Positive or negative fructose breath test results do not predict response to fructose restricted diet in children with recurrent abdominal pain: results from a prospective randomized trial.

OBJECTIVES: To perform a prospective, blinded, randomized interventional trial in patients with recurrent abdominal pain. The primary endpoint was to determine the abdominal pain intensity after 2 weeks of fructose restricted diet. Secondary endpoints were changes of pain frequency and a secondary symptom score (SSS). METHODS: 103 individuals with recurrent abdominal pain for more than 3 months were randomized. 51 patients were allocated to group A (diet) and 52 to group B (no diet). 2 weeks later the patients underwent hydrogen breath test and were assigned to the test positive or negative group to identify patients with fructose malabsorption. RESULTS: 2 weeks after intervention the pain score decreased significantly from a median 5.5 in group A to 4 and did not change significantly in group B (5.3 to 5). In group A both patients with positive and negative breath tests had a significant lower pain score (-2 and -1.75, respectively). Frequency of abdominal pain decreased in both groups but without significant difference, SSS improved only in group A from median 6 to 3.5. Positive breath test was no predicting factor, neither was abdominal pain during the test. CONCLUSIONS: Fructose restricted diet in children and adolescents with recurrent abdominal pain may be of benefit to improve both abdominal pain symptoms and other secondary symptoms. Since a negative breath test result does not exclude a positive response to fructose restriction, the hydrogen breath test does not seem to be the appropriate diagnostic mean to predict the response to the diet.

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.

Generation of cellular immune responses to HCV NS5 protein through in vivo activation of dendritic cells.

Chronic hepatitis C (HCV) infection is a substantial medical problem that leads to progressive liver disease, cirrhosis, and hepatocellular carcinoma (HCC). The aim of this study was to achieve sustained cellular immune responses in vivo to a HCV nonstructural protein using dendritic cell (DC)-based immunization approach. We targeted the HCV NS5 protein to DCs in vivo by injecting microparticles loaded with this antigen. The DC population was expanded in BALB/C mice (H-2(d) ) by hydrodynamic injection of a plasmid pUMVC3-hFLex expressing the secreted portion of the human Fms-like tyrosine kinase receptor-3 ligand (hFlt3). Mice were subsequently injected with microparticles coated with HCV NS5 protein via the tail vein. Cellular immune responses were determined with respect to secretion of INFγ and IL2 by CD4(+) cells and cytotoxic T-lymphocyte (CTL) assays in vitro; inhibition of tumour cell growth was employed for the assessment of CD8(+) generated activity in vivo. We found that Flt3L treatment expanded the DC population in the spleen to 43%, and such cells displayed a striking upregulation of CD86 as well as CD80 and CD40 co-stimulating molecules. Viral antigen-specific T(H) 1 cytokine secretion by splenocytes was generated, and CTL activity against syngeneic NS5 expressing myeloma target cells was observed. In addition, these cells inhibited tumour growth indicating that NS5-specific robust CTL activity was operative in vivo. Thus, the capability of activating DCs in vivo using the methods described is valuable as a therapeutic vaccine strategy for chronic HCV infection.

Clinical features and biochemical data of Caucasian children at diagnosis of autoimmune hepatitis.

OBJECTIVE: Evaluation of systematic epidemiological data regarding clinical characteristics, sex distribution and autoantibody pattern in Caucasian children with autoimmune hepatitis (AIH). STUDY DESIGN: Data of 142 children presenting with AIH (97 girls and 45 boys) have been analysed for their clinical, serological, and histological profile. RESULTS: Clinical findings were jaundice (58%), unspecific weakness (57%), anorexia (47%), abdominal pain (38%) and paleness (26%). One hundred and three children (73%) (68 girls, 35 boys, 1.9:1) had AIH type 1 and 35 patients (25%) (27 girls, 8 boys, 3.4:1) type 2 due to specific autoantibodies. Four children could not be classified. Histology of 122 children revealed active hepatitis in 64 (52%), cirrhosis in 46 (38%), and mild inflammatory activity in 12 individuals (10%). The most prevalent HLA type was B8. CONCLUSION: In our cohort the prevalence of AIH was half as frequent in boys as in girls. Type 1 was the most frequent diagnosis (73%) and was more prevalent in older children. Type 2 was equally age distributed. The clinical presentation of AIH in children was unspecific and type I and type II could only be differentiated by the determination of the specific autoantibodies. Ninety percent of patients presented with high inflammatory activity or liver cirrhosis.

