Prospective population-based study of viral lower respiratory tract infections in children under 3 years of age (the PRI.DE study)

Population-based incidence data from Europe on the disease burden of lower respiratory tract infections (LRTI) due to respiratory syncytial viruses (RSV), parainfluenza viruses (PIV) and influenzaviruses (IV) are lacking, especially with respect to the disease burden. In a 2-year prospective multicentre study of children aged <3 years in Germany, we registered population-based cases as outpatients (n=2386), inpatients (n=2924), and nosocomially-acquired (n=141). Nasopharyngeal secretions were tested for viral RNA. The annual incidence for physician visits per 100 children for all LRTI was 28.7, RSV 7.7, PIV 3.8 and IV 1.1. Annual hospitalisation rates per 10⁵ children were for all LRTI 2941, RSV 1117, PIV 261 and IV 123. Annual nosocomial cases per 10⁵ hospital days were for all LRTI 79, RSV 29, PIV 9 and IV 1.5. All five children (0.27%) who died had an underlying disease and four were nosocomially acquired. Conclusion: Hospitalisation rates due to lower respiratory tract infections in healthy children were similar to those reported elsewhere; the rates for outpatient visits were approximately ten times higher.     

Closed suctioning system reduces cross-contamination between bronchial system and gastric juices

In this prospective, randomized study, we evaluated whether a closed suctioning (CS) system (TrachCare) influences crossover contamination between bronchial system and gastric juices when compared with an open suctioning system (OS). The secondary aims were an analysis of the frequency of ventilator-associated pneumonia (VAP) and an analysis of alteration in gas exchange. Antibiograms were performed from tracheal secretions and gastric juice aspirates on Days 1 and 3 of intubation in 24 patients in a medical intensive care unit. Five cross-contaminations were observed in the OS group on Day 3 versus Day 1; the 5 strains shared common genotypes as determined by random amplification of polymorphic DNA. No cross-contaminations were seen in the CS group (P = 0.037). VAP occurred in 5 patients of the OS group but in none of the CS group patients (P = 0.037). Spao(2) decreased significantly in the OS group compared with presuctioning values--the opposite of the CS group. Whereas presuctioning values were comparable between groups, postsuctioning Spao(2) was significantly higher in the CS group. CS significantly reduced cross-contamination between bronchial system and gastric juices and reduced the incidence of VAP when compared with OS. Hypoxic phases can be reduced by the help of CS.     

Relationship between cytokine concentrations (FGF, sICAM-1 and SCF) in serum, follicular fluid and ICSI outcome

OBJECTIVE: The aim of this study was (i) to investigate the existence of fibroblast growth factor (FGF), soluble intracellular adhesion molecule-1 (sICAM-1), and stem cell factor (SCF) in serum and human follicular fluid (FF) of intracytoplasmic sperm injection (ICSI) patients, and (ii) to determine the relationship between these parameters and ICSI outcome. MATERIAL AND METHOD: Seventy-five patients undergoing controlled ovarian hyperstimulation with human menopausal gonadotropin (hMG) after down-regulation with GnRHa were included in this study. The concentrations of FGF, SCF, and sICAM-1 were measured by using commercially available enzyme-linked immunosorbent assay test kits. RESULTS: The FGF, sICAM-1, and SCF concentrations in the serum of women who become pregnant (group I) were 8.5 +/- 1.5 pg/mL, 235.8 +/- 81.1 ng/mL, and 597.7 +/- 139.9 pg/mL, and the corresponding concentrations of women who did not (group II) were 6.4 +/- 3.6 pg/mL, 230.6 +/- 66.5 ng/mL, and 569.6 +/- 91.4 pg/mL respectively. No significant difference was observed between the two investigated groups with regard to the number of hMG ampoules administered for controlled ovarian hyperstimulation, estradiol concentration on the day of human chorionic gonadotropin (hCG) injection, number of retrieved oocytes and fertilization rate. CONCLUSION: The concentration of FGF, sICAM-1, and SCF did not differ significantly between the two groups in serum or in FF. Besides, the ICSI outcome was not related to their concentrations in serum or FF. Therefore, these parameters could not be used as a prognostic factor in ICSI program.     

Anxiolytic-like profile in Wistar, but not Sprague–Dawley rats in the social interaction test

Rationale The social interaction test is a valuable behavioural model for testing anxiolytic drugs in rodents, quantifying the level of social behaviour between pairs of rats.Objective The aim of the present study was to assess the appropriateness of the social interaction test for use with a Sprague–Dawley rat line, because of increasing use of this strain in targeted mutagenesis research.Methods Sprague–Dawley and Wistar rats received either diazepam or mCPP or were exposed to different environmental conditions (lighting, social isolation prior testing, habituation, testing-time). General anxiety-related parameters measured were: duration of active social contact, frequency of active social contact, latency to first contact. Different forms of active social contact were recorded: number of crawls, follows and sniffs. Secondly, aversion-induced hippocampal serotonin release and serotonin content in brain regions were measured.Results In Wistar rats habituation to the test substantially increased the time of social contact, an effect comparable with treatment with diazepam (1 mg/kg), whereas changes in the lighting level had less impact. Latency to the first contact increased under anxiety-reducing conditions, the frequency of contacts did not change consistently. Sprague–Dawley rats behaviour did not change under varying environmental conditions, and treatment with diazepam had only sedating effects at higher doses (5 mg/kg). Anxiogenic doses of mCPP caused reduced social interaction in both strains. Serotonin release and serotonin content were higher in the anxious Wistar rats.Conclusions Different rat strains as well as differing test conditions have a major impact on the outcome of this animal test for anxiety.     

