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410 citation(s) found for "Nair, R".

Impact of diabetes on ceramides in skeletal muscle subcellular fractions
Blachnio‐Zabielski, Agnieszka Urszula, Persson, Xuan‐Mai, Jensen, Michael D. , Zabielski, Piotr , Lanza, Ian R. , Nair, K. Sreekumaran

The FASEB Journal | June 15, 2021 | Volume: 24 | Issue: S1 | Pages: No page available

10.1096/fasebj.24.1_supplement.783.3 Get It

Insulin has been shown to have major impact on muscle mitochondrial function. Recent data show that ceramide can decrease oxygen consumption and ATP production in isolated mitochondria. The aim of the present study was to determine whether insulin deficiency alters ceramide (CER) and its metabolites ‐ sphinganine (SPA), sphingosine (SPH) and sphingosine‐1‐phosphate (S1P) ‐ in mitochondrial (mt) and sarcoplasmic (src) fractions from quadriceps muscle of streptozotocin‐diabetic C57BL/6 male mice. We studied non‐diabetic controls (C); diabetic, insulin‐treated (D+); and diabetic, insulin‐deprived (D−). D− and D+ group received LinBit insulin implants, whereas C group received blank implants. Implants from D− group were removed 7 days prior to sacrifice. CER and its metabolites were measured in a tandem mass spectrometer connected to a UPLC system. Insulin deprivation increased CER in muscle src although decreased in mt. Insulin treatment normalized CER content in src, but further lowered CER content in mt, which was accompanied by elevation in mitochondrial SPH content. Changes in SPA and S1P levels in both the src and mt were non‐significant. In conclusion, diabetes and insulin have profound effects on CER concentrations in muscle subcellular fractions. C D− D+ src mt src mt src mt SPA Mean 0.34 nd 0.32 nd 0.34 nd SEM ±0.04 ±0.02 ±0.04 SPH Mean 0.44 1.63 0.61 2.15 0.47 2.55 SEM ±0.07 ±0.23 ±0.10 ±0.14 ±0.03 ±0.21 S1P Mean 0.32 1.14 0.27 1.06 0.23 0.91 SEM ±0.03 ±0.2 ±0.05 ±0.14 ±0.01 ±0.1 CER Mean 85.7 326.0 162.5 267.3 93.0 199.7 SEM ±17.4 ±38.4 ±19.8 ±24.0 ±4.4 ±11.2
Myosin loss and muscle wasting in an experimental ICU model: Underlying mechanisms
Diaz, Monica Llano, Gustafson, Ann‐Marie, Dworkin, Barry R., Nair, Sreekumaran K, Larsson, Lars , Ochala, Julien , Nair, Sreekumaran K, Gautel, Mathias

The FASEB Journal | June 15, 2021 | Volume: 24 | Issue: S1 | Pages: No page available

10.1096/fasebj.24.1_supplement.1046.3 Get It

The muscle wasting and impaired muscle function associated with critical llness in ICU patients have negative consequences for recovery from primary disease, but are also the most persistent and debilitating of problems for ICU survivors years after hospital discharge. This study aims at improving our understanding of the mechanisms underlying the muscle wasting in ICU patients by conducting time‐resolved analyses of skeletal muscle structure and function together with measurements of protein synthesis rate, myofibrillar protein and gene expression and intracellular signaling in response to post‐synaptic block of neuromuscular transmission (NMB), sedation, mechanical ventilation and muscle unloading at durations varying from hours to two wks by using a unique experimental rat ICU model. Skeletal muscle structure and function were well maintained during the first four days, followed by a dramatic and progressive decline in muscle size and function. The preferential loss of the molecular motor protein myosin and impaired forcegenerating capacity (specif force) are the major causes underlying the impaired skeletal muscle function in the ICU model. Muscle unloading due to lack of weightbearing (external unloading) and muscle membrane depolarization (internal unloading) are forwarded as very important underlying factors. Supported by the Sweish Research Council and AFM
Short‐ and mid‐term outcomes in percutaneous mitral valve replacement using balloon expandable valves
Eng, Marvin H. , Kargoli, Faraj , Wang, Dee Dee , Frisoli, Tiberio , Villablanca, Pedro, Nemeh, Hassan, Guerrero, Mayra , O’Neill, Brian , Wyman, Janet , Guerrero, Mayra E , O'Neill, Brian P , Wang, Dee Dee , Lee, James C. , Villablanca, Pedro, Greenbaum, Adam B. , O’Neill, William W.

