Durability of sustained response shown in paediatric patients with chronic hepatitis C who were treated with interferon alfa-2b plus ribavirin

Long-term studies in adults indicate that sustained virologic response (SVR) after combination treatment for chronic hepatitis C (CHC) predicts long-term clearance. Although peginterferon plus ribavirin is now standard care for children with CHC, long-term follow-up studies are not yet available. This study evaluated durability of virologic response over 5 years in children previously treated with interferon alfa-2b plus ribavirin (IFN/R). Ninety-seven of 147 children with CHC, who were treated with IFN/R and completed the 6-month follow-up in two previous clinical trials, participated in this long-term follow-up study. All were assessed annually for up to 5 years; patients with SVR were assessed for durability of virologic response. Children with SVR (n = 56) and those with detectable hepatitis C virus (HCV) RNA 24-week post-treatment (n = 41) were followed for a median of 284 weeks. Overall, 70% (68/97) of patients completed the 5-year follow-up. One patient with genotype 1a CHC had SVR and relapsed at year 1 of follow-up with the same genotype. Kaplan-Meier estimate for sustained response at 5 years was 98% (95% CI: 95%, 100%). Six patients with low-positive HCV RNA levels (n = 4) or missing HCV RNA at the 24-week follow-up visit (n = 2) in the initial treatment studies had virologic response during this long-term follow-up study. Linear growth rate was impaired during treatment with rapid increases in the immediate 6 months post-treatment. Mean height percentile at the end of the 5-year follow-up was slightly less than the mean pretreatment height percentile. Five patients experienced serious adverse events; none related to study drug exposure. SVR after IFN/R predicts long-term clearance of HCV in paediatric patients; growth normalized in the majority of children during the long-term follow-up. Similar long-term results could be expected after peginterferon alfa-2b plus ribavirin treatment.

Synthesis, structural characterization, antimicrobial and cytotoxic effects of aziridine, 2-aminoethylaziridine and azirine complexes of copper(II) and palladium(II)

The synthesis, spectroscopic and X-ray structural characterization of copper(II) and palladium(II) complexes with aziridine ligands as 2-dimethylaziridine HNCH(2)CMe(2) (a), the bidentate N-(2-aminoethyl)aziridines C(2)H(4)NC(2)H(4)NH(2) (b) or CH(2)CMe(2)NCH(2)CMe(2)NH(2) (c) as well as the unsaturated azirine NCH(2)CPh (d) are reported. Cleavage of the cyclometallated Pd(II) dimer [μ-Cl(C(6)H(4)CHMeNMe(2)-C,N)Pd](2) with ligand a yielded compound [Cl(NHCH(2)CMe(2))(C(6)H(4)CHMe(2)NMe(2)-C,N)Pd] (1a). The reaction of the aziridine complex trans-[Cl(2)Pd(HNC(2)H(4))(2)] with an excess of aziridine in the presence of AgOTf gave the ionic chelate complex trans-[(C(2)H(4)NC(2)H(4)NH(2)-N,N')(2)Pd](OTf)(2) (2b) which contains the new ligand b formed by an unexpected insertion and ring opening reaction of two aziridines ("aziridine dimerization"). CuCl(2) reacted in pure HNC(2)H(4) or HNCH(2)CMe(2) (b) again by "dimerization" to give the tris-chelated ionic complex [Cu(C(2)H(4)NC(2)H(4)NH(2)-N,N')(3)]Cl(2) (3b) or the bis-chelated complex [CuCl(C(2)H(2)Me(2)NC(2)H(2)Me(2)NH(2)-N,N')(2)]Cl (4c). By addition of 2H-3-phenylazirine (d) to PdCl(2), trans-[Cl(2)Pd(NCH(2)CPh)(2)] (5d) was formed. All new compounds were characterized by NMR, IR and mass spectra and also by X-ray structure analyses (except 3b). Additionally the cytotoxic effects of these complexes were examined on HL-60 and NALM-6 human leukemia cells and melanoma WM-115 cells. The antimicrobial activity was also determined. The growth of Gram-positive bacterial strains (S. aureus, S. epidermidis, E. faecalis) was inhibited by almost all tested complexes at the concentrations of 37.5-300.0 μg mL(-1). However, MIC values of complexes obtained for Gram-negative E. coli and P. aeruginosa, as well as for C. albicans yeast, mostly exceeded 300 μg mL(-1). The highest antibacterial activity was achieved by complexes 1a and 2b. Complex 2b also inhibited the growth of Gram-negative bacteria.

[Evaluation of radiation dose in 64-row whole-body CT of multiple injured patients compared to 4-row CT]

PURPOSE

To evaluate radiation exposure in whole-body CT (WBCT) of multiple injured patients comparing 4-row multidetector computed tomography (MDCT) to 64-row MDCT.

