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Mutations in the PINK1 gene cause autosomal recessive familial Parkinson’s disease (PD). The gene encodes a mitochondrial protein kinase that plays an important role in maintaining mitochondrial function and integrity. However, the pathophysiological link between mutation-related bioenergetic deficits and the degenerative process in dopaminergic neurons remains to be elucidated. We performed phosphorous (31P) and proton (1H) 3-T magnetic resonance spectroscopic imaging (MRSI) in 11 members of a German family with hereditary PD due to PINK1 mutations (PARK6) compared to 23 age-matched controls. All family members had prior 18-Fluorodopa (FDOPA) positron emission tomography (PET). The striatal FDOPA uptake was correlated with quantified metabolic brain mapping in MRSI. At group level, the heterozygous PINK1 mutation carriers did not show any MRSI abnormalities relative to controls. In contrast, homozygous individuals with manifest PD had putaminal GPC, PCr, HEP and β-ATP levels well above the 2SD range of controls. Across all subjects, the FDOPA Ki values correlated positively with MI (r = 0.879, p<0.001) and inversely with β-ATP (r = −0.784, p = 0.008) and GPC concentrations (r = −0.651, p = 0.030) in the putamen. Our combined imaging data suggest that the dopaminergic deficit in this family with PD due to PINK1 mutations relates to osmolyte dysregulation, while the delivery of high energy phosphates was preserved. Our results corroborate the hypothesis that PINK1 mutations result in reduced neuronal survival, most likely due to impaired cellular stress resistance.
Temporal predictability is thought to affect stimulus processing by facilitating the allocation of attentional resources. Recent studies have shown that periodicity of a tonal sequence results in a decreased peak latency and a larger amplitude of the P3b compared with temporally random, i.e., aperiodic sequences. We investigated whether this applies also to sequences of linguistic stimuli (syllables), although speech is usually aperiodic. We compared aperiodic syllable sequences with two temporally regular conditions. In one condition, the interval between syllable onset was fixed, whereas in a second condition the interval between the syllables’ perceptual center (p-center) was kept constant. Event-related potentials were assessed in 30 adults who were instructed to detect irregularities in the stimulus sequences. We found larger P3b amplitudes for both temporally predictable conditions as compared to the aperiodic condition and a shorter P3b latency in the p-center condition than in both other conditions. These findings demonstrate that even in acoustically more complex sequences such as syllable streams, temporal predictability facilitates the processing of deviant stimuli. Furthermore, we provide first electrophysiological evidence for the relevance of the p-center concept in linguistic stimulus processing.
Background: Repetitive transcranial magnetic stimulation (rTMS) allows non-invasive stimulation of the human brain. However, no suitable marker has yet been established to monitor the immediate rTMS effects on cortical areas in children.
Objective: TMS-evoked EEG potentials (TEPs) could present a well-suited marker for real-time monitoring. Monitoring is particularly important in children where only few data about rTMS effects and safety are currently available.
Methods: In a single-blind sham-controlled study, twenty-five school-aged children with ADHD received subthreshold 1 Hz-rTMS to the primary motor cortex. The TMS-evoked N100 was measured by 64-channel-EEG pre, during and post rTMS, and compared to sham stimulation as an intraindividual control condition.
Results: TMS-evoked N100 amplitude decreased during 1 Hz-rTMS and, at the group level, reached a stable plateau after approximately 500 pulses. N100 amplitude to supra-threshold single pulses post rTMS confirmed the amplitude reduction in comparison to the pre-rTMS level while sham stimulation had no influence. EEG source analysis indicated that the TMS-evoked N100 change reflected rTMS effects in the stimulated motor cortex. Amplitude changes in TMS-evoked N100 and MEPs (pre versus post 1 Hz-rTMS) correlated significantly, but this correlation was also found for pre versus post sham stimulation.
Conclusion: The TMS-evoked N100 represents a promising candidate marker to monitor rTMS effects on cortical excitability in children with ADHD. TMS-evoked N100 can be employed to monitor real-time effects of TMS for subthreshold intensities. Though TMS-evoked N100 was a more sensitive parameter for rTMS-specific changes than MEPs in our sample, further studies are necessary to demonstrate whether clinical rTMS effects can be predicted from rTMS-induced changes in TMS-evoked N100 amplitude and to clarify the relationship between rTMS-induced changes in TMS-evoked N100 and MEP amplitudes. The TMS-evoked N100 amplitude reduction after 1 Hz-rTMS could either reflect a globally decreased cortical response to the TMS pulse or a specific decrease in inhibition.
