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Mara, Kristin C

0000-0002-8783-0191

Mayo Clinic

Mayo Clinic

Citations 172

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Hepatology | January 4, 2020 | Volume: 72 | Issue: 1 | Pages: 362-363

10.1002/hep.31097 | PMID 31901147

Modernizing Storage Conditions for Fresh Osteochondral Allografts by Optimizing Viability at Physiologic Temperatures and Conditions

CARTILAGE | November 28, 2019 | Volume: 13 | Issue: 1_suppl | Pages: 280S-292S

10.1177/1947603519888798 | PMID 31777278

Objective. Osteochondral allograft (OCA) transplantation has demonstrated good long-term outcomes in treatment of cartilage defects. Viability, a key factor in clinical success, decreases with peri-implantation storage at 4°C during pathogen testing, matching logistics, and transportation. Modern, physiologic storage conditions may improve viability and enhance outcomes. Design. Osteochondral specimens from total knee arthroplasty patients (6 males, 5 females, age 56.4 ± 2.2 years) were stored in media and incubated at normoxia (21% O 2 ) at 22°C or 37°C, and hypoxia (2% O 2 ) at 37°C. Histology, live-dead staining, and quantitative polymerase chain reaction (qPCR) was performed 24 hours after harvest and following 7 days of incubation. Tissue architecture, cell viability, and gene expression were analyzed. Results. No significant viability or gene expression deterioration of cartilage was observed 1-week postincubation at 37°C, with or without hypoxia. Baseline viable cell density (VCD) was 94.0% ± 2.7% at day 1. At day 7, VCD was 95.1% (37°C) with normoxic storage and 92.2% (37°C) with hypoxic storage ( P ≥ 0.27). Day 7 VCD (22°C) incubation was significantly lower than both the baseline and 37°C storage values (65.6%; P < 0.01). COL1A1, COL1A2, and ACAN qPCR expression was unchanged from baseline ( P < 0.05) for all storage conditions at day 7, while CD163 expression, indicative of inflammatory macrophages and monocytes, was significantly lower in the 37°C groups ( P < 0.01). Conclusion. Physiologic storage at 37°C demonstrates improved chondrocyte viability and metabolism, and maintained collagen expression compared with storage at 22°C. These novel findings guide development of a method to optimize short-term fresh OCA storage, which may lead to improved clinical results.
Multiparametric Magnetic Resonance Elastography Improves the Detection of NASH Regression Following Bariatric Surgery

Hepatology Communications | November 5, 2019 | Volume: 4 | Issue: 2 | Pages: 185-192

10.1002/hep4.1446 | PMID 32025604

Disease monitoring in nonalcoholic steatohepatitis (NASH) is limited by absence of noninvasive biomarkers of disease regression or progression. We aimed to examine the role of multiparametric three‐dimensional magnetic resonance elastography (3D‐MRE) and magnetic resonance imaging proton density fat fraction (MRI‐PDFF) in the detection of NASH regression after interventions. This is a single‐center prospective clinical trial of 40 patients who underwent bariatric surgery. Imaging and liver biopsies were obtained at baseline and 1 year after surgery. The imaging protocol consisted of multifrequency 3D‐MRE to determine the shear stiffness at 60 Hz and damping ratio at 40 Hz, and MRI‐PDFF to measure the fat fraction. A logistic regression model including these three parameters was previously found to correlate with NASH. We assessed the model performance in the detection of NASH resolution after surgery by comparing the image‐predicted change in NAFLD activity score (delta NAS) to the histologic changes. A total of 38 patients (median age 43, 87% female, 30 of 38 with NAS ≥ 1, and 13 of 38 with NASH) had complete data at 1 year. The NAS decreased in all subjects with NAS ≥ 1 at index biopsy, and NASH resolved in all 13. There was a strong correlation between the predicted delta NAS by imaging and the delta NAS by histology (r = 0.73, P < 0.001). The strength of correlation between histology and the predicted delta NAS using single conventional parameters, such as the fat fraction by MRI‐PDFF or shear stiffness at 60 Hz by MRE, was r = 0.69 (P < 0.001) and r = 0.43 (P = 0.009), respectively. Conclusion: Multiparametric 3D‐MRE and MRI‐PDFF can detect histologic changes of NASH resolution after bariatric surgery. Studies in a nonbariatric setting are needed to confirm the performance as a composite noninvasive biomarker for longitudinal NASH monitoring.
Unfractionated heparin infusion for treatment of venous thromboembolism based on actual body weight without dose capping

