Assessment of Bones Deficient in Fibrillin-1 Microfibrils Reveals Pronounced Sex Differences.

Defects in the extracellular matrix protein fibrillin-1 that perturb transforming growth factor beta (TGFβ) bioavailability lead to Marfan syndrome (MFS). MFS is an autosomal-dominant disorder, which is associated with connective tissue and skeletal defects, among others. To date, it is unclear how biological sex impacts the structural and functional properties of bone in MFS. The aim of this study was to investigate the effects of sex on bone microarchitecture and mechanical properties in mice with deficient fibrillin-1, a model of human MFS. Bones of 11-week-old male and female Fbn1mgR/mgR mice were investigated. Three-dimensional micro-computed tomography of femora and vertebrae revealed a lower ratio of trabecular bone volume to tissue volume, reduced trabecular number and thickness, and greater trabecular separation in females vs. males. Three-point bending of femora revealed significantly lower post-yield displacement and work-to-fracture in females vs. males. Mechanistically, we found higher Smad2 and ERK1/2 phosphorylation in females vs. males, demonstrating a greater activation of TGFβ signaling in females. In summary, the present findings show pronounced sex differences in the matrix and function of bones deficient in fibrillin-1 microfibrils. Consequently, sex-specific analysis of bone characteristics in patients with MFS may prove useful in improving the clinical management and life quality of these patients, through the development of sex-specific therapeutic approaches

Stress hormones or general well-being are not altered in immune-deficient mice lacking either T- and B- lymphocytes or Interferon gamma signaling if kept under specific pathogen free housing conditions

It is controversially discussed whether immune-deficient mice experience severity in the absence of infection. Because a comprehensive analysis of the well-being of immune-deficient mice under specific pathogen free conditions is missing, we used a multi-parametric test analyzing, corticosterone, weight, nest building and facial expression over a period of 9 month to determine the well-being of two immune-deficient mouse lines (recombination activating gene 2- and interferon gamma receptor-deficient mice). We do not find evidence for severity when comparing immune-deficient mice to their heterozygous immune-competent littermates. Our data challenge the assumption that immune-deficiency per se regardless of housing conditions causes severity. Based on our study we propose to use objective non-invasive parameters determined by laboratory animal science for decisions concerning severity of immune-deficient mice

Cardiovascular magnetic resonance feature tracking in small animals – a preliminary study on reproducibility and sample size calculation

Background Cardiovascular magnetic resonance feature tracking (CMR-FT) is a novel tissue tracking technique developed for noninvasive assessment of myocardial motion and deformation. This preliminary study aimed to evaluate the observer’s reproducibility of CMR-FT in a small animal (mouse) model and define sample size calculation for future trials. Methods Six C57BL/6 J mice were selected from the ongoing experimental mouse model onsite and underwent CMR with a 3 Tesla small animal MRI scanner. Myocardial deformation was analyzed using dedicated software (TomTec, Germany) by two observers. Left ventricular (LV) longitudinal, circumferential and radial strain (EllLAX, EccSAX and ErrSAX) were calculated. To assess intra-observer agreement data analysis was repeated after 4 weeks. The sample size required to detect a relative change in strain was calculated. Results In general, EccSAX and EllLAX demonstrated highest inter-observer reproducibility (ICC 0.79 (0.46–0.91) and 0.73 (0.56–0.83) EccSAX and EllLAX respectively). In contrast, at the intra-observer level EllLAX was more reproducible than EccSAX (ICC 0.83 (0.73–0.90) and 0.74 (0.49–0.87) EllLAX and EccSAX respectively). The reproducibility of ErrSAX was weak at both observer levels. Preliminary sample size calculation showed that a small study sample (e.g. ten animals to detect a relative 10% change in EccSAX) could be sufficient to detect changes if parameter variability is low. Conclusions This pilot study demonstrates good to excellent inter- and intra-observer reproducibility of CMR-FT technique in small animal model. The most reproducible measures are global circumferential and global longitudinal strain, whereas reproducibility of radial strain is weak. Furthermore, sample size calculation demonstrates that a small number of animals could be sufficient for future trials

Measuring myocardial extracellular volume of the right ventricle in patients with congenital heart disease

