Project description:To identify nasal cavity transcripts differentially expressed due to treatment with N, N-dimethyl-p-toluidine (DMPT), we collected RNA during the from male F344/N rats exposed to 120 mg/kg DMPT, 5 days after DMPT exposure for animals 5-6 weeks of age. These samples were interrogated with the Affymetrix Rat Genome 230 2.0 GeneChip Array. A total of 2,561 gene transcripts were differentially expressed due to DMPT treatment (false discovery rate (FDR) < 0.05).
Project description:Formaldehyde, an important industrial chemical, is used for multiple commercial purposes throughout the industrialized world. This simple, one carbon aldehyde is a natural metabolite formed in cells throughput the body. However, it is also a rodent nasal carcinogen, when inhaled by rats every day for two-years at irritant concentrations. High tumor incidences occur at concentration of 10 ppm and above; no tumors are observed at concentrations below 6.0 ppm. The US Environmental Protection Agency (US EPA) is now (2007) conducting a risk assessment to try to evaluate possible cancer risks for much lower levels of human exposure. Sensitive methods are needed to evaluate tissue responses below those concentrations that are clearly irritant or carcinogenic. This microarray study was undertaken to evaluate the mode of action for nasal responses to inhaled formaldehyde in Fisher 344 rats over a range of exposure concentrations. The range of concentrations used spanned those at which virtually no tissue responses were observed (0.7 ppm) to those that represent the highest concentration in the cancer studies (15 ppm) that produced nasal tumors in half the exposed group of rats. The study identified doses at which there were no statistically significant changes in gene expression; intermediate doses with changes in a small number of genes not easily grouped by function; and then concentrations where changes were consistent with irritation and cell stress responses. Experiment Overall Design: Eight week old male F344/NCrl rats were exposed to formaldehyde through either instillation or inhalation. For animals exposed via instillation, 40 ul per nostril of 400 mM formaldehyde was instilled intranasally. Vehicle control animals were instilled with 40 ul per nostril of distilled water. All animals exposed via instillation were sacrificed 6 hours post-exposure. For animals exposed via inhalation, whole-body exposures were performed at doses of 0, 0.7, 2, 6, and 15 ppm (6 hours per day, 5 days per week). Inhalation animals were sacrified at 6 hours, 24 hours, 5 days, and 19 days following initiation of exposure except for the 15 ppm concentration which was sacrificed at only the 6 hour time point. Following sacrifice, tissue from the Level II region of the nose was dissected and digested with a mixture of proteases to remove the epithelial cells. The epithelial cells scquired from this section of the nose consisted primarily of transitional epithelium with some respiratory epithelium. Microarray analysis was performed on the epithelial cells.
Project description:To identify nasal cavity transcripts differentially expressed due to treatment with N, N-dimethyl-p-toluidine (DMPT), we collected RNA during the from male F344/N rats exposed to 120 mg/kg DMPT, 5 days after DMPT exposure for animals 5-6 weeks of age. These samples were interrogated with the Affymetrix Rat Genome 230 2.0 GeneChip Array. A total of 2,561 gene transcripts were differentially expressed due to DMPT treatment (false discovery rate (FDR) < 0.05). There were 2 groups and 5x replication for each group, for 10 total samples. The groups were (1) DMPT and (2) vehicle control. We compared vehicle control vs DMPT using ORIOGEN software. The permutation based p-values for each test were significant for FDRâ¤5%.
Project description:Male Sprague-Dawley rats were used to establish exhausted-exercise model by motorized rodent treadmill. Yu-Ping-Feng-San at doses of 2.18 g/kg was administrated by gavage before exercise training for 10 consecutive days. Quantitative proteomics was performed for assessing the related mechanism of Yu-Ping-Feng-San.
Project description:d-serine is naturally present throughout the human body. It is also used as add-on therapy for treatment-refractory schizophrenia. d-Serine interacts with the strychnine-insensitive glycine binding site of NMDA receptor, and this interaction could lead to potentially toxic activity (i.e., excitotoxicity) in brain tissue. The transcriptomic changes that occur in the brain after d-serine exposure have not been fully explored. Affymetrix microarray technology was used to determine differential gene expression resulting from D-Serine exposure. Keywords: Dose course
Project description:To evaluate the differential impact of IFN-gamma secretion on nasal cavity epithelial cells, we compared the transcriptional profiles of nasal cavity epithelial cells (CD45-, CD3- CD11b-, CD31-, CD326+) from wildtype and IFN-gamma knockout mice at 30 days (d30) post intranasal infection with a live attenuated influenza virus expressing the immunodominant H-2Kd CD8 T cell epitope from Sendai virus nucleoprotein (LAIV-SenNP). Nasal cavity epithelial cells were also analyzed from LAIV-SenNP immunized wildtype and IFN-gamma knockout mice 3 days after intranasal administration of Sendai virus nucleoprotein peptide (d30+3). The results indicate that nasal cavity epithelial cells express genes associated with antigen presentation and antiviral function following antigen-specific T cell activation, and these alterations in transcriptional programming depend on IFN-gamma secretion.
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.