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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.
3.
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
4.
5.
Peter Chiba Barbara Tell Walter Jger Elisabeth Richter Manuela Hitzlera Gerhard Ecker 《Archiv der Pharmazie》1997,330(11):343-347
A series of 5-hydroxy and 5-benzyloxy analogs of the antiarrhythmic and multidrug resistance (MDR) modulating drug propafenone was synthesized and the MDR-modulating activity of the compounds was evaluated using a daunomycin efflux assay system. The key step of the synthesis is the selective reduction of the double bond in 1 without cleavage of the benzyl group thus leading to the phenol 3 . Alkylation with epichlorohydrine followed by nucleophilic epoxide ring opening gave the benzylated target compounds 5a–d . Subsequent cleavage of the benzyl group gave the 5-hydroxy analogs 6a–d . Structure activity relationship studies showed, that the 5-hydroxy derivates 6a–d fit the log P/log potency correlation line previously established for a series of propafenone analogs. In contrast, all four 5-benzyloxy analogs 5a–d showed almost identical EC50 values, independent of their log P value. 相似文献
6.
Surgical treatment of congenital dilatation of the bile duct with special reference to late complications after total excisional operation 总被引:3,自引:0,他引:3
R Ohi S Yaoita T Kamiyama M Ibrahim Y Hayashi T Chiba 《Journal of pediatric surgery》1990,25(6):613-617
The surgical treatment of 100 cases with congenital dilatation of bile duct with special reference to late complications was analyzed. There were no deaths nor occurrences of malignancy. Among 91 patients who had undergone the standard operation, namely total excision of the dilated extrahepatic bile duct and reconstruction after Roux-en-Y hepaticojejunostomy, there were one early complication (pancreatic juice leakage) and five late complications (four intrahepatic gallstones and one liver abscess). The cause of intrahepatic gallstone formation after a total excisional operation was attributed to the remaining intrahepatic bile duct dilatation and the stenosis located between the intrahepatic bile duct dilatation and the common hepatic duct. Accordingly, these results support the total excisional procedure for this condition; however, with regard to the cases associated with cystic dilatation of intrahepatic bile ducts, completely free bile drainage from the dilated intrahepatic biliary system should be performed at the radical operation. 相似文献
7.
Acute Immobilization Stress and Intraventricular Injection of CRF Suppress Naloxone-Induced LH Release in Ovariectomized Estrogen-Primed Rats 总被引:1,自引:0,他引:1
Tatsuo Akema Atsuhiko Chiba Reiji Shinozaki Morihiro Oshida Fukuko Kimura & Jun-ichi Toyoda 《Journal of neuroendocrinology》1996,8(8):647-652
The present study was undertaken to evaluate the role and possible interaction of the endogenous opioid peptide (EOP) and corticotropin-releasing factor (CRF) in the acute stress-induced suppression of gonadotropin secretion in ovariectomized estrogen-primed rats. An intravenous (i.v.) injection of naloxone (10 or 20 mg/kg), an EOP antagonist, significantly elevated serum luteinizing hormone (LH) levels within 10 min in non-stressed animals. The naloxone-induced LH release was completely eliminated when tested 30 min after the onset of acute immobilization. In a subsequent study, it was found that suppression of the naloxone-induced LH release occurred as early as 5 min after the stress onset, and was still evident 60 min after the end of a 30-min period of immobilization. The effect of naloxone was restored 3 h after liberation of the animal from the 30-min immobilization. An intraventricular (i.c.v.) injection of CRF (1 or 5 μg) also significantly suppressed, in a dose-related manner, the effect of a subsequent i.v. injection of naloxone. However, an i.c.v. injection of α -helical CRF(9-41) (25 or 50 μg), a CRF antagonist, prior to immobilization, could not interfere with the suppressive effect of stress on naloxone-induced LH release. These results suggest that both acute immobilization stress and CRF can inhibit the LH secretory activity without mediation by EOP neurons. However, the stress-related suppression may involve non-CRF mechanism(s). 相似文献
8.
9.
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
10.