185 research outputs found
Do Matrix Metalloproteases and Tissue Inhibitors of Metalloproteases in Tenocytes of the Rotator Cuff Differ with Varying Donor Characteristics?
An imbalance between matrix metalloproteases (MMPs) and the tissue inhibitors
of metalloproteases (TIMPs) may have a negative impact on the healing of
rotator cuff tears. The aim of the project was to assess a possible
relationship between clinical and radiographic characteristics of patients
such as the age, sex, as well as the degenerative status of the tendon and the
MMPs and TIMPs in their tenocyte-like cells (TLCs). TLCs were isolated from
ruptured supraspinatus tendons and quantitative Real-Time PCR and ELISA was
performed to analyze the expression and secretion of MMPs and TIMPs. In the
present study, MMPs, mostly gelatinases and collagenases such as MMP-2, -9 and
-13 showed an increased expression and protein secretion in TLCs of donors
with higher age or degenerative status of the tendon. Furthermore, the
expression and secretion of TIMP-1, -2 and -3 was enhanced with age, muscle
fatty infiltration and tear size. The interaction between MMPs and TIMPs is a
complex process, since TIMPs are not only inhibitors, but also activators of
MMPs. This study shows that MMPs and TIMPs might play an important role in
degenerative tendon pathologies
An Early Transcriptional Analysis of Fracture Hematoma in Rat
Among other stressors, age and mechanical constraints significantly influence
regeneration cascades in bone healing. Here, our aim was to identify genes
and, through their functional annotation, related biological processes that
are influenced by an interaction between the effects of mechanical fixation
stability and age. Therefore, at day three post-osteotomy, chip-based whole-
genome gene expression analyses of fracture hematoma tissue were performed for
four groups of Sprague-Dawley rats with a 1.5-mm osteotomy gap in the femora
with varying age (12 vs. 52 weeks - biologically challenging) and external
fixator stiffness (mechanically challenging). From 31099 analysed genes, 1103
genes were differentially expressed between the six possible combinations of
the four groups and from those 144 genes were identified as statistically
significantly influenced by the interaction between age and fixation
stability. Functional annotation of these differentially expressed genes
revealed an association with extracellular space, cell migration or
vasculature development. The chip-based whole-genome gene expression data was
validated by q-RT-PCR at days three and seven post-osteotomy for MMP-9 and
MMP-13, members of the mechanosensitive matrix metalloproteinase family and
key players in cell migration and angiogenesis. Furthermore, we observed an
interaction of age and mechanical stimuli in vitro on cell migration of
mesenchymal stromal cells. These cells are a subpopulation of the fracture
hematoma and are known to be key players in bone regeneration. In summary,
these data correspond to and might explain our previously described
biomechanical healing outcome after six weeks in response to fixation
stiffness variation. In conclusion, our data highlight the importance of
analysing the influence of risk factors of fracture healing (e.g. advanced
age, suboptimal fixator stability) in combination rather than alone
Proyecto de restauración de la casa del bosque, Buitrago de Lozoya
Proyecto de restauración de la casa del bosque, Buitrago de Lozoy
Virtual Valcamonica: collaborative exploration of prehistoric petroglyphs and their surrounding environment in multi-user virtual reality
In this paper, we present a novel, multi-user, virtual reality environment for the interactive, collaborative 3D analysis of large 3D scans and the technical advancements that were necessary to build it: a multi-view rendering system for large 3D point clouds, a suitable display infrastructure and a suite of collaborative 3D interaction techniques. The cultural heritage site of Valcamonica in Italy with its large collection of prehistoric rock-art served as an exemplary use case for evaluation. The results show that our output-sensitive level-of-detail rendering system is capable of visualizing a 3D dataset with an aggregate size of more than 14 billion points at interactive frame rates. The system design in this exemplar application results from close exchange with a small group of potential users: archaeologists with expertise in rock-art and allows them to explore the prehistoric art and its spatial context with highly realistic appearance. A set of dedicated interaction techniques was developed to facilitate collaborative visual analysis. A multi-display workspace supports the immediate comparison of geographically distributed artifacts. An expert review of the final demonstrator confirmed the potential for added value in rock-art research and the usability of our collaborative interaction techniques
Carbon usage in yellow‐fleshed Manihot esculenta storage roots shifts from starch biosynthesis to cell wall and raffinose biosynthesis via the myo‐inositol pathway