MATERIALS AND METHODS

200 WBCT studies were retrospectively evaluated: 92 4-row MDCT scans and 108 64-row MDCT scans. Each CT protocol was optimized for the particular CT system. The scan length, CT dose index (CTDI), and dose length product (DLP) were recorded and analyzed for radiation exposure. The mean effective dose was estimated based on conversion factors. Student's t-test was used for statistical analysis.

RESULTS

The mean CTDIvol values (mGy) of the thorax and abdomen were significantly reduced with 64-row MDCT (10.2±2.5 vs. 11.4±1.4, p<0.001; 14.2±3.7 vs. 16.1±1.7, p<0.001). The DLP values (mGy×cm) of the head and thorax were significantly increased with 64-row MDCT (1305.9±201.1 vs. 849.8±90.9, p<0,001; 504.4±134.4 vs. 471.5±74.1, p=0.030). The scan lengths (mm) were significantly increased with 64-row MDCT: head 223.6±35.8 vs. 155.5±12.3 (p<0.001), thorax 427.4±44.5 vs. 388.3±57.5 (p<0.001), abdomen 520.3±50.2 vs. 490.8±51.6 (p<0.001). The estimated mean effective doses (mSv) were 22.4±2.6 (4-row MDCT) and 24.1±4.6 (64-row MDCT; p=0.001), resulting in a percentage increase of 8%.

CONCLUSION

The radiation dose per slice of the thorax and abdomen can be significantly decreased by using 64-row MDCT. Due to the technical advances of modern 64-row MDCT systems, the scan field can be adapted to the clinical demands and, if necessary, enlarged without time loss. As a result, the estimated mean effective dose might be increased in WBCT.

[Expert opinion on boceprevir- and telaprevir-based triple therapies of chronic hepatitis C]

With the approval of boceprevir and telaprevir the standard treatment of chronic hepatitis C virus (HCV) genotype 1 infection will be the triple therapy of a HCV protease inhibitor together with pegylated interferon alfa and ribavirin. In clinical studies a significant increase of sustained virological response rates from 38 - 44 % to 63 - 75 % for treatment-naïve and from 17 - 21 % to 59 - 66 % in treatment-experienced patients in comparison to the dual combination therapy with pegylated interferon alfa and ribavirin alone has been demonstrated. In addition, a large number of treatment-naïve patients and relapsers benefit from shorten treatment durations to 24 - 28 weeks. However, important differences exist between the administration of boceprevir and telaprevir in terms of a pegylated interferon alfa/ribavirin lead-in phase, the duration of dosing of the protease inhibitor, the overall treatment duration, HCV RNA measurements for response guided treatment durations and stopping rules. Furthermore, triple therapies with boceprevir and telaprevir may be associated with selection of resistant viral variants, new adverse events and clinically relevant drug-drug interactions. The present review gives an overview on the results of underlying clinical studies together with a guideline for the practical management of boceprevir- and telaprevir-based triple therapies.

Intestinal alpha-defensin expression in pediatric inflammatory bowel disease

BACKGROUND

Reduced alpha-defensin expression has been reported in the terminal ileum (TI) of adult patients with ileal Crohn's disease (CD). However, little is known about alpha-defensin expression in children with chronic inflammatory bowel disease (IBD).

METHODS

In all, 283 intestinal biopsies were obtained from children with CD, ulcerative colitis (UC), and healthy controls. Absolute mRNA copy numbers for HD5, HD6, IL-8, Villin 1, and Tcf-4 were analyzed by reverse-transcription polymerase chain reaction (RT-PCR). HD5 immunostaining was performed on biopsy sections and patients genotyped for NOD2 mutations.

RESULTS

Equal expression levels of alpha-defensins (HD5 and HD6) were found in TI biopsies of children with ileal CD (L1+L3) compared to patients with colonic disease (L2) and healthy controls. In contrast, we found significantly higher levels of alpha-defensins in the TI of children with UC compared to CD and controls. Reduced expression of Tcf-4 was observed exclusively in the duodenum and TI of CD patients with L1+L3 phenotype. We demonstrate significantly increased expression of HD5 and HD6 in the inflamed colon of IBD children (UC and CD) attributable to the presence of metaplastic Paneth cells.

CONCLUSIONS

In this study no difference in alpha-defensin expression was found in the TI of CD children and controls. However, significant reduction of Tcf-4 in L1+L3 phenotype suggests that a possibly impaired PC differentiation may lead to altered HD5 and HD6 expression at some stage of disease. Additionally, substantially increased expression of alpha-defensins in the inflamed colonic mucosa of children with IBD raises the question for their potential involvement in modulating inflammation in these patients.

Fructose malabsorption in children with recurrent abdominal pain: positive effects of dietary treatment

OBJECTIVE

The objective of this study was to analyze the effect of a fructose-restricted diet in otherwise healthy children with abdominal pain and pathologic fructose hydrogen breath test.

