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Ryu, Alexander J.

https://orcid.org/0000-0002-0138-5112

Mayo Clinic

WinnMed

Citations 29

Effect of Hydrogen Sulfide on [Ca2+]i Regulation in Airway Smooth Muscle
Ryu, Alexander J. , Ryu, Alexander J. , Thompson, Michael James , Sathish, Venkatachalem , Pabelick, Christina M. , Prakash, Y. S.

The FASEB Journal | June 21, 2021 | Volume: 23 | Issue: S1 | Pages: No page available

10.1096/fasebj.23.1_supplement.622.5 Get It

There is increasing interest in the role of hydrogen sulfide (H 2 S) as a gasotransmitter similar to nitric oxide and carbon monoxide. In this study, we examined the role of H 2 S in airway smooth muscle (ASM) inflammation. H 2 S is produced by the enzymes cystathionine beta‐synthase (CBS) and cystathionine gamma‐lysase (CTH). Both of these enzymes were detected in human ASM by Western blot analysis. In tissues exposed to the pro‐inflammatory cytokine tumor necrosis factor‐a (TNFα) both CTH and CBS expression were upregulated. In ASM strips contracted with 10 µM ACh, only exposure to 1 mM of the H 2 S donor NaHS induced relaxation. Human ASM cells loaded with fura‐2 demonstrated a dose‐dependent decrease in intracellular calcium concentration ([Ca 2+ ] i ) to NaHS (50‐250 μM), in the presence of either 1 μM ACh or 10 μM histamine. However, sodium sulfide (Na 2 S, 100 µM up to 1 mM) showed no effect on [Ca 2+ ] i . Exposure to 60 mM KCl in the presence of either NaHS or Na 2 S (50 μM‐3 mM) did not affect [Ca 2+ ] i . Relaxant effects of NaHS or Na 2 S on ACh‐induced [Ca 2+ ] i elevation were absent when experiments were conducted in zero extracellular Ca 2+ . These results suggest that H 2 S relaxes ASM and reduces [Ca 2+ ] i by affecting Ca 2+ influx, potentially via voltage‐gated channels, but does not affect sarcoplasmic reticulum Ca 2+ release. The relevance of endogenous H 2 S generation in ASM, and its role in infalmmation needs to be explored further. Supported by the Flight Attendants Medical Research Institute (FAMRI), NIH grant HL74309, and the Department of Anesthesiology, Mayo Clinic.
An under‐recognized phenomenon: Myocardial volume change during the cardiac cycle
Kumar, Vinayak , Rao, Chaitanya, Ryu, Alexander J. , Gibbons, Raymond J. , Chandrasekaran, Krishnaswamy , Asirvatham, Samuel J. , Araoz, Philip A. , Oh, Jae K. , Egbe, Alexander C. , Behfar, Atta , Anavekar, Nandan S., Behfar, Atta , Asirvatham, Samuel J , Kumar, Vinayak , Manduca, Armando , Ryu, Alexander J. , Gersh, Bernard J. , Borlaug, Barry A.

Echocardiography | June 4, 2021 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1111/echo.15093 Get It

Abstract 15635: Myocardial Function Index Predicts Mortality in Amyloid Light Chain Cardiomyopathy
Anand, Vidhu , Ryu, Alexander J. , Anavekar, Nandan S., Chandrasekaran, Krishnaswamy , Akhiyat, Nadia , Ryu, Alexander J. , Kumar, Vinayak , Borlaug, Barry A. , AbouEzzeddine, Omar F. , Gibbons, Raymond J. , Gersh, Bernard J.

