Essential updates 2020/2021 : Current topics of simulation and navigation in hepatectomy

With the development of three-dimensional (3D) simulation software, preoperative simulation technology is almost completely established. The remaining issue is how to recognize anatomy three-dimensionally. Extended reality is a newly developed technology with several merits for surgical application: no requirement for a sterilized display monitor, better spatial awareness, and the ability to share 3D images among all surgeons. Various technology or devices for intraoperative navigation have also been developed to support the safety and certainty of liver surgery. Consensus recommendations regarding indocyanine green fluorescence were determined in 2021. Extended reality has also been applied to intraoperative navigation, and artificial intelligence (AI) is one of the topics of real-time navigation. AI might overcome the problem of liver deformity with automatic registration. Including the issues described above, this article focuses on recent advances in simulation and navigation in liver surgery from 2020 to 2021

肝胆膵手術の画像支援

We introduced the pre and intra-operative３D hologram support system, which was a computer graphics model, with extended reality（XR）techniques. It contributed to a more extensive view of ３D anatomy from various angles and the sharing of the same hologram from several respective operators’ angles. The colabolation between such an operative supporrt and pathological diagnosis enables more safe and higher quality operations

Regeneration of caudate lobe in left lobe graft

Background : The aim of this study is to clarify the regeneration of the CL (caudate lobe) without any reconstructions of short hepatic veins (SHVr) after LDLT (living donor liver transplantation) and compare the regeneration of the CL after right hepatectomy (Rt. Hx), as the surrogate model of extended left lobe graft (Ex LLG) with complete SHVr. Methods : Eleven Ex LLGs with CL were included in this study. SHVr was not performed in all cases. The volumetry was performed before, one month and six months after LDLT. Seven patients who underwent Rt. Hx were also included in this study as the surrogate model. Results : In Ex LLGs with CL, the regeneration rate of the large CL (> 30 ml) was worse than that of small CL (< 30 ml). In the surrogate model, the regeneration rate of the CL was not worse than other segments. However, the regeneration rate of the large CL was also worse than that of small CL even in the presence of complete SHVr. Conclusions : The regeneration of the large CL was worse than that of the small CL regardless of the presence or absence of SHVr, indicating that SHVr in Ex LLG with CL might not be necessary

脂肪由来間葉系幹細胞からインスリン産生細胞への分化誘導に際しての皮下および腹腔内脂肪の特性の差異に関する研究

The aim of this study was to investigate the characteristics of insulin producing cells (IPCs) differentiated from adipose-tissue derived stem cells (ADSCs) isolated from human subcutaneous and visceral adipose tissues and identify ADSCs suitable for differentiation into efficient and functional IPCs. Subcutaneous and visceral adipose tissues collected from four (4) patients who underwent digestive surgeries at The Tokushima University (000035546) were included in this study. The insulin secretion of the generated IPCs was investigated using surface markers by: fluorescence activated cell sorting (FACS) analysis; cytokine release; proliferation ability of ADSCs; in vitro (glucose-stimulated insulin secretion: (GSIS) test/in vivo (transplantation into streptozotocin-induced diabetic nude mice). The less fat-related inflammatory cytokines secretions were observed (P < 0.05), and the proliferation ability was higher in the subcutaneous ADSCs (P < 0.05). Insulin expression and GISI were higher in the subcutaneous IPCs (P < 0.01 and P < 0.05, respectively). The hyperglycaemic state of all mice that received IPCs from subcutaneous fat tissue converted into normo-glycaemia in thirty (30) days post-transplantation (4/4,100%). Transplanted IPCs were stained using anti-insulin and anti-human leukocyte antigen antibodies. The IPCs generated from the ADSCs freshly isolated from the human fat tissue had sufficient insulin secreting ability in vitro and in vivo

Nrf2 activation drive macrophages polarization and cancer cell epithelial-mesenchymal transition during interaction

Background: The M2 phenotype of tumor-associated macrophages (TAM) inhibits the anti-tumor inflammation, increases angiogenesis and promotes tumor progression. The transcription factor Nuclear Factor (erythroid-derived 2)-Like 2 (Nrf2) not only modulates the angiogenesis but also plays the anti-inflammatory role through inhibiting pro-inflammatory cytokines expression; however, the role of Nrf2 in the cancer cell and macrophages interaction is not clear. Methods: Hepatocellular carcinoma cells (Hep G2 and Huh 7) and pancreatic cancer cells (SUIT2 and Panc-1) were co-cultured with monocytes cells (THP-1) or peripheral blood monocytes derived macrophages, then the phenotype changes of macrophages and epithelial-mesenchymal transition of cancer cells were detected. Also, the role of Nrf2 in cancer cells and macrophages interaction were investigated. Results: In this study, we found that cancer cells could induce an M2-like macrophage characterized by up-regulation of CD163 and Arg1, and down-regulation of IL-1b and IL-6 through Nrf2 activation. Also, Nrf2 activation of macrophages promoted VEGF expression. The Nrf2 activation of macrophages correlated with the reactive oxygen species induced by cancer cells derived lactate. Cancer cells educated macrophages could activate Nrf2 of the cancer cells, in turn, to increase cancer cells epithelial-mesenchymal transition (EMT) through paracrine VEGF. These findings suggested that Nrf2 played the important role in the cancer cells and macrophages interaction. Conclusions: Macrophage Nrf2 activation by cancer cell-derived lactate skews macrophages polarization towards an M2-like phenotype and educated macrophages activate Nrf2 of the cancer cells to promote EMT of cancer cells. This study provides a new understanding of the role of Nrf2 in the cancer cell and TAM interaction and suggests a potential therapeutic target

