Publications by authors named "C Mel Wilcox"

1,230 Publications

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Compensatory post-diuretic renal sodium reabsorption is not a dominant mechanism of diuretic resistance in acute heart failure.

Eur Heart J 2021 Sep 16. Epub 2021 Sep 16.

Department of Internal Medicine, Section of Cardiovascular Medicine, Yale University School of Medicine, 135 College Street, Suite 230, New Haven, CT 06510, USA.

Aims: In healthy volunteers, the kidney deploys compensatory post-diuretic sodium reabsorption (CPDSR) following loop diuretic-induced natriuresis, minimizing sodium excretion and producing a neutral sodium balance. CPDSR is extrapolated to non-euvolemic populations as a diuretic resistance mechanism; however, its importance in acute decompensated heart failure (ADHF) is unknown.

Methods And Results: Patients with ADHF in the Mechanisms of Diuretic Resistance cohort receiving intravenous loop diuretics (462 administrations in 285 patients) underwent supervised urine collections entailing an immediate pre-diuretic spot urine sample, then 6-h (diuretic-induced natriuresis period) and 18-h (post-diuretic period) urine collections. The average spot urine sodium concentration immediately prior to diuretic administration [median 15 h (13-17) after last diuretic] was 64 ± 33 mmol/L with only 4% of patients having low (<20 mmol/L) urine sodium consistent with CPDSR. Paradoxically, greater 6-h diuretic-induced natriuresis was associated with larger 18-h post-diuretic spontaneous natriuresis (r = 0.7, P < 0.001). Higher pre-diuretic urine sodium to creatinine ratio (r = 0.37, P < 0.001) was the strongest predictor of post-diuretic spontaneous natriuresis. In a subgroup of patients (n = 43) randomized to protocol-driven intensified diuretic therapies, the mean diuretic-induced natriuresis increased three-fold. In contrast to the substantial decrease in spontaneous natriuresis predicted by CPDSR, no change in post-diuretic spontaneous natriuresis was observed (P = 0.47).

Conclusion: On a population level, CPDSR was not an important driver of diuretic resistance in hypervolemic ADHF. Contrary to CPDSR, a greater diuretic-induced natriuresis predicted a larger post-diuretic spontaneous natriuresis. Basal sodium avidity, rather than diuretic-induced CPDSR, appears to be the predominant determinate of both diuretic-induced and post-diuretic natriuresis in hypervolemic ADHF.
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http://dx.doi.org/10.1093/eurheartj/ehab620DOI Listing
September 2021

Expanding the arsenal for medical management of vascular ectasias.

Authors:
C Mel Wilcox

Lancet Gastroenterol Hepatol 2021 Sep 8. Epub 2021 Sep 8.

Division of Gastroenterology and Hepatology, University of Alabama at Birmingham, Birmingham, AL 35295, USA. Electronic address:

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http://dx.doi.org/10.1016/S2468-1253(21)00309-5DOI Listing
September 2021

Detecting anchored fish aggregating devices (AFADs) and estimating use patterns from vessel tracking data in small-scale fisheries.

Sci Rep 2021 Sep 9;11(1):17909. Epub 2021 Sep 9.

Commonwealth Scientific and Industrial Research Organisation (CSIRO) Oceans and Atmosphere, Hobart, TAS, 7000, Australia.

Monitoring the use of anchored fish aggregating devices (AFADs) is essential for effective fisheries management. However, detecting the use of these devices is a significant challenge for fisheries management in Indonesia. These devices are continually deployed at large scales, due to large numbers of users and high failure rates, increasing the difficulty of monitoring AFADs. To address this challenge, tracking devices were attached to 34 handline fishing vessels in Indonesia over a month period each. Given there are an estimated 10,000-50,000 unlicensed AFADs in operation, Indonesian fishing grounds provided an ideal case study location to evaluate whether we could apply spatial modeling approaches to detect AFAD usage and fish catch success. We performed a spatial cluster analysis on tracking data to identify fishing grounds and determine whether AFADs were in use. Interviews with fishers were undertaken to validate these findings. We detected 139 possible AFADs, of which 72 were positively classified as AFADs. Our approach enabled us to estimate AFAD use and sharing by vessels, predict catches, and infer AFAD lifetimes. Key implications from our study include the potential to estimate AFAD densities and deployment rates, and thus compliance with Indonesia regulations, based on vessel tracking data.
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http://dx.doi.org/10.1038/s41598-021-97227-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8429724PMC
September 2021

Shoulder Range of Motion Deficits in Youth Throwers Presenting With Elbow Pain.