Circulation | May 10, 2021 | Volume: 142 | Issue: Suppl_3 | Pages: No page available

10.1161/circ.142.suppl_3.15635 Get It

Introduction: Cardiovascular disease remains the leading cause of morbidity and mortality in patients with amyloid light chain (AL) amyloidosis. Current prognostic evaluation in AL cardiomyopathy (AL-CM) largely relies upon disparate proxy measurements to assess mortality. With respect to observed myocardial volume changes between systole and diastole, we describe a single measurement derived from cardiac MRI (CMR) to assess mortality of AL-CM. Methods: A cohort of 129 consecutive patients with AL-CM undergoing CMR with amyloid protocol from the years 2001 - 1997 was reviewed. Myocardial volume change at end systole and end diastole was assessed by disc summation with CMR. The myocardial function index (MFI) was calculated by consolidating blood pool and myocardial volume measures as confluent components of myocardial function utilizing operator tracings. The association of MFI and death was assessed with adjusted hazard ratios (HR) derived by a Cox model. Results: Data at time of CMR was reviewed. The mean age was 60 ±10; 68% subjects were female. Median survival from CMR was 47 months. Mean LVEF was assessed by echocardiography to be 55% ± 12. Mean calculated MFI was 19.8% ±7. Univariate analysis suggested MFI is strongly associated with death (HR 0.004; 95%CI 0.00002-0.0838; p = 0.0003). A multivariate analysis re-demonstrated the strong predictive value of MFI when controlled for age (HR 0.006; 95%CI 0.00003 - 0.1156; p = 0.0006). Conclusion: MFI strongly correlates with mortality in AL-CM. In contrast to previously described assessments of ventricular function (extracellular volume imaging, myocardial perfusion imaging, and myocardial contraction fraction), MFI is easily derived from CMR and considers blood pool and myocardial volumes as confluent components of myocardial function. Further studies are needed to assess MFI amongst patients with varying etiologies of heart failure.
Practical development and operationalization of a 12-hour hospital census prediction algorithm
Ryu, Alexander J. , Romero‐Brufau, Santiago , Shahraki, Narges, Zhang, Jiawei , Qian, Ray , Kingsley, Thomas C. , Romero-Brufau, Santiago , Ryu, Alexander J.

Journal of the American Medical Informatics Association | April 30, 2021 | Volume: 28 | Issue: 9 | Pages: 1977-1981

10.1093/jamia/ocab089 Get It

Abstract Hospital census prediction has well-described implications for efficient hospital resource utilization, and recent issues with hospital crowding due to CoVID-19 have emphasized the importance of this task. Our team has been leading an institutional effort to develop machine-learning models that can predict hospital census 12 hours into the future. We describe our efforts at developing accurate empirical models for this task. Ultimately, with limited resources and time, we were able to develop simple yet useful models for 12-hour census prediction and design a dashboard application to display this output to our hospital’s decision-makers. Specifically, we found that linear models with ElasticNet regularization performed well for this task with relative 95% error of +/− 3.4% and that this work could be completed in approximately 7 months.
A framework for living evidence synthesis in cancer: Living, interactive network meta-analysis for first-line treatment of metastatic renal cell carcinoma (mRCC).
Ryu, Alexander J. , Naqvi, Syed Arsalan Ahmed , Maheswari, Deepa, Sipra, Qurat Ul Ain Riaz , Pagliaro, Lance C. , Costello, Brian A. , Riaz, Irbaz Bin , He, Huan , Ryu, Alexander J. , Siddiqi, Rabbia , Yao, Yuan , Husnain, Muhammad , Montori, Víctor M. , Joseph, Richard W. , Liu, Hongfang , Wang, Zhen , Herasevich, Vitaly , Singh, Parminder Pal , Ho, Thai H. , Bryce, Alan H. , Murad, M. Hassan

Journal of Clinical Oncology | March 2, 2021 | Volume: 39 | Issue: 6_suppl | Pages: 335-335

