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Dive into the research topics where Karen F. Murray is active.

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Featured researches published by Karen F. Murray.


Inflammatory Bowel Diseases | 2005

A randomized, double-blind trial of lactobacillus GG versus placebo in addition to standard maintenance therapy for children with Crohn's disease

Athos Bousvaros; Stefano Guandalini; Robert N. Baldassano; Christine Botelho; Jonathan Evans; George D. Ferry; Barry R. Goldin; Lori Hartigan; Subra Kugathasan; Joseph Levy; Karen F. Murray; Maria Oliva-Hemker; Joel R. Rosh; Vasundhara Tolia; Anna Zholudev; Jon A. Vanderhoof; Patricia L. Hibberd

&NA; Probiotics are widely used by patients with Crohns disease (CD) in an attempt to improve their health, but few controlled studies have been done to evaluate the efficacy of these therapies. We conducted a randomized, placebo‐controlled trial of the probiotic Lactobacillus rhamnosus strain GG (LGG) to see if the addition of LGG to standard therapy prolonged remission in children with CD. Concomitant medications allowed in the study included aminosalicylates, 6‐mercaptopurine, azathioprine, and low‐dose alternate day corticosteroids. Seventy‐five children (age range, 5‐21 yr) with CD in remission were randomized to either LGG (n = 39) or placebo (n = 36) and followed for up to 2 years. The median time to relapse was 9.8 months in the LGG group and 11.0 months in the placebo group (P = 0.24); 31% (12/39) of patients in the LGG group developed a relapse compared with 6/36 (17%) of the placebo group (P = 0.18). The LGG was well tolerated, with a side effect profile comparable with placebo. This study suggests that LGG does not prolong time to relapse in children with CD when given as an adjunct to standard therapy.


Biology of Blood and Marrow Transplantation | 2010

Defibrotide for the treatment of severe hepatic veno-occlusive disease and multiorgan failure after stem cell transplantation: a multicenter, randomized, dose-finding trial.

Paul G. Richardson; Robert J. Soiffer; Joseph H. Antin; Hajime Uno; Zhezhen Jin; Joanne Kurtzberg; Paul L. Martin; Gideon Steinbach; Karen F. Murray; Georgia B. Vogelsang; Allen R. Chen; Amrita Krishnan; Nancy A. Kernan; David Avigan; Thomas R. Spitzer; Howard M. Shulman; Donald N. Di Salvo; Carolyn Revta; Diane Warren; Parisa Momtaz; Gary Bradwin; L. J. Wei; Massimo Iacobelli; George B. McDonald; Eva C. Guinan

Therapeutic options for severe hepatic veno-occlusive disease (VOD) are limited and outcomes are dismal, but early phase I/II studies have suggested promising activity and acceptable toxicity using the novel polydisperse oligonucleotide defibrotide. This randomized phase II dose-finding trial determined the efficacy of defibrotide in patients with severe VOD following hematopoietic stem cell transplantation (HSCT) and identified an appropriate dose for future trials. Adult and pediatric patients received either lower-dose (arm A: 25 mg/kg/day; n = 75) or higher-dose (arm B: 40 mg/kg/day; n = 74) i.v. defibrotide administered in divided doses every 6 hours for > or =14 days or until complete response, VOD progression, or any unacceptable toxicity occurred. Overall complete response and day +100 post-HSCT survival rates were 46% and 42%, respectively, with no significant difference between treatment arms. The incidence of treatment-related adverse events was low (8% overall; 7% in arm A, 10% in arm B); there was no significant difference in the overall rate of adverse events between treatment arms. Early stabilization or decreased bilirubin was associated with better response and day +100 survival, and decreased plasminogen activator inhibitor type 1 (PAI-1) during treatment was associated with better outcome; changes were similar in both treatment arms. Defibrotide 25 or 40 mg/kg/day also appears effective in treating severe VOD following HSCT. In the absence of any differences in activity, toxicity or changes in PAI-1 level, defibrotide 25 mg/kg/day was selected for ongoing phase III trials in VOD.


