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91.
Rmi Cousin Hugo Groult Chanez Manseur Romain Ferru-Clment Mario Gani Rachel Havret Claire Toucheteau Grgoire Prunier Batrice Colin Franck Morel Jean-Marie Piot Isabelle Lanneluc Kvin Baranger Thierry Maugard Ingrid Fruitier-Arnaudin 《Marine drugs》2021,19(10)
Sugar-based molecules such as heparins or natural heparan sulfate polysaccharides have been developed and widely studied for controlling heparanase (HPSE) enzymatic activity, a key player in extracellular matrix remodelling during cancer pathogenesis. However, non-enzymatic functions of HPSE have also been described in tumour mechanisms. Given their versatile properties, we hypothesized that sugar-based inhibitors may interfere with enzymatic but also non-enzymatic HPSE activities. In this work, we assessed the effects of an original marine λ-carrageenan derived oligosaccharide (λ-CO) we previously described, along with those of its native counterpart and heparins, on cell viability, proliferation, migration, and invasion of MDA-MB-231 breast cancer cells but also of sh-MDA-MB-231 cells, in which the expression of HPSE was selectively downregulated. We observed no cytotoxic and no anti-proliferative effects of our compounds but surprisingly λ-CO was the most efficient to reduce cell migration and invasion compared with heparins, and in a HPSE-dependent manner. We provided evidence that λ-CO tightly controlled a HPSE/MMP-14/MMP-2 axis, leading to reduced MMP-2 activity. Altogether, this study highlights λ-CO as a potent HPSE “modulator” capable of reducing not only the enzymatic activity of HPSE but also the functions controlled by the HPSE levels. 相似文献
92.
Density‐ and species‐dependent errors in single‐pass timed electrofishing assessment of riverine salmonids 下载免费PDF全文
Hannele M. Honkanen Jennifer A. Dodd Jessica R. Fordyce Patrick Boylan Colin E. Adams 《Ecology of Freshwater Fish》2018,27(1):98-102
Electrofishing techniques are widely used for the estimation of the size of stream‐dwelling fish populations for both fishery management and scientific study. In contrast to multiple pass, population depletion methods, single‐pass catch‐per‐unit‐effort (CPUE) methods are less time‐consuming and labour‐intensive. A possible issue with the commonly used fixed total time CPUE protocol is that it does not differentiate between the time spent actively fishing and the time incurred while not actively fishing (e.g. removing fish from nets and navigating the site). This issue is likely related to fish density. This study compared two methods of CPUE electrofishing and tested the hypothesis that time spent handling fish and navigating a site can be a source of error in the commonly used fixed total time electrofishing method. Seventy‐one sites were sampled across three subcatchments in the Foyle catchment in Northern Ireland. We found a difference in the catch per unit time between the two methods and that this difference increased with fish density. The fixed‐time CPUE method also failed to detect a species presence in low‐density sites. 相似文献
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Alexander M. Stuart Colin V. PrescottGrant R. Singleton Ravindra C. Joshi 《Crop Protection》2011,30(2):147-154
A survey of the knowledge, attitudes and practices (KAP) of 100 rice farmers and 50 coconut farmers was conducted in the coastal lowland agro-ecosystems of the Sierra Madre Biodiversity Corridor, Luzon, Philippines to identify current rodent management practices and to understand the extent of rat damage and the attitudes of farmers to community actions for rodent management. Pests were most commonly listed as one of the three most important rice and coconut production constraints. Other major crop production constraints were typhoons and insufficient water. Farmers consider rats to be the major pest of coconut and of rice during the wet season rice crop, with average yield losses of 3.0% and 13.2%, respectively. Rice and coconut farmers practised a wide range of rodent management techniques. These included scrub clearance, hunting and trapping. Of the 42 rice farmers and 3 coconut farmers that applied rodenticides to control rodents, all used the acute rodenticide, zinc phosphide. However, only ten rice farmers (23.8%) applied rodenticides prior to the booting stage and only seven farmers (15.6%) conducted pre-baiting before applying zinc phosphide. The majority of farmers belonged to farmer organisations and believed that rat control can only be done by farmers working together. However, during the last cropping season, less than a third of rice farmers (31.2%) applied rodent management as a group. In order to reduce the impact of rodents on the farmers of the coastal lowlands of the Sierra Madre Biodiversity Corridor, integrated management strategies need to be developed that specifically target the pest rodents in a sustainable manner, and community actions for rodent management should be promoted. 相似文献
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Verónica Leticia Colin Natalia Bourguignon Johana Stefi Gómez Kátia Gianni de Carvalho Marcela Alejandra Ferrero María Julia Amoroso 《Water, air, and soil pollution》2017,228(12):454
The replacement of synthetic surface-active compounds (SACs) by their microbial counterparts is carving out a niche for themselves in the field of bioremediation. However, the high cost of microbial products has limited their application at a realistic scale. In the current study, several hydrocarbon-degrading microorganisms were assayed as potential SAC producers in low-cost liquid media. Only the strain CC10, placed within the class Actinobacteria, was able to produce emulsifying molecules by using a combination of sugarcane vinasse or crude glycerol (as cheap carbon substrates) with urea or peptone (as nitrogen sources). The emulsifying activity of the supernatants and the stability of emulsions formed with motor oil depended on the carbon and nitrogen sources. However, the biodegradability of these metabolites was only associated with the carbon substrate, and it was always higher than the two tested synthetic surfactants, sodium dodecyl sulfate and Triton X-100. Also, a positive linear association between emulsifying and lipase activities of the CC10 supernatants was detected (r?=?0.781; p?=?0.219), with the maximum activities detected in the glycerol-peptone supernatant. Interestingly, this supernatant was able to emulsify different oily substrates, a property that could be used to increase the efficiency of the treatment of effluents with high fat content. 相似文献
98.