The right ventricle ' s (RV) characteristics-thin walls and trabeculation-make it challenging to evaluate extracellular volume (ECV). We aimed to assess the feasibility of RV ECV measurements in congenital heart disease (CHD), and to introduce a novel ECV analysis tool. Patients (n=39) and healthy controls (n=17) underwent cardiovascular magnetic resonance T1 mapping in midventricular short axis (SAX) and transverse orientation (TRANS). Regions of interest (ROIs) were evaluated with regard to image quality and maximum RV wall thickness per ROI in pixels. ECV from plane ROIs was compared with values obtained with a custom-made tool that derives the mean T1 values from a "line of interest" (LOI) centered in the RV wall. In CHD, average image quality was good (no artifacts in the RV, good contrast between blood/myocardium), and RV wall thickness was 1-2 pixels. RV ECV was not quantifiable in 4/39 patients due to insufficient contrast or wall thickness= 1 pixel. T1 maps in SAX are recommended for RV ECV analysis. LOI application simplifies RV ECV measurements

Spontaneous Degenerative Aortic Valve Disease in New Zealand Obese Mice

Background: Degenerative aortic valve (AoV) disease and resulting aortic stenosis are major clinical health problems. Murine models of valve disease are rare, resulting in a translational knowledge gap on underlying mechanisms, functional consequences, and potential therapies. Naive New Zealand obese (NZO) mice were recently found to have a dramatic decline of left ventricular (LV) function at early age. Therefore, we aimed to identify the underlying cause of reduced LV function in NZO mice. Methods and Results: Cardiac function and pulmonary hemodynamics of NZO and age-matched C57BL/6J mice were monitored by serial echocardiographic examinations. AoVs in NZO mice demonstrated extensive thickening, asymmetric aortic leaflet formation, and cartilaginous transformation of the valvular stroma. Doppler echocardiography of the aorta revealed increased peak velocity profiles, holodiastolic flow reversal, and dilatation of the ascending aorta, consistent with aortic stenosis and regurgitation. Compensated LV hypertrophy deteriorated to decompensated LV failure and remodeling, as indicated by increased LV mass, interstitial fibrosis, and inflammatory cell infiltration. Elevated LV pressures in NZO mice were associated with lung congestion and cor pulmonale, evident as right ventricular dilatation, decreased right ventricular function, and increased mean right ventricular systolic pressure, indicative for the development of pulmonary hypertension and ultimately right ventricular failure. Conclusions: NZO mice demonstrate as a novel murine model to spontaneously develop degenerative AoV disease, aortic stenosis, and the associated end organ damages of both ventricles and the lung. Closely mimicking the clinical scenario of degenerative AoV disease, the model may facilitate a better mechanistic understanding and testing of novel treatment strategies in degenerative AoV disease

Biocompatibility control of a gelatin-PLGA-scaffold for cartilage regeneration in a rat model