Am 26. November 2010 erhoben sich im großen Saal des Internationalen Congress Centrums in Berlin rund 3.000 Psychiaterinnen und Psychiater, um für eine Minute zu schweigen. Was sie zuvor gehört hatten, war zutiefst beeindruckend und blieb für die Anwesenden unvergesslich. Prof. Frank Schneider, der Präsident der deutschen Gesellschaft für Psychiatrie, Psychotherapie und Nervenheilkunde (DGPPN), bat bei den Psychiatrie-Opfern und deren Angehörigen aus der Zeit des Nationalsozialismus in einem Ausmaß um Verzeihung, wie wohl nur wenige deutsche Ärzte zuvor. ...
On 26th November 2010 around 3000 psychiatrists rose up for a minute's silence in the great hall of the International Congress Centrum in Berlin. What they had heard before, was deeply impressive and memorable to the audience. Professor Frank Schneider, president of the German Society for Psychiatry, Psychotherapy and Neurology (DGPPN) asked the psychiatric victims and their relatives of the Nazi era for forgiveness to an extent as only a few German Doctors done before. ...
Background: In macrophages Toll-like receptor 4 (TLR4) is activated in response to lipopolysaccharide (LPS) and induces proinflammatory cytokine expression. Therefore, mechanisms terminating proinflammatory gene expression are important. Autophagy plays a central role in controlling innate immune responses by lysosomal degradation of signaling proteins, thus contributing to the resolution of inflammation. Autophagic proteins like p62 directly interact with molecules involved in the TLR4-signaling pathway, but a correlation with the IRAK E3 ligase and scaffold protein Pellino3 remains obscure. Hence, we are interested in elucidating the function of Pellino3 to prove our hypothesis that it is a key regulator in the TLR4-signaling cascade.
Methods: We used the cecal ligation and puncture (CLP) mouse model causing polymicrobial sepsis to analyze Pellino3 protein and mRNA expression. Furthermore, we induced endotoxemia in RAW264.7 mouse macrophages by LPS treatment to verify in vivo experiments. Lentiviral Pellino3 knockdown in RAW264.7 macrophages was used for cytokine measurements at mRNA level. To analyze potential Pellino3 binding partners in TLR4-signaling by mass spectrometry (MS), we overexpressed FLAG-tagged Pellino3 in RAW264.7 macrophages, treated cells for 3, 6 and 24 hours with LPS and immunoprecipitated Pellino3 via its FLAG-tag. To consider Pellino3 degradation as a result of p62-mediated autophagy, we transiently knocked down p62 by siRNA in RAW264.7 macrophages and also pharmacologically blocked LPS-induced autophagy by Bafilomycin A1.
Results: We demonstrated Pellino3 protein degradation in primary CD11b+ splenocytes after 24 hours following CLP operation and confirmed this in RAW264.7 macrophages after 24-hour LPS stimulation. Knockdown of Pellino3 attenuates proinflammatory cytokines, for example IL-6 mRNA, after 6 hours of LPS. Furthermore, we found by MS and verifying immunoprecipitation experiments that p62 is a Pellino3 binding partner, thus targeting Pellino3 for degradation. In line, both p62 knockdown and Bafilomycin A1 treatment prevent Pellino3 degradation, supporting an autophagic mechanism.
Conclusion: Our observations highlight a regulatory role of Pellino3 on TLR4 signaling. Thus, antagonism of Pellino3 in the hyperinflammatory phase of sepsis may counteract the cytokine storm. Furthermore, stabilization of Pellino3 by inhibition of autophagy in the hypoinflammatory phase of sepsis may improve immunity. In consideration of these two conflictive sepsis phases, modulation of Pellino3 may provide a new strategy for the development of a therapy approach in sepsis.
In der vorliegenden prospektiven randomisierten Studie mit 80 Patienten zur aortokoronaren Venenbypass-Operation hatten wir das Ziel, die traumatischen Effekte durch das partielle Ausklemmen als auch durch den Aortenkonnektor und die dadurch entstehenden partikulären Embolien zu identifizieren. Des Weiteren sollten diese partikulären Embolien von solchen nach dem Öffnen der Aortenklemme unterschieden werden.
Es ist dabei wichtig festzuhalten, dass der erste Filter, welcher das Trauma an der Aorta beim Fertigen der proximalen Anastomose repräsentiert, bei schlagendem Herzen eingesetzt wurde. Der zweite Filter wurde während der extrakorporalen Zirkulation mit HLM eingebracht und nach dem Öffnen der totalen Querklemmung der Aorta entfernt.
Wir konnten die Fertigung der proximalen Anastomose als eine wichtige Quelle für ein solches embolisches Geschehen und die damit verbundenen neurologischen Komplikationen identifizieren.
Dabei spielt die Art der Fertigung der proximalen Anastomose keine Rolle. Wir konnten somit zeigen, dass es keinen Unterschied hinsichtlich der Entstehung partikulärer Embolien zwischen einer konventionellen proximalen Anastomose oder einer mit Hilfe des Symmetry Aorten- Konnektor- Systems gefertigten Anastomose gibt.
