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394 citation(s) found for "Iyer, P G".

S356 Long-Term (> 5 Year) Outcomes of Endoscopic Resection for T1 Esophageal Adenocarcinoma: A Multicenter Cohort Study
Song, Kevin , Thanawala, Shivani U. , Facg, Ginsberg, Gregory G. , Wolfsen, Herbert, Ramirez, Francisco C. , Wang, Kenneth T. , Iyer, Prasad G. , Kahn, Allon , Agarwal, Siddharth, McDonald, Nicholas , Falk, Gary W.

American Journal of Gastroenterology | October 24, 2021 | Volume: 116 | Issue: 1 | Pages: S154-S154

10.14309/01.ajg.0000773896.61781.22 Get It

Predictors of Left Ventricular Outflow Tract Obstruction After Transcatheter Mitral Valve Replacement in Severe Mitral Annular Calcification: An Analysis of the Transcatheter Mitral Valve Replacement in Mitral Annular Calcification Global Registry
Sabbagh, Abdallah El , Al‐Hijji, Mohammed , Wang, Dee Dee , Eleid, Mackram F. , Ureña, Marina , Himbert, Dominique , Chakravarty, Tarun , Fang, Hao , Zahr, Firas , Dvir, Danny , Sardar, Muhammad , Cheema, Asim N. , Alnasser, Sami , Iyer, Vijay , Kaddissi, Georges, Webb, John G. , Makkar, Raj , Vahanian, Alec , Rihal, Charanjit S. , Eleid, Mackram F , Nejjari, Mohammed , Dvir, Danny , Rihal, Charanjit, Guerrero, Mayra E , Al-Hijji, Mohammed A , Wang, Dee Dee , Holzhey, David Michael , Pershad, Ashish , Nejjari, Mohammed , O’Neill, William W. , Rihal, Charanjit S. , Guerrero, Mayra

Circulation: Cardiovascular Interventions | October 19, 2021 | Volume: 14 | Issue: 10 | Pages: No page available

10.1161/circinterventions.121.010854 | PMID 34665654 Get It

Background: Several studies have evaluated preprocedural imaging predictors of left ventricular outflow tract obstruction (LVOTO) after transcatheter mitral valve replacement. The patient cohorts in these studies were heterogeneous and included patients with transcatheter mitral valve replacement in failed bioprostheses, annuloplasty rings, and severe mitral annular calcification (MAC). The goal of this study was to evaluate predictors of LVOTO specific to patients undergoing valve-in-MAC. Methods: This study included patients with severe MAC who underwent valve-in-MAC and had optimal quality preprocedural multidetector row computed tomography scans eligible for retrospective analysis. Baseline demographic, echocardiographic, and procedural data on these patients were collected. multidetector row computed tomography parameters were analyzed for association with LVOTO, defined as increase in mean LVOT gradient by ≥10 mm Hg with accompanying hemodynamic instability. Results: Seventy-one patients with optimal preprocedural computed tomography scans were included in this study (mean age, 72.5±13.5 years), 9 of which developed LVOTO (all female). Baseline mean LVOT area, neo-LVOT area (145.3 versus 270.9 mm 2 ; P =0.006), indexed neo-LVOT area (90.1 versus 157.4; P =0.05), and virtual transcatheter heart valve to septum distance (3.1 versus 6.9 mm; P =0.002) were lower in the LVOTO group. Expected % LVOT area reduction was higher in the latter group (58.3 versus 42.7%; P =0.008). In the univariable analysis, the baseline mean LVOT area, neo-LVOT area, indexed neo-LVOT area, and valve to septum distance were all significantly associated with LVOTO. Conclusions: The systolic mean LVOT area, neo-LVOT area, indexed neo-LVOT, expected percentage LVOT area reduction, and the valve to septum distance were associated with LVOTO after valve-in-MAC.
First-in-Human Study of MANP: A Novel ANP (Atrial Natriuretic Peptide) Analog in Human Hypertension
Chen, Horng H. , Wan, Siu‐Hin , Cannone, Valentina , Sangaralingham, S. Jeson , Nuetel, Joel, Burnett, John C. , Iyer, Seethalakshmi R., Sangaralingham, S. Jeson , Iyer, Seethalakshmi

