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71.
Yutang Wu Zhizhao Chen Yaoguo Wang Fangzhan Peng 《Journal of cellular biochemistry》2020,121(3):2363-2371
Endothelium, the inner cellular lining of blood vessels, has an important role in the regulation of physiological processes and its dysfunction may initiate cardiovascular complications. Previous investigations have revealed that dietary docosahexaenoic acid (DHA) is related to a lower possibility of cardiovascular disease and mortality. Until now, the molecular mechanisms in the biological activities of DHA remain largely unknown. MicroRNAs (miRNAs) play a vital role in regulating gene expression. Thus, we aimed to investigate whether DHA improves the dysfunction via regulating miRNAs. To understand the protective effects of DHA through modulating miR-3691-5p and its target genes for palmitic acid (PAL) induced apoptosis in endothelial cells. The present study demonstrated that DHA upregulated miR-3691-5p expression, and downregulated the expression of its target gene serpin family E member 1 (SERPINE1). MiR-mimics and inhibitors modulation results indicated that miR-3691-5p regulates endothelial apoptosis through activating antiapoptotic response which controlled by the STAT3 signaling pathway. In conclusion, we have shown that PAL-induced apoptosis could be decreased by DHA treatment through miR-3691-5/SERPINE1 pathways. 相似文献
72.
Timm Intemann Kirsten Mehlig Stefaan De Henauw Alfonso Siani Tassos Constantinou Luis A. Moreno Dénes Molnár Toomas Veidebaum Iris Pigeot 《Biometrical journal. Biometrische Zeitschrift》2020,62(1):221-237
Modelling dietary data, and especially 24-hr dietary recall (24HDR) data, is a challenge. Ignoring the inherent measurement error (ME) leads to biased effect estimates when the association between an exposure and an outcome is investigated. We propose an adapted simulation extrapolation (SIMEX) algorithm for modelling dietary exposures. For this purpose, we exploit the ME model of the NCI method where we assume the assumption of normally distributed errors of the reported intake on the Box-Cox transformed scale and of unbiased recalls on the original scale. According to the SIMEX algorithm, remeasurements of the observed data with additional ME are generated in order to estimate the association between the level of ME and the resulting effect estimate. Subsequently, this association is extrapolated to the case of zero ME to obtain the corrected estimate. We show that the proposed method fulfils the key property of the SIMEX approach, that is, that the MSE of the generated data will converge to zero if the ME variance converges to zero. Furthermore, the method is applied to real 24HDR data of the I.Family study to correct the effects of salt and alcohol intake on blood pressure. In a simulation study, the method is compared with the NCI method resulting in effect estimates with either smaller MSE or smaller bias in certain situations. In addition, we found our method to be more informative and easier to implement. Therefore, we conclude that the proposed method is useful to promote the dissemination of ME correction methods in nutritional epidemiology. 相似文献
73.
Petr Martinek Josef Hedbávný Tomáš Kudláček Michal Šťasta Emanuel Kula 《Entomologia Experimentalis et Applicata》2020,168(8):635-643
The adaptation of insects to environmental changes can constitute a crucial factor in their development and activity. The response of Cabera pusaria L. (Lepidoptera: Geometridae) caterpillars to high manganese (Mn) concentrations in the diet was studied. Birch leaves were treated by dipping in MnCl2·4H2O solutions, thereby achieving Mn contents of 370 (T0), 695 (T1), 3 198 (T2), and 6 302 mg kg−1 (T3). The reactions were determined by observing caterpillar mortality, development time, food consumption, and pupal weight. Manganese concentrations in larval excrement, pupae, and food were determined. Manganese in the diet at unnaturally increased concentrations caused great stress for caterpillars. All individuals in the treatment with the highest Mn concentration (T3) died during rearing and successful pupation occurred in only four individuals in T2. Even in the case of caterpillars from T1 (twofold higher than T0) a negative reaction (increased food consumption and prolonged development) was recorded. We also determined significantly increased Mn concentration in pupae from T1 (T2 and T3 were not included in this evaluation due to mortality) and excrement (T1‒T3) compared with T0 having a natural Mn concentration. Caterpillars were seen to eliminate negatively acting dietary Mn by its translocation to excrement. However, the highest mortality rate in T2 and T3 and negative reactions of individuals in T1 very likely demonstrate energy insufficiency and the high energy requirements of Mn elimination mechanisms. 相似文献
74.
肠道菌群多糖利用及代谢 总被引:1,自引:1,他引:0
宿主与肠道共生菌之间存在一种互利共生的关系。肠道共生菌可以代谢宿主自身不能消化的多糖。进入肠道内的多糖是影响肠道共生菌生理状态和组成的重要因素,这些多糖主要来自饮食和宿主的粘膜分泌物。人类饮食中含有几十种不同的膳食多糖,其中大多数不能被人类基因组中编码的酶降解,并进入大肠,供肠道共生菌利用。肠道共生菌将这些不易消化的多糖转化为短链脂肪酸,作为大肠细胞和其他肠道上皮细胞的营养物质。除此之外,短链脂肪酸对人体健康有着重要的影响。不同的肠道共生菌对进入肠道内的多糖具有不同的偏好性,表明摄入膳食多糖是一种可以直接影响肠道内共生菌物种平衡的策略。因此,研究肠道菌群的多糖代谢机制具有重要的意义。本文从肠道共生菌的组成、利用进入肠道内多糖的机制,以及产生的代谢产物可能对人体健康存在的潜在影响等方面进行了综述,并介绍了代表性的肠道共生菌如拟杆菌和双歧杆菌利用多糖的途径及特征。 相似文献
75.
