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Dive into the research topics where Velimir A. Luketic is active.

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Featured researches published by Velimir A. Luketic.


Hepatology | 2009

High‐dose ursodeoxycholic acid for the treatment of primary sclerosing cholangitis

Keith D. Lindor; Kris V. Kowdley; Velimir A. Luketic; M. Edwyn Harrison; Timothy M. McCashland; Alex S. Befeler; Denise M. Harnois; Roberta A. Jorgensen; Jan Petz; Jody Mooney; Carol Sargeant; Tamara Bernard; Debra King; Ellen Miceli; Jeff Schmoll; Tanya L. Hoskin; Prabin Thapa; Felicity Enders

Previous controlled trials are inconclusive regarding the efficacy of ursodeoxycholic acid (UDCA) for treating primary sclerosing cholangitis (PSC). One hundred fifty adult patients with PSC were enrolled in a long‐term, randomized, double‐blind controlled trial of high‐dose UDCA (28‐30 mg/kg/day) versus placebo. Liver biopsy and cholangiography were performed before randomization and after 5 years. The primary outcome measures were development of cirrhosis, varices, cholangiocarcinoma, liver transplantation, or death. The study was terminated after 6 years due to futility. At enrollment, the UDCA (n = 76) and placebo (n = 74) groups were similar with respect to sex, age, duration of disease, serum aspartate aminotransferase and alkaline phosphatase levels, liver histology, and Mayo risk score. During therapy, aspartate aminotransferase and alkaline phosphatase levels decreased more in the UDCA group than the placebo group (P < 0.01), but improvements in liver tests were not associated with decreased endpoints. By the end of the study, 30 patients in the UDCA group (39%) versus 19 patients in the placebo group (26%) had reached one of the pre‐established clinical endpoints. After adjustment for baseline stratification characteristics, the risk of a primary endpoint was 2.3 times greater for patients on UDCA than for those on placebo (P < 0.01) and 2.1 times greater for death, transplantation, or minimal listing criteria (P = 0.038). Serious adverse events were more common in the UDCA group than the placebo group (63% versus 37% [P < 0.01]). Conclusion: Long‐term, high‐dose UDCA therapy is associated with improvement in serum liver tests in PSC but does not improve survival and was associated with higher rates of serious adverse events. (HEPATOLOGY 2009.)


Transplantation | 1999

Right lobe living donor liver transplantation.

Amadeo Marcos; Robert A. Fisher; John M. Ham; Mitchell L. Shiffman; Arun J. Sanyal; Velimir A. Luketic; Richard K. Sterling; Marc P. Posner

1. Living donor liver transplantation (LDLT) is currently performed at about 30 centers in the United States. 2. Careful and critical evaluation of donor and recipient is required for optimal outcome. 3. Right lobe donation is preferred over left lobe donation in adult LDLT. 4. There has been 1 donor death (<0.3%) in the US experiences. Donor biliary complications occur in approximately 4% of the cases. 5. Recipient survival after adult LDLT in the United States is approximately 88%. Hepatic artery thrombosis occurs in 3% and biliary complications in 18%.


Hepatology | 2008

Nonalcoholic steatohepatitis is associated with altered hepatic MicroRNA expression

Onpan Cheung; Puneet Puri; Christoph Eicken; Melissa J. Contos; Faridoddin Mirshahi; James W. Maher; John M. Kellum; Hae-Ki Min; Velimir A. Luketic; Arun J. Sanyal

The expression of microRNA in nonalcoholic steatohepatitis (NASH) and their role in the genesis of NASH are not known. The aims of this study were to: (1) identify differentially expressed microRNAs in human NASH, (2) tabulate their potential targets, and (3) define the effect of a specific differentially expressed microRNA, miR‐122, on its targets and compare these effects with the pattern of expression of these targets in human NASH. The expression of 474 human microRNAs was compared in subjects with the metabolic syndrome and NASH versus controls with normal liver histology. Differentially expressed microRNAs were identified by the μParaflo microRNA microarray assay and validated using quantitative real‐time polymerase chain reaction (PCR). The effects of a specific differentially expressed miRNA (miR‐122) on its predicted targets were assessed by silencing and overexpressing miR‐122 in vitro. A total of 23 microRNAs were underexpressed or overexpressed. The predicted targets of these microRNAs are known to affect cell proliferation, protein translation, apoptosis, inflammation, oxidative stress, and metabolism. The miR‐122 level was significantly decreased in subjects with NASH (63% by real‐time PCR, P < 0.00001). Silencing miR‐122 led to an initial increase in mRNA levels of these targets (P < 0.05 for all) followed by a decrease by 48 hours. This was accompanied by an increase in protein levels of these targets (P < 0.05 for all). Overexpression of miR‐122 led to a significant decrease in protein levels of these targets. Conclusions: NASH is associated with altered hepatic microRNA expression. Underexpression of miR‐122 potentially contributes to altered lipid metabolism implicated in the pathogenesis of NASH. (HEPATOLOGY 2008;48:1810–1820.)


