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Erika Cecon Anna Ivanova Marine Luka Florence Gbahou Anne Friederich Jean‐Luc Guillaume Patrick Keller Klaus Knoch Raise Ahmad Philippe Delagrange Michele Solimena Ralf Jockers 《Journal of pineal research》2019,66(2)
Melatonin receptors play important roles in the regulation of circadian and seasonal rhythms, sleep, retinal functions, the immune system, depression, and type 2 diabetes development. Melatonin receptors are approved drug targets for insomnia, non‐24‐hour sleep‐wake disorders, and major depressive disorders. In mammals, two melatonin receptors (MTRs) exist, MT1 and MT2, belonging to the G protein‐coupled receptor (GPCR) superfamily. Similar to most other GPCRs, reliable antibodies recognizing melatonin receptors proved to be difficult to obtain. Here, we describe the development of the first monoclonal antibodies (mABs) for mouse MT1 and MT2. Purified antibodies were extensively characterized for specific reactivity with mouse, rat, and human MT1 and MT2 by Western blot, immunoprecipitation, immunofluorescence, and proximity ligation assay. Several mABs were specific for either mouse MT1 or MT2. None of the mABs cross‐reacted with rat MTRs, and some were able to react with human MTRs. The specificity of the selected mABs was validated by immunofluorescence microscopy in three established locations (retina, suprachiasmatic nuclei, pituitary gland) for MTR expression in mice using MTR‐KO mice as control. MT2 expression was not detected in mouse insulinoma MIN6 cells or pancreatic beta‐cells. Collectively, we report the first monoclonal antibodies recognizing recombinant and native mouse melatonin receptors that will be valuable tools for future studies. 相似文献
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Prevalence of H pylori associated 'high risk gastritis' for development of gastric cancer in patients with normal endoscopic findings 总被引:1,自引:0,他引:1
Andreas Leodolter Matthias P Ebert Ulrich Peitz Kathlen Wolle Stefan Kahl Peter Malfertheiner 《World journal of gastroenterology : WJG》2006,(34)
INTRODUCTION H pylori infection is an established risk factor for development of gastric cancer[1,2]. According to the model of carcinogenesis of the intestinal type adenocarcinoma proposed by Correa, the multi-step development starts from the condition o… 相似文献
5.
Christoph Mulert Georg Juckel Michael Brunnmeier Susanne Karch Gregor Leicht Roland Mergl Hans-Jürgen M?ller Ulrich Hegerl Oliver Pogarell 《Clinical EEG and neuroscience》2007,38(2):78-81
During the last 10 years the knowledge about rostral anterior cingulate cortex (ACC) activity in major depression has substantially increased. Several groups have independently described a relationship between resting activity in this area and response to antidepressant treatment. We have recently confirmed a relationship between resting activity of rostral ACC activity and response in a group of 20 patients with major depression using resting theta activity. In this earlier study regions of interest (ROI) were defined in order to establish regional specificity. Differences between responders and nonresponders were only found in the ACC-ROI, but not in the posterior cingulate region. We have now reanalyzed our data using a whole brain voxelwise approach, in order not to miss any other relevant functional differences. In addition to major differences between responders and nonresponders in the rostral ACC, we have identified a nearby region in the midline orbito-frontal region. 相似文献
6.
Robert A. Mischkowski Max J. Zinser Alexander C. Kübler Barbara Krug Ulrich Seifert Joachim E. Zller 《Journal of cranio-maxillo-facial surgery》2006,34(8):478-483
BACKGROUND: An augmented reality tool for computer assisted surgery named X-Scope allows visual tracking of real anatomical structures in superposition with volume rendered CT or MRI scans and thus can be used for navigated translocation of bony segments. METHODS: In a feasibility study X-Scope was used in orthognathic surgery to control the translocation of the maxilla after Le Fort I osteotomy within a bimaxillary procedure. The situation achieved was compared with the pre-operative situation by means of cephalometric analysis on lateral and frontal cephalograms. RESULTS: The technique was successfully utilized in 5 patients. Maxillary positioning using X-Scope was accomplished accurately within a range of 1mm. The tool was used in all cases in addition to the usual intra-operative splints. A stand-alone application without conventional control does not yet seem reasonable. CONCLUSION: Augmented reality tools like X-Scope may be helpful for controlling maxillary translocation in orthognathic surgery. The application to other interventions in cranio-maxillofacial surgery such as Le Fort III osteotomy, fronto-orbital advancement, and cranial vault reshaping or repair may also be considered. 相似文献
7.
