Distribution, causal agents, and infection dynamic of emerging ink disease of sweet chestnut in Southern Switzerland

DATA AVAILABILITY STATEMENT : The data that support the findings of this study are available from the corresponding author upon reasonable request.Emerging diseases caused by both native and exotic pathogens represent a main threat to forest ecosystems worldwide. The two invasive soilborne pathogens Phytophthora cinnamomi and Phytophthora cambivora are the causal agents of ink disease, which has been threatening Castanea sativa in Europe for several centuries and seems to be re-emerging in recent years. Here, we investigated the distribution, causal agents, and infection dynamics of ink disease in southern Switzerland. A total of 25 outbreaks were identified, 19 with only P. cinnamomi, 5 with only P. cambivora, and 1 with both species. Dendrochronological analyses showed that the disease emerged in the last 20–30 years. Infected trees either died rapidly within 5–15 years post-infection or showed a prolonged state of general decline until death. Based on a generalized linear model, the local risk of occurrence of ink disease was increased by an S-SE aspect of the chestnut stand, the presence of a pure chestnut stand, management activities, the proximity of roads and buildings, and increasing annual mean temperature and precipitation. The genetic structure of the local P. cinnamomi population suggests independent introductions and local spread of the pathogen.Swiss Federal Office for the Environment; Program of international territorial cooperation INTERREG VA Italia-Svizzera 2014/2020 (Project MONGEFITOFOR); The forest service of the cantons Ticino and Grisons.http://wileyonlinelibrary.com/journal/emiam2024Forestry and Agricultural Biotechnology Institute (FABI)SDG-15:Life on lan

The RSPO–LGR4/5–ZNRF3/RNF43 module controls liver zonation and size

LGR4/5 receptors and their cognate RSPO ligands potentiate Wnt/β-catenin signalling and promote proliferation and tissue homeostasis in epithelial stem cell compartments. In the liver, metabolic zonation requires a Wnt/β-catenin signalling gradient, but the instructive mechanism controlling its spatiotemporal regulation is not known. We have now identified the RSPO-LGR4/5-ZNRF3/RNF43 module as a master regulator of Wnt/β-catenin-mediated metabolic liver zonation. Liver-specific LGR4/5 loss of function (LOF) or RSPO blockade disrupted hepatic Wnt/β-catenin signalling and zonation. Conversely, pathway activation in ZNRF3/RNF43 LOF mice or with recombinant RSPO1 protein expanded the hepatic Wnt/β-catenin signalling gradient in a reversible and LGR4/5-dependent manner. Recombinant RSPO1 protein increased liver size and improved liver regeneration, whereas LGR4/5 LOF caused the opposite effects, resulting in hypoplastic livers. Furthermore, we show that LGR4(+) hepatocytes throughout the lobule contribute to liver homeostasis without zonal dominance. Taken together, our results indicate that the RSPO-LGR4/5-ZNRF3/RNF43 module controls metabolic liver zonation and is a hepatic growth/size rheostat during development, homeostasis and regeneration

Master thesis: Study of the Yap-Hippo and Wnt Pathways for Intestinal Regeneration in an Ex Vivo Small Intestinal 3D Organoid Model. Hochschule Mannheim.

Tissue regeneration plays a crucial role in epithelial wound healing, such as the intestinal epithelium following cancer therapy. Cancer patients often suffer from very painful mucositis in the oral cavity and the intestine in response to radiation therapy. Epithelial regeneration is driven by stem cells, and this process is impaired in following radiation. The Wnt pathway constitutes a key player of stem cell activity, and interaction of Wnt and Yap signaling pathways are thought to act in a sensitive balance during epithelial wound healing. However, the molecular interactions and roles of both pathways during intestinal regeneration are still not clear. In the present study the impact of Yap pathway on the stem cell proliferation controlling Wnt signaling was investigated. Three dimensional ex vivo models of murine small intestinal organoids were used to investigate stem cells in their physiological environment. The effect of Yap absence on Wnt signaling was studied by deletion of Yap in organoids. To do so, transient transfection methods like lipofection and electroporation needed first to be established for the primary multicellular organoids. Since these transient transfection methods showed sub-optimal efficiency, an approach to inducible delete Yap via adeno associated virus- and adenovirus-mediated gene transfer was applied. Results of this project provided no evidence of direct Yap pathway influence on Wnt target gene expression

PhD Thesis: Technologies for Vascularized Skin Equivalents to Study Cutaneous Wound Healing in Vitro

