=0.03) after adjusting for age, persistent AF and left atrial volume index (LAVI). In a subgroup with LAVI &lt;42 mL/m2 (n=112), PWD &gt;130 ms and negative P-waves in lead II or III were independently associated with increased risk of recurrent AF (AHR 2.06, 95%CI 1.12-3.91; p=0.019 and AHR 1.94, 95% CI 1.00-3.56; p=0.05, respectively) (Figure 1).

Conclusion

AF recurred in &gt;50% of obese patients within 1.5 years of ablation. Pre-ablation PWD &gt;130 ms and negative P-waves in lead II or III independently predicted recurrent AF post-ablation in this cohort of obese patients. These easily assessed findings add predictive value to other risk factors.

Effects of intraoperative dexmedetomidine infusion on renal function in elective living donor kidney transplantation: a randomized controlled trial

PURPOSE

Ischemia-reperfusion injury is inevitable during donor organ harvest and recipient allograft reperfusion in kidney transplantation, and affects graft outcomes. Dexmedetomidine, an α2-adrenoreceptor agonist, has renoprotective effects against ischemia-reperfusion injury. We investigated the effects of intraoperative dexmedetomidine infusion on renal function and the development of delayed graft function after elective living donor kidney transplantation in a randomized controlled trial.

METHODS

A total of 104 patients were randomly assigned to receive either an intraoperative infusion of dexmedetomidine 0.4 μg·kg^-1·hr^-1 or 0.9% saline. The primary outcome was the serum creatinine level on postoperative day (POD) 7. Secondary outcomes were renal function and the degree of inflammation and included the following variables: serum creatinine level and estimated glomerular filtration rate up to six months; incidence of delayed graft function; and levels of serum cystatin C, plasma interleukin (IL)-1β, and IL-18 during the perioperative period.

RESULTS

The mean (standard deviation) serum creatinine level on POD 7 was comparable between the groups (dexmedetomidine vs control: 1.11 [0.87] mg·dL^-1 vs 1.06 [0.73] mg·dL^-1; mean difference, 0.05; 95% confidence interval, -0.27 to 0.36; P = 0.77). Delayed graft function occurred in one patient in each group (odds ratio, 1.020; P > 0.99). There were no significant differences in the secondary outcomes between the groups (all P > 0.05).

CONCLUSIONS

Intraoperative dexmedetomidine infusion did not produce any beneficial effects on renal function or delayed graft function in patients undergoing elective living donor kidney transplantation.

STUDY REGISTRATION

www.ClinicalTrials.gov (NCT03327389); registered 31 October 2017.

Normative Data of Ocular Biometry, Optical Coherence Tomography, and Electrophysiology Conducted for Cynomolgus Macaque Monkeys

Purpose

To present normative data of optical coherence tomography (OCT) parameters, electrophysiological tests, and optical biometry conducted for cynomolgus monkeys.

Methods

Multimodal examinations were performed for 11 adult cynomolgus monkeys (Macaca fascicularis, weighing 2.6–7.5 kg, aged 45–99 months). A-scan biometry was performed to measure ocular biometry. OCT images were obtained at 30° and 55°. After the pupils were fully dilated, electroretinogram (ERG) and visual evoked potentials (VEP) were recorded with a commercial system using a contact lens electrode.

Results

All cynomolgus monkeys were males. The mean axial length was 17.92 ± 0.34 mm. The central total retinal layer (TRL) and subfoveal choroidal thicknesses were 286.27 ± 18.43 and 234.73 ± 53.93 µm, respectively. The TRL and nerve fiber layer thickness was greater in the nasal than in other quadrants in the Early Treatment Diabetic Retinopathy Study circle in the macula. Peripheral TRL and ganglion cell complex thickness on the temporal outside the vascular arcades were lower than on the other sides. The peak latency of a-wave and b-wave in scotopic and photopic 3.0 ERG was 14.78 ± 1.00 and 32.89 ± 1.81 ms, and 12.91 ± 1.03 and 31.79 ± 2.16 ms, respectively. The n2 wave peak latency of VEP was 15.21 ± 8.07 ms. The a-wave peak latency of ERG and the n2 wave peak latency of VEP negatively correlated with age.

Conclusions

The normative ocular biometric, electrophysiological test, and OCT parametric data of cynomolgus monkeys could serve as reference values for further preclinical studies.

Translational Relevance

We present normative data of cynomolgus monkeys’ eyes, an adequate animal model for preclinical studies.

Changing demographics, temporal trend in waitlist and post-transplant outcomes after heart transplantation in the United States: analysis of unos database 1991–2019

Background

The landscape of heart transplantation (HT) has changed significantly with respect to patient selection, surgical techniques, and patient outcomes. We sought to investigate temporal trends in patient characteristics, waitlist and post-transplant outcomes after HT in the U.S.