Vascular Medicine | October 18, 2019 | Volume: 25 | Issue: 1 | Pages: 47-54

10.1177/1358863x19875813 | PMID 31623539

Controversy exists regarding the use of dose capping of weight-based unfractionated heparin (UFH) infusions in obese and morbidly obese patients. The primary objective of this study was to compare time to first therapeutic activated partial thromboplastin time (aPTT) in hospitalized patients receiving UFH for acute venous thromboembolism (VTE) among three body mass index (BMI) cohorts: non-obese (< 30 kg/m 2 ), obese (30–39.9 kg/m 2 ), and morbidly obese (⩾ 40 kg/m 2 ). In this single-center, retrospective cohort study, patients were included if they ⩾ 18 years of age, had a documented VTE, and were on an infusion of UFH for at least 24 hours. Weight-based UFH doses were calculated using actual body weight. A total of 423 patients met the inclusion criteria, with 230 (54.4%), 146 (34.5%), and 47 (11.1%) patients in the non-obese, obese, and morbidly obese cohorts, respectively. Median times to therapeutic aPTT were 16.4, 16.6, and 17.1 hours in each cohort. Within 24 hours, the cumulative incidence rates for therapeutic aPTT were 70.7% for the non-obese group, 69.9% for the obese group, and 61.7% for the morbidly obese group (obese vs non-obese: HR = 1.02, 95% CI: 0.82–1.26, p = 0.88; morbidly obese vs non-obese: HR = 0.87, 95% CI: 0.62–1.21, p = 0.41). There was no significant difference in major bleeding events between BMI groups (obese vs non-obese, p = 0.91; morbidly obese vs non-obese, p = 0.98). Based on our study, heparin dosing based on actual body weight without a dose cap is safe and effective.
Women With Nonalcoholic Fatty Liver Disease Lose Protection Against Cardiovascular Disease: A Longitudinal Cohort Study

American Journal of Gastroenterology | October 2, 2019 | Volume: 114 | Issue: 11 | Pages: 1764-1771

10.14309/ajg.0000000000000401 | PMID 31577570

OBJECTIVES: Cardiovascular (CV) disease is the top cause of mortality in patients with nonalcoholic fatty liver disease (NAFLD). Female sex is protective against CV disease. We aimed to determine whether female sex remains a protective factor against CV disease (myocardial infarction, angina, and stroke) in NAFLD. METHODS: We identified all adults diagnosed with NAFLD in Olmsted County, Minnesota, between 1997 and 2014 and selected an age- and sex-matched (1:4) referent cohort from the general population. NAFLD was ascertained using a code-based algorithm with high validity tested by medical record review. The impact of female sex on incident CV events was examined using Cox proportional hazards regression analysis stratified by standard clinical risk factors. RESULTS: A total of 3,869 NAFLD and 15,209 age- and sex-matched referent subjects were identified. After a median follow-up time of 7 (range 1–20) years, 3,851 CV events were recorded. Female sex was protective for ischemic CV events in the general population (hazard ratio = 0.71, 95% confidence interval 0.62–0.80, P < 0.001), but the impact was significantly diminished among those with NAFLD (hazard ratio = 0.90, 95% confidence interval 0.74–1.08, P = 0.25), even after stratification by time-dependent CV risk factors and control for diagnostic testing (liver enzymes and ultrasound) during routine medical evaluations, as a surrogate of access to care. Among those with NAFLD, excess events were higher in women than in men: CV disease (18% vs 9%) and mortality (9% vs 6%). DISCUSSION: Women with NAFLD lose the CV protection conferred by the female sex, and their risk is underestimated by current estimating methods in clinical practice.
Iron deficiency anemia associated with extracorporeal photopheresis: A retrospective analysis

Journal of Clinical Apheresis | August 22, 2019 | Volume: 34 | Issue: 6 | Pages: 666-671

