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Dive into the research topics where Robert O. Newbury is active.

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Featured researches published by Robert O. Newbury.


Hepatology | 2005

Histopathology of pediatric nonalcoholic fatty liver disease

Jeffrey B. Schwimmer; Cynthia Behling; Robert O. Newbury; Reena Deutsch; Caroline M. Nievergelt; Nicholas J. Schork; Joel E. Lavine

Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are common in children and adolescents. However, standard histological criteria for pediatric NAFLD and NASH are undeveloped. We reviewed consecutive patients ages 2 to 18 years with biopsy‐proven NAFLD diagnosed between 1997 and 2003. Biopsies were evaluated by two pathologists for individual features of steatohepatitis. Agglomerative hierarchical cluster analysis demonstrated two different forms of steatohepatitis. Type 1 was characterized by steatosis, ballooning degeneration, and perisinusoidal fibrosis; type 2 was characterized by steatosis, portal inflammation, and portal fibrosis. The study included 100 children with NAFLD. Simple steatosis was present in 16% of subjects, and advanced fibrosis was present in 8%. Type 1 NASH was present in 17% of subjects, and type 2 NASH was present in 51%. Boys were significantly (P < .01) more likely to have type 2 NASH and less likely to have type 1 NASH than girls. The NASH type differed significantly (P < .001) by race and ethnicity. Type 1 NASH was more common in white children, whereas type 2 NASH was more common in children of Asian, Native American, and Hispanic ethnicity. In cases of advanced fibrosis, the pattern was generally that of type 2 NASH. In conclusion, type 1 and type 2 NASH are distinct subtypes of pediatric NAFLD, and type 2 is the most common pattern in children. NASH subtypes should be considered when interpreting liver biopsies and planning studies of the pathophysiology, genetics, natural history, or response to treatment in pediatric NAFLD. (HEPATOLOGY 2005;42:641–649.)


The Journal of Pediatrics | 2003

Obesity, insulin resistance, and other clinicopathological correlates of pediatric nonalcoholic fatty liver disease.

Jeffrey B. Schwimmer; Reena Deutsch; Jeffrey B Rauch; Cynthia Behling; Robert O. Newbury; Joel E. Lavine

OBJECTIVE To describe the clinical characteristics of nonalcoholic fatty liver disease (NAFLD) in children, including insulin resistance, and to test for correlation with liver pathology. STUDY DESIGN A retrospective review of children with biopsy-proven NAFLD at Childrens Hospital San Diego from 1999 to 2002. Liver biopsy specimens were independently reviewed by two pathologists. RESULTS Children with NAFLD (n=43) were mostly male (70%), Hispanic American (53%) and obese (88%). The criteria for insulin resistance were met by 95% of subjects. Steatosis was predicted by the combination of quantitative insulin sensitivity check index, age, and ethnicity (P<.0001). Portal inflammation was predicted by the combination of ALT and fasting insulin (P=.0009). Perisinusoidal fibrosis was predicted by the combination of AST, fasting insulin, and BMI Z score (P<.0001). Portal fibrosis was predicted by the combination of right upper quadrant pain and homeostasis model assessment of insulin resistance (P=.0028). CONCLUSIONS We identified significant predictors of liver pathology in children with NAFLD. Children being evaluated for NAFLD should be screened for insulin resistance, which is nearly universal and correlates with liver histology.


Gastroenterology | 2010

Oral Viscous Budesonide Is Effective in Children With Eosinophilic Esophagitis in a Randomized, Placebo-Controlled Trial