Methods

We queried the national database of the United Network of Organ Sharing (UNOS) to identify adults listed for HT in the U.S. between 1991 and 2019. Patients were divided into four eras based on the three time points in which changes were made to the patient selection/allocation policy (1999, 2006, and 2018), and patient characteristics as well as waitlist and post-transplant outcomes were evaluated for each era.

Results

Between 1991 and 2019, a total of 95,179 patients were added to the waitlist for HT in the U.S. Compared to era 1, patients listed in era 4 were older (mean age: 52.4 years), more female (27.6%) and ethnic minorities (40%), and with higher-risk comorbidities (28.8% diabetes, 35.6% obese). Over the study period, there were 22,070 waitlist deaths and 61,687 transplants.

Compared to the preceding era, there was significant decrease in waitlist mortality in the last 2 eras (e.g., sub-hazard ratio for era 4 vs era 3 =0.37, 95% CI=0.32–0.44). For each year, only 27.1% to 40.5% of those on the waitlist were transplanted. Among those who were transplanted, there was increase in the rates of in-hospital stroke (2.8% in era 1 to 3.7% in era 4), renal failure requiring dialysis (7.2% to 17.1%), and hospital length of stay (14 to 17 days), p-values&lt;0.001 for all. However, this has not negatively impacted short-term survival when compared to the preceding era (1-year graft survival = 89.7% in era 4). Based on a projection model, we predict a 47% increase in living adult heart transplant recipients to to 44,366 in 2040.

Conclusion

There have been significant changes in the characteristics of patients listed for HT in the U.S., including an increasing proportion of high-risk co-morbidities. Although the transplant volume has increased, the wide supply-demand gap persisted. The last 2 changes in the allocation policy in 2006 and 2018 achieved their primary objective of reducing waitlist mortality.

Funding Acknowledgement

Type of funding sources: None.

Molecular Dynamics Simulation to Uncover the Mechanisms of Protein Instability During Freezing

Freezing is a common process applied in the pharmaceutical industry to store and transport biotherapeutics. Herewith, multi-scale molecular dynamics simulations of Lactate dehydrogenase (LDH) protein in phosphate buffer with/without ice formation performed to uncover the still poorly understood mechanisms and molecular details of protein destabilization upon freezing. Both fast and slow ice growing conditions were simulated at 243 K from one or two-side of the simulation box, respectively. The rate of ice formation at all-atom simulations was crucial to LDH stability, as faster freezing rates resulted in enhanced structural stability maintained by a higher number of intramolecular hydrogen bonds, less flexible protein's residues, lower solvent accessibility and greater structural compactness. Further, protein aggregation investigated by coarse-grained simulations was verified to be initiated by extended protein structures and retained by electrostatic interactions of the salt bridges between charged residues and hydrogen bonds between polar residues of the protein. Lastly, the study of free energy of dissociation through steered molecular dynamics simulation revealed LDH was destabilized by the solvation of the hydrophobic core and the loss of hydrophobic interactions. For the first time, experimentally validated molecular simulations revealed the detailed mechanisms of LDH destabilization upon ice formation and cryoconcentration of solutes.

Residual functional SYNTAX score by quantitative flow ratio and improvement of exercise capacity after revascularization in patients with stable ischemic heart disease

Background

In patients with stable ischemic heart disease (SIHD), the efficacy of percutaneous coronary intervention (PCI) in improving exercise capacity has been under debate and the differential effect of PCI for exercise capacity, according to functional completeness of revascularization, has not been evaluated.

Purpose

This study aimed to evaluate the association between improvement in exercise capacity and functional completeness of revascularization, determined by residual functional SYNTAX score (rFSS), which is the sum of residual SYNTAX score of the vessels with post-PCI quantitative flow ratio (QFR)≤0.80.

Methods

Among patients enrolled in the QFR multicenter registry, 110 patients who underwent prespecified routine exercise treadmill tests before and after PCI were analyzed. Patients were classified into functional complete revascularization (CR) group (rFSS=0) and functional incomplete revascularization (IR) group (rFSS≥1). Increase of exercise time after PCI was compared between the 2 groups. Improvement of exercise capacity was defined as ≥10% increase of exercise time after PCI.

Results

Functional CR was achieved in 79 patients (71.8%), otherwise classified as functional IR in 31 patients (18.2%). There were no significant differences in baseline characteristics including medication profiles. Increase of exercise time was significantly associated with increase of 3-vessel QFR (r=0.198, P=0.038) and rFSS (r=−0.312, P&lt;0.001), but not with decrease of SYNTAX score (r=0.097, P=0.313). The rFSS showed significantly higher c-index to predict the improvement of exercise capacity after PCI than increase of 3-vessel QFR or decrease of SYNTAX score (0.722 vs. 0.627 vs. 0.492, respectively, P&lt;0.001). Patients with functional CR, defined by rFSS, showed significantly higher increase of exercise time than those with functional IR (97.7 sec vs. 12.5 sec, P&lt;0.001). Functional CR was an independent predictor of the improvement of exercise capacity after PCI (adjusted odds ratio 4.656, 95% CI 1.678–12.920, P=0.002).