Hepatology | 2005

Interferon alfa‐2b in combination with ribavirin for the treatment of chronic hepatitis C in children: Efficacy, safety, and pharmacokinetics

Regino P. Gonzalez-Peralta; Deirdre Kelly; Barbara Haber; Jean P. Molleston; Karen F. Murray; Maureen M. Jonas; Mark Shelton; Giorgina Mieli-Vergani; Yoav Lurie; Steven R. Martin; Thomas Lang; Andrew Baczkowski; Michael Geffner; Samir Gupta; Mark Laughlin

Chronic hepatitis C virus (HCV) infection is usually asymptomatic in children, but significant liver disease may occur. We evaluated the efficacy, safety, and pharmacokinetics of interferon alfa‐2b and ribavirin in children with chronic HCV. We determined the optimal ribavirin dose in an initial cohort of a phase 1 study and then subsequently used it, in combination with interferon alfa‐2b, in a second cohort of this study and a phase 3 trial. The primary efficacy endpoint in all studies was sustained virological response, defined by undetectable serum HCV RNA 24 weeks after completion of therapy. All efficacy and safety analyses were performed on the intent‐to‐treat population. Children receiving interferon alfa‐2b plus ribavirin 15 mg/kg/d in the phase 1 study had the maximum reduction in serum HCV RNA at treatment weeks 4 and 12 with an acceptable safety profile. This ribavirin dose was selected as optimal and used in all subsequent studies. In all, 46% (54/118) of optimally treated children achieved sustained virological response. Sustained virological response was significantly higher in children with HCV genotype 2/3 (84%) than in those with HCV genotype 1 (36%). Adverse events led to dose modification in 37 (31%) and discontinuation in 8 (7%). Multiple‐dose interferon alfa‐2b and ribavirin peak and trough concentrations and area‐under‐the‐curve were similar between children and adults. In conclusion, interferon alfa‐2b in combination with ribavirin is effective and safe in children with chronic hepatitis C virus. (HEPATOLOGY 2005;42:1010–1018.)


Journal of Pediatric Gastroenterology and Nutrition | 2002

An analysis of published trials of interferon monotherapy in children with chronic hepatitis C.

Karen R. Jacobson; Karen F. Murray; Aglaia Zellos; Kathleen B. Schwarz

Background Although no therapeutic regimen has received Food and Drug Administration approval for treating children with chronic hepatitis C viral infection (CHC), there have been a number of pediatric interferon-&agr; (IFN-&agr;) trials. The purpose of this study was to perform a critical review of these trials to determine 1) end-of-treatment (ETR) and sustained-response (SR) rates, 2) predictors of response to therapy, and 3) safety of and tolerance to IFN-&agr; in children with CHC. Methods Relevant studies in the English-language medical literature and abstracts (January 1990 through November 2000) were identified by searching for manuscripts that contained the key words “children,” “hepatitis C,” and “interferon.” Trials were considered eligible for inclusion in this analysis if criteria for treatment included positive serum polymerase chain reaction for hepatitis C virus RNA (HCV PCR). Results Twenty published manuscripts of the use of IFN-&agr; in children with CHC were found, of which 12 met our inclusion criteria. Twenty-two abstracts, of which seven met our inclusion criteria, were identified. In the 19 included trials, 366 treated and 105 untreated children were observed; five countries were represented. Average ETR was 54% (0%–91%) and average SR was 36% (0%–73%). The SR in children with genotype 1 was 27% versus 70% for nongenotype 1 (P = 0.001). Five of 105 (5%) untreated controls exhibited spontaneous viral clearance. Conclusions To date, there is no published large-scale, multicenter, prospective, placebo-controlled randomized trial of the use of IFN-&agr; in children with CHC. The data in this review suggest that IFN-&agr; in children with CHC does have reasonable efficacy and safety. This review highlights the need for a more systematic design of future pediatric CHC trials. Ideally, such trials would be large scale, prospective, and controlled, and would include HCV genotype and viral load, histology, quality of life measures, and systematic recording of adverse events and of effects of therapy on growth and development.


