Non-Equilibrium Electrons and the Sunyaev-Zel'dovich Effect of Galaxy Clusters

We present high-resolution cosmological hydrodynamic simulations of three galaxy clusters employing a two-temperature model for the intracluster medium. We show that electron temperatures in cluster outskirts are significantly lower than the mean gas temperature, because Coulomb collisions are insufficient to keep electrons and ions in thermal equilibrium. This deviation is larger in more massive and less relaxed systems, ranging from 5% in relaxed clusters to 30% for clusters undergoing major mergers. The presence of non-equilibrium electrons leads to significant suppression of the SZE signal at large cluster-centric radius. The suppression of the electron pressure also leads to an underestimate of the hydrostatic mass. Merger-driven, internal shocks may also generate significant populations of non-equilibrium electrons in the cluster core, leading to a 5% bias on the integrated SZ mass proxy during cluster mergers.Comment: 5 pages, 4 figures, Accepted for publication in ApJ

Cool core disturbed: Observational evidence for coexistence of sub-sonic sloshing gas and stripped shock-heated gas around the core of RX J1347.5-1145

RXJ1347.5-1145 (z = 0.451) is one of the most luminous X-ray galaxy clusters, which hosts a prominent cool core and exhibits a signature of a major merger. We present the first direct observational evidence for sub-sonic nature of sloshing motion of the cool core. We find that a residual X-ray image from the Chandra X-ray Observatory after removing the global emission shows a clear dipolar pattern characteristic of gas sloshing, whereas we find no significant residual in the Sunyaev-Zel'dovich effect (SZE) image from the Atacama Large Millimeter/submillimeter Array (ALMA). We estimate the equation of state of perturbations in the gas from the X-ray and SZE residual images. The inferred velocity is 420 +310 -420 km s-1, which is much lower than the adiabatic sound speed of the intracluster medium in the core. We thus conclude that the perturbation is nearly isobaric, and gas sloshing motion is consistent with being in pressure equilibrium. Next, we report evidence for gas stripping of an infalling subcluster, which likely shock-heats gas to high temperature well in excess of 20 keV. Using mass distribution inferred from strong lensing images of the Hubble Space Telescope (HST), we find that the mass peak is located away from the peak position of stripped gas with statistical significance of > 5{\sigma}. Unlike for the gas sloshing, the velocity inferred from the equation of state of the excess hot gas is comparable to the adiabatic sound speed expected for the 20 keV intracluster medium. All of the results support that the southeast substructure is created by a merger. On the other hand, the positional offset between the mass and the gas limits the self-interaction cross section of dark matter to be less than 3.7 h-1 cm2 g-1 (95% CL).Comment: 18 pages, 10 figures, accepted for publication in Ap

Usefulness of peripherally inserted central catheters

Introduction : Central venous catheter (CVC) use is essential for treating esophageal cancer. Peripherally inserted central catheters (PICC) are commonly used recently for improved patient comfort and safety. We compared centrally inserted central catheters (CICC) and PICC insertions and examined their safety. Methods : We retrospectively investigated complications at the catheter insertion and post-insertion for 199 patients’ esophageal cancer treatment (CICC : 45, PICC : 154) from 2013 to 2018. In addition, we summarized the results of catheter tip culture. Results : No serious complications occurred at the catheter insertion in either group. The rate of complications at catheter insertion was 5.8% for PICC and 6.7% for CICC patients. Post-insertion complications were observed in 6.5% and 11.1% of patients with PICC and CICC, respectively, and this difference was not significant. The incidence of catheter-related blood stream infection (CRBSI) was significantly lower in PICC than CICC patients (0.3 vs. 1.8 / 1,000 catheter-days ; p = 0.029). Catheter-related thrombosis was observed in PICC : 0.5 and CICC : 0.6, and occlusion due to blood flow reversal was observed in PICC : 0.5 and CICC : 0.6. Conclusion : PICCs are safer and more effective than CICCs for the treatment of esophageal cancer, and reduce the incidence of CRBSI. We hope to standardize the insertion procedures, conventionalize techniques, and establish training systems