Die Anzahl der geborgenen Partikel ist unabhängig von der gewählten Fertigungsart nicht signifikant verschieden. Ebenso konnten wir hinsichtlich der Oberflächengröße der im ersten Filter geborgenen Partikel keinen Unterschied zwischen der automatisierten und konventionellen Fertigung erkennen.
Es konnte somit gezeigt werden, dass eine proximale Anastomose unabhängig von der Fertigungsart ein nicht zu unterschätzendes Risiko für partikuläre Embolien darstellt und somit eine Ursache für neurologische Komplikationen im Rahmen einer Bypassoperation sein kann.
Wir konnten weiterhin zeigen, dass die Anzahl der geborgenen Partikel nach dem Öffnen der Querklemme der Aorta signifikant geringer ist im Vergleich zu der Anzahl der geborgenen Partikel nach dem Fertigen der proximalen Anastomose. Hierbei ist es völlig unerheblich, ob diese Anastomose konventionell oder mit dem Konnektor gefertigt wird.
Wir konnten somit die Behauptung widerlegen, dass die Manipulation an der Aorta durch das Querklemmen im totalen Bypass der entscheidende Faktor für die partikulären Embolien und die konsekutiven neurologischen Komplikationen ist. Mit der Auswertung der Filter konnten wir zeigen, dass durch das Klemmen der Aorta weniger partikuläre Embolien verursacht werden als durch das Fertigen einer proximalen Anastomose am schlagenden Herzen.
In der vorliegenden Untersuchung konnten wir nicht zeigen, dass durch die Verwendung eines mechanischen Konnektors die traumatischen Auswirkungen auf die Aortenwand sowie die entstehenden partikulären Embolien durch das fehlende partielle Ausklemmen der Aortenwand verringert werden kann. Wir konnten zeigen, dass es keinen Unterschied macht, einen mechanischen Konnektor zu verwenden oder aber die proximale Anastomose konventionell mit partieller Ausklemmung der Aortenwand zu fertigen. Neben der Untersuchung der Filter bezüglich der Qualität sowie Quantität der geborgenen Partikel ließen sich in den neurokognitiven Testreihen keine Unterschiede zwischen den zwei Gruppen zeigen. Wir konnten keinen klinischen Vorteil bezüglich des neurokognitiven Outcomes in einer der beiden Gruppen erkennen.
Abschließend kann man sagen, dass es hinsichtlich der Entstehung von partikulären Embolien sowie deren konsekutiven neurologischen Komplikationen keinen Unterschied gibt zwischen der Verwendung des Symmetry™ Aortic Konnektors oder einer konventionell gefertigten Anastomose.
Attenuated NOX2 expression impairs ROS production during the hypoinflammatory phase of sepsis
(2012)
Background: The multicomponent phagocytic NADPH oxidase produces reactive oxygen species (ROS) after activation by microorganisms or inflammatory mediators. In the hypoinflammatory phase of sepsis, macrophages are alternatively activated by contact with apoptotic cells or their secretion products. This inhibits NADPH oxidase and leads to attenuated ROS production and furthermore contributes among others to a hyporeactive host defense. Due to this immune paralysis, sepsis patients suffer from recurrent and secondary infections. We focused on the catalytic subunit of NADPH oxidase, the transmembrane protein NOX2. We assume that after induction of sepsis the expression of NOX2 is reduced and hence ROS production is decreased.
Methods: We induced polymicrobial sepsis in mice by cecal ligation and puncture. The ability of peritoneal macrophages (PMs) to produce ROS was determined by FACS via hydroethidine assay. NOX2 expression of PMs was determined by western blot and qPCR. To elucidate the mechanism causing mRNA destabilization, we performed in vitro experiments using J774 macrophages. To obtain an alternatively activated phenotype, macrophages were stimulated with conditioned medium from apoptotic T cells (CM). By luciferase assays we figured out a 3'UTR-dependent regulation of NOX2 mRNA stability. Assuming that a protein is involved in the mRNA degradation, we performed a RNA pulldown with biotinylated NOX2-3'UTR constructs followed by mass spectrometry. We verified the role of SYNCRIP by siRNA approach. Additionally, we overexpressed NOX2 in J774 cells and analyzed the ROS production (w/wo CM treatment) by FACS.
Results: We found an impaired expression of NOX2 at RNA and protein level along with decreased ROS production after induction of sepsis in mice as well as stimulating J774 macrophages with CM of apoptotic T cells. This is due to a time-dependent NOX2 mRNA degradation depending on SYNCRIP, a RNA-binding protein, which stabilizes NOX2 mRNA through binding to its 3'UTR under normal conditions. In line, knockdown of SYNCRIP also decreases NOX2 mRNA expression. We assume that a CM-dependent modification or degradation of SYNCRIP prevents its stabilizing function. As the overexpression of NOX2 restores ROS production of CM-treated J774 cells, we assume that NOX2 expression is crucial for maintaining NADPH activity during the hypoinflammatory phase of sepsis.
