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91.
Hepatoprotective effect of Cassia obtusifolia seed extract and constituents against oxidative damage induced by tert‐butyl hydroperoxide in human hepatic HepG2 cells
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Md Yousof Ali Susoma Jannat Hyun Ah Jung Byung‐Sun Min Pradeep Paudel Jae Sue Choi 《Journal of Food Biochemistry》2018,42(1)
The aim of the present study was to investigate the hepatoprotective effects of different soluble fractions of methanolic derived Cassia obtusifolia seeds extract (COE) and its active components in tert‐butyl hydroperoxide (t‐BHP)‐induced oxidative stress in HepG2 cells. Among the tested fractions, the ethyl acetate (EtOAc) fraction was the most active hepatoprotective fraction. From the active EtOAc fraction, six anthraquinones (alaternin, emodin, aloe emodin, 2‐hydroxyemodin 1‐methyl ether, chryso‐obtusin‐2‐O‐β‐d ‐glucoside, and questin) and one naphthopyrone glycoside (cassiaside) were isolated. The cytotoxic effect in 200 µM t‐BHP‐induced HepG2 cells was inhibited by COE and their bioactive compounds. The protective effect of COE in 200 µM t‐BHP‐induced HepG2 cells may be associated with positive regulation of glutathione (GSH) and decreased in reactive oxygen species (ROS) formation of their bioactive compounds. The increased ROS and decreased GSH levels observed in t‐BHP‐treated HepG2 cells were ameliorated by pretreatment with cassiaside, alaternin, and aloe emodin, indicating that the hepatoprotective effects of these major constituents are mediated by induction of cellular defense against oxidative stress. Overall, COE displayed a significant cytoprotective effect against oxidative stress, which may most likely be because of active compounds like cassiaside, alaternin, and aloe emodin in COE, which leads to maintenance of the normal redox status of cells.
Practical applications
The dried and roasted seeds of Cassia obtusifolia are commonly consumed as brew tea and medicinal foods in Korea. The seeds have multiple therapeutic actions related to the treatment of liver disease, dementia, diabetes, eye inflammation, photophobia and lacrimation, dysentery, headache, as well as dizziness. The present study demonstrates the hepatoprotective effect through prevention of oxidative stress, suggesting that C. obtusifolia and its constituents may have beneficial effects in preventing hepatic diseases. 相似文献92.
93.
Sue Gollifer 《Digital Creativity》2013,24(3):159-168
Cyberart incorporates interactive systems within artistic practices. The foundation for a theory of artistic production and creativity becomes expanded on the basis of a biological implication that is not dependent solely on aesthetic judgment. To communicate with computers and their high performance software stimulates artists’ imagination and there are types of interface or hardware that connect the natural system (especially the body) to the internal life of computers. 相似文献
94.
Schoener CA Hutson HN Fletcher GK Peppas NA 《Industrial & engineering chemistry research》2011,50(22):12556-12561
To investigate the delivery of hydrophobic therapeutic agents, a novel class of interpenetrating networks (IPNs) were synthesized and composed of two networks: methacrylic acid grafted with poly(ethylene glycol) tethers, P(MAA-g-EG), and poly(n-butyl acrylate) (PBA). The hydrophilic P(MAA-g-EG) networks are pH-responsive hydrogels capable of triggered release of an encapsulated therapeutic agent, such as a low molecular weight drug or a protein, when it passes from the stomach (low pH) to upper small intestine (neutral pH). PBA is a hydrophobic homopolymer that can affect the IPN swelling behavior, the therapeutic agent loading efficiencies in IPNs, and solute release profiles from IPNs. In dynamic swelling conditions, IPNs had greater swelling ratios than P(MAA-g-EG), but in equilibrium swelling conditions the IPN swelling ratio decreased with increasing PBA content. Loading efficiencies of the model therapeutic agent fluorescein ranged from 21 - 44%. Release studies from neat P(MAA-g-EG) and the ensuing IPNs indicated that the transition from low pH (2.0) to neutral pH (7.0) triggered fluorescein release. Maximum fluorescein release depended on the structure and hydrophilicity of the carriers used in these studies. 相似文献
95.
The growth, capacitance and frequency response of vertically-oriented graphenes grown by radio frequency plasma-enhanced chemical vapor deposition on nickel substrates and used as electrodes in electric double layer capacitors (EDLCs) are presented. The graphenes grown on the grain boundary of substrates show a faster growth rate, but less ordered structure than in the center of the nickel grain. At a few nanometers away from the grain boundaries the graphenes grow vertically at the rate of 70–80 nm per minute. The film height increased linearly with growth time from 700 nm (10 min sample) to 3.1 μm (40 min sample). Raman spectra show that the intensity ratio of the D band to G band gradually decreased with growth time to a value of 0.5, indicating that the crystalline order of the graphene increases with height. The specific capacitance of symmetric, parallel plate EDLC devices fabricated with these films was found to increase in a linear fashion with growth time up to values greater than 120 μF/cm2 at 1 kHz. An impedance phase angle of ?45° was reached at 30 kHz. Specific capacitance normalized to growth height suggests that mechanisms other than double layer charge storage on planar surface area were operative. 相似文献
96.