Clinical Gastroenterology and Hepatology | 2004

A pilot study of vitamin E versus vitamin E and pioglitazone for the treatment of nonalcoholic steatohepatitis

Arun J. Sanyal; Pouneh S. Mofrad; Melissa J. Contos; Carol Sargeant; Velimir A. Luketic; Richard K. Sterling; R. Todd Stravitz; Mitchell L. Shiffman; John N. Clore; A.S. Mills

BACKGROUND & AIMS Insulin resistance and oxidative stress contribute to the pathogenesis of nonalcoholic steatohepatitis (NASH). We conducted a pilot study for the following reasons: (1) to test the hypothesis that a combination of an antioxidant (vitamin E) and an insulin sensitizer (pioglitazone) would be superior to vitamin E alone for the treatment of NASH, and (2) to define the effects of these interventions on insulin-sensitive metabolic functions and correlate the effects with changes in liver histology. METHODS A randomized prospective trial was performed to compare the efficacy and safety of vitamin E alone (400 IU/day) vs. vitamin E (400 IU/day) and pioglitazone (30 mg/day) in nondiabetic, noncirrhotic subjects with NASH. Metabolic functions were assessed by a 2-step, hyperinsulinemic (10 and 40 mU/m2/min) euglycemic clamp. RESULTS A total of 10 patients were randomized to each arm. Two patients on combination therapy discontinued treatment; one because of pregnancy and the other because of hepatotoxicity. Treatment with vitamin E only produced a significant decrease in steatosis (mean grade, 2.2 vs. 1.4; P < .02). Compared with baseline, combination therapy produced a significant decrease in steatosis (mean, 2.3 vs. 1; P < .002), cytologic ballooning (1.3 vs. 0.2; P < .01), Mallorys hyaline (0.7 vs. 0.2; P < .04), and pericellular fibrosis (1.2 vs. 0.6; P < .03). Although vitamin E had no significant effects, combination therapy produced a significant increase in metabolic clearance of glucose and a decrease in fasting free fatty acid (FFA) and insulin. The decrease in fasting FFA and insulin independently predicted improvement in hepatic steatosis and cytologic ballooning. CONCLUSIONS A combination of vitamin E and pioglitazone produces a greater improvement in NASH histology. The improvement in steatosis and cytologic ballooning are related to treatment-associated decreases in fasting FFA and insulin levels.


Hepatology | 2006

SIMILARITIES AND DIFFERENCES IN OUTCOMES OF CIRRHOSIS DUE TO NONALCOHOLIC STEATOHEPATITIS AND HEPATITIS C

Arun J. Sanyal; Colin Banas; Carol Sargeant; Velimir A. Luketic; Richard K. Sterling; Richard T. Stravitz; Mitchell L. Shiffman; Douglas M. Heuman; Adrian Coterrell; Robert A. Fisher; Melissa J. Contos; A.S. Mills

The objective of this study was to prospectively define outcomes of cirrhosis due to nonalcoholic steatohepatitis (NASH) and compare them with those associated with hepatitis C virus (HCV) infection. We compared 152 patients with cirrhosis due to NASH with 150 matched patients with cirrhosis due to HCV. Over 10 years, 29/152 patients with cirrhosis due to NASH died compared with 44/150 patients with HCV (P < .04). This was mainly due to the lower mortality rate in patients with Child class A cirrhosis due to NASH versus HCV (3/74 vs. 15/75; P < .004). There were no significant across‐group differences in mortality in patients with Child class B or C cirrhosis. Sepsis was the most common cause of death in both groups; patients with NASH had a higher cardiac mortality (8/152 vs. 1/150; P < .03). Patients with Child class A cirrhosis due to NASH also had a significantly lower risk of decompensation, defined by a 2‐point increase in Child‐Turcotte‐Pugh score (P < .007). Cirrhosis due to NASH was associated with a lower rate of development of ascites (14/101 vs. 40/97 patients at risk; P < .006). NASH also had a significantly lower risk of development of hepatocellular carcinoma (10/149 vs. 25/147 patients at risk; P < .01). In conclusion, compensated cirrhosis due to NASH is associated with a lower mortality rate compared with that due to HCV. It is also associated with a lower rate of development of ascites, hyperbilirubinemia, and hepatocellular carcinoma. However, cardiovascular mortality is greater in patients with NASH. (HEPATOLOGY 2006.)