Hypertension | October 18, 2021 | Volume: 78 | Issue: 6 | Pages: 1859-1867

10.1161/hypertensionaha.121.17159 | PMID 34657445 Get It

M-atrial natriuretic peptide (MANP) is a novel ANP (atrial natriuretic peptide) analog engineered to be an innovative particulate GC-A (guanylyl cyclase A) receptor activator. The rationale for its design was to develop a best-in-class GC-A activator with enhanced cGMP activating, natriuretic, aldosterone-suppressing, and blood pressure–lowering actions, compared with endogenous ANP, for the treatment of hypertension. Here, we report the first-in-human study on the safety, tolerability, neurohumoral, renal, and blood pressure–lowering properties of MANP in hypertension subjects. This was an open-label sequential single ascending dose design in which all subjects stopped all antihypertensive agents for 14 days before receiving a single subcutaneous injection of MANP. MANP was safe, well tolerated, activated cGMP, induced natriuresis, reduced aldosterone, and decreased blood pressure at or below the maximal tolerated dose. Thus, MANP has a favorable safety profile and produced expected pharmacological effects in human hypertension. Our results support further investigations of MANP as a potential future blood pressure–lowering, natriuretic and aldosterone-suppressing drug for hypertension especially resistant hypertension.
Leveraging electrophysiologic correlates of word encoding to map seizure onset zone in focal epilepsy: Task‐dependent changes in epileptiform activity, spectral features, and functional connectivity
Saboo, Krishnakant , Balzekas, Irena , Křemen, Václav , Varatharajah, Yogatheesan , Saboo, Krishnakant V , Kucewicz, Michal, Kremen, Vaclav , Kucewicz, Michał T. , Iyer, Ravishankar K. , Worrell, Gregory A.

Epilepsia | September 18, 2021 | Volume: 62 | Issue: 11 | Pages: 2627-2639

10.1111/epi.17067 | PMID 34536230 Get It

Abstract Objective Verbal memory dysfunction is common in focal, drug‐resistant epilepsy (DRE). Unfortunately, surgical removal of seizure‐generating brain tissue can be associated with further memory decline. Therefore, localization of both the circuits generating seizures and those underlying cognitive functions is critical in presurgical evaluations for patients who may be candidates for resective surgery. We used intracranial electroencephalographic (iEEG) recordings during a verbal memory task to investigate word encoding in focal epilepsy. We hypothesized that engagement in a memory task would exaggerate local iEEG feature differences between the seizure onset zone (SOZ) and neighboring tissue as compared to wakeful rest (“nontask”). Methods Ten participants undergoing presurgical iEEG evaluation for DRE performed a free recall verbal memory task. We evaluated three iEEG features in SOZ and non‐SOZ electrodes during successful word encoding and compared them with nontask recordings: interictal epileptiform spike (IES) rates, power in band (PIB), and relative entropy (REN; a functional connectivity measure). Results We found a complex pattern of PIB and REN changes in SOZ and non‐SOZ electrodes during successful word encoding compared to nontask. Successful word encoding was associated with a reduction in local electrographic functional connectivity (increased REN), which was most exaggerated in temporal lobe SOZ. The IES rates were reduced during task, but only in the non‐SOZ electrodes. Compared with nontask, REN features during task yielded marginal improvements in SOZ classification. Significance Previous studies have supported REN as a biomarker for epileptic brain. We show that REN differences between SOZ and non‐SOZ are enhanced during a verbal memory task. We also show that IESs are reduced during task in non‐SOZ, but not in SOZ. These findings support the hypothesis that SOZ and non‐SOZ respond differently to task and warrant further exploration into the use of cognitive tasks to identify functioning memory circuits and localize SOZ.
Changes in National Google Trends and Local Healthcare Utilization After High-Impact Gastroenterology Publications
Kamboj, Amrit K. , Chedid, Victor , Iyer, Prasad G. , Bailey, Kent R. , Harmsen, William S. , Katzka, David A. , Agarwal, Siddharth , Chedid, Victor G , Agarwal, Siddharth , Agarwal, Siddharth

American Journal of Gastroenterology | September 17, 2021 | Volume: 116 | Issue: 12 | Pages: 2465-2469