PhD Thesis, Lisa Kiesewetter, "Technische Fakultät der Friedrich-Alexander-Universität Erlangen-Nürnberg zur Erlangung des Doktorgrades Dr.-Ing." University of Erlangen-Nürnberg, Germany. Some of the work mentioned in the thesis are based on a Master Service Agreement of NIBR with the Fraunhofer Institute, dated August 14, 2015, aimed at a publication for the establishment of an in vitro skin model (exchange of protocols, reagents, positive control recombinant growth factor IGF-1). Due to lack of efficacy of the tested agents in the models, the data have not been submitted for publication. The NIBR contributions are mentioned on the following sections of the thesis: Methods: pp. 66-67 Results: pp. 88-94 Discussion: pp. 151-152 Appendix: p. 203 Acknowledgements: p. 211 The two NVS employees mentioned below are acknowledged in the thesis, but they are not authors. The models presented in this thesis should provide new, sophisticated alternatives for animal experiments in the field of research on cutaneous wound healing. Novel active pharmaceutical ingredients can be studied employing wound models meeting the specific experimental needs and biological complexity, while not solely restricted to biochemical and histological readout parameters

Molecular characterization of chronic cutaneous wounds reveals subregion- and wound type-specific differential gene expression.

A limited understanding of the pathology underlying chronic wounds has hindered the development of effective diagnostic markers and pharmaceutical interventions. This study aimed to elucidate the molecular composition of various common chronic ulcer types to facilitate drug discovery strategies. We conducted a comprehensive analysis of leg ulcers (LUs), encompassing venous and arterial ulcers, foot ulcers (FUs), pressure ulcers (PUs), and compared them with surgical wound healing complications (WHCs). To explore the pathophysiological mechanisms and identify similarities or differences within wounds, we dissected wounds into distinct subregions, including the wound bed, border, and peri-wound areas, and compared them against intact skin. By correlating histopathology, RNA sequencing (RNA-Seq), and immunohistochemistry (IHC), we identified unique genes, pathways, and cell type abundance patterns in each wound type and subregion. These correlations aim to aid clinicians in selecting targeted treatment options and informing the design of future preclinical and clinical studies in wound healing. Notably, specific genes, such as PITX1 and UPP1, exhibited exclusive upregulation in LUs and FUs, potentially offering significant benefits to specialists in limb preservation and clinical treatment decisions. In contrast, comparisons between different wound subregions, regardless of wound type, revealed distinct expression profiles. The pleiotropic chemokine-like ligand GPR15L (C10orf99) and transmembrane serine proteases TMPRSS11A/D were significantly upregulated in wound border subregions. Interestingly, WHCs exhibited a nearly identical transcriptome to PUs, indicating clinical relevance. Histological examination revealed blood vessel occlusions with impaired angiogenesis in chronic wounds, alongside elevated expression of genes and immunoreactive markers related to blood vessel and lymphatic epithelial cells in wound bed subregions. Additionally, inflammatory and epithelial markers indicated heightened inflammatory responses in wound bed and border subregions and reduced wound bed epithelialization. In summary, chronic wounds from diverse anatomical sites share common aspects of wound pathophysiology but also exhibit distinct molecular differences. These unique molecular characteristics present promising opportunities for drug discovery and treatment, particularly for patients suffering from chronic wounds. The identified diagnostic markers hold the potential to enhance preclinical and clinical trials in the field of wound healing

The use of skin models in drug development.

Three dimensional (3D) tissue models of the human skin are probably the most developed and understood in vitro engineered constructs. The motivation to accomplish organotypic structures was driven by the clinics to enable transplantation of in vitro grown tissue substitutes and by the cosmetics industry as alternative test substrates. Today a huge variety of 3D human skin models exist, covering a multitude of scientific and/or technical demands. This review summarizes and discusses different approaches to skin model development and sets them into the context of drug development. Although human skin models have become indispensable for the cosmetics industry, they have not yet started their triumphal procession in pharmaceutical research and development. For drug development these tissue models may be of particular interest for a) systemically acting drugs applied on the skin, and b) drugs acting at the site of application in the case of skin diseases or disorders. Although quite a broad spectrum of models covering different aspects of the skin as a biologically acting surface exists, these are most often single stand-alone approaches. In order to enable the comprehensive application into drug development processes, the approaches have to be synchronized to allow a cross-over comparison. Besides the development of biological relevant models, other issues are not less important in the context of drug development: standardized production procedures, process automation, establishment of significant analytical methods, and data correlation. For the successful, routine use of engineered human skin models in drug development, major requirements were defined. If these requirements can be accomplished in the next few years, human organotypic skin models will become indispensable for drug development too

Synthesis of a Series of Promising Isobenzofurans for the Reduction of Acute Mucositis Risk after Chemo- and Radiotherapy.

Mycophenolate mofelite (MMF), an immunosuppressant and prodrug of mycophenolic acid (MPA), is used extensively in transplant medicine and more specifically after bone marrow transplantation to prevent acute rejection and other severe complications such as mucositis. Despite extensive research, a mucositis-specific pain treatment has yet to be developed in order to improve the conditions of patients treated by chemo- and radiotherapy. Herein, we present the synthesis of a small series of isobenzofuran analogues identified during a screening campaign as possible mucositis mediators