Routine use of thiopurines in maintaining remission in pediatric Crohn's disease

AIM: To evaluate the effectiveness of thiopurines in maintaining steroid-free remission in routine clinical practice. METHODS: The multi-center Pediatric Inflammatory Bowel Disease Network (PIBDNet) cohort study prospectively collected data on thiopurine naïve patients initiating mercaptopurine (6MP) or azathioprine. Patients with a diagnosis of Crohn's disease (CD) were included in our study upon entering remission as determined by physician global assessment (PGA) within 365 d of initiation of thiopurines. The primary outcome of the study was maintenance of steroid-free remission (SFR) at each follow up visit. Patients were considered treatment failures if there had been a change in PGA from remission to mild, moderate or severe disease; disease relapse between visits; need for rescue therapy (biologic therapy, methotrexate, steroids); thiopurine discontinuation, hospitalization or surgical intervention. A secondary outcome defined treatment failure as a change from remission to moderate or severe (not mild) in addition to the previously defined criteria. RESULTS: Sixty-five of 182 patients in the PIBDNet registry met criteria for inclusion in this study. Forty-five of 65 (69%) of included patients achieved remission within 180 d of thiopurine initiation. For the primary outcome, 47% and 23% of patients remained in SFR at 6 and 12 mo. The mean thiopurine dose at initiation for the 65 included patients was 0.89 ± 0.31 mg/kg per day. Metabolite levels were obtained in 48% (31/65) of the included patients with a mean 6TG level of 258 pmole/8 × 108RBC ± 147. For the secondary outcome, 65% and 42% of patients remained in SFR at 6 and 12 mo. CONCLUSION: Thiopurines were less effective in maintaining remission for pediatric CD in this "real world" cohort than has been previously described. Variation in thiopurine dosing and metabolite measurement was found among practitioners

Organic film thickness influence on the bias stress instability in Sexithiophene Field Effect Transistors

In this paper, the dynamics of bias stress phenomenon in Sexithiophene (T6) Field Effect Transistors (FETs) has been investigated. T6 FETs have been fabricated by vacuum depositing films with thickness from 10 nm to 130 nm on Si/SiO2 substrates. After the T6 film structural analysis by X-Ray diffraction and the FET electrical investigation focused on carrier mobility evaluation, bias stress instability parameters have been estimated and discussed in the context of existing models. By increasing the film thickness, a clear correlation between the stress parameters and the structural properties of the organic layer has been highlighted. Conversely, the mobility values result almost thickness independent

Spacetime Coarse Grainings in the Decoherent Histories Approach to Quantum Theory

We investigate the possibility of assigning consistent probabilities to sets of histories characterized by whether they enter a particular subspace of the Hilbert space of a closed system during a given time interval. In particular we investigate the case that this subspace is a region of the configuration space. This corresponds to a particular class of coarse grainings of spacetime regions. We consider the arrival time problem and the problem of time in reparametrization invariant theories as for example in canonical quantum gravity. Decoherence conditions and probabilities for those application are derived. The resulting decoherence condition does not depend on the explicit form of the restricted propagator that was problematic for generalizations such as application in quantum cosmology. Closely related is the problem of tunnelling time as well as the quantum Zeno effect. Some interpretational comments conclude, and we discuss the applicability of this formalism to deal with the arrival time problem.Comment: 23 pages, Few changes and added references in v

Viscosity Solutions to Delay Differential Equations in Demo-Economy

Economic and demographic models governed by linear delay differential equations are expressed as optimal control problems in infinite dimensions. A general objective function is considered and the concavity of the Hamiltonian is not required. The value function is a viscosity solution of the Hamilton-Jacobi-Bellman (HJB) equation and a verification theorem is proved.delay differential equation, vintage models, viscosity solutions,