Catheterization and Cardiovascular Interventions | June 9, 2021 | Volume: 98 | Issue: 6 | Pages: 1193-1203

10.1002/ccd.29783 | PMID 34106514 Get It

AbstractBackgroundDue to elevated surgical risk, transcatheter mitral valve replacement (TMVR) is used as an alternative for treating failed bioprosthetic valves, annuloplasty repairs and mitral annular calcification (MAC). We report the procedural and longitudinal outcomes for each subtype: Mitral valve‐in‐valve (MVIV), mitral valve‐in‐ring (MViR), and valve‐in‐MAC (ViMAC).MethodsConsecutive patients undergoing TMVR from October 2013 to December 2019 were assessed. Patients at high risk for left ventricular outflow tract obstruction had either alcohol septal ablation or intentional laceration of the anterior leaflet (LAMPOON).ResultsEight‐eight patients underwent TMVR; 38 MViV, 31 MViR, and 19 ViMAC procedures were performed. The median Society of Thoracic Surgery 30‐day predicted risk of mortality was 8.2% (IQR 5.2, 19.9) for all. Sapien 3 (78%) and transseptal access (98%) were utilized in most cases. All‐cause in‐hospital mortality, technical, and procedural success were 8%, 83%, and 66% respectively. Median follow up was 1.4 years (IQR 0.5–2.9 years) and overall survival was 40% at 4 years. Differential survival rates were observed with MViV doing the best, followed by MViR and ViMAC having a <20% survival at 4 years. After adjusting for co‐variates, MViV procedure was the strongest predictor of survival (HR 0.24 [95% CI 0.079–0.7]).ConclusionTMVR is performed in at high‐risk patients with attenuated long‐term survival. MViV has the best success and survival rate, but long‐term survival in MViR and ViMAC is guarded.
Correlation of Chronic Histologic Changes on Preimplantation Frozen Section Biopsy With Transplant Outcomes After Deceased Donor Kidney Transplantation
Ninan, Jacob, Smith, Maxwell L., Mathur, Amit K., Harbell, Jack W., Jadlowiec, Caroline C., Nair, Sumi Sukumaran, Moss, Adyr, Reddy, Kunam S., Heilman, Raymond L., Ninan, Jacob, Smith, Maxwell L., Mathur, Amit K., Harbell, Jack W., Jadlowiec, Caroline C., Nair, Sumi Sukumaran, Moss, Adyr, Reddy, Kunam S., Heilman, Raymond L.

Archives of Pathology & Laboratory Medicine | June 4, 2021 | Volume: 146 | Issue: 2 | Pages: 205-212

10.5858/arpa.2020-0675-oa | PMID 34086859 Get It

Context.— It is unclear if preimplantation frozen section biopsy correlates with outcomes after deceased donor kidney transplantation. Objective.— To assess if chronic histologic changes on the preimplant frozen section correlates with graft loss and estimated glomerular filtration rate independently of kidney donor profile index (KDPI). Design.— Seven hundred three preimplantation biopsies were reviewed and a Banff sum score was calculated using glomerular sclerosis, interstitial fibrosis, vascular intimal thickening, and arteriolar hyalinosis. The posttransplant outcomes were compared for preimplantation biopsy Banff sum 0-1, 2-3, and 4-9. The cohort was also stratified by KDPI 85 or less versus more than 85. Results.— For the entire biopsy cohort, graft survival, estimated glomerular filtration rate at 1 year, and chronic changes on a 1-year posttransplant biopsy were superior in the group with preimplantation Banff sum 0-1. After stratifying by KDPI, the Banff sum no longer correlated with graft survival. In a univariate mode, using the Banff sum score as a continuous variable, a higher Banff sum score was significantly associated with graft failure (P = .03); however, after adjusting the KDPI, the Banff sum score no longer correlated with graft failure (P = .45). The 1-year estimated glomerular filtration rate and 1-year biopsy changes were superior in the group with Banff sum 0-1 only in the cohort with KDPI 85 or less. Conclusions.— In donor kidneys used for transplant, preimplantation biopsy chronic changes correlate with estimated glomerular filtration rate and biopsy findings at 1 year, but biopsies with mostly mild chronicity and Banff sum scores less than or equal to 5 did not impact graft survival beyond KDPI.
Association of plasma adiponectin with tumor infiltrating lymphocytes and survival in patients with stage III colon cancer (NCCTG N0147; Alliance).
Smyrk, Thomas C. , Goldberg, Richard M. , Cohen, Steven J., Kahlenberg, Morton S., Nair, Suresh , Shields, Anthony F. , Jahagirdar, Balkrishna, Foster, Nathan R. , Sinicrope, Frank A. , Shi, Qian , Gill, Sharlene , Jacobson, Sawyer , Pollak, Michaël , Alberts, Steven R.