Conclusion: Our data imply a regulatory impact of SYNCRIP on NOX2 stability during the late phase of sepsis. Therefore, further understanding of the regulation of NADPH oxidase could lead to the design of a therapy to reconstitute NADPH oxidase function, finally improving immune function in sepsis patients.
Background: The ligand-activated transcription factor, peroxisome-proliferator-activated receptor gamma (PPARγ), has been shown to play an essential role in immunosuppression during sepsis. PPARγ is upregulated in T cells of septic patients, sensitizing these cells to PPARγ-dependent apoptosis and thus contributing to T-cell depletion. In the polymicrobial cecum ligation and puncture (CLP) sepsis model in mice, both T-cell-specific gene knockout (Lck-Cre PPARγfl/fl) and systemic pharmacological PPARγ antagonism by GW9662 improved survival. Because GW9662 was only effective when applied 3 hours after CLP, we were interested to extend this time frame. For this reason we characterized the kinetics of SPPARγMs when administered before or in combination with the agonist thiazolidinedione, rosiglitazone.
Methods: A PPARγ-dependent transactivation assay was used in HEK293T cells. It is based on the vector pFA-PPARγ-LBD-GAL4-DBD encoding the hybrid protein PPARγ-LBD-GAL4-DBD and the reporter vector pFR-Luc, carrying a GAL4-responsive element in front of the Firefly luciferase gene. These two vectors were co-transfected, in combination with a control vector encoding Renilla luciferase (pRL-CMV) to normalize Firefly luciferase activity for transfection efficiency. Following transfection, cells were incubated with the SPPARγMs F-MOC and MCC-555 and the PPARγ antagonist GW9662 for different times (2 to 48 hours) and at increasing doses (0.01 to 10 μM), with or without rosiglitazone (0.01 to 10 μM). Transactivation was analyzed using a 96-well plate format.
Results: Rosiglitazone transactivated PPARγ in a time-dependent and dose-dependent manner, the response gradually increasing to a maximum at 48 hours with 10 μM. Low concentrations (0.01 to 0.1 μM) of SPPARγMs F-MOC and MCC-555 and the PPARγ antagonist GW9662 all exerted dose-independent antagonistic effects at an early incubation time point (2 hours). From 10 hours onwards, MCC-555 and GW9662, given alone, both exerted PPARγ agonistic effects, MCC-555 in parallel to responses to rosiglitazone, but GW9662 with characteristics of partial antagonism. F-MOC showed no dose-dependent effect at any concentration at later time points. Only GW9662 (1 to 10 μM) was able to inhibit rosiglitazone (0.1 to 1 μM)-induced PPARγ transactivation after 10 hours.
Conclusion: Our kinetic analysis reveals clear differences in the modulatory characteristics of PPARγ inhibitors, with previously unreported early inhibitory effects and late agonistic or partial agonistic activity. New SPPARγMs with extended inhibitory activity may prove useful in the therapy of sepsis.
Background: Undergoing systemic inflammation, the innate immune system releases excessive proinflammatory mediators, which finally can lead to organ failure. Pattern recognition receptors (PRRs), such as Toll-like receptors (TLRs) and NOD-like receptors (NLRs), form the interface between bacterial and viral toxins and innate immunity. During sepsis, patients with diagnosed adrenal gland insufficiency are at high risk of developing a multiorgan dysfunction syndrome, which dramatically increases the risk of mortality. To date, little is known about the mechanisms leading to adrenal dysfunction under septic conditions. Here, we investigated the sepsis-related activation of the PRRs, cell inflammation, and apoptosis within adrenal glands.
Methods: Two sepsis models were performed: the polymicrobial sepsis model (caecal ligation and puncture (CLP)) and the LTA-induced intoxication model. All experiments received institutional approval by the Regierungspräsidium Darmstadt. CLP was performed as previously described [1], wherein one-third of the caecum was ligated and punctured with a 20-gauge needle. For LTA-induced systemic inflammation, TLR2 knockout (TLR2-/-) and WT mice were injected intraperitoneally with pure LTA (pLTA; 1 mg/kg) or PBS for 2 hours. To detect potential direct adrenal dysfunction, mice were additionally injected with adrenocorticotropic hormone (ACTH; 100 μg/kg) 1 hour after pLTA or PBS. Adrenals and plasma samples were taken. Gene expressions in the adrenals (rt-PCR), cytokine release (multiplex assay), and the apoptosis rate (TUNEL assay) within the adrenals were determined.
