Search

Abstract Background Liver disease imposes a significant medical burden that persists due to a shortage of liver donors and an incomplete understanding of liver disease progression. Hepatobiliary organoids (HBOs) could provide an in vitro mini-organ model to increase the understanding of the liver and may benefit the development of regenerative medicine. Methods In this study, we aimed to establish HBOs with bile duct (BD) structures and mature hepatocytes (MHs) using human chemically induced liver progenitor cells (hCLiPs). hCLiPs were induced in mature cryo-hepatocytes using a small-molecule cocktail of TGF-β inhibitor (A-83-01, A), GSK3 inhibitor (CHIR99021, C), and 10% FBS (FAC). HBOs were then formed by seeding hCLiPs into ultralow attachment plates and culturing them with a combination of small molecules of Rock-inhibitor (Y-27632) and AC (YAC). Results These HBOs exhibited bile canaliculi of MHs connected to BD structures, mimicking bile secretion and transportation functions of the liver. The organoids showed gene expression patterns consistent with both MHs and BD structures, and functional assays confirmed their ability to transport the bile analogs of rhodamine-123 and CLF. Functional patient-specific HBOs were also successfully created from hCLiPs sourced from cirrhotic liver tissues. Conclusions This study demonstrated the potential of human HBOs as an efficient model for studying hepatobiliary diseases, drug discovery, and personalized medicine.

Abstract Recently, TNF receptor type 2 (TNFR2) signaling was found to be involved in the proliferation and activation of regulatory T cells (Tregs), a subpopulation of lymphocytes that suppress immune responses. Tregs mediate peripheral immune tolerance, and the disruption of their functions causes autoimmune diseases or allergy. Therefore, cell expanders or regulators of Tregs that control immunosuppressive activity can be used to treat these diseases. We focused on TNFR2, which is preferentially expressed on Tregs, and created tumor necrosis factor-α (TNF-α) muteins that selectively activate TNFR2 signaling in mice and humans, termed R2agoTNF and R2-7, respectively. In this study, we attempted to optimize the structure of muteins to enhance their TNFR2 agonistic activity and stability in vivo by IgG-Fc fusion following single-chain homo-trimerization. The fusion protein, scR2agoTNF-Fc, enhanced the expansion of CD4+CD25+ Tregs and CD4+Foxp3+ Tregs and contributed to their immunosuppressive activity ex vivo and in vivo in mice. The prophylactic administration of scR2agoTNF-Fc suppressed inflammation in contact hypersensitivity and arthritis mouse models. Furthermore, scR2-7-Fc preferentially expanded Tregs in human peripheral blood mononuclear cells via TNFR2. These TNFR2 agonist-Fc fusion proteins, which have bivalent structures, are novel Treg expanders.

Background Can Background be changed from bold to normal text?: Chemically-induced liver progenitors (CLiPs) have promising applications in liver regenerative medicine. We aimed to clarify the efficacy of CLiPs for ameliorating fibrosis in a diet-induced nonalcoholic steatohepatitis rat model, since nonalcoholic fatty liver disease is currently recognized as the most common form of chronic liver disease in developed countries. Methods: Primary mature hepatocytes were isolated from 7-week-old male Wistar rats. To establish CLiPs, isolated hepatocytes were cultured in differentiation medium composed of Y-27632, A-83-01, and CHIR99021 (YAC medium). As an animal model that reproduces NASH pathophysiology, 6-week-old severe combined immunodeficient (SCID) mice were carefully selected and prepared and fed with choline-deficient, L-amino acid-defined, high-fat diet (HFD). After 12 weeks’ HFD feeding, the mice were assigned to continue HFD with or without the administration of rat CLiPs (HFD + CLiPs and HFD-CLiPs, respectively). Rat CLiPs were administered from the spleen. Hepatic fibrosis was semi-quantitatively evaluated according to histology. Liver parenchyma and blood samples were collected for biochemical analyses. Results: Rat CLiPs were positive for CK19 and EpCAM were successfully delivered to the liver. At 8 weeks after CLiPs transplantation, the HFD + CLiPs group showed significantly less positive staining than the HFD-CLiPs group. Alanine aminotransferase significantly improved in the HFD + CLiPs group, as demonstrated by Azan staining and αSMA immunostaining. RT qPCR showed that the liver expression of MMP2 and 9 tended to be higher in the HFD + CLiPs group. Conclusions: The anti-fibrotic effect of CLiPs was demonstrated in the immunodeficient NASH animal model and may have therapeutic applications in humans.

