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  • 文章类型: Journal Article
    塑料的广泛使用导致了各种尺寸的塑料废物的积累,特别是包括微塑料(MP)。将MPs引入水生生态系统可能导致生物体的污染,主要是鱼。这项研究首次对Gresik的乳鱼养殖池塘的水和沉积物中遇到的MPs的丰度进行了定量和定性分析,东爪哇,印度尼西亚。在2021年2月至4月之间在三个站点收集了水和沉积物样本。应用单因素方差分析和Pearson相关分析对MPs的丰度进行分析。结果确定了四种类型的MP:碎片,纤维,电影,和颗粒。3月观察到水(10.40颗粒/L)和沉积物样品(1.15颗粒/g)中MPs的最高丰度。水样中主要的MPs大小为100-500μm,而在沉积物中低于100μm。国会议员的颜色有八种不同的颜色:黑色,紫色,红色,蓝色,黄色,粉色,绿色,和透明。MPs聚合物的鉴定被发现是聚丙烯(PP),聚氨酯(PU),聚碳酸酯(PC),聚对苯二甲酸乙二醇酯(PETE),高密度聚乙烯(HDPE),和低密度聚乙烯(LDPE)。水柱和沉积物中MP的存在与池塘周围的人类活动有关。因此,大量的国会议员是污染的来源,有可能损害养殖奶鱼的营养质量。这项研究为地方政府制定更清洁的环境和改善人类健康的废物管理政策提供了重要信息。
    The widespread use of plastic has resulted in the accumulation of plastic waste across a range of sizes, notably including microplastics (MPs). The introduction of MPs into aquatic ecosystems can lead to the contamination of organisms, mainly fish. This study reports for the first time a quantitative and qualitative analysis conducted on the abundance of MPs encountered in water and sediment of milkfish aquaculture ponds in Gresik, East Java, Indonesia. Water and sediment samples were collected at three stations between February to April 2021. The abundance of MPs was analyzed through the application of one-way ANOVA tests and Pearson\'s correlation analysis. The results identified four types of MPs: fragments, fibers, films, and pellets. The highest abundance of MPs in both water (10.40 particle/L) and sediment samples (1.15 particle/g) was observed in March. The predominant MPs size in the water samples is 100-500 μm, while it is below 100 μm in the sediment. The color of the MPs varied across eight colors: black, purple, red, blue, yellow, pink, green, and transparent. The identification of MPs polymers was found to be polypropylene (PP), Polyurethane (PU), Polycarbonate (PC), Polyethylene terephthalate (PETE), High-density polyethylene (HDPE), and low-density polyethylene (LDPE). The presence of MPs in the water column and sediments was correlated with human activities around the ponds. Hence, the abundance of MPs is a source of pollution that has the potential to damage the nutritional quality of farmed milkfish. This study provides important information for the local governments to develop waste management policies for a cleaner environment and improved human health.
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  • 文章类型: Journal Article
    在药物化学中特别寻求蛋白质-片段复合物结构以合理设计前导分子。这些结构通常是使用X射线晶体学得出的,但故障率是不可忽视的。NMR是计算弱相互作用复合物的可能替代方法。然而,耗时的蛋白质信号分配步骤仍然是其常规应用的障碍。NMR分子置换(NMR2)是一种通用且快速的方法,可以阐明蛋白质-配体复合物的结构。它已成功应用于肽,类似药物的分子,最近还有碎片。由于碎片尺寸小,ca<300Da,解决蛋白质-片段复合物的结构尤其具有挑战性。这里,我们介绍了NMR2应用于蛋白质片段复合物时的预期性能。NMR2方法已与SERAPhic片段文库进行了基准测试,以确定蛋白质片段NMR结构计算中的技术挑战。提出了一种简单的策略来进一步提高方法的成功率。所提出的工作证实NMR2是X射线晶体学的替代方法,用于解决蛋白质片段复合物结构。
    Protein-fragment complex structures are particularly sought after in medicinal chemistry to rationally design lead molecules. These structures are usually derived using X-ray crystallography, but the failure rate is non-neglectable. NMR is a possible alternative for the calculation of weakly interacting complexes. Nevertheless, the time-consuming protein signal assignment step remains a barrier to its routine application. NMR Molecular Replacement (NMR2) is a versatile and rapid method that enables the elucidation of a protein-ligand complex structure. It has been successfully applied to peptides, drug-like molecules, and more recently to fragments. Due to the small size of the fragments, ca < 300 Da, solving the structures of the protein-fragment complexes is particularly challenging. Here, we present the expected performances of NMR2 when applied to protein-fragment complexes. The NMR2 approach has been benchmarked with the SERAPhic fragment library to identify the technical challenges in protein-fragment NMR structure calculation. A straightforward strategy is proposed to increase the method\'s success rate further. The presented work confirms that NMR2 is an alternative method to X-ray crystallography for solving protein-fragment complex structures.
