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51.
Woo Jung Kim Young Ok Kim Jin Hee Kim Bo-Hye Nam Dong-Gyun Kim Cheul Min An Jun Sik Lee Pan Soo Kim Hye Min Lee Joa-Sup Oh Jong Suk Lee 《Marine drugs》2016,14(1)
The ocean is a rich resource of flora, fauna, and food. A wild-type bacterial strain showing confluent growth on marine agar with antibacterial activity was isolated from marine water, identified using 16S rDNA sequence analysis as Pseudoalteromonas sp., and designated as strain M2. This strain was found to produce various secondary metabolites including quinolone alkaloids. Using high-resolution mass spectrometry (MS) and nuclear magnetic resonance (NMR) analysis, we identified nine secondary metabolites of 4-hydroxy-2-alkylquinoline (pseudane-III, IV, V, VI, VII, VIII, IX, X, and XI). Additionally, this strain produced two novel, closely related compounds, 2-isopentylqunoline-4-one and 2-(2,3-dimetylbutyl)qunoline-4-(1H)-one, which have not been previously reported from marine bacteria. From the metabolites produced by Pseudoalteromonas sp. M2, 2-(2,3-dimethylbutyl)quinolin-4-one, pseudane-VI, and pseudane-VII inhibited melanin synthesis in Melan-A cells by 23.0%, 28.2%, and 42.7%, respectively, wherein pseudane-VII showed the highest inhibition at 8 µg/mL. The results of this study suggest that liquid chromatography (LC)-MS/MS-based metabolite screening effectively improves the efficiency of novel metabolite discovery. Additionally, these compounds are promising candidates for further bioactivity development. 相似文献
52.
Hyunjun Woo Min-Kyung Kim Sohyeon Park Seung-Hee Han Hyeon-Cheol Shin Byeong-gon Kim Seung-Ha Oh Myung-Whan Suh Jun-Ho Lee Moo-Kyun Park 《Marine drugs》2021,19(8)
One of the well-known causes of hearing loss is noise. Approximately 31.1% of Americans between the ages of 20 and 69 years (61.1 million people) have high-frequency hearing loss associated with noise exposure. In addition, recurrent noise exposure can accelerate age-related hearing loss. Phlorofucofuroeckol A (PFF-A) and dieckol, polyphenols extracted from the brown alga Ecklonia cava, are potent antioxidant agents. In this study, we investigated the effect of PFF-A and dieckol on the consequences of noise exposure in mice. In 1,1-diphenyl-2-picrylhydrazyl assay, dieckol and PFF-A both showed significant radical-scavenging activity. The mice were exposed to 115 dB SPL of noise one single time for 2 h. Auditory brainstem response(ABR) threshold shifts 4 h after 4 kHz noise exposure in mice that received dieckol were significantly lower than those in the saline with noise group. The high-PFF-A group showed a lower threshold shift at click and 16 kHz 1 day after noise exposure than the control group. The high-PFF-A group also showed higher hair cell survival than in the control at 3 days after exposure in the apical turn. These results suggest that noise-induced hair cell damage in cochlear and the ABR threshold shift can be alleviated by dieckol and PFF-A in the mouse. Derivatives of these compounds may be applied to individuals who are inevitably exposed to noise, contributing to the prevention of noise-induced hearing loss with a low probability of adverse effects. 相似文献
53.
Hak Jin Kim Yong Woo Kim In Sook Lee Jong Woon Song Yeon Joo Jeong Seon Hee Choi Kyung Un Choi Kuen Tak Suh Byung Mann Cho 《Acta veterinaria Scandinavica》2009,51(1):30
Background
To test the hypothesis that triolein emulsion will increase vascular permeability of skeletal muscle.Methods
Triolein emulsion was infused into the superficial femoral artery in rabbits (triolein group, n = 12). As a control, saline was infused (saline group, n = 18). Pre- and post-contrast T1-weighted MR images were obtained two hours after infusion. The MR images were qualitatively and quantitatively evaluated by assessing the contrast enhancement of the ipsilateral muscles. Histologic examination was performed in all rabbits.Results
The ipsilateral muscles of the rabbits in the triolein group showed contrast enhancement, as opposed to in the ipsilateral muscles of the rabbits in the saline group. The contrast enhancement of the lesions was statistically significant (p < 0.001). Histologic findings showed that most examination areas of the triolein and saline groups had a normal appearance.Conclusion
Rabbit thigh muscle revealed significantly increased vascular permeability with triolein emulsion; this was clearly demonstrated on the postcontrast MR images. 相似文献54.
55.
