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1.
Thorsten Grund Konrad Lehmann Nathalie Bock Aribert Rothenberger Gertraud Teuchert-Noodt 《Behavioral and brain functions : BBF》2006,2(1):2-14
Methylphenidate (MPH) is the most commonly used drug to treat attention deficit/hyperactivity disorder (ADHD) in children
effectively and safely. In spite of its widespread application throughout one of the most plastic and sensitive phases of
brain development, very little is known to date about its long-term effects on brain structure and function. Hence, this short
review updates the influence of MPH on brain development, since recent human and animal studies suggest that MPH alters the
dopaminergic system with long-term effects beyond the termination of treatment. 相似文献
2.
Dr. med. Thorsten Schäfer Heike Vogelsang 《Somnologie - Schlafforschung und Schlafmedizin》2002,6(2):79-84
Summary Question of the study Nasal continuous positive airway pressure (CPAP) prevents collapse of the upper airway during sleep in patients with obstructive sleep apnea provided that a positive transmural pressure can be maintained during inspiration. We examined pressure-flow characteristics in seven CPAP and bilevel devices during spontaneous breathing.
Methods The CPAP devices were set to a pressure level of 9.8 hPa (10 cm H2 O) and adapted to a pneumotachograph using a standard CPAP hose and an outlet valve. We continuously measured flow, volume and pressure during resting ventilation and increasing voluntary hyperventilation and analysed the dependence of the variables on a breath-to-breath basis.
Results Mean CPAP pressures differed between the devices (9.9 – 10.6 hPa) despite the same settings. In all machines pressure fell during inspiration to 8.4 – 9.8 hPa and increased during expiration to 11.1 – 11.7 hPa. This effect increased with higher flow rates. Maximum expiratory pressures rose to 12 – 19 hPa at peak flow rates of 2 l/s, mean expiratory pressures to 9.5 – 16 hPa. Inspiratory pressures dropped to 8.5 – 4.5 hPa (minimum) and 10.5 – 6.0 (mean). Bilevel devices showed a higher stability than CPAP devices. Pressure swings during the respiratory cycle increased the additional work of breathing.
Conclusions Due to differences in mean and effective CPAP levels CPAP devices are not simply exchangeable but should be individually adapted. Patients with higher minute ventilation might benefit from more stable CPAP machines. The impact on patients' compliance remains to be evaluated. 相似文献
Methods The CPAP devices were set to a pressure level of 9.8 hPa (10 cm H
Results Mean CPAP pressures differed between the devices (9.9 – 10.6 hPa) despite the same settings. In all machines pressure fell during inspiration to 8.4 – 9.8 hPa and increased during expiration to 11.1 – 11.7 hPa. This effect increased with higher flow rates. Maximum expiratory pressures rose to 12 – 19 hPa at peak flow rates of 2 l/s, mean expiratory pressures to 9.5 – 16 hPa. Inspiratory pressures dropped to 8.5 – 4.5 hPa (minimum) and 10.5 – 6.0 (mean). Bilevel devices showed a higher stability than CPAP devices. Pressure swings during the respiratory cycle increased the additional work of breathing.
Conclusions Due to differences in mean and effective CPAP levels CPAP devices are not simply exchangeable but should be individually adapted. Patients with higher minute ventilation might benefit from more stable CPAP machines. The impact on patients' compliance remains to be evaluated. 相似文献
3.
Thorsten Gerstner Deike Buesing Elke Longin Claudia Bendl Dieter Wenzel Brigitte Scheid Gisela Goetze Alfons Macke Gerhard Lippert Wolfgang Klostermann Geert Mayer Regine Augspach-Hofmann Sabine Fitzek Carl-Albrecht Haensch Markus Reuland Stephan A Koenig 《Seizure》2006,15(6):443-448
Valproic acid (VPA) is a broad-spectrum antiepileptic drug and is usually well-tolerated. Rare serious complications may occur in some patients, including haemorrhagic pancreatitis, bone marrow suppression, VPA-induced hepatotoxicity and VPA-induced encephalopathy. The typical signs of VPA-induced encephalopathy are impaired consciousness, sometimes marked EEG background slowing, increased seizure frequency, with or without hyperammonemia. There is still no proof of causative effect of VPA in patients with encephalopathy, but only of an association with an assumed causal relation. We report 19 patients with VPA-associated encephalopathy in Germany from the years 1994 to 2003, none of whom had been published previously. 相似文献
4.
Inhaled iloprost to control residual pulmonary hypertension following pulmonary endarterectomy 总被引:4,自引:0,他引:4
Thorsten Kramm Balthasar Eberle Stefan Guth Eckhard Mayer 《European journal of cardio-thoracic surgery》2005,28(6):882-888
Objective: Pulmonary endarterectomy (PEA) is the standard therapy for patients with chronic thromboembolic pulmonary hypertension (CTEPH). In the immediate postoperative period, persistent pulmonary hypertension increases the risk of acute respiratory or right heart failure. In pulmonary arterial hypertension, prostanoid inhalation has been found to improve pulmonary hemodynamics, right ventricular function, gas exchange, and clinical outcome. We report the results of a double-blinded randomized trial with the aerosolized prostacyclin analogue iloprost in patients with residual pulmonary hypertension after PEA. Methods: Twenty-two patients (age, 55 ± 13 years; 8 females; propofol- and sufentanil-based anesthesia; pressure-controlled mechanical ventilation) were randomized to receive either a single dose of 25 μg aerosolized iloprost (iloprost group; n = 11) or normal saline (placebo group; n = 11) immediately after postoperative ICU admission. Primary endpoints were changes in gas exchange, pulmonary and systemic hemodynamics, and clinical outcome. Results: Iloprost significantly enhanced cardiac index (CI) and reduced mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance [PVR (dyn s cm−5)] in contrast to placebo. Placebo: pre-inhalation 413 ± 195 versus post-inhalation 404 ± 196 at 30 min (p = 0.051), 415 ± 189 at 90 min (p = 0.929). Iloprost: pre-inhalation 503 ± 238 versus post-inhalation 328 ± 215 at 30 min (p = 0.001), 353 ± 156 at 90 min (p = 0.003). Blood oxygenation remained unchanged. Conclusion: In addition to the effect of PEA, iloprost reduces residual postoperative pulmonary hypertension, decreases right ventricular afterload and may facilitate the early postoperative management after PEA. 相似文献
5.