Background: The intrahepatic bile ducts (BDs) play an important role in the modification and transport of bile, and the integration between the BD and hepatocytes is the basis of the liver function. However, the lack of a source of cholangiocytes limits in vitro research. The aim of the present study was to establish three-dimensional BDs combined with human mature hepatocytes (hMHs) in vitro using chemically induced human liver progenitor cells (hCLiPs) derived from hMHs.Methods: In this study, we formed functional BDs from hCLiPs using hepatocyte growth factor and extracellular matrix. BDs expressed the typical biliary markers CK-7, GGT1, CFTR and EpCAM and were able to transport the bile-like substance rhodamine 123 into the lumen. The established three-dimensional BDs were cocultured with hMHs. These cells were able to bind to the BDs, and the bile acid analog CLF was transported from the culture medium through the hMHs and accumulated in the lumen of the BDs. The BDs generated from the hCLiPs showed a BD function and a physiological system (e.g., the transport of bile within the liver) when they were connected to the hMHs.Conclusion: We present a novel in vitro three-dimensional BD combined with hMHs for study, drug screening and the therapeutic modulation of the cholangiocyte function.

Based on corporate financial data for almost all companies listed on the Prime Market of the Tokyo Stock Exchange in fiscal year 2021, we gradually refine a model to explain firms’ sales by the number of employees and total assets. Starting from a Cobb–Douglas-type functional form linearized by a log transformation, the assumption of a skew-symmetric distribution in the error structure and the introduction of industry dummies are shown to be useful not only in searching for a good-fitting model, but also in ensuring the accuracy of important parameters such as the labor share. The introduction of industry dummies helps to improve the accuracy of the model as well as to allow for interpretation as sector-wise total factor productivity.

BackgroundDaikenchuto (DKT) has positive therapeutic effects on improving various gastrointestinal disorders. The present study investigated whether or not DKT has a potential therapeutic effect on chemotherapy-induced acute small intestinal mucositis (CIM) in a rat model.MethodsIntraperitoneal injection of 10 mg/kg methotrexate (MTX) every 3 days for a total of 3 doses was used for induction of CIM in a rat model. The MTX and DKT-MTX groups were injected with MTX as above from the first day, and the DKT-MTX and DKT groups were administered 2.7% DKT via the diet at the same time. The rats were euthanized on day 15.ResultsThe DKT-MTX group showed an improvement in the body weight and conditions of gastrointestinal disorders as well as increased levels of diamine oxidase in plasma and in the small intestinal villi. The pathology results showed that small intestinal mucosal injury in the DKT-MTX group was less severe than that in the MTX group. Immunohistochemistry for myeloperoxidase and malondialdehyde and quantitative real-time polymerase chain reaction (RT-qPCR) for TGF-β1 and HIF-1α showed that DKT attenuated peroxidative damage. The crypts in the DKT-MTX group contained more Ki-67-positive cells than MTX group. The zonula occluden-1 and claudin-3 results showed that DKT promoted repair of the mucosal barrier. RT-qPCR for the amino acid transporters EAAT3 and BO+AT also confirmed that DKT promoted mucosal repair and thus promoted nutrient absorption.ConclusionDKT protected against MTX-induced CIM in a rat model by reducing inflammation, stimulating cell proliferation, and stabilizing the mucosal barrier.