Gastroenterology | 2011

The combination of ribavirin and peginterferon is superior to peginterferon and placebo for children and adolescents with chronic hepatitis C

Kathleen B. Schwarz; Regino P. Gonzalez-Peralta; Karen F. Murray; Jean P. Molleston; Barbara Haber; Maureen M. Jonas; Philip J. Rosenthal; Parvathi Mohan; William F. Balistreri; Michael R. Narkewicz; Lesley J. Smith; Steven J. Lobritto; Stephen J. Rossi; Alexandra Valsamakis; Zachary D. Goodman; Patricia R. Robuck; Bruce A. Barton

BACKGROUND & AIMS Although randomized trials of adults infected with hepatitis C virus (HCV) have shown that ribavirin increases the efficacy of pegylated interferon (PEG), such trials have not been performed in children. We conducted a randomized controlled trial of PEG and ribavirin, compared with PEG and placebo, in children 5 to 17 years old with chronic hepatitis C. METHODS HCV RNA-positive children from 11 university medical centers were randomly assigned to receive either PEG alfa-2a (PEG-2a; 180 μg/1.73 m(2) body surface area, subcutaneously each week; n = 55) and ribavirin (15 mg/kg orally in 2 doses daily) or PEG-2a and placebo (n = 59) for 48 weeks. The primary end point was sustained virologic response (SVR; lack of detectable HCV RNA at least 24 weeks after stopping therapy). RESULTS SVR was achieved in 53% of children treated with PEG-2a and ribavirin, compared with 21% of children who received PEG-2a and placebo (P < .001). Early virologic response (HCV RNA reduction >2 log(10) IU at 12 weeks) had a negative predictive value of only 0.89 in children with genotype 1, indicating that these children might benefit from 24 weeks of therapy before stopping treatment. Side effects, especially neutropenia, led to dose modification in 40% of children. Eighty-two percent of the PEG/ribavirin and 86% of the PEG/placebo group were in compliance with the year 2 follow-up visit; the durability of virologic response was 100% in both groups. CONCLUSIONS The combination of PEG and ribavirin is superior to PEG and placebo as therapy for chronic hepatitis C in children and adolescents.


Journal of Pediatric Gastroenterology and Nutrition | 2008

Drug-related hepatotoxicity and acute liver failure.

Karen F. Murray; Nedim Hadzic; Stefan Wirth; Mikelle D. Bassett; Deirdre Kelly

Drug-induced acute liver failure (ALF) accounts for approximately 20% of ALF in children and a higher percentage of ALF in adults. Although most patients experience milder drug hepatotoxic reactions such as hepatitis, cholestasis, or asymptomatic enzyme elevation, it is important to recognize the potential for progression to ALF. The most common cause of drug-induced ALF in children is acetaminophen (15% of all ALF in children in the United Kingdom and the United States), whereas other drugs such as antituberculous and antiepileptic therapy account for 5%. The pathogenesis of liver injury includes direct hepatotoxicity and idiosyncratic reactions for most drugs, although for others the mechanism of injury is assumed on the basis of clinical presentation and hepatic histological findings. We review the adult and pediatric literature of drug-induced hepatotoxicity and ALF, with special attention to commonly used or offending medications, mechanism of the toxicity, clinical presentation, diagnosis, treatment, and prognosis. Although most of the available information is based on experience in adult patients, we have included that which is applicable to children, or we have cited pediatric examples. Enhanced awareness of the potential hepatotoxicity of commonly prescribed medications may minimize the frequency of serious hepatotoxicity and ALF in pediatric patients.


