Antioxidant properties of banana flower of two cultivars in China using 2,2-diphenyl-1-picrylhydrazyl (DPPH,) reducing power, 2,2’-azinobis-(3-ethylbenzthiazoline-6- sulphonate (ABTS) and inhibition of lipid peroxidation assays

In this study, the antioxidant properties of banana flower extracts (cvs. Baxijiao (AAA) and Paradisiaca (AAB)) were analysed by using several biochemical assays which include 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, reducing power, 2, 2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate (ABTS) radical scavenging activities and inhibition of lipid peroxidation in egg lecithin through the formation of thiobarbituric acid-reactive substances (TBARS). These assays have been extensively studied and generally accepted as models to characterize peroxidative damage in biomembranes. In the present study, the EC50 values were calculated using each method as listed above was used to compare the antioxidant efficiency of each banana flower extract. The phenol, flavonoid, vitamin E and saponin contents were also analyzed. Baxijiao flower extract revealed better antioxidant properties by presenting much lower EC50 values, particularly for reducing power. In addition, antioxidant concentrations (polyphenols and flavonoids) were found higher in this flower sample than those in the Paradisiaca sample. The results suggested that the Baxijiao flower could be a better resource either as a dietary supplement or as a food additive than the later one.Key words: Banana flower, antioxidant, scavenging effects, peroxidation

Decadal link between longitudinal morphological changes in branching channels of Yangtze Estuary and movement of the offshore depo-center

In estuaries, the morphology of inland and offshore areas usually evolves synergistically. This study examines the decadal link between longitudinal changes in morphology of branching channels and movement of the offshore depo-center (where sediment deposition rate is maximum) of the Yangtze River estuary, under intense human interference. Integrated data analysis is provided on morphology, runoff discharge, and ebb partition ratio from 1950 to 2017. Channel-volume reductions and change rates between isobaths in branching channels reflect the impact of estuarine engineering projects. Ebb partition ratio and duration of discharge ≥ 60 000 m3 s-1 act as proxies for the water excavating force in branching channels and runoff intensity. It is found that deposition occurs in the lower/upper sub-reaches (or further downstream/upstream channels) of the inland north/south branching channels, and the offshore depo-center moves southward or southeastward, as runoff intensity grows; the reverse occurs as runoff intensity declines. This is because the horizontal circumfluence in the Yangtze estuary rotates clockwise as ebb partition ratios of the north/south branching channels increase/decrease for increasing runoff, and conversely rotates anticlockwise for decreasing runoff. Land reclamation activities, the Deepwater Channel Project, and the Qingcaosha Reservoir have impacted greatly on longitudinal changes of morphology in the North Branch and the South Passage and on ebb partition ratio variations in the North/South Channel and the North/South Passage. Dam-induced runoff flattening has enhanced deposition in the upper/lower sub-reaches of the north/south branching channels and caused northward movement of the offshore depo-center, except in areas affected by estuarine engineering projects. Dam-induced longitudinal evolution of branching channel morphology and offshore depo-center movement will likely persist in the future, given the ongoing construction of large cascade dams in the upper Yangtze and the completion of major projects in the Yangtze estuary

Altered mRNA expression of genes related to nerve cell activity in the fracture callus of older rats: A randomized, controlled, microarray study

BACKGROUND: The time required for radiographic union following femoral fracture increases with age in both humans and rats for unknown reasons. Since abnormalities in fracture innervation will slow skeletal healing, we explored whether abnormal mRNA expression of genes related to nerve cell activity in the older rats was associated with the slowing of skeletal repair. METHODS: Simple, transverse, mid-shaft, femoral fractures with intramedullary rod fixation were induced in anaesthetized female Sprague-Dawley rats at 6, 26, and 52 weeks of age. At 0, 0.4, 1, 2, 4, and 6 weeks after fracture, a bony segment, one-third the length of the femur, centered on the fracture site, including the external callus, cortical bone, and marrow elements, was harvested. cRNA was prepared and hybridized to 54 Affymetrix U34A microarrays (3/age/time point). RESULTS: The mRNA levels of 62 genes related to neural function were affected by fracture. Of the total, 38 genes were altered by fracture to a similar extent at the three ages. In contrast, eight neural genes showed prolonged down-regulation in the older rats compared to the more rapid return to pre-fracture levels in younger rats. Seven genes were up-regulated by fracture more in the younger rats than in the older rats, while nine genes were up-regulated more in the older rats than in the younger. CONCLUSIONS: mRNA of 24 nerve-related genes responded differently to fracture in older rats compared to young rats. This differential expression may reflect altered cell function at the fracture site that may be causally related to the slowing of fracture healing with age or may be an effect of the delayed healing

The disruption of proteostasis in neurodegenerative diseases

Cells count on surveillance systems to monitor and protect the cellular proteome which, besides being highly heterogeneous, is constantly being challenged by intrinsic and environmental factors. In this context, the proteostasis network (PN) is essential to achieve a stable and functional proteome. Disruption of the PN is associated with aging and can lead to and/or potentiate the occurrence of many neurodegenerative diseases (ND). This not only emphasizes the importance of the PN in health span and aging but also how its modulation can be a potential target for intervention and treatment of human diseases.info:eu-repo/semantics/publishedVersio

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field

Determination of the α -decay half-life of Po 210 based on film and slice bismuth samples at room temperature

The α decay rate of Po210 was measured in a film sample (Po210@Bi2O3) and a slice sample (Po210@Bimetal), respectively. The former was used as a reference sample. The half-lives of Po210@Bi2O3 and Po210@Bi metal environments were observed to be (138.40±0.21d) and (138.87±0.87d) at room temperature, respectively. It was found that the half-life of Po210 is consistent with international recommendations within the uncertainty limits, and we did not find any deviation of the α decay rate of Po210 between film sample (Po210@Bi2O3) and slice sample (Po210@Bimetal)