Journal of Clinical Oncology | June 2, 2021 | Volume: 39 | Issue: 15_suppl | Pages: 3591-3591

10.1200/jco.2021.39.15_suppl.3591 Get It

3591 Background: Adiponectin is a peptide hormone exclusively secreted by adipocytes that plays a role in immune regulation and in the host inflammatory response to cancer. We examined postsurgical adiponectin levels in relationship to tumor infiltrating lymphocytes (TILs), clinicopathological features, vitamin D status, and patient survival in participants in a phase 3 trial of adjuvant chemotherapy. Methods: Plasma adiponectin and 25-hydroxyvitamin D [25(OH)D] were analyzed by radioimmunoassay in 600 patients with stage III colon carcinoma who received adjuvant FOLFOX +/- cetuximab. TIL densities were determined at light microscopy in routine histopathological sections. The associations between adiponectin and 25(OH)D, TILs, other factors were evaluated by Fisher’s Exact, Chi-squared, t-test, and Kruskal-Wallis tests where appropriate. The association between adiponectin or 25(OH)D with disease-free survival (DFS), time to recurrence (TTR) and overall survival (OS) were evaluated by multivariable Cox regression, adjusting for body mass index (BMI), race, T, N stage, performance status, tumor location, TILs, BRAF/KRAS, and mismatch repair status. Results: A statistically significant and inverse association between adiponectin level and BMI was observed with lower levels found with obesity (BMI > 30 kg/m2) [p < 0.001]. The level of adiponectin was significantly lower in men vs women (p < 0.001), in blacks vs whites or Asians (p < 0.032), and in patients with fewer regional lymph node metastases (N1 vs N2 stage, p = 0.011). A significantly lower level of adiponectin was found in patients whose tumors had high vs low TIL densities (p = 0.040), but was unrelated to 25(OH)D. Insufficiency of 25(OH)D ( < 30 ng/ml) was detected in 291 (49%) of patients and was not associated with TILs. By multivariable analysis, adiponectin was not associated significantly with patient DFS (HRadj= 0.98, 95% CI 0.74-1.29, padj= 0.88) nor with OS nor time-to-recurrence (TTR). TIL densities were significantly prognostic, but 25(OH)D was not (DFS: HRadj= 1.12, 95% CI 0.85-1.47, padj= 0.44). No significant interaction was observed for adiponectin with TILs for the association with DFS. Conclusions: Lower adiponectin levels were associated with significantly increased TIL densities in colon cancers, indicating an enhanced anti-tumor immune response. In contrast to TILs, adiponectin was not independently associated with patient outcome. Nearly one-half of stage III patients were vitamin D insufficient, although 25(OH)D was not prognostic.
Real world outcomes using 20 mm balloon expandable SAPIEN 3/ultra valves compared to larger valves (23, 26, and 29 mm)–a propensity matched analysis
Eng, Marvin H. , Abbas, Amr E. , Wang, Dee Dee , Eleid, Mackram F. , Wang, Dee Dee , Eleid, Mackram F , Hahn, Rebecca T , Lee, James , O’Neill, William W.

Catheterization and Cardiovascular Interventions | May 13, 2021 | Volume: 98 | Issue: 6 | Pages: 1185-1192

