We explore strategies to enhance conformational ordering of N-substituted glycine peptoid oligomers. Peptoids bearing bulky N-alkyl side chains have previously been studied as important examples of biomimetic "foldamer" compounds, as they exhibit a capacity to populate helical structures featuring repeating cis-amide bonds. Substantial cis/trans amide bond isomerization, however, gives rise to conformational heterogeneity. Here, we report the use of N-aryl side chains as a tool to enforce the presence of trans-amide bonds, thereby engendering structural stability. Aniline derivatives and bromoacetic acid are used in the facile solid-phase synthesis of a diverse family of sequence-specific N-aryl glycine oligomers. Quantum mechanics calculations yield a detailed energy profile of the folding landscape and substantiate the hypothesis that the presence of anilide groups establishes a strong energetic preference for trans-amide bonds. X-ray crystallographic analysis and solution NMR studies verify this preference. Molecular modeling indicates that the linear oligomers can adopt helical structures resembling a polyproline type II helix. High resolution structures of macrocyclic oligomers incorporating both N-alkyl and N-aryl glycine units confirm the ability to direct the presence of trans-amide bonds specifically at N-aryl positions. These results are an important step in developing strategies for the rational de novo design of new structural motifs in biomimetic oligopeptoid systems.

Renal dysfunction has been reported in patients treated with adefovir dipivoxil (ADV); however, its incidence and clinical importance may be underappreciated given the lack of long-term follow-up and data outside of a clinical trial setting. Our goal was to examine the severity and incidence of renal dysfunction in a real-life setting for patients treated with ADV and whose baseline estimated glomerular filtration rate (eGFR) was >50 mL/minute. We performed a cohort study of 290 chronic hepatitis B patients: 145 patients treated with 10 mg ADV and 145 patients unexposed to ADV at two community clinics, who were matched for age (؎10 years), sex, and baseline eGFR. The exposed and unexposed populations were well-matched with a similar mean age (46-47 years), proportion of male patients (76.5%), baseline serum creatinine (0.97-0.99 mg/dL), and baseline creatinine clearance (85.0-85.4 mL/minute). The incidence density for renal dysfunction defined by treatment termination and/or development of eGFR <50 mL/minute was five cases per 100 patient-years in the exposed group compared with 1.36 cases per 100 patient-years in the unexposed group (P ‫؍‬ 0.02). The relative risk of exposed to unexposed was 3.68 (95% confidence interval 1

Assignment of liver allocation priority for hepatocellular carcinoma is predicated on accurate imaging staging. We analyzed radiographically defined stage (radiologic stage [RS]) at listing and most recent extension and pathologic stage (PS) data from 789 liver transplant recipients for whom no pretransplant ablative treatment was given. There were no predetermined imaging or pathological protocols in this retrospective analysis of wait list data. Seventy-two (9.1%), 690 (87.5%), and 27 (3.4%) were listed as stage 1, 2 and Ͼ2, respectively. Computed tomography (CT) scan alone (46.4%), magnetic resonance image scan alone (37.1%), ultrasound alone (1.3%), and multiple imaging studies (15.2%) were used with no difference in time to transplant for listing or most recent scan among the recipient groups. Overall accuracy (RS ϭ PS) was 44.1% and was not different if original listing RS or most recent RS was used for comparison with PS. No one type of imaging technique had superior accuracy (P ϭ 0.13); however, CT scan used alone or in combination compared to not being used at all, had higher odds of being accurate (odds ratio [OR] See Editorial on Page 1445Liver transplantation for early-stage hepatocellular carcinoma (HCC) is more likely to provide a potential cure and improve survival than other less radical techniques. 1 These excellent results for liver transplantation depend on selection of patients with early, favorable-stage disease. Mazzafero et al. indicated that patients with single tumors less than 5 cm in size or 3 or fewer tumors no larger than 3 cm in size have excellent long-term recurrence-free survival. 2 This staging was based on histologic criteria evaluated in the explanted native liver retrospectively. Although this report summarized relatively few cases, many subsequent reports have confirmed that these so-called Milan criteria consistently identify HCC disease with favorable prognosis after liver transplantation. 3,4 How-

Patients with CHB, high HBV DNA, and NLALT levels and aged more than 35 years or those with FLALT levels may have significant histological disease (22-70%).

Despite consolidation therapy, almost all patients who discontinued therapy after achieving HBeAg seroconversion and complete viral suppression experienced recurrent viremia, and close to half also experienced biochemical flares. HBeAg seroconversion does not seem to be a durable treatment endpoint for many patients, and they should be monitored carefully for virologic relapse and biochemical flares if antiviral therapy is withdrawn.