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991.
992.
Payal Agarwal Melissa P. Crepps Natalie A. Stahr Will P. Kretzschmar Hannah C. Harris Nripesh Prasad Shawn E. Levy Bruce F. Smith 《Biochemistry and Biophysics Reports》2021
Delay in cancer diagnosis often results in metastasis and an inability to successfully treat the tumor. The use of broadly cancer-specific biomarkers at an early stage may improve cancer treatment and staging. This study has explored circulatory exosomal miRNAs as potential diagnostic biomarkers to identify cancer patients. Secretory exosomal miRNAs were isolated from 13 canine cancer cell lines (lymphoma, mast cell tumor, histiocytic cell line, osteosarcoma, melanoma, and breast tumor) and were sequenced by Next-Generation sequencing (NGS). We have identified 6 miRNAs (cfa-miR-9, -1841, ?1306, ?345, ?132, and ?26b) by NGS that were elevated in all cancer cell types. The miRNAs identified by NGS were then examined by Q-RT-PCR. The PCR data demonstrated similar expression patterns to those seen with NGS but provided fold differences that were much lower than those seen for NGS. Cfa-miR-9 was found to be the most consistently elevated miRNA in NGS and PCR, making it the most likely miRNA to prove diagnostic. In this study, we have demonstrated that it is possible to identify exosomal miRNAs with elevated secretion across multiple tumor types that could be used as circulatory diagnostic biomarkers for liquid biopsy in the future. 相似文献
993.
Modification of the degree of branching of a beta‐(1,3)‐glucan affects aggregation behavior and activity in an oxidative burst assay
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Andrew S. Magee Ryan R. Langeslay Paul M. Will Michael E. Danielson Lindsay R. Wurst Vanessa A. Iiams 《Biopolymers》2015,103(12):665-674
Scleroglucan is a β‐(1,3)‐glucan which is highly branched at the 6‐position with a single glucose residue. Acid hydrolysis of a high molecular weight scleroglucan gave a medium molecular weight, freely soluble material. Linkage analysis by the partially methylated alditol acetate method showed that the solubilized material had 30% branching. When the material was subjected to partial Smith degradations, the percent branching was reduced accordingly to 12% or 17%. After the percent branching was reduced, the average molecular weight of the samples increased considerably, indicating the assembly of higher ordered aggregate structures. An aggregate number distribution analysis was applied to confirm the higher aggregated structures. These aggregated structures gave the material significantly enhanced activity in an in vitro oxidative burst assay compared to the highly branched material. © 2015 Wiley Periodicals, Inc. Biopolymers 103: 665–674, 2015. 相似文献
994.
Invertebrate prey availability limits reproductive success but not breeding population size in suburban House Sparrows Passer domesticus
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Will J. Peach John W. Mallord Nancy Ockendon Chris J. Orsman William G. Haines 《Ibis》2015,157(3):601-613
Factors affecting avian demography and abundance in urban landscapes are poorly understood and this hinders attempts to manage urban bird communities. Several recent studies indicate that lack of invertebrate prey in urban landscapes may constrain avian productivity and fitness relative to that in other habitats. House Sparrow Passer domesticus populations have undergone large declines in many European urban centres and inadequate reproductive success linked to invertebrate availability has been postulated as a potential cause of these declines. We conducted a replicated supplementary feeding experiment to test whether the availability of invertebrate prey limits the breeding success and adult abundance (colony size) of House Sparrows in suburban London, where House Sparrow populations declined by 60% during the decade preceding our study. Daily mealworm provision over two successive breeding seasons, sufficient to provide 82% of chick energy requirements of House Sparrow pairs nesting within 50 m of feeders, had a large positive impact on the abundance of recently fledged birds (+62%), but only a small positive impact, limited mainly to small colonies, on the overall abundance of territorial males. Colony growth was only weakly related to fledgling abundance in the previous year and did not appear to be constrained by nest‐site availability. Conservation interventions that enhance invertebrate availability for suburban House Sparrows may increase reproductive success but are unlikely, on their own, to lead to population growth or recovery. 相似文献
995.
Romina Rader Will Edwards David A. Westcott Saul A. Cunningham Bradley G. Howlett 《Diversity & distributions》2011,17(3):519-529
Aim Dispersal distances of insect pollinators are critical in defining their contribution to landscape‐wide pollen movement and ultimately gene flow in natural and agricultural systems. We ask whether bee and fly pollinator taxa differ in their dispersal distances and transport of viable pollen in a human‐modified system. Location Canterbury and Otago region, South Island, New Zealand. Methods We captured pollen‐carrying insects travelling outside of a model mass‐flowering agricultural crop, Brassica rapa, using insect flight intercept traps at five distances (0, 100, 200, 300 and 400 m) from the pollen source. We examined pollen loads and pollen viability to determine whether pollen transport distance and viability differ among pollinator taxa. Results A total of 5453 insects were collected of which 717 individuals from 26 insect taxa were positively identified as dispersing pollen up to 400 m from the source. These taxa consisted of four species from two bee families (Hymenoptera: Apidae and Halictidae), and eight species from four fly families (Diptera: Bibiondae, Stratiomyidae, Syrphidae and Tachinidae). Apidae generally carried higher pollen loads and more viable pollen than most fly taxa. Taxa in the fly families Stratiomyidae and Syrphidae, however, carried pollen to 400 m, which is further than both bee families. Main conclusions A diverse array of wild and managed flower visitors can transport viable pollen from a pollen source to at least 400 m. Knowledge of the differences in transport distances among generalist pollinators in human‐modified environments is crucial to understand the potential extent to which (1) pollen transport can facilitate gene flow and (2) unwanted hybridization may occur between crops and related weeds. 相似文献
996.