ICG fluorescence for lung metastasis of HCC

Background: Indocyanine green (ICG) accumulates in hepatocellular carcinoma (HCC), and tumor fluorescence can be observed under irradiation with near infrared light (NIR). This study investigated the clinical utility of ICG fluorescence imaging during resection of pulmonary metastases of HCC. Methods: From April 2010 to June 2018, six patients with suspected pulmonary metastasis of HCC were enrolled prospectively. Prior to surgery, all patients underwent the ICG hepatic function test following intravenous administration of ICG (0.5 mg/kg body weight). During surgery, metastatic HCC was identified by observation of ICG fluorescence, allowing assessment of the surgical margin. Tumor fluorescence was also evaluated on cut sections. Results: A total of 11 metastatic HCCs were resected in six patients at nine operations. Eight lesions were removed by wedge resection and 3 lesions were managed by lobectomy. During surgery, tumor fluorescence could be confirmed through the visceral pleura in 6 out of 7 lesions treated by wedge resection, while NIR irradiation was difficult for 1 lesion. For these 6 lesions, the median distance from the tumor to the visceral pleura and the median surgical margin were 0 mm (range, 0–2 mm) and 14 mm (range, 11–17 mm), respectively. When cut sections were examined, all tumors emitted fluorescence. All lesions were histologically confirmed to be metastatic HCC. Conclusions: In patients with pulmonary metastasis of HCC, ICG fluorescence imaging is useful for identifying the tumor and securing its margin when the lesion is peripheral and wedge resection is planned

Colon cancer form a colonic graft

Neoplasm of a colonic graft after esophageal reconstruction is rare. We treated a colon cancer patient who developed malignancy in a colonic graft after esophagectomy and reconstruction through a retrosternal route. A male had undergone esophagectomy in his 50s due to a benign esophago-bronchial fistula. His dysphagia became exacerbated 20 years later, and further examinations showed a circumferential tumor on the esophago-colonic anastomosis. He underwent resection of the colonic graft adenocarcinoma with median sternotomy after neoadjuvant chemotherapy. Gastric tube reconstruction was performed through a retrosternal route. This report should be informative in terms of making decisions from an initial reconstruction to follow-up and choosing a therapeutic strategy for colonic graft cancer in the future

Hypervascularized bronchial arteries affect lung cancer surgery

Background: The present study investigated whether highly vascularized bronchial arteries affect the intraoperative blood loss and the operative time of video-assisted thoracic surgery (VATS) lobectomy for patients with non-small cell lung cancer. Methods: We retrospectively collected data on consecutive pathological stage I to IIIA non-small cell lung cancer patients who underwent VATS lobectomy with systematic lymph node dissection between January 2017 and December 2019. Patients were divided into the following two groups according to bronchial artery diameters on preoperative enhanced contrast computed tomography (CT) findings: ≤2 and >2 mm groups. Results: Among the 175 patients enrolled, risk factors for intraoperative blood loss >50 mL were being male (P=0.005), a history of smoking (P=0.01), percent forced expiratory volume in 1 s (FEV1.0%) 2.0 mm (P2.0 mm (P200 min were being male (P2.0 mm (P2.0 mm (P=0.024), and experience of surgeon <10 years (P=0.047) in the multivariable analysis. Conclusions: Bronchial artery diameter was the most important risk factor of intraoperative bleeding and prolonged operative time during VATS lobectomy