Aim: The formation of a secondary liver is expected in ectopic transplants in liver therapy. It is reported that the transplantation of hepatocyte sheets constitutes one of the techniques used to form a secondary liver. Accordingly, we established a subcutaneous transplant for hepatocyte/fibroblast sheets in previous studies. In this development study with hepatocyte/fibroblast sheets, we evaluated the differences in transplantation sites to promote the maturation of transplanted tissue in a liver injury model. Methods: A cocultured hepatocyte sheet of fibroblasts (TIG-118 cells) and human hepatocytes (PXB cells) was prepared on a temperature-responsive culture dish. The prepared cocultured hepatocyte sheet was either transplanted subcutaneously or on the liver surface of a persistent liver injury model (cDNA-uPA/SCID mouse: uPA mouse), and was evaluated by the human albumin concentration in mouse blood. As a control group, hepatocyte cell sheets were used that were transplanted to both areas and compared. Results: Although the cocultured hepatocyte sheet led to functional improvements in the early stages of culture in subcutaneous transplantation, these did not last in the long-term after transplantation. Although coculture effects were not observed in the liver surface transplantation case, long-term functional expressions in mono- and cocultured sheets in the case of liver surface transplantation were exhibited compared with subcutaneous administration. Conclusion: These results suggest that sustained stimulation of liver regenerationvaries depending on the transplant site and is largely involved in the maturation of hepatocyte tissue.

The synaptic mechanisms of how sleep benefits cognitive functions are not well characterised. Here, the authors show that sleep leads to an overall net decrease in spine-surface GluA1-containing AMPA receptors and that this is correlated with changes in performance after sleep.

Aim Tracheal intubation is a vital resuscitation procedure in the pediatric emergency department (ED). Despite its importance, little is known about the current status of emergency airway management in Japan. In this context, we aimed to investigate the airway management characteristics—particularly the location, patient, and provider factors—in the pediatric ED. Methods We conducted a multicenter, prospective study of five pediatric EDs in Japan from October 2018 to June 2020. The study included all children (aged ≤18 years) who underwent intubation at the pre‐ED or ED setting by physicians and those who were transferred from the ED to the operation room (OR) or pediatric intensive care unit (PICU) for intubation. We described the airway management characteristics according to the location, patient, and provider factors. Results Of 231 children, 9 (4%) were transferred to the OR or PICU for airway management. Among the remaining 222 children, 45 were intubated at the pre‐ED setting and 177 were intubated in the ED. The overall first‐attempt success rate was 72%, with the rate varying by location, patient, and provider factors—for example, 68% at the pre‐ED setting, 67% for children

Phishing attacks have been persistent for more than two decades despite mitigation efforts from academia and industry. We believe that users fall victim to attacks not only because of lack of knowledge and awareness, but also because they are not attentive enough to security indicators and visual abnormalities on the webpages they visit. This is also probably why smart device users, who have more limited screen size and device capabilities compared to desktop users, are three times more likely to fall victim to phishing attacks. To assert our claim, we first investigated general phishing awareness among different groups of smartphone users. We then used smart eyeglasses (electro-oculographic) to experimentally measure the mental effort and vigilance exhibited by users while surfing a website and while playing an Android phishing game that we developed. The results showed that knowledge and awareness about phishing do not seem to have a significant impact on security behaviours, as knowledgeable participants exhibited insecure behaviours such as opening email attachments from unfamiliar senders. However, attentiveness was important as even participants with low cybersecurity knowledge could effectively identify attacks if they were reasonably attentive. Based on these results, we asserted that users are more likely to continue falling victim to phishing attacks due to insecure behaviours, unless tools to lessen the identification burden are provided. We thus recommended implementing a lightweight algorithm into a custom Android browser for detecting phishing sites deceptively without a user interaction. We used fake login credentials as validation agents and monitor the destination server HTTP responses to determine the authenticity of a webpage. We also presented initial evaluation results of this algorithm.

