Diagnostic Performance of a Novel Ultra-Thin Endoscopy under Narrow-Band Imaging for Superficial Squamous Cell Carcinoma of the Pharynx and Esophagus.

This study aimed to evaluate the diagnostic utility of the ultra-thin endoscope (UTE) for superficial squamous cell carcinoma (SSCC) compared to magnifying endoscopy (ME) under narrow-band imaging. Participants underwent endoscopic examination, and images of pharyngeal and esophageal SCCs, as along with suspicious SSCC lesions, were collected using UTE and ME on the same day. Three image catalogs (UTE, ME-1, and ME-2) were created and reviewed by three expert endoscopists. ME-1 and ME-2 contained the same endoscopic images. The primary endpoint was the intra-observer agreement for diagnosing SCC. Eighty-six lesions (SCC = thirty-nine, non-SCC = forty-seven) in 43 participants were identified. The kappa values for the intra-observer agreement between UTE and ME-1 vs. the control (ME-1 vs. ME-2) were 0.74 vs. 0.84, 0.63 vs. 0.76, and 0.79 vs. 0.88, respectively. The accuracies for diagnosing SCC by UTE and ME-1 were 87.2% vs. 86.0%, 78.0% vs. 73,2%, and 75.6 vs. 82.6%, respectively, with no significant differences (p > 0.05). The rates of lesions that were diagnosed with confidence by UTE and ME-1 were 30.2% vs. 27.9%, 55.8% vs. 62.8%, and 58.1% vs. 55.8%, respectively. UTE demonstrates substantial diagnostic performance for SSCC in the pharynx and esophagus.

Coordinated phosphate uptake by extracellular alkaline phosphatase and solute carrier transporters in marine diatoms.

Marine diatoms express genes encoding potential phosphate transporter and alkaline phosphatase (APase) under phosphate-limited (-P) condition. This indicates that diatoms use high-affinity phosphate uptake system with organic phosphate hydration. The function of molecules playing roles for Pi uptake was determined in this study. Pi uptake and APase activity of two marine diatoms, Phaeodactylum tricornutum and Thalassiosira pseudonana, were monitored during acclimation to -P condition. The transcript levels of Pi transporter were analyzed, and Pi transporters were localized with GFP tagging in diatom cells. KO mutants of plasma membrane solute carrier proteins (SLC34s) or APase were established, and their phenotype was evaluated. Some Na+ /Pi transporter candidates, SLC34s in P. tricornutum and T. pseudonana, increased transcript under -P condition. Whole-cell Pi transport was specifically stimulated by sodium ion but independent of potassium, lithium, or proton. Genome-editing KO of PtSLC34-5 and APase (Pt49678) in P. tricornutum was highly inhibitory for Pi uptake, and KO of TpSLC34-2 was also highly inhibitory for Pi uptake in T. pseudonana. SLC34s and APase were co-expressed under -P conditions in marine diatoms. SLC34s play a major role in the initial acclimation stage of diatom cells to -P condition and APase plays an increasing role in the prolonged Pi-starved condition.

Texture and color enhancement imaging improves the visibility of gastric neoplasms: clinical trial with image catalogue assessment using conventional and newly developed endoscopes.