Sports Health 2021 Aug 20:19417381211036387. Epub 2021 Aug 20.

Andrews Institute for Orthopaedics and Sports Medicine, Gulf Breeze, Florida.

Background: Glenohumeral internal rotation deficit (GIRD) and total arc of motion difference (TAMD) have been associated with elbow injuries in throwing athletes.

Hypothesis: Youth pitchers with elbow pain will have greater GIRD and TAMD compared with youth pitchers without elbow pain.

Study Design: Cross-sectional study.

Level Of Evidence: Level 3.

Methods: Glenohumeral range of motion of 25 consecutive throwing athletes presenting with elbow pain and that of a matched control group of 18 asymptomatic throwing athletes were compared. Bilateral glenohumeral internal rotation, external rotation, and horizontal adduction at 90° were measured and GIRD and TAMD were then calculated. An analysis of variance was performed to compare range of motion between throwers with and without elbow pain.

Results: The average GIRD of the elbow pain group was 32.7° compared with 14.5° in the control group ( < 0.05). The average TAMD in the elbow pain group was 28.3° compared with 6.7° in the control group ( < 0.05). GIRD and TAMD were present in 88% (22 of 25) and 96% (24 of 25) of the elbow pain group versus 33.3% (6 of 18) and 55.6% (10 of 18) of the control group, respectively.

Conclusion: Compared with asymptomatic youth pitchers, those presenting with elbow pain have a statistically significant GIRD and TAMD.

Clinical Relevance: This study suggests that a GIRD and TAMD may predispose youth pitchers to present with symptomatic elbow pain.
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http://dx.doi.org/10.1177/19417381211036387DOI Listing
August 2021

Renal Negative Pressure Treatment as a Novel Therapy for Heart Failure Induced Renal Dysfunction.

Am J Physiol Regul Integr Comp Physiol 2021 08 18. Epub 2021 Aug 18.

Department of Internal Medicine, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT, United States.

Congestion is the primary pathophysiologic lesion in most heart failure (HF) hospitalizations. Renal congestion increases renal tubular pressure, reducing glomerular filtration rate (GFR) and diuresis. Because each nephron is a fluid filled column, renal negative pressure therapy (rNPT) applied to the urinary collecting system should reduce tubular pressure, potentially improving kidney function. We evaluated the renal response to rNPT in congestive HF. Ten anesthetized ∼80 kg pigs underwent instrumentation with bilateral renal pelvic JuxtaFlow® catheters. GFR was determined by iothalamate clearance (mGFR) and renal plasma flow (RPF) by para-aminohippurate clearance. Each animal served as its own control with randomization of L vs. R kidney to -30mmHg rNPT or no rNPT mGFR and RPF were measured simultaneously from the rNPT and no rNPT kidney. Congestive HF was induced via cardiac tamponade maintaining central venous pressure at 20-22.5mmHg throughout the experiment. Prior to HF induction, rNPT increased natriuresis, diuresis, and mGFR compared with the control kidney (p<0.001 for all). Natriuresis, diuresis, and mGFR, decreased following HF (p<0.001 for all) but were higher in rNPT kidney vs. control (p<0.001 for all). RPF decreased during HF (p<0.001) without significant differences between rNPT treatments. During HF the rNPT kidney had similar diuresis and natriuresis (p>0.5 for both), and higher fractional excretion of sodium (p=0.001) compared with the non-rNPT kidney in the no-HF period. In conclusion, rNPT resulted in significantly increased diuresis, natriuresis, and mGFR, with or without experimental HF. rNPT improved key renal parameters of the congested cardio-renal phenotype.
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http://dx.doi.org/10.1152/ajpregu.00115.2021DOI Listing
August 2021
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