Renal hypouricemia is a disease caused by the dysfunction of renal urate transporters. This disease is known to cause exercise-induced acute kidney injury, but its mechanism has not yet been established. To analyze the mechanism by which hypouricemia causes renal failure, we conducted a semi-ischemic forearm exercise stress test to mimic exercise conditions in five healthy subjects, six patients with renal hypouricemia, and one patient with xanthinuria and analyzed the changes in purine metabolites. The results showed that the subjects with renal hypouricemia had significantly lower blood hypoxanthine levels and increased urinary hypoxanthine excretion after exercise than healthy subjects. Oxidative stress markers did not differ between healthy subjects and hypouricemic subjects before and after exercise, and no effect of uric acid as a radical scavenger was observed. As hypoxanthine is a precursor for adenosine triphosphate (ATP) production via the salvage pathway, loss of hypoxanthine after exercise in patients with renal hypouricemia may cause ATP loss in the renal tubules and consequent tissue damage.

The recent advent of endoscopy has enabled the endoscopic submucosal dissection (ESD) of superficial nonampullary duodenal epithelial tumors. However, the substantially thin wall and presence of bile and pancreatic juice make it technically difficult to perform duodenal ESD without perforation, which leads to lethal complications. The present study evaluated the efficacy of autologous myoblast sheet transplantation for the prevention of late perforation after duodenal ESD in a porcine model. Two weeks before ESD, skeletal muscle was surgically excised from the femur of pigs, and myoblasts were isolated and seeded in temperature-responsive culture dishes to prepare sheets. Immediately after ESD, the autologous myoblast sheets were attached to the serosal surface at the ESD site with omentopexy. The pigs were divided into two groups: the autologous myoblast sheet group ( n = 5), where the myoblast cell sheet was attached to the ESD ulcer part from the duodenal serous side, and the Omentum group ( n = 5), where only the omentum was used. The pigs were sacrificed and analyzed macroscopically and histologically on postoperative day 3. The macroscopic examination of the abdominal cavity revealed perforation in the ESD ulcer area and leakage of bile in the Omentum group but no perforation in the Sheet group. A histopathological examination revealed that continuity of the duodenal wall at the ESD site was maintained with dense connective tissue in the Sheet group. In conclusion, autologous myoblast sheets were useful for preventing perforation after duodenal ESD.

Sleep plays important roles in sensory and motor memory consolidation. Sleep oscillations, reflecting neural population activity, involve the reactivation of learning-related neurons and regulate synaptic strength and, thereby affect memory consolidation. Among sleep oscillations, slow waves (0.5–4 Hz) are closely associated with memory consolidation. For example, slow-wave power is regulated in an experience-dependent manner and correlates with acquired memory. Furthermore, manipulating slow waves can enhance or impair memory consolidation. During slow wave sleep, inter-areal interactions between the cortex and hippocampus (HC) have been proposed to consolidate declarative memory; however, interactions for non-declarative (HC-independent) memory remain largely uninvestigated. We recently showed that the directional influence in a slow-wave range through a top-down cortical long-range circuit is involved in the consolidation of non-declarative memory. At the synaptic level, the average cortical synaptic strength is known to be potentiated during wakefulness and depressed during sleep. Moreover, learning causes plasticity in a subset of synapses, allocating memory to them. Sleep may help to differentiate synaptic strength between allocated and non-allocated synapses (i.e., improving the signal-to-noise ratio, which may facilitate memory consolidation). Herein, we offer perspectives on inter-areal interactions and synaptic plasticity for memory consolidation during sleep.

The title compound, C16H16O2S2·C4H8O2, is a cyclophane derivative, which was crystallized from an ethylacetate/methanol solvent system. The metacyclophane moiety exists with the benzene rings in the syn orientation, and with a pseudo chair–chair conformation for the dithia 12-membered ring. Both hydroxy groups are positioned on same side of this ring. In the crystal, the cyclophane and the lattice solvent are linked by O—H...O hydrogen bonds.