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81.
Gabriella M. Anic Vernon K. Sondak Jane L. Messina Neil A. Fenske Jonathan S. Zager Basil S. Cherpelis Ji-Hyun Lee William J. Fulp Pearlie K. Epling-Burnette Jong Y. Park Dana E. Rollison 《Cancer epidemiology》2013,37(4):434-439
Background: Telomeres help maintain chromosomal structure and may influence tumorigenesis. We examined the association between telomere length and skin cancer in a clinic-based case-control study of 198 melanoma cases, 136 squamous cell carcinoma (SCC) cases, 185 basal cell carcinoma (BCC) cases, and 372 healthy controls. Methods: Cases were histologically confirmed patients treated at the Moffitt Cancer Center and University of South Florida Dermatology Clinic in Tampa, FL. Controls self-reported no history of cancer and underwent a skin cancer screening exam at study enrollment to rule out the presence of skin cancer. Quantitative real time PCR was used to measure telomere length in peripheral blood samples. Results: Melanoma patients had longer telomeres than controls (odds ratio (OR) = 3.75; 95% confidence interval (CI): 2.02–6.94 for highest versus lowest tertile) (P for trend = <0.0001). In contrast, longer telomere length was significantly inversely associated with SCC (OR = 0.01; 95% CI: 0.00–0.05 for highest versus lowest tertile) (P for trend = <0.0001) and BCC (OR = 0.10; 95% CI: 0.06–0.19 for highest versus lowest tertile) (P for trend = <0.0001). Conclusion: Telomere length may be involved in the development of skin cancer, although the effect on cancer risk differs for melanoma and non-melanoma carcinomas. Our findings suggest that long telomere length is positively associated with melanoma while inversely associated with SCC and BCC. 相似文献
82.
Discovery of genes for ginsenoside biosynthesis by analysis of ginseng expressed sequence tags 总被引:12,自引:0,他引:12
Expressed sequence tags (ESTs) provide a valuable tool that can be used to identify genes in secondary metabolite biosynthesis. Ginseng (Panax ginseng C.A Meyer) is a medicinal plant that accumulates ginsenosides in roots. We sequenced 11,636 ESTs from five ginseng libraries in order to create a gene resource for biosynthesis of ginsenosides, which are thought to be the major active component in roots. Only 59% of the ginseng ESTs exhibited significant homology to previously known polypeptide sequences. Stress- and pathogen-response proteins were most abundant in 4-year-old ginseng roots. ESTs involved in ginsenoside biosynthesis were identified by a keyword search of BLASTX results and a domain search of ginseng ESTs. We identified 4 oxidosqualene cyclase candidates involved in the cyclization reaction of 2,3-oxidosqualene, 9 nine cytochrome P450 and 12 glycosyltransferse candidates, which may be involved in modification of the triterpene backbone.Abbreviations cDNA Complementary DNA - ESTs Expressed sequence tagsCommunicated by I.S. Chung 相似文献
83.