BACKGROUND: Texture and color enhancement imaging (TXI) enhances the changes in endoscopic features caused by gastric neoplasms, such as redness/whiteness and elevation/depression. This study aimed to demonstrate the effectiveness of TXI in improving the visibility of gastric neoplasms compared with white light imaging (WLI) using conventional (CE) and newly developed endoscopes (NE). METHODS: We recruited patients who were histologically diagnosed with gastric neoplasms; endoscopy was performed, and gastric neoplasms photographed using three imaging modalities, including WLI, TXI mode 1 (TXI-1) and TXI mode 2 (TXI-2). Two different endoscopes (CE and NE) were used for the same patients. Six endoscopists provided the visibility scale scores ranging from 1 (poor) to 4 (excellent) for gastric neoplasms. The primary outcome was the visibility scale scores based on each modality and endoscope. The secondary outcome was the identification of factors including H. pylori infection, atrophy, location, size, morphology, histological diagnosis and intestinal metaplasia that affect the differences in visibility scale scores between TXI-1/TXI-2 and WLI. RESULTS: Fifty-two gastric neoplasms were analyzed. The mean visibility scale scores with the NE were 2.79 ± 1.07, 3.23 ± 0.96 and 3.14 ± 0.92 for WLI, TXI-1 and TXI-2, respectively. The mean visibility scales with the CE were 2.53 ± 1.10, 3.04 ± 1.05 and 2.96 ± 1.92 for WLI, TXI-1 and TXI-2, respectively. For both endoscopes, significant differences were observed in visibility scale scores between WLI and TXI-1 (p < 0.001) and between WLI and TXI-2 (p < 0.001). The visibility scale scores of NE were superior to those of CE in all modalities. In the secondary outcome, there was no factor affected the differences of visibility scale scores between TXI-1/TXI-2 and WLI. CONCLUSIONS: This study demonstrated that TXI-1 and TXI-2 enhanced the visibility scale scores of gastric neoplasms compared with that of WLI. Moreover, newly developed endoscope has the potential to improve visibility compared to conventional endoscope. TRIAL REGISTRATION: This study was registered with the University Hospital Medical Information Network (UMIN000042429, 16/11/2020).

Mechanically Induced Anisotropic Fragments in Sn-Doped In2O3 Nanoparticle Films for Flexible Strain Sensing Based on Surface Plasmons.

Recently, mechanical strain sensors have been extensively developed to quantify large mechanical deformations for stretchable and wearable applications. In this study, we propose a plasmonic strain sensor based on the mechanical control of optical properties using an assembled film comprising In2O3: Sn nanoparticles (ITO NP film). The resonant reflectance in the infrared range could effectively be tuned by applying strain to the ITO NP film deposited on an elastomeric polydimethylsiloxane (PDMS) sheet. The change in reflectance was caused by the mechanical deformation of the PDMS sheet. The operating mechanism of the proposed plasmonic strain sensor was related to anisotropic fragments induced by cracks formed perpendicular to the direction of the applied strain. These anisotropic fragments were functionalized as optical modulators to change the reflectance depending on the applied strain. The sensing performance of the proposed plasmonic strain sensor was evaluated by using a PDMS sheet with a circular hole that produced nonuniform stress distributions. Finally, to evaluate the flexible and wearable performance of the proposed sensor, the optical detection of human motion was performed by detecting joint-related movements. The optical detection of human motion could be achieved because a change in motion (e.g., bending and stretching of the index finger) was reversibly associated with reflectance changes. Therefore, this study provides new insights into plasmon-based strain sensing for various applications in flexible instruments and human motion detection.

Sarcopenia Is a Prognostic Factor in Patients Undergoing Percutaneous Endoscopic Gastrostomy.

