Similar Datasets
Project description:Type of experiment: Comparison of liver samples between sham (control) and 20% TBSA (total burn surface area) burn rats collected at 1h, 4h, 8h, and 24h. Experimental factors: Burn injury and time; Experiment design: All experimental liver samples collected after 1h, 4h, 8h, and 24h after burn injury were compared to a common reference (sham control treated as 0h time point); Bio source: Sprague-Drawley male rats weighing 150-200 g supplied through Charles river laboratories, MA (www.criver.com); Bio material manipulations: Rats (n=3 for each scald-burn and sham-burn time point) were individually housed in a temperature-controlled (25oC) and light-controlled room (12h light-dark cycle) and allowed to adjust to their new surroundings for at least 5 days prior to the experiment. Water and rat chow were provided ad libitum to the animals. On the day of the treatment, the animals were randomly divided into two groups, burned and sham-burned. The burn injury consisted of a full-skin-thickness scald burn of the dorsum, calculated to be ~ 20% of the ratâs total body surface area (TBSA), induced by immersing the designated area in boiling water for 10 s [Yamaguchi, 1997 #416]. Rats were resuscitated with an intra-peritoneal injection of sterile saline solution (1.5 mL/Kg body weight/% TBSA) immediately after burn. At each time point, three animals belonging to each group was sacrificed, the serum collected, and stored at â80oC. Hybridization extract: Total RNA was isolated from approximately 50 mg of pooled liver tissue using the Nucleospin II RNA isolation kit from Clontech (Palo Alto, CA), as per the manufacturerâs instructions. Labeling protocol: Labeling was performed as instructed by Affymetrix, Inc (www.affymetrix.com). In brief, 10 μg of total RNA was used for the double-stranded cDNA synthesis using the T7-oligo (dT) promoter primer kit (Affymetrix Inc.) and superscript RT II enzyme (Invitrogen). 1 μg of cDNA was labeled through invitro transcription reaction using T7 DNA polymerase in the presence of biotin labeled ribonucleotides. The cRNA was cleaned up using the Qiagen RNeasy columns following manufactures instructions. The cRNA (20 μg) was fragmented using the fragmentation buffer supplied as part of the Gene Chip Sample Cleanup Module (Affymetrix). Image analysis and raw data description: The images were analyzed using MAS V.0 software provided by Affymetrix, Inc. The raw data output consists of several metrices: Signal, Detection, Detection p-value, Stat pairs, Stat pairs used. Signal is a measure of the abundance of the transcript. Detection is call that indicates whether the transcript is detected (P, present), undetected (A, absent), or at the limit of detection (M, marginal). Detection p-value is a measure of the significance of the detection call. Stat pairs, is the number of probe pairs for a particular probe set on an array. Stat pairs used, is the number of probe pairs per probe set used in the analysis. Normalized and summarized data: All chips were scaled to a target intensity of 500 to account for differences between the replicate chips and their hybridization efficiencies using Affymetrix GENECHIP MAS V.0 software. The entire dataset is available at gene expression omnibus (http://www.ncbi.nlm.nih.gov/geo/) with the accession number GSE802. Three filters were serially used to obtain the list of annotated genes that demonstrated differential expression in intensity between sham and burn injured animals. In the first filter, only genes that were flagged as âpresentâ by the MAS V.0 analysis software in at least one of the time points in all replicate chips were considered for further analysis. This step eliminated all genes for which the expression data was not reproducible between the replicate chips. The genes that passed this criterion were subjected to a second filter where ANOVA was performed to test each gene independently for a statistical difference in expression between groups (0, 1, 4, 8 and 24 h). The output of the analysis is the probability (p value) that a difference in expression can be observed by chance i.e., probability of getting a false positive. While the occurrence of false positives can be controlled by choosing a higher significance level (0.01 or 0.001) it also concomitantly increases the false negatives. Therefore, in this study we have chosen to work with ANOVA p-value cut-off 0.05. To reduce the occurrence of the false positives, we have used the false discovery rate (FDR) method (33) which adjusts the ANOVA p-value (cut-off 0.05) while taking the dependencies between the genes into consideration. The 695 genes that demonstrated a significant ANOVA p-value were then selected and their expression values averaged. The third filter selected 339 genes that were either up-regulated or down-regulated by at least 2-fold between any one time point (1, 4, 8 or 24h) and the 0h time point (Sham control). To determine the temporal profiles in the data, gene expression values were hierarchically clustered using the dChip software (www.dChip.org). The expression values for a gene across all samples were standardized by setting the mean to 0 and standard deviation to 1. The software then builds a hierarchical cluster tree based on centroid-linkage method using Pearson correlation coefficient as the distance metric. A set of genes were assigned to cluster groups empirically based on visual inspection of their temporal expression patterns.
2007-10-11 | E-GEOD-802 | biostudies-arrayexpress
Project description:Animal experiments were performed with male Sprague-Dawley rats (Charles River Laboratories, Boston, MA) weighing 150 ? 200 grams. All experimental protocols used in this study were approved by the Subcommittee on Research Animal Care, Massachusetts General Hospital. Rats were individually housed in a temperature-controlled (25oC) and light-controlled room (12h light-dark cycle) and allowed to adjust to their new surroundings for at least 5 days prior to the experiment. Water and rat chow were provided ad libitum to the animals. On the day of the treatment, the animals were randomly divided into two groups, burned and sham-burned. The burn injury consisted of a full-skin-thickness scald burn of the dorsum, calculated to be ~ 20% of the rat?s total body surface area (TBSA), induced by immersing the designated area in boiling water for 10 s (45). Rats were resuscitated with an intra-peritoneal injection of sterile saline solution (1.5 mL/Kg body weight/% TBSA) immediately after burn. The mortality rate of this treatment was negligible. At each time point (1, 2, 4, and 7d), three animals belonging to each group were sacrificed, the liver and serum collected, and stored at ?80oC after being inflicted with 20% TBSA burn injury. Sham-burn rats (n=3) considered as the control were treated identically except that they were immersed into a 37oC water bath and immediately sacrificed to collect the livers.
