Tissue clearing is a technique that allows light to pass through a sample by chemically altering it so that the tissuecan be observed as it is under a light microscope. Its development has advanced remarkably quickly in recentyears. The concept of tissue-clearing technology, the features of several methods that have been created thus far,and microscopic observations are all introduced in this manuscript. The principles and distinctions of transparencytechniques utilizing hydrophilic compounds—created in Japan and for which various reagent kits are available—are specifically described. Finally, examples of studies utilizing transparency treatment on mouse organ and humantongue specimens are shown.

Minimally invasive surgery is increasingly common in the field of digestive surgery. Recently, robot-assistedsurgery has been added as an option for minimally invasive surgery. The number of hospitals that perform robotassisted surgery and console surgeons who can perform such surgeries are increasing, and the number of operations is increasing. In our hospital, robot-assisted rectal surgery was introduced in July 2022, and robot-assistedhepatectomy was introduced in 2023. This paper describes the status and prospects of robot-assisted surgery indigestive surgery.

Background: Lipocalin-2 is involved in various pathological conditions, such as inflammation, acute organdamage, glucose tolerance abnormalities and cancer. Lipocalin-2 is also related to reactive astrocytes in animalmodels of cerebral ischemia and traumatic brain injury (TBI). This study used a rat model of cortical contusioninjury (CCI) to observe serial changes in lipocalin-2 in brain tissue and blood over time and investigated its usefulness as a biomarker after TBI.Materials and Methods: The CCI model used in this study was male Crl:CD (Sprague–Dawley) rats. The experimental groups were divided into mild and severe groups on the basis of compression. This study examined whether the expression of lipocalin-2 significantly increased in brain tissue and blood after cortical contusion in a ratTBI model. Polymerase chain reaction (PCR) was used to quantify the expression of lipocalin-2 in brain tissue,and Western blotting and enzyme-linked immunosorbent assay (ELISA) were used to assess lipocalin-2 expression in brain tissue and blood after injury in rats.Results: PCR revealed lipocalin-2 expression in all the groups. The expression of lipidalin-2 on the side ipsilateral to the TBI site was significantly elevated at 1, 3 and 24 hours after trauma in both the mild and severe groups.Lipocalin-2 in the blood increased significantly at 3, 6 and 24 hours after trauma in the mild group and immediately after and at 1, 3, 6 and 24 hours after trauma in the severe group.Conclusion: These findings suggest that lipocalin-2 may be closely involved in the physiological condition aftersecondary damage due to TBI and may be useful as a biomarker to predict clinical outcomes after injury.

A 54-year-old woman with type I diabetes presented with an abnormal shadow on a chest computed tomography (CT) scan. The chest CT scan revealed solid ground-glass opacity measuring 6 × 6 mm in size in the rightlower lobe. On the basis of these findings, this patient was clinically suspected of having early primary lungadenocarcinoma. The patient underwent surgical resection of the nodule. The histopathological diagnosis of thelesion was solitary pulmonary capillary hemangioma. After the operation, there was no evidence of recurrence.Pulmonary solitary capillary hemangioma is a very rare disease.