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排序方式: 共有651条查询结果,搜索用时 15 毫秒
1.
Spliceosome-targeted therapies trigger an antiviral immune response in triple-negative breast cancer
Elizabeth A. Bowling Jarey H. Wang Fade Gong William Wu Nicholas J. Neill Ik Sun Kim Siddhartha Tyagi Mayra Orellana Sarah J. Kurley Rocio Dominguez-Vidaña Hsiang-Ching Chung Tiffany Y.-T. Hsu Julien Dubrulle Alexander B. Saltzman Heyuan Li Jitendra K. Meena Gino M. Canlas Srinivas Chamakuri Thomas F. Westbrook 《Cell》2021,184(2):384-403.e21
2.
Interactions among species with contrasting dispersal modes explain distributions for epiphytic lichens 下载免费PDF全文
Understanding how the biodiversity response to climate change will be modified at ecological scales, e.g. by species interactions, is a major challenge. Lichen epiphytes – the close interdependent relationship between a heterotrophic fungus and photosynthetic partner (photobiont) – are used here to explore how interaction regimes (between lichen species, and between lichens and their photobionts) explain distribution patterns along spatial climatic gradients. To do this we tested field evidence for the ‘core‐fringe hypothesis’, which proposes a facilitative interaction; sexually‐reproducing and spore‐dispersed lichens with a requirement for resynthesis with a compatible photobiont (Nostoc) are facilitated by the prior establishment of asexual lichens which disperse both the fungus and photobiont together. We used two closely related Nephroma species which differ in their reproductive mode – N. laevigatum (sexual spore‐dispersed) and N. parile (asexual) – and compared their occurrence along a bioclimatic gradient to local habitat factors, including the co‐occurrence of asexual lichens which have shared specificity for compatible Nostoc genotypes. The results showed that: 1) N. laevigatum is significantly more likely to occur on trees that have already been colonised by asexual lichens with shared specificity for Nostoc, supporting the core‐fringe hypothesis, while 2) N. parile is independent of this association (strengthening the core‐fringe hypothesis), with its response to a precipitation gradient modified by microhabitat factors. This positive test for the core‐fringe hypothesis demonstrates how interaction regimes can fundamentally alter expectations under climate change. There is an assumption that spore‐dispersed lichen species could more easily track their suitable bioclimatic space through fragmented habitat, compared to asexual species with larger and heavier propagules. However, the establishment of spore‐dispersed lichen epiphytes into new habitat may be limited by the dispersal rates of asexual species, which act as key facilitators. 相似文献
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M. Mar Díaz-Herrero José A. del Campo Pilar Carbonero-Aguilar José M. Vega-Pérez Fernando Iglesias-Guerra Ignacio Peri?án Francisco J. Mi?ano Juan Bautista Manuel Romero-Gómez 《PloS one》2014,9(10)
Ammonia production is implicated in the pathogenesis of hepatic encephalopathy (HE), being intestinal glutaminase activity the main source for ammonia. Management of ammonia formation can be effective in HE treatment by lowering intestinal ammonia production. The use of glutaminase inhibitors represents one way to achieve this goal. In this work, we have performed a search for specific inhibitors that could decrease glutaminase activity by screening two different groups of compounds: i) a group integrated by a diverse, highly pure small molecule compounds derived from thiourea ranging from 200 to 800 Daltons; and ii) a group integrated by commonly use compounds in the treatment of HE. Results shown that THDP-17 (10 µM), a thiourea derivate product, could inhibit the intestinal glutaminase activity (57.4±6.7%). Inhibitory effect was tissue dependent, ranging from 40±5.5% to 80±7.8% in an uncompetitive manner, showing Vmax and Km values of 384.62 µmol min−1, 13.62 mM with THDP-17 10 µM, respectively. This compound also decreased the glutaminase activity in Caco-2 cell cultures, showing a reduction of ammonia and glutamate production, compared to control cultures. Therefore, the THDP-17 compound could be a good candidate for HE management, by lowering ammonia production. 相似文献
5.
The aim of the article is to develop and explore the idea that soil health is an essential element in combating climate change and promoting food security. An important aspect of this is that soil, rather than simply serving to support plants and as a niche for animals and microbes, also functions as a natural reactor that, through a series of chemical and biological reactions, purifies water, replenish aquifers and maintains equilibria in surface waters. This topic is particularly timely given the recent announcement of the Mission program for Health of Soils by the European Commission. Within this realm, the article intends to catalyze and promote the debate around what defines sustainable agriculture in order to help shape its future. 相似文献
6.
Ecosystems - Identified as essential mechanisms promoting alternative stable states, positive feedbacks have been the focus of most former studies on the potential for catastrophic shifts in... 相似文献
7.
