43 research outputs found
Влияние моделей обратного тока насыщения диода на выходные характеристики двух-диодной модели солнечной батареи в среде Matlab Simulink
В работе проводилось моделирование солнечной батареи в программном обеспечении MATLAB Simulink. Изучались выходные параметры солнечной батареи в зависимости от модели обратного тока насыщения диода. Полученными результатами являются вольт-амперные и вольт-ваттные характеристики, показывающие влияние модели обратного тока насыщения диода на выходные параметры солнечной батареи.The work was carried out modeling of the solar battery in the software MATLAB Simulink. The output parameters of the solar battery were studied depending on the model of the reverse current saturation of the diode. The results are current-voltage and voltage-watt characteristics, showing the influence of the model of the inverse diode saturation current on the output parameters of the solar battery
Cross-Sample Validation Provides Enhanced Proteome Coverage in Rat Vocal Fold Mucosa
The vocal fold mucosa is a biomechanically unique tissue comprised of a densely cellular epithelium, superficial to an extracellular matrix (ECM)-rich lamina propria. Such ECM-rich tissues are challenging to analyze using proteomic assays, primarily due to extensive crosslinking and glycosylation of the majority of high Mr ECM proteins. In this study, we implemented an LC-MS/MS-based strategy to characterize the rat vocal fold mucosa proteome. Our sample preparation protocol successfully solubilized both proteins and certain high Mr glycoconjugates and resulted in the identification of hundreds of mucosal proteins. A straightforward approach to the treatment of protein identifications attributed to single peptide hits allowed the retention of potentially important low abundance identifications (validated by a cross-sample match and de novo interpretation of relevant spectra) while still eliminating potentially spurious identifications (global single peptide hits with no cross-sample match). The resulting vocal fold mucosa proteome was characterized by a wide range of cellular and extracellular proteins spanning 12 functional categories
Proteomic analysis of rat cartilage: the identification of differentially expressed proteins in the early stages of osteoarthritis
Identification of TGFβ-related genes regulated in murine osteoarthritis and chondrocyte hypertrophy by comparison of multiple microarray datasets
Objective: Osteoarthritis (OA) is a joint disease characterized by progressive degeneration of articular cartilage. Some features of OA, including chondrocyte hypertrophy and focal calcification of articular cartilage, resemble the endochondral ossification processes. Alterations in transforming growth factor β (TGFβ) signaling have been associated with OA as well as with chondrocyte hypertrophy. Our aim was to identify novel candidate genes implicated in chondrocyte hypertrophy during OA pathogenesis by determining which TGFβ-related genes are regulated during murine OA and endochondral ossification.
Methods: A list of 580 TGFβ-related genes, including TGFβ signaling pathway components and TGFβ-target genes, was generated. Regulation of these TGFβ-related genes was a
Optimised isolation method for RNA extraction suitable for RNA sequencing from feline teeth collected in a clinical setting and at post mortem
Advanced next generation sequencing approaches have started to reveal the cellular and molecular complexity of the microenvironment in many tissues. It is challenging to obtain high quality RNA from mineralised tissues. We developed an optimised method of RNA extraction from feline teeth collected in a clinical setting and at post mortem. Teeth were homogenised in phenol-guanidinium solution at near-freezing temperatures and followed by solid-phase nucleic acid extraction utilising a commercially available kit. This method produced good RNA yields and improved RNA quality based on RNA integrity numbers equivalent (RINe) from an average of 3.6 to 5.6. No correlation was found between RNA purity parameters measured by A260:280 or A230:260 ratios and degree of RNA degradation. This implies that RNA purity indicators cannot be reliably used as parameters of RNA integrity. Two reference genes (GAPDH, RPS19) showed significant changes in expression levels by qPCR at low and moderate RINe values, while RPL17 was stable at all RINe values tested. Furthermore, we investigated the effect of quantity and quality of RNA on the quality of the resultant RNA sequencing (RNA-Seq) data. Thirteen RNA-seq data showed similar duplication and mapping rates (94 to 95%) against the feline genome regardless of RINe values. However one low yield sample with a high RINe value showed a high duplication rate and it was an outlier on the RNA-seq multidimensional scaling plot. We conclude that the overall yield of RNA was more important than quality of RNA for RNA-seq quality control. These results will guide researchers who wish to perform RNA extractions from mineralised tissues, especially if collecting in a clinical setting with the recognised restraints that this imposes
213 EXPRESSION PROFILING OF MOUSE FEMORAL HEAD EXPLANT CULTURES AFTER STIMULATION WITH INTERLEUKIN-1α OR RETINOIC ACID
217 GLOBAL GENE EXPRESSION PROFILING OF EARLY OSTEOARTHRITIS IN WILD-TYPE MICE AND MICE LACKING ADAMTS-5 ACTIVITY
213 EXPRESSION PROFILING OF MOUSE FEMORAL HEAD EXPLANT CULTURES AFTER STIMULATION WITH INTERLEUKIN-1α OR RETINOIC ACID
Maintaining mRNA Integrity during Decalcification of Mineralized Tissues
Biomineralization of the extracellular matrix occurs inappropriately in numerous pathological conditions such as cancer and vascular disease, but during normal mammalian development calcification is restricted to the formation of the skeleton and dentition. The comprehensive study of gene expression in mineralized skeletal tissues has been compromized by the traditional decalcification/fixation methods that result in significant mRNA degradation. In this study we developed a novel RNAlater/EDTA decalcification method that protects the integrity of the mRNA in mature mouse tibial epiphyses. Furthermore, this method preserves the tissue structure to allow histological sectioning and microdissection to determine region-specific gene expression, in addition to immuno- and in situ histology. This method will be widely applicable to the molecular analysis of calcified tissues in various pathological conditions, and will be of particular importance in dissection of the gene expression in mouse bone and joint tissues during development and in important clinical conditions such as arthritis
Proteomic analysis of cartilage proteins
While the analysis of the cartilage proteome is important for our comprehensive understanding of the development and disease of this important tissue, several unique features of cartilage present some technical obstacles. Firstly, cartilage is difficult to obtain in adequate quantities for many protein analyses, especially from mice which are otherwise powerful experimental models. Furthermore, the cartilage extracellular matrix contains an insoluble network of collagen II-containing fibrils that are integrated within an abundant anionic network of aggrecan and hyaluronan aggregates. These interacting networks provide a structural scaffold for the covalent and non-covalent attachment of other proteins and glycoproteins. Consequently, proteomic analysis of cartilage requires extraction of proteins with chaotropic agents to achieve and significant protein solubilization. Finally, isolated chondrocytes are phenotypically unstable, which requires rapid isolation of cells or the use of specific culture conditions. Despite these problems, recent improvements in the sensitivity and reproducibility of two-dimensional electrophoresis (2-DE) and tandem mass spectrometry (MS/MS) techniques, combined with improved tissue preparation and sample pre-fractionation approaches, have made the proteomic characterization of cartilage tissues possible. Here we review the approaches that have been used and describe in detail protocols for the proteomic analysis of cartilage tissues and cells