Colin F Quinn John L Freeman Ray JB Reynolds Jennifer J Cappa Sirine C Fakra Matthew A Marcus Stormy D Lindblom Erin K Quinn Lindsay E Bennett Elizabeth AH Pilon-Smits 《BMC ecology》2010,10(1):19
Background
Hyperaccumulation, the rare capacity of certain plant species to accumulate toxic trace elements to levels several orders of magnitude higher than other species growing on the same site, is thought to be an elemental defense mechanism against herbivores and pathogens. Previous research has shown that selenium (Se) hyperaccumulation protects plants from a variety of herbivores and pathogens. Selenium hyperaccumulating plants sequester Se in discrete locations in the leaf periphery, making them potentially more susceptible to some herbivore feeding modes than others. In this study we investigate the protective function of Se in the Se hyperaccumulators Stanleya pinnata and Astragalus bisulcatus against two cell disrupting herbivores, the western flower thrips (Frankliniella occidentalis) and the two-spotted spider mite (Tetranychus urticae). 相似文献99.
The emergence of canine parvovirus (CPV) represents a well-documented example highlighting the emergence of a new virus through cross-species transmission. CPV emerged in the mid-1970s as a new pathogen of dogs and has since become endemic in the global dog population. Despite widespread vaccination, CPV has remained a widespread disease of dogs, and new genetic and antigenic variants have arisen and sometimes reached high frequency in certain geographic regions or throughout the world. Here we review our understanding of this emergence event and contrast it to what is known about the emergence of a disease in mink caused by mink enteritis virus (MEV). In addition, we summarize the evolution of CPV over the past 30 years in the global dog population, and describe the epidemiology of contemporary parvovirus infections of dogs and cats. CPV represents a valuable model for understanding disease emergence through cross-species transmission, while MEV provides an interesting comparison. 相似文献
100.
Carl R. Gosper Suzanne M. Prober Colin J. Yates 《Strength and Conditioning Journal》2010,63(5):588-592
Prescribed fire and/or mechanical methods can be used to modify the quantity, continuity, and/or spatial arrangement of flammable fuel. Yet the consequences of fuel management, both in terms of ecological outcomes and in facilitating improved fire management, often are poorly documented. In the global biodiversity hotspot of southwest Western Australia, chaining and burning is a novel technique for manipulating fuels. Vegetation first is dislodged using a chain, then after a period of curing, burnt. We tested whether combining two disturbance events in this way results in different vegetation structure postfire than only burning, and whether the postfire sprouting capacity of community-dominant Eucalyptus spp. is compromised. Both chained and burnt and only burnt treatments had much less leaf litter and vegetation > 25 cm high than long-unburnt vegetation, indicating a fire management benefit of fuel modification. Chained and burnt strips had a threefold reduction in standing dead vegetation compared to only burnt samples. The stem number of Eucalyptus spp. was reduced by 20% in chained and burnt strips compared to only burnt vegetation, indicating that consecutive disturbances reduce resilience and might render sprouters vulnerable to subsequent disturbances. Balancing the fire management benefits of chaining and burning with the ecological consequences is a significant challenge facing land managers in this fire-prone landscape. 相似文献