10.1200/jco.2021.39.6_suppl.335 Get It

335 Background: Systematic reviews are outdated quickly when the evidence is rapidly evolving as the process is laborious and there is little incentive for primary author team of an index SRMA to update the evidence. Consequently, there is an epidemic of redundant SRMAs performed by different teams—sometimes with conflicted results—for treatment of first line mRCC. Methods: We have created a living, interactive systematic review (LISR)and network meta-analysis(LINMA) for the treatment of first line mRCC using an Artificial intelligence (AI) assisted framework for evidence synthesis (Living, Interactive evidence synthesis framework) (LIvE) . The framework is implemented in five-layered architecture (application layer, shared module layer, core service layer, middleware layer, and storage layer) which work together to automate the identification of new studies and analysis and semi-automate the screening and data extraction. Dynamic features such as interactive tables, figures and evidence maps are enabled using Python and JavaScript programming languages. Results: We have maintained a living, interactive evidence profile for the first line treatment mRCC since September 2019 ( LIVING WEBSITE) . Living search strategy identifies new studies as they become available. As of October 13, 2020 LISR, includes data 14 clinical trials ( PRISMA ). Baseline characteristics are summarized in an interactive table ( TABLE) . Cabozantinib& Nivolumab (Cabo-Nivo) is the highest ranked drug for improving Overall Response (OR), Progression Free Survival (PFS) and Overall Survival (OS) whereas Ipilimumab in combination with Nivolumab (Ipi-Nivo) is highest ranked drug for achieving complete response (CR). Ipi-Nivo and Atezolizumab & Bevacizumab (Ate-Bev) ranked highest and Cabo-Nivo ranked lowest for treatment related Adverse events (TRAEs). Results of network meta-analysis are summarized as interactive tables and plots ( NMA ), summary of findings tables ( MULTIPLE COMAPRISONS ) and evidence maps ( MAP ). Conclusions: LISRs can potentially reduce redundancy, increase transparency, reproducibility, enable shared-decision making (at a guideline level, or in a patient-clinician dyad) and support living guidelines.
Cost-effectiveness of novel antiandrogens (AAs) for treatment of nonmetastatic castrate-resistant prostate cancer (nmCRPC).
Lang, Daenielle K., Asghar, Noureen, Riaz, Anum, Sipra, Qurat Ul Ain Riaz , Ryu, Alexander J. , Oh, Mok , Abraham, Ivo , Riaz, Irbaz Bin , Almutairi, Abdulaali R. , Yao, Yuan , Ryu, Alexander J. , Alkhatib, Nimer S. , Murad, M. Hassan , Kohli, Manish

Journal of Clinical Oncology | May 25, 2020 | Volume: 38 | Issue: 15_suppl | Pages: 5583-5583

10.1200/jco.2020.38.15_suppl.5583 Get It

5583 Background: FDA has approved three novel AAs [Apalutamide(A), Darolutamide(D) and Enzalutamide(E)] in combination with Androgen deprivation therapy ( ADT) for treatment of (nmCRPC) patients (pts). We report the cost-effectiveness of these drugs from the US perspective to help facilitate the choice of these agents for clinical practice. Methods: A life time Markov state-transition model was constructed with three health states (Metastasis-Free Survival[MFS], Metastatic disease, and Death) to compare cost-effectiveness of AA therapies for treatment of nmCRPC based on US healthcare payer perspective. A network meta-analysis of MFS and OS was conducted due to the lack of head to head trials. An approximation of the original individual-level patient time-to-event data were derived from digitized Kaplan-Meier curves for OS and MFS. Weibull distributions was selected as the best fitted model fitted and extrapolated as per the NICE decision support unit recommendations. Medication costs were based on wholesale acquisition cost. Adverse event (AE) grades 3/4 management costs were incorporated in the model. Discount rate of 3% per year was applied to costs and effects. Life years (LYs) and quality adjusted life years (QALYs) for each treatment as well as the incremental cost effectiveness (ICER) and cost utility (ICUR) ratios were estimated. Base case analyses (BCA) and probabilistic sensitivity analyses (PSA) were estimated. Results: The table summarizes the results form BCA analyses. A+ADT offers best gain in LYs (8.37yrs) and QALYs (5.30 yrs) but at higher cost. Conclusions: Apalutamide was associated with gains in LYs and QALYs traded off with higher lifetime cost relative to other AA alternatives. ADT was associated with lower gains in LYs and QALYs traded off with lower lifetime cost relative to other alternatives. Based on a $150,000/QALY threshold pay off, A+ADT is likely more cost effective compared to E+ADT or ADT alone; while E+ ADT may be more cost effective compared to D+ ADT. [Table: see text]
A systematic review and network meta-analysis of first-line treatment options in patients metastatic renal cell carcinoma.
Ryu, Alexander J. , Mathew, Jessey , Sipra, Qurat Ul Ain Riaz , Zahoor, Haris, Pagliaro, Lance C. , Costello, Brian A. , Riaz, Irbaz Bin , Ryu, Alexander J. , Yao, Yuan , Siddiqi, Rabbia , Wang, Zhen , Murad, M. Hassan