The Journal of Pediatrics | 1993

Dietary protein intolerance in infants with transient methemoglobinemia and diarrhea

Karen F. Murray; Dennis L. Christie

Of 17 infants requiring hospitalization for primary soy or cow milk protein intolerance, six infants (35%) had transient methemoglobinemia. Reexposure to the offending protein caused diarrhea, metabolic acidosis, and transient methemoglobinemia in all patients. These six patients represented 65% of the total hospitalizations resulting from methemoglobinemia of any cause.


Contemporary Clinical Trials | 2010

Treatment of nonalcoholic fatty liver disease in children: TONIC trial design

Joel E. Lavine; Jeffrey B. Schwimmer; Jean P. Molleston; Ann O. Scheimann; Karen F. Murray; Stephanie H. Abrams; Philip J. Rosenthal; Arun J. Sanyal; Patricia R. Robuck; Elizabeth M. Brunt; Aynur Unalp; James Tonascia

BACKGROUND Nonalcoholic fatty liver disease (NAFLD) in children can lead to steatohepatitis, cirrhosis, and end-stage liver disease. The cause of NAFLD is unknown, but it is commonly associated with obesity, insulin resistance, and dyslipidemia. OBJECTIVES TONIC is conducted to test whether treatment with metformin, an insulin sensitizer, or vitamin E, a naturally available antioxidant, will lead to improvements in biochemical and histological features of nondiabetic children with biopsy-proven NAFLD. DESIGN TONIC is a randomized, multicenter, double-masked, placebo-controlled trial of 96 weeks of treatment with metformin or vitamin E. The primary outcome measure chosen for the trial is improvement in serum alanine aminotransferase (ALT) levels with treatment as compared to placebo. An improvement in ALT is defined as reduction in serum ALT levels to below 50% of the baseline values or into the normal range (40 U/L or less) during the last 48 weeks of treatment. Histological improvement is defined by changes in liver histology between a baseline and end-of-treatment liver biopsy in regards to (1) steatohepatitis, (2) NAFLD Activity Score, consisting of scores for steatosis, lobular inflammation, and hepatocellular injury (ballooning), and (3) fibrosis score. METHODS Between September 2005 and September 2007, 173 children were enrolled into TONIC at 10 clinical centers in the United States. Participants were randomized to receive either metformin (500 mg b.i.d.), vitamin E (400 IU b.i.d.), or placebo for 96 weeks. This protocol was approved by all participating center Institutional Review Boards (IRBs) and an independent Data and Safety Monitoring Board (DSMB). (ClinicalTrials.gov number, NCT00063635.).


American Journal of Physiology-gastrointestinal and Liver Physiology | 2009

Macropinocytosis in Shiga toxin 1 uptake by human intestinal epithelial cells and transcellular transcytosis

Irina Malyukova; Karen F. Murray; Chengru Zhu; Edgar C. Boedeker; Anne Kane; Kathleen Patterson; Jeffrey R. Peterson; Mark Donowitz; Olga Kovbasnjuk

Shiga toxin 1 and 2 production is a cardinal virulence trait of enterohemorrhagic Escherichia coli infection that causes a spectrum of intestinal and systemic pathology. However, intestinal sites of enterohemorrhagic E. coli colonization during the human infection and how the Shiga toxins are taken up and cross the globotriaosylceramide (Gb3) receptor-negative intestinal epithelial cells remain largely uncharacterized. We used samples of human intestinal tissue from patients with E. coli O157:H7 infection to detect the intestinal sites of bacterial colonization and characterize the distribution of Shiga toxins. We further used a model of largely Gb3-negative T84 intestinal epithelial monolayers treated with B-subunit of Shiga toxin 1 to determine the mechanisms of non-receptor-mediated toxin uptake. We now report that E. coli O157:H7 were found at the apical surface of epithelial cells only in the ileocecal valve area and that both toxins were present in large amounts inside surface and crypt epithelial cells in all tested intestinal samples. Our in vitro data suggest that macropinocytosis mediated through Src activation significantly increases toxin endocytosis by intestinal epithelial cells and also stimulates toxin transcellular transcytosis. We conclude that Shiga toxin is taken up by human intestinal epithelial cells during E. coli O157:H7 infection regardless of the presence of bacterial colonies. Macropinocytosis might be responsible for toxin uptake by Gb3-free intestinal epithelial cells and transcytosis. These observations provide new insights into the understanding of Shiga toxin contribution to enterohemorrhagic E. coli-related intestinal and systemic diseases.