Antonia Sophie Wenners Keyur Mehta Sibylle Loibl Hyerim Park Berit Mueller Norbert Arnold Sigrid Hamann Joerg Weimer Beyhan Ataseven Silvia Darb-Esfahani Christian Schem Christoph Mundhenke Fariba Khandan Christoph Thomssen Walter Jonat Hans-Juergen Holzhausen Gunther von Minckwitz Carsten Denkert Maret Bauer 《PloS one》2012,7(10)
In our previous work we showed that NGAL, a protein involved in the regulation of proliferation and differentiation, is overexpressed in human breast cancer (BC) and predicts poor prognosis. In neoadjuvant chemotherapy (NACT) pathological complete response (pCR) is a predictor for outcome. The aim of this study was to evaluate NGAL as a predictor of response to NACT and to validate NGAL as a prognostic factor for clinical outcome in patients with primary BC. Immunohistochemistry was performed on tissue microarrays from 652 core biopsies from BC patients, who underwent NACT in the GeparTrio trial. NGAL expression and intensity was evaluated separately. NGAL was detected in 42.2% of the breast carcinomas in the cytoplasm. NGAL expression correlated with negative hormone receptor (HR) status, but not with other baseline parameters. NGAL expression did not correlate with pCR in the full population, however, NGAL expression and staining intensity were significantly associated with higher pCR rates in patients with positive HR status. In addition, strong NGAL expression correlated with higher pCR rates in node negative patients, patients with histological grade 1 or 2 tumors and a tumor size <40 mm. In univariate survival analysis, positive NGAL expression and strong staining intensity correlated with decreased disease-free survival (DFS) in the entire cohort and different subgroups, including HR positive patients. Similar correlations were found for intense staining and decreased overall survival (OS). In multivariate analysis, NGAL expression remained an independent prognostic factor for DFS. The results show that in low-risk subgroups, NGAL was found to be a predictive marker for pCR after NACT. Furthermore, NGAL could be validated as an independent prognostic factor for decreased DFS in primary human BC. 相似文献
84.
Jin CH Krishnaiah M Sreenu D Subrahmanyam VB Rao KS Mohan AV Park CY Son JY Sheen YY Kim DK 《Bioorganic & medicinal chemistry letters》2011,21(20):6049-6053
A series of 1-substituted-3-(6-methylpyridin-2-yl)-4-([1,2,4]triazolo[1,5-a]pyridin-6-yl)pyrazoles 14a-ae, 16a, 16b, and 21a-c has been prepared and evaluated for their ALK5 inhibitory activity in an enzyme assay and in a cell-based luciferase reporter assay. The 4-([1,2,4]triazolo[1,5-a]pyridin-6-yl)-N-(4-methoxyphenyl)-3-(6-methylpyridin-2-yl)-1H-pyrazole-1-carbothioamide (14n) inhibited ALK5 phosphorylation with IC(50) value of 0.57 nM and showed 94% inhibition at 100 nM in a luciferase reporter assay using HaCaT cells permanently transfected with p3TP-luc reporter construct. 相似文献
85.
Sun Jae Kwon Hak Chul Jin Soohyun Lee Myung Hee Nam Joo Hee Chung Soon Il Kwon Choong-Min Ryu Ohkmae K. Park 《The Plant journal : for cell and molecular biology》2009,58(2):235-245
Systemic resistance is induced by necrotizing pathogenic microbes and non-pathogenic rhizobacteria and confers protection against a broad range of pathogens. Here we show that Arabidopsis GDSL LIPASE-LIKE 1 (GLIP1) plays an important role in plant immunity, eliciting both local and systemic resistance in plants. GLIP1 functions independently of salicylic acid but requires ethylene signaling. Enhancement of GLIP1 expression in plants increases resistance to pathogens including Alternaria brassicicola , Erwinia carotovora and Pseudomonas syringae , and limits their growth at the infection site. Furthermore, local treatment with GLIP1 proteins is sufficient for the activation of systemic resistance, inducing both resistance gene expression and pathogen resistance in systemic leaves. The PDF1.2 -inducing activity accumulates in petiole exudates in a GLIP1-dependent manner and is fractionated in the size range of less than 10 kDa as determined by size exclusion chromatography. Our results demonstrate that GLIP1-elicited systemic resistance is dependent on ethylene signaling and provide evidence that GLIP1 may mediate the production of a systemic signaling molecule(s). 相似文献
86.
