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Background Hemostasis is very important for a safe surgery, particularly in endoscopic surgery. Accordingly, in the last decade, vessel-sealing systems became popular as hemostatic devices. However, their use is limited due to thermal damage to organs, such as intestines and nerves. We developed a new method for safe coagulation using a vessel-sealing system, termed flat coagulation (FC). This study aimed to evaluate the efficacy of this new FC method compared to conventional coagulation methods. Methods We evaluated the thermal damage caused by various energy devices, such as the vessel-sealing system (FC method using LigaSure™), ultrasonic scissors (Sonicision™), and monopolar electrosurgery (cut/coagulation/spray/soft coagulation (SC) mode), on porcine organs, including the small intestine and liver. Furthermore, we compared the hemostasis time between the FC method and conventional methods in the superficial bleeding model using porcine mesentery. Results FC caused less thermal damage than monopolar electrosurgery’s SC mode in the porcine liver and small intestine (liver: mean depth of thermal damage, 1.91 ± 0.35 vs 3.37 ± 0.28 mm; p = 0.0015). In the superficial bleeding model, the hemostasis time of FC was significantly shorter than that of electrosurgery’s SC mode (mean, 19.54 ± 22.51 s vs 44.99 ± 21.18 s; p = 0.0046). Conclusion This study showed that the FC method caused less thermal damage to porcine small intestine and liver than conventional methods. This FC method could provide easier and faster coagulation of superficial bleeds compared to that achieved by electrosurgery’s SC mode. Therefore, this study motivates for the use of this new method to achieve hemostasis with various types of bleeds involving internal organs during endoscopic surgeries.

Calcium-ion batteries (CIBs) have been attracting attention as next-generation secondary batteries. On the other hand, there are many problems to be studied such as the choice of electrolytes and electrode materials. In this study, we investigate the influence of the presence of water in electrolyte on the Ca2+ insertion/extraction properties of α-V2O5. Electrochemical tests showed that the overvoltage gradually decreases as the amount of water increases. Structural and elemental analyses suggested co-insertion of H+ in the water containing electrolyte and although the co-insertion amount of H+ differs depending on the amount of water, there is not much change in overvoltage reduction. So, the influence of H+ co-insertion on electrochemical properties is considered to be small. Bulk structure analysis of the electrolyte suggested that hydration to Ca2+ and dissociation of the contact ion pair of Ca2+ and anion progressed with increasing the amount of water in the electrolyte. From the above, it was revealed that the presence of water in electrolyte caused a large change in its structure, which has an important effect such as a reduction of overvoltage on electrochemical properties.

Objectives. In recent years, video-assisted thoracoscopic surgery (VATS) has increasingly become the preferred technique for thoracic surgery. However, the inherent characteristics of the lungs as large, soft, slippery, and delicate creates difficulties for pulmonary surgery. In this article, we outline the development and assessment of a balloon-based organ retractor for VATS via collaboration between medical and engineering personnel. Methods. A dry lab trial and accompanying questionnaire assessment were performed by a group of thoracic surgeons. Objective pressure measurements were obtained, and animal experiment on pigs was performed. Results. In the dry lab trial, use of the developed organ retractor required significantly less time and resulted in fewer difficulties than using a Cherry Dissector. The measured pressure per mm2 of the developed retractor was clearly lower than that for the Cherry Dissector. The questionnaire completed by the surgeons following the dry lab and animal experiments showed that most of the surgeons (7 surgeons out of 9) were satisfied with the quality of the balloon-based retractor based on a score of 3.13 ± 0.28 (mean ± standard deviation) out of 4.0. During the animal experiment, the balloon-based retractor provided stable and clear viewing with minimal need for adjustment. Conclusion. This balloon-based retractor could contribute to increased safety and less-invasive VATS.

Superior thermal performance of GaN/graphite composite (GC) bonded substrate having an ultralow thermal resistance (Rth) has been demonstrated. Thermal transition in GaN-on-GC features fast relaxation process in GaN and slow case in GC, respectively. The temperature plateau at the GaN/GC interface indicates the Rth across this interface is quite small and hence can be ignored. High-quality bonding interface and homogenous layer properties were obtained for the GaN-on-GC system. This favors the acoustic phonon transport and is bound to well contribute to the outstanding thermal performance. The GaN/GC bonded substrate provides a promising candidate for thermal management applications in GaN-based electronics.

