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Dive into the research topics where Lorenzo Rossaro is active.

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Featured researches published by Lorenzo Rossaro.


The New England Journal of Medicine | 2014

Ledipasvir and Sofosbuvir for 8 or 12 Weeks for Chronic HCV without Cirrhosis

Kris V. Kowdley; Stuart C. Gordon; K. Rajender Reddy; Lorenzo Rossaro; David Bernstein; Eric Lawitz; Mitchell L. Shiffman; Eugene R. Schiff; Reem Ghalib; Michael E. Ryan; Vinod K. Rustgi; Mario Chojkier; Robert Herring; Adrian M. Di Bisceglie; Paul J. Pockros; G. Mani Subramanian; Di An; Evguenia Svarovskaia; Robert H. Hyland; Phillip S. Pang; William T. Symonds; John G. McHutchison; Andrew J. Muir; David Pound; Michael W. Fried

BACKGROUND High rates of sustained virologic response were observed among patients with hepatitis C virus (HCV) infection who received 12 weeks of treatment with the nucleotide polymerase inhibitor sofosbuvir combined with the NS5A inhibitor ledipasvir. This study examined 8 weeks of treatment with this regimen. METHODS In this phase 3, open-label study, we randomly assigned 647 previously untreated patients with HCV genotype 1 infection without cirrhosis to receive ledipasvir and sofosbuvir (ledipasvir-sofosbuvir) for 8 weeks, ledipasvir-sofosbuvir plus ribavirin for 8 weeks, or ledipasvir-sofosbuvir for 12 weeks. The primary end point was sustained virologic response at 12 weeks after the end of therapy. RESULTS The rate of sustained virologic response was 94% (95% confidence interval [CI], 90 to 97) with 8 weeks of ledipasvir-sofosbuvir, 93% (95% CI, 89 to 96) with 8 weeks of ledipasvir-sofosbuvir plus ribavirin, and 95% (95% CI, 92 to 98) with 12 weeks of ledipasvir-sofosbuvir. As compared with the rate of sustained virologic response in the group that received 8 weeks of ledipasvir-sofosbuvir, the rate in the 12-week group was 1 percentage point higher (97.5% CI, -4 to 6) and the rate in the group that received 8 weeks of ledipasvir-sofosbuvir with ribavirin was 1 percentage point lower (95% CI, -6 to 4); these results indicated noninferiority of the 8-week ledipasvir-sofosbuvir regimen, on the basis of a noninferiority margin of 12 percentage points. Adverse events were more common in the group that received ribavirin than in the other two groups. No patient who received 8 weeks of only ledipasvir-sofosbuvir discontinued treatment owing to adverse events. CONCLUSIONS Ledipasvir-sofosbuvir for 8 weeks was associated with a high rate of sustained virologic response among previously untreated patients with HCV genotype 1 infection without cirrhosis. No additional benefit was associated with the inclusion of ribavirin in the regimen or with extension of the duration of treatment to 12 weeks. (Funded by Gilead Sciences; ION-3 ClinicalTrials.gov number, NCT01851330.).


The Lancet | 2010

Efficacy of boceprevir, an NS3 protease inhibitor, in combination with peginterferon alfa-2b and ribavirin in treatment-naive patients with genotype 1 hepatitis C infection (SPRINT-1): an open-label, randomised, multicentre phase 2 trial.

Paul Y. Kwo; Eric Lawitz; Jonathan McCone; Eugene R. Schiff; John M. Vierling; David Pound; Mitchell Davis; Joseph S. Galati; Stuart C. Gordon; Natarajan Ravendhran; Lorenzo Rossaro; Frank H Anderson; Ira M. Jacobson; Raymond A. Rubin; Kenneth Koury; Lisa D. Pedicone; Clifford A. Brass; Eirum Chaudhri; Janice K. Albrecht