(1) Background: Percutaneous endoscopic gastrostomy (PEG) is a widely used long-term enteral nutrition method, but little is known about the associated prognostic factors in patients with PEG. Sarcopenia, a condition characterized by a loss of skeletal muscle mass, increases the risk of developing various gastrointestinal disorders. Yet, the relationship between sarcopenia and the prognosis after PEG remains unclear. (2) Methods: We conducted a retrospective study of patients who underwent PEG consecutively from March 2008 to April 2020. We analyzed preoperative sarcopenia and the prognosis of patients after PEG. We defined sarcopenia as a skeletal muscle index at the level of the third lumbar vertebra of ≤29.6 cm2/m2 for women and ≤36.2 cm2/m2 for men. Cross-sectional computed tomography images of skeletal muscle at the level of the third lumbar vertebra were evaluated using DICOM image analysis software (OsiriX). The primary outcome was the difference in overall survival after PEG based on the status of sarcopenia. We also performed a covariate balancing propensity score matching analysis. (3) Results: Of 127 patients (99 men, 28 women), 71 (56%) were diagnosed with sarcopenia, and 64 patients died during the observation period. The median follow-up period did not differ between patients with and without sarcopenia (p = 0.5). The median survival time after PEG was 273 days in patients with sarcopenia and 1133 days in those without (p < 0.001). Cox proportional hazard model analyses identified three factors that were significantly associated with overall survival: sarcopenia (adjusted hazard ratio [HR]: 2.9, 95% confidence interval [CI]: 1.6-5.4, p < 0.001), serum albumin level (adjusted HR: 0.34, 95% CI: 0.21-0.55, p < 0.001) and male sex (adjusted HR: 2.0, 95% CI: 1.1-3.7, p = 0.03). Propensity score-matched analysis (n = 37 vs. 37) showed that the survival rate was lower in the sarcopenia group than in the non-sarcopenia group (at 90 days: 77% (95% CI, 59-88) vs. 92% (76-97), at 180 days: 56% (38-71) vs. 92% (76-97), and at one year: 35% (19-51) vs. 81% (63-91), p = 0.0014). (4) Conclusions: Sarcopenia was associated with poor prognosis in patients having undergone PEG.

Multiple plasma membrane SLC4s contribute to external HCO3- acquisition during CO2 starvation in the marine diatom Phaeodactylum tricornutum.

The availability of CO2 is one of the restrictions on aquatic photosynthesis. Solute carrier (SLC) 4-2, a plasma membrane HCO3- transporter has previously been identified in the marine diatom Phaeodactylum tricornutum. In this study, we discovered two paralogs, PtSLC4-1 and PtSLC4-4, that are both localized at the plasma membrane. Their overexpression stimulated HCO3- uptake, and this was inhibited by the anion channel blocker 4,4´-diisothiocyanostilbene-2,2´-disulfonic (DIDS). Similarly to SLC4-2, PtSLC4-1 specifically required Na+ of ~100 mM for its maximum HCO3- transport activity. Unlike PtSLC4-1 and PtSLC4-2, the HCO3- transport of PtSLC4-4 depended equally on Na+, K+, or Li+, suggesting its broad selectivity for cations. Transcript analyses indicated that PtSLC4-1 was the most abundant HCO3- transporter under CO2 concentrations below atmospheric levels, while PtSLC4-4 showed little transcript induction under atmospheric CO2 but transient induction to comparable levels to PtSLC4-1 during the initial acclimation stage from high CO2 (1%) to very low CO2 (<0.002%). Our results strongly suggest a major HCO3- transport role of PtSLC4-1 with a relatively minor role of PtSLC4-2, and that PtSLC4-4 operates under severe CO2 limitation unselectively to cations when the other SLC4s do not function to support HCO3- uptake.

Analysis of the variation in learning curves for achieving competency in convex EUS training: a prospective cohort study using a standardized assessment tool.

BACKGROUND AND AIMS: The need for mastering standard imaging techniques for convex EUS in the biliopancreatic regions has been increasing; however, large variations in the aptitude for achieving EUS competency hinder expert development. Therefore, we investigated the factors influencing the achievement of expert competency in EUS using a new assessment tool for multiple imaging items. METHODS: Between January 2018 and February 2022, 3277 consecutive EUS procedures conducted by 5 beginners (EUS procedures <250), 7 intermediate trainees (250-749), and 2 experts (≥750) were prospectively evaluated. Immediately after each EUS procedure, the success or failure of imaging for each item was recorded using a newly developed EUS assessment tool that requires 17 items to be photographed. After correcting for missing values using multiple imputation, learning curves of EUS scores were created, and a competency was set based on expert scores. Finally, a comparative analysis between high and low performers was performed to extract factors influencing EUS scores. RESULTS: Although 3 of 7 intermediates (43%; mean, 317 cases) achieved competency, none of the beginners achieved competency. During a comparative analysis, although no significant difference in the number of EUS procedures performed was observed between the high and low performers, the former had significantly higher scores in the written test (theoretical knowledge). CONCLUSIONS: Our results showed that theoretical knowledge, rather than the number of EUS cases, may be a possible influencing factor for distinguishing high and low performers after treating 250 cases. (Clinical trial registration number: UMIN 000043271.).

