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Optical transition properties of nanocrystalline silicon (nc-Si) doped SiO2 thin films prepared by cosputtering with SiO2 target and Si-chips followed by high temperature annealing were investigated as a function of ratio of target area (Si/SiO2) in the range of 0 to 0.19. Optical transmission measurements revealed that the indirect band-gap of nc-Si decreased from 4.87 to 2.32 eV with increasing Si/SiO2 from 0.04 to 0.19, whereas no noticeable absorption was observed for the samples with Si/SiO2 = 0.00. Photoluminescence (PL) measurements showed that considerably weak emissions due to oxygen deficient center (ODC) in SiO2 films were observed at 514-539 nm for samples with lower Si/SiO2 of 0.0-0.09, while the strong emissions due to an interfacial layer between the nc-Si core and the SiO2 surface layer were observed at 746-808 nm for samples with higher Si/SiO2 of 0.13-0.19. PL excitation spectrum monitored at 800 nm showed that the PL at 800 nm was excited through nc-Si. On the other hand, cathodoluminesncence peaks were observed at 455 and 465 nm for the samples with 0.04 and 0.13, respectively, in which both peaks were assigned to originate from oxygen vacancies created during electron beam irradiation. The mechanisms of three types of luminescence, due to the ODC in SiO2, band-to-band transition of nc-Si, and the interfacial layer between the nc-Si core and the SiO2 surface layer, are discussed. [ABSTRACT FROM AUTHOR]

Pneumonia in elderly people is mainly caused by silent aspiration due to an age-related impairment of cough and swallowing reflexes. Because most of the patients with lung cancer are elderly people, we hypothesized that the age-related impairment of these protective reflexes might exist or occur in patients undergoing lung surgery, and cause postoperative pneumonia. We revealed that many elderly patients showed depressed swallowing reflex even before surgery and transient attenuation of cough reflex after surgery, and that postoperative pneumonia occurred only in the patients whose cough and/or swallowing reflex was abnormal postoperatively. Then, we prospectively showed that 30 elderly patients who received perioperative intensive oral care, including professional assessment of oral status, dental cleaning, and patient education for self-oral care by dentists, followed by intensive oral care by intensive care unit nurses, and encouragement of self-oral care by floor nurses, did not develop pneumonia after lung resection. In this study, we retrospectively reviewed the execution status of professional oral care by dentists and the occurrence of postoperative pneumonia in 159 consecutive patients aged 65 or older undergoing lung resection from 2013 to 2014. Thoracic surgeons in our institute asked dentists to provide professional oral care before lung resection only in 30.3% of the subjects in 2013, and 45.8% in 2014. Postoperative pneumonia occurred in 3 out of 76 subjects(3.9%)in 2013, and 1 out of 83(1.2%) in 2014. In 2013, 1 patient who did not receive preoperative professional oral care developed aspiration pneumonia postoperatively followed by acute exacerbation of idiopathic pulmonary fibrosis and in-hospital death. We need to make an effective system to provide preoperative professional oral care by dentists especially for elderly patients and high-risk patients before lung resection.

We report a case of alpha fetoprotein (AFP) -producing lung adenocarcinoma. A 53-year-old man was referred to our hospital due to right pneumothorax. Computed tomography showed right moderate pneumothorax, a solid tumor in the upper lobe (S3) and mediastinal lymph node swelling. The serum AFP level was as high as 223.0 ng/ml. Frozen examination revealed a low-differentiated adenocarcinoma. Based on the pathological and immunohistochemical findings, the tumor was diagnosed as AFP-producing lung adenocarcinoma.

We report a case of intrapulmonary solitary fibrous tumor( SFT). A 34-year-old woman was referred to our hospital due to an abnormal shadow on a chest roentgenogram without symptom. Computed tomography showed a circumscribed intrapulmonary tumor with mild uptake on fluorodeoxyglucose (FDG)-positron emission tomography( PET) in the left lower lobe( S6). Frozen examination revealed a mesenchymal tumor. Based on the pathological and immunohistochemical findings, the tumor was diagnosed as intrapulmonary SFT.

A 68-years-old male patient had been diagnosed as having bronchial carcinoid in B2 and right upper lobectomy with systematic hiler and mediastinal lymphadenectomy had been performed in 1996. Pathological diagnosis was a typical carcinoid (pT1aN0M0, stage I A). In 2004, 4 tumors were found in the trachea, right bronchial stump, right main bronchi and right B6 orfice. These were diagnosed as typical carcinoids by pathology. In 2005 argon plasma coagration was performed.In 2013, a localized recurrence was found in the right S6 by chest computed tomography (CT). The segmentectomy of the right S6 was performed. Even after radical operation for typical carcinoids, we should conduct long-term observation.

A 54-year-old man was referred to our hospital because of an abnormal shadow on chest X-ray. A computed tomography( CT) scan of the chest revealed a 6.5 cm tumor in the right upper lobe suspected of superior vena cava (SVC) infiltration. He was diagnosed as lung cancer(adenocarcinoma), and the right upper lobectomy with partial resection of SVC was performed. But the pathology confirmed the surgery to be non-curative. Nine months after operation, carcinomatous pleuritis was detected on chest X-ray. Since deoxyribonucleic acid (DNA)analysis revealed a mutation of epidermal growth factor receptor (EGFR) gene in exon 21, gefitinib treatment was started. Nine months later, pleural effusion regressed and his cerum carcinoembrionic antigen( CEA) level was normalized. 4 years later, gefitinib was discontinued by patient's request, however, he is alive without any signs of relapse 9 years after the operation.