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1.
Benjamin C. Blum Weiwei Lin Matthew L. Lawton Qian Liu Julian Kwan Isabella Turcinovic Ryan Hekman Pingzhao Hu Andrew Emili 《Molecular & cellular proteomics : MCP》2022,21(1):100189
Metabolism is recognized as an important driver of cancer progression and other complex diseases, but global metabolite profiling remains a challenge. Protein expression profiling is often a poor proxy since existing pathway enrichment models provide an incomplete mapping between the proteome and metabolism. To overcome these gaps, we introduce multiomic metabolic enrichment network analysis (MOMENTA), an integrative multiomic data analysis framework for more accurately deducing metabolic pathway changes from proteomics data alone in a gene set analysis context by leveraging protein interaction networks to extend annotated metabolic models. We apply MOMENTA to proteomic data from diverse cancer cell lines and human tumors to demonstrate its utility at revealing variation in metabolic pathway activity across cancer types, which we verify using independent metabolomics measurements. The novel metabolic networks we uncover in breast cancer and other tumors are linked to clinical outcomes, underscoring the pathophysiological relevance of the findings. 相似文献
2.
Lucas Henriques Viscardi Danilo Oliveira Imparato Maria Ctira Bortolini Rodrigo Juliani Siqueira Dalmolin 《Molecular biology and evolution》2021,38(3):735
The origin of nervous systems is a main theme in biology and its mechanisms are largely underlied by synaptic neurotransmission. One problem to explain synapse establishment is that synaptic orthologs are present in multiple aneural organisms. We questioned how the interactions among these elements evolved and to what extent it relates to our understanding of the nervous systems complexity. We identified the human neurotransmission gene network based on genes present in GABAergic, glutamatergic, serotonergic, dopaminergic, and cholinergic systems. The network comprises 321 human genes, 83 of which act exclusively in the nervous system. We reconstructed the evolutionary scenario of synapse emergence by looking for synaptic orthologs in 476 eukaryotes. The Human–Cnidaria common ancestor displayed a massive emergence of neuroexclusive genes, mainly ionotropic receptors, which might have been crucial to the evolution of synapses. Very few synaptic genes had their origin after the Human–Cnidaria common ancestor. We also identified a higher abundance of synaptic proteins in vertebrates, which suggests an increase in the synaptic network complexity of those organisms. 相似文献
3.
Fish finders have already been widely available in the fishing market for a number of years.However,the sizes of these fishfinders are too big and their prices are expensive to suit for the research of robotic fish or mini-submarine.The goal of thisresearch is to propose a low-cost fish detector and classifier which suits for underwater robot or submarine as a proximity sensor.With some pre-condition in hardware and algorithms,the experimental results show that the proposed design has good per-formance,with a detection rate of 100 % and a classification rate of 94 %.Both the existing type of fish and the group behaviorcan be revealed by statistical interpretations such as hovering passion and sparse swimming mode. 相似文献
4.
Abstract The stability of clathrate hydrates encaging highly polar guests has been investigated in order to explain the experimental observation that some amines form clathrate hydrates but alcohols act as inhibitor to hydrate formation. We choose methylamine and methanol as guest species and examine the stable structure, at which the total potential energy has a minimum value. At the local minima of those two hydrates, the potential energies of water-water and guest-water, and their hydrogen bonded networks are compared. It is found that methanol does not retain the host lattice structure, while the host-network structure is kept in the presence of methylamine. It is shown that the difference in the magnitude of the partial charge on the hydrogen atom between the hydroxyl and amino groups plays a much more significant role on the stability of both clathrate hydrates than the difference in molecular geometry. This is supported from the result of a methylamine-like model that has the same partial charges on the atoms in the hydrophilic site as methanol. 相似文献
5.
In the flower of Hydrolea palustris, unusually orientated with one sepal abaxially, organogenesis starts in following sequence: five sepals (2/5 sequence), five simultaneously initiated alternating petals, five episepalous stamens, two (seldom three) carpels forming a coenocarpous septate gynoecium. The two carpels are orientated rather in the diagonal floral plane than in the median one. Petal primordia fuse very late by forming interprimordial bridges (late sympetaly!). Many ovules develop on considerably widened placentas. On the very basis of the superior ovary a five-humped nectary disk is formed.Within Solanales (APG II 2003) late sympetaly, an intrastaminal disk and a 2-carpellate, septate, superior ovary are found in Hydroleaceae, Convolvulaceae, and Solanaceae. Enlarged axile placentas characterize Hydrolea, Solanaceae, and Sphenocleaceae but Sphenocleaceae differ considerably by early sympetaly. Montiniaceae differ by having a choripetalous corolla. Nearly diagonal orientation of the carpels seems to relate Hydrolea close to Solanaceae, but the orientation of the calyx is different. 相似文献
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7.
Makoto Tajima Nobuko Sekiguchi Masao Fujimaki 《Bioscience, biotechnology, and biochemistry》2013,77(2):319-320
High phosphate accumulating bacteria were isolated by autoradiography. One isoate, Arthrobacter globiformis PAB-6 accumulated phosphate intracellularly at 20% of dry cell mass in a simple synthetic medium. This amount was 3~7 times higher than type cultures examined. Almost no phosphate was released into the medium after cessation of growth. Fifty percent of total intracellular phosphate was fractionated as nucleic acids, while 20% each was recovered from cold PCA soluble fractions and polyphosphate fractions. The large content of nucleic acids in this bacterium appeared due to increased RNA content, specifically 4 S RNA fraction. 相似文献
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9.
Janitha A. Liyanage David M. Taylor David R. Williams 《Chemical Speciation and Bioavailability》2013,25(2):73-75
ABSTRACTA method has been developed for impregnating alginate-based wound dressings with trace elements required for wound healing and for quantifying the transfer from these dressing to wound fluid (for which a substitute—blood serum—was used in these experiments). Under ideal conditions, up to 85% can be carried across from the tow to the wound fluid. 相似文献
10.
G. Ballantyne Katherine C. R. Baldock P. G. Willmer 《Proceedings. Biological sciences / The Royal Society》2015,282(1814)
Interaction networks are widely used as tools to understand plant–pollinator communities, and to examine potential threats to plant diversity and food security if the ecosystem service provided by pollinating animals declines. However, most networks to date are based on recording visits to flowers, rather than recording clearly defined effective pollination events. Here we provide the first networks that explicitly incorporate measures of pollinator effectiveness (PE) from pollen deposition on stigmas per visit, and pollinator importance (PI) as the product of PE and visit frequency. These more informative networks, here produced for a low diversity heathland habitat, reveal that plant–pollinator interactions are more specialized than shown in most previous studies. At the studied site, the specialization index was lower for the visitation network than the PE network, which was in turn lower than for the PI network. Our study shows that collecting PE data is feasible for community-level studies in low diversity communities and that including information about PE can change the structure of interaction networks. This could have important consequences for our understanding of threats to pollination systems. 相似文献