10.14309/ajg.0000000000001516 | PMID 34534126 Get It

INTRODUCTION: We examined national Google Trends and local healthcare utilization after 3 high-impact gastroenterology publications. METHODS: Changes in US Google Trends and Olmsted County health utilization were studied. RESULTS: Publication views within 30 days were 51,458 ( Imperiale ), 49,759 ( Pimentel ), and 18,750 ( Gomm ). Colonoscopy searches ( P = 0.04) and Cologuard tests performed ( P < 0.01) increased while colonoscopies decreased ( P < 0.01). Searches for rifaximin ( P = 0.05), irritable bowel syndrome ( P < 0.01), diarrhea ( P < 0.01), and rifaximin prescriptions ( P = 0.02) increased. Increase in hydrogen-2 blocker searches ( P = 0.02) and prescriptions ( P < 0.01) and gastroesophageal reflux disease ( P < 0.01) and dementia office visits ( P < 0.01) occurred. DISCUSSION: High-impact gastroenterology publications influence Google searches and local population-based healthcare utilization.
Abstract 10: MANP Activation of the Cyclic GMP/PDE2/CYP11B2 Pathway Inhibits Aldosterone In Vitro and In Vivo
Chen, Yang , Lee, Hon-chi, Burnett, John C. , Iyer, Seethalakshmi , Nikolaev, Viacheslav O. , Naro, Fabio , Pellegrini, Manuela

Hypertension | August 27, 2021 | Volume: 78 | Issue: Suppl_1 | Pages: No page available

10.1161/hyp.78.suppl_1.10 Get It

Aldosterone is a critical driver for cardiovascular disease (CVD). We recently discovered that MANP, a novel atrial natriuretic peptide (ANP) analog, possessed more potent aldosterone inhibitory action than ANP. MANP is currently entering clinical trials for hypertension and thus understanding its aldosterone suppressing mechanism is important. The mechanism of aldosterone inhibition by natriuretic peptides (NPs) remains to be clearly defined. Conflicting results were reported on the roles of particulate guanylyl cyclase A receptor (pGC-A) and NP clearance receptor (NPRC) in aldosterone inhibition. Furthermore, the functions of protein kinase G (PKG) and phosphodiesterases (PDE) on aldosterone regulation are not clear. Herein, we investigated the molecular mechanism of aldosterone regulation in the human adrenocortical cell line H295R and in mice. We firstly showed that pGC-A mediates aldosterone inhibition. In contrast, with NPRC agonist and antagonist, we showed that NPRC did not inhibit aldosterone. Next, we confirmed that MANP inhibits aldosterone via PDE2, not PKG, with specific agonists, antagonists, siRNA silencing, and fluorescence resonance energy transfer (FRET) experiments. Specifically, MANP suppressed ANGII mediated activation of aldosterone (fold change) MANP+ANGII 3.2±0.1* vs. ANGII 3.8±0.1 (*p<0.05) with IBMX, a PDEs inhibitor and the PDE2 antagonist Bay 60-7550 reversed MANP-mediated aldosterone suppression (IBMX+MANP+ANGII 3.9±0.2 and Bay+MANP+ANGII 4.1±0.1). With PKG agonists and inhibitors, aldosterone levels were not changed. In PDE2 activity FRET studies, aldosterone control was 3.7±0.4 and with MANP 0.9±0.2* supporting PDE2 activation by MANP. Further, the inhibitory effect of PDE2 is mediated by a reduction of intracellular Ca2+ concentration (~22%). We then showed that MANP directly reduced aldosterone synthase CYP11B2 expression in vitro. Lastly, in PDE2 knockout mice (embryonic lethal), embryonic adrenal CYP11B2 expression is markedly increased (wild type: 1±0.2, KO: 2.8±0.5*). Our findings innovatively elucidate the pGC-A/cGMP/PDE2 pathway in aldosterone inhibition by MANP in vitro and in vivo. Additionally, our data also support the development of MANP as a novel ANP analog drug for CVD.
CD274 ( PD-L1 ) Copy Number Changes (Gain) & Response to Immune Checkpoint Blockade Therapy in Carcinomas of the Urinary Tract
Gupta, Sounak , Zhang, Yanming , Tickoo, Satish K. , Fine, Samson W. , Gopalan, Anuradha , Chen, Ying‐Bei , Teo, Min Yuen , Funt, Samuel A. , Bajorin, Dean F. , Ross, Dara S. , Ladanyi, Marc , Cheville, John C. , Solit, David B. , Reuter, Victor E. , Teo, Min Y , Vanderbilt, Chad , Sirintrapun, Sahussapont Joseph , Iyer, Gopa , Rosenberg, Jonathan E , Bochner, Bernard H. , Pietzak, Eugene J , Al-Ahmadie, Hikmat A

