3,782 results on '"ddc:610"'
Search Results
2. The Adaptive Mind Data and Code Policy
- Author
-
Brand, Ortrun, Endres, Dominik, Pfarr, Julia-Katharina, Berger, Christian, Lenze, Stefan, Fiehler, Katja, Fleming, Roland W., and Justus Liebig University Giessen
- Subjects
ddc:004 ,ddc:610 ,Data and Code Policy ,Open Science ,Open Data ,Research Data Management ,ddc:150 ,The Adaptive Mind ,FAIR - Abstract
This document outlines the policy of the excellence cluster initiative The Adaptive Mind (TAM) with regards to research data and code management as well as data and code sharing, both internally and externally. It fosters an Open Science approach including early and broad sharing of data and code to leverage collaboration and ultimately improve the quality and efficiency of science.
- Published
- 2023
- Full Text
- View/download PDF
3. Postpyloric nutrition to prevent emergencies - a step away from repeat inpatient care in children with methylmalonic acidaemia and propionic acidaemia - a case report of four cases
- Author
-
Schumann, Stefan, Rommel, Frank Risto, Cantez, Serdar, Alexanidou, Evdokia, Kamrath, Clemens, de Laffolie, Jan, and Justus Liebig University Giessen
- Subjects
postpyloric nutrition ,J-PEG ,ddc:610 ,metabolic decompensation ,prevention of emergencies ,MMA ,methylmalonic acidaemia ,propionic acidaemia ,PA - Abstract
Methylmalonic acidaemia (MMA) and propionic acidaemia (PA) are very rare autosomal recessive inherited metabolic diseases from the group of organoacidopathies. Katabolism due to minor infections can lead to metabolic decompensation including hyperammonemia and ketoacidosis, especially in small children. We present data from a small cohort to clarify whether placement of a percutaneous endoscopic gastrostomy with jejunal tube (J-PEG) reduce metabolic imbalances and hospital stays. The aim is to prevent emergencies from occurring by preventing metabolic derailments at an early stage. 4 patients with MMA (N = 3) or PA (N = 1) were included. Data were collected at every investigation, in particular pH value, pCO2, bicarbonate, base excess, ammonia and lactate. Due to repeated metabolic derailments, a percutaneous endoscopic gastrostomy was placed for postpyloric nutrition. In conclusion, placement of a percutaneous endoscopic gastrostomy with postpyloric tube appears to reduce the rate of metabolic decompensations. In addition, hospital stays and especially the number of treatment days can be reduced. This method, especially the placement of a postpyloric tube could enable parents to prevent catabolism when vomiting begins by continuously feeding through the jejunal part, as a step to prevent a metabolic emergency from occurring.
- Published
- 2023
- Full Text
- View/download PDF
4. Menschenrechtsdiskurse in der Migrationsgesellschaft. Eine Forschungsagenda
- Author
-
Bast, Jürgen, Buckley-Zistel, Susanne, Gutiérrez Rodríguez, Encarnación, Hailbronner, Michaela, Knipper, Michael, Olson, Greta, von Harbou, Frederik, Wessels, Janna, Wiezorek, Christine, Zifonun, Dariuš, and Justus Liebig University Giessen
- Subjects
ddc:610 ,Praxistheorie ,Menschenrechte ,ddc:320 ,ddc:300 ,ddc:370 ,ddc:340 ,ddc:800 ,Diskurs ,Migration ,Vermenschenrechtlichung ,Migrationsgesellschaft - Abstract
Das Working Paper skizziert die Forschungsagenda der interdisziplinären Forschungsgruppe "Menschenrechtsdiskurse in der Migrationsgesellschaft" (MeDiMi). MeDiMi untersucht die Reichweite, Formen und Folgen des Vordringens von Menschenrechtsdiskursen in Migrationsgesellschaften. Die zeitdiagnostische Ausgangsbeobachtung lautet, dass migrationsgesellschaftliche Akteure in ihrer diskursiven Praxis heute vielfach auf Menschenrechtsnormen Bezug nehmen, um ihre Selbstverständnisse und Interessen zu artikulieren. Diesen Vorgang bezeichnen wir schlagwortartig als „Vermenschenrechtlichung“. Die Vermenschenrechtlichung migrationsgesellschaftlicher Diskurse wird in drei Handlungskontexten untersucht: im Rechtssystem, in politischen Handlungskontexten und in weiteren – professionellen oder alltäglichen – soziokulturellen Kontexten, in denen Selbstverständnisse und Haltungen migrationsgesellschaftlicher Akteure artikuliert und geformt werden. Die rechts-, sozial- und kulturwissenschaftliche Analyse von zehn ausgewählten Untersuchungsfeldern bildet die empirische Grundlage für eine Theorie migrationsgesellschaftlicher Diskurspraxis und ermöglicht so ein neues Verständnis der Rolle der Menschenrechte in kontemporären – insbesondere europäischen – Gesellschaften.
- Published
- 2023
- Full Text
- View/download PDF
5. Sex Difference in Cardioprotection against Acute Myocardial Infarction in MAO-B Knockout Mice In Vivo
- Author
-
Heger, Jacqueline, Szabados, Tamara, Brosinsky, Paulin, Bencsik, Péter, Ferdinandy, Péter, Schulz, Rainer, and Justus Liebig University Giessen
- Subjects
mitochondria ,ddc:610 ,monoamine oxidase B ,ischemia/reperfusion - Abstract
The cardiomyocyte-specific knockout (KO) of monoamine oxidase (MAO)-B, an enzyme involved in the formation of reactive oxygen species (ROS), reduced myocardial ischemia/reperfusion (I/R) injury in vitro. Because sex hormones have a strong impact on MAO metabolic pathways, we analyzed the myocardial infarct size (IS) following I/R in female and male MAO-B KO mice in vivo. Method and Results: To induce the deletion of MAO-B, MAO-B KO mice (Myh6 Cre+/MAO-Bfl/fl) and wild-type (WT, Cre-negative MAO-Bfl/fl littermates) were fed with tamoxifen for 2 weeks followed by 10 weeks of normal mice chow. Myocardial infarction (assessed by TTC staining and expressed as a percentage of the area at risk as determined by Evans blue staining)) was induced by 45 min coronary occlusion followed by 120 min of reperfusion. Results: The mortality following I/R was higher in male compared to female mice, with the lowest mortality found in MAO-B KO female mice. IS was significantly higher in male WT mice compared to female WT mice. MAO-B KO reduced IS in male mice but had no further impact on IS in female MAO-B KO mice. Interestingly, there was no difference in the plasma estradiol levels among the groups. Conclusion: The cardiomyocyte-specific knockout of MAO-B protects male mice against acute myocardial infarction but had no effect on the infarct size in female mice.
- Published
- 2023
- Full Text
- View/download PDF
6. Orthodontic Compression Enhances Macrophage M2 Polarization via Histone H3 Hyperacetylation
- Author
-
Wang, Yao, Groeger, Sabine, Yong, Jiawen, Ruf, Sabine, and Justus Liebig University Giessen
- Subjects
polarization ,ddc:610 ,H3 histone ,compressive force ,adiponectin ,macrophages ,acetylation - Abstract
Orthodontic tooth movement is a complex periodontal remodeling process triggered by compression that involves sterile inflammation and immune responses. Macrophages are mechanically sensitive immune cells, but their role in orthodontic tooth movement is unclear. Here, we hypothesize that orthodontic force can activate macrophages, and their activation may be associated with orthodontic root resorption. After force-loading and/or adiponectin application, the migration function of macrophages was tested via scratch assay, and Nos2, Il1b, Arg1, Il10, ApoE, and Saa3 expression levels were detected using qRT-PCR. Furthermore, H3 histone acetylation was measured using an acetylation detection kit. The specific inhibitor of H3 histone, I-BET762, was deployed to observe its effect on macrophages. In addition, cementoblasts were treated with macrophage-conditioned medium or compression force, and OPG production and cellular migration were measured. We further detected Piezo1 expression in cementoblasts via qRT-PCR and Western-blot, and its effect on the force-induced impairment of cementoblastic functions was also analyzed. Compressive force significantly inhibited macrophage migration. Nos2 was up-regulated 6 h after force-loading. Il1b, Arg1, Il10, Saa3, and ApoE increased after 24 h. Meanwhile, higher H3 histone acetylation was detected in the macrophages subjected to compression, and I-BET762 dampened the expression of M2 polarization markers (Arg1 and Il10). Lastly, even though the activated macrophage-conditioned medium showed no effect on cementoblasts, compressive force directly impaired cementoblastic function by enhancing mechanoreceptor Piezo1. Compressive force activates macrophages; specifically, it causes M2 polarization via H3 histone acetylation in the late stage. Compression-induced orthodontic root resorption is macrophage-independent, but it involves the activation of mechanoreceptor Piezo1.
- Published
- 2023
- Full Text
- View/download PDF
7. Versorgung von Patienten mit einer gerüstlosen Aortenklappenprothese
- Author
-
Meilwes, Markus and Justus Liebig University Giessen
- Subjects
ddc:610 ,stentless ,Follow-Up ,ddc:430 ,Aortenklappe - Abstract
Langzeit-follow-up über 17 Jahre von Patienten mit einer gerüstfreien Aortenklappenprothese vom Typ Medtronic freestyle.
- Published
- 2023
- Full Text
- View/download PDF
8. Robotic operations in urgent general surgery: a systematic review
- Author
-
Reinisch, Alexander, Liese, Juliane, Padberg, Winfried, Ulrich, Frank, and Justus Liebig University Giessen
- Subjects
ddc:610 - Published
- 2023
- Full Text
- View/download PDF
9. Bioactive Azadirachta indica and Melia azedarach leaves extracts with anti-SARS-CoV-2 and antibacterial activities
- Author
-
Hemdan, Bahaa A., Mostafa, Ahmed, Elbatanony, Marwa M., El-Feky, Amal M., Paunova-Krasteva, Tsvetelina, Stoitsova, Stoyanka, El-Liethy, Mohamed Azab, El-Taweel, Gamila E., Abu Mraheil, Mobarak, and Justus Liebig University Giessen
- Subjects
ddc:610 - Abstract
The leaves of Azadirachta indica L. and Melia azedarach L., belonging to Meliaceae family, have been shown to have medicinal benefits and are extensively employed in traditional folk medicine. Herein, HPLC analysis of the ethyl acetate fraction of the total methanolic extract emphasized the enrichment of both A. indica L., and M. azedarach L. leaves extracts with phenolic and flavonoids composites, respectively. Besides, 4 limonoids and 2 flavonoids were isolated using column chromatography. By assessing the in vitro antiviral activities of both total leaves extracts against Severe Acute Respiratory Syndrome Corona virus 2 (SARS-CoV-2), it was found that A. indica L. and M. azedarach L. have robust anti-SARSCoV- 2 activities at low half-maximal inhibitory concentrations (IC50) of 8.451 and 6.922 μg/ mL, respectively. Due to the high safety of A. indica L. and M. azedarach L. extracts with half-maximal cytotoxic concentrations (CC50) of 446.2 and 351.4 μg/ml, respectively, both displayed extraordinary selectivity indices (SI>50). A. indica L. and M. azedarach L. leaves extracts could induce antibacterial activities against both Gram-negative and positive bacterial strains. The minimal inhibitory concentrations of A. indica L. and M. azedarach L. leaves extracts varied from 25 to 100 mg/mL within 30 min contact time towards the tested bacteria. Our findings confirm the broad-spectrum medicinal value of A. indica L. and M. azedarach L. leaves extracts. Finally, additional in vivo investigations are highly recommended to confirm the anti-COVID-19 and antimicrobial activities of both plant extracts.
- Published
- 2023
- Full Text
- View/download PDF
10. Complication and Infection Risk Using Bone Substitute Materials to Treat Long Bone Defects in Geriatric Patients: An Observational Study
- Author
-
Pawelke, Jonas, Vinayahalingam, Vithusha, El Khassawna, Thaqif, Heiss, Christian, Eckl, Larissa, Knapp, Gero, and Justus Liebig University Giessen
- Subjects
ddc:610 ,trauma ,humerus ,falls ,geriatric ,bone substitute ,low impact ,osteoporosis ,radius ,tibia - Abstract
Background and Objectives: he treatment of large bone defects in geriatric patients often presents a major surgical challenge because of age-related bone loss. In such patients, the scarcity of healthy makes autologous grafting techniques hard to perform. On the one hand, clinicians’ fear of possible infections limits using bone substitute materials (BSM). On the other hand, BSM is limitless and spares patients another surgery to harvest autologous material. Materials and Methods: To address the aptness of BSM in geriatric patients, we performed a retrospective analysis of all patients over the age of 64 years who visited our clinic between the years 2011–2018. The study assessed postoperative complications clinically and healing results radiologically. The study included 83 patients with bone defects at the distal radius, proximal humerus, and proximal tibia. The defect zones were filled with BSM based on either nanocrystalline hydroxyapatite (NHA) or calcium phosphate (CP). For comparison, a reference group (empty defect, ED) without the void filling with a BSM was also included. Results: 106 patients sustained traumatic fractures of the distal radius (71.7%), proximal humerus (5.7%), and proximal tibia (22.6%). No difference was found between the BSM groups in infection occurrence (p = 1.0). Although not statistically significant, the BSM groups showed a lower rate of pseudarthrosis (p = 0.09) compared with the ED group. Relative risk (RR) of complications was 32.64% less in the BSM groups compared with the ED group. The additional beneficial outcome of BSM was demonstrated by calculating the number needed to treat (NNT). The calculation showed that with every six patients treated, at least one complication could be avoided. Radiological assessment of bone healing showed significant improvement in the bridging of the defect zone (p < 0.001) when BSM was used. Conclusions: In contrast to previous studies, the study showed that BSM could support bone healing and does not present an infection risk in geriatric patients. The NNT calculation indicates a wider potential benefit of BSM.