10.1002/ccd.29756 | PMID 33984182 Get It

AbstractObjective/BackgroundSmall balloon expandable valves have higher echocardiographic transvalvular gradients and rates of prosthesis‐patient mismatch (PPM) compared to larger valves. However, the impact of these echocardiographic findings on clinical outcomes is unknown. We sought to determine the clinical outcomes of 20 mm SAPIEN 3 (S3 BEV) compared to larger S3 BEV in relation to echocardiographic hemodynamics.MethodsUsing the STS/ACC transcatheter valve registry, we performed a propensity‐matched comparison of patients undergoing treatment of native aortic valve stenosis using transfemoral, balloon‐expandable implantation of 20 mm and ≥ 23 mm S3 BEVs. Baseline and procedure characteristics, echocardiographic variables and survival were analyzed. Multivariable logistic regression was used to identify predictors of 1‐year mortality.ResultsAfter propensity matching of the 20 mm and ≥ 23 mm SAPIEN 3 valves, 3,931 pairs with comparable baseline characteristics were identified. Small valves were associated with significantly higher echocardiographic gradients at discharge (15.7 ± 7.1 mmHg vs. 11.7 ± 5.5 mmHg, p < 0.0001) and severe PPM rates (21.5% vs. 9.7%, p < 0.0001). There was no significant difference in 1‐year all‐cause mortality (20 mm: 13.0% vs. ≥23 mm: 12.7%, p = 0.72) or other major adverse event rates and outcomes between the two cohorts. Based on a multivariable analysis, elevated discharge mean gradient (>20 mmHg), severe PPM and the use of 20 mm versus ≥23 mm were not independent predictors of 1‐year mortality.ConclusionSAPIEN 3 20 mm valves were associated with higher echocardiographic gradients, and severe PPM rates compared to larger valves but these factors were not associated with significant differences in 1‐year all‐cause mortality or rehospitalization.
Surface Roughness of Titanium Orthopedic Implants Alters the Biological Phenotype of Human Mesenchymal Stromal Cells
Trousdale, William H. , Thaler, Roman , Xu, Wei , Denbeigh, Janet M. , Nair, Asha, Kocher, Jean‐Pierre , Dudakovic, Amel , Berry, Daniel J., Cohen, Robert C., Lewallen, David G. , Wijnen, André J. van , Berry, Daniel J. , Lewallen, Eric A. , Xu, Wei , van Wijnen, Andre J , Berry, Daniel J , Yao, Jie , Berry, Daniel J., Abdel, Matthew P.

Tissue Engineering Part A | May 12, 2021 | Volume: 27 | Issue: 23-24 | Pages: 1503-1516

10.1089/ten.tea.2020.0369 | PMID 33975459 Get It

Primary Outcome Evaluation of a Next-Generation Left Atrial Appendage Closure Device
Kar, Saibal , Doshi, Shephal K. , Sadhu, Ashish, Horton, Rodney , Osorio, José , Stone, James, Shah, Manish H. , Dukkipati, Srinivas R. , Adler, Stuart W., Kim, Jamie , Wazni, Oussama M. , Price, Mathew J., Holmes, David R. , Shipley, Robert D., Gordon, Nicole, Allocco, Dominic J. , Investigators, On behalf of the PINNACLE FLX, Kar, Saibal , Ellis, Christopher R. , Nair, Devi G , Asch, Federico M. , Reddy, Vivek Y. , Investigators, On behalf of the PINNACLE FLX

Circulation | April 6, 2021 | Volume: 143 | Issue: 18 | Pages: 1754-1762

10.1161/circulationaha.120.050117 | PMID 33820423 Get It

Background: Left atrial appendage (LAA) occlusion provides an alternative to oral anticoagulation for thromboembolic risk reduction in patients with nonvalvular atrial fibrillation. Since regulatory approval in 2015, the WATCHMAN device has been the only LAA closure device available for clinical use in the United States. The PINNACLE FLX study (Protection Against Embolism for Nonvalvular AF Patients: Investigational Device Evaluation of the Watchman FLX LAA Closure Technology) evaluated the safety and effectiveness of the next-generation WATCHMAN FLX LAA closure device in patients with nonvalvular atrial fibrillation in whom oral anticoagulation is indicated, but who have an appropriate rationale to seek a nonpharmaceutical alternative. Methods: This was a prospective, nonrandomized, multicenter US Food and Drug Administration study. The primary safety end point was the occurrence of one of the following events within 7 days after the procedure or by hospital discharge, whichever was later: death, ischemic stroke, systemic embolism, or device- or procedure-related events requiring cardiac surgery. The primary effectiveness end point was the incidence of effective LAA closure (peri-device flow ≤5 mm), as assessed by the echocardiography core laboratory at 12-month follow-up. Results: A total of 400 patients were enrolled. The mean age was 73.8±8.6 years and the mean CHA 2 DS 2 -VASc score was 4.2±1.5. The incidence of the primary safety end point was 0.5% with a 1-sided 95% upper CI of 1.6%, meeting the performance goal of 4.2% ( P <0.0001). The incidence of the primary effectiveness end point was 100%, with a 1-sided 95% lower CI of 99.1%, again meeting the performance goal of 97.0% ( P <0.0001). Device-related thrombus was reported in 7 patients, no patients experienced pericardial effusion requiring open cardiac surgery, and there were no device embolizations. Conclusions: LAA closure with this next-generation LAA closure device was associated with a low incidence of adverse events and a high incidence of anatomic closure. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02702271.
Integrated Proteomic and Phosphoproteomics Analysis of DKK3 Signaling Reveals Activated Kinase in the Most Aggressive Gallbladder Cancer
Gondkar, Kirti , Joshi, Neha , Pandey, Akhilesh , Kumar, Prashant , Kumar, Prashant , Pandey, Akhilesh , Joshi, Neha S , Sathe, Gajanan , Nair, Bipin G.