Simultaneous determination of acetoin and tetramethylpyrazine in traditional vinegars by HPLC method
A rapid and selective HPLC method was developed for the simultaneous analysis of acetoin (ACT) and tetramethylpyrazine (TMP). The chromatography was performed on a Zorbax SB-C18 column at 45 °C, with an aqueous mobile phase (1% acetic acid and 0.05% trifluoroacetic acid in water, pH 2.5)–(methanol) (45:55, v/v). The flow rate was 0.8 mL/min and UV detection wavelength was 297 nm. This method permits the simultaneous determination of ACT and TMP in fermentative foods with detection limits of 5.625 and 0.033 μg/mL, respectively. The recovery was 96.03% for ACT and 92.06% for TMP. Correlation coefficients were greater than 0.9999 for the two compounds. The linearity ranges for ACT and TMP were in the range of 0.02–20 mg/L and 0.12–80 μg/mL, respectively. The proposed method could be used for routine quality control of foods, beverages, natural products, or pharmaceuticals. Current data suggest that the content of TMP in vinegars is positively correlated with that of ACT. 相似文献
97.
Team-oriented software practicum 总被引:1,自引:0,他引:1
New computer science graduates are inadequately prepared to apply their abstract knowledge, and they have rarely worked in the teams required in modern business. To remedy these shortcomings and alleviate the low motivation that often accompanies the first years of college, we proposed that a pilot group of entering freshmen should be formed into a four-year experimental team. Unlike traditional course-at-a-time approaches, this supplements the existing curriculum by integrating material across courses through team construction of software projects. Under the guidance of faculty and graduate student mentors, students work cooperatively on projects related not just to programming but to the entire lifecycle of software production, from market analysis to revision based on technical support. Initial projects are team-oriented and scaled to the capabilities of entering students while final projects span the product development cycle and involve several semesters of effort. Industrial representatives provide a practical perspective by presenting seminars on special topics and evaluating student projects in light of professional standards. This type of experiment provides the industrial community with students better prepared to face the challenges of professional software development. It also offers consolidated learning, enhanced student retention, significant student-faculty involvement, and the potential to identify learning experiences that may be usefully integrated into existing courses 相似文献
98.
Accumulating evidence strongly suggests that oxidative stress underlies aging processes. Research provides consistent evidence that calorie restriction (CR) reduces age-related oxidative stress and has anti-inflammatory properties. However, information is lacking on the molecular mechanism that would better define the interrelation of reactive oxygen species and nitrogen species and the pro-inflammatory states of the aging process. In this review, the biochemical and molecular bases of the inflammatory process in the aging process are analyzed to delineate the molecular inflammation hypothesis of aging. The key players involved in the proposed hypothesis are the age-related upregulation of NF-kappa B, IL-1 beta, IL-6, TNFalpha, cyclooxygenase-2, and inducible NO synthase, all of which are attenuated by CR. Furthermore, age-related NF kappa B activation is associated with phosphorylation by I kappa B kinase/NIK and MAPKs, while CR blocked these activation processes. The modulation of these factors provides molecular insights of the anti-inflammatory action of CR in relation to the aging process. Based on available finding and our recent supporting evidence, we prefer to use "molecular inflammation" to emphasize the importance of the molecular reaction mechanisms and their aberrance, predisposing to fully expressed chronic inflammatory phenomena. It was further proposed that CR's major force of the regulation of redox-sensitive inflammation may well be its life-prolonging action. 相似文献
99.
100.
Abstract: Picture sorts were used to investigate perceptions of women's office clothes, with a sample of ten male and ten female subjects who normally worked in an office environment. The pictures on the cards were taken from catalogues, and showed women's outfits which might be worn in an office. The subjects sorted the cards repeatedly and generated criteria and categories of their own choice. Some of the criteria and categories had not been previously reported in the clothing research literature. Over half of the male subjects, but none of the female subjects, used ‘married/unmarried woman’ as a sorting criterion, although only one of the images sorted showed a wedding ring. A significantly higher proportion of male than of female subjects used dichotomous categorization (i.e. sorting the cards into two piles for one or more of the criteria). The reasons for this are obscure, but do not appear to be a simple outcome of males not knowing much about female clothing. Previous research into clothing has tended to involve researcher‐centred approaches such as semiotics; the results from this study suggest that there would be advantages in wider use of subject‐centred approaches such as card sorts, both in this domain and elsewhere. It was concluded that card sorts were a useful method and should be more widely used. 相似文献