10.1002/jca.21744 | PMID 31436854

AbstractBackgroundExtracorporeal photopheresis (ECP) is associated with few adverse effects. We have anecdotally noted patients treated with long‐term ECP develop iron deficiency anemia (IDA).MethodsWe performed a retrospective chart review of adult patients who received ECP for any indication at Mayo Clinic Rochester and Mayo Clinic Arizona. The primary objective was to describe the cumulative incidence of IDA at 1 year of ECP therapy.ResultsA total of 123 patients were eligible for analysis. Graft‐vs‐host disease was the most common indication for ECP (n = 76, 61.8%). At 1 year of ECP therapy, the cumulative incidence of IDA was 24.1% (95% CI, 14.2%‐32.9%). At 5 years, the cumulative incidence of IDA was 68.3% (95% CI, 38%‐83.8%). Risk factors for the development of IDA included: cumulative number of ECP sessions (HR 1.34, 95% CI, 1.05‐1.73 per 10 additional sessions, P = .022), an indication for ECP of solid organ transplant rejection (compared to cutaneous T‐cell lymphoma, HR 5.46, 95% CI, 2.06‐14.49, P < .001), and proton pump inhibitor use at baseline (HR 2.15, 95% CI, 1.1‐4.21, P = .03). Iron supplementation was initiated in 29 of 37 evaluable patients who developed IDA, with a cumulative incidence of supplementation in 77.2% patients within 3 months of recognition of IDA (95% CI, 55.8%‐88.3%). Hemoglobin normalized in 50.1% of patients started on iron supplementation for IDA within 7 months (95% CI, 25.2%‐66.7%).ConclusionsIron deficiency anemia is common in patients receiving long‐term ECP and occurs throughout ECP therapy. IDA resolved with iron supplementation in half of patients.
Diabetes Is Associated With Increased Risk of Hepatocellular Carcinoma in Patients With Cirrhosis From Nonalcoholic Fatty Liver Disease

Hepatology | July 16, 2019 | Volume: 71 | Issue: 3 | Pages: 907-916

10.1002/hep.30858 | PMID 31309602

Diabetes increases the risk of liver disease progression and cirrhosis development in patients with nonalcoholic steatohepatitis (NASH). The association between diabetes and the risk of hepatocellular carcinoma (HCC) in NASH patients with cirrhosis is not well quantified. All patients with the diagnosis of NASH cirrhosis seen at Mayo Clinic Rochester between January 2006 and December 2015 were identified. All adult liver transplant registrants with NASH between 2004 and 2017 were identified using the United Network for Organ Sharing (UNOS)/Organ Procurement and Transplantation registry for external validation. Cox proportional hazard analysis was performed to investigate the association between diabetes and HCC risk. Among 354 Mayo Clinic patients with NASH cirrhosis, 253 (71%) had diabetes and 145 (41%) were male. Mean age at cirrhosis evaluation was 62. During a median follow‐up of 47 months, 30 patients developed HCC. Diabetes was associated with an increased risk of developing HCC in univariate (hazard ratio [HR] = 3.6; 95% confidence interval [CI] = 1.1‐11.9; P = 0.04) and multivariable analysis (HR = 4.2; 95% CI = 1.2‐14.2; P = 0.02). In addition, age (per decade, HR = 1.8; 95% CI = 1.2‐2.6; P < 0.01) and low serum albumin (HR = 2.1; 95% CI = 1.5‐2.9; P < 0.01) were significantly associated with an increased risk of developing HCC in multivariable analysis. Other metabolic risk factors, including body mass index, hyperlipidemia, and hypertension, were not associated with HCC risk. Among UNOS NASH registrants (N = 6,630), 58% had diabetes. Diabetes was associated with an increased risk of developing HCC in univariate (HR = 1.4; 95% CI = 1.1‐1.8; P < 0.01) and multivariable (HR = 1.3; 95% CI = 1.0‐1.7; P = 0.03) analysis. Conclusion: Diabetes is associated with an increased risk of HCC in patients with NASH cirrhosis.
QT prolongation in patients with acute leukemia or high-risk myelodysplastic syndrome prescribed antifungal prophylaxis during chemotherapy-induced neutropenia

Leukemia & Lymphoma | July 12, 2019 | Volume: 60 | Issue: 14 | Pages: 3512-3520

10.1080/10428194.2019.1639165 | PMID 31298598

The impact of Helicobacter pylori on the presence of Barrett's esophagus in Azerbaijan, a high-prevalence area of infection

Diseases of the Esophagus | June 8, 2019 | Volume: 32 | Issue: 11 | Pages: No page available

