240 research outputs found
Untangling cellular and molecular mechanisms of fibrotic disease
Tissue fibrosis, or scar formation, is the common final pathway of virtually all chronic diseases and affects nearly every organ, including kidney, heart, lung, bone marrow and liver, among others. Myofibroblasts are the cells that cause fibrosis but their cellular origin has been controversial and their mechanism of activation has been unclear. We have identified Gli1+ cells as a major source of fibrosis driving myofibroblasts and demonstrated that GLi2 protein is a major driver of their expansion. Genetic ablation of these cells ameliorates fibrosis and rescues organ function. Pharmacologic inhibition of Gli proteins halts myofibroblast cell-cycle progression and ameliorates fibrosis. In conclusion our data indicates that Gli1+ perivascular cells are a promising therapeutic target in fibrosis
Understanding deregulated cellular and molecular dynamics in the haematopoietic stem cell niche to develop novel therapeutics for bone marrow fibrosis
Bone marrow fibrosis is the continuous replacement of blood-forming cells in the bone marrow with excessive scar tissue, leading to failure of the body to produce blood cells and ultimately to death. Myofibroblasts are fibrosis-driving cells and are well characterized in solid organ fibrosis, but their role and cellular origin in bone marrow fibrosis have remained obscure. Recent work has demonstrated that Gli1+ and leptin receptor+ mesenchymal stromal cells are progenitors of fibrosis-causing myofibroblasts in the bone marrow. Genetic ablation or pharmacological inhibition of Gli1+ mesenchymal stromal cells ameliorated fibrosis in mouse models of myelofibrosis. Conditional deletion of the platelet-derived growth factor (PDGF) receptor-α (PDGFRA) gene (Pdgfra) and inhibition of PDGFRA by imatinib in leptin receptor+ stromal cells suppressed their expansion and ameliorated bone marrow fibrosis. Understanding the cellular and molecular mechanisms in the haematopoietic stem cell niche that govern the mesenchymal stromal cell-to-myofibroblast transition and myofibroblast expansion will be critical to understand the pathogenesis of bone marrow fibrosis in both malignant and non-malignant conditions, and will guide the development of novel therapeutics. In this review, we summarize recent discoveries of mesenchymal stromal cells as part of the haematopoietic niche and as myofibroblast precursors, and discuss potential therapeutic strategies in the specific targeting of fibrotic transformation in bone marrow fibrosis
Cardiac remodeling in chronic kidney disease
Cardiac remodeling occurs frequently in chronic kidney disease patients and affects quality of life and survival. Current treatment options are highly inadequate. As kidney function declines, numerous metabolic pathways are disturbed. Kidney and heart functions are highly connected by organ crosstalk. Among others, altered volume and pressure status, ischemia, accelerated atherosclerosis and arteriosclerosis, disturbed mineral metabolism, renal anemia, activation of the renin-angiotensin system, uremic toxins, oxidative stress and upregulation of cytokines stress the sensitive interplay between different cardiac cell types. The fatal consequences are left-ventricular hypertrophy, fibrosis and capillary rarefaction, which lead to systolic and/or diastolic left-ventricular failure. Furthermore, fibrosis triggers electric instability and sudden cardiac death. This review focuses on established and potential pathophysiological cardiorenal crosstalk mechanisms that drive uremia-induced senescence and disease progression, including potential known targets and animal models that might help us to better understand the disease and to identify novel therapeutics
Petrophysical zoning elements of Chertovo Koryto gold-ore deposit (Patom Upland, Eastern Siberia)
The paper considers magnetic susceptibility (chi) and electrode potentials (EP) of rocks in the Chertovo Koryto deposit. Carbon-bearing substance is found in all the studied samples, but in some cases, this substance supplies EP (-150 ± -400 mV). In these samples [chi] rarely exceeds 40·10{-5} SI units, while, in other samples [chi] is 8-10 (up to 30) times higher. Less intensive EP (-20 ± -240 mV) is furnished due to the sulfides in this deposit. Rocks with polarized carbon-bearing substance do not contain magnetic pyrrhotine and are negative linear EP anomalies. Rocks in which carbon-bearing substance is associated with pyrrhotine are revealed as magnetic anomalies. The adjacent rocks determine petrophysical zoning of the Chertovo Koryto deposit. The combination of negative linear EP anomalies and magnetic anomalies is a potential indicator and can define the multi-stage formation of the deposit itself
Vitamin K2 Needs an RDI Separate from Vitamin K1
Vitamin K and its essential role in coagulation (vitamin K [Koagulation]) have been well established and accepted the world over. Many countries have a Recommended Daily Intake (RDI) for vitamin K based on early research, and its necessary role in the activation of vitamin K-dependent coagulation proteins is known. In the past few decades, the role of vitamin K-dependent proteins in processes beyond coagulation has been discovered. Various isoforms of vitamin K have been identified, and vitamin K2 specifically has been highlighted for its long half-life and extrahepatic activity, whereas the dietary form vitamin K1 has a shorter half-life. In this review, we highlight the specific activity of vitamin K2 based upon proposed frameworks necessary for a bioactive substance to be recommended for an RDI. Vitamin K2 meets all these criteria and should be considered for a specific dietary recommendation intake
Big science and big data in nephrology
There have been tremendous advances during the last
decade in methods for large-scale, high-throughput data
generation and in novel computational approaches to
analyze these datasets. These advances have had a
profound impact on biomedical research and clinical
medicine. The field of genomics is rapidly developing
toward single-cell analysis, and major advances in
proteomics and metabolomics have been made in recent
years. The developments on wearables and electronic
health records are poised to change clinical trial design.