- Published
- 2023
- Full Text
- View/download PDF
11. Peroxisomes Are Highly Abundant and Heterogeneous in Human Parotid Glands
- Author
-
Watermann, Christoph, Meyer, Malin Tordis, Wagner, Steffen, Wittekindt, Claus, Klussmann, Jens Peter, Erguen, Sueleyman, Baumgart-Vogt, Eveline, Karnati, Srikanth, and Justus Liebig University Giessen
- Subjects
PSP ,ddc:610 ,mRNA ,catalase ,peroxisomes ,human ,immunofluorescence ,parotid gland ,differential expression - Abstract
The parotid gland is one of the major salivary glands producing a serous secretion, and it plays an essential role in the digestive and immune systems. Knowledge of peroxisomes in the human parotid gland is minimal; furthermore, the peroxisomal compartment and its enzyme composition in the different cell types of the human parotid gland have never been subjected to a detailed investigation. Therefore, we performed a comprehensive analysis of peroxisomes in the human parotid gland’s striated duct and acinar cells. We combined biochemical techniques with various light and electron microscopy techniques to determine the localization of parotid secretory proteins and different peroxisomal marker proteins in parotid gland tissue. Moreover, we analyzed the mRNA of numerous gene encoding proteins localized in peroxisomes using real-time quantitative PCR. The results confirm the presence of peroxisomes in all striated duct and acinar cells of the human parotid gland. Immunofluorescence analyses for various peroxisomal proteins showed a higher abundance and more intense staining in striated duct cells compared to acinar cells. Moreover, human parotid glands comprise high quantities of catalase and other antioxidative enzymes in discrete subcellular regions, suggesting their role in protection against oxidative stress. This study provides the first thorough description of parotid peroxisomes in different parotid cell types of healthy human tissue.
- Published
- 2023
- Full Text
- View/download PDF
12. Einfluss Endothelialer Progenitorzellen auf die Revaskularisation mikrovaskulärer anastomosierter Fernlappentransplantate
- Author
-
Jäger, Lukas and Justus Liebig University Giessen
- Subjects
Lappentransplantate ,Stammzellen ,ddc:610 ,Ratten ,Tierversuch ,ddc:630 ,EPC ,Mikrovaskuläre Anastomosen ,Angiogenese ,Endotheliale Progenitorzellen - Abstract
Freie Lappentransplantate sind eine verbreitete, aber sehr anspruchsvolle Methode der plastischen Chirurgie zur Deckung komplizierter Wunden. Um Komplikationen bei diesen Eingriffen zu verringern, könnte der Einsatz von Endothelialen Progenitorzellen (EPC) nützlich sein. Diese Zellen haben in vielen Untersuchungen positive Effekte auf die Neovaskularisation von Geweben gezeigt. Teils bewirken sie über parakrine Effekte eine Steigerung der Angiogenese oder werden direkt in neue Gefäße inkorporiert. In der vorliegenden Studie wird daher die Hypothese untersucht, dass EPC die Vaskularisation von freien Lappentransplantaten und damit deren Wundheilung verbessern. Im Tiermodell werden freie Lappen transplantiert, wobei zunächst die von Miyamoto und Kollegen beschriebene Operationsmethode in einigen Punkten modifiziert werden muss, um die Erfolgsrate zu steigern. Ebenfalls werden im Rahmen eines Vorversuchs die Gefäßarchitektur und histologische Parameter zu verschiedenen Entnahmezeitpunkten verglichen. Der siebte postoperative Tag wird als Entnahmezeitpunkt für den Hauptversuch ausgewählt, da sich hier die größten Unterschiede zwischen den Transplantaten und den Kontrollgeweben zeigen. Im Hauptversuch erhalten die Tiere entweder subkutan oder intraarteriell EPC bzw. in der Kontrollgruppe keine EPC. An den entnommenen Transplantaten wird histologisch die Vaskularisation und elektronenmikroskopisch (Raster-Elektronen-Mikroskop, REM) die Gefäßarchitektur untersucht. Auf eine Zugdehnungsmessung der Wundränder muss aufgrund der hohen Fragilität der Wundränder verzichtet werden. Histologisch kann eine signifikante Steigerung der Gefäßanzahl bei den Behandlungsgruppen um 39 % (EPC intraarteriell) bzw. 45 % (EPC subkutan) gegenüber der Kontrollgruppe festgestellt werden, wobei keine Applikationsart der EPC der anderen überlegen ist. Hinsichtlich der Dicke der Hautschichten und der Proliferationsrate ergaben sich keine signifikanten Unterschiede. Bei der Untersuchung der dreidimensionalen Gefäßarchitektur (Gefäßdurchmesser, Gefäßabstand, Aufzweigungswinkel und Abstand der Gefäßaufzweigungen) ergeben sich keine signifikanten Unterschiede, welche gegebenenfalls zu einem früheren Untersuchungszeitpunkt darstellbar sein könnten. In den REM-Untersuchungen lässt sich kein signifikanter Unterschied im Auftreten von pillars und sprouts feststellen, da vermutlich der Großteil der SA bereits vor dem Untersuchungszeitpunkt passiert und die IA erst anzulaufen beginnt. Die aus anderen Anwendungsgebieten bekannten positiven Effekte der EPC auf die Neovaskularisation können anhand dieser Studie auch bei freien Lappentransplantaten nachgewiesen werden. Aufgabe zukünftiger Studien wäre es, die Art und Weise der proangiogenen Wirkungen zu untersuchen und den Einfluss der EPC auf die funktionelle Wundheilung, z.B. durch Überprüfung der Wundfestigkeit. Veterinärmedizinisch bedeutsam wäre die weitere Erforschung von spezieseigenen EPC und deren Effekten im Tierkörper.
- Published
- 2023
- Full Text
- View/download PDF
13. Vorteile des ventrikuloperitonealen Shunts bei Patienten mit Normaldruckhydrozephalus im Follow-up von drei Jahren
- Author
-
Gencer, Aylin Hic and Justus Liebig University Giessen
- Subjects
Normaldruckhydrozephalus ,ddc:610 ,ventrikuloperitonealer Shunt ,Neurochirurgie ,Evans-Index ,Corpus-Callosum-Winkel ,Hakim-Trias ,VP-Shunt - Abstract
Die Implantation eines ventrikuloperitonealen (VP-) Shunts stellt eine bewährte Behandlungsmethode für Patienten mit Normaldruckhydrozephalus (NPH) dar. Ziel dieser retrospektiven Studie war es, die Auswirkungen dieser Operation auf die Patienten im Langzeitverlauf zu untersuchen, mögliche Zusammenhänge zwischen den Komorbiditäten und den Behandlungsergebnissen zu finden und einen optimalen Öffnungsdruck des programmierbaren Ventils in Abhängigkeit vom Geschlecht zu ermitteln. Die VP-Shunt-Implantation ist im Hinblick auf die klinischen und radiologischen Ergebnisse wirksam. Eine signifikante Verbesserung aller drei untersuchten Symptome war innerhalb der ersten 6 Monate nach der Operation am deutlichsten (p < 0,01), wobei die Verbesserung der Gangstörung im Vordergrund stand. Die postoperative klinische Verbesserung blieb während des langfristigen Follow-up-Zeitraums weitestgehend erhalten. In ähnlicher Weise nahmen der Evans-Index und der Corpus-Callosum-Winkel nach dem VP-Shunt signifikant ab bzw. zu (p < 0,05) und blieben auch langfristig auf dem verbesserten Niveau. Es konnte hingegen kein signifikanter Zusammenhang zwischen dem Rückgang der Symptome und der Verbesserung des Evans-Index oder des Corpus-Callosum-Winkels festgestellt werden. Daraus lässt sich schlussfolgern, dass die radiologischen Marker zwar als potenzielle Verlaufsparameter von Interesse sind, diese sollten aber dennoch nicht bei den Kontrolluntersuchungen Vorrang vor der Klinik haben. Vorbestehende Komorbiditäten haben Einfluss auf den Krankheitsverlauf. Sowohl ein Diabetes mellitus als auch ein Schlaganfall weisen signifikante Korrelationen mit den präoperativen Zuständen und den klinischen sowie radiologischen Ergebnissen (p < 0,05) auf. Den Vorerkrankungen sollte daher bei der Behandlung Beachtung geschenkt werden. Bei der Wahl der Ventileinstellung sollte das Geschlecht des Patienten berücksichtigt werden. Der mediane Öffnungsdruck in Abhängigkeit vom Geschlecht und der allgemeinen Symptomkontrolle wurde als 120 mmH2O für Frauen und 140 mmH2O für Männer ermittelt. Diese Werte sind für die initiale Einstellung zu empfehlen. Weitere prospektive Studien sind erforderlich, um die Ergebnisse dieser Arbeit zu validieren und sie gegebenenfalls über einen noch längeren Zeitraum als in dieser Studie zu untersuchen.
- Published
- 2023
- Full Text
- View/download PDF
14. Influence of leptin and compression in GAS-6 mediated homeostasis of periodontal ligament cell
- Author
-
Yong, Jiawen, Groeger, Sabine Elisabeth, Ruf, Sabine, Ruiz-Heiland, Gisela, and Justus Liebig University Giessen
- Subjects
ddc:610 - Published
- 2023
- Full Text
- View/download PDF
15. Value of Right and Left Ventricular T1 and T2 Blood Pool Mapping in Patients with Chronic Thromboembolic Hypertension before and after Balloon Pulmonary Angioplasty
- Author
-
Roller, Fritz C., Schüßler, Armin, Kremer, Nils, Harth, Sebastian, Kriechbaum, Steffen D., Wiedenroth, Christoph B., Guth, Stefan, Breithecker, Andreas, Richter, Manuel, Tello, Khodr, Seeger, Werner, Mayer, Eckhard, Krombach, Gabriele A., and Justus Liebig University Giessen
- Subjects
T2 mapping ,ddc:610 ,CTEPH ,parametric imaging ,CMR ,T1 mapping - Abstract
Background: Parametric imaging has taken a steep rise in recent years and non-cardiac applications are of increasing interest. Therefore, the aim of our study was to assess right (RV) and left ventricular (LV) blood pool T1 and T2 values in patients with chronic thromboembolic pulmonary hypertension (CTEPH) compared to control subjects and their correlation to pulmonary hemodynamic. Methods: 26 patients with CTEPH (mean age 64.8 years ± 12.8 SD; 15 female), who underwent CMR and right heart catheterization (RHC) before and 6-months after balloon pulmonary angioplasty (BPA), were retrospectively included. Ventricular blood pool values were measured, compared to control subjects (mean age 40.5 years ± 12.8 SD; 16 female) and correlated to invasive measures (CI, mPAP, PVR). Results: In both, control subjects and CTEPH patients, RVT1 and RVT2 were significantly reduced compared to LVT1 and LVT2. Compared to control subjects, RVT2 was significantly reduced in CTEPH patients (p = 0.0065) and increased significantly after BPA (p = 0.0048). Moreover, RVT2 was positively correlated with CI and negatively correlated with mPAP and PVR before (r = 0.5155, r = −0.2541, r = −0.4571) and after BPA (r = 0.4769, r = −0.2585, r = −0.4396). Conclusion: Ventricular blood pool T2 mapping might be novel non-invasive CMR imaging marker for assessment of disease severity, prognosis, follow-up and even therapy monitoring in PH.
- Published
- 2023
- Full Text
- View/download PDF
16. Regulation of the unfolded protein response, endoplasmic reticulum stress and autophagy pathways in the host response to coronavirus infection
- Author
-
Shikh Shaban, M.Samer and Justus Liebig University Giessen
- Subjects
MERS-CoV ,ddc:610 ,ER ,SARS-CoV-2 ,CoV ,thapsigargin ,Autophagy ,HCoV-229E ,UPR ,ddc:570 - Abstract
Coronaviruses (CoV) are a group of RNA viruses that have continuously posed risks to humans’ health and economy. Since the first recorded major CoV outbreak of SARS-CoV in 2001, using modern scientific methods, tremendous effort and resources have been devoted to better understanding the transmission of these viruses to humans and the associated disease manifestations. Like all known viruses, CoV require and utilize intracellular signaling pathways to replicate in the host cell. In doing so, CoV have apparently evolved diverse strategies to modulate these systems to initiate the formation of novel pathogenic intracellular structures, including so-called double membrane vesicles (DMVs), which collectively have been termed replicative organelles (ROs). DMVs and ROs are essential for successful CoV replication. Their formation, together with massively increased synthesis of viral protein and RNA components, leads to pronounced activation of affected cells. Among the cellular processes modulated early and most strongly during CoV infection are those related to the endoplasmic reticulum (ER) stress response and autophagy. Activation of ER signaling pathways by CoV results in ER stress and triggering of the unfolded protein response (UPR). The UPR is an adaptive process by which the cell attempts to restore normal ER function through activation of protein kinases, transcription factors, and downstream genetic programs. This involves a number of well-characterized molecular sensor and effector molecules anchored in the ER membrane, which include the protein kinases PERK and IRE1α and the chaperone BiP (GRP78, HSPA5). Autophagy refers to a highly dynamic process by which the cell can degrade larger molecular complexes, organelles, or invading pathogens and recycle or destroy the resulting macromolecules. As part of the autophagy process, a double membrane structure (the autophagosome) is formed, which interacts with the proteins LC3B and p62/SQSTM1 (sequestosome1) to coordinate basal, as well as selective, autophagy flux in response to various stressors, including viral infections. In this work, the central questions were investigated to what extent (i) CoV specifically modulate the ER stress and autophagy system and whether (ii) new starting points for antiviral strategies can be derived from this. To this end, a series of specific molecular but also proteome-wide analyses were performed in pharmacologically and genetically perturbed cellular model systems. Small molecule inhibitors were used to examine the effect of inhibiting PERK, IRE1α, or both protein kinases on CoV replication as well as on activation of the UPR and host response. One of the major findings of this approach was that inhibition of PERK resulted in a reduction in replication of HCoV-229E and MERS-CoV, but not SARS-CoV-2. HCoV-229E infection of Huh7 cells resulted in induction of the transcription factor ATF3 and suppression of BiP. PERK inhibition abolished both of these effects and led to a reduction in phosphorylation of serine 52 of the translation-inhibitory factor eIF2α. In contrast, inhibition of IRE1α resulted in only a small reduction in HCoV-229E replication but completely prevented virus-induced ATF3 induction. Arteficial, "chemical" activation of the UPR by the natural product thapsigargin resulted in strong inhibition of replication of all three CoV tested with a half-maximal effective concentration (EC50) in the low nanomolar range with concomitant low cytotoxicity. Furthermore, thapsigargin treatment of CoV-infected cells was associated with partial abrogation of global HCoV-229E-induced inhibition of protein biosynthesis and resulted in almost complete inhibition of CoV-induced selective and basal autophagy flux. Subsequently, a genetic approach based on the CRISPR-CAS-9 system was used to further investigate the roles of PERK, IRE1α, and ATF3 in CoV replication. Silencing of PERK resulted in a decrease in HCoV-229E replication, whereas suppression of IRE1α or ATF3 showed very little or no effect on virus replication. In addition, mass spectrometric techniques were used to comparatively examine changes in the proteome in CoV-infected and thapsigargin-treated cells. Bioinformatic analyses of the differentially expressed proteins resulted in the identification of a number of specific metabolic processes, signaling pathways, and factors that may be responsible for the antiviral effect of thapsigargin, including ER-associated degradation (ERAD) and ER quality control (ERQC) pathways. In the final part of the work, a proximity-based, proteome-wide interaction screen was performed to reveal the intracellular binding partners of ATF3 in the context of HCoV-229E infection. This led to the identification of a number of components of the immune system and mitochondrial homeostasis that are potential ATF3-dependent regulated effector molecules. In summary, the results obtained in this work provide insight into the CoV-specific activation patterns of the ER stress factors PERK, IRE1α, BiP, and ATF3 and their role in CoV replication and host response. The extensive evidence for antiviral efficacy of thapsigargin establishes chemical activation of the ER stress system as a novel antiviral therapeutic principle against enveloped RNA viruses such as HCoV-229E, MERS-CoV, and SARS-CoV-2 and identifies thapsigargin as a new prototype of compounds with multimodal host-directed antiviral activity based on molecular mechanisms of action.