SUMMARY Cassava is a crucial staple crop for smallholder farmers in tropical Asia and Sub‐Saharan Africa. Although high yield remains the top priority for farmers, the significance of nutritional values has increased in cassava breeding programs. A notable negative correlation between provitamin A and starch accumulation poses a significant challenge for breeding efforts. The negative correlation between starch and carotenoid levels in conventional and genetically modified cassava plants implies the absence of a direct genomic connection between the two traits. The competition among various carbon pathways seems to account for this relationship. In this study, we conducted a thorough analysis of 49 African cassava genotypes with varying levels of starch and provitamin A. Our goal was to identify factors contributing to differential starch accumulation. Considering carotenoid levels as a confounding factor in starch production, we found that yellow‐ and white‐fleshed storage roots did not differ significantly in most measured components of starch or de novo fatty acid biosynthesis. However, genes and metabolites associated with myo ‐inositol synthesis and cell wall polymer production were substantially enriched in high provitamin A genotypes. These results indicate that yellow‐fleshed cultivars, in comparison to their white‐fleshed counterparts, direct more carbon toward the synthesis of raffinose and cell wall components. This finding is underlined by a significant rise in cell wall components measured within the 20 most contrasting genotypes for carotenoid levels. Our findings enhance the comprehension of the biosynthesis of starch and carotenoids in the storage roots of cassava.Significance Statement The development of high‐yielding cassava varieties with high‐carotenoid contents is an important goal in breeding to improve the nutritional value of the crop. However, high‐starch and high‐carotenoid levels are often inversely correlated. By comparing transcript and metabolite profiles of high‐starch and high‐carotenoid cassava storage roots, we found that the typically lower starch levels in high‐carotenoid genotypes are associated with increased carbon allocation toward myo‐inositol and cell wall component pathways.Bill and Melinda Gates Foundation http://dx.doi.org/10.13039/100000865Cluster of Excellence on Plant Sciences http://dx.doi.org/10.13039/10002270
Brain activity underlying negative self- and other-perception in adolescents: The role of attachment-derived self-representations
One of teenagers' key developmental tasks is to engage in new and meaningful relationships with peers and adults outside the family context. Attachment-derived expectations about the self and others in terms of internal attachment working models have the potential to shape such social reorientation processes critically and thereby influence adolescents' social-emotional development and social integration. Because the neural underpinnings of this developmental task remain largely unknown, we sought to investigate them by functional magnetic resonance imaging. We asked n = 44 adolescents (ages 12.01-18.84 years) to evaluate positive and negative adjectives regarding either themselves or a close other during an adapted version of the well-established self-other trait-evaluation task. As measures of attachment, we obtained scores reflecting participants' positive versus negative attachment-derived self- and other-models by means of the Relationship Questionnaire. We controlled for possible confounding factors by also obtaining scores reflecting internalizing/externalizing problems, schizotypy, and borderline symptomatology. Our results revealed that participants with a more negative attachment-derived self-model showed increased brain activity during positive and negative adjective evaluation regarding the self, but decreased brain activity during negative adjective evaluation regarding a close other, in bilateral amygdala/parahippocampus, bilateral anterior temporal pole/anterior superior temporal gyrus, and left dorsolateral prefrontal cortex. These findings suggest that a low positivity of the self-concept characteristic for the attachment anxiety dimension may influence neural information processing, but in opposite directions when it comes to self- versus (close) other-representations. We discuss our results in the framework of attachment theory and regarding their implications especially for adolescent social-emotional development and social integration
Correction to: Solve-RD: systematic pan-European data sharing and collaborative analysis to solve rare diseases
In the original publication of the article, consortium author list was missing in the article
Correction to: Solving patients with rare diseases through programmatic reanalysis of genome-phenome data
In the original publication of the article, consortium author lists were missing in the articl
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