Die Rolle des Integrin-linked Kinase Signalweges im Herzmuskel : Genetische und pharmakologische Analysen im Zebrafischmodell

In einem forward genetics screen konnte kürzlich eine Integrin-linked Kinase (ILK)-defiziente Zebrafischmutante, main squeeze (msq), isoliert werden. Main squeeze mutante Embryonen zeichnen sich durch den progredienten Verlust der Kardiomyozy-tenkontraktilität aus. Es konnte gezeigt werden, dass die msq-Mutation zu einer verminderten ILK-Kinaseaktivität sowie zum Verlust der beta-Parvin-Bindefähigkeit führt, was in einer signifikant reduzierten Protein Kinase B (PKB) Aktivität resultiert. In Patienten konnten mittlerweile Mutationen in der ILK identifiziert werden, die zu genetisch bedingter Herzschwäche (DCM, dilatative Kardiomyopathie) führen. Ziel dieser Arbeit war die Etablierung von in vivo Modellen zur Entschlüsselung der molekularen Funktionen der ILK in Herzmuskelzellen. Durch diese genetischen Ansätze kann geklärt werden, ob die Kinasedomäne der ILK oder die Bindungsfähigkeit zu beta-Parvin für die Funktion der ILK in der Aufrechterhaltung der kardialen Kontraktilität von Bedeutung sind. Dazu wurden definierte ILK-Varianten (Kinase-defizient, konstitutiv-aktiv, Wildtyp) in vivo im Zebrafisch evaluiert. Des Weiteren sollte durch die pharmakologische Manipulation des ILK/PKB Signalweges mit small compounds geklärt werden, ob Substanzen, die die PKB-Phosphorylierung beeinflussen, einen rescue des Herzinsuffizienzphänotyps bewirken können. In der vorliegenden Arbeit konnten verschiedene Genexpressionssysteme zur Generie-rung transgener Zebrafische mit herzspezifischer ILK-Überexpression entwickelt und deren Funktion überprüft werden. Weiterhin wurden erstmals stabile, induzierbare transgene Zebrafischlinien mit kardialer Überexpression von ILK-Varianten (Kinase-defizient, konstitutiv-aktiv, Wildtyp) etabliert. Durch Anwendung der pharmakologi-schen Substanzen Cyclosporin A, Okadasäure und Calyculin A konnte gezeigt werden, dass die Phosphorylierung der PKB im Herzen erhöht und die Kontraktionskraft in msq rekonstituiert werden kann. Die in dieser Arbeit entwickelten Ansätze ermöglichen in Zukunft ein besseres Ver-ständnis der ILK-Funktion im Myokard. Auch die therapeutische Beeinflussung von Komponenten des ILK/PKB-Signalweges kann richtungsweisende Therapieansätze für Patienten mit Herzerkrankungen aufzeigen

SchussenAktivplus: reduction of micropollutants and of potentially pathogenic bacteria for further water quality improvement of the river Schussen, a tributary of Lake Constance, Germany

The project focuses on the efficiency of combined technologies to reduce the release of micropollutants and bacteria into surface waters via sewage treatment plants of different size and via stormwater overflow basins of different types. As a model river in a highly populated catchment area, the river Schussen and, as a control, the river Argen, two tributaries of Lake Constance, Southern Germany, are under investigation in this project. The efficiency of the different cleaning technologies is monitored by a wide range of exposure and effect analyses including chemical and microbiological techniques as well as effect studies ranging from molecules to communities

A Human-Curated Annotation of the Candida albicans Genome

Recent sequencing and assembly of the genome for the fungal pathogen Candida albicans used simple automated procedures for the identification of putative genes. We have reviewed the entire assembly, both by hand and with additional bioinformatic resources, to accurately map and describe 6,354 genes and to identify 246 genes whose original database entries contained sequencing errors (or possibly mutations) that affect their reading frame. Comparison with other fungal genomes permitted the identification of numerous fungus-specific genes that might be targeted for antifungal therapy. We also observed that, compared to other fungi, the protein-coding sequences in the C. albicans genome are especially rich in short sequence repeats. Finally, our improved annotation permitted a detailed analysis of several multigene families, and comparative genomic studies showed that C. albicans has a far greater catabolic range, encoding respiratory Complex 1, several novel oxidoreductases and ketone body degrading enzymes, malonyl-CoA and enoyl-CoA carriers, several novel amino acid degrading enzymes, a variety of secreted catabolic lipases and proteases, and numerous transporters to assimilate the resulting nutrients. The results of these efforts will ensure that the Candida research community has uniform and comprehensive genomic information for medical research as well as for future diagnostic and therapeutic applications

Atlas of the clinical genetics of human dilated cardiomyopathy

[Abstract] Aim. Numerous genes are known to cause dilated cardiomyopathy (DCM). However, until now technological limitations have hindered elucidation of the contribution of all clinically relevant disease genes to DCM phenotypes in larger cohorts. We now utilized next-generation sequencing to overcome these limitations and screened all DCM disease genes in a large cohort. Methods and results. In this multi-centre, multi-national study, we have enrolled 639 patients with sporadic or familial DCM. To all samples, we applied a standardized protocol for ultra-high coverage next-generation sequencing of 84 genes, leading to 99.1% coverage of the target region with at least 50-fold and a mean read depth of 2415. In this well characterized cohort, we find the highest number of known cardiomyopathy mutations in plakophilin-2, myosin-binding protein C-3, and desmoplakin. When we include yet unknown but predicted disease variants, we find titin, plakophilin-2, myosin-binding protein-C 3, desmoplakin, ryanodine receptor 2, desmocollin-2, desmoglein-2, and SCN5A variants among the most commonly mutated genes. The overlap between DCM, hypertrophic cardiomyopathy (HCM), and channelopathy causing mutations is considerably high. Of note, we find that >38% of patients have compound or combined mutations and 12.8% have three or even more mutations. When comparing patients recruited in the eight participating European countries we find remarkably little differences in mutation frequencies and affected genes. Conclusion. This is to our knowledge, the first study that comprehensively investigated the genetics of DCM in a large-scale cohort and across a broad gene panel of the known DCM genes. Our results underline the high analytical quality and feasibility of Next-Generation Sequencing in clinical genetic diagnostics and provide a sound database of the genetic causes of DCM.Hôpitaux de Paris; PHRC AOM0414

