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1.
Eun Jin Park Joon Young Song Min Ju Choi Ji Ho Jeon Jah-yeon Choi Tae Un Yang Kyung Wook Hong Ji Yun Noh Hee Jin Cheong Woo Joo Kim 《The Korean journal of parasitology》2014,52(4):425-428
A 45-year-old-male who had underlying ulcerative colitis and presented with fever and dry cough. Initially, the patient was considered to have invasive aspergillosis due to a positive galactomannan assay. He was treated with amphotericin B followed by voriconazole. Nevertheless, the patient deteriorated clinically and radiographically. The lung biopsy revealed eosinophilic pneumonia, and ELISA for Toxocara antigen was positive, leading to a diagnosis of pulmonary toxocariasis. After a 10-day treatment course with albendazole and adjunctive steroids, the patient recovered completely without any sequelae. Pulmonary toxocariasis may be considered in patients with subacute or chronic pneumonia unresponsive to antibiotic agents, particularly in cases with eosinophilia. 相似文献
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Ha Na Seo Bo Young Jeon Hung Thuan Tran Dae Hee Ahn Doo Hyun Park 《Biotechnology and Bioprocess Engineering》2008,13(2):224-231
Saccharomyces sp. SK0704 (further defined as SK0704) isolated from long-term-ripening kimchi was identified by a biochemical method with
an API kit; its physiology was found to be very similar to that of S. cerevisiae ATCC 26603 (further defined as ATCC 26603), except in terms of starch utilization. SK0704 did not excrete extracellular glucoamylase,
but utilized starch as a sole carbon source under only aerobic conditions. Crude enzyme excreted from SK0704 catalyzed the
saccharification of starch to glucose, but ATCC 26603 did not. The PCR product obtained using the chromosomal DNA of SK0704
and the primers designed on the basis of the extracellular glucoamylase-coding gene of S. diastaticus was homologous with the intracellular sporulation-specific glucoamylase of S. cerevisiae. SDS-PAGE pattern of soluble protein extracted from yeast cells grown on glucose was greatly different from that on starch.
From these results, we proposed that the SK0704 may have a specific physiological function for starch catabolism such as membrane
transport system and intracellular sac-charification of starch. 相似文献
4.
Gurdev S. Khush Sichul Lee Jung-Il Cho Jong-Seong Jeon 《Plant biotechnology reports》2012,6(3):195-202
Micronutrient deficiencies affect approximately 3 billion people worldwide. Malnutrition hinders the development of human potential and social and economic development in developing countries. The World Health Organization (WHO) and the Consultative Group on International Agricultural Research (CGIAR) have made fighting micronutrient deficiencies, known as hidden hunger, a high priority. Deficiencies of the micronutrients, such as iron, zinc, and vitamin A, are the most devastating among the world’s poor. WHO emphasizes nutrient supplementation and food fortification to address the malnutrition. CGIAR has placed a greater emphasis on biofortification through the HarvestPlus challenge program, and improved micronutrient content of the staple crops (rice, wheat, maize, beans, cassava, pearl millet, and sweet potato) through breeding and biotechnological approaches. An excellent example of biotechnology application is the development of ‘golden rice’ with adequate levels of a provitamin A, β-carotene. The Africa Harvest and the BioCassava Plus programs, respectively, are developing sorghum and cassava with improved nutritional quality. Here, we summarize current strategies of crop biofortification and future prospects towards the development of biofortified crops. 相似文献
5.
Mahanama De Zoysa Chamilani Nikapitiya You-Jin Jeon Youngheun Jee Jehee Lee 《Journal of applied phycology》2008,20(1):67-74
A sulfated polysaccharide with anticoagulant properties was isolated from the fermented brown seaweed Sargassum fulvellum. Freeze-dried S. fulvellum was fermented in an incubator for 10th week at 25°C to convert seaweed macromolecules into anticoagulant sulfated polysaccharides (ASP). Anticoagulant activity
was determined by an activated partial thromboplastin time (APTT) test using citrated human blood plasma. The 8th week S. fulvellum crude seaweed extract (SWE) exhibited the highest blood anticoagulant activity. Therefore, 8th week crude SWE was used for purification of ASP by two steps; DEAE cellulose anion-exchange followed by Sepharose 4B chromatography.
The isolated ASP showed a single spot on agarose gel electrophoresis, which confirmed the purification status of our ASP.
Polyacrylamide gel electrophoresis (PAGE) analysis showed that the molecular mass of the purified ASP was between 8 and 20 kDa.
Polysaccharide and sulfate concentrations of the purified ASP were 180 and 29.70 μg mL−1 respectively. ASP recovery was 1.32% (w/w) from the crude polysaccharide applied to the DEAE column. Purified ASP had a pH
of 3.86 and was considered an acidic polysaccharide. Moreover, both ASP and heparin showed a relative clotting factor of 27.47
at the concentrations of 180 and 60 μg mL−1 respectively. Therefore, S. fulvellum ASP can be considered a weaker anticoagulant than heparin. Results of the APTT, PT, and TT clotting assays showed that ASP
was able to inhibit both intrinsic and extrinsic blood coagulation pathways. Finally, this study established a feasible and
simple experimental protocol to isolate anticoagulant from fermented seaweeds leading to potential further development of
anticoagulant agent for the pharmaceutical industry. 相似文献
6.