Results: In both models, adrenals showed increased mRNA expression of TLR2 and TLR4, various NLRs, cytokines as well as inflammasome components, NADPH oxidase subunits, and nitric oxide synthases (data not shown). In WT mice, ACTH alone had no effect on inflammation, while pLTA or pLTA/ACTH administration showed increased levels of the cytokines IL-1β, IL-6, and TNFα. TLR2-/- mice indicated no response as expected (Figure 1, left). Interestingly, surviving CLP mice showed no inflammatory adrenal response, whereas nonsurvivors had elevated cytokine levels (Figure 1, right). Additionally, we identified a marked increase in apoptosis of both chromaffin and steroid-producing cells in adrenal glands obtained from mice with sepsis as compared with their controls (Figure 2).
...
Conclusion: Taken together, sepsis-induced activation of the PRRs may contribute to adrenal impairment by enhancing tissue inflammation, oxidative stress and culminate in cellular apoptosis, while mortality seems to be associated with adrenal inflammation.
Background: Nerve injury induced protein 1 (Ninjurin 1 (Ninj1)) was first identified in Schwann cells and neurons contributing to cell adhesion and nerve regeneration. Recently, the role of Ninj1 has been linked to inflammatory processes in the central nervous system where functional repression reduced leukocyte infiltration and clinical disease activity during experimental autoimmune encephalomyelitis in mice [1]. But Ninj1 is also expressed outside the nervous system in various organs such as the liver and kidney as well as on leukocytes [2,3]. Therefore, we hypothesized that Ninj1 contributes to inflammation in general; that is, also outside the nervous system, with special interest in the pathogenesis of sepsis.
Methods: Ninj1 was repressed by transfecting HMEC-1 cells, a human dermal microvascular endothelial cell line with siRNA targeting Ninj1 (siNinj1) or a negative control (siC). Subsequently, cells were stimulated with 100 ng/ml LPS (TLR4 agonist), 3 μg/ml LTA (TLR2 agonist) or 100 n/ml poly(I:C) (TLR3 agonist) for 3 hours. The inflammatory response was analyzed by real-time PCR. In addition, transmigration of neutrophils across a HMEC-1 monolayer was measured using transwell plates (pore size 3 μm).
Results: Repression of Ninj1 by siRNA reduced Ninj1 mRNA expression in HMEC about 90% (Figure 1A). Reduced Ninj1 expression decreased neutrophil migration to 62.5% (Figure 1B) and TLR signaling. In detail, knockdown of Ninj1 significantly reduced TLR-2 and TLR-4 triggered expression of ICAM-1 and IL-6 (Figure 1C,D) while poly(I:C)-induced expression was only slightly reduced. To analyze a more specific TLR-3 target, we measured IP-10 mRNA expression, which was also significantly reduced in siNinj1-transfected cells (Figure 1E).
Conclusion: Our in vitro data strongly indicated that Ninj1 is involved in regulation of TLR signaling and therewith contributes to inflammation. In vivo experiments will clarify its impact on systemic inflammation.
5-Lipoxygenase contributes to PPAR [gamma] activation in macrophages in response to apoptotic cells
(2012)
Background: One hallmark contributing to immune suppression during the late phase of sepsis is macrophage polarization to an anti-inflammatory phenotype upon contact with apoptotic cells (AC). Taking the important role of the nuclear receptor PPARγ for this phenotype switch into consideration, it remains elusive how AC activate PPARγ in macrophages. Therefore, we were interested to characterize the underlying principle.
Methods: Apoptosis was induced by treatment of Jurkat T cells for 3 hours with 0.5 μg/ml staurosporine. Necrotic cells (NC) were prepared by heating cells for 20 minutes to 65°C. PPARγ activation was followed by stably transducing RAW264.7 macrophages with a vector encoding the red fluorescent protein mRuby after PPARγ binding to 4 × PPRE sites downstream of the reporter gene sequence. This readout was established by treatment with the PPARγ agonist rosiglitazone (1 μM) and AC (5:1). Twenty-four hours after stimulation, mRuby expression was analysed by fluorescence microscopy. Lipid rafts of AC, NC, as well as living cells (LC) were enriched by sucrose gradient centrifugation. Fractions were analysed for lipid raft-associated marker proteins. Lipid rafts were incubated with transduced RAW264.7 macrophages as described above. 5-Lipoxygenase (5-LO) involvement was verified by pharmacological inhibition (MK-866, 1 μM) and overexpression.
