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Mi Young Jung Jae Hyoung Lee Cho Rok Kim Hyun Je Kim Won Jung Koh Chang Suk Ki Joo Heung Lee Jun Mo Yang Dong Youn Lee 《ANNALS OF DERMATOLOGY》2014,26(1):92-95
Mycobacterium massiliense which is recognized as a separate species from M. abscessus is little known regarding its clinical patterns and the response to treatment. We present a case of a localized cutaneous infection due to M. massiliense of the sole associated with acupuncture. M. massiliense was identified via polymerase chain reaction-hybridization analysis. We treated the patient with single-drug therapy consisting of clarithromycin for 4 months and the patient showed a significant response to this treatment. 相似文献
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Yeong Byeon Hyoung Yool Lee Kyungjin Lee Kyoungwhan Back 《Journal of pineal research》2014,57(2):147-154
Ectopic overexpression of melatonin biosynthetic genes of animal origin has been used to generate melatonin‐rich transgenic plants to examine the functional roles of melatonin in plants. However, the subcellular localization of these proteins expressed in the transgenic plants remains unknown. We studied the localization of sheep (Ovis aries) serotonin N‐acetyltransferase (OaSNAT) and a translational fusion of a rice SNAT transit peptide to OaSNAT (TS:OaSNAT) in plants. Laser confocal microscopy analysis revealed that both OaSNAT and TS:OaSNAT proteins were localized to the cytoplasm even with the addition of the transit sequence to OaSNAT. Transgenic rice plants overexpressing the TS:OaSNAT fusion transgene exhibited high SNAT enzyme activity relative to untransformed wild‐type plants, but lower activity than transgenic rice plants expressing the wild‐type OaSNAT gene. Melatonin levels in both types of transgenic rice plant corresponded well with SNAT enzyme activity levels. The TS:OaSNAT transgenic lines exhibited increased seminal root growth relative to wild‐type plants, but less than in the OaSNAT transgenic lines, confirming that melatonin promotes root growth. Seed‐specific OaSNAT expression under the control of a rice prolamin promoter did not confer high levels of melatonin production in transgenic rice seeds compared with seeds from transgenic plants expressing OaSNAT under the control of the constitutive maize ubiquitin promoter. 相似文献
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Yeong Byeon Sangkyu Park Hyoung Yool Lee Young‐Soon Kim Kyoungwhan Back 《Journal of pineal research》2014,56(3):275-282
A major goal of plant biotechnology is to improve the nutritional qualities of crop plants through metabolic engineering. Melatonin is a well‐known bioactive molecule with an array of health‐promoting properties, including potent antioxidant capability. To generate melatonin‐rich rice plants, we first independently overexpressed three tryptophan decarboxylase isogenes in the rice genome. Melatonin levels were altered in the transgenic lines through overexpression of TDC1, TDC2, and TDC3; TDC3 transgenic seed (TDC3‐1) had melatonin concentrations 31‐fold higher than those of wild‐type seeds. In TDC3 transgenic seedlings, however, only a doubling of melatonin content occurred over wild‐type levels. Thus, a seed‐specific accumulation of melatonin appears to occur in TDC3 transgenic lines. In addition to increased melatonin content, TDC3 transgenic lines also had enhanced levels of melatonin intermediates including 5‐hydroxytryptophan, tryptamine, serotonin, and N‐acetylserotonin. In contrast, expression levels of melatonin biosynthetic mRNA did not increase in TDC3 transgenic lines, indicating that increases in melatonin and its intermediates in these lines are attributable exclusively to overexpression of the TDC3 gene. 相似文献
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Chloroplast overexpression of rice caffeic acid O‐methyltransferase increases melatonin production in chloroplasts via the 5‐methoxytryptamine pathway in transgenic rice plants
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Recent analyses of the enzymatic features of various melatonin biosynthetic genes from bacteria, animals, and plants have led to the hypothesis that melatonin could be synthesized via the 5‐methoxytryptamine (5‐MT) pathway. 5‐MT is known to be synthesized in vitro from serotonin by the enzymatic action of O‐methyltransferases, including N‐acetylserotonin methyltransferase (ASMT) and caffeic acid O‐methyltransferase (COMT), leading to melatonin synthesis by the subsequent enzymatic reaction with serotonin N‐acetyltransferase (SNAT). Here, we show that 5‐MT was produced and served as a precursor for melatonin synthesis in plants. When rice seedlings were challenged with senescence treatment, 5‐MT levels and melatonin production were increased in transgenic rice seedlings overexpressing the rice COMT in chloroplasts, while no such increases were observed in wild‐type or transgenic seedlings overexpressing the rice COMT in the cytosol, suggesting a 5‐MT transport limitation from the cytosol to chloroplasts. In contrast, cadmium treatment led to results different from those in senescence. The enhanced melatonin production was not observed in the chloroplast COMT lines relative over the cytosol COMT lines although 5‐MT levels were equally induced in all genotypes upon cadmium treatment. The transgenic seedlings with enhanced melatonin in their chloroplasts exhibited improved seedling growth vs the wild type under continuous light conditions. This is the first report describing enhanced melatonin production in chloroplasts via the 5‐MT pathway with the ectopic overexpression of COMT in chloroplasts in plants. 相似文献
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Won Joong Jeon Hee Bok Chae Seon Mee Park Sei Jin Youn Jae Woon Choi Seok Hyoung Kim 《Taehan Sohwagi Hakhoe chi》2006,48(6):438-442
Small cell carcinoma is usually seen in the lung, but rarely involves the gastrointestinal tract including biliary tract. A 65 year-old man was admitted because of obstructive jaundice. A smooth-surfaced round intraluminal mass with proximal bile duct dilatation was seen in the proximal common bile duct on endoscopic retrograde cholangiogram. Under the diagnosis of bile duct cancer, pylorus-preserving pancreatoduodenectomy was done. Pathology revealed a 2 cm sized small cell carcinoma in the proximal common bile duct and distal common hepatic duct. On immunohistochemical stain, the tumor cells were positive for neuroendocrine markers CD56 and synaptophysin. After surgery, the patient received 5 cycles of adjuvant chemotherapy with VIP (etoposide, ifosfamide, and cisplatin) regimen. However, the patient died of liver metastasis 12 months after the diagnosis. We report a case of extrapulmonary small cell carcinoma arising from the common bile duct. 相似文献