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1.
Hideyuki Masuda Makoto Kimura Akiko Nishioka Hiroshi Kato Akimichi Morita 《Journal of dermatological science》2019,93(2):109-115
Background
Photosensitizers used for photodynamic therapy (PDT) to treat dermatologic disease are metabolized into mainly protoporphyrin IX (PpIX), which has five absorption wavelength peaks: 410?nm, 510?nm, 545?nm, 580?nm, and 630?nm. Although only red light around 635?nm and blue light around 400?nm are used as light sources for PDT, the efficiency of PDT might be improved by using multiple wavelengths, including those that correspond to the other absorption peaks of PpIX. Furthermore, because the target disease often occurs on the face, a flexible-type light-source unit that can be fitted to the lesion without unnecessarily exposing the mucous membranes, e.g., the eyes, nostrils, and mouth, is preferred.Objective
We investigated the efficacy of a flexible light-emitting diode (LED) unit that emits multiple wavelengths to improve PDT effects.Methods
HaCaT cells were incubated with 5-ALA and subsequently irradiated with either a single wavelength or sequentially with two wavelengths. Cell viability and reactive oxygen species were analyzed. Nude mice were implanted with COLO679 cells by subcutaneous injection into the flank. 5-ALA was subcutaneously injected into the tumor. The tumor was irradiated with 50?J/cm2 (day 0) and assessed daily until day 21.Results
The synergistic PDT effects of dual-wavelength irradiation and reactive oxygen species production were highest with the 405-nm and 505-nm wavelength combination. This dual wavelength combination was also the most effective in vivo.Conclusion
We could therefore conclude that dual-wavelength PDT is an efficient strategy for improving the therapeutic effects of PDT. Using a flexible LED unit is expected to achieve more uniform irradiation of uneven areas. 相似文献2.
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4.
Comparative safety study on severe anemia by simeprevir versus telaprevir‐based triple therapy for chronic hepatitis C
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Eiichi Ogawa Norihiro Furusyo Eiji Kajiwara Hideyuki Nomura Akira Kawano Kazuhiro Takahashi Kazufumi Dohmen Takeaki Satoh Koichi Azuma Makoto Nakamuta Toshimasa Koyanagi Kazuhiro Kotoh Shinji Shimoda Jun Hayashi The Kyushu University Liver Disease Study Group 《Journal of gastroenterology and hepatology》2015,30(8):1309-1316
5.
Intraductal papillary mucinous tumor (IPMT) of the pancreas is characterized by slow growth and a relatively favorable prognosis, however, invasive cancer originating in an IPMT is associated with a poor prognosis. Although various parameters in imaging modalities have been advocated to differentiate between benign IPMN and malignant ones, it is not easy to obtain definite diagnosis based on these parameters. Peroral pancreatoscopy (POPS) allows a clear and direct visualization of the pancreatic duct, providing useful information regarding tumor nature in IPMT. The authors have studied the usefulness of POPS in the diagnosis of IPMT. Nevertheless, its usefulness is not necessarily widely accepted and the significance of POPS is still controversial. In this review, the authors intended to address the diagnostic value of POPS and to clarify its role in the diagnosis of IPMT. The authors think treatment of IPMT can be improved by introducing POPS because the determination of surgical procedure as well as the area of resection based on the preoperative diagnosis of the involvement of the main pancreatic duct and branch duct is inevitable. 相似文献
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7.