Results: Assuming that the molecule responsible for PPARγ activation in macrophages is localized in the cell membrane of AC, most probably associated to lipid rafts, we isolated lipid rafts from AC, NC and LC. Mass spectrometric analysis of lipid rafts of AC showed the expression of 5-LO, whereas lipid rafts of LC did not. Moreover, incubating macrophages with lipid rafts of AC induced mRuby expression. In contrast, lipid rafts of NC and LC did not. To verify the involvement of 5-LO in activating PPARγ in macrophages, Jurkat T cells were incubated for 30 minutes with the 5-LO inhibitor MK-866 (1 μM) before apoptosis induction. In line with our hypothesis, these AC did not induce mRuby expression. Finally, although living Jurkat T cells overexpressing 5-LO did not activate PPARγ in macrophages, mRuby expression was significantly increased when AC were generated from 5-LO overexpressing compared with wild-type Jurkat cells.
Conclusion: Our results suggest that induction of apoptosis activates 5-LO, localizing to lipid rafts, necessary for PPARγ activation in macrophages. Therefore, it will be challenging to determine whether 5-LO activity in AC, generated from other cell types, correlates with PPARγ activation, contributing to an immune-suppressed phenotype in macrophages.
Background: Antithrombotic treatment is a continuous therapy that is often performed in general practice and requires careful safety management. The aim of this study is to investigate whether a best practice model that applies major elements of case management, including patient education, can improve antithrombotic management in primary health care in terms of reducing major thromboembolic and bleeding events.
Methods: This 24-month cluster-randomized trial will be performed in 690 adult patients from 46 practices. The trial intervention will be a complex intervention involving general practitioners, health care assistants and patients with an indication for oral anticoagulation. To assess adherence to medication and symptoms in patients, as well as to detect complications early, health care assistants will be trained in case management and will use the Coagulation-Monitoring-List (Co-MoL) to regularly monitor patients. Patients will receive information (leaflets and a video), treatment monitoring via the Co-MoL and be motivated to perform self-management. Patients in the control group will continue to receive treatment-as-usual from their general practitioners. The primary endpoint is the combined endpoint of all thromboembolic events requiring hospitalization, and all major bleeding complications. Secondary endpoints are mortality, hospitalization, strokes, major bleeding and thromboembolic complications, severe treatment interactions, the number of adverse events, quality of anticoagulation, health-related quality of life and costs. Further secondary objectives will be investigated to explain the mechanism by which the intervention is effective: patients' assessment of chronic illness care, self-reported adherence to medication, general practitioners' and health care assistants' knowledge, patients' knowledge and satisfaction with shared decision making. Practice recruitment is expected to take place between July and December 2012. Recruitment of eligible patients will start in July 2012. Assessment will occur at three time points: baseline (T0), follow-up after 12 (T1) and after 24 months (T2).
Discussion: The efficacy and effectiveness of individual elements of the intervention, such as antithrombotic interventions, self-management concepts in orally anticoagulated patients and the methodological tool, case-management, have already been extensively demonstrated. This project foresees the combination of several proven instruments, as a result of which we expect to profit from a reduction in the major complications associated with antithrombotic treatment.
ABSTRACT: In the original paper (Seidler et al. 2008), there is a mistake in the results of the occupational group analysis. This mistake occurred when the core data set was merged with the occupational group data. According to the modified occupational group analysis (see modified Table 1), OR for chemical processers and manufacturers of plastics products are no longer significantly elevated. Having worked more than 10 years as metal worker is associated with knee osteoarthritis (OR=2.2; 95% CI 1.1-4.4). The knee osteoarthritis risk of plasterers, insulators, glaziers, terrazzo workers, construction carpenters, roofers, and upholsters approaches statistical significance in the long-duration category (OR=3.7; 95% CI 0.9-15.2). For woodworkers, the knee osteoarthritis risk is no longer significantly elevated. Having worked more than 10 years as painter or varnisher is associated with knee osteoarthritis (OR=9.6; 95% CI 1.2-77.9). Finally, we find a significantly elevated OR of 3.2 (95% CI 1.1-9.1) among subjects having worked as physically exposed service workers (storemen, nurses, refuse collectors) for more than 10 years. When subjects with non-service work as main occupation ("blue-collar workers") are compared with "white-collar workers", the odds ratio for knee osteoarthritis is still significantly elevated (OR=2.0; 95% CI 1.3-2.9).
Identification of translationally deregulated proteins during inflammation-associated tumorigenesis
(2012)
The translation of mRNAs into proteins is an elaborate and highly regulated process. Translational regulation primarily takes place at the level of initiation. During initation the eukaryotic initiation factors (eIFs) form a complex that binds to the 5’end of the mRNA to scan for a start codon. Once recognized, the ribosome is recruited to the mRNA and protein synthesis starts. Initiation of translation can basically occur via two distinct mechanisms, i.e. cap-dependent and cap-independent that is mediated via internal ribosome entry sites (IRESs). The former is mediated by a 5’cap structure composed of a 7-methylguanylate which is added to every mRNA during transcription and recruits the initiation complex. IRES-dependent translation involves elements within the 5’untranslated region (UTR) of the mRNA that mostly bind IRES trans-acting factors (ITAFs) which associate either with the initiation complex or with the ribosome itself and consequently allow for internal initiation of translation.