Ranjan Dohil; Robert O. Newbury; Lyman Fox; John F. Bastian; Seema S. Aceves

BACKGROUND & AIMS Eosinophilic esophagitis (EoE) is caused by immunologic reactions to ingested/inhaled allergens. The diagnosis is considered if >or=15 eosinophils per high-powered field (eos/hpf) are detected in mucosal biopsies. Placebo-controlled studies have not been conducted to evaluate the safety and efficacy of oral viscous budesonide (OVB). METHODS Children with EoE were randomly assigned to groups that were given OVB (n=15) or placebo (n=9). Patients<5 feet and >or=5 feet tall received 1 mg and 2 mg OVB daily, respectively. All patients received lansoprazole. Duration of treatment was 3 months, followed by repeat endoscopy and biopsies. Patients were classified as responders if their peak eosinophil counts were <or=6 eos/hpf, partial responders were 7-19 eos/hpf, and nonresponders were >or=20 eos/hpf. Baseline and post-treatment symptoms and endoscopic and histologic features were scored. RESULTS Thirteen (86.7%) children given OVB (P<.0001) and none who received placebo (P=.3) were classified as responders. Mean pre-/post-treatment peak eosinophil counts were 66.7 and 4.8 eos/hpf, respectively, in the group given OVB (P<.0001); they were 83.9 and 65.6 eos/hpf, respectively, in the group given placebo (P=.3). In the group given OVB, there were significant reductions from baseline values in proximal (P=.002), mid (P=.0003), and distal (P=.001) esophageal eosinophilia. After OVB therapy, compared with baseline, the mean symptom (P=.0007), endoscopy (P=.0005), and histology scores improved (P=.0035) significantly. CONCLUSIONS OVB is an effective treatment of pan-esophageal disease in children with EoE. OVB improves symptoms and endoscopic and histologic features. Proton pump inhibitor single therapy did not significantly improve esophageal eosinophilia or symptoms of EoE.


Allergy | 2010

Resolution of remodeling in eosinophilic esophagitis correlates with epithelial response to topical corticosteroids

Seema S. Aceves; Robert O. Newbury; D. Chen; J. Mueller; Ranjan Dohil; H. Hoffman; John F. Bastian; David H. Broide

Background:  Esophageal remodeling occurs in eosinophilic esophagitis (EE) patients but whether the components of remodeling in the subepithelium are reversible by administration of topical oral corticosteroids is unknown.


The American Journal of Gastroenterology | 2007

Oral Viscous Budesonide: A Potential New Therapy for Eosinophilic Esophagitis in Children

Seema S. Aceves; John F. Bastian; Robert O. Newbury; Ranjan Dohil

BACKGROUND:Eosinophilic esophagitis (EE) is a disorder characterized typically by pan-esophageal eosinophilia. We evaluate a palatable, long-acting topical corticosteroid preparation for the treatment of EE.STUDY DESIGN:This is a retrospective analysis of symptoms, endoscopic and histologic findings, efficacy, and safety of treatment in children with EE receiving oral viscous budesonide. Response to therapy was determined histologically by the number of eos/hpf. Patients were classified by histology into responders (0–7 eos/hpf), partial responders (8–23 eos/hpf), and nonresponders (≥24 eos/hpf). A symptom score (max. 14) and an EE endoscopy score (max. 8) were used to compare data.RESULTS:In 20 children (mean age 5.5 yr, median age 4.1 yr) the mean highest eosinophil count was 87 eos/hpf (range 30–170) before and 7 eos/hpf (range 0–50, P < 0.0001) after therapy. There were 16 (80%) responders, 1 partial responder, and 3 nonresponders. Commonest pretreatment symptoms were nausea, vomiting, pain, and heartburn. The mean symptom score fell from 4.4 to 0.8 (P < 0.0001) and the mean endoscopy score from 3.6 to 0.8 (P < 0.0001). No significant adverse events were reported. Morning cortisol levels were within normal limits.CONCLUSIONS:Topical viscous budesonide is a safe and effective therapy for EE in young children.


The Journal of Allergy and Clinical Immunology | 2010

Mast cells infiltrate the esophageal smooth muscle in patients with eosinophilic esophagitis, express TGF-β1, and increase esophageal smooth muscle contraction

Seema S. Aceves; Diana Chen; Robert O. Newbury; Ranjan Dohil; John F. Bastian; David H. Broide