BACKGROUND Peginterferon plus ribavirin achieves sustained virological response (SVR) in fewer than half of patients with genotype 1 chronic hepatitis C virus infection treated for 48 weeks. We tested the efficacy of boceprevir, an NS3 hepatitis C virus oral protease inhibitor, when added to peginterferon alfa-2b and ribavirin. METHODS In part 1 of this trial, undertaken in 67 sites in the USA, Canada, and Europe, 520 treatment-naive patients with genotype 1 hepatitis C virus infection were randomly assigned to receive peginterferon alfa-2b 1.5 mug/kg plus ribavirin 800-1400 mg daily for 48 weeks (PR48; n=104); peginterferon alfa-2b and ribavirin daily for 4 weeks, followed by peginterferon alfa-2b, ribavirin, and boceprevir 800 mg three times a day for 24 weeks (PR4/PRB24; n=103) or 44 weeks (PR4/PRB44; n=103); or peginterferon alfa-2b, ribavirin, and boceprevir three times a day for 28 weeks (PRB28; n=107) or 48 weeks (PRB48; n=103). In part 2, 75 patients were randomly assigned to receive either PRB48 (n=16) or low-dose ribavirin (400-1000 mg) plus peginterferon alfa-2b and boceprevir three times a day for 48 weeks (low-dose PRB48; n=59). Randomisation was by computer-generated code, and study personnel and patients were not masked to group assignment. The primary endpoint was SVR 24 weeks after treatment. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00423670. FINDINGS Patients in all four boceprevir groups had higher rates of SVR than did the control group (58/107 [54%, 95% CI 44-64], p=0.013 for PRB28; 58/103 [56%, 44-66], p=0.005 for PR4/PRB24; 69/103 [67%, 57-76], p<0.0001 for PRB48; and 77/103 [75%, 65-83], p<0.0001 for PR4/PRB44; vs 39/104 [38%, 28-48] for PR48 control). Low-dose ribavirin was associated with a high rate of viral breakthrough (16/59 [27%]), and a rate of relapse (six of 27 [22%]) similar to control (12/51 [24%]). Boceprevir-based groups had higher rates of anaemia (227/416 [55%] vs 35/104 [34%]) and dysgeusia (111/416 [27%] vs nine of 104 [9%]) than did the control group. INTERPRETATION In patients with untreated genotype 1 chronic hepatitis C infection, the addition of the direct-acting antiviral agent boceprevir to standard treatment with peginterferon and ribavirin after a 4-week lead-in seems to have the potential to double the sustained response rate compared with that recorded with standard treatment alone. FUNDING Merck.


Gastroenterology | 2008

A Randomized, Prospective, Double-Blind, Placebo-Controlled Trial of Terlipressin for Type 1 Hepatorenal Syndrome

Arun J. Sanyal; Thomas D. Boyer; Guadalupe Garcia-Tsao; Frederick Regenstein; Lorenzo Rossaro; Beate Appenrodt; Andres T. Blei; Veit Gülberg; Samuel Sigal; Peter Teuber

BACKGROUND & AIMS Hepatorenal syndrome (HRS) type 1 is a progressive functional renal failure in subjects with advanced liver disease. The aim of this study was to evaluate the efficacy and safety of terlipressin, a systemic arterial vasoconstrictor, for cirrhosis type 1 HRS. METHODS A prospective, randomized, double-blind, placebo-controlled clinical trial of terlipressin was performed. Subjects with type 1 HRS were randomized to terlipressin (1 mg intravenously every 6 hours) or placebo plus albumin in both groups. The dose was doubled on day 4 if the serum creatinine (SCr) level did not decrease by 30% of baseline. Treatment was continued to day 14 unless treatment success, death, dialysis, or transplantation occurred. Treatment success was defined by a decrease in SCr level to </=1.5 mg/dL for at least 48 hours by day 14 without dialysis, death, or relapse of HRS type 1. RESULTS Fifty-six subjects were randomized to each arm. Treatment success with terlipressin was double that with placebo (25% vs 12.5%, P = .093). SCr level improved from baseline to day 14 on terlipressin (-0.7 mg/dL) as compared with placebo (0 mg/dL), P < .009. Terlipressin was superior to placebo for HRS reversal (34% vs 13%, P = .008), defined by decrease in SCr level </=1.5 mg/dL. Overall and transplantation-free survival was similar between study groups; HRS reversal significantly improved survival at day 180. One nonfatal myocardial infarction occurred with terlipressin, but the total adverse event rate was similar to placebo. CONCLUSIONS Terlipressin is an effective treatment to improve renal function in HRS type 1.


