Biology subjects

Uemura, R.

Publications and source records attributed to Uemura, R..

3 recordsLinked to original sources

bioRxiv2026

Enterococcus faecalis is involved in the progression of the early stages of latent chronic pancreatitis surrounding pancreatic cancer tissue

(Objective) In our previous research, we identified latent chronic pancreatitis in the normal tissue surrounding pancreatic cancer. We also discovered the presence of Enterococcus faecalis (E. faecalis), a type of intestinal bacterium, in the pancreatic fluid and tissue of pancreatic cancer patients, suggesting it may be one of the factors contributing to the development of latent chronic pancreatitis. In this study, we performed pathological analyses to investigate its characteristics and investigate a possibility of E. faecalis infection. (Methods) Pathological analyses were performed, using 16 cases of pancreatic cancer and intraductal papillary mucinous neoplasia (IPMN) involving lesions in the pancreas tail. The involvement of E. faecalis was investigated with immunohistochemical analysis and serological methods. (Results) All cases exhibited inflammatory changes in pancreatic tissue without a clinical diagnosis of chronic pancreatitis, along with macrophage infiltration. These changes did not significantly differ according to preoperative treatment. DNA encoding E. faecalis 16s ribosomal RNA was detected in many cases, however, a positive immunostaining to E. faecalis was observed in only a few cases. Serum capsular polysaccharide (CPS) antibody levels exceeding the mean values were observed in patients with established chronic pancreatitis, while the level was not correlated with E. faecalis immunostaining. (Conclusion) These results suggest the E. faecalis infection is involved in the early stage of the progression of chronic latent pancreatitis and the diagnostic technology incorporating novel multi-biomarkers may be useful for identifying high-risk individuals for future pancreatic cancer development.

cancer biology↗

bioRxiv2024

Development of a simple and highly sensitive method for the concentration and detection of African swine fever virus in oral fluids and its feasibility assessment on raised pigs in Northern Vietnam

BackgroundEarly detection and early slaughter through quarantine are essential to prevent the spread of the African swine fever virus (ASFV). Highly accurate testing is effective for early detection, but it is still difficult to establish a system, especially in the Global South. Pooled oral fluids tests have been used for simple pathogen monitoring, but compared to blood tests, the virus concentration in oral fluids is low, resulting in false negative and missing true positive cases. We collected oral fluids from raised pigs in northern Vietnam and attempted a highly sensitive ASFV survey using a newly developed virus concentration and detection method. ResultsIn a spike test, the developed method showed up to 100 times greater sensitivity than a reference method. To compare and evaluate the performance of the developed method, a total of 68 pooled oral fluid samples were collected, 63 from northern Vietnam and 5 from southern Japan. Using real-time PCR, 9/68 (13.2%) were positive by the reference method, and 23/68 (33.8%) by the developed method. Using real-time LAMP, 1/68 (1.5%) were positive by the reference method and 6/68 (8.8%) by the developed method. ConclusionsThe developed method improved the sensitivity of ASFV detection from oral fluids and enabled early diagnosis of pigs before the onset of the disease. The developed method has the potential to enable simple and highly sensitive diagnosis of ASF, which is essential for its early diagnosis and effective surveillance. HighlightO_LIA method has been developed to detect ASFV in pig oral fluids with up to 100 times greater sensitivity than a reference method. C_LIO_LIThe developed method combines innovative pretreatment in less than 60 min with conventional nucleic acid extraction with a column kit followed by real-time PCR or LAMP. C_LIO_LIApplied to feasibility assessment for ASF diagnosis on raised pigs, the developed method showed higher diagnostic sensitivity than the reference method. C_LIO_LIThe developed method can be a useful tool that contributes to early detection and surveillance of ASFV. C_LI

microbiology↗

bioRxiv2018

Changes in clock gene expression in esophagus in rat reflux esophagitis

Background and AimsGastroesophageal reflux disease (GERD) is strongly associated with sleep disturbances. Clock genes harmonize circadian rhythms by their periodic expression and regulate several physiological functions. However, the association between clock genes and GERD is still unknown. We investigated whether reflux esophagitis affects circadian variability of clock genes in the esophagus and other organs using a rat reflux esophagitis model.\n\nMethodsReflux esophagitis was induced in 7-week-old male Wistar rats. Sham-operated rats were used as controls. Rats were sacrificed at 09:00 (light period) and 21:00 (dark period) 3 days (acute phase) and 21 days (chronic phase) after induction of esophagitis. The expression levels of clock gene mRNAs such as Per1, Per2, Per3, Cryl, Cry2, Arntl, and Clock in the esophagus were investigated by qPCR. Arntl expression was examined in stomach, small intestine, colon, and liver tissues. Serum melatonin and IL-6 levels were measured by ELISA.\n\nResultsHistological examination of reflux esophagitis mainly revealed epithelial defects with marked inflammatory cell infiltration in the acute phase, and mucosal thickening with basal cell hyperplasia in the chronic phase. Circadian variability of clock genes, except Cry1, was present in the normal esophagus, and was completely disrupted in reflux esophagitis during the acute phase. The circadian variability of Per2, Per3, and Arntl returned to normal, but disruption of Per1, Cry2, and Clock was present in the chronic phase. Disruption of circadian variability of Arntl was observed in the esophagus, as well as in the stomach, small intestine, and liver tissues in reflux esophagitis during the acute phase. There were no significant differences in serum melatonin and IL-6 levels between control and reflux esophagitis animals in both acute and chronic phases.\n\nConclusionDisruption to circadian variability of clock genes may play a role in the pathogenesis of GERD.

pathology↗