Spatiotemporal Control of Ice Crystallization in Supercooled Water via an Ultrashort Laser Impulse.

Focused irradiation with ultrashort laser pulses realized the fine spatiotemporal control of ice crystallization in supercooled water. An effective multiphoton excitation at the laser focus generated shockwaves and bubbles, which acted as an impulse for inducing ice crystal nucleation. The impulse that was localized close to the laser focus and accompanied by a small temperature elevation allowed the precise position control of ice crystallization and its observation with spatiotemporal resolution of micrometers and microseconds using a microscope. To verify the versatility of this laser method, we also applied it using various aqueous systems (e.g., plant extracts). The systematic study of crystallization probability revealed that laser-induced cavitation bubbles play a crucial role in inducing ice crystal nucleation. This method can be used as a tool for studying ice crystallization dynamics in various natural and biological phenomena.

Risk Factors for Postoperative Bleeding in Endoscopic Submucosal Dissection of Colorectal Tumors.

BACKGROUND: Colonoscopic removal of adenomatous polyps or early cancer prevents death from colorectal cancer. Endoscopic submucosal dissection (ESD), which enables endoscopists to perform en bloc resection of flat or depressed colorectal tumors >20 mm, has recently been introduced and become a standard procedure in Japan. Although postoperative bleeding (POB) is a major complication associated with ESD, risk factors for POB have not been fully identified. METHODS: A total of 451 patients (509 lesions) who underwent colorectal ESD were retrospectively analyzed to identify clinical parameters associated with POB. RESULTS: POB occurred in 14 patients, and 7 of them had received antithrombotic therapy before ESD. Uni- and multivariate analyses revealed that antithrombotic therapy and rectal tumor location were strongly associated with POB following colorectal ESD. The incidence of POB was higher in patients on heparin bridge therapy (HBT) for the replacement of antithrombotic therapy than in patients with no HBT. Four of 7 patients (57.1%) on antithrombotic therapy experienced POB from the rectal lesions. CONCLUSION: Antithrombotic therapy and rectal lesions result in a higher POB incidence after colorectal ESD.

[Laryngeal Atypical Carcinoid Combined with Squamous Cell Carcinoma: A Case Report].

The primary laryngeal atypical carcinoid is relatively rare, and the tumor combined with other histologic types including squamous cell carcinoma is extremely rare. We experienced a case which was complicated with atypical carcinoid and squamous cell carcinoma. A 79 years old man complaining of sputum was admitted to Hiroshima City Hospital. A tumor was seen in over the right glottis and the right vocal fold was fixed. Squamous cell carcinoma was diagnosed based on a biopsy harvested under laryngoscopy. Imaging studies (CT, MRI) were done. The primary tumor was in the right aryepiglottic fold, and one swollen lymph node was found in level 2 (right side). Based on the findings, the stage was T3N1M0. We performed a total laryngectomy and right neck dissection. Atypical carcinoid and squamous cell carcinoma were detected in the same tumor. There were two lymph node metastases, both of which were atypical carcinoid metastases. Postoperative irradiation was provided. It is now 4 years since the operation, but the patient lives without relapse and metastasis of this disease.