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931.
Reza Khakvar Kamaruzaman Sijam Kwai Lin Thong Son Radu Mui Yun Wong Jeffery Jones 《Archives Of Phytopathology And Plant Protection》2013,46(6):594-601
Abstract Surveys were conducted between the years of 2005 and 2006 at several locations in the northern, central and southern parts of West Malaysia to study the polymorphism of Ralstonia solanacearum strains. These sites included vegetables and farms with known hosts of the pathogen, such as banana, tomato, eggplant, chili and tobacco. Samples were collected from the suspected wilted plants and weeds, including soil and water samples, in selected areas. The bacterium was isolated in all samples using semi-selective tetrazolium chloride medium (TZC). The bacteria strains were detected by using the BIOLOG identification system and were confirmed by nested-PCR. Fatty Acid Methyl Esters (FAME) profiling was performed to determine polymorphism among 58 bacterial isolates. The results showed that the fatty acid composition varied for all R. solanacearum isolates. Grouping of R. solanacearum isolates by fatty acid composition suggested that the existence of distinct groups that were significantly related to host of bacteria but low correlation between fatty acid profiles and biovar or sampling site was detected. A unique FAME profile was found among the strains that have been isolated from banana. 相似文献
932.
Sarah P. Walters Narjol González-Escalona Insook Son David C. Melka Lauren M. Sassoubre Alexandria B. Boehm 《Applied and environmental microbiology》2013,79(14):4199-4209
Salmonella enterica is one of the most important bacterial enteric pathogens worldwide. However, little is known about its distribution and diversity in the environment. The present study explored the diversity of 104 strains of Salmonella enterica isolated over 2 years from 12 coastal waterways in central California. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing were used to probe species diversity. Seventy-four PFGE patterns and 38 sequence types (STs) were found, including 18 newly described STs. Nineteen of 25 PFGE patterns were indistinguishable from those of clinical isolates in PulseNet. The most common ST was consistent with S. enterica serovar Typhimurium, and other frequently detected STs were associated with the serovars Heidelberg and Enteritidis; all of these serovars are important etiologies of salmonellosis. An investigation into S. enterica biogeography was conducted at the level of ST and subspecies. At the ST and subspecies level, we found a taxon-time relationship but no taxon-area or taxon-environmental distance relationships. STs collected during wet versus dry conditions tended to be more similar; however, STs collected from waterways adjacent to watersheds with similar land covers did not tend to be similar. The results suggest that the lack of dispersal limitation may be an important factor affecting the diversity of S. enterica in the region. 相似文献
933.
Hye-Nam Son Ju-Ock Nam Soyoun Kim In-San Kim 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2013,1833(10):2378-2388
TGFBI, a transforming growth factor β-induced extracellular matrix protein, circulates at a level of ~ 300 ng/ml in humans and modulates several integrin-mediated cellular functions. The protein contains an N-terminal EMI domain, four consecutive FAS1 domains, and the RGD motif. Each FAS1 domain and the RGD motif have been known to interact with avb3 integrin. Here, we found that the binding affinity (Kd) of TGFBI for αvβ3 integrin was approximately 3.8 × 10? 8 M, a value ~ 2300-fold higher than that of a single FAS1 domain, and demonstrated that this greater affinity was due to the cooperative action of the four FAS1 domains and the RGD motif. Moreover, TGFBI exhibited more potent anti-angiogenic and anti-tumorigenic activities, even at a 100-fold lower molar dose than the reported effective dose of the FAS1 domain. Finally, our data showed that TGFBI specifically targeted the tumor vasculature and accumulated at the tumor site. Collectively, our results support the theory that TGFBI acts as a potent endogenous anti-tumor and anti-angiogenic molecule by targeting αvβ3 integrin, and highlights the importance of physiological circulating TGFBI levels in inhibiting tumor growth. 相似文献
934.