Aufgrund des schlechten Eigenreparationspotentials des Gelenkknorpels führen Fehlbelastungen, Traumata und chronische entzündliche Erkrankungen des Gelenks oftmals zu progressiven Gelenkbeschwerden oder Arthrosen. Um die Regeneration von Knorpeldefekten zu unterstützen gibt es verschiedenste Ansätze in Therapie und Forschung. Bei der derzeit vielversprechendsten Methode werden Trägermaterialien (Scaffolds) in die Knorpeldefekte eingebracht, welche den Knorpelzellen Struktur und Stabilität beim Einwachsen in den Defekt bieten sollen. Nichtsdestotrotz bieten die meisten bisher erhältlichen Trägermaterialien nicht alle gewünschten Eigenschaften für eine effiziente Knorpelregeneration. Im Rahmen dieser Arbeit wurde deshalb ein neuartiges Trägermaterial, basierend auf Gelatine und PLGA, auf seine Biokompatibilität, im Rahmen einer Langzeitimplantationsstudie im Rattenmodell, getestet. Der Hälfte der insgesamt 84 weiblichen Wistar Ratten wurden die Gelatine-PLGA- Testimplantate subkutan implantiert, der anderen Hälfte die Ethisorb®Tamponade als Vergleichsimplantat mit bekannter Biokompatibilität. Nach unterschiedlich langen Zeitintervallen, zwischen 2 und 26 Wochen, wurde das Gewebe um die Implantate histologisch aufgearbeitet und die Gewebereaktion in Anlehnung an die DIN EN ISO 10993 ausgewertet und bewertet. Dabei zeigte sich, dass das Gelatine-Scaffold gut in die umgebende Subkutis integriert und bindegewebig durchwachsen wurde. Im Vergleich zum Kontrollmaterial Ethisorb® zeigte er eine schnellere Degradationsrate. So war das Gelatine-Scaffold nach 8 Wochen histologisch nicht mehr nachweisbar, während das Kontroll-Scaffold auch nach 26 Wochen noch histologisch erkennbar war. Im Vergleich zu dem bereits zugelassenen Kontroll-Scaffold verlief die Fremdkörperreaktion auf das zu untersuchenden Gelatine-PLGA-Scaffold ausgesprochen mild. Das Gelatine-PLGA- Scaffold weist also über den gesamten Versuchszeitraum eine gute Biokompatibilität auf. Je nach gewünschter Eigenschaft stellt das Gelatine- PLGA-Scaffold somit eine potenzielle, gut abbaubare und gewebeverträgliche Alternative zu den momentan erhältlichen Scaffolds dar.Cartilage has a limited capacity for repair. Inappropriate biomechanical stress and inflammatory diseases of the joint can result in progressive pain or osteoarthritis. There are various approaches to treatment and research to support the regeneration of cartilage. The most promising method adopts scaffolds into the cartilage defects. Ideally they would provide the cartilage with cells and offer stability for the ingrowth of new tissue. However, currently available scaffolds don’t offer all desired qualities for efficient cartilage regeneration. Therefore, a new scaffold based on gelatin and PLGA was tested for its biocompatibility over an extended time period in a rat model. This was compared against Ethisorb® Tamponade, an implant with well- known biocompatibility. Half of the total 84 female Wistar rats had the gelatin-PLGA-scaffold subcutaneously implanted, the other half the control. After various time intervals between 2 and 26 weeks the tissue around the implants was examined histologically and the foreign body reaction was evaluated according to DIN EN ISO 10993. The new scaffold was well integrated into the surrounding subcutaneous tissue and infiltrated with connective tissue. Compared to the control, the new scaffold showed improved resorption. Thus after 8 weeks the test item was no longer detectable histologically, while the control item was still histologically evident after 26 weeks. Compared to the control, the new scaffold caused a milder inflammatory response. The gelatin-PLGA-scaffold is a potential, biodegradable and biocompatible alternative to currently available scaffolds

Large Farm Animals Used for Research Purposes: A Survey on Purchase, Housing and Hygiene Management

Background: Farm animals (FAs) are frequently used in biomedical research. Recommendations for the purchase, housing and health monitoring of these animals (sheep, goats, cattle and pigs) are still missing, and many institutes have developed their own strategies and protocols to face the challenges associated with the use of farm animals. This may influence the comparability of research results and increase data variances, thus increasing animal use that contradicts the obligation to apply the 3Rs principle of reduction, refinement and replacement required in Directive 2010/63 EU and the German animal protection law. Methods: A survey was conducted to define the current state of the art in research institutes working with pigs, and large and small ruminants. Results: The results of the survey clearly show that there are no uniform procedures regarding the purchase, housing and hygiene management of farm animals contrary to small laboratory animals. The facilities make purpose-bound decisions according to their own needs and individual work instructions and implement their own useful protocols to improve and maintain the health of the animals. Conclusion: This survey was the first step to filling the gaps and identifying the status quo and practical applied measures regarding the purchase and hygiene monitoring of FAs in order to improve animal welfare and scientific validity

Buto, Ägypten. Aktuelle Arbeiten und Ausblicke. Die Arbeiten in den Jahren 2019 und 2020

Future research for the settlement site of Buto in the western Delta/Egypt is planned to focus on the settlement development during the Old Kingdom Period (ca. 2700–2200 BC), although corresponding field work cannot yet begin at this point. Nevertheless, preliminary work is under way, including various projects for the analysis and publication of the results obtained so far, especially of the Early Dynastic Period (ca. 3200–2700 BC) but also of the Third Intermediate and Late Period structures in Buto (ca. 950–525 BC)