Induction of autoimmune diabetes through insulin (but not GAD65) DNA vaccination in nonobese diabetic and in RIP-B7.1 mice

Insulin has been used to modify T-cell autoimmunity in experimental models of type 1 diabetes. In a large clinical trial, the effect of insulin to prevent type 1 diabetes is currently investigated. We here show that insulin can adversely trigger autoimmune diabetes in two mouse models of type 1 diabetes, using intramuscular DNA vaccination for antigen administration. In female nonobese diabetic (NOD) mice, diabetes development was enhanced after preproinsulin (ppIns) DNA treatment, and natural diabetes resistance in male NOD mice was diminished by ppIns DNA vaccination. In contrast, GAD65 DNA conferred partial diabetes protection, and empty DNA plasmid was without effect. In RIP-B7.1 C57BL/6 mice (expressing the T-cell costimulatory molecule B7.1 in pancreatic beta-cells), autoimmune diabetes occurred in 70% of animals after ppIns vaccination, whereas diabetes did not develop spontaneously in RIP-B7.1 mice or after GAD65 or control DNA treatment. Diabetes was characterized by diffuse CD4(+)CD8(+) T-cell infiltration of pancreatic islets and severe insulin deficiency, and ppIns, proinsulin, and insulin DNA were equally effective for disease induction. Our work provides a new model of experimental autoimmune diabetes suitable to study mechanisms and outcomes of insulin-specific T-cell reactivity. In antigen-based prevention of type 1 diabetes, diabetes acceleration should be considered as a potential adverse result.     

Detection of MDM2 alterations in cultured human hepatocytes treated with 17beta-estradiol or 17alpha-ethinylestradiol

BACKGROUND: Preneoplastic and neoplastic lesions of the liver are suspected to arise as a result of estrogen treatment. Here we present the first report on the modulational effects of the steroids 17beta-estradiol (E2) and 17alpha-ethinylestradiol (EE2) on oncogene MDM2 in human hepatocytes. MATERIALS AND METHODS: Collagen-embedded cultures of hepatocytes stimulated with different E2/EE2 concentrations were analyzed by immunocytochemistry, RT-PCR and sequencing for MDM2 protein/mRNA expression, MDM2 mRNA splicing and MDM2 gene mutation. RESULTS: The hepatocytes responded to stimulation with steroid E2/EE2 concentrations from 1-100 nmol/l with the overexpression of MDM2 protein while non-stimulated cells were negative. Stimulation with 1 nmol/l E2 and 10-100 nmol/l EE2 induced MDM2 splicing variants. Hepatocytes treated with 100 nmol/l E2 contained full-length MDM2 mRNA carrying a new type of MDM2 gene mutation. Unstimulated hepatocytes revealed neither mRNA splicing nor alteration of the MDM2 genes. CONCLUSION: The data show that steroid hormones are involved in the induction of MDM2 alterations in benign human hepatocytes. We speculate that some of the alterations may influence MDM2 function, thus possibly favouring genesis of liver changes.     

Wind-dispersed pollen mediates postglacial gene flow among refugia

A long-term genetic legacy of refugial isolation has been postulated and was demonstrated for maternal refugial lineages for numerous plant and animal species. The lineages were assumed to have remained separated from each other for several glacial periods. The conifer Abies alba Miller, silver fir, is an excellent model to test whether pollen-mediated gene flow may eliminate the genetic imprints of Pleistocene refugial isolation. Two DNA markers with contrasting modes of inheritance were applied to 100 populations covering the entire range of silver fir in Europe. The markers exhibited each two highly conserved alleles based on an insertion/deletion of 80 bp in the fourth intron of the mitochondrial nad5 gene and on a synonymous substitution in the chloroplast psbC gene. The geographical distribution of the maternally inherited mitochondrial variation supported the existence of at least two refugia with two recolonizing maternal lineages remaining largely separated throughout the range. The cline of the nad5 allele frequencies was much steeper than the one of the two psbC alleles. The psbC cline was as wide as the whole range of the species. Our results provide striking evidence that even a species with very long generation times and heavy pollen grains was able to establish a highly efficient pollen-mediated gene flow between refugia. Therefore we postulate that an exchange of genetic information between refugia by range-wide paternal introgression is possible in wind-pollinated plant species.     

Thrombogenicity of various endovascular stent types: an in vitro evaluation

PURPOSE: The aim of this study was to evaluate the thrombogenicity of different peripheral stent types in a standardized in vitro model with fresh human whole blood. MATERIALS AND METHODS: Different stents (N = 77; n = 7 of each of 11 types) were implanted in polyvinyl chloride tubing loops and filled with donor blood samples. After 120 minutes of blood circulation, the thrombin-antithrombin III complex (TAT) levels, beta-thromboglobulin (beta-TG) levels, and platelet counts were assessed. RESULTS: After 2 hours, significant differences were seen. TAT values (+/- SD) with the investigated stents were 31 micro g/mL +/- 20 (control, no stent), 328 micro g/mL +/- 206 (Saxx stent, peripheral medium CrNi31 L), 651 micro g/mL +/- 760 (Palmaz Corinthian Stent, 316 L stainless steel, electropolished), 1,609 micro g/mL +/- 1,264 (Palmaz Corinthian Stent, 316 L stainless steel, not electropolished), 810 micro g/mL +/- 578 (Palmaz Schatz long medium stent), 569 micro g/mL +/- 347 (Smart Nitinol stent), 1,037 micro g/mL +/- 577 (Megalink peripheral stent), 543 micro g/mL +/- 487 (peripheral stent, electropolished), 1,674 micro g/mL +/- 2,057 (peripheral stent, not electropolished), 3,128 micro g/mL +/- 1,812 (SelfX Nitinol stent, polished), 5,897 micro g/mL +/- 2,380 (SelfX Nitinol stent, unpolished), and 1,458 micro g/mL +/- 887 (bridge stent). The platelet count (x1,000/ micro L +/- SD) was 218 +/- 35 (control, no stent), 188 +/- 22 (Saxx stent), 187 +/- 20 (Palmaz Corinthian stent, electropolished), 135 +/- 37 (Palmaz Corinthian stent, not electropolished), 170 +/- 24 (Palmaz Schatz stent), 180 +/- 36 (Smart Nitinol stent), 159 +/- 26 (Megalink peripheral stent), 173 +/- 17 (peripheral stent, electropolished), 133 +/- 51 (peripheral stent, not electropolished), 123 +/- 37 (SelfX Nitinol stent, polished), 52 +/- 27 (SelfX Nitinol stent, unpolished), and 130 +/- 31 (bridge stent). CONCLUSION: This standardized study showed a wide range of platelet activation after stent implantation. Electropolishing clearly reduced the thrombogenicity of the stents.     

