Shimane University

Recent reports have suggested the widespread distribution of a novel form of plastic waste on marine shorelines; plastics seemingly originating from the burning and melting of plastic waste. These plastics, termed pyroplastics, were collected in the intertidal zone of beaches on the Sea of Japan coastline and analyzed for their composition. Despite their unknown origins, these pyroplastics are a ubiquitous presence along the Sea of Japan coast. A total of 146 pyroplastics were found with the highest occurring at Koura, the enclosed bay site, with 2.1 pyroplastics/m² and the lowest at Chirihama, the site furthest north, with 0.3 pyroplastics/m². Among these were mixtures of plastic polymer types, which included the most commonly used plastics: polyethylene, polypropylene and polystyrene. Most samples did not show signs of colonization by marine organisms, suggesting a greater likelihood of being produced and transported locally. Still, there are various aspects to these novel plastic types that are unknown, specifically with respect to their toxicity and their propensity to fragment into microplastics.

The incidence of Helicobacter pylori (Hp)-naïve gastric neoplasms (HpNGNs) is increasing due to a growing Hp-naïve population and improved recognition. Among these, HpNGNs that predominantly exhibit foveolar-cell differentiation include foveolar-type gastric adenomas (FGA) and fundic gland polyps with dysplasia (FGPD). Traditionally, FGAs have been considered large, whitish, flat lesions (flat-type FGA), primarily associated with syndromic conditions, such as familial adenomatous polyposis (FAP) and gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS), while sporadic cases are rare. This type exhibits a gastric immunophenotype with diverse differentiation, mainly toward foveolar cells, and harbors APC and KRAS mutations in all sporadic and most syndromic cases. A distinct subset of FGAs, termed foveolar-type gastric adenoma with a raspberry-like appearance (FGA-RA), has been identified. It presents as small, reddish polyps with unique macroscopic and microscopic features and only occurs sporadically. FGA-RA often mimics gastric hyperplastic polyps macroscopically and typically exhibits low-grade dysplasia, making biopsy-based diagnosis challenging and leading to its historical underrecognition. It shows pure foveolar differentiation and consistently harbors Krüppel-like factor 4 (KLF4) mutations. FGPD primarily develops sporadically in Hp-naïve individuals with long-term proton pump inhibitor use. A syndromic form, resembling flat-type FGAs, is also associated with FAP and GAPPS. Histologically, FGPD features dysplasia confined to the superficial foveolar epithelium and mucus neck cells overlying fundic gland polyps, with APC mutations detected in approximately 50% of cases. This review explores the clinicopathological and molecular characteristics of HpNGNs with predominant foveolar cell differentiation, emphasizing the need for an updated histological diagnostic framework.

Coastal marine ecosystems face complex pressures from both anthropogenic activities and climate variability. However, due to the recent overwhelming signals of human-induced impacts, there is a paucity of evidence of paleoecological archives on the combined effects of anthropogenic and climatic impacts on coastal marine ecosystem. By analyzing ostracod(s) as an indicator of paleo benthic ecosystem at a unique, less urbanized marine site in Hong Kong, we discovered that moderate signal (i.e., not overly strong, like total defaunation) of gradual ostracod community shifts in response to mild human-induced stresses, and it gave us a chance to observe how the ecosystem change gradually in response to different types of human and climatic stressors. We found that pollutants shifted marine community from 1960s, aligning with Hong Kong's industrial development history. Local ecosystem has been affected by eutrophication gradually, starting rather late with major negative impacts from 1980s. We also found evidence of strong monsoons between ~1940s-1960s which aided the establishment of tropical species. Our integrated investigation on paleoecology, environmental human stresses (eutrophication, hypoxia, and pollution), climate change, and socioeconomics in the past century reveals complicated change of coastal marine ecosystem under various influences and provides a critical baseline for better optimized management and conservation in this rapidly developing subtropical region.