During tumorigenesis the demand for proteins is increased due to rapid cell growth, which consequently requires enhanced translation. Many factors that regulate translation are overexpressed in tumors. Moreover, signaling pathways that trigger translation or further hyperactivated by the surrounding tumor microenvironment. This environment is largely generated by infiltration of immune cells such as macrophages that secrete cytokines and other mediators to promote tumorigenesis. As the effects of inflammatory conditions on the translation of specific targets are only poorly characterized, my study aimed at identifying translationally deregulated targets during inflammation-associated tumorigenesis.
For this purpose, I cocultured MCF7 breast tumor cells with conditioned medium of activated monocyte-derived U937 macrophages (CM). Polysome profiling and microarray analysis identified 42 targets to be regulated at the level of translation. The results were validated by quantitative PCR and one target - early growth response 2 (EGR2) - was chosen for in depth analysis of the mechanism leading to its enhanced translation.
In order to identify upstream signaling molecules causing enhanced EGR2 protein synthesis the cytokine profile of CM was analyzed and the impact of several cytokines on EGR2 translation was examined. Preincubation of CM with neutralizing antibodies revealed that lowering interleukin 6 (IL-6) had only little effect, whereas depletion of IL 1β significantly reduced EGR2 translation. This finding was corroborated by the fact that treatment with recombinant IL-1β enhanced EGR2 translation to virtually the same extend as CM. Further experiments revealed that this effect was mediated via the p38-MAPK signaling cascade.
Interestingly, I observed that the mTOR inhibitor rapamycin, which reduces cap-dependent translation, specifically stimulated EGR2 translation. This result argued for an IRES-dependent mechanism that might account for EGR2 translation. The use of bicistronic reporter assays verified this hypothesis. In line with the above mentioned results, CM, IL-1β and p38-MAPK induced EGR2-IRES activity.
Since IRESs commonly require ITAFs to mediate translation initiation, the binding of proteins to the 5’UTR was analyzed using mass spectrometry. Among others, several previously described ITAFs, such as polypyrimidine tract-binding protein (PTB) and heterogeneous nuclear ribonucleoprotein A1 (hnRNP-A1) were identified to directly bind to the EGR2-5’UTR. Furthermore, overexpression of hnRNP-A1 enhanced EGR2-IRES activity whereas a dominant negative form of hnRNP-A1 significantly decreased it, thus, showing its importance for EGR2 translation.
In summary, my data provide evidence that EGR2 expression can be controlled by IRES-dependent translational regulation, which is responsive to an inflammatory environment. The identified mechanism may not be exclusive for one target but might be representative for gene expression regulation mechanisms during tumorigenesis. This is of special interest for the treatment of cancer patients and development of more specific therapies to reduce tumor outcome.
Introduction: Potential health damage by environmental emission of tobacco smoke (environmental tobacco smoke, ETS) has been demonstrated convincingly in numerous studies. People, especially children, are still exposed to ETS in the small space of private cars. Although major amounts of toxic compounds from ETS are likely transported into the distal lung via particulate matter (PM), few studies have quantified the amount of PM in ETS. Study aim The aim of this study was to determine the ETS-dependent concentration of PM from both a 3R4F reference cigarette (RC) as well as a Marlboro Red brand cigarette (MRC) in a small enclosed space under different conditions of ventilation to model car exposure.
Method: In order to create ETS reproducibly, an emitter (ETSE) was constructed and mounted on to an outdoor telephone booth with an inner volume of 1.75 m3. Cigarettes were smoked under open- and closed-door condition to imitate different ventilation scenarios. PM2.5 concentration was quantified by a laser aerosol spectrometer (Grimm; Model 1.109), and data were adjusted for baseline values. Simultaneously indoor and outdoor climate parameters were recorded. The time of smoking was divided into the ETS generation phase (subset "emission") and a declining phase of PM concentration (subset "elimination"); measurement was terminated after 10 min. For all three time periods the average concentration of PM2.5 (Cmean-PM2.5) and the area under the PM2.5 concentration curve (AUC-PM2.5) was calculated. The maximum concentration (Cmax-PM2.5) was taken from the total interval.
