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1.
Bilal Alashkar Alhamwe Daniel P. Potaczek Sarah Miethe Fahd Alhamdan Lukas Hintz Arslan Magomedov Holger Garn 《International journal of molecular sciences》2021,22(9)
Extracellular vesicles (EVs) are membranous structures, which are secreted by almost every cell type analyzed so far. In addition to their importance for cell-cell communication under physiological conditions, EVs are also released during pathogenesis and mechanistically contribute to this process. Here we summarize their functional relevance in asthma, one of the most common chronic non-communicable diseases. Asthma is a complex persistent inflammatory disorder of the airways characterized by reversible airflow obstruction and, from a long-term perspective, airway remodeling. Overall, mechanistic studies summarized here indicate the importance of different subtypes of EVs and their variable cargoes in the functioning of the pathways underlying asthma, and show some interesting potential for the development of future therapeutic interventions. Association studies in turn demonstrate a good diagnostic potential of EVs in asthma. 相似文献
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《Food Reviews International》2008,24(2):235-251
The traditional American rhyme says, “an apple a day keeps the doctor away.” What has made apples exceptional and appreciated for a million years? Besides their content of pectin, vitamins and minerals, they are considered to be a good source of antioxidants that scavenge and neutralize free radicals, which in turn play a role in the onset of cardiovascular diseases and cancers. Polyphenols are major antioxidants in apples, however, the antioxidants vary with the apple variety, and the post-harvest storage conditions. Further, the polyphenols are distributed differently throughout the fruit (skin or flesh). The paper reviews the present knowledge on apple polyphenols, their bioavailability and pro-health functionality. 相似文献
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ABSTRACT: A new natural apple polyphenol oxidase (PPO) inhibitor(s) from housefly ( Musca domestica L.) was discovered. Crude inhibitor (s) isolated by buffer extraction, heat treatment, and dialysis from housefly pupae inhibited the activity of apple PPO up to 90% at pH values above 5.0. Inhibition was strictly pH-dependent. The inhibitor(s) was further characterized by employing heat, freezing and thawing, irradiation, pH adjustment, and ultrafiltration studies. The potential PPO inhibitor(s) was stable to heating at 100 °C for 1 h, repeated freezing and thawing, and irradiation. The inhibitor(s) was most stable at pH around 5.0 and least stable at alkaline pH. The PPO inhibition profile of housefly during metamorphosis also was evaluated. 相似文献
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Enzymatic Browning in Apple Pulps 总被引:3,自引:0,他引:3
Enzymatic browning in Golden Delicious apple pulp was studied as related to degree of ripeness and temperature (3.5–31°C). Green apple pulp showed the highest rate of browning. This was attributable to differences in ascorbic acid (AA) content and polyphenoloxidase activity in young fruits. The rate of browning determined by CIE L* measurements followed complex temperature dependent kinetics, represented by a multiple linear effects with log time. Equal changes in L* parameter yielded straight lines in a log temperature vs log time plot. Inhibition with AA caused an initial slow rate of browning and a well defined break point associated with exhaustion of antioxidant properties of the AA. The greater the AA concentration the longer the initial period. 相似文献
7.
Isabelle Travers Alain Jacquet Adlaïde Brisset Claire Maite 《Journal of the science of food and agriculture》2002,82(9):983-989
Monitoring the hydrolysis or disappearance of starch by the starch iodine test is a simple procedure for determining the maturity of cider apples, but it does not indicate the exact amount of starch present. So far, studies of starch in apples have dealt exclusively with dessert apples. In this paper the relationship between the visual starch index, the dark‐coloured surface area and the real starch content was studied in two varieties of cider apple commonly used in Normandy (France). Starch determination in cider apples required adapting the protocol provided by the Boehringer enzymatic kit. The work led to proposing a simplified index with five scales instead of 10. This index gives the correspondences between the new and old scales as well as the probable starch contents for each new scale. © 2002 Society of Chemical Industry 相似文献
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Changes in soil pH, exchangeable aluminium (Al), calcium (Ca), magnesium (Mg), and potassium (K) and extractable manganese (Mn) were investigated after urea fertigation of a sandy loam soil in an apple orchard in New Zealand. Urea at three rates (0, 25, 50 kg N ha–1 yr–1 or 0, 16.9, 33.8 g N emitter–1 yr–1) was applied in 4 equal fertigations. Soil cores at 4 profile depths (0–10, 10–20, 20–40 and 40–60 cm) directly below and 20 cm from the emitter were sampled approximately 4 weeks after each fertigation and in the following winter. Results obtained showed that the largest changes in soil pH and cations occurred in soils directly below the emitter in the 50 kg N ha–1 yr–1 treatment where the soil pH decreased by 1.6 pH units at all soil depths. The lowest pH of 4.3 was observed at a depth of 27 cm. Exchangeable Al and extractable Mn levels increased to 11 meq kg–1 and 78µg g–1 respectively. Estimated losses of Ca, Mg and K from the upper soil profile depth (0–10 cm) represented 23, 63 and 27% of their respective total exchangeable levels. At lower profile depths (>20 cm), accumulation of displaced K was evident. Variable, and generally non-significant, chemical changes recorded in soils 20 cm from the emitter were attributed to restricted lateral water movement, and therefore urea movement, down the profile.The present study showed that one season of urea fertigation by trickle emitters, applied to a sandy loam, at half the rate conventionally applied to apple orchards (50 kg N ha–1 yr–1) resulted in pH and mineral element imbalances which were potentially and sufficiently severe to inhibit tree growth. 相似文献
10.
Robert F. Smith Harold D. Pierce Jr. John H. Borden 《Journal of chemical ecology》1991,17(7):1437-1447
The first known sex pheromone for the family Miridae is reported for the mullein bug,Campylomma verbasci (Meyer) (Heteroptera: Miridae). Extracts of and Porapak Q-trapped volatiles from females were attractive to males in field bioassays. Butyl butyrate and hexyl butyrate were the predominant compounds in the females' volatiles, but these compounds previously had been found to be inactive when released alone or in combination. Butyl butyrate in combination with an isolated trace chemical, (E)-crotyl butyrate (which was inactive alone), rivaled the attraction elicited by five live females. When synthetic butyl butyrate and (E)-crotyl butyrate in a 16: 1 ratio were released at 91 or 183 g/day, they comprised an effective attractant for male bugs. 相似文献