Journal of Clinical Oncology | February 19, 2020 | Volume: 38 | Issue: 6_suppl | Pages: 709-709

10.1200/jco.2020.38.6_suppl.709 Get It

709 Background: Several immunotherapy (IMT) combinations either as an IMT doublet or IMT in combination with TKIs are now available for first-line therapy of metastatic renal cell carcinoma (mRCC). In the absence of head-to-head clinical trials, we performed an indirect comparison of frontline treatment options to provide clinical guidance. Methods: Medline, Embase and Cochrane Library were searched to identify relevant trials. Hazard ratios (HR) and confidence interval (CI) for primary outcome of progression-free survival (PFS) and secondary outcome of overall survival (OS) were abstracted. Network meta-analysis was performed using a multivariate, consistency model, random-effects meta-regression. Data on Grade 3 or higher AEs was abstracted and meta-analyzed. Pre-specified subgroup analyses were performed based on risk categories (high risk vs low and intermediate vs), history of prior nephrectomy, PD-L1 positivity, age and sex. Risk for bias(RoB) was assessed using the Cochrane Collaboration’s tool. Results: Nine studies were included for PFS analysis, and 6 studies for OS analysis. Avelumab-axitinib (AA) (HR 0.69, 0.48-0.96), and Pembrolizumab-Axitinib (PA) (HR 0.89, 0.50-0.96) significantly improved PFS, while there was no significant PFS benefit with atezolizumab-bevacizumab (AB) (HR 0.83, 0.62-1.13) and nivolumab-ipilimumab (NI) (HR 0.85, 0.63-1.15) as compared to Sunitinib. PA (HR 0.53, 0.38-0.75) and NI (HR 0.63, 0.44-0.90) significantly improved OS, while AB (HR 0.93, 0.75-1.12) showed no significant OS benefit as compared to Sunitinib. NI and AB had significantly fewer grade ≥3 AE than sunitinib. No significant interaction was found by risk group, age, sex or prior nephrectomy. Significant interaction was found by PD-L1 expression(p<0.001), with significant PFS improvement in PD-L1 positive (HR 0.62, 0.53-0.73) but not in PD-L1 negative patients (HR 0.92, 0.81-1.05). Overall, RoB was low amongst included studies. Conclusions: AA improved PFS, NI improved OS, whereas PA improve both PFS and OS as compared to sunitinib monotherapy. However, no IMT combination was superior to other combinations. Cost effectiveness analysis will be reported separately.
Adjuvant therapy in high-risk renal cell cancer: A systematic review and cumulative meta-analysis.
Islam, Mahnoor, Sipra, Qurat Ul Ain Riaz , Ryu, Alexander J. , Raina, Ammad, Siddiqi, Rabbia , Riaz, Irbaz Bin , Ryu, Alexander J. , Murad, M. Hassan , Kohli, Manish

Journal of Clinical Oncology | February 19, 2020 | Volume: 38 | Issue: 6_suppl | Pages: 708-708