Gunsup Lee Hye-Kyung Shim Myung-Hee Kwon Su-Hwan Son Ki-Yoon Kim Eul-Yong Park Taek-Kyun Lee Woo-Ram Lee Chung-Kyoon Auh Donggiun Kim Yong-Sung Kim Sukchan Lee 《Plant Cell, Tissue and Organ Culture》2013,115(2):179-187
A catalytic single chain variable antibody (scFv), 3D8 scFv, which has DNase activities, was functionally expressed in Nicotiana tabacum. The subcellular localization of the GFP-fused 3D8 indicated that the 3D8 protein was expressed in the cytosol of the N. tabacum protoplasts. Progenies of the transgenic tobacco plants exhibited complete resistance against two single stranded (ss) DNA geminiviruses, including the Beet curly top virus and the Beet severe curly top virus, without viral accumulation or disease symptoms. We presented a novel strategy for targeting the viral DNA itself in a sequence non-specific manner, rather than the viral proteins or RNAs, in order to generate virus-resistant transgenic plants. No noticeable adverse effects on the growth and reproduction of the transgenic plants were observed. Our results demonstrated that targeting viral DNA is an effective strategy for protecting plants from ssDNA viruses. 相似文献
935.
To investigate the factors associated with compliance with recommendations regarding liver cancer screening intervals and methods among individuals at high-risk for liver cancer in the Republic of Korea. We used data from the fourth Korean National Health and Nutrition Examination Survey (KNHANES IV), a representative cross-sectional nationwide survey conducted between 2007 and 2009. The liver cancer screening rate and factors associated with compliance with recommended screening intervals (6 months) and methods (both abdominal ultrasonography and serum alpha-fetoprotein testing) among individuals at high risk for liver cancer such as hepatitis B virus (HBV) carriers were investigated. Out of 24,871 KNHANES IV participants, 604 HBV carriers aged ≥20 years were included in our analysis. 39.6% of our study sample reported attending liver cancer screening at least once in their lifetime, 12.3% had attended within the previous 6 months, and 14.6% were screened using both recommended methods. Older age was associated with increased compliance with screening intervals (P-trend 0.011) and methods (40–49 year: OR = 3.25, 95% CI: 1.62–6.51; 50–59 years: OR = 3.09, 95% CI: 1.44–6.66; 60–69 years: OR = 3.17, 95% CI: 1.28–7.82). Unawareness of HBV infection status was negatively related to compliance with screening intervals and methods (OR = 0.30, 95% CI: 0.17–0.53; OR = 0.45, 95% CI: 0.26–0.79). Female sex (OR = 0.45, 95% CI: 0.25–0.78), lower household income (P-trend 0.011), and routine and manual occupations (OR = 0.46, 95% CI: 0.22–0.97) were associated with decreased compliance with screening methods. The liver cancer screening rate among high-risk individuals is much less suboptimal. Considering that those unaware of their HBV infection status got regular and complete liver cancer screening much less often, efforts should be made not only to decrease sociodemographic disparities, but also to better identify the high-risk population. 相似文献
936.
Modifiable lifestyle-related factors such as smoking and alcohol drinking are associated with cognitive impairment in the elderly population but the relationships have shown various results. To evaluate the relationship of alcohol drinking and smoking in the early 60 s with the risk of developing incident cognitive impairment. In 1999, we evaluated cognitive function, smoking, and drinking status in 3,174 inhabitants aged 60–64 years in a rural area of Korea, with a follow-up assessment of cognitive function 7 years later. A total of 1,810 individuals who did not show cognitive impairment at baseline were included. A stratified analysis was applied to evaluate how smoking and alcohol drinking affected the risk of developing cognitive impairment based on gender. Current smokers showed a higher risk for developing cognitive impairment than did never smokers (odds ratio [OR], 1.53; 95% confidence interval [CI], 1.09–2.15). The OR for female current smokers compared with never smokers was 1.62 (95% CI, 1.05–2.52), and smokers with higher pack-years were more likely to develop cognitive impairment than never smokers, showing a dose–response relationship (P for trend = 0.004). Frequent alcohol consumption increased the risk of developing cognitive impairment (OR, 1.68; 95% CI, 1.01–2.78), and a dose–response relationship was observed among male subjects (P for trend = 0.044). Infrequent drinking in females decreased the odds of developing cognitive impairment (OR, 0.67; 95% CI, 0.42–1.00), whereas frequent drinking tended to increase the odds, although this trend was not significant, suggesting a U-shaped relationship. Although the sample was small for some analyses, especially in female, our data suggest that smoking and drinking in the early 60 s are associated with a risk of developing cognitive impairment, and this relationship is characterized by gender differences. 相似文献
937.