The Advantage of Immunohistochemical Staining for Evaluating Lymphovascular Invasion Is Limited for Patients with Esophageal Squamous Cell Carcinoma Invading the Muscularis Mucosa.

The cumulative metastasis rate of esophageal squamous cell carcinoma (ESCC) pathologically invading the muscularis mucosae (pT1a-MM), based on lymphovascular invasion (LVI) evaluated by immunohistochemical (IHC) staining is unknown. This retrospective study included patients with endoscopically resected pT1a-MM ESCC. The primary endpoint was the metastasis rate of pT1a-MM based on LVI, evaluated using IHC and additional prophylactic therapy. The secondary endpoint was the identification of independent factors for metastasis based on lesion characteristics. The prognosis was also analyzed considering the impact of head and neck cancer. A total of 104 patients were analyzed, with a median follow-up of 74 months. The positive rate for LVI was 43.3% (45/104). In 33 patients, IHC was not performed at the time of clinical evaluation, 8 of whom exhibited LVI. However, these patients did not exhibit metastasis. The metastasis rates of patients without LVI, those with LVI and additional therapy, and those with LVI without additional therapy were 5.1%, 20.8%, and 0%, respectively. Lesion size ≥ 25 mm was the only independent factor for metastasis in multivariate analysis. The advantage of IHC for determining additional prophylactic therapy is limited for patients with pT1a-MM ESCC.

Infrared Plasmonic Metamaterials Based on Transparent Nanoparticle Films of In2O3:Sn for Solar-Thermal Shielding Applications.

Three-dimensional nanoparticle (NP) assemblies show interesting optical responses that differ from naturally occurring materials, such as metals, oxides, and semiconductors. In this study, we investigate the optical response of thin films comprising Sn:In2O3 NPs (ITO NP films) based on the correlation between complex permittivity and infrared (IR) reflectance for solar-thermal shielding applications. IR ellipsometry measurements are conducted to clarify the presence of Lorentz resonances in plasmonic metamaterials. The Lorentz resonances are correlated to the electric field strength at interparticle gaps by varying the Sn dopant concentration, as confirmed using finite-difference time-domain (FDTD) simulations. High solar-thermal shielding performance was obtained owing to selective near-IR reflection based on strong Lorentz resonances as the ITO NP films were electrically polarizable but magnetically inactive. Thermal shielding efficiency was demonstrated via a comparison of the air temperature change in a simulated box used as a model house. Additionally, we demonstrate the significance of NP packing density on the enhancement of the near-IR reflectance. The role of interparticle spacing for high near-IR reflectance was revealed by comparing effective medium approximation analyses and FDTD simulations. This relationship was also demonstrated by the reduction of solar-thermal shielding performance when using aggregated ITO NPs. Our work confirmed that the control of complex permittivity in plasmonic metamaterials must be considered in the structural design of transparent and reflective materials for solar-thermal shielding applications.

Diagnostic Dilemma of Biliopancreatic Contrast-Enhanced Harmonic Endoscopic Ultrasonography.