Gazette de Bayonne, de Biarritz et du Pays basque

08 août 19391939/08/08 (A48,N9520).Appartient à l’ensemble documentaire : Aquit

Improved Recovery from Liver Fibrosis by Crenolanib

Chronic liver diseases are associated with excessive deposition of extracellular matrix proteins. This so-called fibrosis can progress to cirrhosis and impair vital functions of the liver. We examined whether the receptor tyrosine kinase (RTK) class III inhibitor Crenolanib affects the behavior of hepatic stellate cells (HSC) involved in fibrogenesis. Rats were treated with thioacetamide (TAA) for 18 weeks to trigger fibrosis. After TAA treatment, the animals received Crenolanib for two weeks, which significantly improved recovery from liver fibrosis. Because Crenolanib predominantly inhibits the RTK platelet-derived growth factor receptor-β, impaired HSC proliferation might be responsible for this beneficial effect. Interestingly, blocking of RTK signaling by Crenolanib not only hindered HSC proliferation but also triggered their specification into hepatic endoderm. Endodermal specification was mediated by p38 mitogen-activated kinase (p38 MAPK) and c-Jun-activated kinase (JNK) signaling; however, this process remained incomplete, and the HSC accumulated lipids. JNK activation was induced by stress response-associated inositol-requiring enzyme-1α (IRE1α) in response to Crenolanib treatment, whereas β-catenin-dependent WNT signaling was able to counteract this process. In conclusion, the Crenolanib-mediated inhibition of RTK impeded HSC proliferation and triggered stress responses, initiating developmental processes in HSC that might have contributed to improved recovery from liver fibrosis in TAA-treated rats

Smartwatch-Based Interventions for People With Dementia: User-Centered Design Approach

BackgroundAssistive technologies can help people living with dementia maintain their everyday activities. Nevertheless, there is a gap between the potential and use of these materials. Involving future users may help close this gap, but the impact on people with dementia is unclear. ObjectiveWe aimed to determine if user-centered development of smartwatch-based interventions together with people with dementia is feasible. In addition, we evaluated the extent to which user feedback is plausible and therefore helpful for technological improvements. MethodsWe examined the interactions between smartwatches and people with dementia or people with mild cognitive impairment. All participants were prompted to complete 2 tasks (drinking water and a specific cognitive task). Prompts were triggered using a smartphone as a remote control and were repeated up to 3 times if participants failed to complete a task. Overall, 50% (20/40) of the participants received regular prompts, and 50% (20/40) received intensive audiovisual prompts to perform everyday tasks. Participants’ reactions were observed remotely via cameras. User feedback was captured via questionnaires, which included topics like usability, design, usefulness, and concerns. The internal consistency of the subscales was calculated. Plausibility was also checked using qualitative approaches. ResultsParticipants noted their preferences for particular functions and improvements. Patients struggled with rating using the Likert scale; therefore, we assisted them with completing the questionnaire. Usability (mean 78 out of 100, SD 15.22) and usefulness (mean 9 out of 12) were rated high. The smartwatch design was appealing to most participants (31/40, 76%). Only a few participants (6/40, 15%) were concerned about using the watch. Better usability was associated with better cognition. The observed success and self-rated task comprehension were in agreement for most participants (32/40, 80%). In different qualitative analyses, participants’ responses were, in most cases, plausible. Only 8% (3/40) of the participants were completely unaware of their irregular task performance. ConclusionsPeople with dementia can have positive experiences with smartwatches. Most people with dementia provided valuable information. Developing assistive technologies together with people with dementia can help to prioritize the future development of functional and nonfunctional features

Does wastewater treatment plant upgrading with activated carbon result in an improvement of fish health?

International audienceIn the present study, the efficiency of a wastewater treatment plant (WWTP) upgraded with a powdered activated carbon unit for the reduction of micropollutants and the related advantages for fish health have been analyzed by means of different biomarkers, i.e. histopathological investigations, analyses of glycogen content and stress proteins, as well as by chemical analyses in different matrices. Comparative analyses were conducted prior and subsequent to the installation of the additional purification unit. Chemical analyses revealed a significant reduction of several pharmaceuticals, including diclofenac, carba-mazepine and metoprolol, in samples of effluent and surface water downstream of the WWTP after its upgrade. In addition, diminished concentrations of diclofenac and PFOS were detected in tissues of analyzed fish. Histopathological investigations of fish liver, gills, and kidney revealed improved tissue integrity in fish after improved wastewater treatment. In parallel, biochemical measurements of glycogen revealed increased energy resources in fish liver and, furthermore, hsp70 levels in livers of exposed rainbow trout and in kidneys of exposed brown trout were lower after than before the WWTP upgrade. In summary, additional treatment with powdered activated carbon led to a reduction of potentially hazardous chemicals in the effluent and the adjacent river and, consequently, to an improvement of fish health in the receiving water course