Jae-Won Byun Soon-Seek Yoon Gye-Hyeong Woo Byeong Yeal Jung Yi-Seok Joo 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(3):269-271
An outbreak of fatal hemorrhagic pneumonia with 70~90% morbidity and 50% mortality occurred in an animal shelter in Yangju, Gyeonggi Province, Korea. Clinically, the affected dogs showed severe respiratory distress within 48 h after arriving in the shelter. The dead were found mainly with nasal bleeding and hematemesis. At necropsy, hemothorax and hemorrhagic pneumonia along with severe pulmonary consolidation was observed, though histopathological analysis showed mainly hemorrhagic bronchopneumonia. Lymphoid depletion was inconsistently seen in the spleen, tonsil and bronchial lymph node. Gram-positive colonies were shown in blood vessels or parenchyma of cerebrum, lung, liver, spleen, and kidney. Also, Streptococcus (S.) equi subsp. zooepidemicus was isolated from the various organs in which the bacterium was microscopically and histologically detected. In addition, approximately 0.9 Kb specific amplicon, antiphagocytic factor H binding protein, was amplified in the bacterial isolates. In this study, we reported an outbreak of canine hemorrhagic bronchopneumonia caused by S. equi subsp. zooepidemicus in an animal shelter in Yangju, Korea. 相似文献
56.
Dae Sub Song Youn Jeong Lee Ok Mi Jeong Yong Joo Kim Chan Hee Park Jung Eun Yoo Woo Jin Jeon Jun Hun Kwon Gun Woo Ha Bo Kyu Kang Chul Seung Lee Hye Kwon Kim Byeong Yeal Jung Jae Hong Kim Jin Sik Oh 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(4):323-329
Active serologic surveillance is necessary to control the spread of the avian influenza virus (AIV). In this study, we evaluated a commercially-available cELISA in terms of its ability to detect AIV antibodies in the sera of 3,358 animals from twelve species. cELISA detected antibodies against reference H1- through H15-subtype AIV strains without cross reactivity. Furthermore, the cELISA was able to detect antibodies produced following a challenge of the AIV H9N2 subtype in chickens, or following vaccination of the AIV H9 or H5 subtypes in chickens, ducks and geese. Next, we tested the sensitivity and specificity of the cELISA with sera from twelve different animal species, and compared these results with those obtained by the hemagglutination-inhibition (HI) test, the "gold standard" in AIV sera surveillance, a second commercially-available cELISA (IZS ELISA), or the agar gel precipitation (AGP) test. Compared with the HI test, the sensitivities and specificities of cELISA were 95% and 96% in chicken, 86% and 88% in duck, 97% and 100% in turkey, 100% and 87% in goose, and 91% and 97% in swine, respectively. The sensitivities and specificities of the cELISA in this study were higher than those of IZS ELISA for the duck, turkey, goose, and grey partridge sera samples. The results of AGP test against duck and turkey sera also showed significant correlation with the results of cELISA (R-value >0.9). In terms of flock sensitivity, the cELISA correlated better with the HI test than with commercially-available indirect ELISAs, with 100% flock sensitivity. 相似文献
57.
58.
Yong Hoon Lee Seungdon Lee Dong Hee Lee Sang Hye Ji Hyun Young Chang Sunggi Heu Jae Wook Hyun Dong-Soo Ra Eun Woo Park 《European journal of plant pathology / European Foundation for Plant Pathology》2008,120(1):97-102
Soil-borne cereal mosaic virus (SBCMV) causes a severe disease in susceptible cultivars of winter wheat. The virus is vectored by the soil-borne protist
Polymyxa graminis. Experiments were conducted to investigate whether SBCMV RNA2 could persist in seed from SBCMV-infected susceptible cultivars
of winter wheat. Over 7,000 seedlings were generated from seed collected from two cultivars of SBCMV-infected winter wheat.
Seedlings were grown in a glasshouse compartment and batch tested for the presence of SBCMV using real-time RT-PCR. The majority
of batches tested positive for SBCMV, indicating an RNA2 transmission rate of 1.8–9.4% in wheat. The presence of the virus
was confirmed by amplifying and sequencing a larger (400 bp) fragment of viral RNA2 in a sub-set of the seedlings testing
positive by real-time RT-PCR. Root extracts from this sub-set tested negative for P. graminis using real-time PCR. The implications for disease epidemiology of this virus are discussed.
The authors are British Civil Servants and as such their work is subject to British Crown Copyright. This means the exclusive
copyright for the article cannot be transferred. 相似文献
59.
60.
In Brassicaceae crop breeding programs, wild relatives have been evaluated as genetic resources to develop new cultivars with biotic and abiotic stress resistance. This has become necessary because of the diversification of ecotypes of diseases and pests, changing food preferences, advances in production technology, the use of new approaches such as in vitro breeding programs, and the need for economical production of F1 seed. To produce potential new cultivars, interspecific and intergeneric hybridizations have been performed between cultivated species and between cultivated species and their wild relatives. Furthermore, interspecific and intergeneric hybrids have been successfully produced using embryo rescue techniques. In this paper, we review the interspecific and intergeneric incompatibilities between Brassicaceae crops and their wild relatives, and the production, characterization, and improvement of synthetic amphidiploid lines, alien gene introgression lines, alloplasmic lines, monosomic alien chromosome addition lines, and monosomic alien chromosome substitution lines. The goal is to provide useful materials to support practical breeding strategies and to study the genetic effects of individual chromosomes on plant traits, the number of genes that control a trait, their linkage relationships, and genetic improvement in Brassicaceae crops. 相似文献