Transplantation | 2000

Liver regeneration and function in donor and recipient after right lobe adult to adult living donor liver transplantation

Amadeo Marcos; Robert A. Fisher; John M. Ham; Mitchell L. Shiffman; Arun J. Sanyal; Velimir A. Luketic; Richard K. Sterling; Ann S. Fulcher; Marc P. Posner

BACKGROUND Regeneration of the liver to a predetermined size after resection or transplantation is a well described phenomenon, but the time course over which these events occur has not been well defined. It is not clear how initial liver mass, reperfusion, immunosuppression, or steatosis influence this process. METHODS Liver regeneration was assessed prospectively by volumetric magnetic resonance imaging (MRI) in living right lobe liver donors and the recipients of these grafts. Imaging was performed at regular intervals through 60 days after resection/transplantation, and liver mass was determined. Liver function tests and synthetic function were monitored throughout the study period in donors and recipients of these grafts as well as recipients of cadaveric grafts. RESULTS MRI consistently overestimated liver mass by a mean of 45 g (+/-65) (range 10-123). Donor liver mass increased by 101%, 110%, 115%, and 144% at 7, 14, 30, and 60 days after resection, respectively. Recipient liver mass increased by 87,101, 119, and 99% at 7, 14, 30, and 60 days after transplantation, respectively. Steatosis did not influence the degree of regeneration or graft function, nor was there a functional difference between grafts of >1% graft to recipient body weight ratio or <1%. CONCLUSIONS MRI accurately determines right lobe mass. Most liver regeneration occurs in the 1st week after resection or transplantation, and the time course does not differ significantly in donors or recipients. The mass of the graft or remnant segment affects the duration of the regeneration process, with a smaller initial liver mass prolonging the course. Steatosis of <30% had no bearing on liver function or regeneration and, therefore, should not be an absolute criterion for exclusion of donors. A calculated graft to recipient body weight ratio of 0.8% is adequate for right lobe living donor liver transplantation.


Gastroenterology | 2003

Hepatitis B virus genotypes in the United States: results of a nationwide study

Chi—Jen Chu; Emmet B. Keeffe; Steven Han; Robert P. Perrillo; Albert D. Min; Consuelo Soldevila-Pico; William D. Carey; Robert S. Brown; Velimir A. Luketic; Norah A. Terrault; Anna S. Lok

BACKGROUND & AIMS Hepatitis B virus (HBV) genotypes may be related to severity of liver disease and treatment response. The aims of this nationwide study were to determine the prevalence of HBV genotypes in the United States and the association between HBV genotypes and patient demographics, mode of infection, and clinical status. METHODS A total of 694 consecutive chronic HBV-infected patients seen in 17 U.S. liver centers during a 1-year period were enrolled. Demographic, clinical, and laboratory data were collected. Sera were tested for HBV genotyping, precore, and core promoter variants by line-probe assays. RESULTS All 7 HBV genotypes (A-G) were found, with genotypes A and C the most common. The prevalence of HBV genotypes was different in different regions of the United States. A strong correlation was found between HBV genotypes and ethnicity. HBV genotype A was prevalent among white and black patients, whereas genotypes B and C were most common among Asian patients. The predominant genotype among patients born in the United States, Europe, the Far East, and Southeast Asia were A, D, C, and B, respectively. Genotypes A and C were associated with a higher prevalence of hepatitis B e antigen. Precore variant was detected in 27% of patients and core promoter variant in 44% of patients. CONCLUSIONS Our study suggests that the epidemiology of HBV infection in the United States may have changed over time as a result of immigration from countries with a high prevalence of HBV infection. HBV genotypes may account for the heterogeneity in disease manifestations among patients with chronic HBV infection.


Transplantation | 2000

Selection and Outcome of Living Donors for Adult to Adult Right Lobe Transplantation

Amadeo Marcos; Robert A. Fisher; John M. Ham; Ann T. Olzinski; Mitchell L. Shiffman; Arun J. Sanyal; Velimir A. Luketic; Richard K. Sterling; Mary E. Olbrisch; Marc P. Posner

BACKGROUND The shortage of cadaveric livers has sparked an interest in adult-to-adult living donor transplantation. Right lobe donor hepatectomy is frequently required to obtain a graft of adequate size for adult recipients. Careful donor selection is necessary to minimize complications and assure a functional graft. METHODS A four-step evaluation protocol was used for donor selection and satisfactory results of all tests in each step were required before proceeding to the next. Donors were selected based on a battery of laboratory studies chosen to exclude unrecognized infection, liver disease, metabolic disorders, and conditions representing undue surgical risk. Imaging studies included ultrasonography, angiography, magnetic resonance imaging, and intraoperative cholangiography and ultrasonography. The information obtained from liver biopsy was used to correct the estimated graft mass for the degree of steatosis. RESULTS From March 1998 to August 1999, 126 candidates were evaluated for living donation. A total of 35 underwent donor right lobectomy with no significant complications. Forty percent of all donors that came to surgery were genetically unrelated to the recipient. A total of 69% of those evaluated were excluded. ABO incompatibility was the primary reason for exclusion after the first step (71%) and the presence of steatosis yielding an inadequate estimated graft mass after the second step (20%). CONCLUSIONS Donor selection limits the application of living donor liver transplantation in the adult population. Unrelated individuals increase the size of the donor pool. Right lobe hepatectomy can be performed safely in healthy adult liver donors. Preoperative liver biopsy is an essential part of the evaluation protocol, particularly when the estimated graft mass is marginal.