BACKGROUND Increased numbers of mast cells are present in the esophageal epithelium in patients with eosinophilic esophagitis (EE). However, mast cell infiltration into the esophageal lamina propria (LP) and smooth muscle (SM) and the effects of their products on SM function has not been determined. OBJECTIVE We investigated mast cell localization and characterization in esophageal SM, the functional significance of mast cell TGF-β1 expression to contraction of human esophageal smooth muscle (HESM) cells in vitro, and the effect of topical corticosteroids on the number of tryptase-positive (MC(T)) and chymase-positive (MC(C)) mast cells in patients with EE. METHODS MC(T)- and MC(C)-positive mast cell numbers were quantitated in the epithelium, the LP before and after topical corticosteroid therapy, and the muscularis mucosa in patients with EE and control subjects by using immunohistology. Double immunofluorescence was used to assess mast cell production of TGF-β1. The ability of TGF-β1 to influence HESM cell contractility was assessed in vitro. RESULTS In the SM in patients with EE, significantly increased numbers of MC(T)- and TGF-β1-positive cells (but only low levels of eosinophils) were detected compared with those seen in control subjects. MC(T) expressed TGF-β1, which increased the contractility of cultured primary HESM cells in vitro. Topical corticosteroid therapy in patients with EE significantly reduced epithelial MC(T) numbers but not LP tryptase-chymase-positive mast cell numbers. CONCLUSIONS MC(T) numbers, rather than eosinophil numbers, are increased in the SM in patients with EE, express TGF-β1, and increase the contractility of HESM cells in vitro. As such, mast cells localized to SM in patients with EE might modulate esophageal contractility.


Journal of Clinical Gastroenterology | 2007

Distinguishing eosinophilic esophagitis in pediatric patients: clinical, endoscopic, and histologic features of an emerging disorder.

Seema S. Aceves; Robert O. Newbury; Ranjan Dohil; Jeffrey B. Schwimmer; John F. Bastian

Goals To determine the clinical, endoscopic, and histologic criteria that distinguish children with eosinophilic esophagitis (EE) from those with non-EE diagnoses. Background EE is a disease of escalating incidence. Distinguishing children with EE from those with non-EE diagnosis can be difficult before endoscopy. Study A retrospective case-control study was performed for children with any degree of esophageal eosinophilic inflammation who underwent esophageal biopsy at Childrens Hospital San Diego from January 1998 to December 2002. A database containing children who met histologic criteria for EE and an equivalent number of children who had milder esophageal eosinophilia (non-EE patients) was created to compare the 2 groups. Results The number of EE cases increased from 15 in 1998 to 35 in 2002. EE patients were predominantly school-aged boys; 5 of 102 were suspected to have EE before biopsy. Although EE and non-EE patients complained of vomiting and abdominal pain at equivalent rates, EE patients were 3 times more likely to complain of dysphagia [odds ratio (OR)=3.11, 95% confidence interval (CI) 1.55-6.65] and twice as likely to have stricture formation (OR=2.43, 95% CI 0.72-11.75). On endoscopy, patients with EE were 19-times more likely than non-EE patients to have endoscopic abnormalities (OR=19, 95% CI 9.0-45.88). Histologically, EE patients were more likely to have basal zone hyperplasia and degranulated eosinophils (OR=45 and 157, respectively). Conclusions We demonstrate that school-aged children, particularly boys, who complain of dysphagia should raise the index of suspicion for EE. We also suggest that EE-associated strictures are more common than peptic strictures in children.


Gastroenterology | 2008

Identification of EpCAM as the Gene for Congenital Tufting Enteropathy

Mamata Sivagnanam; James L. Mueller; Hane Lee; Zugen Chen; Stanley F. Nelson; Dan Turner; Stanley Zlotkin; Paul B. Pencharz; Bo-Yee Ngan; Ondrej Libiger; Nicholas J. Schork; Joel E. Lavine; Sharon F. Taylor; Robert O. Newbury; Richard D. Kolodner; Hal M. Hoffman

BACKGROUND & AIMS Congenital tufting enteropathy (CTE) is a rare autosomal recessive diarrheal disorder presenting in the neonatal period. CTE is characterized by intestinal epithelial cell dysplasia leading to severe malabsorption and significant morbidity and mortality. The pathogenesis and genetics of this disorder are not well understood. The objective of this study was to identify the gene responsible for CTE. METHODS A family with 2 children affected with CTE was identified. The affected children are double second cousins providing significant statistical power for linkage. Using Affymetrix 50K single nucleotide polymorphism (SNP) chips, genotyping was performed on only 2 patients and 1 unaffected sibling. Direct DNA sequencing of candidate genes, reverse-transcription polymerase chain reaction, immunohistochemistry, and Western blotting were performed on specimens from patients and controls. RESULTS SNP homozygosity mapping identified a unique 6.5-Mbp haplotype of homozygous SNPs on chromosome 2p21 where approximately 40 genes are located. Direct sequencing of genes in this region revealed homozygous G>A substitution at the donor splice site of exon 4 in epithelial cell adhesion molecule (EpCAM) of affected patients. Reverse-transcription polymerase chain reaction of duodenal tissue demonstrated a novel alternative splice form with deletion of exon 4 in affected patients. Immunohistochemistry and Western blot of patient intestinal tissue revealed decreased expression of EpCAM. Direct sequencing of EpCAM from 2 additional unrelated patients revealed novel mutations in the gene. CONCLUSIONS Mutations in the gene for EpCAM are responsible for CTE. This information will be used to gain further insight into the molecular mechanisms of this disease.