Gastroenterology | 2009

Intravenous N-acetylcysteine improves transplant-free survival in early stage non-acetaminophen acute liver failure.

William M. Lee; Linda S. Hynan; Lorenzo Rossaro; Robert J. Fontana; R. Todd Stravitz; Anne M. Larson; Timothy J. Davern; Natalie Murray; Timothy M. McCashland; Joan S. Reisch; Patricia R. Robuck

BACKGROUND & AIMS N-acetylcysteine (NAC), an antidote for acetaminophen poisoning, might benefit patients with non-acetaminophen-related acute liver failure. METHODS In a prospective, double-blind trial, acute liver failure patients without clinical or historical evidence of acetaminophen overdose were stratified by site and coma grade and assigned randomly to groups that were given NAC or placebo (dextrose) infusion for 72 hours. The primary outcome was overall survival at 3 weeks. Secondary outcomes included transplant-free survival and rate of transplantation. RESULTS A total of 173 patients received NAC (n = 81) or placebo (n = 92). Overall survival at 3 weeks was 70% for patients given NAC and 66% for patients given placebo (1-sided P = .283). Transplant-free survival was significantly better for NAC patients (40%) than for those given placebo (27%; 1-sided P = .043). The benefits of transplant-free survival were confined to the 114 patients with coma grades I-II who received NAC (52% compared with 30% for placebo; 1-sided P = .010); transplant-free survival for the 59 patients with coma grades III-IV was 9% in those given NAC and 22% in those given placebo (1-sided P = .912). The transplantation rate was lower in the NAC group but was not significantly different between groups (32% vs 45%; P = .093). Intravenous NAC generally was well tolerated; only nausea and vomiting occurred significantly more frequently in the NAC group (14% vs 4%; P = .031). CONCLUSIONS Intravenous NAC improves transplant-free survival in patients with early stage non-acetaminophen-related acute liver failure. Patients with advanced coma grades do not benefit from NAC and typically require emergency liver transplantation.


Critical Care Medicine | 2007

Intensive care of patients with acute liver failure: Recommendations of the U.S. Acute Liver Failure Study Group

R. Todd Stravitz; Andreas H. Kramer; Timothy J. Davern; A. Obaid S Shaikh; Stephen H. Caldwell; Ravindra L. Mehta; Andres T. Blei; Robert J. Fontana; Brendan M. McGuire; Lorenzo Rossaro; Alastair D. Smith; William M. Lee

Objective:To provide a uniform platform from which to study acute liver failure, the U.S. Acute Liver Failure Study Group has sought to standardize the management of patients with acute liver failure within participating centers. Methods:In areas where consensus could not be reached because of divergent practices and a paucity of studies in acute liver failure patients, additional information was gleaned from the intensive care literature and literature on the management of intracranial hypertension in non-acute liver failure patients. Experts in diverse fields were included in the development of a standard study-wide management protocol. Measurements and Main Results:Intracranial pressure monitoring is recommended in patients with advanced hepatic encephalopathy who are awaiting orthotopic liver transplantation. At an intracranial pressure of ≥25 mm Hg, osmotic therapy should be instituted with intravenous mannitol boluses. Patients with acute liver failure should be maintained in a mildly hyperosmotic state to minimize cerebral edema. Accordingly, serum sodium should be maintained at least within high normal limits, but hypertonic saline administered to 145–155 mmol/L may be considered in patients with intracranial hypertension refractory to mannitol. Data are insufficient to recommend further therapy in patients who fail osmotherapy, although the induction of moderate hypothermia appears to be promising as a bridge to orthotopic liver transplantation. Empirical broad-spectrum antibiotics should be administered to any patient with acute liver failure who develops signs of the systemic inflammatory response syndrome, or unexplained progression to higher grades of encephalopathy. Other recommendations encompassing specific hematologic, renal, pulmonary, and endocrine complications of acute liver failure patients are provided, including their management during and after orthotopic liver transplantation. Conclusions:The present consensus details the intensive care management of patients with acute liver failure. Such guidelines may be useful not only for the management of individual patients with acute liver failure, but also to improve the uniformity of practices across academic centers for the purpose of collaborative studies.