- Published
- 2023
- Full Text
- View/download PDF
17. Prehospital emergency medicine for children receiving palliative home care in Germany—a cross-sectional, exploratory study of EMS providers
- Author
-
Hauch, Holger, El Mohaui, Naual, Vaillant, Vera, Sander, Michael, Kriwy, Peter, Rohde, Marius, Wolff, Johannes, Berthold, Daniel, Schneck, Emmanuel, and Justus Liebig University Giessen
- Subjects
do-not-resuscitate order ,ddc:610 ,emergency medical service ,palliative home care ,pediatric emergencies ,cardiopulmonary resuscitation - Abstract
Background: The prevalence of children with life-limiting conditions is rising, and since the amendment of the social insurance code in Germany, palliative home care teams have treated an increasing number of children. These teams provide 24/7 readiness, yet some parents still call the general emergency medical service (EMS) for various reasons. EMS is exposed to complex medical problems in rare diseases. Questions arose about the experiences of EMS and whether they felt prepared for emergencies involving children treated by a palliative care team. Methods: This study used a mixed methods approach to focus on the interface between palliative care and EMS. First, open interviews were conducted, and a questionnaire was developed based on the results. The variables included demographic items and individual experiences with patients. Second, a case report of a child with respiratory insufficiency was presented to assess the spontaneous treatment intentions of EMS providers. Finally, the need, relevant topics, and duration of specific training in palliative care for EMS providers were evaluated. Results: In total, 1,005 EMS providers responded to the questionnaire. The average age was 34.5 years (±10.94SD), 74.6% were male. The average work experience was 11.8 years (±9.7), 21.4% were medical doctors. Experience with a call of a life-threatening emergency involving a child was reported by 61.5% and severe psychological distress during such a call was reported by 60.4%. The equivalent distress frequency for adult patient calls was 38.3%. (p < 0.001). After review of the case report, the EMS respondents suggested invasive treatment options and rapid transport to the hospital. Most (93.7%) respondents welcomed the consideration of special training in pediatric palliative care. This training should include basic information about palliative care, an analysis of cases involving palliatively treated children, an ethical perspective, practical recommendations, and available (24/7) local contact for further guidance and support. Conclusion: Emergencies in pediatric palliatively treated patients were more common than expected. EMS providers perceived the situations as stressful, and there is a need for specific training with practical aspects.
- Published
- 2023
- Full Text
- View/download PDF
18. Impaired self-awareness of cognitive deficits in Parkinson's disease relates to cingulate cortex dysfunction
- Author
-
Maier, Franziska, Greuel, Andrea, Hoock, Marius, Kaur, Rajbir, Tahmasian, Masoud, Schwartz, Frank, Csoti, Ilona, Jessen, Frank, Drzezga, Alexander, van Eimeren, Thilo, Timmermann, Lars, Eggers, Carsten, and Justus Liebig University Giessen
- Subjects
ddc:610 - Published
- 2023
- Full Text
- View/download PDF
19. Importance of Mitochondria in Cardiac Pathologies: Focus on Uncoupling Proteins and Monoamine Oxidases
- Author
-
Schulz, Rainer, Schlüter, Klaus-Dieter, and Justus Liebig University Giessen
- Subjects
reactive oxygen species ,ddc:610 ,pulmonary hypertension ,heart failure ,ischemia ,reperfusion - Abstract
On the one hand, reactive oxygen species (ROS) are involved in the onset and progression of a wide array of diseases. On the other hand, these are a part of signaling pathways related to cell metabolism, growth and survival. While ROS are produced at various cellular sites, in cardiomyocytes the largest amount of ROS is generated by mitochondria. Apart from the electron transport chain and various other proteins, uncoupling protein (UCP) and monoamine oxidases (MAO) have been proposed to modify mitochondrial ROS formation. Here, we review the recent information on UCP and MAO in cardiac injuries induced by ischemia-reperfusion (I/R) as well as protection from I/R and heart failure secondary to I/R injury or pressure overload. The current data in the literature suggest that I/R will preferentially upregulate UCP2 in cardiac tissue but not UCP3. Studies addressing the consequences of such induction are currently inconclusive because the precise function of UCP2 in cardiac tissue is not well understood, and tissue- and species-specific aspects complicate the situation. In general, UCP2 may reduce oxidative stress by mild uncoupling and both UCP2 and UCP3 affect substrate utilization in cardiac tissue, thereby modifying post-ischemic remodeling. MAOs are important for the physiological regulation of substrate concentrations. Upon increased expression and or activity of MAOs, however, the increased production of ROS and reactive aldehydes contribute to cardiac alterations such as hypertrophy, inflammation, irreversible cardiomyocyte injury, and failure.
- Published
- 2023
- Full Text
- View/download PDF
20. Activation of endothelial NO synthase and P2X7 receptor modification mediates the cholinergic control of ATP-induced interleukin-1ß release by mononuclear phagocytes
- Author
-
Richter, Katrin, Asci, Nilay, Singh, Vijay K., Yakoob, Sanaria Hawro, Meixner, Marion, Zakrzewicz, Anna, Liese, Juliane, Hecker, Andreas, Wilker, Sigrid, Stumpf, Sabine, Schlüter, Klaus-Dieter, Rohde, Marius, Gödecke, Axel, Padberg, Winfried, Manzini, Ivan, Schmalzing, Günther, Grau, Veronika, and Justus Liebig University Giessen
- Subjects
ddc:610 ,inflammation ,P2X7 receptor ,endothelial NO synthase ,CHRNA7 ,CHRNA9 ,monocytes ,CHRNA10 ,macrophages - Abstract
Objective: The pro-inflammatory cytokine interleukin-1β (IL-1β) plays a central role in host defense against infections. High systemic IL-1β levels, however, promote the pathogenesis of inflammatory disorders. Therefore, mechanisms controlling IL-1β release are of substantial clinical interest. Recently, we identified a cholinergic mechanism inhibiting the ATP-mediated IL-1β release by human monocytes via nicotinic acetylcholine receptor (nAChR) subunits α7, α9 and/or α10. We also discovered novel nAChR agonists that trigger this inhibitory function in monocytic cells without eliciting ionotropic functions at conventional nAChRs. Here, we investigate the ion flux-independent signaling pathway that links nAChR activation to the inhibition of the ATP-sensitive P2X7 receptor (P2X7R). Methods: Different human and murine mononuclear phagocytes were primed with lipopolysaccharide and stimulated with the P2X7R agonist BzATP in the presence or absence of nAChR agonists, endothelial NO synthase (eNOS) inhibitors, and NO donors. IL-1β was measured in cell culture supernatants. Patch-clamp and intracellular Ca2+ imaging experiments were performed on HEK cells overexpressing human P2X7R or P2X7R with point mutations at cysteine residues in the cytoplasmic C-terminal domain. Results: The inhibitory effect of nAChR agonists on the BzATP-induced IL-1β release was reversed in the presence of eNOS inhibitors (L-NIO, L-NAME) as well as in U937 cells after silencing of eNOS expression. In peripheral blood mononuclear leukocytes from eNOS gene-deficient mice, the inhibitory effect of nAChR agonists was absent, suggesting that nAChRs signal via eNOS to inhibit the BzATP-induced IL-1β release. Moreover, NO donors (SNAP, S-nitroso-N-acetyl-DL-penicillamine; SIN-1) inhibited the BzATP-induced IL-1β release by mononuclear phagocytes. The BzATP-induced ionotropic activity of the P2X7R was abolished in the presence of SIN-1 in both, Xenopus laevis oocytes and HEK cells over-expressing the human P2X7R. This inhibitory effect of SIN-1 was absent in HEK cells expressing P2X7R, in which C377 was mutated to alanine, indicating the importance of C377 for the regulation of the P2X7R function by protein modification. Conclusion: We provide first evidence that ion flux-independent, metabotropic signaling of monocytic nAChRs involves eNOS activation and P2X7R modification, resulting in an inhibition of ATP signaling and ATP-mediated IL-1β release. This signaling pathway might be an interesting target for the treatment of inflammatory disorders.
- Published
- 2023
- Full Text
- View/download PDF
21. Entwicklung des Erregerspektrums, der Antibiotikaresistenz und des Antibiotikaverbrauches einer urologischen Universitätsklinik
- Author
-
Reiser, Leo Thomas and Justus Liebig University Giessen
- Subjects
ddc:610 - Abstract
Wir analysierten das Erregerspektrum und die bakterielle Resistenzentwicklung der urologischen Klinik des Universitätsklinikums Gießen zusammen mit dem dazugehörigen Antibiotikaverbrauch im stationären Bereich. Der Antibiotikaverbrauch in beiden Datensätzen zeigte keinen signifikanten Verbrauchsanstieg. 2010-2017 konnte ein Rückgang der Antibiotikaverbrauchsdichte nachgewiesen werden. Damit kann der in der GERMAP2015 beschriebene Trend eines deutschlandweiten steigenden Antibiotikaverbrauch durch die Verbrauchsdaten der Urologie in Gießen nicht bestätigt werden. Es zeigte sich ein klarer Trend zu mehr parenteral eingesetzten Antibiotika. 1992-2008 kam es zu einem deutlichen Anstieg des Cephalosporin- und Fluorchinolon-Verbrauchs, welcher sich im Gesamtverbrauch von 2010-2017 zeigt, wo diese beiden Antibiotikagruppen 76% des Verbrauchs ausmachen. Ab 2010 kam es zu einem Rückgang der Verordnungen an Cephalosporinen, Fluorchinolonen und Penicillinen. Im nationalen Vergleich ist die Antibiotikaverbrauchsdichte im Jahr 2017 um ein Viertel niedriger als der, der Referenzgruppe des AVS. Es wurden deutlich weniger Cephalosporine und Penicilline eingesetzt. 25.844 Keime wurden in die Erregerstatistik eingeschlossen. E.coli (33%), E.faecalis (22%), Klebsiella spp. (10%) und Pseudomonas spp. (7%) machten den Hauptanteil des Keimspektrums aus. Das Keimspektrum zeigt eher einen niedrigen Anteil von E.coli, dafür einen höheren Anteil an Enterokokken. Die Anzahl der nachgewiesenen Erreger/100 Patienten war zwischen 2005 und 2017 signifikant rückläufig. Bei E.coli war bei der Ampicillin/Sulbactam, Ciprofloxacin und Gentamicin-Resistenz ein Anstieg zu beobachten. Einen Rückgang des Resistenzniveaus zeigte sich bei Piperacillin/Tazobactam. Klebsiella spp. zeigte eine Zunahme unter anderem bei Piperacillin/Tazobactam und eine Abnahme bei Trimethoprim/Sulfamethoxazol. S. aureus verzeichnete bei vielen Antibiotika einen Rückgang des Resistenzniveaus. Ebenfalls rückläufig war der Anteil an MRSA. Dieser Trend wird durch zahlreiche nationale und internationale Surveillance-Systeme bestätigt. Der Anteil an multiresistenten Erregern wie ESBL und 3MRGN insbesondere bei E.coli und Proteus spp. nimmt zu. 4MRGN kommen jedoch nur vereinzelt vor. Bei E.faecium steigt die Rate an VRE.