Hepatology | 1995

A randomized, double-blind, placebo-controlled trial of ursodeoxycholic acid in primary biliary cirrhosis

Burton Combes; Robert L. Carithers; Willis C. Maddrey; D. Y. Lin; Mary F. McDonald; Donald E. Wheeler; Edwin H. Eigenbrodt; Santiago J. Munoz; Raphael Rubin; Guadalupe Garcia-Tsao; Gregory F. Bonner; Alexander B. West; James L. Boyer; Velimir A. Luketic; Mitchell L. Shiffman; A. Scott Mills; Marion Peters; Heather White; Rowen K. Zetterman; Stephen Rossi; Alan F. Hofmann; Rodney S. Markin

One hundred fifty-one patients with primary biliary cirrhosis (PBC) grouped into four strata based on entry serum bilirubin ( or +2 (strata 3 and 4). Histology was favorably affected by ursodiol in patients in strata 1 and 2 but not in strata 3 and 4. Ursodiol enrichment in fasting bile obtained at the conclusion of the trail was approximately 40% and comparable in all strata. Thus, differences in ursodiol enrichment of the bile acid pool do not explain better responses of laboratory tests and histology found in patients with less advanced PBC. Patients treated will ursodiol tended to develop a treatment failure less frequently that those who received placebo, particularly in strata 1 and 2 (ursodiol 42%, placebo 60%, P = .078). Development of severe symptoms (fatigue/pruritus) and doubling of serum bilirubin were reduced significantly in ursodiol-treated patients.(ABSTRACT TRUNCATED AT 250 WORDS)


Gastroenterology | 1999

A Randomized, Controlled Trial of Maintenance Interferon Therapy for Patients With Chronic Hepatitis C Virus and Persistent Viremia

Mitchell L. Shiffman; Charlotte M. Hofmann; Melissa J. Contos; Velimir A. Luketic; Arun J. Sanyal; Richard K. Sterling; Andrea Ferreira-Gonzalez; A. Scott Mills; Carlton Garret

BACKGROUND & AIMS : At least half of patients with chronic hepatitis C virus (HCV) fail to respond to interferon or interferon/ribavirin therapy. Histological improvement is observed in some nonresponders. We conducted a randomized, controlled trial to determine if maintenance interferon therapy could prevent histological progression in this subset of nonresponders. METHODS Fifty-three patients with chronic HCV were enrolled. All were HCV-RNA positive after 6 months of treatment with interferon alfa-2b but had a histological response. Twenty-seven of the patients were randomly assigned to continue interferon (3 MU 3 times weekly) for 24 months; 26 patients discontinued treatment and were observed prospectively. Alanine aminotransferase (ALT) level and HCV-RNA titer were monitored, and liver biopsy was repeated every 12 months. RESULTS Before interferon therapy, the 2 groups were well matched for all demographic factors, serum ALT (94.0 +/- 15.6), log HCV-RNA titer (5. 85 +/- 0.15 copies/mL), histology score (9.5 +/- 0.2), and percentage with cirrhosis (25%). After 6 months of treatment, significant reductions (P < 0.05) in serum ALT level (62.6 +/- 9.6), log HCV-RNA titer (4.79 +/- 0.13 copies/mL), and hepatic inflammation (4.0 +/- 0.2) were observed. These improvements were maintained in the patients randomized to continue interferon. Stopping treatment was associated with an increase in serum ALT, log HCV-RNA, and hepatic inflammation back to baseline. After 30 months of treatment, mean fibrosis score declined from 2.5 to 1.7 and 80% of patients had histological improvement (P < 0.03). Discontinuation of interferon was associated with an increase in mean fibrosis score from 2.2 to 2.4 and worsening of hepatic histology in 30% of patients (P < 0.01). CONCLUSIONS These data support the hypothesis that maintenance interferon may prevent histological progression of chronic HCV in patients who remain viremic.

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Arun J. Sanyal

Virginia Commonwealth University

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Richard K. Sterling

Virginia Commonwealth University

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R. Todd Stravitz

Virginia Commonwealth University

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Puneet Puri

Virginia Commonwealth University

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Michael Fuchs

Virginia Commonwealth University

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Melissa J. Contos

Virginia Commonwealth University

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Douglas M. Heuman

Virginia Commonwealth University

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Jasmohan S. Bajaj

Virginia Commonwealth University

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Richard T. Stravitz

Virginia Commonwealth University

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