The New England Journal of Medicine | 2009

Peginterferon Alfa-2a and Ribavirin in Latino and Non-Latino Whites with Hepatitis C

Maribel Rodriguez-Torres; Lennox J. Jeffers; Muhammad Y. Sheikh; Lorenzo Rossaro; Victor Ankoma-Sey; Fayez M. Hamzeh; Paul Martin

BACKGROUND Race has been shown to be a factor in the response to therapy for hepatitis C virus (HCV) infection, and limited data suggest that ethnic group may be as well; however, Latinos and other ethnic subpopulations have been underrepresented in clinical trials. We evaluated the effect of Latino ethnic background on the response to treatment with peginterferon alfa-2a and ribavirin in patients infected with HCV genotype 1 who had not been treated previously. METHODS In a multicenter, open-label, nonrandomized, prospective study, 269 Latino and 300 non-Latino whites with HCV infection received peginterferon alfa-2a, at a dose of 180 microg per week, and ribavirin, at a dose of 1000 or 1200 mg per day, for 48 weeks, and were followed through 72 weeks. The primary end point was a sustained virologic response. We enrolled Latinos whose parents and grandparents spoke Spanish as their primary language; nonwhite Latinos were excluded. RESULTS Baseline characteristics were similar in the Latino and non-Latino groups, although higher proportions of Latino patients were 40 years of age or younger, had a body-mass index (BMI, the weight in kilograms divided by the square of the height in meters) of more than 27 or more than 30, and had cirrhosis. The rate of sustained virologic response was higher among non-Latino whites than among Latinos (49% vs. 34%, P<0.001). The absence of HCV RNA in serum was more frequent in non-Latino whites at week 4 (P=0.045) and throughout the treatment period (P<0.001 for all other comparisons). Latino or non-Latino background was an independent predictor of the rate of sustained virologic response in an analysis adjusted for baseline differences in BMI, cirrhosis, and other characteristics. Adherence to treatment did not differ significantly between the two groups. The numbers of patients with adverse events and dose modifications were similar in the two groups, but fewer Latino patients discontinued therapy because of adverse events. CONCLUSIONS Treatment with peginterferon alfa-2a and ribavirin for 48 weeks resulted in rates of sustained virologic response among patients infected with HCV genotype 1 that were lower among Latino whites than among non-Latino whites. Strategies to improve the sustained virologic response in Latinos are needed. (ClinicalTrials.gov number, NCT00107653.)


Hepatology | 2008

Screening for Wilson Disease in Acute Liver Failure: A Comparison of Currently Available Diagnostic Tests

Jessica D. Korman; Irene Volenberg; Jody Balko; Joe Webster; Frank V. Schiødt; Robert H. Squires; Robert J. Fontana; William M. Lee; Michael Schilsky; Julie Polson; Carla Pezzia; Ezmina Lalani; Linda S. Hynan; Joan S. Reisch; Anne M. Larson; Hao Do; Jeffrey S. Crippin; Laura Gerstle; Timothy J. Davern; Katherine Partovi; Sukru Emre; Timothy M. McCashland; Tamara Bernard; J. Eileen Hay; Cindy Groettum; Natalie Murray; Sonnya Coultrup; A. Obaid Shakil; Diane Morton; Andres T. Blei

Acute liver failure (ALF) due to Wilson disease (WD) is invariably fatal without emergency liver transplantation. Therefore, rapid diagnosis of WD should aid prompt transplant listing. To identify the best method for diagnosis of ALF due to WD (ALF‐WD), data and serum were collected from 140 ALF patients (16 with WD), 29 with other chronic liver diseases and 17 with treated chronic WD. Ceruloplasmin (Cp) was measured by both oxidase activity and nephelometry and serum copper levels by atomic absorption spectroscopy. In patients with ALF, a serum Cp <20 mg/dL by the oxidase method provided a diagnostic sensitivity of 21% and specificity of 84% while, by nephelometry, a sensitivity of 56% and specificity of 63%. Serum copper levels exceeded 200 μg/dL in all ALF‐WD patients measured (13/16), but were also elevated in non‐WD ALF. An alkaline phosphatase (AP) to total bilirubin (TB) ratio <4 yielded a sensitivity of 94%, specificity of 96%, and a likelihood ratio of 23 for diagnosing fulminant WD. In addition, an AST:ALT ratio >2.2 yielded a sensitivity of 94%, a specificity of 86%, and a likelihood ratio of 7 for diagnosing fulminant WD. Combining the tests provided a diagnostic sensitivity and specificity of 100%. Conclusion: Conventional WD testing utilizing serum ceruloplasmin and/or serum copper levels are less sensitive and specific in identifying patients with ALF‐WD than other available tests. More readily available laboratory tests including alkaline phosphatase, bilirubin and serum aminotransferases by contrast provides the most rapid and accurate method for diagnosis of ALF due to WD. (HEPATOLOGY 2008.)


