Research

Funding: Philipp Schwartz-Initiative, Alexander von Humboldt Foundation, 38.600 EUR

Project Details:
The aim of project is to gain deeper insights into how altered FSH secretion due to GnRH agonist SRI treatment affects FSHR expression, but also how it affects SSC self-renewal, differentiation and proliferation using the dog as a model.
SSC are crucial for male fertility as they sustain spermatogenesis, the continuous process of sperm production, ensuring the maintenance of reproductive function and genetic diversity. Understanding their regulation is essential for addressing fertility issues and reproductive medicine. Besides, the aim is to investigate to what extent the SSC niche is altered, namely how RA and RA generating enzymes are affected by altered peripheral FSH secretion.
For the current project dogs were treated over 5 months with a GnRH slow release implant (SRI); after 5 months the SRI was removed and groups of dogs were surgically castrated at the time of implant removal (week 0) and 3, 6, 9, 12 and 24 weeks later, respectively representing either downregulated/arrested spermatogenesis or restart of spermatogenesis at various time points. Besides, untreated healthy male and 2 month-old juvenile dogs served as controls. All samples have been previously characterised in detail within earlier projects.
As FSH is significantly reduced during downregulation and fully restored rapidly after SRI removal, these testicular samples collected during downregulation and subsequent recovery seem to be a promisining model to study effects of altered FSH signaling on SSCs and their niche in a non-rodent model.

Results:

https://pubmed.ncbi.nlm.nih.gov/39631561/

Funding: COVID-19-Forschungsnetzwerkes COFONI vom Niedersächsischen Ministerium für Wissenschaft und Kultur über die Universitätsmedizin Göttingen, 50.000 EUR

Project Details:
This project aims at
(1) Establish a database for BSL-3 sample biobanking from preclinical in vivo models of
COVID-19 disease within COFONI-network
(2) Initial review and meta-analysis of internationally available data on preclinical in vivo
models of COVID-19 disease

Project Details:
Animal welfare of pigs kept on farms includes both the well-being and the health of the animals. In Germany, there have been legal changes in relation to pig farming in recent years in order to achieve greater animal welfare. The study examines whether users inform themselves about topics concerning animal welfare in pig farming in Germany in forums and blogs and whether people with a professional background use these platforms to publish their personal opinions and evaluate emerging topics. For this purpose, the discussion content of Internet users with an obvious professional reference to pig farming is identified and their reaction to posts relating to animal welfare in pig farming is analyzed by means of a qualitative content analysis (Translated with DeepL.com (free version)).

Funding: FAPESP DGHT, 37.713 EUR

Project Details:
The study of the evolutionary processes that originate phenotypic diversity can offer insights into the process of adaptation in natural populations. Coloration patterns variation have intrigued scientists for centuries, and among vertebrates amphibians are one of the most interesting groups, exhibiting a vast variation in coloration, whose function has been mainly associated with UV protection, interspecies communication, and predator avoidance. Despite significant advances made on this topic, the genetic basis of coloration in amphibians is still surprisingly unknown. Herein we propose to deepen in genomic bases of coloration in the genus Brachycephalus, using the aposematic and polymorphic species B. actaeus as model. We are going to use transcriptomic data to identify genes, which are differentially expressed as well as histological sample for gathering information about chromatophore abundance and distribution among colour morphs in this species.

Cooperation Partners:

Prof. Dr. Célio Haddad, UNESP (Brazil)

Dr. Mariana Lyra, New York University, Abu Dhabi

Dr. Andrés Brunetti, Max Plank Institute for Chemical Ecology

Funding: MWK, 75.880 EUR

Project Details:
Circular RNAs regulating the SARS-CoV-2 infection in the cardiovascular system.