Background: The utility of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) alone in the biliopancreatic region appears to be limited because it is highly dependent on the experience and skill of the endoscopist. Therefore, the present study aimed to validate the efficacy of CH-EUS in clinical practice. Methods: Between January 2018 and March 2019, 301 consecutive patients who underwent CH-EUS were prospectively enrolled in this study. The diagnostic performance of CH-EUS was compared with that of dynamic computed tomography (CT), magnetic resonance imaging (MRI), and all combinations (i.e., CH-EUS, dynamic CT, and MRI) using a Bonferroni correction. A multiple logistic regression analysis was performed to extract each disease that allowed the CH-EUS diagnosis to be consistent with the final diagnosis. Results: In multiple comparisons of diagnostic performance, no significant differences were observed among dynamic CT, MRI, and CH-EUS (p = 1.00), but the diagnostic performance was significantly higher when all modalities were combined (p < 0.001). Moreover, only intraductal papillary mucinous neoplasm comprising adenoma or carcinoma (IPMN, n = 161) showed significance with respect to the agreement with the final diagnosis (p = 0.006). Conclusions: Our results showed that CH-EUS-based diagnosis of IPMN may be possible in clinical practice. On the contrary, to accurately diagnose biliopancreatic diseases other than IPMN, comprehensive diagnosis using multiple modalities may be necessary, rather than relying on CH-EUS alone.

International remote collaboration enabled inaugural endoscopic sleeve gastroplasty in Japan.

Obesity causes multiple conditions such as type 2 diabetes, cardiovascular disease, and so on, and an intervention is needed for controlling weight and improving metabolic syndrome. However, the effectiveness of lifestyle interventions and pharmacotherapy are restrictive for losing weight. Endoscopic sleeve gastroplasty (ESG) was developed as a new therapy, picking the best of both medication and surgery, less invasive and more effective. Recently, ESG is gradually spreading in Western countries, but there is Case report doesn't need conclusion/result for Japanese patients. We herein reported the first clinical case of ESG in Japan. Given the situation of the pandemic of COVID-19, we could not invite a proctor from Western countries and receive the instruction of the device setting and maneuver face to face. Thus, we conducted the training for device setting, maneuver, and operation under a web-based international remote collaboration. Eventually, we completed ESG without an adverse event. We could prove this web-based proctor system was useful through the introduction of ESG in Japan. The international remote collaboration could become a new normal even in the endoscopy field post-COVID-19 era.

Visibility evaluation of colorectal lesion using texture and color enhancement imaging with video.

Objective: To evaluate the visibility of colorectal lesions using a novel image processing algorithm, texture and color enhancement imaging (TXI), that allows the acquisition of brighter images with enhanced color and surface structure. Methods: During August-September 2019, patients referred for endoscopic treatment were prospectively recruited. Electronic data acquired while observing colorectal lesions using white light imaging (WLI) were obtained and recorded: WLI, TXI mode1 (with color enhancement), and TXI mode2 (without color enhancement) videos were constructed. The lesions were also recorded using narrow-band imaging (NBI) from the same perspective as WLI. Four video clips (WLI, TXI mode1, TXI mode2, and NBI) were made per lesion. Thereafter, video files for evaluations were prepared by randomly arranging all video clips. Finally, visualization scores were evaluated by four endoscopists, and the WLI, TXI mode1, TXI mode2, and NBI results were compared. Results: Overall, 22 patients with 68 lesions were recruited; the video file for evaluation subsequently comprised 272 randomly arranged video clips. Mean visualization scores using WLI, TXI mode1, TXI mode2, and NBI were 70.0 (±20.1), 80.5 (±18.6), 75.6 (±18.1), and 69.0 (±20.6), respectively. Mean visualization scores for flat lesions using WLI, TXI mode1, TXI mode2, and NBI were 64.1 (±21.2), 76.5 (±20.18), 71.8 (±19.4), and 64.2 (±22.0), respectively. Visualization scores using TXI mode1 were significantly better than those using WLI, TXI mode2, or NBI. Conclusions: TXI enables improved visualization of colorectal lesions, even flat lesions, than WLI and NBI. TXI may allow better detection of colorectal lesions, although further prospective studies are required.

Multi-loop traction device facilitates gastric endoscopic submucosal dissection: ex vivo pilot study and an inaugural clinical experience.

