Masanori Shimomura

Drug resistance to paclitaxel is not only associated with ABCB1 mRNA expression but also with drug accumulation in intracellular compartments in human lung cancer cell lines.

In order to clarify the mechanisms of resistance to paclitaxel in lung cancer, three human lung cancer cell lines which exhibit different sensitivity to paclitaxel were investigated from the following viewpoints: overexpression of ATP-binding cassette, sub-family B, member 1 (ABCB1), mutations on paclitaxel binding site of β-tubulin genes, quantity of polymerized tubulin and the intracellular localization of paclitaxel. ABCB1 expression was evaluated by real-time RT-PCR. No correlations were noted between the ABCB1 expression in the sensitive and resistant cell lines at the mRNA level. No mutations on the paclitaxel binding site of the β-tubulin genes were detected in either the resistant or sensitive cells. Live cell images obtained by confocal laser microscopy revealed that the resistant cell line, RERF-LC-KJ, had more accumulation of Oregon Green® 488 conjugated paclitaxel in the lysosomal and extra-lysosomal compartments of cytoplasm than other cell lines. The results obtained in this study indicated that the changes in the subcellular localization could contribute to the production of paclitaxel resistance in lung cancer cell lines. Further studies should be conducted to elucidate the molecular mechanisms that differentiate the intracellular localization of paclitaxel.

Intuitive Touch Panel Navigation System through Kyoto Digital Sosui Network

We have developed multi-touch panel robotic arm control system for thoracoscopic surgery. Our multi-touch panel navigation system consists of green laser guide maker, robotic arms with four spindles, multi-touch panel monitor, and PCs for control regulation. The multi-touch panel monitor recognized the finger-touch; thereby the tip of the robot arm is controlled just on the green maker. For estimation in remote control use, the PC for the robot control was placed in Kyoto Prefectural University of Medicine, which was connected through the Kyoto Digital Sosui Network, a gigabit Ethernet with layer-2 security. Another computer for the remote control of the PC for the robot control was placed in Yamashiro Public Hospital, 35 kilometers south of Kyoto city, through the same gigabit Ethernet. Using virtual network computing (VNC), which is a graphical desktop sharing system to control another computer, we demonstrated a remote control of the robot and collected the packets to examine the traffic bandwidth. The robot was successfully controlled in remote conditions. The throughput of the Ethernet was 16.4 ±3.6 Mbps in the remote control of the robot using VNC. The round-trip time was 19.9 ± 0.39 msec, while 8000 bytes data was sent by using ping command. We demonstrated an intuitive touch panel navigation system, which a surgical robot stopped an arterial bleeding in an animal model. The robot system was successfully controlled through a gigabit Ethernet between two distant hospitals.

Intractable pneumothorax due to rupture of subpleural rheumatoid nodules: a case report

BackgroundIn rare cases, rheumatoid pleural nodules can rupture into the pleural cavity to cause pneumothorax or empyema. We report successful surgical treatment of a patient with an intractable secondary pneumothorax due to rupture of a subpleural rheumatoid nodule into the pleural cavity.Case presentationA 75-year-old man with a medical history of rheumatoid arthritis, acute coronary syndrome, and diabetes was admitted to our hospital because of left chest pain and dyspnea. A chest X-ray and chest computed tomography (CT) scan showed a left pneumothorax and several small subpleural nodules with cavitation. Repeated pleurodesis via a chest tube failed to improve the pneumothorax, so we decided to perform thoracoscopic surgery. Air leakage was detected in the left upper lobe where the subpleural nodule was visible on chest CT. Resection of the lesion successfully resulted in resolution of the air leakage. The final pathological diagnosis of the subpleural nodule was a pulmonary rheumatoid nodule. The patient has had no evidence of recurrence of pneumothorax after surgery.ConclusionsWe obtained a final pathological diagnosis of a rheumatoid nodule that caused an intractable pneumothorax. Pneumothorax associated with rupture of rheumatoid nodules in the subpleural cavitary is difficult to treat with thoracoscopic surgery as a second-line treatment.

Improvements in thoracic surgery outcomes: a multi-institutional collaboration study.

BackgroundTreatment protocols (including those for thoracic surgery) tend to be customized for individual hospitals. Procedural standardization is required to improve surgical tasks and patient outcomes. This study aimed to evaluate the effects of an initiative to standardize surgical tasks for efficient and safe performance.MethodsHospitals associated with the Division of Chest Surgery of the Kyoto Prefectural University of Medicine held joint meetings involving their thoracic surgeons and operating room nurses between February 2011 and November 2012 to standardize surgical tasks. Operation times and blood loss were compared before and after standardization.ResultsThe implementation rate of standardized surgical tasks was 97%. The pre-operative (from entry to the operating room until commencement of surgery) and post-operative (from conclusion of surgery until departure from the operating room) times were significantly decreased after the standardization. When compared according to operative group (all thoracic surgery, lung lobectomy, and partial lung resection), operation times were shorter for all three groups; in addition, the amount of blood loss was lower in all three groups after standardization. A post-standardization survey showed improved morale among the meeting participants.ConclusionsInterdisciplinary standardization of surgical tasks across institutions improved thoracic surgery tasks and surgical outcomes.