Virginia Edgcomb William Orsi John Bunge Sunok Jeon Richard Christen Chesley Leslin Mark Holder Gordon T Taylor Paula Suarez Ramon Varela Slava Epstein 《The ISME journal》2011,5(8):1344-1356
Microbial diversity and distribution are topics of intensive research. In two companion papers in this issue, we describe the results of the Cariaco Microbial Observatory (Caribbean Sea, Venezuela). The Basin contains the largest body of marine anoxic water, and presents an opportunity to study protistan communities across biogeochemical gradients. In the first paper, we survey 18S ribosomal RNA (rRNA) gene sequence diversity using both Sanger- and pyrosequencing-based approaches, employing multiple PCR primers, and state-of-the-art statistical analyses to estimate microbial richness missed by the survey. Sampling the Basin at three stations, in two seasons, and at four depths with distinct biogeochemical regimes, we obtained the largest, and arguably the least biased collection of over 6000 nearly full-length protistan rRNA gene sequences from a given oceanographic regime to date, and over 80 000 pyrosequencing tags. These represent all major and many minor protistan taxa, at frequencies globally similar between the two sequence collections. This large data set provided, via the recently developed parametric modeling, the first statistically sound prediction of the total size of protistan richness in a large and varied environment, such as the Cariaco Basin: over 36 000 species, defined as almost full-length 18S rRNA gene sequence clusters sharing over 99% sequence homology. This richness is a small fraction of the grand total of known protists (over 100 000–500 000 species), suggesting a degree of protistan endemism. 相似文献
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8.
Jin-Hwan Cho Heeyoun Hwang Man-Ho Cho Yong-Kook Kwon Jong-Seong Jeon Seong Hee Bhoo Tae-Ryong Hahn 《Journal of Plant Biology》2008,51(4):297-301
Rubisco is a major photosynthetic plant enzyme in the chloroplasts, catalyzing a photosynthetic reaction through carboxylation
and oxygenation in the leaves. Despite its biological importance, its high abundance causes difficulties in the proper separation
of protein mixtures during 2-dimensional gel electrophoresis (2-DE). Here, we resolved those plant soluble proteins by efficiently
removing Rubisco. This resulted in a high quality and resolution of 2-DE gels. Rubisco removal was achieved through aggregation
in the presence of a high DTT concentration, which subsequently increased the visualization of less abundant proteins and
reduced horizontal streaking. This simple method may provide a means for finding more biologically important protein targets
via plant proteomics. 相似文献
9.
Yoon Jeong Lee Han-Gyu Bae Hyung-Bae Jeon Dong-Young Kim 《Animal cells and systems.》2017,21(5):349-357
Endemic species typically have a narrow niche breadth, and are likely more vulnerable to extinction than more widespread taxa. Squalidus multimaculatus is a small cyprinid endemic to the Korean Peninsula, and its reported geographical range was restricted to several small rivers located along the southeast coast. Several populations of S. multimaculatus have supposedly been subject to a variety of recent anthropogenic actions. Here, we analyzed the pattern of genetic diversity within and among populations of S. multimaculatus using nine microsatellite loci to quantify the relative contributions of human-mediated processes to the contemporary distribution and genetic structure. Overall, low levels of genetic diversity were exhibited in the populations of S. multimaculatus. Genetic differentiations among populations were not completely represented by their geographical proximity, likely resulting from the low intrapopulation genetic variability and anthropogenic transplants. The most conspicuous outcome of the anthropogenic activities was the introgression of alleles from a closely related species, S. gracilis majimae. Our study showed that anthropogenic transplanting, even with only a small number of individuals, can challenge our conservation goal to maintain the species integrity that has long been shaped in evolutionary processes. 相似文献
10.
Hong Jun Jeon Young Rong Bang Hye Youn Park Seul A. Kim 《Chronobiology international》2017,34(6):677-686
Various physiological and psychological functions are influenced by circadian typology (CT), which was reported to be related to resilience. However, few studies have assessed the effects of CT in relation to resilience. The aim of the present study was to assess the influence of CT on sleep-related symptoms, physical fatigue and psychological well-being in relation to resilience. The present study included a total of 1794 healthy hospital employees, and they completed the Morningness–Eveningness Questionnaire, Connor–Davidson Resilience Scale, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Fatigue Severity Scale, Hospital Anxiety and Depression Scale and World Health Organization Quality of Life Scale Abbreviated Version. Subjects with evening type showed lower sleep quality, more daytime sleepiness and physical fatigue than neither types and morning types. Additionally, evening types were more depressed and anxious and reported a poorer quality of life. CT was found to be a significant predictor of sleep quality, but CT was minimally associated with physical fatigue and psychological well-being in the regression analysis. Instead, resilience was substantially related to all of the variables measured. In conclusion, CT independently predicts sleep quality, but the effects of CT on physical fatigue and psychological well-being are negligible compared to those of resilience. 相似文献