Results:

https://www.umg.eu/forschung/corona/cofoni/

Funding: Deutsche Forschungsgesellschaft (DFG), 398.333 EUR

Project Details:
Virus emergence and re-emergence is an increasing public health
problem as globalization and climate change promote the spread of
infectious disease. This is particularly true for mosquito-borne
infections as mosquitoes continue to spread to new geographic
regions. Alphaviruses such as Chikungunya virus (CHIKV) and
Venezuelan equine encephalitis virus (VEEV) belong to the group of
mosquito-borne viruses, which cause pathology in humans. The re-emerging CHIKV is causing long-lasting arthritis like symptoms, while
VEEV infection leads to encephalitis. Why the two viruses from the
same family cause pathologies in different tissues, i.e. joints versus
central nervous system (CNS), is unclear to date. This gap of
knowledge is reflected by the fact that few host factors for CHIKV and
VEEV are known. Here we capitalize on our findings that the
phosphatidylserine (PS) receptor T cell immunoglobulin mucin
receptor 1 (TIM-1) and a tetraspanin are host factors for CHIKV. We
hypothesize that (a) VEEV also hijacks PS receptors and tetraspanins
to infect human cells, (b) TIM-1 and the tetraspanin interact with
additional proteins to promote infection with CHIKV and possibly
VEEV and (c) that a subset of these host factors contribute to tissue
tropism of CHIKV and VEEV. To test our hypothesis we will initially
use unbiased state of the art quantitative proteomics methods to
identify entry factors and receptors of CHIKV and VEEV. Next we will
screen PS receptors and all 33 human tetraspanins for their role in
VEEV infection by RNA interference in human cells. TIM-1 and
Tetraspanin associated proteins will be identified by proximity labeling
in conjunction with high-resolution affinity enrichment mass
spectrometry. Finally we will investigate the contribution of the
identified host factors to tissue tropism of CHIKV and VEEV using
proteomics, single cell sequencing and virological methods.
Specifically, we will infect skin organotypic raft cultures and determine
the predominantly infected cell type as well as expression levels of
identified host factors in the susceptible versus refractory cells.
Additionally we will integrate expression data from online repositories
and measure proteomes of relevant cell types including fibroblasts
and neuronal cells. Using feature selection approaches, we will
identify host factors, which likely contribute to the distinct tissue
tropism and pathologies caused by CHIKV and VEEV. These host
factors will be systematically knocked out first in relevant cell types
and then in mice to delineate the contribution to disease manifestation
in vitro and in vivo. Taken together, this research program aims at
providing mechanistic insight into the infection processes caused by
two important human pathogens, CHIKV and VEEV. The results will
help understand disease mechanisms and may ultimately reveal drug
targets for therapeutic intervention with Chikungunya fever and
Venezuelan equine encephalitis.

Funding: #

Project Details:
The decline in insect biodiversity with negative consequences for food webs and the loss of ecosystem services is currently dramatic. The causes of the decline in insect diversity are manifold, the qualitative deterioration of their habitats, whether on land or in water, light pollution, habitat loss, competition from invasive species and environmental toxins are just some of the factors. As part of this pilot project, flowering areas and nesting aids for insects are being created on the grounds of the University of Veterinary Medicine Hannover Foundation. The results of a species inventory serve as the basis for targeted measures to improve the habitat. The optimizations, e.g. the creation of flowering areas with regional wildflowers, deadwood areas and insect nesting aids, are only the first steps.
Through these measures to promote key species groups, such as wild bees and butterflies, other groups of organisms can also be promoted through deadweight effects due to the improved structural offer, in order to achieve a sustainable optimization of the entire TiHo site.
Further steps are planned as part of the project, which will be scientifically supported by Bachelor's and Master's theses. The TiHo grounds, which are near-natural in many areas, already provide important habitats for numerous rare animals and plants in the urban environment. These habitats are to be recorded in detail, protected and optimized. Other planned measures include improving the ecological condition of the Bünte pond in the park, creating an interactive insect trail and an exhibition with measures to promote biodiversity in urban areas.

Funding: Verein der Förderer der Wildtierforschung e.V., 5.800 EUR

Project Details:
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Cooperation Partners:

Chadi Touma, Abteilung Verhaltensbiologie, Universität Osnabrück

Funding: Drittmittelprojekt, gefördert durch die Fritz-Ahrberg-Stiftung., 20.000 EUR