2007-11-03 | E-GEOD-1860 | biostudies-arrayexpress
Project description:Few studies have assessed the patterns of parasite populations of rodents over a longitudinal gradient in Chile. In this work, the gastrointestinal helminthic fauna of invasive rodents in Chile was examined to assess the association between their presence/absence and abundance with latitude, host sex, and host body condition, and to assess the coexistence and correlation of the abundance between parasite species. Rodents were obtained from 20 localities between 33 and 43°S. Helminths were extracted from the gastrointestinal tract and identified morphologically. Overall, 13 helminth taxa were obtained. The most frequently identified parasite species was Heterakis spumosa, and the most abundant was Syphacia muris, while Physaloptera sp. was the most widely distributed. No locality presented with a coexistence that was different from that expected by chance, while the abundance of five helminthic species correlated with the abundance of another in at least one locality, most likely due to co-infection rather than interaction. Host sex was associated with parasite presence or abundance, and female sex-biased parasitism was notably observed in all cases. Body condition and latitude presented either a positive or negative association with the presence or abundance of parasites depending on the species. It is notable that the likely native Physaloptera sp. is widely distributed among invasive rodents. Further, gravid females were found, suggesting spillback of this species to the native fauna. The low frequency and abundance of highly zoonotic hymenolepid species suggest that rodents are of low concern regarding gastrointestinal zoonotic helminths.
| S-EPMC9277659 | biostudies-literature
Project description:This SuperSeries is composed of the SubSeries listed below.
2015-01-01 | GSE58692 | GEO
Project description:The Norway rat has important impacts on our life. They are amongst the most used research subjects, resulting in ground-breaking advances. At the same time, wild rats live in close association with us, leading to various adverse interactions. In face of this relevance, it is surprising how little is known about their natural behaviour. While recent laboratory studies revealed their complex social skills, little is known about their social behaviour in the wild. An integration of these different scientific approaches is crucial to understand their social life, which will enable us to design more valid research paradigms, develop more effective management strategies, and to provide better welfare standards. Hence, I first summarise the literature on their natural social behaviour. Second, I provide an overview of recent developments concerning their social cognition. Third, I illustrate why an integration of these areas would be beneficial to optimise our interactions with them.
| S-EPMC7145424 | biostudies-literature
Project description:BackgroundMurine kobuviruses (MuKV) are newly recognized picornaviruses first detected in murine rodents in the USA in 2011. Little information on MuKV epidemiology in murine rodents is available. Therefore, we conducted a survey of the prevalence and genomic characteristics of rat kobuvirus in Guangdong, China.ResultsFecal samples from 223 rats (Rattus norvegicus) were collected from Guangdong and kobuviruses were detected in 12.6% (28) of samples. Phylogenetic analysis based on partial 3D and complete VP1 sequence regions showed that rat kobuvirus obtained in this study were genetically closely related to those of rat/mouse kobuvirus reported in other geographical areas. Two near full-length rat kobuvirus genomes (MM33, GZ85) were acquired and phylogenetic analysis of these revealed that they shared very high nucleotide/amino acids identity with one another (95.4%/99.4%) and a sewage-derived sequence (86.9%/93.5% and 87.5%/93.7%, respectively). Comparison with original Aichivirus A strains, such human kobuvirus, revealed amino acid identity values of approximately 80%.ConclusionOur findings indicate that rat kobuvirus have distinctive genetic characteristics from other Aichivirus A viruses. Additionally, rat kobuvirus may spread via sewage.
| S-EPMC7161169 | biostudies-literature
Project description:Inflammation is a key component of pathological angiogenesis. Here we induce cornea neovascularisation using sutures placed into the cornea, and sutures are removed to induce a regression phase. We used whole transcriptome microarray to monitor gene expression profies of several genes
2016-08-18 | GSE81418 | GEO
Project description:Leptin and fractalkine: Novel subcutaneous cytokines in burn injury.
| PRJNA399105 | ENA
Project description:Individual differences in behaviors are seen across many species, and investigations have focused on traits linked to aggression, risk taking, emotionality, coping styles, and differences in cognitive systems. The current study investigated whether there were individual differences in proactive interference tasks in rats (Rattus Norvegicus), and tested hypotheses suggesting that these tasks should load onto a single factor and there should be clusters of rats who perform well or poorly on these tasks. The performance of 39 rats was tested across three learning tasks that all involved disengagement from an irrelevant previously learned stimulus to a relevant stimulus: latent inhibition (LI), partial reinforcement extinction effect (PREE), and reversal learning (RL). An exploratory factor analysis revealed the existence of one factor underlying performance. A cluster analysis revealed the existence of sets of rats displaying either weak LI and strong PREE and RL effects, or vice versa. These findings suggest that proactive interference may be based on a single underlying psychological system in rats.
| S-EPMC8858310 | biostudies-literature