Guilherme Rocha Melo Gondim Fabiana Baroni Alves Makdissi Ricardo Cesar Fogaroli Juan Bautista Donoso Collins Hirofumi Iyeyasu Douglas Guedes de Castro Maria Letícia Gobo Silva Michael Jenwei Chen Tharcisio Machado Coelho Henderson Ramos Antônio Cássio Assis Pellizzon 《Reports of Practical Oncology and Radiotherapy》2019,24(6):551-555
BackgroundWhole breast irradiation reduces loco-regional recurrence and risk of death in patients submitted to breast-conserving treatment. Data show that radiation to the index quadrant alone may be enough in selected patients.AimTo report the experience with intra-operative radiotherapy (IORT) with Electron-beam Cone in Linear Accelerator (ELIOT) and the results in overall survival, local control and late toxicity of patients submitted to this treatment.Materials and Methods147 patients treated with a median follow up of 6.9 years (0.1?11.5 years). The actuarial local control and overall survival probabilities were estimated using the Kaplan Meier method. All tests were two-sided and p ? 0.05 was considered statistically significant.ResultsOverall survival of the cohort in 5 years, in the median follow up and in 10 years was of 98.3%, 95.1% and 95.1%, respectively, whereas local control in 5 years, in the median follow up and in 10 years was of 96%, 94.9% and 89.5%, respectively. Two risk groups were identified for local recurrence depending on the estrogen or progesterone receptors, axillary or margin status and lymphovascular invasion (LVI) (p = 0.016).ConclusionsIORT is a safe and effective treatment. Rigorous selection is important to achieve excellent local control results. 相似文献
8.
Daniel J. Burkett Brittney N. Wyatt Mallory Mews Anson Bautista Ryan Engel Chris Dockendorff William A. Donaldson Martin St. Maurice 《Bioorganic & medicinal chemistry》2019,27(18):4041-4047
Through a structure-based drug design project (SBDD), potent small molecule inhibitors of pyruvate carboxylase (PC) have been discovered. A series of α-keto acids (7) and α-hydroxycinnamic acids (8) were prepared and evaluated for inhibition of PC in two assays. The two most potent inhibitors were 3,3′-(1,4-phenylene)bis[2-hydroxy-2-propenoic acid] (8u) and 2-hydroxy-3-(quinoline-2-yl)propenoic acid (8v) with IC50 values of 3.0 ± 1.0 μM and 4.3 ± 1.5 μM respectively. Compound 8v is a competitive inhibitor with respect to pyruvate (Ki = 0.74 μM) and a mixed-type inhibitor with respect to ATP, indicating that it targets the unique carboxyltransferase (CT) domain of PC. Furthermore, compound 8v does not significantly inhibit human carbonic anhydrase II, matrix metalloproteinase-2, malate dehydrogenase or lactate dehydrogenase. 相似文献
9.
Jeimy D. Santiago‐Valentín Alma P. Rodríguez‐Troncoso Eric Bautista‐Guerrero Andrs Lpez‐Prez Amilcar L. Cupul‐Magaa 《Invertebrate Biology》2019,138(1):29-39
Porites panamensis is a hermatypic brooder coral endemic to, and distributed along, the Eastern Tropical Pacific, and is considered a species vulnerable to local effects because it has limited capacity for long‐distance dispersal (and low genetic diversity). Although larvae of P. panamensis have been previously shown to recruit to artificial settlement platforms, they have never been observed in the water column. The present study describes the reproductive behavior of P. panamensis, with a focus on using molecular tools to document evidence for a larval planktonic stage and for successful recruitment. Larvae collected from the water column, and recruitment on natural and artificial substrata were documented. Phylogenetic analysis of two ribosomal markers, 18s rRNA and ITS (ITS1‐5.8‐ITS2), and one mitochondrial marker, cytochrome oxidase subunit 1 (cox1), confirmed the taxonomic identity of larvae, and showed that larvae and recruits have genotypes similar to adults of P. panamensis. Lipid vacuoles and Symbiodinium sp. were present in the gastrodermis of all larvae. A total of 12 and 371 recruits settled on artificial and natural substrates, respectively, and the recruitment rate differed significantly over time. By documenting the reproductive success of the species, we show the potential for existing individuals both to maintain the population in the study area and to contribute to maintenance of the coral reef community in the coming decades. 相似文献
10.
Geraldine Ladino Fabiola Ospina‐Bautista Jaime Estvez Varn Lucie Jerabkova Pavel Kratina 《Ecology and evolution》2019,9(12):7360-7372
The unprecedented loss of biological diversity has negative impacts on ecosystems and the associated benefits which they provide to humans. Bromeliads have high diversity throughout the Neotropics, but they have been negatively affected by habitat loss and fragmentation, climate change, invasive species, and commercialization for ornamental purpose. These plants provide direct benefits to the human society, and they also form microecosystems in which accumulated water and nutrients support the communities of aquatic and terrestrial species, thus maintaining local diversity. We performed a systematic review of the contribution of bromeliads to ecosystem services across their native geographical distribution. We showed that bromeliads provide a range of ecosystem services such as maintenance of biodiversity, community structure, nutrient cycling, and the provisioning of food and water. Moreover, bromeliads can regulate the spread of diseases, and water and carbon cycling, and they have the potential to become important sources of chemical and pharmaceutical products. The majority of this research was performed in Brazil, but future research from other Neotropical countries with a high diversity of bromeliads would fill the current knowledge gaps and increase the generality of these findings. This systematic review identified that future research should focus on provisioning, regulating, and cultural services that have been currently overlooked. This would enhance our understanding of how bromeliad diversity contributes to human welfare, and the negative consequences that loss of bromeliad plants can have on communities of other species and the healthy functioning of the entire ecosystems. 相似文献