Bladder Cancer | August 13, 2021 | Volume: 7 | Issue: 4 | Pages: 395-400

10.3233/blc-201532 | PMID 35071713 Get It

BACKGROUND: Immune checkpoint inhibitors are an important therapeutic option for urothelial carcinoma, but durable responses are achieved in a minority of patients. Identifying pre-treatment biomarkers that may predict response to these therapies or who exhibit intrinsic resistance, is of paramount importance. OBJECTIVE: To explore the prevalence of PD-L1 copy number alteration in urothelial carcinoma and correlate with response to immune checkpoint inhibitors. METHODS: We analyzed a cohort of 1050 carcinomas of the bladder and upper urinary tract that underwent targeted next generation sequencing, prospectively. We assessed PD-L1 protein expression, copy number status (next generation sequencing/FISH), and detailed treatment response. RESULTS: We identified 9 tumors with PD-L1 amplification and 9 tumors with PD-L1 deletion. PD-L1 protein expression was the highest in PD-L1 amplified tumors. Of the 9 patients whose tumors harbored PD-L1 amplification, 6 received immunotherapy with 4 deriving clinical benefit, and 2 achieving durable response. Of the 9 patients whose tumors had PD-L1 copy number losses, 4 received immunotherapy with 3 experiencing disease progression. CONCLUSIONS: PD-L1 copy number alterations may serve as potential biomarkers of response to immunotherapy in urothelial carcinoma patients, if validated in larger cohorts.
Fimepinostat (CUDC‐907) in patients with relapsed/refractory diffuse large B cell and high‐grade B‐cell lymphoma: report of a phase 2 trial and exploratory biomarker analyses
Landsburg, Daniel J. , Ramchandren, Radhakrishnan , Batlevi, Connie Lee , Iyer, Swaminathan P. , Kelly, Kevin R. , Micallef, Ivana N. , Smith, Sonali M. , Stevens, Don A., Alvarez, Mariano J. , Shen, Yao , Bosker, Gideon, Parker, Jefferson, Soikes, Raul, Martinez, Elizabeth , Roemeling, Reinhard von, Martell, Robert E., Oki, Yasuhiro , Landsburg, Daniel J , Barta, Stefan K , Califano, Andrea , Parker, Jefferson

British Journal of Haematology | August 3, 2021 | Volume: 195 | Issue: 2 | Pages: 201-209

10.1111/bjh.17730 | PMID 34341990 Get It

SummaryFimepinostat (CUDC‐907), a first‐in‐class oral small‐molecule inhibitor of histone deacetylase and phosphatidylinositol 3‐kinase, demonstrated efficacy in a phase 1 study of patients with relapsed/refractory (R/R) diffuse large and high‐grade B‐cell lymphomas (DLBCL/HGBL), particularly those with increased MYC protein expression and/orMYCgene rearrangement/copy number gain (MYC‐altered disease). Therefore, a phase 2 study of fimepinostat was conducted in this patient population with 66 eligible patients treated. The primary end‐point of overall response (OR) rate for patients with MYC‐IHC ≥40% (n = 46) was 15%. Subsequently, exploratory pooled analyses were performed including patients treated on both the phase 1 and 2 studies based upon the presence of MYC‐altered disease as well as a biomarker identified by Virtual Inference of Protein activity by Enriched Regulon analysis (VIPER). For these patients with MYC‐altered disease (n = 63), the overall response (OR) rate was 22% with seven responding patients remaining on treatment for approximately two years or longer, and VIPER yielded a three‐protein biomarker classification with positive and negative predictive values of ≥85%. Prolonged durations of response were achieved by patients with MYC‐altered R/R DLBCL/HGBL treated with single‐agent fimepinostat. Combination therapies and/or biomarker‐based patient selection strategies may lead to higher response rates in future clinical trials.
A phase I study of the anaplastic lymphoma kinase inhibitor ceritinib in combination with gemcitabine‐based chemotherapy in patients with advanced solid tumors
Fountzilas, Christos , Adjei, Alex A. , Ghasemi, Mohammad , Groman, Adrienne , Bshara, Wiam , Goey, Andrew K.L. , Wilton, John H., Iyer, Renuka , Adjei, Alex, Ma, Wen Wee, Opyrchal, Mateusz , Evans, Rachel , Attwood, Kristopher M. , Wee, Wen

