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Background/aim Cancer stem cells (CSCs) contribute to resistance against neoadjuvant chemotherapy (NAC) in esophageal squamous cell carcinoma (ESCC). We conducted a retrospective observational study for the relationship between the expression levels of CSC markers in biopsy specimens prior to 5-fluorouracil plus cisplatin (FP)-NAC and the pathological responses. Patients and methods We included 171 patients with ESCC who underwent the FP-NAC followed by radical resection. Biopsy specimens prior to the FP-NAC were obtained and immunochemically stained for CD44, CD133, and CD24. Results The biopsy specimens of the non-responders had the CD44high/CD24low expression at high levels, which was found as an independent predictor of not only FP-NAC resistance but also poor overall survival by multivariate analyses. Conclusion CD44high/CD24low expression in the biopsy specimens prior to FP-NAC may be a predictor of FP-NAC resistance and poor prognosis of ESCC patients.

No study has focused on the safety and feasibility of our previously developed open-window suturing technique to close mucosal defects on the pancreatic side after endoscopic submucosal dissection from the opened duodenal wall. This study aimed to evaluate the safety and usefulness of laparoscopic endoscopic cooperative surgery for duodenal tumors for treating superficial non-ampullary duodenal epithelial tumors on the pancreatic side of the duodenum.This retrospective study included 61 consecutive patients who underwent surgery during August 2014-November 2021. After dissection when the tumor was on the pancreatic side, we sutured the mucosal defect from the opened duodenal wall. A preoperative endoscopic pancreatic stent was placed for tumors within 1 cm of the ampulla of Vater. The surgical outcomes were compared between tumors on the pancreatic and non-pancreatic sides.There were 27 and 34 patients with tumors on the pancreatic and non-pancreatic sides, respectively. The patient characteristics were similar. Preoperative pancreatic stents were placed in four patients in the pancreatic side group. The median operative time was significantly longer on the pancreatic side than in the non-pancreatic side group (241 vs. 209 min, P = 0.02). In one patient in the pancreatic side group, an intraoperative injury of the ampulla of Vater was successfully treated with intraoperative management. There were no significant differences in the incidence of postoperative grade II or higher complications between the groups.Laparoscopic endoscopic cooperative surgery for duodenal tumors for treating superficial non-ampullary duodenal epithelial tumors on the pancreatic side is safe and feasible.

Background: Invariant natural killer T (iNKT) cells have been shown as an ideal immunotherapeutic target of which the activation via α-Galactosylceramide (α-Gal) conjugated with the MHC class 1-like CD1d molecule induces both innate and adaptive immune system. With transfection of antigen information, α-Gal loaded CD1d expressing cells can act as a vector to enhance the antigen specific immune responses. Though transfection of antigen information by using antigen coding mRNA or tumor peptide is common, the process of extracting mRNA or identifying tumor peptide is sometimes too complicated. Electroporation (EP) has been reported as a way to induce substances easily into cells. We applied EP as a simple method to deliver the antigen into the vector for iNKT cell activation.In this study, we aimed to show a feasibility of EP as a method to deliver the antigen into α-Gal loaded dendritic cells (DCs), a naturally CD1d expressing vector, in terms of inducing antigen specific antitumor responses and innate immunity. Methods: DCs were generated from bone marrow of C57BL/6 mice. Ovalbumin (OVA) was electroporated to DCs as a tumor model antigen. To load α-Gal, DCs were cultured with α-Gal for 24 hours before cultured with LPS. We compared the antitumor responses of α-Gal loaded DCs with or without electroporated OVA in C57BL/6 mice. In subcutaneous tumor model, mice were prophylactically administered each type of DCs intravenously followed by subcutaneous injection of EG7, which is OVA induced EL4, thymoma (n = 5). We evaluated the tumor size and the survival rate. We also evaluated the innate immunity which induced by α-Gal loaded DCs with or without electroporated OVA. Results: With electroporated OVA, tumors didn't grow in mice administered α-Gal loaded DCs whereas tumors in mice administered α-Gal loaded DCs without electroporated OVA aggressively progressed(P < 0.05). In mice administered α-Gal loaded DCs with electroporated OVA, no death was observed during the whole observation period. Survival rate was significantly better for mice administered α-Gal loaded DCs with electroporated OVA than those administered α-Gal loaded DCs without electroporated OVA(P < 0.05). On the other hand, α-Gal loaded DCs with or without electroporated OVA showed no difference in inducing NK cells. But, they either induced more NK cells than α-Gal unloaded DCs(P < 0.05). Conclusion: α-Gal loaded DCs with electroporated OVA showed significantly higher rate of tumor rejection and longer survival in the mice model inoculated OVA-induced tumor comparing to α-Gal loaded DCs without electroporated OVA. Also, EP didn't impair the ability of inducing innate immunity. EP was feasible as a way to deliver the antigen into the vector which induced antigen specific antitumor responses. We are trying to show the activity of antigen-specific cytotoxic T lymphocytes following the administration of α-Gal loaded DCs with electroporated antigen. Citation Format: Akihiro Watanabe, Kimihiro Yamashita, Akira Arimoto, Kouta Yamada, Kyosuke Agawa, Takashi Kamigaki, Rishu Takimioto, Yoshihiro Kakeji. Antigen electroporated DC loaded with NKT-cell ligand induces the antigen specific antitumor immunity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 698.

