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461.
ABSTRACTThe brightly blue shallow water species Terpios fugax Duchassaing and Michelotti, 1864 was originally described from the Caribbean and has been extensively recorded in the Atlantic Ocean, but rarely found in the Indian and Pacific Oceans. In the Pacific Ocean it has been only reported from Sulawesi, Indonesia and from the Caroline and Marshall Islands. Here we report the first record of Terpios in the Eastern Pacific, based on the presence of T. fugax at Caldera, Región de Atacama, northern Chile. Although this species may have been inadvertently introduced to the area by human activity, it should also be considered that the geographically distant populations of this sponge (from the Caribbean to the Eastern Pacific) may represent different species. 相似文献
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Maximo Paulino T. Sison III 《Ocean Development & International Law》2018,49(2):157-175
This article argues that a resolution of the maritime disputes in the South China Sea must be based upon a universalist framework where the maritime interests of the world are upheld. The article discusses the universalist framework of the 1982 United Nations Convention on the Law of the Sea (UNCLOS) and the universalist approach taken by the Tribunal on 12 July 2016 in the South China Sea Arbitration regarding the extinguishment of a state's “exceptionalist” maritime claims and the adoption of strict criteria for the characterization of features at sea. 相似文献
464.
Taryn D. Treger Tasnim Chagtai Robert Butcher George D. Cresswell Reem Al-Saadi Jesper Brok Richard D. Williams Chrissy Roberts Nicholas M. Luscombe Kathy Pritchard Jones William Mifsud 《Translational oncology》2018,11(6):1301-1306
BACKGROUND: Diffuse anaplastic Wilms tumor (DAWT) is a rare, high-risk subtype that is often missed on diagnostic needle biopsy. Somatic mutations in TP53 are associated with the development of anaplasia and with poorer survival, particularly in advanced-stage disease. Early identification of DAWT harboring TP53 abnormalities could improve risk stratification of initial therapy and monitoring for recurrence. METHODS: Droplet digital polymerase chain reaction (ddPCR) was used to evaluate 21 samples from 4 patients with DAWT. For each patient, we assessed TP53 status in frozen tumor, matched germline DNA, and circulating tumor DNA (ctDNA) from plasma, serum, and urine collected throughout treatment. RESULTS: Mutant TP53 was detectable in ctDNA from plasma and serum in all patients. We did not detect variant TP53 in the same volume (200 μl) of urine. One patient displayed heterogeneity of TP53 in the tumor despite both histological sections displaying anaplasia. Concentration of ctDNA from plasma/serum taken prenephrectomy varied significantly between patients, ranging from 0.44 (0.05-0.90) to 125.25 (109.75-140.25) copies/μl. We observed variation in ctDNA throughout treatment, and in all but one patient, ctDNA levels fell significantly following nephrectomy. CONCLUSION: We demonstrate for the first time that ddPCR is an effective method for detection of mutant TP53 in ctDNA from children with DAWT even when there is intratumoral somatic heterogeneity. This should be further explored in a larger cohort of patients, as early detection of circulating variant TP53 may have significant clinical impact on future risk stratification and surveillance. 相似文献
465.
Effect of land-use change and methane mixing ratio on methane uptake from United Kingdom soil 总被引:1,自引:0,他引:1
Methane (CH4) is a trace gas 30 times more radiatively active than carbon dioxide and, apart from a recent decrease, its atmospheric concentration has been increasing at a rate of ~ 1%per annum since 1945. The increase results from an imbalance between CH4 production and consumption. Here we assess the impact that changes in land use and increasing atmospheric CH4 mixing ratios have had on CH4 uptake rates by soil in the UK since before the Iron age. This has been achieved by making retrospective analyses of CH4 uptake in UK soils under four different conditions of land use and CH4 mixing ratio. The calculations indicate that 54% of the current CH4 uptake by UK soils is the result of increased CH4 mixing ratio but that land-use change has caused a reduction of ~ 37 kt CH4 y?1 in the potential sink strength of UK soils for CH4. The results are discussed with respect to the compilation of greenhouse gas inventories. 相似文献
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John L. Woodard Andrew C. Huntsman Pratiq A. Patel Hee-Byung Chai Ragu Kanagasabai Soumendrakrishna Karmahapatra Alexandria N. Young Yulin Ren Malcolm S. Cole Denisse Herrera Jack C. Yalowich A. Douglas Kinghorn Joanna E. Burdette James R. Fuchs 《Bioorganic & medicinal chemistry》2018,26(9):2354-2364
A series of arylnaphthalene lignan lactones based on the structure of the phyllanthusmins, a class of potent natural products possessing diphyllin as the aglycone, has been synthesized and screened for activity against multiple cancer cell lines. SAR exploration was performed on both the carbohydrate and lactone moieties of this structural class. These studies have revealed the importance of functionalization of the carbohydrate hydroxy groups with both acetylated and methylated analogues showing increased potency relative to those with unsubstituted sugar moieties. In addition, the requirement for the presence and position of the C-ring lactone has been demonstrated through reduction and selective re-oxidation of the lactone ring. The most potent compound in this study displayed an IC50 value of 18?nM in an HT-29 assay with several others ranging from 50 to 200?nM. In an effort to elucidate their potential mechanism(s) of action, the DNA topoisomerase IIa inhibitory activity of the most potent compounds was examined based on previous reports of structurally similar compounds, but does not appear to contribute significantly to their antiproliferative effects. 相似文献
468.
