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Background: Activin A receptor type 2A (ACVR2A) is one of the most frequently mutated genes in microsatellite instability-high (MSI-H) gastric cancer. However, the clinical relevance of the ACVR2A mutation in MSI-H gastric cancer patients remains unclear. The aims of this study were to explore the effect of ACVR2A mutation on the tumor behavior and to identify the clinicopathological characteristics of gastric cancer patients with ACVR2A mutations. Methods: An in vitro study was performed to investigate the biological role of ACVR2A via CRISPR/Cas9-mediated ACVR2A knockout MKN74 human gastric cancer cells. One hundred twenty-four patients with gastric cancer were retrospectively analyzed, and relations between MSI status, ACVR2A mutations, and clinicopathological factors were evaluated. Results: ACVR2A knockout cells showed less aggressive tumor biology than mock-transfected cells, displaying reduced proliferation, migration, and invasion (P < 0.05). MSI mutations were found in 10% (13/124) of gastric cancer patients, and ACVR2A mutations were found in 8.1% (10/124) of patients. All ACVR2A mutations were accompanied by MSI. The 5-year overall survival rates of ACVR2A wild-type patients and ACVR2A-mutated patients were 57% and 90%, respectively (P = 0.048). Multivariate analysis revealed that older age (P = 0.015), distant metastasis (P < 0.001), and ACVR2A wild-type status (P = 0.040) were independent prognostic factors for overall survival. Conclusions: Our study demonstrated that gastric cancer patients with ACVR2A mutation have a significantly better prognosis than those without. Dysfunction of ACVR2A in MKN74 human gastric cancer cells caused less aggressive tumor biology, indicating the importance of ACVR2A in the progression of MSI-H tumors. [ABSTRACT FROM AUTHOR] more...

Summary Background and aims Transthoracic esophagectomy using 3-field lymphadenectomy (TTE-3FL) for esophageal cancer is one of the most aggressive gastrointestinal surgeries. Early enteral nutrition (EN) for TTE-3FL patients is useful and valid for early recovery; however, EN using a fat-containing formula risks inducing chyle leak. In the present study, we retrospectively examined esophageal cancer patients treated byTTE-3FL and administered postoperative EN to elucidate the validity of lowering the fat levels in elemental formulas to prevent postoperative chyle leak and improve postoperative recovery. Methods A total of 74 patients who received TTE-3FL for esophageal cancer were retrospectively examined. Patients were classified into two groups according to the type of postoperative EN: Group LF patients received a low-fat elemental formula, and Group F patients received a standard fat-containing polymeric formula. The following clinical factors were compared between the groups: EN start day, maximum EN calories administered, duration of respirator use, length of ICU stay, incidence of postoperative infectious complications, use of parenteral nutrition (PN), and incidence of postoperative chyle leak. Results Patients in Group LF were started on EN significantly earlier after surgery and they consumed significantly higher maximum EN calories compared to Group F patients ( P < 0.01). Duration of respirator use and length of ICU stay were also significantly shorter, and TPN was used significantly less in Group LF compared to Group F ( P < 0.05). Postoperative chyle leak was observed in six patients in total (8.1%); five patients in Group F and one patient in Group LF, although there was no significant difference in frequency of chyle leak per patient between Group LF and Group F. Conclusions Early EN using low-fat elemental formula after esophagectomy with three-field lymphadenectomy was safe and valid for postoperative recovery and potentially useful in preventing chyle leak. [ABSTRACT FROM AUTHOR] more...

Abstract: The present study was designed to show the applicability of scanning ion conductance microscopy (SICM) for imaging different types of biological samples. For this purpose, we first applied SICM to image collagen fibrils and showed the usefulness of the approach-retract scanning (ARS)/hopping mode for such samples with steep slopes. Comparison of SICM images with those obtained by AFM revealed that the ARS/hopping SICM mode can probe the surface topography of collagen fibrils and chromosomes at nanoscale resolution under liquid conditions. In addition, we successfully imaged cultured HeLa cells, with 15μm in height by ARS/hopping SICM mode. Because SICM can obtain non-contact (or force-free) images, delicate cellular projections were visualized on the surface of the fixed cell. SICM imaging of live HeLa cells further demonstrated its applicability to study the morphological dynamics associated with biological processes on the time scale of minutes under liquid conditions. We further applied SICM for imaging the luminal surface of the trachea and succeeded in visualizing the surface of both ciliated and non-ciliated cells. These SICM images were comparable with those obtained by scanning electron microscopy. Although the dynamic mode of AFM provides better resolution than the ARS/hopping mode of SICM in some samples, only the latter can obtain contact-free images of samples with steep slopes, rendering it an important tool for observing live cells as well as unfixed or fixed soft samples with complicated shapes. Taken together, we demonstrate that SICM imaging, especially using an ARS/hopping mode, is a useful technique with unique capabilities for imaging the three-dimensional topography of a range of biological samples under physiologically relevant aqueous conditions. [Copyright &y& Elsevier] more...