JAMA | 2014

Use of Corticosteroids After Hepatoportoenterostomy for Bile Drainage in Infants With Biliary Atresia: The START Randomized Clinical Trial

Jorge A. Bezerra; Cathie Spino; John C. Magee; Benjamin L. Shneider; Philip J. Rosenthal; Kasper S. Wang; Jessi Erlichman; Barbara Haber; Paula M. Hertel; Saul J. Karpen; Nanda Kerkar; Kathleen M. Loomes; Jean P. Molleston; Karen F. Murray; Rene Romero; Kathleen B. Schwarz; R. W. Shepherd; Frederick J. Suchy; Yumirle P. Turmelle; Peter F. Whitington; Jeffrey S. Moore; Averell H. Sherker; Patricia R. Robuck; Ronald J. Sokol

IMPORTANCE Biliary atresia is the most common cause of end-stage liver disease in children. Controversy exists as to whether use of steroids after hepatoportoenterostomy improves clinical outcome. OBJECTIVE To determine whether the addition of high-dose corticosteroids after hepatoportoenterostomy is superior to surgery alone in improving biliary drainage and survival with the native liver. DESIGN, SETTING, AND PATIENTS The multicenter, double-blind Steroids in Biliary Atresia Randomized Trial (START) was conducted in 140 infants (mean age, 2.3 months) between September 2005 and February 2011 in the United States; follow-up ended in January 2013. INTERVENTIONS Participants were randomized to receive intravenous methylprednisolone (4 mg/kg/d for 2 weeks) and oral prednisolone (2 mg/kg/d for 2 weeks) followed by a tapering protocol for 9 weeks (n = 70) or placebo (n = 70) initiated within 72 hours of hepatoportoenterostomy. MAIN OUTCOMES AND MEASURES The primary end point (powered to detect a 25% absolute treatment difference) was the percentage of participants with a serum total bilirubin level of less than 1.5 mg/dL with his/her native liver at 6 months posthepatoportoenterostomy. Secondary outcomes included survival with native liver at 24 months of age and serious adverse events. RESULTS The proportion of participants with improved bile drainage was not statistically significantly improved by steroids at 6 months posthepatoportoenterostomy (58.6% [41/70] of steroids group vs 48.6% [34/70] of placebo group; adjusted relative risk, 1.14 [95% CI, 0.83 to 1.57]; P = .43). The adjusted absolute risk difference was 8.7% (95% CI, -10.4% to 27.7%). Transplant-free survival was 58.7% in the steroids group vs 59.4% in the placebo group (adjusted hazard ratio, 1.0 [95% CI, 0.6 to 1.8]; P = .99) at 24 months of age. The percentage of participants with serious adverse events was 81.4% [57/70] of the steroids group and 80.0% [56/70] of the placebo group (P > .99); however, participants receiving steroids had an earlier time of onset of their first serious adverse event by 30 days posthepatoportoenterostomy (37.2% [95% CI, 26.9% to 50.0%] of steroids group vs 19.0% [95% CI, 11.5% to 30.4%] of placebo group; P = .008). CONCLUSIONS AND RELEVANCE Among infants with biliary atresia who have undergone hepatoportoenterostomy, high-dose steroid therapy following surgery did not result in statistically significant treatment differences in bile drainage at 6 months, although a small clinical benefit could not be excluded. Steroid treatment was associated with earlier onset of serious adverse events in children with biliary atresia. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00294684.

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Kathleen B. Schwarz

Johns Hopkins University School of Medicine

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Maureen M. Jonas

Boston Children's Hospital

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Michael R. Narkewicz

University of Colorado Denver

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