The epidermal circadian clock integrates and subverts brain signals to guarantee skin homeostasis.

In mammals, the circadian clock network drives daily rhythms of tissue-specific homeostasis. To dissect daily inter-tissue communication, we constructed a mouse minimal clock network comprising only two nodes: the peripheral epidermal clock and the central brain clock. By transcriptomic and functional characterization of this isolated connection, we identified a gatekeeping function of the peripheral tissue clock with respect to systemic inputs. The epidermal clock concurrently integrates and subverts brain signals to ensure timely execution of epidermal daily physiology. Timely cell-cycle termination in the epidermal stem cell compartment depends upon incorporation of clock-driven signals originating from the brain. In contrast, the epidermal clock corrects or outcompetes potentially disruptive feeding-related signals to ensure the optimal timing of DNA replication. Together, we present an approach for cataloging the systemic dependencies of daily temporal organization in a tissue and identify an essential gate-keeping function of peripheral circadian clocks that guarantees tissue homeostasis.

Investigation of Toxoplasma gondii, Neospora caninum and Tritrichomonas foetus in abortions of cattle, sheep and goats in Turkey: Analysis by real-time PCR, conventional PCR and histopathological methods.

The aim of this study was to identify Neosopora caninum, Toxoplasma gondii and Tritricomonas foetus in all cattle aborted fetus samples and N. caninum and T. gondii in sheep and goat aborted fetuses sent to Elazig Veterinary Control Institute during two years. Total genomic DNAs were obtained using a commercial kit. Real-time PCR analysis was performed separately for each agent. Conventional PCR was set up for confirmation of positive samples. Then, fetal brain, heart, lung and liver samples were analysed by hematoxylin-eosin (HE) and Avidin-Biotin Complex (ABC) Immunohistochemistry (IHC) methods. Totally, we tested 55 aborted fetus samples. Of these samples, seven (12.7 %) was belonged to goats, 18 (32.7 %) to sheep and 30 (54.5 %) to cattle. T. gondii was detected in six (10.90 %) samples, and four (7.27 %) of them were positive with Real-time PCR, while only one of these four samples was positive for both classical PCR and IHC. N. caninum was determined by at least one of the three tests in 14 (25.45 %) of the samples studied, while 8 (14.54 %) of the positive samples were detected by Real-time PCR, only two of them were also positive with conventional PCR, eight (14.54 %) samples was determined as positive by IHC. Considering T. foetus in the samples, positivity was determined in two (3.63 %) of 55 aborted fetus (both of which were aborted cattle fetus) by Real-time PCR, while only one of them was positive with conventional PCR, while no positivity was detected with the IHC.