Abstract: Background: Craniofacial resection is regarded as the treatment of choice for paranasal malignant tumors invading the skull base. Even with this approach, the surgical view remains obscured when tumors in the deep nasal and paranasal sinuses are resected. Endoscopy provides a wide and clear surgical view in the deep and narrow nasal cavity. We report two patients who underwent craniofacial resection assisted with endoscope. Methods: Two patients with malignant paranasal sinus tumor invading the anterior skull base underwent endoscope-assisted craniofacial resection. Results: To avoid a limited surgical view in the sinonasal cavity, we performed craniofacial resection with endoscopic osteotomy and several procedures in the nasal cavity. The neurosurgeon performed anterior skull base osteotomy at an appropriate site from above, while the otolaryngologist provided illumination with the endoscope from below and preserved the adjacent structures. The patients recovered uneventfully and the endoscopic examinations of both patients 18 months after the surgery showed no recurrence. Conclusions: Endoscopes were useful for the craniofacial resection at osteotomy, providing illumination from below and at the several procedures in the deep part of the nasal cavity. If a lateral rhinotomy incision is made, the combined transfacial and transnasal approaches avoid the limited working angle associated with the transnasal approach alone. Although an endoscopic approach is useful for treating sinonasal tumors, we should recognize its advantages and limitations. [Copyright &y& Elsevier] more...

We report an extremely rare case of saccular thoracoabdominal aortic aneurysm associated with high abdominal aortic occlusion including the superior mesenteric and bilateral renal arteries in a patient requiring hemodialysis. Successful repair of the aneurysm and concomitant revascularization of the lower extremities was achieved using femoro-femoral bypass for perfusion of the lower body along with the visceral and intercostal arteries. [Copyright &y& Elsevier] more...

We report a very rare case of acute aortic dissection of the ascending aorta, which ruptured to the left pleural cavity through the left-side congenital pericardial defect. A preoperative computed tomographic scan and a roentgenogram showed localized dissection of the ascending aorta and severely deteriorating left hemothorax, which required emergency operation. Intraoperative findings revealed the ruptured aortic dissection of the ascending aorta and the defect at the left-side pericardium, and a graft replacement of the ascending aorta was performed. It was considered that congenital pericardial defect complicates the diagnosis in a case of catastrophic intrapericardial hemorrhage. [Copyright &y& Elsevier] more...

We report a case in which replacement of a Smeloff-Cutter aortic ball prosthesis was required 28 years after initial implantation. A 57-year-old woman underwent aortic valve replacement with a 21-mm Smeloff-Cutter ball prosthesis and open mitral commissurotomy for aortic stenosis, aortic regurgitation, and mitral stenosis in 1973. Severe aortic regurgitation occurred in April 2001, and aortic valve reoperation combined with mitral valve replacement was successfully performed. The patient’s aortic ball valve was nearly intact with perivalvular leakage probably causing the aortic regurgitation. Our experience documents longer durability for the Smeloff-Cutter prosthesis than has been reported to date. [Copyright &y& Elsevier] more...

We describe a new technique of mitral valve repair based on two reconstructive techniques: (1) the folding leaflet method, and (2) the classic annular plication. This combination appears to be useful in cases with a large prolapsing posterior mitral leaflet with excessive leaflet height or in cases with commissural prolapse involving both the anterior and posterior leaflets. [Copyright &y& Elsevier] more...

We report two cases of acute subdural hematoma after cardiac surgery using cardiopulmonary bypass. In both patients, emergency removal and drainage of a subdural hematoma was performed by neurosurgeons, and complete recovery followed. Subdural hemorrhagic brain injury after cardiac surgery is rare and devastating; however, we consider early diagnosis and proper treatment to be effective because organic brain damage did not occur. [Copyright &y& Elsevier] more...

A surgical modification for safe early repair of posterior septal rupture is described. This technique is based on the method described by Daggett, but adds one internal patch, plus the application of fibrin glue between the internal and external patch for minimizing bleeding. This modification is a simple and reliable one for repairing posterior ventricular septal rupture. [Copyright &y& Elsevier] more...

Since a three-dimensional (3D) cellular ultrastructure is significant for biological functions, it has been investigated using various electron microscopic techniques. Although transmission electron microscopy (TEM)-based techniques are traditionally used, cells must be embedded in resin and sliced into ultrathin sections in sample preparation processes. Block-face observation using a scanning electron microscope (SEM) has also been recently applied to 3D observation of cellular components, but this is a destructive inspection and does not allow re-examination. Therefore, we developed electron tomography using a transmission electron imaging technique called Plate-TEM. With Plate-TEM, the cells cultured directly on a scintillator plate are inserted into a conventional SEM equipped with a Plate-TEM observation system, and their internal structures are observed by detecting scintillation light produced by electrons passing through the cells. This technology has the following four advantages. First, the cells cultured on the plate can be observed at electron-microscopic resolution since they remain on the plate. Second, both surface and internal information can be obtained simultaneously by using electron- and photo-detectors, respectively, because a Plate-TEM detector is installed in an SEM. Third, the cells on the scintillator plate can also be inspected using light microscopy because the plate has transparent features. Finally, correlative observation with other techniques, such as conventional TEM, is possible after Plate-TEM observation because Plate-TEM is a non-destructive analysis technique. We also designed a sample stage to tilt the samples for tomography with Plate-TEM, by which 3D organization of cellular structures can be visualized as a whole cell. In the present study, Mm2T cells were investigated using our tomography system, resulting in 3D visualization of cell organelles such as mitochondria, lipid droplets, and microvilli. Correlative observations with various imaging techniques were also conducted by successive observations with light microscopy, SEM, Plate-TEM, and conventional TEM. Consequently, the Plate-TEM tomography technique encourages understanding of cellular structures at high resolution, which can contribute to cellular biological research. [ABSTRACT FROM AUTHOR] more...