Conclusions

Integrated anatomic and functional scoring system (rFSS) was significantly associated with improvement of exercise capacity after PCI. SIHD patients with functional CR, defined by rFSS, showed significantly higher exercise capacity after PCI than those with functional IR.

Summarizing Figure

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): SaeHan NK & D and Medis Corporation

Realizing Cancer Precision Medicine by Integrating Systems Biology and Nanomaterial Engineering

Many clinical trials for cancer precision medicine have yielded unsatisfactory results due to challenges such as drug resistance and low efficacy. Drug resistance is often caused by the complex compensatory regulation within the biomolecular network in a cancer cell. Recently, systems biological studies have modeled and simulated such complex networks to unravel the hidden mechanisms of drug resistance and identify promising new drug targets or combinatorial or sequential treatments for overcoming resistance to anticancer drugs. However, many of the identified targets or treatments present major difficulties for drug development and clinical application. Nanocarriers represent a path forward for developing therapies with these "undruggable" targets or those that require precise combinatorial or sequential application, for which conventional drug delivery mechanisms are unsuitable. Conversely, a challenge in nanomedicine has been low efficacy due to heterogeneity of cancers in patients. This problem can also be resolved through systems biological approaches by identifying personalized targets for individual patients or promoting the drug responses. Therefore, integration of systems biology and nanomaterial engineering will enable the clinical application of cancer precision medicine to overcome both drug resistance of conventional treatments and low efficacy of nanomedicine due to patient heterogeneity.

Combined Positive and Negative Feedback Allows Modulation of Neuronal Oscillation Frequency during Sensory Processing

A key step in sensory information processing involves modulation and integration of neuronal oscillations in disparate frequency bands, a poorly understood process. Here, we investigate how top-down input causes frequency changes in slow oscillations during sensory processing and, in turn, how the slow oscillations are combined with fast oscillations (which encode sensory input). Using experimental connectivity patterns and strengths of interneurons, we develop a system-level model of a neuronal circuit controlling these oscillatory behaviors, allowing us to understand the mechanisms responsible for the observed oscillatory behaviors. Our analysis discovers a circuit capable of producing the observed oscillatory behaviors and finds that a detailed balance in the strength of synaptic connections is the critical determinant to produce such oscillatory behaviors. We not only uncover how disparate frequency bands are modulated and combined but also give insights into the causes of abnormal neuronal activities present in brain disorders.

Massive clonal expansion of medulloblastoma-specific T cells during adoptive cellular therapy

In both human and murine systems, we have developed an adoptive cellular therapy platform against medulloblastoma and glioblastoma that uses dendritic cells pulsed with a tumor RNA transcriptome to expand polyclonal tumor-reactive T cells against a plurality of antigens within heterogeneous brain tumors. We demonstrate that peripheral TCR Vβ repertoire analysis after adoptive cellular therapy reveals that effective response to adoptive cellular therapy is concordant with massive in vivo expansion and persistence of tumor-specific T cell clones within the peripheral blood. In preclinical models of medulloblastoma and glioblastoma, and in a patient with relapsed medulloblastoma receiving adoptive cellular therapy, an early and massive expansion of tumor-reactive lymphocytes, coupled with prolonged persistence in the peripheral blood, is observed during effective therapeutic response to immunotherapy treatment.

Adrenal insufficiency in systematic lupus erythematosus (SLE) and antiphospholipid syndrome (APS): A systematic review

BACKGROUND

Adrenal insufficiency (AI) is associated with high morbidity and mortality. The aim of this systematic review was to enhance diagnostic approaches and summarize therapeutic strategies in the management of AI in patients with systematic lupus erythematosus (SLE) or antiphospholipid syndrome (APS).

METHODS

A literature search of PubMed and Medline databases was performed and 91 publications containing 105 cases were included for the final analysis.

RESULTS

The following frequency of clinical signs and symptoms was noted: abdominal pain (39.04%) was the leading symptom, followed by fever (33.33%), vomiting (23.81%), and nausea (19.05%). APS was present in 73%, SLE in 17% of the patients, while 2% had a diagnosis of both, SLE and APS. ACTH stimulation test (ACTHst) was performed in 18% of cases and 76.6% of them were unresponsive towards stimulation. Variable treatment approaches were used: hydrocortisone was most commonly used (38.09%), followed by fludrocortisone (26.67%), prednisolone (20.00%) and volume replacement treatment (11.43%), respectively.

CONCLUSIONS

This analysis highlights the importance of an early diagnosis and initiation of therapeutic management when AI is suspected. In line, signs and symptoms related to autoimmune diseases in patients with AI should be reviewed crtitically.