Reproducibility of food atopy patch tests over time in the general child population

Background  The atopy patch test (APT) is no longer an experimental method; it is increasingly being used as a standard diagnostic tool for the characterization of patients with aeroallergen- and food-triggered disorders. Some technical aspects of this test still remain to be answered. We aimed to study the reproducibility of this test over time in the general child population.
Methods  In a general population of 118 children, we investigated the reproducibility of duplicate APTs with four food allergens in their native form, which were repeated at set intervals from the first test: 7 days (group 1), 14 days (group 2), and 21 days (group 3).
Results  We observed very poor reproducibility on both sides of the back in all three studied subgroups. The reproducibility rates and Cohen's κ values did not improve when we did not consider the side of the back. There were no differences in the prevalence of atopy between the subjects with reproducible and nonreproducible APT results. All three groups studied showed no difference in the prevalence rates of atopy. There was no relationship between APT and skin prick test positivity for the same allergen. Questionnaire-derived data about previous food-related reactions did not help in the evaluation of the doubtful nonreproducible APT results with food allergens.
Conclusions  Our results show that the reproducibility of food APTs is poor and unsatisfactory over time, and there is an urgent need for the development of optimal, stable, and good-quality APT testing substances.     

Polymerization in inverse microemulsions, 4 locus of initiation by ammonium peroxodisulfate and 2,2′-azoisobutyronitrile

The locus of the initiation using the water-soluble radical initiator ammonium peroxodisulfate (APS) and/or the partially water-soluble radical initiator 2,2′-azoisobutyronitrile (AIBN) in the inverse microemulsion system toluene/water (mass ratio 10:1) was studied. The homopolymerization and/or copolymerization of the water-soluble monomer acrylamide (AAM) with the oilsoluble methyl methacrylate (MMA) was investigated. It was found that the locus of initiation by APS in the given system is the water micropool, and the locus of initiation by AIBN is the interlayer between the water micropool and the toluene macrophase.     

Prognostic significance of del(20q) in patients with hematological malignancies

Deletions of the long arm of chromosome 20 represent a common chromosomal abnormality associated with myeloid malignancies, in particular with myeloproliferative disorders (MPD), myelodysplastic syndromes (MDS), and acute myeloid leukemia (AML). Using G-banding cytogenetic techniques, we found clones with del(20q) in 36 patients with hematological malignancies examined in our laboratory during the years 2001–2003: in 23 patients as a sole cytogenetic aberration and in 13 patients together with other chromosomal changes. Fluorescence in situ hybridization (FISH) with a probe specific for the 20q12 region was used in all cases to confirm the presence of the clone with deletion. For patients with additional or complex chromosomal rearrangements, multicolor FISH (M-FISH) analysis was performed. Statistical evaluation of the prognostic impact of sex, age, diagnosis, and karyotype was performed. The survival time correlated with the type of chromosomal aberration; no significant differences in survival were found for sex, age, and diagnosis.     

Quantification of HIV-1 p24 by a highly improved ELISA: an alternative to HIV-1 RNA based treatment monitoring in patients from Abidjan, C?te d'Ivoire.

BACKGROUND: Quantification of HIV-1 RNA remains difficult to implement in Africa. Simple and inexpensive tests for antiretroviral treatment (ART) monitoring are needed. OBJECTIVE: To evaluate an HIV-1 p24 ELISA, which combines efficient virus disruption, heat-denaturation and signal amplification, in a West African setting. STUDY DESIGN: Eighty-six HIV-1 infected patients from Abidjan, C?te d'Ivoire, were tested for p24, HIV-1 RNA, and CD4+ count at baseline, and twice within 8 months after ART initiation. RESULTS: All patients responded to ART with a minimal HIV-1 RNA drop of 0.5 log(10) at first follow-up. Forty-one (47.7%) then rebounded >0.5 log(10) or persisted above 1000 copies/mL by week 24. The predicted baseline concentration of p24 corresponding to 100,000 copies/mL of HIV-1 RNA, above which ART is recommended, was 4546 fg/mL (95% confidence interval 3148-6566). A prediction model of virologic failure, occurring after an initial response to ART, correctly classified 84% of patients using baseline p24, p24 change on therapy, and achievement of undetectable p24 as explanatory variables. The model and further bootstrap evaluation suggested a good ability to discriminate between sustained or failing virologic response to ART. CONCLUSION: HIV-1 p24 and RNA based-ART monitoring in a low-resource country dominated by HIV-1 CRF02 AG appeared comparable.     

HIV-1 p24 antigen is a significant inverse correlate of CD4 T-cell change in patients with suppressed viremia under long-term antiretroviral therapy

An HIV-1 p24 antigen test involving signal amplification-boosted ELISA of heat-denatured plasma was evaluated prospectively in 55 patients whose viral RNA in plasma had previously been suppressed for at least 6 months under antiretroviral combination therapy. During a median follow-up of 504 days, CD4 counts increased by a median of 62 cells per year. By univariate and multivariate linear regression analysis, the level of p24 antigen as expressed by the absorbance/cutoff ratio was a significant inverse correlate of both the CD4 count in a sample (p =.013) and its annual change in a patient (p <.0001). The p24 antigen retained significance even among 48 individuals whose HIV-1 RNA, apart from occasional blips, remained below 400 copies/mL. Batch-wise retesting of 70 samples from 5 such patients with a further improved procedure showed measurable p24 antigen in all but 1 sample and an inverse correlation with both the CD4 count (p =.0331) and percentage (p <.0001), thus confirming the prospectively generated data. Comparison of p24 antigen and HIV-1 RNA concentrations indicate that the p24 antigen detected in these samples is not associated with viral RNA-containing particles and may originate from other compartments of virus expression.     