Aesun Shin Kui Son Choi Jae Kwan Jun Dai Keun Noh Mina Suh Kyu-Won Jung Byung Chang Kim Jae Hwan Oh Eun-Cheol Park 《PloS one》2013,8(11)
Aim
The aims of the current study were to assess the validity of the fecal occult blood test (FOBT) in an organized screening setting in Korea and to determine factors associated with FOBT validity, such as screening round, age group, and anatomical location of the cancer.Methods
Study participants were those who were 50 years and older who received an FOBT through the National Cancer Screening Program between 2004 and 2007. Colorectal cancer diagnoses were ascertained through linkage with the Korean National Cancer Incidence Database. The positivity rate, colorectal cancer detection rate, interval cancer rate, sensitivity, specificity, and positive predictive value of the FOBT were calculated.Results
A total of 2,193,093 tests were included in the analysis. Overall, the sensitivity of the FOBT for colorectal cancer was 59.7% for the first round and 56.1% for the subsequent round. Sensitivity was highest for distal colon cancer (65.9%) in the first round, and for rectal cancer (58.4%) for the subsequent round. The sensitivity and positive predictive value of the FOBT generally improved between 2004 and 2008.Conclusions
The FOBT showed reasonable validity in an organized screening setting, and the validity of the FOBT varied by screening round, anatomical location, and screening year. 相似文献938.
Myoungki Son Minjung Lee Gi-Ho Sung Taeho Lee Yu Su Shin Hyosun Cho Paul M. Lieberman Hyojeung Kang 《Journal of microbiology (Seoul, Korea)》2013,51(5):545-551
More than 90% of adults have been infected with at least one human herpesvirus, which establish long-term latent infection for the life of the host. While anti-viral drugs exist that limit herpesvirus replication, many of these are ineffective against latent infection. Moreover, drug-resistant strains of herpesvirus emerge following chemotherapeutic treatment. For example, resistance to acyclovir and related nucleoside analogues can occur when mutations arise in either HSV thymidine kinase or DNA polymerases. Thus, there exists an unmet medical need to develop new anti-herpesvirus agents with different mechanisms of action. In this Review, we discuss the promise of anti-herpetic substances derived from natural products including extracts and pure compounds from potential herbal medicines. One example is Glycyrrhizic acid isolated from licorice that shows promising antiviral activity towards human gammaherpesviruses. Secondly, we discuss anti-herpetic mechanisms utilized by several natural products in molecular level. While nucleoside analogues inhibit replicating herpesviruses in lytic replication, some natural products can disrupt the herpesvirus latent infection in the host cell. In addition, natural products can stimulate immune responses against herpesviral infection. These findings suggest that natural products could be one of the best choices for development of new treatments for latent herpesvirus infection, and may provide synergistic anti-viral activity when supplemented with nucleoside analogues. Therefore, it is important to identify which natural products are more efficacious anti-herpetic agents, and to understand the molecular mechanism in detail for further advance in the anti-viral therapies. 相似文献
939.
Min Jeong Ku Jong Woo Park Byung Jun Ryu Young-Jin Son Seong Hwan Kim Sang Yeol Lee 《Bioorganic & medicinal chemistry letters》2013,23(20):5609-5613
Casein kinase 2 (CK2) is known to be involved in various cellular processes such as cell cycle, apoptosis and proliferation. It has been reported that the inhibition of CK2 induced by recently developed small molecule CX4945 shows anti-cancer effects including anti-proliferation and anti-angiogenesis in several different cancers including prostate cancer. Here we report that migration and invasion of A549 human lung cancer cells are suppressed by the inhibition of CK2 induced by CX4945. We found that CX4945 sequentially attenuates the proteins in PI3K/Akt and MAPK pathways, two signaling pathways related with cell migration. This sequential control of signal pathways inhibits the expression of membrane type 1-matrix metalloproteinase and this leads to the selective attenuation of one of the gelatinases, MMP-2, which can degrade components of extracellular matrix, and metastasis of A549 human lung cancer cell. 相似文献
940.
Previously, we identified a novel herbivore elicitor-regulated protein in Nicotiana attenuata (NaHER1) that is required to suppress abscisic acid (ABA) catabolism during herbivore attack and activate a full defense response against herbivores. ABA, in addition to its newly defined role in defense activation, mainly controls seed germination and stomatal function of land plants. Here we show that N. attenuata seeds silenced in the expression of NaHER1 by RNA interference (irHER1) accumulated less ABA during germination, and germinated faster on ABA-containing media compared to WT. Curiously, epidermal cells of irHER1 plants were wrinkled, possibly due to the previously demonstrated increase in transpiration of irHER1 plants that may affect turgor and cause wrinkling of the cells. We conclude that NaHER1 is a highly pleiotropic regulator of ABA responses in N. attenuata plants. 相似文献