マウスiPS細胞由来の気管支肺胞幹細胞は末梢気道上皮再生を促進する

Background: Bronchioalveolar stem cells (BASCs) located at the bronchioalveolar-duct junction (BADJ) are stem cells residing in alveoli and terminal bronchioles that can self-renew and differentiate into alveolar type (AT)-1 cells, AT-2 cells, club cells, and ciliated cells. Following terminal-bronchiole injury, BASCs increase in number and promote repair. However, whether BASCs can be differentiated from mouse-induced pluripotent stem cells (iPSCs) remains unreported, and the therapeutic potential of such cells is unclear. We therefore sought to differentiate BASCs from iPSCs and examine their potential for use in the treatment of epithelial injury in terminal bronchioles. Methods: BASCs were induced using a modified protocol for differentiating mouse iPSCs into AT-2 cells. Differentiated iPSCs were intratracheally transplanted into naphthalene-treated mice. The engraftment of BASCs into the BADJ and their subsequent ability to promote repair of injury to the airway epithelium were evaluated. Results: Flow cytometric analysis revealed that BASCs represented ~ 7% of the cells obtained. Additionally, ultrastructural analysis of these iPSC-derived BASCs via transmission electron microscopy showed that the cells containing secretory granules harboured microvilli, as well as small and immature lamellar body-like structures. When the differentiated iPSCs were intratracheally transplanted in naphthalene-induced airway epithelium injury, transplanted BASCs were found to be engrafted in the BADJ epithelium and alveolar spaces for 14 days after transplantation and to maintain the BASC phenotype. Notably, repair of the terminal-bronchiole epithelium was markedly promoted after transplantation of the differentiated iPSCs. Conclusions: Mouse iPSCs could be differentiated in vitro into cells that display a similar phenotype to BASCs. Given that the differentiated iPSCs promoted epithelial repair in the mouse model of naphthalene-induced airway epithelium injury, this method may serve as a basis for the development of treatments for terminal-bronchiole/alveolar-region disorders

CLE for visceral pleural invasion

Background: Visceral pleural invasion (VPI) in lung cancer is a significant prognostic factor; however, it is difficult to diagnose preoperatively or intraoperatively. In this study, we examined the possibility of intraoperative diagnosis of VPI using confocal laser endomicroscopy (CLE). Methods: Among patients with primary lung cancer who underwent surgery between April 2018 and August 2019, those in whom the tumor was in contact with the pleura on chest computed tomography and whose pleural changes were intraoperatively confirmed were enrolled in this study. In the 35 patients who underwent lung resection (6 cases with visceral pleural infiltration), the area where pleural change was noted was observed and a short video was recorded using CLE. Based on the video images, three evaluators determined the defect ratio (0%, 25%, 50%, 75%, and 100%) of the autofluorescence-positive structure. The area under the receiver operating characteristic curve was used to evaluate the diagnostic performance for VPI. In 15 cases (3 cases with VPI), a validation study was performed for intraoperative VPI according to the cutoff value of the defect ratio of the autofluorescence-positive structure. Results: The areas under the receiver operating characteristic curve for the defect ratio of the autofluorescence-positive structure were 0.86–0.91 for the three readers. Using defect ratio of autofluorescence-positive structure cutoff of ≥50% as predictor of VPI, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 83.3–100.0%, 57.7–73.1%, 35.3–41.7%, 95.0–100.0%, and 75.0–78.1%, respectively, for the three readers. In the validation study, the sensitivity was 100%, the specificity was 83.3%, and the diagnostic accuracy rate was 86.7%. Conclusions: The diagnosis of VPI through CLE is simple, non-invasive, and has high diagnostic accuracy rates. This method may be applicable for determining surgical procedures

A novel efficient feeder-free culture system for the derivation of human induced pluripotent stem cells

Nakagawa, M.et al. A novel efficient feeder-free culture system forthe derivation of human induced pluripotent stem cells.Sci. Rep.4, 3594; DOI:10.1038/srep03594 (2014)

ハッショウ ヨソク ガ コンナン デアッタ ハイガン ジュツゴ カンシツセイ ハイエン キュウセイ ゾウアク ノ 2レイ

Acute exacerbation of interstitial pneumonia （IP） is one of the most severe and fatal postoperative complications in lung cancer patients underlying IP. We treated two patients suffered from acute exacerbation of IP after pulmonary resection for lung cancer. We analyzed their clinical findings. Thoracoscopic lobectomy with mediastinal lymph node dissection was performed in these cases. The patients were diagnosed with acute exacerbation ４ or ５ days after operation and treated with steroids. Both patients had not been diagnosed as IPs before surgery, however, IPs were diagnosed by retrospective analysis of pathological examination for the removal lungs. Chest CT before surgery showed an interstitial shadow in the lung field faintly in these cases. It should be considered that patients who show a faint interstitial shadow in chest CT could potentially cause an acute exacerbation of IP after lung cancer operation