Sleep complaints: snoring and daytime sleepiness in pregnant and pre-eclamptic women

BACKGROUND AND PURPOSE: To examine whether snoring and sleepiness are linked in pregnancy and pre-eclampsia. PATIENTS AND METHODS: We recruited 167 healthy and 82 pre-eclamptic women in the third trimester of pregnancy and 160 non-pregnant women. Subjects and their partners completed a sleep questionnaire. Height, weight, neck circumferences and blood pressure were recorded for all. RESULTS: Pregnant and pre-eclamptic women were (mean +/-SD) 36+/-3.6 and 36+/-3 weeks pregnant, respectively. Age and height did not differ significantly between groups (P>0.2), but pre-eclamptic women were heavier than pregnant and non-pregnant women and had higher BMI than pregnant women before pregnancy (all P<0.05). Thirty-two percent of control, 55% of pregnant and 85% of pre-eclamptic women snored (P<0.001), but pre-pregnancy snoring rates (pre-eclamptic=36%, healthy pregnant women=27%) were similar to those in non-pregnant women (32%) (P>0.7). Sleepiness was reported by 12% of non-pregnant, 23% of pregnant and 15% of pre-eclamptic women (P<0.04), but non-pregnant women had lower mean Epworth Sleepiness scores than both pregnant and pre-eclamptic groups (P<0.001). Snoring was correlated with (P=0.002), but explained only <2%, of the variance in sleepiness. CONCLUSION: Snoring and sleepiness increased in the third trimester of pregnancy, particularly in patients with pre-eclampsia. However, the study suggests that sleepiness in pregnancy is largely due to factors other than snoring or breathing pauses.     

Assessing the risk of mortality in paediatric cancer patients admitted to the paediatric intensive care unit: a novel risk score?

Intensive front-line protocols have improved survival in children with malignancies; however, intensive multimodal therapy of paediatric malignancies can be associated with a significant risk of serious adverse events. Common risk scores (PRISM, PRISM III, APACHE-II) fail to predict mortality in these patients. A retrospective chart analysis of 32 paediatric cancer patients admitted to the Paediatric Intensive Care Unit (PICU) at the University Hospital of Saarland between January 2001 and December 2003 for life-threatening complications was performed. The aim of this study was to assess risk factors for short-term outcome (survival vs. non-survival when leaving the PICU) and to develop a risk score to estimate outcome in these patients. Overall survival was good (25 of 32 patients). Mortality rate was significantly related to leukaemia/lymphoma ( P =0.029), to the number of organ failures ( P <0.0001), neutropenia ( P =0.001), septic shock ( P =0.025), mechanical ventilation ( P =0.01) and inotropic support ( P =0.01). Employing multiple logistic regression, the strongest predictor for poor outcome was the number of organ failures ( P <0.05). A risk score (cut-off value: >3 points for non-survival) which included the following risk factors (non-solid tumour, number of organ failures ( n >2), neutropenia, septic shock, mechanical ventilation, and inotropic medication) yielded a sensitivity of 7/7 (95% CI: 4.56–7.00), a specificity of 23/25 (95% CI: 18.49–24.75), a positive predictive value of 23/23 (95% CI: 19.80–23.00), and a negative predictive value of 7/9 (95% CI: 3.60–8.74) for the time of admission to the PICU. Conclusion:Although our risk of mortality score is of prognostic value in assessing short-term outcome in these patients, prospective validation in a larger study cohort is mandatory. Furthermore, it must be emphasised that this risk score must not be used for decision-making in an individual patient.     

Treatment of acute crisis in child and adolescent psychiatry

Crises from the child and adolescent psychiatric point of view must be considered as unique or repeated moments of basic questioning of self-focused and relational perception. Hospitalisation if necessary depends on a well prepared social, legal, physical and cooperative framework. Patients, their family or social environment are in need of clarity, structure, and a professional counterpart willing to engage responsibly within an inpatient or--mostly--outpatient framework. He must adapt his diagnostic or therapeutic action to the patient's experience of fear, loss of orientation and insecurity. Then a crisis may be experienced like a bonding experience. Concerning the capacity of action confronted to psychiatric crisis the authors stress the importance of the scenic understanding, expressed symptoms and the acted-out crisis dynamics more than diagnostic classification. The diagnostic and decisive process of atunement to the patient in crisis is being described. A model for psychodynamic understanding of perception of and action towards crisis is proposed, which allows describing the interference between relational dynamics and intra-psychic conflicts leading to crisis. This can then be used as therapeutical focus for the crisis intervention or a consecutive psychotherapeutic treatment.