Polarization fields in nitride nanostructures: ten points to think about

Macroscopic polarization, both of intrinsic and piezoelectric nature, is unusually strong in III-V nitrides, and the built in electric fields in the layers of nitride-based nanostructures, stemming from polarization changes at heterointerfaces, have a major impact on the properties of single and multiple quantum wells, high mobility transistors, and thin films. The concepts involved in the theory and applications of polarization in nitrides have encountered some resistance in the field. Here we discuss critically ten ``propositions'' aimed at clarifying the main controversial issues.Comment: RevTeX 5 pages, 2 embedded figure

Stomagen positively regulates stomatal density in Arabidopsis.

葉の気孔の数を増加させる因子の発見～CO2削減や食糧増産へ向けて～. 京都大学プレスリリース. 2009-12-10.Stomata in the epidermal tissues of leaves are valves through which passes CO(2), and as such they influence the global carbon cycle. The two-dimensional pattern and density of stomata in the leaf epidermis are genetically and environmentally regulated to optimize gas exchange. Two putative intercellular signalling factors, EPF1 and EPF2, function as negative regulators of stomatal development in Arabidopsis, possibly by interacting with the receptor-like protein TMM. One or more positive intercellular signalling factors are assumed to be involved in stomatal development, but their identities are unknown. Here we show that a novel secretory peptide, which we designate as stomagen, is a positive intercellular signalling factor that is conserved among vascular plants. Stomagen is a 45-amino--rich peptide that is generated from a 102-amino-acid precursor protein designated as STOMAGEN. Both an in planta analysis and a semi-in-vitro analysis with recombinant and chemically synthesized stomagen peptides showed that stomagen has stomata-inducing activity in a dose-dependent manner. A genetic analysis showed that TMM is epistatic to STOMAGEN (At4g12970), suggesting that stomatal development is finely regulated by competitive binding of positive and negative regulators to the same receptor. Notably, STOMAGEN is expressed in inner tissues (the mesophyll) of immature leaves but not in the epidermal tissues where stomata develop. This study provides evidence of a mesophyll-derived positive regulator of stomatal density. Our findings provide a conceptual advancement in understanding stomatal development: inner photosynthetic tissues optimize their function by regulating stomatal density in the epidermis for efficient uptake of CO(2)

亜鉛イオン濃度変化は脂肪由来幹細胞から作成するインスリン産生細胞の成熟を反映する

The generation of insulin-producing cells (IPCs) from pluripotent stem cells could be a breakthrough treatment for type 1 diabetes. However, development of new techniques is needed to exclude immature cells for clinical application. Dithizone staining is used to evaluate IPCs by detecting zinc. We hypothesised that zinc ion (Zn2+) dynamics reflect the IPC maturation status. Human adipose-derived stem cells were differentiated into IPCs by our two-step protocol using two-dimensional (2D) or 3D culture. The stimulation indexes of 2D -and 3D-cultured IPCs on day 21 were 1.21 and 3.64 (P < 0.05), respectively. The 3D-cultured IPCs were stained with dithizone during culture, and its intensity calculated by ImageJ reached the peak on day 17 (P < 0.05). Blood glucose levels of streptozotocin-induced diabetic nude mice were normalised (4/4,100%) after transplantation of 96 3D-cultured IPCs. Zn2+ concentration changes in the medium of 3D cultures had a negative value in the early period and a large positive value in the latter period. This study suggests that Zn2+ dynamics based on our observations and staining of zinc transporters have critical roles in the differentiation of IPCs, and that their measurement might be useful to evaluate IPC maturation as a non-destructive method

Intraoperative 3D hologram in liver surgery

An intra-operative 3D hologram with mixed reality techniques contributed to “last-minute simulation”, not for “navigation” in liver surgery. This intra-operative hologram might be a new next-generation operation-supportive tool in terms of spatial awareness, sharing, and simplicity.Objective The aim of this study was to investigate the potential of an intra-operative 3D hologram, which was a computer graphics (CG) model liver, with mixed reality (MR) techniques in liver surgery. Summary Background Data The merits for the application of a hologram for surgical support are: 1) no sterilized display monitor; 2) better spatial awareness; and 3) 3D images shared by all the surgeons. Methods 3D polygon data using pre-operative computed tomography (CT) data was installed into head mount displays, HoloLens (Microsoft Corporation, Redmond, WA). Results In a Wi-Fi-enabled operative room, several surgeons wearing HoloLens succeeded in sharing the same hologram and moving that hologram from respective operators’ angles by means of easy gesture-handling without any monitors. The intra-operative hologram contributed to better imagination of tumor locations, and for determining the parenchymal dissection line in the hepatectomy for the patients with more than twenty (20) multiple colo-rectal liver metastases (CRLMs). In another case, the hologram enabled a safe Gliisonean pedicle approach for hepato-cellular carcinoma (HCC) with a hilar anatomical anomaly. Surgeons could easily compare the real patient’s anatomy and that of the hologram just before the hepatic hilar procedure. Conclusions This initial experience suggested that an intra-operative hologram with MR techniques contributed to “last-minute simulation”, not for “navigation”. The intra-operative hologram might be a new next-generation operation-supportive tool in terms of spatial awareness, sharing, and simplicity