Transient expression of keratin 19 is induced in originally negative interfollicular epidermal cells by adhesion of suspended cells

Keratin 19 and nuclear reactivity to an endogenous lectin, galectin-1, represent a potential marker of epidermal stem cells. We detected expression of keratin 19 and nuclear binding sites for galectin-1 in adult cells migrating from the hair follicle, where cells expressing keratin 19 are located in the bulge region. The results were compared with the expression of both markers in cells adhering from suspension prepared from the interfollicular epidermis without keratin-19-positive cells and with nuclear binding sites for galectin-1. The results were compared with data from basal cell carcinomas. All cells were analyzed concerning size, as it is known that cell diameter influences the clonogenic potential of keratinocytes. The major result of this study is the observation of transient expression of keratin 19 and nuclear galectin-1 binding sites in originally negative interfollicular epidermal cells induced by adhesion. These cells were very small in size, similar to basal cells of the interfollicular epidermis or the bulge region of the hair follicle. The influence of the suspension regimen on beta1-integrin expression, cell diameter and growth was also monitored. A population of cells highly positive for beta1 integrin of the same diameter as keratin-19-positive cells insensitive to induction of terminal differentiation by lack of anchorage was characterized. Cells of the same size were also observed in the keratin-19-positive cells of basal cell carcinomas. In conclusion, the expression of poor levels of differentiation induced by cell adhesion is transient. Also, keratin 19 expression should not be exclusively regarded as a marker of stem cell activity.     

Liver response to indomethacin-induced intestinal injury

The aim of our study was to evaluate the impact of impaired barrier function of the small intestine induced by indomethacin on biochemical markers of liver damage (serum levels of alanine aminotransferase, aspartate aminotransferase, bilirubin), and liver functional parameters (serum concentration of albumin, liver DNA synthesis). Indomethacin (Sigma) was administered in 2 injections in a dose of 7.5 mg/kg subcutaneously spaced 24 hours apart, rats were sacrificed 24, 48 or 72 hours after the second dose of indomethacin. Control rats received indomethacin vehicle (5% NaHCO3, pH 7.4, 1.0 ml/kg) in the same manner. Small intestine injury was approved by increased permeability (measured as a lactulose-mannitol index). Significant increase of small intestine DNA synthesis (estimated by incorporation of 3H thymidine) in indomethacin-treated rats 48 (p < 0.01) and 72 (p < 0.05) hours after the second dose of indomethacin documents induction of reparative process. All biochemical markers of liver injury were significantly decreased in indomethacin treated rats in all recorded intervals (p < 0.05). By contraries, serum concentration of albumin, which predicates about liver function, was in indomethacin-treated rats significantly decreased in all intervals (p < 0.01). To explain these contrarious results of indomethacin-induced impaired barrier function of the small intestine on the liver deserves further studies.     

The Effect of Omega-3 Fatty Acids on Thromboxane,Brain-Derived Neurotrophic Factor,Homocysteine, and Vitamin D in Depressive Children and Adolescents: Randomized Controlled Trial

In the DEPOXIN project, we have found that a high ratio of omega-6/omega-3 fatty acids (FA) is associated with worsening of depressive symptoms in children and adolescents with depressive disorder (DD) and that the 12-week omega-3 FA supplementation modulates DD symptoms. Here we present our results of the secondary outcomes: the levels of thromboxane (TXB), brain-derived neurotrophic factor (BDNF), homocysteine (HCy) and vitamin D. Fifty-eight patients were randomized into two arms. One group received a fish oil emulsion enriched with omega-3 FA, and the other received a sunflower oil emulsion containing omega-6 FA, for 12 weeks. Depressive symptoms were evaluated, using the Child’s Depressive Inventory (CDI). The patients with DD had elevated TXB levels and decreased vitamin D levels, as compared to healthy controls. Both CDI and omega-6/omega-3 ratio correlated positively with TXB and negatively with BDNF at baseline. Compared to the omega-6 FA group, the supplementation with omega-3 FA for 12 weeks significantly reduced plasma TXB (p = 0.024) and increased BDNF (p = 0.011) levels. No changes in HCy and vitamin D were observed. Our results demonstrate the possible role of TXB and BDNF in the pathophysiology of DD and the benefits of omega-3 FA supplementation. The study was registered with the ISRCTN registry (ISRCTN81655012).     

Are costs derived from diagnosis-related groups suitable for use in economic evaluations? A comparison across nine European countries in the European Healthcare and Social Cost Database

The European Journal of Health Economics - Economic evaluation of health technologies requires healthcare resources, procedures and services to be valued at their opportunity cost. In practice,...     

Properties of visual evoked potentials to onset of movement on a television screen

In 80 subjects the dependence of movement-onset visual evoked potentials on some measures of stimulation was examined, and these responses were compared with pattern-reversal visual evoked potentials to verify the effectiveness of pattern movement application for visual evoked potential acquisition. Horizontally moving vertical gratings were generated on a television screen. The typical movement-onset reactions were characterized by one marked negative peak only, with a peak time between 140 and 200ms. In all subjects the sufficient stimulus duration for acquisition of movement-onset-related visual evoked potentials was 100ms; in some cases it was only 20ms. Higher velocity (5.6°/s) produced higher amplitudes of movement-onset visual evoked potentials than did the lower velocity (2.8°/s). In 80% of subjects, the more distinct reactions were found in the leads from lateral occipital areas (in 60% from the right hemisphere), with no correlation to handedness of subjects. Unlike pattern-reversal visual evoked potentials, the movement-onset responses tended to be larger to extramacular stimulation (annular target of 5°–9°) than to macular stimulation (circular target of 5° diameter).Abbreviation PREP pattern-reversal visual evoked potentials