- Published
- 2023
- Full Text
- View/download PDF
22. The Type III Transforming Growth Factor-β receptor (Betaglycan or BG) Modulates TGF-β Signaling and Wound Healing in Human Endometrial Cells and in Endometriosis
- Author
-
Mwaura, Agnes Njoki and Justus Liebig University Giessen
- Subjects
SMAD2/3 ,ddc:610 ,Endometriosis ,Betaglycan ,TGF-beta ,Activin A - Abstract
Endometriosis is an estrogen-responsive disease defined as the presence of endometrial tissue at ectopic sites. TGF-β superfamily members are pleiotropic cytokines that exhibit cell-type-specific effects and regulate a plethora of diverse cellular responses. Perturbations in TGF-β superfamily components and signaling have been implicated in endometriosis. Betaglycan (BG) is a vital co-receptor and modulator of TGF-β superfamily. It functions as a tumor suppressor in numerous cancers. In the current investigation, we addressed the modulation of BG shedding by TGF-β, activin A and inhibin A and the molecular mechanisms involved using endometrial in vitro models. We also analyzed the influence of TGF-βs and BG on wound healing in endometriotic cells. Additionally, we investigated the utility of serum/endocervical mucus sBG and ADAM12 levels as potential non-invasive diagnostic biomarkers for endometriosis. The results demonstrated that TGF-β1/2 and activin A suppress shedding of BG via the ALK-4/5–SMAD3 axis in human endometriotic cells. We observed that inhibin A also suppresses BG shedding. Notably, shedding was modulated by MMPs. Furthermore, recombinant BG significantly reduced secretion of TGF-β1/2 and the rate of wound closure in endometriotic cells but had no influence on their viability. Interestingly, TGF-β1 significantly augmented secretion of MMP2/3 and enhanced the rate of wound closure in endometriotic cells. Conversely, TGF-β2 promoted secretion of MMP2 only and had no effect on the rate of wound closure. Activin A but not inhibin A significantly enhanced secretion of MMP2/3. Remarkably, endocervical mucus but not serum sBG levels were significantly reduced in endometriosis patients compared to controls. TGF-β1/2 significantly augmented secretion of ADAM12 in endometrial stromal cells in vitro. ADAM12 localizes mainly to the luminal and glandular epithelial cells as well as smooth muscle cells of eutopic and ectopic endometrium. No significant differences were observed in ADAM12 levels in endometrial staining intensity as well as in serum/endocervical mucus samples from endometriosis patients relative to controls. These findings provide new insights into the roles of BG in TGF-β signaling, wound healing, and in the pathophysiology of endometriosis. The strong reduction in BG shedding indicates that the TGF-β ligands require mBG for signaling, since it is particularly vital in establishing the potency of its ligands on their target cells. We speculate that the reduced endocervical mucus sBG levels in endometriosis patients may indicate enhanced TGF-β functions, which may in part be linked to the chronic inflammation observed in endometriosis. Although speculative, we propose that sBG may represent a potential therapeutic agent and an early diagnostic biomarker and hence, further studies to elucidate its function in endometriosis will undoubtedly provide indispensable insights.
- Published
- 2023
- Full Text
- View/download PDF
23. Inhibition of Transglutaminase 2 as a Therapeutic Strategy in Celiac Disease - In Vitro Studies in Intestinal Cells and Duodenal Biopsies
- Author
-
Stricker, Sebastian, de Laffolie, Jan, Zimmer, Klaus-Peter, Rudloff, Silvia, and Justus Liebig University Giessen
- Subjects
ddc:610 ,PX-12 ,gliadin transport ,TG2 inhibitor ,transglutaminase 2 ,celiac disease - Abstract
Enzymatic modification of gliadin peptides by human transglutaminase 2 (TG2) is a key mechanism in the pathogenesis of celiac disease (CD) and represents a potential therapeutic target. Recently, we have identified the small oxidative molecule PX-12 as an effective inhibitor of TG2 in vitro. In this study, we further investigated the effect of PX-12 and the established active-site directed inhibitor ERW1041 on TG2 activity and epithelial transport of gliadin peptides. We analyzed TG2 activity using immobilized TG2, Caco-2 cell lysates, confluent Caco-2 cell monolayers and duodenal biopsies from CD patients. TG2-mediated cross-linking of pepsin-/trypsin-digested gliadin (PTG) and 5BP (5-biotinamidopentylamine) was quantified by colorimetry, fluorometry and confocal microscopy. Cell viability was tested with a resazurin-based fluorometric assay. Epithelial transport of promofluor-conjugated gliadin peptides P31-43 and P56-88 was analyzed by fluorometry and confocal microscopy. PX-12 reduced TG2-mediated cross-linking of PTG and was significantly more effective than ERW1041 (10 µM, 15 ± 3 vs. 48 ± 8%, p < 0.001). In addition, PX-12 inhibited TG2 in cell lysates obtained from Caco-2 cells more than ERW1041 (10 µM; 12 ± 7% vs. 45 ± 19%, p < 0.05). Both substances inhibited TG2 comparably in the intestinal lamina propria of duodenal biopsies (100 µM, 25 ± 13% vs. 22 ± 11%). However, PX-12 did not inhibit TG2 in confluent Caco-2 cells, whereas ERW1041 showed a dose-dependent effect. Similarly, epithelial transport of P56-88 was inhibited by ERW1041, but not by PX-12. Cell viability was not negatively affected by either substance at concentrations up to 100 µM. PX-12 did not reduce TG2 activity or gliadin peptide transport in confluent Caco-2 cells. This could be caused by rapid inactivation or degradation of the substance in the Caco-2 cell culture. Still, our in vitro data underline the potential of the oxidative inhibition of TG2. The fact that the TG2-specific inhibitor ERW1041 reduced the epithelial uptake of P56-88 in Caco-2 cells further strengthens the therapeutic potential of TG2 inhibitors in CD.
- Published
- 2023
- Full Text
- View/download PDF
24. Investigation of the role of CCR2 and activin A in fibrosis development during experimental autoimmune orchitis
- Author
-
Peng, Wei and Justus Liebig University Giessen
- Subjects
ddc:610 - Abstract
EAO is a mouse model of chronic testicular inflammation and fibrosis, well reflecting pathologies seen in some forms of spermatogenic disturbances in men. This model is characterized by the destruction of testicular morphology, infiltration of the testicular interstitium by leukocytes, elevated levels of pro-inflammatory cytokines/ chemokines such as TNF, CCL2 (ligand for CCR2) and activin A, as well as loss of germ cells, all leading to fibrosis and subsequent infertility. TMs constitute the principal immune cell population in the testis and these cells play a critical role in maintaining tissue homeostasis. Increased numbers of TMs during testicular inflammation correlate with a higher incidence and severity of testicular damage. Because resident or macrophages newly recruited to the inflammatory lesions can produce a variety of pro-fibrotic factors including CCL2, TGF-β, TNF, PDGFs, MMPs or TIMPs, they are key players in fibrotic remodeling. CCL2 and CCR2 have a critical role in mediating the trafficking of monocytes, macrophages or bone marrow-derived fibroblasts to the site of injury. In the EAO model, an increase of CCL2 is observed not only in the testicular tissue but also in testicular interstitial fluid and conditioned medium from cultured TMs. Furthermore, activin A, a member of the TGF-β superfamily of cytokines, released mainly by SCs is increased in EAO testis and levels correlate with the severity of disease. Activin A stimulates resting macrophages to produce inflammatory mediators and promotes the expression of fibrosis specific genes in PTCs and NIH 3T3 fibroblasts in vitro. Based on these findings, we hypothesize that activin A in concert with CCR2 influences the development of testicular fibrosis by regulating the properties of macrophages, which in turn are an important source of pro-fibrotic factors in EAO. Therefore, the aims of this study are (1) to investigate the effect of CCR2 on the development of fibrosis during testicular inflammation, and (2) to analyze the influence of activin A on the fibrotic response in macrophages.
- Published
- 2023
- Full Text
- View/download PDF
25. What to Prefer in Patients with Multibracket Appliances? Digital vs. Conventional Full-Arch Impressions - A Reference Aid-Based In Vivo Study
- Author
-
Bock, Niko Christian, Klaus, Katharina, Liebel, Moritz Maximilian, Ruf, Sabine, Wöstmann, Bernd, Schlenz, Maximiliane Amelie, and Justus Liebig University Giessen
- Subjects
ddc:610 ,accuracy ,trueness ,alginate ,precision ,intraoral scanner ,clinical study ,reference ,full-arch impression ,multibracket appliance ,digital dentistry - Abstract
This study aimed to investigate the transfer accuracy and required time for digital full-arch impressions obtained from intraoral scanners (IOSs) versus conventional alginate impressions (CAIs) in patients with multibracket appliances (MBA). Thirty patients with buccal MBAs (metal brackets, archwire removed) were examined using an established reference aid method. Impression-taking using four IOSs (Primescan, Trios 4, Medit i700, Emerald S) and one CAI with subsequent plaster casting were conducted. One-hundred-twenty (n = 30 x 4) scans were analyzed with 3D software (GOM Inspect) and 30 (n = 30 x 1) casts were assessed using a coordinate measurement machine. Six distances and six angles were measured and compared to the reference aid values (ANOVA; p < 0.05). Except for the intermolar distance, transfer accuracy was significantly higher with IOSs than with CAIs (p < 0.05). No such difference was found regarding the six angles. In patients with MBAs, digital impression-taking using IOSs can be recommended. For all measured variables except one, the transfer accuracy of IOSs was better than or at least equivalent to the data from CAIs. In addition, significantly (p < 0.001) less time was necessary for all IOSs in comparison to CAIs plus plaster casting.
- Published
- 2023
- Full Text
- View/download PDF
26. Metabolic reprogramming of hepatocytes by Schistosoma mansoni eggs
- Author
-
von Bülow, Verena, Gindner, Sarah, Baier, Anne, Hehr, Laura, Buss, Nicola, Russ, Lena, Wrobel, Sarah, Wirth, Victoria, Tabatabai, Kuscha, Quack, Thomas, Haeberlein, Simone, Kadesch, Patrik, Gerbig, Stefanie, Wiedemann, Katja R., Spengler, Bernhard, Mehl, Annabel, Morlock, Gertrud, Schramm, Gabriele, Pons-Kühnemann, Jörn, Falcone, Franco H., Wilson, R. Alan, Bankov, Katrin, Wild, Peter, Grevelding, Christoph G., Roeb, Elke, Roderfeld, Martin, and Justus Liebig University Giessen
- Subjects
Parasite ,ddc:610 ,Oxidative stress ,Schistosomiasis ,DNA damage ,Lipid - Abstract
Background & Aims: Schistosomiasis is a parasitic infection which affects more than 200 million people globally. Schistosome eggs, but not the adult worms, are mainly responsible for schistosomiasis-specific morbidity in the liver. It is unclear if S. mansoni eggs consume host metabolites, and how this compromises the host parenchyma. Methods: Metabolic reprogramming was analyzed by matrix-assisted laser desorption/ionization mass spectrometry imaging, liquid chromatography with high-resolution mass spectrometry, metabolite quantification, confocal laser scanning microscopy, live cell imaging, quantitative real-time PCR, western blotting, assessment of DNA damage, and immunohistology in hamster models and functional experiments in human cell lines. Major results were validated in human biopsies. Results: The infection with S. mansoni provokes hepatic exhaustion of neutral lipids and glycogen. Furthermore, the distribution of distinct lipid species and the regulation of rate-limiting metabolic enzymes is disrupted in the liver of S. mansoni infected animals. Notably, eggs mobilize, incorporate, and store host lipids, while the associated metabolic reprogramming causes oxidative stress-induced DNA damage in hepatocytes. Administration of reactive oxygen species scavengers ameliorates these deleterious effects. Conclusions: Our findings indicate that S. mansoni eggs completely reprogram lipid and carbohydrate metabolism via soluble factors, which results in oxidative stress-induced cell damage in the host parenchyma. Impact and implications: The authors demonstrate that soluble egg products of the parasite S. mansoni induce hepatocellular reprogramming, causing metabolic exhaustion and a strong redox imbalance. Notably, eggs mobilize, incorporate, and store host lipids, while the metabolic reprogramming causes oxidative stress-induced DNA damage in hepatocytes, independent of the host’s immune response. S. mansoni eggs take advantage of the host environment through metabolic reprogramming of hepatocytes and enterocytes. By inducing DNA damage, this neglected tropical disease might promote hepatocellular damage and thus influence international health efforts.