《Anthrozo?s》2013,26(4):332-342
AbstractStudies have explored the motivations behind the decision to become vegetarian, and have explored the well being of vegetarians. However, little research has focused on the social psychological and interpersonal aspects of vegetarianism. The focus of this study was to develop a scale designed to measure attitudes toward vegetarians (ATVS). This scale measures a one-factor construct with adequate internal consistency. The ATVS correlated significantly with the construct of authoritarianism, and, as expected, the ATVS did not correlate significantly with social desirability. In addition, attitudes toward vegetarians were found to be generally positive. The positive attitudes toward vegetarians may be the result of using a college student population that was overwhelmingly female. 相似文献
76.
Shashi Bhushan Kalpana Kalia Madhu Sharma Bikram Singh P. S. Ahuja 《Critical reviews in biotechnology》2013,33(4):285-296
The growth of horticulture industries worldwide has generated huge quantities of fruit wastes (25%–40% of the total fruits processed). These residues are generally a good source of carbohydrates, especially cell wall polysaccharides and other functionally important bioactive molecules such as proteins, vitamins, minerals and natural antioxidants. “Apple pomace” is a left-over solid biomass with a high moisture content, obtained as a by-product during the processing of apple fruits for juice, cider or wine preparation. Owing to the high carbohydrate content, apple pomace is used as a substrate in a number of microbial processes for the production of organic acids, enzymes, single cell protein, ethanol, low alcoholic drinks and pigments. Recent research trends reveal that there is an increase in the utilization of apple pomace as a food processing residue for the extraction of value added products such as dietary fibre, protein, natural antioxidants, biopolymers, pigments and compounds with unique properties. However, the central dogma is still the stability, safety and economic feasibility of the process(s)/product(s) developed. This review is mainly focused on assessing recent research developments in extraction, isolation and characterization of bioactive molecules from apple pomace, along with their commercial utilization, in food fortification. 相似文献
77.
This study was designed to identify psychophysical channels responsible for the detection of hand-transmitted vibration. Perception thresholds for vibration (16, 31.5, 63 and 125?Hz sinusoidal for 600?ms) at the distal phalanx of the middle finger and the whole hand were determined with and without simultaneous masking stimuli (1/3 octave bandwidth Gaussian random vibration centered on either 16?Hz or 125?Hz for 3000?ms, varying in magnitude 0 to 30?dB above threshold). At all frequencies from 16 to 125?Hz, absolute thresholds for the hand were significantly lower than those for the finger. Changes in threshold as a function of masker level were used to estimate the thresholds of three psychophysical channels (i.e. P, NP I, and NP II channels). Increased vibrotactile sensitivity of the hand compared to the finger seems to be not entirely due to increased spatial summation via the Pacinian system (P channel); non-Pacinian system (NP I and NP II channels) also contributed to perception. Differing transmission of vibration between the hand and the finger may have also influenced the thresholds. 相似文献
78.
Jovana Milanovic Sonja Schiehser Predrag Milanovic Antje Potthast Mirjana Kostic 《Carbohydrate polymers》2013
The effects of TEMPO-mediated oxidation, performed with NaClO, a catalytic amount of NaBr, and 2,2′,6,6′-tetramethylpiperidine-1-oxy radical (TEMPO), were studied on lyocell fibers by means of GPC using multiple detection and group-selective fluorescence labeling according to the CCOA and FDAM methodology. The applied method determines functional group content as a sum parameter, as well as functional group profiles in relation to the molecular weight of the cellulose fibers. Both the CHO and COOH profiles, as well as molecular weight alterations, were analyzed. A significant decrease in the average molecular weight was obtained during the first hour of TEMPO-mediated oxidation, but prolonged oxidation time resulted in no strong additional chain scission. Significant amounts of COOH groups were introduced in the high molecular weight fractions by the oxidation with higher concentrations of NaClO (2.42–9.67 mmol NaClO/g fiber) after modification times of 1 h or longer. 相似文献
79.
Tadashi Sudo Hideo Nagayama Kinjiro Tamari 《Bioscience, biotechnology, and biochemistry》2013,77(11):2535-2542
In order to explain the difference in extracellular cellulase activities (C1 and Cx enzyme activities) among various strains of P. oryzae, the elution patterns from the column were compared among various strains, following each step of the partial purification.The crude enzymes, prepared by ammonium sulfate fractionation (0.2~0.8 sat.) from the culture filtrates, which were obtained from various strains of P. oryzae cultured on rice plant powder as the carbon source, were fractionated by DEAE-Sephadex A–50 chromatography into two components; the passing-through fraction (I) and the fraction (II) adsorbed and eluted from the column with 0.5 M NaCl The percentage of the enzyme activity (Cx enzyme activity) in fraction I to that of the crude extract was found to vary chracteristically according to the strain, and the variation was in a good correlation to that of the extracellular cellulase activities.Fractions I and II were then separated by Sephadex G–100 into two (peaks a and b) and at least five (peaks c, d, e, f and g) components, respectively. The activities in peaks a, b and g were found to vary according to the strain, while those of peaks c and e were common among various strains.The cell wall fraction prepared from C–3 strain, which was previously shown to be low in enzyme activity and thus out of the correlation between the degree of pathogenicity and extracellular cellulase activity, was found to exhibit higher cellulase activities (C1 and Cx enzyme activities) than those of other strains examined. Thus, the low extracellular cellulase activity in the case of C–3 strain was suggested to be due to the abnormality in the mechanism of enzyme excretion. 相似文献
80.
Yoshiaki Nakahara Masanao Matsui Kenji Mori 《Bioscience, biotechnology, and biochemistry》2013,77(11):2243-2245
A novel synthetic method of 3-substituted furans was developed and syntheses of perillen and dendrolasin are described. 相似文献