6.
Thorsten Sch?fer 《Infection》1992,20(6):312-312
Information
1992 science award of the Paul-Ehrlich-Gesellschaft für Chemotherapie e.V. 相似文献7.
Gropp E Shanabrough M Borok E Xu AW Janoschek R Buch T Plum L Balthasar N Hampel B Waisman A Barsh GS Horvath TL Brüning JC 《Nature neuroscience》2005,8(10):1289-1291
Multiple hormones controlling energy homeostasis regulate the expression of neuropeptide Y (NPY) and agouti-related peptide (AgRP) in the arcuate nucleus of the hypothalamus. Nevertheless, inactivation of the genes encoding NPY and/or AgRP has no impact on food intake in mice. Here we demonstrate that induced selective ablation of AgRP-expressing neurons in adult mice results in acute reduction of feeding, demonstrating direct evidence for a critical role of these neurons in the regulation of energy homeostasis. 相似文献
8.
9.
Multilocus haplotype analyses reveal association between 5 novel IL-15 polymorphisms and asthma 总被引:5,自引:0,他引:5
Kurz T Strauch K Dietrich H Braun S Hierl S Jerkic SP Wienker TF Deichmann KA Heinzmann A 《The Journal of allergy and clinical immunology》2004,113(5):896-901
BACKGROUND: IL-15 is a T(H)1-related cytokine that is involved in the inflammatory response in various infectious and autoimmune diseases. IL-15 has recently been shown to be upregulated in T-cell-mediated inflammatory disorders. The observations suggest a potential role for this cytokine in a variety of pathologic conditions, including T(H)1-mediated and T(H)2-mediated inflammatory diseases. OBJECTIVE: In this study, we searched for single nucleotide polymorphisms in the whole IL-15 gene and investigated their association with inflammatory and/or atopic phenotypes. METHODS: The screening for single nucleotide polymorphisms was performed by single-strand conformation polymorphism analysis. Genotyping of the identified polymorphisms was performed by restriction fragment length polymorphism. Genotypic association analysis used the Armitage trend test. Haplotype frequency estimation and subsequent testing for differences between cases and controls were performed by using the programs FASTEHPLUS and FAMHAP. RESULTS: We identified 5 novel noncoding nucleotide sequence variants, all of which were typed in our asthmatic, our atopic, and our control population. According to the Armitage trend test, none of the 5 polymorphisms is associated with the phenotype bronchial asthma or atopy. However, multilocus haplotype analysis based on simulations to find out whether the haplotype frequencies differed between cases and controls by using the program FAMHAP yielded a P value of 6.1 x 10(-5) in the asthmatic versus the control population, which is highly significant. Furthermore, we obtained a nominally significant result of P=.0232 for the atopic versus the control population by using FAMHAP. CONCLUSION: These results strongly underscore previous findings that suggest a potential role of this cytokine in allergic diseases. 相似文献
10.
Lichtenberg A Dumlu G Walles T Maringka M Ringes-Lichtenberg S Ruhparwar A Mertsching H Haverich A 《Biomaterials》2005,26(5):555-562
Investigation of cell abilities to growth, proliferation and (de)-differentiation in a three-dimensional distribution is an important issue in biotechnological research. Here, we report the development of a new bioreactor for three-dimensional cell culture, which allows for co-cultivation of various cell types with different culture conditions in spatial separation. Preliminary results of neonatal rat cardiomyocyte cultivation are shown. Isolated neonatal rat cardiomyocytes were cultured in spatial separated bioreactor compartments in recirculating medium on a biodegradable fibrin matrix for 2 weeks. Glucose, lactate, and lactate dehydrogenase (LDH), pO2, pCO2, and pH levels were monitored in the recirculated medium, daily. Morphological characterization of matrix and cells was assessed by hematoxylin and eosin staining, and MF-20 co-immunostaining with 4',6-diamidino-2-phenylindole (DAPI). Cell viability was determined by LIVE/DEAD staining before cultivation and on day 3, 7, and 14. The optimized seeding density in the matrix was 2.0 x 10(7) cells retaining cellular proportions over the cell culture period. The bioreactor allows the maintenance of physiologic culture conditions with aerobic cell metabolism (low release of lactate, LDH), a high oxygen tension (pO2-183.7 +/- 18.4 mmHg) and physiological pH values (7.4 +/- 0.02) and a constant level of pCO2 (43.1 +/- 2.9) throughout the experimental course. The cell viability was sufficient after 2 weeks with 82 +/- 6.7% living cells. No significant differences were found between spatial separated bioreactor compartments. Our novel multifunctional bioreactor allows for a three-dimensional culture of cells with spatial separation of the co-cultured cell groups. In preliminary experiments, it provided favorable conditions for the three-dimensional cultivation of cardiomyocytes. 相似文献