- Published
- 2023
- Full Text
- View/download PDF
27. Analyse von Initialwerten und Verlaufskurven von Serum Amyloid A-Konzentrationen im Blut bei Pferden mit akuten Gliedmaßenverletzungen und Beteiligung synovialer Strukturen
- Author
-
Müller, Anke-Charlotte and Justus Liebig University Giessen
- Subjects
Krankheitsüberwachung ,ddc:500 ,ddc:610 ,Diagnose ,Verletzung ,Wunde ,ddc:630 ,ddc:590 ,Serum Amyloid A ,Gelenk ,Pferd ,Entzündungsparameter ,Synoviale Struktur - Abstract
Akute Riss-, Quetsch- oder Schnittverletzungen an Gliedmaßen mit Beteiligung synovialer Strukturen stellen einen häufigen Notfall in der Pferdepraxis dar und können zur vollständigen Restriktion der sportlichen Aktivität betroffener Pferde führen. Daher sind eine präzise und schnelle Diagnose sowie eine gründliche postoperative Überwachung von entscheidender Bedeutung, um eine optimale Prognose zu gewährleisten. Der Nachweis der Beteiligung einer synovialen Struktur kann jedoch herausfordernd sein, wenn die herkömmlichen diagnostischen Mittel wie klinische Parameter oder die Werte der Synoviauntersuchung nicht schlüssig sind bzw. kein eindeutiges Ergebnis liefern. Auch die frühzeitige Erkennung eines Wiederaufflammens der Infektion innerhalb der betroffenen synovialen Struktur im Rahmen der postoperativen Überwachung ist unerlässlich, um eine folgenreiche Schädigung der betroffenen Struktur zu vermeiden. Als Reaktion auf die synoviale Kontamination ist die systemische Akute Phase Reaktion der erste Mechanismus zur Kontrolle einer synovialen Infektion. Serum-Amyloid A (SAA), das wichtigste Akute-Phase-Protein bei Pferden, hat sich bereits als hilfreiches Instrument in der postoperativen Überwachung nach elektiven Eingriffen erwiesen. Die Bewertung der systemischen Entzündungsreaktion anhand einer SAA-Messung kann zur Beurteilung der lokalen Situation innerhalb der synovialen Struktur herangezogen werden. Ein zentraler Punkt in der Therapie synovialer Infektionen ist eine systemische antibiotische Therapie. Die Dauer der postoperativen systemischen Behandlung mit Antibiotika ist bislang jedoch nicht standardisiert. In dieser Studie wurde der Wert von SAA im Rahmen der initialen Diagnose und der postoperativen Überwachung von Pferden mit Beteiligung von synovialen Strukturen aufgrund akuter (30 x 109 Zellen/L; Anteil der neutrophilen Granulozyten, %N >90 %; Gesamtprotein, TP >25 g/L), der Detektion einer Verbindung zwischen Wunde und synovialer Struktur mittels Ballonierung des Gelenks, Röntgenaufnahmen und/oder einer Ultraschalluntersuchung, wobei die Ergebnisse in Korrelation interpretiert wurden. SAA wurde im Serum initial bei Vorstellung des Patienten (vor der chirurgischen Versorgung) und folgend 12 Stunden, 24 Stunden und 48 Stunden nach Erstvorstellung des Patienten sowie anschließend alle 48 Stunden gemessen, bis physiologische Referenzwerte erreicht wurden. Im Rahmen der Eingangsdiagnostik wurden das Allgemeinbefinden und der Lahmheitsgrad bewertet sowie die Herzfrequenz und die Rektaltemperatur gemessen. Zusätzlich wurden Leukozyten und Fibrinogen im Blut bestimmt. Außerdem wurde eine Synoviauntersuchung mit Bestimmung der Parameter Makroskopie, TNCC, % N und TP durchgeführt. Im folgenden Verfahren wurden der Lahmheitsgrad und die Körpertemperatur täglich erhoben. SAA wurde zwischen den beiden Gruppen verglichen und mit klinischen Parametern, Blutparametern und Parametern der Synoviauntersuchung korreliert. Darüber hinaus wurde das Long-term Outcome ermittelt und entsprechend dem Leistungsniveau jedes Pferdes zwei Jahre nach der Entlassung in Kategorien eingeteilt. Ein P-Wert
- Published
- 2023
- Full Text
- View/download PDF
28. Etablierung und Validierung eines Reportersystems zur Identifikation von mikro-homologer DNA-Rekombination
- Author
-
Gambert, Isabel Sophia and Justus Liebig University Giessen
- Subjects
Retinitis pigmentosa ,XLRP ,Gentherapie ,microhomology-mediated end-joining ,ddc:610 ,mikrohomologe DNA-Rekombination ,Medizin ,MMEJ ,RPGR ,Genome editing - Abstract
Die X-chromosomale Form der Retinitis pigmentosa (XLRP) stellt aufgrund der progredienten Degeneration der Photorezeptoren mit Erblindung innerhalb der zweiten Lebensdekade eine der schwerwiegenderen Formen der RP dar und ist aktuell nicht heilbar. 80 % der die XLRP verursachenden Mutationen sind im terminalen Exon des RPGR-Gens (Retinitis pigmentosa GTPase regulator), der ORF15-Region, lokalisiert, weshalb die Korrektur der mutierten Gensequenz durch Genome Editing einen kurativen Therapieansatz bietet. Der körpereigene DNA-DSB-Reparaturmechanismus MMEJ (microhomology mediated end-joining) ist in Kombination mit hochspezifischen Endonukleasen wie CRISPR/Cas9 eine Alternative zu den bereits im Genome Editing eingesetzten HR (homologous recombination) und NHEJ (non-homologous end joining). Das Ziel dieser Doktorarbeit war die Etablierung eines Reportersystem in vitro zur Testung und Effizienzsteigerung von MMEJ, das durch den Einsatz in der ORF15-Region des RPGR-Genlokus einen kurativen Therapieansatz für die XLRP bietet. Es erfolgte die Generierung eines auf Fluoreszenz-basierenden Reportersystem für MMEJ zur Testung in HEK293-Zellen, die die RPGR-ORF15 Sequenz mit einem vorgeschalteten CMV-Promoter enthalten. Über mikrohomologe DNA-Rekombination, induziert durch das gezielte Einbringen von DSB durch CRISPR/Cas9, kann die Luziferase-Gensequenz flankiert von mikrohomologen Sequenzen (mhS), die komplementär zur RPGR-ORF15 Region sind, in das Genom integriert und durch den CMV-Promoter exprimiert werden. Es erfolgte die Messung der Luziferase-Aktivität unter Variation der Länge der mhS (10, 15, 20 und 30 bp). In dieser Arbeit konnte gezeigt werden, dass das Reportersystem ein wertvolles Werkzeug zur Etablierung und Validierung der Aktivität des DSB-Reparaturmechanismus MMEJ ist. Die geringere Signalaktivität bei Suppression der Ligase 3 (Schlüsselprotein von MMEJ) zeigt, das MMEJ durch das Reportersystem induziert wird. Unter Variation der Längen der mhS fand sich die höchste Luziferase-Aktivität bei 15 bp langen mhS. Durch die gezielte Suppression der konkurrierenden DSB-Reparaturmechanismen kann MMEJ favorisiert werden. Die effizienteste Suppression von NHEJ fand sich bei Knockdown der endständigen Ligase 4. Weiterführende Analysen der Knockdown-Strategien der konkurrierenden DSB-Reparaturmechanismen und die Evaluation des Reportersystems in in vivo Modellen sind erforderlich.
- Published
- 2023
- Full Text
- View/download PDF
29. Altered Posttranslational Modification of Microtubules Contributes to Disturbed Enterocyte Morphology in Celiac Disease
- Author
-
Stricker, Sebastian, Müller, Manuel, Zimmer, Klaus-Peter, Jacob, Ralf, and Justus Liebig University Giessen
- Subjects
microtubules ,ddc:610 ,tubulin tyrosine ligase ,detyrosinated tubulin ,vasohibin-2 ,celiac disease - Abstract
Celiac disease (CD) represents a frequent autoimmune disease triggered by the ingestion of gliadin in genetically predisposed individuals. The alteration of enterocytes and brush border membrane morphology have been repetitively demonstrated, but the underlying mechanisms remain unclear. Microtubules represent a major element of the cytoskeleton and exert multiple functions depending on their tyrosination status. The aim of our study was to investigate whether posttranslational modification of microtubules was altered in the context of CD and whether this mechanism contributed to morphological changes of CD enterocytes. We examined the expression of tubulin tyrosine ligase (TTL) and vasohibin-2 (VASH2) and the level of detyrosinated and acetylated tubulin in duodenal biopsies and Caco-2 cells by immunoblot and immunofluorescence microcopy. Electron microscopy was performed to investigate the subcellular distribution of detyrosinated tubulin and brush border membrane architecture in CD biopsies and Madin–Darby Canine Kidney type II (MDCK) cells lacking TTL. CD enterocytes and Caco-2 cells stimulated with digested gliadin or IFN-y displayed a flattened cell morphology. This disturbed cellular architecture was accompanied by an increased amount of detyrosinated and acetylated tubulin and corresponding high expression of VASH2 and low expression of TTL. The altered posttranslational modification of tubulin was reversible after the introduction of the gluten-free diet. CD enterocytes and MDCK cells deficient in TTL displayed a reduced cell height along with an increased cell width and a reduced number of apical microvilli. Our results provide a functional explanation for the observed morphological alterations of the enterocytes observed in CD and provide diagnostic potential of the tyrosination status of microtubules as an early marker of villous atrophy and CD inflammation.
- Published
- 2023
- Full Text
- View/download PDF
30. Is stress related to itch in German students? Results of an online survey
- Author
-
Kiupel, Stephanie, Kupfer, Jörg, Kottlors, Sophia, Gieler, Uwe, Yosipovitch, Gil, Schut, Christina, and Justus Liebig University Giessen
- Subjects
ddc:610 ,students ,perceived stress ,self report ,skin symptoms ,pruritus - Abstract
Introduction: German students report to be more stressed than the general population. Highly stressed students from other countries (United States, Australia, Saudi-Arabia) were found to have more skin symptoms, including itch, than lowly stressed students. The current study aimed to assess whether itch is associated with stress in a larger sample of German students. Methods: 838 students (3.2% of all invited students) took part in the questionnaire based study and filled in the Perceived Stress Questionnaire as well as a modified version of the Self-Reported Skin Questionnaire. Students were categorized into highly (HSS) and lowly stressed students (LSS) by determination of the 25th and 75th percentile. Results: Itch occurred significantly more often in HSS compared to LSS (OR = 3.41 (2.17–5.35)). In addition, itch intensity was significantly related to perceived stress. Discussion: These findings not only highlight the importance of offering stress management trainings also to students in Germany in order to minimize itch, but also encourage future research on stress and itch in certain student subgroups.
- Published
- 2023
- Full Text
- View/download PDF
31. Humoral and cellular immune responses to the mRNA-1273 SARS-CoV-2 vaccine booster in patients on maintenance dialysis
- Author
-
Karakizlis, Hristos, Agarwal, Vipul, Aly, Mostafa, Strecker, Kevin, Csala, Benjamin, Esso, Isla, Chen, Jiangping, Nahrgang, Christian, Wolter, Martin, Slanina, Heiko, Schüttler, Christian G., Jessen, Sönke, Ronco, Claudio, Seeger, Werner, Weimer, Rolf, Sester, Martina, Birk, Horst-Walter, Husain-Syed, Faeq, and Justus Liebig University Giessen
- Subjects
ddc:610 - Published
- 2023
- Full Text
- View/download PDF
32. Study protocol: Neuro-inflammatory parameters as mediators of the relationship between social anxiety and itch intensity: A cross-sectional, controlled laboratory study in patients with psoriasis and healthy skin controls
- Author
-
Schepko, Marcel, Stumpf, Katharina C., Tumala, Susanne, Peters, Eva M., Kupfer, Jörg P., Schut, Christina, and Justus Liebig University Giessen
- Subjects
ddc:610 - Abstract
Introduction Psoriasis (PSO) is a disease that in the majority of patients is accompanied by itch, which imposes a great burden and positively relates to anxiety. Social anxiety, a facet of anxiety associated with social withdrawal, may be a predictor of itch intensity in this patient group. Moreover, anxiety is linked to the secretion of neuroendocrine and inflammatory parameters such as substance P (SP), interleukin (IL)-6 and IL-17, which are also related to itch. In this research project, we investigate first, whether there is a direct relationship between social anxiety and itch intensity in patients with PSO and second whether the secretion of SP, IL-6 and IL-17 in the skin mediates this relationship. Additionally, PSO-patients are compared to healthy skin controls regarding their level of social anxiety, itch intensity and the secretion of SP, IL-6 and IL-17. Methods and analyses For study 1, we aim to recruit 250 psoriasis patients and 250 healthy skin controls who complete questionnaires to assess social anxiety, itch intensity and control variables (e.g. sociodemographic variables and severity of PSO). A linear hierarchic regression will be used to determine whether social anxiety significantly contributes to itch intensity. In study 2, we plan to apply the suction blister method to 128 patients and healthy skin controls recruited from study 1 to determine SP, IL-6 and IL-17 in tissue fluid extracted from the skin. A mediation analysis will be conducted using the SPSS-macro PROCESS to test whether the relationship between social anxiety and itch is mediated by SP, IL-6 and IL-17.
- Published
- 2023
- Full Text
- View/download PDF
33. Charakterisierung Hypoxie-induzierter pulmonalvaskulärer Veränderungen in adulten und fetalen Schafslungen
- Author
-
Uthayanan, Ushanthan and Justus Liebig University Giessen
- Subjects
ddc:610 ,Pulmonale Hypertonie des Neugeborenen ,PPHN ,Vitamin C ,Pulmonale Hypertonie - Abstract
Die persistierende pulmonale Hypertonie des Neugeborenen (PPHN) stellt eine schwerwiegende Lungenerkrankung des Neugeborenen dar. Dabei wird die chronische fetale Hypoxie als zweithäufigste Ursache aufgezählt, wobei dies nur unzureichend in den bisher etablierten Tiermodellen untersucht worden ist. Ziel dieser Arbeit war es demnach, durch chronische fetale Hypoxie induzierte pulmonalvaskuläre Veränderungen sowie deren mögliche Reversibilität durch Vitamin C zu charakterisieren. Anhand der Ergebnisse der vorliegenden Arbeit wird deutlich, dass eine chronische Hypoxie-Exposition im letzten Drittel der Schwangerschaft eine PPHN in fetalen Schafen induzierte. Diese PPHN persistierte auch nach der Geburt in adulten Schafen, die unter normoxischen Bedingungen aufwuchsen. Infolge der fetalen Hypoxie kam es zu einer Wandstärkenzunahme der Pulmonalgefäße. Vermutlich führt dies zu einem erhöhten pulmonal-arteriellen Widerstand mit einer Nachlasterhöhung im rechten Ventrikel. Tatsächlich wiesen die adulten Schafe eine rechtsventrikuläre Hypertrophie auf und bildeten so ein Cor pulmonale aus. Somit sind die hier beschriebenen Ergebnisse vergleichbar mit denen, bisher etablierten Methoden zur Ausbildung der PPHN. Lediglich der Muskularisierungsgrad der peripheren Pulmonalgefäße unterschied sich mit Blick auf andere Studien. In den adulten Schafslungen konnten verschiedene Signalwege identifiziert werden, anhand derer die persistierende PPHN erklärt werden könnte. Dabei lassen sich reaktive Sauerstoffspezies (ROS), als mögliches Schlüsselelement vermuten. Gene, die ROS produzieren oder abbauen können, Gene des HIF-Signalweges sowie Gene, die bei der Kontraktion/Relaxation der Pulmonalgefäße beteiligt sind, sind in ihren Expressionen verändert. Zusätzlich zeigte sich eine mögliche mitochondriale Beteiligung bei der Entstehung der PPHN. Wie genau diese in adulten Schafen persistierenden Mechanismen in den fetalen Schafen reguliert wurden, konnte jedoch nicht aufgezeigt werden. Weiterführende Untersuchungen an lasermikrodissezierten Gefäßen sowie Antikörperfärbungen zeigten eine mögliche parakrine Aktivität der Bronchien, die das vaskuläre Remodeling der Pulmonalgefäße verstärkt / initiiert haben könnten. Vitamin C könnte als Radikalfänger in die Dysbalance der vasoaktiven Substanzen eingegriffen haben und unter der Eliminierung von ROS das Gleichgewicht wiederherstellt haben. Die pränatale Vitamin-C-Gabe verhinderte die Ausbildung der PPHN sowohl in den fetalen als auch heranwachsenden adulten Schafen, das sich anhand der stereologischen, histologischen und molekularbiologischen Ergebnisse der vorliegenden Arbeit belegen lässt und scheint in dem hier vorliegenden Modell somit protektiv zu wirken.