SUBJECTS AND METHODS

75 children (aging 3-14 years) with recurrent abdominal pain without gastrointestinal disease and fructose malabsorption followed a fructose restricted diet for 4 weeks.

RESULTS

A median decline of weekly pain frequency from 4 (mean 3.64+1.6) before diet to 1 (mean 1.46+1.4; p<0.001) under fructose restriction was documented. The intensity of pain decreased from median 6 (mean 5.83+2.0) before intervention to median 3 (mean 3.4+2.5; p<0.001) with diet. Several additional life quality-influencing parameters such as daily stool frequency, nausea, problems to fall asleep, missed school days also improved significantly.

CONCLUSIONS

Our study provides evidence that dietary fructose restriction represents a useful approach to address recurrent abdominal symptoms in children with fructose malabsorption.

Incidence of intussusception in early infancy: a capture-recapture estimate for Germany

BACKGROUND

Rotavirus (RV) vaccination with the first generation vaccine (Rotashield) has been associated with intussusception (IS). Reliable age specific baseline incidence data for children ≤6 months of age in particular is fundamental for further post marketing monitoring of potential effects of recently introduced new RV vaccines.

METHODS

IS incidence was estimated by a 2-source capture-recapture calculation (CRC) based on ESPED (German Paediatric Surveillance Unit) reports and on hospital discharge records for 2006 and 2007. ESPED as well as hospital records were validated according to the Brighton Collaboration's Group definition for definite IS.

PATIENTS

Children that have been treated for IS in a hospital in one of two states of Germany (North-Rhine Westphalia and Bavaria).

RESULTS

The annual IS incidence for infants <1 year in Germany calculated with the CRC estimate in Germany was 61.7/100 000 (95% CI: 54.5-70.1). However, the incidence appeared to vary by month of age over a range of 19.2/100 000 cases (95% CI: 12.5-30.4) in the first 3 months of life to 98.5/100 000 cases (95% CI: 80.9-120.6) during the 6 (th) to 8 (th) month. The male to female ratio for infants was 1.7:1 (95%CI: 1.6-1.8).

CONCLUSION

The average incidence estimate for IS in infants (< 1 year) confirms previous estimates in Germany and Switzerland. However, age specific baseline incidence estimates for IS substantially vary during the first year of life. This has to be taken into account when analysing episodes of IS potentially associated with RV vaccination.

Terminally differentiated CD8 cells in HIV-infected children: HIV-GAG/POL specificity and IFN-γ production

BACKGROUND

CD8 cells are key to antiviral immunity and can be divided by phenotype into early (CD28+ CD27+), intermediate (CD28-CD27+) and terminally differentiated subsets (CD28- CD27-). Despite effective HAART there is an unexplained expansion of CD8+CD28-CD27-T cells in HIV-infected children. The cytokine production and specificity of this terminally differentiated CD8 T cell subset in chronic virus infection is unclear. PATIENTS, METHODS & RESULTS: In a cohort of 26 HIV-infected children the cytokine production of terminally differentiated CD8 cells was analyzed by intracellular staining and FACS analysis and was compared to children with chronic hepatitis B infection and to healthy children. The specificity of CD8 subsets was analyzed by staining with Gag/Pol tetramers in a cohort of 13 patients. We show that an increased production of interferon-γ in terminally and early/intermediate differentiated CD8 cell subsets after stimulation is specific for HIV-infection. The expanded population of terminally differentiated CD8+CD28-CD27- T cells does include HIV Gag/Pol specific T cells in adults but not in children.

CONCLUSION

The expansion of terminally differentiated CD8 cells might be important for immunomodulation but in children it does not appear to play a role in HIV Gag and Pol specific immunity.

Memory effect in Dy0.5Sr0.5MnO3 single crystals

We have performed a series of magnetic aging experiments on single crystals of Dy(0.5)Sr(0.5)MnO(3). The results demonstrate striking memory and chaos-like effects in this insulating half-doped perovskite manganite and suggest the existence of strong magnetic relaxation mechanisms of a clustered magnetic state. The spin-glass-like state established below a temperature T(sg)≈ 34 K originates from quenched disorder arising due to the ionic-radii mismatch at the rare earth site. However, deviations from the typical behavior seen in canonical spin glass materials are observed which indicate that the glassy magnetic properties are due to cooperative and frustrated dynamics in a heterogeneous or clustered magnetic state. In particular, the microscopic spin flip time obtained from dynamical scaling near the spin glass freezing temperature is four orders of magnitude larger than microscopic times found in atomic spin glasses. The magnetic viscosity deduced from the time dependence of the zero-field-cooled magnetization exhibits a peak at a temperature T < T(sg) and displays a marked dependence on waiting time in zero field.