A man in his sixties with a medical history of diabetes and dyslipidemia was detected with a tumor with massive submucosal invasion on colonoscopy. He was diagnosed with sigmoid cancer and underwent laparoscopic sigmoid colectomy with D3 lymph node dissection. An electric surgical knife and an ultrasonically activated device was used to perform D3 lymph node dissection with preservation of the left colic artery(LCA)and division of the S1A and S2A. On postoperative day 4(POD4), 1 day after oral intake was started, chylous ascites began to develop. Owing to the small volume of ascites, oral feeding was continued, and chylous ascites was treated successfully with a low-fat diet. Chylous ascites immediately reduced on POD6, after which the drain was removed on POD7. He was discharged on POD9. Fasting and complete parenteral nutrition are not necessarily required in the treatment of chyle leakage after laparoscopic colorectal cancer surgery.

A 40's woman had a complaint of abdominal and back pain. Enhanced CT visualized a large retroperitoneal tumor and huge multiple myomas of the uterus. The tumor was 10cm in diameter and located in the anterior of the inferior vena cava, and progressed from the posterior of the duodenum to the abdominal aortic bifurcation. Diffusion-weighted MR image showed the tumor with high signal intensity. Upper gastrointestinal endoscopy revealed a type 2 tumor at the anal side of the Vater. The patient was performed curativly abdominal total hysterectomy and pancreaticoduodenectomy with inferior vena cava resection. Immunohistochemical examination showed that the tumor cells were negative for CD34 and c-kit, and positive for desmin and a-SMA. The tumor was histopathologically diagnosed as leiomyosarcoma originating from the duodenum.

In this paper, we discuss 3-dimensional reconstruction from multi-view images. In particular, we focus on SIFT[1] and AKAZE[2], well-known as keypoint detection/feature descriptor used for 3D reconstruction, and evaluate the performance of them. 3D reconstruction quality highly depends on the results of keypoint matching between images, so that it is important to evaluate the performance. First, this paper shows the results of keypoint matching by SIFT and AKAZE. Next, 3D reconstruction is performed based on each of the matching results, and the accuracy of 3D points is evaluated. We also use Multi View Stereo (CMVS[4]) to obtain dense 3D points. Moreover, in this study, we propose a new method for which SIFT and AKAZE are combined to obtain further detailed reconstruction, and show the better reconstruction results than the ones obtained by using only SIFT or AKAZE.

Device implantations may be challenging in patients with venous abnormalities. The most common congenital variation, frequently associated with other congenital abnormalities, is a persistent left superior vena cava (PLSVC), and successful atrial and ventricular lead implantation via a PLSVC have both been reported [1]. “Ratchet syndrome” has also been reported as a rare complication after a newly implanted pacemaker or implantable cardioverter-defibrillator (ICD) and involves lead dislodgement and retraction due to a ratchet-like movement through the suture sleeve that causes a continuous short pull [2], [3]. Here, we present a rare case in which successful dual-chamber ICD implantation via a PLSVC was achieved after the occurrence of ratchet syndrome.