Nobuyuki Inoue Kouji Nagaike Shinichi Ishihara Mitsuhiko Nakamura Toshio Kuroshima 《Digestive endoscopy》2006,18(2):134-137
Background: For management of bowel obstruction due to colorectal cancer, endoscopic trans‐anal decompression technique has been first reported by Lelcuk et al. in 1986 using balloon dilatation technique. Since then, various types of trans‐anal decompression tubes have been clinically used for patients suffering from left side obstructing colorectal cancer as an emergent decompressing device. At present, two types of trans‐anal ileus tube (trans‐anal decompression tube) have been available for clinical use, but they have two main problems that are late colon perforations caused by the tip of the tube and tube obstruction by stool. Methods: Analysis on three late colon perforations experienced with the use of conventional devices drew possible improvements to make a trans‐anal ileus tube less harmful. To overcome the pitfalls inherent to conventional tubes, the author has developed an improved trans‐anal ileus tube with a balloon installed at the very end of the tube (‘balloon‐tipped type’) made of silicone, measuring 1200 or 1700 mm in total length and 22 Fr in outer diameter. It has been used for 12 cases with obstructing colorectal cancer etc. and its outcomes were compared with those obtained by the use of conventional trans‐anal ileus tube. Results: No late perforations have been encountered, but tube obstruction did occur in one of 12 cases. Conclusion: The new trans‐anal ileus tube with a balloon installed at the tip of ileus tube is considered to be safer and especially effective in preventing late colon perforation and tube obstruction. 相似文献
8.
H Ishihara M Bjeljac D Straumann Y Kaku P Roth Y Yonekawa 《Minimally invasive neurosurgery》2006,49(3):168-172
OBJECTIVE: A safe entry zone to tegmental lesions was identified based on intraoperative electrophysiological findings, the compound muscle action potentials (CMAP) from the extraocular muscles, and anatomic considerations. This entry zone is bordered caudally by the intramesencephalic path of the trochlear, laterally by the spinothalamic tract, and rostrally by the caudal margin of the brachium of the superior colliculus. METHODS: Four intrinsic midbrain lesions were operated upon via the safe entry zone using the infratentorial paramedian supracerebellar approach. All lesions involved the tegmentum and included an anaplastic astrocytoma, a metastatic brain tumor, a radiation necrosis, and a cavernous angioma. CMAP were bilaterally monitored from the inferior recti (for oculomotor function) and superior oblique (for trochlear nerve function) muscles. RESULTS: In three of four cases, CMAP related to the oculomotor nerve were obtained upon stimulation at the cavity wall after removal of the tumor. Stimulation at the surface of the quadrigeminal plate, however, did not cause any CMAP response. Using this monitoring as an indicator, the lesions were totally removed. CONCLUSIONS: In the surgery of tegmental lesions, CMAP monitoring from extraocular muscles is particularly helpful to prevent damage to crucial neural structures during removal of intrinsic lesions, but less so to select the site of the medullary incision. The approach via the lateral part of the colliculi is considered to be a safe route to approach the tegmental lesions. 相似文献
9.
10.
We investigated the clinical background of patients at Shin-Kokura Hospital who showed a positive culture of pleural effusion
during the period from January 1998 through December 2002. Microorganism cultures of the pleural effusions of 127 patients
were performed in this 5-year period. Seventeen patients showed a positive microorganism culture from a pleural effusion,
and 12 of these patients (70.6%) were 60 years old or more. Ten patients were diagnosed with thoracic empyema. Thirteen patients
had an underlying disease such as malignancy (5 cases), diabetes mellitus (4 cases), etc. A purulent effusion and a high concentration
of lactic dehydrogenase (LDH) in the pleural fluid were more frequently recognized in the positive-culture group. A total
of 21 strains of microorganism were isolated from the 17 patients, including 10 strains of Gram-positive cocci, 6 strains
of Gram-negative bacilli, 3 strains of anaerobes, 1 strain of mycobacterium (Mycobacterium tuberculosis), and 1 strain of fungus. Susceptibility to antimicrobial agents was generally good for most of the microorganisms isolated.
Of the 17 patients, chest-tube drainage was performed in 13, and 6 needed a surgical operation. Twelve patients improved,
but 5 died. In this study, thoracic empyema accounted for 58.8% of the 17 cases with a positive culture of pleural effusion.
Of the 10 thoracic empyema patients, 5 patients needed surgical treatment in spite of adequate antimicrobial treatment and
chest-tube drainage. Our data indicate that thoracic empyema is still difficult to treat, and thus adequate and rapid treatment
is needed for any pleural infection. 相似文献