Project description:Thyroid autonomy is a frequent cause of thyrotoxicosis in regions with iodine deficiency. Epidemiological data suggest that the prevalence of thyroid autonomy is not only inversely correlated with the ambient iodine supply, but that iodide may also influence the course of pre-existing thyroid autonomy with possibly different effects on thyroid growth and function. Iodine slows TSH effects on thyroid growth stimulation and this effect is more pronounced in thyrocytes with constitutive cAMP activation i.e. in thyroid autonomy. Iodine induced growth alteration in early stage thyroid autonomy is conferred by induction of apoptosis and G2/M arrest. Transcriptome analysis revealed significant modulation of gene networks relevant to cell adhesion, cadherin signalling and ion binding with more pronounced effects in constitutively active FRTL-5 cells compared to normal FRTL-5 cells.
Project description:Thyroid autonomy is a frequent cause of thyrotoxicosis in regions with iodine deficiency. Epidemiological data suggest that the prevalence of thyroid autonomy is not only inversely correlated with the ambient iodine supply, but that iodide may also influence the course of pre-existing thyroid autonomy with possibly different effects on thyroid growth and function. Iodine slows TSH effects on thyroid growth stimulation and this effect is more pronounced in thyrocytes with constitutive cAMP activation i.e. in thyroid autonomy. Iodine induced growth alteration in early stage thyroid autonomy is conferred by induction of apoptosis and G2/M arrest. Transcriptome analysis revealed significant modulation of gene networks relevant to cell adhesion, cadherin signalling and ion binding with more pronounced effects in constitutively active FRTL-5 cells compared to normal FRTL-5 cells. The aim was to study iodide-induced changes in global gene expression in an in vitro model of thyroid autonomy. This model makes use of FRTL-5 cells with stable expression of a constitutively activating TSH receptor mutation or wild type TSHR as a control.
Project description:The inhibitory effect of supra physiological iodide concentrations on thyroid hormone synthesis (Wolff-Chaikoff effect) and thyrocyte proliferation is largely know as iodine autoregulation. However, the molecular mechanisms by which iodide excess modulate thyroid functions remains unclear. In this work, we analyzed the rat follicular cell PCCl3 transcriptome profile under untreated and treated conditions with 10-3M sodium iodide (Na/I). Serial Analysis of Gene Expression revealed several transcripts differentially expressed in response to the iodide showing that excess iodide affects almost all aspects of thyroid cell function and differentiation acting on the iodine autoregulatory mechanism through a complex process. Keywords: comparative genomic analysis
Project description:The inhibitory effect of supra physiological iodide concentrations on thyroid hormone synthesis (Wolff-Chaikoff effect) and thyrocyte proliferation is largely know as iodine autoregulation. However, the molecular mechanisms by which iodide excess modulate thyroid functions remains unclear. In this work, we analyzed the rat follicular cell PCCl3 transcriptome profile under untreated and treated conditions with 10-3M sodium iodide (Na/I). Serial Analysis of Gene Expression revealed several transcripts differentially expressed in response to the iodide showing that excess iodide affects almost all aspects of thyroid cell function and differentiation acting on the iodine autoregulatory mechanism through a complex process. Keywords: comparative genomic analysis PCCl3 cells were cultured under untreated and treated conditions with 10-3M NaI during 24 hours
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.