BACKGROUND: Endoscopic submucosal dissection (ESD) is technically difficult and requires considerable training. The authors have developed a multi-loop traction device (MLTD), a new traction device that offers easy attachment and detachment. We aimed to evaluate the utility of MLTD in ESD. METHODS: This ex vivo pilot study was a prospective, block-randomized, comparative study of a porcine stomach model. Twenty-four lesions were assigned to a group that undertook ESD using the MLTD (M-ESD group) and a group that undertook conventional ESD (C-ESD group) to compare the speed of submucosal dissection. In addition, the data of consecutive 10 patients with eleven gastric lesions was collected using electronic medical records to clarify the inaugural clinical outcomes of gastric ESD using MLTD. RESULTS: The median (interquartile range) speed of submucosal dissection in the M-ESD and C-ESD groups were 141.5 (60.9-177.6) mm2/min and 35.5 (20.8-52.3) mm2/min, respectively; submucosal dissection was significantly faster in the M-ESD group (p < 0.05). The rate of en bloc resection and R0 resection was 100% in both groups, and there were no perforation in either group. The MLTD attachment time was 2.5 ± 0.9 min and the MLTD extraction time was 1.0 ± 1.1 min. Clinical outcomes of MLTD in gastric ESD were almost the same as those of ex vivo pilot study. CONCLUSIONS: MLTD increased the speed of submucosal dissection in ESD and was similarly effective when used by expert and trainee endoscopists without perforation. MLTD can potentially ensure a safer and faster ESD.

Characteristics of superficial esophageal squamous cell carcinomas undetectable with narrow-band imaging endoscopy.

BACKGROUND: The detection rate of narrow-band imaging (NBI) for superficial esophageal squamous cell carcinoma (SESCC), including high-grade intraepithelial neoplasia, is significantly higher than that of white-light endoscopy. However, there are SESCCs that are undetectable by NBI but detectable by Lugol chromoendoscopy (LCE) and the characteristics of these SESCCs are still unknown. Thus, this study aimed to clarify the characteristics of SESCC that are undetectable using NBI. METHODS: Patients with current SCC or a history of SCC in the head and neck or in the esophagus were enrolled. The inspection of the esophagus was initiated by NBI, followed by LCE. Biopsies were taken of all suspected SESCC lesions during NBI observation and Lugol-voiding lesions (LVLs) that were irregularly shaped and >5 mm and/or pink in color during LCE observation. The characteristics of SESCC that were undetectable with NBI were statistically analysed. RESULTS: Overall, 147 lesions in 105 cases were histologically diagnosed as SESCC. Twenty in 15 cases were NBI-undetectable lesions, all of which were macroscopic flat type (0-IIb). The median sizes of the NBI-undetectable lesions and NBI-detectable lesions were both 15 mm (P = 0.47). Multivariate analysis revealed independent factors for NBI-undetectable lesions such as numerous irregularly shaped LVLs (odds ratio [OR]: 4.94, 95% confidence interval [CI]: 1.39-17.5, P < 0.05) and anterior wall position (OR: 4.99, 95% CI: 1.58-15.8, P < 0.05). CONCLUSIONS: The detection of SESCCs with NBI is challenging when lesions are morphologically completely flat, in cases with numerous irregularly shaped LVLs, and if located at the anterior wall.

Detection Accuracy and Latency of Colorectal Lesions with Computer-Aided Detection System Based on Low-Bias Evaluation.

We developed a computer-aided detection (CADe) system to detect and localize colorectal lesions by modifying You-Only-Look-Once version 3 (YOLO v3) and evaluated its performance in two different settings. The test dataset was obtained from 20 randomly selected patients who underwent endoscopic resection for 69 colorectal lesions at the Jikei University Hospital between June 2017 and February 2018. First, we evaluated the diagnostic performances using still images randomly and automatically extracted from video recordings of the entire endoscopic procedure at intervals of 5 s, without eliminating poor quality images. Second, the latency of lesion detection by the CADe system from the initial appearance of lesions was investigated by reviewing the videos. A total of 6531 images, including 662 images with a lesion, were studied in the image-based analysis. The AUC, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 0.983, 94.6%, 95.2%, 68.8%, 99.4%, and 95.1%, respectively. The median time for detecting colorectal lesions measured in the lesion-based analysis was 0.67 s. In conclusion, we proved that the originally developed CADe system based on YOLO v3 could accurately and instantaneously detect colorectal lesions using the test dataset obtained from videos, mitigating operator selection biases.