The D3S20-D3S34-D3S3 region on BTA3 contains quantitative trait loci (QTL) controlling milk production traits. This region also displays extensive conservation of synteny among several species including cattle, humans, mice and sheep. In this study, we evaluated the adjacent intervals D3S20-D3S34 and D3S34-D3S3 for differences in recombination rate (theta) among bulls in order to assess the suitability of population-based estimates of theta for marker assisted selection and to explore the relationship between variation in theta and chromosome breakpoints associated with mammalian evolution. Using sperm typing, thetaD3S20-D3S34 and theta D3S34-D3S3 were estimated for six triply heterozygous bulls. Recombination frequency ranged from 6.2 to 12.5% and from 9.7 to 19.2% for the D3S20-D3S34 and D3S34-D3S3 intervals, respectively. However, significant variation in theta was not detected between bulls for either interval (D3S20-D3S34 chi(2)5 d.f.=2.59, P < 0.90; D3S34-D3S3 chi(2)5 d.f.=3.72, P < 0.75). The observed differences in theta were most readily attributed to differences in allele-specific amplification efficiencies among bulls. Our results suggest that the positions of QTL in this region can be reliably determined from population data and therefore accurate marker-assisted selection can be performed for desirable alleles without concern for variation in theta. Furthermore, when considered with results of earlier studies, these findings support a correlation between the existence of evolutionary breakpoints or chromosome rearrangements and variation in theta. 相似文献
87.
88.
An anxiety-related behavior is an emotional response of an organism, which is quantitatively measured by several behavioral paradigms. We employed two most frequently used behavioral tests, the open field and light-dark exploration, to comparatively analyze the anxiety-like behaviors in four inbred mice. For an accurate recording of movement, motion analysis software was developed that acquires a real-time video input to generate a behavioral path. Effects of the strains on the test results were evaluated by ANOVA with the Newman-Keuls post hoc comparison. Eight different behavioral indices, four from each tests, were grouped into two classes; the results of duration, center crossing, transition, rearing, and ambulation indicate strain differences of FVB/N>C57BL/6J>/=BALB/cA>/=CBA/N (I), while stretched-attend posture, peeping, and defecation show the tendency of FVB/N=C57BL/6J相似文献
89.
Doo Hyun Park 《Bioscience, biotechnology, and biochemistry》2018,82(7):1234-1242
Bacterial communities and metabolites in kimchi fermented under conventional conditions (CC) compared to CO2-rich environments (CO2) were analyzed. After a 20-day fermentation, lactic and acetic acid productions were 54 and 69 mM under CC, and 19 and 12 mM under CO2, respectively. The final pH of kimchi fermented under CC (CC-fermenting) and CO2 (CO2-fermenting) were 4.1 and 4.7, respectively. For bacterial communities, OTU and Chao1 indices were both 35 in fresh kimchi, 10 and 15 in CC-fermenting kimchi, and 8 and 24 in CO2-fermenting kimchi, respectively. Shannon and Simpson indices were 3.47 and 0.93 in fresh kimchi, 1.87–0.06 and 0.46–0.01 in CC-fermenting kimchi, and 1.65–0.44 and 0.63–0.12 in CO2-fermenting kimchi, respectively. Non-lactic acid bacteria were eliminated in fermenting kimchi after 12 days under CC and 6 days under CO2. I conclude that carbon dioxide can alter bacterial communities, reduce metabolite production, and improve fermented kimchi quality. 相似文献
90.
S. H. Park R. T. Raines 《Protein science : a publication of the Protein Society》1997,6(11):2344-2349
Green fluorescent protein (GFP) is autofluorescent. This property has made GFP useful in monitoring in vivo activities such as gene expression and protein localization. We find that GFP can be used in vitro to reveal and characterize protein-protein interactions. The interaction between the S-peptide and S-protein fragments of ribonuclease A was chosen as a model system. GFP-tagged S-peptide was produced, and the interaction of this fusion protein with S-protein was analyzed by two distinct methods: fluorescence gel retardation and fluorescence polarization. The fluorescence gel retardation assay is a rapid method to demonstrate the existence of a protein-protein interaction and to estimate the dissociation constant (Kd) of the resulting complex. The fluorescence polarization assay is an accurate method to evaluate Kd in a specified homogeneous solution and can be adapted for the high-throughput screening of protein or peptide libraries. These two methods are powerful new tools to probe protein-protein interactions. 相似文献