Bioengineered lungs consisting of a decellularized lung scaffold that is repopulated with a patient’s own cells could provide desperately needed donor organs in the future. This approach has been tested in rats, and has been partially explored in porcine and human lungs. However, existing bioengineered lungs are fragile, in part because of their immature vascular structure. Herein, we report the application of adipose-derived stem/stromal cells (ASCs) for engineering the pulmonary vasculature in a decellularized rat lung scaffold. We found that pre-seeded ASCs differentiated into pericytes and stabilized the endothelial cell (EC) monolayer in nascent pulmonary vessels, thereby contributing to EC survival in the regenerated lungs. The ASC-mediated stabilization of the ECs clearly reduced vascular permeability and suppressed alveolar hemorrhage in an orthotopic transplant model for up to 3?h after extubation. Fibroblast growth factor 9, a mesenchyme-targeting growth factor, enhanced ASC differentiation into pericytes but overstimulated their proliferation, causing a partial obstruction of the vasculature in the regenerated lung. ASCs may therefore provide a promising cell source for vascular regeneration in bioengineered lungs, though additional work is needed to optimize the growth factor or hormone milieu for organ culture., Scientific Reports, 7, 8447; 2017

Azygos vein aneurysm is a rare disease. Surgical resection is usually performed when it ruptures. To avoid the thromboembolism, procedures that do not touch or push the aneurysm are recommended. Herein, we report a case of idiopathic azygos vein aneurysm. A 56-year-old woman was admitted to the hospital for right lateral chest pain. Chest enhanced multi-detector CT revealed an azygos vein aneurysm in the posterior mediastinal space. No thrombus in the aneurysm was detected before surgery. Video-assisted thoracic surgery was performed to treat the aneurysm. The patient was discharged from the hospital 4 days after surgery. Video-assisted thoracic surgery was a good option to treat an azygos vein aneurysm, and an enhanced multi-detector CT was useful for performing surgery safely.

Recent advances in tissue engineering using decellularized organ scaffolds have expanded the possibilities for organ replacement therapy. However, detergent-based decellularization itself damages the extracellular matrix (ECM), which results in failure associated with the transplanted bioengineered organ. This study determined that potassium laurate (PL), a natural detergent, significantly reduces lung ECM damage during the decellularization process compared with protocols using sodium dodecyl sulfate. PL-decellularized lungs showed better microarchitecture preservation and low biological reactions after subcutaneous implantation. PL-decellularized scaffolds supported rat lung endothelial cell attachment/proliferation and the bioengineered lungs significantly reduced lung congestion after transplantation.

Biomaterials have been used for a long time in the field of medicine. Since the success of "tissue engineering" pioneered by Langer and Vacanti in 1993, tissue engineering studies have advanced from simple tissue generation to whole organ generation with three-dimensional reconstruction. Decellularized scaffolds have been widely used in the field of reconstructive surgery because the tissues used to generate decellularized scaffolds can be easily harvested from animals or humans. When a patient's own cells can be seeded onto decellularized biomaterials, theoretically this will create immunocompatible organs generated from allo- or xeno-organs. The most important aspect of lung tissue engineering is that the delicate three-dimensional structure of the organ is maintained during the tissue engineering process. Therefore, organ decellularization has special advantages for lung tissue engineering where it is essential to maintain the extremely thin basement membrane in the alveoli. Since 2010, there have been many methodological developments in the decellularization and recellularization of lung scaffolds, which includes improvements in the decellularization protocols and the selection and preparation of seeding cells. However, early transplanted engineered lungs terminated in organ failure in a short period. Immature vasculature reconstruction is considered to be the main cause of engineered organ failure. Immature vasculature causes thrombus formation in the engineered lung. Successful reconstruction of a mature vasculature network would be a major breakthrough in achieving success in lung engineering. In order to regenerate the mature vasculature network, we need to remodel the vascular niche, especially the microvasculature, in the organ scaffold. This review highlights the reconstruction of the vascular niche in a decellularized lung scaffold. Because the vascular niche consists of endothelial cells (ECs), pericytes, extracellular matrix (ECM), and the epithelial-endothelial interface, all of which might affect the vascular tight junction (TJ), we discuss ECM composition and reconstruction, the contribution of ECs and perivascular cells, the air-blood barrier (ABB) function, and the effects of physiological factors during the lung microvasculature repair and engineering process. The goal of the present review is to confirm the possibility of success in lung microvascular engineering in whole organ engineering and explore the future direction of the current methodology.