S. Maier A. Kleinsasser C. Keller G. Kühbacher A. Löckinger 《Paediatric anaesthesia》2002,12(9):826-826
Introduction QT interval prolongation may cause the potentially lethal tachyarrhythmia torsades de pointes ( 1 ). The cause of the QT interval prolongation may be a congenital mutation in genes encoding cardiac potassium and sodium channels ( 2 ) or be acquired following drug administration ( 3 ) or metabolic disorders ( 4 ). Among a few other drugs volatile anaesthetics prolong the QT interval. During the last few years sevoflurane has become the most used volatile anaesthetic for the induction of anaesthesia in infants.
Methods This investigation, on infants aged from 1 to 6 months, was approved by the institutional ethic committee. Thirty-six otherwise healthy infants due to elective surgery were included in our study The patients were randomly assigned to one of two treatment groups. Group S ( n = 24) was anaesthetised with sevoflurane, Group H was anaesthetised with halothane. ECG recordings were taken before the anaesthesia onset, 15 min after the first contact with the volatile anaesthetic and 60 min after the ending of the volatile gas exposition. QTc interval was calculated using the Bazett's formula ( 5 ).
Results QTc interval was significantly ( P < 0.0002) (Table 1) lengthened 15 min after anaesthesia induction with sevoflurane as well as 60 min ( P < 0.01) after the ending of the gas exposition without any difference in age and gender. The QTc interval in patients anaesthetised with halothane did not show any significant change.
Methods This investigation, on infants aged from 1 to 6 months, was approved by the institutional ethic committee. Thirty-six otherwise healthy infants due to elective surgery were included in our study The patients were randomly assigned to one of two treatment groups. Group S ( n = 24) was anaesthetised with sevoflurane, Group H was anaesthetised with halothane. ECG recordings were taken before the anaesthesia onset, 15 min after the first contact with the volatile anaesthetic and 60 min after the ending of the volatile gas exposition. QTc interval was calculated using the Bazett's formula ( 5 ).
Results QTc interval was significantly ( P < 0.0002) (Table 1) lengthened 15 min after anaesthesia induction with sevoflurane as well as 60 min ( P < 0.01) after the ending of the gas exposition without any difference in age and gender. The QTc interval in patients anaesthetised with halothane did not show any significant change.
Table 1 相似文献
8.
Volkmar Heppert Ulrich Glatzel Thomas Schmickal Andreas Wentzensen 《Trauma und Berufskrankheit》2002,4(4):431-439
External fixation is an apparently simple and therefore highly fascinating method for the stabilization of fractures.Minimally invasive incisions guarantee that regional soft tissue perfusion is conserved after trauma,which makes it the best procedure for stabilization of fractures combined with severe soft tissue damage.However, modern trauma surgery is subject to cyclical trends in the same way as fashion is; noninternal devices are currently barely tolerated.The literature suggests that specialists are virtually competing to see who can stabilize fractures with the most severe soft tissue damage by internal procedures – with the best results, of course. It seems, then, that times are hard for external fixation, but we still believe that for fractures with severe soft tissue damage external fixation still brings a lot of benefit to the patient. 相似文献
9.