Cells | February 28, 2021 | Volume: 10 | Issue: 3 | Pages: 511

10.3390/cells10030511 | PMID 33670899 Get It

DKK3 is a secreted protein, which belongs to a family of Wnt antagonists and acts as a potential tumor suppressor in gallbladder cancer. To further understand its tumor suppressor functions, we overexpressed DKK3 in 3 GBC cell lines. We have employed high-resolution mass spectrometry and tandem mass tag (TMT) multiplexing technology along with immobilized metal affinity chromatography to enrich phosphopeptides to check the downstream regulators. In this study, we reported for the first time the alteration in the phosphorylation of 14 kinases upon DKK3 overexpression. In addition, we observed DKK3 induced hyper phosphorylation of 2 phosphatases: PPP1R12A and PTPRA, which have not been reported previously. Canonical pathway analysis of altered molecules indicated differential enrichment of signaling cascades upon DKK3 overexpression in all the 3 cell lines. Protein kinase A signaling, Sirtuin signaling pathway, and Cell Cycle Control of Chromosomal Replication were observed to be differentially activated in the GBC cell lines. Our study revealed, DKK3 overexpression has differential effect based on the aggressive behavior of the cell lines. This study expands the understanding of DKK3-mediated signaling events and can be used as a primary factor for understanding the complex nature of this molecule.
Brain functions and cognition on transient insulin deprivation in type 1 diabetes
Creo, Ana L. , Cortes, Tiffany , Huebner, Andrea R., Dasari, Surendra , Tillema, Jan-Mendelt , Lteif, Aida, Klaus, Katherine A. , Ruegsegger, Gregory N. , Kudva, Yogish C. , Petersen, Ronald C. , Jo, Hang Joon , Tillema, Jan‐Mendelt , Port, John D. , Nair, K. Sreekumaran

JCI Insight | February 9, 2021 | Volume: 6 | Issue: 5 | Pages: No page available

10.1172/jci.insight.144014 | PMID 33561011 Get It

BACKGROUND Type 1 diabetes (T1D) is a risk factor for dementia and structural brain changes. It remains to be determined whether transient insulin deprivation that frequently occurs in insulin-treated individuals with T1D alters brain function. METHODS We therefore performed functional and structural magnetic resonance imaging, magnetic resonance spectroscopy, and neuropsychological testing at baseline and following 5.4 ± 0.6 hours of insulin deprivation in 14 individuals with T1D and compared results with those from 14 age-, sex-, and BMI-matched nondiabetic (ND) participants with no interventions. RESULTS Insulin deprivation in T1D increased blood glucose, and β-hydroxybutyrate, while reducing bicarbonate levels. Participants with T1D showed lower baseline brain N-acetyl aspartate and myo-inositol levels but higher cortical fractional anisotropy, suggesting unhealthy neurons and brain microstructure. Although cognitive functions did not differ between participants with T1D and ND participants at baseline, significant changes in fine motor speed as well as attention and short-term memory occurred following insulin deprivation in participants with T1D. Insulin deprivation also reduced brain adenosine triphosphate levels and altered the phosphocreatine/adenosine triphosphate ratio. Baseline differences in functional connectivity in brain regions between participants with T1D and ND participants were noted, and on insulin deprivation further alterations in functional connectivity between regions, especially cortical and hippocampus-caudate regions, were observed. These alterations in functional connectivity correlated to brain metabolites and to changes in cognition. CONCLUSION Transient insulin deprivation therefore caused alterations in executive aspects of cognitive function concurrent with functional connectivity between memory regions and the sensory cortex. These findings have important clinical implications, as many patients with T1D inadvertently have periods of transient insulin deprivation. TRIAL REGISTRATION ClinicalTrials.gov NCT03392441. FUNDING Clinical and Translational Science Award (UL1 TR002377) from the National Center for Advancing Translational Science; NIH grants (R21 AG60139 and R01 AG62859); the Mayo Foundation.