Mutation analysis and association studies of nuclear factor-kappaB1 in sporadic Parkinson's disease patients.

Biochemical and morphological studies revealed that oxidative stress and apoptosis play a role in neurodegeneration in Parkinson's disease (PD). Reactive oxygen species may be directly involved in apoptosis or via upregulation of toxic cytokines, i.e. tumor necrosis factor alpha (TNFalpha). We recently demonstrated that the TNFalpha pathway contributes to the pathogenesis of sporadic PD using a genetic approach. These signalling pathways converge to the transcription factor nuclear factor kappaB (NF-kappaB), which has been found activated in affected neurons in PD. We performed a detailed mutation analysis of the p50 subunit of NF-kappaB (NFKB1 gene) in 96 sporadic PD patients. Previously, positive association was demonstrated in this cohort to chromosome 4q21-23 containing the NFKB1 gene. We identified three base exchanges not affecting the amino acid sequence, which were found at similar frequencies in controls. Our study does not support a genetically definable role of NFKB1 in the pathogenesis of sporadic PD.

Mutation analysis and association studies of the UCHL1 gene in German Parkinson's disease patients.

Recently, an Ile93Met substitution has been identified in the ubiquitin carboxy-terminal hydrolase L1 (UCHL1) gene in a single German PD family with autosomal dominant inheritance. To determine whether mutations in the UCHL1 gene are causative for Parkinson's disease (PD) a detailed mutation analysis was performed in a large sample of German sporadic and familial PD patients. We found no disease-causing mutation in the coding region of the UCHL1 gene. Direct sequencing revealed six intronic polymorphisms in the UCHL1 gene. Analysis of an S18Y polymorphism in exon 3 of the UCHL1 gene in sporadic PD patients and controls showed carriers of allele 2 (tyrosine) significantly less frequent in patients with a reduced risk of 0.57 (CI = 0.36-0.88; p = 0.012, p(c) = 0.047, chi2 = 6.31). Our study shows that sequence variations in the coding region of UCHL1 are a rare event. A protective effect of a certain UCHL1 variant in the pathogenesis of sporadic PD is suggested, underlining the relevance of UCHL1 in neurodegeneration.

PCR/SSCP detects reliably and efficiently DNA sequence variations in large scale screening projects.

A simple and fast method with high reliability is necessary for the identification of mutations, polymorphisms and sequence variants (MPSV) within many genes and many samples, e.g. for clarifying the genetic background of individuals with multifactorial diseases. Here we review our experience with the polymerase chain reaction/single-strand conformation polymorphism (PCR/SSCP) analysis to identify MPSV in a number of genes thought to be involved in the pathogenesis of multifactorial neurological disorders, including autoimmune diseases like multiple sclerosis (MS) and neurodegenerative disorders like Parkinson s disease (PD). The method is based on the property of the DNA that the electrophoretic mobility of single stranded nucleic acids depends not only on their size but also on their sequence. The target sequences were amplified, digested into fragments ranging from 50-240 base pairs (bp), heat-denatured and analysed on native polyacrylamide (PAA) gels of different composition. The analysis of a great number of different PCR products demonstrates that the detection rate of MPSV depends on the fragment lengths, the temperature during electrophoresis and the composition of the gel. In general, the detection of MPSV is neither influenced by their location within the DNA fragment nor by the type of substitution, i.e., transitions or transversions. The standard PCR/SSCP system described here provides high reliability and detection rates. It allows the efficient analysis of a large number of DNA samples and many different genes.