The generic-level taxa included in Pterostichini and Loxandrini from New Caledonia are reviewed and a key to genera and species provided. Two new genera are described, Paniestichus and Abacophrastus, with the following new species: Paniestichus subsolianus, Abacophrastus millei, Abacophrastus chapes, Abacophrastus carnifex, Abacophrastus hobbit, Abacophrastus megalops, Abacophrastus reflexus and Abacophrastus bellorum. Abacoleptus curtus new species, is described. Notonomus irideus and Notonomus savesi are moved to Prosopogmus. Four new species of Prosopogmus are described: Prosopogmus koghisensis, Prosopogmus lescheni, Prosopogmus fortis and Prosopogmus aoupiniensis. Homalosoma griseolum is moved to Sphodrosomus. Cerabilia is newly recorded from New Caledonia and the genus is moved from Platynini to Loxandrini and therefore is the first report of Loxandrini from New Caledonia. An apparent adventive from Australia, Darodilia, is newly reported from New Caledonia. 相似文献
997.
Microbial metagenomes derived from soils are rich sources for the discovery of novel genes and biocatalysts. Fourteen environmental plasmid and seven fosmid libraries obtained from 10 German forest soils (A horizons) and six grassland soils (A and B horizons) were screened for genes conferring lipolytic activity. The libraries comprised approximately 29.3 Gb of cloned soil DNA. Partial activity-based screening of the constructed libraries resulted in the identification of 37 unique lipolytic clones. The amino acid sequences of the 37 corresponding lipolytic gene products shared 29-90% identity to other lipolytic enzymes, which were mainly uncharacterized or derived from uncultured microorganisms. Multiple sequence alignments and phylogenetic tree analysis revealed that 35 of the predicted proteins were new members of known families of lipolytic enzymes. The remaining two gene products represent two putatively new families. In addition, sequence analysis indicated that two genes encode true lipases, whereas the other genes encode esterases. The determination of substrate specificity and chain-length selectivity using different triacylglycerides and p-nitrophenyl esters of fatty acids as substrates supported the classification of the esterases. 相似文献
998.
Steinbusch LK Luiken JJ Vlasblom R Chabowski A Hoebers NT Coumans WA Vroegrijk IO Voshol PJ Ouwens DM Glatz JF Diamant M 《American journal of physiology. Endocrinology and metabolism》2011,301(4):E618-E627
Cardiac patients often are obese and have hypertension, but in most studies these conditions are investigated separately. Here, we aimed at 1) elucidating the interaction of metabolic and mechanophysical stress in the development of cardiac dysfunction in mice and 2) preventing this interaction by ablation of the fatty acid transporter CD36. Male wild-type (WT) C57Bl/6 mice and CD36(-/-) mice received chow or Western-type diet (WTD) for 10 wk and then underwent a sham surgery or transverse aortic constriction (TAC) under anesthesia. After a 6-wk continuation of the diet, cardiac function, morphology, lipid profiles, and molecular parameters were assessed. WTD administration affected body and organ weights of WT and CD36(-/-) mice, but it affected only plasma glucose and insulin concentrations in WT mice. Cardiac lipid concentrations increased in WT mice receiving WTD, decreased in CD36(-/-) on chow, and remained unchanged in CD36(-/-) receiving WTD. TAC induced cardiac hypertrophy in WT mice on chow but did not affect cardiac function and cardiac lipid concentrations. WTD or CD36 ablation worsened the outcome of TAC. Ablation of CD36 protected against the WTD-related aggravation of cardiac functional and structural changes induced by TAC. In conclusion, cardiac dysfunction and remodeling worsen when the heart is exposed to two stresses, metabolic and mechanophysical, at the same time. CD36 ablation prevents the metabolic stress resulting from a WTD. Thus, metabolic conditions are a critical factor for the compromised heart and provide new targets for metabolic manipulation in cardioprotection. 相似文献
999.
Bacteria of Bacillus species sporulate upon starvation, and the resultant dormant spores germinate when the environment appears likely to allow the resumption of vegetative growth. Normally, the rates of germination of individual spores in populations are very heterogeneous, and the current work has investigated whether spore-to-spore communication enhances the synchronicity of germination. In order to do this work, time-lapse optical images of thousands of individual spores were captured during germination, and an image analysis algorithm was developed to do the following: (i) measure the positions and germination rates of many thousands of individual spores and (ii) compute pairwise correlations of their germination. This analysis showed that an individual spore''s germination rate was dependent on its distance from other spores, especially at short distances. Thus, spores that were within a few micrometers exhibited an increased synchronicity in germination, suggesting that there is a mechanism for short-range communication between such spores during germination. However, two molecules known to be germinants that are released during germination, l-alanine and the 1:1 chelate of Ca2+ and dipicolinic acid, did not mediate spore-to-spore communication during germination. 相似文献
1000.