Citations

Abstract A phase I trial of ABT-888 (veliparib), a PARP inhibitor, in combination with topotecan, a topoisomerase I–targeted agent, was carried out to determine maximum tolerated dose (MTD), safety, pharmacokinetics, and pharmacodynamics of the combination in patients with refractory solid tumors and lymphomas. Varying schedules and doses of intravenous topotecan in combination with ABT-888 (10 mg) administered orally twice a day (BID) were evaluated. Plasma and urine pharmacokinetics were assessed and levels of poly(ADP-ribose) (PAR) and the DNA damage marker γH2AX were measured in tumor and peripheral blood mononuclear cells (PBMC). Twenty-four patients were enrolled. Significant myelosuppression limited the ability to coadminister ABT-888 with standard doses of topotecan, necessitating dose reductions. Preclinical studies using athymic mice carrying human tumor xenografts also informed schedule changes. The MTD was established as topotecan 0.6 mg/m2/d and ABT-888 10 mg BID on days one to five of 21-day cycles. Topotecan did not alter the pharmacokinetics of ABT-888. A more than 75% reduction in PAR levels was observed in 3 paired tumor biopsy samples; a greater than 50% reduction was observed in PBMCs from 19 of 23 patients with measurable levels. Increases in γH2AX response in circulating tumor cells (CTC) and PBMCs were observed in patients receiving ABT-888 with topotecan. We show a mechanistic interaction of a PARP inhibitor, ABT-888, with a topoisomerase I inhibitor, topotecan, in PBMCs, tumor, and CTCs. Results of this trial reveal that PARP inhibition can modulate the capacity to repair topoisomerase I–mediated DNA damage in the clinic. Cancer Res; 71(17); 5626–34. ©2011 AACR.

ABSTRACTBackground:The relations between hepatic steatosis and histological features of hepatocyte injury in children with nonalcoholic fatty liver disease have yet to be examined. The aims of the present study were to establish associations between steatosis amount, type, and distribution in a well‐characterized group of children with biopsy‐proven nonalcoholic fatty liver disease (NAFLD).Patients and Methods:One hundred eight children with NAFLD seen in 5 centers were studied. Clinical and laboratory data were collected. Hematoxylin‐eosin and Masson trichrome stains were evaluated by 2 expert liver pathologists. Steatosis grade (0–3), type (macrovesicular, microvesicular, or mixed), and zone (1, 3, azonal, or panacinar) were determined. The NAFLD activity score and fibrosis stage were determined.Results:Median patient age was 12 years and median body mass index was 31 kg/m2. Fibrosis was present in 87%. The median NAFLD activity score was 4. Mild, moderate, and severe steatosis were present in 42%, 34%, and 24% of biopsies, respectively. Macrovesicular steatosis was present in 81% and mixed steatosis was present in 19%. Panacinar distribution of steatosis was most frequent (40%), followed by azonal (27%). Steatosis grade positively correlated with portal inflammation (P = 0.018). Azonal distribution positively correlated with presence of hepatocyte ballooning (P = 0.03). Biopsies with mixed steatosis were approximately 20 times more likely to have megamitochondria than those with macrovesicular steatosis alone (95% confidence interval 2.3–204.9). There was no relation between steatosis amount, type, or distribution to fibrosis stage.Conclusions:Specific histological patterns of steatosis in children are associated with histological markers of steatohepatitis. Ballooning and portal inflammation correlated well with features of steatosis.

Objective: This 8-week, open-label trial assessed the efficacy of methylphenidate transdermal system (MTS) in 14 adult individuals diagnosed with ADHD and with a history of stimulant misuse, abuse, or dependence. Method: The primary efficacy endpoint was the Wender-Reimherr Adult ADHD Scale (WRAADS), and secondary efficacy endpoints included the Clinical Global Impression (CGI) ratings and substance abuse as quantified by urine drug screens and self-reported use. Results: Significant improvements from baseline were found on both the WRAADS and CGI measurements. No abuse of the study medication was observed. Conclusion: The findings suggested that MTS may improve ADHD symptoms in adults with a history of stimulant misuse; however, there were limitations. The study data showed the need for subsequent randomized studies that further explore findings made in this study.

SummaryClinical trials often include binary end points. In some cases, no successes are observed and the usual large sample estimates of relative risk are undefined. The paper proposes an estimator for relative risk based on the median unbiased estimator. The relative risk estimator proposed is well defined and performs satisfactorily for a wide range of data configurations. To facilitate the use of the estimator, a deterministic bootstrap confidence interval is also proposed, and an SAS macro is available to perform the necessary calculations. An on-going randomized clinical trial motivated the development of the estimator and is used to illustrate the approach.

Objective: To describe a case of severe sepsis, cavitary pneumonia, and pyomyositis caused by Arcanobacterium haemolyticum. Case Summary: An 18-year-old male with a medical history significant for mild asthma presented to the emergency department complaining of a 7-day history of fever, diffuse myalgias, nausea, vomiting, diarrhea, and pain in his right upper quadrant, right shoulder, and left thigh. Cultures of blood, bronchoalveolar fluid, and suríace and surgical swabs from the patient's left lower extremity grew A haemolyticum. The patient was successfully treated with intravenous penicillin G 4 million units every 4 hours and azithromycin 500 mg onca daily for 14 days. Within 36 hours after initiation of focused therapy, he became afebrile, pain decreased, and pulmonary symptoms abated. Oral azithromycin 500 mg/day for an additional 3 weeks was prescribed on discharge, and the patient showed no relapse at 2-month follow-up. Discussion: A. haemolyticum Is a weakly acid-fast, branching gram-positive bacillus most commonly implicated in pharyngitis in healthy adolescents and skin and soft-tissue infections in older, immunocompromised patients. Systemic infections are rarely reported in the literature. This organism remains susceptible to most classes of antimicrobials, Including penicillins, cephalosporins, carba-penems, macrolides, tetracyclines, clindamycin, and vancomycin. Routine resistance has been reported only with trimethoprim/sulfamethoxazole. Conclusions: To our knowledge, there are no published case reports of severe sepsis caused by A. haemolyticum. While treatment options are numerous, we recommend (he use of intravenous penicillin or a cephalosporin as first-line pharmacologic management of deep-seated infections caused by this rare organism.