Introduction: Extracutaneous glomus tumors occurring in the bronchus is very rare. Complete resection is basic procedure for treatment of glomus tumor. We present a glomus tumor of the left main bronchus that was successfully treated with rigid bronchoscopy followed by sleeve resection of the left main bronchus. Presentation of case: A 56-year-old man underwent two term resections to glomus tumor that originated from the left main bronchus. Firstly, we performed palliative resection with rigid bronchoscopy to make the correct diagnosis and evaluate the extent of the tumor. We subsequently performed curative resection. No complications or recurrence has occurred since the operation took place one year ago. Discussion: Before curative resection, it is important to confirm the diagnosis and spread of the tumor. Therefore, palliative tumor resection by rigid bronchoscopy was useful to make the correct diagnosis, evaluate the extent of the tumor and open the bronchial lumen. After bronchoscopic treatment, curative pulmonary resection was performed and preservation of lung function was successful. Conclusion: Two term resections enabled us to make an accurate diagnosis and evaluation, thereby preserving respiratory function without pulmonary resection., International Journal of Surgery Case Reports, 41, pp.191-193; 2017

Lung transplantation is the last option for the treatment of end stage chronic lung disorders. Because the shortage of donor lung organs represents the main hurdle, lung regeneration has been considered to overcome this hurdle. Recellularization of decellularized organ scaffold is a promising option for organ regeneration. Although detergents are ordinarily used for decellularization, other approaches are possible. Here we used high alkaline (pH12) sodium hydroxide (NaOH)-PBS solution without detergents for lung decellularization and compared the efficacy on DNA elimination and ECM preservation with detergent based decellularization solutions CHAPS and SDS. Immunohistochemical image analysis showed that cell components were removed by NaOH solution as well as other detergents. A Collagen and GAG assay showed that the collagen reduction of the NaOH group was comparable to that of the CHAPS and SDS groups. However, DNA reduction was more significant in the NaOH group than in other groups (p < 0.0001). The recellularization of HUVEC revealed cell attachment was not inferior to that of the SDS group. Ex vivo functional analysis showed 100% oxygen ventilation increased oxygen partial pressure as artificial hemoglobin vesicle-PBS solution passed through regenerated lungs in the SDS or NaOH group. It was concluded that the NaOH-PBS based decellularization solution was comparable to ordinal decellularizaton solutions and competitive in cost effectiveness and residues in the decellularized scaffold negligible, thus providing another potential option to detergent for future clinical usage.

Prefoldin is a hexameric molecular chaperone found in the cytosol of archaea and eukaryotes. Its hexameric complex is built from two related classes of subunits, and has the appearance of a jellyfish: Its body consists of a double β-barrel assembly with six long tentacle-like coiled coils protruding from it. Using the tentacles, prefoldin captures an unfolded protein substrate and transfers it to a group II chaperonin. Based on structural information from archaeal prefoldins, mechanisms of substrate recognition and prefoldin-chaperonin cooperation have been investigated. In contrast, the structure and mechanisms of eukaryotic prefoldins remain unknown. In this study, we succeeded in obtaining recombinant prefoldin from a thermophilic fungus, Chaetomium thermophilum (CtPFD). The recombinant CtPFD could not protect citrate synthase from thermal aggregation. However, CtPFD formed a complex with actin from chicken muscle and tubulin from porcine brain, suggesting substrate specificity. We succeeded in observing the complex formation of CtPFD and the group II chaperonin of C. thermophilum (CtCCT) by atomic force microscopy and electron microscopy. These interaction kinetics were analyzed by surface plasmon resonance using Biacore. Finally, we have shown the transfer of actin from CtPFD to CtCCT. The study of the folding pathway formed by CtPFD and CtCCT should provide important information on mechanisms of the eukaryotic prefoldin–chaperonin system., This research was supported by grants-in-aids for scientific research (JP18H04690, JP16H04572, JP16H00753 and JP15J08261) from the Ministry of Education, Science, Sports, and Culture of Japan, the Joint Studies Program (2017-2018) in the Okazaki BIO-NEXT project of National Institutes of Natural Sciences and a grant from CREST (JPMJCR13M1), the program of the Joint Usage/Research Center for Developmental Medicine (IMEG, Kumamoto University). This work was also supported by the grant BFU2016-75984 (AEI/FEDER, UE).