Annals of Allergy Asthma & Immunology | 2009

A symptom scoring tool for identifying pediatric patients with eosinophilic esophagitis and correlating symptoms with inflammation.

Seema S. Aceves; Robert O. Newbury; Magdalene A. Dohil; John F. Bastian; Ranjan Dohil

BACKGROUND Eosinophilic esophagitis (EE) is an increasingly recognized allergic disease entity that is difficult to distinguish clinically from other causes of esophagitis, especially gastroesophageal reflux disease (GERD). To our knowledge, there are no prospectively analyzed or validated symptom scoring tools for pediatric patients with EE and no prospective evaluation correlating symptoms with tissue inflammation. OBJECTIVES To prospectively analyze a symptom scoring tools ability to distinguish pediatric patients with EE from those with GERD and from control patients with and without allergies and to correlate symptoms with tissue inflammation. METHODS A prospective study of a symptom scoring tool given to patients with EE (n = 35 not receiving EE targeted therapy), patients with GERD (n = 27 not undergoing acid suppression), allergic control patients (n = 24), and nonallergic control patients (n = 14) at an academic pediatric hospital. Histology and endoscopy scores were correlated with symptom complaints. RESULTS The total symptom score was higher among patients with EE (mean, 6.51; 95% confidence interval [CI], 5.50-7.53) and GERD (mean, 5.44; 95% CI, 4.64-6.25) than in allergic (mean, 0.92; 95% CI, 0.28-1.55) and nonallergic (mean, 1.00; 95% CI, 0.40-1.60) patients (P < .001). Patients with EE and GERD complained of more nausea/vomiting, abdominal pain, heartburn/regurgitation, and nocturnal awakening than control groups (P < .001). Only dysphagia (mean, 0.9 [95% CI, 0.7-1.2] in EE patients vs 0.4 [95% CI, 0.2-0.7] in GERD patients) and anorexia/early satiety (mean, 1.4 [95% CI, 1.2-1.6] in EE patients vs 0.8 [95% CI, 0.5-1.1] in GERD patients) discriminate EE from GERD (P < .01). These symptoms also correlated with the severity of histologic and endoscopic findings (P < .05). CONCLUSION Dysphagia and anorexia/early satiety identify pediatric patients with EE and correlate symptoms with tissue inflammation.


Pediatric Blood & Cancer | 2008

Treatment of Wilms tumor relapsing after initial treatment with vincristine, actinomycin D, and doxorubicin. A report from the national Wilms tumor study group

Marcio H. Malogolowkin; Cecilia A. Cotton; Daniel M. Green; Norman E. Breslow; Elizabeth J. Perlman; James S. Miser; Michael L. Ritchey; Patrick R. M. Thomas; Paul E. Grundy; Giulio J. D'Angio; J. Bruce Beckwith; Robert C. Shamberger; Gerald M. Haase; Milton Donaldson; Robert M. Weetman; Max J. Coppes; Patricia Shearer; Peter F. Coccia; Morris Kletzel; Roger M. Macklis; Gail E. Tomlinson; Vicki Huff; Robert O. Newbury; Douglas Weeks

We evaluated the use of alternating cycles of cyclophosphamide/etoposide and carboplatin/etoposide in children entered on National Wilms Tumor Study (NWTS)‐5 who were diagnosed between August 1, 1995 and May 31, 2002 and who relapsed after chemotherapy with vincristine, actinomycin D, and doxorubicin (VAD) and radiation therapy (DD‐4A).

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Ranjan Dohil

University of California

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John F. Bastian

Boston Children's Hospital

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Hal M. Hoffman

University of California

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Richard C. Kurten

University of Arkansas for Medical Sciences

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