Results: For both cigarette types open-door ventilation reduced the AUC-PM2.5 (RC: from 59 400 +/- 14 600 to 5 550 +/- 3 900 mug*sec/m3; MRC: from 86 500 +/- 32 000 to 7 300 +/- 2 400 mug*sec/m3; p < 0.001) and Cmean-PM2.5 (RC: from 600 +/- 150 to 56 +/- 40 mug/m3, MRC from 870 +/- 320 to 75 +/- 25 mug/m3; p < 0.001) by about 90%. Cmax-PM2.5 was reduced by about 80% (RC: from 1 050 +/- 230 to 185 +/- 125 mug/m3; MRC: from 1 560 +/-500 mug/m3 to 250 +/- 85 mug/m3; p < 0.001). In the subset "emission" we identified a 78% decrease in AUC-PM2.5 (RC: from 18 600 +/- 4 600 to 4 000 +/- 2 600 mug*sec/m3; MRC: from 26 600 +/- 7 200 to 5 800 +/- 1 700 mug*sec/m3; p < 0.001) and Cmean-PM2.5 (RC: from 430 +/- 108 to 93 +/- 60 mug/m3; MRC: from 620 +/- 170 to 134 +/- 40 mug/m3; p < 0.001). In the subset "elimination" we found a reduction of about 96-98% for AUC-PM2.5 (RC: from 40 800 +/- 11 100 to 1 500 +/- 1 700 mug*sec/m3; MRC: from 58 500 +/- 25 200 to 1 400 +/- 800 mug*sec/m3; p < 0.001) and Cmean-PM2.5 (RC: from 730 +/- 200 to 27 +/- 29 mug/m3; MRC: from 1 000 +/- 450 to 26 +/- 15 mug/m3; p < 0.001). Throughout the total interval Cmax-PM2.5 of MRC was about 50% higher (1 550 +/- 500 mug/m3) compared to RC (1 050 +/- 230 mug/m3; p < 0.05). For the subset "emission" - but not for the other periods - AUC-PM2.5 for MRC was 43% higher (MRC: 26 600 +/- 7 200 mug*sec/m3; RC: 18 600 +/- 4 600 mug*sec/m3; p < 0.05) and 44% higher for Cmean-PM2.5 (MRC: 620 +/- 170 mug/m3; RC: 430 +/- 108 mug/m3; p < 0.05).
Conclusion: This method allows reliable quantification of PM2.5-ETS exposure under various conditions, and may be useful for ETS risk assessment in realistic exposure situations. The findings demonstrate that open-door condition does not completely remove ETS from a defined indoor space of 1.75 m3. Because there is no safe level of ETS exposure ventilation is not adequate enough to prevent ETS exposure in confined spaces, e.g. private cars. Additionally, differences in the characteristics of cigarettes affect the amount of ETS particle emission and need to be clarified by ongoing investigations.
kurz und kn@pp news : Nr. 26
(2012)
* Prof. Gerlach ist der neue Vorsitzende des "Sachverständigenrates Gesundheit"
* Prof. Marjan van den Akker - 22. Friedrich-Merz-Stiftungsgastprofessur
* Internationales Symposium am 17.10.2012 in der Deutschen Nationalbibliothek, Frankfurt
* Projekt InGe- Innovative Gesundheitsmodelle
* Kompetenznetzwerk Komplementärmedizin in der Onkologie (KOKON): Studie zu Informationsbedürfnissen
* Kompetenzzentren Weiterbildung Allgemeinmedizin der Universitäten Marburg und Frankfurt am Main unter www.weiterbildung.allgemeinmedizin-hessen.de
The E4 allele of the ApoE gene has consistently been shown to be related to an increased risk of Alzheimer's disease (AD). The E4 allele is also associated with functional and structural grey matter (GM) changes in healthy young, middle-aged and older subjects. Here, we assess volumes of deep grey matter structures of 22 healthy younger ApoE4 carriers and 22 non-carriers (20–38 years). Volumes of the nucleus accumbens, amygdala, caudate nucleus, hippocampus, pallidum, putamen, thalamus and brain stem were calculated by FMRIB's Integrated Registration and Segmentation Tool (FIRST) algorithm. A significant drop in volume was found in the right hippocampus of ApoE4 carriers (ApoE4+) relative to non-carriers (ApoE4−), while there was a borderline significant decrease in the volume of the left hippocampus of ApoE4 carriers. The volumes of no other structures were found to be significantly affected by genotype. Atrophy has been found to be a sensitive marker of neurodegenerative changes, and our results show that within a healthy young population, the presence of the ApoE4+ carrier gene leads to volume reduction in a structure that is vitally important for memory formation. Our results suggest that the hippocampus may be particularly vulnerable to further degeneration in ApoE4 carriers as they enter middle and old age. Although volume reductions were noted bilaterally in the hippocampus, atrophy was more pronounced in the right hippocampus. This finding relates to previous work which has noted a compensatory increase in right hemisphere activity in ApoE4 carriers in response to preclinical declines in memory function. Possession of the ApoE4 allele may lead to greater predilection for right hemisphere atrophy even in healthy young subjects in their twenties.