Reducing adenoma miss rate of colonoscopy assisted by artificial intelligence: a multicenter randomized controlled trial.

BACKGROUND: We have developed the computer-aided detection (CADe) system using an original deep learning algorithm based on a convolutional neural network for assisting endoscopists in detecting colorectal lesions during colonoscopy. The aim of this study was to clarify whether adenoma miss rate (AMR) could be reduced with CADe assistance during screening and surveillance colonoscopy. METHODS: This study was a multicenter randomized controlled trial. Patients aged 40 to 80 years who were referred for colorectal screening or surveillance at four sites in Japan were randomly assigned at a 1:1 ratio to either the "standard colonoscopy (SC)-first group" or the "CADe-first group" to undergo a back-to-back tandem procedure. Tandem colonoscopies were performed on the same day for each participant by the same endoscopist in a preassigned order. All polyps detected in each pass were histopathologically diagnosed after biopsy or resection. RESULTS: A total of 358 patients were enrolled and 179 patients were assigned to the SC-first group or CADe-first group. The AMR of the CADe-first group was significantly lower than that of the SC-first group (13.8% vs. 36.7%, P < 0.0001). Similar results were observed for the polyp miss rate (14.2% vs. 40.6%, P < 0.0001) and sessile serrated lesion miss rate (13.0% vs. 38.5%, P = 0.03). The adenoma detection rate of CADe-assisted colonoscopy was 64.5%, which was significantly higher than that of standard colonoscopy (53.6%; P = 0.036). CONCLUSION: Our study results first showed a reduction in the AMR when assisting with CADe based on deep learning in a multicenter randomized controlled trial.

Artificial intelligence in endoscopy: Present and future perspectives.

Artificial intelligence (AI) has been attracting considerable attention as an important scientific topic in the field of medicine. Deep-leaning (DL) technologies have been applied more dominantly than other traditional machine-learning methods. They have demonstrated excellent capability to retract visual features of objectives, even unnoticeable ones for humans, and analyze huge amounts of information within short periods. The amount of research applying DL-based models to real-time computer-aided diagnosis (CAD) systems has been increasing steadily in the GI endoscopy field. An array of published data has already demonstrated the advantages of DL-based CAD models in the detection and characterization of various neoplastic lesions, regardless of the level of the GI tract. Although the diagnostic performances and study designs vary widely, owing to a lack of academic standards to assess the capability of AI for GI endoscopic diagnosis fairly, the superiority of CAD models has been demonstrated for almost all applications studied so far. Most of the challenges associated with AI in the endoscopy field are general problems for AI models used in the real world outside of medical fields. Solutions have been explored seriously and some solutions have been tested in the endoscopy field. Given that AI has become the basic technology to make machines react to the environment, AI would be a major technological paradigm shift, for not only diagnosis but also treatment. In the near future, autonomous endoscopic diagnosis might no longer be just a dream, as we are witnessing with the advent of autonomously driven electric vehicles.

Blood group O is a risk factor for delayed post-polypectomy bleeding.