Hepatology | 2010

Serum cholesterol and statin use predict virological response to peginterferon and ribavirin therapy

Stephen A. Harrison; Lorenzo Rossaro; Ke-Qin Hu; Keyur Patel; Hans L. Tillmann; Sandeep Dhaliwal; Dawn M. Torres; Kenneth Koury; Venkata Sasikiran Goteti; Stephanie Noviello; Clifford A. Brass; Janice K. Albrecht; John G. McHutchison; Mark S. Sulkowski

Elevated low‐density lipoprotein (LDL) levels and statin use have been associated with higher sustained virological response (SVR) rates in patients receiving chronic hepatitis C therapy. However, these relationships have not been well characterized in randomized controlled trials. Furthermore, little is known about the relationship between high‐density lipoprotein (HDL) and virological response. To determine whether baseline LDL or HDL levels and statin use affect SVR rates, we retrospectively evaluated the IDEAL (Individualized Dosing Efficacy Versus Flat Dosing to Assess Optimal Pegylated Interferon Therapy) trial, in which 3070 treatment‐naive, hepatitis C virus (HCV) genotype 1–infected patients were treated for up to 48 weeks in one of the following arms: (1) peginterferon (PEG‐IFN) alfa‐2b at 1.5 μg/kg/week with ribavirin (RBV) at 800 to 1400 mg/day, (2) PEG‐IFN alfa‐2b at 1.0 μg/kg/week with RBV at 800 to 1400 mg/day, or (3) PEG‐IFN alfa‐2a at 180 μg/week with RBV at 1000 to 1200 mg/day. Virological responses were assessed by pretreatment statin use and baseline elevated LDL levels (≥130 mg/dL) or low HDL levels (<40 mg/dL for men and <50 mg/dL for women). In 1464 patients with baseline elevated LDL levels or low HDL levels, the SVR rate was significantly higher than that in patients with normal levels (44.9% versus 34.0%, P < 0.001). In 66 patients receiving a statin pretreatment, the SVR rate was higher than the rate of those not receiving it (53.0% versus 39.3%, P = 0.02). In a multivariate logistic regression analysis using the stepwise selection method with baseline characteristics, a high LDL level [odds ratio (OR) = 1.6, 95% confidence interval (CI) = 1.4‐1.8, P < 0.001], a low HDL level (OR = 0.5, 95% CI = 0.3‐0.8, P = 0.004), and statin use (OR = 2.0, 95% CI = 1.1‐3.7, P = 0.02) were independently associated with SVR. Conclusion: Baseline elevated LDL levels or low HDL levels and preemptive statin usage were associated with higher SVR rates. Prospective studies may be considered to explore the biological impact of these factors on HCV RNA replication and treatment response. (HEPATOLOGY 2010;)


Hepatology | 2007

Antimitochondrial antibodies in acute liver failure: Implications for primary biliary cirrhosis

Patrick S.C. Leung; Lorenzo Rossaro; Paul A. Davis; Ogyi Park; Atsushi Tanaka; Kentaro Kikuchi; Hiroshi Miyakawa; Gary L. Norman; William M. Lee; M. Eric Gershwin; W.M. Lee; Julie Polson; Carla Pezzia; Anne M. Larson; Timothy J. Davern; Paul Martin; Timothy M. McCashland; J. Eileen Hay; Natalie Murray; A. Obaid Shakil; Andres T. Blei; Atif Zaman; Steven Han; Robert J. Fontana; Brendan M. McGuire; Raymond T. Chung; Alastair D. Smith; Michael Schilsky; Adrian Reuben; Santiago Munoz