- Published
- 2023
- Full Text
- View/download PDF
34. Cardiopulmonary resuscitation in pediatric patients under palliative home care – A multicenter retrospective study
- Author
-
Schneck, Emmanuel, Janßen, Gisela, Vaillant, Vera, Voelker, Thomas, Dechert, Oliver, Trocan, Laura, Schmitz, Lioba, Rohde, Marius, Sander, Michael, Hauch, Holger, and Justus Liebig University Giessen
- Subjects
ddc:610 ,advanced pediatric life support ,palliative home care ,CPR ,rare diseases ,end-of-life ,ethics ,chronic illness ,emergency medial services - Abstract
Introduction: Patients under palliative home care have special needs for their end-of-life support, which in general does not automatically include cardiopulmonary resuscitation. However, emergency medical services (EMS) respond to emergencies in children under palliative care that lead to cardiopulmonary resuscitation. To understand the underlying steps of decision-making, this retrospective, cross-sectional, multicenter study aimed to analyze pediatric patients under palliative home care who had been resuscitated. Methods: This study included patients from three spezialized pediatric palliative home care (SHPC) teams. The primary study parameters were the prevalence of cardiopulmonary resuscitation and the decision-making for carrying out pediatric advanced life support (PALS). Further analyses included the causes of cardiac arrest, the type of CPR (basic life support, advanced life support), the patient´s outcome, and involvement of the SHPC in the resuscitation. Descriptive statistical analysis was performed. Results: In total, 880 pediatric patients under palliative home care were included over 8.5 years, of which 17 patients were resuscitated once and two patients twice (overall, 19 events with CPR, 21.6 per 1,000 cases). In 10 of the 19 incidents (52.6%), cardiac arrest occurred suddenly without being predictable. The causes of cardiac arrest varied widely. PALS was performed in 78.9% of the cases by EMS teams. In 12 of 19 events (63.2%) resuscitation was performed on explicit wish of the parents. However, from a medical point of view, only four resuscitation attempts were reasonable. In total 7 of 17 (41.2%) patients survived cardiac arrest with a comparable quality of life. Discussion: Overall, resuscitation attempts were rare events in children under home palliative therapy, but if they occur, EMS are often the primary caregivers. Most resuscitation attempts occurred on explicit wish of the parents independently of the meaningfulness of the medical procedure. Despite the presence of a life-limiting disease, survival with a similar quality was achieved in one third of all resuscitated patients. This study indicates that EMS should be trained for advanced life support in children under home palliative therapy and SHPC should address the scenario of cardiac arrest also in early stages of palliative treatment. These results underline that advance care planning for these children is urgently needed.
- Published
- 2023
- Full Text
- View/download PDF
35. Estimated plasma volume status: association with congestion, cardiorenal syndrome and prognosis in precapillary pulmonary hypertension
- Author
-
Yogeswaran, Athiththan, Richter, Manuel J., Husain-Syed, Faeq, Rako, Zvonimir, Sommer, Natascha, Grimminger, Friedrich, Seeger, Werner, Ghofrani, Hossein Ardeschir, Gall, Henning, Tello, Khodr, and Justus Liebig University Giessen
- Subjects
glomerular filtration rate ,ddc:610 ,pulmonary arterial hypertension ,survival ,fluid balance ,chronic thromboembolic pulmonary hypertension - Abstract
Background: Volume overload is often associated with clinical deterioration in precapillary pulmonary hypertension (PH). However, thorough assessment of volume overload is complex and therefore not routinely performed. We examined whether estimated plasma volume status (ePVS) is associated with central venous congestion and prognosis in patients with idiopathic pulmonary arterial hypertension (IPAH) or chronic thromboembolic PH (CTEPH). Methods: We included all patients with incident IPAH or CTEPH enrolled in the Giessen PH Registry between January 2010 and January 2021. Plasma volume status was estimated using the Strauss formula. Results: In total, 381 patients were analyzed. Patients with high ePVS (≥4.7 vs.
- Published
- 2023
- Full Text
- View/download PDF
36. Frequency and characteristics of diabetes in lipodystrophies and insulin receptoropathies compared with type 1 and type 2: results from the multicenter DPV registry
- Author
-
Kamrath, Clemens, Eckert, Alexander, Rami-Merhar, Birgit, Kummer, Sebastian, Wabitsch, Martin, Laubner, Katharina, Kopp, Florian, Müther, Silvia, Mühldorfer, Steffen, Holl, Reinhard W, and Justus Liebig University Giessen
- Subjects
ddc:610 ,diabetes ,rare diseases/syndromes - Abstract
Objective: To investigate the frequency, treatment, and outcome of patients with diabetes due to severe insulin resistance syndromes (SIRS). Research Design and Methods: Based on data from the multicenter prospective Diabetes Registry DPV, we analyzed diagnosis, treatment, and outcome of 636,777 patients with diabetes from 1995 to 2022. Results: Diabetes due to SIRS was documented in 67 cases (62.7% females), 25 (37%) had lipodystrophies (LD) and 42 (63%) had congenital defects of insulin signaling. The relative frequency compared to type 1 diabetes (T1D) was about 1:2300. Median age at diabetes diagnosis in patients with SIRS was 14.8 years (interquartile range (IQR) 12.8–33.8). A total of 38 patients with SIRS (57%) received insulin and 34 (51%) other antidiabetics, mostly metformin. As high as 16% of patients with LD were treated with fibrates. Three out of eight patients with generalized LD (37.5%) were treated with metreleptin and one patient with Rabson–Mendenhall syndrome was treated with recombinant insulin-like growth factor 1. The median glycated hemoglobin level at follow-up was 7.1% (54 mmol/mol). Patients with LD had higher triglycerides than patients with T1D and T2D (P < 0.001 and P = 0.022, respectively), and also significantly higher liver enzymes and lower high-density lipoprotein cholesterol than patients with T1D (P < 0.001). Patients with insulin receptor disorders were significantly less likely to be treated with antihypertensive medication than patients with T2D (P = 0.042), despite having similar levels of hypertension. Conclusions: Diabetes due to SIRS is rarely diagnosed and should be suspected in lean children or young adults without classical T1D. Awareness of cardiovascular risk factors in these patients should be raised.
- Published
- 2023
- Full Text
- View/download PDF
37. Membrane-type matrix metalloproteinases: membrane-type 1 matrix metalloproteinase, membrane-type 2 matrix metalloproteinase and membrane-type 3 matrix metalloproteinase in endometriosis and adenomyosis
- Author
-
Maoga, Jane Bosibori and Justus Liebig University Giessen
- Subjects
ddc:610 ,Endometriosis ,Membrane-type matrix metalloproteinases ,eutopic and ectopic endometrium ,ddc:570 ,Adenomyosis - Abstract
Endometriosis is a benign gynecological disease characterized by the presence of endometrial tissue; endometrial glands and stroma outside the uterus. Even though endometriosis affects about 0.7-8.6% women of the reproductive age, the pathogenesis is not well understood and there is no reliable non-invasive biomarker for diagnosis. Matrix metalloproteinases are significantly expressed in the endometrium and also in endometriosis. The aim of this study was to investigate the role of membrane-type MMPs in the pathogenesis of endometriosis. To achieve this, we analysed tissue samples from patients with and without endometriosis, adenomyotic lesions and the three endometriotic entities; ovarian, peritoneal and deep infiltrating endometriosis and evaluated their HSCORE and percentage of stained glands. Also, we studied the levels of MT1-MMP in serum and endocervical mucus samples of patients with and without endometriosis. In addition, we also investigated MT1-, MT2- and MT3-MMP protein expression in endometrial and endometriotic cells and the role of MT1-MMP and MT3-MMP in betaglycan shedding in endometriotic epithelial cells. Our results showed that all studied MT-MMPs are expressed in the human endometrium with high similarities between women with and without endometriosis except for MT1- MMP which we only evaluated in few samples. Variations in protein expression were found with a reduced MT1-MMP expression in ovarian endometriosis, MT2-MMP in ovarian, peritoneal and deep infiltrating endometriosis as well as MT3-MMP in peritoneal and deep infiltrating endometriosis. Similarly, in adenomyosis, MT1-MMP was increased while MT2-MMP and MT3-MMP abundance was highly identical to eutopic endometrium. Consequently, we suggest that variations most likely occur after implantation of the endometriotic tissue in the ectopic sites and endometrial glands could be the sole source of adenomyotic glands. This could also suggest that endometriosis and adenomyosis do not share a common pathogenesis but are distinguishable by, invasion versus invagination, respectively. In addition, we demonstrated that MT1-MMP levels in endocervical mucus of patients with and without endometriosis were highly similar. Furthermore, we revealed that MT1- MMP concentration in endocervical mucus samples of patients with endometriosis was decreased by hormonal contraceptives, but further investigations are needed to ascertain the specific contraceptions involved. Our results further revealed that MT1-MMP, MT2-MMP and MT3-MMP proteins are expressed in endometrial and endometriotic cells and downregulation of MT1-MMP and MT3-MMP had no effect on betaglycan shedding. Taken together, these findings provide new evidence on the function of MT1-, MT2- and MT3-MMP in the pathophysiology of endometriosis and adenomyosis. However, more experiments are needed to understand the role of these proteins in adenomyosis and endometriosis using primary endometrial and endometriotic cells as well as animal models.
- Published
- 2023
- Full Text
- View/download PDF
38. Ligamentum arteriosum and its telocytes: An ultrastructure description
- Author
-
Quaye Mensah, Benedicta and Justus Liebig University Giessen
- Subjects
ddc:610 - Published
- 2023
- Full Text
- View/download PDF
39. A Novel Insertion in the Hepatitis B Virus Surface Protein Leading to Hyperglycosylation Causes Diagnostic and Immune Escape
- Author
-
Lehmann, Felix, Slanina, Heiko, Roderfeld, Martin, Roeb, Elke, Trebicka, Jonel, Ziebuhr, John, Gerlich, Wolfram H., Schüttler, Christian G., Schlevogt, Bernhard, Glebe, Dieter, and Justus Liebig University Giessen
- Subjects
N-linked glycosylation ,ddc:610 ,immune escape ,hepatitis B virus ,diagnostic escape - Abstract
Chronic hepatitis B virus (HBV) infection is a global health threat. Mutations in the surface antigen of HBV (HBsAg) may alter its antigenicity, infectivity, and transmissibility. A patient positive for HBV DNA and detectable but low-level HBsAg in parallel with anti-HBs suggested the presence of immune and/or diagnostic escape variants. To support this hypothesis, serumderived HBs gene sequences were amplified and cloned for sequencing, which revealed infection with exclusively non-wildtype HBV subgenotype (sgt) D3. Three distinct mutations in the antigenic loop of HBsAg that caused additional N-glycosylation were found in the variant sequences, including a previously undescribed six-nucleotide insertion. Cellular and secreted HBsAg was analyzed for N-glycosylation in Western blot after expression in human hepatoma cells. Secreted HBsAg was also subjected to four widely used, state-of-the-art diagnostic assays, which all failed to detect the hyperglycosylated insertion variant. Additionally, the recognition of mutant HBsAg by vaccine- and natural infection-induced anti-HBs antibodies was severely impaired. Taken together, these data suggest that the novel six-nucleotide insertion as well as two other previously described mutations causing hyperglycosylation in combination with immune escape mutations have a critical impact on in vitro diagnostics and likely increase the risk of breakthrough infection by evasion of vaccineinduced immunity.
- Published
- 2023
- Full Text
- View/download PDF
40. The Impact of Recirculation on Extracorporeal Gas Exchange and Patient Oxygenation during Veno-Venous Extracorporeal Membrane Oxygenation—Results of an Observational Clinical Trial
- Author
-
Gehron, Johannes, Bandorski, Dirk, Mayer, Konstantin, Böning, Andreas, and Justus Liebig University Giessen
- Subjects
critical care ,ddc:610 ,ultrasound dilution ,recirculation ,circulatory and respiratory physiological phenomena ,acute respiratory distress syndrome ,veno-venous extracorporeal membrane oxygenation - Abstract
Background: Recirculation during veno-venous extracorporeal membrane oxygenation reduces extracorporeal oxygen exchange and patient oxygenation. To minimize recirculation and maximize oxygen delivery (DO2) the interaction of cannulation, ECMO flow and cardiac output requires careful consideration. We investigated this interaction in an observational trial. Methods: In 19 patients with acute respiratory distress syndrome and ECMO, we measured recirculation with the ultrasound dilution technique and calculated extracorporeal oxygen transfer (VO2), extracorporeal oxygen delivery (DO2) and patient oxygenation. To assess the impact of cardiac output (CO), we included CO measurement through pulse contour analysis. Results: In all patients, there was a median recirculation rate of approximately 14–16%, with a maximum rate of 58%. Recirculation rates >35% occurred in 13–14% of all cases. In contrast to decreasing extracorporeal gas exchange with increasing ECMO flow and recirculation, patient oxygenation increased with greater ECMO flows. High CO diminished recirculation by between 5–20%. Conclusions: Extracorporeal gas exchange masks the importance of DO2 and its effects on patients. We assume that increasing DO2 is more important than reduced VO2. A negative correlation of recirculation to CO adds to the complexity of this phenomenon. Patient oxygenation may be optimized with the direct measurement of recirculation.
- Published
- 2023
- Full Text
- View/download PDF
41. Clathrin-Mediated Albumin Clearance in Alveolar Epithelial Cells of Murine Precision-Cut Lung Slices
- Author
-
Kryvenko, Vitalii, Alberro-Brage, Andrés, Fysikopoulos, Athanasios, Wessendorf, Miriam, Tello, Khodr, Morty, Rory E., Herold, Susanne, Seeger, Werner, Samakovlis, Christos, Vadász, István, and Justus Liebig University Giessen
- Subjects
ddc:610 ,alveolar epithelium ,endocytosis ,protein transport ,precision-cut lung slices ,acute respiratory distress syndrome ,albumin - Abstract
A hallmark of acute respiratory distress syndrome (ARDS) is an accumulation of protein-rich alveolar edema that impairs gas exchange and leads to worse outcomes. Thus, understanding the mechanisms of alveolar albumin clearance is of high clinical relevance. Here, we investigated the mechanisms of the cellular albumin uptake in a three-dimensional culture of precision-cut lung slices (PCLS). We found that up to 60% of PCLS cells incorporated labeled albumin in a time- and concentration-dependent manner, whereas virtually no uptake of labeled dextran was observed. Of note, at a low temperature (4 °C), saturating albumin receptors with unlabeled albumin and an inhibition of clathrin-mediated endocytosis markedly decreased the endocytic uptake of the labeled protein, implicating a receptor-driven internalization process. Importantly, uptake rates of albumin were comparable in alveolar epithelial type I (ATI) and type II (ATII) cells, as assessed in PCLS from a SftpcCreERT2/+: tdTomatoflox/flox mouse strain (defined as EpCAM+CD31−CD45−tdTomatoSPC−T1α+ for ATI and EpCAM+CD31−CD45−tdTomatoSPC+T1α− for ATII cells). Once internalized, albumin was found in the early and recycling endosomes of the alveolar epithelium as well as in endothelial, mesenchymal, and hematopoietic cell populations, which might indicate transcytosis of the protein. In summary, we characterize albumin uptake in alveolar epithelial cells in the complex setting of PCLS. These findings may open new possibilities for pulmonary drug delivery that may improve the outcomes for patients with respiratory failure.