This rise of ‘big data’ holds the promise to transform not
only research progress, but also clinical decision making
towards precision medicine. To have a true impact, it
requires integrative and multi-disciplinary approaches that
blend experimental, clinical and computational expertise
across multiple institutions. Cancer research has been at
the forefront of the progress in such large-scale initiatives,
so-called ‘big science,’ with an emphasis on precision
medicine, and various other areas are quickly catching up.
Nephrology is arguably lagging behind, and hence these
are exciting times to start (or redirect) a research career to
leverage these developments in nephrology. In this review,
we summarize advances in big data generation,
computational analysis, and big science initiatives, with a
special focus on applications to nephrology
Host taxon-derived Sarcoptes mite in European wild animals revealed by microsatellite markers
Ten markers specific to Sarcoptes mites were used in applying microsatellite genotyping to individual Sarcoptes mites collected in three European countries from 15 wild mammal populations belonging to 10 host species. The results showed that geographical separation had real biological significance for the definition of mite sub-populations, and that the degree of genetic exchange occurring between mites from different localities was apparently related to the geographical distance between locations. Wild host-derived mite populations were found to be clustered into three main groups: herbivore-, carnivore- and omnivore-derived Sarcoptes populations, with the omnivore-derived group located halfway between the herbivore- and carnivore-derived Sarcoptes populations. The separation between these three mite groups was better supported than the geographical separations; nevertheless, a kind of sub-clustering was detected within each of these three groups that separates mite populations into their geographical localities (countries). The lack of gene flow between Sarcoptes populations may have improved parasitic adaptations and led to what we refer to as a host-taxon-derived (carnivore host-, herbivore host- and omnivore host-derived) Sarcoptes mite found on European wild animals. Our results demonstrate that Sarcoptes is not a single panmictic population, even within each geographical location. This finding will have important ramifications for the study of the genetic structure of populations, life cycles, diagnosis and the monitoring protocols of the ubiquitous Sarcoptes mite, and could thus contribute to a better understanding of its associated epidemiology, which is of pivotal interest for wildlife biological conservation. © 2010 Elsevier Ltd. All rights reserved.Peer Reviewe
Lack of evidence does not justify neglect. how can we address unmet medical needs in calciphylaxis
Calcific uraemic arteriolopathy (CUA), or calciphylaxis, is a rare disease predominantly occurring in comorbidity with dialysis. Due to the very low frequency of CUA, prospective studies on its management are lacking and even anecdotal reports on treatment remain scarce. Therefore, calciphylaxis is still a challenging disease with dismal prognosis urgently requiring adequate strategies for diagnosis and treatment.In an attempt to fill some of the current gaps in evidence on various, highly debated and controversial aspects of dialysis-associated calciphylaxis, 13 international experts joined the 1st Consensus Conference on CUA, held in Leuven, Belgium on 21 September 2015. The conference was supported by the European Calciphylaxis Network (EuCalNet), which is a task force of the ERA-EDTA scientific working group on Chronic Kidney Disease-Mineral and Bone Disorders (CKD-MBD). After an intense discussion, a 9-point Likert scale questionnaire regarding 20 items on calciphylaxis was anonymously answered by each participant. These 20 items addressed unsolved issues in terms of diagnosis and management of calciphylaxis. On the one hand, the analysis of the expert opinions identified areas of general consensus, which might be a valuable aid for physicians treating such a disease with less experience in the field. On the other hand, some topics such as the pertinence of skin biopsy and administration of certain treatments revealed divergent opinions. The aim of the present summary report is to provide some guidance for clinicians who face patients with calciphylaxis in the current setting of absence of evidence-based medicin
- …