International Journal of Cancer | July 28, 2021 | Volume: 149 | Issue: 12 | Pages: 2063-2074

10.1002/ijc.33754 | PMID 34319586 Get It

AbstractIn this phase I, dose‐escalation study, we sought to determine the maximum tolerated dose (MTD) of the anaplastic lymphoma kinase/c‐ROS oncogene 1 receptor (ALK/ROS1) inhibitor ceritinib in combination with gemcitabine‐based chemotherapy in patients with advanced solid tumors. Secondary objectives were characterization of the safety profile, pharmacokinetics and preliminary efficacy of these combinations, and identification of potential biomarkers of efficacy. Ceritinib was combined with gemcitabine (Arm 1), gemcitabine/nab‐paclitaxel (Arm 2) or gemcitabine/cisplatin (Arm 3). Drug concentrations in plasma were measured by tandem mass spectrometric detection (LC‐MS/MS). We analyzed archival tumor tissue for ALK, ROS1, hepatocyte growth factor receptor (c‐MET) and c‐Jun N‐terminal kinase (JNK) expression by immunohistochemistry. Arm 2 closed early secondary to toxicity. Twenty‐one patients were evaluable for dose‐limiting toxicity (DLT). There was one DLT in Arm 1 (grade 3 ALT increase) and three DLTs in Arm 3 (grade 3 acute renal failure, grade 3 thrombocytopenia, grade 3 dyspnea). The MTD of ceritinib was determined to be 600 mg (Arm 1) and 450 mg orally daily (Arm 3). Main toxicities were hematologic, constitutional and gastrointestinal as expected by the chemotherapy backbone. The apparent clearance for ceritinib decreased substantially after repeated dosing; cisplatin did not significantly affect the pharmacokinetics of ceritinib. The overall response rate was 20%; the median progression‐free survival was 4.8 months. Three out of five response‐evaluable cholangiocarcinoma patients had clinical benefit. Increased expression of c‐MET was associated with a lack of clinical benefit. Ceritinib in combination with gemcitabine and gemcitabine/cisplatin has a manageable toxicity profile. Further development of this strategy in tumors with ALK or ROS1 fusions is warranted.
Spray cryotherapy prevents need for palliative stenting in patients with esophageal cancer-associated dysphagia
Hanada, Yuri , Leggett, Cadman L. , Iyer, Prasad G. , Linn, Bryan, Mangels-Dick, Tiffany, Wang, Kenneth K, Leggett, Cadman L

Diseases of the Esophagus | July 28, 2021 | Volume: 35 | Issue: 1 | Pages: No page available

10.1093/dote/doab051 | PMID 34318325 Get It

Abstract Background Dysphagia is the most common symptom in advanced esophageal cancer patients. Esophageal stent placement (SP) is a common palliation method but can be associated with significant morbidity. Limited data exist regarding the ability of spray cryotherapy (SC) prolong time to SP. Methods A Mayo Clinic (Rochester, MN) patient database was reviewed for cases with a SC indication of esophageal cancer palliation from 2007–2019. Procedures were performed using a liquid nitrogen SC system to apply 2–5 separate 20 second freeze and 60 second thaw cycles based on tumor characteristics. Primary outcome was time to subsequent palliative SP. Results Of 56 patients (71.4% male, mean age 77.8 ± 10.2 years) who underwent a total of 199 SC sessions (mean 3.6 ± 2.7, range 1–12 per patient), 41 had adenocarcinoma and 15 squamous cell carcinoma (SCC). Overall, 13 patients underwent subsequent SP within a mean duration of 15.7 ± 11.0 months over a mean follow-up duration of 25.6 ± 29.4 months. Treatment did produce stenosis in 16 patients, who required dilation within a mean period of 193.1 ± 294.1 days; notably, 10 patients had a history of preceding malignant strictures requiring dilation. Two patients experienced bleeding requiring transfusion, whereas 1 experienced perforation at the start of SC. Prior chemotherapy and/or radiation was not associated with developing an SC-related complication (risk ratio (RR) 1.5; 95% CI 0.6–3.7, P &gt; 0.4). Conclusions SC appears to be an effective and safe modality to palliate esophageal cancer in appropriate candidates. Majority of patients who undergo SC avoid the need for future SP. If patients eventually require SP, they are able to, on average, defer stenting for &gt;1 year from SC initiation.