10.1200/jco.2020.38.6_suppl.708 Get It

708 Background: Patients with high risk non-metastatic renal cell cancer (RCC) are at significant risk of recurrence following nephrectomy. Previously, we reported no benefit of adjuvant tyrosine kinase inhibitor (TKI) treatment in high-risk patients. Since our most recent publication, efficacy results from the multicenter double-blind SORCE trial have become available. We updated our meta-analysis to include these additional data and performed a cumulative meta-analysis. Methods: PubMed, Embase, Web of Science, and Cochrane Central Register of Controlled Trials were searched to identify relevant RCTs. A generic variance-weighted random effects model was used to derive estimates for efficacy. Heterogeneity was assessed using the Cochran Q statistic and was quantified using the I2 test. The primary outcome was disease-free survival (DFS), defined as the interval between randomization and the first recurrence, the occurrence of metastasis or a secondary cancer, or death due to any cause. Statistical analysis was performed using Comprehensive Meta-Analysis version 3 (Biostat). Results: Five phase 3 trials were identified, enrolling 6531 patients. Two trials compared sunitinib with placebo (S-TRAC and ECOG-ACRIN), two compared sorafenib with placebo (ECOG-ACRIN and SORCE) and one trial each compared pazopanib (PROTECT) and axitinib (ATLAS) vs placebo. Cumulative evidence suggests that adjuvant therapy with TKIs showed no significant improvement in (DFS) hazard ratio [HR] of 0.93 (95% CI, 0.85-1.02), compared to placebo. There was no significant heterogeneity among included trials ( I2= 52%, P= .41). Overall, the trials were at low risk of bias. Conclusions: Adjuvant vascular endothelial growth factor tyrosine kinase inhibitors in high-risk renal cell carcinoma did not improve DFS as compared to placebo. Improved patient selection using better prognostic biomarkers or scoring systems may identify subsets of patients who can benefit from adjuvant treatments. Toxicity estimates will be updated as data from SORCE trial publication becomes available.
Caveolin-1 and force regulation in porcine airway smooth muscle
Sathish, Venkatachalem , Yang, Binxia , Meuchel, Lucas W., VanOosten, Sarah Kay, Ryu, Alexander J. , Prakash, Y. S. , Ryu, Alexander J. , Thompson, Michael A. , Pabelick, Christina M. , Prakash, Y S , Sathish, Venkatachalem

American Journal of Physiology-Lung Cellular and Molecular Physiology | March 19, 2011 | Volume: 300 | Issue: 6 | Pages: L920-L929

10.1152/ajplung.00322.2010 Get It

Caveolae are specialized membrane microdomains expressing the scaffolding protein caveolin-1. We recently demonstrated the presence of caveolae in human airway smooth muscle (ASM) and the contribution of caveolin-1 to intracellular calcium ([Ca2+]i) regulation. In the present study, we tested the hypothesis that caveolin-1 regulates ASM contractility. We examined the role of caveolins in force regulation of porcine ASM under control conditions as well as TNF-α-induced airway inflammation. In porcine ASM strips, exposure to 10 mM methyl-β-cyclodextrin (CD) or 5 μM of the caveolin-1 specific scaffolding domain inhibitor peptide (CSD) resulted in time-dependent decrease in force responses to 1 μM ACh. Overnight exposure to the cytokine TNF-α (50 ng/ml) accelerated and increased caveolin-1 expression and enhanced force responses to ACh. Suppression of caveolin-1 with small interfering RNA mimicked the effects of CD or CSD. Regarding mechanisms by which caveolae contribute to contractile changes, inhibition of MAP kinase with 10 μM PD98059 did not alter control or TNF-α-induced increases in force responses to ACh. However, inhibiting RhoA with 100 μM fasudil or 10 μM Y27632 resulted in significant decreases in force responses, with lesser effects in TNF-α exposed samples. Furthermore, Ca2+sensitivity for force generation was substantially reduced by fasudil or Y27632, an effect even more enhanced in the absence of caveolin-1 signaling. Overall, these results indicate that caveolin-1 is a critical player in enhanced ASM contractility with airway inflammation.