- Published
- 2023
- Full Text
- View/download PDF
42. Clinical characteristic, psychometric properties, novel diagnostic methods and outcomes in interstitial lung diseases
- Author
-
Krauss, Ekaterina and Justus Liebig University Giessen
- Subjects
Idiopathische pulmonale Fibrose ,ddc:610 ,eurIPFreg ,eurILDreg ,Interstitielle Lungenerkrankungen - Abstract
In this research, we report detailed clinical characteristics of a large European IPF cohort with outcome data extending up to 10 years. Our patients are diverse in age, impairment of lung function, therapeutic regimes and co-morbidities. In this regard, the diversity of the eurIPFreg- cohort may reflect not only the variety in natural course of the disease, but also changes in clinical management of the patients, especially when comparing our results to historic IPF data and data from controlled clinical phase III trials. Thus, the decline in the usage of prednisolone and other immunosuppressive medication reflects the implementation of recent IPF guidelines, and the knowledge arising from the PANTHER-IPF trial, according to which these therapeutic strategies are rather harmful than helpful in IPF. Our registry data also reflect the steady increase in the use of cryobiopsy for diagnosis and of usage of antifibrotic drugs. However, our data indicate that IPF still has a high mortality rate and that survival times are quite heterogenous, reflecting both, the heterogeneous natural course of IPF in a clinical setting, ranging from stable disease to a rapid progressive fibrosis, and the change in the pharmacological approach to IPF subjects. The presented work also reflect changes in the diagnostic and therapeutic approach in IPF in the last ten years, supporting the important role of large real-world data registries to document and scrutinize changes in IPF management. Furthermore, a real-life ILD-data registry significantly complements data from randomised controlled trials, typically comprising a wide range of severity, progression and co-morbidities. Prognostic indicators for IPF patients under antifibrotic treatment have yet to be established in the future, using epidemiological data and taking into account a larger numbers of patients with definite outcome data and longer follow up periods.
- Published
- 2022
- Full Text
- View/download PDF
43. 'Sperm-Retrieval': TEstikuläre SpermatozoenEntnahme (TESE) bei Non-Obstruktiver Azoospermie (NOA) - Optimierung der Patientenauswahl, Implementierung der chirurgischen Technik und vergleichende Beurteilung zwischen Makro- und Mikro-TESE
- Author
-
Keudel, Andreas and Justus Liebig University Giessen
- Subjects
ddc:610 ,TESE - Abstract
Am Standort Gießen bestand ein chirurgischer Konsens darüber, dass eine Trifokale Makro-TESE bei der Diagnose NOA durchgeführt werden sollte. Nach der internationalen Einführung der Mikro-TESE, die zu einer Verbesserung des „Sperm Retrievals“ bei NOA führen sollte, folgte ein sprunghafter Anstieg an Zuweisungspatienten am Standort Gießen, an dem diese mikrochirurgische Technik etabliert und jede zusätzliche Mikro-TESE eine weitere Chance für ein erfolgreicheres „Sperm Retrieval“ bieten sollte. Ziel der Arbeit war eine Optimierung der Patientenauswahl, Implementierung der chirurgischen Technik und vergleichende Beurteilung zwischen Makro- und Mikro-TESE. Die Gießener Arbeitsgruppe hat dazu beim Überweisungskollektiv von 182 Patienten zur TESE eine entsprechende subtile Diagnostik zwecks Optimierung der Patientenauswahl eingeführt. Bei 32 Patienten fand sich keine Azoospermie bei wiederholter Ejakulatanalyse, 59 Patienten wurden mit einem obstruktiven Faktor assoziiert. Bei 8 beziehungsweise 2 Patienten lag eine Kongenitale Bilaterale Aplasie des Vas Deferens (CBAVD) und ein zentraler Verschluss vor. Bei 26 Patienten wurde eine gemischte Azoospermie diagnostiziert, das heißt, neben einem testikulären Schaden lag auch der Verdacht auf eine obstruktive Azoospermie vor. Zur vergleichenden Beurteilung des „Sperm Retrieval“ wurden 65 Patienten einer „Low Chance NOA“ Gruppe nach Tüttelmann zugeordnet, das heißt mit gesicherter testikulärer Azoospermie, mit einem erhöhtem FSH-Serumspiegel über 12,4 IU/l und einem geringem Hodenvolumen unter 8ml für beide Hoden. Die Gießener Arbeitsgruppe nutzte als chirurgisches Standardverfahren eine Trifokale Makro-TESE aus oberem, mittlerem und unterem Hodenpol am lateralen freien Gefäßrand. Ergänzt wurde dies um eine mikrochirurgische Erweiterung der mittlerern Inzision, die sogenannte Mikro-TESE. Ziel war unterschiedliche „Sperm Retrieval“ Raten für die Makro- versus Mikro-TESE intraindividuell vergleichen zu können. Zusätzlich sollte untersucht werden, ob der Einsatz der Mikro-TESE im Trifokalen Makro-TESE Konzept die Ausbeute des „Sperm Retrieval“ verbessern könnte. Wie erwartet wurden bei der Trifokalen Makro-TESE signifikant mehr auswertbare Hodentubuli im Vergleich zur Mikro-TESE gefunden. Jedoch war die Anzahl auswertbarer Tubuli mit mindestens einer elongierten Spermatide bei der Mikro-TESE signifikant höher als bei der Trifokalen Makro-TESE. Auch der Bergmann/Kliesch Score war bei der Mikro-TESE signifikant höher als bei der Trifokalen Makro-TESE. Bei der Analyse des „Sperm Retrievals“ erwies sich nur die Kombination aus Trifokaler-Makro-TESE plus Mikro-TESE als statistisch nachweisbar besser im Vergleich zur Unifokalen-Makro-TESE. Die vorgelegte Untersuchung zum „Sperm Retrieval“ erzielte in der Hochrisikogruppe „Low Chance NOA“ bei der Trifokalen Makro-TESE und zusätzlicher Mikro-TESE mit 66,2% erfolgreichem „Sperm Retrieval“ sehr gute Werte. Damit war die Trifokale Makro-TESE in Kombination mit der Mikro-TESE besonders erfolgreich.
- Published
- 2022
- Full Text
- View/download PDF
44. The effects of smoking on inflammatory and angiogenic pathways in the retina of mice
- Author
-
Wang, Feng and Justus Liebig University Giessen
- Subjects
ddc:610 ,Inflammatory reaction ,E-cigarette vapor ,Angiogenesis ,C-cigarette smoke ,AMD - Abstract
Cigarette smoke has been identified as a major risk factor for the development of age-related macular degeneration (AMD). As an alternative of conventional cigarette (C-cigarette), electronic cigarette (E-cigarette) has been rapidly promoted and used globally. The increasing usage of E-cigarette raises concerns with regard to long-term consequences related to retinal tissue. In the present study, a controlled study in mice models was conducted to probe the comprehensive effects of E-cigarette on retina, RPE and choroid tissues by (1) comparing the effect of C-cigarette smoke and E-cigarette smoke on retina; (2) determining the effects of E-cigarette vapor on the RPE and analyzing the changes with regard to inflammatory and angiogenic mediators in retina/RPE/choroid. The data showed that C-cigarette smoke exposure promoted an inflammatory reaction in the retina in vivo. Mice exposed to E-cigarette (nicotine-free) vapor developed inflammatory and angiogenic reactions more pronounced in RPE and choroid, while nicotine-containing E-cigarette vapor caused even a more serious reaction. Both, inflammatory and pro-angiogenic reactions increased with the extension of exposure time. These results demonstrate that exposure to C-cigarette smoke is harmful to the retina. Likewise, the exposure to E-cigarette vapor (with or without nicotine) increases the occurrence and progression of inflammatory and angiogenic stimuli in the retina, which might be similar effects causing the onset of wet AMD in humans.
- Published
- 2022
- Full Text
- View/download PDF
45. Ätiologie und 30-Jahres-Überleben von herztransplantierten Kindern mit einer Kardiomyopathie. Eine retrospektive, monozentrische, nicht randomisierte Studie am Kinderherzzentrum Gießen
- Author
-
Zschirnt, Martin and Justus Liebig University Giessen
- Subjects
Kardiomyopathien ,ddc:610 ,Herztransplantation ,Kinderkardiologie - Abstract
Einleitung: Studien zur Beurteilung des Langzeitergebnisses nach HTx auf dem Boden einer Kardiomyopathie (CM) im pädiatrischen Altersbereich sind selten. Ziel dieser Studie war es, die Überlebensrate von Kindern mit CM nach HTx zu bestimmen und zu analysieren, wie die Ätiologie das neurologische und kognitive outcome sowie die Mortalität beeinflusst. Methoden: Die Analyse der medizinischen Datenbank der transplantierten Kinder des Hessischen Kinderherzzentrums, erfolgte retrospektiv zwischen Juni 1988 und Oktober 2019. Dabei wurden seit 1988 236 Herztransplantationen durchgeführt inklusive neun Retransplantationen. Ergebnisse: 98 von 227 Patienten (43,2 %) wurden wegen einer CM transplantiert. Die Überlebensrate betrug 93 % nach einem, 84 % nach 10 und 75 % nach 30 Jahren. Die Überlebenswahrscheinlichkeit war bei Kindern, die von 2000 bis 2009 und von 2010 bis 2019 transplantiert wurden, signifikant höher als bei denjenigen, die zwischen 1988 und 1999 ein neues Herz erhielten (p < 0,01). Insgesamt konnte die Ätiologie der CM bei 37 Probanden (37,7 %) eindeutig identifiziert werden. Diese Rate stieg durch eine umfassende diagnostische Aufarbeitung seit 2016 von initial 0% auf bis zu 66,6 % (12/19). Die Überlebensrate war niedriger (p < 0,05) und neurokognitive Defizite traten bei Kindern mit systemischen Erkrankungen häufiger auf (p = 0,001) als bei Patienten mit kardialspezifischen Erkrankungen. Schlussfolgerung: Diese Daten weisen darauf hin, dass die Langzeitüberlebensrate von Kindern mit CM nach HTx in ‚high volume‘-Zentren hoch ist. Die Ergebnisse deuten auch darauf hin, dass eine umfassende diagnostische Aufarbeitung es erlaubt, den Basisdefekt bei der Mehrzahl der Patienten mit CM nach HTx zu diagnostizieren. Die Ätiologie der CM scheint das neurologische und kognitive outcome sowie die Mortalität bei Kindern, die eine HTx benötigen, zu beeinflussen.
- Published
- 2022
- Full Text
- View/download PDF
46. Ableitung und Validierung eines synthetischen Hämatokritwertes aus parametrischen T1 Daten der kardialen Magnetresonanztomografie : Daten aus einem prospektiven MR-Register
- Author
-
Nunn, Samuel and Justus Liebig University Giessen
- Subjects
ddc:610 ,Gewebecharakterisierung ,extrazelluläres Volumen ,Kardiologie ,Magnetresonanztomografie ,Kerckhoff Klinik - Abstract
Hintergrund: Die Quantifizierung des extrazellulären Volumens (ECV) in der kardialen Magnetresonanztomografie (MRT) erlaubt eine Messbarkeit des Extrazellularraumes, welcher sich bei diffusem Odem und Fibrose ver ändert. Dies tritt vor allem in frühen Stadien von Herzmuskelerkrankungen ein. Normalerweise wird hierfür eine tagesaktuelle venöse Hämatokritbestimmung zur Berechnung des extrazelluläre Volumen (ECV) benötigt. Eine beschriebene Alternative stellt das Verhältnis der longitudinalen Relaxationszeiten (T1) des Blutes vor und nach Kontrastmittelapplikation dar. Mit Hilfe des berechneten synthetischen Hämatokrits kann im Folgenden das synthetische ECV berechnet werden, was durch den Verzicht einer tagesaktuellen venösen Blutprobe den Patientenkomfort steigert und auf einen Arbeitsschritt in der klinischen Routine verzichtet werden kann. Zielsetzung: Ziel dieser Studie ist zu Reevaluieren, ob ein Zusammenhang zwischen dem venös gemessenen Hämatokrit und der T1 Relaxationszeit des Blutes besteht, sodass im Weiteren ein synthetisches ECV berechnet werden kann. Dies wird an einer großen Anzahl an eingeschlossenen Patienten mit zahlreicher myokardialen Erkrankungen untersucht. Methoden: 1.132 freiwillig eingeschlossene Patienten, die aus klinischer Indikation mittels kardialer MRT untersucht wurden, werden in eine Derviations- (n = 564) und Validationskohorte (n = 568) randomisiert. Das ECV wird mittels T1 Relaxationszeit im septalen Myokard und im linksventrikul ären Blutpool im 3 Tesla MRT mittels Modified Look-Locker inversion recovery (MOLLI) Sequenzen bestimmt. Zusätzlich wurde ein tagesaktueller venöser Hämatokrit bestimmt. Der synthetische Hämatokritwert wurde mittels linearer Regressionsanalyse zwischen gemessenem Hämatokrit und R1 = 1/T1 des Blutes bestimmt. Mittels Korrelationen wurde dieser mit dem gemessenen Hämatokrit verglichen. Im weiteren Verlauf wurde das gemessene und synthetische ECV bestimmt und mittels Bland-Altman Analysen verglichen. Ergebnisse: In der Derviationskohorte zeigte der venöse Hämatokrit und die R1 des Blutes eine linearen Zusammenhang (R2 = 0,18; Korrelationskoeffizient: 0,43, 95 % Konfidenzintervall (CI) 0,36 - 0,49). Hieraus wurde der synthetische Hämatokrit und das synthetische ECV berechnet. Das synthetische ECV korreliert stark mit dem gemessenen ECV (Korrelationskoeffizient: 0,91 CI 0,90 - 0,92). Die mittlere Abweichung beträgt -0,05 (CI -0,19 - 0,09), die Zustimmungsgrenzen liegen bei -4,69 und 4,59. Fazit: Trotz der schlechten Korrelation zwischen synthetischem und gemessenem venösen Hämatokrit zeigt sich eine exzellente Korrelation zwischen synthetischem und gemessenem ECV. Aus diesem Grund kann man an großen Patienten- und Probandenkohorten einen nichtinvasiven Marker für das extrazelluläre Volumen des Myokards in der alltäglichen klinischen Routine bestätigen.