Project Details:
Alternative sources of nitrite or nitrate for meat product production are the subject of much current research. Since nitrite is an important additive that can be used to generate the desired cured red in meat products, and thus an appealing and stable color for the consumer, it is considered largely indispensable. While there are efforts to generate nitrite-free or -reduced products due to health concerns, these are generally characterized by a less vibrant color as well as a shorter shelf life.
Nitrite is commonly added to meat products as a mixture of nitrite ions (sodium or potassium nitrite) and table salt (synthetic nitrite curing salt (NPS)). This is countered by the growing consumer demand for meat products made using natural substances. Plant extracts, for example, which naturally contain nitrate, come into question here. This nitrate can be converted to nitrite in the production process with the aid of a starter culture. The nitrite generated in this way can subsequently induce the curing process.
In addition to plant extracts, drinking water can also be used as a source of nitrite or nitrate. If drinking water is treated with non-thermal plasma, nitrogen species (including nitrate and nitrite) are formed in the liquid. The amounts and compositions of these nitrogenous species vary depending on the plasma source, settings and treatment durations. Thanks to the kind support of the Fritz Ahrberg Foundation, we were able to purchase a plasma source in early 2021 and use it to produce plasma-activated water (PAW) for the first time. The first results showed that both nitrite and nitrate can be generated in, for a curing process, sufficient quantities. The plant available to us generates mainly nitrate ions. These could be successfully converted into nitrite by adding a nitrate-reducing starter culture in an in vitro experiment for the production of a cooked sausage product. Thus, a curing process using PAW could be successfully induced.
In addition to the direct incorporation of PAW into the browning substance in the production of cooked sausage, the use of this novel nitrate or nitrite source is also of interest for the wet curing of meat products. This research project therefore aims to gather initial knowledge on whether PAW can induce a reddening process without the addition of synthetic nitrite during the wet curing of meat products and what criteria must be met to generate an acceptable product. Possible other positive or negative effects on the product and its shelf life will be investigated and critically discussed. Physicochemical, sensory and microbiological investigations are planned for this purpose.

Funding: Drittmittelprojekt, gefördert durch den Forschungskreis der Ernährungsindustrie e.V. (FEI), 206.756 EUR

Project Details:
Sodium chloride (NaCl) is used for the production of meat products such as raw sausages and cooked sausages, although there are health concerns regarding its use. In addition to techno-functional properties, NaCl not only affects the taste, but also the safety and shelf life of meat products, as NaCl contributes significantly to the hurdle concept by lowering water activity. The use of nitrite, in the form of nitrite curing salt, in meat products not only contributes to colour formation through reddening, flavour formation and antioxidant effects, but also unfolds an antimicrobial effect that leads to the inhibition of pathogenic or toxigenic bacteria such as Listeria (L.) monocytogenes and Clostridium (Cl.) botulinum. However, the consumption of heated meat products made with nitrite/nitrate carries the risk of ingesting nitrosamines, which are classified as carcinogenic. It is so far unclear what effects the individual and combined reductions of NaCl and nitrite really have with regard to shelf life and product safety in the meat products. This has to be considered especially against the background that the manufacturer is responsible for the safety of the product until the end of the best-before date and that food retailers want food with long shelf life. For this reason, in the present project at the Institute for Food Quality and Safety (LMQS), the content of NaCl and nitrite in raw sausages will be reduced, followed by analysis of their physicochemical (e.g. colour, pH value, aw value, shear force) and microbiological (e.g. total bacterial count) properties. The aim is to determine limit values which, when the salts are reduced, still lead to acceptable meat products for the industry. Taking into account the limit values, raw sausages (normal NaCl and nitrite contents, NaCl reduced, nitrite reduced, NaCl and nitrite reduced) will be produced by at least two industry partners in two repeats. After slicing the products will be packed under a protective gas atmosphere. These packages will be stored in the LMQS for up to 84 days, during which time they are regularly analysed physicochemically, microbiologically and, in the event of increased microbial content and/or spoilage, by next-generation sequencing (NGS). The aim is to identify typical (new) bacterial species (indicator germs) that are associated with the shelf life/ spoilage of raw sausages from industrial production. In addition, molecular biological methods for the detection of these indicator germs will also be developed. Finally, challenge tests will be carried out on packaged raw sausages with different NaCl- and nitrite-concentrations after inoculation with the detected indicator germ and Cl. sporogenes, a surrogate of Cl. botulinum. The aim is to determine the behaviour of these bacterial species in or on raw sausages with different NaCl and nitrite contents.

Cooperation Partners:

Deutsches Institut für Lebensmitteltechnik (DIL) in Quakenbrück