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181.
Zeynep Eroglu Sheri L. Holmen Qing Chen Nikhil I. Khushalani Ravi Amaravadi Reena Thomas Kamran A. Ahmed Hussein Tawbi Sunandana Chandra Joseph Markowitz Inna Smalley James K. C. Liu Yian Ann Chen Yana G. Najjar Florian A. Karreth Daniel Abate‐Daga Isabella C. Glitza Jeffrey A. Sosman Vernon K. Sondak Marcus Bosenberg Meenhard Herlyn Michael B. Atkins Harriet Kluger Kim Margolin Peter A. Forsyth Michael A. Davies Keiran S. M. Smalley 《Pigment cell & melanoma research》2019,32(3):458-469
In February 2018, the Melanoma Research Foundation and the Moffitt Cancer Center hosted the Second Summit on Melanoma Central Nervous System (CNS) Metastases in Tampa, Florida. In this white paper, we outline the current status of basic science, translational, and clinical research into melanoma brain metastasis development and therapeutic management. We further outline the important challenges that remain for the field and the critical barriers that need to be overcome for continued progress to be made in this clinically difficult area. 相似文献
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Chengfeng Le Shuyu Wu Chuanmin Hu Marcus W. Beck Xuchao Yang 《Global Change Biology》2019,25(10):3485-3493
Global climate change can significantly influence oceanic phytoplankton dynamics, and thus biogeochemical cycles and marine food webs. However, associative explanations based on the correlation between chlorophyll‐a concentration (Chl‐a) and climatic indices is inadequate to describe the mechanism of the connection between climate change, large‐scale atmospheric dynamics, and phytoplankton variability. Here, by analyzing multiple satellite observations of Chl‐a and atmospheric conditions from National Center for Environmental Prediction/National Center for Atmospheric Research reanalysis datasets, we show that high‐latitude atmospheric blocking events over Alaska are the primary drivers of the recent decline of Chl‐a in the eastern North Pacific transition zone. These blocking events were associated with the persistence of large‐scale atmosphere pressure fields that decreased westerly winds and southward Ekman transport over the subarctic ocean gyre. Reduced southward Ekman transport leads to reductions in nutrient availability to phytoplankton in the transition zone. The findings describe a previously unidentified climatic factor that contributed to the recent decline of phytoplankton in this region and propose a mechanism of the top‐down teleconnection between the high‐latitude atmospheric circulation anomalies and the subtropical oceanic primary productivity. The results also highlight the importance of understanding teleconnection among atmosphere–ocean interactions as a means to anticipate future climate change impacts on oceanic primary production. 相似文献
186.
Philip A. Stephens Marcus V. Vieira Stephen G. Willis Chris Carbone 《Ecology letters》2019,22(4):654-663
We address two fundamental ecological questions: what are the limits to animal population density and what determines those limits? We develop simple alternative models to predict population limits in relation to body mass. A model assuming that within‐species area use increases with the square of daily travel distance broadly predicts the scaling of empirical extremes of minimum density across birds and mammals. Consistent with model predictions, the estimated density range for a given mass, ‘population scope’, is greater for birds than for mammals. However, unlike mammals and carnivorous birds, expected broad relationships between body mass and density extremes are not supported by data on herbivorous and omnivorous birds. Our results suggest that simple constraints on mobility and energy use/supply are major determinants of the scaling of density limits, but further understanding of interactions between dietary constraints and density limits are needed to predict future wildlife population responses to anthropogenic threats. 相似文献
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Colin Creighton Vishnu N. Prahalad Ian McLeod Marcus Sheaves Matthew D. Taylor Terry Walshe 《Ecological Management & Restoration》2019,20(3):182-191
Three case studies spanning tropical, subtropical and temperate environments highlight the minimum potential benefits of investing in repair of coastal seascapes. Fisheries, a market benefit indicator readily understood by a range of stakeholders from policymakers to community advocates, were used as a surrogate for ecosystem services generated through seascape habitat restoration. For each case study, while recognising that biological information will always remain imperfect, the prospects for seascape repair are compelling. 相似文献
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Lílian Cardoso de Paiva Raphael Hermano Santos Diniz Pedro Marcus Pereira Vidigal Tiago Antônio de Oliveira Mendes Mateus Ferreira Santana María-Esperanza Cerdán María-Isabel González-Siso Wendel Batista da Silveira 《Fungal biology》2019,123(9):687-697
Kluyveromyces marxianus CCT 7735 has been used to produce ethanol, aromatic compounds, enzymes and heterologous proteins besides assimilates lactose as carbon source. Its genome has 10.7 Mb and encodes 4787 genes distributed in 8 nuclear chromosomes and one mitochondrial. Contrary to Kluyveromyces lactis, which has a unique LAC12 gene (encodes lactose permease), K. marxianus possesses four. The presence of degenerated copies and Solo-LTRs related to retrotransposon TKM close to the LAC12 genes in K. marxianus indicates ectopic recombinations. The Lac12 permeases of K. marxianus and K. lactis are conserved, however the conservation is higher between the copy of the left side of the chromosome three and the unique copy of K. lactis, indicating that this copy is the ancestor. The expression of the four LAC12 genes occurred in aerobiosis and hypoxia. Notably, the high lactose consumption in hypoxia seems to be related to the high expression of the LAC12 genes. 相似文献
189.
Corrêa Soares JB Maya-Monteiro CM Bittencourt-Cunha PR Atella GC Lara FA d'Avila JC Menezes D Vannier-Santos MA Oliveira PL Egan TJ Oliveira MF 《FEBS letters》2007,581(9):1742-1750
Hemozoin (Hz) is a heme crystal produced upon hemoglobin digestion as the main mechanism of heme disposal in several hematophagous organisms. Here, we show that, in the helminth Schistosoma mansoni, Hz formation occurs in extracellular lipid droplets (LDs). Transmission electron microscopy of adult worms revealed the presence of numerous electron-lucent round structures similar to LDs in gut lumen, where multicrystalline Hz assemblies were found associated to their surfaces. Female regurgitates promoted Hz formation in vitro in reactions partially inhibited by boiling. Fractionation of regurgitates showed that Hz crystallization activity was essentially concentrated on lower density fractions, which have small amounts of pre-formed Hz crystals, suggesting that hydrophilic-hydrophobic interfaces, and not Hz itself, play a key catalytic role in Hz formation in S. mansoni. Thus, these data demonstrate that LDs present in the gut lumen of S. mansoni support Hz formation possibly by allowing association of heme to the lipid-water interface of these structures. 相似文献
190.
Considerable effort has been invested in determining traits underlying invasiveness. Yet, identifying a set of traits that
commonly confers invasiveness in a range of species has proven elusive, and almost nothing is known about genetic loci affecting
invasive success. Incorporating genetic model organisms into ecologically relevant studies is one promising avenue to begin
dissecting the genetic underpinnings of invasiveness. Molecular biologists are rapidly characterizing genes mediating developmental
responses to diverse environmental cues, i.e., genes for plasticity, as well as to environmental factors likely to impose
strong selection on invading species, e.g., resistance to herbivores and competitors, coordination of life-history events
with seasonal changes, and physiological tolerance of heat, drought, or cold. Here, we give an overview of molecular genetic
tools increasingly used to characterize the genetic basis of adaptation and that may be used to begin identifying genetic
mechanisms of invasiveness. Given the divergent traits that affect invasiveness, “invasiveness genes” common to many clades
are unlikely, but the combination of developmental genetic advances with further evolutionary studies and modeling may provide
a framework for identifying genes that account for invasiveness in related species. 相似文献