10.1093/dote/doz053 | PMID 31175364

SUMMARY There is a strong evidence that Helicobacter pylori infection is inversely associated with Barrett's esophagus. In a high-prevalence region of H. pylori, low rates of esophageal cancer and its precursor BE may indicate its preventive effect. The aim of this study is to determine the impact of H. pylori on characteristics of Barrett's esophagus. A total of 3317 outpatient upper endoscopy reports from 2013 to 2015 from an urban center in Azerbaijan from all patients with dyspepsia were retrospectively analyzed for patients with Barrett's esophagus. This was matched in a 1:2 ratio to age and gender matched control patients without Barrett's esophagus. The prevalence of H. pylori on Barrett's esophagus and the randomly selected control group were compared. There were 83 patients with BE and 167 control group cases. Biopsy-proven BE was diagnosed in 83 patients: 39 (47%) females, with mean age 43.1 ± 13.3 years. Of these, 13 (15.7%) had long segment and 70 (84.3%) had short segment Barrett's esophagus. A control group included 167 patients: 78 (46.7%) females, with mean age (45.8 ± 13.9). All patients were Caucasians. The rates of gastric inflammation, the presence of atrophy, and intestinal metaplasia in gastric specimens did not differ in patients versus controls. The prevalence of H. pylori was determined as 63.2% in male and 61.5 in female groups (odd ratio (OR) = 0.99 95%CI 0.97, 1.01; P = 0.22). Inflammation of gastric mucosa was strongly associated with the infection (67% vs. 33%; OR = 4.46 95% CI: 2.01, 9.92, P &lt; 0.001). Atrophy was noted in majority of H. pylori-positive cases (OR = 1.43, 95% CI: 0.36, 5.65; P = 0.61). Gastric intestinal metaplasia was observed in 55.6% of H. pylori-positive patients and in 44.4% of negative individuals (OR = 0.74, 95% CI: 0.28, 1.94; P = 0.54). There was not a significant difference in the prevalence of HP in BE and control groups; 63.9% were positive for infection in BE cases and 61.7% of controls (OR = 1.10, 95% CI: 0.64, 1.90; P = 0.74). We found that neither presence of erosive esophagitis, length of BE nor dysplasia (45.5% of H. pylori-positive group, whereas 54.5%) was associated with the presence of the H. pylori infection (Table 1). In a predominantly Caucasian nation with a high prevalence of H. pylori gastritis, the presence of H. pylori was not inversely associated with the presence of Barrett's esophagus. These data challenge the mechanistic implications of this association.
Symptomatic and Radiographic Manifestations of Kidney Stone Recurrence and Their Prediction by Risk Factors: A Prospective Cohort Study

Journal of the American Society of Nephrology | June 7, 2019 | Volume: 30 | Issue: 7 | Pages: 1251-1260

10.1681/asn.2018121241 | PMID 31175141

Significance Statement Kidney stone recurrence can manifest with symptoms from stone passage or with asymptomatic changes in kidney stone burden revealed by radiography. In a multicenter, prospective cohort study, the authors demonstrate that substantially more asymptomatic and self-managed symptomatic kidney stone recurrence occur in stone formers than has been appreciated, as many studies consider only symptomatic recurrence that results in clinical care. Among first-time symptomatic stone formers, 54% had an asymptomatic kidney stone; half of those with such a stone passed it within 5 years (but only half who did so experienced symptoms). The findings also show that when a more comprehensive definition of recurrence that includes all symptomatic and radiological manifestations is used, risk factors better predict kidney stone recurrence, thus supporting a comprehensive assessment of recurrence in clinical trials. Background Meaningful interpretation of changes in radiographic kidney stone burden requires understanding how radiographic recurrence relates to symptomatic recurrence and how established risk factors predict these different manifestations of recurrence. Methods We recruited first-time symptomatic stone formers from the general community in Minnesota and Florida. Baseline and 5-year follow-up study visits included computed tomography scans, surveys, and medical record review. We noted symptomatic recurrence detected by clinical care (through chart review) or self-report, and radiographic recurrence of any new stone, stone growth, or stone passage (comparing baseline and follow-up scans). To assess the prediction of different manifestations of recurrence, we used the Recurrence of Kidney Stone (ROKS) score, which sums multiple baseline risk factors. Results Among 175 stone formers, 19% had symptomatic recurrence detected by clinical care and 25% detected by self-report; radiographic recurrence manifested as a new stone in 35%, stone growth in 24%, and stone passage in 27%. Among those with a baseline asymptomatic stone (54%), at 5 years, 51% had radiographic evidence of stone passage (accompanied by symptoms in only 52%). Imaging evidence of a new stone or stone passage more strongly associated with symptomatic recurrence detected by clinical care than by self-report. The ROKS score weakly predicted one manifestation—symptomatic recurrence resulting in clinical care ( c -statistic, 0.63; 95% confidence interval, 0.52 to 0.73)—but strongly predicted any manifestation of symptomatic or radiographic recurrence (5-year rate, 67%; c -statistic, 0.79; 95% confidence interval, 0.72 to 0.86). Conclusions Recurrence after the first stone episode is both more common and more predictable when all manifestations of recurrence (symptomatic and radiographic) are considered.