Temperature alone does not explain phenological variation of diverse temperate plants under experimental warming
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Renée M. Marchin Carl F. Salk William A. Hoffmann Robert R. Dunn 《Global Change Biology》2015,21(8):3138-3151
Anthropogenic climate change has altered temperate forest phenology, but how these trends will play out in the future is controversial. We measured the effect of experimental warming of 0.6–5.0 °C on the phenology of a diverse suite of 11 plant species in the deciduous forest understory (Duke Forest, North Carolina, USA) in a relatively warm year (2011) and a colder year (2013). Our primary goal was to dissect how temperature affects timing of spring budburst, flowering, and autumn leaf coloring for functional groups with different growth habits, phenological niches, and xylem anatomy. Warming advanced budburst of six deciduous woody species by 5–15 days and delayed leaf coloring by 18–21 days, resulting in an extension of the growing season by as much as 20–29 days. Spring temperature accumulation was strongly correlated with budburst date, but temperature alone cannot explain the diverse budburst responses observed among plant functional types. Ring‐porous trees showed a consistent temperature response pattern across years, suggesting these species are sensitive to photoperiod. Conversely, diffuse‐porous species responded differently between years, suggesting winter chilling may be more important in regulating budburst. Budburst of the ring‐porous Quercus alba responded nonlinearly to warming, suggesting evolutionary constraints may limit changes in phenology, and therefore productivity, in the future. Warming caused a divergence in flowering times among species in the forest community, resulting in a longer flowering season by 10‐16 days. Temperature was a good predictor of flowering for only four of the seven species studied here. Observations of interannual temperature variability overpredicted flowering responses in spring‐blooming species, relative to our warming experiment, and did not consistently predict even the direction of flowering shifts. Experiments that push temperatures beyond historic variation are indispensable for improving predictions of future changes in phenology. 相似文献
469.
Nimesulide is a nonsteroidal anti-inflammatory drug possessing analgesic and antipyretic properties. This drug is considered a selective cyclooxygenase-2 (COX-2) inhibitor and, more recently, has been associated to antitumor activity. Thus, numerous works have been developed to modify the nimesulide skeleton aiming to develop new and more potent and selective COX-2 inhibitors as well as potential anticancer agents. This review intends to provide an overview on analogues of nimesulide, including the general synthetic approaches used for their preparation and structural diversification and their main anti-inflammatory and/or antitumor properties. 相似文献
470.
Modular design is at the foundation of contemporary engineering, enabling rapid, efficient, and reproducible construction and maintenance of complex systems across applications. Remarkably, modularity has recently been discovered as a governing principle in natural biological systems from genes to proteins to complex networks within a cell and organism communities. The convergent knowledge of natural and engineered modular systems provides a key to drive modern biotechnology to address emergent challenges associated with health, food, energy, and the environment. Here, we first present the theory and application of modular design in traditional engineering fields. We then discuss the significance and impact of modular architectures on systems biology and biotechnology. Next, we focus on the very recent theoretical and experimental advances in modular cell engineering that seeks to enable rapid and systematic development of microbial catalysts capable of efficiently synthesizing a large space of useful chemicals. We conclude with an outlook towards theoretical and practical opportunities for a more systematic and effective application of modular cell engineering in biotechnology. 相似文献