One-Step Conversion of Glutamic Acid into 2-Pyrrolidone on a Supported Ru Catalyst in a Hydrogen Atmosphere: Remarkable Effect of CO Activation

Glutamic acid, an abundant nonessential amino acid, was converted into 2-pyrrolidone in the presence of a supported Ru catalyst under a pressurized hydrogen atmosphere. This reaction pathway proceeded through the dehydration of glutamic acid into pyroglutamic acid, subsequent hydrogenation, and the dehydrogenation–decarbonylation of pyroglutaminol into 2-pyrrolidone. In the conversion of pyroglutaminol, Ru/Al2O3 exhibited notably higher activity than supported Pt, Pd, and Rh catalysts. IR analysis revealed that Ru can hydrogenate the formed CO through dehydrogenation–decarbonylation of hydroxymethyl groups in pyroglutaminol and can also easily desorb CH4 from the active sites on Ru. Furthermore, Ru/Al2O3 showed the highest catalytic activity among the tested catalysts in the conversion of pyroglutamic acid. Consequently, the conversion of glutamic acid produced a high yield of 2-pyrrolidone by using the supported Ru catalyst. This is the first report of this one-pot reaction under mild reaction conditions (433 K, 2 MPa H2)„ which avoids the degradation of unstable amino acids above 473 K

Transoral surgery for superficial head and neck cancer: National Multi‐Center Survey in Japan

Head and neck cancers, especially in hypopharynx and oropharynx, are often detected at advanced stage with poor prognosis. Narrow band imaging enables detection of superficial cancers and transoral surgery is performed with curative intent. However, pathological evaluation and real-world safety and clinical outcomes have not been clearly understood. The aim of this nationwide multicenter study was to investigate the safety and efficacy of transoral surgery for superficial head and neck cancer. We collected the patients with superficial head and neck squamous cell carcinoma who were treated by transoral surgery from 27 hospitals in Japan. Central pathology review was undertaken on all of the resected specimens. The primary objective was effectiveness of transoral surgery, and the secondary objective was safety including incidence and severity of adverse events. Among the 568 patients, a total of 662 lesions were primarily treated by 575 sessions of transoral surgery. The median tumor diameter was 12 mm (range 1–75) endoscopically. Among the lesions, 57.4% were diagnosed as squamous cell carcinoma in situ. The median procedure time was 48 minutes (range 2–357). Adverse events occurred in 12.7%. Life-threatening complications occurred in 0.5%, but there were no treatment-related deaths. During a median follow-up period of 46.1 months (range 1–113), the 3-year overall survival rate, relapse-free survival rate, cause-specific survival rate, and larynx-preservation survival rate were 88.1%, 84.4%, 99.6%, and 87.5%, respectively. Transoral surgery for superficial head and neck cancer offers effective minimally invasive treatment

Cochlear implantation in an adult patient with auditory neuropathy

The original publication is available at www.springerlink.com. authorWe present a case report of effective cochlear implantation for an adult patient with auditory neuropathy. A 34-year-old man developed bilateral hearing loss at approximately 10 years of age. His speech discrimination score was very severe despite only moderate sensorineural hearing loss. Absence of auditory brainstem responses (ABR) and preservation of distortion product otoacoustic emissions (DPOAE) were confirmed by our audiological examinations. After cochlear implantation, good responses for electrically evoked compound action potential (EAP) and electrically evoked ABR (EABR) were observed. Postoperatively, his audiological performance was significantly improved. We conclude that cochlear implantation can be a valid option for patients with auditory neuropathy

その基礎と臨床 声帯麻痺治療に対する機能的電気刺激の応用

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