Recently, calcium ion batteries (CIBs) have been attracting attention as next-generation batteries because of their higher energy density, higher safety, lower costs and more abundant elements than lithium ion batteries (LIBs). On the other hand, CIBs have several problems impeding their progress. One critical issue is the development of a suitable organic electrolyte without a negative impact on the electrochemical properties of the electrode material. In our past study, we reported that the overvoltage decreased when water was added to the electrolyte1. One reason for the decrease of overvoltage is a change in the electrolyte structure such as the solvation structure and the degree of salt dissociation. In this study, we investigated the electrolyte structure with varied organic solvent species and salt concentration, and examined the electrolyte dependency on Ca2+ insertion and extraction properties of V2O5. We used Ca(TFSI)2 as the electrolyte salt, which was vacuum dried at 150℃ for 12h before use. For the organic solvents, EC: DMC (1:1 in vol.), EC: PC (1:1 in vol.), triglyme (G3) and acetonitrile (AN) were used. The concentration of electrolyte was adjusted to 0.2-0.5 molL-1.V2O5 nano-sheet synthesized by hydrothermal-assisted method2 was used as the working electrode. The electrode was prepared by mixing the synthesized V2O5, acetylene black and polyvinylidene difluoride dissolved in N-methyl-2pyrrolidinone with a weight ratio of 70:20:10, then coated onto a carbon coated titanium foil and vacuum dried at 120℃ overnight. A constant current discharge-charge experiment was performed at 0.05C-1C. The results of electrolyte structure analysis showed that the contact ion pair (CIP) decreased as the dipole moment of the organic solvent decreased except for G3. When G3 was used, it is considered that the solvent-separated ion pair (SSIP) was formed because of the small dipole moment of G3. Interestingly, a decrease in the amount of CIP due to the decrease of concentration was observed when using EC: DMC or EC: PC, but not when using G3 or AN. The results of the constant current discharge-charge experiment were strongly related to the amount of CIP. The coulombic efficiency tended to improve as the amount of CIP decreased except for using G3, in particular, a high coulombic efficiency of 95% was shown when using 0.3M Ca(TFSI)2/EC: DMC. As a factor of the instability of electrolyte when G3 was used, Ca2+(G3)TFSI- SSIP may also be reductively unstable as Ca2+TFSI- CIP. On the other hand, G3-based electrolyte showed the lowest overvoltage and the best rate performance. According to the surface analysis of the electrode after the test, the concentration of calcium in the surface film was less than that for other solvents. It suggests that the nature of the surface film may be related to a decrease in the overvoltage. When a solvent other than G3 was used, the overvoltage decreased as the amount of CIP decreased, and a relatively high rate performance was obtained for 0.3 molL-1 Ca(TFSI)2/EC: DMC, similar to the tendency of coulombic efficiency. Reference s : [1] Y. Murata et al., Electrochim. Acta 294 (2019) 210-216. [2] H. Song et al., J. Power Sources 294 (2015) 1-7.

The aim of this retrospective study was to evaluate inflammation-based scoring as a prognostic factor for operable non-small-cell lung cancer (NSCLC) in elderly patients. We collected preoperative data from 108 patients aged above 80 years with NSCLC. Inflammation-based scoring systems, including the C-reactive protein to albumin ratio (CAR) and the Glasgow prognostic score (GPS), as well as other clinicopathological factors, were evaluated as potential prognostic factors. The median patient age was 82 (range 80–93) years and the 5-year overall and disease-specific survival rates were 49.7 and 73.9%, respectively. The cut-off value for CAR was calculated using a receiver operator characteristics analysis and patients were dichotomized accordingly. Patients with a low CAR had significantly higher overall survival than those with a high CAR (

Unexpected intraoperative bleeding during thoracoscopic surgery, necessitating emergency conversion to thoracotomy, is gradually being reported. We reviewed our experience of encountering unexpected bleeding during thoracoscopic surgery. We defined “unexpected intraoperative bleeding” as the need for hemostatic procedures with angiorrhaphy, with or without a sealant. The location, cause, and management of injured vessels, and perioperative outcomes were investigated and compared with those for patients without injured vessels. Between 2007 and 2014, a total of 241 thoracoscopic anatomical pulmonary resections were performed at our hospital. Twenty (8.3 %) of these patients required hemostatic procedures with angiorrhaphy, with or without a sealant. The main injured vessels were the pulmonary artery (n = 13) and vein (n = 3) and the main causes of injury were related to technical issues with energy devices and staplers. There were no morbidities related to intraoperative bleeding. The operation time and blood loss were significantly greater in the patients with vessel injury than in those without vessel injury, but perioperative morbidities and the duration of chest tube insertion (4.5 vs. 3.5 days, average, p = 0.20) and postoperative hospital stay (12.7 vs. 11.0 days, average, p = 0.08) were not significantly different. The frequency of unexpected bleeding was relatively high in this series, but its management and outcomes were satisfactory in terms of safety.