Project description:Objective: To determine the effects of age and topographic location on gene expression in human neural retina. Methods: Macular and peripheral neural retina RNA were isolated from human donor eyes for DNA microarray and quantitative RTPCR analyses. Results: Total RNA from human donor retina preserved integrity. Hierarchic clustering analysis demonstrates the gene expression profiles of young, old, macula and peripheral retina cluster into four distinct groups. Genes which are highly expressed in macular, peripheral, young or old retina are identified, including inhibitors of Wnt Signaling Pathway (DKK1, FZD10 and SFRP2) shown preferably expressed in the periphery. Conclusions: The transcriptome of the human retina is affected by age and topographic location. Wnt pathway inhibitors in the periphery may maintain peripheral retinal cells in an undifferentiated state. Understanding the effects of age and topographic location on gene expression may lead to the development of new therapeutic interventions for age-related eye diseases. Twleve youang and older retinal macular or prepheral RNA samples are used for DNA microarray study to compare the effects of aging and anatomic location on gene expression in human retina.
Project description:Objective: To determine the effects of age and topographic location on gene expression in human neural retina. Methods: Macular and peripheral neural retina RNA were isolated from human donor eyes for DNA microarray and quantitative RTPCR analyses. Results: Total RNA from human donor retina preserved integrity. Hierarchic clustering analysis demonstrates the gene expression profiles of young, old, macula and peripheral retina cluster into four distinct groups. Genes which are highly expressed in macular, peripheral, young or old retina are identified, including inhibitors of Wnt Signaling Pathway (DKK1, FZD10 and SFRP2) shown preferably expressed in the periphery. Conclusions: The transcriptome of the human retina is affected by age and topographic location. Wnt pathway inhibitors in the periphery may maintain peripheral retinal cells in an undifferentiated state. Understanding the effects of age and topographic location on gene expression may lead to the development of new therapeutic interventions for age-related eye diseases.
2015-05-27 | GSE32614 | GEO
Project description:slope position
| PRJNA400258 | ENA
Project description:Soil microbial communities along a topographic gradient
Project description:H3.3G34R-mutant gliomas are lethal tumors of the cerebral hemispheres, with unknown mechanisms of topographic specificity and tumorigenicity. We developed a human embryonic stem cell (hESC)-based model of H3.3G34R-mutant glioma that recapitulates the anatomical and genetic characteristics of the patient tumors.
Project description:Biomaterials engineered to mimic extracellular matrix (ECM) topography play a pivotal role in tissue engineering. Previous research indicates that certain biomimetic topographies can guide stem cells towards multiple specific lineages. However, the mechanisms by which these topographic cues prime the multilineage differentiation remain largely elusive. In this study, we show that topography influences nuclear tension in MSCs through a mechanotransductive feedback mechanism, which in turn reshapes chromatin accessibility patterns, finally determines the stem cell lineage commitment. When cultured on an aligned substrate, MSCs show high cytoskeletal tension along the fibre direction, resulting in anisotropic nucleus tensile stress. This further leads to the opening of chromatin sites related to neurogenic, myogenic, and tenogenic genes by the regulation of transcription factors such as TLX. On the other hand, when MSCs are lied on a random substrate, they experience isotropic nucleus stress, leading to the opening of chromatin sites related to osteogenic and chondrogenic genes through the regulation of RUNX family transcription factors. Collectively, our results show that aligned and random topography induce site specific chromatin stretching and lineage specific gene expressing in MSCs, leading to their priming for specific lineages. Our study thus proposes a novel concept for topographic cues influencing on cell behavior and fate during tissue reconstitution and regeneration.
Project description:Although smoking-induced lung disease tends to be more common in the upper lobe, it is not known if this results from the skewed distribution of inhaled cigarette smoke or increased susceptibility of the upper lobes to these disorders. The distribution of inhaled cigarette smoke within the lung is complex, depending on lung pressure-volume relationships, gravity, individual smoking habits and the properties of the individual components of cigarette smoke. With the knowledge that the small airway epithelium is the earliest site of smoking-induced lung disease, and that the small airway epithelium is acutely sensitive to inhaled cigarette smoke with significant changes in the up- and down-regulation of hundreds of genes, we compared upper vs lower lobe gene expression in the small airway epithelium of the same cigarette smokers to determine if the gene expression patterns were similar or different. Active smokers (n=11) with early evidence of smoking-induced lung disease (normal spirometry but low diffusing capacity) underwent bronchoscopy and brushing of the small airway epithelium to compare upper vs lower lobe genome-wide gene expression assessed by microarray. Interestingly, cluster and principal component analysis demonstrated that, for each individual, the expression of the known small airway epithelium smoking-responsive genes were remarkably similar as upper vs lower lobe pairs, although, as expected, there were differences in the smoking-induced changes in gene expression from individual to individual. Thus, while there may be topographic differences in the distribution of cigarette smoke, sufficient smoke reaches the upper vs lower lobe small airway epithelium so that, within each smoker, the upper vs lower lobe gene expression are similar. These observations support the concept that the topographic differences in the occurrence of the smoking-induced lung diseases are likely secondary to topographic differences in the susceptibility of the upper vs lower lobes to cigarette smoke, not the topographic differences in distribution of inhaled cigarette smoke.
Project description:This project is based on visualizing the chemical and microbiological composition of individuals of Colostethus panamensis (Dendrobatidae), through the creation of a topographic map of the surface of their skin in 3D
2017-03-06 | MSV000080602 | MassIVE
Project description:Phylogenetic position of Nesodexia