Antidepressant-like effect of nicotinamide adenine dinucleotide in the forced swim test in rats

Nicotinamide adenine dinucleotide (NADH), a cosubstrate for energy transfer in the oxidative phosphorylation, has supposedly beneficial effects on central nervous system (CNS)-related diseases, e.g., shown in an open study with depressive patients. To our knowledge there are no data concerning the efficacy of NADH in animal tests. Acute effects of NADH and the precursor nicotinamide, compared to controls and the antidepressants desipramine and fluoxetine, were examined in the forced swim test (FST) in Wistar rats. NADH, but not nicotinamide, reduced immobility and increased swimming behaviour in the FST, with a minimum effective dose of 5 mg/kg. NADH-induced behavioural profile was similar to fluoxetine, but different from desipramine. Since NADH did not induce hyperlocomotion but even decreased motor activity in the open field test, the antidepressant-like effect cannot be attributed to an increase in motor activity. These data support an antidepressant potential of NADH.     

New peptaibols from Mycogone cervina

From cultures of Mycogone cervina, a mycophilic fungus growing on the fruit bodies of ascomycete Paxina acetabulum, two new peptaibols (cervinin, N-Ac-Leu-Aib-Pro-Aib-Leu-Aib-Pro-Ala-Aib-Pro-Val-red-Leu (1) and the red-Leu O-acetylated derivative 2) were isolated. The structures of 1 and 2 were elucidated by spectroscopic techniques. They exhibited weak antibacterial as well as cytotoxic activities. They are the first secondary metabolites described from M. cervina.     

Anxiety as a predictor of alcohol preference in rats?

Many clinical studies based on retrospective self-reports indicate a relationship between anxiety and increased alcohol consumption or relapse in individuals with alcohol abuse or dependence. However, by these retrospective studies it cannot be definitely concluded whether the alcohol abuse or the anxiety was first. In the present study, alcohol-consuming behaviour was determined in three rat strains showing different anxiety-related behaviour but being not genetically selected for high or low alcohol consumption. The innate anxiety of the three rat strains (Harlan-Fischer, Wistar-BgVV and Wistar-Harlan) was measured by the elevated plus maze test. Thereafter voluntary ethanol intake was measured for 3 months followed by a progressive ratio paradigm, in which the number of responses required to obtain alcohol was successively increased during session. The point at which rats ceased to respond (breaking point) was taken as a measure of their motivation to obtain ethanol. The study revealed that Harlan-Fischer rats showing most anxiety-related behaviour in the elevated plus maze test displayed the lowest ethanol intake [g/kg/d b.w.] and the lowest breaking points in the progressive ratio paradigm. The Wistar-Harlan rats with least anxiety-related behaviour and the Wistar-BgVV rats with medium anxiety-related behaviour drank more alcohol and showed higher breaking points than the Harlan-Fischer rats. Thus, in the present study, a distinct relationship between innate anxiety and alcohol-consuming behaviour in rat strains not genetically selected for high and low ethanol intake could not be shown.     

The antiepileptic drug levetiracetam selectively modifies kindling-induced alterations in gene expression in the temporal lobe of rats

Gene expression profiling by microarrays is a powerful tool for identification of genes that may encode key proteins involved in molecular mechanisms underlying epileptogenesis. Using the Affymetrix oligonucleotide microarray, we have surveyed the expression levels of more than 26,000 genes and expressed sequence tags (ESTs) in the amygdala-kindling model of temporal lobe epilepsy. Furthermore, the effect of the antiepileptic drug levetiracetam (LEV) on kindling-induced alterations of gene expression was studied. Treatment of rats with LEV during kindling acquisition significantly suppressed kindling development. For gene expression profiling, six groups of rats were included in the present study: (i) and (ii) sham-operated rats treated with saline or LEV; (iii) and (iv) electrode-implanted but non-kindled rats treated with saline or LEV; (v) and (vi) kindled rats treated with saline or LEV. Treatment was terminated after 11 or 12 daily amygdala stimulations, when all vehicle-treated rats had reached kindling criterion, i.e. a stage 5 seizure. Twenty-four hours later, the ipsilateral temporal lobe was dissected for mRNA preparation. Six temporal lobe preparations from each group were analysed for differential gene expression. In control (non-kindled) rats, LEV treatment was devoid of any significant effect on gene expression. In saline-treated kindled rats, a large number of genes were observed to display mRNA expression alterations compared with non-kindled rats. LEV treatment induced marked effects on gene expression from kindled rats. Previously described epilepsy-related genes, such as neuropeptide Y (NPY), thyrotropin-releasing hormone (TRH) and glial fibrillary acidic protein (GFAP) were confirmed to be up-regulated by kindling and partially normalized by LEV treatment. Real-time quantitative polymerase chain reaction confirmed NPY, TRH and GFAP expression data from chip experiments. Furthermore, a number of novel genes were identified from the gene chip experiments. A subgroup of these genes demonstrated correlation between expression changes and kindled phenotype measurements. In summary, this study identified many genes with potentially important roles in epileptogenesis and highlighted several important issues in using the gene chip technology for the study of animal models of CNS disorders.