BACKGROUND: Blood group O of ABO blood group system is considered as a risk factor for various bleeding events, but the relationship with endoscopic treatment-associated bleeding has yet to be investigated. This study aimed to evaluate whether blood group O is associated with delayed bleeding after colorectal endoscopic resection. METHODS: This was a retrospective observational study based on medical records at four university hospitals in Japan. We reviewed the records for consecutive patients who underwent colorectal endoscopic resection from January 2014 through December 2017. The primary outcome was the incidence of delayed bleeding, defined as hematochezia or melena, requiring endoscopy, transfusion, or any hemostatic intervention up to 28 days after endoscopic resection. Multivariate logistic regression analysis was performed to adjust the impact of blood group O on the delayed bleeding. RESULTS: Among 10,253 consecutive patients who underwent colorectal endoscopic resection during the study period, 8625 patients met the criteria. In total, delayed bleeding occurred in 255 patients (2.96%). The O group had significantly more bleeding events compared with the non-O group (A, B, and AB) (relative risk, 1.62 [95% confidence interval, 1.24-2.10]; P < 0.001). In multivariate logistic regression analysis, blood group O remained an independent risk factor for the bleeding (adjusted odds ratio, 1.60 [95% confidence interval, 1.18-2.17]; P = 0.002). CONCLUSIONS: Blood group O was associated with an increased risk of delayed bleeding in patients undergoing colorectal endoscopic resection. Preoperative screening for ABO blood group could improve risk assessments.

Fabrication of Infrared-Compatible Nanofluidic Devices for Plasmon-Enhanced Infrared Absorption Spectroscopy.

Nanofluidic devices have offered us fascinating analytical platforms for chemical and bioanalysis by exploiting unique properties of liquids and molecules confined in nanospaces. The increasing interests in nanofluidic analytical devices have triggered the development of new robust and sensitive detection techniques, especially label-free ones. IR absorption spectroscopy is one of the most powerful biochemical analysis methods for identification and quantitative measurement of chemical species in the label-free and non-invasive fashion. However, the low sensitivity and the difficulties in fabrication of IR-compatible nanofluidic devices are major obstacles that restrict the applications of IR spectroscopy in nanofluidics. Here, we realized the bonding of CaF2 and SiO2 at room temperature and demonstrated an IR-compatible nanofluidic device that allowed the IR spectroscopy in a wide range of mid-IR regime. We also performed the integration of metal-insulator-metal perfect absorber metamaterials into nanofluidic devices for plasmon-enhanced infrared absorption spectroscopy with ultrahigh sensitivity. This study also shows a proof-of-concept of the multi-band absorber by combining different types of nanostructures. The results indicate the potential of implementing metamaterials in tracking several characteristic molecular vibrational modes simultaneously, making it possible to identify molecular species in mixture or complex biological entities.

Intra-abdominal pressure during endoscopic full-thickness resection comparing manual and automatic control insufflation: a block-randomized porcine study.

BACKGROUND AND STUDY AIMS: An automatic carbon dioxide (CO2) insufflating system (SPACE) was developed to stabilize intra-lumenal pressure (ILP) during endoscopic interventions. This study investigated whether SPACE could improve the control and monitoring of extra-lumenal intra-abdominal pressure (IAP) after establishing a perforation during endoscopic full-thickness resection (EFTR) of the gastric wall in porcine models. MATERIALS AND METHODS: After first establishing the optimal preset pressure for gastric EFTR in four pigs, we compared IAP dynamics during EFTR between manual insufflation and SPACE using a block-randomized study (n = 10). IAP was percutaneously monitored and plotted on a timeline graph every 5 s. The maximal IAP and the area under the IAP curve exceeding 10 mmHg (AUC≥10 mmHg) were compared between groups, with the agreement between IAP and endolumenally monitored ILP also analyzed for animals in the SPACE group. RESULTS: In the first study, 8 mmHg was identified as the most preferable preset pressure after establishment of the perforation. In the randomized study, the mean maximal IAP in the SPACE group was significantly lower than that in the manual insufflation group (11.0 ± 2.0 mmHg vs. 17.0 ± 3.5 mmHg; P = 0.03). The mean AUC≥10 mmHg was also significantly smaller in the SPACE group. Bland-Altman analysis demonstrated agreement between IAP and ILP within a range of ± 1.0 mmHg. CONCLUSIONS: SPACE could be used to control and safely monitor IAP during gastric EFTR by measuring ILP during perforation of the gastric wall.