Till Neumann Birgit Ross Ulrich R. Hengge Guido Gerken Raimund Erbel 《Medizinische Klinik》2002,117(3):659-665
Zusammenfassung. Die Infektion mit dem humanen Immundefizienzvirus (HIV) betrifft nicht nur das Immunsystem des menschlichen Organismus, sondern schließt vielmehr eine Reihe weiterer Organsysteme mit ein. Es wird angenommen, dass bei 5-15% der HIV-positiven Patienten kardiale Manifestationen auftreten. Zu den häufigsten HIV-assoziierten kardialen Manifestationen gehören der Perikarderguss und die chronisch aktive, fokale oder diffuse Myokarditis. Endokardiale Manifestationen bei HIV-positiven Patienten treten in Form der infektiösen Endokarditis und der nichtbakteriellen thrombotischen Endokarditis auf. In der Regel weisen HIV-assoziierte kardiale Manifestationen einen langsam progredienten Krankheitsverlauf auf. Komplikationen sind Folge eines langfristig unentdeckten Fortschreitens der Erkrankung, aber auch schnell progredienter Verlaufsformen. Aufgrund der Vielzahl HIV-assoziierter kardialer Manifestationen und deren möglicher Komplikationen ist daher neben der Früherkennung ein effektives diagnostisches und therapeutisches Vorgehen erforderlich. Seit Einführung der Proteaseinhibitoren in den 90er Jahren und der Anwendung der hochaktiven antiretroviralen Kombinationstherapie (HAART) konnten sowohl Mortalität als auch Morbidität der HIV-Infektion deutlich gesenkt werden. Die Auswirkungen der HAART auf das kardiovaskuläre System sind bisher nur in Ansätzen bekannt. Als Nebenwirkungen wurden metabolische Veränderungen in Form von Hyperlipoproteinämie und Insulinresistenz bei einer Vielzahl HIV-positiver Patienten beobachtet. Es kann davon ausgegangen werden, dass durch den Anstieg der kardiovaskulären Risikofaktoren unter der HAART in den nächsten Jahren eine erhöhte Rate kardialer Erkrankungen bei HIV-positiven Patienten auftreten wird. In dem vorliegenden Übersichtsartikel wird ein Überblick über die häufigsten kardialen Erkrankungen bei HIV-Infektionen gegeben. Zusätzlich werden Vorschläge zu Diagnostik und Therapie unterbreitet und eine Einschätzung über Veränderungen der HIV-assoziierten kardialen Manifestationen nach Einführung der HAART vorgenommen. Abstract. The human immunodeficiency virus (HIV) does not only affect the immune system. Other organs including the cardiovascular system are influenced by the HIV as well. Most common HIV-associated cardiac manifestations are pericardial effusion and chronic active, focal or diffuse myocarditis. In addition to peri- and myocardial disease, endocardiac manifestations occur as infective endocarditis and nonbacterial thrombotic endocarditis in HIV-infected patients. Although most of the cardiac manifestations associated with HIV-infection exhibit a slow progression, rapid courses may lead to fatal complications. Early screening of HIV-infected patients will identify the potentially fatal complications of HIV disease and permit efficient treatment. The use of highly active antiretroviral therapy (HAART) significantly reduced the mortality and morbidity of HIV-infected patients. However, the impact that HAART will have on the incidence and prevalence of cardiac complications in HIV-infected patients is still unknown. It can be predicted, that the long-term viral infection and the increase of cardiovascular risk factors by HAART will probably lead to an increased prevalence of HIV-infected individuals with cardiac complications in the next decade. The present review describes the most frequent HIV-associated cardiac manifestations including diagnostic and therapeutic perspectives. 相似文献
10.
R Jaeschke G H Guyatt J Singer J Keller M T Newhouse 《Canadian Medical Association journal》1991,144(1):35-39
OBJECTIVE: To examine the mechanisms through which two bronchodilators (theophylline and salbutamol) influence dyspnea during daily activities. METHODS: Twenty-four patients with chronic airflow limitation participated in a multiple crossover, randomized, placebo-controlled trial. The effect of theophylline and salbutamol, alone or combined, on pulmonary function and dyspnea during daily activities was examined. Correlations of changes in forced expiratory volume in 1 second (FEV1) and maximum expiratory pressures (MIPs) (independent variables) and changes in dyspnea score during daily activities (dependent variable) were also examined. RESULTS: The two drugs proved to be beneficial the effects in general were additive rather than synergistic. The drugs improved the FEV1; theophylline significantly improved the MIPs. The correlation between the changes in FEV1 and those in dyspnea score, after adjustment for the changes in MIPs, was 0.55 (p less than 0.001). The correlation between the changes in MIPs and those in dyspnea score, after adjustment for the changes in FEV1, was 0.39 (p less than 0.001). CONCLUSIONS: Changes in airway calibre and in respiratory muscle strength play an independent and important role in dyspnea during daily activities in patients with chronic airflow limitation. Changes in airway calibre may be of greater importance. 相似文献