- Published
- 2022
- Full Text
- View/download PDF
47. Characterization of the autophagy machinery in Schistosoma mansoni, a parasite of public health relevance
- Author
-
Mughal, Mudassar Niaz and Justus Liebig University Giessen
- Subjects
ddc:610 ,ddc:630 - Abstract
Schistosomiasis is caused by dioecious schistosomes of the genus Schistosoma and is a neglected tropical disease of global importance for human and animal health. Praziquantel represents the only widely used drug to combat schistosomiasis. Due to concerns of developing drug resistance, the search for novel drug and vaccine candidates represents a feasible approach to fight schistosomiasis. As a first part, my work focused on autophagy-related genes which, due to highevolutionary conservation, are potential regulators of autophagy. I identified seven autophagy genes (Beclin, Ambra1, Vps34, LC3B, DRAM, DAP1) in S. mansoni by in silico analyses and investigated the influence of in vitro culture conditions on the mRNA transcriptional level of these autophagy genes in male and female adult parasites based on quantitative real-time PCR. Among the autophagy-associated genes, some exhibited sex-dependent expression patterns. For example, the death-associated protein DAP1 in S. mansoni was found to be highly expressed in females compared to males. The opposite applied to the damage-regulated autophagy modulator DRAM. In addition, the effect of in vitro culture conditions significantly changed the mRNA expression level of DAP1 only in female S. mansoni. The conversion of LC3B-I into LC3B-II, a marker for autophagic flux, was increased by rapamycin and blocked by bafilomycin A1 (BA1) treatment of parasites as observed by western blot analyses. Furthermore, all tested autophagy inhibitors, BA1, wortmannin, and spautin-1 affected worm viability and egg production. All inhibitors drastically influenced the intestinal and gonadal morphology as shown by confocal laser scanning microscopy (CLSM). As a second part, I observed an anticancer drug, imatinib drastically affected intestinal morphology and caused the death of adult worms at 50 μM or higher concentrations within 3-4 days in vitro (already published). Adult parasites were co-treated with imatinib and BA1. I identified a significant increase of LC3B protein following imatinib treatment. Of note, the drastic effects induced by imatinib on pairing stability, egg production, gut dilatation were mitigated by BA1. Furthermore, the mRNA levels of cathepsins, genes predominantly expressed in the schistosome gut, were reversed upon BA1 treatment in imatinib-treated male parasites. These results provided a possible explanation for the deleterious gut phenotype caused by imatinib, which might in part be explained by autophagy induction. In general, my results indicated that autophagy regulation in S. mansoni represents not only a defense mechanism regulating cellular homeostasis, but when disrupted by chemical inhibition, can affect parasite viability and reproduction.
- Published
- 2022
- Full Text
- View/download PDF
48. Essenzielle Rolle des Komplexes II der Atmungskette bei der hypoxie-induzierten ROS-Produktion in den Gefäßwandzellen der Lungenstrombahn
- Author
-
Ishaq, Barat and Justus Liebig University Giessen
- Subjects
ddc:610 - Abstract
Bei der hypoxischen pulmonalen Vasokonstriktion (HPV) verengen sich die intrapulmonalen Arterien als Reaktion auf eine alveoläre Hypoxie und leiten das Blut in besser ventilierte Lungenbereiche um, es findet also eine Anpassung der Perfusion an die Ventilation statt. Weder die molekulare Natur des Sauerstoffsensors noch der Signalweg, der zu einer HPV führt, waren zu Beginn dieser Arbeit vollständig entschlüsselt, wobei aber Hinweise auf eine Beteiligung von Stickstoffmonoxid (NO) oder vermutlich in den Mitochondrien gebildeten reaktiven Sauerstoffspezies (ROS) vorlagen. Ziel der Arbeit war daher die quantitative Erfassung zellulärer NO- und ROS-Produktion in pulmonalarteriellen Gefäßen unter Norm- und Hypoxie. Dazu wurden 200 µm dicke lebende Schnitte von Mauslungen in Gegenwart der fluoreszierenden Indikatoren DCF-DA (Nachweis von ROS) bzw. DAF-2DA (Nachweis von NO) unter normxischen bzw. hypoxischen Bedingungen kultiviert und anschließend die positiven Zellen und ihre Signalstärke in den Wänden der Gefäße fluoreszenzmikroskopisch quantifiziert. Die Succinatdehydrogenase-Aktivität (SDH-Aktivität) des mitochondrialen Komplexes II wurde mittels eines histochemischen Verfahrens quantitativ analysiert. Während die Anzahl NO-produzierender Zellen in der Gefäßwand durch Hypoxie nicht verändert wurde, war die Anzahl der ROS-generierenden Zellen signifikant erhöht. Die Zugabe spezifischer Inhibitoren (DPI zur Hemmung von Flavoproteinen, Rotenon zur Hemmung von Komplex I, 3-NPA und TTFA von Komplex II, Antimycin A von Komplex III und NaN3 von Komplex IV) ergab, dass die mitochondriale Atmungskette die Quelle von ROS war. Die Beteiligung der einzelnen Komplexe unterschied sich in der normoxischen und hypoxischen ROS-Bildung. Während für die normoxische ROS-Erzeugung die Komplexe I und III erforderlich waren, erforderte die hypoxische ROS-Bildung zusätzlich den Komplex II. Die histochemisch nachweisbare SDH-Aktivität von Komplex II in Zellen der intrapulmonalen Arterien nahm unter Hypoxie ab. Die Hemmung der umgekehrten enzymatischen Reaktion der SDH, d.h. die Fumarat-Reduktase, durch Zugabe von Succinat verhinderte spezifisch die hypoxische, nicht aber die normoxische ROS-Bildung. Somit spielt Komplex II eine wesentliche Rolle bei der hypoxischen ROS-Produktion. Vermutlich wechselt seine katalytische Aktivität bei verringertem Sauerstoffpartialdruck von SDH zu Fumarat-Reduktase, wodurch die Richtung des Elektronenflusses moduliert wird.
- Published
- 2022
- Full Text
- View/download PDF
49. Vergleich zwischen 64-Zeilen und 192-Zeilen Dual-Source Computertomografie hinsichtlich Erkennung obstruktiver Erkrankungen der Herzkranzgefäße im Rahmen der Evaluation von Erkrankten vor transkatheter Aortenklappenimplantation
- Author
-
Steinbach, Robert and Justus Liebig University Giessen
- Subjects
TAVI ,ddc:610 - Abstract
Ziel: Die Verwendung verschiedener DSCT(Dual-Source-Computertomografie)-Generationen kann die Bildqualität, die Strahlungsdosis und die benötigte Kontrastmittelmenge beeinflussen. Ziel dieser Studie ist es, 64- und 192-Zeilen-DSCT hinsichtlich dieser Aspekte und der Genauigkeit im Nachweis einer koronaren Herzkrankheit (KHK) in der Computertomografie-Angiografie (CTA) im Rahmen der Transkatheter-Aortenklappenimplantation (TAVI) zu vergleichen. Material und Methoden: Diese Studie umfasste 192 Erkrankte, die sich vor TAVI einer CTA und einer invasiven Koronarangiografie unterzogen hatten. Jeweils 96 Betroffene wurden mittels DSCT der ersten (60 Frauen, 81,50 (79,00 - 85,90) Jahre) oder dritten Generation (62 Frauen, 82,40 (79,80 - 85,10) Jahre) untersucht. Die Bildqualität (Signal-Rausch-Verhältnis (SNR), subjektive Bildqualität), die Strahlungsdosis, die Kontrastmittelmenge und die Fähigkeit zur Erkennung einer KHK wurden gemessen und die Ergebnisse der DSCT-Generationen verglichen. Eine Stenose von ≥ 70 % in der CTA wurde als signifikant definiert. Als Referenzstandard diente die invasive Koronarangiographie (KHK definiert als Stenose ≥ 50 % oder fractional flow reserve ≤ 0,80). Ergebnisse: Die DSCT der dritten Generation zeigte eine signifikant bessere subjektive (3 (IQR: 2 - 3) gegenüber 4 (IQR: 3 - 4,25) Punkte auf einer 5-Punkte-Likert-Skala) und objektive Bildqualität (SNR der linken Koronararterie 12,79 (IQR: 9,92 - 16,37) gegenüber 15,17 (IQR: 12,47 - 18,96)). Darüber hinaus gab es eine signifikant geringere Verwendung von Kontrastmittel (110 (IQR: 110 - 120) ml gegenüber 70 (IQR: 70 - 70) ml) und Strahlendosis (1001,00 (706,50 - 1312,00) mGy*cm gegenüber 726,50 (474,00 - 1369,30) mGy*cm) in der DSCT der dritten Generation. Genauigkeit, Sensitivität, Spezifität, positiver und negativer prädiktiver Wert zum Nachweis einer KHK waren unter Verwendung der 192-Zeilen-DSCT höher (69,80 %, 84,10 %, 57,70 %, 62,70 %, 81,10 % gegenüber 87,50 %, 87,50 %, 87,50 %, 83,30 %, 90,70 %). Zusammenfassung: Die Koronararterienbeurteilung mit CTA vor TAVI ist möglich. Im Vergleich zur DSCT der ersten Generation ist hier die moderne DSCT-Technologie überlegen, die weniger Kontrastmittel und Strahlendosis verbraucht und gleichzeitig eine bessere Bildqualität und diagnostische Genauigkeit bietet.
- Published
- 2022
- Full Text
- View/download PDF
50. Interaktion von Flotillin-2 mit desmosomalen Proteinen: Etablierung der BioID-Methode
- Author
-
Orczyk, Ralph Rene and Justus Liebig University Giessen
- Subjects
ddc:610 ,PV-IgG - Abstract
Pemphigus vulgaris ist eine schwere Autoimmunerkrankung, die durch eine Blasenbildung in der Haut und in den Schleimhäuten charakterisiert ist. Die Blasenbildung ist auf eine Akantholyse, d.h. eine Dissoziation des Epithelverbands, zurückzuführen. Diese wird durch Autoantikörper vom Typ IgG, auch PV-IgG genannt, ausgelöst, die vor allem gegen Desmoglein 3 gerichtet sind. Bei Desmogleinen handelt es sich um transmembranäre Glykoproteine, die speziell bei Desmosomen vorkommen. Man unterscheidet hier die Isoformen 1 bis 4. Letztendlich führt die Bindung der PV- IgG an das Desmoglein 3 zu einer Zerstörung von Desmosomen. Desmoglein 3 interagiert unter physiologischen Bedingungen im Rahmen der Funktion von Desmosomen zusammen mit Plakoglobin mit den Flotillinen. Die Flotillin-Familie besteht aus zwei Proteinen: Flotillin 1 und 2, wobei letzteres in dieser Arbeit untersucht wurde. Flotilline sind hochkonservierte und ubiquitär exprimierte Proteine. Durch Oligomerisierung und zusätzliche Palmitoyl- bzw. Myristoylreste sind sie in der Lage, an die Plasmamembran zu binden. Sie spielen beispielsweise eine Rolle im Signalweg des EGF-Rezeptors und der Clathrin- vermittelten Endozytose. Die vorliegende Arbeit hatte das Ziel, eine Methode zu etablieren, um das Interaktom von Flot2 darzustellen, sowie ein geeignetes Zellmodell für weitere Untersuchungen zu identifizieren. Mit Hilfe von Immunassays wurde zunächst die Klonierung und Expression von Flot2-Fusionsproteinen nachgewiesen; hierzu gehören Y163F-BirA* und Reg1-BirA*. Bei ersterem wurde ein Tyrosin an der 163. Stelle in der Aminosäuresequenz des Flot2 durch ein Phenylalanin ausgetauscht, letzteres stellt den Wildtyp von Flot2 dar. Y163 stellt im Flot2 eine wichtige Phosphorylierungstelle dar und ist damit für die Regulation seiner Funktion wichtig. Beide wurden mit einer bakteriellen Biotinligase fusioniert, wodurch Interaktionspartner von Flot2 anhand ihrer Biotinylierung identifiziert werden können. Unter Zuhilfenahme der Methodik der BioID konnte die Interaktion bei der Flot2-Mutanten mit Flotillin 1 in gleichem Ausmaß nachgewiesen werden wie zuvor mit der Methodik der Co-Immunpräzipiation. Damit eignet sich die BioID zur Untersuchung des gesamten Interaktoms. Außerdem wurde gezeigt, dass die Expression der Flot2 sowie dessen Interaktion mit endogenem Flotillin 1 in hTert Zellen unabhängig vom Calciumgehalt ist. Lediglich die Lokalisation von Flot2 ändert sich, sodass es bei intrazellulären Calciumspiegeln von 2 mmol/l vor allem an der Plasmamembran lokalisiert ist, während es bei Spiegeln von 0,05 mmol/l perinukleär lokalisiert ist. Darüber hinaus konnten die Zelllinien hTert, HaCaT sowie MCF7, als Flot2-Knockout Varianten, als die vielversprechendsten Zellmodelle für weitere Untersuchungen identifiziert werden.
- Published
- 2022
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.