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  • 文章类型: Journal Article
    确定获取脂肪抽吸物的最合适的套管直径很重要,就获得的材料的质量和成分而言,和易于实际使用的套管。套管的尺寸是影响所获得的脂肪抽吸物样品的定性特征以进一步用于脂肪组织的主要因素之一。研究的目的是在临床和组织形态上确定实验研究中从兔腹股沟脂肪垫收集脂肪抽吸物样品的最佳套管直径。动物模型的方法,外科手术,宏观检查,组织学检查,并应用形态计量学研究。在脂肪抽吸物中结缔组织纤维的百分比与插管的直径之间存在直接相关性。缺乏用于选择脂肪抽吸套管的明确标准是在随后使用脂肪组织的情况下获得普遍接受的脂肪抽吸方案的限制之一。在这项研究中,动物实验确定了最理想的套管直径,适合收集最大量的脂肪抽吸物用于后续使用。
    Determining the most appropriate cannula diameter for lipoaspirate harvesting is important, both in terms of the quality and composition of the material obtained, and the ease of practical use of the cannula. The size of the cannula is one of the main factors affecting the qualitative characteristics of the obtained lipoaspirate sample for further use of adipose tissue. The purpose of the investigation was to clinically and histomorphometrically determine the optimal cannula diameter for lipoaspirate samples collection from rabbit inguinal fat pad in an experimental study. The methods of Animal models, Surgical procedures, Macroscopic examination, Histological examination, and Morphometric study were applied. There is a direct correlation between the percentage of connective tissue fibres in the lipoaspirate and the diameter of the cannula. The lack of clear criteria for selecting a lipoaspiration cannula is one of the limitations to obtaining generally accepted lipoaspiration protocols with subsequent use of adipose tissue. In this study, the animal experiment determined the most ideal cannula diameter suitable for collecting the largest amount of lipoaspirate for subsequent use.
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  • 文章类型: Journal Article
    塑料和微塑料已在废弃渔船的处置地点以及切拉南鱼类登陆中心的高水位线(HWL)进行了量化和表征,印度。玻璃纤维增强塑料(FRP)对处置地点(〜4.5nm-2和18gm-2)的塑料池的贡献大于HWL(〜0.25nm-2和<1gm-2),并且是前者的微塑料池的丰富组成部分。微型FRP的红外分析揭示了各种树脂(例如,醇酸,聚酯,环氧树脂),而对细观尺寸的FRP的涂漆表面的X射线荧光分析返回了不同浓度的铜和铅。铅的浓度足够高,足以污染〜400mgkg-1的沙子。FRP的相对高密度及其与玻璃纤维和含金属涂料的关联导致颗粒与更“常规”(非复合)热塑性塑料的命运和毒性可能非常不同。
    Plastics and microplastics have been quantified and characterised at disposal sites of abandoned fishing boats and along the high-water line (HWL) of a fish landing centre in Chellanam, India. Fibreglass-reinforced plastic (FRP) made a greater contribution to the plastic pool at the disposal sites (~ 4.5 n m-2 and 18 g m-2) than the HWL (~ 0.25 n m-2 and < 1 g m-2) and was an abundant component of the microplastic pool at the former. Infrared analysis of micro-sized FRPs revealed various resins (e.g., alkyd, polyester, epoxy), while X-ray fluorescence analysis of the painted surfaces of meso-sized FRPs returned variable concentrations of copper and lead. Concentrations of Pb were high enough to contaminate sand up to ~400 mg kg-1. The relatively high density of FRP and its association with glass fibres and metal-bearing paints results in particles with potentially very different fates and toxicities to more \"conventional\" (non-composite) thermoplastics.
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  • 文章类型: Journal Article
    In 2010, Indonesia estimated as the second-largest country in the world that donates plastic to the sea. This study aims to investigate the spatial and temporal distribution of microplastics in tropical estuaries. The sampling was carried out in Benoa Bay with four repetitions representing the wet and dry seasons. Spatially it was found that the highest microplastic abundance around the Suwung landfill, while the lowest at Badung River Estuary, middle, and an inlet of the Benoa Bay. The highest percentage to the lowest microplastic based on the size was 500-1000 μm (37.9%), >1000 μm (35.7%), 300-500 μm (22.1%), and <300 μm (4.3%), while based on the shape were fragments (73.19%), foam (17.02%), fiber (6.38%), and granule (3.40%). No significant differences were found between the wet and dry seasons based on the abundance, but significantly varied based on size and shape. Polymers of microplastics were dominated by polystyrene, polypropylene, and polyethylene.
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    文章类型: Journal Article
    Reactive AA amyloidosis develops secondary to chronic inflammatory disorders. Serum amyloid A protein (SAA) and its degradation products, named AAs, are the main components of amyloid deposits, while apolipoprotein E (apoE) fragments are the minor components. To further understand the molecular mechanism of AA amyloidosis, we examined SAA/AAs moieties and apoE in the spleen and plasma throughout the amyloid-generating and amyloid-absorbing phases in a mouse model. SAA and four AA species (8.5kDa, 7.8kDa, 7.0kDa, and 6.2kDa) were detected in the spleen. SAA and the 8.5 kDa and 7.8 kDa AAs were prominent in the acute phase, whereas the 7.0kDa AA, the second smallest AA corresponding to the most common form in the human disease, was prominent in the chronic phase. These results indicate that the higher molecular weight species first constituted the fibril, followed by the 7.0kDa species, which were finally absorbed. ApoE was a component of the amyloid deposits at a degradation size from the beginning and was absorbed without being converted to another size. Degradation products, either from SAA or apoE, did not appear in the plasma during the course of the disease. A more detailed understanding of the moieties of amyloid-related peptides may help in the development of a method that can indicate the disease activity of AA amyloidosis.
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