The Trissin/TrissinR signaling pathway in the circadian network regulates evening activity in Drosophila melanogaster under constant dark conditions.

The circadian clock in Drosophila is governed by a neural network comprising approximately 150 neurons, known as clock neurons, which are intricately interconnected by various neurotransmitters. The neuropeptides that play functional roles in these clock neurons have been identified; however, the roles of some neuropeptides, such as Trissin, remain unclear. Trissin is expressed in lateral dorsal clock neurons (LNds), while its receptor, TrissinR, is expressed in dorsal neuron 1 (DN1) and LNds. In this study, we investigated the role of the Trissin/TrissinR signaling pathway within the circadian network in Drosophila melanogaster. Analysis involving our newly generated antibody against the Trissin precursor revealed that Trissin expression in the LNds cycles in a circadian manner. Behavioral analysis further demonstrated that flies with Trissin or TrissinR knockout or knockdown showed delayed evening activity offset under constant darkness conditions. Notably, this observed delay in evening activity offset in TrissinRNAi flies was restored via the additional knockdown of Ion transport peptide (ITP), indicating that the Trissin/TrissinR signaling pathway transmits information via ITP. Therefore, this pathway may be a key regulator of the timing of evening activity offset termination, orchestrating its effects in collaboration with the neuropeptide, ITP.

Invasive features of superficial oesophageal squamous cell carcinoma-analysis of risk factors for lymph node metastasis.

There are currently no studies that have examined the clinicopathological factors in detail, including the histological images of the invasive front, and the risk of lymph node metastasis (LNM) in superficial oesophageal squamous cell carcinoma (SESCC). This study aimed to develop an algorithm that contributes to a better assessment of the risk of LNM and recurrence in SESCC. Clinicopathological factors, such as submucosal (SM) invasion distance, were examined in 88 surgically resected cases of SESCC. An SM invasion distance of 600 µm was the statistically best customer value for LNM (p = 0.0043). To obtain a histological image of the invasive front, we evaluated modified tumour budding (MBD) by modifying the number of tumour foci constituent cells and foci in tumour budding. We also evaluated the smallest number of tumour foci. Using these factors, we developed an algorithm to predict the risk of LNM. The best algorithm was created using an SM invasion distance of 600 µm and an index of 5 or more foci consisting of five or fewer tumour cells in the MBD (MBD5 high-grade ≥ 5), which was also significantly associated with recurrence-free survival (p = 0.0305). Further study of the algorithm presented in this study is expected to improve the quality of life of patients by selecting appropriate additional treatments after endoscopic resection and appropriate initial treatment for SESCC.