In our previous work, including analysis of more than 10,000 sera from control patients and patients with a variety of liver diseases, we have demonstrated that with the use of recombinant autoantigens, antimitochondrial autoantibodies (AMAs) are only found in primary biliary cirrhosis (PBC) and that a positive AMA is virtually pathognomonic of either PBC or future development of PBC. Although the mechanisms leading to the generation of AMA are enigmatic, we have postulated that xenobiotic‐induced and/or oxidative modification of mitochondrial autoantigens is a critical step leading to loss of tolerance. This thesis suggests that a severe liver oxidant injury would lead to AMA production. We analyzed 217 serum samples from 69 patients with acute liver failure (ALF) collected up to 24 months post‐ALF, compared with controls, for titer and reactivity with the E2 subunits of pyruvate dehydrogenase, branched chain 2‐oxo‐acid dehydrogenase, and 2‐oxo‐glutarate dehydrogenase. AMAs were detected in 28/69 (40.6%) ALF patients with reactivity found against all of the major mitochondrial autoantigens. In addition, and as further controls, sera were analyzed for autoantibodies to gp210, Sp100, centromere, chromatin, soluble liver antigen, tissue transglutaminase, and deaminated gliadin peptides; the most frequently detected nonmitochondrial autoantibody was against tissue transglutaminase (57.1% of ALF patients). Conclusion: The strikingly high frequency of AMAs in ALF supports the thesis that oxidative stress‐induced liver damage may lead to AMA induction. The rapid disappearance of AMAs in these patients provides further support for the contention that PBC pathogenesis requires additional factors, including genetic susceptibility. (HEPATOLOGY 2007.)


The American Journal of Gastroenterology | 2005

Erythropoietic Response to Anemia in Chronic Hepatitis C Patients Receiving Combination Pegylated Interferon/Ribavirin

Vijayan Balan; David A. Schwartz; George Y. Wu; Andrew J. Muir; Reem Ghalib; John Jackson; Emmet B. Keeffe; Lorenzo Rossaro; Alfreda Burnett; Betty L. Goon; Peter J. Bowers; Gerhard Leitz

OBJECTIVES:In hepatitis C virus (HCV)-infected patients receiving pegylated interferon (PEG-IFN)/ribavirin (RBV) combination therapy, anemia is a well-known side effect. The purpose of this study was to describe the time course and extent of hemoglobin (Hb) changes and the erythropoietic response to PEG-IFN/RBV-induced anemia.METHODS:In this multicenter, observational, 8-wk study, laboratory parameters were measured weekly for 8 wk or until early withdrawal. Primary endpoints included changes in Hb and serum erythropoietin (sEPO) from baseline to week 8; other measures were changes in reticulocytes and RBV dose. The predictive value of baseline factors for maximum Hb decline was assessed.RESULTS:In the 97 evaluable patients, mean Hb decreased from 14.4 ± 1.4 g/dl (baseline) to 11.9 ± 1.3 g/dl (week 8). Twenty-one percent of patients withdrew before week 8. The estimated erythropoietic response was lower than that seen in two historic control populations of iron deficiency anemia patients. Mean RBV dose decreased from 986 ± 190 mg/day (baseline) to 913 ± 228 mg/day (week 8). Fifty-seven out of 77 (74%) patients who completed the study maintained their initial prescribed RBV dose. Patients maintained on the initial dose of RBV who had a higher baseline Hb and viral load showed a trend toward larger Hb declines. Platelets and white blood cells (WBCs) also declined during the study.CONCLUSIONS:HCV-infected patients receiving PEG-IFN/RBV therapy have reductions in Hb, platelets, and WBCs, possibly due to bone marrow suppression. They also have diminished endogenous sEPO production for their degree of anemia.

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William M. Lee

University of Texas Southwestern Medical Center

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Anne M. Larson

University of Washington

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Natalie Murray

Baylor University Medical Center

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Timothy M. McCashland

University of Nebraska Medical Center

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Brendan M. McGuire

University of Alabama at Birmingham

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