The atrial conduction time measured by echocardiography using tissue Doppler imaging (TDI) has been reported as a predictive factor of left atrial (LA) remodeling. We investigated the P wave to LA appendage (LAA) conduction time defined by transthoracic echocardiography using TDI (P-LAA TDI), and directly compared the actual LA electrical conduction time determined by the electrophysiological data. Additionally, we confirmed the clinical utility of the P-LAA TDI by examining the relationship to the electroanatomical LA remodeling data. Sixty-three AF patients (22 paroxysmal AF, 41 persistent AF) underwent ablation and electroanatomical LA mapping. The P-LAA TDI was measured after the ablation and was compared with the electrophysiological data during sinus rhythm, including the actual electrical conduction time. A strong linear correlation (r = 0.776, p

A 51-year-old man was hospitalized because of close examination for liver dysfunction. drip infusion cholangiography-computed tomography (DIC-CT) revealed a stricture located at the middle bile duct but normal biliary scintigraphy. Endoscopic retrograde cholangiopancreatography (ERCP) showed obstruction of bile duct. Although we tried to pass the stricture using several kinds of guidewire under direct vision of peroral cholangioscopy, recanalization could not be achieved. Then percutaneous transhepatic biliary drainage (PTBD) was conducted. Cholangioscopy using narrow band imaging showed no tumor vessel or irregular mucosa. The biopsy specimens obtained from both distal and proximal sides of stricture showed no malignancy. Eventually, a rendezvous technique was tried using guidewire under percutaneous transhepatic cholangioscopy (PTCS) direct vision. Fortunately, since a guidewire could advance into a tiny hole at the center of a scar and an endoscopic nasobiliary drainage (ENBD) tube could be placed across the biliary stricture. One week after placement of ENBD tube, a 10 Fr plastic stent was inserted and the PTBD tube was removed without procedure-related complication. Eight months later, the stent was removed and the chief complaint disappeared without liver dysfunction.

Minimum Classification Error (MCE) training, which can be used to achieve minimum error classification of various types of patterns, has attracted a great deal of attention. However, to increase classification robustness, a conventional MCE framework has no practical optimization procedures like geometric margin maximization in Support Vector Machine (SVM). To realize high robustness in a wide range of classification tasks, we derive the geometric margin for a general class of discriminant functions and develop a new MCE training method that increases the geometric margin value. We also experimentally demonstrate the effectiveness of our new method using prototype-based classifiers.

計算機の性能や利用可能なデータ量に関する近年の著しい進歩に伴い,パターン分類器設計のための識別学習法に関する研究の関心が高まってきた.中でも,最小分類誤り学習(MCE)とサポート・ベクター・マシン(SVM)は大きな注目を集めている.前者は多様なタイプの音声分類器あるいはテキスト分類器のための汎用的な識別学習の枠組みとして広く用いられ,一方,後者は固定次元ベクトルの効果的な分類のための標準的な技術となっている.原理的には,MCEは最小誤り分類の達成を目指し,それとは対照的にSVMは分類決定における耐性の向上を目指す.これらの2つの異なる目標を同時に達成することができれば,明らかに有益な分類を実現できるものと考えられる.本論文は,こうした問題意識に立ち,MCEとSVMとの2つの方法論を詳細に分析し,最大幾何マージンと最小誤り分類との双方を実用的な枠組みにおいて同時に達成する新しいMCE訓練法を提案するものである., The recent dramatic growth of computation power and data availability has increased research interests in discriminative training methodologies for pattern classifier design. Minimum Classification Error (MCE) training and Support Vector Machine (SVM) training methods are especially attracting a great deal of attention. The former has been widely used as a general framework for discriminatively designing various types of speech and text classifiers; the latter has become the standard technology for the effective classification of fixed-dimensional vectors. In principle, MCE aims to achieve minimum error classification, and in contrast, SVM aims to increase the classification decision robustness. The simultaneous achievement of these two different goals would definitely valuable. Motivated this concern, in this paper we elaborate the MCE and SVM methodologies and develop a new MCE training method that leads in practice to the best condition of maximum geometric margin and minimum error classification.